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Discrimination of Transgenic Rice Based on Near Infrared Reflectance Spectroscopy and Partial Least Squares Regression Discriminant Analysis 被引量:7
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作者 ZHANG Long WANG Shan-shan +2 位作者 DING Yan-fei PAN Jia-rong ZHU Cheng 《Rice science》 SCIE CSCD 2015年第5期245-249,共5页
Near infrared reflectance spectroscopy (NIRS), a non-destructive measurement technique, was combined with partial least squares regression discrimiant analysis (PLS-DA) to discriminate the transgenic (TCTP and mi... Near infrared reflectance spectroscopy (NIRS), a non-destructive measurement technique, was combined with partial least squares regression discrimiant analysis (PLS-DA) to discriminate the transgenic (TCTP and mi166) and wild type (Zhonghua 11) rice. Furthermore, rice lines transformed with protein gene (OsTCTP) and regulation gene (Osmi166) were also discriminated by the NIRS method. The performances of PLS-DA in spectral ranges of 4 000-8 000 cm-1 and 4 000-10 000 cm-1 were compared to obtain the optimal spectral range. As a result, the transgenic and wild type rice were distinguished from each other in the range of 4 000-10 000 cm-1, and the correct classification rate was 100.0% in the validation test. The transgenic rice TCTP and mi166 were also distinguished from each other in the range of 4 000-10 000 cm-1, and the correct classification rate was also 100.0%. In conclusion, NIRS combined with PLS-DA can be used for the discrimination of transgenic rice. 展开更多
关键词 near infrared reflectance spectroscopy genetically-modified food regulation gene protein gene partial least squares regression discrimiant analysis
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Determination of Protein and Starch Content in Whole Maize Kernel by Near Infrared Reflectance Spectroscopy 被引量:2
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作者 WEILiang-ming YANYan-lu DAIJing-rui 《Agricultural Sciences in China》 CAS CSCD 2004年第7期490-495,共6页
Using 128 bulk-kernel samples of inbred lines and hybrids, a study was conducted toinvestigate the feasibility and method of measuring protein and starch contents inintact seeds of maize by near infrared reflectance s... Using 128 bulk-kernel samples of inbred lines and hybrids, a study was conducted toinvestigate the feasibility and method of measuring protein and starch contents inintact seeds of maize by near infrared reflectance spectroscopy (NIRS). The chemometricalgorithms of partial least square (PLS) regression was used. The results indicated thatthe calibration models developed by the spectral data pretreatment of firstderivative+multivariate scattering correction within the spectral region of 10000-4000cm-1, and first derivative + straight line subtraction in 9000-4000cm-1 were thebest for protein and starch, respectively. All these models yielded coefficients ofdetermination of calibration (R2cal) above 0.97, while R2cv and R2val of cross and externalvalidation ranged from 0.92 to 0.95, respectively; however, the root of mean squareerrors of calibration, cross and external validation (RMSEE, RMSECV and RMSEP) werebelow 1(ranged 0.3-0.7),respectively. This study demonstrated that it is feasible touse NIRS as a rapid, accurate, and none-destructive technique to predict protein andstarch contents of whole kernel in the maize quality improvement program. 展开更多
关键词 MAIZE Near infrared reflectance spectroscopy (NIRS) Protein and starch CALIBRATION model
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Characterization of 4H-SiC substrates and epilayers by Fourier transform infrared reflectance spectroscopy
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作者 董林 孙国胜 +7 位作者 郑柳 刘兴昉 张峰 闫果果 赵万顺 王雷 李锡光 王占国 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第4期548-554,共7页
The infrared reflectance spectra of both 4H SiC substrates and epilayers are measured in a wave number range from 400 cm 1 to 4000 cm-1 using a Fourier-transform spectrometer. The thicknesses of the 4H-SiC epilayers a... The infrared reflectance spectra of both 4H SiC substrates and epilayers are measured in a wave number range from 400 cm 1 to 4000 cm-1 using a Fourier-transform spectrometer. The thicknesses of the 4H-SiC epilayers and the electrical properties, including the free-carrier concentrations and the mobilities of both the 4H SiC substrates and the epilayers, are characterized through full line-shape fitting analyses. The correlations of the theoretical spectral profiles with the 4H-SiC electrical properties in the 30 cm-1-4000 cm 1 and 400 cm-1-4000 cm-1 spectral regions are established by introducing a parameter defined as error quadratic sum. It is indicated that their correlations become stronger at a higher carrier concentration and in a wider spectral region (30 cm-1-4000 cm-1). These results suggest that the infrared reflectance technique can be used to accurately determine the thicknesses of the epilayers and the carrier concentrations, and the mobilities of both lightly and heavily doped 4H-SiC wafers. 展开更多
