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Metal-to-insulator transition in platinum group compounds

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Rare Metals 2024年第8期43卷 3460-3474页

作者： yu-Xuan Xia Jian-gang He Nuo-Fu Chen Ji-Kun Chen School of New Energy North China Electric Power UniversityBeijing102206China School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China Key Laboratory of Advanced Materials and Devices for PostMoore Chips(Ministry of Education) School of Materials Science and EngineeringJniversity of Science and Technology BeijingBeijing 100083China

The metal-to-insulator transition(MIT) as usually achieved in 3d-orbital transitional metal(TM) compounds opens up a new paradigm in correlated electronics via triggering abrupt variations in their transportation *** to such 3d-orbital TM compounds,the MIT within the platinum group(Pg) element compounds based on the 4d-and 5d-orbital configurations is more complicated,owing to their elevation in the spinorbit coupling and meanwhile weakened intra-atomic Coulomb *** brings in a new freedom to regulate the balance in their metallic or semiconductive orbital configurations,while their MIT properties can be potentially combined with their spintronic properties to enable new electronic ***,we review the electronic transport and MIT behaviors within the existing family of Pg-containing compounds,particularly those showing first-order MIT behaviors that can be useful in correlated *** is also hoped that summarizing the presently reported Pg-containing MIT compounds will lead to the discovery of more new material families and/or new mechanisms associated with the Pg-containing compounds showing MIT properties.

关键词： Metal-to-insulator transition Platinum group compounds Electron correlation Spin-orbital coupling

How interfacial electron-donating defects influence the structure and charge of gold nanoparticles on TiO_(2)support

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Nano Research 2024年第7期17卷 5965-5974页

作者： Guang-Jie Xia yu Fu Wei Cao Jun Li Yang-gang Wang Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and TechnologyShenzhen 518055China School of Physical Sciences Great Bay UniversityDongguan 523000China Department of Chemistry Tsinghua UniversityBeijing 100084China

The reduction degree of TiO_(2)support is critical to the performances of metal *** many previous theoretical calculations,only the bridge oxygen vacancy(Ov)was considered as the electron-donating defect on reduced rutile TiO_(2)(r-TiO_(2−x))***,titanium adatoms(Tiad.),oxidized titanium islands(***),and acid hydroxyls(ObrH)also exist at the metal/support *** conducting density functional theory(DFT)calculations and ab initio molecular dynamics(AIMD)simulations,we compared r-TiO_(2−x)surfaces with Ov,Tiad.,***,and ObrH sites loaded with Au nanoparticles(NPs).The results showed the Au NPs were oxygen-phobic but titanium-philic,resulting in wetting of Ov and *** short contact with *** and *** Bader charges of Au NPs(QM)showed a good linear relationship with the ideal number of donating electrons(Ne)from the defective sites(QM=−KeNe+QM,S),demonstrating the intrinsic electron allocation at the *** Ov,Tiad.,and *** exhibited similar slopes(Ke),relatively steeper than that of *** means in the scope of Au NP charge state,the *** *** have a close electron-donating ability with Ov,but the ObrH donates relatively fewer *** linear relationship can be extended approximately to other *** higher the metal work function,the steeper the Ke for easier electron donation from defective *** stronger the metal oxygen affinity,the more positive the intercept(QM,S).That explains the easy generation of metallic or negative Pt and Au NPs on r-TiO_(2−x),but hard for Cu and Zn in *** provides theoretical guidance for regulating the charge of metal NPs over TiO_(2−x)supports.

关键词： metal-support interaction titanium oxide oxygen vacancy surface hydroxyl titanium adatom

α-clustering effect on flows of direct photons in heavy-ion collisions

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Nuclear Science and Techniques 2021年第6期32卷 122-132页

作者： Chen-Zhong Shi yu-gang Ma Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China University of the Chinese Academy of Sciences Beijing 100080China

In this study,we reconstruct theγ-photon energy spectrum,which is in good agreement with the experimental data of ^(86)Kr+^(12)C at E/A=44 Me V within the framework of the modified EQMD *** directed and elliptic flows of free protons and direct photons were investigated by considering theα-clustering structure of ^(12)*** with free protons,direct photon flows provide clearer information about the early stage of a nuclear *** difference in the collective flows between different configurations of ^(12)C is observed in this *** indicates that the collective flows of direct photons are sensitive to the initial ***,theγbremsstrahlung process might be taken as an alternative probe to investigate theα-clustering structure in a light nucleus from heavy-ion collisions within the Fermienergy region.

