检索结果-南通市图书馆

灌溉排水学报 2004年第2期23卷 6-12,25页

作者：许迪李益农刘钰蔡林根 J M Gonalves l s Pereira 国家节水灌溉北京工程技术研究中心北京100044 葡萄牙里斯本科技大学农学院

应用具有决策支持系统(Dss)功能的sEDAM模型模拟黄河下游簸箕李引黄灌区的灌溉需求与渠系输配水状况,利用节水多准则分析方法评价农田与输配水系统的改善方案。以田间实测的各类典型数据资料为基础,采用随机方法生成与田间和各级渠道相... 详细信息

应用具有决策支持系统(Dss)功能的sEDAM模型模拟黄河下游簸箕李引黄灌区的灌溉需求与渠系输配水状况,利用节水多准则分析方法评价农田与输配水系统的改善方案。以田间实测的各类典型数据资料为基础,采用随机方法生成与田间和各级渠道相关的数据,产生用于多准则分析的属性数据和性能指标。根据不同水平的与农田及输配水系统相关的决策变量,设计了8种用于改善农田与输配水系统的模拟方案,通过模拟的需水量与现状供水量之间的对比以及模拟的各类效用值随时间变化的趋势,对模拟结果进行分析。结果表明,采用改善的农田与输配水系统运行方案可有效地减少渠系渗漏量,较好地控制农田渗漏损失,利用田间径流排水作为补灌水源,达到节水增产、改善农田生态环境的目的。

关键词：农田输配水系统节水多准则分析决策支持系统 Dss

ATRANsMIssION ElECTRONIC MICROsCOPY sTUDY ONFORMATION AND MICROsTRUCTURE CHANGE OF Mg2Ni DURING MECHANICAl AllOYING

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica sinica(English letters) 1999年第4期12卷 415-420页

作者： s.J.Ji,Z.W.Yu ,J.C.sun ,Z.K.Hei and l.Yan Institute of Metaland Technology,Dalian Maritime University ,Dalian 116026 ,China

The microstructuralchangeof mechanicalalloyingof pureelemental Mg Nipowders wasin vestigated by transmission electronic microscopy ( TEM). The experimental results showed thatafter5 h milling, Mg2 Ni phase precipitated mainly from Mg grain , and no Mg2 Ni wasfound in Ni matrix. Thiscan be attributed tothe asym metricalinterdiffusion between Mg and Ni atom , which causesthecontent of Mg in Ni grain far below thestoichiometric composition of Mg2 Ni. After the growth of Mg2 Ni grain, the severe mechanical deforma tion resulting from mechanicalalloying led tothetransformation of Mg2 Ni from hexagonal tofccstructure partially, which makes Mg2 Ni grain in a composite microstructure fcc + hcp.

关键词： Mg2 Ni mechanicalalloying,fcctransformation

High resolution scanning gate microscopy measurements on InAs/Gasb nanowire Esaki diode devices

在线全文

学校读者我要写书评

暂无评论

Nano Research 2014年第6期7卷 877-887页

作者： James l. Webb Olof Perssor Kimberly A. Dick Claes Thelander Rainer Timm Anders Mikkelsen Division of synchrotron Radiation Research Lund University Sweden Center forAnalysis and synthesis Lund University Sweden Division of solid state Physics Lund University Sweden

Gated transport measurements are the backbone of electrical characterization of nanoscale electronic devices. scanning gate microscopy （sGM） is one such gating technique that adds crucial spatial information, accessing the localized properties of semiconductor devices. Nanowires represent a central device concept due to the potential to combine very different materials. However, sGM on semiconductor nanowires has been limited to a resolution in the 50-100 nm range. Here, we present a study by sGM of newly developed III-V semiconductor nanowire InAs/Gasb heterojunction Esaki tunnel diode devices under ultra-high vacuum. sub-5 nm resolution is demonstrated at room temperature via use of quartz resonator atomic force microscopy sensors, with the capability to resolve InAs nanowire facets, the InAs/Gasb tunnel diode transition and nanoscale defects on the device. We demonstrate that such measurements can rapidly give important insight into the device properties via use of a simplified physical model, without the requirement for extensive calculation of the electrostatics of the system. Interestingly, by precise spatial correlation of the device electrical transport properties and surface structure we show the position and existence of a very abrupt （〈10 nm） electrical transition across the InAs/Gasb junction despite the change in material composition occurring only over 30-50 nm. The direct and simultaneous link between nanostructure composition and electrical properties helps set important limits for the precision in structural control needed to achieve desired device performance.

