检索结果-南通市图书馆

Calculation of the Exchange Interaction Constant Between the Rare-Earh and the Transition Metal Sub-lattices in R_(2)Fe_(17-x)M_(x)(M=Al or Ga)

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2000年第6期17卷 444-445页

作者： HAO yan-ming Department of Physics Tianjin Normal UniversityTianjin 300074

A precise calculation of the exchange interaction constant JnT between the rare-earth sub-lattice and the transition metal sub-lattice in R_(2)Fe_(17-x)M_(x)(R:rare-earth,M=Al or Ga)compounds is *** calculated values for Tb_(2)Fe_(17-x)Ga_(x)(x=6 and 7)and Dy_(2)Fe_(17-x)Al_(x)(x=5,6,7 and 8)compounds are in excellent agreement with the values derived from the high-field measurement.

关键词： (x) measurement. rare

Identification and Validation of Single Nucleotide Polymorphisms in Poplar Using Publicly Expressed Sequence Tags

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

Journal of Integrative Plant Biology 2005年第12期47卷 1493-1499页

作者： bo ZHANG yan ZHOU Liang ZHANG Qiang ZHUGE ming-Xiu WANG Min-Ren HUANG Forest Genetics and Gene Engineering Laboratory Nanjing Forestry University Nanjing 210037 China Genomics and Bioinformatics Institute Hangzhou 310008 China

By using assembled expressed sequence tags （ESTs） from 14 different eDNA libraries that contain 84 132 sequences reads, 556 Populus candidate single nucleotide polymorphisms （SNPs） were identified. Because traces were not available from dbEST （http：//***/dbEST/***）, stringent filters were used to identify reliable candidate SNPs. Sequences analysis indicated that the main types of substitutions among candidate SNPs were A/G and T/C transitions, which accounted for 22.0% and 30.8%, respectively. One hundred and ten candidate SNPs were tested. As a result, 38 candidate SNPs were confirmed by directed sequencing of PCR products amplified from six different individuals. Thirteen new SNPs in intron regions were found and multiple SNPs were found to be located in both intron and exon regions of four contigs. Heterozygosis was found in all 47 candidate sites and five SNP sites were heterozygous in all six samples. This is the first report of SNP identification in a tree species which reveals that assembled ESTs from multiple libraries of the public database may provide a rich source of comparative sequences for an SNP search in the poplar genome.

关键词： expressed sequence tag poplar single nucleotide polymorphism.

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

单一相氧化钛柱撑磷酸锆的合成

天津化工 2004年第2期18卷 31-34页

作者：王明艳许瑞波许前会孙霞淮海工学院化学工程系江苏连云港222005

以XRD跟踪考察了不同制备因素对单一相氧化钛柱撑磷酸锆合成的影响,发现以TiSO42为钛源,在较短反应时间钛胶粒就可以嵌入磷酸锆层间达到平衡。详细考察了以TiSO42为钛源合成稳定的单一相氧化钛柱撑磷酸锆的最佳条件。

关键词：单一相氧化钛柱撑磷酸锆层间距 XRD

Simple preparation of C(CS)/g-C_(3)N_(4)/Co carbon aerogel and its catalytic performance for ammonium perchlorate

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第3期33卷 186-196页

作者： Yujie yan bo Jin Rufang Peng State Key Laboratory of Environment-friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang621010China

