检索结果-南通市图书馆

Ionic Liquids-Assisted Highly Luminescent Copper Nanoclusters with Triangle Supramolecular Nanostructures

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2021年第7期39卷 1867-1870页

作者： Bingyan Han Qin yan.ze Xin Qifang yan Jingmei Jiang State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalianLiaoning116023 China School of Chemical Engineering Dalian University of TechnologyPanjinLiaoning124221 China

Main observation and conclusion A novel and facile approach towards highly luminescent CuNCs@MMI(2-mercapto-1-methylimidazole)has been developed within 30 s with the assistance of ionic liquids(ILs)-[Bmim]BF_(4).FT-IR... 详细信息

关键词： Nanostructures Ionic liquids Aggregation Surface analysis [Bmim]BF_(4)

Structural and Electrical Characteristics of Amorphous ErAlO Gate Dielectric Films

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

Chinese Physics Letters 2012年第8期29卷 244-246页

作者： ZHU yan-yan FANG ze-Bo TAN Yong-Sheng Department of Physics Shaoxing UniversityShaoxing 312000 Department of Mathematics and Physics Shanghai University of Electric PowerShanghai 200090

Ultrathin high-k dielectric ErAlO films were deposited on Si(100)substrates by using radio-frequency magnetron *** very flat surface of the annealed film with a rms roughness less than 0.25 nm was observed by using an atomic force *** film shows good thermal stability when annealing at 900℃ for 30 s in the O_(2) *** effective dielectric constant of the film is around 15.2,and a low leakage current of 8.4×10^(-5) A/cm^(2) at an electric field of 1 MV/cm was achieved for the film with the equivalent oxide thickness of 2.0 nm after annealing.

关键词： film roughness annealed

Evaluation of D（d,n）^3 He reaction neutron source models for BNCT irradiation system design

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

Nuclear Science and Techniques 2007年第6期18卷 330-335页

作者： YAO ze＇en LUO peng Tooru KOBAYASHI Gerard BENGUA School of NuclearScience and Technology Lanzhou University Lanzhou 730000 China Research Reactor Institute Kyoto University Osaka 590-0494 Japan

A mathematical method was developed to calculate the yield,energy spectrum and angular distribution of neutrons from D(d,n)~3He(D-D)reaction in a thick deuterium-titanium target for incident deuterons in energies lower than *** data of energy spectrum and angular distribution were applied to set up the neutron source model for the beam-shaping-assembly(BSA)design of Boron-Neutron-Capture-Therapy(BNCT)using MCNP-4C code. Three cases of D-D neutron source corresponding to incident deuteron energy of 1000,400 and 150 key were inves- *** neutron beam characteristics were compared with the model of a 2.45 MeV mono-energetic and isotropic neutron source using an example BSA designed for BNCT *** results show significant differences in the neutron beam characteristics,particularly the fast neutron component and fast neutron dose in air,between the non-isotropic neutron source model and the 2.5 MeV mono-euergetic and isotropic neutron source model.

关键词：中子源反作用力中子能量放射

Monitoring nearest neighbor queries with cache strategies

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 529-537页

作者： PAN peng LU yan-sheng College of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

The problem of continuously monitoring multiple K-nearest neighbor (K-NN) queries with dynamic object and query dataset is valuable for many location-based applications. A practical method is to partition the data space into grid cells, with both object and query table being indexed by this grid structure, while solving the problem by periodically joining cells of objects with queries having their influence regions intersecting the cells. In the worst case, all cells of objects will be accessed once. Object and query cache strategies are proposed to further reduce the I/O cost. With object cache strategy, queries remaining static in current processing cycle seldom need I/O cost, they can be returned quickly. The main I/O cost comes from moving queries, the query cache strategy is used to restrict their search-regions, which uses current results of queries in the main memory buffer. The queries can share not only the accessing of object pages, but also their influence regions. Theoretical analysis of the expected I/O cost is presented, with the I/O cost being about 40% that of the SEA-CNN method in the experiment results.

关键词： K-nearest neighbors (K-NNs) Continuous query Object cache Query cache

Specific Expression of Maize SBEIIb Promoter Mediated by Different Promoter Region in Transgenic Tobacco Plants

在线全文

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2009年第11期8卷 1277-1285页

作者： SUN Cui-xia HAN Jing LI Meng WANG Xiao-peng ZHANG Guo-dong TIAN yan-chen WANG ze-li National Key Laboratory of Crop Biology College of Life Sciences Shandong Agricultural University Tai 'an 271018 P.R. China Maize Research Institute Shandong Academy of Agricultural Sciences Jinan 250000 P.R. China

Starch branching enzyme （SBE） catalyzes the biosynthesis of amylopectin. We described the isolation and characterization of SBEIIb promoter and their expression patterns in transgenic tobacco. Using the genomic DNA of maize cultivar Lunuo 1 as template, the SBEIIb promoter was isolated by PCR and was cloned into pMD18-T vector. To study SEBIIb gene regulation at the cellular level, SBEIIb promoter was fused to the ^-glucuronidase （GUS） report gene. The results of the fluorometric GUS assays indicate that the sbeⅡb-GUS fusion directed a seed-specific expression. Four series of constructs were made with the promoter and the GUS reporter gene to investigate the cis-acting analysis, showing that the four different constructs all can drive expression of the GUS gene in seed plumule and cotyledon and the GUS activity was apparently decreased with the progressive loss of promoter 5＇ end.