关键词： nanowire,scanning gate microscopy Esaki tunnel diode,InAs,Gasb,III-V,heterostructure

重度子痫前期患者胎盘组织中CD44 mRNA和CD24 mRNA及蛋白表达水平的临床价值研究

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

现代检验医学杂志 2024年第1期39卷 43-48页

作者：滕玲玲马广贞石可吕颖欣徐静聊城市第二人民医院产科山东临清252601 聊城市第二人民医院病理科山东临清252601 河北医科大学第一医院产科石家庄050000

目的探讨重度子痫前期(severe preeclampsia,sPE)患者胎盘中细胞表面跨膜糖蛋白分子(cell surface transmembrane glycoprotein molecules,CD)44 mRNA,细胞表面跨膜糖蛋白分子24(CD24)mRNA及蛋白表达水平表达的临床价值研究。方法选取2019年6月~2022年6月在聊城市第二人民医院接受剖宫产分娩的sPE患者,根据发病孕龄的不同,进一步将其分为早发型sPE组(孕龄≤34周,n=45)和晚发型sPE组(孕龄>34周,n=55)。选取同期产检正常者100例为对照组。采用荧光定量PCR和免疫组织化学检测sPE患者胎盘中CD44和CD24表达,Pearson法分析其表达水平差异以及与sPE疾病临床特征的相关性,多因素logistic回归分析发生sPE的影响因素。结果相较于对照组,sPE胎盘组织中CD44 mRNA(0.55±0.12 vs 1.02±0.33),CD24 mRNA的表达水平(0.68±0.19vs 1.05±0.11)均降低,差异具有统计学意义(t=13.385,16.853,PsPE组胎盘组织中多呈阴性表达或弱阳性表达,而在对照组中多呈阳性表达,且sPE胎盘组织中CD44,CD24阳性率低于对照组,差异具有统计学意义(χ^(2)=9.696,14.346,PsPE组,晚发型sPE胎盘组织中CD44(0.65±0.17 vs 0.42±0.11),CD24(0.77±0.23 vs 0.58±0.13)mRNA的表达水平均较高,差异具有统计学意义(t=7.830,4.932,PsPE组BMI,收缩压、舒张压、尿蛋白、Cr,lDH和BUN均显著升高,差异有统计学意义(t=5.360~30.241,均PsPE组分娩孕周较早、MPV,AlB较低、新生儿出生身长较短和体质量较轻均低于对照组,差异具有统计学意义(t=3.232~11.109,均PsPE胎盘组织中CD44与CD24表达呈正相关(r=0.698,PsPE胎盘组织中CD44的表达分别与CD24,分娩孕周、MPV和新生儿出生身长呈正相关(r=0.611,0.639,0.612,0.465,均PlDH呈负相关(r=-0.604,-0.569,-0.593,均PlDH呈负相关(r=-0.637,-0.593,-0.561,均Plogistic回归分析结果显示,MPV(95%CI:1.429~4.350),尿蛋白(95%CI:1.529~2.709),lDH(95%CI:1.425~3.932)均是发生sPE的独立危险因素(均PsPE的独立保护因素(均PsPE患者胎盘中CD44,CD24表达水平较低,高水平CD44,CD24均是sPE发生的独立保护因素,可为后续sPE的治疗提供方向。

关键词：重度子痫前期细胞表面跨膜糖蛋白分子44 细胞表面跨膜糖蛋白分子24

Variation of Potential Nitrification and Ammonia-Oxidizing Bacterial Community with Plant-Growing Period in Apple Orchard soil

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2014年第2期13卷 415-425页

作者： lIU ling-zhi QIN si-jun lü De-guo WANG Bing-ying YANG Ze-yuan Key laboratory for Northern Fruit Cultivation and Physio-Ecology of shenyang City/College of Horticulture Shenyang Agricultural University College of land and Environment Shenyang Agricultural University Foreign language Department Shenyang Agricultural University

In this study, we investigated the potential nitrification and community structure of soil-based ammonia-oxidizing bacteria （AOB） in apple orchard soil during different growth periods and explored the effects of environmental factors on nitrification activity and AOB community composition in the soil of a Hanfu apple orchard, using a culture-dependent technique and denaturing gradient gel electrophoresis （DGGE）. We observed that nitrification activity and AOB abundance were the highest in November, lower in May, and the lowest in July. The results of statistical analysis indicated that total nitrogen （N） content, NH4＋-N content, NO3-N content, and pH showed significant correlations with AOB abundance and nitrification activity in soil. The shannon-Winner diversity, as well as species richness and evenness indices （determined by PCR-DGGE banding patterns） in soil samples were the highest in september, but the lowest in July, when compared to additional sampled dates. The DGGE fingerprints of soil-based 16s rRNA genes in November were apparently distinct from those observed in May, July, and september, possessing the lowest species richness indices and the highest dominance indices among all four growth periods. Fourteen DGGE bands were excised for sequencing. The resulting analysis indicated that all AOB communities belonged to the 13-Proteobacteria phylum, with the dominant AOB showing high similarity to the Nitrosospira genus. Therefore, soil-based environmental factors, such as pH variation and content of NHa＋-N and NO3--N, can substantially influence the abundance of AOB communities in soil, and play a critical role in soil-based nitrification kinetics.

