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利益相关者共建模拟器“动”学模式培养应用型人才的探索
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作者 胡大立 肖乐明 《继续教育》 2012年第8期45-48,共4页
政府、企业、学校和行业等利益相关者,有效合作共建模拟器"动"学模式培养应用型人才,模拟器是将企业设施的操作、生产过程有效的移植到高等教育,模拟器"动"学模式让学生主动学习,在模拟实践中培养实际工作动手能力... 政府、企业、学校和行业等利益相关者,有效合作共建模拟器"动"学模式培养应用型人才,模拟器是将企业设施的操作、生产过程有效的移植到高等教育,模拟器"动"学模式让学生主动学习,在模拟实践中培养实际工作动手能力、创新能力和综合能力,模拟器融入"动"学模式可以实现多种企业设施的操作、生产"情景"。 展开更多
关键词 “动”学模式 应用型人才 模拟器 利益相关者
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四方联动构建航海模拟器“动”学教育模式
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作者 胡大立 肖乐明 《航海》 2012年第4期72-75,共4页
交通运输部、国家海事局和教育部等政府部门,合作办学的航运企业,航海院校,主导研制航海模拟器和航海教学的航海教育行业,利益相关者四方联动构建航海模拟器"动"学教育模式,培养应用型人才操作动手能力。
关键词 四方联 “动”学模式 模拟器 利益相关者
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枸杞多糖的生理功能及其在动物生产中的应用 被引量:8
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作者 刘杰 李柏珍 +1 位作者 伍树松 张桂杰 《动物营养学报》 CAS CSCD 北大核心 2023年第4期2129-2142,共14页
随着我国饲料“禁抗”时代的来临,天然的植物提取物逐渐成为一种新型替代抗生素的饲料添加剂。枸杞多糖是从枸杞及其副产物中提取出来的植物多糖类物质,主要由甘露糖、葡萄糖、半乳糖、阿拉伯糖、半乳糖醛酸和鼠李糖等组成,具有抗氧化... 随着我国饲料“禁抗”时代的来临,天然的植物提取物逐渐成为一种新型替代抗生素的饲料添加剂。枸杞多糖是从枸杞及其副产物中提取出来的植物多糖类物质,主要由甘露糖、葡萄糖、半乳糖、阿拉伯糖、半乳糖醛酸和鼠李糖等组成,具有抗氧化、抗肿瘤以及提高机体免疫力等多种生理功能,是枸杞及其副产物的主要活性成分。本文综述了枸杞多糖的主要制备工艺、生理功能和作用机制及其在动物生产中应用的研究进展,旨在为枸杞多糖作为新型饲料添加剂在动物生产中的应用提供参考。 展开更多
关键词 枸杞多糖 生理功能 作用机制 物生产
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不同放养密度对雪峰乌骨鸡生长性能、屠宰性能、血清生化和免疫指标的影响
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作者 王俣博 谢静 +6 位作者 姚亚铃 曲湘勇 郭松长 李梅春 刘加兴 刘志铁 贺长青 《动物营养学报》 CAS CSCD 北大核心 2024年第7期4329-4338,共10页
