Academic literature on the topic 'Temperature log'
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Journal articles on the topic "Temperature log"
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Kohout, Jan, and Stanislav Vĕchet. "Low-Temperature and High-Temperature Anomalies in Temperature Shift of Stress-Lifetime Fatigue Curves." Materials Science Forum 567-568 (December 2007): 113–16. http://dx.doi.org/10.4028/www.scientific.net/msf.567-568.113.
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Most families of S-N curves determined at various temperatures present certain general regularities on whose basis the Basquin equation describing finite-life S-N curves can be generalized for various temperatures. This equation can be represented by straight lines with common slope if log-log fit for stress vs. temperature dependence is used. Deviations from these straight lines (anomalies) are evidence that additional degradation mechanisms are effective besides fatigue, whose temperature dependences differ from the mentioned temperature dependence of fatigue strength. In high-temperature region it is most often cyclic creep, in low-temperature region athermal processes of plastic deformation can play significant role in fatigue failure.
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Longmore, A. J., R. Dixon, I. Skillen, R. F. Jameson, and J. A. Fernley. "RR Lyrae Stars and the Sandage Period-Shift Effect Examined Using IR-Derived Temperatures." International Astronomical Union Colloquium 111 (1989): 274. http://dx.doi.org/10.1017/s0252921100011829.
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AbstractMean temperatures for RR Lyrae stars in 7 globular clusters (M3, M4, M5, M15, M107, ω Cen and NGC 5466) have been determined using the optical-infrared colour <V>-<K> as a temperature indicator. Where <K> has been relatively well determined, from means of 3 or more observations, the scatter in relationships such as Log P’ vs log (temperature) and log (temperature) vs (blue amplitude) is significantly reduced when IR-derived temperatures are used instead of those derived from (B-V). Within the observational errors, the gradient in the log P’ vs log (temperature) diagram is the same for each cluster. Temperatures derived from <V>-<K> should also be less sensitive to metallicity differences than their optically derived counterparts. The Sandage Period-Shift Effect has therefore been re-examined using 6 of the 7 clusters (NGC 5466 was excluded because of too few data). A strong correlation between period-shift and metallicity is found; a smaller shift (but in the same sense) is also found for the temperature – amplitude relationship.
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INGHAM, STEVEN C., BARBARA H. INGHAM, DARAND BORNEMAN, EMILIE JAUSSAUD, ERICA L. SCHOELLER, NATHAN HOFTIEZER, LAUREN SCHWARTZBURG, GREG M. BURNHAM, and JOHN P. NORBACK. "Predicting Pathogen Growth during Short-Term Temperature Abuse of Raw Sausage." Journal of Food Protection 72, no. 1 (January 1, 2009): 75–84. http://dx.doi.org/10.4315/0362-028x-72.1.75.
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Lag-phase duration (LPD) and growth rate (GR) values were calculated from experimental data obtained using a previously described protocol (S. C. Ingham, M. A. Fanslau, G. M. Burnham, B. H. Ingham, J. P. Norback, and D. W. Schaffner, J. Food Prot. 70:1445–1456, 2007). These values were used to develop an interval accumulation-based tool designated THERM (temperature history evaluation for raw meats) for predicting growth or no growth of Salmonella serovars, Escherichia coli O157:H7, and Staphylococcus aureus in temperature-abused raw sausage. Data (time-temperature and pathogen log CFU per gram) were obtained from six inoculation experiments with Salmonella, E. coli O157:H7, and S. aureus in three raw pork sausage products stored under different temperature abuse conditions. The time-temperature history from each experiment was entered into THERM to predict pathogen growth. Predicted and experimental results were described as growth (>0.3 log increase in CFU) or no growth (≤0.3 log increase in CFU) and compared. The THERM tool accurately predicted growth or no growth for all 18 pathogen-experiment combinations. When compared with the observed changes in log CFU values for the nine pathogen-experiment combinations in which pathogens grew, the predicted changes in log CFU values were within 0.3 log CFU for three combinations, exceeded observed values by 0.4 to 1.5 log CFU in four combinations, and were 1.2 to 1.4 log CFU lower in two combinations. The THERM tool approach appears to be useful for predicting pathogen growth versus no growth in raw sausage during temperature abuse, although further development and testing are warranted.
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Douaa, Alsaeed, and Deri Fawaz. "Rheological and Prediction of melt viscosity flow curves for blend of Polycarbonate (PC) and Polyacrylonitrile butadiene styrene (ABS)." International Journal of ChemTech Research 12, no. 6 (2019): 33–40. http://dx.doi.org/10.20902/jctr.2019.120605.
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A knowledge of the variation of melt viscosity of thermoplastic polymers with both shear rate and temperature is of considerable importance to plastics engineers as well as to polymer rheologists. The Actual measurement of melt viscosity at large number of temperatures and shear rates is frequently a tedious and time-consuming task. The experimental validity for superimposing Log shear stress – Log shear rate curves at different temperatures along the log shear rate axis has been established for the mixture of (polycarbonate and polyacrylonitrile butadiene styrene). The temperature dependence of the resultant shift factors has been determined to predict viscosities as a function of temperature and shear rate is discussed
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PAN, HAO, MATTHEW BUENCONSEJO, KARL F. REINEKE, and Y. CAROL SHIEH. "Effect of Process Temperature on Virus Inactivation during High Hydrostatic Pressure Processing of Contaminated Fruit Puree and Juice." Journal of Food Protection 79, no. 9 (September 1, 2016): 1517–26. http://dx.doi.org/10.4315/0362-028x.jfp-16-004.
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ABSTRACT High pressure processing (HPP) can inactivate pathogens and retain fruit qualities. Elevated HPP pressure or time increases virus inactivation, but the effect of temperature is not consistently observed for norovirus and hepatitis A virus. In the present study, the effectiveness of HPP holding temperatures (<40°C) and pressures were evaluated for inactivating surrogates (murine norovirus [MNV] and MS2 coliphage) in pomegranate and strawberry juices and strawberry puree using a 24-liter HPP system. The holding temperature was established by setting the HPP initial temperature via pretrials. All trials were able to arrive at the designated holding pressure and holding temperature simultaneously. MNV inactivation in juices was conducted at 300 MPa for 3 min with various holding temperatures (10 to 30°C). A regression equation was derived, Y = −0.08 × X + 2.6 log PFU, R2 = 0.96, where Y is the log reduction and X is the holding temperature. The equation was used to predict a 2.6-log reduction in juices at 0°C holding temperature and indicated that MNV inactivation was inversely proportional to temperature increase. MNV survival during HPP did not differ significantly in pomegranate and strawberry juices. However, MS2 coliphage inactivation was greater as the holding temperature increased (from 15 to 38°C) at 600 MPa for 3 min. The increased inactivation trend is presumably similar to that for hepatitis A virus, but the holding temperature was not correlated with the reduction of HPP-resistant MS2 in strawberry puree. When the HPP holding pressure was evaluated independently in strawberry puree, a 5-log reduction of MNV was predicted through regression analysis at the holding pressure of 424 MPa for 3 min at 20°C. These parameters should inactivate >5 log PFU of MNV in juices, based upon a greater inactivation in berry juice than in puree (1.16-versus 0.74-log reduction at 300 MPa). This research illustrates use of predictive inactivation and a feasible means for manipulating HPP parameters for effective virus inactivation in fruit juices and puree.
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Tirta, Gabriella Devina, Leon Martin, Mario Donald Bani, Katherine Kho, Ihsan Tria Pramanda, Liew Phing Pui, Yu Hsuan How, Crystale Siew Ying Lim, and Putu Virgina Partha Devanthi. "Spray Drying Encapsulation of Pediococcus acidilactici at Different Inlet Air Temperatures and Wall Material Ratios." Foods 12, no. 1 (December 28, 2022): 165. http://dx.doi.org/10.3390/foods12010165.
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Pediococcus acidilactici has gained research and commercial interest due to its outstanding probiotic properties, yet its survival during storage and consumption requires improvement. This study aims to enhance P. acidilactici survival using spray drying encapsulation. Different inlet air temperatures (120 °C, 150 °C, and 170 °C) and whey protein isolate (WPI):gum arabic (GA) ratios (1:1, 3:1, 1:3) were tested. Cell viability was significantly (p < 0.05) affected by the inlet temperature but not the WPI:GA ratio. Increasing the inlet temperature to 170 °C significantly decreased P. acidilactici viability by 1.36 log cycles, from 8.61 log CFU/g to 7.25 log CFU/g. The inlet temperature of 150 °C resulted in a powder yield (63.12%) higher than at 120 °C (58.97%), as well as significantly (p < 0.05) lower moisture content (5.71%) and water activity (aw 0.21). Viable cell counts in all encapsulated P. acidilactici were maintained at 5.24–6.75 log CFU/g after gastrointestinal tract (GIT) simulation, with WPI:GA of 3:1 and inlet temperature 150 °C having the smallest log reduction (0.3 log cycles). All samples containing different WPI:GA ratios maintained sufficient viability (>7 log CFU/g) during the first three weeks of storage at 25 °C. These results could provide insights for further developing P. acidilactici as commercial probiotic products.
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Brzic, Sasa, Ljiljana Jelisavac, Jela Galovic, Danica Simic, and Jelena Petkovic. "Viscoelastic properties of hydroxyl-terminated poly(butadiene) based composite rocket propellants." Chemical Industry 68, no. 4 (2014): 435–43. http://dx.doi.org/10.2298/hemind130426067b.
