Artykuły w czasopismach: „Sub-surface profile”

1

Wahid, Nur Syahirah, Norihan Md Arifin, Mustafa Turkyilmazoglu, Mohd Ezad Hafidz Hafidzuddin i Nor Aliza Abd Rahmin. "MHD Hybrid Cu-Al₂O₃/ Water Nanofluid Flow with Thermal Radiation and Partial Slip Past a Permeable Stretching Surface: Analytical Solution". Journal of Nano Research 64 (listopad 2020): 75–91. http://dx.doi.org/10.4028/www.scientific.net/jnanor.64.75.

Pełny tekst źródła

Streszczenie:

The influence of velocity slip and thermal radiation effects on the magnetohydrodynamic hybrid Cu-Al2O3/water nanofluid flow over a permeable stretching sheet is reported in this paper. The similarity transformation is adopted to reduce the partial differential equations to the ordinary differential equations. Exact analytical method is implemented to solve the problem. Maple program is used to facilitate the calculation process. The new additional effects which are the velocity slip and thermal radiation effects are considered towards the model to scrutinize the impacts. The effects of various parameters towards the velocity and temperature profiles are demonstrated through graphs, meanwhile the skin friction coefficient and the local Nusselt number are exhibited through the tabulation of data. The existence of velocity slip reduced the velocity profile but enhanced the temperature profile. The thermal radiation effect has increased the temperature profile. The heat transfer rate are enhanced for the case of hybrid nanofluid compared to the mono nanofluid.

Style APA, Harvard, Vancouver, ISO itp.

2

KIM, DONG-YEOL, HAK-JOON KIM, SUNG-JIN SONG i SUNG D. KWON. "EVALUATION OF SUB-SURFACE MATERIAL PROPERTIES USING MINIMUM REFLECTION PROFILES METHOD". Modern Physics Letters B 22, nr 11 (10.05.2008): 983–88. http://dx.doi.org/10.1142/s0217984908015711.

Pełny tekst źródła

Streszczenie:

Backscattered Rayleigh waves from the surface and/or sub-surface of specimens can be changed by scatterers such as micro-cracks, grain boundaries and surface roughness as well as by variations in material properties. In fact, rough surface generates higher energy of backscattered Rayleigh wave than smooth one. So, it is strongly needed to have a quantitative method to evaluate the variation of material properties only. To address such a need, we propose a new method, named as "minimum reflection profile" which measures energy variation of reflected waves from the surface of specimens as changing the angle of incident wave from normal to beyond Rayleigh angle in a pitch-catch immersion setup. Because of minimum reflection profile is less sensitive to roughness of surface than backward radiation profile. Also, we explore performance of the minimum reflection profiles by evaluating the sub-surface material properties of well known materials with various material properties.

Style APA, Harvard, Vancouver, ISO itp.

3

Lindsey, Kevin, Stuart T. Smith i Colin J. Robbie. "Sub-Nanometre Surface Texture and Profile Measurement with NANOSURF 2". CIRP Annals 37, nr 1 (1988): 519–22. http://dx.doi.org/10.1016/s0007-8506(07)61691-6.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

4

Invernizzi, Laurent, Nader Sadeghi, Florent P. Sainct i Philippe Guillot. "Study of He + 0.2% O₂ plasma jet impinging on liquid surface from He(2³S₁) metastable atoms density measurements". Plasma Sources Science and Technology 31, nr 3 (1.03.2022): 035002. http://dx.doi.org/10.1088/1361-6595/ac4e21.

Pełny tekst źródła

Streszczenie:

Abstract This work presents spatial variations of the helium He(23S1) metastable atom absolute densities in a plasma jet at atmospheric pressure in He + 0.2% O2 gas mixture impinging on a liquid target. The plasma jet is ignited with 6 kV pulses of 2.5 μs duration and 8 ns rise and fall times at 20 kHz repetition rate. Streamers are created in both rising and falling fronts of the high voltage (HV). From Abel inversion of the line averaged absorbance of 1083 nm helium line, measured by laser absorption spectroscopy, the radial profiles of He(23S1) density along the plasma jet are deduced in two sources with different residence time of the gas within the discharge volume, having three different outlet tube diameters and with two gas flow rates. The metastable densities up to ∼3 × 1013 cm−3 have been measured. The radial profile remained always axially centered for the 1.5 mm outlet tube and with 0.5 slm for the larger diameter tubes. But in this later tubes and with 2 slm gas flow rate, the profile changed from a ring shape at the tube exit to axially centered when increasing the distance from the tube edge. In the rising front of the HV, the ring profile of He(23S1) density in the tube exit is attributed to the shape of the electric field, produced by the applied HV to the electrode wrapped around the dielectric tube. In the falling front of the HV, the electric field results from electrons deposited on the inner surface of the dielectric tube and positive ions accumulated on the surface of liquid during the 2.5 μs duration of the HV pulse. The influence of oxygen by-products formed in the plasma volume (O, O2(Δ), O3, positive and negative oxygen ions) on the dynamic of the plasma jet are analyzed.

Style APA, Harvard, Vancouver, ISO itp.

5

Kang, W. T., M. N. Derani i M. M. Ratnam. "Effect of Vibration on Surface Roughness in Finish Turning: Simulation Study". International Journal of Simulation Modelling 19, nr 4 (5.12.2020): 595–606. http://dx.doi.org/10.2507/ijsimm19-4-531.

Pełny tekst źródła

Streszczenie:

This paper presents the results of simulation analyses carried out to investigate the effect of adding controlled vibration of varying amplitudes and frequencies onto simulated workpiece profiles on surface roughness. The surface profiles were generated using the nose edge image of a real cutting tool insert at various stages of wear. The invariant moment sub-pixel edge detection method was used to extract the precise tool nose profile. The extracted nose profile was duplicated 20 times to generate the simulated workpiece profile. Vibration signals in the form of sine waves of amplitudes 0 to 50 % of the peak-to-valley height of the original workpiece profile and various frequencies were added to the simulated profile. Noise signals emanating from real machining were also added to the original profile to investigate their effect on roughness. The simulation study has shown that average roughness may increase continuously or fluctuate randomly depending on the magnitude of vibration added to the vibration-free workpiece profile. In the absence of vibration, the surface roughness of the workpiece decreases due to flattening effect of the tool nose during early stages of tool wear.

Style APA, Harvard, Vancouver, ISO itp.

6

Dartnell, L. R., L. Desorgher, J. M. Ward i A. J. Coates. "Martian sub-surface ionising radiation: biosignatures and geology". Biogeosciences Discussions 4, nr 1 (9.02.2007): 455–92. http://dx.doi.org/10.5194/bgd-4-455-2007.

Pełny tekst źródła

Streszczenie:

Abstract. The surface of Mars, unshielded by thick atmosphere or global magnetic field, is exposed to high levels of cosmic radiation. This ionizing radiation field is deleterious to the survival of dormant cells or spores and the persistence of molecular biomarkers in the subsurface, and so its characterisation is of prime astrobiological interest. Previous research has attempted to address the question of biomarker persistence by inappropriately using dose profiles weighted specifically for cellular survival. Here, we present modelling results of the unmodified physically absorbed radiation dose as a function of depth through the Martian subsurface. A second major implementation of this dose accumulation rate data is in application of the optically stimulated luminescence technique for dating Martian sediments. We present calculations of the dose-depth profile from galactic cosmic rays in the Martian subsurface for various scenarios: variations of surface composition (dry regolith, ice, layered permafrost), solar minimum and maximum conditions, locations of different elevation (Olympus Mons, Hellas basin, datum altitude), and increasing atmospheric thickness over geological history. We also model the changing composition of the subsurface radiation field with depth compared between Martian locations with different shielding material, determine the relative dose contributions from primaries of different energies, and briefly treat particle deflection by the crustal magnetic fields.

Style APA, Harvard, Vancouver, ISO itp.

7

Aras, Eyyup. "Tracing sub-surface swept profiles of tapered toroidal end mills between level cuts". Journal of Computational Design and Engineering 6, nr 4 (18.04.2019): 629–46. http://dx.doi.org/10.1016/j.jcde.2019.04.003.