本试验旨在研究不同放养密度对雪峰乌骨鸡生长性能、屠宰性能、血清生化以及免疫指标的影响。选用健康的35日龄、体重一致的脱温雪峰乌骨鸡母鸡苗1620只,随机分为3个放养密度组,分别为低密度组(LSD组,60只/667 m^(2))、中密度组(MSD组,... 本试验旨在研究不同放养密度对雪峰乌骨鸡生长性能、屠宰性能、血清生化以及免疫指标的影响。选用健康的35日龄、体重一致的脱温雪峰乌骨鸡母鸡苗1620只,随机分为3个放养密度组,分别为低密度组(LSD组,60只/667 m^(2))、中密度组(MSD组,120只/667 m^(2))和高密度组(HSD组,180只/667 m^(2)),每组6个重复(林地面积500 m^(2)),LSD组每个重复45只,MSD组每个重复90只,HSD组每个重复135只。预试期7 d,正试期78 d。结果显示:1)LSD组雪峰乌骨鸡的平均日增重和料重比显著高于MSD组和HSD组(P<0.05)。2)LSD组宰前活重和屠体重均显著高于MSD组和HSD组(P<0.05)。3)LSD组血清中谷草转氨酶活性显著低于HSD组(P<0.05),LSD组和MSD组血清中碱性磷酸酶活性显著高于HSD组(P<0.05);LSD组血清中甘油三酯含量显著高于HSD组(P<0.05);HSD组血清中超氧化物歧化酶活性显著低于LSD组和MSD组(P<0.05)。4)HSD组血清中免疫球蛋白G、免疫球蛋白M、白细胞介素-2、白细胞介素-6和肿瘤坏死因子-α含量显著高于LSD组和MSD组(P<0.05),MSD组血清中免疫球蛋白A含量显著高于LSD组和HSD组(P<0.05)。由此可见,放养密度为60只/667 m^(2)时能有效提高雪峰乌骨鸡的生长性能,同时保证有较好的屠宰性能、抗氧化能力及免疫力。 展开更多
关键词 雪峰乌骨鸡 放养密度 生长性能 屠宰性能 血清指标
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思想品德课教学中开展社会实践活动模式的探析
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作者 王凤琴 《中国科教创新导刊》 2009年第12期51-51,共1页
随着思想品德课教学具有时代性、实践性、思想性。在思想品德课中增加社会实践活动,收集社会实践的模式,符合新课标提出的以德育为核心,以培养创新精神和实践能力为重点,全面推进素质教育,有利于学生的自我发展、自我完善、健全学生人格... 随着思想品德课教学具有时代性、实践性、思想性。在思想品德课中增加社会实践活动,收集社会实践的模式,符合新课标提出的以德育为核心,以培养创新精神和实践能力为重点,全面推进素质教育,有利于学生的自我发展、自我完善、健全学生人格,实现人生价值。 展开更多
关键词 实践活 生主体 关注社会 责任意识
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齿轮耦合的转子-轴承系统非线性动力特性的研究 被引量:31
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作者 张锁怀 李忆平 丘大谋 《机械工程学报》 EI CAS CSCD 北大核心 2001年第9期53-57,61,共6页
在考虑齿轮时变啮合刚度、齿侧间隙、脱齿、挤齿及齿背接触 等因素的情况下,建立了齿轮耦合的转子—滑动轴承系统的多自由度动力学模型。用数值方 法研究了该系统的质量不平衡响应,结果发现,由于齿轮时变啮合刚度的影响,随着转速的... 在考虑齿轮时变啮合刚度、齿侧间隙、脱齿、挤齿及齿背接触 等因素的情况下,建立了齿轮耦合的转子—滑动轴承系统的多自由度动力学模型。用数值方 法研究了该系统的质量不平衡响应,结果发现,由于齿轮时变啮合刚度的影响,随着转速的 增加,系统动力学响应首先由周期运动向准周期运动变化,当转速超过某一值时,系统的响应将由准周期运动发展为混沌运动;由于混沌运动,转子将沿齿轮中心线方向产生很大的变 形,脱齿、齿背接触及挤齿现象也将发生,可能导致系统产生破坏。 展开更多
关键词 齿侧间隙 时变啮合刚度 分岔 混沌 非线性 齿轮耦合 转子-轴承系统
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Alignment Techniques in Total Knee Arthroplasty:Where do We Stand Today?