关键词 4H SiC infrared reflectance epilayer thickness electrical properties
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Process Characterization of the Transesterification of Rapeseed Oil to Biodiesel Using Design of Experiments and Infrared Spectroscopy
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作者 Tobias Drieschner Andreas Kandelbauer +1 位作者 Bernd Hitzmann Karsten Rebner 《Journal of Renewable Materials》 SCIE EI 2023年第4期1643-1660,共18页
For optimization of production processes and product quality,often knowledge of the factors influencing the process outcome is compulsory.Thus,process analytical technology(PAT)that allows deeper insight into the proc... For optimization of production processes and product quality,often knowledge of the factors influencing the process outcome is compulsory.Thus,process analytical technology(PAT)that allows deeper insight into the process and results in a mathematical description of the process behavior as a simple function based on the most important process factors can help to achieve higher production efficiency and quality.The present study aims at characterizing a well-known industrial process,the transesterification reaction of rapeseed oil with methanol to produce fatty acid methyl esters(FAME)for usage as biodiesel in a continuous micro reactor set-up.To this end,a design of experiment approach is applied,where the effects of two process factors,the molar ratio and the total flow rate of the reactants,are investigated.The optimized process target response is the FAME mass fraction in the purified nonpolar phase of the product as a measure of reaction yield.The quantification is performed using attenuated total reflection infrared spectroscopy in combination with partial least squares regression.The data retrieved during the conduction of the DoE experimental plan were used for statistical analysis.A non-linear model indicating a synergistic interaction between the studied factors describes the reactor behavior with a high coefficient of determination(R^(2))of 0.9608.Thus,we applied a PAT approach to generate further insight into this established industrial process. 展开更多
关键词 Process analytical technology TRANSESTERIFICATION design of experiment attenuated total reflection infrared spectroscopy partial least square regression
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Improved Visible Transparency of SiO_2/ZnO:Al/CeO_2-TiO_2/SiO_2 Multilayer Films with High UV Absorption and Infrared Reflection Rate 被引量:1
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作者 倪佳苗 赵修建 +1 位作者 ZHAO Qingnan ZHENG Mindong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第5期941-946,共6页
New visible transparent, UV absorption, and high infrared reflection properties have been realized by depositing multilayer Si O2/Zn O: Al/Ce O2-Ti O2/Si O2 films onto glass substrates at low temperature by radio freq... New visible transparent, UV absorption, and high infrared reflection properties have been realized by depositing multilayer Si O2/Zn O: Al/Ce O2-Ti O2/Si O2 films onto glass substrates at low temperature by radio frequency magnetron sputtering. Optimum thickness of Si O2, Zn O: Al(ZAO) and Ce O2-Ti O2(CTO) films were designed with the aid of thin film design software. The degree of antireflection can be controlled by adjusting the thickness and refractive index. The outer Si O2 film can diminish the interference coloring and increase the transparency; the inner Si O2 film improves the adhesion of the coating on the glass substrate and prevents Ca2+, Na+ in the glass substrate from entering the ZAO film. The average transmittance in the visible light range increases by nearly 18%-20%, as compared to double layer ZAO/CTO films. And the films display high infrared reflection rate of above 75% in the wavelength range of 10-25 μm and good UV absorption(> 98%) properties. These systems are easy to produce on a large scale at low cost and exhibit high mechanical and chemical durability. The triple functional films with high UV absorption, antireflective and high infrared reflection rate will adapt to application in flat panel display and architectural coating glass, automotive glass, with diminishing light pollution as well as decreasing eye fatigue and increasing comfort. 展开更多
关键词 Si O2/Zn O:Al /Ce O2-Ti O2/Si O2 TRANSPARENCY high infrared reflection rate ultraviolet absorption optimization
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Temperature-dependent far-infrared properties of Bi_(12)GeO_(20) single crystal
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作者 Muhammad Kamran 戴耀民 +5 位作者 马继云 李博宏 何世坤 张伟君 郑小睿 邱祥冈 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第10期4425-4429,共5页
