建筑结构控制爆破拆除的力学分析与应用

应用运动学、动力学理论建立建(构)筑物控爆坍落过程的力学模型,进而研究在非定常约束条件下坍落结构的力学特征。首次提出了采用延时起爆技术时,非自由质点系及其广义坐标应是建立在每一段位上的瞬间虚位移。在此基础上,分析求解运动过程中时控单元的质点自由度,为精确选定爆破部位及时序提供了设计理论和计算依据。同时,结合振动理论,将控爆时差、结构载荷分布调制为振动系统,形成坍落结构梁板单元的强迫振动,充分实现在运动中进一步解体、破碎其自身结构,并形成具有明显缓冲效果的下落过程。应用实践结果证明力学分析是正确的,为工程结构爆破拆除计算机辅助设计及动态模拟技术的有效应用奠定了基础。     

A novel pre-dilution,swirling jet diffuser to enhance effluent mixing: Hydrodynamics and dilution performance

Diffusers are widely-used to quickly dilute effluents in receiving water bodies. This study proposed a novel diffuser that pre-mixes effluent with ambient water before discharging and that uses the swirling jet to further enhance near-field dilution. The nozzle of the diffuser was examined in two ambient flow conditions: co-flow and counter-flow that are commonly-met in the environment such as oceans due to tidal effect. Physical experiments were first conducted in co-flow on its dilution performance and hydrodynamics, using heated water as the effluent. A 3-D CFD model was developed and calibrated the co-flow scenarios, and then used to investigate the diffuser in counter-flow. The results showed that the nozzle can effectively reduce the maximum temperature rise of the effluent by about 50 % before discharging. The swirling jet from the outlet has a larger shear area, half-width and entrainment rate, enabling the effluent to be rapidly diluted to a minimum of around 10 times at x/D = 6 in co-flow, whereas the dilution for conventional nozzles is about 1 because of the potential core. The flow amplification ratio (α) decreases gradually with increasing velocity ratio in co-flow but increases with increasing velocity ratio in counter-flow. The counter-flow reduces the water drawn into the device; however, the pre-dilution effect at the outlet remains stable. The near-field dilution in counter-flow was significantly enhanced than that in co-flow. Environmental regulations at outfalls and mixing zones can be more easily met using this novel diffuser.     

以新发展理念引领高校专业基础课教学改革

以“创新、协调、绿色、开放、共享”为内核的新发展理念，是对马克思主义发展理念的继承和发扬，极具时代精神，富含问题意识，为高校思想政治教育发展、教育教学改革实践提供了强大的理论支撑。本文以“通信原理”为例，阐述了新发展理念在课程改革中的思路和方法，实现了思想政治教育与专业基础课程有机融合，为深化高校教学改革、创新人才培养模式提供了思路。     

Cryptographic Lightweight Encryption Algorithm with Dimensionality Reduction in Edge Computing

Edge Computing is one of the radically evolving systems through generations as it is able to effectively meet the data saving standards of consumers, providers and the workers. Requisition for Edge Computing based items have been increasing tremendously. Apart from the advantages it holds, there remain lots of objections and restrictions, which hinders it from accomplishing the need of consumers all around the world. Some of the limitations are constraints on computing and hardware, functions and accessibility, remote administration and connectivity. There is also a backlog in security due to its inability to create a trust between devices involved in encryption and decryption. This is because security of data greatly depends upon faster encryption and decryption in order to transfer it. In addition, its devices are considerably exposed to side channel attacks, including Power Analysis attacks that are capable of overturning the process. Constrained space and the ability of it is one of the most challenging tasks. To prevail over from this issue we are proposing a Cryptographic Lightweight Encryption Algorithm with Dimensionality Reduction in Edge Computing. The t-Distributed Stochastic Neighbor Embedding is one of the efficient dimensionality reduction technique that greatly decreases the size of the non-linear data. The three dimensional image data obtained from the system, which are connected with it, are dimensionally reduced, and then lightweight encryption algorithm is employed. Hence, the security backlog can be solved effectively using this method.     

