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Energy band modulation of N-doped rutile/anatase TiO_(2) photoanode promoting charge separation toward prominent photoelectrochemical performance

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Rare Metals 2024年第8期43卷 3784-3797页

作者： Juan Gao Shi-Xuan Wang Jia-Le Deng Ping-Ping Wei fu-zhang chen Ling-cheng Zheng Yue-Qin Wang Yang Li Yin Liu Gang He School of Mechanics and Photoelectric Physics Anhui University of Science and TechnologyHuainan 232001China School of Materials Science and Engineering Anhui UniversityHefei230039China Tianneng Battery(Wuhu)Co. Ltd.Wuhu 241000China School of Materials Science and Engineering Anhui University of Science and TechnologyHuainan 232001China

To solve the problem of high photogenerated carrier recombination rate and low photoelectric conversion efficiency of TiO_(2)-based materials,a simple N-doped anatase/rutile TiO_(2) heterophase nanorod film was designed by a low-temperature hydrothermal method in this *** enhanced separation and transport of photogenerated charges were facilitated by the smaller contact barrier and appropriate band matching between anatase TiO_(2)nanoparticles and rutile TiO_(2) *** introduction of N doping in anatase TiO_(2) resulted in an upward shift of the valence band and a narrowing of the band gap,consequently enhancing the efficiency of visible light *** combination of the heterophase junction and N-doping exhibited a synergistic effect,effectively suppressing the recombination of photogenerated charges and enhancing the photoelectric conversion efficiency of the *** AM 1.5G irradiation,the photocurrent density(J)of the A-TO(N)@R-TONR photoanode reached2.19 mA·cm^(-2)(V_(RHE,1.23 eV)).Additionally,the incident photon-electron conversion efficiency(IPCE)and the charge injection efficiency(η)reached 81.4%and 51.6%at320 ***,the J,IPCE,andηvalues of the A-TO(N)@R-TONR photoanode were 2.96,2.1 and 3.2times those of pure R-TONR photoanode,*** work presents a rational strategy for designing efficient TiO_(2)-based photoanodes.

关键词： TiO_(2) Heterophase junction Photoanode

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基于课堂观察的小学语文教师教学行为改进策略——以××小学三年级语文课堂为案例

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当代教研论丛 2024年第7期10卷 99-102页

作者：张福臣安徽省颍上县教师进修学校安徽阜阳236200

双减背景下,新课程标准对小学教学提出了更高的要求,而教师教学行为直接影响实际教学改革效果。文章以课堂观察为研究方法,根据小学语文教师教学特点,设计小学教师教学行为课堂观察表,分析小学语文教师教学行为问题,提出具有针对性的小... 详细信息

双减背景下,新课程标准对小学教学提出了更高的要求,而教师教学行为直接影响实际教学改革效果。文章以课堂观察为研究方法,根据小学语文教师教学特点,设计小学教师教学行为课堂观察表,分析小学语文教师教学行为问题,提出具有针对性的小学语文教师教学行为改进策略,为小学教师教学行为改进提供有益参考。

关键词：课堂观察小学教师教学行为改进

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一个广义Lorenz系统平衡点的局部稳定性与全局吸引性

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四川大学学报（自然科学版） 2024年第2期61卷 36-39页

作者：祝崇涵张付臣穆春来重庆工商大学数学与统计学院/统计智能计算与监测重庆市重点实验室重庆400067 重庆大学数学与统计学院重庆401331

本文研究了一个广义Lorenz系统的平衡点的稳定性(全局指数稳定、全局渐近稳定)及不稳定的判据,获得了系统的全局吸引性,并推广了已有的一些混沌演化研究方法.

