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生物多样性 1995年第B6期3卷 30-35页

作者： SHIYOU LI KENt t. ADAIR the tucker Center. Stephen F. Austin State University. Nacogdoches. texas 75962. USA

towards critical and supercritical electromagnetic fields

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High Power Laser Science and Engineering 2023年第2期11卷 26-36页

作者： M.Marklund t.G.Blackburn A.Gonoskov J.Magnusson S.S.Bulanov A.Ilderton Department of Physics University of GothenburgGothenburgSweden Lawrence Berkeley National Laboratory BerkeleyCaliforniaUSA Higgs Centre School of Physics and AstronomyUniversity of EdinburghEdinburghUK

the availability of ever stronger,laser-generated electromagnetic fields underpins continuing progress in the study and application of nonlinear phenomena in basic physical systems,ranging from molecules and atoms to relativistic plasmas and quantum electrodynamics.this raises the question:how far will we be able to go with future lasers?One exciting prospect is the attainment of field strengths approaching the Schwinger critical field Ecr in the laboratory frame,such that the field invariant E^(2)−c^(2)B^(2)>E_(cr)^(2) is reached.the feasibility of doing so has been questioned,on the basis that cascade generation of dense electron–positron plasma would inevitably lead to absorption or screening of the incident light.Here we discuss the potential for future lasers to overcome such obstacles,by combining the concept of multiple colliding laser pulses with that of frequency upshifting via a tailored laser–plasma interaction.this compresses the electromagnetic field energy into a region of nanometre size and attosecond duration,which increases the field magnitude at fixed power but also suppresses pair cascades.Our results indicate that laser facilities with peak power of tens of PW could be capable of reaching Ecr.Such a scenario opens up prospects for the experimental investigation of phenomena previously considered to occur only in the most extreme environments in the universe.

关键词： Schwinger effect advanced focusing concepts attosecond pulses dipole wave surface high-order harmonic generation

Cardiorespiratory and muscular fitness associations with older adolescent cognitive control

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Journal of Sport and Health Science 2021年第1期10卷 82-90,I0001页

作者： tatsuya t.Shigeta Angus A.Leahy Jordan J.Smith Narelle Eather David R.Lubans Charles H.Hillman Department of Psychology Northeastern UniversityBostonMA 02115USA Priority Research Centre for Physical Activity and Nutrition School of EducationUniversity of NewcastleCallaghanNSW 2308Australia Department of Physical therapy Movement&Rehabilitation SciencesNortheastern UniversityBostonMA 02131USA

Background:Participation in physical activity supports greater cardiorespiratory fitness(CRF),a correlate of cognitive control.However,the relationship between muscular fitness(MF)and cognitive control is less clear.the present study investigated the differential relationship of CRF and MF with cognitive control in older adolescents.Methods:this cross-sectional study involved students(1517 years old,n=541,43%female)from 20 secondary schools who completed tests of inhibition(modified flanker task),working memory(n-back task),CRF(Progressive Aerobic Cardiovascular Endurance Run),and MF(standing long jump and push-up test).Multilevel analyses tested the association between CRF or MF and cognitive outcomes while accounting for the influence of the other fitness variable and relevant demographic factors.Results:CRF predicted response accuracy during incongruent flanker trials,the condition requiring greater inhibition.For the working memory task,CRF predicted greater target accuracy and greater d’scores on the 1-back task,requiring lesser amounts of working memory.In the 2-back task,which requires greater amounts of working memory,CRF also predicted greater target and non-target accuracy and d’scores.Comparatively,MF did not predict any cognitive outcomes after adjustment for CRF.Conclusion:CRF was selectively related to better performance during task conditions that require greater amounts of inhibition and working memory.this finding suggests that CRF,but not MF,may benefit cognitive control in older adolescents.this selective influence of CRF on older adolescents’cognition highlights the value of aerobic physical activity.