Pełny tekst źródła

Streszczenie:

Abstract Development of closed-form solutions and algorithms for constructing sub-surface swept profiles (SWP) of toroidal and conical bodies is presented in this paper. While the problem of identifying the entire SWP of such surfaces has been extensively investigated in extant studies, construction of subsurface SWPs has rarely been addressed despite the subject being of great significance to machining process employing nonstandard-shaped NC tools. Torus shapes considered in extant literature are restricted to the fourth quadrant of a tube cross section. In industrial applications, however, profile cutters contain different regions of a toroidal surface. To identify SWP elements in the proposed study, a single analytical expression in one variable has been deduced using two moving frames. The basic idea behind such a formulation is to employ the one-to-many strategy, which greatly reduces the computational cost and effort. Algorithms to identify feasible domains of SWP parameters at each level cut, where toroidal and conical surfaces meet, have also been proposed in this study. This is important, since cutting a tool surfaces along the rotation axis divides SWP-parameter domains into non overlapping sets of intervals that must be addressed for each tool posture. In addition, this study demonstrates that for certain tool postures, while C1 continuity between sub-surfaces is satisfied, the SWP connectivity is lost at some points. To locate these so called singular-characteristic points, some precomputation steps have been performed. Lastly, several factors affecting the smoothness of SWPs have been identified and discussed. Highlights Closed form solutions have been derived for constructing the sub-swept profiles of toroidal tools. Three algorithms have been presented to identify the feasible domains of swept profile parameters. In order to locate the singular-characteristic points some precomputation steps have been carried out. Finally, several factors, affecting the smoothness of the swept profiles, have been identified.

Style APA, Harvard, Vancouver, ISO itp.

8

Zhang, Chang Juan, Chuan Shao Liu i Bo Zhao. "Experimental Study on Surface Quality of Al₂O₃ Engineering Ceramics in Ultrasonic Drilling and Grinding". Applied Mechanics and Materials 42 (listopad 2010): 457–60. http://dx.doi.org/10.4028/www.scientific.net/amm.42.457.

Pełny tekst źródła

Streszczenie:

Engineering ceramics have been widely used in recent years because of its excellent performances. However, the high hardness and brittleness make it very difficult to process with high efficiency and good quality, especially in precision and ultraprecision machining. Therefore, a method of ultrasonic drilling and grinding is provided to the hole machining of Al¬2O3 engineering ceramics. In the paper, with different machining parameters, the surface roughness of micro hole in ultrasonic and traditional drilling and grinding is compared and analyzed. Moreover, the surface micro profile and the wear condition of drilling-grinding tool in ultrasonic and traditional drilling and grinding are observed through SEM. Finally, it is concluded that ultrasonic drilling and grinding is a kind of high efficient processing method adapting to micro holes of hard - brittle materials etc.

Style APA, Harvard, Vancouver, ISO itp.

9

Rahman, A. Azizur, Emroj Hossian, Hetal Vaishnav, Jayesh B. Parmar, Arnab Bhattacharya i Arun Sarma. "Synthesis and characterization of Cu3SbS4 thin films grown by co-sputtering metal precursors and subsequent sulfurization". Materials Advances 1, nr 9 (2020): 3333–38. http://dx.doi.org/10.1039/d0ma00574f.

Pełny tekst źródła

Streszczenie:

X-ray diffraction profile, Raman and optical absorption spectra, and surface morphology of phase-pure Cu₃SbS₄ films grown at 425 °C by co-sputtering metal precursors and subsequent sulfurization.

Style APA, Harvard, Vancouver, ISO itp.

10

H S, Nithin, Pradeep D G, Nishchitha K M, Mahantayya Mathapati, Chikodi . i Anand Babu K. "Comparative study on high temperature oxidation behaviour of CoCrAlY coatings by various reinforcement composition profile analysis". Journal of Mines, Metals and Fuels 69, nr 12A (28.04.2022): 207. http://dx.doi.org/10.18311/jmmf/2021/30104.

Pełny tekst źródła

Streszczenie:

In this article, high temperature oxidation behaviour of plasma sprayed carbides and oxides reinforced composite CoCrAlY coatings were investigated at 700°C. CoCrAlY was reinforced with Al2O3+YSZ, CeO2, WC-Co, Cr3C2-NiCr individually to produce four different coatings. SEM, EDS and XRD are used to analyze the oxide scales formed during oxidation process on the coatings surface. From the results it is found that, all these coatings exhibited parabolic weight gain nature, indicating presence of protective oxide scale on coating surface, whereas changes in total weight gain is observed. CoCrAlY+Al2O3+YSZ coatings exhibited higher oxidation resistance than other coatings. The distribution of thermodynamically stable á- Al2O3 in the coating is shown slow-scale growth kinetics during the oxidation.

Style APA, Harvard, Vancouver, ISO itp.

11

Pan, Guo-Hui, Huajun Wu, Shuai He, Liangliang Zhang, Zhendong Hao, Xia Zhang i Jiahua Zhang. "Dye-embedded YAG:Ce3+@SiO2 composite phosphors toward warm wLEDs through radiative energy transfer: preparation, characterization and luminescence properties". Nanoscale 10, nr 47 (2018): 22237–51. http://dx.doi.org/10.1039/c8nr07360k.

Pełny tekst źródła

Streszczenie:

Surface SiO₂ coating and simultaneous dye embedding in micro/nano-YAG:Ce³⁺ phosphors toward Ce³⁺ spectral profile tailoring through radiative energy transfer is demonstrated.

Style APA, Harvard, Vancouver, ISO itp.

12

Kuzin, V. V., S. N. Grigor’ev i M. A. Volosova. "Correlation between the profile of the working surface of the diamond wheel and the quality of the ground surface of Аl₂О₃‒TiC-ceramics". NOVYE OGNEUPORY (NEW REFRACTORIES), nr 11 (18.02.2021): 64–70. http://dx.doi.org/10.17073/1683-4518-2020-11-64-70.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

13

Lamsal, L. N., N. A. Krotkov, E. A. Celarier, W. H. Swartz, K. E. Pickering, E. J. Bucsela, R. V. Martin i in. "Evaluation of OMI operational standard NO2 column retrievals using in situ and surface-based NO2 observations". Atmospheric Chemistry and Physics Discussions 14, nr 10 (5.06.2014): 14519–73. http://dx.doi.org/10.5194/acpd-14-14519-2014.

Pełny tekst źródła

Streszczenie:

Abstract. We assess the standard operational nitrogen dioxide (NO2) data product (OMNO2, version 2.1) retrieved from the Ozone Monitoring Instrument (OMI) onboard NASA's Aura satellite using a combination of aircraft and surface in situ measurements as well as ground-based column measurements at several locations and a bottom-up NOx emission inventory over the continental US. Despite considerable sampling differences, NO2 vertical column densities from OMI are modestly correlated (r = 0.3–0.8) with in situ measurements of tropospheric NO2 from aircraft, ground-based observations of NO2 columns from MAX-DOAS and Pandora instruments, in situ surface NO2 measurements from photolytic converter instruments, and a bottom-up NOx emission inventory. Overall, OMI retrievals tend to be lower in urban regions and higher in remote areas, but generally agree with other measurements to within ± 20%. No consistent seasonal bias is evident. Contrasting results between different data sets reveal complexities behind NO2 validation. Monthly mean vertical NO2 profile shapes from the Global Modeling Initiative (GMI) chemistry-transport model (CTM) used in the OMI retrievals are highly consistent with in situ aircraft measurements, but these measured profiles exhibit considerable day-to-day variation, affecting the retrieved daily NO2 columns by up to 40%. This assessment of OMI tropospheric NO2 columns, together with the comparison of OMI-retrieved and model-simulated NO2 columns, could offer diagnostic evaluation of the model.

Style APA, Harvard, Vancouver, ISO itp.

14

Dartnell, L. R., L. Desorgher, J. M. Ward i A. J. Coates. "Martian sub-surface ionising radiation: biosignatures and geology". Biogeosciences 4, nr 4 (30.07.2007): 545–58. http://dx.doi.org/10.5194/bg-4-545-2007.

Pełny tekst źródła

Streszczenie:

Abstract. The surface of Mars, unshielded by thick atmosphere or global magnetic field, is exposed to high levels of cosmic radiation. This ionising radiation field is deleterious to the survival of dormant cells or spores and the persistence of molecular biomarkers in the subsurface, and so its characterisation is of prime astrobiological interest. Here, we present modelling results of the absorbed radiation dose as a function of depth through the Martian subsurface, suitable for calculation of biomarker persistence. A second major implementation of this dose accumulation rate data is in application of the optically stimulated luminescence technique for dating Martian sediments. We present calculations of the dose-depth profile in the Martian subsurface for various scenarios: variations of surface composition (dry regolith, ice, layered permafrost), solar minimum and maximum conditions, locations of different elevation (Olympus Mons, Hellas basin, datum altitude), and increasing atmospheric thickness over geological history. We also model the changing composition of the subsurface radiation field with depth compared between Martian locations with different shielding material, determine the relative dose contributions from primaries of different energies, and discuss particle deflection by the crustal magnetic fields.

