Full-Scale Isogeometric Topology Optimization of Cellular Structures Based on Kirchhoff-Love Shells

Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight ratio.In this paper,a full-scale isogeometric topology optimization(ITO)method based on Kirchhoff-Love shells for designing cellular tshin-shell structures with excellent damage tolerance ability is proposed.This method utilizes high-order continuous nonuniform rational B-splines(NURBS)as basis functions for Kirchhoff-Love shell elements.The geometric and analysis models of thin shells are unified by isogeometric analysis(IGA)to avoid geometric approximation error and improve computational accuracy.The topological configurations of thin-shell structures are described by constructing the effective density field on the controlmesh.Local volume constraints are imposed in the proximity of each control point to obtain bone-like cellular structures.To facilitate numerical implementation,the p-norm function is used to aggregate local volume constraints into an equivalent global constraint.Several numerical examples are provided to demonstrate the effectiveness of the proposed method.After simulation and comparative analysis,the results indicate that the cellular thin-shell structures optimized by the proposed method exhibit great load-carrying behavior and high damage robustness.

Deciphering the potential mechanism of Radix Rehmanniae Praeparata for treating cancer-related anemia based on network pharmacology and molecular docking technology

Background:Rehmanniae Radix Praeparata(RRP,Shu Dihuang in Cinese)is a traditional Chinese herb with multiple pharmacological effects and is commonly used to treat blood deficiency syndrome,such as cancer-related anemia(CRA),alone or in combination with other herbs.However,its main active ingredients and mechanisms of action in treating CRA remain unknown.This study aims to elucidate RRP’s potential mechanism and main active components in treating CRA by using network pharmacology and molecular docking technology system.Methods:The main components of RRP were obtained by the TCMSP database and literature search,and active components and potential targets were obtained by the SwissADME and SwissTargetPridiction databases.CRA targets were collected through GeneCards,DisGeNET,and DrugBank databases.Protein-protein interaction networks of potential targets were constructed via STRING 11.5 and analyzed visually with Cytoscape 3.9.1.The Metascape platform was used for Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis,which were subsequently visualized with Cytoscape 3.9.1 or SangerBox platform.Moreover,Autodock Vina was used for the molecular docking of potential targets and main active ingredients that were visualized with PyMOL software.Results:In this study,31 main active ingredients of PPR were screened,and 155 related targets related to CRA were unearthed.Protein-protein interaction results showed that PPR’s core proteins for CRA intervention correlate to STAT3,SRC,MAPK3,MAPK1,PIK3R1,PIK3CA,and AKT.Multiple signaling pathways were closely related to the treatment of CRA intervened by PPR,including the PI3K-Akt signaling pathway,HIF-1 signaling pathway,JAK-STAT3 signaling pathway,TNF-αsignaling,cytokine signaling pathway and NF-kappB signaling pathway,which are closely involved in the proliferation and differentiation of hematopoietic stem cell and inflammatory response.Molecular docking results showed that these potential targets had good conformation with the core active components of RRP for treating CRA.Conclusion:This study revealed RRP’s main active components and potential molecular mechanisms in treating CRA,providing a reference for subsequent basic research.

水-沉积物界面重金属迁移转化影响因素研究进展

水-沉积物界面是重金属发生迁移转化的主要场所,环境中各种因素可对其过程产生影响,为探讨这些因素对重金属在水-沉积物界面迁移转化过程的影响,围绕沉积物周围的潜在因素进行全面分析,选择上覆水环境因子(pH值、氧化还原条件、离子强度和温度)、重金属赋存形态和沉积物颗粒大、小分别对重金属迁移转化的影响进行分析,探讨上述各因素对重金属迁移转化的影响机理机制过程,最后对重金属迁移转化方面的研究进行归纳总结和未来展望。

水体溶解性有机质与重金属影响机理的研究进展

溶解性有机质(DOM)是水体中最活跃的组分,可与金属离子发生吸附、络合、氧化还原等一系列反应,影响金属离子在水环境中的迁移转化。DOM的主要成分为腐殖质,而富里酸(FA)和胡敏酸(HA)为腐殖质中占比最高的2种成分,占DOM总量的40%~60%。DOM与重金属离子的相互作用一般用稳定常数表示其形成的络合物的稳定性,对重金属离子的吸附量和吸附率会受到pH值、温度、反应时间等多种环境因素的影响。在调研大量国内外文献基础上,综述了DOM与重金属离子相互作用机制及其影响的研究进展。

