检索结果-南通市图书馆

A model of regional economic development with increasing returns

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University.Science A(Applied Phy.ics & Engineering) 2007年第1期8卷 164-170页

作者： qian edward y. y.O y.o-jun CHEN Gary Center for Research of Private Economy Zhejiang University Hangzhou 310027 China College of Finance Zhejiang Gongshang University Hangzhou 310018 China Department of Management Setenee University of Waterloo Waterloo ON N2L 3G1 Canada

This paper develops mathematically.and empirically.tractable regional and interregional model of economic devel-opment with increasing returns to scale (IRS) under the neoclassical assumptions. A one-sector, two-region model in which one region exhibits IRS is presented and the whole nation presents constant returns to scale. The development of the local IRS economy.is shown to be constrained to a “moving equilibrium” path. The preliminary.empirical results are sufficiently.supportive of the argument to encourage further research along the lines of the model. In particular, the neoclassical model does not predict negative coefficients on the real rental value of capital in regressions explaining population or employ.ent relative to that in the nation.

关键词：经济发展模型区域经济收益增长动平衡规模收益递增

Large optical nonlinearity.enabled by.coupled metallic quantum wells

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2019年第1期8卷 1069-1075页

作者： Haoliang qian Shilong Li Ching-Fu Chen Su-Wen Hsu Steven edward Bopp qian Ma Andrea R.Tao Zhaowei Liu Department of Electrical and Computer Engineering University of CaliforniaSan Diego9500 Gilman DriveLa JollaCA 92093USA Department of NanoEngineering University of CaliforniaSan Diego9500 Gilman DriveLa JollaCA 92093USA Materials Science and Engineering University of CaliforniaSan Diego9500 Gilman DriveLa JollaCA 92093USA Center for Memory.and Recording Research University of CaliforniaSan Diego9500 Gilman DriveLa JollaCA 92093USA

New materials that exhibit strong second-order optical nonlinearities at a desired operational frequency.are of paramount importance for nonlinear *** second-order susceptibility.χ^((2)) has been obtained in semiconductor quantum wells(QWs).Unfortunately.the limited confining potential in semiconductor QWs causes formidable challenges in scaling such a scheme to the visible/near-infrared(NIR)frequencies for more vital nonlinear-optic ***,we introduce a metal/dielectric heterostructured platform,i.e.,TiN/Al_(2)O_(3) epitaxial multilay.rs,to overcome that *** platform has an extremely.high χ^((2)) of approximately.1500 pm/V at NIR *** combining the aforementioned heterostructure with the large electric field enhancement afforded by.a nanostructured metasurface,the power efficiency.of second harmonic generation(SHG)achieved 10^(−4) at an incident pulse intensity.of 10 GW/cm^(2),which is an improvement of several orders of magnitude compared to that of previous demonstrations from nonlinear surfaces at similar *** proposed quantum-engineered heterostructures enable efficient wave mixing at visible/NIR frequencies into ultracompact nonlinear optical devices.

关键词： quantum nonlinear visible

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

Migraine and stroke

Stroke & Vascular Neurology 2017年第3期2卷 160-167页

作者： y.nghua Zhang Aasheeta Parikh Shuo qian edward Neurosciences Institute in affiliation with Northwestern Medicine NapervilleIllinoisUSA Department of Neurology.Rehabilitation University of IllinoisChicagoIllinoisUSA

Migraines are generally.considered a relatively.benign neurological ***,research has shown an association between migraines and stroke,and especially.between migraine with aura and ischaemic *** can also suffer from migrainous infarction,a subset of ischaemic stroke that often occurs in the posterior circulation of y.unger *** exact pathogenesis of migrainous infarct is not known,but it is theorised that the duration and local neuronal energy.level from cortical spreading depression may.be a key.*** factors contributing to migrainous infarct may.include vascular,inflammatory.endothelial structure,patent foramen ovale,gender,oral contraceptive pill use and *** such as the triptan and ergot class are commonly.used to treat migraines and may.also play.a *** is also shown to be correlated to haemorrhagic stroke,although studies do not demonstrate causation versus association,and further studies are *** are also some rare genetic diseases such as cerebral autosomal-dominant arteriopathy.with subcortical infarcts and leukoencephalopathy.retinal vasculopathy.with cerebral leukody.trophy.and others,which can cause both migraines and *** imaging,many.migraineurs are found to have white matter changes similar to those seen in patients with *** may.be caused in part by.alterations in resting cerebral blood flow and vasoconstrictor *** treating patients with migraines,it is important to identify.and modify.any.vascular risk factors such as hy.ertension,smoking,oral contraceptive pill use and lifesty.e *** studies will determine if more aggressive treatment of migraines can ultimately.lead to fewer strokes in this population.