Fax-infraxed reflectivity spectra of bismuth germanium oxide (Bi12GeO20) single crystals are measured from room temperature down to 10 K. All the reflectivity spectra are fitted to a complex dielectric function ε... Fax-infraxed reflectivity spectra of bismuth germanium oxide (Bi12GeO20) single crystals are measured from room temperature down to 10 K. All the reflectivity spectra are fitted to a complex dielectric function ε(ω) in the factorised form. Phonon modes at low frequency are found to develop upon decreasing temperature and gain considerable spectrum weight below 150 K. The temperature-dependent static dielectric constants are obtained from the Lyddane-Sachs-Teller relation based on the obtained oscillator parameters. The dielectric constants are found to increase upon decreasing temperature, which is attributed to the charge transfer among the ions in the unit cell with the temperature varying. 展开更多
关键词 infrared reflectivity dielectric properties PHONON
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Possible Relevance of the Allende Meteorite Conditions in Prebiotic Chemistry: An Insight into the Chondrules and Organic Compounds
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作者 Alejandro Heredia Barbero Héctor G. Vázquez López +8 位作者 Adriana L. Meléndez López Jorge A. Cruz Castañeda Daniel Luna Laviada Karina E. Cervantes de la Cruz Victor Meza Laguna Vladimir A. Basiuk Ivonne Rosales Chávez Alicia Negrón Mendoza Sergio Ramos Bernal 《Advances in Biological Chemistry》 2023年第3期82-99,共18页
The study of the mineral and organic content of the Allende meteorite is important for our understanding of the molecular evolution of the universe as well as the ancient Earth. Previous studies have characterized the... The study of the mineral and organic content of the Allende meteorite is important for our understanding of the molecular evolution of the universe as well as the ancient Earth. Previous studies have characterized the magnetic minerals present in ordinary and carbonaceous chondrites, providing information on the evolution of magnetic fields. The interaction of organic compounds with magnetic minerals is a possible source of chemical diversity, which is crucial for molecular evolution. Carbon compounds in meteorites are of great scientific interest for a variety of reasons, such as their relevance to the origins of chirality in living organisms. This study presents the characterization of organic and mineral compounds in the Allende meteorite. The structural and physicochemical characterization of the Allende meteorite was accomplished through light microscopy, powder X-ray diffraction with complementary Rietveld refinement, Raman and infrared spectroscopy, mass spectrometry, scanning electron microscopy, and atomic force microscopy using magnetic signal methods to determine the complex structure and the interaction of organic compounds with magnetic Ni-Fe minerals. The presence of Liesegang-like patterns of chondrules in fragments of the Allende structure may also be relevant to understanding how the meteorite was formed. Other observations include the presence of magnetic materials and nanorod-like solids with relatively similar sizes as well as the heterogeneous distribution of carbon in chondrules. Signals observed in the Raman and infrared spectra resemble organic compounds such as carbon nanotubes and peptide-like molecules that have been previously reported in other meteorites, making the Mexican Allende meteorite a feasible sample for the study of the early Earth and exoplanetary bodies. 展开更多
关键词 Allende Meteorite Carbonaceous Chondrite Light Microscopy X-Ray Diffraction with the Rietveld Method Raman Spectroscopy Attenuated Total reflectance infrared Spectroscopy Mass Spectrometry Scanning Electron Mi-croscopy Energy Dispersive X-Ray Spectroscopy Magnetic Force Microscopy
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Preparation and Properties of TiO2-Coated Hollow Glass Microspheres as Thermal Insulation Materials for Energy-Saving Buildings
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作者 Chunyu Wu Weilin Wang Huiming Ji 《Transactions of Tianjin University》 EI CAS 2020年第4期283-291,共9页
A hollow glass microsphere(HGM)/TiO2 composite hollow sphere was successfully prepared via a simple precipitation method.The TiO2 coating layers grew on the surface of the HGMs that range from 20 to 50μm in diameter ... A hollow glass microsphere(HGM)/TiO2 composite hollow sphere was successfully prepared via a simple precipitation method.The TiO2 coating layers grew on the surface of the HGMs that range from 20 to 50μm in diameter as nanoparticles with the formation of the SiO Ti bonds.The growth mechanism accounting for the formation of the TiO2 nanolayers was proposed.The morphology,composition,thermal insulation properties,and visible-near infrared(VIS-NIR)refl ectance of the HGMs/TiO2 composite hollow spheres were characterized.The VIS-NIR reflectance of the HGMs/TiO2 composite hollow spheres increased by more than 30%compared to raw HGMs.The thermal conductivity of the particles is 0.058 W/(m K).The result indicates that the VIS-NIR reflectance of the composite hollow spheres is strongly influenced by the coating of TiO2.The composite hollow spheres were used as the main functional filler to prepare the organic-inorganic composite coatings.The glass substrates coated by the organic-inorganic coatings had lower thermal conductivity and higher near infrared reflectivity.Therefore,the HGMs/TiO2 composite hollow spheres can reflect most of the solar energy and effectively keep out the heat as a thermal insulation coating for energy-saving constructions. 展开更多
