检索结果-南通市图书馆

Dynamic Response Analysis of Beams with Oblique Collision

在线全文

学校读者我要写书评

暂无评论

Engineering（科研） 2011年第7期3卷 786-794页

作者： Junping Pu Yandong chi 不详

Adopting a dynamic contact numerical method, some problems such as the central collision, transverse collision and oblique collision between two beams are researched. Numerical expressions for these cases are deduced. Using a self-developed finite element program some examples are computed, and compared with the analytical solution of the central collision, this numerical algorithm is proved to be reliable. For the other numerical results that have no analytical solution to be used to compare with, they are also reasonable through the theoretical analysis. For the transverse and oblique collision, the ideal results can be obtained by using a smaller time step.

关键词： Dynamic Contact Beam Oblique Collision Time-Variant Matrices

Immediate analgesic effect of needling acupoints(bilateral De Qi vs unilateral De Qi)on primary dysmenorrhea:a multi-center,randomized,controlled trail

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 Traditional chinese Medicine 2016年第6期36卷 711-717页

作者： Wang Pei Zhang Peng Ma Liangxiao Yuan Hongwen Liu Yuqi chi Lin Xin Siyuan Hu Nijuan Zhao Minyi Zhu Jiang School of Acupuncture Moxibustion and Tuina Beijing University of Chinese Medicine Beijing 100029 China School of Traditional chinese Medicine Capital Medical University Beijing 100069 China Department of chinese Medicine Beijing Tongren Hospital Affiliated to Capital Medical University Beijing 100730 China Institute of Basic Clinical Medicine China Academy of Traditional Chinese Medicine Beijing 100700 China Teaching and Research Section of Acupunc-ture-moxibustion and Tuina Chengde Medical CollegeChengde 067000 China

OBJECTIVE: To analyze the effect of needling acupoints(bilateral vs unilateral) with De Qi using data collected from 501 primary dysmenorrhea(PD) patients participating in multi-center, randomized,controlled ***: De Qi was defined as at least one of the feelings in soreness, numbness, fullness or heaviness at the acupoints when stimulated with needles. The 501 patients were grouped in 3 groups in terms of De Qi or not De Qi in one side(unilateral)or both sides(bilateral) of the body: bilateral De Qi group, unilateral De Qi group, and non-De Qi group. The abdominal pains were measured using visual analog scale(VAS).RESULTS: In 501 patients, 472 acquired De Qi at unilateral acupoints, 24 De Qi at bilateral acupoint,and 5 had no De Qi at any acupoint. The data of non-De Qi group was excluded as the sample was less than 5% of that in the bilateral De Qi *** was significant difference in the VAS before and after treatment between unilateral and bilateral De Qi group(P roup were larger than those in the unilateral De Qi group(P < 0.05).CONCLUSION: Bilateral De Qi was possibly superior to unilateral De Qi in enhancing the immediate analgesic effect of needling the acupoints, but no statistical significance was observed on the pa-tients of needling at non acupoint, which preliminarily suggested this immediate analgesic effect was perhaps along meridians.

关键词： Arrival of Qi Needling sensation Dysmenorrhea Visual analog scale Randomized controlled trail

Recent biomedical applications of bio-sourced materials

在线全文

学校读者我要写书评

暂无评论

Bio-Design and Manufacturing 2018年第1期1卷 26-44页

作者： Abdelrahman Elbaz Zhenzhu He Bingbing Gao Junjie chi Enben Su Dagan Zhang Songqin Liu Hua Xu Hong Liu Zhongze Gu State Key Laboratory of Bioelectronics School of Biological Science and Medical Engineering Southeast University Nanjing 210096 China Laboratory of Environment and Biosafety Research Institute of Southeast University in Suzhou S uzhou 215123 China Getein Biotech Inc. No. 9 Bofu Road Luhe District Nanjing 211505 Jiangsu China Jiangsu Engineering Laboratory of Smart Carbon-Rich Materials and Device Jiangsu Province Hi-Tech Key Laboratory for Bio-Medical Research School of Chemistry and Chemical Engineering Southeast University Nanjing 211189 China

Natural anisotropic nanostructures occurring in several organisms have gained more and more attention because of their obvious advantages in sensitivity, stability, security, miniaturization, portability, online use, and remote monitoring. Due to the development of research on nature-inspired bionic structures and the demand for highly efficient, low-cost microfabrication techniques, an understanding of and the ability to replicate the mechanism of structural coloration have become increasingly significant. These sophisticated structures have many unique functions and are used in many applications. Many sensors have been proposed based on their novel structures and unique optical properties. Several of these bio-inspired sensors have been used for infrared radiation/thermal, pH, and vapor techniques, among others, and have been discussed in detail, with an intense focus on several biomedical applications. However, many applications have yet to be discovered. In this review, we will describe these nanostructured materials based on their sources in nature and various structures, such as layered, hierarchical, and helical structures. In addition, we discuss the functions endowed by these structures, such as superhydrophobicity, adhesion, and high strength, enabling them to be employed in a number of applications in biomedical fields, including cell cultivation, biosensors, and tissue engineering.