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作者 Hemanta Dhungana Subhash Jangid Meghal Goyal 《Chinese Medical Sciences Journal》 CAS CSCD 2024年第3期224-233,共10页
Achieving optimal alignment in total knee arthroplasty(TKA)is a critical factor in ensuring optimal outcomes and long-term implant survival.Traditionally,mechanical alignment has been favored to achieve neutral post-o... Achieving optimal alignment in total knee arthroplasty(TKA)is a critical factor in ensuring optimal outcomes and long-term implant survival.Traditionally,mechanical alignment has been favored to achieve neutral post-operative joint alignment.However,contemporary approaches,such as kinematic alignments and hybrid techniques including adjusted mechanical,restricted kinematic,inverse kinematic,and functional alignments,are gaining attention for their ability to restore native joint kinematics and anatomical alignment,potentially leading to enhanced functional outcomes and greater patient satisfaction.The ongoing debate on optimal alignment strategies considers the following factors:long-term implant durability,functional improvement,and resolution of individual anatomical variations.Furthermore,advancements of computer-navigated and robotic-assisted surgery has augmented the precision in implant positioning and objective measurements of soft tissue balance.Despite ongoing debates on balancing implant longevity and functional outcomes,there is an increasing advocacy for personalized alignment strategies that are tailored to individual anatomical variations.This review evaluates the spectrum of various alignment techniques in TKA,including mechanical alignment,patient-specific kinematic approaches,and emerging hybrid methods.Each technique is scrutinized based on its fundamental principles,procedural techniques,inherent advantages,and potential limitations,while identifying significant clinical gaps that underscore the need for further investigation. 展开更多
关键词 total knee arthroplasty hybrid alignment functional alignment kinematic alignment alignment axes anatomical alignment mechanical alignment
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Sn nucleation and growth from Sn(II)dissolved in ethylene glycol:Electrochemical behavior and temperature effect
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作者 Kiem Van DO Hieu Van NGUYEN Tu Manh LE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2714-2732,共19页
Thermodynamic and kinetic aspects of Sn nucleation and growth processes onto a glassy carbon electrode from SnCl2·2H2O dissolved in ethylene glycol solutions were studied.Typical reduction and oxidation peaks obs... Thermodynamic and kinetic aspects of Sn nucleation and growth processes onto a glassy carbon electrode from SnCl2·2H2O dissolved in ethylene glycol solutions were studied.Typical reduction and oxidation peaks observed in voltammograms have demonstrated the capability of ethylene glycol solutions to electrodeposit Sn.The temperature-dependence of diffusion coefficient values derived from potentiodynamic and potentiostatic studies helped to determine and validate estimations of the activation energy for Sn(II)bulk diffusion.Chronoamperometric results have identified that,the suitable model to describe the early stage of Sn electrodeposition could be composed of Sn three-dimensional nucleation and diffusion-controlled growth and water reduction contributions,which was duly validated by theoretical and experimental approaches.From the model,typical kinetic parameters such as the nucleation frequency of Sn(A),number density of Sn nuclei(N_(0)),and diffusion coefficient of Sn(II)ions(D),were determined.The presence of Sn nuclei with excellent quality and their structures were verified using SEM,EDX,and XRD techniques. 展开更多
关键词 SN NUCLEATION growth ethylene glycol nucleation kinetics ELECTRODEPOSITION
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Machine learning molecular dynamics simulations of liquid methanol
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作者 Jie Qian Junfan Xia Bin Jiang 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第6期12-21,I0009,I0010,共12页
As the simplest hydrogen-bonded alcohol,liquid methanol has attracted intensive experimental and theoretical interest.However,theoretical investigations on this system have primarily relied on empirical intermolecular... As the simplest hydrogen-bonded alcohol,liquid methanol has attracted intensive experimental and theoretical interest.However,theoretical investigations on this system have primarily relied on empirical intermolecular force fields or ab initio molecular dynamics with semilocal density functionals.Inspired by recent studies on bulk water using increasingly accurate machine learning force fields,we report a new machine learning force field for liquid methanol with a hybrid functional revPBE0 plus dispersion correction.Molecular dynamics simulations on this machine learning force field are orders of magnitude faster than ab initio molecular dynamics simulations,yielding the radial distribution functions,selfdiffusion coefficients,and hydrogen bond network properties with very small statistical errors.The resulting structural and dynamical properties are compared well with the experimental data,demonstrating the superior accuracy of this machine learning force field.This work represents a successful step toward a first-principles description of this benchmark system and showcases the general applicability of the machine learning force field in studying liquid systems. 展开更多
