Gotowe bibliografie tematyczne / CHEMICAL TECHNIQUE

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Gotowa bibliografia na temat „CHEMICAL TECHNIQUE”

Autor: Grafiati

Data publikacji: 11 września 2023

Data aktualizacji: 16 kwietnia 2024

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Artykuły w czasopismach na temat "CHEMICAL TECHNIQUE"

B. A. Ezekoye, B. A. Ezekoye, P. O. Offor P.O. Offor, V. A. Ezekoye V. A. Ezekoye i F. I. Ezema F. I. Ezema. "Chemical Bath Deposition Technique of Thin Films: A Review". International Journal of Scientific Research 2, nr 8 (1.06.2012): 452–56. http://dx.doi.org/10.15373/22778179/aug2013/149.

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Kamarun, Dzaraini, Khadijah Omar i Farida Zuraina Yusof. "Chemical and Thermal Analysis of Silk and Silk-Like Fibres". Advanced Materials Research 1134 (grudzień 2015): 123–26. http://dx.doi.org/10.4028/www.scientific.net/amr.1134.123.

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Natural silk and silk-like synthetic fibres share common external features and ‘hand’ characteristics which cause confusion to end users. Standard chemical tests are the best known technique available but not the most desirable due to the use of chemicals. An alternative technique, thermogravimmetric analysis using a thermogravimmetric analyzer (TGA) is as reliable and is more environmental-friendly. Several fabric samples of natural (silk) and synthetic origin were tested for comparison using the two techniques: TGA and a standard chemical procedure. Bivoltaine and multivoltaine cocoons were used as standards. It was found that all fabric samples tested using TGA agreed with the results obtained from chemical analysis implying the potential of using TGA as an alternative technique to the wet chemical method.

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Guan, Yuduo, Bin Ai, Zengyao Wang, Chong Chen, Wei Zhang, Yu Wang i Gang Zhang. "In Situ Chemical Patterning Technique". Advanced Functional Materials 32, nr 2 (7.10.2021): 2107945. http://dx.doi.org/10.1002/adfm.202107945.

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Chaudhari, Manisha, i Krunal Solanki. "Role of Crisper-Cas Technique in Bioremediation of Pesticides". International Journal of Current Microbiology and Applied Sciences 12, nr 8 (10.08.2023): 82–93. http://dx.doi.org/10.20546/ijcmas.2023.1208.010.

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Pesticides, insecticides, certain pharmaceuticals, chemically dangerous chemicals which can pollute the environment. Pesticides are primarily used to manage plants, flies, parasitic fungus, and parasites in crop fields. The desire to limit pesticide effects on soil and offsite environments has encouraged research interest in pesticide and related chemical biodegradation. As a result, quick and safe agents for environmental bioremediation, individual decontamination, and therapeutic detoxication are urgently needed. Bioremediation is environment friendly so if we use such kind of technique then more helpful. The ability of microorganisms to degrade complex chemical substances in the environment is referred to as bioremediation. The discovery of CRISPR, mechanism of the CRISPR-based nuclear adaptive immune system "CRISPR associated system, Cas", and its diversion to powerful tools for gene editing revolutionize the field of molecular biology. Brought about and stimulated new and improved gene therapy. By using CRISPR technique transfer desired gene and decrease toxic elements.

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Parulekar, Prasad J. "Chemical Plant Utility – Nitrogen System Design". International Journal for Research in Applied Science and Engineering Technology 9, nr 11 (30.11.2021): 1560–67. http://dx.doi.org/10.22214/ijraset.2021.39047.

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Abstract: The study is been conducted to understand the different techniques to separate nitrogen from atmospheric air. Separation of nitrogen takes place by following techniques: Cryogenic air separation, Pressure swing adsorption and Membrane separation technique. Cryogenic air separation operates at a very low temperature, which uses the principle of rectification to separate nitrogen at a very high purity (99.999%). Pressure swing adsorption rely on the fact that higher the pressure, more the gas is adsorbed which results in high purity (95-99.99%) of nitrogen. Membrane separation technology is the process that uses hollow fibre membranes to separate the constituent gases in air, which gives the purity in the range of 93%-99.5%. After the comparative study, it is understood that membrane separation technique is the most efficient technology based on the cost, purity, flexibility in terms of adjusting the purity, maintenance, availability; it operates without heating and therefore uses less energy than conventional thermal separation processes. Different step designs of membrane separation techniques are discussed. A Process Flow Diagram and Piping Instrumentation Diagram is been added for single step membrane separation technique. Keywords: Atmospheric air, nitrogen, Cryogenic air separation, Pressure swing adsorption, Membrane separation technique.

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Cherney, Daniel P. "Chemical Mapping of Rubbers and Polymers via Confocal Raman Spectroscopic Imaging". Rubber Chemistry and Technology 82, nr 4 (1.09.2009): 418–29. http://dx.doi.org/10.5254/1.3548255.