Biomass chitosan(CS)was used as a template,graphitic phase carbon nitride(g-C_(3)N_(4))with high nitrogen content and certain catalytic activity was used as a dopant,and nano-transition metal cobalt(Co)was used as a catalytic center *** carbon aerogel(C(CS)/g-C_(3)N_(4)/Co)with a three-dimensional network-like structure was prepared by assembling the three materials through experimental operations such as freeze-drying and high-temperature *** was demonstrated by scanning and transmission characterization that the CS in the carbon aerogel could provide more active sites for the cobalt nanoparticles,and the doping of graphite-phase carbon nitride as a template dispersed the cobalt nanoparticles and changed the conductivity of the *** investigate the catalytic effect of carbon aerogel on ammonium perchlorate(AP),it was investigated by differential thermal analyzer and TG thermal *** carbon aerogel was very effective in catalyzing AP,and the 10 wt% content of the catalyst reduced the AP pyrolysis peak from 703.9 to 595.5 *** to further investigate the synergistic effect of the three materials,further carbon aerogels such as C(CS)/Co,g-C_(3)N_(4)/Co were prepared and applied to catalyze AP,and the same ratio reduced the AP pyrolysis peak by 98.1℃ and 97.7℃.This result indicates a synergistic effect of the assembly of the three materials.

关键词： g-C_(3)N_(4) Chitosan Co Ammonium perchlorate Pyrolysis kinetics

Reactions of Chromium during the Calcination of Cement Clinker Produced Using Steel Slag

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2023年第4期38卷 834-841页

作者：何晨海 yan bo LI Fuzhou School of Materials Science and Engineering Wuhan University of TechnologyWuhan430070China Wuhan Rungong Technology Company Limited Wuhan430070China

We investigated the effects of calcination temperature(950-1450℃),steel slag content,and the total chromium content of steel slag on the Cr^(6+)contents of clinker samples produced using steel slags with different chromium ***,the reactions of chromium in clinker(produced using steel slag)during calcination were *** is found that Cr^(6+)conversion increases with increasing calcination temperature to 1250℃,reaching a maximum of 43%-79%,before decreasing to 18%-42%at 1450℃.Cr^(6+)is mainly formed by the oxidation of trivalent chromium(Cr^(3+))during the solid-phase reaction stage of clinker ***,the Cr^(6+)content of a clinker sample is proportional to the chromium content of its raw meal precursor and is mainly in the form of water-insoluble calcium chromate(CaCrO_(4)).The chromium in clinker is mainly distributed in tricalcium aluminate and tetracalcium aluminoferrite,however,some is present in silicate *** expect to inform the monitoring and control of the Cr^(6+)content of clinker(produced using steel slag)and resulting cement.

关键词： chromium cement clinker steel slag hexavalent chromium reaction characteristics

Tunability of Band Gaps of Programmable Hard-Magnetic Soft Material Phononic Crystals

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2022年第5期35卷 719-732页

作者： bo Li Wei yan Yuanwen Gao Department of Mechanics and Engineering Science College of Civil Engineering and MechanicsLanzhou UniversityLanzhou730000China Key Laboratory of Mechanics On Environment and Disaster in Western China The Ministry of Education of ChinaLanzhou UniversityLanzhou730000China

In this paper,the elastic wave band gap characteristics of two-dimensional hard-magnetic soft material phononic crystals(HmSM-PnCs)under the applied magnetic field are ***,the relevant material parameters of hard-magnetic soft materials(HmSMs)are obtained by the experimental *** the finite element model of the programmable HmSM-PnCs is established to calculate its band structure under the applied magnetic *** effects of some factors such as magnetic field,structure thickness,structure porosity,and magnetic anisotropy encoding mode on the band gap are *** results show that the start and stop frequencies and band gap width can be tunable by changing the magnetic *** magnetic anisotropy encoding mode has a remarkable effect on the number of band gaps and the critical magnetic field of band *** addition,the effect of geometric size on PnC structure is also *** the increase of the structure thickness,the start and stop frequencies of the band gap increase.