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In the present study, the viscoelastic response of three composite solid propellants based on hydroxyl-terminated poly(butadiene), ammonium perchlorate and aluminum has been investigated. The investigation was surveyed by dynamic mechanical analysis over a wide range of temperatures and frequencies. The mechanical properties of these materials are related to the macromolecular structure of the binder as well as to the content and nature of solid fillers. The storage modulus, loss modulus, loss factor and glass transition temperature for each propellant sample have been evaluated. The master curves of storage (log G' vs log ?) and loss modulus (log G'' vs log ?) were generated for each propellant. A comparison of logaT vs temperature curves for all propellants indicate conformance to Williams-Landel-Ferry equation. Choosing the glass transition as the reference temperature, WLF equation constants are determined. Fractional free volume at the glass transition temperature and thermal coefficient of free volume expansion values are in accordance with the consideration that Al is reinforcing filler.
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MURPHY, R. Y., K. H. DRISCOLL, L. K. DUNCAN, T. OSAILI, and J. A. MARCY. "Thermal Lethality of Salmonella in Chicken Leg Quarters Processed via an Air/Steam Impingement Oven." Journal of Food Protection 67, no. 3 (March 1, 2004): 493–98. http://dx.doi.org/10.4315/0362-028x-67.3.493.
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Chicken leg quarters were injected with 0.1 ml of the cocktail culture per cm2 of the product surface area to contain about 7 log(CFU/g) of Salmonella. The inoculated leg quarters were processed in an air/steam impingement oven at an air temperature of 232°C, an air velocity of 1.4 m/s, and a relative humidity of 43%. The endpoint product temperatures were correlated with the cooking times. A model was developed for pathogen thermal lethality up to 7 log(CFU/g) reductions of Salmonella in correlation to the product mass (140 to 540 g) and cooking time (5 to 35 min). The results from this study are useful for validating thermal lethality of pathogens in poultry products that are cooked via impingement ovens.
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Nummert, Vilve, and Mare Piirsalu. "Separation of ortho Inductive, Resonance and Steric Terms in Alkaline Hydrolysis of Substituted Phenyl Benzoates and Phenyl Tosylates." Collection of Czechoslovak Chemical Communications 67, no. 12 (2002): 1833–57. http://dx.doi.org/10.1135/cccc20021833.
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The second-order rate constants k2 (l mol-1 s-1) for the alkaline hydrolysis of meta-, para- and ortho-substituted phenyl benzoates C6H5CO2C6H4-X and phenyl tosylates 4-CH3-C6H4SO2OC6H4-X in aqueous 5.3 M NaClO4 have been measured spectrophotometrically at various temperatures. The log k values at a single temperature were analysed according to the equations log km,p = log k0 + (ρ)°m,pσ°, log kortho = log k0+ (ρI)orthoσI + (ρR)orthoσR° + δorthoυ and log km,p,ortho = log k0+ (ρI)orthoσI + (ρI)metaσI + (ρI)paraσI + (ρR)orthoσR° + (ρR)metaσR° + (ρR)paraσR° + δorthoυ. In the case of various temperatures, the equation for data processing involved the additional c1(1/T) term and the cross term cm,p(1/T)σ° or c2(1/T)σI and c3(1/T)σR° different for ortho-, meta- and para-substituted derivatives. As the measure of the steric influence from ortho position, the Charton υ values were used. In the case of a single temperature, the sensitivity to the inductive effect of ortho substituents was found to be about 1.7 times (in water 1.5 times) stronger than that of para and meta substituents in both reaction series studied. The variation of the ortho inductive influence with temperature appeared to be more than twice larger than that for para substituents. Compared to water, in aqueous 5.3 M NaClO4 the inductive effect from ortho position was nearly unchanged while the para inductive effect was found to be about 0.13 units of ρI smaller in the case of both reaction series studied, though the polar effects in these reaction series differ about two-fold. Due to different variation of the ortho and para inductive effects with solvent and temperature, the relative increase in the ortho effect was observed when going from water to aqueous 5.3 M NaClO4.
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WARD, MICHELLE, RADHIKA DHINGRA, JUSTIN V. REMAIS, HOWARD H. CHANG, LYNETTE M. JOHNSTON, LEE-ANN JAYKUS, and JUAN LEON. "Associations between Weather and Microbial Load on Fresh Produce Prior to Harvest." Journal of Food Protection 78, no. 4 (April 1, 2015): 849–54. http://dx.doi.org/10.4315/0362-028x.jfp-14-381.
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Contaminated produce causes approximately 1 million cases of foodborne illness and 1 billion dollars in damages to the U.S. economy annually. The environmental conditions, especially weather, that influence the inoculation, proliferation, and dispersal of microbial load on produce are not well understood. Using a mixed models approach, we examined the relationship of temperature and precipitation to microbial indicators of contamination on fresh produce on the farm over a week-long period prior to harvest. Between 2000 and 2002, we assayed for four microbial indicators of contamination (aerobic plate count, Enterococcus, total coliforms, and Escherichia coli) on 10 produce types in 15 fields in the southern United States. The sample collection times varied, with most occurring between January and May. We collected hourly weather data for the corresponding time period and location. Our results indicated that there was a significant association between the average daily temperature (20°C) and both log aerobic plate count (e.g., an increase of 0.074 log CFU/g [standard error {SE}, 0.023] per °C increase in weekly average temperature) and log Enterococcus (e.g., an increase of 0.15 log CFU/g [SE, 0.031] per °C increase in weekly average temperature) for approximately 5 days prior to sample collection. Daily total precipitation was significantly associated with log coliforms on 2 days (~0.11 log CFU/g [SE, 0.06] per mm of precipitation) during the week-long lag period prior to harvest. Our results suggest that microbial indicator concentrations may increase as the temperature increases. Precipitation may have a positive but complex relationship with microbial indicators, as precipitation may create moist conditions conducive to bacterial growth, spread contamination onto the field, or wash contamination off of the plant.
Dissertations / Theses on the topic "Temperature log"
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Fuchs, Sven. "Well-log based determination of rock thermal conductivity in the North German Basin." Phd thesis, Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6780/.
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In sedimentary basins, rock thermal conductivity can vary both laterally and vertically, thus altering the basin’s thermal structure locally and regionally. Knowledge of the thermal conductivity of geological formations and its spatial variations is essential, not only for quantifying basin evolution and hydrocarbon maturation processes, but also for understanding geothermal conditions in a geological setting. In conjunction with the temperature gradient, thermal conductivity represents the basic input parameter for the determination of the heat-flow density; which, in turn, is applied as a major input parameter in thermal modeling at different scales. Drill-core samples, which are necessary to determine thermal properties by laboratory measurements, are rarely available and often limited to previously explored reservoir formations. Thus, thermal conductivities of Mesozoic rocks in the North German Basin (NGB) are largely unknown. In contrast, geophysical borehole measurements are often available for the entire drilled sequence. Therefore, prediction equations to determine thermal conductivity based on well-log data are desirable. In this study rock thermal conductivity was investigated on different scales by (1) providing thermal-conductivity measurements on Mesozoic rocks, (2) evaluating and improving commonly applied mixing models which were used to estimate matrix and pore-filled rock thermal conductivities, and (3) developing new well-log based equations to predict thermal conductivity in boreholes without core control.
Laboratory measurements are performed on sedimentary rock of major geothermal reservoirs in the Northeast German Basin (NEGB) (Aalenian, Rhaethian-Liassic, Stuttgart Fm., and Middle Buntsandstein). Samples are obtained from eight deep geothermal wells that approach depths of up to 2,500 m. Bulk thermal conductivities of Mesozoic sandstones range between 2.1 and 3.9 W/(m∙K), while matrix thermal conductivity ranges between 3.4 and 7.4 W/(m∙K). Local heat flow for the Stralsund location averages 76 mW/m², which is in good agreement to values reported previously for the NEGB. For the first time, in-situ bulk thermal conductivity is indirectly calculated for entire borehole profiles in the NEGB using the determined surface heat flow and measured temperature data. Average bulk thermal conductivity, derived for geological formations within the Mesozoic section, ranges between 1.5 and 3.1 W/(m∙K).
The measurement of both dry- and water-saturated thermal conductivities allow further evaluation of different two-component mixing models which are often applied in geothermal calculations (e.g., arithmetic mean, geometric mean, harmonic mean, Hashin-Shtrikman mean, and effective-medium theory mean). It is found that the geometric-mean model shows the best correlation between calculated and measured bulk thermal conductivity. However, by applying new model-dependent correction, equations the quality of fit could be significantly improved and the error diffusion of each model reduced. The ‘corrected’ geometric mean provides the most satisfying results and constitutes a universally applicable model for sedimentary rocks. Furthermore, lithotype-specific and model-independent conversion equations are developed permitting a calculation of water-saturated thermal conductivity from dry-measured thermal conductivity and porosity within an error range of 5 to 10%.
The limited availability of core samples and the expensive core-based laboratory measurements make it worthwhile to use petrophysical well logs to determine thermal conductivity for sedimentary rocks. The approach followed in this study is based on the detailed analyses of the relationships between thermal conductivity of rock-forming minerals, which are most abundant in sedimentary rocks, and the properties measured by standard logging tools. By using multivariate statistics separately for clastic, carbonate and evaporite rocks, the findings from these analyses allow the development of prediction equations from large artificial data sets that predict matrix thermal conductivity within an error of 4 to 11%. These equations are validated successfully on a comprehensive subsurface data set from the NGB. In comparison to the application of earlier published approaches formation-dependent developed for certain areas, the new developed equations show a significant error reduction of up to 50%.
