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Nano Research 2024年第9期17卷 8627-8637页

作者： Shan-Fei wang Yangyang Li Haiyan wang Jin-Xia Liang Chun Zhu Botao Qiao School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

Oxide-supported metal single-atom catalysts(SACs)have exhibited excellent catalytic performance for water-gas shift(WGS)***,we report the single-atom catalyst Pt1/FeOx exhibits excellent medium temperature catalytic performance for WGS reactions by the density functional theory(DFT)calculations and experimental *** calculations indicate that H_(2)O molecules are easily dissociated at oxygen vacancies,and the formed*OH and*O are adsorbed on Pt1 single atoms and the adjacent O atoms,*** studying four possible reaction mechanisms,it is found that the optimal WGS reaction pathway is proceeded along the carboxyl mechanism(pathway III),in which the formation of*COOH intermediates can promote the stability of Pt1/FeOx SAC and the easier occurrence of WGS *** energy barrier of the rate-determining step during the entire reaction cycle is only 1.16 eV,showing the high activity for the medium temperature WGS reaction on Pt1/FeOx SAC,which was verified by experimental ***,the calculated turnover frequencies(TOFs)of CO_(2)and H_(2)formation on Pt1/FeOx at 610 K(337℃)can reach up to 1.14×10^(-3)s^(-1)·site^(-1)through carboxyl *** this work,we further expand the application potential of Pt1/FeOx SAC in WGS reaction.

关键词： water-gas shift(WGS)reaction single-atom catalyst(SAC) density functional theory(DFT) thermocatalysis

冀东蓟县群白云岩中锂资源的成因与赋存状态研究

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岩石学报 2023年第9期39卷 2761-2777页

作者：孙艳耿晓磊周炜智陈云飞李晓峰刘何凡赵保强王克冰中国地质科学院矿产资源研究所北京100037 中国地质大学(北京) 北京100083 河北省地质调查院石家庄050051

唐山丰润蓟县群雾迷山组中发现了Li含量达781×10^(-6)(折合Li 2O含量0.16%)的富锂白云岩,其厚度大、分布广,是重要的潜在沉积型锂资源。本文通过野外考察、样品分析测试等手段,对该区雾迷山组中锂的分布、成因和赋存状态进行了探讨,研... 详细信息

唐山丰润蓟县群雾迷山组中发现了Li含量达781×10^(-6)(折合Li 2O含量0.16%)的富锂白云岩,其厚度大、分布广,是重要的潜在沉积型锂资源。本文通过野外考察、样品分析测试等手段,对该区雾迷山组中锂的分布、成因和赋存状态进行了探讨,研究表明:该地区泥晶白云岩、泥质白云岩、白云质泥岩和泥岩样品中富集锂,白云岩、硅化白云岩及硅质岩不富集锂;锂的含量与伊利石含量存在显著相关性,指示伊利石可能为锂的主要赋存矿物;锂赋存位置为矿物间的非晶质伊利石等粘土矿物;样品中几乎不含吸附状态的锂,认为锂应该赋存在矿物晶格中呈类质同象状态;富锂样品和贫锂样品为同一源岩风化的产物;源岩(钙质泥岩)风化为锂富集提供稳定物质来源,含氧、干旱、浅水沉积环境有利于锂的富集。

关键词：冀东地区蓟县群富锂白云岩赋存状态沉积环境

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氨基磺酸催化甲醛和甲酸甲酯的偶联反应

石油化工 2005年第9期34卷 859-862页

作者：王克冰姚洁王越王公应中国科学院成都有机化学研究所

在釜式反应器中研究了氨基磺酸催化甲醛和甲酸甲酯的偶联反应,考察了反应温度、反应时间、原料配比、催化剂用量等因素对乙醇酸甲酯和甲氧基乙酸甲酯生成量的影响,得到最佳反应条件为:反应温度150～160℃、反应时间4 h、反应物料配比n(... 详细信息

在釜式反应器中研究了氨基磺酸催化甲醛和甲酸甲酯的偶联反应,考察了反应温度、反应时间、原料配比、催化剂用量等因素对乙醇酸甲酯和甲氧基乙酸甲酯生成量的影响,得到最佳反应条件为:反应温度150～160℃、反应时间4 h、反应物料配比n(甲醛):n(甲酸甲酯)=0.5、氨基磺酸催化剂的用量为甲酸甲酯质量的2.9%.在此条件下,乙醇酸甲酯和甲氧基乙酸甲酯的生成量最大,总生成量达到21.34mmol/g(以每克催化剂生成产物的物质的量计).与其它非硫酸型催化剂的性能相比,氨基磺酸的催化效果最佳.

关键词：氨荩磺酸甲醛甲酸甲酯乙醇酸甲酯甲氧基乙酸甲酯偶联反应催化

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关于国内外水电工程土地征收制度的研究

水利技术监督 2022年第9期30卷 89-93页

作者：谭哲武王克彬袁泉长江勘测规划设计研究有限责任公司湖北武汉430010

在我国水电工程建设中,征地移民是一项复杂的系统工程,直接关系到社会的稳定和工程建设的顺利推进,是急需解决的首要难题之一,对于从事海外水电工程建设而言更具困难和挑战。文章仅以尼泊尔国家的部分水电工程为研究背景,采用现场调研... 详细信息

