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Fabrication strategies of porous precious-metal-free bifunctional electrocatalysts for overall water splitting:Recent advances

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Green Energy & Environment 2021年第5期6卷 620-643页

作者： Jin-Tao Ren Yali yao zhong-Yong Yuan Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Institute of New Catalytic Materials ScienceSchool of Materials Science and EngineeringNankai UniversityTianjin300350China Institute for the Development of Energy for African Sustainability College of ScienceEngineering and TechnologyUniversity of South AfricaJohannesburgSouth Africa

Electrocatalytic water splitting using power generated from renewable energy to produce hydrogen has been considered as one of the more attractive approach to alleviate the problems of energy crisis and environmental *** of the biggest challenges for the large-scale application of water electrolysis is the searching of the low cost electrocatalysts with high and stable activity toward both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).The well-developed porous features of materials synthesized from the earth abundant elements endow them with the enhanced mass transfer and improved electronic interconnection during electrochemical reactions,resulting in the excellent electrocatalytic performance for both OER and ***,this review focuses on the recent development of innovation strategies for the fabrication of porous non-noble-metal materials including heteroatom-doped carbon-based and transition metal(mainly Co,Ni,and Fe)-based materials as efficient electrocatalysts for overall water ***,a detailed discussion of the structure–activity correlation gives an insight on the origin of the high electrocatalytic performance of porous materials obtained from different strategies,and provides guidance for future design and preparation of highly efficient electocatalysts based on non-precious carbon or metal materials for overall water splitting.

关键词： Electrocatalysis Porous materials Hydrogen evolution Oxygen evolution Overall water splitting

ON SMOOTH LU DECOMPOSITIONS WITH APPLICATIONS TO SOLUTIONS OF NONLINEAR EIGENVALUE PROBLEMS

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Journal of Computational Mathematics 2010年第6期28卷 745-766页

作者： hua Dai zhong-Zhi Bai Department of Mathematics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

We study the smooth LU decomposition of a given analytic functional A-matrix A（A） and its block-analogue. Sufficient conditions for the existence of such matrix decompositions are given, some differentiability about certain elements arising from them are proved, and several explicit expressions for derivatives of the specified elements are provided. By using these smooth LU decompositions, we propose two numerical methods for computing multiple nonlinear eigenvalues of A（A）, and establish their locally quadratic convergence properties. Several numerical examples are provided to show the feasibility and effectiveness of these new methods.

关键词： Matrix-valued function Smooth LU decomposition Pivoting Nonlinear eigenvalue problem Multiple eigenvalue Newton method.

Self-Learning and Its Application to Laminar Cooling Model of Hot Rolled Strip

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Journal of Iron and Steel Research International 2007年第4期14卷 11-14页

作者： GONG Dian-yao XU Jian-zhong PENG Liang-gui WANG Guo-dong LIU Xiang-hua State Key Laboratory of Rolling Technology and Automation Northeastern University Shenyang 110004 Liaoning China

The mathematical model for online controlling hot rolled steel cooling on run-out table （ROT for abbreviation） was analyzed, and water cooling is found to be the main cooling mode for hot rolled steel. The calculation of the drop in strip temperature by both water cooling and air cooling is summed up to obtain the change of heat transfer coefficient. It is found that the learning coefficient of heat transfer coefficient is the kernel coefficient of coiler temperature control （CTC） model tuning. To decrease the deviation between the calculated steel temperature and the measured one at coiler entrance, a laminar cooling control self-learning strategy is used. Using the data acquired in the field, the results of the self-learning model used in the field were analyzed. The analyzed results show that the self-learning function is effective.