Style APA, Harvard, Vancouver, ISO itp.

15

Breen, Peter F., i Alan J. Chick. "Rootzone dynamics in constructed wetlands receiving wastewater: a comparison of vertical and horizontal flow systems". Water Science and Technology 32, nr 3 (1.08.1995): 281–90. http://dx.doi.org/10.2166/wst.1995.0150.

Pełny tekst źródła

Streszczenie:

Profile conditions were examined in both small experimental and pilot scale sub-surface flow wetlands. The study systems differed in their hydraulic design. The experimental systems had a vertical up-flow design whereas the pilot system was a horizontal flow trench design. Both systems were found to have significant physical, chemical and biological gradients within the sub-surface profile. System age and plant root density appear to be important factors in determining profile differentiation within the experimental systems. Root densities were found to be partitioned between the upper and lower layers on a 70%/30% split, respectively. However, in the experimental systems as the systems aged and root densities increased beyond 112-251 g.m−2 chemical water quality differentiation in the profile disappeared. Pilot scale systems were found to have physical gradients within the profile as evidenced by hydraulic short-circuiting. Vertical root density distribution is proposed as a major cause of this condition in horizontal flow systems.

Style APA, Harvard, Vancouver, ISO itp.

16

Sujak, Muhammad, i Dede Djuhana. "Investigation to Localized Surface Plasmon Resonance Properties of Non-Noble Metals: Fe, Ni, and Ni₈₀Fe₂₀". Key Engineering Materials 855 (lipiec 2020): 243–47. http://dx.doi.org/10.4028/www.scientific.net/kem.855.243.

Pełny tekst źródła

Streszczenie:

In this work, we have investigated the localized surface plasmon resonance profile of promising non-noble metals such as nickel (Ni), iron (Fe), and permalloy (Ni80Fe20) as an alternative plasmonic material. The nanoparticle formed a sphere with varying the diameter from 10 nm to 200 nm with increment 10 nm, and the medium of nanoparticles is air (1+0i). The calculation was carried out by metallic nanoparticle boundary element method package. Furthermore, our result shows that increasing diameter of particles (iron, nickel, and permalloy) would increase the efficiency of ratio scattering to absorption, and the LSPRs peak led to shift to lower energy (red-shift). The ratio of scattering to absorption indicates a strengthening of radiative damping in large particle-size which largely used in biological cell imaging. However, iron’s efficiency much lower than nickel and permalloy. For example, at the highest diameter, such 200 nm, the efficiency of iron is just over around 1.25 while nickel and permalloy well under nearly 2.0. In addition, nickel and permalloy’s LSPR happened in visible range. Our results serve a systematic understanding of the shifting spectrum pattern for prospective ferromagnetic materials

Style APA, Harvard, Vancouver, ISO itp.

17

Ali, Mubarak, E. Hamzah, I. A. Qazi i M. R. M. Toff. "Growth Defects and Surface Roughness in TiN-Coated Tool Steel at Various N₂ Gas Flow Rates Using Cathodic Arc PVD Technique". Materials Science Forum 636-637 (styczeń 2010): 965–70. http://dx.doi.org/10.4028/www.scientific.net/msf.636-637.965.

Pełny tekst źródła

Streszczenie:

In the present study, titanium nitride coatings on tool steel were deposited using cathodic arc physical vapour deposition technique. We studied and discussed the effect of various nitrogen gas flow rate on the surface properties of TiN-coated steel. The coating properties investigated in this work include the surface morphology, surface roughness, line profile and fractal dimension analyses using atomic force microscope. Minimum values for surface roughness, line profile and fractal dimension analyses were recorded at nitrogen gas flow rate of 200 sccm. This is mainly because of the reduction in macro-droplets and minimization of the growth defects, usually produced during etching and deposition stages. Critical limit of nitrogen gas flow rate in TiN coatings were identified and considered an important aspect to understand the performance of TiN PVD-coated steel.

Style APA, Harvard, Vancouver, ISO itp.

18

Chettri, Nimesh, Indra Bdr.Chhetri i Karma Yangzom. "Profile of subgrade subsidence in Sorchen". International Journal on Integrated Education 2, nr 6 (9.12.2019): 47–54. http://dx.doi.org/10.31149/ijie.v2i6.197.

Pełny tekst źródła

Streszczenie:

The highway along Sorchen have been imperiled to various mechanical damages posing tremendous problems to the road users. These damages of road and its sub-grade are contributed by number of factors both manmade and natural. This research focuses on identification of damaged subgrade and its causes to the measurable degree. The greater emphasis has been turned to the Geotechnical site investigation of the affected areas and quantification of the results for the benefit of the policy makers in future. The survey has been carried out to ensure the extend of subsidence of the road and shown in the graphical manner. Wenner’s 4 Spikes method ground resistivity test were also carried out to explore the sub surface of the affected subgrade. The research has also done on the possibilities of rigid slab supported by the pile foundation as the counter measures. The results obtained by the electrical resistivity test will be used to located the depth of pile foundation.

Style APA, Harvard, Vancouver, ISO itp.

19

Lamsal, L. N., N. A. Krotkov, E. A. Celarier, W. H. Swartz, K. E. Pickering, E. J. Bucsela, J. F. Gleason i in. "Evaluation of OMI operational standard NO2 column retrievals using in situ and surface-based NO2 observations". Atmospheric Chemistry and Physics 14, nr 21 (5.11.2014): 11587–609. http://dx.doi.org/10.5194/acp-14-11587-2014.

Pełny tekst źródła

Streszczenie:

Abstract. We assess the standard operational nitrogen dioxide (NO2) data product (OMNO2, version 2.1) retrieved from the Ozone Monitoring Instrument (OMI) onboard NASA's Aura satellite using a combination of aircraft and surface in~situ measurements as well as ground-based column measurements at several locations and a bottom-up NOx emission inventory over the continental US. Despite considerable sampling differences, NO2 vertical column densities from OMI are modestly correlated (r = 0.3–0.8) with in situ measurements of tropospheric NO2 from aircraft, ground-based observations of NO2 columns from MAX-DOAS and Pandora instruments, in situ surface NO2 measurements from photolytic converter instruments, and a bottom-up NOx emission inventory. Overall, OMI retrievals tend to be lower in urban regions and higher in remote areas, but generally agree with other measurements to within ± 20%. No consistent seasonal bias is evident. Contrasting results between different data sets reveal complexities behind NO2 validation. Since validation data sets are scarce and are limited in space and time, validation of the global product is still limited in scope by spatial and temporal coverage and retrieval conditions. Monthly mean vertical NO2 profile shapes from the Global Modeling Initiative (GMI) chemistry-transport model (CTM) used in the OMI retrievals are highly consistent with in situ aircraft measurements, but these measured profiles exhibit considerable day-to-day variation, affecting the retrieved daily NO2 columns by up to 40%. This assessment of OMI tropospheric NO2 columns, together with the comparison of OMI-retrieved and model-simulated NO2 columns, could offer diagnostic evaluation of the model.

Style APA, Harvard, Vancouver, ISO itp.

20

Harahap, Ilham Pradana Putra, i Dian Novita. "IDENTIFY MISCONCEPTION ON REACTION RATE CONCEPT USING FOUR-TIER MULTIPLE CHOICE (4TMC) DIAGNOSTIC TEST INSTRUMENT". JCER (Journal of Chemistry Education Research) 5, nr 1 (29.06.2021): 6. http://dx.doi.org/10.26740/jcer.v5n1.p6-11.

Pełny tekst źródła

Streszczenie:

Abstract. The aims of this study to identify the profile of students’ conseptions and misconceptions on the concept of reaction rate using a four-tier multiple choice diagnostic test instrument reported in the form of misconception profiles consisting of students' conceptions, students' misconceptions and the causes of misconceptions experienced by students. Based on the results of the study shown (1) the students’ conception profile is as much as 78% understand the concept, 21% misconceptions and 1% do not understand the concept, (2) the profile of student’s misconceptions in each sub-material that misconceptions on sub-material of concentration 16%, temperature 19%, surface area 41% and catalyst 24% and as many as 1 student (3%) including the high misconception category, 22 students (67%) included in the medium misconception category and 10 students (30%) were in the low misconception category. Students’ misconceptions vary in different causes such as; associative thinking 59%, preconceptions 25%, incomplete resoning 13%, humanistic thinking 2% and incorrect intuition 1% . Keywords: four-tier multiple choice, misconception, reaction rate

Style APA, Harvard, Vancouver, ISO itp.