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Abstract Confocal Raman Spectroscopic Imaging has been demonstrated as a non-destructive technique to determine the spatial and chemical content of rubbers and polymers. Raman spectroscopy is a particularly useful tool for characterizing chemicals and mixtures because each chemically-distinct species has a unique Raman spectrum. The addition of confocal optics to the microscope greatly improves both the lateral and axial spatial resolution of the instrument. The lateral resolution of the instrument is less than one-third of a micron. The axial resolution, the resolution in the direction of incident light propagation, is as good as two microns with an air objective and on the order of a micron for an oil immersion objective. The vast enhancement of resolution provided by the confocal optical arrangement allows rubber and polymer mixtures to be mapped in multiple dimensions with excellent spatial, chemical, and morphological specificity. Confocal Raman microscopy is a rapid technique that should be considered as an alternative, or in addition, to analysis that requires other microscopic techniques such as atomic force microscopy (AFM) or scanning electron microscopy (SEM).

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Chia, Victor. "A Review of Analytical Techniques for Identifying Contaminants in the Semiconductor Industry". Journal of the IEST 45, nr 1 (14.09.2002): 37–44. http://dx.doi.org/10.17764/jiet.45.1.f686p346016054p1.

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The appropriate analytical technique to characterize contamination requires the correct measurement instrument, together with careful experimental design and data analysis to eliminate random and systematic errors. When selecting the analytical technique for a specific application, it is important to recognize the advantages and limitations of the technique. This paper reviews common analytical techniques to monitor the purity of cleaning chemicals, solvents, and water; cleanroom environment and components; wafer boxes; and wafers. The techniques described are wet chemical analytical methods and microanalytical methods.

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Ganguly, Sutapa, Sukhen Das i Sujata G. Dastidar. "A study on structural ,morphological and chemical composition of zinc sulphide nanoparticles synthesized by a simple chemical technique". International Journal of Scientific Research 2, nr 7 (1.06.2012): 472–73. http://dx.doi.org/10.15373/22778179/july2013/161.

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Pan, Yanhong, Liang Hu i Tao Zhao. "Applications of chemical imaging techniques in paleontology". National Science Review 6, nr 5 (10.10.2018): 1040–53. http://dx.doi.org/10.1093/nsr/nwy107.

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AbstractChemical imaging techniques, based on a combination of microscopy and spectroscopy, are designed to analyse the composition and spatial distribution of heterogeneous chemical complexes within a sample. Over the last few decades, it has become an increasingly popular tool for characterizing trace elements, isotopic information and organic biomarkers (molecular biosignatures) found in fossils. Here, we introduce the analytical principle of each technique and the interpretation of the chemical signals, followed by a review of the main applications of these techniques in paleontology. We also demonstrate that each technique is associated with pros and cons, and the current limitations and obstacles associated with the use of each specific technique should be taken into account before being applied to fossil samples. Finally, we propose that, due to the rapid advances in the available technology and overall trends towards more multi-disciplinary studies in paleontology, chemical imaging techniques can be expected to have broader applications in paleontology in the near future.

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Kodikara, J. K., F. Rahman i S. L. Barbour. "Towards a more rational approach to chemical compatibility testing of clay". Canadian Geotechnical Journal 39, nr 3 (1.06.2002): 597–607. http://dx.doi.org/10.1139/t02-003.

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Chemical compatibility tests using hydraulic conductivity testing with chemical permeants are normally undertaken to assess the integrity of compacted clayey liners used for waste containment. This paper highlights the fact that current routine methods of flexible wall and rigid wall testing techniques fail to represent the zero lateral strain boundary condition that is required to realistically represent the field situation. The test results indicate that flexible wall permeameters underestimate the likely increases in hydraulic conductivity due to chemicals, while the rigid wall permeameters can severely overestimate these effects. A new test technique, which incorporates the zero lateral strain condition in a simple manner, is presented. This technique involves the use of a rigid wall concept in a flexible wall permeameter. A split rigid mould is used to encase the soil specimen that is glued to the internal surfaces of the mould, to apply the zero lateral strain boundary condition. The new technique is shown to be suitable for both chemical compatibility and desiccation testing. The tests were undertaken with varying concentrations of saline water, methanol, and landfill leachate. The test results indicate that the new technique produces results that fall between the results obtained from flexible wall and rigid wall permeameters. It is argued that the new test technique provides a more rational approach for chemical compatibility testing than the current rigid wall and flexible wall techniques.Key words: soil, hydraulic conductivity, chemical compatibility, landfill, permeameter, boundary condition.

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Rozprawy doktorskie na temat "CHEMICAL TECHNIQUE"

Wang, Chuangnan. "Ultrasonic technique for chemical process control". Thesis, University of Strathclyde, 2014. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24442.