关键词 TIO2 Hollow glass microspheres Thermal insulation materials Near infrared reflectance
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Synchronous line-tracking robots based on STM 32 被引量:1
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作者 朱晓莉 李世光 +2 位作者 张锴 陈曰印 孟强强 《Journal of Measurement Science and Instrumentation》 CAS 2013年第1期58-62,共5页
A pair of synchronous line-tracking robots based on STM 32 are designed.Each robot is actually a small intelligent car with seven reflective infrared photoelectric sensors ST 188 installed in the front to track the li... A pair of synchronous line-tracking robots based on STM 32 are designed.Each robot is actually a small intelligent car with seven reflective infrared photoelectric sensors ST 188 installed in the front to track the line.Two rear wheels each driven by a moter are the driving wheels,while each moter is driven by an H-bridge circuit.The running direction is controlled by the turning of a servo fastened to the front wheel and the adjustment of speed difference between the rear wheels.Besides,the light-adaptive line-tracking can be performed.The speeds of the motors are controlled by adjusting pulse-width modulation(PWM)values and an angular displacement transducer is used to detect the relative position of the cars in real time.Thus,the speeds of the cars can be adjusted in time so that the synchronism of the cars can be achieved.Through experiments,the fast and accurate synchronous tracking can be well realized. 展开更多
关键词 STM 32 synchronous line-tracking robot intelligent car reflective infrared photoelectric sensor angular displacement transducer
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Thermal stability and hydration behavior of ritonavir sulfate:A vibrational spectroscopic approach 被引量:1
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作者 Kaweri Gambhir Parul Singh +1 位作者 Deepak K.Jangir Ranjana Mehrotra 《Journal of Pharmaceutical Analysis》 SCIE CAS 2015年第6期348-355,共8页
Ritonavir sulfate is a protease inhibitor widely used in the treatment of acquired immunodeficiency syndrome. In order to elucidate the inherent stability and sensitivity characteristics of ritonavir sulfate, it was i... Ritonavir sulfate is a protease inhibitor widely used in the treatment of acquired immunodeficiency syndrome. In order to elucidate the inherent stability and sensitivity characteristics of ritonavir sulfate, it was investigated under forced thermal and hydration stress conditions as recommended by the Inter- national Conference on Harmonization guidelines. In addition, competency of vibrational (infrared and Raman) spectroscopy was assessed to identify structural changes of the drug symbolizing its stress degradation. High performance liquid chromatography was used as a confirmatory technique for both thermal and hydration stress study, while thermogravimetric analysis]differential thermal analysis and atomic force microscopy substantiated the implementation of vibrational spectroscopy in this frame- work. The results exhibited high thermal stability of the drug as significant variations were observed in the diffuse reflectance infrared Fourier transform spectra only after the drug exposure to thermal radiations at 100 ℃. Hydration behavior of ritonavir sulfate was evaluated using Raman spectroscopy and the value of critical relative humidity was found to be 〉 67%. An important aspect of this study was to utilize vibrational spectroscopic technique to address stability issues of pharmacological molecules, not only for their processing in pharmaceutical industry, but also for predicting their shelf lives and suitable storage conditions. 展开更多
关键词 Ritonavir sulfateDiffuse reflectance infrared Fourier trans-form spectroscopyRaman spectroscopyThermal degradationHydration
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Responses of Transmembrane Peptide and Lipid Chains to Hydrophobic Mismatch
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作者 YANG Lei LI Jian-tao +1 位作者 QI Hai-yan LI Fei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第4期732-736,共5页
