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Global Convergence of a Modified PRP Conjugate Gradient Method

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Journal of Mathematical Research and Exposition 2010年第1期30卷 141-148页

作者： Hai Dong HUANG Yan Jun li zeng xin WEI College of Mathematics and Information Science Guangxi University Guangxi 530004 P. R. China

In this paper, a modified formula for βk^PRP is proposed for the conjugate gradient method of solving unconstrained optimization problems. The value of βk^PRP keeps nonnegative independent of the line search. Under mild conditions, the global convergence of modified PRP method with the strong Wolfe-Powell line search is established. Preliminary numerical results show that the modified method is efficient.

关键词： unconstrained optimization conjugate gradient method global convergence.

P-μc-Si_(1-x)Ge_x:H thin film by VHF-PECVD

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Optoelectronics Letters 2008年第2期4卷 130-132页

作者： SHANG Ze-ren ZHANG Jian-jun ZHANG li-ping HU zeng-xin XUE Jun-ming ZHAO Ying GENG xin-hua Key Laboratory of Photo-Electronics Thin Film Devices and Technique of Tianjin Key Laboratory of OPtoelectronic Information Science and Technology of Education Ministry Institute of Photo-Electronics Thin Film Devices and Technology Nankai University Tianjin 300071 China

In this paper, a series of boron doped microcrystalline hydrogenated silicon-germanium （p-μc-Si1-xGex：H） was deposited by very high frequency plasma-enhanced chemical vapor deposition （VHF-PECVD） from SiH4 and GeF4 mixtures. The effect of GeF4 concentration on films＇ composition, structure and electrical properties was studied. The results show that with the increase of GeF4 concentration, the Ge fraction x increases. The dark conductivity and crystalline volume fraction increase first, and then decrease. When the GC is 4%, p-μc-Si1-xGex：H material with high conductivity, low activation energy （σ= 1.68 S/cm, E8=0.047 eV）, high crystalline volume fraction （60%） and with an average transmission coefficient over the long wave region reaching 0.9 at the thickness of 72 nm was achieved. The experimental results were discussed in detail.

关键词： VHF-PECVD 薄膜化学纤维光半导体

Influencing factors of early post-traumatic stress disorder in young and middle-aged individuals with open globe injuries in west China:a cross-sectional study

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International Journal of Ophthalmology(English edition) 2025年第1期18卷 146-153页

作者： Yi-Man li xin Zhang Ji-Hong zeng Hong-Mei Luo Department of Ophthalmology West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina

AIM:To evaluate the prevalence of early post-traumatic stress disorder(PTSD)among young and middle-aged patients who have suffered open globe injuries,and to identify the psychosocial factors influencing PTSD in these ***:A total of 280 patients who underwent ocular trauma surgery between January 2023 and January 2024 were selected through convenience *** were collected using a custom-designed demographic questionnaire,the Connor-Davidson Resilience Scale(CDRISC),the Cognitive Emotion Regulation Questionnaire(C-ERRI),and the PTSD Checklist-Civilian Version(PCL-C).Univariate analysis and stepwise multiple linear regression analysis were performed to determine the factors affecting PTSD in these ***:The average PTSD score for the patients was 33.22±*** scores for individual PTSD dimensions,ranked from highest to lowest,were recurrent traumatic experiences,heightened arousal,avoidance reactions,and social *** PTSD symptoms were observed in 85 patients(30.36%).Univariate analysis indicated that gender,postoperative vision,marital status,psychological resilience,and rumination were significant factors affecting PTSD symptoms(χ^(2)/t=6.53,17.88,8.83,2.17,and 14.1,respectively;all Plience and PTSD symptoms(r=-0.14,Plinear regression analysis identified postoperative vision(notably eye removal),rumination levels,and psychological resilience(optimism)as major factors influencing PTSD in these patients(R^(2)=0.57,Plience(optimism).Conversely,patients with good postoperative vision recovery,low rumination l

关键词： young and middle-aged open globe injuries post-traumatic stress disorder rumination psychological resilience

Regulating crystallization and retarding oxidation in Sn-Pb perovskite via 1D cation engineering for high performance all-perovskite tandem solar cells

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Journal of Energy Chemistry 2025年第1期100卷 646-652页

作者： Ranran liu xin Zheng Zaiwei Wang Miaomiao zeng Chunxiang Lan Shaomin Yang Shangzhi li Awen Wang Min li Jing Guo Xuefei Weng Yaoguang Rong Xiong li Michael Grätzel Center for Mesoscopic Solar Cells Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan 430074HubeiChina Institute of Technology for Carbon Neutrality Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongChina School of Chemistry Chemical Engineering and Life SciencesState Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of Technology430070HubeiChina Suzhou Institute of Nano-Tech and Nano-Bionics(SINANO) Chinese Academy of SciencesSuzhou 215123JiangsuChina School of Physics and Optoelectronic Engineering Hainan UniversityHaikou 570228HainanChina

All-perovskite tandem solar cells have the potential to surpass the theoretical efficiency limit of single junction solar cells by reducing thermalization ***,the challenges encompass the oxidation of Sn^(2+)to Sn^(4+)and uncontrolled crystallization kinetics in Sn-Pb perovskites,leading to nonradiative recombination and compositional heterogeneity to decrease photovoltaic efficiency and operational ***,we introduced an ionic liquid additive,1-ethyl-3-methylimidazolium iodide (EMIMI) into Sn-Pb perovskite precursor to form low-dimensional Sn-rich/pure-Sn perovskites at grain boundaries,which mitigates oxidation of Sn^(2+)to Sn^(4+)and regulates the film-forming dynamics of Sn/Pb-based perovskite *** optimized single-junction Sn-Pb perovskite devices incorporating EMIMI achieved a high efficiency of 22.87%.Furthermore,combined with wide-bandgap perovskite sub-cells in tandem device,we demonstrate 2-terminal all-perovskite tandem solar cells with a power conversion efficiency of 28.34%,achieving improved operational stability.

