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AN IMPLICIT ALGORITHM OF THIN LAYER EQUATIONS IN VISCOUS,TRANSONIC,TWO-PHASE NOZZLE FLOW
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作者 何洪庆 侯晓 +1 位作者 蔡体敏 吴心平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第4期323-334,共12页
Omitting viscosity along flow direction, we have simplified the dimensionless N-Sequations in arbitrary curved coordinate system as the thin layer equations. Using theimplicit approximate-factorization algorithm to so... Omitting viscosity along flow direction, we have simplified the dimensionless N-Sequations in arbitrary curved coordinate system as the thin layer equations. Using theimplicit approximate-factorization algorithm to solve the gas-phase governing equ-ations and the characteristic method to follow the tracks of particles, we then obtainedthe full coupled numerical method of two-phase.transonic, turbulent flow. Here, par- ticle size may be grouped, the subsonic boundary condition at entry of nozzle is ireatedby quasi-characteristic method in reference plane and the algebraic model is used forturbulent flow. These methods are applied in viscous two-phase flow. calculation of ro-cket nozzle and in the prediciton of thrust and specific impulse for solid propellant ro-cket motor. The calculation results are in good agreement with the measurerment va-lues. Moreover, the influences of different particle radius, different particle mass frac-tion and particle size grouped on flow field have been discussed, and the influences of particle two-dimensional radial velosity component and viscosity on specific impulse ofrocket motor have been analysed.The method of this paper possesses the advantage of saving computer time. More important, the effect is more obvious for the calculation of particle size being grouped. 展开更多
关键词 thin layer equations two-phase viscous transonic nozzle flow implicit algorithm
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Quantum dynamics within curved thin layers with deviation
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作者 程润 赵浩 +4 位作者 罗翠柏 周璇 王必利 李延标 王骏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期502-507,共6页
Combining the deviation between thin layers' adjacent surfaces with the confining potential method applied to the quantum curved systems,we derive the effective Schr?dinger equation describing the particle constra... Combining the deviation between thin layers' adjacent surfaces with the confining potential method applied to the quantum curved systems,we derive the effective Schr?dinger equation describing the particle constrained within a curved layer,accompanied by a general geometric potential V_(gq) composed of a compression-corrected geometric potential V_(gq)~*and a novel potential V_(gq)~(**) brought by the deviation.Applying this analysis to the cylindrical layer emerges two types of deviation-induced geometric potential,resulting from the the cases of slant deviation and tangent deviation,respectively,which strongly renormalizes the purely geometric potential and contribute to the energy spectrum based on a very substantial deepening of bound states they offer. 展开更多
关键词 confining potential method quantum mechanics curved thin layer
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Thin Layer Identification of Jiedu Shengxue Granules and Determination of Notoginsenoside R1 Content
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作者 Zhenying FU Bing QING +6 位作者 Yinghong HUANG Xianyi SHI Meiyan QIU Xian PENG Jiangcun WEI Fengzhen LI Wen ZHONG 《Medicinal Plant》 2024年第1期71-74,共4页
[Objectives]To establish the quality standard of hospital preparation Jiedu Shengxue granules.[Methods]Scleromitrion diffusum and Prunella vulgaris in Jiedu Shengxue granules were qualitatively identified by thin laye... [Objectives]To establish the quality standard of hospital preparation Jiedu Shengxue granules.[Methods]Scleromitrion diffusum and Prunella vulgaris in Jiedu Shengxue granules were qualitatively identified by thin layer chromatography(TLC).A high performance liquid chromatography(HPLC)was established to determine the content of notoginsenoside R1 in the granule.[Results]The traditional Chinese medicinal materials in Jiedu Shengxue granules could be identified by TLC,and the characteristic spots were stable and clear.Notoginsenoside R1 had a good linear relationship in the range of 10.45-104.5μg/mL,with an average recovery of 98.52%and RSD=2.36%.[Conclusions]TLC and HPLC,as the quality control methods of Jiedu Shengxue granules,have high accuracy and good repeatability,which lays a foundation for the quality control of this mixture. 展开更多
