Superfast and solvent-free core-shell assembly of sulfur/carbon active particles by hail-inspired nanostorm technology for high-energy-density Li-S batteries

The demand on low-carbon emission fabrication technologies for energy storage materials is increasing dramatically with the global interest on carbon neutrality.As a promising active material for metal-sulfur batteries,sulfur is of great interest due to its high-energy-density and abundance.However,there is a lack of industry-friendly and low-carbon fabrication strategies for high-performance sulfur-based active particles,which,however,is in critical need by their practical success.Herein,based on a hail-inspired sulfur nano-storm(HSN)technology developed in our lab,we report an energy-saving,solvent-free strategy for producing core-shell sulfur/carbon electrode particles(CNT@AC-S)in minutes.The fabrication of the CNT@AC-S electrode particles only involves low-cost sulfur blocks,commercial carbon nanotubes(CNT)and activated carbon(AC)micro-particles with high specific surface area.Based on the above core-shell CNT@AC-S particles,sulfur cathode with a high sulfur-loading of 9.2 mg cm^(-2) delivers a stable area capacity of 6.6 mAh cm^(-2) over 100 cycles.Furthermore,even for sulfur cathode with a super-high sulfur content(72 wt%over the whole electrode),it still delivers a high area capacity of 9 mAh cm^(-2) over50 cycles in a quasi-lean electrolyte condition.In a nutshell,this study brings a green and industryfriendly fabrication strategy for cost-effective production of rationally designed S-rich electrode particles.

Analysis of Soundproof Technology of Assembled Steel Structure Houses

The problem of noise has always been highlighted in assembled steel structure houses.Therefore,it is necessary to use effective soundproof measures where steel beams intersect with the reserved line pipe openings,doors,windows,elevator shafts,and other locations.In this paper,we will investigate the areas with subpar soundproof performance in an assembled steel structure residential project and propose suitable noise control measures to address this issue.

Application of Prefabrication and Assembly to Hong Kong-Zhuhai- Macao Bridge

The Hong Kong-Zhuhai-Macao Bridge(HZMB)project,which has just been opened to traffic in 2018.The special location,construction conditions,quality requirements and multiple functions of HZMB brought many challenges,such as management,technology,safety and environmental protection.To meet these challenges and ensure the achievement of high quality and 120 years design service life,the HZMB project first introduced the completely new concept of"Large size,Factory production,Standardization and Assembly",which was fundamental to the design and construction.This was developed in consideration of the difficulties of the offshore environment.The core idea was Prefabrication and Assembly,which was to change this HZMB project into onshore work as much as possible by cutting this mega sea-crossing into large sized components,which could be prefabricated on land and then transported to the offshore site for assembly.The success of the HZMB undoubtedly has led the technology of prefabrication and assembly to a new height and recognized scale.This paper describes the implementation process of the concept;"Large size,Factory production,Standardization and Assembly"(LFSA)to the HZMB.

Overview of Key Technologies and On-orbit Verification of China Space Station

Tiangong space station is a space station independently designed and developed by China.In order to build and operate the space station,it was necessary to make breakthroughs in many fields and master several key technologies,which were characterized over a long technological span and underwent difficult verifications.Therefore,in addition to ground verification,on-orbit flight tests of key technologies for the assembly,construction and operation of the space station were planned to be conducted used by the core module,taking into account the differences in the gravity environment between space and the Earth,in order to lay a foundation for the subsequent comprehensive assembly,construction and long-term on-orbit operation of the space station.In this paper,the mission characteristics of the space station are briefly introduced,along with the key technologies for the assembly and construction of the space station,and then the on-orbit verification tests are comprehensively introduced.