关键词： laminar cooling hot rolled strip self-learning process control model

ON EIGENVALUE BOUNDS AND ITERATION METHODS FOR DISCRETE ALGEBRAIC RICCATI EQUATIONS

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Journal of Computational Mathematics 2011年第3期29卷 341-366页

We derive new and tight bounds about the eigenvalues and certain sums of the eigenvalues for the unique symmetric positive definite solutions of the discrete algebraic Riccati equations. These bounds considerably improve the existing ones and treat the cases that have been not discussed in the literature. Besides, they also result in completions for the available bounds about the extremal eigenvalues and the traces of the solutions of the discrete algebraic Riccati equations. We study the fixed-point iteration methods for com- puting the symmetric positive definite solutions of the discrete algebraic Riccati equations and establish their general convergence theory. By making use of the Schulz iteration to partially avoid computing the matrix inversions, we present effective variants of the fixed-point iterations, prove their monotone convergence and estimate their asymptotic convergence rates. Numerical results show that the modified fixed-point iteration methods are feasible and effective solvers for computing the symmetric positive definite solutions of the discrete algebraic Riccati equations.

关键词： Discrete algebraic Riccati equation Symmetric positive definite solution Eigenvalue bound Fixed-point iteration Convergence theory.

Quantum McKay Correspondence for Disc Invariants of Toric Calabi–Yau 3-orbifolds

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Acta Mathematica Sinica,English Series 2015年第1期31卷 29-34页

作者： hua-zhong KE Jian ZHOU Department of Mathematical Sciences Tsinghua University

We announce a result on quantum McKay correspondence for disc invariants of outer legs in toric Calabi-Yau 3-orbifolds, and illustrate our method in a special example [C^3/Z5（1, 1, 3）].

关键词： Quantum McKay correspondence disc invariants open mirror symmetry

Supercritical carbon dioxide as a new working medium for pneumatic launch:A theoretical study

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Defence Technology（防务技术） 2021年第4期17卷 1296-1306页

作者： Hong-xin yao Xue-zhong Wei Hong Ye Department of Thermal Science and Energy Engineering University of Science and Technology of ChinaHefei230027People’s Republic of China

Compared with the conventionally gaseous or liquid working media,the specific internal energy of supercritical carbon dioxide(SCD)is higher at the same temperature and pressure,and the critical temperature of carbon dioxide is close to room temperature,making SCD a potential new working medium for pneumatic *** analyze the feasibility of this conception,an analytical model of a pneumatic catapult is established on basis of the conservations of mass and *** model consists of a high-pressure chamber and a low-pressure chamber connected by multiple valves,and there is a movable piston in the low-pressure chamber that can push an aircraft to *** effects of the launch readiness state of SCD in the high-pressure chamber,the initial volume of the low-pressure chamber and the valve control on the movement of the aircraft are *** is found that there is a restrictive relation between the temperature and pressure of the launch readiness state of SCD,i.e.,there is a maximum allowable launch readiness pressure when the launch readiness temperature is *** this restrictive relation is not satisfied,the working medium in the low-pressure chamber will drop to its triple point within a few milliseconds,leading to a launch *** to this restrictive relation,there is an optimal launch readiness state of SCD with the highest working capacity for any allowable launch readiness *** pressure of the low-pressure chamber will decrease significantly as the initial volume increases,leading to a decreased acceleration of the *** acceleration can be controlled below a critical value by a designed sequential blasting technique of multiple *** calculated results show that a 500 kg aircraft can be accelerated from 0 to 58 m/s in 0.9 s with 36 kg of carbon *** research provides a new technique for the controllable cold launch of an aircraft.

关键词： Pneumatic launch Supercritical carbon dioxide Restrictive relation of the launch readiness state Optimal launch readiness state High working capacity

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植物激素对棉花蕾铃脱落的调控研究进展

作物学报 2025年第1期51卷 1-29页

作者：谢章书谢学方屠小菊刘爱玉董合忠周仲华湖南农业大学农学院/作物生理与分子生物学教育部重点实验室湖南长沙410128 中国热带农业科学院橡胶研究所海南海口571101 山东省农业科学院经济作物研究所山东济南250000

棉花蕾铃脱落是一个普遍存在的现象,有对逆境环境胁迫的主动适应性脱落,也有因品种遗传特性、环境条件、栽培措施以及生物和非生物胁迫被动的受损脱落。蕾铃脱落直接影响着棉花的产量,国内外现有公开报道多集中于20世纪50、60年代关于... 详细信息