关键词 Jiedu Shengxue granules thin layer identification Notoginsenoside R1 Quality standard
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Determination of Natural Logarithm of Diffusion Coefficient and Activation Energy of Thin Layer Drying Process of Ginger Rhizome Slices
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作者 Austin Ikechukwu Gbasouzor Sam Nna Omenyi +1 位作者 Sabuj Mallik Jude E. Njoku 《World Journal of Engineering and Technology》 2024年第1期213-228,共16页
This study is an extension of the previous work done with ARS-680 Environmental Chamber. Drying is a complex operation that demands much energy and time. Drying is essentially important for preservation of ginger rhiz... This study is an extension of the previous work done with ARS-680 Environmental Chamber. Drying is a complex operation that demands much energy and time. Drying is essentially important for preservation of ginger rhizome. Drying of ginger was modeled, and then the effective diffusion coefficient and activation energy were determined. For this purpose, the experiments were done at six levels of varied temperatures: 10°C, 20°C, 30°C, 40°C, 50°C and 60°C. The values of effective diffusion coefficients obtained in this work for the variously treated ginger rhizomes closely agreed with the average effective diffusion coefficients of other notable authors who determined the drying kinetics and convective heat transfer coefficients of ginger slices. 展开更多
关键词 Activation Energy Diffusion Coefficients Ginger Rhizomes Drying Model Drying Time Moisture Ratio thin layer
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Numerical Study and Optimization of CZTS-Based Thin-Film Solar Cell Structure with Different Novel Buffer-Layer Materials Using SCAPS-1D Software
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作者 Md. Zamil Sultan Arman Shahriar +4 位作者 Rony Tota Md. Nuralam Howlader Hasibul Haque Rodro Mahfuja Jannat Akhy Md. Abir Al Rashik 《Energy and Power Engineering》 2024年第4期179-195,共17页
This study explored the performances of CZTS-based thin-film solar cell with three novel buffer layer materials ZnS, CdS, and CdZnS, as well as with variation in thickness of buffer and absorber-layer, doping concentr... This study explored the performances of CZTS-based thin-film solar cell with three novel buffer layer materials ZnS, CdS, and CdZnS, as well as with variation in thickness of buffer and absorber-layer, doping concentrations of absorber-layer material and operating temperature. Our aims focused to identify the most optimal thin-film solar cell structure that offers high efficiency and lower toxicity which are desirable for sustainable and eco-friendly energy sources globally. SCAPS-1D, widely used software for modeling and simulating solar cells, has been used and solar cell fundamental performance parameters such as open-circuited voltage (), short-circuited current density (), fill-factor() and efficiency() have been optimized in this study. Based on our simulation results, it was found that CZTS solar cell with Cd<sub>0.4</sub>Zn<sub>0.6</sub>S as buffer-layer offers the most optimal combination of high efficiency and lower toxicity in comparison to other structure investigated in our study. Although the efficiency of Cd<sub>0.4</sub>Zn<sub>0.6</sub>S, ZnS and CdS are comparable, Cd<sub>0.4</sub>Zn<sub>0.6</sub>S is preferable to use as buffer-layer for its non-toxic property. In addition, evaluation of performance as a function of buffer-layer thickness for Cd<sub>0.4</sub>Zn<sub>0.6</sub>S, ZnS and CdS showed that optimum buffer-layer thickness for Cd<sub>0.4</sub>Zn<sub>0.6</sub>S was in the range from 50 to 150nm while ZnS offered only 50 – 75 nm. Furthermore, the temperature dependence performance parameters evaluation revealed that it is better to operate solar cell at temperature 290K for stable operation with optimum performances. This study would provide valuable insights into design and optimization of nanotechnology-based solar energy technology for minimizing global energy crisis and developing eco-friendly energy sources sustainable and simultaneously. 展开更多
关键词 thin-Film Solar Cell CZTS Buffer-layer Renewable Energy Green-House Gases Efficiency
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Preparation Process and Thin Layer Chromatography Identification of Wufang Babu Poultice
