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New potential-energy functions for Cu, Ag and Au solids and their applications to computer simulations on metallic surfaces

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Science China Chemistry 1998年第6期41卷 566-574页

作者：刘新厚甄珍 h.cox J.N.Murrell 1. Institute of Photographic Chemistry Chinese Academy of Sciences 100101 Beijing China 2. School of Chemistry Physics and Environment Science University of Sussex BN1 9QJ Brighton U.K.

A set of potential energy functions for noble metals: copper, silver and gold crystals has been derived. New potential energy functions reproduce not only bulk properties, including elastic constants, phonon dispersion curves, cohesive energies, etc., but also surface behaviors of the metals. New potential energy functions have been used to simulate the surface properties of the three noble metals, computer simulations are in good agreement with experimental results.

关键词： potential function noble metal surface computer simulation.

贵金属新分析势能面及在金属表面计算机模拟中的应用

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中国科学（B辑） 1999年第3期29卷 280-288页

作者：刘新厚甄珍 h.cox J.N.Murrell 中国科学院感光化学研究所北京100101 SchoolofChemistryPhysicsandEnvironmentalScience UniversityofSussex

导出了一组贵金属 :铜、银、金晶体新的分析势能面 .新导出的分析势能面不仅精确地描述了该族金属元素晶体的宏观性质 ,如 :弹性模量、声子色散曲线、原子化能、表面能等 ,也给出这些金属表面性质正确的描述 .利用新分析势能面对贵金属... 详细信息

导出了一组贵金属 :铜、银、金晶体新的分析势能面 .新导出的分析势能面不仅精确地描述了该族金属元素晶体的宏观性质 ,如 :弹性模量、声子色散曲线、原子化能、表面能等 ,也给出这些金属表面性质正确的描述 .利用新分析势能面对贵金属晶体表面性质进行了计算机模拟 ,模拟结果与实验数据十分吻合 .

关键词：势能面贵金属表面模拟计算机模拟表面性质

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自适应波束形成中的敏感性分析

声学技术 1975年第2期 86-103页

作者： h.cox 向大威美国加利福尼亚大学海洋物理实验室及斯克里普斯海洋研究所

一、引言通过 Bryn 和 Mermoz 的工作,最佳基阵的理论已为水声界所熟知。他们的工作与其他检测及估值问题的关系已在文献中讨论过了。最佳基阵处理系统利用信号场和噪声场的详细信息。由于这些信息在事先不能确切知道,因此人们自然就想... 详细信息

一、引言通过 Bryn 和 Mermoz 的工作,最佳基阵的理论已为水声界所熟知。他们的工作与其他检测及估值问题的关系已在文献中讨论过了。最佳基阵处理系统利用信号场和噪声场的详细信息。由于这些信息在事先不能确切知道,因此人们自然就想到自适应波束形成器,自适应波束形成器通过某种现场的测量来不断地调节其参数。正由于自适应处理器是不断调节的,因此很自然会问:如果信号场、噪声场及系统参数相对于它们的假设值或估计值有一个小的变化,那末自适应处理器的性能对这些变化的敏感性有多大?

关键词：波束形成器归一化信号响应矩阵数学分析信号分量声学仪器基阵空间白噪声波束指向各向同性噪声白噪声增益

Best Bounds on Measures of Risk and Probability of Ruin for Alpha Unimodal Random Variables When There Is Limited Moment Information

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Applied Mathematics 2016年第8期7卷 765-783页

作者： Patrick L. Brockett Samuel h.cox, Jr. Richard D. MacMinn Bo Shi Department of Information Risk and Operations Management University of Texas Austin TX USA Robinson College of Business Georgia State University Atlanta GA USA Center for Risk Management University of Texas Austin TX USA National Chengchi University Taipei City College of Business and Technology Morehead State University Morehead KY USA

This paper presents explicit formulae giving tight upper and lower bounds on the expectations of alpha-unimodal random variables having a known range and given set of moments. Such bounds can be useful in ordering of random variables in terms of risk and in PERT analysis where there is only incomplete stochastic information concerning the variables under investigation. Explicit closed form solutions are also given involving alpha-unimodal random variables having a known mean for two particularly important measures of risk—the squared distance or variance, and the absolute deviation. In addition, optimal tight bounds are given for the probability of ruin in the collective risk model when the severity distribution has an alpha-unimodal distribution with known moments.

关键词： Alpha-Unimodal Bounds on Risk Measures Partial Moment Knowledge Actuarial Applications Measures of Dispersion

Nuclear Processes in Dark Interstellar Matter of h(0) Decrease the hope of Migrating to Exoplanets

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Space(Science & Technology) 2021年第1期2021卷 127-132页

作者： leif holmlid Department of Chemistry and Molecular Biology University of GothenburgSE-41296 GöteborgSweden

It is still generally assumed that interstellar travel will be possible after purely technical development and thus that mankind can move to some suitable exoplanet when ***,recent research indicates this not to be the case,since interstellar space is filled with enough ultradense hydrogen h(0)as stable condensed dark matter(holmlid,Astrophysical Journal 2018)to make interstellar space travel at the required and technically feasible relativistic velocities(holmlid et al,Acta Astronautica 2020)almost impossible.h(0)can be observed to exist in space from the so-called extended red emission(ERE)features observed in space.A recent review(holmlid et al.,Physica Scripta 2019)describes the properties of h(0).h(0)gives nuclear processes emitting kaons and other particles,with kinetic energies even above 100 MeV after induction for example by fast particle(spaceship)*** high particle energies give radiative temperatures of 12000 K in collisions against a solid surface and will rapidly destroy any spaceship structure moving into the h(0)clouds at relativistic *** importance of preserving our ecosystem is pointed out,since travel to suitable exoplanets may be *** possibilities of instead clearing interstellar space from h(0)are discussed,eventually providing tunnels suitable for relativistic interstellar *** regions with low intensity of ERE could even be a way to identify space-cleaning activities and thus to locate earlier spacetravelling civilizations.