Key Technology and Complete-set Equipment for Intelligent Construction of HSR Simply-supported Girder Reinforcement Framework

In view of the problems such as backward production mode,poor quality stability,high safety risk and incomplete control system during erection of the reinforcement framework of simply-supported box girders for high-speed railway(HSR),and in combination with the key points and main challenges in the reinforcement framework construction of Guangzhou-Zhanjiang HSR,the overall technical route for the intelligent manufacturing of reinforcement framework of simply-supported box girders is put forward.The component design of reinforcement framework of simply supported box girder is carried out based on BIM,and the feasibility of the scheme is verified through segment assembly test.The assembly techniques are studied in combination with the mesh design scheme to achieve rapid forming of the reinforcement framework.R&D of automatic processing equipment for components,material transshipment equipment,automatic hoisting equipment and technological equipment for assembly clamping fixture are carried out to realize the overall design of equipment production line.An intelligent control system is developed for the whole-process intelligent construction of reinforcement framework to realize the full life-cycle applications for the workshop production and visual management including intelligent layout and quality traceability.The research results systematically optimize and innovate the assembly and forming technologies of reinforcement framework in the prefabrication beam yard of high-speed railway,realize the component processing,automatic assembly and information technology management,improve the construction quality,efficiency and information technology level of intelligent manufacturing of reinforcement framework of railway prefabricated beam as a whole,and reduce the construction cost of the project.The research has realized a major breakthrough in the construction technology of railway prefabricated box girders,which has the extensive technical and market promotion values.

狭小复杂场地大型钢结构施工关键技术

苏州国际大酒店项目施工场地狭小复杂,利用在地下室结构顶板上开辟材料运输通道、吊装平台,提高结构施工效率,解决土建施工和钢结构施工时场地冲突问题。钢结构施工组织采用了多种形式吊装关键技术,不仅保证了土建施工和钢结构施工组织最优化,而且保证了工期,提高了工程质量和施工安全性。

Thruster direction controlling of assembled spacecraft based on gimbal suspension

The attitude control system design and its control effect are affected considerably by the mass-property parameters of the spacecraft. In the mission of on-orbit servicing, as fuel is expended, or the payloads are added or removed, the center of mass will be changed in certain axe; consequently, some thrusters＇ directions are deviated from the center of mass（CM） in certain plane. The CM of assembled spacecraft estimation and thruster direction control are studied. Firstly, the attitude dynamics of the assembled spacecraft is established based on the Newton-Euler method. Secondly, the estimation can be identified by the least recursive squares algorithm. Then, a scheme to control the thrusters＇ directions is proposed. By using the gimbal installed at the end of the boom, the angle of the thruster is controlled by driving the gimbal; therefore, thrusters can be directed to the CM again. Finally, numerical simulations are used to verify this scheme. Results of the numerical simulations clearly show that this control scheme is rational and feasible.

基于翻转课堂的生物信息应用工具普及——以生物化学教学为例

生物化学的研究对象的复杂性和研究手段的多样性,决定其教学的面广、概念多、难度大。因此,新的教学改革与创新势在必行。翻转课堂是指重新调整课堂内外的时间,将学习的决定权从教师转移给学生。该文的教学团队引导学生在翻转课堂教学环节中普及生物信息学工具,并以“生化集结号”为教学活动主题,在教学实践中对于该模式进行一系列教学改革探索。

VR技术在船舶分段装配实训教学中的应用

VR技术与传统教学的融合是现阶段教育教学的一个发展趋势。基于当前VR技术在实训教学中的现状,探讨VR技术在船舶分段装配仿真实训教学中的作用和意义,并具体分析了VR技术在船舶分段装配实训教学中的应用。通过调查分析证明了VR技术在船舶分段装配仿真实训教学中的应用效果,最后提出推进VR技术在船舶分段装配仿真实训教学中的具体操作建议。

大中型液体运载火箭水平起竖与发射技术

未来大量中低轨商业卫星的发射任务对大中型运载火箭提出了快速测发的技术需求。地面发射支持系统针对CZ-8火箭需求,在传统运载型号已有技术的基础上,重点开展了箭体整体水平组装及起竖对接技术、快速智能测发技术的研究,旨在进一步提升火箭发射任务效率、简化发射场设施、降低发射成本。以箭体水平组装设备、整体转运起竖对接设备、智能供气系统为切入点,对相关技术进行了阐述,此外,还提出了吊具、支架车两种水平组装方案。对整体转运起竖对接精度影响因素进行了分析,并介绍了起竖托架的刚度提升方法。介绍了智能供配气总体方案、智能减压阀技术、供配气设备故障诊断技术。