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作者 Junjun LIU Luyao XIE +2 位作者 Chuhui ZHOU Zhengteng YANG Xiongbin GUI 《Medicinal Plant》 CAS 2023年第4期58-61,共4页
[Objectives] To establish the process flow of preparation of Wufang Babu Poultice and the identification method of thin layer chromatography (TLC). [Methods] For the forming process of Wufang Babu Poultice, the prepar... [Objectives] To establish the process flow of preparation of Wufang Babu Poultice and the identification method of thin layer chromatography (TLC). [Methods] For the forming process of Wufang Babu Poultice, the preparation method of mixed pharmaceutical powder with suitable pharmaceutical excipients was adopted. Qualitative identification of medicinal materials in Wufang Babu Poultice (Strychni Semen, Rhei Radix Et Rhizoma, Dipsaci Radix, and Angelicae Sinensis Radix) was carried out by TLC. [Results] Mixed pharmaceutical powder mixed with glycerol, gelatin and other pharmaceutical excipients can be prepared for forming. The test solution chromatography of each medicinal material (Strychni Semen, Rhei Radix et Rhizoma, Dipsaci Radix, Angelicae Sinensis Radix) showed pigment spots of the same color at the same position as its corresponding control medicinal materials and reference chromatography, and the display was clear. [Conclusions] The preparation process is simple and feasible, and can be used as the forming process of Wufang Babu Poultice. The TLC determination method is simple to operate, has good specificity, and has no effect on negative results, and can be used for identification of Wufang Babu Poultice. 展开更多
关键词 Wufang Babu Poultice Preparation process thin layer chromatography(TLC)
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Application of the Adaptive Shrinkage Genetic Algorithm in the Feasible Region to TEM Conductive Thin Layer Inversion 被引量:14
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作者 李貅 薛国强 +3 位作者 宋建平 郭文波 武军杰 沈梅芳 《Applied Geophysics》 SCIE CSCD 2005年第4期204-210,共7页
Combining the adaptive shrinkage genetic algorithm in the feasible region with the imaging of apparent vertical conductance differential, we have inverted the TEM conductive thin layer. The result of the inversion dem... Combining the adaptive shrinkage genetic algorithm in the feasible region with the imaging of apparent vertical conductance differential, we have inverted the TEM conductive thin layer. The result of the inversion demonstrates that by adaptive shrinkage in the feasible region, the calculation speed accelerates and the calculation precision improves. To a certain extent, in this method we surmount the transient electromagnetic sounding equivalence and reduced equivalence scope. Comparison of the inverted result with the forward curve clearly shows that we can image the conductive thin layer. 展开更多
关键词 transient electromagnetic method genetic algorithm INVERSION apparent longitudinal conductance and conductive thin layer.
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Early Stage Hydration Mechanism of Cellulose Ether Modified Thin Layer Cement Pastes 被引量:7
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作者 马保国 SU Lei +1 位作者 JIAN Shouwei SONG Xuefeng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第6期1172-1176,共5页
The early stage hydration mechanism of cellulose ether modified thin layer cement pastes was studied, using brick as the matrix. Samples of 6 h, 24 h, and 3 d and 7 d hydration time were analyzed to study the hydratio... The early stage hydration mechanism of cellulose ether modified thin layer cement pastes was studied, using brick as the matrix. Samples of 6 h, 24 h, and 3 d and 7 d hydration time were analyzed to study the hydration law on the surface of high water-absorbing matrix. Hydration products were qualitatively and semi-quantitatively analyzed using XRD, TG-DSC-DTG, FTIR and SEM. The experimental results show that there is no enough water for 2 mm thick cement pastes to hydrate, because of rapid water absorption of matrix. Trace amounts of Ca (OH)2 was detected after three days hydration. With the prolongation of hydration time, the category and concentration of hydration products do not change. Compared with 2 mm thick cement pastes, 6 mm thick cement pastes and 10 mm thick cement pastes have lower dehydration rate and water loss. The humidity field of the cement paste show different changes within the same time. 6 mm thick cement paste and 10 mm thick cement pastes have longer time and more water to hydrate. Ca(OH)2 and ettringite were detected after 6 hours hydration and the concentrations of hydration products increased from 24 hours to 7 days. 展开更多
