检索结果-南通市图书馆

A comparison of corrosion inhibition of magnesium aluminum and zinc aluminum vanadate intercalated layered double hydroxides on magnesium alloys

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

Frontiers of Materials Science 2018年第2期12卷 198-206页

作者： Lian GUO Fen ZHANG Jun-Cai LU Rong-Chang zeng Shuo-Qi LI Liang SONG jian-min zeng College of Material Science and Engineering Shandong University of Science and Technology Qingdao 266590 China School of Materials Science and Engineering Guangxi University Nanning 530004 China

The magnesium aluminum and zinc aluminum layered double hydroxides intercalated with NO3^- （MgAl-NO3-LDH and ZnAl-NO3-LDH） were prepared by the coprecipitation method, and the magnesium aluminum and the zinc aluminum layered double hydroxides intercalated with VO; （MgAl-VOx-LDH and ZnAl-VOx-LDH） were prepared by the anion-exchange method. Morphologies, microstructures and chemical compositions of LDHs were investigated by SEM, EDS, XRD, FTIR, Raman and TG analyses. The immersion tests were carried to determine the corrosion inhibition properties of MgAl-VOx-LDH and ZnAl-VOx-LDH on AZ31 Mg alloys. The results showed that ZnAl-VOx-LDH possesses the best anion-exchange and inhibition abilities. The influence of treatment parameters on microstructures of LDHs were discussed. Additionally, an inhibition mechanism for ZnAl-VOx-LDH on the AZ31 magnesium alloy was proposed and discussed.

关键词： layered double hydroxides anion-exchange thermal stability magnesium alloys inhibition

Mo-V-Nb-O-based catalysts for low-temperature selective oxidation of Cα-OH lignin model compounds

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

Frontiers of Materials Science 2020年第1期14卷 52-61页

作者： Lu-Lu Zhang Kun Hao Rui-Kai Wang Xiu-Qiang Ma Tong Liu Liang Song Qing Yu Zhong-Wei Wang jian-min zeng Rong-Chang zeng College of Materials Science and Engineering Shandong University of Science and Technology579 Qianwangang RoadQingdao266590China College of Materials Science and Engineering Qingdao University of Science and Technology53 Zhengzhou RoadQingdao266000China ministry-Province Jointly-Constructed Cultivation Base for State Key Laboratory of Processing for Non-ferrous Metal and Featured Materials Guangxi University100 Daxue East RoadNanning530004China

Mo-V-Nb tri-component oxide catalysts were prepared and firstly used for the selective oxidation of Cα-OH lignin *** catalytic performance of the composite oxides was obviously enhanced due to the synergistic effects of Mo and V ***5-xVxO14 phase with a variable Mo/V ratio provided suitable active sites for the oxidative dehydrogenation(ODH)of Cα-OH lignin model *** optimized Mo-V-Nb molar composition was confirmed as Mo0.61V0.31Nb0.08Ox/TiO2,which exhibited the prominent catalytic activity with the turnover frequency of 1.04×10-3 mmol·g(cat)-1·*** at room temperature,the catalysts showed highly-efficient ODH reaction *** active phase for selective oxidation reaction and the inhibiting effect ofα-MoO3 phase were also discussed in the study.

关键词： selective oxidation secondary alcohol lignin model compound room temperature

Effect of CO_2 Enrichment on the Growth and Nutrient Uptake of Tomato Seedlings

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

Pedosphere 2007年第3期17卷 343-351页

作者： LI Juan ZHOU jian-min DUAN zeng-Qiang DU Chang-Wen WANG Huo-Yan State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 （China） Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 （China）

Exposing tomato seedlings to elevated CO2 concentrations may have potentially profound impacts on the tomato yield and quality. A growth chamber experiment was designed to estimate how different nutrient concentrations influenced the effect of elevated CO2 on the growth and nutrient uptake of tomato seedlings. Tomato (Hezuo 906) was grown in pots placed in controlled growth chambers and was subjected to ambient or elevated CO2 (360 or 720μL L-1) and four nutrient solutions of different strengths (1/2-, 1/4-, 1/8-, and 1/16-strength Japan Yamazaki nutrient solutions) in a completely randomized design. The results indicated that some agricultural characteristics of the tomato seedlings such as the plant height, stem thickness, total dry and fresh weights of the leaves, stems and roots, the G value (G value = total plant dry weight/seedling age), and the seedling vigor index (seedling vigor index = stem thickness/(plant height×total plant dry weight) increased with the elevated CO2, and the increases were strongly dependent on the nutrient solution concentrations, being greater with higher nutrient solution concentrations. The elevated CO2 did not alter the ratio of root to shoot. The total N, P, K, and C absorbed from all the solutions except P in the 1/8- and 1/16-strength nutrient solutions increased in the elevated CO2 treatment. These results demonstrate that the nutrient demands of the tomato seedlings increased at elevated CO2 concentrations.