自然水体沉积物污染类型及风险评价研究进展

自然水体沉积物是污染物的主要富集地,探究沉积物类型并对污染情况作出评价,是了解自然水体沉积物污染状况的有效手段,可为有关部门进行风险管理与决策提供依据。本文分析了我国自然水体沉积物中的氮磷营养盐、重金属和毒害性有机污染物以及其风险评价方法,并对国内外常用的风险评价方法进行对比分析。分析发现我国自然水体沉积物风险评价标准还不够完善,主要体现在沉积物质量基准研究和污染物毒性风险评价上,多种污染物缺少统一的质量标准和毒害因子。

Meter-Scale Thin-Walled Structure with Lattice Infill for Fuel Tank Supporting Component of Satellite:Multiscale Design and Experimental Verification

Lightweight thin-walled structures with lattice infill are widely desired in satellite for their high stiffness-to-weight ratio and superior buckling strength resulting fromthe sandwich effect.Such structures can be fabricated bymetallic additive manufacturing technique,such as selective laser melting(SLM).However,the maximum dimensions of actual structures are usually in a sub-meter scale,which results in restrictions on their appliance in aerospace and other fields.In this work,a meter-scale thin-walled structure with lattice infill is designed for the fuel tank supporting component of the satellite by integrating a self-supporting lattice into the thickness optimization of the thin-wall.The designed structure is fabricated by SLM of AlSi10Mg and cold metal transfer welding technique.Quasi-static mechanical tests and vibration tests are both conducted to verify the mechanical strength of the designed large-scale lattice thin-walled structure.The experimental results indicate that themeter-scale thin-walled structure with lattice infill could meet the dimension and lightweight requirements of most spacecrafts.

A Comprehensive Review of Isogeometric Topology Optimization:Methods,Applications and Prospects

Topology Optimization(TO)is a powerful numerical technique to determine the optimal material layout in a design domain,which has accepted considerable developments in recent years.The classic Finite Element Method(FEM)is applied to compute the unknown structural responses in TO.However,several numerical deficiencies of the FEM significantly influence the effectiveness and efficiency of TO.In order to eliminate the negative influence of the FEM on TO,IsoGeometric Analysis(IGA)has become a promising alternative due to its unique feature that the Computer-Aided Design(CAD)model and Computer-Aided Engineering(CAE)model can be unified into a same mathematical model.In the paper,the main intention is to provide a comprehensive overview for the developments of Isogeometric Topology Optimization(ITO)in methods and applications.Finally,some prospects for the developments of ITO in the future are also presented.

A Comprehensive Approach for the Clustering of Similar-Performance Cells for the Design of a Lithium-Ion Battery Module for Electric Vehicles

An energy-storage system comprised of lithium-ion battery modules is considered to be a core component of new energy vehicles,as it provides the main power source for the transmission system.However,manufacturing defects in battery modules lead to variations in performance among the cells used in series or parallel configuration.This variation results in incomplete charge and discharge of batteries and non-uniform temperature distribution,which further lead to reduction of cycle life and battery capacity over time.To solve this problem,this work uses experimental and numerical methods to conduct a comprehensive investigation on the clustering of battery cells with similar performance in order to produce a battery module with improved electrochemical performance.Experiments were first performed by dismantling battery modules for the measurement of performance parameters.The kmeans clustering and support vector clustering(SVC)algorithms were then employed to produce battery modules composed of 12 cells each.Experimental verification of the results obtained from the clustering analysis was performed by measuring the temperature rise in the cells over a certain period,while air cooling was provided.It was found that the SVC-clustered battery module in Category 3 exhibited the best performance,with a maximum observed temperature of 32℃.By contrast,the maximum observed temperatures of the other battery modules were higher,at 40℃for Category 1(manufacturer),36℃for Category 2(manufacturer),and 35℃for Category 4(k-means-clustered battery module).