在我国水电工程建设中,征地移民是一项复杂的系统工程,直接关系到社会的稳定和工程建设的顺利推进,是急需解决的首要难题之一,对于从事海外水电工程建设而言更具困难和挑战。文章仅以尼泊尔国家的部分水电工程为研究背景,采用现场调研和对比分析的方法,着重从土地所有制、土地征收方式和土地补偿标准三个方面对国内外水电工程土地征收制度进行对比分析和研究。研究结果表明尼泊尔土地征收制度与我国的有本质区别,在投资时应充分了解国外的征地移民政策,明确责任范围,做好风险分析和评估工作。

关键词：尼泊尔土地所有制征收方式补偿标准

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经尿道前列腺钬激光剜除术并发症的研究进展

中华腔镜泌尿外科杂志（电子版） 2022年第1期16卷 93-96页

作者：汪洋李志鹏王可兵深圳市前海蛇口自贸区医院泌尿外科广东518000 昆明医科大学第二附属医院泌尿外科云南650500

钬激光(Holmium:YAG laser)是一种多用途、安全高效的脉冲式激光,具有组织穿透度浅(0.4 mm)、脉冲持续时间短(0.25 ms)、瞬时峰值功率高(10 kW)等特点,加之波长(2140 nm)接近水的吸收峰值,其使用安全,具有对软组织极佳的切割效果以及强... 详细信息

钬激光(Holmium:YAG laser)是一种多用途、安全高效的脉冲式激光,具有组织穿透度浅(0.4 mm)、脉冲持续时间短(0.25 ms)、瞬时峰值功率高(10 kW)等特点,加之波长(2140 nm)接近水的吸收峰值,其使用安全,具有对软组织极佳的切割效果以及强大的碎石功能。自从1996年Gilling等[1]首次报道使用钬激光行前列腺切除术(holmium laser resection of the prostate,HoLRP)以来,逐渐广泛应用于临床,随着组织粉碎器技术的发展,1998年Gilling等[2]再次提出钬激光前列腺剜除术(holmium laser enucleation of the prostate,HoLEP)。

关键词：前列腺增生钬激光剜除术并发症

The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu Yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

Numerical Analysis of PRISM-PY Calculations for Hard-and Soft-Core Generic Polymer Models

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Chinese Journal of Polymer Science 2024年第4期42卷 532-543页

作者： Qiang wang Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N.

关键词： Generic polymer models Soft potentials Polymer reference interaction site model theory

Linear-Quadratic Pareto Cooperative Game for Mean-Field Backward Stochastic System

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Journal of Systems Science & Complexity 2024年第3期37卷 947-964页

作者： wang Yu School of Control Science and Engineering Shandong UniversityJinan 250061China

This paper focuses on a Pareto cooperative differential game with a linear mean-field backward stochastic system and a quadratic form cost functional. Based on a weighted sum optimality method, the Pareto game is equivalently converted to an optimal control problem. In the first place,the feedback form of Pareto optimal strategy is derived by virtue of decoupling technology, which is represented by four Riccati equations, a mean-field forward stochastic differential equation(MF-FSDE),and a mean-field backward stochastic differential equation(MF-BSDE). In addition, the corresponding Pareto optimal solution is further obtained. Finally, the author solves a problem in mathematical finance to illustrate the application of the theoretical results.

关键词： Backward stochastic differential equation linear-quadratic control mean-field Pareto optimality

Light People: Professor Fanglin Bao and his cover story

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Light(Science & Applications) 2024年第6期13卷 1015-1020页

作者： Ji wang School of Science Westlake UniversityHangzhouZhejiangPR China

Qu Yuan,a renowned ancient Chinese poet,once pondered in his work Heavenly Inquiry:“If the sun’s light is absent,from where does the radiance of the Hero Flower emanate?”The ability to see clearly in the darkest of nights has long been a sought-after magical power by *** holds not only immense technological significance for computer vision and remote sensing but also profound implications for transcending the dichotomy between day and night in our daily *** Fanglin Bao from Westlake University has made significant breakthroughs in this field,bringing us closer to a world where we can transform night into *** groundbreaking research on Heat-Assisted Detection and Ranging(HADAR)and night vision was featured as the cover story in Nature on July 26,2023.

关键词： bringing breakthrough holds

A multi-source information fusion layer counting method for penetration fuze based on TCN-LSTM

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Defence Technology（防务技术） 2024年第3期33卷 463-474页

作者： Yili wang Changsheng Li Xiaofeng wang Nanjing University of Science and Technology Nanjing 210094JiangsuChina State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ferromagnetic materials,thereby posing challenges in accurately determining the number of *** address this issue,this research proposes a layer counting method for penetration fuze that incorporates multi-source information fusion,utilizing both the temporal convolutional network(TCN)and the long short-term memory(LSTM)recurrent *** leveraging the strengths of these two network structures,the method extracts temporal and high-dimensional features from the multi-source physical field during the penetration process,establishing a relationship between the multi-source physical field and the distance between the fuze and the target plate.A simulation model is developed to simulate the overload and magnetic field of a projectile penetrating multiple layers of target plates,capturing the multi-source physical field signals and their patterns during the penetration *** analysis reveals that the proposed multi-source fusion layer counting method reduces errors by 60% and 50% compared to single overload layer counting and single magnetic anomaly signal layer counting,*** model's predictive performance is evaluated under various operating conditions,including different ratios of added noise to random sample positions,penetration speeds,and spacing between target *** maximum errors in fuze penetration time predicted by the three modes are 0.08 ms,0.12 ms,and 0.16 ms,respectively,confirming the robustness of the proposed ***,the model's predictions indicate that the fitting degree for large interlayer spacings is superior to that for small interlayer spacings due to the influence of stress waves.

关键词： Penetration fuze Temporal convolutional network(TCN) Long short-term memory(LSTM) Layer counting Multi-source fusion