关键词 liquid methanol molecular dynamics machine learning hydrogen bond force field
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Evolutionary analysis of green credit and automobile enterprises under the mechanism of dynamic reward and punishment based on government regulation
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作者 Yu Dong Xiaoyu Huang +1 位作者 Hongan Gan Xuyang Liu 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第5期49-62,I0007,共15页
To explore the green development of automobile enterprises and promote the achievement of the“dual carbon”target,based on the bounded rationality assumptions,this study constructed a tripartite evolutionary game mod... To explore the green development of automobile enterprises and promote the achievement of the“dual carbon”target,based on the bounded rationality assumptions,this study constructed a tripartite evolutionary game model of gov-ernment,commercial banks,and automobile enterprises;introduced a dynamic reward and punishment mechanism;and analyzed the development process of the three parties’strategic behavior under the static and dynamic reward and punish-ment mechanism.Vensim PLE was used for numerical simulation analysis.Our results indicate that the system could not reach a stable state under the static reward and punishment mechanism.A dynamic reward and punishment mechanism can effectively improve the system stability and better fit real situations.Under the dynamic reward and punishment mechan-ism,an increase in the initial probabilities of the three parties can promote the system stability,and the government can im-plement effective supervision by adjusting the upper limit of the reward and punishment intensity.Finally,the implementa-tion of green credit by commercial banks plays a significant role in promoting the green development of automobile enter-prises. 展开更多
关键词 automobile enterprises green credit system dynamics reward and punishment mechanism
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Study on the Mechanism of Nanopatterning in Printed Electronics Based on Molecular Dynamics Simulation
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作者 HUANG Hai-yang LI Yan ZHANG Run-liang 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期237-244,共8页
In order to research the feasibility of using the selective adsorption principle to achieve automatic shaping of nano patterns,in this study,using the liquid gallium as the conductive ink and graphene as the printing ... In order to research the feasibility of using the selective adsorption principle to achieve automatic shaping of nano patterns,in this study,using the liquid gallium as the conductive ink and graphene as the printing plate surface,by changing the surface wettability of patterned areas on the nanoscale of graphene printed boards,the automatic formation of liquid gallium patterns on the graphene printed plate surface was simulated.The results indicated that liquid gallium can achieve automatic patterning on the surface of graphene patterned areas;the greater the interaction energy between gallium and carbon atoms,the clearer the pattern;gallium liquid is prone to remain in complex local positions of the pattern,making it difficult to shape the pattern;if the spacing between adjacent pattern lines is too large or too small,it will result in residual gallium liquid between the lines;increasing the thickness of the gallium film will cause the pattern to expand beyond the boundary,but increasing the thickness of the gallium film can also enhance the thickness and uniformity of the pattern lines.In summary,the principle of selective adsorption can be used to achieve the automatic formation of nano patterns,and the pattern formation effect is influenced by factors such as atomic interaction energy and pattern configuration. 展开更多
关键词 Molecular dynamics Liquid gallium GRAPHENE Pattern forming
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0D-1D coupling model and 3D fluid-structure interaction model based on coronary CT angiography for displaying hemodynamic characteristics of coronary artery stenosis
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作者 LIU Shanfeng LU Xiaochen +1 位作者 TIAN Hao WU Huiqun 《中国医学影像技术》 CSCD 北大核心 2024年第8期1236-1241,共6页
Objective To observe value of 0D-1D coupling model and 3D fluid-structure interaction(FSI)model based on coronary CT angiography(CCTA)for displaying hemodynamic characteristics of coronary artery stenosis.Methods Base... Objective To observe value of 0D-1D coupling model and 3D fluid-structure interaction(FSI)model based on coronary CT angiography(CCTA)for displaying hemodynamic characteristics of coronary artery stenosis.Methods Based on CCTA data of the stenosed left anterior descending branch(LAD)in a patient with coronary heart disease,an 0D-1D coupling model and 3D FSI model were built,respectively.Then hemodynamic characteristic indexes,including the pressure,flow velocity and wall shear stress(WSS)were obtained in every 0.01 s during 1 s at 5 sampling points(i.e.sampling point 1—5)using these 2 models,respectively,and the consistencies of the results between models were evaluated with Spearman correlation coefficient r s.Results The time consuming for construction of 0D-1D coupling model and 3D FSI model was 0.033 min and 704 min,respectively.Both models showed