市售酒香精成分分析在酒类真实性鉴别中的应用

目的采用液相色谱及气相色谱技术,对白兰地及白酒香精的香气成分进行检测,分析香精与真酒样的相似程度。方法通过高效液相色谱及气相色谱检测,得到3批次白兰地香精及6批次白兰地真酒样的18种香气成分数据,通过气相色谱检测,得到2批次白酒香精及6批次白酒真酒样的14种香气成分数据,数据经过归一化处理后,使用SPSS22.0软件,进行聚类分析(clusteringanalysis)和主成分分析(principal component analysis, PCA)。结果经过聚类分析及主成分分析,均能将香精与真酒样进行区分。结论利用部分香气成分数据结合多元统计分析,能够区分香精及真酒样,为鉴别真假酒技术提供新思路。     

Identification of Host Cellular Protein Substrates of SARS-COV-2 Main Protease

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease-19 (COVID-19) being associated with severe pneumonia. Like with other viruses, the interaction of SARS-CoV-2 with host cell proteins is necessary for successful replication, and cleavage of cellular targets by the viral protease also may contribute to the pathogenesis, but knowledge about the human proteins that are processed by the main protease (3CLpro) of SARS-CoV-2 is still limited. We tested the prediction potentials of two different in silico methods for the identification of SARS-CoV-2 3CLpro cleavage sites in human proteins. Short stretches of homologous host-pathogen protein sequences (SSHHPS) that are present in SARS-CoV-2 polyprotein and human proteins were identified using BLAST analysis, and the NetCorona 1.0 webserver was used to successfully predict cleavage sites, although this method was primarily developed for SARS-CoV. Human C-terminal-binding protein 1 (CTBP1) was found to be cleaved in vitro by SARS-CoV-2 3CLpro, the existence of the cleavage site was proved experimentally by using a His₆-MBP-mEYFP recombinant substrate containing the predicted target sequence. Our results highlight both potentials and limitations of the tested algorithms. The identification of candidate host substrates of 3CLpro may help better develop an understanding of the molecular mechanisms behind the replication and pathogenesis of SARS-CoV-2.     

一种利用生产动态资料确定水驱前缘的方法

针对长庆油田低渗透储集层岩性致密、注水受效不均衡、单井产量低、平面非均质性强等导致地下水驱不均的问题,依据低渗透油藏水驱理论建立基础模型,并考虑注采井网中生产井的干扰,根据势的叠加原理,引入生产井影响因子系数,建立了井组单元内水驱前缘的简易确定方法。将该方法应用于鄂尔多斯盆地某超低渗透油藏加密调整部署,通过生产实例验证,该方法简便易行,计算结果可靠。     

盘县火腿自然发酵过程中理化和风味特征

分析盘县火腿自然发酵过程中理化特性和风味特征的变化，并结合香气活度值（odor activity value，OAV）和偏最小二乘回归（partial least squares regression，PLSR）分析确定盘县火腿主体香气成分。结果表明：盘县火腿理化特性在发酵过程中发生显著变化（P＜0.05），pH值和NaCl含量显著上升，而水分活度、水分含量和肌内脂肪含量显著下降，亮度值和黄度值呈持续下降趋势，而红度值先降低后升高；随着发酵的进行，盘县火腿中风味物质的种类从25 种增加至40 种，含量从（218.50±22.14） μg/kg上升至（1 044.49±51.47） μg/kg，其中醛类物质的种类和含量最丰富；OAV分析筛选出16 种主体香气物质，PLSR模型显示3-甲基丁醛、十二醛、十六醛、(Z)-9-十八烯醛和十八醛对盘县火腿肉香、清香和油脂香有显著贡献。     

汽车涂装废水处理技术的研究进展

汽车涂装中产生大量的工业废水，主要包括脱脂废水、磷化废水、电泳废水和喷漆废水等,其典型污染物为重金属离子、表面活性剂、油漆颗粒、磷酸盐等，是一类复杂及难处理的高浓度工业废水。依据废水中所含污染物的不同，对涂装各工序废水进行分质预处理可有效地去除磷酸盐、重金属离子、悬浮固体、油类物质等污染物，有利于减轻后续生物或高级处理单元的负荷，提高整个处理系统的效率。本文综述近年来汽车涂装废水处理方面的研究成果或实践，旨在总结预处理工艺及主体处理工艺的优点及存在的不足，希望为汽车涂装废水处理达标排放及循环回用提供一些借鉴。     

重庆主城区城市空间结构演变与优化——基于公共服务功能组织视角

城市空间结构与城市公共服务功能组织密切相关。重庆主城区作为典型的"多中心、组团式"城市,在城市公共服务功能的就近组织、公共服务需求的均衡化方面具有先天的优势。本文梳理重庆主城区空间结构的演进历程以及与公共服务需求变化的互动关系,辨识随着城市功能由生产向消费转型,空间面临的结构问题及其内在动因,借鉴马斯洛理论,提出顺应当前及未来公共服务需求层次的分异,城市空间结构应从"多中心、组团式"进一步向"分层多中心、组团式"优化,引导形成相对集中、功能综合的基层"小、微中心"体系,以有序组织公共服务功能,最大限度地减少非必要交通出行,降低居民出行的时耗,提升城市效率,并借鉴恩格尔系数构建衡量城市效率的评价框架,为破解山地城市空间结构问题,推动城市空间转型提供新的思考视角。