陆浑水库滨岸带沉积物重金属污染评价及其迁移能力分析

为研究滨岸带沉积物重金属污染及迁移转化情况,以陆浑水库滨岸带为研究对象,采用地累积指数法和潜在生态风险评价法对重金属的污染程度及风险进行评价,并采用重金属活力值法评价重金属的迁移能力。结果显示:重金属Cu、Pb、Cd、Cr、Mo、Zn的含量均超出了土壤环境背景值,分别为背景值的2.88、2.61、21.54、2.02、78.87、1.19倍;各采样带中的重金属含量随海拔高度的变化而变化,其中,Cr、Zn、Cd、Pb和Mo的含量自L4采样带起随海拔的降低而逐渐下降;Mo存在严重超标现象,属于Mo极重度污染,Cd为中度、偏重度污染;陆浑水库滨岸带整体处于极强的污染状态,Mo和Cd是生态风险的主要贡献因子,各重金属的污染风险程度与地累积指数法的结果相符合;根据活力值法显示各重金属迁移能力由强到弱的顺序为:Cd>Pb>Mo>Cu>Zn≈Cr。

从计算机辅助设计(CAD)到人辅助设计(HAD)--一种等几何拓扑优化方法

本文提出了一种新的设计模式——人辅助设计,以取代传统的计算机辅助设计。在人辅助设计中,计算机可以通过一种新的等几何拓扑优化自动完成整个产品设计,而人类仅需协助轻微修改设计以满足要求。文中提出了一种嵌入域等几何拓扑优化用于设计具有不规则设计域的复杂模型,并且可以基于分层等几何拓扑优化结果自动生成优化结果的可编辑几何模型。测试了三个算例以验证所提出的等几何拓扑优化模式,包括一个具有规则设计域的3D悬臂梁,一个具有不规则设计域的汽车零件和一个具有多尺度结构的MBB梁。结果表明,所提出的等几何拓扑优化模式可以自动生成高质量的优化模型。因此,该技术具有成为革命性技术的巨大潜力,将当前设计模式由计算机辅助设计转变为人辅助设计。

Primary repair of esophageal atresia gross type C via thoracoscopic magnetic compression anastomosis:A case report

BACKGROUND Esophageal atresia(EA)is a life-threatening congenital malformation in newborns,and the traditional repair approaches pose technical challenges and are extremely invasive.Therefore,surgeons have been actively investigating new minimally invasive techniques to address this issue.Magnetic compression anastomosis has been reported in several studies for its potential in repairing EA.In this paper,the primary repair of EA with magnetic compression anastomosis under thoracoscopy was reported.CASE SUMMARY A full-term male weighing 3500 g was diagnosed with EA gross type C.The magnetic devices used in this procedure consisted of two magnetic rings and several catheters.Tracheoesophageal fistula ligation and two purse strings were performed.The magnetic compression anastomosis was then completed thoracoscopically.After the primary repair,no additional operation was conducted.A patent anastomosis was observed on the 15th day postoperatively,and the magnets were removed on the 23rd day.No leakage existed when the transoral feeding started.CONCLUSION Thoracoscopic magnetic compression anastomosis may be a promising minimally invasive approach for repairing EA.

东北刺人参抗疲劳及改善睡眠节律作用研究

目的:探讨东北刺人参根水提取物冻干粉的抗疲劳和改善睡眠节律的作用。方法:在小鼠力竭游泳实验中,将小鼠随机分为空白对照组、东北刺人参低剂量组(125 mg/kg)、中剂量组(250 mg/kg)、高剂量组(500 mg/kg)连续灌胃给药15 d,检测血清中尿素氮(BUN)和乳酸脱氢酶(LDH)水平,以及肝组织中谷胱甘肽过氧化物酶(GSH-Px)和三磷酸腺苷酶(ATPase)活力等指标。同时采用果蝇活动监测系统(DAMS),以果蝇为观察对象,以睡眠时间和睡眠-觉醒节律为考察指标,分别考察东北刺人参对果蝇睡眠的干预作用。结果:东北刺人参能延长小鼠负重游泳时间,高中低剂量组延长率分别为126.16%、102.44%和62.32%,亦可提高自由泳小鼠GSH-Px、LDH和ATPase活性,降低BUN水平。对果蝇睡眠节律影响实验结果显示,东北刺人参可以增加雄果蝇平均睡眠时间,减少自主活动次数,且呈现剂量依赖性。同时,减少雌果蝇自主活动次数,缩短白天活动时间,缩短片段化睡眠,增加夜晚睡眠时间,且明显后移睡眠相位角。结论:东北刺人参能显著增加果蝇的睡眠时间,改善睡眠节律,可加速疲劳的消除,并可以延长小鼠力竭游泳时间,提高其运动耐力,减少自由基的堆积,加快体内代谢产物的清除,延缓疲劳的产生。