关键词： Adolescence Cognition Physical activity Physical fitness

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SiC/C薄膜的制备及其力学性能

复合材料学报 2005年第1期22卷 74-78页

作者：王新华 YOSHI DA t 浙江大学材料科学与工程系杭州310027 东京大学材料工程系

　以SiC超细粉为原料、采用热等离子体物理气相沉积(tPPVD)技术快速制备出了高质量SiC/C薄膜,最大沉积速度达到225nm/s,高于常规物理气相沉积(PVD)和化学气相沉积(CVD)法两个数量级。用扫描电子显微镜、高分辨透射电子显微镜和X射线光... 详细信息

　以SiC超细粉为原料、采用热等离子体物理气相沉积(tPPVD)技术快速制备出了高质量SiC/C薄膜,最大沉积速度达到225nm/s,高于常规物理气相沉积(PVD)和化学气相沉积(CVD)法两个数量级。用扫描电子显微镜、高分辨透射电子显微镜和X射线光电子谱对薄膜的形貌和微结构进行了观察和分析,并用纳牛力学探针测定了薄膜的力学性能。研究结果表明,向等离子体中导入CH4,SiC/C薄膜沉积速度增大,薄膜中C含量增加,薄膜断面呈现柱状结构。薄膜硬度和弹性模量随薄膜中C含量增加而降低,在接触深度为40nm时由纳牛力学探针测得沉积薄膜的最大硬度达到38GPa。

关键词：薄膜 SiC/C 硬度力学性能

the state of the art in scale inhibitor squeeze treatment

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Petroleum Science 2020年第6期17卷 1579-1601页

作者： Amy t.Kan Zhaoyi Dai Mason B.tomson Department of Civil and Environmental Engineering Rice University6100 Main StreetHoustonTX 77005USA

the mechanistic understanding of the reactions that govern the inhibitor retention and release,modeling,and the state-ofthe-art innovation in squeeze treatment are reviewed.the retention and release are governed by(1)the amount of calcite that can dissolve prior to inhibitor-induced surface poisoning;(2)calcite surface poisoning after^20 molecular layers of surface coverage by the adsorbed inhibitors to retard further calcite dissolution;(3)less base,CO3^2-,is released into the aqueous solution;(4)formation of the more acidic inhibitor precipitates;(5)phase transformation and maturation of the more acidic inhibitor precipitates;and(6)dissolution of the less soluble crystalline inhibitor precipitates.the trend to advance squeeze technologies is through(1)enhancing scale inhibitor retention,(2)optimizing the delivery of scale inhibitors to the target zone,and(3)improving monitoring methods.Lastly,a prototype yardstick for measuring the squeeze performance is used to compare the squeeze life of 17 actual squeeze treatments.Even though the various squeeze treatments appear to be different.all published squeeze durations can be rated based on the normalized squeeze life per unit mass of inhibitors.

关键词： Scale inhibitor squeeze Inhibitor retention Surface poisoning Adsorption Squeeze life

固体绝缘材料中气隙缺陷局部放电特性仿真的研究进展（英文）

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固体绝缘材料中气隙缺陷局部放电特性仿真的研究进展（英文）

Genotoxicity of Pesticide Waste Contaminated Soil and Its Leachate

第十八届全国等离子体科学技术会议

作者： Muhammad Farasat.abbas Anbang Sun Guanjun Zhang Mingxiao Zhu School of Electrical Engineering Xi’an Jiaotong University

Partial discharge(PD) is an important tool for condition assessment of dielectric insulation material of high voltage equipment.Partial discharge can occur in liquid,gas and solid material.Voids and cavities are commonly known defects present into solid dielectric insulation material due to manufacturing or during installation of power equipment.these micro-voids when go under high voltage stress exhibit PD phenomenon.the repetition of PD activity into small voids can lead to failure of insulation material.Measurement of PD is essential to assess the condition of insulation material but through modelling we can get deep sight into PD phenomenon and derive the relationship between different applied stresses(applied voltage,applied frequency,shape,size and location of cavity) and PD activity.So far,in previous researches different kinds of models are presented to explain partial discharge into voids or cavities.the three capacitance model(abc) model is the basic representation of PD.Induced charge concept model presented by Pedersen in counter of abc model.Finite element analysis(FEA) model is also presented to represent the PD phenomenon in small voids or cavities.this paper gives a precise review of partial discharge modelling into small voids or cavities ded into solid dielectric insulation material.the advantages and limitations of these models are presented and discussed in detail.the findings of these models are presented and discussed.In addition,some modifications are suggested to make the modelling of PD more rigorous.