关键词：广义Lorenz系统稳定性吸引域

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New chaotical image encryption algorithm based on Fisher–Yatess scrambling and DNA coding

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Chinese Physics B 2019年第4期28卷 121-130页

作者： Xing-Yuan Wang Jun-Jian zhang fu-chen zhang Guang-Hui Cao School of Information Science and Technology Dalian Maritime University Faculty of Electronic Information and Electrical Engineering Dalian University of Technology College of Mathematics and Statistics Chongqing Technology and Business University School of Electronics & Information Engineering Liaoning University of Technology

Based on the Fisher–Yatess scrambling and DNA coding technology, a chaotical image encryption method is proposed. First, the SHA-3 algorithm is used to calculate the hash value of the initial password, which is used as the initial value of the chaotic system. Second, the chaotic sequence and Fisher–Yatess scrambling are used to scramble the plaintext,and a sorting scrambling algorithm is used for secondary scrambling. Then, the chaotic sequence and DNA coding rules are used to change the plaintext pixel values, which makes the ciphertext more random and resistant to attacks, and thus ensures that the encrypted ciphertext is more secure. Finally, we add plaintext statistics for pixel-level diffusion to ensure plaintext sensitivity. The experimental results and security analysis show that the new algorithm has a good encryption effect and speed, and can also resist common attacks.

关键词： Fisher–Yatess scrambling chaotic sequence DNA coding image encryption

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Keyhole approach surgery for petroclival meningioma

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Chinese Medical Journal 2006年第16期119卷 1339-1342页

作者： ZHU Wei MAO Ying ZHOU Liang-fu zhang Rong chen Liang Department of Neurosurgery Shanghai Neurosurgical Center Huashan Hospital of Fudan University Shanghai 200040 China

Background In China, the feasibility of keyhole approach in surgical treatment of petroclival meningioma has not been well evaluated. This report summarized our experience in 25 patients with petroclival meningioma who had been treated with keyhole approach surgery. Methods From July 2000 to July 2005, 25 patients with petroclival meningioma were subjected to resection via subtemporal, retrosigmoid or combined keyhole approaches. The extent of tumor resection was evaluated by MRI 3 months after surgery, and postoperative complications were investigated. Results The maximum diameter of tumors ranged from 2 to 7 cm （mean, 4.5 cm）. Gross total resection （GTR） was achieved in 14 patients, giving a GTR rate of 56%. Subtotal resection （STR） was carried out in 8 patients and partial resection in 3. Thirteen patients kept normal neurological status, whereas others suffered from cranial nerve deficits （Ⅶ, Ⅶ, Ⅲ and lower CN）. One patient died in the postoperative period. Conclusions Keyhole approach surgery, especially the combined keyhole approach is suitable for the treatment of petroclival meningioma. It provides easy and quick access to the supra- and infratentorial juxta-clival region without drilling of the petrous bone. Complications related to the approach can be minimized.

关键词： keyhole surgery petroclival meningioma subtemporal approach retrosigmoid approach

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Initial precursor reaction mechanism of CVD-HfC coating based on density functional theory

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Chinese Journal of Aeronautics 2024年第7期37卷 511-521页

作者： Yunzhou LIN Yulei zhang Yanqin fu Jian zhang Jing’an KONG Ruicong chen State Key Laboratory of Solidification Processing Carbon/Carbon Composites Research CenterNorthwestern Polytechnical UniversityXi’an 710072China Henan Key Laboratory of High Performance Carbon Fiber Reinforced Composites Carbon Matrix Composites Research InstituteHenan Academy of SciencesZhengzhou 450046China