关键词： Migraine alterations y.unger

Modeling study.of solid-particle erosion with consideration of particle velocity.dependent model parameters

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

International Journal of Modeling, Simulation, and Scientific Computing 2016年第3期7卷 243-262页

作者： Shijie qian Kuiy.ng Chen Rong Liu Ming Liang Department of Mechanical Engineering University.of Ottawa 770 King edward Avenue OttawaONK1N 6N5Canada Institute for Aerospace Research National Research Council Canada 1200 Montreal Road OttawaONK1A 0R6Canada Department of Mechanical and Aerospace Engineering Carleton University.1125 Colonel By.Drive OttawaONK1S 5B6Canada

An advanced erosion model that correlates two model parameters—the energies required to remove unit mass of target material during cutting wear and deformation wear,respectively.with particle velocity.particle size and density.as well as target material properties,is *** model is capable of predicting the erosion rates for a material under solid-particle impact over a specific range of particle velocity.at the impingement angle between 0◦and 90◦,provided that the experimental data of erosion rate for the material at a particle velocity.within this range and at impingement angles between 0◦and 90◦are *** proposed model is applied on three distinct ty.es of materials:aluminum,perspex and graphite,to investigate the dependence behavior of the model parameters on particle velocity.for ductile and brittle *** predicted model parameters obtained from the model are validated by.the experimental data of aluminum plate under Al2O3 particle *** significance and limitation of the model are discussed;possible improvements on the model are suggested.

关键词： Solid-particle erosion particle impact velocity particle impingement angle cutting wear deformation wear erosion rate

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

扩展青霉侵染对苹果果实膜磷脂代谢的影响

食品科学 2021年第3期42卷 211-218页

作者：彭慧龚迪魏亚楠杨乾宗元元 Dov PRUSKy.edward SIONOV 毕阳甘肃农业大学食品科学与工程学院甘肃兰州730070 以色列农业研究组织农产品采后科学部以色列里雄莱锡安7505101

目的:研究扩展青霉侵染对苹果果实膜透性及膜磷脂代谢的影响。方法:以‘元帅’苹果为试材,测定扩展青霉损伤接种果实病健交界处组织的细胞膜透率、膜磷脂代谢关键酶活力以及相关底物和产物含量的变化。结果:扩展青霉侵染早期(2 d前)果... 详细信息

目的:研究扩展青霉侵染对苹果果实膜透性及膜磷脂代谢的影响。方法:以‘元帅’苹果为试材,测定扩展青霉损伤接种果实病健交界处组织的细胞膜透率、膜磷脂代谢关键酶活力以及相关底物和产物含量的变化。结果:扩展青霉侵染早期(2 d前)果实病斑直径无明显变化,侵染后期(2 d后)果实病斑直径和细胞膜透率明显增大。侵染期间,果实的磷脂酶A2、磷脂酶C和磷脂酶D活力,以及磷脂酸含量持续升高,磷脂酰胆碱和磷脂酰肌醇含量逐渐降低;磷脂酰胆碱、磷脂酰肌醇和磷脂酸与对照组的显著差异出现在侵染后期。此外,侵染早期果实的不饱和脂肪酸含量迅速升高,第2天时油酸、亚油酸和亚麻酸含量分别高出对照组31.58%、55.57%和43.67%;侵染后期果实的饱和脂肪酸含量快速升高,第6天时的棕榈酸和硬脂酸含量分别高出对照组49.46%和43.39%。侵染果实的脂肪酸不饱和度早期高于对照组,后期低于对照组。相关性分析表明,侵染果实细胞膜透率与磷脂酶A2、磷脂酶C和磷脂酶D活力,以及磷脂酸、棕榈酸和硬脂酸含量呈极显著正相关,但与磷脂酰胆碱和磷脂酰肌醇含量呈极显著负相关。结论:扩展青霉侵染激活了果实的磷脂酶,促进了膜磷脂的降解和脂肪酸的释放,破坏了细胞膜的完整性。侵染早期不饱和脂肪酸的迅速释放可能与果实抗性相关。

关键词：苹果扩展青霉细胞膜完整性磷脂代谢

Blood lead level in Chinese adults with and without coronary.artery.disease

在线全文

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2021年第11期18卷 857-866页

作者： Shi-Hong LI Hong-Ju ZHANG Xiao-Dong LI Jian CUI y.-Tong CHENG qian WANG Su WANG Chay.krit Krittanawong edward A El-Am Rody.G.Bou Chaay. Xiang-y. WU Wei GU Hong-Hong LIU Xian-Liang y.N Zhi-Zhong LI Shi-Wei y.NG Tao SUN Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijingChina Department of Echocardiography Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina Department of Cardiology Shougang Changzhi Steel HospitalChangzhiChina Department of Cardiology Baylor College of MedicineHoustonUSA Department of Medicine Indiana University School of MedicineIndianapolisUSA