关键词 cellulose ether thin layer cement pastes high water-absorbing matrix hydration products
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Measurement of Attenuation of Ultrasonic Propagating through the Thin Layer Media with Time Delay Spectrum 被引量:3
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作者 WANG Xingguo CHANG Junjie +3 位作者 SHAN Yingchun TIE Shaodong YAO Man XU Jiujun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第1期129-134,共6页
The ultrasonic attenuation coefficient is one of the most important acoustic parameters to character the performance of a thin layer media, but it can not be measured due to mutual superposition of multiple reflected ... The ultrasonic attenuation coefficient is one of the most important acoustic parameters to character the performance of a thin layer media, but it can not be measured due to mutual superposition of multiple reflected waves at the same interface in ultrasonic testing. Ultrasonic pulse echo and lamb wave to evaluate the thin layer media can not obtain attenuation coefficient at present. In this paper, analytical method was used to study the acoustics characteristic of thin layer media with the ultrasonic echo testing. Meanwhile, the process of ultrasonic attenuation measurement was presented. Simulation and experimental investigation is focused on a thin layer of rubber. Attenuation coefficient was introduced and evaluation mathematics model was established by the two echoes cross-correlation with and without the thin layer media based on the time delay spectrum. It involved the parameters related to the acoustic properties of the thin layer media. Through calculating the sound velocity and acoustic impedance with the evaluation model, it can deduce the relation between the attenuation coefficient and the frequency. Through analyzing the simulation results, it indicated that the attenuation coefficients were invariable with the varying of the frequency. However, the attenuation coefficients increased with the frequency increasing by ultrasonic testing the thin layer of rubber. The reason was that the attenuation factor was not taken into account during the simulation. This method overcomes shortcomings that the traditional ultrasonic testing can not evaluate the thin layer media whose thickness is less than motivation wavelength. It is a new solution to study the attenuation characteristic and on-line nondestructive evaluation in the thin layer media. 展开更多
关键词 ultrasonic testing the thin layer media time delay spectrum attenuation coefficient
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Secondary metabolite credentials ofEvolvulus alsinoides by high performance thin layer chromatography(HPTLC) 被引量:2
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作者 Duraisamy Gomathi Manokaran Kalaiselvi +3 位作者 Ganesan Ravikumar Dominic Sophia Velliyur Kanniappan Gopalakrishnan Chandrasekar Uma 《The Journal of Biomedical Research》 CAS 2012年第4期295-302,共8页
Plants and plant-based products are the bases of many modern pharmaceuticals that are current in use today for various diseases.The aim of the study was to investigate the biochemical constituents and high performance... Plants and plant-based products are the bases of many modern pharmaceuticals that are current in use today for various diseases.The aim of the study was to investigate the biochemical constituents and high performance thin layer chromatography(HPTLC) finger printing of the ethanolic extract of Evolvulus alsinoides.Phytochemical screening was done by standard procedures and HPTLC method was also established to analyze alkaloids,flavonoids and phenolic compounds from the ethanolic extract of Evolvulus alsinoides.Preliminary phytochemical screening showed that ethanol extracted more secondary metabolites than other solvents.HPTLC fingerprinting analysis showed the presence of various alkaloids,flavonoids and phenols(quercetin) in the ethanolic extract.It can be concluded that Evolvulus alsinoides may serve as a source of potent antioxidants that may be used in the prevention of various diseases such as cancer,diabetes and cardiovascular diseases due to the presence of phenolic compounds.HPTLC finger print of Evolvulus alsinoides may be useful in the differentiation of the species from adulterants and act as a biochemical marker for this medicinally important plant in the pharmaceutical industry and plant systematic studies. 展开更多