Hydrophobic mismatch between the hydrophobic length of membrane proteins and hydrophobic thickness of membranes is a crucial factor in controlling protein function and assembly.We combined fluorescence with circular d... Hydrophobic mismatch between the hydrophobic length of membrane proteins and hydrophobic thickness of membranes is a crucial factor in controlling protein function and assembly.We combined fluorescence with circular dichroism(CD) and attenuated total reflection infrared(ATR-IR) spectroscopic methods to investigate the behaviors of the peptide and lipids under hydrophobic mismatch using a model peptide from the fourth transmembrane domain of natural resistance-associated macrophage protein 1(Nramp1),the phosphatidylcholines(PCs) and phosphatidylglycerols(PGs) with different lengths of acyl chains(14:0,16:0 and 18:0).In all PG lipid membranes,the peptide forms stable α-helix structure,and the helix axis is parallel to lipid chains.The helical span and orientation hardly change in varying thickness of PG membranes,while the lipid chains can deform to accommodate to the hydrophobic surface of embedded peptide.By comparison,the helical structures of the model peptide in PC lipid membranes are less stable.Upon incorporation with PC lipid membranes,the peptide can deform itself to accommodate to the hydrophobic thickness of lipid membranes in response to hydrophobic mismatch.In addition,hydrophobic mismatch can increase the aggregation propensity of the peptide in both PC and PG lipid membranes and the peptide in PC membranes has more aggregation tendency than that in PG membranes. 展开更多
关键词 Hydrophobic mismatch Transmembrane peptide Fluorescence Circular dichroism(CD) Attenuated total reflection infrared(ATR-IR)
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Comparison and rapid prediction of lignocellulose and organic elements of a wide variety of rice straw based on near infrared spectroscopy 被引量:3
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作者 Abdoulaye Aguibou Diallo Zengling Yang +3 位作者 Guanghui Shen Jinyi Ge Zichao Li Lujia Han 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2019年第2期166-172,共7页
Rice straw is a major kind of biomass that can be utilized as lignocellulosic materials and renewable energy.Rapid prediction of the lignocellulose(cellulose,hemicellulose,and lignin)and organic elements(carbon,hydrog... Rice straw is a major kind of biomass that can be utilized as lignocellulosic materials and renewable energy.Rapid prediction of the lignocellulose(cellulose,hemicellulose,and lignin)and organic elements(carbon,hydrogen,nitrogen,and sulfur)of rice straw would help to decipher its growth mechanisms and thereby improve its sustainable usages.In this study,364 rice straw samples featuring different rice subspecies(japonica and indica),growing seasons(early-,middle-,and late-season),and growing environments(irrigated and rainfed)were collected,the differences among which were examined by multivariate analysis of variance.Statistic results showed that the cellulose content exhibited significant differences among different growing seasons at a significant level(p<0.01),and the contents of cellulose and nitrogen had significant differences between different growing environments(p<0.01).Near infrared reflectance spectroscopy(NIRS)models for predicting the lignocellulosic and organic elements were developed based on two algorithms including partial least squares(PLS)and competitive adaptive reweighted sampling-partial least squares(CARS-PLS).Modeling results showed that most CARS-PLS models are of higher accuracy than the PLS models,possibly because the CARS-PLS models selected optimal combinations of wavenumbers,which might have enhanced the signal of chemical bonds and thereby improved the predictive efficiency.As a major contributor to the applications of rice straw,the nitrogen content was predicted precisely by the CARS-PLS model.Generally,the CARS-PLS models efficiently quantified the lignocellulose and organic elements of a wide variety of rice straw.The acceptable accuracy of the models allowed their practical applications. 展开更多
关键词 rice straw near infrared reflectance spectroscopy models rapid prediction competitive adaptive reweighted sampling partial least-squares LIGNOCELLULOSE
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Highly efficient photo-thermal synergistic catalysis of CO_(2)methanation over La1-xCexNiO_(3)perovskite-catalyst
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作者 Ting Li Zhen-Yu Zhang +5 位作者 De-Cun Luo Bo-Yu Xu Rong-Jiang Zhang Ji-Long Yao Dan Li Tao Xie 《Nano Research》 SCIE EI CSCD 2024年第9期7945-7956,共12页
Solar-driven photo-thermal catalytic CO_(2)methanation reaction is a promising technology to alleviate the problems posed by greenhouse gases emissions.However,designing advanced photo-thermal catalysts remains a rese... Solar-driven photo-thermal catalytic CO_(2)methanation reaction is a promising technology to alleviate the problems posed by greenhouse gases emissions.However,designing advanced photo-thermal catalysts remains a research challenge for CO_(2)methanation reaction.In this work,a series of ABO3(A=lanthanide,B=transition metal)perovskite catalysts with Ce-substituted LaNiO3(La1-xCexNiO3,x=0,0.2,0.5,0.8,1)were synthesized for CO_(2)methanation.The La0.2Ce0.8NiO3 exhibited the highest CH4 formation rate of 258.9 mmol·g^(-1)·hcat-1,CO_(2)conversion of 55.4%and 97.2%CH4 selectivity at 300℃with the light intensity of 2.9 W·cm^(-2).Then the catalysts were thoroughly analyzed by physicochemical structure and optical properties