These results are used to infer rock thermal conductivity for entire borehole profiles. By inversion of corrected in-situ thermal-conductivity profiles, temperature profiles are calculated and compared to measured high-precision temperature logs. The resulting uncertainty in temperature prediction averages < 5%, which reveals the excellent temperature prediction capabilities using the presented approach.
In conclusion, data and methods are provided to achieve a much more detailed parameterization of thermal models.Die thermische Modellierung des geologischen Untergrundes ist ein wichtiges Werkzeug bei der Erkundung und Bewertung tiefliegender Ressourcen sedimentärer Becken (e.g., Kohlenwasserstoffe, Wärme). Die laterale und vertikale Temperaturverteilung im Untergrund wird, neben der Wärmestromdichte und der radiogenen Wärmeproduktion, hauptsächlich durch die Wärmeleitfähigkeit (WLF) der abgelagerten Gesteinsschichten bestimmt. Diese Parameter stellen die wesentlichen Eingangsgrößen für thermische Modelle dar. Die vorliegende Dissertation befasst sich mit der Bestimmung der Gesteins-WLF auf verschiedenen Skalen. Dies umfasst (1) laborative WLF-Messungen an mesozoischen Bohrkernproben, (2) die Evaluierung und Verbesserung der Prognosefähigkeit von Mischgesetzten zur Berechnung von Matrix- und Gesamt-WLF sedimentärer Gesteine, sowie (3) die Entwicklung neuer Prognosegleichungen unter Nutzung bohrlochgeophysikalischer Messungen und multivariater Analysemethoden im NGB. Im Nordostdeutschen Becken (NEGB) wurden für die wichtigsten geothermischen Reservoire des Mesozoikums (Aalen, Rhät-Lias-Komplex, Stuttgart Formation, Mittlerer Buntsandstein) Bohrkerne geothermischer Tiefbohrungen (bis 2.500 m Tiefe) auf Ihre thermischen und petrophysikalischen Eigenschaften hin untersucht. Die WLF mesozoischer Sandsteine schwankt im Mittel zwischen 2,1 und 3,9 W/(m∙K), die WLF der Gesteinsmatrix hingegen im Mittel zwischen 3,4 und 7,4 W/(m∙K). Neu berechnete Werte zur Oberflächenwärmestromdichte (e.g., 76 mW/m², Stralsund) stehen im Einklang mit den Ergebnissen früherer Studien im NEGB. Erstmals im NDB wurde für das mesozoisch/känozoischen Intervall am Standort Stralsund ein in-situ WLF-Profil berechnet. In-situ Formations-WLF, für als potentielle Modelschichten interessante, stratigraphische Intervalle, variieren im Mittel zwischen 1,5 und 3,1 W/(m∙K) und bilden eine gute Grundlage für kleinskalige (lokale) thermische Modelle. Auf Grund der in aller Regel nur eingeschränkt verfügbaren Bohrkernproben sowie des hohen laborativen Aufwandes zur Bestimmung der WLF waren alternative Methoden gesucht. Die Auswertung petrophysikalischer Bohrlochmessungen mittels mathematischer-statistischer Methoden stellt einen lang genutzten und erprobten Ansatz dar, welcher in seiner Anwendbarkeit jedoch auf die aufgeschlossenen Gesteinsbereiche (Genese, Geologie, Stratigraphie, etc.) beschränkt ist. Daher wurde ein leicht modifizierter Ansatz entwickelt. Die thermophysikalischen Eigenschaften der 15 wichtigsten gesteinsbildenden Minerale (in Sedimentgesteinen) wurden statistisch analysiert und aus variablen Mischungen dieser Basisminerale ein umfangreicher, synthetischer Datensatz generiert. Dieser wurde mittels multivariater Statistik bearbeitet, in dessen Ergebnis Regressionsgleichungen zur Prognose der Matrix-WLF für drei Gesteinsgruppen (klastisch, karbonatisch, evaporitisch) abgeleitet wurden. In einem zweiten Schritt wurden für ein Echtdatenset (laborativ gemessene WLF und Standardbohrlochmessungen) empirische Prognosegleichungen für die Berechnung der Gesamt-WLF entwickelt. Die berechneten WLF zeigen im Vergleich zu gemessenen WLF Fehler zwischen 5% und 11%. Die Anwendung neu entwickelter, sowie in der Literatur publizierter Verfahren auf den NGB-Datensatz zeigt, dass mit den neu aufgestellten Gleichungen stets der geringste Prognosefehler erreicht wird. Die Inversion neu berechneter WLF-Profile erlaubt die Ableitung synthetischer Temperaturprofile, deren Vergleich zu gemessenen Gesteinstemperaturen in einen mittleren Fehler von < 5% resultiert. Im Rahmen geothermischer Berechnungen werden zur Umrechnung zwischen Matrix- und Gesamt-WLF häufig Zwei-Komponenten-Mischmodelle genutzt (Arithmetisches Mittel, Harmonische Mittel, Geometrisches Mittel, Hashin-Shtrikman Mittel, Effektives-Medium Mittel). Ein umfangreicher Datensatz aus trocken- und gesättigt-gemessenen WLF und Porosität erlaubt die Evaluierung dieser Modelle hinsichtlich Ihrer Prognosefähigkeit. Diese variiert für die untersuchten Modelle stark (Fehler: 5 – 53%), wobei das geometrische Mittel die größte, quantitativ aber weiterhin unbefriedigende Übereinstimmungen zeigt. Die Entwicklung und Anwendung mischmodelspezifischer Korrekturgleichungen führt zu deutlich reduzierten Fehlern. Das korrigierte geometrische Mittel zeigt dabei, bei deutlich reduzierter Fehlerstreubreite, erneut die größte Übereinstimmung zwischen berechneten und gemessenen Werten und scheint ein universell anwendbares Mischmodel für sedimentäre Gesteine zu sein. Die Entwicklung modelunabhängiger, gesteinstypbezogener Konvertierungsgleichungen ermöglicht die Abschätzung der wassergesättigten Gesamt-WLF aus trocken-gemessener WLF und Porosität mit einem mittleren Fehler < 9%. Die präsentierten Daten und die neu entwickelten Methoden erlauben künftig eine detailliertere und präzisere Parametrisierung thermischer Modelle sedimentärer Becken.
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Whisler, Bruce A. "A qualitative and quantitative analysis of the acoustical effect of cryogenic freezing on brass trumpets." Virtual Press, 2002. http://liblink.bsu.edu/uhtbin/catkey/1238742.
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The purpose of this study was to determine whether deep-cryogenic freezing produces a change in the timbre or playing characteristics of brass trumpets. The experimental procedure consisted of two parts: quantitative analysis and qualitative analysis. For qualitative analysis a panel of four professional trumpet players evaluated five trumpets: four were frozen and re-evaluated, and one served as the experimental control. Analysis of the harmonic spectra of tones from each instrument provided quantitative data. Since previous studies requiring the analysis of musical instrument tones have suffered from a high degree of variation among tones played by human performers, I constructed a mechanical device that could play tones on the test instruments with greater consistency than is possible with live performers.The changes observed in the qualitative and quantitative analyses are very small, and possibly contradictory. The test panel rated all of the instruments higher after they had been frozen, and any actual improvement in the playing characteristics is suspect because the control instrument received the second highest improvement of the five instruments in the study. In the quantitative analysis, I observed some slight changes in the amplitudes of some of the harmonics in the spectral graphs, but I also observed slight variations in some of the harmonics of the control instrument. Inconsistencies in the performance of the electronic equipment used in the study could account for some of the variation. The instrument that showed the most statistically significant improvements was rated significantly higher in intonation after cryogenic processing, but I was unable to measure any frequency changes in the tones the mechanical embouchure played on the test instruments.Although one may not actually be able to measure differences reported in the qualitative analysis, it is not possible to rule out any acoustical change from cryogenic freezing. In fact, in the quantitative measurements, three of the instruments showed changes greater (some positive and some negative) than the "experimental error" seen in the control instrument's measurements. Additionally, one member of the test panel is convinced that cryogenic freezing has improved his instrument significantly, but the other three trumpeters are ambivalent.School of Music
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Hsu, Chuan-liang. "Influence of cooling rate on glass transition temperature and starch retrogradation during low temperature storage /." free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9924889.
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Jacobi, Christoph, Nadja Samtleben, and Gunter Stober. "Meteor radar observations of mesopause region long-period temperature oscillations." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-212263.
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Meteor radar observations of mesosphere/lower thermosphere (MLT) daily temperatures have been performed at Collm, Germany since August 2004. The data have been analyzed with respect to long-period oscillations at time scales of 2–30 days. The results reveal that oscillations with periods of up to 6 days are more frequently observed during summer, while those with longer periods have larger amplitudes during winter. The oscillations may be considered as the signature of planetary waves. The results are compared with analyses from radar wind measurements. Moreover, the temperature oscillations show considerable year-to-year variability. In particular, amplitudes of the quasi 5-day oscillation have increased during the last decade, and the quasi 10-day oscillations are larger if the equatorial stratospheric winds are eastward.
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Aguilar, Jaramillo Andrea Elizabeth. "Implicación de los genes de la familia RAV en el desarrollo floral." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/393982.