棉花蕾铃脱落是一个普遍存在的现象,有对逆境环境胁迫的主动适应性脱落,也有因品种遗传特性、环境条件、栽培措施以及生物和非生物胁迫被动的受损脱落。蕾铃脱落直接影响着棉花的产量,国内外现有公开报道多集中于20世纪50、60年代关于乙烯和脱落酸对棉花蕾铃脱落影响的初步发现。结合其他植物的研究结果来看,蕾铃脱落似乎与生长素、赤霉素和细胞分裂素等促生长类激素的下降以及乙烯和脱落酸等抑制生长类激素的升高密切相关,激素在植物体内不仅介导新陈代谢过程,还协调着与信号通路相关的调控因子,在脱落过程中起着关键作用。本文从植物激素调控入手,综述了近年来包括脱落区形成和作用的分子调控机制以及各激素在棉花蕾铃脱落以及其他植物(生殖)器官脱落过程中的响应和调控机制等。发现目前以棉花蕾铃脱落为对象的研究非常匮乏,且多集中于少数激素对棉花生殖生长影响的有限研究,缺乏对导致蕾铃脱落的深层次机制的探究和解析。因此,未来研究方向应着重于探究棉花蕾铃脱落的遗传基础、发掘新的抗脱落基因资源和培育抗脱落棉花品种,同时加强在以棉花为模型植物下,蕾铃脱落与植物激素调节的关系研究,为提高棉花产量提供理论依据和技术支持。

关键词：棉花植物激素蕾铃脱落研究现状研究方向

栓塞微球应用于肝动脉化疗栓塞治疗乏血供肝癌的临床观察

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中国肿瘤临床与康复 2017年第5期24卷 533-536页

作者：张英邓俊周颜陆忠华姚悦萍吴晓霞陈卫江苏省无锡市第五人民医院肿瘤介入科无锡214007

目的探讨栓塞微球应用于肝动脉化疗栓塞(TACE)治疗乏血供肝癌的临床疗效。方法选取2011年6月至2013年12月间无锡市第五人民医院收治的60例原发性肝癌患者,采用随机数表法分为研究组与对照组,每组30例。研究组患者采用栓塞微球为栓塞剂,... 详细信息

目的探讨栓塞微球应用于肝动脉化疗栓塞(TACE)治疗乏血供肝癌的临床疗效。方法选取2011年6月至2013年12月间无锡市第五人民医院收治的60例原发性肝癌患者,采用随机数表法分为研究组与对照组,每组30例。研究组患者采用栓塞微球为栓塞剂,对照组以碘化油加明胶海绵为栓塞剂,患者均至少经过两次肝动脉化疗栓塞术后,比较两组患者肿瘤病灶近期变化、不良反应及生存时间。结果术后研究组患者肝功能损害指标谷丙转氨酶(ALT)值高于对照组患者,差异有统计学意义(P<0.05)。研究组患者和对照组患者的总有效率分别为40.0%和20.0%,疾病控制率分别为93.3%和70.0%,差异有统计学意义(P<0.05)。研究组患者18个月生存率优于对照组患者,研究组患者和对照组患者中位生存时间分别为11个月和8个月,差异均有统计学意义(均P<0.05)。结论以栓塞微球为栓塞剂的肝动脉化疗栓塞对乏血供肝癌具有一定的疗效,值得临床进一步研究。

关键词：原发性肝肿瘤乏血供栓塞微球

Promotion of Cooperation in a Spatial Public Goods Game with Long Range Learning and Mobility

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Chinese Physics Letters 2012年第11期29卷 231-235页

作者： XIAO yao hua Da-Yin Department of Physics Ningbo UniversityNingbo 315211

We studied the effect of population density in a spatial public goods *** found that the effect on the evolution of cooperation is very complex when the strategy learning and mobility of players in a long range are considered in a two-dimensional *** the learning range is larger than the mobility range,the system is driven to enter into a cooperation state for a low population density,because a small local group is beneficial to sustain a high level of *** population density increases to a moderate range,the mobility of players from a domain invaded by defectors supports the evolution stability of *** the mobility range is larger than the learning range,a formation of compact domains of cooperators promotes cooperation as the population density becomes high.

关键词： cooperation operators learning