±1100 kV吉泉线雷击致灾因子权重分析及高风险杆塔筛选

目前已知输电线路雷击致灾因子主要包括雷电参数、地形地貌、绝缘配置、接地电阻等,但针对某条特定的线路,无法获得各因子对雷击风险的权重占比。以±1100 kV吉泉线为研究对象,深入挖掘该线路的雷击致灾因子,利用雷电灾害风险评估层次分析法,通过计算隶属度、构建判断矩阵对各致灾因子的权重占比进行分析。研究结果表明,该线路的沿线走廊地闪密度、雷电流幅值、边导线保护角的权重分别为0.420、0.247、0.147,是雷击风险权重较大的致灾因子。根据权重较高的致灾因子,采用分析集合的方法,筛选出了雷击闪络风险较高杆塔,为该线路防雷治理提供了重要依据。此方法比起逐基杆塔差异化防雷评估,可快速筛选出雷击闪络风险等级较高杆塔,显著降低工作烦冗度,适用于里程较长线路及批量线路雷害风险评估。

不同来源灵芝孢子粉多指标质量评价

目的以多糖、三萜及甾醇、重金属元素含量为指标评价不同来源灵芝孢子粉质量。方法采用紫外-可见分光光度法及电感耦合等离子体质谱(ICP-MS)分别测定多糖、三萜及甾醇、重金属元素含量。分析不同树种及采收期灵芝孢子粉的含量差异规律。结果桦树样品及八月上旬采收样品中多糖含量较高,桑树样品及九月中下旬采收的样品中三萜及甾醇含量较高,不同树种及采收期样品重金属含量均符合限量要求。结论灵芝孢子粉可考虑采用桑树或白杨树树种进行栽培,于九月中下旬采收。

开创新时代社会治理新格局

我国社会治理,基本遵循了从"社会管理"到"共建共治共享"跨越的创新逻辑,但在现实中,治理"瓶颈"仍然存在,主要表现为治理结构没有跟上实践发展、治理主体关系没有及时法定化、治理过程不够协调、治理规范不够完善。党的十九大以来,我国社会治理将在体系、机制、制度等三个方面并进,规范多元主体参与的共建体系、创新化解社会矛盾的共治机制,完善民生获得的共享制度,从而开创新时代社会治理新格局。

巴西海木提取物抗生殖系统氧化损伤活性研究

目的考察巴西海木提取物对生殖系统氧化损伤的影响,初步探究其作用机制。方法采用水和不同比例(50%、70%及95%)乙醇溶液浸提巴西海木树皮,得到4种粗提物;依次用石油醚、乙酸乙酯和正丁醇萃取不同比例醇提物,得到9种有机相组分,共得到13种巴西海木提取物TCE-1~TCE-13。以小鼠睾丸支持细胞(TM4)增殖率变化为指标考察各提取物的细胞毒作用;采用H_(2)O_(2)处理TM4细胞建立氧化损伤模型,以细胞存活率及氧化指标超氧化物歧化酶(SOD)活力、丙二醛(MDA)含量和谷胱甘肽过氧化物酶(GSH-Px)活力变化为指标,邻苯二甲酸二(2-乙基己基)酯(DEHP)处理雄性小鼠建立生殖系统氧化损伤模型,造模后灌胃给予300、600、900 mg·kg^(-1)50%粗提乙酸乙酯组分(TCE-6)28 d后,以睾丸组织氧化指标变化验证TCE-6药效。最后通过实时荧光定量PCR(qRT-PCR)检测相关基因的表达情况,初步探究其作用机制。结果细胞毒性实验结果表明95%粗提物(TCE-4),50%粗提石油醚组分(TCE-5)、正丁醇组分(TCE-7),70%粗提石油醚组分(TCE-8)、正丁醇组分(TCE-10)以及95%粗提石油醚(TCE-11)、正丁醇组分(TCE-13)对TM4细胞具有杀伤作用。50%粗提物(TCE-2)、TCE-6以及70%粗提乙酸乙酯组分(TCE-9)给药组显著提高氧化损伤后TM4细胞存活率,TCE-6组SOD、GSH-Px活力显著提高、MDA含量显著下降(P<0.01)。900 mg·kg^(-1)TCE-6处理后能显著提高氧化损伤模型小鼠睾丸组织内SOD、GSH-Px活力,降低MDA含量(P<0.05)。qRT-PCR结果表明,900 mg·kg^(-1)TCE-6处理后提高了核因子E2相关因子2(Nrf2)、超氧化物歧化酶2(SOD2)及超氧化物歧化酶3(SOD3)mRNA的表达(P<0.05)。结论TCE-6可能通过上调SOD酶家族表达和调节Nrf2信号通路发挥抗生殖系统氧化损伤作用,具有开发为生殖系统损伤治疗药物的潜力。