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La floración es probablemente el proceso más importante en el desarrollo de la
planta, ya que la perpetuación de las especies vegetales depende de ella. En Arabidopsis
thaliana, la inducción floral está controlada por varias rutas genéticas que responden a
estímulos ambientales y endógenos. En nuestro laboratorio se han identificado los genes
TEMPRANILLO (TEM) como represores de la floración tanto en condiciones inductivas
de día largo (LD, 16 horas de luz) como no inductivas de día corto (SD, 8 horas de luz).
Las proteínas TEM pertenecen a una familia de factores de transcripción llamada RAV,
que se caracterizan por contener dos dominios de unión al DNA, que son los dominios
APETALA2 (AP2) y B3. En Arabidopsis esta familia está compuesta por 6 genes. En
LD, la ruta del fotoperiodo induce la floración principalmente a través de la activación
del gen FLOWERING LOCUS T (FT), mientras que en SD la floración depende
principalmente de la acumulación de giberelinas (GAs). TEM1 y TEM2 retrasan la
floración en ambas condiciones al reprimir directamente la expresión de los genes FT,
GA3OXIDASE 1 (GA3OX1) y GA3OX2, siendo los dos últimos genes responsables de la
biosíntesis de la GA bioactiva GA4. Por tanto, TEM1 y TEM2 controlan el tiempo de
floración a través de al menos dos de las rutas genéticas que controlan la inducción
floral: la del fotoperíodo (Castillejo & Pelaz, 2008) y la de las GAs (Osnato et al, 2012).
El objetivo de este trabajo ha sido profundizar en el papel de los genes TEM en
otras rutas genéticas implicadas en el control de la floración y en otros procesos de
desarrollo en Arabidopsis thaliana.
Existe una ruta genética que responde a la edad de la planta y que evita que ésta
florezca en su etapa juvenil. Primero se produce la transición de la etapa vegetativa
juvenil a la adulta y después la inducción floral. Los microRNAs miR156 y miR172
están implicados en la regulación de estas transiciones entre las fases del desarrollo de
la planta (Huijser & Schmid, 2011). miR156 mantiene la fase juvenil y retrasa la
transición floral (Wu & Poeting, 2006; Wu et al, 2009), mientras que los genes diana de
miR156 SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) y miR172
promueven la transición a la fase adulta y la inducción floral. Nuestros resultados
muestran que los genes TEM están involucrados en varias etapas de la ruta de la edad,
ya que regulan positivamente a miR156 y negativamente a varios genes SPL y miR172,
retrasando así la floración. Por tanto, los genes TEM desempeñan un papel clave en la respuesta a la edad de la planta (Capítulo 1; Aguilar-Jaramillo et al., manuscrito en
preparación).
Por otro lado, cuando las plantas crecen en LD a bajas temperaturas ambientales
de 16ºC, la floración se retrasa respecto a 22°C. Nuestros resultados muestran que los
genes TEM actúan como represores de FT y TWIN SISTER OF FT (TSF) a 16°C. Un
gen que juega un papel clave en la respuesta a las bajas temperaturas ambientales es
SHORT VEGETATIVE PHASE (SVP), cuyos mutantes son insensibles a los cambios de
temperatura y florecen pronto tanto a temperaturas cálidas como frescas. Hemos
descubierto que SVP regula positivamente la expresión de TEM2 a 16ºC en condiciones
de LD y controla la floración a través de TEM2, pero también de manera independiente
mediante la represión directa de FT a bajas temperaturas ambientales (Capítulo 2;
Marín-González et al, 2015).
Además, hemos descubierto la participación de TEM en otro proceso del
desarrollo, la iniciación de los tricomas. Los tricomas son protrusiones epidérmicas que
protegen a la planta de la pérdida de agua, de insectos y de las radiaciones ultravioletas.
Hemos descubierto que los genes TEM controlan la iniciación de los tricomas mediante
la represión directa de los genes epidérmicos que promueven su iniciación y, lo que es
más interesante, a través del control de la acumulación y distribución de las GAs en el
mesófilo. Esta función de los genes TEM desvela el papel clave de una capa celular, el
mesófilo, en la diferenciación celular de los tricomas en la capa exterior adyacente, la
epidermis (Capítulo 3; Matías-Hernández et al, 2016).Flowering is probably the most important process in plant development since the perpetuation of the species depends on it. In Arabidopsis thaliana, floral induction is controlled by several genetic pathways that respond to environmental and endogenous stimuli. In our laboratory we have identified the TEMPRANILLO (TEM) genes as flowering repressors under both inductive long-day (LD, 16 hours of light) and noninductive short-day (SD, 8 hours of light) conditions. The TEM proteins belong to a family of transcription factors called RAV, characterized by the presence of two DNA binding domains, the APETALA2 (AP2) and B3 domains. In Arabidopsis this family is composed of 6 genes. Under LD the photoperiod pathway induces flowering mainly through activation of FLOWERING LOCUS T (FT), while under SD flowering depends mainly on the accumulation of gibberellins (GAs). TEM1 and TEM2 delay flowering under both conditions by directly repressing the expression of the FT, GA 3-OXIDASE 1 (GA3OX1) and GA3OX2 genes, the latter two genes being responsible for the biosynthesis of bioactive GA4. Therefore, TEM1 and TEM2 control flowering time through at least two of the genetic pathways that control floral induction: the photoperiod (Castillejo & Pelaz, 2008) and the GA pathway (Osnato et al, 2012). In this PhD thesis we aimed to deepen the role of TEM genes in other genetic pathways controlling flowering and other developmental processes in Arabidopsis thaliana. There is a genetic pathway that responds to the age of the plant and prevents flowering at the juvenile phase. First there is a transition from the juvenile to the adult vegetative stage and then floral induction occurs. The microRNAs miR156 and miR172 are involved in the regulation of these phase transitions of plant development (Huijser & Schmid, 2011). MiR156 maintains the juvenile phase and delays the floral transition (Wu & Poeting, 2006; Wu et al, 2009), while miR156-target SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) genes and miR172 promote the transition to adulthood and floral induction. Our results show that TEM genes are involved in regulating various stages of the age-dependent pathway as they positively regulate miR156 and negatively regulate several SPL genes and miR172, thus delaying flowering. Therefore, TEM genes play a key role in responding to the age of the plant (Chapter 1, Aguilar-Jaramillo et al., manuscript in preparation). On the other hand, when Arabidopsis plants grow under LD at low ambient temperatures of 16°C, flowering is delayed relative to 22°C. Our results show that TEM genes act as repressors of FT and TWIN SISTER OF FT (TSF) at 16°C. A gene that plays a key role in the response to low ambient temperatures is SHORT VEGETATIVE PHASE (SVP). svp mutants are insensitive to temperature changes and flower early both under warm and cool temperatures. We have found that SVP positively regulates TEM2 expression at 16 °C under LD conditions, controlling flowering through TEM2 but also independently of TEM2 by directly repressing FT at low temperatures (Chapter 2; Marín-González et al, 2015). In addition, we have discovered the involvement of TEM in another developmental process, the initiation of trichomes. Trichomes are epidermal protrusions that protect the plant from water loss, insects and ultraviolet radiation. We show that TEM genes control the initiation of trichomes by directly repressing the epidermal genes that promote trichome initiation and, more interestingly, by controlling the accumulation and distribution of GAs in the mesophyll. This function of TEM genes reveals a key role of a cell layer, the mesophyll, in trichome differentiation in the outer adjacent cell layer, the epidermis (Chapter 3; Matías-Hernández et al, 2016).
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Fernandez, Juan Manuel Carvajalino. "Tolerância ao congelamento em algumas espécies de anuros de América do Sul: mecanismos e estratégias." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-18102017-131508/.