关键词 Evolvulus alsinoides high performance thin layer chromatography(HPTLC) secondary metabolites CONVOLVULACEAE
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Comparison of liquid-liquid extraction-thin layer chromatography with solid-phase extraction-high-performance thin layer chromatography in detection of urinary morphine 被引量:1
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作者 Ali Ahadi Alireza Partoazar +1 位作者 Mohammad Hassan Abedi Khorasgani Seyed Vahid Shetab Boushehri 《The Journal of Biomedical Research》 CAS 2011年第5期362-367,共6页
Liquid-liquid extraction-thin layer chromatography (LLE-TLC) has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction (SPE) is gradually replacing the tr... Liquid-liquid extraction-thin layer chromatography (LLE-TLC) has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction (SPE) is gradually replacing the tra- ditional LLE method. High performance thin layer chromatography (HPTLC) has several advantages over TLC. The present work studied the higher efficiency of a new SPE-HPTLC method over that of a routine LLE-TLC method, in extraction and detection of urinary morphine. Fifty-eight urine samples, primarily identified as mor- phine-positive samples by a strip test, 'were re-screened by LLE-TLC and SPE-HPTLC. The results of LLE-TLC and SPE-HPTLC were then compared with each other. The results showed that the SPE-HPTLC detected 74% of total samples as morphine-positive samples whereas the LLE-TLC detected 48% of the same samples. We further discussed the effect of codeine abuse on TLC analysis of urinary morphine. Regarding the importance of morphine detection in urine, the present combined SPE-HPTLC method is suggested as a replacement method for detection of urinary morphine by many reference laboratories. 展开更多
关键词 morphine detection liquid-liquid extraction thin-layer chromatography solid-phase extraction highperformance thin layer chromatography
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Effect of SDBS on interfacial electron transfer at the liquid/liquid interface by thin layer method 被引量:1
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作者 Xiu Hui Liu Cun Wu Dong Kai Zhang Fu Peng Zhi Zhen Ding Xiao Quan Lu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第9期1115-1118,共4页
The effect of an adsorbed anionic surfactant sodium dodecyl benzene sulfonate (SDBS) on electron transfer (ET) reaction between ferricyanide aqueous solution and decamethylferrocene (DMFc) located on the adjacen... The effect of an adsorbed anionic surfactant sodium dodecyl benzene sulfonate (SDBS) on electron transfer (ET) reaction between ferricyanide aqueous solution and decamethylferrocene (DMFc) located on the adjacent organic phase was investigated for the first time by thin layer method. The adsorption of SDBS at the interface resulted in a decay in the cathodic plateau current of bimolecular reaction with increasing concentrations of SDBS in aqueous phase. However, the rate constant of electron transfer (ket) increased monotonically as the SDBS concentrations increased from 0 to 200 p, moFL. The experimental results showed that SDBS formed patches on the interface and influenced the structure of electrical double layer. 2009 Xiao Quan Lu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 Anionic surfactant Liquid/liquid interface Electron transfer thin layer method
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Increasing analyzable steel thickness for thin layer activation experiments 被引量:1
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作者 Joao Francisco de Oliveira Antunes Mauro Lucio Borges Lemos +2 位作者 Michel de Almeida Franca Julio Cezar Suita Celso Marcelo Franklin Lapa 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第3期35-44,共10页
The thin layer activation technique(TLA)is very effective in wear analysis for tribological systems where disassembly is costly or impractical.Since its development in the 1970s,TLA has been applied through direct irr... The thin layer activation technique(TLA)is very effective in wear analysis for tribological systems where disassembly is costly or impractical.Since its development in the 1970s,TLA has been applied through direct irradiation of solid targets using ionizing particle beams to obtain an activation with a specific profile.This profile is then used to measure wear in a variety of experiments.These experiments rely heavily on how deep the normalized activation occurs.Depths of 30μm to 50μm are obtained for constant activation by the standard method,which for many experiments is sufficient.However,many others would benefit greatly from a 300μm constant activation layer,such as high-performance engines,softer alloys(brakes),and oil transport systems.Achieving this aim was the goal of this paper.First,we needed to find an adequate irradiation line for the TLA technique.Then,another technique/system was developed(the Attenuation Wheel),which would bring the depth of constant activation from 50μm to 300μm. 展开更多
