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81.
世博园旧工业厂房钢结构屋架加固施工技术   总被引:1,自引:0,他引:1  
尤雪春  陆新辉  王彦韬  张迪 《建筑施工》2009,31(12):1024-1026
世博村E地块利用旧工业房作为新建高层办公楼的商业裙房,由于旧厂房钢屋架有很大一部分弦杆、腹杆的强度不符合设计要求,屋架杆件拼焊、节点板改造等加固工作量十分庞大,加固过程中对钢屋架变形、下挠、拼焊的控制要求相当严格。针对钢屋架加固的特点和难点,介绍了采用单边卸载+顶撑体系、焊接变形控制、桁架纠偏等一系列的关键技术,确保了钢结构屋架加固的顺利完成。  相似文献   
82.
陆新辉 《建筑施工》2009,31(12):1030-1032
上海世博村E地块新建主楼深基坑东、南两侧均为紧贴的待改建保留厂房,两者最小间距仅1.2m,故深基坑施工对保留厂房结构的保护和监测要求相当高。施工中从基坑围护设计、保留厂房地基加固、基坑开挖流程、施工进度控制等各方面采取合理的施工工艺和施工措施,确保了基坑及周边保留厂房结构的安全稳定,使深基坑开挖施工顺利完成。  相似文献   
83.
针对目前航天发射事故安全分析软件大多采用通用的建模仿真分析软件的问题,提出一种将"指标体系评估"、"概率风险评估"和"危害度及危害区域评估"三者相结合建立航天发射试验安全评估软件体系架构。依据航天事故的特点,结合现有的评估方法和我国航天任务的需要,通过指标体系优化评价对事故进行危害等级的评估,用概率风险评价进行事故发生概率的计算,将危害度及危害区域评价进行事故后果分析,得到航天发射试验安全评估"三步走"方法。分析结果证明:该软件可对航天发射试验进行全面的安全预测和危害后果分析,将为航天发射试验场的建立和发射任务的实施提供重要的数据及安全保障。  相似文献   
84.
杜欣慧  王茜 《电气技术》2012,(2):42-44,48
利用Analog公司2005年生产的电能计量专用芯片ADE7758设计一个三相电能表,采集数据准确,控制性能灵活且性价比高。本文阐述了基于ADE7758和STC89C52的电表的整体设计及工作原理,重点讲述ADE7758电能计量芯片的外围设计以及与STC89C52的通信连接。使用模块化思想和嵌套方法分别对硬件进行设计、对软件进行编程。  相似文献   
85.
Plant byproducts and waste present enormous environmental challenges and an opportunity for valorization and industrial application. Due to consumer demands for natural compounds, the evident paucity of novel antimicrobial agents against foodborne pathogens, and the urgent need to improve the arsenal against infectious diseases and antimicrobial resistance (AMR), plant byproduct compounds have attracted significant research interest. Emerging research highlighted their promising antimicrobial activity, yet the inhibitory mechanisms remain largely unexplored. Therefore, this review summarizes the overall research on the antimicrobial activity and inhibitory mechanisms of plant byproduct compounds. A total of 315 natural antimicrobials from plant byproducts, totaling 1338 minimum inhibitory concentrations (MIC) (in μg/mL) against a broad spectrum of bacteria, were identified, and a particular emphasis was given to compounds with high or good antimicrobial activity (typically <100 μg/mL MIC). Moreover, the antimicrobial mechanisms, particularly against bacterial pathogens, were discussed in-depth, summarizing the latest research on using natural compounds to combat pathogenic microorganisms and AMR. Furthermore, safety concerns, relevant legislation, consumer perspective, and current gaps in the valorization of plant byproducts–derived compounds were comprehensively discussed. This comprehensive review covering up-to-date information on antimicrobial activity and mechanisms represents a powerful tool for screening and selecting the most promising plant byproduct compounds and sources for developing novel antimicrobial agents.  相似文献   
86.
Microbial growth and fluctuations in environmental conditions have been shown to cause microbial contamination and deterioration of food. Thus, it is paramount to develop reliable strategies to effectively prevent the sale and consumption of contaminated or spoiled food. Responsive packaging systems are designed to react to specific stimuli in the food or environment, such as microorganisms or temperature, then implement an informational or corrective response. Informative responsive packaging is aimed at continuously monitoring the changes in food or environmental conditions and conveys this information to the users in real time. Meanwhile, packaging systems with the capacity to control contamination or deterioration are also of great interest. Encouragingly, corrective responsive packaging attempting to mitigate the adverse effects of condition fluctuations on food has been investigated. This packaging exerts its effects through the triggered release of active agents by environmental stimuli. In this review, informative and corrective responsive packaging is conceptualized clearly and concisely. The mechanism and characteristics of each type of packaging are discussed in depth. This review also summarized the latest research progress of responsive packaging and objectively appraised their advantages. Evidently, the mechanism through which packaging systems respond to microbial contamination and associated environmental factors was also highlighted. Moreover, risk concerns, related legislation, and consumer perspective in the application of responsive packaging are discussed as well. Broadly, this comprehensive review covering the latest information on responsive packaging aims to provide a timely reference for scientific research and offer guidance for presenting their applications in food industry.  相似文献   
87.