关键词： Phononic crystal Hard-magnetic soft materials Magnetic field Magnetic anisotropy encoding modes Structure thickness Band gap

Simultaneous quantification of greenhouse gas and nitric oxide emissions from subtropical conventional vegetable systems:a 2-site field case study in Sichuan Basin

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

Journal of Mountain Science 2021年第3期18卷 671-682页

作者： ZHANG bo-wen ZHOU ming-hua ZHU bo Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China

Quantification of greenhouse gases[nitrous oxide(N_(2)O)and methane(CH_(4))]and nitric oxide(NO)emissions from subtropical conventional vegetable systems through multi-site field measurements are needed to obtain accurate regional and global estimates.N2 O,NO and CH4 emissions from subtropical conventional vegetable systems were simultaneously measured at two different sites with hilly topography in the Sichuan basin,southwest China by using the static chamber gas chromatography *** showed that annual soil N_(2)O and NO fluxes for the treatment receiving N fertilizer ranged from 6.34-7.71 kg N ha^(-1) yr^(-1) and 0.69-0.85 kg N ha^(-1) yr^(-1),respectively,while decreased soil CH4 uptakes by 26.4%as compared with no N fertilizer addition across our two sites of ***,the average direct N2 O and NO emission factor(EFd)were 0.71%and 0.12%,respectively,which were both lower than the available EFd for subtropical conventional vegetable *** finding indicates that current regional and global estimates of N_(2)O and NO emissions from vegetable fields are likely *** N_(2)O emissions(3.42-3.62 kg N ha^(-1) yr^(-1))from the subtropical conventional vegetable systems were relatively high as compared with available field measurements worldwide,suggesting that background N_(2)O emissions cannot be ignored for regional estimate of N_(2)O emissions in subtropical ***,the significantly intra-and inter-annual variations in N_(2)O,CH_(4) and NO emissions were also observed in the present study,which could be explained by temporal variations of environmental variables(*** temperature and moisture).The differences in N_(2)O and NO EFd and CH_(4)emissions between various vegetable systems in particular under subtropical conditions should be taken into account when compiling regional or global inventories and proposing mitigation practices.

关键词： Subtropical vegetable system Nitrous oxide Nitric oxide Methane Emission factor Background emissions

Mean-Square Output Consensus of Heterogeneous Multi-Agent Systems with Multiplicative Noises in Dynamics and Measurements

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2023年第6期36卷 2364-2381页

作者： LIN bo LUO Shixian JIANG yan Guangxi Key Laboratory of Disaster Prevention and Engineering Safety Guangxi UniversityNanning530004China School of Electrical Engineering Guangxi UniversityNanning530004China

This paper studies the output consensus problem of heterogeneous linear stochastic multiagent systems with multiplicative noises in system parameters and measurements,where the system noise in each agent is allowed to be *** employing stochastic output regulation theory and the stochastic Lyapunov function approach,a composite controller embedded with stochastic output regulator equations(SOREs)and a stochastic dynamic compensator is designed to achieve the meansquare output consensus of the multi-agent *** implement the consensus algorithm,a sufficient condition for feasible solutions of the SOREs is first established in terms of Lyapunov and Selvester *** the time-varying SOREs are approximated by the Euler-Maruyama method combined with an a-posteriori partial estimation of the increments of the Brownian motion.A numerical example illustrates the theoretical results.

关键词： Heterogeneous multi-agent systems multiplicative noise output consensus stochastic output regulation

Microwave Assisted-extraction of Flavonols from Acanthopanax Senticosus Harms and High-performance Liquid Chromatography Analysis

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2009年第4期25卷 439-442页

作者： LIU yan-bo Department of Chemistry Baicheng Teacher＇s College Baicheng 137000 P. R. China

Flavonols were extracted from Acanthopanax Senticosus Harms by Soxhlet extraction（SE）,atmospheric pressure microwave-assisted extraction（AMAE） and pressurized microwave-assisted extraction（PMAE）.The influences of experimental conditions,such as concentration of ethanol in the eluent,microwave irradiation time,*** the extraction yield were *** flavonols（hyperin,rutin,quercitrin and quercetin） in the extracts were determined quantitatively by HPLC *** experimental results demonstrate the advantages of PMAE and AMAE over those of conventional SE,that is the extraction time is dramatically reduced,and the yields of flavonols are effective *** the yield of flavonols is higher and the extraction time is shorter by PMAE than those of AMAE,flavonols are easy to be decomposed over a certain time.

关键词： Acanthopanax Senticosus Harms Flavonols Extraction