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Q-Switched Raman Fiber Laser with Molybdenum Disulfide-Based Passive sa.urable Absorber

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Chinese Physics Letters 2016年第7期33卷 98-101页

作者： N.Hisa.uddin u.N.Zakaria M.Z.Zulkifli A.A.Latiff H.Ahmad S.W.Harun Photonics Research Center University of Malaya Department of Electrical Engineering Faculty of EngineeringUniversity of Malaya Aston Institute of Photonics Technologies Aston University

We demonstrate a Q-switched Raman fiber laser using molybdenum disulfide （MoS2） as a sa.urable absorber （sa）. The sa is assembled by depositing a mechanically exfoliated MoS2 onto a fiber ferrule facet before it is matched with another clean ferrule via a connector. It is inserted in a Raman fiber laser cavity with a total cavity length of about 8kin to generate a Q-switching pulse train operating at 1560.2nm. A 7.7-kin-long dispersion compensating fiber with 584 ***-i km-1 of dispersion is used as a nonlinear gain medium. As the pump power is increased from 395 m W to 422 m W, the repetition rate of the Q-switching pulses can be increased from 132.7 to 137.4 kHz while the pulse width is concurrently decreased from 3.35μs to 3.03μs. The maximum pulse energy of 54.3 nJ is obtained at the maximum pump power of 422 roW. These results show that the mechanically exfoliated MoS2 sa has a great potential to be used for pulse generation in Raman fiber laser systems.

关键词： of with sa Q-Switched Raman Fiber Laser with Molybdenum Disulfide-Based Passive sa.urable Absorber is in for been that

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HCG酶免疫电极的电化学特性

分析科学学报 2000年第3期16卷 234-237页

作者：董飒英吕鸣祥罗国安 725研究所青岛分部青岛266071 天津大学化工学院清华大学化学系

本文在研究 HCG(人绒毛膜促性腺激素 )酶免疫电极响应特性的基础上 ,详细讨论了电解质溶液的 p H值对生物电极的响应的影响。并利用尿素对抗原抗体进行解离。

关键词：人绒毛膜促性腺激素酶免疫电极电化学特性

Malignancy and mortality in a population-based cohort of patients with coeliac disease or ‘gluten sensitivity’

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World Journal of Gastroenterology 2007年第1期13卷 146-151页

作者： LA Anderson sa McMillan RGP Watson P Monaghan AT Gavin C Fox LJ Murray Queen's university Belfast Centre for Clinical and Population Sciences Belfast United Kingdom Royal Group of Hospitals Regional Immunology Service Belfast United Kingdom Royal Group of Hospitals Institute of Clinical Science Belfast United Kingdom. Queen's university Belfast Northern Ireland Cancer Registry Belfast United Kingdom

AIM: To determine the risk of malignancy and mortality in patients with a positive endomysial or anti-gliadin an- tibody test in Northern Ireland. METHODS: A population-based retrospective cohort study design was used. Laboratory test results used in the diagnosis of coeliac disease were obtained from the Regional Immunology Laboratory, cancer statistics from the Northern Ireland Cancer Registry and mortal- ity statistics from the General Registrar Office, Northern Ireland. Age standardized incidence ratios of malignant neoplasms and standardized mortality ratios of all-cause and cause-specific mortality were calculated. RESuLTS: A total of 13 338 people had an endomysial antibody and/or an anti-gliadin antibody test in Northern Ireland between 1993 and 1996. There were 490 pa- tients who tested positive for endomysial antibodies and they were assumed to have coeliac disease. There were 1133 patients who tested positive for anti-gliadin anti- bodies and they were defined as gluten sensitive. Ma- lignant neoplasms were not significantly associated with coeliac disease; however, all-cause mortality was signifi- cantly increased following diagnosis. The standardized incidence and mortality ratios for non-Hodgkin’s lym- phoma were increased in coeliac disease patients but did not reach statistical significance. Lung and breast cancer incidence were significantly lower and all-cause mortal-ity, mortality from malignant neoplasms, non-Hodgkin’s lymphoma and digestive system disorders were signifi- cantly higher in gluten sensitive patients compared to the Northern Ireland population. CONCLuSION: Patients with coeliac disease or gluten sensitivity had higher mortality rates than the Northern Ireland population. This association persists more than one year after diagnosis in patients testing positive for anti-gliadin antibodies. Breast cancer is significantly re- duced in the cohort of patients with gluten sensitivity.

