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Chinese Chemical Letters 2021年第11期32卷 3591-3595页

作者： Xuyun Gao Bo Li Xuzhuo Sun Baofan Wu Yanping Hu zhichao ning Jun Li ning Wang College of Chemistry and Chemical Engineering Henan University of TechnologyZhengzhou 450001China Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi'an 710069China

Crystalline engineering and heterostructure have attracted much attention as effective strategies to improve the electrocatalytic activity for hydrogen evolution reaction(HER).In this study,a new heterostructure catalyst(Ru/RuS_(2)@N-rGO)with low crystallinity was fabricated by a simple and low-temperature method for HER in alkaline solution,applying the Na_(2)SO_(4)as S source and polypyrrole as N *** through the controllable crystalline engineering and composition ratio of Ru and RuS_(2),the Ru/RuS_(2)@N-rGO heterocatalyst at the calcining 500°C revealed highly efficient HER activity with overpotential 18 mV at a current density 10 mA/cm^(2)and remarkable stability for 24 h in 1.0 mol/L *** work provides a facile and effective method in designing advanced electrocatalysts for HER in the alkaline electrolytes by synergistically structural and component modulations.

关键词： Low crystallinity Ru/RuS_(2)heterostructure Graphene Electrocatalytic hydrogen evolution Alkaline solution

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基于系统工程的技术成熟度评价与应用

科技管理研究 2023年第11期43卷 47-56页

作者：杨卓鹏江庆平杨晖宁智超中国航天系统科学与工程研究院北京100048 中国人民解放军96901部队北京100094

针对技术成熟度评价要素耦合、评价过程复杂等特点,将系统工程方法应用于技术成熟度评价。首先建立系统工程“V”模型与技术成熟度等级的映射关系,其次通过霍尔三维结构、物理-事理-人理方法论对技术成熟度评价要素进行多维度分解,并建... 详细信息

针对技术成熟度评价要素耦合、评价过程复杂等特点,将系统工程方法应用于技术成熟度评价。首先建立系统工程“V”模型与技术成熟度等级的映射关系,其次通过霍尔三维结构、物理-事理-人理方法论对技术成熟度评价要素进行多维度分解,并建立技术成熟度等级与技术风险的交互关系,围绕技术状态、集成状态、环境状态建立技术成熟度评价推理规则,并给出融合上述系统工程方法的技术成熟度评价综合集成研讨厅框架。以某型无人机装备技术成熟度评价实践证明上述方法的工程有效性,并可向其他装备推广应用。

关键词：技术成熟度系统工程技术风险知识表达无人机

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六自由度果实采摘机械手及其控制系统的设计

农机化研究 2010年第9期32卷 111-113,117页

作者：宁志超崔天时李广军东北农业大学工程学院哈尔滨150030 尚志市电业局黑龙江尚志150060

目前我国农业机械化水平相对于欧美的一些发达国家很低,因此加快我国的农业机械化进程,是实现我国农业现代化的必由之路。基于ATmega16的六自由度果实采摘机械手就是提高我国农机化进程一项有力措施。为此,主要介绍了基于AVR系列单片机... 详细信息

目前我国农业机械化水平相对于欧美的一些发达国家很低,因此加快我国的农业机械化进程,是实现我国农业现代化的必由之路。基于ATmega16的六自由度果实采摘机械手就是提高我国农机化进程一项有力措施。为此,主要介绍了基于AVR系列单片机—ATmega16L的控制器的设计,以及机械手整体结构的组成设计。机械系统的设计采用模块化的设计方案,即将功能分解,降低模块之间的耦合性。硬件系统主要由6路伺服电机、金属支架组件以及控制器构成;控制器分别从硬件和软件两方面进行设计,并通过实验验证了六自由度采摘机械手的可行性。

关键词：果实 ATmega168 伺服电机自由度模块化

腺癌保乳术后调强放疗与三维适形放疗的疗效比较

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癌症进展 2017年第3期15卷 321-324页

作者：刘铁斌宁智超田平艳解放军201医院放疗科辽宁大连116021

目的比较乳腺癌保乳术后调强放疗(IMRT)与三维适形放疗(3D-CRT)的疗效、不良反应及对基质金属蛋白酶-9(MMP-9)和基质金属蛋白酶组织抑制剂-1(TIMP-1)的影响。方法选择96例接受乳腺癌保乳术的女性患者,按照随机数字表法将患者随机分为对... 详细信息

目的比较乳腺癌保乳术后调强放疗(IMRT)与三维适形放疗(3D-CRT)的疗效、不良反应及对基质金属蛋白酶-9(MMP-9)和基质金属蛋白酶组织抑制剂-1(TIMP-1)的影响。方法选择96例接受乳腺癌保乳术的女性患者,按照随机数字表法将患者随机分为对照组和观察组,每组各48例。对照组予以3D-RCT,观察组予以IMRT,处方剂量均为50 Gy/25次。比较两组的照射剂量、不良反应、美容效果及治疗前后的血清MMP-9和TIMP-1水平。结果观察组计划靶区(PTV)的V105%、V110%及V115%明显低于对照组(P﹤0.01),观察组患侧肺脏及左侧病灶者心脏接受的照射剂量明显低于对照组(P﹤0.01);观察组的皮肤反应率为12.5%(6/48),低于对照组的29.2%(14/48),差异有统计学意义(P﹤0.05);观察组美容优良率为97.9%(47/48),高于对照组的83.3%(40/48),差异有统计学意义(P﹤0.05)。放疗后,两组患者的MMP-9及MMP-9/TIMP-1均较本组治疗前降低,但组间比较差异无统计学意义(P﹥0.05)。结论与3D-CRT相比,IMRT的PTV适形度和剂量均匀性较好,可降低危及器官的受照剂量,皮肤反应较少且美容效果好,值得临床推广。

关键词：乳腺癌保乳术调强放疗蕾三维适形放疗 MMP-9 TIMP-1

Frequency-constrained Unit Commitments with Linear Rules Extracted from Simulation Results Considering Regulations from Battery Storage

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Journal of Modern Power Systems and Clean Energy 2023年第4期11卷 1041-1052页

作者： Jiawei Zhang zhichao Chen ning Zhang Xianfeng Zhang State Key Lab of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Science and Technology Research Institute ChinaThreeGorgesCorporationBeijing100038China

Heavy renewable penetrations and high-voltage cross-regional transmission systems reduce the inertia and critical frequency stability of power systems after ***,the power system operators should ensure the frequency nadirs after possible disturbances are within the set restriction,e.g.,0.20 *** methods utilize linearized and simplified control models to quantify the frequency nadirs and achieve frequency-constrained unit commitments(FCUCs).However,the simplified models are hard to depict the frequency responses of practical units after ***,they usually neglect the regulations from battery *** paper achieves FCUCs with linear rules extracted from massive simulation *** simulate the frequency responses on typical thermal-hydro-storage systems under diverse unit online ***,we extract the rules of frequency nadirs after disturbances merely with linear support vector machine to evaluate the frequency stability of power *** algorithm holds a high accuracy in a wide range of frequency ***,we apply the rules to three typical cases to show the influences of frequency constraints on unit commitments.

关键词： Frequency regulation unit commitment machine learning rule extraction primary frequency regulation energy storage support vector machine

The crystallographic texture and dependent mechanical properties of the CrCoNi medium-entropy alloy by laser remelting strategy

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Journal of Materials Science & Technology 2022年第16期111卷 245-255页

作者： Pengsheng Xue Lida Zhu Jinsheng ning Peihua Xu Shuhao Wang zhichao Yang Yuan Ren Guiru Meng School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China

Laser remelting(LR)has attracted widespread attention in recent years as an effective method to reduce internal defects and improve the surface quality of additively manufactured(AM)*** the present study,three different LR inter-layer scanning strategies(LR0,LR90 and LR45)and their effects on the porosity,microstructure,crystallographic texture and related mechanical properties of parts have been *** microscope,X-ray diffraction,and scanning electron microscope were used as characterization *** the LR90 sample,it shows obvious{111}texture and strongpreferred orientation along the scanning direction(SD),while the 0°offset and the 45°rotation of LR scanning strategy form a finer microstructure and weak crystallographic ***,the mechanical properties of the LR sample are improved compared with the sample only by laser metal deposition(LMD),and a combination of higher strength and optimal uniform elongation is obtained in the LR45 *** overall results show that a reasonable LR scanning strategy can reduce the anisotropy of AM parts and improve their mechanical properties.

关键词： CrCoNi Laser remelting Porosity Crystallographic orientation Mechanical properties

pH- and H_(2)O_(2)-sensitive drug delivery system based on sodium xanthate:Dual-responsive supramolecular vesicles from one functional group

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Chinese Chemical Letters 2022年第10期33卷 4563-4566页

作者： Ziyan Shen ning Ma Feng Wang Jiaming Ren Chenxi Hou Shuang Chao Yuxin Pei zhichao Pei Shaanxi Key Laboratory of Natural Products&Chemical Biology College of Chemistry&PharmacyNorthwest A&F UniversityYangling 712100China

Nano-drug delivery systems with multiple stimulus-responsive capabilities have superior response performance and efficient drug ***,it is sophisticated to construct multiple stimulus-responsive systems where the two or more functional groups need to be introduced ***,one functional group with pH and H2O2 stimulus responsiveness,has significant potential applications for building dual-responsive drug delivery ***,we present a novel dual stimuli-responsive supramolecular drug delivery system by using sodium xanthate derivative(SXD)as guest molecule and quaternary ammonium capped pillar[5]arene(QAP5)as host molecule through host-guest interaction on the basis of electrostatic *** amphiphile QAP5⊃SXD could self-assemble into vesicles to efficiently load the anti-cancer drug *** experimental results showed that QAP5⊃SXD nanoparticles could achieve efficient drug delivery and controlled release in the tumor *** experiments proved that DOX@QAP5⊃SXD nanoparticles could significantly improve the anticancer efficiency of free DOX on cancer *** present study provides an efficient strategy to develop supramolecular nanocarriers with dual-responsiveness in one functional group for controlled drug release.

关键词： Pillararene Sodium xanthate Host-guest interaction pH-and H_(2)O_(2)-dual responsive Controllable drug delivery

Fast prototype and rapid construction of three-dimensional and multi-scaled pitcher for controlled drainage by systematic biomimicry

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International Journal of Extreme Manufacturing 2024年第3期6卷 489-503页

作者： Tao Shen ning Li Shijie Liu Cunlong Yu Chengqi Zhang Kang Yang Xingfei Li Ruochen Fang Lei Jiang zhichao Dong Research Institute for Frontier Science Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education BeijingSchool of ChemistryBeihang UniversityBeijing 100191People’s Republic of China CAS Key Laboratory of Bio-inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190People’s Republic of China CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 100083People’s Republic of China School of Future Technology&School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijing 101407People’s Republic of China School of Chemistry and Materials Science University of Science and Technology of China230026 HefeiAnhuiPeople’s Republic of China Suzhou Institute for Advanced Research University of Science and Technology of China215123 SuzhouJiangsuPeople’s Republic of China State Key Laboratory of Precision Measuring Technology and Instruments Tianjin University300072 TianjinPeople’s Republic of China

Biomimetic materials that use natural wisdom to solve practical problems are developing *** trend for systematic biomimicry is towards in-situ characterization of naturalcreatures with high spatial ***,rapid reconstruction of digital twin models with the same complex features as the prototype is ***,it faces bottlenecks and limits in fast characterization and fabrication,precise parameter optimization,geometricdeviations control,and quality *** solve these challenges,here,we demonstrate astate-of-the-art method taking advantage of micro-computed tomography and three-dimensional printing for the fast characterization of the pitcher plant Nepenthes x ventrata and fabrication of its biomimetic model to obtain a superior drainage controller with multiscale structures withprecise surface morphology optimization and geometric deviation ***-rupture-based drainage dynamic and mechanisms are characterized by x-ray and high-speed videography,which determines the crucial structures for unique *** the optimized artificial pitchers are further developed into sustained drainage devices with novel applications,such as detection,reaction,and smoke control.

关键词： systematic biomimicry biomimetic materials Micro-CT drainage digital twin

Experimental study on sand production and coupling response of silty hydrate reservoir with different contents of fine clay during depressurization

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Petroleum 2023年第1期9卷 72-82页

作者： Xiangyu Fang Dianheng Yang Fulong ning Linjie Wang zhichao Liu Yanjiang Yu Wenwei Xie Hongfeng Lu Yanlong Li Meng Xu Faculty of Engineering China University of GeosciencesWuhan430074China Anhui Nuclear Exploration Technology Central Institute Wuhu241000China National Center for International Research on Deep Earth Drilling and Resource Development China University of GeosciencesWuhan430074China MLR Key Laboratory of Marine Mineral Resources Guangzhou Marine Geological SurveyGuangzhou510075China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao266071China

To further understand the characteristics of clay and sand production(hereafter collectively referred to as sand production)and to provide optimization designs of sand control schemes are critical for gas production from clayey silt natural gas hydrate reservoirs in the South China ***,gas-water-sand production behavoirs and coupling reservoir subsidence characteristics before,during,and after hydrate dissociation of the clayey silt hydrate reservoirs with different clay contents(5%,10%,15%,20%,25%,and 30%)have been studied through a self-developed experimental *** results show that with the increase of clay content,the total mass of sand production first increases and then decreases,and it reaches maximum when the clayey content is 20%.The sand production is the lowest before hydrate dissociation and increases significantly during hydrate dissociation,which mainly occurs in the high-speed gas and water production stage at the beginning of hydrate *** hydrate dissociation,the sand production decreases *** the whole depressurization process,the clay and free sand particles generally move to the sand outlet due to the fluid driving force and overlying stress ***,for conditions of high clay contents,those particles fail to pass through the sand control screen and gradually accumulate and block the screen by forming a mud cake,which greatly reduce the permeability of the screen and limite sand production as well as gas and water *** research lays a foundation for sand production prediction and sand control scheme selection during gas recovery from clayey silty hydrate reservoirs that greatly need to consider a balance between sand control and gas productivity.

关键词： Natural gas hydrate Clayey silt reservoir Clay content Depressurization Sand production Sand control

Effect of hydrophilic silica nanoparticles on hydrate formation: Insight from the experimental study

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Journal of Energy Chemistry 2019年第3期28卷 90-100页

作者： Ren Wang Tianle Liu Fulong ning Wenjia Ou Ling Zhang Zhen Wang Li Peng Jiaxin Sun zhichao Liu Tianshu Li Huicui Sun Guosheng Jiang Faculty of Engineering China University of Geosciences CNPC Drilling Research Institute Department of Civil and Environmental Engineering The George Washington University

Invasion of drilling fluid into natural gas hydrate deposits during drilling might damage the reservoir,induce hydrate dissociation and then cause wellbore instability and distortion of the data from well logging. Adding nanoparticles into drilling fluid is an effective method in reducing the invasion of drilling fluid and enhancing borehole stability. However, the addition of nanoparticles might also introduce hydrate formation risk in borehole because they can act as the "seeds" for hydrate nucleation. This paper presents an experimental study of the effect of hydrophilic silica nanoparticle on gas hydrate formation in a dynamic methane/liquid-water system. In the experiment, the ultrapure water with and without1.0 wt%–6.0 wt% concentrations of silica nanoparticles, grain sizes of 20 and 50 nm, were pressurized by methane gas under varied conditions of temperature and pressure. The induction time, the gas consumption, and the average rate of gas consumption in the system were measured and compared to those in ultrapure water. The results show that a concentration of 4.0 wt% hydrophilic SiO_2 particles with a grain size of 50 nm has a relatively strong inhibition effect on hydrate formation when the initial experimental condition is 5.0 °C and 5.0 MPa. Compared to ultrapure water, the hydrophilic nano-SiO_2 fluid increases the induction time for hydrate formation by 194% and decreases the amount and average rate of hydrate formation by 10% and 17%, respectively. This inhibition effect may be attributed to the hydrophilicity,amount and aggregation of silica nanoparticle according to the results of water activity and zeta potential measurements. Our work also elucidates hydrophilic, instead of hydrophobic, nanoparticles can be added to the drilling fluid to maintain wellbore stability and to protect the hydrate reservoir from drilling mud damage, because they exhibit certain degree of hydrate inhibition which can reduce the risk of hydrate reformation and aggregation

关键词： Hydrate drilling fluid Hydrophilic nano-SiO2 Concentration Grain size Hydrate formation Inhibition mechanism