21

Ghobadi, Nader, i Ebrahim Gholami Hatam. "Optical band gap, photocatalysis, surface structures and depth profile properties of Cu₂Se nanostructured thin films". Materials Research Express 9, nr 3 (1.03.2022): 035007. http://dx.doi.org/10.1088/2053-1591/ac5f36.

Pełny tekst źródła

Streszczenie:

Abstract The optical behaviour, stoichiometry, surface configuration of Cu2Se nanostructured thin layers prepared at different reaction times by the chemical process has been considered. The optical band gap of the deposited thin films decreases from 2.92 eV to 2.08 eV for the first transition and from 2.18 to 1.2 eV for the second transition. In addition, it was shown that Urbach energy is independent from the film thickness, and tail values of the localized states has decreased from 1.15 to 0.33 eV. It was found that the concentration of Cu: Se remains approximately constant across the depth of the deposited film at higher deposition time. The degradation efficiency of 98% was achieved by Congo red for the prepared Cu2Se thin film at optimal condition which make it a good candidate for organic dye. From these measurements and by controlling the band gap energy, the Cu2Se can find application in solar cell application.

Style APA, Harvard, Vancouver, ISO itp.

22

Cecchin, Diego, Cristy Leonor Azanza Ricardo, Mirco D'Incau, Michele Bandini i Paolo Scardi. "Influence of Shot-Peening Parameters on the Sub-Surface Residual Stress Profiles in Al-7075 Alloy Components". Materials Science Forum 768-769 (wrzesień 2013): 66–71. http://dx.doi.org/10.4028/www.scientific.net/msf.768-769.66.

Pełny tekst źródła

Streszczenie:

Aluminum alloy (Al-7075-T6) samples were analyzed to determine the in-depth residual stress profile induced by a shot-peening treatment. The influence of coverage degree and Almen intensity on the surface residual stress and on the sub-surface residual stress gradient was investigated. Residual stress profiles were obtained using three different techniques: (i) standard laboratory X-ray diffraction (XRD) residual stress analysis with progressive chemical layer-removal; (ii) XRD residual stress analysis with synchrotron radiation using different X-ray energies, thus changing the penetration depths, and (iii) Blind Hole Drilling (BHD). A comprehensive comparison of the results given by the used techniques is shown.

Style APA, Harvard, Vancouver, ISO itp.

23

Scanlon, B., G. A. Wick i B. Ward. "Near-surface diurnal warming simulations: validation with high resolution profile measurements". Ocean Science Discussions 9, nr 6 (20.12.2012): 3851–78. http://dx.doi.org/10.5194/osd-9-3851-2012.

Pełny tekst źródła

Streszczenie:

Abstract. Sea surface temperature (SST) is an important property for governing the exchange of energy between the ocean and the atmosphere. Common in-situ methods of measuring SST often require a cool-skin and warm-layer adjustment in the presence of diurnal warming effects. A critical requirement for an ocean sub-model is that it can simulate the change in SST over diurnal, seasonal, and annual cycles. In this paper we use high-resolution near-surface profiles of SST to validate simulated near-surface temperature profiles from a modified version of the Kantha and Clayson 1-D mixed layer model. Additional model enhancements such as the incorporation of a parameterisation of turbulence generated by wave breaking and a solar absorption model are also validated. The model simulations show a strong variability in highly stratified conditions, with different models providing the best results depending on the specific criteria and conditions. In general, the models with enhanced wave breaking effects tended to underestimate the temperature profile measurements while the more coarse baseline and blended approaches produced the most accurate comparisons with the in-situ SST data.

Style APA, Harvard, Vancouver, ISO itp.

24

Rosicky, Mark A., Peter Slavich, Leigh A. Sullivan i Mike Hughes. "Surface and sub-surface salinity in and around acid sulfate soil scalds in the coastal floodplains of New South Wales, Australia". Soil Research 44, nr 1 (2006): 17. http://dx.doi.org/10.1071/sr05027.

Pełny tekst źródła

Streszczenie:

Two-metre-deep soil profiles at 10 acid sulfate soil (ASS) scalds along the coast of New South Wales (NSW), Australia, were examined for salinity indicators. At 5 of the sites, permanently vegetated areas adjacent to the ASS-scalded land were also tested. Throughout the profiles, most sites had high soluble chloride (Cl−) concentrations (≤17 mg/g soil) and high soluble sulfate (SO42−) concentrations (≤17 mg/g soil). Very low Cl− : SO42− ratios (≤3) indicated active pyrite oxidation. Soil salinity (measured as electrical conductivity, EC) was extremely high in the top 2 m of most of the ASS scalds when related to the growth requirements of the typical introduced pasture species that were planted in these areas following drainage. This allows salinity, in addition to the extremely low pH of the surface soils, to contribute to land denudation, which can instigate or perpetuate pyrite oxidation and ASS-related land scalding. Although the sites had shallow watertables and soil-moisture content was high, the surface soil (top 0.10 m) of the scalds had consistently higher soluble Cl− and SO42− concentrations and EC than adjacent vegetated areas. All coastal ASS areas investigated, typically freshwater backswamps used for cattle grazing, were underlain by estuarine-derived sediments containing saline ground water. The results demonstrate that revegetation of ASS scalds must include investigation and management of salinity, in addition to acidity, within the soil profile and at the soil surface.

Style APA, Harvard, Vancouver, ISO itp.

25

Heidt, J., T. Pursimo, A. Sillanpää, L. O. Takalo i K. Nilsson. "High-Resolution Imaging of BL LAC Host Galaxies". Symposium - International Astronomical Union 171 (1996): 389. http://dx.doi.org/10.1017/s0074180900233081.

Pełny tekst źródła

Streszczenie:

We present high-resolution imaging of the BL Lac objects 1ES 0229+200 (z = 0.14), Markarian 421 (z = 0.031) and the prototype BL Lac (z = 0.069). Our goal is to study the properties of the host galaxies of this enigmatic sources and to compare them with their non-actice counterparts. The observations were carried out with the Nordical Optical Telescope (NOT) at La Palma under sub-arcsecond seeing conditions (FWHM < 0.″8). The surface brightness profiles of the host galaxies were analyzed as described in Bender and Möllenhoff (A&A, 177, 71 (1987)). After masking the disturbing field stars/galaxies isophotes were fitted by ellipses down to 20.5 mag/arccsec2 in Markarian 421, 23.5 mag/arcsec2 in BL Lac and 25.5 mag/arcsec2 in 1ES 0229+200. Additionally, we analyzed the surface brightness profile of the companion of Markarian 421.The surface brightness profiles of the host galaxies were analyzed as described in Bender and Möllenhoff (A & A, 177, 71 (1987)). After masking the disturbing field stars/galaxies isophotes were fitted by ellipses down to 20.5 mag/arccsec2 in Markarian 421, 23.5 mag/arccsec2 in BL Lac and 25.5 mag/arccsec2 in 1ES 0229+200. Additionally, we analyzed the surface brightness profile of the companion of Markarian 421.

Style APA, Harvard, Vancouver, ISO itp.

26

Ženišová, Z., P. P. Povinec, A. Šivo, R. Breier, M. Richtáriková, A. Ďuričková i A. L'uptáková. "Hydrogeochemical and isotopic characterization of groundwater at Žitný Island (SW Slovakia)". Hydrology Research 46, nr 6 (21.01.2015): 929–42. http://dx.doi.org/10.2166/nh.2015.187.

Pełny tekst źródła

Streszczenie:

Hydrogeochemical investigations and spatial variations studies on the distribution of water isotopes and radiocarbon in the groundwater of Žitný Island (Rye Island) were carried out. Žitný Island represents the largest groundwater reservoir in Central Europe (about 10 Gm3). The chemical composition of the groundwater of Žitný Island depends mainly on the chemical composition of Danube water, as well as on the length of its infiltration from the Danube River. The groundwater is characterized by potamogenic mineralization, and its chemical composition is influenced by anthropogenic contamination. Sub-surface water profiles showed enriched δ18O levels up to around 20 m water depth, and depleted values for deeper waters. The observed isotopic composition of the groundwater is similar to Danube water, suggesting that the Danube River is the main source of the Žitný Island groundwater. The core of the sub-surface 14C profile represents contemporary groundwater with 14C values above 80 pMC.