Construction of Desirable NiCoTe_(2) Nanosheet Arrays on a Carbon Cloth Substrate as a Positive Electrode Material for a High-Performance Asymmetric Supercapacitor

Nickel–cobalt tellurides are deemed as promising electrode materials for energy storage devices due to their superior conductivity and theoretical specific capacitance.Here,NiCoTe_(2)was successfully fabricated on carbon cloth by facile electrodeposition and hydrothermal synthesis,which can directly serve as a binderless electrode.The NiCoTe_(2)with interconnected nanosheet arrays on a conductive carbon substrate showed a high specific capacitance(924 F/g at 1 A/g)and robust longterm cycling stability(89.6%retention after 5000 cycles).In addition,the assembled NiCoTe_(2)//activiated carbon hybrid supercapacitor achieved a high energy and power density with a short charging time(42.26 Wh/kg at a power density of 760.96 W/kg).This work provides a novel idea to produce bimetallic nickel–cobalt telluride nanosheet array electrodes for high-performance hybrid supercapacitors.

One-Step Hydrothermal Synthesis of a CoTe@rGO Electrode Material for Supercapacitors

CoTe@reduced graphene oxide(CoTe@rGO)electrode materials for supercapacitors were prepared by a one-step hydrothermal method in this paper.Compared with that of pure CoTe,the electrochemical performance of CoTe@rGO was significantly improved.The results showed that the optimal CoTe@rGO electrode material has a remarkably high specific capacitance of 810.6 F/g at a current density of 1 A/g.At 5 A/g,the synthesized material retained 77.2%of its initial capacitance even after 5000 charge/discharge cycles,thereby demonstrating good cycling stability.Moreover,even at a high current density of 20 A/g,the composite electrode retained 79.0%of its specific capacitance at 1 A/g,thus confirming its excellent rate performance.An asymmetric supercapacitor(ASC)with a wider potential window and higher energy density was assembled by using 3 M KOH as the electrolyte,the CoTe@rGO electrode as the positive electrode,and active carbon as the negative electrode.The operating voltage of the supercapacitor could be increased to 1.6 V,and its specific capacitance could reach 112.6 F/g at 1 A/g.The specific capacitance retention rate of the fabricated supercapacitor after 5000 charge/discharge cycles at 5 A/g was 87.1%,which confirms its excellent cycling stability.In addition,the ASC revealed a high energy density of 40.04 W·h/kg at a power density of 799.91 W/kg and a high power density of 4004.93 W/kg at an energy density of 33.43 W·h/kg.These results collectively show that CoTe@rGO materials have broad application prospects.

基于物联网技术的铁路车站能源源点动态监测系统设计

随着铁路建设的快速发展,运营里程不断增加,导致能源需求不断加大,铁路企业节能减排的重要性凸显,而物联网技术的研究与应用是铁路实现节能减排的重要手段之一。阐述基于物联网技术的车站能源源点动态监测系统的目标、要求和总体架构,以及基础管理、分区管理、远程管理、展示应用、预警推送、用能报表和统计分析等主要功能,并对预期效果进行分析。

替莫唑胺原料药粒度测定方法研究

采用Malvern Mastersizer 2000型激光粒度分析仪研究微粉化替莫唑胺粒度测定方法。通过筛选分散剂种类、表面活性剂及其浓度,设定仪器参数,筛选样品浓度及进行溶液稳定性研究确定了一种全新的替莫唑胺粒度测定方法。方法的精密度和耐用性验证结果表明本文确定的方法精密度及耐用性好。本法可准确测定微粉化替莫唑胺原料药的粒度。