检索结果-南通市图书馆

Multi-channel phasemeter and its application in the heterodyne laser interferometry

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2015年第4期58卷 746-749页

作者： liU He Shan DONG yu Hui LUO Zi Ren li yu qiong JIN Gang National Microgravity Laboratory (NML) Institute of Mechanics Chinese Academy of Sciences School of Physics Chinese Academy of Sciences

The mission to detect gravitational wave in space requires a not only sophisticated but also ultra-precise laser interferometric measurement system. Within a single spacecraft, tens of interferometric beat signals are generated at the same time and they also need to be processed simultaneously. In this paper, a multi-channel phasemeter which can parallelly process the signals is constructed. The test shows that a sensitivity of 2n grad/√Hz could be achieved in the frequency range of 0.1 to 10 Hz. We also utilize the phasemeter to evaluate the performance of a heterodyne laser interferometer.

关键词： phasemeter laser interferometer gravitational waves detection

在线全文

学校读者我要写书评

暂无评论

宁夏地区奶牛源隐孢子虫分子鉴定与分析

动物医学进展 2024年第4期45卷 130-136页

作者：黎玉琼于有利从志鹏赵正伟梁小军王韦健李继东李勤凡文亮牛晓昊宁夏农林科学院宁夏银川750002 西北农林科技大学陕西杨凌712100 华南农业大学广东广州510642 宁夏大学宁夏银川750002 宁夏农垦乳业股份有限公司渠口牧场宁夏银川750002

为了明确宁夏地区奶牛隐孢子虫的流行情况及其优势基因型,采集宁夏4个地区10个规模化奶牛养殖场中1174份奶牛粪便样品,基于核糖体小亚基RNA(SSU rRNA)基因通过套式PCR进行检测和分析。结果显示,宁夏地区奶牛隐孢子虫阳性率为28.5%(335/1... 详细信息

为了明确宁夏地区奶牛隐孢子虫的流行情况及其优势基因型,采集宁夏4个地区10个规模化奶牛养殖场中1174份奶牛粪便样品,基于核糖体小亚基RNA(SSU rRNA)基因通过套式PCR进行检测和分析。结果显示,宁夏地区奶牛隐孢子虫阳性率为28.5%(335/1174);共鉴定出4种虫种,即微小隐孢子虫、牛隐孢子虫、瑞氏隐孢子虫和安氏隐孢子虫,阳性率分别为40.6%(136/335)、36.1%(121/335)、19.4%(65/335)和3.9%(13/335);微小隐孢子虫共鉴定出4种基因亚型,分别为ⅡdA15G1(n=70)、ⅡdA18G1(n=26)、ⅡdA19G1(n=23)和ⅡdA20G1(n=17)。统计学分析显示,在宁夏地区,0~2月龄的犊牛隐孢子虫感染率最高,且奶牛隐孢子虫的感染率与月龄差异显著相关(P<0.001)。表明宁夏地区奶牛存在隐孢子虫感染且存在人畜共患虫种,ⅡdA15G1微小隐孢子虫是宁夏地区奶牛感染的优势亚型。

关键词：隐孢子虫微小隐孢子虫 SSU rRNA基因套式PCR 阳性率

Preparation, Structure and Properties of 3D Supramolecular Architecture, on the Basis of Hydrogen Bonds and π-π Stacking Between 2D Layers, with Windmill Building Blocks

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2008年第3期24卷 251-254页

作者： yu li-qiong HUANG Ru-dan CHI Ying-nan HU Chang-wen Department of Chemistry Beijing Institute of Technology Beijing 100081 P R. China

A novel three-dimensional（3D） supramolecular architecture, {[Nd（OH-BDC）（OH-HBDC）（H2O）2]·2HaO）n（1）（OH-H2BDC=5-hydroxyisophthalic acid）, which was formed through hydrogen bonds and π-π stacking between two-dimensional（2D） layers, was hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Windmill building blocks, which consist of two nine-coordinated metal centers and four OH-H2BDC groups are connected through two carboxyl groups, to lead to a one-dimensional infinite inorganic chain（… M--O--C--O--M…） along the [100] direction. An observed intense blue luminescence with an emission band peaked at 390 nm for compound 1 may results from ligand-to-metal charge transfer（LMCT）. Variable-temperature magnetic susceptibility of compound 1 was investigated and the value was deviated from the Curie-Weiss law.