关键词： Nuclear reaction Direct photon Collective flow α-clustering configuration

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强风区高铁刚性吊弦系统接触网振动研究

铁道工程学报 2023年第6期40卷 93-98页

作者：余纲中铁第一勘察设计院集团有限公司西安710043

研究目的:受电弓高速通过刚性吊弦时,会引起刚性吊弦与绝缘套筒的分离,产生吊弦力,引起接触网振动,叠加风荷载后振动加剧,造成吊弦磨损严重甚至断裂,也会影响弓网关系。为确认强风区高速铁路刚性吊弦设计运维的关键点,动车组达速运行条... 详细信息

研究目的:受电弓高速通过刚性吊弦时,会引起刚性吊弦与绝缘套筒的分离,产生吊弦力,引起接触网振动,叠加风荷载后振动加剧,造成吊弦磨损严重甚至断裂,也会影响弓网关系。为确认强风区高速铁路刚性吊弦设计运维的关键点,动车组达速运行条件下接触网系统可适应的最大风速,以广深港铁路为研究对象,运用有限元动力学方程组建立仿真模型,仿真计算吊弦力的数字特征及离线率;利用Davenport顺向谱和Panofsky竖向谱构造模拟脉动风速,研究不同速度及风速条件下接触网弓网耦合关系,寻求强风区域刚性吊弦接触网系统安全运营边界和设备薄弱点。研究结论:(1)吊弦力和风荷载共同作用下,离定位点最近的吊弦受冲击及振动最大,设计时应考虑设备局部加强,运维也应重点关注;(2)风速越大,振动增大趋势越显著,风速大于20 m/s后,弓网关系恶化速度显著加快;(3)风速大于20 m/s,弓网动态性能超出标准要求,后弓问题尤为突出,无法满足动车组时速300 km运行要求;(4)本研究结果可为强风区刚性吊弦系统接触网设计、运维及大风天气行车组织提供借鉴和参考。

关键词：刚性吊弦接触网振动吊弦力离线率强风

New insights into the mechanism of reactive adsorption desulfurization on Ni/ZnO catalysts:Theoretical evidence showing the existence of interfacial sulfur transfer pathway and the essential role of hydrogen

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Petroleum Science 2023年第5期20卷 3240-3250页

作者： Hou-yu Zhu Nai-You Shi Dong-yuan Liu Rui Li Jing-gang yu Qi-Tang Ma Tu-Ya Li Hao Ren yuan Pan yun-Qi Liu Wen-yue Guo School of Materials Science and Engineering China University of Petroleum(East China)Qingdao266580ShandongChina State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao266580ShandongChina

As well known in the petroleum industry and academia,Ni/ZnO catalysts have excellent desulfurization ***,the sulfur transfer mechanism of reactive adsorption desulfurization(RADS)that occurs on Ni/ZnO catalysts remains ***,a periodic Ni nanorod supported on ZnO slab was built to represent the Ni/ZnO system,and density functional theory calculations were performed to study the sulfur transfer process and the role of H_(2)within the *** results elucidate that the direct solid-state diffusion of S from Ni to interfacial oxygen vacancies(Ov)is more favorable than the hydrogenation of S to SH/H_(2)S on Ni and the subsequent H_(2)S desorption,and accordingly,H_(2)O is produced on Ni rather than on *** initio thermodynamics analysis shows that the hydrogen atmosphere applied in preparing Ni/ZnO catalysts greatly promotes the O_(v)formation on ZnO surface,which accounts for the presence of interfacial O_(v)in freshly prepared *** RADS condition,hydrogenation of interfacial O atoms to form O-H groups facilitates the reverse spillover of these lattice O atoms from ZnO to Ni,accompanied with the interfacial O_(v)*** contrast to the classic S transfer mechanism via H_(2)S,the present work clearly demonstrates that the interfacial S transfer is a feasible reaction pathway in the RADS *** importantly,the existence of interfacial O_(v)is an essential prerequisite for this interfacial S diffusion,and H_(2)plays a key role in facilitating the O_(v)formation.