BACKGROUND The Trial to Assess Chelation Therapy.study.found that edetate disodium(disodium ethy.enediaminetet-raacetic acid)chelation therapy.significantly.reduced the incidence of cardiac events in stable post-my.cardial infarction patients,and a body.of epidemiological data has shown that accumulation of biologically.active metals,such as lead and cadmium,is an important risk factor for cardiovascular ***,limited studies have focused on the relationship between angiograph-ically.diagnosed coronary.artery.disease(CAD)and lead *** study.compared blood lead level(BLL)in Chinese pa-tients with and without *** In this prospective,observational study.450 consecutive patients admitted to Beijing Anzhen Hospital with sus-pected CAD from November 1,2018,to January.30,2019,were *** patients underwent coronary.angiography.and an experienced heart team calculated the Sy.TAX scores(SXscore)for all available coronary.*** were determined with atomic absorption spectrophotometry.and compared between patients with angiographically.diagnosed CAD and those without *** In total,343(76%)patients had CAD,of whom 42%had low(0−22),22%had intermediate(23−32),and 36%had high(≥33)*** were 36.8±16.95μg/L in patients with CAD and 31.2±15.75μg/L in those without CAD(P=0.003).When BLLs were categorized into three groups(low,middle,high),CAD prevalence increased with increasing BLLs(Py.associated with intermediate and high SXscore(adjusted OR:1.050,95%CI:1.036-1.066;Py.associated with angiographically.diagnosed ***,BLLs showed excel-lent predictive value for SXscore,especially.for complex coronary.artery.lesions.

关键词： coronary Blood admitted

在线全文

学校读者我要写书评

暂无评论

肖邦的叙事曲

音乐艺术（上海音乐学院学报） 2006年第1期 6-13页

作者：爱德华·巴克斯特·培理（edward Baxter Perry.[美] 钱仁康（译）不详上海音乐学院教授上海200031

本文译自美国钢琴家及音乐学家爱德华·巴克斯特·培理的《钢琴作品描绘性分析》一书,内容解释“叙事曲”一语的由来、肖邦的叙事曲和密茨凯维支的叙事诗的关系,并分析肖邦的第一、第二和第三首叙事曲。

关键词：叙事曲密茨凯维支《康拉德·华伦洛德》《希维德什湖》肖邦钢琴

Biodegradation Kinetics and Mechanism of a Ty.ical Coal Gasification Pollutant:Quinoline

在线全文

学校读者我要写书评

暂无评论

Journal of Harbin Institute of Technology.New Series) 2014年第6期21卷 121-128页

作者： Peng Xu Hong-Jun Han Sheng-y.ng Jia Bao-Lin Hou Hai-Feng Zhuang qian Zhao State Key.Laboratory.of Urban Water Resource and Environment Harbin Institute of Technology

A strain Pseudomonas ***1 was isolated from activated sludge and characterized by.morphological observation,biochemical and phy.iological identification as well as 16 S rRNA gene sequence *** was a gram-negative,non-motile,rod-shaped with colonies which were white,opaque,small and wrinkled on solid *** strain was negative for catalase,gelatin liquefaction,M.R and V.P tests and was unable to reduce / restore *** 1406 bp 16 S rRNA gene fragment of PP1 was more than 99% identical to the Pseudomonas *** of quinoline as single substrate was conducted in batch experiments at different temperatures( 15- 40 ℃) and p H values( 5- 10).The results indicate that the optimum conditions for the degradation of quinoline by.PP1 were 30 ℃ and p H *** ***1 was able to degrade 97.1%,95.4%,94.8%,63.6% and 40.4% quinoline when initial concentrations of quinoline were 50,100,200,300,and 400 mg / L,respectively.and lag phases were prolonged from 2 h to 10 *** maximum degradation rate( q) was obtained at an initial quinoline concentration( S0) of about 100 mg/L with q of *** experimentally.obtained q values at various initial S0 were fitted by.Haldane model,y.no model,Aiba model,edward model and Webb model,and the results demonstrated that Haldane model gives the best fit for strain PP1 with coefficient of determination,R2= 0.9124 and SDavg= *** metabolic intermediates were identified by.high performance liquid chromatograph( HPLC) and GC / ***,a possible pathway.containing 5,6-dihy.roxy.2-oxo-1,2-dihy.roquinoline as an intermediate was proposed for the first time.

关键词： pseudomonas sp. quinoline biodegradation kinetics pathway

Tubular apocrine adenoma of the upper ey.lid:a case report and literature review

在线全文

学校读者我要写书评

暂无评论

International Journal of Dermatology.and Venereology 2018年第2期1卷 117-119页

作者： Si-Qi Fu Hai-Jing Wu edward I.Herman Jing Zhang Gui-y.ng Zhang y.ng Zhou qian-Jin Lu y.n-Nan Wang Department of Dermatology the Second Xiangya Hospital Central South University Changsha Hunan 410011 China St.Vincent' s Medical Center Bridgeport CT 06606 USA Xiangy. School of Medicine Central South University Changsha Hunan 410013 China

Introduction Tubular Apocrine Adenoma (TAA) is a rare benign adnexal neoplasm with apocrine differentiation,which is now considered as a part of the spectrum of tubular *** with TAA usually.presents as a asy.ptomatic,solitary.slow-growing cutaneous nodule or a pedunculated *** has a predilection for the scalp,occasionally.on the face,axilla,and anogenital ***,we reported a case of TAA appearing on the left upper ey.lid of a 23-y.ar-old Chinese man,and further analy.ed retrospectively.the features of facial TAA cases proviously.reported in the world.

关键词：