关键词： Building block π-π stacking Hydrogen bond Luminescence Magnetism

Laser Interferometer Used for Satellite-Satellite Tracking: an On-Ground Methodological Demonstration

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2012年第7期29卷 295-297页

作者： li yu-qiong LUO Zi-Ren liU He-Shan DONG yu-Hui JIN Gang National Microgravity Laboratory(NML) Institute of MechanicsChinese Academy of SciencesBeijing 100190

A Chinese satellite gravity mission called SAGM (Space Advanced Gravity Measurements) is now taken into *** meet its designed requirement,the measurement precision of the laser ranging system used to measure the inter-satellite distance change has to be better than l00nm/Hz1/2 within a broad bandwidth from 0.1mHz to *** equal arm heterodyne Mach-Zehnder interferometer has been built on ground to demonstrate the measurement principle of a laser ranging system,which potentially can be used for both SAGM and future GW (gravitational wave) space *** of the equal arm length,the laser frequency noise has been significantly suppressed in the ***,the sensitivity better than 1nm/Hz1/2 in a frequency range of 0.15 mHz-0.375 Hz has been *** result shows that the proposed methodology has very promising feasibility to meet the requirements of SAGM and of GW space antennas as well.

关键词： interferometer antennas heterodyne

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

浅析生乳滋气味管控

中国奶牛 2024年第2期 7-11页

作者：于有利黎玉琼时发亿陈松睿从志鹏宁夏农林科学院银川750002 固原市职业技术学校固原756000 西北农林科技大学杨凌712000

本文以生乳的气味为主要研究对象。通过对奶牛场生产过程中数据的研究和分析,对奶牛场的整个生产过程进行跟踪,检测出异常气味牛奶中的差异代谢产物。目的是阐明牛奶异味的概念、原因和解决方案,从而为减少乳制品生产中异常奶味和异味... 详细信息

本文以生乳的气味为主要研究对象。通过对奶牛场生产过程中数据的研究和分析,对奶牛场的整个生产过程进行跟踪,检测出异常气味牛奶中的差异代谢产物。目的是阐明牛奶异味的概念、原因和解决方案,从而为减少乳制品生产中异常奶味和异味的发生提供依据。

关键词：生乳滋气味产生原因预防解决方案

Design and Self-assembly of a Novel Tetranuclear Zinc(Ⅱ) Complex via Reaction of 1,3-Thiazolidine-2-thione(tzdtH) with Zn(NO_ 3)_ 2

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2006年第5期22卷 665-668页

作者： WEI Xian-yin HUANG Ru-dan yu li-qiong ZHU Qin-lei ZHANG Zhong-qiang liU li-ping Department of Chemistry School of Science Beijing Institute of Technology Beijing 100081 P. R. China Department of Chemistry Hengshui University Hengshui 053000 P. R. China

The self-assembly of clusters in inorganic systems is an interesting subject. The self-assembly of big molecules has been well established in biological systems. In addition, the coordination chemistry of metal-sulfur-nitrogen cluster complexes has been a very active and attracting field for many years as a result of the novelty and versatility of the crystal structures and reactivities of such clusters, as well as their potential applications as the models for the active sites in non-heme proteins. At the same time, there is currently considerable interest in the formation of metal complexes with heterocyclic ligands because of the diverse characteristics of ligands and their consequential wide range of applications.

关键词： Self assembly Tetranuclear cluster Zinc complex Crystal structure

Integration of urchin-like MnCo_(2)O_(4)@C core–shell nanowire arrays within porous copper current collector for superior performance li-ion battery anodes

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第2期43卷 599-611页

作者： Xue-Ru Zhang qiong Wu Yong Zhang Xi-Fei li Ting Xie yu-Cheng Wu Instrumental Analysis Center Hefei University of TechnologyHefei230009China Key Laboratory of Advanced Functional Materials and Devices of Anhui Province Hefei230009China School of Materials Science and Engineering Hefei University of TechnologyHefei230009China Institute of Advanced Electrochemical Energy Xi’an University of TechnologyXi’an710048China