关键词： All-perovskite tandem solar cells Sn-Pb perovskite 1D Regulated crystallization Antioxidation

Holographic images of a charged black hole in Lorentz symmetry breaking massive gravity

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 59-72页

作者： Xiao-Xiong zeng li-Fang li Pan li Bo liang Peng Xu College of Physics and Electronic Engineering Chongqing Normal UniversityChongqing 401331China Department of Mechanics Chongqing Jiaotong UniversityChongqing 400074.China Center for Gravitational Wave Experiment National Microgravity LaboratoryInstitute of MechanicsChinese Academy of SciencesBeijing 100190China Lanzhou Center of Theoretical Physics Lanzhou UniversityLanzhou 730000China

Using the AdS/CFT correspondence,this paper investigates the holographic images of a charged black hole within the context of Lorentz symmetry breaking massive *** photon rings,luminosity-deformed rings,or light points from various observational perspectives are *** also study the influences of both the chemical potential and temperature on the Einstein *** the previous work,which primarily examines the effect of chemical potential on ring radius at high temperatures and find no change in the radius with varying chemical potential,we also investigate the effect of chemical potential on the ring radius at low temperature besides at high *** findings indicate that at low temperatures,the photon ring radius decreases with increasing of chemical potential,while at high temperatures,the results are consistent with previous ***,we explore the impact of the model parameterλon the Einstein ring radius and find the the ring radius increases as the model parameterλ*** interestingly,for the large chemical potential,u=1,the temperature dependence of the photon ring radius is reversed forλ=2 andλ=***,for a small chemical potential u=0.1,the temperature dependence of the Einstein ring stays the same asλ=2 andλ=4.

关键词： AdS/CFT correspondence holographic images massive gravity black holes

Trifluoromethylative homo-coupling of carbonyl compounds

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Chinese Chemical Letters 2025年第1期36卷 283-287页

作者： xinlong Han Huiying zeng Chao-Jun li The State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000China Department of Chemistry FQRNT Centre for Green Chemistry and CatalysisMcGill UniversityMontrealQuebecH3A 0B8Canada

Carbonyl compounds are abundant in nature and represent a substantial portion of biomass *** significant recent progress in homo-coupling of carbonyl compounds,achieving their deoxyfunctionalization homo-coupling remains a highly intricate ***,we report an entirely novel reaction paradigm:the trifluoromethylative homo-coupling of carbonyl compounds via hydrazones,which enables the formation of three C(sp^(3))-C(sp^(3))bonds in a single *** method provides a new pathway for synthesizing trifluoromethylative coupling product which has unique applications in both fields of medical and material *** investigations have unveiled that the formation of a trifluoromethyl-substituted benzyl radical plays a pivotal role as a key intermediate in this reaction.

关键词： Carbonyl compounds Trifluoromethylation Homo-coupling C(sp^(3))-C(sp^(3))bond formation

A Modified Conjugate Gradient Method with Global Convergence Property

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Journal of Mathematical Research and Exposition 2009年第1期29卷 65-75页

作者： HONG ling MO li liu WEI zeng xin College of Mathematics & Information Science Guangxi University Guangxi 530004 China

A new conjugate gradient method is proposed in this paper. For any （inexact） line search, our scheme satifies the sufficient descent property. The method is proved to be globally convergent if the restricted Wolfe-P... 详细信息

关键词： unconstrained optimization conjugate gradient method Wolfe-Powell line search global convergence.

基于ELES模型的湖南城乡居民消费结构差异研究

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消费经济 2006年第3期22卷 84-86页

作者：李增欣中南大学商学院长沙410083

ELES模型是当前国内外比较流行的研究消费结构的计量经济模型,它能较好地将经验研究与理论分析结合起来。本文运用ELES模型,对湖南城乡居民消费结构的时间序列数据进行了较为全面、深入的计量检验,分析了城乡居民消费结构差异的情况,并... 详细信息

ELES模型是当前国内外比较流行的研究消费结构的计量经济模型,它能较好地将经验研究与理论分析结合起来。本文运用ELES模型,对湖南城乡居民消费结构的时间序列数据进行了较为全面、深入的计量检验,分析了城乡居民消费结构差异的情况,并提出了相应的政策建议。

关键词：企业消费利益自然资源和生态环境的价值对策

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长江水患灾害成因及其防治途径

西北大学学报（自然科学版） 1999年第2期29卷 176-179页

作者：李增新水利部水电规划设计总院

分析了长江水患灾害发生的主要成因即降水量大而集中、森林破坏造成水土流失加剧、水利工程设防标准较低等及其有关区域因素，在此基础上，提出了恢复生态平衡，建立标本兼治的防洪体系的基本思路即改变传统的被动“治水”方式，积极重... 详细信息

分析了长江水患灾害发生的主要成因即降水量大而集中、森林破坏造成水土流失加剧、水利工程设防标准较低等及其有关区域因素，在此基础上，提出了恢复生态平衡，建立标本兼治的防洪体系的基本思路即改变传统的被动“治水”方式，积极重视“疏导”洪水，统筹规划、加大投入，开展全流域综合治理以及封山育林、限制采伐、退耕还林、涵养水土资源；积极适度退田还湖，加大调蓄干流洪水；加固加高长江干流干堤。

关键词：长江洪水成因治理防治水灾