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Journal of Forestry Research 2024年第4期35卷 189-201页

作者： yuxia Wu xuedan yu Wei Tang Wenhua Yang Qidi Fu Yongqi Zheng Chuanhong Zhang State Key Laboratory of Tree Genetics and Breeding Research Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China Beijing Waiyan Online Digital Technology Co. LtdBeijing 100081People’s Republic of China Huabanlv Nature Enlightenment Education Technology Co. LtdBeijing 100010People’s Republic of China

In overlapping distribution areas of Sorbus pohuashanensis and *** in North China(Mount Tuoliang,Mount Xiling and Mount Baihua),Sorbus indi-viduals were found with pink fruit,which have never been recorded for the flora of *** morphological characters combined with four chloroplast DNA markers and internal transcribed spacer(ITS)were used to analyze the origin of the Sorbus individuals with pink fruits and their relationship to *** and ***,SDA and one-way(taxon)ANOVA of morphological characters provided convincing evidence of the hybrid ori-gin of Sorbus individuals with pink fruits based on a novel morphological character and many intermediate *** analysis based on four cpDNA markers showed that either *** or *** were maternal parents of Sorbus individuals with pink ***-ence of the position of Sorbus individuals with pink fruits between cpDNA and ITS in cluster trees supported by DNA sequence comparative analysis,implying former hybridiza-tion events between *** and ***-tiple hybridization events between *** and *** might have contributed to the generation of Sorbus individuals with pink *** study has provided insights into hybridization between species of the same genus in sympatric areas,which is of great significance for the study of interspecific hybridization.

关键词： Hybridization ITS Chloroplast DNA Morphological characters Sorbus

An effective'salt in dimethyl sulfoxide/water'electrolyte enables high-voltage supercapacitor operated at-50℃

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Journal of Energy Chemistry 2024年第6期93卷 361-367,I0009页

作者： Yingbin Liu Chang yu xuedan Song Siyi Hou Shuqin Lan Jinhe yu yuanyang Xie Jieshan Qiu State Key Lab of Fine Chemicals Frontier Science Center for Smart MaterialsSchool of Chemical EngineeringLiaoning Key Lab for Energy Materials and Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina School of Chemistry Frontier Science Center for Smart MaterialsLiaoning Key Lab for Energy Materials and Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina College of Chemical Engineering State Key Laboratory of Chemical Resource EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Compared with organic electrolytes,aqueous electrolytes exhibit significantly higher ionic conductivity and possess inherent safety features,showcasing unique advantages in ***,challenges remain for low-salt aqueous electrolytes operating at high voltage and low ***,we report a low-salt(0.87 m,m means mol kg^(-1))'salt in dimethyl sulfoxide/water'hybrid electrolyte with non-flammability via hybridizing aqueous electrolyte with an organic co-solvent of dimethyl sulfoxide(hydrogen bond acceptor).As a result,the 0.87 m hybrid electrolyte exhibits enhanced electrochemical stability,a freezing temperature below-50℃,and an outstanding ionic conductivity of 0.52mS cm~(-1)at-50℃.Dimethyl sulfoxide can anchor water molecules through intermolecular hydrogen bond interaction,effectively reinforcing the stability of water in the hybrid ***,the interaction between dimethyl sulfoxide and water molecules diminishes the involvement of water in the generation of ordered ice crystals,finally facilitating the low-temperature performance of the hybrid *** paired with the 0.87 m'salt in dimethyl sulfoxide/water'hybrid electrolyte,the symmetric supercapacitor presents a 2.0 V high operating voltage at 25℃,and can operate stably at-50℃.Importantly,the suppressed electrochemical reaction of water at-50℃further leads to the symmetric supercapacitor operated at a higher voltage of 2.6 *** modification strategy opens an effective avenue to develop low-salt electrolytes for high-voltage and low-temperature aqueous supercapacitors.

关键词： Dimethyl sulfoxide Co-solvent High voltage Low temperature Supercapacitors

Intrinsic pentagon defect engineering in multiple spatial-scale carbon frameworks for efficient triiodide reduction

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Journal of Energy Chemistry 2024年第8期95卷 20-28,I0002页