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Ultrasound has found application in chemical processing control using both low power, high frequency monitoring techniques and high power, low frequency process enhancement approaches. In many cases, standard ultrasonic systems are retrofitted to a process and while these produce efficiency improvements, the design of bespoke systems may offer more potential. In particular, this Thesis has considered two techniques used in the biomedical field; harmonic imaging and high intensity focused ultrasound (HIFU) and has translated these into ultrasonic transducers for use in an industrial process control system. Traditional ultrasound monitoring techniques are based on operation in the linear domain and are used to monitor chemical processes by measurement of material acoustic velocity, attenuation or based on spectral analysis. Both active and passive methods have been reported for application in this industrial sector. One issue is the presence of multiple reflections in the received ultrasonic signal which can mask the signals of interest from the load medium. This Thesis has considered a new ultrasonic monitoring approach using a combination of both linear and nonlinear spectral components. This was applied to high-throughput products and a dual frequency transducer designed and fabricated to acquire the ultrasonic backscattered signals in both the fundamental and second harmonic frequency regimes. The additional information provided by the harmonic device enabled discrimination between shampoo and conditioner products with the same density, but different molecular weights. HIFU transducer array designs are then considered for high power, low frequency chemical process enhancement applications. Typical applications of high power ultrasound use single or multiple discrete transducers to insonify a process. These are effective, but inflexible in the delivery of the ultrasonic field. The application of a HIFU array would provide control of the high power focal region in the load medium, which offer advantages to industry. Two transducer array approaches have been considered in this Thesis based on piezoelectric composite configurations. Three HIFU arrays based on the 1-3 piezocomposite have been fabricated to operate between 200-400kHz and fully characterised to evaluate their high power performance. A second transducer configuration was based on a novel 2-2 piezocomposite with a 2 layer stacked configuration. Simulation of this transducer design illustrated its potential for high power applications, although a number of fabrication issues resulted in the manufactured array not operating at full capacity. Importantly, the transducer configurations developed in this Thesis are shown to induce cavitation through the standard aluminium foil test.

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Loehn, Clayton William. "Investigation of the monazite chemical dating technique". Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/27688.

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In order to evaluate the electron microprobe (EMP) method for chemical dating of monazite, we chemically analyzed selected suites of monazite grains that were previously dated by standard U/Pb isotopic methods at three laboratories each equipped with a sensitive high resolution ion microprobe (SHRIMP). Representing diverse igneous and metamorphic lithologies, these grains yielded conventional isotopic ages ranging in age from Neoarchean to Devonian. Chemical dating was performed at Virginia Tech using a Cameca SX-50 EMP in which the analytical routines and settings were specifically optimized for monazite geochronology, including correction of analytical peaks for all major spectral interferences and correction of peak intensities for local background emission. Placement of cross-grain analytical traverses was based on backscattered electron (BSE) images together with wavelength-dispersive (WD) generated X-ray maps for Y, Th, U, and Ca, which revealed the internal compositional complexity of each grain. Shorter EMP traverses were selected adjacent to each SHRIMP pit in order to provide the best possible comparison of ages obtained by the two dating methods. Synthesis protocol for key elemental measurements (Y, Th, U, and Pb) was developed utilizing the 1Ï elemental errors associated with individual analyses, providing an objective approach for data synthesis. Analytical dates were either accepted or excluded based on analytical and spatial justifications. Isotopic dating techniques utilize three independent age calculations, provided the sample is old enough to have accumulated sufficient 207Pb (i.e., â ¥~1000 Ma). Similarly, the chemical dating method can utilize two independent age calculations (i.e., Th/Pb and U/Pb) and a U-Th-Pbtotal centroid age in Th/Pb vs. U/Pb space, verified independently against the calculated Th* or U* CHIME ages. Across the entire 2,200 m.y. age range represented by the sample set, the chemical ages calculated from the EMP data chemical ages are internally consistent (within 2Ï error) with the previously measured SHRIMP isotopic ages, except in one case where bulk mixing of discrete age domains within an ablation pit led to an isotopically discordant apparent age. Overall, this study illustrates that EMP chemical dating (1) represents both an accurate and precise primary method for dating monazite from igneous and polymetamorphic terrains; (2) provides superior spatial resolution for obtaining meaningful ages from small and/or irregular domains of discrete age that may be irresolvable or misinterpreted by other dating techniques that sample larger volumes; and (3) illuminates the geological meaning of isotopically discordant monazite ages obtained using conventional methods with lower spatial resolution (e.g., SHRIMP).
Ph. D.

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Hsu, Ching-Ming. "High resolution SIMS analysis using a chemical bevelling technique". Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243823.

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Zenaitis, Michael G. (Michael Guy). "Antibiotic production using the self-cycling fermentation technique". Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68061.

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The self-cycling fermentation (SCF) technique was used to grow three species of the genus Streptomyces which have been described as producing antibiotics. Application of this technique led to reproducible growth patterns for filamentous organisms. Control of the system using the CO$ sb2$ concentration in the off-gas was achieved under conditions which prevented monitoring of the dissolved oxygen. It was also possible to use the SCF system with either defined or complex media.
Production of tetracycline by S. aureofaciens was obtained on an iron-deficient medium. The production rate was as high as 0.272 g tetracycline/g sucrose/h. This was comparable with that reported for tetracycline in the patent literature. Growth patterns of the SCF when tetracycline was present in the fermenter were erratic, demonstrating the negative effect of the antibiotic on the growth of the producer organism. Further growth in a secondary fermenter system resulted in additional production over a period of about fifteen hours. In these experiments, tetracycline exhibited characteristics of a siderophore.

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Wentworth, Stephen. "Citric acid production using the self-cycling fermentation technique". Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68057.

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Self-cycling fermentation is a new technique used to cultivate synchronous populations of cells. This work used the technique in the production of citric acid from a strain of Candida lipolytica. Application of this technique resulted in extremely stable, reproducible patterns of growth and induced a high level of cell synchrony. Synchrony was maintained even throughout long periods of extended nutrient starvation. Thus, self-cycling fermentations can be operated with cycle times significantly longer than the doubling time of the microorganism. Use of this technique led to a full order of magnitude increase in the specific biomass production rate compared to literature values. This biomass was found to be suitable for the production of citric acid in a second stage reactor. Although this preliminary work with the second stage reactor was not optimized, the specific citric acid production rate obtained was comparable to rates found in the literature.