characterizations.The partial substitution of the A-site provided more active sites for the adsorption and activation of CO_(2)/H_(2).The sources of the active sites were considered to be the oxygen vacancies(Ov)created by lattice distortions due to different species of ions(La^(3+),Ce^(4+),Ce^(3+))and exsolved Ni0 by H_(2)reduction.The catalysts have excellent light absorption absorbance and low electron-hole(e-/h+)recombination rate,which greatly contribute to the excellent performance in photo-thermal synergistic catalysis(PTC)CO_(2)methanation.The results of in situ irradiated electron paramagnetic resonance spectrometer(ISI-EPR)and ISI-X-ray photoelectron spectroscopy(XPS)indicated that the aggregation of unpaired electrons near the defects and Ni metal(from La and Ce ions to Ov and Ni0)accelerated adsorption and activation of CO_(2)/H_(2).At last,the catalyst properties and structure were correlated with the proposed reaction mechanism from the in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)measurements.The in situ precipitation of the B-site enhanced the dispersion of Ni,while its enriched photoelectrons upon illumination further promote hydrogen dissociation.More H^(*)spillover accelerated the rate-determining step(RDS)of HCOO*hydrogenation.This work provides the theoretical basis for the development of catalysts and industrial application. 展开更多
关键词 photo-thermal catalysis CO_(2)methanation PEROVSKITE A-site substitution in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)
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Cu/Mo2C synthesized through Anderson-type polyoxometalates modulate interfacial water structure to achieve hydrogen evolution at high current density
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作者 Dunyuan Jin Fen Qiao +6 位作者 Yan Zhou Junfeng Wang Kecheng Cao Jing Yang Jikang Zhao Lei Zhou Haitao Li 《Nano Research》 SCIE EI CSCD 2024年第4期2546-2554,共9页
The development of efficient non-precious metal catalysts is important for the large-scale application of alkaline hydrogen evolution reaction(HER).Here,we synthesized a composite catalyst of Cu and Mo_(2)C(Cu/Mo_(2)C... The development of efficient non-precious metal catalysts is important for the large-scale application of alkaline hydrogen evolution reaction(HER).Here,we synthesized a composite catalyst of Cu and Mo_(2)C(Cu/Mo_(2)C)using Anderson-type polyoxometalates(POMs)synthesized by the facile soaking method as precursors.The electronic interaction between Cu and Mo_(2)C drives the positive charge of Cu,alleviating the strong adsorption of hydrogen at the Mo site by modulating the d-band center of Mo_(2)C.By studying the interfacial water structure using in situ attenuated total reflection surface-enhanced infrared absorption spectroscopy(ATR-SEIRAS),we determined that the positively charged Cu crystals have the function of activating water molecules and optimizing the interfacial water structure.The interfacial water of Cu/Mo_(2)C contains a large amount of free water,which could facilitate the transport of reaction intermediates.Due to activated water molecules and optimized interfacial water structure and hydrogen adsorption energy,the overpotential of Cu/Mo_(2)C is 24 mV at a current density of 10 mA·cm^(-2) and 178 mV at a current density of 1000 mA·cm^(-2).This work improves catalyst performance in terms of interfacial water structure optimization and deepens the understanding of water-mediated catalysis. 展开更多
关键词 electrocatalytic hydrogen production interfacial water charge transport d band center in situ attenuated total reflection surface-enhanced infrared absorption spectroscopy(ATR-SEIRAS)
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Far Infrared Optical Properties of Bulk Wurtzite Zinc Oxide Semiconductor
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作者 Pohkok Ooi Saicheong Lee +2 位作者 Shashiong Ng Zainuriah Hassan Haslan Abu Hassan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2011年第5期465-470,共6页
Polarized far infrared (FIR) reflectance technique was applied to study the optical properties of a bulk wurtzite zinc oxide (ZnO) single crystal. Room temperature polarized FIR reflectance spectra were taken at v... Polarized far infrared (FIR) reflectance technique was applied to study the optical properties of a bulk wurtzite zinc oxide (ZnO) single crystal. Room temperature polarized FIR reflectance spectra were taken at various angles of incidence, from 20°to 70°. The theoretical polarized FIR reflectance spectra were simulated based on the anisotropic dielectric function model. Good agreement was achieved between the experimental and the theoretical FIR reflectance spectra. Through this work, a complete set of reststrahlen parameters of a bulk wurtzite ZnO at the Brillouin zone centre was obtained. Additionally, other FIR optical properties such as the real and the imaginary parts of the complex dielectric function, real and imaginary parts of the refractive index, the absorption coefficient and the reciprocal of the absorption coefficient were also obtained by using numerical calculation. 展开更多