预制装配式地铁车站施工技术与造价控制分析

概述了预制装配式地铁车站预制构件的设计标准、结构设计与功能布局,以及预制与现场装配的接口设计;分析了预制装配式地铁车站的施工技术,涵盖施工前的准备工作、预制构件的制造、现场装配技术、安全与质量管理,以及特殊条件下的施工策略;讨论了预制装配式地铁车站的成本分析、材料选择与采购、施工过程中的成本管理,以及长期运维成本的考虑。

新型预制节段拼装桥墩抗震性能及塑性铰区变形分析

为探究采用两种不同连接方式(Fiber Reinforced Concrete(FRC)+锥套锁紧纵筋和Ultra-High Performance Concrete(UHPC)+纵筋错位搭接)预制节段拼装桥墩塑性铰性能,设计并制作了4组大比例缩尺(1∶2.5)桥墩。通过拟静力试验,采用数字图像相关(Digital Image Correlation,DIC)技术得到应变场和位移场,利用应变场和位移场捕捉并计算4个桥墩试件塑性铰区的裂缝发展趋势和宽度。结果表明:在大比例尺试件上,采用DIC技术测量位移具有较高的可靠性。4个桥墩试件加载至中高水平荷载时塑性铰区位移呈现非线性变化,具有明显的塑性位移发展趋势;两种连接方式接缝处裂缝宽度约为其他部位的2~8倍,表明接缝处为预制节段拼装桥墩变形的主要集中区域。

农用挖掘机卷筒虚拟装配规划设计与研究--基于CAM技术

首先,采用CAD软件对农用挖掘机卷筒结构进行了设计;然后,对结构的受力情况进行了分析;最后,基于CAM和VR技术实现了对农用挖掘机卷筒装配规划的设计与应用。仿真实验验证了此方法具有可行性,可对装配过程实现优化,大大提高设计效率。

基于虚拟仿真技术的收割机零部件智能化装配研究

为准确实现收割机零部件智能化装配,并获取最佳收割机零部件智能化装配路径,该文设计了基于虚拟仿真技术的收割机零部件智能化装配方法。首先采用Pro/E软件构建收割机零部件三维模型;然后构建收割机零部件智能化装配结构树模型反映收割机与零部件间的父子关联特性,并设计零部件装配约束条件,以约束条件完成收割机零部件智能化装配;最后利用遗传蚁群算法获取收割机零部件智能化装配规划的最佳路径。实验表明,该方法既可实现收割机零部件智能化装配,又可计算出收割机零部件智能化装配规划的最佳路径,提升收割机的智能化装配速度。

基于BIM技术的小型装配式建筑在乡村民居中的应用前景

随着国家“双碳”战略目标和美丽乡村建设的不断推进,乡村民居的更新改造及建设逐年增加,但普遍存在着建筑质量差、缺乏规范设计、抗震性能差、布局不合理、存在安全隐患、不节能环保、功能不完善等问题。为打造高质量的乡村民居,以大理白族乡村民居为例,通过对目前乡村民居更新改造现状和存在的主要问题进行分析,阐述了BIM技术及小型装配式建筑的优势和特点。分别从乡村民居场地规划、方案优化设计、施工与运维管理、成本控制、文化传承、面临的挑战等方面进行了BIM及小型装配式建筑在乡村民居更新改造中的如何应用以及应用前景的论述。解决了目前乡村民居中普遍存在的一系列问题。可为乡村传统民居更新改造提供参考和借鉴,助力乡村振兴,推进美丽乡村建设。