关键词 thin layer activation WEAR Proton beam Attenuation wheel
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Determination of the parameters of a linear-viscoelastic thin layer using the normally-incident ultrasonic waves 被引量:1
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作者 姚桂锦 吕卫国 +3 位作者 宋若龙 崔志文 张香林 王克协 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期350-357,共8页
This paper proposes a method of simultaneous determination of the four layer parameters (mass density, longitudinal velocity, the thickness and attenuation) of an immersed linear-viscoelastic thin layer by using the... This paper proposes a method of simultaneous determination of the four layer parameters (mass density, longitudinal velocity, the thickness and attenuation) of an immersed linear-viscoelastic thin layer by using the normally-incident reflected and transmitted ultrasonic waves. The analytical formula of the layer thickness related to the measured trans- mitted transfer functions is derived. The two determination steps of the four layer parameters are developed, in which acoustic impedance, time-of-flight and attenuation are first determined by the reflected transfer functions. Using the derived formula, it successively calculates and determines the layer thickness, longitudinal velocity and mass density by the measured transmitted transfer functions. According to the two determination steps, a more feasible and simplified measurement setups is described. It is found that only three signals (the reference waves, the reflected and transmitted waves) need to be recorded in the whole measurement for the determination of the four layer parameters. A study of the stability of the determination method against the experimental noises and the error analysis of the four layer parameters are made. This study lays the theoretical foundation of the practical measurement of a linear-viscoelastic thin layer. 展开更多
关键词 ultrasonic determination normally-incident reflected/transmitted waves layer parameters linear-viscoelastic thin layer
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3D Fe-MOF embedded into 2D thin layer carbon nitride to construct 3D/2D S-scheme heterojunction for enhanced photoreduction of CO_(2) 被引量:1
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作者 Xiaoxue Zhao Mengyang Xu +3 位作者 Xianghai Song Weiqiang Zhou Xin Liu Pengwei Huo 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第10期2625-2636,共12页
Regulating charge transfer to achieve specific transfer path can improve electron utilization and complete efficient photoreduction of CO_(2).Here,we fabricated a S-scheme heterojunction of CN/Fe-MOF by an in-situ ass... Regulating charge transfer to achieve specific transfer path can improve electron utilization and complete efficient photoreduction of CO_(2).Here,we fabricated a S-scheme heterojunction of CN/Fe-MOF by an in-situ assembly strategy.The S-scheme charge transfer mechanism was confirmed by band structure,electron spin resonance(ESR)and work function(Φ)analysis.On the one hand,the response of Fe-MOF in the visible region improved the utilization of light energy,thus increasing the ability of CN/Fe-MOF to generate charge carriers.On the other hand,CN,as the active site,not only had strong adsorption capacity for CO_(2),but also retained photogenerated electrons with high reduction capacity because of S-scheme charge transfer mechanism.Hence,in the absence of any sacrificial agent and cocatalyst,the optimized 50CN/Fe-MOF obtained the highest CO yield(19.17μmol g^(–1))under UV-Vis irradiation,which was almost 10 times higher than that of CN.In situ Fourier transform infrared spectra not only revealed that the photoreduction of CO_(2) occurred at the CN,but also demonstrated that the S-scheme charge transfer mechanism enabled 50CN/Fe-MOF to have a stronger ability to generate HCOO–than CN. 展开更多
关键词 thin layer porous g-C_(3)N_(4) S-Scheme heterojunction Photocatalytic CO_(2)reduction Fe-MOF Surface intermediate