Full textAbstract:
Os limites geográficos que marcam o risco de congelamento são determinantes na biodiversidade de anfíbios. Os mecanismos fisiológicos envolvidos na preparação e reação aos eventos de temperatura extrema são específicos e dependem da previsibilidade e repetitividade destes eventos. Na América do Sul, existem regiões com risco de congelamento para os anfíbios, contudo pouco se conhece da tolerância ao congelamento em espécies endêmicas deste continente. O doutorado foi elaborado em locais com reportes de congelamento na Argentina e o Brasil, usando como modelo as espécies Alsodes gargola, Bokermanohyla gouveai, Dendrosophus minutus, D. microps, Hypsiboas latistriatus, H. polytaenius, Melanophryniscus moreirae, Pleurodema bufoninum, Ologygon brieni, Scinax duartei e S. hayii, avaliando exposição potencial ao congelamento em refúgios termais, sobrevivência a temperatura congelante, mudanças em moléculas com função crioprotetora (colesterol, glicose, proteínas, triglicérides, ureia) e crescimento de gelo corporal. Dentro deste contexto, a minha hipótese geral foi que existem anfíbios que sobrevivem ao congelamento na América do sul e que estas espécies presentam mecanismos de resposta fisiológica que deveriam variar entre espécies em um evento de congelamento controlado. No decorrer do doutorado esta hipótese foi corroborada, encontrando sobrevivência a temperatura congelantes nas especies A. gargola, B. gouveai, D. microps, H. latistriatus, H. polytaenius, M. moreirae, P. bufoninum, S. duartei e S. hayii, sendo que existe uma amplia variedade de estratégias fisiológicas para fazer frente ás baixas temperaturas. Entre as espécies anteriormente reportadas, definiu-se que D. microps, H. polytaenius, P. bufoninum, S. duartei e S. hayii, são tolerantes ao congelamento devido a que apresentarem tanto acumulo de crioprotectores como crescimento de gelo corporal durante a exposição a baixas temperaturas. Por outro lado usando analises filogenéticos, conseguiu-se reforçar a hipóteses que a tolerância ao congelamento é convergente ao longo da historia evolutiva dos anfíbios, acontecendo independentemente em vários clados. As novas descobertas sobre a riqueza fisiologia no nível de adaptações frente ao congelamento em América do Sul são apenas pequenas amostras do que potencialmente pode ser achada pensando na biodiversidade existente neste continente, logo a presente tese, é só um incentivo para futuros trabalho na áreaThe geographical boundaries that mark the risk of freezing are determinants for amphibian biodiversity. The physiological mechanisms involved in the preparation and reaction to extreme temperature events are specific and depend on the predictability and repeatability of these events. In South America, there are regions with freezing risk for amphibians, however little is known about the freezing tolerance in endemic species to this continent. The present doctoral dissertation was prepared in places with freezing reports in Argentina and Brazil, using as biological models the species Alsodes gargola, Bokermanohyla gouveai, Dendrosophus minutus, D. microps, Hypsiboas latistriatus, H. polytaenius, Melanophryniscus moreirae, Pleurodema bufoninum, Ologygon brieni, Scinax duartei and S. hayii, evaluating potential exposure to freezing in thermal refuges, survival to freezing temperature, changes in cryoprotectant molecules (cholesterol, glucose, proteins, triglycerides, urea) and body ice growth. Within this context, my general hypothesis was that there are amphibians that survive freezing in South America and that these species present physiological mechanisms that should vary among species in a controlled freezing event. In the course of my doctorate, this hypothesis was confirmed, finding survival to freezing temperature in the species A. gargola, B. gouveai, D. microps, H. latistriatus, H. polytaenius, M. moreirae, P. bufoninum, S. duartei and S. hayii, being a wide variety of physiological strategies to protect the animals to the low temperatures. Among the previously reported species, D. microps, H. polytaenius, P. bufoninum, S. duartei, S. hayii, were defined as freezing tolerant because they exhibit both accumulation of cryoprotectants and body ice growth during freeze exposure. On the other hand using phylogenetic analyzes, it was possible to reinforce the hypotheses that the freezing tolerance strategy is convergent throughout the evolutionary history of the amphibians, happening independently in several clades. The new findings about physiological richness at the level of adaptations to freezing in South America are only small samples of what can be found within the biodiversity existing on this continent, so the present thesis is only an incentive for future work in the area
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Samtleben, Nadja, and Christoph Jacobi. "Long-period oscillations derived from mesosphere/lower thermosphere meteor radar temperature measurements." Universität Leipzig, 2015. https://ul.qucosa.de/id/qucosa%3A16649.
Full textAbstract:
Using measurements, derived from a meteor radar in Collm (51.3°N, 13°E), the mesopause region is analyzed with respect to the temperature distribution at an altitude of 90 km over a period of 10 years. The analyzed period lasts from 2005 till 2013. Based on these measurements, the typical temperature seasonal cycle of the mesopause region can be observed. The temperature reaches its minimum of about 130 K in summer and its maximum of about 220 K in winter. At this altitude, also strong day-today- fluctuations of up to 35 K exist, which are probably partly induced by planetary waves. Shorter-period oscillations with a period between 2 and 6 days have maximum amplitudes during summer, while longer-period oscillations with a period between 7 and 20 days maximize during winter. During the measurement period the amplitudes of oscillations with periods between 4 and 6 days, which may be attributed to the quasi-5-day-wave, increase with time.Auf der Grundlage von Messungen eines Meteorradars in Collm (51.3°N, 13°E), die in einer Höhe von 90 km erfolgten, was in etwa der Mesopause entspricht, wird die Temperatur hinsichtlich ihres Jahresganges und insbesondere ihrer Variationen in einem Messzeitraum von 10 Jahren analysiert. Der analysierte Zeitraum erstreckt sich von 2005 bis 2013. Anhand der Daten kann man den typischen Jahresgang der Temperatur in der Mesopausenregion erkennen. Die Temperatur erreicht im Sommer das Minimum bei etwa 130 K und im Winter das Maximum bei etwa 220 K. Zudem treten starke Tag-zu-Tag-Fluktuationen auf, die im Maximum 35 K betragen. Diese werden vermutlich durch planetare Wellenaktivität der Atmosphäre hervorgerufen. Hierbei spielen im Sommer die kurzwelligen und im Winter die langwelligen Oszillationen, letztere mit Perioden größer 7 Tage, die wesentliche Rolle. Ferner sind innerhalb des Messzeitraums zunehmende Amplituden von Oszillationen mit Perioden zwischen 4 und 6 Tagen (quasi 5-Tage-Welle) zu erkennen.
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Bonthron, Björn, and Christian Jonsson. "Geogrids in cold climate : Temperature controlled tensile tests & Half-scale installation tests at different temperatures." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-63204.
Full textAbstract:
Due to the findings of extensive damage on geogrids used in a road embankment in northern Sweden, the Swedish Transport Administration (TRV) started to investigate the reason of these damages. Since the geogrids were installed at low temperature, below 0°C, it was suspected that the damages were connected the low temperature. To analyse whether low temperatures have an influence on the extent of installation damages, both a half-scale setup and temperature controlled tensile tests have been carried out on geogrids. In total five different types of geogrids have been tested; 3 extruded polypropylene geogrids, 1 woven PET geogrid, and 1 welded PET geogrid. All geogrids had an aperture size of approximately 35 mm and specified tensile strength of approximately 40 kN/m. The Half-scale tests was conducted by building a small road embankment inside a freeze container, at the Luleå University of Technology (LTU). The embankment contained crushed aggregate, type 0-70 mm, and geogrids. The purpose of the half-scale test was to simulate installation of geogrids at different temperatures and thereby investigate whether low temperatures have an influence on the rate of installation damages. The half-scale test was done for each type of geogrid at the temperatures: +20°C, -20°C and -30°C. First, the geogrid was covered by 150 mm of crushed aggregate. Then a vibratory plate (160 kg) was used to compact the crushed aggregate. After each installation, the crushed aggregate was removed carefully by vacuum suction. The geogrid was removed and then analysed by visual control and tensile tests conducted according to ISO 10319:2008 (wide width tensile test). Results from the half-scale tests indicate that 2 out of 5 of the tested geogrids were affected by the testing procedure. The results indicate that: - one of the geogrids of polyprophylene (here referred to as G2) was more damaged at lower temperatures compared to installation at +20° C. - the geogrid of woven PET (here referred to as G5) was less damaged at lower temperatures compared to installation at +20° C. Results for the other geogrids are either inconsistent or shows no significant variation of the measured parameters as function of temperature. Hence, these results cannot be interpreted as damage during installation. Temperature controlled tensile tests were done by tensile testing single strands from the geogrids to failure, inside a temperature controlled chamber. The purpose of these tests was to investigate how the strength properties of the geogrids are affected by low temperature. The test was repeated 5 times for each geogrid and temperature (+20°C, 0°C, -10°C and -20°C). Force and strain was measured during the tests. The results from the temperature controlled tensile tests show that the maximum strain decreases with lower temperature for all tested geogrids. The maximum strain decreased by 16% - 49% when the temperature dropped from +20°C to -20°C. The results show that the tensile strength increases with lower temperature for all tested geogrids except for the welded PET geogrid (here referred to as G1). For G1 the tensile strength decreased by approximately 7% at a temperature drop from +20°C to -20°C. For the woven PET geogrid (G5) and the polypropylene geogrids (G2-G3) the tensile strength increased between 13%-45% at a temperature drop from +20°C to -20°C. The E-modulus increased at lower temperature for all tested geogrids. The secant E-modulus at 2% strain increased by 13%-71% at a temperature drop from +20°C to -20°C. Summarized conclusions from the tests: Strength properties changed for all tested geogrids as the temperature decreased. All tested geogrids got stiffer at lower temperatures. The magnitude of the effects is different for different geogrids. The tensile strength increased with lower temperature for all tested geogrids except for the welded PET geogrid, which got lower tensile strength at lower temperature. The half-scale test indicates that the amount of installation damages at geogrids can be dependent of the temperature at installation. However, these indications can only be seen at two out of five tested geogrids. The effect cannot be connected to a specific step in the installation procedure and cannot be explained by the results from the temperature controlled tensile tests. The results from the half-scale test have a statistically low reliability since only one installation for each temperature and geogrid type was done. The compaction equipment used during the test was small, and had low compaction energy compared to a vibratory roller compactor commonly used in construction work. With respect to the discussion above, further studies should be focusing on developing the half-scale test. It is suggested that the test is scaled up to a full-scale test in order to simulate a real installation as close as possible. The test should also be conducted several times for each geogrid at each temperature in order to enable statistical analyses.
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Matthews, Jason E. "Thermoelectric and Heat Flow Phenomena in Mesoscopic Systems." Thesis, University of Oregon, 2011. http://hdl.handle.net/1794/12108.