关键词： CO2 enrichment nutrient strength nutrient uptake tomato seedlings

Inexact proximal gradient algorithm with random reshuffling for nonsmooth optimization

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2025年第1期68卷 219-237页

作者： Xia jianG Yanyan FANG Xianlin zeng jian SUN Jie CHEN National Key Lab of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center School of Electronic and Information Engineering Tongji University

Proximal gradient algorithms are popularly implemented to achieve convex optimization with nonsmooth regularization. Obtaining the exact solution of the proximal operator for nonsmooth regularization is challenging because errors exist in the computation of the gradient; consequently, the design and application of inexact proximal gradient algorithms have attracted considerable attention from researchers. This paper proposes computationally efficient basic and inexact proximal gradient descent algorithms with random reshuffling. The proposed stochastic algorithms take randomly reshuffled data to perform successive gradient descents and implement only one proximal operator after all data pass through. We prove the convergence results of the proposed proximal gradient algorithms under the sampling-without-replacement reshuffling *** computational errors exist in gradients and proximal operations, the proposed inexact proximal gradient algorithms can converge to an optimal solution neighborhood. Finally, we apply the proposed algorithms to compressed sensing and compare their efficiency with some popular algorithms.

关键词： proximal operator random reshuffling inexact computation compressed sensing nonsmooth optimization

梯度颗粒阳极固体氧化物燃料电池电性能的数值研究

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

工程热物理学报 2018年第8期39卷 1803-1808页

作者：付佩杨剑曾敏王秋旺西安交通大学热流科学与工程教育部重点实验室西安710049

本文通过建立梯度颗粒阳极固体氧化物燃料电池(Solid Oxide Fuel Cell,SOFC)的三维数学模型,系统地研究了梯度颗粒阳极SOFC的电性能,深入分析了梯度颗粒阳极对SOFC电性能的影响机理。研究发现,梯度颗粒阳极设计可以有效降低阳极内的活... 详细信息

本文通过建立梯度颗粒阳极固体氧化物燃料电池(Solid Oxide Fuel Cell,SOFC)的三维数学模型,系统地研究了梯度颗粒阳极SOFC的电性能,深入分析了梯度颗粒阳极对SOFC电性能的影响机理。研究发现,梯度颗粒阳极设计可以有效降低阳极内的活化极化、浓度极化和欧姆极化。在本文的参数设置下,梯度颗粒阳极设计的SOFC最大输出功率密度可达到0.90 W·cm^(-2),相比于颗粒尺寸为0.5μm、1.0μm和1.5μm的阳极SOFC,增幅分别为2.59%、10.30%和16.26%。因此,梯度颗粒阳极设计的SOFC可以显著提高电池的电性能。

关键词：固体氧化物燃料电池梯度颗粒阳极电性能极化损失

在线全文

学校读者我要写书评

暂无评论

我国青少年业余体育训练中的若干心理学问题

华中师范大学学报（自然科学版） 1999年第3期33卷 460-464页

作者：王斌王健郭敏曾庆肃华中师范大学体育系武汉430079

青少年业余体育训练是实现竞技体育战略目标的根本途径．针对青少年业余体育训练中存在的若干问题，应用现代心理学理论，从青少年业余体育训练的动力系统、运动技能学习、业余体育训练中的心理训练等几个方面进行探讨。

关键词：业余体育训练心理训练青少年心理学中国

Regulating crystallization and retarding oxidation in Sn-Pb perovskite via 1D cation engineering for high performance all-perovskite tandem solar cells

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 646-652页

作者： Ranran Liu Xin Zheng Zaiwei Wang Miaomiao zeng Chunxiang Lan Shaomin Yang Shangzhi Li Awen Wang min Li Jing Guo Xuefei Weng Yaoguang Rong Xiong Li Michael Gr?tzel Center for Mesoscopic Solar Cells Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Institute of Technology for Carbon Neutrality Shenzhen Institute of Advanced Technology Chinese Academy of Sciences School of Physics and Optoelectronic Engineering Hainan University Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO) Chinese Academy of Sciences School of Chemistry Chemical Engineering and Life Sciences State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology

All-perovskite tandem solar cells have the potential to surpass the theoretical efficiency limit of single junction solar cells by reducing thermalization ***,the challenges encompass the oxidation of Sn2+to Sn4+and uncontrolled crystallization kinetics in Sn-Pb perovskites,leading to nonradiative recombination and compositional heterogeneity to decrease photovoltaic efficiency and operational ***,we introduced an ionic liquid additive,1-ethyl-3-methylimidazolium iodide （EMIMI） into Sn-Pb perovskite precursor to form low-dimensional Sn-rich/pure-Sn perovskites at grain boundaries,which mitigates oxidation of Sn2+to Sn4+and regulates the film-forming dynamics of Sn/Pb-based perovskite *** optimized single-junction Sn-Pb perovskite devices incorporating EMIMI achieved a high efficiency of 22.87%.Furthermore,combined with wide-bandgap perovskite sub-cells in tandem device,we demonstrate 2-terminal all-perovskite tandem solar cells with a power conversion efficiency of 28.34%,achieving improved operational stability.

关键词： All-perovskite tandem solar cells Sn-Pb perovskite 1D Regulated crystallization Antioxidation

Mesospheric tide comparisons at low latitudes observed by two collocated meteor radars

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Earth and Planetary Physics 2025年第1期9卷 54-68页

作者： jian Li Wen Yi XiangHui Xue Jie zeng HaiLun Ye jianYuan Wang JinSong Chen Na Li TingDi Chen Chinese Academy of Sciences(CAS)Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology Anhui Mengcheng Geophysics National Observation and Research StationUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China Yunnan Kunming Electromagnetic Environment National Observation and Research Station Qujing Kunming 655000China

Accurate knowledge of mesospheric winds and waves is essential for studying the dynamics and climate in the mesosphere and lower thermosphere(MLT)*** this study,we conduct a comparative analysis of the mesosphere tidal results obtained from two adjacent meteor radars at low latitudes in Kunming,China,from November 2013 to December *** two radars operate at different frequencies of 37.5 MHz and 53.1 MHz,***,overall good agreement is observed between the two radars in terms of horizontal winds and tide *** results show that the dominant tidal waves of the zonal and meridional winds are diurnal and semidiurnal ***,we conduct an exhaustive statistical analysis to compare the tidal amplitudes and vertical wavelengths recorded by the dual radar systems,which reveals a high degree of alignment in tidal *** investigation includes variances and covariances of tidal amplitudes,which demonstrate remarkable consistency across measurements from both *** finding highlights clear uniformity in the mesospheric tidal patterns observed at low latitudes by the two neighboring meteor *** of the comparative analysis specifically underscore the significant correlation in vertical wavelength measurements,validating the robustness of radar observations for tidal research.

关键词： mesosphere and lower thermosphere region meteor radar mesospheric winds tides

Engineering high-performance chemiluminescent probes via enzymatic pocket targeting: high-throughput screening for ultralong afterglow imaging of orthotopic hepatocellular carcinoma

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年

作者： Shuai Huang Shuaige Bai Ting Luo Bin Feng min Liu Fan Zheng Shuang Huang Yanpeng Fang Dan Ding Wenbin zeng Xiangya School of Pharmaceutical Sciences Central South University College of Life Sciences Nankai University

Hepatocellular carcinoma （HCC） is a highly aggressive liver malignancy and the main form of liver cancer. Early diagnosis and treatment of HCC can effectively reduce mortality. Carboxylesterase （CE）-specific detection and imaging can be used for early diagnosis and image-guided surgical of HCC. However, traditional optical probes suffer from poor selectivity and low imaging signal-to-noise ratio. Here, we have constructed a series of chemiluminescent probes for carboxylesterase detection based on the strategy of enzymatic pocket-oriented steric tailoring techniques. The probes with different unique and excellent properties have been obtained through the structure-based steric hindrance adjustment on the recognition site. Here, CE-2 has been successfully used for high-throughput screening of rapid carboxylesterase inhibitors due to its extremely low detection limit (2.5×10-4U mL-1) and fast recognition ability. CE-3 has been successfully used for image-guided surgery of orthotopic hepatocellular carcinoma due to its ultra-long chemiluminescence imaging （over 12 h） of hepatocellular carcinoma. This study may promote advances in the rapid detection and screening of inhibitory drugs for CE and the field of surgical navigation in HCC.

关键词：