关键词： Coeliac disease Cancer Mortality Gluten sensitivity

技术进步对污染物排放会存在选择性偏向吗?——来自环境信息视角的城市层面经验证据

维普期刊数据库评论

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维普期刊数据库

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苏州大学学报（哲学社会科学版） 2020年第2期41卷 114-122页

作者：王辉董直庆杨洒洒华东师范大学经济与管理学部上海200241

既有文献关注技术进步的污染减排效应,却普遍忽视技术进步是否对不同类型污染物排放存在选择性偏向。基于中国2003—2013年276个地级城市面板数据,采用随机前沿方法和工具变量法,检验环境信息披露约束条件下,技术进步是否对污染物排放... 详细信息

既有文献关注技术进步的污染减排效应,却普遍忽视技术进步是否对不同类型污染物排放存在选择性偏向。基于中国2003—2013年276个地级城市面板数据,采用随机前沿方法和工具变量法,检验环境信息披露约束条件下,技术进步是否对污染物排放存在选择性偏向问题。结果发现:技术进步对污染物排放存在选择性偏向。其中,技术进步显著抑制二氧化硫排放,但其与PM2.5呈倒u型关系且二者处于倒u型左侧,短期无法实现PM2.5的减排目标。环境信息披露政策将强化技术进步污染物减排的选择性偏向,且城市环境信息披露程度越强其技术进步的减排效果越明显,但较低程度的环境信息披露作用有限。

关键词：技术进步污染物排放环境信息披露

Forward pion-nucleon charge exchange reaction and Regge constraints

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Chinese Physics C 2009年第12期33卷 1318-1322页

作者：黄飞 A. Sibirtsev S. Krewald C. Hanhart J. Haidenbauer u.-G. Meiβner Department of Physics and Astronomy University of Georgia Athens Georgia 30602 USA Helmholtz-Institut fr Strahlen-und Kernphysik und Bethe Center for Theoretical Physics Universitt Bonn D-53115 Bonn Germany Excited Baryon Analysis Center Thomas Jefferson National Accelerator Facility Newport News Virginia 23606 USA Institut fr Kernphysik and Jlich Center for Hadron Physics Forschungszentrum Jlich D-52425 Jlich Germany Institute of Advanced Simulation Forschungszentrum Jlich D-52425 Jlich Germany

We present our recent study of pion-nucleon charge exchange amplitudes above 2 GeV. We analyze the forward pion-nucleon charge exchange reaction data in a Regge model and compare the resulting amplitudes with those from the Karlsruhe-Helsinki and George-Washington-university partial-wave analyses. We explore possible high-energy constraints for theoretical baryon resonance analyses in the energy region above 2 GeV. Our results show that for the pion-nucleon charge exchange reaction, the appropriate energy region for matching meson-nucleon dynamics to diffractive scattering should be around 3 GeV for the helicity flip amplitude.

关键词： pion-nucleon interaction Regge model

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龙门导轨磨床立柱动静态特性分析及优化设计

科学技术与工程 2014年第28期22卷 191-194,225页

作者：母德强范以撒杨君吕恕卫长春工业大学机电工程学院长春130012

以MM52160导轨磨床立柱为研究对象,首先采用Spaceclaim软件建立龙门导轨磨床立柱的三维实体模型,并利用Hypermesh有限元软件对该模型进行前处理,建立立柱的有限元模型。对该有限元模型进行动静态特性分析,然后以立柱的质量作为目标函数... 详细信息

以MM52160导轨磨床立柱为研究对象,首先采用Spaceclaim软件建立龙门导轨磨床立柱的三维实体模型,并利用Hypermesh有限元软件对该模型进行前处理,建立立柱的有限元模型。对该有限元模型进行动静态特性分析,然后以立柱的质量作为目标函数,最大变形量作为约束函数,选择对立柱性能影响较大的灵敏度尺寸作为优化设计变量,进行多目标尺寸优化。优化后立柱的整体质量减少了113.2 kg,减少量约为总质量的7.3%;最大变形量减小了2.833μm,减小量约为总变形量的10.7%。实现了在保证立柱刚度的前提下,立柱的质量和最大变形量降低的目的。

关键词：磨床立柱静力分析有限元分析动力学分析

Improving the Control System for Pumped Storage Hydro Plant

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Improving the Control System for Pumped Storage Hydro Plant

An exotic Cretaceous kimberlite linked to metasomatized lithospheric mantle beneath the southwestern margin of the S?o Francisco Craton,Brazil

International Conference on Computer Communication and Management（ICCCM 2011）

作者： sa’ad. P. Mansoor university of Wales Bangor Gwynedd LL57 1UT U.K.

The operational flexibility of pump storage hydro-stations means that they are often used on a power system （grid） as a means of controlling system frequency and for load management. When used in this role, the response of the generator is determined by the behaviour of its control system （governor）. The basic function of a governor is to control frequency variation of the grid where its droop characteristics ensure equitable load sharing between generating units in order to ensure satisfactory and stable operation. The governor setting and in particular the loop gains, are therefore critical to achieving optimum levels of performance. In this paper, a step-by-step procedure taken to construct the new governor is presented. The most relevant results on the evaluation of the governor are shown and its performance advantages compared to the current governor are highlighted.

