科创中国

讨论了Outlast相变纱线和织物以及国产相变纱线及织物的研究进展;通过采用差示扫描量热(DSC)测试、电镜测试以及温度时间曲线的测试方法对上海第三十六棉纺针织服装厂研制的SL粘胶型相变调温纤维、纱线及织物的相变特性进行了初步探索.

The transient behavior of centrifugal pumps during transient operating periods,such as startup and stopping,has drawn more and more attention recently because of urgent needs in engineering.Up to now,almost all the existing studies on this behavior are limited to using water as working fluid.The study on the transient behavior related to solid-liquid two-phase flow has not been seen yet.In order to explore the transient characteristics of a high specific-speed centrifugal pump during startup period delivering the pure water and solid-liquid two-phase flow,the transient flows inside the pump are numerically simulated using the dynamic mesh method.The variable rotational speed and flow rate with time obtained from experiment are best fitted as the function of time,and are written into computational fluid dynamics(CFD)code-FLUENT by using a user defined function.The predicted heads are compared with experimental results when pumping pure water.The results show that the difference in the transient performance during startup period is very obvious between water and solid-liquid two-phase flow during the later stage of startup process.Moreover,the time for the solid-liquid two-phase flow to achieve a stable condition is longer than that for water.The solid-liquid two-phase flow results in a higher impeller shaft power,a larger dynamic reaction force,a more violent fluctuation in pressure and a reduced stable pressure rise comparing with water.The research may be useful to understanding on the transient behavior of a centrifugal pump under a solid-liquid two-phase flow during startup period.

Three dimensional(3D)displacements,which can be translated further into 3D strain,are key parameters for design,manufacturing and quality control.Using different optical setups,phase-shift methods,and algorithms,several different 3D electronic speckle pattern interferometry(ESPI)systems for displacement and strain measurements have been achieved and commercialized.This paper provides a review of the recent developments in ESPI systems for 3D displacement and strain measurement.After an overview of the fundamentals of ESPI theory,temporal phase-shift,and spatial phase-shift techniques,3D deformation measurements by the temporal phase-shift ESPI system,which is suited well for static measurement,and by the spatial phase-shift ESPI system,which is particularly useful for dynamic measurement,are discussed.For each method,the basic theory,a brief derivation and different optical layouts are presented.The state of art application,potential and limitation of the ESPI systems are shown and demonstrated.

针对具有不同动态非对称性的部分相容聚合物共混体系,阐述了用于表征和探测其相分离特征的流变学方法,包括小振幅振荡剪切考察时温叠加原理的有效性和温度扫描,以及稳态剪切温度扫描;并且分析了共混体系的复杂结构对温度依赖性形成差异的深层原因,总结比较了各方法应用时的优缺点及其针对不同强弱动态非对称体系的适用性.

指出了危险品供应链实验室的建设目的,指导思想及总体规划,并从危险品仓储管理实验,危险品追塑系统实验等6方面介绍了基于物联网技术的危险品供应链实验室方案设计内容,最后详细介绍了实验手段与环境设计内容及相关实验设备配置情况.

目的 探讨miR-21在大肠癌细胞迁移和侵袭中的作用及机制.方法 取大肠癌SW480细胞培养、传代,分为两组.观察组转染miR-21 mimics,对照组加入同浓度的miRNA mimics negative control.采用实时荧光定量PCR法检测细胞中miR-21的表达情况,采用Transwell小室检测细胞的迁移和侵袭能力,Western blot法检测上皮一间质转化(EMT)相关蛋白表达情况.结果 转染组miR-21的表达量、细胞的迁移和侵袭能力均明显高于对照组(P均<0.05);细胞中紧密连接蛋白(ZO-1)和上皮钙黏蛋白(E-cad)的表达明显降低、神经钙黏蛋白(N-cad)和转录因子Slug的表达明显升高,第10号染色体同源缺失性磷酸酶-张力蛋白(PTEN)表达明显降低、而磷酸化蛋白激酶B(p-Akt)表达明显升高(P均<0.05).结论 miR-21可促进人大肠癌细胞发生EMT发生细胞迁移和侵袭,其机制为下调PTEN蛋白表达、激活P13K/Akt,促进EMT.

采用废旧聚乙烯(PE)与硫酸钙晶须为原料,通过熔融挤出共混制得废旧PE/硫酸钙晶须复合材料,比较了经硅烷偶联剂KH-590改性与未改性的硫酸钙晶须用量对废旧PE/硫酸钙晶须复合材料力学性能的影响,分析硫酸钙晶须增强度旧PE的机理和废旧PE/硫酸钙晶须复合材料的微观结构.结果表明:当硫酸钙晶须用量为15%时,未改性硫酸钙晶须使复合材料的拉伸强度、冲击强度提高了23.1%、9.1%;改性硫酸钙晶须使复合材料的拉伸强度、冲击强度、弯曲强度提高了26.7%、15.6%和5 3%,其在废旧PE中分布均匀,能起到明显的增强作用.

针对结构相似度(SSIM)模型不能对模糊和高纹理图像进行较好的质量评价,提出一种基于相位一致结构相似度(MPCSSIM)的全参考图像质量评价方法.该方法保留SSIM中的亮度函数和对比度函数,将结构函数替换成相位一致函数,然后将三者结合起来进行质量评价.实验中LIVE数据库上的计算结果与主观评分的线性相关系数和斯皮尔曼相关系数分别为0.9501和0.9362.实验结果表明相位一致能够更好地提取图像的结构信息,该方法有较好的性能,能够更准确地评价模糊图像和高纹理图像的质量.

采用手工搅拌、高速研磨搅拌以及高速研磨搅拌加超声波震荡这3种方法对纳米SiO2进行分散处理,研究了不同处理方式下纳米SiO2对水泥浆体性能的影响.用扫描电镜(SEM)观测了浆体微观结构,并采用紫外-可见分光光度法测定了在不同分散方法下纳米SiO2的分散程度.结果表明,采用后2种方法处理的纳米SiO2分散程度更高,可大幅提高水泥砂浆的抗压、抗折强度,使砂浆水化产物结构均匀,更密实.

建立了蔬菜干制品中18种有机磷农药和拟除虫菊酯农药残留的在线凝胶渗透色谱一气相色谱/质谱(GPC-GC/MS)分析方法.样品以乙腈为提取剂超声波高速匀浆提取,提取液经ENVI.Carb固相萃取柱净化,除去样品中大部分的色素等干扰基质,再经在线GPC进一步净化除去大分子干扰物质,有效降低了样品基质带来的背景干扰.采用外标法定量,在质量浓度为0.02mg/kg,-0.5mg/kg有良好的线性关系,加标水平为0.4mg/kg时,18种农药的回收率基本都在80%-130%,相对标准偏差小于10%,检出限为0.001mg/kg-0.026mg/kg.经实验证明,该方法是一种快速,准确,灵敏度高的同时检测梅菜干中多种农药残留的检测方法.