检索结果-南通市图书馆

Nano research 2016年第11期9卷 3291-3304页

作者： Tarachand Vikash Sharma Ranu Bhatt Vedachalaiyer Ganesan Gunadhor Singh Okram ugc-dae consortium for scientific research Indore 452001 India Technical Physics Division Bhabha Atomic Research Centre Mumbai 400085 India

This is the first report on the thermoelectric properties of a catalyst-free polyol method used to prepare stoichiometric Bi2-xCuxS3 samples, x = 0.1, 0.2, 0.3, 0.4, via hot pressing. Various systematic approaches to arrive at in their stoichiometric compositions are explored precisely with introduction of excess precursor of S. X-ray diffraction data analysis using Rietveld refinement confirms a polyhedral orthorhombic crystal structure with a space group Pnma, in contrast to Pbnm reported earlier. Raman data further substantiates this. X-ray photoelectron spectroscopy confirms the valence states of the constituent elements （Bi^3＋, Cu^2＋, and S^2-） and energy dispersive X-ray analysis corroborates their compositions. The particle sizes of the pure Bi2S3 nanoparticles were 20, 35, and 82 nm as determined from the Scherrer formula, atomic force microscopy, and dynamic light scattering, respectively. Their transmission electron microscopy image shows rod-like nanostructures elongated in the 〈010〉 direction with an average diameter of 23 nm and a length of several hundreds of nanometers. A 34% improvement in the thermoelectric figure of merit is observed for Bi.6Cu0.4S3 as compared to pure Bi2S3 at 300 K.

关键词： Bi2S3 polyol nanorods thermoelectrics

Comparison of Air Pollution−Mortality Associations Using Observed Particulate Matter Concentrations and Reanalysis Data in 33 Spanish Cities

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Environment & Health 2024年第3期2卷 161-169页

作者： Dominic Roye Carmen Íñiguez Aurelio Tobias Climate research Foundation 28003 MadridSpainSpanish Consortium for Research on Epidemiology and Public Health(CIBERESP)28029 MadridSpain Institute of Environmental Assessment and Water research(IdaeA) Spanish Council for Scientific Research(CSIC)08034 BarcelonaSpain

Air pollution poses a health hazard in all ***,complete data on ambient particulate matter(PM)concentrations are not available in all world *** data is already a valuable source of exposure data in epidemiological studies examining the relationship between temperature and ***,the performance of reanalysis data in assessing the short-term health effects of particulate air pollution remains *** assessed the performance of CAMS reanalysis(EAC4)data from the European centre for Medium-Range Weather Forecasts,compared with daily PM concentrations from field monitoring stations,to estimate short-term exposure to PM with an aerodynamic diameter less than 10μm(PM_(10))on daily mortality in 33 Spanish provincial capital cities using a two-stage time series regression *** shape of the PM_(10)distribution varied substantially between PM observations and CAMS global reanalysis of atmospheric composition(EAC4)reanalysis data,with correlation ranging from 0.21 to *** pooled mortality risk for a 10μg/m^(3)increase in PM_(10)showed similar estimates using PM concentrations{relative risks(RR)=1.007,95%confidence intervals(95%CI)=[1.002,1.011]}and EAC4 reanalysis data(RR=1.011,95%CI=[1.006,1.015]).However,the city-specific PM_(10)beta coefficients estimated using PM concentrations and EAC4 reanalysis data showed a low correlation(r=0.22).The use of reanalysis data should be approached with caution when assessing the association between particulate matter air pollution and health outcomes,particularly in cities with small populations.

关键词： Air pollution particulate matter PM_(10) reanalysis EAC4 mortality Spain time series regression

Multi-omics:Powerful accelerator for uncovering plant specialized metabolic pathways:The case of leonurine

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2024年第1期17卷 13-15页

作者： Priyanka Gupta Anuj Sharma Dinesh A.Nagegowda Molecular Plant Biology and Biotechnology Lab CSIR-Central Institute of Medicinal and Aromatic PlantsResearch CentreBengaluru 560065India Academy of scientific and Innovative research Ghaziabad 201002India

As sessile organisms,plants employ a unique adaptive strategy to survive harsh terrestrial environments and defend against or interact with coevolving animals and *** strategy involves expanding their metabolic systems,resulting in the production of plant specialized metabolites(PSMs)or natural ***,PSMs constitute a highly diverse group of compounds based on their common core structure,comprising terpenoids,phenylpropanoids,benzenoids,alkaloids and nitrogen-containing compounds,glucosinolates,indoles and sulfur-containing indole compounds,phenolics,and fatty acid derivatives(Garagounis et al.,2021).