Full textAbstract:
xvii, 189 p. ： ill. (some col.)Low-dimensional electronic systems, systems that are restricted to single energy levels in at least one of the three spatial dimensions, have attracted considerable interest in the field of thermoelectric materials. At these scales, the ability to manipulate electronic energy levels offers a great deal of control over a device's thermopower, that is, its ability to generate a voltage due to a thermal gradient. In addition, low-dimensional devices offer increased control over phononic heat flow. Mesoscale geometry can also have a large impact on both electron and phonon dynamics. Effects such as ballistic transport in a two-dimensional electron gas structure can lead to the enhancement or attenuation of electron transmission probabilities in multi-terminal junctions. The first half of this dissertation investigates the transverse thermoelectric properties of a four-terminal ballistic junction containing a central symmetry-breaking scatterer. It is believed that the combined symmetry of the scatterer and junction is the key component to understanding non-linear and thermoelectric transport in these junctions. To this end, experimental investigations on this type of junction were carried out to demonstrate its ability to generate a transverse thermovoltage. To aid in interpreting the results, a multi-terminal scattering-matrix theory was developed that relates the junction's non-linear electronic properties to its thermoelectric properties. The possibility of a transverse thermoelectric device also motivated the first derivation of the transverse thermoelectric efficiency. This second half of this dissertation focuses on heat flow phenomena in InAs/InP heterostructure nanowires. In thermoelectric research, a phononic heat flow between thermal reservoirs is considered parasitic due to its minimal contribution to the electrical output. Recent experiments involving heterostructure nanowires have shown an unexpectedly large heat flow, which is attributed in this dissertation to an interplay between electron-phonon interaction and phononic heat flow. Using finite element modeling, the recent experimental findings have provided a means to probe the electron-phonon interaction in InAs nanowires. In the end, it is found that electron-phonon interaction is an important component in understanding heat flow at the nanoscale. This dissertation includes previously unpublished co-authored material.
Committee in charge: Dr. Richard Taylor， Chair； Dr. Heiner Linke， Advisor； Dr. David Cohen， Member； Dr. John Toner， Member； Dr. David Johnson， Outside Member
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Falquetto, Paula Lyra 1987. "Desenvolvimento de uma bomba de calor doméstica para secagem de hortelã." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255768.
Full textAbstract:
Orientador: Vivaldo Silveira JuniorDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-21T19:48:08Z (GMT). No. of bitstreams: 1 Falquetto_PaulaLyra_M.pdf: 2346097 bytes, checksum: 46b1d8899428de4582aaf03fa022871c (MD5) Previous issue date: 2013
Resumo: Diversos tipos de secagem tem sido utilizados para produtos termossensiveis. O proposito fundamental e a reducao dos custos de transporte, estocagem e o aumento da vida util. Ao mesmo tempo, ha um crescente interesse dos consumidores no uso de ervas e especiarias pelo sabor diferenciado nos alimentos preparados com as mesmas. Em secadores convencionais, o tratamento do ar resulta em temperaturas muito mais altas que a ambiente e umidades absolutas mais baixas, proporcionando maior perda de compostos responsaveis pela cor e sabor, entre outros, durante o processo. Em vista disso, o trabalho teve como objetivos o desenvolvimento e avaliacao de um sistema de tratamento de ar, baseado em uma bomba de calor que produz um ar a baixas temperaturas e pressao de vapor de agua, alimentando um gabinete de bandejas para uso domestico com adaptacao de um refrigerador comercial. Os ensaios foram realizados a pressao atmosferica dentro da cabine. Apos o tratamento do ar (desumidificacao do ar e posterior aquecimento, realizados pela bomba de calor), se obteve uma diferenca das condicoes do ar em comparacao ao ar ambiente de entrada de 22 a 26 oC na temperatura e de 36 a 69% da umidade relativa. O equipamento apresentou bom desempenho na secagem da hortela, produto escolhido para os ensaios, mostrando pouca diferenca na coloracao em relacao a amostra in natura. O tempo de secagem foi de aproximadamente 4 horas, quando se atingiu a umidade do produto desejada, em torno de 6%. O consumo energetico do equipamento no periodo do ensaio ficou em torno de 2 kWh para uma quantidade de 25 g de materia seca
Abstract: Different types of drying are being used for thermosensitive products. The fundamental purpose is the reduction of transportation and storage costs, and increasing of shelf life. At the same time, there is a growing consumer interest in the use of herbs and spices because of the differentiated flavor in distinct foods prepared with them. In conventional dryers air treatment results in higher temperatures that the ambient and lower absolute humidity providing greater loss of compounds responsible for the color and flavor among others during the process. This work had the objective of development and evaluation of an air treatment system, based on a heat pump that operates at low temperatures, feeding a tray cabinet for domestic use with adaptation of a commercial refrigerator. The tests were a source at atmospheric pressure inside the cabin. After treatment of the air (air dehumidification and subsequent heating was done by heat pump), obtaining a difference of air conditions of 22 to 26 °C in temperature and 36 to 69% of moisture with relation to ambient air (input air). The equipment presented good performance in mint drying, the product chosen for the tests, showing differences in coloring low in relation to the fresh sample. The drying time was approximately 4 hours when it has reached the desired product moisture around 6%. The energy consumption of equipment around the time of the test was around 2 kWh for a quantity of 25 g of dry matter
Mestrado
Engenharia de Alimentos
Mestra em Engenharia de Alimentos
Books on the topic "Temperature log"
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Staff, Journals for All. Log Temperature: Temperature Log. Independently Published, 2017.
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Staff, Journals for All. Food Temperature Log: Temperature Log. Independently Published, 2017.
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Staff, Journals for All. Refrigerator Temperature Log: Temperature Log. Independently Published, 2017.
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Staff, Journals for All. Medication Temperature Log: Temperature Log. Independently Published, 2017.
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Staff, Journals for All. Restaurant Temperature Log: Temperature Log. Independently Published, 2017.
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Staff, Journals for All. Vaccine Temperature Log: Temperature Log. Independently Published, 2017.
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Staff, Journals for All. Cooler Temperature Log: Temperature Log. Independently Published, 2017.
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Staff, Journals for All. Room Temperature Log: Temperature Log. Independently Published, 2017.
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Staff, Journals for All. Dishwasher Temperature Log: Temperature Log. Independently Published, 2017.
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Staff, Journals for All. Pharmacy Temperature Log: Temperature Log. Independently Published, 2017.
Find full textBook chapters on the topic "Temperature log"
1
Bateman, Richard M. "Temperature Logging." In Cased-Hole Log Analysis and Reservoir Performance Monitoring, 113–28. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-017-0977-4_8.
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Bateman, Richard M. "Temperature Logging." In Cased-Hole Log Analysis and Reservoir Performance Monitoring, 105–22. New York, NY: Springer New York, 2014. http://dx.doi.org/10.1007/978-1-4939-2068-6_8.
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Matandirotya, Newton R., Dirk P. Cilliers, Roelof P. Burger, Christian Pauw, and Stuart J. Piketh. "Risks of Indoor Overheating in Low-Cost Dwellings on the South African Lowveld." In African Handbook of Climate Change Adaptation, 1583–600. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-45106-6_123.
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AbstractThe South African Lowveld is a region of land that lies between 150 and 2000 m above sea level. In summer the region is characterized by the maximum mean daily ambient temperature of 32 °C. The purpose of the study was to characterize indoor thermal environments in low-cost residential dwellings during summer seasons as climate is changing. Indoor and ambient air temperature measurements were performed at a 30-min temporal resolution using Thermochron iButtons in the settlement of Agincourt. 58 free running low-cost residential dwellings were sampled over the summer seasons of 2016 and 2017. Complementary ambient air temperature data were sourced from the South African Weather Service (SAWS). Data were transformed into hourly means for further analysis. It was found that hourly maximum mean indoor temperatures ranged between 27 °C (daytime) and 23 °C (nighttime) for both living rooms and bedrooms in summer 2016 while in 2017, maximum mean indoor temperatures ranged between 29 °C (daytime) and 26 °C (nighttime) in living rooms and bedrooms. Pearson correlations showed a positive association between indoor and ambient temperatures ranging between r = 0.40 (daytime) and r = 0.90 (nighttime). The association is weak to moderate during daytime because occupants apply other ventilation practices that reduce the relationship between indoor and ambient temperatures. The close association between nighttime ambient and indoor temperature can also be attributed to the effect of urban heat island as nighttime ambient temperature remain elevated; thus, influencing indoor temperatures also remain high. These findings highlight the potential threat posed by a rise in temperatures for low-cost residential dwellings occupants due to climate change. Furthermore, the high level of sensitiveness of dwellings to ambient temperature changes also indicates housing envelopes that have poor thermal resistance to withstand the Lowveld region’s harsh extreme heat conditions, especially during summer. The study findings suggest that a potential risk of indoor overheating exists in low-cost dwellings on the South African Lowveld as the frequency and intensity of heat waves rise. There is therefore a need to develop immediate housing adaptation interventions that mitigate against the projected ambient temperature rise for example through thermal insulation retrofits on the existing housing stock and passive housing designs for new housing stock.
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Reiners, Peter W., Todd A. Ehlers, and Peter K. Zeitler. "1. Past, Present, and Future of Thermochronology." In Low-Temperature Thermochronology:, edited by Peter W. Reiners and Todd A. Ehlers, 1–18. Berlin, Boston: De Gruyter, 2005. http://dx.doi.org/10.1515/9781501509575-003.
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Tagami, Takahiro, and Paul B. O’Sullivan. "2. Fundamentals of Fission-Track Thermochronology." In Low-Temperature Thermochronology:, edited by Peter W. Reiners and Todd A. Ehlers, 19–48. Berlin, Boston: De Gruyter, 2005. http://dx.doi.org/10.1515/9781501509575-004.