basically distribution of the pressure,flow velocity and WSS of the stenosed LAD.For more details,the pressure at the stenosed segment of LAD and the proximal segment of stenosis were both higher,which gradually decreased at the distal segment of stenosis,and the flow velocity at the proximal segment of stenosis was in a relatively slow and uniform condition,with significantly increased flow velocity and WSS at the stenosed segment.Compared with 3D FSI model,0D-1D vascular coupling model was relatively unrefined and lack of distal flow lines when displaying blood flow velocity.For sampling point 2 at the stenosed segment of LAD,no significant consistency for pressure between 2 models was found(P=0.118),but strong consistency for the flow velocity and WSS(r s=0.730,0.807,both P<0.05).The consistencies of pressure,flow velocity and WSS between 2 models at the proximal and distal segment of stenosis,i.e.1,3—5 sampling points were week to moderate(r s=0.237—0.669,all P<0.05).Conclusion 0D-1D coupling model exhibited outstanding computational efficiency and might provide relatively reasonable results,while 3D FSI model showed higher accuracy for details and streamline when simulating LAD stenosis. 展开更多
关键词 coronary stenosis HEMODYNAMICS coronary angiography tomography X-ray computed
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Anesthesia Management in Hereditary Pheochromocytoma and Paraganglioma:Updated Insights into Clinical Features and Perioperative Care
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作者 Yao-Han Li Le Shen 《Chinese Medical Sciences Journal》 CAS CSCD 2024年第3期217-223,共7页
Approximately 40%of pheochromocytoma and paraganglioma(PPGL)cases are familial,typically presenting earlier with more complex symptoms.This paper synthesizes literature and guidelines to inform on clinical characteris... Approximately 40%of pheochromocytoma and paraganglioma(PPGL)cases are familial,typically presenting earlier with more complex symptoms.This paper synthesizes literature and guidelines to inform on clinical characteristics and perioperative care for PPGL.Pheochromocytoma in von Hippel-Lindau(VHL)disease exhibits heightened secretion activity without significant perioperative hemodynamic changes.Tumors in multiple endocrine neoplasia type 2(MEN2)have a stronger endocrine function,which may induce hemodynamic fluctuations during surgery Therefore,pheochromocytoma screening is essential at all stages of MEN2.Neurofibromatosis type 1(NF1)often presents multisystem lesions and can result in dificult airway.Pheochromocytoma should be evaluated when NF1 patients present hypertension.Pheochromocytoma and paraganglioma type 5 may present multiple lesions of pheochromocytoma or paraganglioma.In summary,hereditary PPGLs may present with severe lesions in other systems,beyond tumor function.A multi-disciplinary team(MDT)approach is often invaluable in perioperative management. 展开更多
关键词 PHEOCHROMOCYTOMA PARAGANGLIOMA genetic disease anesthetic management HEMODYNAMIC perioperative care
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Solution for Output Coordination Equations of Several Typical Parallel Six-Dimensional Acceleration Sensing Mechanisms
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作者 ZHANG Xianzhu YOU Jingjing ZHANG Yuanwei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期96-102,共7页
Aiming at the problem that it is difficult to generate the dynamic decoupling equation of the parallel six-dimensional acceleration sensing mechanism,two typical parallel six-dimensional acceleration sensing mechanism... Aiming at the problem that it is difficult to generate the dynamic decoupling equation of the parallel six-dimensional acceleration sensing mechanism,two typical parallel six-dimensional acceleration sensing mechanisms are taken as examples.By analyzing the scale constraint relationship between the hinge points on the mass block and the hinge points on the base of the sensing mechanism,a new method for establishing the dynamic equation of the sensing mechanism is proposed.Firstly,based on the scale constraint relationship between the hinge points on the mass block and the hinge points on the base of the sensing mechanism,the expression of the branch rod length is obtained.The inherent constraint relationship between the branches is excavated and the branch coordination closed chain of the“12-6”configuration is constructed.The output coordination equation of the sensing mechanism is successfully derived.Secondly,the dynamic equations of“12-4”and“12-6”configurations are constructed by the Newton-Euler method,and the forward decoupling equations of the two configurations are solved by combining the dynamic equations and the output coordination equations.Finally,the virtual prototype experiment is carried out,and the maximum reference errors of the forward decoupling equations of the two configuration sensing mechanisms are 4.23%and 6.53%,respectively.The results show that the proposed method is effective and feasible,and meets the real-time requirements. 展开更多
关键词 six-dimensional acceleration sensor parallel mechanism topological configuration coordination equation dynamics
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Enhancing Na^(+) diffusion dynamics and structural stability of O3-NaMn_(0.5)Ni_(0.5)O_(2)cathode by Sc and Zn dual-substitution