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Truter, Lara. "Development of a zeolite washcoating technique for microchannel reactors". Master's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/10855.

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Microreactor technology is becoming an increasingly active research field in terms of chemical reaction engineering and process intensification. An important feature of microreactor technology is the requirement of a catalyst layer.

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Vadhwana, V. A. "A model simplification technique for computer flowsheeting". Thesis, London South Bank University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382822.

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Arayarat, Pornthip. "Refractory products based on the pore reduced cement technique". Thesis, University of Aberdeen, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245256.

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The present study was aimed at an investigation of the use of the pore reduced cement (PRC) technique on the fabrication and properties of calcium aluminate-based refractories. Physical and chemical performances were compared with those of conventionally prepared (unpressed) refractory castables. The influence of firing on two types of calcium aluminate cements; (Ciment Fondu and Secar 80), mixed with aggregates such as firebrick and alpha-alumina, were observed. Most of the pressed samples based on Ciment Fondu cracked and melted during firing to 1250^oC. Pressed samples based on Secar 80, however, tended to crack less with increased tabular alumina content. An appropriate weight proportion of tabular alumina and Secar 80 was found to be 70 to 30. The physical properties of Secar 80 blended with (i) tabular aluminas (20-μm and 250-μm) only and (ii) round (RMA325) and 250-μm tabular alumina were investigated before and after firing to 1350^oC. Pressed tabular alumina mixes containing various percentages of aggregate showed very little change in bulk density (3000 kg/m³) and flexural strength (23 MPa), but after firing, flexural strengths increased considerably as the fine tabular alumina content increased (up to 50 MPa). Microstructural evidence indicated that the interlocking structure occurring from the crystallisation of hexagonal plates of calcium hexaluminate including partial sintering of fine alumina grains could be the origin of the increased strength on firing. Although unpressed samples show similar structures, they are more porous. On firing, unpressed samples tended to expand (0.43 to 0.64%) less than pressed samples (1.32 to 1.71%) because the phase transformation from CA₂ to CA₆occurred which in pressed samples leads to expansion whereas in unpressed products, expansion is accommodated within available porosity. Abrasion resistance increases as strength increases. Fracture toughness increases with the coarse tabular alumina content increases. Similar improvements in bulk density and flexural strength are observed when round alumina (~ 44μm) and tabular alumina (250-μm) are blended. The thermal shock resistance of pressed samples was also found to be better than for unpressed samples as shown by the higher relative strength after the test. The chemical durability of unpressed and pressed samples based on the slag test was investigated. Pressed samples resist slag penetration better than the unpressed samples because of the smaller pores and reduced pores connectivity. Otherwise, chemical interaction between cement and slag was similar. In conclusion, refractory products based on the PRC technique have shown considerable improvements in both physical and chemical performance, especially green strengths which are substantially higher than for conventional castables, making them less susceptible to handling damage prior to service, i.e. during transport and installation.

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Wener, Evan. "The biomechanics of ascending aortic aneurysms: The effect of measurement technique". Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=117062.

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An ascending aortic aneurysm is a pathologic enlargement of the ascending portion of the aorta. Comorbidities of dilation include aortic valve disease and connective tissue disorders. If the ascending aorta exceeds a threshold diameter, open heart surgery is recommended. This is a traumatic procedure and the recovery is demanding. As our population ages and with improved technologies to diagnose the disease, the number of cases will increase every year. Understanding the mechanics of ascending aortic tissue will help cardiac surgeons make timely decisions on when to intervene. There are many ways to characterize the mechanical properties of aortic tissue. In this study, we used biaxial and uniaxial tensile testing with an optical tracking system to record the Green-Lagrangian (Green strain) strain. Engineering and true stiffness values were calculated and compared along with patient characteristics. Aortas were classified by valve type as healthy, tricuspid, bicuspid type 1 and bicuspid type 2. The results show that diseased tissue does behave differently than healthy tissue indicating that a local remodeling does occurs to the aortic wall. There are also differences in the mechanics between the types of diseased valves suggesting that valve type also affects the way the aortic wall responds to the disturbed hemodynamic environment. Correlations between stiffness and patient characteristics show that no matter which experimented technique or method of stiffness calculation is used, relationships are generally conserved. The only difference is the magnitude of the elastic modulus. The conclusions drawn from the data would not change whether biaxial or uniaxial experiments were performed. However when comparing engineering and true stiffness, only 7/12 covariances were similar and therefore the conclusions are inconsistent.
Un anévrisme de l'aorte ascendante est un agrandissement pathologique de l'aorte ascendante. Les comorbidités de dilatation incluent les maladies de la valve aortique et du tissu conjonctif. Si l'aorte ascendante dépasse un diamètre seuil, la chirurgie à cœur ouvert est recommandée. Il s'agit d'une procédure traumatique et la récupération est exigeante. Comme notre population vieillit et que les technologies pour diagnostiquer la maladie se sont beaucoup améliorées, le nombre de cas décelé va augmenter chaque année. Comprendre les mécanismes du tissu aortique ascendant aidera les chirurgiens cardiaques à prendre les bonnes décisions au bon moment. Il y a plusieurs façons de caractériser les propriétés mécaniques du tissu aortique. Dans cette étude, nous avons utilisé les essais de traction biaxiale et uniaxiale avec un système de suivi optique pour enregistrer la souche Green-Lagrange (souche verte). Valeurs de rigidité d'ingénierie et de vrai ont été calculées et comparées avec les caractéristiques des patients. Les aortes ont été classées en 4 types de valves : bonne santé, tricuspides, bicuspides de type 1 et bicuspides de type 2. Les résultats montrent que les tissus malades sont différents des tissus en bonne santé qui indiquent qu'un remodelage local se produit sur la paroi aortique. Il existe aussi des différences dans le mécanisme des différents types de valvules qui suggèrent que le type de valve affecte également la façon dont la paroi aortique répond à l'environnement perturbé hémodynamique. Les corrélations entre les caractéristiques de rigidité et le patient nous montrent que quelque-soit la technique ou la méthode de calcul utilisée pour la rigidité, les relations sont généralement conservées. La seule différence est la grandeur du module d'élasticité. Les conclusions tirées de ces données ne changeraient pas, peu importe le type d'expérimentation effectué; biaxiale ou uniaxiale. Cependant, lorsque l'on compare la rigidité d'ingénierie et de vrai, seulement 7 covariances sur 12 sont similaires et les conclusions sont contradictoires.