关键词： apple orchard soil ammonia-oxidizing bacteria potential nitrification community structure PCR-dena~'ing gradientgel electrophoresis

Discovering the building blocks of atomic systems using machine learning:application to grain boundaries

在线全文

学校读者我要写书评

暂无评论

npj Computational Materials 2017年第1期3卷 212-218页

作者： Conrad W.Rosenbrock Eric R.Homer Gabor Csanyi Gus l.W.Hart Department of Physics and Astronomy Brigham Young UniversityProvoUT 84602USA Department of Mechanical Engineering Brigham Young UniversityProvoUT 84602USA Engineering laboratory University of CambridgeTrumpington StreetCambridge CB21PZUK

Machine learning has proven to be a valuable tool to approximate functions in high-dimensional ***,analysis of these models to extract the relevant physics is never as easy as applying machine learning to a large data set in the first *** we present a description of atomic systems that generates machine learning representations with a direct path to physical *** an example,we demonstrate its usefulness as a universal descriptor of grain boundary *** boundaries in crystalline materials are a quintessential example of a complex,high-dimensional system with broad impact on many physical properties including strength,ductility,corrosion resistance,crack resistance,and *** addition to modeling such properties,the method also provides insight into the physical“building blocks”that influence *** opens the way to discover the underlying physics behind behaviors by understanding which building blocks map to particular *** the structures are understood,they can then be optimized for desirable behaviors.

关键词： grain resistance corrosion

Morphometric and Biochemical Changes in Agave americana *** Induced By Ethyl Methanesulfonate

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Phyton-International Journal of Experimental Botany 2019年第3期88卷 277-284页

作者： s.J.Reyes-Zambrano M.l.Ramírez-Merchant C.Arias-Castro M.A.Rodríguez-Mendiola C.A.lecona-Guzmán V.M.Ruíz-Valdiviezo D.González-Mendoza F.A.Gutiérrez-Miceli laboratorio de Biotecnología Vegetal Instituto Tecnológico de Tuxtla GutiérrezTecnológico Nacional de México.Carretera Panamericana Km.1080TeránTuxtla GutiérrezChiapasC.P.29050México laboratorios de Análisis Instrumental Bioquímico DEPI del Instituto Tecnológico de TlajomulcoTecnológico Nacional de México.Tlajomulco de ZuñigaC.P.45640México Instituto de Ciencias Agrícolas Universidad Autónoma de Baja California(ICA-UABC)Carretera a Delta s/n Ejido Nuevo LeónCP.21705Baja CaliforniaMéxico

*** *** a crop with very little genetic *** order to evaluate the effect of ethyl methanesulfonate(EMs)to induce variability in in vitro plantlets of ***,different explants(meristems,leaves and roots)were evaluated for the production of *** medium supplemented with ANA(2.68μM)and BAP(2.68μM)was *** obtained from apical meristem were treated with 15 mM EMs for two hours after which shoot formation was induced using 2,4-D(0.11μM)and BAP(44μM).The EMs induced variations in the morphometric and morphological parameters of the plantlets obtained,with 60%of the plantlets presenting differences such as dwarfism and different leaf forms,without the presence of spines,as well as an increase in fructan content of 30%with respect to the control *** was increased and this activity is related with higher anthocyanins concentration in *** ***.

关键词： Fructans callus mutagenesis flavonoids anthocyanins phenylalanine ammonia lyase activity

Measurement of the integrated luminosities of cross-section scan data samples around theψ(3770)mass region