关键词： Nature Bio-sourced Bio-inspired Bio-Materials Biomedical

Typical faults and safety analysis of brake controller for AC locomotive

在线全文

学校读者我要写书评

暂无评论

Railway Sciences 2023年第4期2卷 486-494页

作者： Yujie Ren Hai chi Brake Technology Development Department Beijing Zongheng Electro-Mechanical Technology Co.LtdBeijingChina Locomotive and Car Research Institute China Academy of Railway Sciences Corporation LimitedBeijingChina

Purpose–The brake controller is a key component of the locomotive brake *** is essential to study its ***/methodology/approach–This paper summarizes and analyzes typical faults of the brake controller,and proposes four categories of faults:position sensor faults,microswitch faults,mechanical faults and communication *** and methods for impro.ing the safety of the brake controller are also ***–In this paper,a self-judgment and self-learning dynamic calibration method is proposed,which integrates the linear error of the sensor and the manufacturing and assembly errors of the brake controller to solve the output *** paper also proposes a logic for diagnosing and handling microswitch *** are proposed for other faults of brake ***/value–The methods proposed in this paper can greatly improve the usability of the brake controller and reduce the failure rate.

关键词： Locomotive brake system Brake controller Faults

Reactivity,Regioselectivity,and Synthetic Application of 2-Pyrenyl Units in Scholl Reactions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CCS Chemistry 2023年第9期5卷 2069-2077页

作者： Sai Ho Pun Ethan chi Ho Wen Zeming Xia Han Chen Felix RFischer Qian Miao Department of Chemistry The Chinese University of Hong KongHong Kong Department of Chemistry University of CologneCologne Department of Chemistry University of CaliforniaBerkeleyCalifornia 94720 Materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCalifornia 94720 Kavli Energy NanoScience Institute at the University of California Berkeley and the Lawrence Berkeley National Laboratory BerkeleyCalifornia 94720 Bakar Institute of Digital Materials for the Planet Division of ComputingData Scienceand SocietyUniversity of CaliforniaBerkeleyCalifornia 94720

We herein report the reactivity and regioselectivity of 2-pyrenyl as a coupling unit in Scholl *** the basis of the Scholl reactions of hexaarylbenzene substrates,we have found that pyrenyl units are preferably oxidized over naphthyl and phenyl units under appropriate Scholl reaction conditions,allowing divergent synthesis through a highly controllable intramolecular coupling *** find that the C1 and C3 positions of the 2-pyrenyl unit are the favorable sites for intramolecular coupling while C4 is not reactive to allow further *** reactivity and regioselectivity pattern can be explained by the spin density distribution,which shows that carbon-carbon bonds preferably form at sites with higher positive spin *** by these findings,we successfully synthesized a double helicene and a sextuple helicene through the controlled Scholl reactions of 2-pyrenyl units.

关键词： helicene polycyclic aromatics pyrene Scholl reactions spin density

ESP course design： An intensive, non-assessed, in-service oral business English course for intermediate business people

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Sino-US English Teaching 2008年第8期5卷 13-17页

作者： chi Gui-min School of Foreign Languages Guangdong University of Technology Guangzhou 510520 China

With the great impact of WTO and the business globalization, professional internationalized business people are heavily demanding, which imposes pressure and necessity on practical and effective Business English program. This essay intends to design an intensive, non-assessed, inservice oral business English course for intermediate business people.

关键词： ESP(English for Specific Purposes) business English course design need analysis syllabus

The effect of Fe-Mn minerals and seawater interface and enrich-ment mechanism of ore-forming elements of polymetallic crusts and nodules from the South china Sea

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2017年第6期36卷 34-46页

作者： GUAN Yao SUN Xiaoming IANG Xiaodong SA Rina ZHOU Li HUANG Yi LIU Yating LI Xiaojie LU rongfei WANG chi School of Marine Sciences Sun Yat-sen UniversityGuangzhou 510006China Guangdong Pro.incial Key Laboratory of Marine Resources and Coastal Engineering Guangzhou 510006China School of Earth Sciences and Geological Engineering Sun Yat-sen UniversityGuangzhou 510275China State Key Laboratory for Mineral Deposits Research Nanjing UniversityNanjing 210046China