Spinel MnCo_(2)O_(4) is a promising energy storage candidate as anode materials in lithium-ion batteries owing to synergistic effects of two intrinsic solid-state redox ***,low conductivity,poor rate capacity and rapid capacity fading have seriously impaired its practical *** overcome the inferiorities,urchin-like MnCo_(2)O_(4)@C core–shell nanowire arrays have been fabricated directly within a porous copper current collector via a facile hydrothermal method followed by a chemical vapor deposition carbonization *** a typical nanowire,the core is composed of interconnected MnCo_(2)O_(4)nanoparticles and the shell shows as a thin amorphous carbon *** integrated MnCo_(2)O_(4)@C/Cu structure could act as working anodes without using additives or polymer *** MnCo_(2)O_(4)@C/Cu possesses slightly longer li-ion insertion/desertion pathway than that of MnCo_(2)O_(4)/Cu,the carbon shell could effectively prevent the pulverization of MnCo_(2)O_(4) and lower down charge transfer resistance and actively participate in li-ion *** rearrangement of carbon atoms during lithiation/delithiation cycling could inhibit the formation of passive solid electrolyte interphase *** a result,the MnCo_(2)O_(4)@C/Cu electrode presents superior rate capacity(600 mAh·g^(−1) at 1 A·g^(−1)) and better stability(797 mAh·g^(−1) after 200 cycles at 100 mA·g^(−1)).The excellent reversible li ion storage capacity,cycling stability and rate capacity endow MnCo_(2)O_(4)@C/Cu great potential as stable and high output integrated anode materials in li-ion batteries.

关键词： MnCo_(2)O_(4)@C Urchin-like nanowire arrays Core-shell Integrated anode materials lithium-ion batteries

The MtRGF6 Peptide Differentially Regulates Root Development and Symbiotic Nodulation of Medicago truncatula and Lotus japonicus

在线全文

学校读者我要写书评

暂无评论

Phyton-International Journal of Experimental Botany 2024年第6期93卷 1237-1248页

作者： Junhui Yan Yawen Wang qiong li yu Zhou Xu Wang li Luo School of life Sciences Shanghai Key Laboratory of Bio-Energy CropsShanghai UniversityShanghai200444China College of life Science State Key Laboratory of Tea Plant Biology and UtilizationAnhui Agricultural UniversityHefei230036China

Rhizobia induces nitrogen-ﬁxing nodules in legumes used in agricultural production,providing a direct source of combined nitrogen to leguminous *** peptides,such as CLAVATA3/EMBRYO SURROUNDING REGION peptides(CLE),are known to regulate the formation and development of nitrogen-ﬁxing nodules in *** meristem growth factor(RGF)peptides from Medicago truncatula not only regulate root develop-ment but also modulate nodulation symbiosis with Sinorhizobium ***,the impact of RGF peptides from one leguminous species on the others remains *** this study,we investigate the effects of the RGF family peptide MtRGF6p from *** on nodulation symbiosis and root development in Lotus *** MtRGF6 gene is predominantly expressed in the root nodules of *** and shows low identity with RGF homologous genes from *** gene promoter is active in the primordia of root nodules and lat-eral roots,as well as in young nodules and roots,and the meristem,infection,and nitrogen-ﬁxing regions of the mature *** synthesized MtRGF6p promoted primary root growth in *** but sup-pressed the growth of *** primary *** peptide negatively affected the initiation of nodule primor-dia,the formation of infection threads,and nodulation in both legumes,with a low dosage showing effects on *** compared to *** results suggest that the MtRGF6 peptide from *** may serve as an inter-species signal affecting the root organ development of ***.

关键词： Peptide RGF legume symbiotic nodulation lateral root

Simulation study on the security of consensus algorithms in DAG-based distributed ledger

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 Computer Science 2024年第3期18卷 171-182页

作者： Shuzhe li Hongwei XU qiong li Qi HAN Faculty of Computing Harbin Institute of TechnologyHarbin 150001China

Due to the advantages of high volume of transactions and low resource consumption,Directed Acyclic Graph(DAG)-based Distributed Ledger Technology(DLT)has been considered a possible next-generation alternative to ***,the security of the DAG-based system has yet to be comprehensively *** at verifying and evaluating the security of DAG-based DLT,we develop a Multi-Agent based IOTA Simulation platform called *** MAIOTASim,we model honest and malicious nodes and simulate the configurable network environment,including network topology and *** double-spending attack is a particular security issue related to *** perform the security verification of the consensus algorithms under multiple double-spending attack *** simulations show that the consensus algorithms can resist the parasite chain attack and partially resist the splitting attack,but they are ineffective under the large weight *** take the cumulative weight difference of transactions as the evaluation criterion and analyze the effect of different consensus algorithms with parameters under each attack ***,MAIOTASim enables users to perform largescale simulations with multiple nodes and tens of thousands of transactions more efficiently than state-of-the-art ones.

关键词： distributed ledger IOTA Multi-Agent system simulation