Style APA, Harvard, Vancouver, ISO itp.

27

Gao, Xiang, Rong Qiu, Kunpeng Wang, Jiangmei Zhang, Guorui Zhou, Ke Yao, Yong Jiang i Qiang Zhou. "The size prediction of potential inclusions embedded in the sub-surface of fused silica by damage morphology". Open Physics 15, nr 1 (30.04.2017): 233–39. http://dx.doi.org/10.1515/phys-2017-0025.

Pełny tekst źródła

Streszczenie:

AbstractA model for predicting the size ranges of different potential inclusions initiating damage on the surface of fused silica has been presented. This accounts for the heating of nanometric inclusions whose absorptivity is described based on Mie Theory. The depth profile of impurities has been measured by ICP-OES. By the measured temporal pulse profile on the surface of fused silica, the temperature and thermal stress has been calculated. Furthermore, considering the limit conditions of temperature and thermal stress strength for different damage morphologies, the size range of potential inclusions for fused silica is discussed.

Style APA, Harvard, Vancouver, ISO itp.

28

Haszpra, L., M. Ramonet, M. Schmidt, Z. Barcza, Z. Pátkai, K. Tarczay, C. Yver, J. Tarniewicz i P. Ciais. "Variation of CO2 mole fraction in the lower free troposphere, in the boundary layer and at the surface". Atmospheric Chemistry and Physics Discussions 12, nr 5 (4.05.2012): 11539–66. http://dx.doi.org/10.5194/acpd-12-11539-2012.

Pełny tekst źródła

Streszczenie:

Abstract. Eight years of occasional flask air sampling and 3 yr of frequent in situ measurements of carbon dioxide (CO2) vertical profiles on board of a small aircraft, over a tall tower greenhouse gases monitoring site in Hungary are used for the analysis of the variations of vertical profile of CO2 mole fraction. Using the airborne vertical profiles and the measurements along the 115 m tall tower it is shown that the measurements at the top of the tower estimate the mean boundary layer CO2 mole fraction during the mid-afternoon fairly well, with an underestimation of 0.27–0.85 μmol mol−1 in summer, and an overestimation of 0.66–1.83 μmol mol−1 in winter. The seasonal cycle of CO2 mole fraction is damped with elevation. While the amplitude of the seasonal cycle is 28.5 μmol mol−1 at 10 m above the ground, it is only 10.7 μmol mol−1 in the layer of 2500–3000 m corresponding to the lower free atmosphere above the well-mixed boundary layer. The maximum mole fraction in the layer of 2500–3000 m can be observed around 25 March on average, two weeks ahead of that of the marine boundary layer reference (GLOBALVIEW). By contrast, close to the ground, the maximum CO2 mole fraction is observed late December, early January. The specific seasonal behavior is attributed to the climatology of vertical mixing of the atmosphere in the Carpathian Basin.

Style APA, Harvard, Vancouver, ISO itp.

29

Haszpra, L., M. Ramonet, M. Schmidt, Z. Barcza, Zs Pátkai, K. Tarczay, C. Yver, J. Tarniewicz i P. Ciais. "Variation of CO2 mole fraction in the lower free troposphere, in the boundary layer and at the surface". Atmospheric Chemistry and Physics 12, nr 18 (28.09.2012): 8865–75. http://dx.doi.org/10.5194/acp-12-8865-2012.

Pełny tekst źródła

Streszczenie:

Abstract. Eight years of occasional flask air sampling and 3 years of frequent in situ measurements of carbon dioxide (CO2) vertical profiles on board of a small aircraft, over a tall tower greenhouse gases monitoring site in Hungary are used for the analysis of the variations of vertical profile of CO2 mole fraction. Using the airborne vertical profiles and the measurements along the 115 m tall tower it is shown that the measurements at the top of the tower estimate the mean boundary layer CO2 mole fraction during the mid-afternoon fairly well, with an underestimation of 0.27–0.85 μmol mol−1 in summer, and an overestimation of 0.66–1.83 μmol mol−1 in winter. The seasonal cycle of CO2 mole fraction is damped with elevation. While the amplitude of the seasonal cycle is 28.5 μmol mol−1 at 10 m above the ground, it is only 10.7 μmol mol−1 in the layer of 2500–3000 m corresponding to the lower free atmosphere above the well-mixed boundary layer. The maximum mole fraction in the layer of 2500–3000 m can be observed around 25 March on average, two weeks ahead of that of the marine boundary layer reference (GLOBALVIEW). By contrast, close to the ground, the maximum CO2 mole fraction is observed late December, early January. The specific seasonal behavior is attributed to the climatology of vertical mixing of the atmosphere in the Carpathian Basin.

Style APA, Harvard, Vancouver, ISO itp.

30

Kvietková, M. "Topography of material made by the application of abrasive water jet technology". Journal of Forest Science 60, No. 8 (1.09.2014): 318–23. http://dx.doi.org/10.17221/7591-jfs.

Pełny tekst źródła

Streszczenie:

Water jet cutting technology is widely applicable in all industrial areas in areas where the need for high dimensional precision machined material. Quality of surface corresponds to the scale from middle smooth milling to rough milling. It shows the results of undulation in dependence on technical and technological parameters ‒ feed rate and abrasive mass flow. The paper also contains the methodology for assessment of the effect of these parameters on surface finished undulation. Our paper presents significant results of experiments made by this methodology applied to MDF, OSB boards and to technical beech plywood. We can see from the above-mentioned results that the fundamental indicator for roughness assessment is the arithmetical mean deviation of roughness profile Ra. MDF boards have the most homogeneous structure in the entire cut among the monitored materials, which affects the insignificance of parameter Ra. For OSB boards, we can see the worse surface quality with higher feed rate and vice versa for plywood, higher feed rate improves the surface quality. A higher amount of abrasive flow causes the worse surface quality.

Style APA, Harvard, Vancouver, ISO itp.

31

Xie, Jin, Junichi Tamaki i Yong Tang. "Arc Envelope Truing of Metal-Bonded Diamond Grinding Wheel by Use of Cone-Shaped Truer". Key Engineering Materials 315-316 (lipiec 2006): 421–24. http://dx.doi.org/10.4028/www.scientific.net/kem.315-316.421.

Pełny tekst źródła

Streszczenie:

This paper introduces a new arc envelop truing method of metal-bonded diamond grinding. It utilizes the arc profile of rotary cone-shaped truer, namely electrode, to envelop wheel profile during Electro-Contact Discharge (ECD) truing. The aim is to realize precision truing of diamond grinding wheel profile for grinding of hard-brittle material. The arc envelope truing principle of wheel profile was analyzed by the use of 3D spatial geometry to identify lean angle of the truer. Then the arc envelop truing and grinding experiments were carried out to investigate truing precision and ground surface in comparison with straight truing and GC stick truing. It was confirmed that the arc envelope truing can obtain sub-micro truing precision of metal-bonded diamond grinding wheel at the depth of cut of micro degree. It may improve greatly form accuracy and ground surface.

Style APA, Harvard, Vancouver, ISO itp.

32

Aibaidula, Abudumijiti(Zack), Cori E. Fain, Luz Cumba Garcia, Miyeon Jung, Aaron J. Johnson i Ian F. Parney. "Multiparametric analysis in GBM plasma extracellular vesicles (Evs) and surface marker expression profile." Journal of Clinical Oncology 40, nr 16_suppl (1.06.2022): 2038. http://dx.doi.org/10.1200/jco.2022.40.16_suppl.2038.