Ferromanganese crusts and nodules are important submarine mineral resources that contain various metal elements with significant economic value. In this study, polymetallic crusts and nodules obtained from the South china Sea （SCS） were determined by using X-ray power diffraction （XRD）, Raman spectroscopy （RS）, Fourier transform infrared spectroscopy （FTIR）, and X-ray photoelectron spectroscopy （XPS） to systematically investigate and analyze the mineralogical and spectral characteristics of the Fe-Mn minerals. XRD measurements revealed that the SCS polymetallic crusts and nodules were composed of vernadite, quartz, and plagioclase. The nodules also contained todorokite. The Fe-phase minerals of the SCS crusts and nodules were composed of amorphous Fe oxide/hydroxide, and the Mn- and Fe-phases minerals exhibited relatively poor degrees of crystallization. FTIR results showed that the Fe-Mn minerals in the crusts and nodules included a large number of surface hydroxyl groups. These surface hydroxyl groups contained protons that could provide reactive sites for complexation of ore-forming elements in seawater. XPS results indicated that the surfaces of the Fe-Mn minerals mainly contained Fe, Mn, and O. Fe was present in the trivalent oxidation state, while Mn, which may contain several bivalent oxidation state, was present in the tetravalent and trivalent oxidation states. The SCS polymetallic crusts and nodules were compared with Pacific seamount crusts, and results showed that the surface hydroxyl （-OH） groups of the SCS crusts and nodules numbered more than the lattice oxygen （O^2-）. But the lattice oxygen of Pacific seamount crusts numbered more than the surface hydroxyl groups. This characteristic indicated that the degree of crystallization of Fe-Mn minerals from the Pacific Ocean was higher than that of minerals from the South china Sea. Comprehensive studies showed that ore-forming elements in the interface between seawater and the Fe-Mn minerals in the submari

关键词： polymetallic crust and nodule mineralogy characteristic interface effect element enrichment surfacecomplexation

Design,Synthesis,and Biological Evaluation of 5H-Thiazolo[3,2-a]pyrimidine-6-carboxylic Acid Ethyl Ester Derivatives as a Novel Series of Acetylcholinesterase Inhibitors

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3期25卷 332-337页

作者： ZHI Hui CHEN Lan-mei ZHANG Lin-lin LIU Si-jie David chi Cheong WAN LIN Huang-quan HU Chun School of Pharmaceutical Engineering Shenyang Pharmaceutical University Shenyang 110016 P. R. China Department of Biochemistry The Chinese University of Hong Kong Hong Kong SAR P. R. China

Acetylcholinesterase inhibitors are the most frequently prescribed anti-Alzheimer＇s drugs. A series of 5H-thiazolo[3,2-a]pyrimidine-6-carboxylic acid ethyl ester derivatives as the novel acetylcholinesterase inhibitors was designed based on virtual screening methods. The target compounds were synthesized with Biginelli reaction and Hantzsch-type condensation of dihydropyrimidines with substituted phenacyl chlorides, and were characterized with elemental analysis, IR, MS, ^1H NMR, and ^13C NMR. The biological evaluation against human acetylcholinesterase in vitro.indicated all the target compounds show more than 50% inhibition at 10μmol/L by means of the Ellman method. The results provide a starting point for the development of novel drugs to treat Alzheimer＇s disease and lay the foundation of searching for improved acetylcholinesterase inhibitors with the novel scaffolds.

关键词： Acetylcholinesterase inhibitor Docking screening Heterocycle Biological activity 5H-Thiazolo[3,2-a] pyrimidine-6-carboxylic acid ethyl ester derivative

美味猕猴桃MYB家族鉴定及其对水淹胁迫的响应

在线全文

学校读者我要写书评

暂无评论

湖北农业科学 2024年第5期63卷 215-222页

作者：乐有章王建军戢小梅迟文超林之希武汉市农业科学院武汉430075 南京农业大学园艺学院南京210095

基于美味猕猴桃(Actinidia deliciosa)二代转录组测序数据,通过多种生物信息学手段鉴定和分析了AcMYB家族基因。结果表明,在美味猕猴桃转录组数据中共获得64个具有完整ORF序列的AcMYB家族成员,将其分成4个亚族,其中亚族Ⅰ共34个成员,亚... 详细信息

基于美味猕猴桃(Actinidia deliciosa)二代转录组测序数据,通过多种生物信息学手段鉴定和分析了AcMYB家族基因。结果表明,在美味猕猴桃转录组数据中共获得64个具有完整ORF序列的AcMYB家族成员,将其分成4个亚族,其中亚族Ⅰ共34个成员,亚族Ⅱ共18个成员,亚族Ⅲ共10个成员,亚族Ⅳ共2个成员。水淹处理前后表达分析显示,AcMYB_214187、AcMYB_25788等AcMYB成员美味猕猴桃根中的表达水平明显降低,快速响应水淹胁迫,而叶中的表达水平差异不明显。AcMYB_19450、AcMYB_30021等AcMYB成员根中的表达水平差异不明显,但叶中的表达水平明显降低,可能原因是根接收到低氧胁迫信号后,将其传递到地上部并发挥作用,通过转录水平调控美味猕猴桃对低氧胁迫的响应。研究结果为后续开展美味猕猴桃MYB转录因子研究、促进抗逆境育种、提高产量提供了依据。

关键词：美味猕猴桃(Actinidia deliciosa) AcMYB 鉴定水淹胁迫响应

维普期刊数据库博看期刊