Recently,the preparation of ultra-high temperature HfC ceramic coating has gained significant attention,particularly through the application of the HfCl_(4)-CH_(4)-H_(2)-Ar system via Chemical Vapor Deposition(CVD),which has been found widely applied to C/C ***,an analysis of the reactions that occur in the initial stage of the CVD-HfC coating process is presented using Density functional Theory(DFT)and Transition State Theory(TST)at the B3LYP/Lanl2DZ *** results reveal that HfCl4 can only cleave to produce hypochlorite,which will further react with methyl to synthesize intermediates to form *** to the analysis of the energy barrier and reaction constant,HfCl preferentially reacts with methyl groups to form complex adsorptive intermediates at 1573 *** a C—Hf bond production energy of 212.8 kcal/mol(1 kcal=4.18 kJ),the reaction rate constant of HfCl+CH is calculated to be 2.15×10^(-18) cm^(3)/s at 1573 ***,both the simulation and experimental results exhibit that the upward trend of reaction rate constants with temperature is also consistent with the deposition rate,indicating that the growth curve of the reaction rate constants tends to flatten *** proposed reaction model of the precursor’s decomposition and reconstruction during deposition process has significant implication for the process guidance.

关键词： Carbon composite HfC coating Chemical vapor deposition Density functional theory Precursor reaction mechanism

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Novel Hf_(x)Ta_(1−x)C solid solution nanowire toughened HfC coating:An effective strategy for synchronous enhanced mechanical and anti-ablation performance

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Journal of Advanced Ceramics 2024年第5期13卷 590-601页

作者： Hui chen Yulei zhang Yanqin fu Wenhan Gai Junhao Zhao Haohui zhang Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials Northwestern Polytechnical UniversityXi’an 710072China Henan Key Laboratory of High Performance Carbon Fiber Reinforced Composites Institute of Carbon Matrix CompositesHenan Academy of SciencesZhengzhou 450046China

Ultra-high-temperature ceramic nanowires have shown increasing potential for use as thermal structural ***,novel single-crystal Hf_(0.5)Ta_(0.5)C solid solution nanowires were synthesized and incorporated with a HfC coating to construct a robust structure with Hf_(0.5)Ta_(0.5)C solid solution nanowires uniformly distributed and interconnected within the *** novel Hf_(0.5)Ta_(0.5)C solid solution nanowires could effectively hinder crack propagation through crack tip pinning and crack *** mechanism substantially enhanced the elastic modulus and fracture toughness of the HfC coating by 53.29%and 59.67%,*** toughened HfC coating displayed superior fracture toughness and good interfacial binding strength with the substrate to resist severe oxidation and ***,the high thermal conductivity of the toughened HfC coating promoted heat ***,in comparison to the pure HfC coating,the toughened HfC coating displayed smaller mass and linear ablation rates of−0.35 mg·s^(−1)and−0.46μm·s^(−1),which decreased by 39.66%and 36.98%,*** work not only simultaneously enhances the mechanical properties and ablation resistance of HfC-coated carbon/carbon(C/C)composites but also provides novel prospects for advanced ultrahigh-temperature ceramic nanowires under extreme conditions.

关键词： Hf_(x)Ta_(1−x)C solid solution nanowires HfC coating carbon/carbon(C/C)composites mechanical performance ablationresistance

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Reactive molecular dynamics insight into the thermal decomposition mechanism of 2,6-Bis(picrylamino)-3,5-dinitropyridine

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Defence Technology（防务技术） 2024年第3期33卷 134-146页

作者： Jianbo fu Hui Ren Xinzhou Wu Yongjin chen Mi zhang Yazhi cheng State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

2,6-bis(picrylamino)-3,5-dinitropyridine(PYX)has excellent thermostability,which makes its thermal decomposition mechanism receive much *** this paper,the mechanism of PYX thermal decomposition was investigated thoroughly by the ReaxFF-lg force field combined with DFT-B3LYP(6-311++G)*** detailed decomposition mechanism,small-molecule product evolution,and cluster evolution of PYX were mainly *** the initial stage of decomposition,the intramolecular hydrogen transfer reaction and the formation of dimerized clusters are earlier than the denitration *** the progress of the reaction,one side of the bitter amino group is removed from the pyridine ring,and then the pyridine ring is *** final products produced in the thermal decomposition process are CO_(2),H_(2)O,N_(2),and H_(2).Among them,H_(2)O has the earliest generation time,and the reaction rate constant(k_(3))is the *** clusters are formed during the decomposition of PYX,and the formation,aggregation,and decomposition of these clusters are strongly affected by *** low temperatures(2500 K-2750 K),many clusters are *** high temperatures(2750 K-3250 K),the clusters aggregate to form larger *** 3500 K,the large clusters decompose and become *** the late stage of the reaction,H and N in the clusters escaped almost entirely,but more O was trapped in the clusters,which affected the auto-oxidation process of ***'s initial decomposition activation energy(E_(a))was calculated to be 126.58 kJ/*** work contributes to a theoretical understanding of PYX's entire thermal decomposition process.