Pełny tekst źródła

Streszczenie:

2038 Background: Glioblastoma (GBM) is the most common malignant brain tumor with poor clinical prognosis. Management of GBM is hampered by the lack of an accurate test that can be used for differential diagnosis of tumor progression from inflammatory pseudoprogression. Plasma extracellular vesicles (EVs) has been shown to be a promising source for biomarker identification. In this project, we aimed to identify GBM plasma EV markers that could serve as the basis of a liquid biopsy. Methods: Sample preparation, assay controls and instrument calibration were performed following MIFlowCyt-EV guideline. Plasma samples were subjected to 2-step centrifugations to remove cell debris and platelets. 10ul of plasma sample was diluted with 90ul filtered PBS, then stained for EV surface markers including CD9, CD31, CD45, CD41a and CD11b, as well as actin phalloidin. Stained plasma samples were purified using IZON qEV1/70nm column, then EV fractions were analyzed using full spectrum Cytek Aurora flow cytometer. Clustering analysis was performed on EV events (CD9 +/ actin phalloidin -) using t-SNE and FlowSOM extensions from FlowJo plugins. Results: Compared to normal donors, GBM plasma EVs were bigger in size (higher SSC value) and expressed higher levels of CD9, CD31, CD45 and CD11b while ND plasma EVs had higher CD41a expression. t-SNE and FlowSOM analysis demonstrated that GBM plasma EVs had a unique surface marker expression profile compared to ND EVs. It also showed 10 EV sub-populations that differed in size as well as various surface marker expression levels. Four of these subpopulations were enriched in GBM EVs, while three of these were enriched in ND EVs. Conclusions: This multiparametric analysis revealed that GBM plasma EVs had a unique surface marker expression profile compared to ND plasma EVs. Further separation and molecular profiling analysis based on each sub population could reveal EV biomarkers that are unique to each sample population.

Style APA, Harvard, Vancouver, ISO itp.

33

Aibaidula, Abudumijiti(Zack), Cori E. Fain, Luz Cumba Garcia, Miyeon Jung, Aaron J. Johnson i Ian F. Parney. "Multiparametric analysis in GBM plasma extracellular vesicles (Evs) and surface marker expression profile." Journal of Clinical Oncology 40, nr 16_suppl (1.06.2022): 2038. http://dx.doi.org/10.1200/jco.2022.40.16_suppl.2038.

Pełny tekst źródła

Streszczenie:

2038 Background: Glioblastoma (GBM) is the most common malignant brain tumor with poor clinical prognosis. Management of GBM is hampered by the lack of an accurate test that can be used for differential diagnosis of tumor progression from inflammatory pseudoprogression. Plasma extracellular vesicles (EVs) has been shown to be a promising source for biomarker identification. In this project, we aimed to identify GBM plasma EV markers that could serve as the basis of a liquid biopsy. Methods: Sample preparation, assay controls and instrument calibration were performed following MIFlowCyt-EV guideline. Plasma samples were subjected to 2-step centrifugations to remove cell debris and platelets. 10ul of plasma sample was diluted with 90ul filtered PBS, then stained for EV surface markers including CD9, CD31, CD45, CD41a and CD11b, as well as actin phalloidin. Stained plasma samples were purified using IZON qEV1/70nm column, then EV fractions were analyzed using full spectrum Cytek Aurora flow cytometer. Clustering analysis was performed on EV events (CD9 +/ actin phalloidin -) using t-SNE and FlowSOM extensions from FlowJo plugins. Results: Compared to normal donors, GBM plasma EVs were bigger in size (higher SSC value) and expressed higher levels of CD9, CD31, CD45 and CD11b while ND plasma EVs had higher CD41a expression. t-SNE and FlowSOM analysis demonstrated that GBM plasma EVs had a unique surface marker expression profile compared to ND EVs. It also showed 10 EV sub-populations that differed in size as well as various surface marker expression levels. Four of these subpopulations were enriched in GBM EVs, while three of these were enriched in ND EVs. Conclusions: This multiparametric analysis revealed that GBM plasma EVs had a unique surface marker expression profile compared to ND plasma EVs. Further separation and molecular profiling analysis based on each sub population could reveal EV biomarkers that are unique to each sample population.

Style APA, Harvard, Vancouver, ISO itp.

34

Pratap, Chandra, Prakash Chandra, Ravi Butola i Anurag Shukla. "Fabrication and Characterization of AA6063/B₄C Metal Matrix Surface Nanocomposite Using Friction Stir Processing". ECS Journal of Solid State Science and Technology 11, nr 3 (1.03.2022): 033010. http://dx.doi.org/10.1149/2162-8777/ac5c81.

Pełny tekst źródła

Streszczenie:

In development of nanocomposite the aims of the present work is to formation of Self-assembled monolayer (SAM) of boron carbide over the surface of AA6063 using via Friction stir processing (FSP). Boron Carbide nano-particle is bonded over the surface of AA6063 followed by FSP technique. To ensure uniform distribution of nanoparticle reinforcement in the grooves a 0.5 molar solution was prepared by dissolving 0.138 g of B4C in 5 ml of diethyl ether (DEE) with enhanced surface and mechanical properties. Two passes on both specimens were performed using the same tool with the tool rotational and traverse speed as 1000 rpm and 40 mm s−1 respectively. For minimizing defects a square tool pin profile with pin length of 3.5 mm and 7.2 mm diagonal. The resultant specimens are studied for the significant changes in tensile strength, ductility, hardness and wear properties due to the addition of reinforcement material and refinement of grain structure. The microstructural graphs supported by SEM and EDS analysis were focused upon to study the composition of nanocomposite prepared. The nanocomposite and FSPed specimen showed an increase in hardness by more than two folds with a negligible decrease in ductility and an appreciable improvement in wear resistance.

Style APA, Harvard, Vancouver, ISO itp.

35

Yang, Ping, Shi-wei Ye i Yun-feng Peng. "Three-dimensional profile stitching measurement for large aspheric surface during grinding process with sub-micron accuracy". Precision Engineering 47 (styczeń 2017): 62–71. http://dx.doi.org/10.1016/j.precisioneng.2016.07.005.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

36

Woon Kiow, Lee, Syed Mohamad Aiman Tuan Muda, Ong Pauline, Sia Chee Kiong, Norfazillah Talib i Aslinda Saleh. "Application of Wavelet Analysis in Tool Wear Evaluation Using Image Processing Method". International Journal of Engineering & Technology 7, nr 4.36 (1.12.2018): 426. http://dx.doi.org/10.14419/ijet.v7i4.36.28155.

Pełny tekst źródła

Streszczenie:

Tool wear plays a significant role for proper planning and control of machining parameters to maintain the product quality. However, existing tool wear monitoring methods using sensor signals still have limitations. Since the cutting tool operates directly on the workpiece during machining process, the machined surface provides valuable information about the cutting tool condition. Therefore, the objective of present study is to evaluate the tool wear based on the workpiece profile signature by using wavelet analysis. The effect of wavelet families, scale of wavelet and statistical features of the continuous wavelet coefficient on the tool wear is studied. The surface profile of workpiece was captured using a DSLR camera. Invariant moment method was applied to extract the surface profile up to sub-pixel accuracy. The extracted surface profile was analyzed by using continuous wavelet transform (CWT) written in MATLAB. The results showed that average, RMS and peak to valley of CWT coefficients at all scale increased with tool wear. Peak to valley at higher scale is more sensitive to tool wear. Haar was found to be more effective and significant to correlate with tool wear with highest R2 which is 0.9301.

Style APA, Harvard, Vancouver, ISO itp.

37

Bourgault du Coudray, P. L., D. R. Williamson i W. D. Scott. "Prediction of chloride leaching from a non-irrigated, de-watered saline soil using the MACRO model". Hydrology and Earth System Sciences 1, nr 4 (31.12.1997): 845–51. http://dx.doi.org/10.5194/hess-1-845-1997.

Pełny tekst źródła

Streszczenie:

Abstract. A pedon scale study was conducted to investigate the degree of chloride leaching from a de-watered saline soil profile in the non-irrigated wheatbelt region of south-western Australia. Within the surface 250mm of the soil profile was a dispersed layer acting as a hydraulic throttle. Soil water tensions and chloride concentrations were obtained over a two-year period over depths ranging from 0.2m to 1.5m. In the first year the soil surface remained untouched. In the second year, the throttle layer was fractured by ripping to a depth of 250mm. Rainfall, runoff and potential evaporation were also measured at the site. These data were used to calibrate and run the MACRO solute transport model using three surface treatment management scenarios: I. the soil surface remains unchanged (`Do nothing'); II. the soil surface is continually ripped; III. the soil surface is ripped followed by surface scaling. The time period required, effectively, to leach the chloride from the profile, to a depth of 1.5m, was predicted. Effective leaching would take at least 400 years and possibly in excess of 200,000 years for Treatment I, 5 years for Treatment II and 90 years for Treatment III. Macropores that were observed within the sub-surface soil profile played no significant role in the leaching of the chloride. However, the rip fractures were treated as macropores by the MACRO model and as such allowed greater infiltration of water that resulted in the mobilisation of chloride within the rest of the soil profile.

Style APA, Harvard, Vancouver, ISO itp.