关键词： Reactive adsorption desulfurization Ni/ZnO Interface Sulfur transfer Density functional theory

基于Drude模型ITO薄膜性能及工艺控制分析

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玻璃 2024年第8期51卷 1-6页

作者：王三昭余刚石攀孟政刘启蒙汪洪中建材光芯科技有限公司枣庄277100 中国建筑材料科学研究总院有限公司北京100024

利用离子辅助电子束蒸发技术制备锡掺杂氧化铟薄膜,参考“第四范式”研究思路,根据薄膜光学性质特点建立以Drude振子为核心的光学模型,从模型参数入手,分析载流子浓度、迁移率对光学性能影响,得出提高载流子迁移率能够同步提升薄膜产品... 详细信息

利用离子辅助电子束蒸发技术制备锡掺杂氧化铟薄膜,参考“第四范式”研究思路,根据薄膜光学性质特点建立以Drude振子为核心的光学模型,从模型参数入手,分析载流子浓度、迁移率对光学性能影响,得出提高载流子迁移率能够同步提升薄膜产品的光、电性能。总结分析文献报道中的主要成果,提出性能提升工艺方案,样品经验证载流子迁移率由6.3 cm^(2)·V^(-1)·s^(-1)提高到18.3 cm^(2)·V^(-1)·s^(-1),厚度由315.5 nm减薄到155.2 nm情况下,面电阻由50.1 Ω/□减小到26.2Ω/□。

关键词： ITO薄膜载流子浓度迁移率光学常数光学模型

MARKETING OBJECTIVES OF RETAILERS WITH DIFFERENTIATED GOODS:AN EVOLUTIONARY PERSPECTIVE

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Journal of Systems Science and Systems Engineering 2006年第3期15卷 359-374页

作者： Tiaojun XIAO gang yu School of Management Science and Engineering Nanjing University Nanjing Jiangsu 210093 China Department of Management Science and Information Systems McCombs School of Business The University of Texas at Austin Austin Texas 78712-1175 USA

In the real world, revenue maximization behavior may prevail in various markets. To understand this phenomenon, we develop a two-population model with two-vertically integrated channels. Every channel consists of one manufacturer and many （a sufficiently large number of） retailers that sell products in different markets by adopting pure marketing objective strategies： profit maximization and revenue maximization. We study the marketing objective behaviors in the quantity-setting duopoly and the price-setting duopoly situations respectively from an indirect evolutionary point of view. In the quantity-setting duopoly situation, we find that whether the equilibrium is an evolutionarily stable strategy depends on the type of strategic iateraction （substitutes or complements）, relative unit cost, market scale, etc. We extend it to the case with continuous preferences. We argue that revenue maximization may be an evolutionarily stable strategy and profit maximization strategy may be unstable. Under proper conditions, revenue maximization behavior can coexist with profit maximization behavior. In the price-setting duopoly situation with linear demand functions, we find that profit maximization is always an evolutionarily stable strategy and revenue maximization behavior will gradually become extinct. The extended model has a similar result but the retailers may compromise the two pure strategies.

关键词： Evolutionary game theory ESS marketing objective complements and substitutes

Sequential bowel necrosis and large gastric ulcer in a patient with a ruptured femoral artery:A case report

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2337-2342页

作者： Peng Wang Ting-gang Wang An-Yong yu Department of Emergency The Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina