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Evaluation of quantitative variation of secondary metabolites in Bergenia ciliata(Haw.)using high performance thin layer chromatography 被引量:1
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作者 Nishi Srivastava Sharad Srivastava +2 位作者 Shikhar Verma Ajay Kumar Singh Rawat Abdul Rahman Khan 《The Journal of Biomedical Research》 CAS 2014年第4期328-331,共4页
Dear Editor: Therapeutically active metabolite contents in a med- icinal plant vary in nature, which may impact on its therapeutic efficacy. Bergenia (Saxifragaceae) is an evergreen perennial herb widely distribut... Dear Editor: Therapeutically active metabolite contents in a med- icinal plant vary in nature, which may impact on its therapeutic efficacy. Bergenia (Saxifragaceae) is an evergreen perennial herb widely distributed in Central and East Asia with about 30 species reported worldwide. It grows at a range of altitudes from the Khasia hills at 400 feet to the temperate Himalayas from Kashmir to Bhutan at 7,000-10,000 feet. Its distribution over a wide range of altitudinal zones makes it a good candidate for studying variations in its metabolic profiles under different climatic conditions. Bergenin (C-glycoside of 4-O-methyl gallic acid) has been identified as a potent active secondary metabolite in Bergenia and other therapeutically active constituents including, among others, gallic acid (3,4,5 trihydroxybenzoic acid), (+) catechin, and gallicin (Fig. 1). 展开更多
关键词 HPTLC using high performance thin layer chromatography Evaluation of quantitative variation of secondary metabolites in Bergenia ciliata Haw HIGH
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Breakdown voltage model and structure realization of a thin silicon layer with linear variable doping on a silicon on insulator high voltage device with multiple step field plates 被引量:2
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作者 乔明 庄翔 +4 位作者 吴丽娟 章文通 温恒娟 张波 李肇基 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第10期504-511,共8页
Based on the theoretical and experimental investigation of a thin silicon layer(TSL) with linear variable doping(LVD) and further research on the TSL LVD with a multiple step field plate(MSFP),a breakdown voltag... Based on the theoretical and experimental investigation of a thin silicon layer(TSL) with linear variable doping(LVD) and further research on the TSL LVD with a multiple step field plate(MSFP),a breakdown voltage(BV) model is proposed and experimentally verified in this paper.With the two-dimensional Poisson equation of the silicon on insulator(SOI) device,the lateral electric field in drift region of the thin silicon layer is assumed to be constant.For the SOI device with LVD in the thin silicon layer,the dependence of the BV on impurity concentration under the drain is investigated by an enhanced dielectric layer field(ENDIF),from which the reduced surface field(RESURF) condition is deduced.The drain in the centre of the device has a good self-isolation effect,but the problem of the high voltage interconnection(HVI) line will become serious.The two step field plates including the source field plate and gate field plate can be adopted to shield the HVI adverse effect on the device.Based on this model,the TSL LVD SOI n-channel lateral double-diffused MOSFET(nLDMOS) with MSFP is realized.The experimental breakdown voltage(BV) and specific on-resistance(R on,sp) of the TSL LVD SOI device are 694 V and 21.3 ·mm 2 with a drift region length of 60 μm,buried oxide layer of 3 μm,and silicon layer of 0.15 μm,respectively. 展开更多
关键词 breakdown voltage model enhanced dielectric layer field thin silicon layer linear variable doping multiple step field plates
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Effect of the thin cell layer technique in the induction of somatic embryos in Pinus patula Schl. et Cham 被引量:1
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作者 Marco A.Ramirez-Mosqueda Lourdes G.Iglesias-Andreu +4 位作者 Arturo A.Armas-Silva Esmeralda J.Cruz-Gutierrez Jose F.de la Torre-Sanchez Otto R.Leyva-Ovalle Carlos M.Galan-Paez 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第4期1535-1539,共5页