关键词： governor pump storage control

来源： cnki会议评论

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Geoscience Frontiers 2022年第1期13卷 182-203页

作者： Luísa D.V.Carvalho Tiago Jalowitzki Ricardo Scholz Guilherme O.Gonçalves Marcelo Peres Rocha Rogério Silvestre Pereira Cristiano Lana Marco Paulo de Castro Gláucia Queiroga Reinhardt A.Fuck universidade Federal de Ouro Preto(uFOP) Escola de MinasDepartamento de GeologiaCampus Morro do Cruzeiro35400-000 Ouro PretoMGBrazil universidade de Brasília(unB) Instituto de GeociênciasCampus Universitário Darcy Ribeiro70910-900 BrasíliaDFBrazil Independent Geologist Consultant

We present major and trace element compositions of mineral concentrates comprising garnet xenocrysts,ilmenite,phlogopite,spinel,zircon,and uncommon minerals(titanite,calzirtite,anatase,baddeleyite and pyrochlore)of a newly discovered Late Cretaceous kimberlite(u-Pb zircon age 90.0±1.3 Ma;2σ)named Osvaldo Franca 1,located in the Alto Paranaíba Igneous Province(APIP),southeastern *** grains are lherzolitic(Lherz-1,Lherz-2 and Lherz-3),harzburgitic(Harz-3)and wehrlitic(Wehr-2).The pyrope xenocrysts cover a wide mantle column in the subcratonic lithosphere(66–143 km;20–43 kbar)at relatively low temperatures(811–875°C).The shallowest part of this mantle is represented by Lherz-1 pyropes(20–32 kbar),which have low-Cr(Cr_(2)O_(3)=1.74–6.89 wt.%)and fractionated middle to heavy rare earth elements(MREE-HREE)*** deepest samples are represented by Lherz-2,Lherz-3,Harz-3,and Wehr-2 pyropes(36–43 kbar).They contain high-Cr contents(Cr_(2)O_(3)=7.36–11.19 wt.%)and are characterized by sinusoidal(Lherz-2 and Wehr-2)and spoon-like(Lherz-3 and Harz-3)REE *** to their REE and trace elements,pyrope xenocrysts have enriched nature(e.g.,Ce and Yb ***_(2)O_(3)),indicating that the cratonic lithosphere has been affected by a silicate melt with subalkaline/tholeiite composition due to their low Zr,Ti and Y *** minerals with typical kimberlitic signatures,such as ilmenite and zircon,the exotic compositions of phlogopite and ulvöspinel suggest an enriched component in the magma *** formation of rare mineral phases with strong enrichment of light-REE(LREE)and high field strength elements(HFSE)is attributed to the late-stage kimberlitic *** propose a tectonic model where a thermal anomaly,represented by the low-velocity seismic anomaly observed in P-wave seismic tomography images,supplied heat to activate the alkaline magmatism from a metasomatized cratonic mantle source during the late-stages of Gondwana fragmentation and conse

关键词： Osvaldo França 1 kimberlite Alto Paranaíba Igneous Province Metasomatized cratonic lithosphere Zircon u-Pb geochronology

技术进步能源偏向性、能源消费结构与中国能源强度

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东北师大学报（哲学社会科学版） 2022年第1期 75-87页

作者：王林辉杨洒洒刘备华东师范大学经济与管理学部上海200241 厦门大学经济学院福建厦门361005 南京邮电大学管理学院江苏南京210003

选取中国30个省(市)2004—2015年的数据,通过构建双层嵌套CES生产函数,采用四方程标准化供给面系统方程和广义非线性最小二乘法估算分省能源偏向性程度,研究技术进步能源偏向性对能源强度的作用。结果发现:技术进步能源偏向性与能源强... 详细信息

选取中国30个省(市)2004—2015年的数据,通过构建双层嵌套CES生产函数,采用四方程标准化供给面系统方程和广义非线性最小二乘法估算分省能源偏向性程度,研究技术进步能源偏向性对能源强度的作用。结果发现:技术进步能源偏向性与能源强度呈现显著的倒u型关系,可由技术进步能源偏向性的生产率效应与要素偏向效应所解释,当生产率效应占优,技术进步能源偏向性降低能源强度,而要素偏向效应占优结果相反。技术进步能源偏向性对清洁与非清洁能源强度的作用呈现非一致性,技术进步能源偏向性可通过调整能源消费结构实现对能源强度的作用。市场型的碳排放权交易政策实施可有效实现有偏技术进步的节能作用,政府干预型环境规制政策强度不同,技术进步能源偏向性对能源强度的作用迥异,相对严格的环境规制能促进有偏技术进步节能效应的发挥。

关键词：技术进步能源偏向性能源强度能源消费结构环境规制