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Donelick, Raymond A., Paul B. O’Sullivan, and Richard A. Ketcham. "3. Apatite Fission-Track Analysis." In Low-Temperature Thermochronology:, edited by Peter W. Reiners and Todd A. Ehlers, 49–94. Berlin, Boston: De Gruyter, 2005. http://dx.doi.org/10.1515/9781501509575-005.
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Tagami, Takahiro. "4. Zircon Fission-Track Thermochronology and Applications to Fault Studies." In Low-Temperature Thermochronology:, edited by Peter W. Reiners and Todd A. Ehlers, 95–122. Berlin, Boston: De Gruyter, 2005. http://dx.doi.org/10.1515/9781501509575-006.
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Harrison, T. Mark, and Peter K. Zeitler. "5. Fundamentals of Noble Gas Thermochronometry." In Low-Temperature Thermochronology:, edited by Peter W. Reiners and Todd A. Ehlers, 123–50. Berlin, Boston: De Gruyter, 2005. http://dx.doi.org/10.1515/9781501509575-007.
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Reiners, Peter W. "6. Zircon (U-Th)/He Thermochronometry." In Low-Temperature Thermochronology:, edited by Peter W. Reiners and Todd A. Ehlers, 151–80. Berlin, Boston: De Gruyter, 2005. http://dx.doi.org/10.1515/9781501509575-008.
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Shuster, David L., and Kenneth A. Farley. "7. 4He/3He Thermochronometry: Theory, Practice, and Potential Complications." In Low-Temperature Thermochronology:, edited by Peter W. Reiners and Todd A. Ehlers, 181–204. Berlin, Boston: De Gruyter, 2005. http://dx.doi.org/10.1515/9781501509575-009.
Full textConference papers on the topic "Temperature log"
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Thanapitak, Surachoke, Phumin Kirawanich, Decha Wilairat, and Pongsathorn Sedtheethorn. "Temperature independent log domain filter." In 2013 13th International Symposium on Communications and Information Technologies (ISCIT). IEEE, 2013. http://dx.doi.org/10.1109/iscit.2013.6645860.
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Fakheri, Ahmad. "Log Mean Temperature Correction Factor: An Alternative Representation." In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-39595.
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The Log Mean Temperature Difference (LMTD) correction factor, F, is traditionally expressed in terms of two non-dimensional parameters P=t2−t1T1−t1, and R=T1−T2t2−t1 in form of charts as the underlying equations are complicated. F shows strong functional dependence on both P and R, reducing the accuracy of reading the charts particularly in the steep regions. In this study it is shown that the LMTD correction factor F, can be expressed in terms of two new variables, φ=(T1−T2)2+(t2−t1)22[(T1+T2)−(t1+t2)] and ρ=T1−t2T2−t1. Expressed in terms of these variables, F correlations and charts are much better behaved. Furthermore, it is shown that for the shell and tube and cross flow of heat exchangers, over a wide range of operating conditions of practical interest (0.5 ≤ ρ ≤ 1.0), F can be approximated as a function of a single variable function φ, to within 4% accuracy.
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Brady, J. L., B. A. Watson, D. W. Warner, R. J. North, D. M. Sommer, J. L. Colson, R. L. Kleinberg, and A. Sezginer. "Improved Production Log Interpretation in Horizontal Wells Using a Combination of Pulsed Neutron Logs, Quantitative Temperature Log Analysis, Time Lapse LWD Resistivity Logs and Borehole Gravity." In SPE Western Regional Meeting. Society of Petroleum Engineers, 1998. http://dx.doi.org/10.2118/46222-ms.
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Brady, J. L., B. A. Watson, D. W. Warner, R. J. North, D. M. Sommer, J. L. Colson, R. L. Kleinberg, D. S. Wolcott, and A. Sezginer. "Improved Production Log Interpretation in Horizontal Wells Using a Combination of Pulsed Neutron Logs, Quantitative Temperature Log Analysis, Time Lapse LWD Resistivity Logs and Borehole Gravity." In SPE International Oil and Gas Conference and Exhibition in China. Society of Petroleum Engineers, 1998. http://dx.doi.org/10.2118/48851-ms.
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Walbe, K. A., E. M. Rothman, Richard Stollar, and Perry Harris. "Variations in Temperature Log Response Based on Tool Sensor Location and Logging Sequence." In SPE Eastern Regional Meeting. Society of Petroleum Engineers, 1993. http://dx.doi.org/10.2118/26900-ms.
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Belgiovane, Domenic, Chi-Chih Chen, and Joel T. Johnson. "Conical log spiral antenna development for the UWBRAD ice sheet internal temperature sensing." In 2016 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting. IEEE, 2016. http://dx.doi.org/10.1109/aps.2016.7696619.
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Asif, Adnan Bin, Jon Hansen, AbdulMuqtadir Khan, and Mohamed Sheshtawy. "Integration of Post-Fracturing Spectral Noise Log, Temperature Modeling, and Production Log Diagnoses Water Production and Resolves Uncertainties in Openhole Multistage Fracturing." In SPE Middle East Oil & Gas Show and Conference. SPE, 2021. http://dx.doi.org/10.2118/204668-ms.
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Abstract Hydrocarbon development from tight gas sandstone reservoirs is revolutionizing the current oil and gas market. The most effective development strategy for ultralow- to low-permeability reservoirs involves multistage fracturing. A cemented casing or liner completed with the plug-and-perf method allows nearly full control of fracture initiation depth. In uncemented completions equipped with fracturing sleeves and packers, clearly identifying the fracture initiation points is difficult due to lack of visibility behind the completion and long openhole intervals between packers. Also, the number of fractures initiated in each treatment is uncertain. A lateral was completed with access to 3,190 ft of openhole section across five fracturing stages in a high-temperature and high-pressure tight-gas interval. All stages were successfully stimulated, fracture cleanup flowback was conducted, and entry ports were milled out. A high-definition spectral noise log (SNL) was then conducted along with numerical temperature modeling. Additional logging was done with a set of conventional multiphase sensors. A multi-array production log suite was also performed. Finally, the bottom four stages were isolated with a high-temperature isolation plug based on the integrated diagnosis. The SNL helped to analyze the isolation packer integrity behind the liner. The initiation of multiple fractures was observed, with as many as nine fractures seen in a single-stage interval. A correlation was found between the openhole interval length and the number of fractures. A correlation of fracture gradient (FG) and initiation depths was made for the lateral in a strike-slip fault regime. The fractures were initiated at depths with low calculated FG, confirming the conventional understanding and increasing confidence in rock property calculations from openhole log data. SNL and temperature modeling aided quantitative assessment of flowing fractures and stagewise production behind the liner. Multi-array production logging results quantified the flow and flow profile inside the horizontal liner. The production flow assessments from both techniques were in good agreement. The integration of several datasets was conducted in a single run, which provided a comprehensive understanding of well completion and production. High water producing intervals were isolated. Downstream separator setup after the isolation showed a water cut reduction by 95%. The integration of the post-fracturing logs with the openhole logs and fracturing data is unique. The high-resolution SNL provided valuable insight on fracture initiation points and the integrity of completion packers. Fracturing efficiency, compared to the proppant placed, provides treatment optimization for similar completions in the future.
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Ghalem, Salim, Amr Mohamed Serry, Ali Al-felasi, Ahmed Berrim, Osama Mohamed Keshtta, Maxim Filenev, Elyes Draoui, et al. "Innovative Logging Tool Using Noise Log and High Precision Temperature Help to Diagnoses Complex Problems." In Abu Dhabi International Petroleum Conference and Exhibition. Society of Petroleum Engineers, 2012. http://dx.doi.org/10.2118/161712-ms.
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Syahputra, A. "Oil Saturation Log Prediction Using Neural Network in New Steamflood Area." In Digital Technical Conference. Indonesian Petroleum Association, 2020. http://dx.doi.org/10.29118/ipa20-g-307.
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Surveillance is very important in managing a steamflood project. On the current surveillance plan, Temperature and steam ID logs are acquired on observation wells at least every year while CO log (oil saturation log or SO log) every 3 years. Based on those surveillance logs, a dynamic full field reservoir model is updated quarterly. Typically, a high depletion rate happens in a new steamflood area as a function of drainage activities and steamflood injection. Due to different acquisition time, there is a possibility of misalignment or information gaps between remaining oil maps (ie: net pay, average oil saturation or hydrocarbon pore thickness map) with steam chest map, for example a case of high remaining oil on high steam saturation interval. The methodology that is used to predict oil saturation log is neural network. In this neural network method, open hole observation wells logs (static reservoir log) such as vshale, porosity, water saturation effective, and pay non pay interval), dynamic reservoir logs as temperature, steam saturation, oil saturation, and acquisition time are used as input. A study case of a new steamflood area with 16 patterns of single reservoir target used 6 active observation wells and 15 complete logs sets (temperature, steam ID, and CO log), 19 incomplete logs sets (only temperature and steam ID) since 2014 to 2019. Those data were divided as follows ~80% of completed log set data for neural network training model and ~20% of completed log set data for testing the model. As the result of neural model testing, R2 is score 0.86 with RMS 5% oil saturation. In this testing step, oil saturation log prediction is compared to actual data. Only minor data that shows different oil saturation value and overall shape of oil saturation logs are match. This neural network model is then used for oil saturation log prediction in 19 incomplete log set. The oil saturation log prediction method can fill the gap of data to better describe the depletion process in a new steamflood area. This method also helps to align steam map and remaining oil to support reservoir management in a steamflood project.