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Tontiwachwuthikul, Paitoon. "New pilot plant technique for designing gas absorbers with chemical reactions". Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/32182.

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Gas absorption with chemical reaction is an important unit operation in the chemical and petroleum industries for the selective removal of components from industrial gas streams. Apart from choosing absorption media, the most difficult problems facing the design engineer are the sizing and performance prediction of the absorption tower due to the scarcity of fundamental design data, especially when novel absorption media and/or packings are used. The solubility of carbon dioxide in 2 and 3 M solutions of 2-amino-2-methyl-1-propanol (AMP), which is a newly introduced absorbent, was determined at 20, 40, 60 and 80 °C and for CO₂ partial pressures ranging from approximately 1 to 100 kPa. The results were interpreted with a modified Kent-Eisenberg model which predicted the present and previous experimental results well. The absorption capacities of AMP and monoethanolamine (MEA) solutions were also compared. Detailed concentration and temperature measurements were reported for the absorption of carbon dioxide from air into NaOH, MEA and AMP solutions. A full-length absorber (0.1 m ID, packed with 12.7 mm Berl Saddles up to heights of 6.55 m) was used. It was operated in countercurrent mode and at 30 to 75 % flooding velocities which are typical for gas absorber operations. The following ranges of operating conditions were employed: superficial gas flow rate 11.1 to 14.8 mol/m² s; superficial liquid flow rate 9.5 to 13.5 m³/m² h; feed CO₂ concentration 11.5 to 19.8 %; total absorbent concentration 1.2 to 3.8 kmol/m³; liquid feed temperature 14 to 20 °C; total pressure 103 kPa. The measurements for the CO₂-NaOH and CO₂-MEA systems were compared with predictions from a previously developed mathematical model. Generally good agreement was obtained except at high CO₂ loadings of MEA solutions. Compared with MEA, AMP was found to have superior CO₂ absorption capacities and inferior mass transfer rates. A new procedure, called the Pilot Plant Technique (PPT), for designing gas absorbers with chemical reactions has been developed. The PPT is primarily intended for designing absorbers for which fundamental design information is lacking. It is based on the premise that full-length absorption columns can be sized by making a minimum number of tests using a small-scale pilot plant. Two special features of the PPT are (i) the details of hydrodynamic parameters (i.e. mass transfer coefficients, effective interfacial area and liquid hold-up) and the physico-chemical information of the system (e.g. reaction mechanism, reaction rate constants) need not be known and (ii) complex calculations are avoided. Using the PPT to size the height or to predict the performance of a given full-length absorber, the specific absorption rate, which is the essential information, can be measured directly using the pilot plant model (PPM) column if both columns have the same hydrodynamic conditions. This can be achieved by using the same type and size of packing in the PPM and the full-length columns and ensuring that the end and wall effects are negligible. The PPM column must also be operated at the same superficial fluid velocities as those of the full-length column. The specific absorption rate was then obtained from the gradient of the fluid composition profile along the PPM column. The validity of the PPT was demonstrated by determining the height and predicting the performance of the full-length column in which carbon dioxide was absorbed from air by aqueous solutions of NaOH and AMP at various operating conditions; good agreement was obtained.
Applied Science, Faculty of
Chemical and Biological Engineering, Department of
Graduate

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Książki na temat "CHEMICAL TECHNIQUE"

Royal Society of Chemistry (Great Britain), red. More modern chemical techniques. London: Royal Society of Chemistry, 2001.

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The laboratory handbook of materials, equipment, and technique. Englewood Cliffs, N.J: Prentice Hall, 1992.

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H, Hablanian M., red. Vacuum technique. London: Taylor & Francis, 2002.

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S, Coyne Gary, red. The laboratory companion: A practical guide to materials, equipment, and technique. Hoboken, NJ: Wiley-Interscience, 2006.

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Cresser, Malcolm S. Flame spectrometry in environmental chemical analysis: A practical guide. London: Royal Society of Chemistry, 1994.

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S, Coyne Gary, red. The laboratory companion: A practical guide to materials, equipment, and technique. New York: Wiley, 1997.