关键词 Zinc oxide Far infrared POLARIZATION infrared reflectance
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New design for highly durable infrared-reflective coatings
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作者 Chaoquan Hu Jian Liu +8 位作者 Jianbo Wang Zhiqing Gu Chao Li Qian Li Yuankai Li Sam Zhang Chaobin Bi Xiaofeng Fan Weitao Zheng 《Light(Science & Applications)》 SCIE EI CAS CSCD 2017年第1期25-35,共11页
The fundamental challenge in designing durable infrared-reflective coatings is achieving the ideal combination of both high reflectivity and durability.Satisfying these competing demands is traditionally achieved by d... The fundamental challenge in designing durable infrared-reflective coatings is achieving the ideal combination of both high reflectivity and durability.Satisfying these competing demands is traditionally achieved by deposition of durable layers on highly reflective metals.We overturn the traditional logic of‘first reflectivity and then durability’and propose an alternative of‘first durability and then reflectivity’:First,a transition-metal compound is selected as a durable base;then its reflectivity is improved by incorporating silver/gold to form an alloy or by overcoating a multilayer stack.Two validation experiments prove that the new strategy works extremely well:the coatings thus obtained have infrared reflectivities close to that of aluminum,and their hardness and acid and salt corrosion resistances are 27–50,400–1500 and 7500–25000 times that of aluminum.The traditional mirror coating(e.g.,Al/SiO2 films)is more suitable for moderate environments,while our mirror coating that was obtained by the new strategy(e.g.,an Ag-doped hafnium nitride film)is more suitable for harsh environments,such as ones with dust,windblown sand,moisture,acid rain or salt fog.This work opens up new opportunities for highly durable infrared-reflective coatings and rejuvenates the study of transition metal compounds in a completely new area of optics. 展开更多
关键词 COATING DURABILITY infrared reflectivity optical design
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High Solar Energy Absorption and Human Body Radiation Reflection Janus Textile for Personal Thermal Management
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作者 Liang Fei Weidong Yu +2 位作者 Jialing Tan Yunjie Yin Chaoxia Wang 《Advanced Fiber Materials》 SCIE EI 2023年第3期955-967,共13页
A large of energy consumption is required for indoor and outdoor personal heating to ameliorate the comfortable and healthy conditions.Main personal thermal management strategy is to reflect mid-infrared human body ra... A large of energy consumption is required for indoor and outdoor personal heating to ameliorate the comfortable and healthy conditions.Main personal thermal management strategy is to reflect mid-infrared human body radiation for human surface temperature(THS)regulation.We demonstrate a visible Janus light absorbent/reflective air-layer fabric(Janus A/R fabric)that can passively reflect radiative heating meanwhile can actively capture the solar energy.A series of azobenzene derivatives functionalized with alkyl tails are reported to co-harvest the solar and phase-change energy.The THS covered by Janus A/R fabric can be heated up to~3.7°C higher than that covered by air-layer fabric in cold environment(5°C).Besides,integrating the thermo-and photo-chromic properties is capable of monitoring comfort THS and residue energy storage enthalpy,respectively.According to the colour monitors,intermittent irradiation approach is proposed to prolong comfortable-THS holding time for managing energy efficiently. 展开更多
关键词 Molecular solar energy storage AZOBENZENE infrared reflectance Personal energy management textile Colour change
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Effect of Cu loading content on the catalytic performance of Cu-USY catalysts for selective catalytic reduction of NO with NH_(3)
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作者 Jie Wan Haipeng Yang +5 位作者 Yijun Shi Yanjun Liu Jin Zhang Jun Zhang Gongde Wu Renxian Zhou 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第4期445-458,共14页
Series of Cu-USY zeolite catalyst with different Cu loading content were synthesized through simple impregnation method.The obtained catalysts were subjected to selective catalytic reduction of NOxwith NH_(3)(NH_(3)-S... Series of Cu-USY zeolite catalyst with different Cu loading content were synthesized through simple impregnation method.The obtained catalysts were subjected to selective catalytic reduction of NOxwith NH_(3)(NH_(3)-SCR) performance evaluation,structural/chemical characterizations such as X-ray diffraction (XRD),N2adsorption/desorption,H_(2)temperature-programmed reduction (H_(2)-TPR),NH_(3)temperature-programmed desorption (NH_(3)-TPD) as well as detailed in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) experiments including CO adsorption,NH_(3)adsorption and NO+O_(2)in situ reactions.Results show that Cu-USY with proper Cu loading (in this work 5Cu-USY with5 wt.