The roles of focal adhesion and cytoskeleton systems in fluid shear stress-induced endothelial cell response

Focal adhesions are polyproteins linked to extracellular matrix and cytoskeleton, which play an important role in the process of transforming force signals into intracellular chemical signals and subsequently triggering related physiological or pathological reactions. The cytoskeleton is a network of protein fibers in the cytoplasm, which is composed of microfilaments, microtubules, intermediate filaments, and cross-linked proteins. It is a very important structure for cells to maintain their basic morphology. This review summarizes the process of fluid shear stress transduction mediated by focal adhesion and the key role of the cytoskeleton in this process, which focuses on the focal adhesion and cytoskeleton systems. The important proteins involved in signal transduction in focal adhesion are introduced emphatically. The relationship between focal adhesion and mechanical transduction pathways are discussed. In this review, we discuss the relationship between fluid shear stress and associated diseases such as atherosclerosis, as well as its role in clinical research and drug development.     

人工湿地-微生物电解池耦合系统的脱氮特性

实验构建了人工湿地-微生物电解池耦合系统（CW-MEC），并考察了CW-MEC在阴极有无曝气及不同水力停留时间（HRT）的条件下对生活污水的处理效果。实验结果显示，降低HRT会让CW-MEC阴极、阳极的COD去除率由91.11%±7.76%、86.58%±9.54%降低为77.81%±14.84%、81.44%±11.11%，氨氮去除率由58.54%±5.80%、58.22%±5.03%降低为48.04%±12.94%、48.27%±13.40%；阴极增加曝气会让CW-MEC阴极、阳极的COD去除率分别提高到89.51%±3.92%、82.40%±1.63%，阴极氨氮去除率提高到71.51%±16.44%，而阳极氨氮去除率不受影响；增加阴极曝气条件后，系统阴、阳极开始有硝酸盐氮积累，而CW-MEC阴极的硝酸盐氮含量明显低于对照组（CW-MFC）；通过电化学性能分析，相对于CW-MFC系统，CW-MEC具有更低的内阻；通过微生物多样性分析，CW-MEC系统具有更丰富的微生物多样性。     

橡胶促进剂M废渣在沥青路面工程中的应用技术研究

基于橡胶促进剂M废渣含有硫成分,高温易熔化、增塑的性能特点,主要从M废渣改性沥青、改性沥青稳定剂,及复合改性沥青三个应用技术层面,探讨了橡胶促进剂M废渣作为沥青添加剂应用于沥青路面工程的可能性,对比分析了M废渣在各个应用中存在的优缺点.结果 表明,橡胶促进剂M废渣可以以M废渣改性沥青、稳定剂、复合改性沥青三种方式应用于沥青路面工程.其中M废渣改性沥青推荐适用于县道、乡道等低等级公路,但不适用于高等级公路.M废渣可作为稳定剂并能显著提高改性沥青的储存稳定性,但用量有限,可作为资源化利用M废渣的辅助用途.M废渣和废胎胶粉联合使用制备的复合改性沥青,技术指标满足规范要求,并改善了废胎胶粉改性沥青的黏度衰减问题,同时可节省基质沥青,可作为资源化利用M废渣的主要用途.     

基于CO2循环的低碳高效白云石煅烧新工艺

白云石是一种广泛应用的冶金、建材和化工原料。针对白云石煅烧过程中CO₂排放严重等问题，构建了基于CO₂循环载热与资源化回收的白云石低碳煅烧竖窑新工艺。通过白云石（CaCO₃·MgCO₃）煅烧过程的Gibbs自由能变计算，发现提高煅烧温度（50~100 K）可有效克服CO₂对反应的抑制作用；通过纯CO₂环境中CaCO₃分解过程的热重实验分析，验证了CO₂循环煅烧白云石煅烧的可行性；通过化学反应动力学计算，解析了全CO₂组分环境下CO₂压力对CaCO₃·MgCO₃高温分解过程的影响，并发现提高CO₂压力可促进气固传热，从而提升分解速率和改善矿料分解均匀性；对CO₂循环煅烧工艺系统能-质平衡计算表明：该工艺理论能耗仅为140 kg/(t 煅白)，且煅烧过程的CO₂排放降低70%以上，环境效益显著。     

无水硫酸镁催化剂在2,5-二氯硝基苯生产中的应用

介绍了以对二氯苯和浓硝酸为原料、无水硫酸镁为催化剂制取2,5-二氯硝基苯的工艺过程;分析了催化剂用量和催化剂循环利用对产物选择性的影响,确定了适宜的催化剂用量和催化剂酸化条件。     

水平管内R245fa/R141b沸腾换热特性的实验研究

针对新型混合工质R245fa/R141b，开展水平光滑管(外径10 mm)内工质沸腾换热特性的实验研究，对比纯工质与混合工质的换热性能及4种常用关联式的预测精度。结果表明：纯工质与混合工质的沸腾传热系数均随质量流速和热通量的增加而增大，随饱和压力的增加而减小；随干度的增加，沸腾传热系数均先增大后减小，即存在“过渡干度”，且混合工质的过渡干度大于纯工质；干度小于0.55时，混合工质传热系数小于纯工质；干度大于0.55后，混合工质的传热系数更高；随R245fa质量分数的增加，混合工质的沸腾传热系数增大。在所选关联式中，Gungor-Winterton关联式能准确地预测工质在光滑管内的沸腾换热特性，平均相对误差为16.67%。     

小庄煤矿液态CO2防灭火技术实践

针对小庄煤矿40203综放工作面采空区出现自然发火隐患问题,分析了该工作面自然发火原因、液态CO 2防灭火机理及施工工艺,成功实施了液态CO 2防灭火技术在现场的应用。在向40203综放工作面采空区灌注液态CO 2后,采空区出水温度由灌注前的36℃降至26.5℃,上隅角袋子墙内CO浓度由灌注前的0.0067%降至0.0051%,上隅角采空区19 m处CO浓度由灌注前的0.0072%降至0.0053%,采空区出水温度和CO浓度显著下降并维持稳定。实践表明,该技术成功遏制了采空区遗煤进一步氧化升温,消除了采空区自然发火隐患,保证了工作面的安全回采,也为矿井防灭火工作积累了可借鉴的实践经验。     

Isogeometric topology optimization based on energy penalization for symmetric structure

We present an energy penalization method for isogeometric topology optimization using moving morphable components (ITO–MMC), propose an ITO–MMC with an additional bilateral or periodic symmetric constraint for symmetric structures, and then extend the proposed energy penalization method to an ITO–MMC with a symmetric constraint. The energy penalization method can solve the problems of numerical instability and convergence for the ITO–MMC and the ITO–MMC subjected to the structural symmetric constraint with asymmetric loads. Topology optimization problems of asymmetric, bilateral symmetric, and periodic symmetric structures are discussed to validate the effectiveness of the proposed energy penalization approach. Compared with the conventional ITO–MMC, the energy penalization method for the ITO–MMC can improve the convergence rate from 18.6% to 44.5% for the optimization of the asymmetric structure. For the ITO–MMC under a bilateral symmetric constraint, the proposed method can reduce the objective value by 5.6% and obtain a final optimized topology that has a clear boundary with decreased iterations. For the ITO–MMC under a periodic symmetric constraint, the proposed energy penalization method can dramatically reduce the number of iterations and obtain a speedup of more than 2.