作者： Siyi Hou xuedan Song Chang yu Jiangwei Chang Yiwang Ding Yingbin Liu Xiubo Zhang Weizhe Liu Jieshan Qiu State Key Lab of Fine Chemicals Liaoning Key Lab for Energy Materials and Chemical EngineeringFrontier Science Center for Smart MaterialsSchool of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina Liaoning Key Lab for Energy Materials and Chemical Engineering Frontier Science Center for Smart MaterialsSchool of ChemistryDalian University of TechnologyDalian 116024LiaoningChina State Key Laboratory of Chemical Resource Engineering College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Intrinsic topological defect engineering has been proven as a promising strategy to elevate the electrocatalytic activity of carbon ***,the controllable construction of high-density and specific topological defects in carbon frameworks to reveal the relationship between reactivity and defect structure remains a challenging ***,the intrinsic pentagon carbon sites that can favor electron overflow and enhance their binding affinity towards the intermediates of catalytic reaction are firstly presented by the work function and the p-band center *** experimentally verify this,the cage-opening reaction of fullerene is proposed and utilized for synthesizing carbon quantum dots with specific pentagon configuration(CQDs-P),subsequently utilizing CQDs-P to modulate the micro-scale defect density of three-dimensional reduced graphene oxide(rGO)viaπ-π*** multiple spatial-scale rGO-conjugated CQDs-P structure simultaneously possesses abundant pentagon and edge defects as catalytic active sites and long-range-orderedπelectron delocalization system as conductive *** defects-rich CQDs-P/rGO-4 all-carbon-based catalyst exhibits superb catalytic activity for triiodide reduction reaction with a high photoelectric conversion efficiency of 8.40%,superior to the Pt reference(7.97%).Theoretical calculations suggest that pentagon defects in the carbon frameworks can promote charge transfer and modulate the adsorption/dissociation behavior of the reaction intermediates,thus enhancing the electrocatalytic activity of the *** work confirms the role of intrinsic pentagon defects in catalytic reactions and provides a new insight into the synthesis of defects-rich carbon catalysts.

关键词： Defect engineering Pentagon carbon Carbon quantum dots Electrocatalytic activity Triiodide reduction

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护士工作压力与职业耗竭感的相关性研究

中国护理管理 2014年第4期14卷 401-402页

作者：余雪丹武汉市汉口医院二七院区综合内科 430012

目的:探讨武汉市三级医院护士工作压力与职业耗竭感的关系。方法:应用工作压力问卷、职业耗竭感问卷对武汉市3所三级医院的176名护士进行问卷调查,分析工作压力与职业耗竭感之间的关系。结果 :护士面临较大的工作压力,其中来自工作环境... 详细信息

目的:探讨武汉市三级医院护士工作压力与职业耗竭感的关系。方法:应用工作压力问卷、职业耗竭感问卷对武汉市3所三级医院的176名护士进行问卷调查,分析工作压力与职业耗竭感之间的关系。结果 :护士面临较大的工作压力,其中来自工作环境与性质的压力最大(19.39±7.95);护士职业耗竭感从整体状况来看并不十分严重,但情绪衰竭体验比较严重;护士职业耗竭感与工作压力呈正相关(r=0.219,P<0.01),随工作压力的增加,职业耗竭感的程度变得更为严重。结论:护士工作压力对职业耗竭感有重要影响,建议护理管理者采取有效的管理方法,减少护士的工作压力,从而减轻其职业耗竭感。

关键词：护士工作压力职业耗竭感相关性

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社区肿瘤病人的家庭护理

家庭护士（下旬） 2007年第2期5卷 84-86页

作者：余雪丹湖北省武汉市汉口铁路医院 430030

从肿瘤病人的环境要求、基础护理、特殊护理、心理干预、康复指导、临终关怀方面叙述肿瘤病人的家庭护理，提出有效的家庭护理在肿瘤病人的康复中起着重要的作用．

关键词：社区肿瘤家庭护理

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护士工作压力与职业枯竭的关系研究

护理研究 2014年第20期28卷 2484-2485页

作者：余雪丹湖北省武汉市汉口医院

[目的]了解护士工作压力与职业枯竭的现状,探讨工作压力与护士职业枯竭的关系。[方法]采用职业枯竭问卷、工作压力源问卷对武汉市176名护士进行问卷调查。[结果]护士职业枯竭与工作压力呈正相关,职业枯竭的程度随工作压力的增加而加重。... 详细信息

[目的]了解护士工作压力与职业枯竭的现状,探讨工作压力与护士职业枯竭的关系。[方法]采用职业枯竭问卷、工作压力源问卷对武汉市176名护士进行问卷调查。[结果]护士职业枯竭与工作压力呈正相关,职业枯竭的程度随工作压力的增加而加重。[结论]工作压力对护士职业枯竭有重要影响,护理管理者应合理调配人力资源,以减轻护士工作压力。

关键词：护士工作压力职业枯竭

理论研究Cu@C_(2)N催化剂表面上水分子对电催化CO_(2)还原反应机理的影响

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物理化学学报 2024年第1期40卷 24-25页

作者：徐涵煜宋雪旦张青于畅邱介山大连理工大学化工学院辽宁省能源材料化工重点实验室精细化工国家重点实验室辽宁大连116024 北京化工大学化学工程学院有机无机复合材料国家重点实验室化工资源有效利用国家重点实验室北京100029