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作者 Bin-bin WANG Yi-ming FENG +8 位作者 Xin LUO Qun HUANG Zi-xing HOU Ya-qin WU Peng-yu WANG Yu-yang QI Qing-fei MENG Wei-feng WEI Liang-jun ZHOU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3344-3357,共14页
Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural ... Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural stability of NaMN was investigated.The physicochemical characterizations suggest that the introduction of Sc and Zn broaden Na^(+) diffusion channels and weaken the Na—O bonds,thereby facilitating the diffusion of sodium ions.Simulations indicate that the Sc and Zn dual-substitution decreases the diffusion barrier of Na-ions and improves the conductivity of the material.The dual-substituted NaMn_(0.5)Ni_(0.4)Sc_(0.04)Zn_(0.04)O_(2)(Na MNSZ44)cathode delivers impressive cycle stability with capacity retention of 71.2%after 200 cycles at 1C and 54.8%after 400 cycles at 5C.Additionally,the full cell paired with hard carbon anode exhibits a remarkable long-term cycling stability,showing capacity retention of 64.1%after 250 cycles at 1C.These results demonstrate that Sc and Zn dual-substitution is an effective strategy to improve the Na^(+) diffusion dynamics and structural stability of NaMN. 展开更多
关键词 layered oxide cathode Sc and Zn dual-substitution structural stability Na^(+)diffusion dynamics
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Improvement Mechanism of Adhesion Performance of Anti-stripping Agents and Coupling Agents on Asphalt-Aggregate Interface Based on Molecular Dynamics
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作者 SONG Jing XIE Jianguang DAI Zexinyu 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期111-120,共10页
This study examined the mechanisms for improving the adhesion performance of the asphalt-aggregate interface with two anti-stripping agents and two coupling agents.The investigation of contact behavior between various... This study examined the mechanisms for improving the adhesion performance of the asphalt-aggregate interface with two anti-stripping agents and two coupling agents.The investigation of contact behavior between various asphalt-aggregate surfaces was conducted using molecular dynamics(MD)simulations.The interaction energy and the relative concentration distribution were employed as the parameters to analyze the enhancement mechanisms of anti-stripping agents and coupling agents on the asphalt-aggregate interface.Results indicated that the adhesion at the asphalt-aggregate interface could be strengthened by both anti-stripping agents and coupling agents.Anti-stripping agents primarily improve adhesion through the reinforcement of electrostatic attraction,while coupling agents primarily upgrade adhesion by strengthening the van der Waals.Hence,the molecular dynamics modeling and calculation techniques presented in this study can be utilized to elucidate the development mechanism of the asphalt-aggregate interface through the use of anti-stripping agents and coupling agents. 展开更多
关键词 asphalt-aggregate interface adhesion performance anti-stripping agents coupling agents molecular dynamics
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Characterization of the dissociation pathways of dichloromethane and glutathione in dichloromethane dehalogenase
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作者 Gao Xudan Zhang Huizhu Mei Ye 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第4期651-660,共10页
Dichloromethane(DCM)dehalogenase stands as a crucial enzyme implicated in the degradation of methylene chloride across diverse environmental and biological contexts.However,the unbinding pathways of ligands from DCM d... Dichloromethane(DCM)dehalogenase stands as a crucial enzyme implicated in the degradation of methylene chloride across diverse environmental and biological contexts.However,the unbinding pathways of ligands from DCM dehalogenase remain unexplored.In order to gain a deeper understanding of the binding sites and dissociation pathways of dichloromethane(DCM)and glutathione(GSH)from the DCM dehalogenase,random accelerated molecular dynamics(RAMD)simulations were performed,in which DCM and GSH were forced to leave the active site.The protein structure was predicted using Alphafold2,and the conformations of GSH and DCM in the binding pocket were predicted by docking.A long equilibrium simulation was conducted to validate the structure of the complex.The results show that GSH is most commonly observed in three main pathways,one of which is more important than the other two.In addition,DCM was observed to escape along a unique pathway.The key residues and protein helices of each pathway were identified.The results can provide a theoretical foundation for the subsequent dissociation mechanism of DCM dehalogenase. 展开更多
关键词 DCM dehalogenase GSH Alphafold2 RAMD unbinding pathways
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Rate Law for Photoelectrochemical Water Splitting Over CuO
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作者 Bo-Yuan Gao Wen-HuaLeng 《电化学(中英文)》 CAS 北大核心 2024年第8期17-27,共11页