关键词： partial discharge solid dielectric insulation material

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Biomedical and Environmental Sciences 2004年第3期17卷 257-265页

作者： S.D.SIVANESAN K.KRISHNAMURtHI S.D.WACHASUNDER t.CHAKRABARtI Environmental Biotechnology Division Environmental Biotechnology DivisionInstrumentation Division National Environmental Engineering Research Institute Nehru Marg Nagpur-440 020 IndiaEnvironmental Biotechnology Division

Objective Improper land disposal of hazardous waste can result in leaching of hazardous constituents which may contaminate ground and surface water leading to adverse impact on human health and environment consequences. the present study utilized mammalian cell culture for the genotoxicity assessment of waste and its leachate. Methods Genotoxic potential and chemical analysis of pesticide derived tarry waste contaminated soil extract and its leachate was assessed using in vitro human lymphocyte cultures and GC-MS. Results the investigation revealed that the soil extract could cause significant to highly significant genotoxicity in the form of DNA strand break at 25 mL (Ption at 25 mL (Pthe leachate could cause significant DNA strand break and chromosomal aberration only at 100 mL and 200 mL (Pthe genotoxicity observed is attributed to carbaril and tetra methyl naphthyl carbamate, the major ingredients of the extracts, as revealed by GC-MS.

关键词： Genotoxicity Soil extract Leachate DNA strand break Chromosomal aberration Gas chromatography mass spectrometery (GC-MS) Fluorimetric analysis of DNA unwinding assay (FADU)

the rigorous adjustment of the global mean sea level budget during 2005-2015

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Geodesy and Geodynamics 2021年第3期12卷 175-180页

作者： H.Bâki Iz t.Y.Yang C.K.Shum Division of Geodetic Science School of Earth SciencesThe Ohio State UniversityColumbusOHUSA

Global mean sea level budget is rigorously adjusted during the period 2005-2015.the emphasis is to provide the best estimates for the linear rates of changes(trends)of the global mean sea level budget components during this period subject to the constraint:Earth’s hydrosphere conserves water.the newly simultaneously adjusted trends of the budget components suggest a larger correction for the global mean sea level trend implicated by the other budget components’trends under the budget constraint.the simultaneous estimation of the linear trends of the budget components subject to the constraint for closure improves their uncertainties and enables a holistic assessment of the global mean sea budget,which has implications for future sea level science studies,including the future Intergovernmental Panel on Climate Change(IPCC)Assessment Reports,and the US Climate Assessment Reports.

关键词： Climate change Misclosure Global mean sea level Rigorous adjustment

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孔隙介质中的高速流

天然气勘探与开发 1998年第3期21卷 70-74页

作者： abbas Firoozabadi 李志周刘义成胡雪滨江汉石油管理局勘探开发研究院

高速气流所形成的压力降要大于由达西定律预测的压力降,这一观点已从理论和实践上得到了证实。本文的目的是总结以前的文献对这一现象的认识,并澄清目前已形成的错误概念。另外,还通过流动实验分析论证了这一结论。

关键词：孔隙介质高速气流达西定律

Does supplier concentration matter to investors during the COV1D-19 crisis:evidence from China?

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Financial Innovation 2022年第1期8卷 2289-2316页

作者： Louis t.W.Cheng Jack S.C.Poon Shaolong tang Jacqueline Wenjie Wang School of Business The Hang Seng University of Hong KongHong KongChina School of Accounting and Finance of the Hong Kong Polytechnic University Hong KongChina Division of Business and Management Beijing Normal University-Hong Kong Baptist UniversityUnited International CollegeZhuhaiChina

the literature shows that investor attention to customer–supplier disclosure increases when suppliers’information arrival is anticipated.Due to the widespread of city lockdowns in China and the implementation of social distancing to control the COVID-19 pandemic,investor attention to potential disruption of the supply chain spikes,leading to a price devaluation for firms with high supplier concentration risk.We find that a higher degree of supplier concentration is related to more serious stock price declines over the short-term and medium-term windows right after the Wuhan lockdown.this result lends support to the argument that the concentration risk of suppliers is a significant consideration for China stock market investors,especially under the potential financial distress at the firm level induced by the COVID-19 crisis.

关键词： COVID-19 Supplier concentration Supplier disclosure Stock price effect Industry neutral portfolio