关键词： expanding alkaloids sulfur

Dielectric relaxation and conduction mechanism in Aurivillius ceramic Bi_(5)Ti_(3)FeO_(15)

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2021年第6期28卷 1063-1071页

作者： Rasmita Jena K.Chandrakanta P.Pal Md.F.Abdullah S.D.Kaushik A.K.Singh Department of Physics and Astronomy National Institute of Technology RourkelaRourkela-769008OdishaIndia ugc-dae consortium for scientific research mumbai centre BARCMumbai-400085India

For this study,we synthesized Aurivillius Bi_(5)Ti_(3)FeO_(15) ceramic using the generic solid-state reaction route and then performed roomtemperature X-ray diffraction to confirm that the compound had a single phase with no *** surface morphology of the prepared sample was observed to contain microstructural grains approximately 0.2–2μm in *** dielectric properties of the sample were determined as a function of frequency in a range of approximately 100 Hz to 1 MHz at various temperatures(303 K≤T≤773 K).Nyquist plots of the impedance data were found to exhibit a semi-circular arc in the high-temperature region,which is explained by the equivalent electrical circuit(R_(1)C_(1))(R_(2)QC_(2)),where R_(1) and R_(2) represent the resistances associated with the grains and grain boundaries,respectively,C_(1) and C_(2) are the respective capacitances,and Q is the constant phase element(CPE),which accounts for non-Debye type of *** results indicate that both the resistance and capacitance of the grain boundaries are more prominent than those of the *** alternating current(ac)conductivity data were analyzed based on the Jonscher universal power law,which indicated that the conduction process is dominated by the hopping *** calculated activation energies of the relaxation and conduction processes were very similar(0.32 to 0.53 eV),from which we conclude that the same type of charge carriers are involved in both processes.

关键词： Nyquist plot impedance spectroscopy activation energy ac conductivity hopping

Optical characterization of nano-sized organic carbon particles emitted from a small gasoline engine

在线全文

学校读者我要写书评

暂无评论

Particuology 2013年第3期11卷 249-255页

作者： Bireswar Paul Amitava Datta Aparna Datta Abhijit Saha Department of Power Engineering Jadavpur University ugc-dae consortium for scientific research

The nano-sized organic carbon （NOC） particles emitted from a small gasoline engine were characterized using various ex situ optical techniques to assess their hazardous impact. The exhaust gas was sampled iso-kinetically by a quartz probe and passed through de-ionized water to gather the hydrophilic car- bonaceous particulates as hydrosol. The hydrodynamic diameter of the particles ranged between 1.7 and 3.6 nm at no load, with a mean diameter of 2.4 nm. The particle size in the engine exhaust was found to increase at higher loads, which is attributed to coagulation of the particles. The chemical structure of the particles was analyzed using UV-vis and infra-red spectroscopy. Both the band gap energy and oscillator strength data evaluated from the UV-vis absorbance showed that the NOC particles contained polyaromatic hydrocarbon structures with three to five aromatic rings. Infra-red spectroscopy analysis further confirmed the presence of aliphatic and carbonyl functionalities in the aromatic structures of the particles. The fine size of the particles, their high number concentration for the type of the engine under study and their structural features, make the particles extremely hazardous for environment and health.