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Chemical cytometry: Ultrasensitive analysis of single cells. Weinheim: Wiley-VCH, 2010.

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H, Brockmann Uwe, i Warwick Richard Martyn, red. Tidal estuaries: Manual of sampling and analytical procedures. Rotterdam: Published for the European Commission by A.A. Balkema, 1994.

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Allen, C. Clark. Field evaluation of hazardous waste pretreatment as an air pollution control technique. Cincinnati, OH: U.S. Environmental Protection Agency, Hazardous Waste Engineering Research Laboratory, 1986.

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Singh, Prabhat K. Femtosecond fluorescence up-conversion: A time-gated frequency mixing technique for ultrafast chemical dynamics. Mumbai: Bhabha Atomic Research Centre, 2009.

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Części książek na temat "CHEMICAL TECHNIQUE"

Brickmann, J., S. M. Kast, H. Vollhardt i S. Reiling. "Trends in Molecular Dynamics Simulation Technique". W Frontiers of Chemical Dynamics, 217–53. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0345-9_10.

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Cavegn, Brigitta Maria. "Home Peeling: A Combined Technique". W Color Atlas of Chemical Peels, 71–76. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-20270-4_9.

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Thanopulos, Ioannis. "Quantum Dynamics by Partitioning Technique". W Advances in Chemical Physics Volume 159, 349–94. Hoboken, NJ, USA: John Wiley & Sons, Inc, 2016. http://dx.doi.org/10.1002/9781119096276.ch9.

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Del Valle, E. M., R. Gutierrez i M. A. Galán. "Bioprocess Scale-up: SMB as a Promising Technique for Industrial Separations Using IMAC". W Chemical Engineering, 85–102. Chichester, UK: John Wiley & Sons, Ltd, 2005. http://dx.doi.org/10.1002/0470025018.ch4.

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Hopkins, John B., i P. M. Rentzepis. "Picosecond Transient Raman Studies: Technique and Applications". W Advances in Chemical Reaction Dynamics, 151–63. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4734-4_9.

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Spanhoff, R., i J. M. Suijlen. "Chemical Tracers — A New and Desirable Technique?" W Estuarine Water Quality Management, 235–38. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-75413-5_35.

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Spanhoff, R., i J. M. Suijlen. "Chemical tracers—A new and desirable technique?" W Estuarine Water Quality Management Monitoring, Modelling and Research, 235–38. Washington, D. C.: American Geophysical Union, 1990. http://dx.doi.org/10.1029/ce036p0235.

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Marturano, Matthew N., Sullivan A. Ayuso i B. Todd Heniford. "Chemical Component Separation Technique in Hernia Repair". W Newer Concepts and Procedures in Hernia Surgery - An Atlas, 209–18. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5248-7_22.

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Shigemasa, Eiji, i Nobuhiro Kosugi. "Molecular Inner-Shell Spectroscopy. ARPIS Technique and its Applications". W Advances in Chemical Physics, 75–126. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2011. http://dx.doi.org/10.1002/9781118135242.ch2.

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Majozi, Thokozani. "A Graphical Technique for Wastewater Minimisation in Batch Processes". W Batch Chemical Process Integration, 247–73. Dordrecht: Springer Netherlands, 2009. http://dx.doi.org/10.1007/978-90-481-2588-3_12.

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Streszczenia konferencji na temat "CHEMICAL TECHNIQUE"

Oldenborg, Richard C., Steven L. Baughcum i Douglas E. Hof. "Photofragment Fluorescence as an Analytical Technique for Gas-Phase Alkali Compounds". W Laser Applications to Chemical Analysis. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/laca.1987.mb3.

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Sensitive techniques are needed for the detection of highly corrosive gas-phase alkali compounds in the combustion of coal gas to drive gas turbines. It has been suggested1 that photofragment fluorescence, i.e., the observation of electronically excited photofragments from the photodissociation of the parent compound at suitably short ultraviolet wavelengths, would be a practical diagnostic technique. A recent investigation2 of the photodissociation of gas-phase sodium and potassium chlorides to produce excited alkali atoms has shown that the photofragment fluorescence technique can measure these compounds at concentrations down to sub-part-per-billion levels and is linear over at least six orders of magnitude. The photodissociation of other gas-phase alkali compounds has not been previously investigated.

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Co Muñoz, Jose, i Karl Ezra Pilario. "Nonlinear Data Reconciliation and Gross Error Detection using Branch-and-Bound Technique". W Annual International Conference on Chemistry, Chemical Engineering and Chemical Process. Global Science & Technology Forum (GSTF), 2015. http://dx.doi.org/10.5176/2301-3761_ccecp15.15.

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Deka, C., J. A. Stemkamp i Larry A. Sklar. "Fluorescence Lifetime Measurements in a Flow Cytometer by Amplitude Demodulation Using Digital Data Acquisition Technique". W Laser Applications to Chemical Analysis. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/laca.1994.wd.11.

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In this paper we demonstrate, for the first time, fluorescence lifetime measurements by amplitude demodulation from fluorescence signals with time dependent amplitudes in a flow cytometer using digital data acquisition techniques. The lifetime measurements in the flow cytometer have been compared to standard fluorescent lifetime measurements in bulk suspensions. The present technique provides a method for analyzing chemical and biological species based upon their individual excited state lifetime. We also discuss the factors influencing the accuracy of the measurements by this method and the possible solutions to those problems.

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Whitaker, Tom J., Bret D. Cannon i Bruce A. Bushaw. "New Fluorescence Techniques for Detecting Noble Gases(*)". W Laser Applications to Chemical Analysis. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/laca.1987.ma9.

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Two new concepts for detecting noble gases are reported. Both techniques involve formation of the long-lived 1s5 metastable state of noble gases. The first technique utilizes the photon-burst method and should be capable of isotopically selective detection at extremely small relative abundances. The second concept incorporates a shelving technique that stores noble gas atoms in the metastable state and then pumps these atoms to a higher excited state that radiatively cascades to the ground state, emitting vacuum ultraviolet (VUV) photons. A significant advantage is that AlGaAs diode lasers can be used for the techniques rather than continuous wave cw dye lasers.

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Hartshorn, Gary, Benjamin Lanz i Bruce Broussard. "Medium Voltage Cable Predictive Diagnostics Technique". W 2007 IEEE Petroleum and Chemical Industry Technical Conference. IEEE, 2007. http://dx.doi.org/10.1109/pcicon.2007.4365791.

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Prodromakis, T., P. Georgiou, T. G. Constandinou, K. Michelakis i C. Toumazou. "Batch encapsulation technique for CMOS based chemical sensors". W 2008 IEEE Biomedical Circuits and Systems Conference. IEEE, 2008. http://dx.doi.org/10.1109/biocas.2008.4696939.

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Turner, M. "A neural relaxation technique for chemical graph matching". W Fifth International Conference on Artificial Neural Networks. IEE, 1997. http://dx.doi.org/10.1049/cp:19970724.

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Kidder, Linda H., Seth R. Goldstein, Ira W. Levin i E. Neil Lewis. "Raman imaging microscopy: a novel chemical imaging technique". W Electronic Imaging: Science & Technology, redaktorzy Carol J. Cogswell, Gordon S. Kino i Tony Wilson. SPIE, 1996. http://dx.doi.org/10.1117/12.237471.

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Kwon, Yongsung, Seungeun Nam, Hyerim Song, Youin Park, Minyoung Shon, Myungjun Moon, Shivshankar Chaudhari i Samtak Kwag. "Mixed matrix membrane for separation of Acetic acid water mixture by pervaporation technique". W Annual International Conference on Chemistry, Chemical Engineering and Chemical Process ( CCECP 2016 ). Global Science & Technology Forum ( GSTF ), 2016. http://dx.doi.org/10.5176/2301-3761_ccecp16.28.

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Yappert, M. C., C. W. Huie, S. M. Kimbrell i E. S. Yeung. "New Imaging Technique Using Acousto-Optic Deflectors for Mapping of Transient Events". W Laser Applications to Chemical Analysis. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/laca.1987.pdp21.

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The ability to scan acousto-optic deflectors very rapidly (105 -106 Hz), while maintaining spatial resolution makes it possible to obtain frozen one or two dimensional images at different times during the evolution of a single event, such as atomic or molecular populations in a laser generated plume.

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Raporty organizacyjne na temat "CHEMICAL TECHNIQUE"

Hui, Wing C. Technique for protecting chip corners in wet chemical etching of silicon wafers. Office of Scientific and Technical Information (OSTI), luty 1991. http://dx.doi.org/10.2172/10169930.

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Paul Fallgren. Innovative Protocols for in SITU MTBE Degradation by Using Molecular Probes-An Enhanced Chemical-Bio Oxidation Technique. Office of Scientific and Technical Information (OSTI), luty 2009. http://dx.doi.org/10.2172/993521.

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Kropka, Jamie Michael, Mark E. Stavig, Gabe Kenneth Arechederra i John D. McCoy. Predictive Modeling of Polymer Mechanical Behavior Coupled to Chemical Change/ Technique Development for Measuring Polymer Physical Aging. Office of Scientific and Technical Information (OSTI), wrzesień 2017. http://dx.doi.org/10.2172/1397142.

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Solka, Bruce H., i Amir Attari. PR-190-628-R01 Suitable Tracer Gas for Detection of Natural Gas Migration and Leaks. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), maj 1986. http://dx.doi.org/10.55274/r0011938.

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This report presents the results of an extensive literature survey to collect and assemble information on the current state of the tracer technology with the objective of selecting promising techniques that could serve to Positively identify and distinguish the source of leaking and migrating natural gas from other nearby sources of methane or natural gas and not merely indicate the presence of a gas leak. While no single tracer technique was found that would adequately serve this purpose in all situations, however. enough information was collected on potentially useful techniques that merit further study and development. Eighteen different techniques were selected and classified in three broad categories of physical-chemical and nuclear methods. Each cited method was then appraised on the basis of health and safety specificity, economy, ease of application, and status of their commercial development. Of the 18 cited tracer methods, five were recommended for further study and near term application to the gas industry problems.

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Tong, Andrew, Dikai Xu i Liang-Shih Fan. Biomass Gasification for Chemicals Production Using Chemical Looping Techniques. Office of Scientific and Technical Information (OSTI), wrzesień 2023. http://dx.doi.org/10.2172/1997485.