关键词： PYX Thermal decomposition ReaxFF-lg MD simulations Excellent thermostable explosives

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Pore Formation Mechanism in W-C Hard Coatings Using Directed Energy Deposition on Tungsten Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 89-101页

作者： Xinrui zhang Weijie fu chen Wang Zhenglong Lei Haoran Sun Xudong Li State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin150001China

Porosity is a common phenomenon and can significantly hinder the quality of the ***,the pore formation mechanism and the characteristics of the single tracks of the W-C coating using directed energy deposition(DED)are systematically *** forming quality of the tracks,the distribution of the pores,and the elemental distribution near the pores are analyzed by the observations of the cross-sections of the *** temperature field of the melt pool is discussed comprehensively to reveal the pore formation *** results confirm that Ni and Co evaporated during the DED process due to the high temperature of the melt *** were continuously produced adjacent to the fusion line when the melt pool was about to solidify since the temperature at the solidification front was higher than the boiling point of *** vaporization area at the fusion line was proposed,where Ni could also evaporate at the time the melt pool started to *** relationship between the solidification rate,the size of the vaporization area and the DED parameters(laser power and scanning speed)was established to discuss the causes of severe pores above the fusion *** work contains a practical guide to reduce or eliminate the porosity in the coating preparation process on the surface of the tungsten alloy.

关键词： Directed energy deposition(DED)process Tungsten alloy W-C coating Pores Binder phase

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A Li_(3)P nanoparticle dispersion strengthened ultrathin Li metal electrode for high energy density rechargeable batteries

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Nano Research 2024年第5期17卷 4031-4038页

作者： Lin fu Xiancheng Wang Bao zhang Zihe chen Yuanjian Li Yongming Sun Provincial Guizhou Key Laboratory of Green Chemical and Clean Energy Technology School of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang 550025China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore Institute of Materials Research and Engineering Agency for Science Technology and Research(A*STAR)Singapore 138634Singapore

Achievement of lithium(Li)metal anode with thin thickness(e.g.,≤30µm)is highly desirable for rechargeable high energy density ***,the fabrication and application of such thin Li metal foil electrode remain challenging due to the poor mechanical processibility and inferior electrochemical performance of metallic ***,mechanico-chemical synthesis of robust ultrathin Li/Li_(3)P(LLP)composite foils(~15µm)is demonstrated by employing repeated mechanical rolling/stacking operations using red P and metallic Li as raw *** in-situ formed Li+-conductive Li_(3)P nanoparticles in metallic Li matrix and their tight bonding strengthen the mechanical durability and enable the successful fabrication of free-standing ultrathin Li metal composite ***,it also reduces the electrochemical Li nucleation barrier and homogenizes Li plating/stripping *** matching to high-voltage LiCoO_(2),the full cell with a low negative/positive(N/P)capacity ratio of~1.5 offers a high energy density of~522 W·h·kg^(-1) at 0.5 C based on the mass of cathode and *** into account its facile manufacturing,potentially low cost,and good electrochemical performance,we believe that such an ultrathin composite Li metal foil design with nanoparticle-dispersion-strengthened mechanism may boost the development of high energy density Li metal batteries.

关键词： lithium metal anode high energy density battery mechanico-chemical synthesis ultrathin Li/Li_(3)P composite foil low negative/positive capacity ratio

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