基于BIM量化拟合回归分析的装配式建筑优化设计

装配式建筑是一种常见的建筑施工类型,具有工期短、节能环保等优势。为保证装配式建筑的建设质量,提出基于BIM量化拟合回归分析的装配式建筑优化设计方法:确定装配式建筑结构和参数,根据建筑使用要求选择合适的建筑材料;对组成装配式建筑的墙体、柱梁等构件进行提前预制,在BIM量化拟合回归分析技术的支持下,模拟建筑能耗与受力,确定建筑构件的装配角度,并通过构件连接以及碰撞检测等步骤,得出装配式建筑的优化设计结果。通过实例分析实验得出结论:与传统装配式建筑相比,优化设计装配式建筑的能耗明显降低,稳定系数提高到78.5mm/kN,说明优化设计装配式建筑在能耗和稳定性方面具有明显优势。

钛合金气门在高海拔环境中的应用优势与表面处理

在高海拔环境下,低温低压环境会导致柴油发动机的动力下降和燃烧不完全,这也会导致气门组件磨损加剧。虽然几十年来,气门制造技术已经得到了广泛探索,但是气门组件经常面临高温高压、频繁冲击和摩擦的严峻工作条件,导致摩擦磨损机制变得异常复杂,过去的气门制造优化措施并没有完全解决气门组件磨损的问题。为此,提出了一种新的解决方案,即使用铝化钛合金作为气门材料。该材料具有热强度高和重量轻的优点,非常适合用作柴油发动机气门材料。然而,由于钛铝合金的耐磨性存在短板,因此在投入实际使用之前,需要通过表面处理工艺来改善其摩擦学性能和疲劳特性。总结了多种钛铝合金表面处理方法的研究情况,包括超声表面轧制、激光表面熔覆技术、化学热处理工艺、激光表面微织构等。这些表面处理技术可以有效地改善铝化钛合金材料的摩擦学性能和疲劳特性,并消除对材料表面的负面影响。研究者们还通过使用不同的表面处理技术的复合处理来达到更好的效果。指出了未来的研究重点和方向是深入研究铝化钛合金的精确加工参数以及使用多种加工方式的可行性和作用。这将有助于更好地解决气门组件的磨损问题,提高柴油发动机的性能和可靠性。此外,还需要对铝化钛合金在其他领域的应用进行更广泛地研究和探索。

基于岗位能力培养的“机械装调技术”课程教学改革探索——以“二维工作台装调与应用”教学为例

以“二维工作台装调与应用”的教学为例,围绕人才目标实施项目化教学改革,构建“项目+任务”式教学内容。以高精密机械安装技术员岗位工作内容及要求为目标,精准分析学情,创新教学理念,通过在“机械装调技术”课程中实施“识-析-辨-学-练-用-赛”七步进阶的教学过程,完成培养从事机电设备、自动化设备和生产线安装、调试、运行、检测、维修等工作的高素质劳动者和技能型人才。

星载迈克尔逊干涉仪扫描角镜装调工艺研究

针对星载迈克尔逊干涉仪悬臂式扫描角镜组件装调维度多、装调精度高、检测困难等技术难点,提出了一种“向量解析+精密微动调整”方法,通过建立装调及检测基准、将角镜组件简化为空间点向量、采用“先法向后平面”的调整顺序、利用专用精密微动装置等措施,实现了空间多自由度角镜组件的高精度调整,角镜顶点位置对称度装调后达到8μm,优于0.01 mm的设计指标要求,有效提高了装调精度,缩短了装调周期。

Review of in-space assembly technologies

With the rapid development of space technology and the increasing demand for space missions,the traditional spacecraft manufacturing,deployment and launch methods have been unable to meet existing needs.In-space assembly(ISA)technologies can effectively adapt to the assembly of large space structures,improve spacecraft performance,and reduce operating costs.In this paper,the development and technologies for ISA are reviewed.ISA is classified from multiple angles,and the research status of ISA is shown clearly through the visual mapping knowledge domain.Then the development status of autonomous robot assembly in the United States,Europe,Japan,Canada and China is reviewed.Furthermore,the key technologies of ISA are analyzed from three aspects:assembly structure design,robot technologies and integrated management technologies.ISA technologies are still facing major challenges and need to be further explored to promote future development.Finally,future development trends and potential applications of ISA are given,which show that ISA will play a vital role in human space exploration in the future.