Pinus patula is a species commonly used for reforestation in Mexico.However,efficient methods for the mass production seedlings are required.Micropropagation particularly by somatic embryogenesis provides an option fo... Pinus patula is a species commonly used for reforestation in Mexico.However,efficient methods for the mass production seedlings are required.Micropropagation particularly by somatic embryogenesis provides an option for the rapid multiplication of high-quality,genetically improved material.This study induces somatic embryogenesis in this species using the thin cell layer(TCL)technique.Two sources of explants(complete immature embryos;lTCL segments from immature embryos)were evaluated.The efficiency of TCL from longitudinal sections[lTCL]and transverse[tTCL]was evaluated.The results show using thin cell layers from immature embryos cultivated in 16 light/8 dark hours achieves induction of somatic embryos.A higher percentage of embryogenic callus was obtained when tTCL segments were used as an explant source.These results produced somatic embryos from tTCL segments of an immature embryo without germinating the seed,making the process more time efficient.In addition,this technique can be used to generate somatic embryogenesis in forest species that have low germination rates. 展开更多
关键词 Pinus patula Somatic embryos MICROPROPAGATION thin CELL layer Maturation
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Large energy-loss straggling of swift heavy ions in ultra-thin active silicon layers 被引量:2
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作者 张战刚 刘杰 +13 位作者 侯明东 孙友梅 赵发展 刘刚 韩郑生 耿超 刘建德 习凯 段敬来 姚会军 莫丹 罗捷 古松 刘天奇 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期505-511,共7页
Monte Carlo simulations reveal considerable straggling of energy loss by the same ions with the same energy in fully-depleted silicon-on-insulator (FDSOI) devices with ultra-thin sensitive silicon layers down to 2.5... Monte Carlo simulations reveal considerable straggling of energy loss by the same ions with the same energy in fully-depleted silicon-on-insulator (FDSOI) devices with ultra-thin sensitive silicon layers down to 2.5 rim. The absolute straggling of deposited energy decreases with decreasing thickness of the active silicon layer. While the relative straggling increases gradually with decreasing thickness of silicon films and exhibits a sharp rise as the thickness of the silicon film descends below a threshold value of 50 nm, with the dispersion of deposited energy ascending above ~10%. Ion species and energy dependence of the energy-loss straggling are also investigated. For a given beam, the dispersion of deposited energy results in large uncertainty on the actual linear energy transfer (LET) of incident ions, and thus single event effect (SEE) responses, which pose great challenges for traditional error rate prediction methods. 展开更多
关键词 single event effects energy-loss straggling ultra-thin silicon layer Monte Carlo simulation
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Preparation and characterization of Cd_(1-x)Zn_xS buffer layers for thin film solar cells 被引量:3
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作者 Tian-Wei Zhang Cheng-Jun Zhu +1 位作者 Chao-Zheng Wang Jian Li 《Rare Metals》 SCIE EI CAS CSCD 2013年第1期47-51,共5页
Cd1_xZnxS (x = 0, 0.1, 0.2, 0.3, 1.0) thin films have been grown successfully on soda-lime glass substrates by chemical bath deposition technique as a very promising buffer layer material for optoelectronic device a... Cd1_xZnxS (x = 0, 0.1, 0.2, 0.3, 1.0) thin films have been grown successfully on soda-lime glass substrates by chemical bath deposition technique as a very promising buffer layer material for optoelectronic device applications. The composition, structural properties, surface morphol- ogy, and optical properties of Cd~_xZnxS thin films were characterized by energy dispersive analysis of X-ray tech- nique (EDAX), X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-Vis spectrophotometer tech- niques, respectively. The annealed films were observed to possess the deficient sulfur composition. The results of XRD show that the Cdl_xZnxS (x = 0. l) thin film annealed at 450 ~C forms hexagonal (wurtzite) structure with lattice parameters a = 0.408814 nm, c : 0.666059 nm, and its average grain size is 24.9902 nm. The diffraction peaks become strong with the increasing annealing temperatures. The surface of Cdl_~ZnxS (x = 0.1) thin film annealed at 450 ~C is uninterrupted and homogenous as compared to other temperatures. From optical properties, it is observed that the presence of small amount of Zn results in marked changes in the optical band gap of CdS. The band gaps of the Cdl_xZnxS thin films vary from 2.42 to 3.51 eV as composition varies from x = 0.0 to 1.0. 展开更多
关键词 Solar cells Buffer layers ChemicalCdl_xZnxS thin films bath deposition
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