关键词： maize starch-branching enzyme promoter cloning specific expression

Regulation of the Arabidopsis GSK3-like Kinase BRASSINOSTEROID-INSENSITIVE 2 through Proteasome-Mediated Protein Degradation

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2008年第2期1卷 338-346页

作者： peng peng Zhenyan yan Yongyou Zhu Jianming Li Department of Molecular Cellular and Development Biology University of Michigan Ann Arbor MI 48109-1048 USA Present address: Howard Hughes Medical Institute Department of Molecular Cell and Developmental Biology University of California-Los AngelesLos Angeles CA g0095 USA

Glycogen synthase kinase 3 （GSK3） is a unique serine/threonine kinase that is implicated in a variety of cellular processes and is regulated by phosphorylation or protein-protein interaction in animal cells. BIN2 is an Arabidopsis GSK3- like kinase that negatively regulates brassinosteroid （BR） signaling. Genetic studies suggested that BIN2 is inhibited in response to BR perception at the cell surface to relieve its inhibitory effects on downstream targets; however, little is known about biochemical mechanisms of its inhibition. Here, we show that BIN2 is regulated by proteasome-mediated protein degradation. Exogenous application of a BR biosynthesis inhibitor and an active BR increased and decreased the amount of BIN2 proteins, respectively. Interestingly, the gain-of-function bin2-1 mutation significantly stabilizes BIN2, making it unresponsive to BR-induced BIN2 depletion. Exogenous application of different plant growth hormones revealed that BIN2 depletion is specifically induced by BR through a functional BR receptor, while treatment of a protea- some inhibitor, MG132, not only prevented the BR-induced BIN2 depletion but also nullified the inhibitory effect of BR on the BIN2 kinase activity. Taken together, our results strongly suggest that proteasome-mediated protein degradation constitutes an important regulatory mechanism for restricting the BIN2 activity.

关键词： .Regulates brassinosteroid BR signaling Arabidopsis GSK BR receptor

A beam flexure-based nanopositioning stage supporting laser direct-write nanofabrication

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

Science China(Physics,Mechanics & Astronomy) 2016年第8期59卷 50-55页

作者： Zhen Zhang peng Wang peng yan YingChun Guan State Key Laboratory of Tribology and Institute of Manufacturing Engineering Department of Mechanical EngineeringTsinghua University Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Tsinghua University State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University Key Laboratory of High-efficiency and Clean Mechanical Manufacture Ministry of Education School of Mechanical EngineeringShandong University School of Automation Science and Electrical Engineering Beihang University School of Mechanical Engineering and Automation Beihang University

A nanopositioning system of both millimetric stroke and nanometric tracking accuracy is a key component for nanofabrication in many applications. In this paper, a novel bi-axial beam-flexure nano servo stage is proposed to support a direct writing system for femtosecond laser nanofabrication. The important features of the stage lie in: a mirror symmetric instead of rotational symmetric configuration is adopted to restrict cross axis coupling, and a novel Z-shaped guidance module is proposed to achieve relative large linear stiffness range, in addition a redundant constraints module is introduced to increase off-axis stiffness of the stage. Mechanical analysis and system identification are provided, with which a feedback control algorithm demonstrates the tracking capability for laser fabrication purposes. Based on the fabricated XY nano-stage, real time control and measurements are deployed, demonstrating the millimetric operating workspace and 77.8 nm(RMS) error of tracking a circular trajectory.

关键词： laser nanofabrication direct writing servo and control system

Synthesis of polynorbornene with pendant moiety bearing azide and terminal alkyne groups

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第7期22卷 785-788页

作者： ze Zhang Zhi Wei peng Kun zeng Fan School of Biochemical Engineering Anhui Polytechnic University Wuhu 241000 China Department of Chemistry University of Science and Technology of China Hefei 230026 China

A powerful approach to the synthesis of an unprecedented polynorbornene with pendant moiety bearing azide and terminal alkyne groups is developed. Two key intermediates, namely, 3-azido-5-（2-（trimethylsilyl）ethynyl） benzyl alcohol and 4-（4-azatricyclo [5.***.1.0^2.6]dec-8-en-4-yl） benzoic acid, were optimally synthesized for convergent synthesis of the corresponding monomer.

关键词： Polynorbomene Azide Alkyne Esterification Metathesis

SN 1054: A pulsar-powered supernova?

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2015年第11期15卷 1823-1831页

作者： Shao-ze Li Yun-Wei Yu yan Huang Institute of Astrophysics Central China Normal University

The famous ancient supernova SN 1054 could have been too bright to be explained in the “standard” radioactive-powered supernova scenario. As an alternative attempt, we demonstrate that the spin-down of the newly born Crab pulsar could provide a sufficient energy supply to make SN 1054 visible at daytime for 23 days and at night for 653 days, where a one-zone semi-analytical model is employed. Our results indicate that SN 1054 could be a “normal” cousin of magnetar-powered superluminous supernovae. Therefore, SN 1054-like supernovae could be a probe to uncover the properties of newly born neutron stars, which provide initial conditions for studies on neutron star evolutions.

关键词： scenario powered neutron gamma bright ancient luminosity attempt radioactive stars