基于易损性的RC空间框架填充墙结构连续倒塌能力分析

为研究填充墙对RC空间框架抗竖向连续倒塌能力的影响,对一栋6层双跨RC框架结构采用OpenSees有限元软件进行了建模,利用集中塑性的beamWithHinges单元模拟填充墙的性能。考虑到结构的不确定性,在有限元模型的基础上采用改进的拉丁超立方体抽样法获得了性能不同的100个纯框架结构和100个框架填充墙结构,并采用PDA方法和竖向IDA方法对取得的样本进行了易损性分析和对比。分析结果表明：填充墙提高了框架结构的抗倒塌能力,发生连续倒塌概率相同的情况下,框架填充墙结构的承载能力要比纯框架结构的高10%~20%。此外,两种分析方法对纯框架结构的抗连续倒塌能力分析差别较小,而对于带填充墙的框架结构,PDA方法计算结果则偏于保守。     

超长隔震结构抗震性能与抗倒塌能力研究

采用增量动力分析(Incremental Dynamic Analysis,IDA)方法,得到了整体式与多塔式超长隔震结构进入各破坏状态的地震峰值加速度,分析了结构的抗震性能与抗倒塌能力。IDA分析结果表明:与多塔结构相比,整体式结构更易发生破坏,所以多塔结构的抗倒塌能力略强于整体结构,但两个结构在设计大震下的倒塌概率都小于5%,可以认为能达到大震不倒的安全要求。     

Numerical study of the static and dynamic characteristics of reinforced concrete cassette structures for high‐rise buildings

High‐rise buildings are extensively built in China, and the structure of these buildings is composed of different types of conventional system of which framed structures are more commonly employed. A new cassette structure with advantageous performance properties is proposed. Static and dynamic numerical simulations were applied to investigate the characteristics of this new structure. First, the components and other details are presented. A comparative analysis was conducted between the cassette structure and traditional structures using eight finite models with fiber elements in three different heights. A static pushover analysis and an incremental dynamic analysis were conducted based on 18 near‐ground motion records recommended by the Federal Emergency Management Agency. The seismic characteristics, deformation curve, interstory drift, roof displacement, and fragility curve are investigated. Based on the analysis of the models with three different heights and the variety of seismic records, the economic advantage and application of cassette structures for building industrialization are also discussed.     

Investigating the driving factors of regional CO2 emissions in China using the IDA-PDA-MMI method

In this paper, we systematically summarized existing research on the driving factors of CO₂ emissions and found that changes in technology gap may be one of the key driving factors of CO₂ emissions. Technology efficiency, technology progress, and technology gap were decomposed by using the Meta-frontier Malmquist index (MMI), which was then combined it with the Index Decomposition Analysis (IDA) and the Production-theoretical Decomposition Analysis (PDA). Our framework was applied to Chinese provincial data from 2000 to 2016. We identified nine factors to explain changes of regional CO₂ emissions. Results demonstrate that economic scale, energy technology efficiency, and output technology efficiency increased CO₂ emissions in Eastern, Central, and Western regions of China, with the economic scale being the largest contributor. Energy structure, energy intensity, energy technology progress, and output technology progress decreased regional CO₂ emissions, with the energy technology progress playing the strongest role. Energy technology gap and output technology gap led to an increase in CO₂ emissions in Central China and, to a lesser extent, in Western China. The effects of each driving factor on CO₂ emissions varied across provinces. Finally, policy implications are suggested to reduce CO₂ emissions in China.     

亚氨基二乙酸合成工艺

综述了亚氨基二乙酸合成方法的研究现状,重点介绍了具有工业前景的合成路线及最新的研究结果。     

基于RS纠删码的信息分散算法

利用基于RS纠删码的信息分散算法可构建高顽存的分布式存储系统。RS纠删码的编/译码速率是衡量其可用性的一个重要指标。对RS纠删码的纠删原理进行了理论分析,讨论了编/译码运算所在的伽罗瓦域,基于伽罗瓦域算术运算的特征设计了双表法以提高编/译码速率。最后对该信息分散算法的效率进行了理论分析和实验测试。测试结果表明,该信息分散算法可提供18Mbps的编/译码速率,基于该测试结果分析了基于RS纠删码的信息分散算法的适用环境,指出信息分散算法未来的研究方向。     

亚氨基二乙酸的生产工艺评述

综述了亚氨基二乙酸(IDA)的氢氰酸法、二乙醇胺法、亚氨基二乙腈水解法、氨代氯乙酸法、氯乙酸甘氨酸法等主要合成工艺,介绍了其在除草剂草甘膦生产中的应用。     

近场地震作用下某高面板堆石坝抗震性能评估

大坝抗震性能评估能够综合分析坝体在不同地震动强度地震动作用下发生的震损情况及可能造成的震害风险,是近年来坝工领域抗震研究的热点之一。鉴于目前近场地震作用下坝体的抗震研究相对较少,讨论近远场地震动作用下某高面板堆石坝大坝的易损性和震害风险的差异。通过采用增量动力分析方法(IDA)得到坝体的易损性曲线,并根据坝址地震概率模型得到近远场地震作用下的坝体震害风险。研究结果表明,相较于远场地震,近场地震对高面板堆石坝的易损性更高,造成的震损程度更大。大坝在近场地震作用下发生严重破坏的风险值为0.083,对应大坝的震害风险为不太可能状态。近场地震动情况下大坝发生轻微破坏、中等破坏和较重破坏的震害风险概率比远场地震动作用下的各个性能水准对应的震害风险概率略高,说明仅考虑远场地震动作用会低估土石坝震害风险概率。高面板堆石坝的地震易损性分析和震害风险评估能够对大坝抗震性能进行系统的综合性评估。研究结果可为坝址在近断层区域的大坝抗震设计和加固提供参考。     

条件均值谱选取记录的结构抗倒塌易损性分析

以抗倒塌易损性分析方法中的强震记录选取环节为研究对象,为了更好体现不同场址的地震动危险性差异,利用目标地区地震概率危险性分析的设定地震解耦结果构建条件均值谱（CMS）,进而将其进行多次调幅得到对应的目标谱,将匹配选波结果作为增量动力分析方法（IDA）的输入.以自振周期为0.5、1.0和1.5 s的3个平面框架为算例,在中国两个城市的地震安全性评价工作的基础上构建CMS谱,进行IDA分析,并将与当地一致概率谱、罕遇地震规范谱以及ATC63数据集得到的结果进行对比讨论,结果表明基于规范目标谱得到的抗倒塌易损性概率曲线最陡峭,基于一致概率谱与ATC63数据集得到的抗倒塌易损性概率曲线次之,CMS对应的抗倒塌易损性概率曲线最平缓.同时,对于较长周期的1.5 s结构,本文建议采用包络CMS谱来考虑多阶振型的影响,否则采用单点周期CMS谱会使得倒塌易损性计算结果显著低估实际的倒塌超越概率.     

超高效液相-质谱联用法测定化妆品中9种禁用激素

建立化妆品中非法添加的9种糖皮质激素的快速测定方法。采用超高效液相色谱-串联质谱法(UPLC-MS/MS),以ACQUITY UPLC~BEN C18色谱柱(50 mm×2.1 mm,1.7μm),流动相采用甲醇-水,电喷雾电离(ESI)联合相关信息扫描(IDA)与增强离子扫描(EPI)的扫描方式,对化妆品中非法添加的9种糖皮质激素成分进行快速定性分析,检测限低于0.4μg/m L。