38

Bisinella, Valentina, Lilja Dahl, Henrik Jensen, Teis N. Mikkelsen i Thomas H. Christensen. "Environmental Profile of NOx Reduction by a Photocatalytic Surface Coating and a Vehicle Catalytic Converter". Journal of Environmental Protection 12, nr 09 (2021): 590–623. http://dx.doi.org/10.4236/jep.2021.129037.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

39

Font, A., J. A. Morguí i X. Rodó. "Assessing the regional surface influence through Backward Lagrangian Dispersion Models for aircraft CO2 vertical profiles observations in NE Spain". Atmospheric Chemistry and Physics Discussions 10, nr 3 (29.03.2010): 8103–34. http://dx.doi.org/10.5194/acpd-10-8103-2010.

Pełny tekst źródła

Streszczenie:

Abstract. A weekly climatology for 2006 composed of 96-h-backward Lagrangian Particle Dispersion simulations is presented for nine aircraft sites measuring vertical profiles of atmospheric CO2 mixing ratios along the 42° N parallel in NE Spain to assess the surface influence at a regional scale (102–103 km) at different altitudes in the vertical profile (600, 1200, 2500 and 4000 meters above the sea level, m a.s.l.). The Potential Surface Influence (PSI) area for the 96-h-backward simulations, defined as the air layer above ground with a thickness of 300 m, are reduced from the continental scale (~107 km2) to the watershed one (~104 km2), when a Residence Time Threshold Criteria (Rttc) greater than 500 s is imposed for each grid cell. In addition, this regional restricted information is confined during 50 h before the arrival for simulations centered at 600 and 1200 m a.s.l. At higher altitudes (2500 and 4000 m a.s.l.), the regional surface influence is only recovered during spring and summer months. For simulations centered at 600 and 1200 m a.s.l. sites separated by ~60 km may overlap 20–50% of the regional surface influences whereas sites separated by ~350 km as such do not overlap. The overlap for sites separated by ~60 km decreases to 8–40% at higher altitudes (2500 and 4000 m a.s.l.). A dense network of sampling sites below 2200 m a.s.l. (whether aircraft sites or tall tower ones) guarantees an appropriate regional coverage to properly assess the dynamics of the regional carbon cycle at a watershed scale (102–103 km length scale).

Style APA, Harvard, Vancouver, ISO itp.

40

Vilà-Guerau de Arellano, Jordi, Patrizia Ney, Oscar Hartogensis, Hugo de Boer, Kevin van Diepen, Dzhaner Emin, Geiske de Groot i in. "CloudRoots: integration of advanced instrumental techniques and process modelling of sub-hourly and sub-kilometre land–atmosphere interactions". Biogeosciences 17, nr 17 (31.08.2020): 4375–404. http://dx.doi.org/10.5194/bg-17-4375-2020.

Pełny tekst źródła

Streszczenie:

Abstract. The CloudRoots field experiment was designed to obtain a comprehensive observational dataset that includes soil, plant, and atmospheric variables to investigate the interaction between a heterogeneous land surface and its overlying atmospheric boundary layer at the sub-hourly and sub-kilometre scale. Our findings demonstrate the need to include measurements at leaf level to better understand the relations between stomatal aperture and evapotranspiration (ET) during the growing season at the diurnal scale. Based on these observations, we obtain accurate parameters for the mechanistic representation of photosynthesis and stomatal aperture. Once the new parameters are implemented, the model reproduces the stomatal leaf conductance and the leaf-level photosynthesis satisfactorily. At the canopy scale, we find a consistent diurnal pattern on the contributions of plant transpiration and soil evaporation using different measurement techniques. From highly resolved vertical profile measurements of carbon dioxide (CO2) and other state variables, we infer a profile of the CO2 assimilation in the canopy with non-linear variations with height. Observations taken with a laser scintillometer allow us to quantify the non-steadiness of the surface turbulent fluxes during the rapid changes driven by perturbation of photosynthetically active radiation by cloud flecks. More specifically, we find 2 min delays between the cloud radiation perturbation and ET. To study the relevance of advection and surface heterogeneity for the land–atmosphere interaction, we employ a coupled surface–atmospheric conceptual model that integrates the surface and upper-air observations made at different scales from leaf to the landscape. At the landscape scale, we calculate a composite sensible heat flux by weighting measured fluxes with two different land use categories, which is consistent with the diurnal evolution of the boundary layer depth. Using sun-induced fluorescence measurements, we also quantify the spatial variability of ET and find large variations at the sub-kilometre scale around the CloudRoots site. Our study shows that throughout the entire growing season, the wide variations in stomatal opening and photosynthesis lead to large diurnal variations of plant transpiration at the leaf, plant, canopy, and landscape scales. Integrating different advanced instrumental techniques with modelling also enables us to determine variations of ET that depend on the scale where the measurement were taken and on the plant growing stage.

Style APA, Harvard, Vancouver, ISO itp.

41

Taj, S., A. Rosu-Finsen i M. R. S. McCoustra. "Impact of surface heterogeneity on IR line profiles of adsorbed carbon monoxide on models of interstellar grain surfaces". Monthly Notices of the Royal Astronomical Society 504, nr 4 (22.05.2021): 5806–12. http://dx.doi.org/10.1093/mnras/stab1174.

Pełny tekst źródła

Streszczenie:

ABSTRACT Surface heterogeneity of model amorphous silica films used as a model for interstellar grain surfaces is revealed through the application of the pre-exponential optimized inversion method to previously reported sub-monolayer thermal desorption studies of carbon monoxide (CO) desorption. The impact of that surface heterogeneity, as represented by the coverage dependence of the CO activation energy for desorption from the amorphous silica surface, on the IR spectroscopy of the CO stretching vibration is explored through vibrational line profile synthesis. Comparison is then made to previous investigations of CO line profiles on this surface and on amorphous solid water as reported in Taj et al. (2017, 2019a). A tentative conclusion is drawn that CO vibrationally promoted desorption from, and diffusion on, the amorphous silica surface may be responsible for the correspondingly short vibrational excited state lifetime of CO on that surface. The contrast with CO on amorphous solid water, where direct and rapid vibrational relaxation into the solid water phonon bath occurs, is highlighted. The consequences of this from the standpoint of CO deposition on grain surfaces are discussed.

Style APA, Harvard, Vancouver, ISO itp.

42

Marthews, T. R., C. A. Quesada, D. R. Galbraith, Y. Malhi, C. E. Mullins, M. G. Hodnett i I. Dharssi. "High-resolution hydraulic parameter maps for surface soils in tropical South America". Geoscientific Model Development 7, nr 3 (6.05.2014): 711–23. http://dx.doi.org/10.5194/gmd-7-711-2014.

Pełny tekst źródła

Streszczenie:

Abstract. Modern land surface model simulations capture soil profile water movement through the use of soil hydraulics sub-models, but good hydraulic parameterisations are often lacking, especially in the tropics. We present much-improved gridded data sets of hydraulic parameters for surface soil for the critical area of tropical South America, describing soil profile water movement across the region to 30 cm depth. Optimal hydraulic parameter values are given for the Brooks and Corey, Campbell, van Genuchten–Mualem and van Genuchten–Burdine soil hydraulic models, which are widely used hydraulic sub-models in land surface models. This has been possible through interpolating soil measurements from several sources through the SOTERLAC soil and terrain data base and using the most recent pedotransfer functions (PTFs) derived for South American soils. All soil parameter data layers are provided at 15 arcsec resolution and available for download, this being 20x higher resolution than the best comparable parameter maps available to date. Specific examples are given of the use of PTFs and the importance highlighted of using PTFs that have been locally parameterised and that are not just based on soil texture. We discuss current developments in soil hydraulic modelling and how high-resolution parameter maps such as these can improve the simulation of vegetation development and productivity in land surface models.

Style APA, Harvard, Vancouver, ISO itp.

43

Yeum, Soran, i MyoungSo Kim. "Latent profile analysis ofemotional labor strategies in subordinate roles". Korean Journal of Industrial and Organizational Psychology 30, nr 3 (31.08.2017): 465–89. http://dx.doi.org/10.24230/kjiop.v30i3.465-489.