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Brichart, Thomas, Mahmoud Ould Metidji, Mario Silva, Sissel Opsahl Viig i Tor Bjørnstad. Lanthanide-Complexed Esters for Single-Well SOR Measurements. University of Stavanger, listopad 2021. http://dx.doi.org/10.31265/usps.208.

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The main objective has been to improve the prevailing single-well chemical tracer push-and-pull technique, SWCTT, for measurement of residual oil saturation (SOR) in defined pay zones in a single well test [1,2,3] after water injection on the following subjects: • Improvement in tracer detection limits by a factor > 1000 • On-site or even on-line detection of tracer signal in true time • Reduction in the needed amount of tracer by a factor of > 1000 • Reduced footprint on production platforms during tracer operation The intended audience and technology users are oil and service companies.

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Watts, Benjamin E., Danielle E. Kennedy, Ethan W. Thomas, Andrew P. Bernier i Jared I. Oren. Long-Term Durability of Cold Weather Concrete : Phase II. Engineer Research and Development Center (U.S.), styczeń 2021. http://dx.doi.org/10.21079/11681/39579.

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Recent laboratory results confirm that it is possible to protect concrete from freezing solely using chemical admixtures and indicate that the amount of admixture required may be significantly less than previously recommended. Researchers have also verified that admixture-based freeze protection can produce concrete that is durable to winter exposure for a minimum of 20 years, through petrographic examination of core specimens obtained from past field demonstrations. Freeze protection for concrete using chemical admixtures alone has been an area of active research for 3 decades; however, the most recent methodology recommends very high addition rates of accelerating and corrosion inhibiting admixtures, which result in significant challenges, including slump loss, rapid setting, and potentially excessive temperature rise. As part of a laboratory study, researchers systematically varied the dosage of freeze protection admixtures used in concrete cured in a 23 °F environment. Preliminary findings indicate that a 50% reduction in admixture dose maintained adequate freeze protection and resulted in compressive strengths exceeding those of room-temperature controls at 7 and 28 days. The combination of improved handling, reduced cost, and verified durability associated with the use of admixtures for freeze protection makes a compelling case for broader adoption of this technique in winter operations

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Libray, Spring. The Booming Field of Epitranscriptomics and its Role in Human Disease. Spring Library, kwiecień 2021. http://dx.doi.org/10.47496/sl.blog.26.

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Currently, the detection techniques used for transcriptome-wide identification of chemical modifications mainly depend on chemical and antibody-based detection methods followed by sequencing analysis.

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Nestleroth. PR-337-063508-R01 Dual Field Magnetic Flux Leakage (MFL) Inspection Technology to Detect Mechanical Damage. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), marzec 2013. http://dx.doi.org/10.55274/r0010575.

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This report details the development and testing of a dual magnetization in-line inspection (ILI) tool for detecting mechanical damage in operating pipelines, including the first field trials of a fully operational dual-field magnetic flux leakage (MFL) ILI tool. Augmenting routine MFL corrosion inspection of pipelines using high magnetic fields, this in-line inspection technique detects and assesses mechanical damage using a second lower magnetic field. Nearly all commercially available MFL tools use high magnetic fields to detect and size metal loss such as corrosion. A lower field than commonly applied for detecting metal loss is appropriate for detecting mechanical damage, such as the metallurgical changes caused by impacts from excavation equipment. The lower field is needed to counter the saturation effect of the high magnetic field, which masks and diminishes important components of the signal associated with mechanical damage. At low fields, other properties such as pipeline chemical composition, grain structure, and fabrication methods can also be detected.

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Bruce, Berg i Agrawald. L52304 Development of Criteria-Guidelines for Welding Onto In-Service Chemical Pipelines. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), wrzesień 2009. http://dx.doi.org/10.55274/r0010678.

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Welding onto in-service pipelines and piping systems allows cost-effective installation of branchconnections (hot taps) and repair sleeves. Beyond the normal in-service welding concerns ofburnthrough and hydrogen cracking, there are often additional concerns when welding ontopipelines and piping systems in chemical service. For example, some products can undergochemical changes when exposed to the heat from an in-service weld. In spite of these concerns,some companies routinely weld on lines in chemical and other potentially hazardous service,although limitations and special precautions are often specified. Examples include wallthickness limitations below which in-service welding is not permitted and the use of weldingprocedures that limit heat input. The objective of this project was to review the concerns forwelding on in-service pipelines in chemical service, the techniques that have been used in thepast to address these concerns, and to develop criteria that will allow this type of welding to becarried out safely. Criteria for in-service welding were developed for a wide range of chemicals that were identified as being of interest. The format for these criteria is similar to material safety data sheets (MSDSs). Many of the potential concerns that were identified can be controlled by limiting the inside surface temperature. Factors that affect inside surface temperature include: (1) pipe wall thickness, (2) the introduction of heat into the pipe wall by the welding process, and (3) the removal of heat by the contents. For many of the concerns that were identified, if protection from burnthrough using the inside surface temperature approach is practiced, protection from these other concerns is also accomplished. The ability to accurately control heat input levels is an important aspect of being able to weld safely onto in-service pipelines, particularly when inside surface temperature needs to be limited. Methods for controlling heat input levels in the field were reviewed and detailed guidance was developed. The benefits of using small-diameter electrodes (lower current levels), which allows the attachment of a hot tap fittings at relatively low heat input levels, were identified. Techniques to address other concerns that are not inside surface temperature related were also identified.

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