关键词： relativistic instead eventually

An approach of the internal friction-dependent temperature changes for conventional and pure biogenic lubricating greases

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Friction 2024年第4期12卷 780-795页

作者： leif AhME Erik KUhN MiguelÁngel DELGADO Department of Mechanical Engineering and Production Management Hamburg University of Applied SciencesHamburg 20099Germany Department of Chemical Engineering Research in Product Technology and Chemical Processes(Pro2TecS)University of HuelvaHuelva 21071Spain

This work investigated the temperature changes inside the bulk of lubricating greases under controlled high-shear stress conditions(250-500 s-1).For this purpose,a newly developed temperature-measuring cell called Calidus was successfully *** temperature changes(ΔT)have been related to the greases'components(thickener,base oil-type,and composition)and the structural degradation of the lubricating ***,a theoretical approach was proposed for calculating the internal temperature change of lubricating greases during shear *** greases showed an internal temperature profile characterised by a sudden rise inΔT within the first 4 h from starting the test and subsequentΔT decay until it reaches the steady state ***,it was found that greases C1 and C5,formulated with lithium and calcium soap,respectively,with different soap content(16.1 wt%and 9.7 wt%,respectively),but the same base castor oil,showed the highest value of the maximumΔT,c.a.3.2 K,and the most drastic drop ofΔ*** greases showed both the highest specific densities and heat *** addition,they showed the lowest ratio of expended energies(Rtee),which means more structural degradation in the stressed *** the contrary,the grease C3,with 13 wt%of Li-soap but the lowest base oil's viscosity,showed the lowest maximumΔT and the temperature profile was characterised by a moderate variation ofΔT along the *** biogenic grease B3 developed a low-temperature change in the group of pure bio-genic greases close to grease C3.

关键词： shear-induced structural degradation rheology temperature measurements lubricating greases density lubricating greases specific heat capacities

The Siberian moth(Dendrolimus sibiricus),a pest risk assessment for Norway

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Forest Ecosystems 2020年第4期7卷 635-645页

作者： Daniel Flø Trond Rafoss Michael Wendell leif Sundheim Norwegian Institute of Bioeconomy Research Høgskoleveien 71433ÅsNorway The Norwegian Scientific Committee for Food and Environment Sandakerveien 24 C0473 OsloNorway

Background:The Siberian moth(Dendrolimus sibiricus)is a serious pest of conifers in Russia,Northern Kazakhstan,Mongolia and *** western border of the pest’s distribution in Russia is disputed,but it is present west of the 60th meridian *** pest has the potential to defoliate a wide range of ***:The pest is not present in Norway or other European countries,except *** spread and human mediated transport are potential pathways for the *** mediated pathways considered are:Living trees for planting,coniferous wood in the rough and foliage and *** has been no import of living trees from Russia to Norway during the past 30 years,and there is currently no import of coniferous wood commodities containing bark from areas,where *** ***:The probability of *** entry by natural spread is unlikely,mainly because of the geographical distance and the partial sea barriers between Norway and the infested *** probability of entry by human mediated pathways is unlikely due to the very limited volume of the *** the pest enter Norway,the probability of establishment and spread is unlikely,due to the suboptimal climatic conditions,and the fact that the two dominant conifers in the country,Norway spruce(Picea abies)and Scots pine(Pinus sylvestris),are intermediate and poor hosts,*** potential damage,should *** enter Norway,is considered low.

关键词： Lepidoptera Invasive species Geographical distribution Forest pest

Equal Sex Ratios of a Marine Green Alga, Bryopsis plumosa

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Journal of Integrative Plant Biology 2008年第6期50卷 648-652页

作者： Tatsuya Togashi Paul Alan cox Marine Biosystems Research Center Chiba University Institute for Ethnomedicine Box 3464 Jackson Hole Wyoming 83001 USA Institute for Ethnomedicine Box 3464 Jackson Hole

By finding some important culture conditions as below, we succeeded in experimentally controlling the whole life history of a dioecious marine green alga, Bryopsis plumosa （hudson） C. Agardh. In this study, we focused on the primary and secondary sex ratios （i.e. at inception and maturity） using these culture techniques. Gametogenesis was induced by culturing haploid gametophytes with Provasoli＇s enriched seawater （PES） medium under a 14：10 h light： dark cycle at 14 ℃. Formed zygotes grew into diploid sporophytes, which were cultured for 3 months with PES medium under a 14：10 h light ： nbsp;dark cycle at 18℃. Then they were transferred into Schreiber medium and cultured under a 10：14 h light： dark cycle at 22℃. Within 1 week, zoosporogenesis was observed. Zoospores were released within a couple of days. Each zoospore soon germinated and grew into a unisexual gametophyte. The primary sex ratio was examined in gametophytes that originated from a single sporophyte. The secondary sex ratio was studied in the field. Both were estimated as 1：1. Synchronized meiotic cell divisions might occur during zoosporogenesis dividing each sex-determining factor evenly among zoospores. Given the equal sex ratio at maturity, there seems to be no environmental factor that differentially affects the survival of male or female gametophytes in nature.

关键词： algal culture Bryopsis green algae life history sex ratio.

Radical Interaction between Carotenoids and Plant Phenols in Relation to Antioxidant Synergism

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Radical Interaction between Carotenoids and Plant Phenols in...