关键词： Gasoline engine Combustion Emission Carbon nano-particle Characterization

Effect of Co substitution on the structural,dielectric and optical properties of KBiFe_(2)O_(5)

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2021年第11期28卷 1861-1867页

作者： K.Chandrakanta R.Jena P.Pal Md.F.Abdullah S.D.Kaushik A.K.Singh Department of Physics and Astronomy National Institute of TechnologyRourkela-769008OdishaIndia ugc-dae consortium for scientific research mumbai centre R-5 ShedBARCMumbai-400085India

Cobalt(Co)-modified brownmillerite KBiFe_(2)O_(5)(KBFO;[KBiFe_(2(1−x))Co_(2x)O_(5)(x=0,0.05)])polycrystalline is synthesized following the solid-state reaction *** refinement of X-ray diffraction data confirmed the phase purity of KBFO and KBiFe_(1.9)Co_(0.1)O_(5)(KBFCO).The optical bandgap energy(Eg)of KBFO decreased from 1.59 to 1.51 eV because of Co *** decrease in bandgap can be attributed to the tilting of the Fe–O tetrahedral structure of *** observed room-temperature Raman peaks of KBFCO shifted by 3 cm^(−1) toward a lower wavenumber than that of *** shift in Raman active modes can be attributed to the change in the bond angles and bond lengths of the Fe–O tetrahedral structure and modification in response to oxygen deficiency in KBFO because of Co *** with that of KBFO,the frequency-dependent dielectric constant and dielectric loss of KBFCO decrease at room temperature,which is a consequence of the reduction in oxygen migration and modification in response to vibrational modes present in the sample.

关键词： brownmillerite rietveld refinement Raman spectroscopy bandgap

Comprehensive analysis of uncertainty quantification for the^(58)Ni(n,p)^(58)Co reaction cross section

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第9期48卷 170-175页

作者： Mahesh Choudhary Aman Sharma Namrata Singh Mahima Upadhyay Punit Dubey A.Gandhi Akash Hingu G Mishra Sukanya De L.S.Danu Ajay Kumar R.G.Thomas Saurav Sood Sajin Prasad S.Mukherjee I.N.Ruskov Yu.N.Kopatch A.Kumar Department of Physics Banaras Hindu UniversityVaranasi 221005India Horia Hulubei National Institute of Physics and Nuclear Engineering-IFIN-HH Bucharest 077125Romania Department of Physics The Maharaja Sayajirao University of BarodaVadodara 390002India Nuclear Physics Division Bhabha Atomic Research CentreMumbai 400085India Health Physics Division Bhabha Atomic Research CentreMumbai 400085India Department of Electrical Power Engineering Brno University of TechnologyBrno 61600Czech Republic Institute for Nuclear research and Nuclear Energy Bulgarian Academy of SciencesSofia 1784Bulgaria Joint Institute for Nuclear research(JINR) Dubna 141980Russia

In this study,we measured the^(58)Ni(n,p)^(58)Co reaction cross section with neutron energies of 1.06,1.86,and 2.85 *** cross section was measured using neutron activation techniques andγ-ray spectroscopy,and it was compared with cross section data available in the ***,we calculated the covariance matrix of the measured cross section for the aforementioned nuclear *** uncertainties of the theoretical calculation for^(58)Ni(n,p)^(58)Co reaction cross section were calculated via Monte Carlo *** this study,we used uncertainties in the optical model and level density parameters to calculate uncertainties in the theoretical cross *** theoretical calculations were performed by using *** this study,we aim to analyze the effect of uncertainties of the nuclear model input as well as different experimental variables used to obtain the values of reaction cross section.

关键词： ^(58)Ni(n p)^(58)Co reaction γ-ray spectroscopy uncertainty quantification of cross section covariance analysis

Wastewater treatment using Fe-doped perovskite manganites by photocatalytic degradation of methyl orange,crystal violet and indigo carmine dyes in tungsten bulb/sunlight

在线全文

学校读者我要写书评

暂无评论

稀土学报:英文版 2023年第9期41卷 1311-1322,I0002页

作者： Brajendra Singh Priyanka Singh Saiqua Siddiqui Divyanshu Singh Mukul Gupta Materials Chemistry Lab Centre of Material SciencesUniversity of AllahabadPrayagraj21002India ugc-dae consortium for scientific research University CampusKhandwa Road Indore452001India