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Dutta, Shaktim, Kamaljeet Singh, Gaurav Agrawal, and Apoorva Kumar. "Unlocking the Potential of Fiber-Optic Distributed Temperature Sensing in Resolving Well Integrity Issues." In Offshore Technology Conference. OTC, 2021. http://dx.doi.org/10.4043/30990-ms.
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Abstract Multiple leaks in production tubing of deep wells can be efficiently identified using fiber-optic distributed temperature measurement and thereby mitigating the health, safety and environment (HSE) risk associated with a potential well barrier failure. Further, a production log can be used to gain more insight and finalize a way ahead to resolve the issues of the well integrity. An innovative solution-driven approach was identified with fiber-optic distributed measurement playing a key role. Multiple leaks were suspected in the production system and a fiber-optic cable was run to identify possible areas of leak path. In these deep wells, after the fiber-optic data acquisition, a production log was recorded across selective depths to provide more insights on leak paths. Post identification of leak depths, a definitive decision between tubular patching and production system overhaul was decided based on combined outputs of fiber-optic, production log and tubular patch technology. Results are presented for a two-well operation. Taking an example of Well A, leaks were successfully identified at three depths using the novel operational approach. Further, operation time was reduced from three days (conventional production log measurement performed during daylight operation) to one day (combination of fiber-optic distributed temperature sensing and production log in a single run). Diagnosis of production system issues were completed in one flowing and one shut-in survey condition, thereby reducing the risk of HSE exposure with multiple flowing conditions (conventional production log measurement). Additional insight and confirmation on leaks were observed from production log data which helped identify the presence of a leak across the tubing body. This observation was substantial in deciding whether to proceed with tubing patch or replace the entire production tubing. Tubing patch technology was not satisfactorily recognized to provide well integrity across leak depths. Hence, the decision was made to replace the entire production tubing. The novel operational approach affirms the versatility of fiber-optic distributed temperature measurement in solving critical issues of operation time and reducing HSE exposure while delivering decisive information on production system issues. The paper serves as a staging area for other applications of similar nature to unlock even wider horizons for distributed temperature sensing.
Reports on the topic "Temperature log"
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Zyvoloski, George A. Post Experiment 2062 Temperature Log. Office of Scientific and Technical Information (OSTI), July 1985. http://dx.doi.org/10.2172/1321633.
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Brown, Donald W. Post Expt. 2074 Temperature Log in EE-2A. Office of Scientific and Technical Information (OSTI), January 1988. http://dx.doi.org/10.2172/1244368.
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Kelkar, Sharad. EE-3A Temperature and Caliper Log, Experiment 2060. Office of Scientific and Technical Information (OSTI), June 1985. http://dx.doi.org/10.2172/1321616.
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Zyvoloski, George A. Experiment 2062: The Post Experiment 2061 Temperature Log. Office of Scientific and Technical Information (OSTI), July 1985. http://dx.doi.org/10.2172/1321646.
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Zyvoloski, George A. Post Experiment 2059 Temperature Log in EE-3A – May 29, 1985. Office of Scientific and Technical Information (OSTI), May 1985. http://dx.doi.org/10.2172/1321629.
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Dreesen, Donald S., and David W. Anderson. Logging Report 1 – Temperature/Gamma Ray/Collar Locator Log, EE-2A, 2450 psig Shut-in Log, August 8, 1991. Office of Scientific and Technical Information (OSTI), August 1991. http://dx.doi.org/10.2172/1248142.
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Wielens, H., and C. Jauer. Overpressure, thermal maturity, temperature and log responses in basins of the Grand Banks of Newfoundland. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2001. http://dx.doi.org/10.4095/212235.
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Samach, Alon, Douglas Cook, and Jaime Kigel. Molecular mechanisms of plant reproductive adaptation to aridity gradients. United States Department of Agriculture, January 2008. http://dx.doi.org/10.32747/2008.7696513.bard.
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Annual plants have developed a range of different mechanisms to avoid flowering (exposure of reproductive organs to the environment) under adverse environmental conditions. Seasonal environmental events such as gradual changes in day length and temperature affect the timing of transition to flowering in many annual and perennial plants. Research in Arabidopsis and additional species suggest that some environmental signals converge on transcriptional regulation of common floral integrators such as FLOWERING LOCUS T (FT). Here we studied environmental induction of flowering in the model legume Medicago truncatula. Similarly to Arabidopsis, the transition to flowering in M. truncatula is hastened by long photoperiods and long periods of vernalization (4°C for 2-3 weeks). Ecotypes collected in Israel retain a vernalization response even though winter temperatures are way above 4°C. Here we show that this species is also highly responsive (flowers earlier) to mild ambient temperatures up to 19°C simulating winter conditions in its natural habitat. Physiological experiments allowed us to time the transition to flowering due to low temperatures, and to compare it to vernalization. We have made use of natural variation, and induced mutants to identify key genes involved in this process, and we provide here data suggesting that an FT gene in M.truncatula is transcriptionally regulated by different environmental cues. Flowering time was found to be correlated with MtFTA and MtFTB expression levels. Mutation in the MtFTA gene showed a late flowering phenotype, while over-expressing MtFTA in Arabidopsis complemented the ft- phenotype. We found that combination of 4°C and 12°C resulted in a synergistic increase in MtFTB expression, while combining 4°C and long photoperiods caused a synergistic increase in MtFTA expression. These results suggest that the two vernalization temperatures work through distinct mechanisms. The early flowering kalil mutant expressed higher levels of MtFTA and not MtFTB suggesting that the KALIL protein represses MtFTA specifically. The desert ecotype Sde Boker flowers earlier in response to short treatments of 8-12oc vernalization and expresses higher levels of MtFTA. This suggests a possible mechanism this desert ecotype developed to flower as fast as possible and finish its growth cycle before the dry period. MtFTA and FT expression are induced by common environmental cues in each species, and expression is repressed under short days. Replacing FT with the MtFTA gene (including regulatory elements) caused high MtFTA expression and early flowering under short days suggesting that the mechanism used to repress flowering under short days has diversified between the two species.The circadian regulated gene, GIGANTEA (GI) encodes a unique protein in Arabidopsis that is involved in flowering mechanism. In this research we characterized how the expression of the M.truncatula GI ortholog is regulated by light and temperature in comparison to its regulation in Arabidopsis. In Arabidopsis GI was found to be involved in temperature compensation to the clock. In addition, GI was found to be involved in mediating the effect of temperature on flowering time. We tested the influence of cold temperature on the MtGI gene in M.truncatula and found correlation between MtGI levels and extended periods of 12°C treatment. MtGI elevation that was found mostly after plants were removed from the cold influence preceded the induction of MtFT expression. This data suggests that MtGI might be involved in 12°C cold perception with respect to flowering in M.truncatula. GI seems to integrate diverse environmental inputs and translates them to the proper physiological and developmental outputs, acting through several different pathways. These research enabled to correlate between temperature and circadian clock in M.truncatula and achieved a better understanding of the flowering mechanism of this species.
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McDannell, K. T., N. Pinet, and D. R. Issler. Exhuming the Canadian Shield: preliminary interpretations from low-temperature thermochronology and significance for the sedimentary succession of the Hudson Bay Basin. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/326100.
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The geological history of the Canadian Shield is difficult to constrain because the sedimentary record is missing in those areas where Precambrian basement is exposed at the surface. This study presents preliminary results and interpretations of new apatite fission-track (AFT) analyses to elucidate the low-temperature (&lt;120°C) history across Canada. The AFT modelling of samples from Southampton Island, in Nunavut, indicates that maximum temperatures varied between 62°C and 93°C during the Phanerozoic. Maximum burial occurred in the Devonian, but a second phase of Mesozoic burial is proposed, especially in the case for the sample recovered closest to the northern island-bounding normal faults. The AFT modelling of a sample from northern Ontario indicates that a maximum burial temperature of approximately 75°C was reached during the Late Devonian. Overall, these results demonstrate that the Hudson Bay sedimentary succession is the remnant of a more extensive and thicker sedimentary cover than is preserved. This study also provides the opportunity to discuss innovative methodology and modelling approaches for low-temperature thermochronology.
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Akto, P., Z. Chen, and K. Hu. Evaluation of geothermal resource potential of hot sedimentary aquifers in the Horn River Basin, northeast British Columbia, Canada. Natural Resources Canada/CMSS/Information Management, 2023. http://dx.doi.org/10.4095/331225.
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This study assesses the geothermal potential of Hot Sedimentary Aquifers underlying the Horn River Basin (HRB) based on analyses of borehole temperatures, geological and production data, core porosity and permeability measurements, and geophysical well logs. The proposed criteria are applied to evaluate the geothermal potential of the Horn River Group (HRG) and sub-HRG formations. Favourable spots are identified and ranked by applying temperature, thickness, porosity, permeability and flow rate mapping. The results show that the HRG and its underlying strata have a good potential of geothermal energy resource. Among the HRG formations with an average temperature of 110°C, the Otter Park Formation is the hottest and relatively thick with high water production rate. The Muskwa Formation is the second favourable for geothermal resource potential. Within the sub-HRGs, the Slave Point Formation is the most advantageous because of the high flow rate and high temperature, while the Keg River Formation is the hottest and thickest, and is considered as the second favorable stratigraphic unit. Combining the geological and geographical characteristics, four favourable hot zones have been identified, further indicating that the northwest Zone 1 and the southeast Zone 4 are the hottest areas with thicker reservoirs (&gt;300m) and higher temperatures &gt;130°C (at depth &gt;3 km).