BACKGROUND Severe bleeding as a result of a major vascular injury is a potentially fatal event commonly observed in the emergency *** necrosis and gastric ulcers secondary to ischemia are rare due to their rich blood *** this case,we present the case of a patient who was treated successfully following rupture of his femoral artery resulting in bowel necrosis and an unusually large gastric *** SUMMARY A 28-year-old male patient sustained a knife stab wound to the right thigh,causing rupture of his femoral artery and leading to massive *** underwent cardiopulmonary resuscitation and received a large blood *** surgeries confirmed bowel necrosis,and jejunostomy was *** necrotic intestine was removed,the remaining intestine was anastomosed,and the right thigh was *** three surgeries,the patient's overall condition gradually improved,and the patient was discharged from the ***,one day after discharge,the patient was admitted again due to dizziness and melena,and a gastroduodenoscopy revealed a giant banded *** 2 weeks of treatment,the ulcer had decreased in size without *** months after the last surgery,enterostomy and reintroduction surgery were *** patient was fitted with a right lower limb prosthesis one year after *** 3 years of follow-up,the patient did not complain of *** Trauma department physicians need to be aware of the possible serious complications involving the abdomen of trauma patients with massive bleeding.

关键词： Bowel necrosis Gastric ulcer Trauma Femoral artery rupture Ischemia Case report

一次性电子软镜和常规可重复性软镜对输尿管上段结石患者肾功能和创伤程度的影响及术后复发的危险因素研究

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中国内镜杂志 2024年第7期30卷 31-38页

作者：喻敏李强黄东红余刚白健李健玮郑建辉梁思重黄耀光中山火炬开发区人民医院泌尿外科广东中山528437

目的探讨一次性电子软镜和常规可重复性软镜对输尿管上段结石患者肾功能和血清前列腺素E2(PGE2)、5-羟色胺(5-HT)水平的影响,并分析输尿管软镜碎石术(RIRS)治疗输尿管上段结石术后复发的影响因素。方法选取2022年3月-2023年3月该院收治... 详细信息

目的探讨一次性电子软镜和常规可重复性软镜对输尿管上段结石患者肾功能和血清前列腺素E2(PGE2)、5-羟色胺(5-HT)水平的影响,并分析输尿管软镜碎石术(RIRS)治疗输尿管上段结石术后复发的影响因素。方法选取2022年3月-2023年3月该院收治的输尿管上段结石患者114例,按随机数表法分为观察组(n=57)和对照组(n=57)。观察组使用一次性电子输尿管软镜行RIRS治疗,对照组采用常规可重复性输尿管软镜行RIRS治疗,比较两组患者手术情况。于术前和术后24 h,检测患者肾功能指标[血尿素氮(BUN)、肌酐(Cr)、半胱氨酸蛋白酶抑制剂C(CysC)]、PGE2和5-HT水平。术后随访6个月,比较两组患者术后并发症和复发情况。根据术后有无复发进行分组,收集复发组和未复发组的病历资料,并对术后复发的危险因素进行统计分析。结果观察组和对照组手术时间、术中出血量、一次性结石清除率和住院时间比较,差异均无统计学意义(P>0.05)。两组患者术后血清BUN、Cr、CysC、PGE2和5-HT水平较术前明显升高,差异均有统计学意义(P0.05)。观察组术后并发症总发生率和复发率分别为3.51%和15.79%,对照组分别为12.28%和21.05%,两组患者比较,差异均无统计学意义(P>0.05)。复发组体重指数(BMI)、术后残留结石率和术后泌尿系感染率明显高于未复发组,差异均有统计学意义(P<0.05)。多因素Logistic回归分析显示,在校正性别、年龄、病程、结石最大直径、结石数目、结石位置和手术方式等混杂因素后,术后残留结石和术后泌尿系感染是RIRS治疗输尿管上段结石术后复发的独立危险因素(P<0.05)。结论一次性电子软镜和常规可重复性软镜在输尿管上段结石的治疗中,均能取得满意疗效,这两种软镜均可对患者的肾功能、血清PGE2和5-HT水平产生一定影响,且术后均存在一定的复发风险。术后残留结石和术后泌尿系感染是RIRS治疗输尿管上段结石术后复发的独立危险因素。

关键词：一次性输尿管上段结石输尿管软镜碎石术(RIRS) 肾功能前列腺素E2(PEG2) 5-羟色胺(5-HT) 复发危险因素