电催化CO_(2)还原反应(CO_(2)RR)的反应途径涉及多个质子-电子对转移,在水溶剂条件下,质子的来源是水分子,考虑水分子对质子-电子对的转移机制十分必要。本研究提出水辅助氢穿梭模型,与常用的以氢原子作为氢源的直接加氢模型对比,研究... 详细信息

电催化CO_(2)还原反应(CO_(2)RR)的反应途径涉及多个质子-电子对转移,在水溶剂条件下,质子的来源是水分子,考虑水分子对质子-电子对的转移机制十分必要。本研究提出水辅助氢穿梭模型,与常用的以氢原子作为氢源的直接加氢模型对比,研究水分子在CO_(2)RR中对质子-电子对转移的影响。采用密度泛函理论,系统地研究了铜原子嵌入C_(2)N单层催化剂(Cu@C_(2)N)和石墨烯作为衬底的Cu@C_(2)N/石墨烯复合催化剂(Cu@C_(2)N/G)表面上不同加氢模型的CO_(2)RR反应机理。在水辅助氢穿梭模型中,氢原子与水分子结合形成水合质子,水合质子将自身的氢原子转移到催化剂表面的反应物上形成反应中间体,增强了中间体与催化剂之间的相互作用。此外,在Cu@C_(2)N/G催化剂中,石墨烯将电子转移到表面的Cu@C_(2)N上,提高了催化剂的CO_(2)RR催化活性。进一步,计算了Cu@C_(2)N和Cu@C_(2)N/G催化剂上CO_(2)RR和析氢反应的极限电位,讨论催化剂的活性和选择性。结果表明CO_(2)在低电位下容易生成HCOOH,施加高电位时可以生成CO、CH3OH和CH4并伴随着H2的生成。

关键词： CO_(2)还原反应电催化氮掺杂石墨烯水辅助氢穿梭反应机理密度泛函理论

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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

Approximate analytical solutions for threedimensional ascent trajectory of a solid-fuel launch vehicle with time-varying mass flow rate

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Chinese Journal of Aeronautics 2024年第10期37卷 275-293页

作者： Qi yu Wanchun CHEN Wenbin yu School of Astronautics Beihang UniversityBeijing 102206China

In the scenario that a solid-fuel launch vehicle maneuvers in outer space at high angles of attack and sideslip for energy management,Approximate Analytical Solutions(AAS)for the threedimensional(3D)ascent flight states are derived,which are the only solutions capable of considering time-varying Mass Flow Rate(MFR)at *** uneven MFR makes the thrust vary nonlinearly and thus increases the difficulty of the problem *** AAS are derived based on a 3D Generalized Ascent Dynamics Model(GADM)with a normalized mass as the independent *** simplify some highly nonlinear terms in the GADM,several approximate functions are introduced carefully,while the errors of the approximations relative to the original terms are regarded as minor ***,a finite series with positive and negative exponents,called Exponent-Symmetry Series(ESS),is proposed for function approximation to decrease the highest exponent in the AAS so as to reduce computer round-off *** calculate the ESS coefficients,a method of seeking the Optimal Interpolation Points(OIP)is proposed using the leastsquares-approximation *** to the artful design of the approximations,the GADM can be decomposed into two analytically solvable subsystems by a perturbation method,and thus the AAS are obtained ***,to help implement the AAS,two indirect methods for measuring the remaining mass and predicting the burnout time in flight are put forward using information from *** results verify the superiority of the AAS under the condition of time-varying MFR.

关键词： Approximate analytical solutions 3D ascent trajectory Solid-fuel launch vehicle Uneven thrust Energy management

Low-melting mixture solvents: extension of deep eutectic solvents and ionic liquids for broadening green solvents and green chemistry

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Green Chemical Engineering 2024年第4期5卷 409-417页

作者： yu Chen Zhiwu yu MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology Department of ChemistryTsinghua University

Green solvents such as water and ionic liquids(ILs) are pillars of the great mansion of green chemistry and green processing. Initially proposed as a new family of ILs,deep eutectic solvents(DESs) have received fast development in the past two decades. In this contribution,DESs are reviewed critically and the concept is extended to lowmelting mixture solvents(Lo MMSs),which cover all kinds of materials including ionic compounds,molecular compounds,and metals. Six classes of Lo MMSs are proposed as the new classification system and examples are given. Finally,several thermodynamic issues concerning Lo MMSs are discussed. Two new concepts,robustness of Lo MMSs and high-entropy Lo MMSs,are proposed.

关键词： Green solvents Deep eutectic solvents Low transition temperature mixture solvents Phase diagram EGaIn