%Cu) could be promising candidates with highly efficient NH_(3)-SCR catalytic performance,relatively low byproduct formation and excellent hydrothermal stability,although its SO_(2)poisoning tolerability needs alleviation.Further characterizations reveal that such catalytic advantages can be attributed to both active cu species and surface acid centers evolution modulated by Cu loading.On one hand,Cu species in the super cages of zeolites increases with higher Cu content and being more conducive for NH_(3)-SCR reactivity.On the other hand,higher Cu loading leads to depletion of Br?nsted acid centers and simultaneous formation of abundant Lewis acid centers,which facilitates NH_(4)NO_(3)reduction via NH_(3)adsorbed on Lewis acid centers,thus improving SCR reactivity.However,Cu over-introduction leads to formation of surface highly dispersed CuOx,causing unfavorable NH_(3)oxidation and inferior N2selectivity. 展开更多
关键词 NH_(3)-SCR USY zeolite Cu species Brønsted/Lewis acid centers Diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)
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Unraveling the interfacial effect of PdBi bimetallic catalysts on promoting CO_(2)electroreduction to formate
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作者 Wenhui Liu Lingtong Ding +5 位作者 Minmin Liu Xiao Wang Zhengrong Zhang Tian-Wen Jiang Shengjuan Huo Wen-Bin Cai 《Nano Research》 SCIE EI CSCD 2023年第8期10822-10831,共10页
Through interface engineering and content control strategy,a PdBi bimetallic interface structure was constructed for the first time to selectively convert CO_(2)to formate with a remarkably high Faraday efficiency(FEf... Through interface engineering and content control strategy,a PdBi bimetallic interface structure was constructed for the first time to selectively convert CO_(2)to formate with a remarkably high Faraday efficiency(FEformate)of 94%and a partial current density(jformate)of 34 mA·cm^(−2)at−0.8 V vs.reversible hydrogen electrode(RHE)in an H-cell.Moreover,the PdBi interface electrocatalyst even exhibited a high current density of 180 mA·cm^(−2)with formate selectivity up to 92%in a flow cell and could steadily operate for at least 20 h.Electrochemical in-situ attenuated total reflection surface enhanced infrared absorption spectroscopy(ATR-SEIRAS)confirmed that the PdBi interface could greatly weaken the adsorption of*CO intermediates due to electronic and geometric effects.Density functional theory(DFT)calculations also established that the PdBi interface regulated the CO_(2)-to-formate pathway by reducing the energy barrier toward HCOOH and largely weakening the adsorption of*CO intermediates on the catalyst surface.This study reveals that the unique PdBi bimetallic interface can provide a novel platform to study the reaction mechanism through combining in-situ ATR-SEIRAS and DFT calculations. 展开更多
关键词 carbon dioxide reduction reaction bimetallic PdBi interface engineering FORMATE in-situ attenuated total reflection surface enhanced infrared absorption spectroscopy(ATR-SEIRAS)
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Spectral feature characterization and nitrogen content prediction in soils with different particle sizes and moisture contents
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作者 He Yong Shao Yongni +2 位作者 Annia García Pereira Antihus Alexander Hernández Gómez Cen Haiyan 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2008年第1期43-50,共8页
The objective of this research is to analyze the influences of light source incidence angle,fiber height,moisture content,and particle size on loamy mixed soil spectra.Nitrogen(N)content calibration and cross-validati... The objective of this research is to analyze the influences of light source incidence angle,fiber height,moisture content,and particle size on loamy mixed soil spectra.Nitrogen(N)content calibration and cross-validation models at different moisture contents and particle sizes were obtained using partial least squares(PLS)analysis.Spectral data were collected using a spectrophotometer.Fiber height of 100 mm and light source angle at 45°were chosen to obtain the sharpest spectra without apparent scattering effect.The results show that moisture content and particle size strongly influenced the absorbance of the spectra,and a better N prediction model was obtained when the particle sizes were in the ranges of 0.5-1.0,1.0-2.0 and 2.0-5.0 mm,with the correlation coefficients(r)of 0.819,0.815 and 0.818,and standard errors of prediction(SEP)of 2.29,2.41 and 2.42 mg/kg,respectively.Poor N prediction model was obtained when the soil was kept in its natural moisture content with r of 0.575 and SEP of 3.275 mg/kg,compared to the performance of dried soil samples with r of 0.815 and SEP of 2.425 mg/kg. 展开更多
关键词 spectral feature prediction model soil moisture nitrogen content near infrared reflectance spectroscopy partial least squares
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