Pełny tekst źródła

Streszczenie:

The purpose of this study was to (1) confirm how employees utilize each regulation strategy of emotional labor(surface and deep acting) based on person-centered approach and (2) to examine determinants for each profile and the relationship between each profile and job effectiveness. A total of 507 employees working in a variety of different fields in Korea participated in an on-line survey. To identify sub-populations of emotional labor strategies in subordinate roles, latent profile analysis was adopted. The results indicated that five groups(surface actors, deep actors, non actors, low actors, regulators) were classified. In addition, each group was significantly distinguished by the antecedents of social stressor and leader trust, also related to various outcome variables(i.e., burn-out, job engagement, turn-over intention, felt-inauthenticity). These results showed how variables operate within people and shed light on variable-centered approach ignoring the possibility of distinct combinations of emotional regulation strategies. On the basis of the results, the implications and future research directions were discussed.

Style APA, Harvard, Vancouver, ISO itp.

44

Lima, Erivaldo Genuíno, Fabiana Medeiros Nascimento Silva, Tellys Lins Almeida Barbosa i Meiry Gláucia Freire Rodrigues. "Organic Structure-Directing Agent Free Synthesis of Mordenite with Seeds, Used as A Support for Mo Catalysts in the Transesterification of Soybean Oil". Catalysis Research 03, nr 02 (7.04.2023): 1–20. http://dx.doi.org/10.21926/cr.2302015.

Pełny tekst źródła

Streszczenie:

This work prepared mordenite using seeds and without organic structure-directing agents (OSDAs). The Mo/Mordenite was prepared through wet impregnation and the catalysts’ performance was checked for transesterification of soybean oil with methanol. The mordenite zeolite was prepared through hydrothermal crystallization under static conditions with a molar composition of 6Na2O:Al2O3:30SiO2:780H2O. The catalyst samples were characterized crystallinity through X-ray diffraction, elemental composition by X-ray fluorescence spectroscopy, Surface areas by N2 adsorption-desorption, surface morphology scanning electron microscopy, functional group by infrared spectroscopy and active sites by temperature programmed desorption of ammonia. The transesterification of soybean oil was carried out using the following parameters: 5% catalyst by weight, 1:12 oil to methanol molar ratio, at 200°C for either 12 h or 24 h. X-ray diffraction patterns showed the characteristic peaks of the mordenite structure. After molybdenum oxide was added, the structure of mordenite zeolite was conserved while the specific surface area was reduced. The morphology can be described as a highly crystalline material with well-defined crystalline particles having a spherical profile characteristic of the typical morphology of sodium mordenite zeolite with a low silicon/aluminum ratio. The catalyst samples exhibited sites of a weak and medium-strength nature. The higher activity of the catalyst (Mo/Mordenite) about mordenite zeolite, could be justified by the existence of molybdenum. The wet impregnation of metal (Mo) on the surface of the MOR zeolite is an effective option to increase the acidity of the solid catalysts. Mordenite with 8.84% Mo could be a promising catalyst for the biodiesel factory.

Style APA, Harvard, Vancouver, ISO itp.

45

Thiel, David V. "A Preliminary Assessment of Glacial Ice Profiling Using Vlf Surface-Impedance Measurements". Journal of Glaciology 32, nr 112 (1986): 376–82. http://dx.doi.org/10.1017/s0022143000012077.

Pełny tekst źródła

Streszczenie:

AbstractVLF surface-impedance measurements have been used in the past for sub-surface mapping. The application of this technique to glacial ice probing is discussed theoretically and results of measurements on Brewster Glacier, New Zealand, are presented. Results were fitted to a three-layer model and a section profile is given. Dramatic changes in the phase of the surface impedance were observed in the vicinity of crevasses. Results indicate that the technique has potential as a tool for quick, reliable, and non-invasive ice-thickness measurements.

Style APA, Harvard, Vancouver, ISO itp.

46

Thiel, David V. "A Preliminary Assessment of Glacial Ice Profiling Using Vlf Surface-Impedance Measurements". Journal of Glaciology 32, nr 112 (1986): 376–82. http://dx.doi.org/10.3189/s0022143000012077.

Pełny tekst źródła

Streszczenie:

AbstractVLF surface-impedance measurements have been used in the past for sub-surface mapping. The application of this technique to glacial ice probing is discussed theoretically and results of measurements on Brewster Glacier, New Zealand, are presented. Results were fitted to a three-layer model and a section profile is given. Dramatic changes in the phase of the surface impedance were observed in the vicinity of crevasses. Results indicate that the technique has potential as a tool for quick, reliable, and non-invasive ice-thickness measurements.

Style APA, Harvard, Vancouver, ISO itp.

47

Paradkar, B. S., S. M. Chitre i V. Krishan. "Mean field solar surface dynamo in the presence of partially ionized plasmas and sub-surface shear layer". Monthly Notices of the Royal Astronomical Society 488, nr 3 (25.07.2019): 4329–37. http://dx.doi.org/10.1093/mnras/stz2008.

Pełny tekst źródła

Streszczenie:

Abstract A non-linear α − Ω dynamo in the partially ionized turbulent plasma in the presence of sub-surface velocity shear is studied with mean-field electrodynamics. Such a dynamo is probably operational in the near-surface region of the Sun, where the presence of both neutrals and the velocity shear (due to sub-surface shear layer in the rotation profile) is observationally well established. In particular, we show that the inclusion of ambipolar diffusion leads to a saturation of magnetic field amplitudes in the α − Ω dynamo. We also demonstrate that the temporal evolution of large-scale global magnetic fields follows the well-known pattern similar to the ‘butterfly’ diagram displayed by sunspots. As usual the velocity shear converts part of the poloidal into the toroidal magnetic field which in turn is regenerated largely by the combined kinetic plus Hall helicity, thus closing the dynamo loop. In addition, by allowing temporal variation in the helicity and ambipolar diffusion coefficient we are able to reproduce the grand-minimum type behaviour of the solar dynamo. Details of theoretical model along with numerical computations of dynamo equations in the partially ionized plasma are outlined. The solar surface dynamo model envisaged in this work could operate in conjunction with the global dynamo present in the bulk of the convection zone.

Style APA, Harvard, Vancouver, ISO itp.

48

Moges, Kidist, Mitsuru Sometani, Takuji Hosoi, Takayoshi Shimura, Shinsuke Harada i Heiji Watanabe. "Sub-nm-Scale Depth Profiling of Nitrogen in NO- and N₂-Annealed SiO₂/4H-SiC(0001) Structures". Materials Science Forum 963 (lipiec 2019): 226–29. http://dx.doi.org/10.4028/www.scientific.net/msf.963.226.

Pełny tekst źródła

Streszczenie:

We demonstrated an x-ray photoelectron spectroscopy (XPS)-based technique to reveal the detailed nitrogen profile in nitrided SiO2/4H-SiC structures with sub-nanometer-scale-resolution. In this work, nitric oxide (NO)- and pure nitrogen (N2)-annealed SiO2/4H-SiC(0001) structures were characterized. The measured results of NO-annealed samples with various annealing duration indicate that preferential nitridation just at the SiO2/SiC interfaces (~0.3 nm) proceeds in the initial stage of NO annealing and a longer duration leads to the distribution of nitrogen in the bulk SiO2 within few nanometers of the interface. The high-temperature N2 annealing was found to induce not only SiO2/SiC interface nitridation similarly to NO annealing but also SiO2 surface nitridation.

Style APA, Harvard, Vancouver, ISO itp.

49

Kaneko, Arata, Hayato Kobayashi i Nobuyuki Moronuki. "Surface Micro-Structuring Using Polymer Elongation". Key Engineering Materials 447-448 (wrzesień 2010): 685–89. http://dx.doi.org/10.4028/www.scientific.net/kem.447-448.685.

Pełny tekst źródła

Streszczenie:

High-aspect structures are fabricated by photo-polymer elongation using a template. The template, tungsten wire of sub-mm diameter, makes SU-8 film locally stretched and deformed in long and fine fibrous geometry. The aspect ratio of fabricated structure becomes over 8, while the finest diameter is less than 10μm. Both of surface tension and viscosity of SU-8 film determines the yield of fibrous micro-structure. The wire diameter and drawing distance allow one to obtain desired profile of structure. Fibrous structures can be hexagonally aligned utilizing appropriate template with specific diameter and pitch of wire designed based on an analysis of surface energy.

Style APA, Harvard, Vancouver, ISO itp.

50

Radjenović, Branislav, i Marija Radmilović-Radjenović. "The Implementation of the Surface Charging Effects in Three-Dimensional Simulations of SiO2 Etching Profile Evolution". Engineering 06, nr 01 (2014): 1–6. http://dx.doi.org/10.4236/eng.2014.61001.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

Artykuły w czasopismach na temat „Sub-surface profile”

Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych