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Research on the flow stability and noise reduction characteristics of quasi-periodic elastic support skin

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Defence Technology（防务技术） 2024年第3期33卷 222-236页

作者： Lu Chen Shao-gang Liu Dan Zhao Li-qiang Dong Kai Li Shuai Tang jin Cui hong Guo Department of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin150001China

To enhance flow stability and reduce hydrodynamic noise caused by fluctuating pressure,a quasiperiodic elastic support skin composed of flexible walls and elastic support elements is proposed for fluid noise *** arrangement of the elastic support element is determined by the equivalent periodic distance and quasi-periodic *** this paper,a dynamic model of skin in a fluid environment is *** influence of equivalent periodic distance and quasi-periodic coefficient on flow stability is *** results suggest that arranging the elastic support elements in accordance with the quasi-periodic law can effectively enhance flow ***,the hydrodynamic noise calculation results demonstrate that the skin exhibits excellent noise reduction performance,with reductions of 10 dB in the streamwise direction,11 dB in the spanwise direction,and 10 dB in the normal *** results also demonstrate that the stability analysis method can serve as a diagnostic tool for flow fields and guide the design of noise reduction structures.

关键词： Flow stability Quasi-period Flexible wall Elastic support element Hydrodynamic noise

Electrochemical reconstruction: a new perspective on Sn metal-organic complex microbelts as robust anode for lithium storage

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Rare Metals 2024年第1期43卷 76-86页

作者： jin-Ke Shen Nai-Teng Wu Li-Yuan Wang Gang Jiang Dong-Lei Guo jin Li Gui-Long Liu hong-Yu Mi Huan Pang Xian-Ming Liu Key Laboratory of Function-oriented Porous Materials of Henan Province College of Chemistry and Chemical EngineeringLuoyang Normal UniversityLuoyang 471934China State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources School of Chemical Engineering and TechnologyXinjiang UniversityUrumqi 830046China School of Chemistry and Chemical Engineering Institute for Innovative Materials and EnergyYangzhou UniversityYangzhou 225009JiangsuChina

Tin-based materials with high theoretical capacity and suitable working voltage are ideal anode materials for lithium-ion batteries(LIBs). However, to overcome their shortcomings(volume expansion and inferior stability), the preparation processes are usually complicated and expensive. Herein, a tin-based metal-organic complex(tin 1,2-benzenedicarboxylic acid, Sn-BDC)with one-dimensional microbelt morphology is synthesized by a facile, rapid and low-cost co-precipitation method, and served as anode material for LIBs without any post-treatment. Sn-BDC exhibits a high reversible capacity with609/440 m Ah·g^(-1) at 50/2000 m A·g^(-1), and robust cycling stability of 856 m Ah·g^(-1) after 200 cycles at 200 m A·g^(-1),which are obviously superior to that of the Sn Ox/C counterparts. Moreover, an electrochemical reconstruction perspective on the lithium storage mechanism of Sn-BDC is proposed by systematic ex-situ characterizations. The reconstructed SnO_(2) replaces Sn-BDC and becomes the active material in the subsequent cycles. As the by-product of the lithiation reaction, the formed Li-based metal-organic complex(Li-BDC, wrapped around the reconstructed SnO_(2)) plays an important role in alleviating volume expansion and accelerating the charge transfer *** work is beneficial to design and construct the new electrode materials based on the electrochemical reconstruction for advanced LIBs.

关键词： Electrochemical reconstruction Metal-organic complex Anode Lithium storage mechanism Lithium-ion batteries

Organic interfacial engineering of gold nanowires for selective glycerol electrooxidation

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Chinese Chemical Letters 2024年第3期35卷 502-507页

作者： Zhe Wang Qingling hong Boqiang Miao Tianjiao Wang Yu Ding Pujun jin Pei Chen Yu Chen Key Laboratory of Macromolecular Science of Shaanxi Province Key Laboratory of Applied Surface and Colloid Chemistry(Ministry of Education)Shaanxi Key Laboratory for Advanced Energy DevicesSchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an 710062China

The selective electrochemical conversion of glycerol into value-added products is a green and sustainable strategy for the biomass *** this work,Au nanowires(Au-NW)modified with polyethyleneimine(PEI)molecule(Au-NW@PEI)is obtained by an up-bottom post-modification *** characterization,molecular dynamics simulation and density functional theory demonstrate that the loose-packed PEI monolayer firmly and uniformly distribute on the Au-NW surface due to the strong Au-N *** experiments and product analysis display that PEI modification significantly enhance the electro-activity of Au-NW for the glycerol electro-oxidation reaction(GEOR)due to the electronic ***,the steric hindrance and electrostatic effect of PEI layer make the optimizing adsorption of intermediates ***,the selectivity of C3 product glyceric acid over Au-NW@PEI is increased by nearly 20%.The work thus indicates that the rational design of metal-organic interface can effectively elevate the electro-activity and selectivity of Au nanostructures,which may have wide application in biomass development.

关键词： Glycerol electrooxidation reaction Organic interface engineering Gold-based nanomaterials Electrocatalysis Selectivity

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论“新质生产力”的国家方略政策取向

北京工业大学学报（社会科学版） 2024年第2期24卷 1-8页

作者：金碚中国社会科学院工业经济研究所北京100836

生产力是决定经济社会发展的基础性根本性因素,一切经济社会现象归根结底受生产力状况所决定与制约。“新质生产力”是对国家发展方略及政策取向的原则提示,是将国家发展的方略核心,定位于“聚焦生产力,发力新科技”的实践方向;“新质... 详细信息

生产力是决定经济社会发展的基础性根本性因素,一切经济社会现象归根结底受生产力状况所决定与制约。“新质生产力”是对国家发展方略及政策取向的原则提示,是将国家发展的方略核心,定位于“聚焦生产力,发力新科技”的实践方向;“新质生产力”既要有科技创新的要素结构,也要有创新担当和允许试错的制度安排。一个国家的人才政策取向,能否适应更需创新激励与权责担当的就业结构和工作秩序,对经济发展形势具有关键性影响;一心谋发展,聚意高质量,是众望所归的人民意愿,也是国家选择发展模式的政策取向。人类社会随着科技创新,特别是数字化和AI技术的长足发展,重复类工作将被大量替代,新创类工作不断涌现,纠管类工作得以优化。未来由于生产力的质态变化,产业组织也将发生根本性的变革,从而对经济系统中组织资本和信任资本具有更高要求。

关键词：新质生产力国家方略政策取向科技创新

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Application of CFD and FEA Coupling to Predict Structural Dynamic Responses of A Trimaran in Uni-and Bi-Directional Waves

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China Ocean Engineering 2024年第1期38卷 81-92页

作者： LIAO Xi-yu XIA jin-song CHEN Zhan-yang TANG Qin ZHAO Nan ZHAO Wei-dong GUI hong-bin Marine Design&Research Institute of China Shanghai 200011China Ship Structure Division China Ship Scientific Research CenterWuxi 214082China College of Ocean Engineering Harbin Institute of TechnologyWeihaiWeihai 264209China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of TechnologyDalian 116024China School of Foreign Studies Jiangnan UniversityWuxi 214122China

To predict the wave loads of a flexible trimaran in different wave fields,a one-way interaction numerical simulation method is proposed by integrating the fluid solver(Star-CCM+)and structural solver(Abaqus).Differing from the existing coupled CFD-FEA method for monohull ships in head waves,the presented method equates the mass and stiffness of the whole ship to the hull shell so that any transverse and longitudinal section stress of the hull in oblique waves can be ***,verification study and sensitivity analysis are carried out by comparing the trimaran motions using different mesh sizes and time step *** on the wave elevation of uni-and bi-directional waves is also carried *** a comprehensive analysis on the structural responses of the trimaran in different uni-directional regular wave and bi-directional cross sea conditions is carried out,***,the differences in structural response characteristics of trimaran in different wave fields are *** results show that the present method can reduce the computational burden of the two-way fluid-structure interaction simulations.

关键词： CFD-FEA fluid-structure coupling structural responses trimaran bi-directional cross sea

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经济预测的范式变革

经济纵横 2024年第1期 22-27页

作者：金碚中国社会科学院北京100028

现代主流经济学的范式承诺,决定了微观经济学和宏观经济学的“短期分析”和“需求分析”特质。经济预测的性质是以“过去时”数据来推断经济趋势的“未来时”数值,即从“已发生”的现象推测“未发生”的可能。而所选取的统计数据主要包... 详细信息

现代主流经济学的范式承诺,决定了微观经济学和宏观经济学的“短期分析”和“需求分析”特质。经济预测的性质是以“过去时”数据来推断经济趋势的“未来时”数值,即从“已发生”的现象推测“未发生”的可能。而所选取的统计数据主要包括价格类(各种价格指数)、增长性(GDP等)和货币量(财政、金融、信贷)。基于宏观经济学方法的经济预测,以短期分析为要才更有把握。但是,从经济预测和展望的更大价值来看,仅仅局限于短期预测显然是不能令人满意的,其价值也有限。所以,经济学家总是希望并努力进入长期性(中长期)分析领域。短期经济预测的关切目标以经济理性(工具理性)主导,比较专一,尤其是集中于对经济增长率的特别关注和工具性意义。而对于长期经济展望,关切目标则更倾向于以本真理性(直接福利)主导,具有多目标特征,追求更全面的经济发展成效,由对“高速度增长”的专一关注转向对“高质量发展”的全面关注。当经济学家从短期“经济预测”向长期“经济展望”延伸时,就面临一个不可回避的挑战——经济学的范式变革。为此,对统计数据和统计方法也会提出更多新的要求。对传统主流经济学进行范式变革是经济学进步的必然。其基本趋向是,从“微观—宏观”的唯一以工具理性为分析维度的范式,转向以理性、文化、制度三维度为分析范式。

关键词：短期经济预测长期经济展望经济学范式结构变化

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新型工业化时期老龄产业的地位和机理

北京工业大学学报（社会科学版） 2024年第4期24卷 1-11页

作者：金碚中国社会科学院工业经济研究所北京100836

老龄化是人类文明进入发达形态的标志性现象,当观察和研究老龄化现象和老龄社会时,经济学的范式承诺就必须从“经济人”假设转变为结构性人口假设,每个国家都必须以新的思维和行为方式来安排全社会的生存模式。随着社会生产力的显著进步... 详细信息

老龄化是人类文明进入发达形态的标志性现象,当观察和研究老龄化现象和老龄社会时,经济学的范式承诺就必须从“经济人”假设转变为结构性人口假设,每个国家都必须以新的思维和行为方式来安排全社会的生存模式。随着社会生产力的显著进步,人口受教育程度的提高,老龄人口发挥“活力”的需要也日趋增强;工业机器人技术可以为老龄智能机器人发展提供多方面的技术供应和创新借鉴,最大限度减少失能老人的无助和增强老人老龄产业的经济学效应,不仅体现在赋能助能老龄人口,使其活力化,而且体现在可以激发产业发展的供给侧创新和需求侧拉动,形成老龄产品市场供求结构的新格局。健康的自益性、公益性和公论性特质在老龄化国家和老龄社会受到社会各方的高度重视,大量经济资源和技术创新能力必然会流向老龄产业,在新型工业化时代,企业界更普遍地具有社会责任意识和行为特征,社会企业的发展空间也更为宽广,并具有很大的社会期望迫切性;老龄产业的发展将获得更大机会的空间拓展和形态完善,承担特殊的经济发展使命,成为新型工业化时代极具人本关怀特质的标志性产业之一。

关键词：老龄产业老龄社会老龄智能机器人,老龄人口活力化社会企业责任

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Clinical significance of preoperative nutritional status in elderly gastric cancer patients undergoing radical gastrectomy:A singlecenter retrospective study

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2211-2220页

作者： Xi-Ning Zhao jing Lu hong-Yong He Sheng-jin Ge Department of Anesthesiology Zhongshan HospitalFudan UniversityShanghai 200032China Department of Nursing Zhongshan HospitalFudan UniversityShanghai 200032China Department of General Surgery/Emergency Surgery Zhongshan HospitalFudan UniversityShanghai 200032China

BACKGROUND The population of elderly patients with gastric cancer is increasing,which is a major public health issue in *** is one of the greatest risk factors for adverse clinical outcomes in elderly patients with gastric *** To investigate the preoperative nutritional status and its association with delayed discharge of elderly gastric cancer patients following radical *** A total of 783 patients aged 65 years and older harboring gastric adenocarcinoma and following radical gastrectomy were retrospectively analyzed from the prospectively collected database of Zhongshan Hospital of Fudan University between January 2018 and May *** The overall rate of malnutrition was 31.8%.The incidence of postoperative complications was significantly higher in the malnourished group compared to the well-nourished group(P<0.001).Nutritional characteristics in the malnourished group,including body mass index,prognostic nutritional index(PNI),albumin,prealbumin,and hemoglobin,were all significantly lower than those in the well-nourished *** percentage of patients who received postoperative total nutrient admixture was lower in the malnourished group compared to the wellnourished group(22.1%vs 33.5%,P=0.001).Age≥70 years(HR=1.216,95%CI:1.048-1.411),PNI<44.5(HR=1.792,95%CI:1.058-3.032),operation time≥160 minutes(HR=1.431,95%CI:1.237-1.656),and postoperative complications grade III or higher(HR=2.191,95%CI:1.604-2.991)were all recognized as independent risk factors associated with delayed *** Malnutrition is relatively common in elderly patients undergoing *** PNI is an independent risk factor associated with delay *** strategies are needed to improve the clinical outcome of these patients.

关键词： Gastric cancer Preoperative nutritional status Malnutrition Elderly Radical gastrectomy

Antimony doped CsPbI_(2)Br for high-stability all-inorganic perovskite solar cells

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Nano Research 2024年第3期17卷 1508-1515页

作者： Mengfei Zhu Lina Qin Yuren Xia Junchuan Liang Yaoda Wang Daocheng hong Yuxi Tian Zuoxiu Tie Zhong jin State Key Laboratory of Coordination Chemistry Ministry of Education(MOE)Key Laboratory of Mesoscopic ChemistryMOE Key Laboratory of High Performance Polymer Materials and TechnologyJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Nanjing Tieming Energy Technology Co. Ltd.Nanjing 210093China Suzhou Tierui New Energy Technology Co. Ltd.Suzhou 215228China

All-inorganic perovskites,adopting cesium(Cs+)cation to completely replace the organic component of A-sites of hybrid organic–inorganic halide perovskites,have attracted much attention owing to the excellent thermal ***,all-inorganic iodine-based perovskites generally exhibit poor phase stability in ambient ***,we propose an efficient strategy to introduce antimony(Sb^(3+))into the crystalline lattices of CsPbI_(2)Br perovskite,which can effectively regulate the growth of perovskite crystals to obtain a more stable perovskite *** to the much smaller ionic radius and lower electronegativity of trivalent Sb^(3+)than those of Pb^(2+),the Sb^(3+)doping can decrease surface defects and suppress charge recombination,resulting in longer carrier lifetime and negligible *** a result,the all-inorganic perovskite solar cells(PSCs)based on 0.25%Sb^(3+)doped CsPbI_(2)Br light absorber and screen-printable nanocarbon counter electrode achieved a power conversion efficiency of 11.06%,which is 16%higher than that of the control devices without Sb^(3+)***,the Sb^(3+)doped all-inorganic PSCs also exhibited greatly improved endurance against heat and *** to the use of low-cost and easy-to-process nanocarbon counter electrodes,the manufacturing process of the all-inorganic PSCs is very convenient and highly repeatable,and the manufacturing cost can be greatly *** work offers a promising approach to constructing high-stability all-inorganic PSCs by introducing appropriate lattice doping.

关键词： all-inorganic perovskite solar cells Sb doped cesium lead halide perovskites foreign B-site ions hole-conductor-free phase stability improvement