Photocatalytic splitting of water over p-type semiconductors is a promising strategy for production of hydrogen.However,the determination of rate law is rarely reported.To this purpose,copper oxide(CuO)is selected as ... Photocatalytic splitting of water over p-type semiconductors is a promising strategy for production of hydrogen.However,the determination of rate law is rarely reported.To this purpose,copper oxide(CuO)is selected as a model photocathode in this study,and the photogenerated surface charge density,interfacial charge transfer rate constant and their relation to the water reduction rate(in terms of photocurrent)were investigated by a combination of(photo)electrochemical techniques.The results showed that the charge transfer rate constant is exponential-dependent on the surface charge density,and that the photocurrent equals to the product of the charge transfer rate constant and surface charge density.The reaction is first-order in terms of surface charge density.Such an unconventional rate law contrasts with the reports in literature.The charge density-dependent rate constant results from the Fermi level pinning(i.e.,Galvani potential is the main driving force for the reaction)due to accumulation of charge in the surface states and/or Frumkin behavior(i.e.,chemical potential is the main driving force).This study,therefore,may be helpful for further investigation on the mechanism of hydrogen evolution over a CuO photocathode and for designing more efficient CuO-based photocatalysts. 展开更多
关键词 CUO Photoelectrochemical water splitting Electrochemical impedance spectroscopy Rate law Kinetics of photogenerated carriers
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Temperature-Induced Unfolding Pathway of Staphylococcal Enterotoxin B:Insights from Circular Dichroism and Molecular Dynamics Simulation
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作者 LIU Ji ZHANG Shiyu +1 位作者 ZENG Yu DENG Yi 《食品科学》 EI CAS CSCD 北大核心 2024年第18期55-76,共22页
In this study,circular dichroism(CD)and molecular dynamics(MD)simulation were used to investigate the thermal unfolding pathway of staphylococcal enterotoxin B(SEB)at temperatures of 298–371 and 298–500 K,and the re... In this study,circular dichroism(CD)and molecular dynamics(MD)simulation were used to investigate the thermal unfolding pathway of staphylococcal enterotoxin B(SEB)at temperatures of 298–371 and 298–500 K,and the relationship between the experimental and simulation results were explored.Our computational findings on the secondary structure of SEB showed that at room temperature,the CD spectroscopic results were highly consistent with the MD results.Moreover,under heating conditions,the changing trends of helix,sheet and random coil obtained by CD spectral fitting were highly consistent with those obtained by MD.In order to gain a deeper understanding of the thermal stability mechanism of SEB,the MD trajectories were analyzed in terms of root mean square deviation(RMSD),secondary structure assignment(SSA),radius of gyration(R_(g)),free energy surfaces(FES),solvent-accessible surface area(SASA),hydrogen bonds and salt bridges.The results showed that at low heating temperature,domain Ⅰ without loops(omitting the mobile loop region)mainly relied on hydrophobic interaction to maintain its thermal stability,whereas the thermal stability of domain Ⅱ was mainly controlled by salt bridges and hydrogen bonds.Under high heating temperature conditions,the hydrophobic interactions in domain Ⅰ without loops were destroyed and the secondary structure was almost completely lost,while domain Ⅱ could still rely on salt bridges as molecular staples to barely maintain the stability of the secondary structure.These results help us to understand the thermodynamic and kinetic mechanisms that maintain the thermal stability of SEB at the molecular level,and provide a direction for establishing safer and more effective food sterilization processes. 展开更多
关键词 staphylococcal enterotoxin B circular dichroism molecular dynamics simulations temperature-induced unfolding
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Temperature-feedback two-photon-responsive metal-organic frameworks for efficient photothermal therapy
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作者 Xianshun Sun Xin Lu +4 位作者 Wenyao Duan Bo Li Yupeng Tian Dandan Li Hongping Zhou 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第6期53-59,I0011,共8页
The realization of real-time thermal feedback for monitoring photothermal therapy(PTT)under near-infrared(NIR)light irradiation is of great interest and challenge for antitumor therapy.Herein,by assembling highly effi... The realization of real-time thermal feedback for monitoring photothermal therapy(PTT)under near-infrared(NIR)light irradiation is of great interest and challenge for antitumor therapy.Herein,by assembling highly efficient photothermal conversion gold nanorods and a temperature-responsive probe((E)-4-(4-(diethylamino)styryl)-1-methylpyridin-1-ium,PyS)within MOF-199,an intelligent nanoplatform(AMPP)was fabricated for simultaneous chemodynamic therapy and NIR light-induced temperature-feedback PTT.The fluorescence intensity and temperature of the PyS probe are linearly related due to the restriction of the rotation of the characteristic monomethine bridge.Moreover,the copper ions resulting from the degradation of MOF-199 in an acidic microenvironment can convert H_(2)O_(2)into•OH,resulting in tumor ablation through a Fenton-like reaction,and this process can be accelerated by increasing the temperature.This study establishes a feasible platform for fabricating highly sensitive temperature sensors for efficient temperature-feedback PTT. 展开更多
关键词 metal-organic framework TWO-PHOTON temperature feedback photothermal therapy chemodynamic therapy
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