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 C 2018年第6期42卷 1-8页

作者： M. Ablikim M. N. Achasov s. Ahmed M. Albrecht M. Alekseev A. Amoroso F. F. An Q. An Y. Bai O. Bakina R. Baldini Ferroli Y. Ban K. Begzsuren D. W. Bennett J. V. Bennett N. Berger M. Bertani D. Bettoni F. Bianchi E. Boger I. Boyko R. A. Briere H. Cai X. Cai O. Cakir A. Calcaterra G. F. Cao s. A. Cetin J. Chai J. F. Chang W. l. Chang G. Chelkov G. Chen H. s. Chen J. C. Chen M. l. Chen P. l. Chen s. J. Chen X. R. Chen Y. B. Chen X. K. Chu G. Cibinetto F. Cossio H. a. Dai, J. F. Dai A. Dbeyssi D. Dedovich Z. Y. Deng A. Denig I. Denysenko M. Destefanis F. De Mori Y. Ding C. Dong J. Dong l. Y. Dong M. Y. Dong Z. l. Dou s. X. Du P. F. nuan J. Fang s. s. Fang Y. Fang R. Farinelli l. Fava s. Fegan F. Feldbauer G. Felici C. Q. Feng E. Fioravanti M. Fritsch C. D. Fu Q. Gao X. l. Gao Y. Gao, Y. G. Gao Z. Gao B. Garillon I. Garzia A. Gilman K. Goetzen l. Gong W. X. Gong W. Gradl M. Greco l. M. Gu M. H. Gu Y. T. Gu A. q. Guo l. B. Guo R. P. Guo Y. F. Guo A. Guskov Z. Haddadi s. Han X. Q. Hao F. A. Harris Z. l. He X. O. He F. H. Heinsius T. Held Y. K. Heng T. Holtmann Z. l. Hou H. M. Hu J. F. gu T. Hu Y. Hu G. s. Huang J. s. Huang X. T. Huang X. Z. Huang Z. l. guang T. Hussain W. Ikegami Andersson M Irshad Q. Ji Q. P. Ji X. B. Ji X. l. Ji X. s. Jiang X. Y. Jiang J. B. Jiao Z. Jiao D. P. Jin s. Jin Y. Jin T. Johansson A. Julin N. Kalantar-Nayestanaki X. s. Kang M. Kavatsyuk B. C. Ke T. Khan A. Khoukaz P. Kiese R. Kliemt l. Koch O. B. Kolcu B. Kopf M. Kornicer M. Kuemmel M. Kuessner A. Kupsc M. Kurth W. Kiihn J. s. lange M. lara P. larin l. lavezzi s. leiber H. leithofi C. li Cheng li D. M. li F. li F. Y. li G. li H. B. li H. J. li J. C. li J. W. li K. J. li Kang li Ke li lei li P. l. li P. R. li Q. Y. li T. li W. D. li W. G. li X. l. li X. N. li X. Q. li Z. B. li H. liang Y. F. liang Y. T. liang G. R. liao l. Z. liao J. libby C. X. lin D. X. lin s. liu B. J. liu C. X. liu D. liu D. Y. liu F. H. liu Fang liu Feng liu H. B. liu H. l liu H. M. liu Huanhuan liu Huihui liu J. B. liu J. Y. liu K. liu K. Y. liu Ke liu l. D. liu Q. liu s B. Y. Zhang144 C. C. Zhang1D. H. Zhang1 H. H. Zhang45H. Y. Zhang144 J. Zhang151 J. L. Zhang65 J. Q. Zhang4 J. W. Zhang1 J. Y. Zhang1 J. Z. Zhang151 K. Zhang151 L. Zhang46 S. F. Zhang35 T. J. Zhang3975 X. Y. Zhang38 Y. Zhang4457 Y. H. Zhang144 Y. T. Zhang4557 Yang Zhang1 Yao Zhang1 Yu Zhang51 Z. H. Zhang6 Z. P. Zhan57Z. Y. Zhang64 G. Zhao1J. W. Zhao144 J. Y. Zhao151 J. Z. Zhao144 Lei Zhao4457 Ling Zhao1 M. G. Zhao35 Q. Zhao1 S. J. Zhao67 T. C. Zhao1 Y. B. Zhao144 Z. G. Zhao4457 A. Zhemehugov2869 B. Zheng58J. P. Zheng144 W. J. Zheng38 Y. H. Zheng51B. Zhong33 L. Zhou144 Q. Zhou151 X. Zhou64 X. K. Zhou4457 X. R. Zhou4457 X. Y. Zhou1 A. N. Zhu151 J. Zhu35 J. Zhu45 K. Zhu1 K. J. Zhu1 S. Zhu1 S. H. Zhu56 X. L. Zhu46 Y. C. Zhu4457 Y. S. Zhu151 Z. A. Zhu151 J. Zhuang144B. S. Zou1 J. H. Zou1 （ 1 Institute of High Energy Physics Beijing 100049 China Beihang University Beijing 100191 China Beijing Institute of Petrochemical Technology Beijing 102617 China Bochum Ruhr-University D-44780 Bochum Germany Carnegie Mellon University Pittsburgh Pennsylvania 15213 USA Central China Normal University Wuhan 430079 China China Center of Advanced science and Technology Beijing 100190 China COMsATs Institute of Information Technology Lahore Defence Road Off Raiwind Road 54000 Lahore Pakistan G.I. Budker Institute of Nuclear Physics sB RAs （BINP） Novosibirsk 630090 Russia GsI Helmholtzcentre for Heavy Ion Research GmbH D-64291 Darmstadt Germany Guangxi Normal University Guilin 541004 China Guangxi University Nanning 530004 China Hangzhou Normal University Hangzhou 310036 China Helmholtz Institute Mainz JohannwJoachim-Becher-Weg 45 D-55099 Mainz Germany Henan Normal University Xinxiang 453007 China Henan University of science and Technology Luoyang 471003 China Huangshan College Huangshan 245000 China Hunan Normal University Changsha 410081 China Hunan University Changsha 410082 China Indian Institute of Tec