为实现人工窖泥发酵剂(APMSC)的品质控制,从前期开发的发酵剂配方中分别取出老熟窖泥、曲药、酒糟和黄水初步形成4个简化配方,采用扩增子测序和色谱技术比较了各配方发酵剂的微生物群落结构及香味物质含量差异。结果显示,各配方发酵剂样品中共检测到70个微生物操作分类单元(OTU),其中71.43%为各组样品共有,未检测到独有OTU。各配方样品的优势微生物均存在于其余分组中,仅物种相对丰度有所差异。根据酿酒有益微生物的丰度高低,选择了一种简化配方(无老熟窖泥作原料)发酵剂养护窖池,使酿造白酒的主体香味物质含量得到显著提高。结果表明,即使缺失了某一种培养原料,人工窖泥发酵剂的功能微生物物种也可能由其他原料补充,而原料种类的减少是实现发酵剂品质控制的主要途径。  相似文献   
88.
Guo  Zhide  Yang  Liu  Chen  Mei  Wen  Xuejun  Liu  Huanhuan  Li  Jingchao  Xu  Duo  An  Yuanyuan  Shi  Changrong  Li  Jindian  Su  Xinhui  Li  Zijing  Liu  Ting  Zhuang  Rongqiang  Zheng  Nanfeng  Zhu  Haibo  Zhang  Xianzhong 《Nano Research》2020,13(1):173-182

Vulnerable atherosclerotic plaques are responsible for most cardiovascular diseases (CVDs). Folate receptor (FR) positive activated macrophages were thought to be a prominent component in the development of vulnerable plaque. The objective of this study is to develop folate conjugated two-dimensional (2D) Pd@Au nanomaterials (Pd@Au-PEG-FA) for targeted multimodal imaging of the FRs in advanced atherosclerotic plaques. Pharmacokinetic and imaging studies (single photon emission computed tomography (SPECT), computed tomography (CT) and photoacoustic (PA) imaging) were performed to confirm the prolonged blood half-life and enrichment of radioactivity in atherosclerotic plaques. Strong signals were detected in vivo with SPECT, CT and PA imaging in heavy atherosclerotic plaques, which were significantly higher than those of the normal aortas after injection of Pd@Au-PEG-FA. Blocking studies with preinjection of excess FA could effectively reduce the targeting ability of Pd@Au-PEG-FA in atherosclerotic plaques, further demonstrating the specific binding of Pd@Au-PEG-FA for plaque lesions. Histopathological characterization revealed that the signal of probe was in accordance with the high-risk plaques. In summary, the Pd@Au-PEG-FA has favorable pharmacokinetic properties and provides a valuable approach for detecting high-risk plaques in the presence of FRs in atherosclerotic plaques.

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89.
主要叙述了基于PC104单板微机的触摸屏自动控制系统的软硬件的设计和实现。系统的硬件部分采用PC104单板微机作为中央处理器,用CPLD为核心器件设计接口电路;软件部分则采用C语言编写。通过这样能有效缩短开发周期,系统兼容性好、运行安全可靠。  相似文献   
90.
It is of great importance to reinforce electronic and ionic conductivity of Li4Ti5O12 electrodes to achieve fast reaction kinetics and good high‐power capability. Herein, for the first time, a dual strategy of combing N‐doped Li4Ti5O12 (N‐LTO) with highly conductive TiC/C skeleton to realize enhanced ultrafast Li ion storage is reported. Interlinked hydrothermal‐synthesized N‐LTO nanosheets are homogeneously decorated on the chemical vapor deposition (CVD) derived TiC/C nanowires forming binder‐free N‐LTO@TiC/C core–branch arrays. Positive advantages including large surface area, strong mechanical stability, and enhanced electronic/ionic conductivity are obtained in the designed integrated arrays and rooted upon synergistic TiC/C matrix and N doping. The above appealing features can effectively boost kinetic properties throughout the N‐LTO@TiC/C electrodes to realize outstanding high‐rate capability at different working temperatures (143 mAh g?1/10 C at 25 °C and 122 mAh g?1/50 C at 50 °C) and notable cycling stability with a capacity retention of 99.3% after 10 000 cycles at 10 C. Moreover, superior high‐rate cycling life is also demonstrated for the full cells with N‐LTO@TiC/C anode and LiFePO4 cathode. The dual strategy may provoke wide interests in fast energy storage areas and motivate the further performance improvement of power‐type lithium ion batteries (LIBs).  相似文献   
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