We documented(ⅰ) the decolorization of wastewater in visible light,which contains methyl orange,crystal violet and indigo carmine dyes,using La_(0.7)Sr_(0.3)Mn_(1-x)Fe_(x)O_(3)(x=0.0,0.05,0.1 and 0.5) manganites and(ⅱ) efficient separation of photocatalysts from water using magnetic *** ceramic photocatalysts were sintered at 1050℃ for 12 *** were characterized by X-ray diffraction(XRD),soft X-ray absorption spectroscopy(SXAS),Fourier transform infrared spectroscopy(FTIR) and UV-visible diffuse reflectance spectroscopy(DRS).SXAS studies show the presence of Mn(Mn^(3+)/Mn^(4+)) and Fe(Fe^(3+)/Fe^(4+)) mixes valences in Fe-doped *** band gap is found in visible light range for La_(0.7)Sr_(0.3)Mn_(1-x)Fe_(x)O_(3)(x=0.0,0.05,0.1) ***_(0.7)Sr_(0.3)MnO_(3) degrades 94.6% methyl orange in7 min,81.9% crystal violet in 10 min and 99.1% indigo carmine in 5 ***_(0.7)Sr_(0.3)Mn_(0.9)Fe_(0.1)O_(3) degrades the 92.6% methyl orange dye solution in 9 min,94.8% crystal violet in 25 min and 97.1% indigo carmine in3 *** and Fe doped manganites can be separated in 60 s from wastewater.

关键词： Synchrotron X-ray absorption Dye degradation Magnetic separation Mixed valences Rare earths Wastewater treatment

Multiferroic Consequence of Porous (BiFeO_3)_x–(BiCrO_3)_(1-x) Composite Thin Films by Novel Sol–Gel Method

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2018年第3期31卷 299-307页

作者： William Raja Victor Marikani Arumugam Thiruramanathan Pandirengan Madhavan Durairaj Raghavendra Reddy Varimalla Department of Physics Mepco Schlenk Engineering College Department of Chemistry Mepco Schlenk Engineering College ugc-dae consortium for scientific research University Campus

In this work,we have presented a spin-coating method to produce thin films started with pure BiCrO3（BCO）and ended up with BiFeO3（BFO）by increasing x values in the（BiFeO3）x-（BiCrO3）1-x *** the produced thin films have been crystallized at the annealing temperatures of 400 ℃ for 0.5 *** XRD and EDAX spectrums give insight that the two crystal phases related to BCO and BFO stayed together within the thin film *** analysis showed that the prepared composite had macroporous morphology with interconnected pores and its width（size）decreased with increasing x *** strong correlations are observed among the microstructure,dielectric,ferroelectric,ferromagnetic properties and Fe *** all composites,the composition of 0.75 shows an attractive magnetization,polarization,switching and improved dielectric behaviors at room *** increase in the multiferroic characteristics of 0.75 composition is due to arise of lower leakage current by causing reduction in oxygen vacancy density,and enhancement of super-exchange magnetic interaction between Fe3＋ and Cr3＋ at BFO/BCO interface *** result shows that the thin layer on Pt（111）/Ti/SiO2/Si substrate possesses simultaneously improved ferroelectric and ferromagnetic properties which make an inaccessible potential application for nonvolatile ferroelectric memories.

关键词： Multiferroic Dual-phase composites Spin-coating method NV-Fe-RAM PUND

Magnetic Phase Separation in Diluted Magnetic System:Zn1-xFexO

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2017年第6期30卷 521-527页

作者： Archita Mondal Sanchari Sarkar Neepamala Giri Souvik Chatterjee Ruma Ray Department of Physics Jadavpur UniversityKolkata 700 032India ugc-dae consortium for scientific research Kolkata CentreSector IIILB-8Salt LakeKolkata 700098India

Single-phase diluted magnetic systems Zn1-xFexO have been prepared by chemical route. Structural and spectroscopic （UV-Vis and Mossbauer） studies indicate the incorporation of Fe^3＋ ions in the lattice sites. The UV-Vis results point to a systematic increase in the band gap with increasing Fe doping. The room temperature magnetization of Zni-xFexO indicates a paramagnetic behavior which is in accordance with the Mossbauer results, illustrating quadrupolar doublet. At low temperature, the zero-field-cooled （ZFC） magnetization shows a cusp and this temperature increases systematically with decreasing particle size. The weak exchange bias effect manifested by a M-H loop shift is observed for x = 0.03. This shift is accompanied by the enhancement of coercivity. The dc magnetization results suggest the coexis tence of ferromagnetic and antiferromagnetic exchange interactions for low doping of Fe, i.e., for x = 0.03.

关键词： Diluted magnetic system Optical band gap Moissbauer Exchange bias effect