To investigate the nature of the Ψ（3770） resonance and to measure the cross section for e^＋e^-→DD, a cross-section scan data sample, distributed among 41 center-of-mass energy points from 3.73 to 3.89 GeV, was taken with the BEsIII detector operated at the BEPCII collider in the year 2010. By analyzing the large angle Bhabha scattering events, we measure the integrated luminosity of the data sample at each center-of-mass energy point. The total integrated luminosity of the data sample is 76.16±0.04±0.61 pb^-1, where the first uncertainty is statistical and the second systematic.

关键词： Bhabha scattering events integrated luminosity BEsⅢ

No benefit of flat head positioning in early moderate-severe acute ischaemic stroke: a HeadPosT study subgroup analysis

在线全文

学校读者我要写书评

暂无评论

stroke & Vascular Neurology 2020年第4期5卷 406-409页

作者： Alejandro M Brunser Menglu Ouyang Hisatomi Arima Pablo M lavados Thompson Robinson Paula Munoz-Venturelli Veronica V Olavarria laurent Billot Marre l Hackett lili song sandy Middleton Octavio Pontes-Neto Tsong-Hai lee Caroline Watkins Craig s Anderson Department of General Emergency Clinica Alemana de SantiagoClinica Alemana Universidad del DesarrolloSantiagoChile Department of Neurology and Psychiatry Clinica Alemana de SantiagoFaculty of MedicineClinica Alemana Universidad del DesarrolloSantiagoChile The George Institute for Global Health University of New South WalesSidneyNew South WalesAustralia The George Institute in China Peking University Health Science CenterBeijingChina Department of Preventive Medicine and Public Health Fukuoka UniversityFukuokaJapan Department of Cardiovascular sciences and NIHR leicester Biomedical Research Centre University of LeicesterLeicesterUnited Kingdom Faculty of Health and Wellbeing University of Central LancashirePrestonLancashireUnited Kingdom Nursing Research Institute St Vincent's Health Network Sydney AustraliaAustralian Catholic UniversitySydneyNew South WalesAustralia stroke service-Neurology Division Department of Neuroscience and Behavioral SciencesRibeirao Preto Medical SchoolUniversity of Sao PauloSao PauloBrazil stroke Center and Department of Neurology Linkou Chang Gung Memorial Hospital and College of MedicineChang Gung UniversityTaoyuanTaiwan

background Although the Head Positioning in acute stroke Trial(HeadPosT)showed no effect of the flat head position(FP;vs sitting up head position(sUP))on functional outcome,we hypothesised that it could still offer benefits if commenced early in those with acute ischaemic stroke(AIs)of at least moderate *** subgroup analysis of HeadPosT in participants with National Institutes of Health stroke scale(NIHss)scores≥7,≥10 and≥14,randomised to FP or sUPs of AIs onset on functional outcomes defined by a shift in scores on the modified Rankin scale(mRs)and death/disability(mRs scores 3-6),and any cardiovascular serious adverse *** regression analyses were undertaken adjusted for study design and baseline risk *** There was no significant differential treatment effect in patient subgroups defined by increasing baseline NIHss scores:adjusted OR and 95%CI for ordinal shift and binary(3-6)mRs scores:for NIHss≥7(n=867)0.92(0.67 to 1.25)and 0.74(0.52 to 1.04);NIHss≥10(n=606)0.80(0.58 to 1.10)and 0.77(0.49 to 1.19);NIHss≥14(n=378)0.82(0.54 to 1.24)and 1.22(0.69 to 2.14).Conclusions Early FP had no significant effect in patients with moderate-severe AIs.

关键词： acute analysis effect