氯化聚乙烯对氯丁橡胶与甲基丙烯酸甲酯接枝共聚反应的影响

研究了高氯氯化聚乙烯(HCPE)对氯丁橡胶与甲基丙烯酸甲酯接枝共聚及其反应产物的影响。结果表明,HCPE能加快聚合速率,提高转化率、接枝效率和接枝度。含HCPE的产物,含有较高分子量的级份,分子量分布较宽,树脂相的分布比较均匀,并具有较好的机械性能和较高的粘接强度。     

The Anticancer Activity Conferred by the Mud Crab Antimicrobial Peptide Scyreprocin through Apoptosis and Membrane Disruption

Scyreprocin is an antimicrobial peptide first identified in the mud crab Scylla paramamosain. Herein, we showed that its recombinant product (rScyreprocin) could significantly inhibit the growth of human lung cancer NCI-H460 cells (H460), but showed no cytotoxicity to human lung fibroblasts (HFL1). rScyreprocin was a membrane-active peptide that firstly induced the generation of reactive oxygen species (ROS) in H460, and led to endoplasmic reticulum stress and Ca²⁺ release, which resulted in mitochondrial dysfunction and subsequently activation of caspase-3 cascades, and ultimately led to apoptosis. The comprehensive results indicated that rScyreprocin exerted anticancer activity by disrupting cell membrane and inducing apoptosis. The in vivo efficacy test demonstrated that intratumoral injection of rScyreprocin significantly inhibited the growth of H460 xenografts, which was close to that of the cisplatin (inhibition rate: 69.94% vs. 80.76%). Therefore, rScyreprocin is expected to become a promising candidate for the treatment of lung cancer.     

Molecular and Physiological Responses of Citrus sinensis Leaves to Long-Term Low pH Revealed by RNA-Seq Integrated with Targeted Metabolomics

Low pH-induced alterations in gene expression profiles and organic acids (OA) and free amino acid (FAA) abundances were investigated in sweet orange [Citrus sinensis (L.) Osbeck cv. Xuegan] leaves. We identified 503 downregulated and 349 upregulated genes in low pH-treated leaves. Further analysis indicated that low pH impaired light reaction and carbon fixation in photosynthetic organisms, thereby lowering photosynthesis in leaves. Low pH reduced carbon and carbohydrate metabolisms, OA biosynthesis and ATP production in leaves. Low pH downregulated the biosynthesis of nitrogen compounds, proteins, and FAAs in leaves, which might be conducive to maintaining energy homeostasis during ATP deprivation. Low pH-treated leaves displayed some adaptive responses to phosphate starvation, including phosphate recycling, lipid remodeling, and phosphate transport, thus enhancing leaf acid-tolerance. Low pH upregulated the expression of some reactive oxygen species (ROS) and aldehyde detoxifying enzyme (peroxidase and superoxidase) genes and the concentrations of some antioxidants (L-tryptophan, L-proline, nicotinic acid, pantothenic acid, and pyroglutamic acid), but it impaired the pentose phosphate pathway and V_E and secondary metabolite biosynthesis and downregulated the expression of some ROS and aldehyde detoxifying enzyme (ascorbate peroxidase, aldo-keto reductase, and 2-alkenal reductase) genes and the concentrations of some antioxidants (pyridoxine and γ-aminobutyric acid), thus disturbing the balance between production and detoxification of ROS and aldehydes and causing oxidative damage to leaves.     

空间信息的呈现界面对建筑火灾中寻路行为的影响

为了提高危机救援过程中团体内部与外部的空间共享效率,结合建筑火灾的动态建筑结构变化与人类空间信息的认知表征、空间信息的交互方式,设计了两种空间信息界面:静态朝向信息一致信息界面;动态朝向信息一致信息界面,探究动态环境中不同朝向信息对于寻路绩效的影响。通过Unity3D软件模拟实际空间环境的动态变化,采集虚拟环境中内部人员的寻路行为,并通过录像与访谈分析建筑内外人员的交互行为。实验结果表明:1)静态信息界面下寻路时间与路径更短,寻路过程中的错误路径更少,但交互行为更多。2)动态信息界面下寻路时间与路径更长,寻路过程中交互行为更少,但错误路径更多。研究结果可以为消防救援队伍的内外协同提供支持,提升救援效率。     

膨胀石墨对纯油的吸附性能

以硫酸为插层剂、过氧化氢为氧化荆,用化学法制备了膨胀石墨。用扫描电子显微镜（SEM）分析了膨胀石墨的孔状结构,测试了膨胀石墨对纯油的吸附量。结果表明：膨胀石墨具有明显的三级孔状结构,膨胀石墨对原油、齿轮油、液压油和汽油的最大吸附量分别为80、85、60和50g／g,这种结果与油品的粘度有关。     

Experimental and numerical study on aerodynamic noise of outdoor unit of room air conditioner with different grilles

The aerodynamic and aeroacoustic performances of outdoor unit with two different types of grille have been investigated in present study. Experimental results indicate that the grille sharp will affect the flow rate and increase broadband noise level of outdoor unit. Based on noise generation mechanism and CFD simulation, vortex shedding noise model and inlet turbulence noise model are adopted to predict the broadband noise level of outdoor unit. When vortex shedding noise is concerned, the wake parameters should be calculated at 3 mm downstream of grille to achieve good accuracy. Inlet turbulence noise is generated from the interaction between blade wake and the grille, and plays less important role in present outdoor unit configuration. In comparison with experimental results, it is shown that the broadband noise prediction method could provide reasonable accuracy and the error between prediction and experiment is less than 1 dBA.     

Effects of nanocrystalline ferrite particles on densification and magnetic properties of the NiCuZn ferrites

Effects of nanocrystalline ferrite particles addition on densification behavior and magnetic properties of the NiCuZn ferrites were investigated. It was confirmed that nanocrystalline ferrite particles enhanced densification of the samples obviously. The reason was attributed to the nanocrystalline particles, which spread around the micron-sized ferrite particles, increased contacting area and inter-diffusion of the particles. When the amount of nanocrystalline particles addition reached to 30 wt%, the samples obtained an approximate densification behavior as the 1.5 wt% Bi₂O₃ added samples. Due to relatively bigger grain size, higher sintering density and no different chemical composition sintering aids added, the sample with 30wt% nanocrystalline ferrite particles got the highest permeability and relatively high Q-factor when sintered at 900.     

循环冗余校验在TMS320C64x+DSP上的高效实现

介绍循环冗余校验CRC在TMS320C64x+系列DSP上的软件实现。给出了该实现方法的理论推导过程并提供了相应的软件实现代码。     

基于发送缓存的VideoStream调度算法研究及其FPGA实现

研究了 CDMA2000 1x EVDO 系统一种支持 VideoStream 业务的调度算法及 FPGA 实现;通过大量研究和设计,得到一种能保证性能和速度,叉适合硬件实现的调度算法。综合时选用 Altera 公司的 StratixⅡ系列 EP2S60F484C4芯片,并通过功能仿真验证了硬件实现的可行性和正确性。