Detection of captopril based on its enhanced resonance light scattering signals of fluorosurfactant-capped gold nanoparticles

In this study, based on its enhancement effect on resonance light scattering (RLS) of fluorosurfactant (FSN)-capped gold nanoparticles (GNPs), we reported a simple approach for the rapid sensing of captopril. Under optimum conditions, the lowest detectable concentration of captopril through this approach (S/N=3) was 0.01μg/mL. The calibration curve was linear over the range of 0.08-4.0μg/mL for the detection of captopril. The recoveries of captopril were found to fall in the range between 99% and 100%. We have validated the applicability of our method through the analyses of captopril in pharmaceutical formulations. Good agreements were obtained for the determination of captopril between the present approach and official method.     

如何熟练掌握车身钣金件手工整形方法(中)

<正>修平刀或手顶铁无法到达的凹陷,则应采用尖头工具(各种撬镐)撬起修复,如图10所示。将尖锤插入一个排水孔或门背后的孔内就可以撬凹陷处,既不需拆下车门内的装饰件,也不需要在外表面钻孔拉出凹陷。用尖头工具整修时,加力不可太大,从凹陷最低点开始逐步撬起。敲击时,应注意敲击顺序和敲击点的分布,如图10所示。     

纳米SiO2制备无毒疏水海洋防污涂料

以有机硅改性丙烯酸树脂作为成膜物质,通过在常规颜填料中添加疏水型纳米二氧化硅,对涂料的表面结构进行改性,制备出具有微米-纳米阶层结构的无毒疏水海洋防污涂料.讨论了颜填料加入量对涂膜附着力的影响、纳米SiO2加入量对水滴与涂膜表面接触角的影响.结果表明:颜填料的质量分数为31%时,涂膜附着力为1级;纳米二氧化硅的加入量占颜填料总质量为35%时, 水滴与涂膜表面接触角为126°.     

聚丙烯的共混改性研究

选用麦秸纤维对聚丙烯进行改性,研究了麦秸纤维含量和偶联剂种类对复合材料力学性能的影响。采用扫描电镜、体视显微镜分别观察了麦秸纤维的结构及其在聚丙烯中的分散性。结果表明,麦秸纤维经KH550表面处理剂处理后,含量为25％左右时,在聚丙烯基体中能保持均匀分散状态,且增强效果最佳。     

硅烷偶联剂对沥青阻燃剂表面改性研究

介绍了硅烷偶联剂表面改性沥青阻燃剂的原理和方法,确定了其最佳用量;通过红外光谱、热重分析等手段,对表面改性前后沥青阻燃剂的结构与性能进行了表征;研究了表面改性前后沥青阻燃剂的分散效果;对比分析了表面改性对沥青阻燃剂亲油性和亲水性的影响.结果表明,硅烷偶联剂与沥青阻燃剂发生了明显的物理化学作用,降低了沥青阻燃剂的表面极性,其最佳用量为沥青阻燃剂的0.95%;表面改性增强了沥青阻燃剂的热稳定性、分散性和亲油性,从而改善了沥青阻燃剂与沥青的相容性.     

混凝土温度裂缝的成因与防治

温度裂缝是混凝土结构中普遍存在的一种现象,主要是由于在混凝土硬化期间水泥放出大量水化热,内部温度不断上升,在表面产生     

旧水泥砼路面罩面技术与计量

概述 我国南方的水泥混凝土路面,由于诸多原因出现了不同程度的病害,如断板、表面磨损、错台等。如不及时进行有效的维护,将使路面使用性能降低,严重影响服务水平。我国目前普遍采用挖除出现病害的水泥板块进行快速修补的方法进行养护,但这种处理方法费用高且要经常性的养护,工作量大。基于这种养护方法的缺点,我国近几年出现了一种全新的水泥砼路面养护技术,     

A study on dynamic response of cable-seabed interaction

A numerical method is developed to investigate the dynamic response of cable-seabed interaction in this paper. The motion of cable is described by the Lumped Parameter Method, while the seabed, unlike the prevailing simplified model of elastic foundation, is modeled as an irregular continuous rigid surface with rebound and friction existing, and the forces exerted by the seabed consist of normal counterforce and isotropic tangential Coulomb friction resistance. To describe the detailed dynamic response, two coefficients are introduced by analogy with the theory of rigid body collision with friction. The cable-seabed kinematic and dynamic contact conditions are formulated subsequently, and are used to incorporate the seabed effect into the cable dynamics to produce a set of ordinary differential governing equations. In this paper, we employ 4th order Runge-Kutta method to solve these equations. Several simulation cases are presented to illustrate the seabed effect. The results show that friction and impact have a prominent influence on the statics and dynamics of the cable.     

带表面裂纹连续梁损伤识别的曲率模态小波分析

以带横向非对称非贯通表面裂纹的连续梁为研究对象,利用小波奇异性检测原理,提出了带表面裂纹连续梁损伤识别小波分析方法.以带表面裂纹连续梁三维有限元分析求解梁的位移模态为基础,利用中心差分法得到梁的曲率模态,再用sym4小波对曲率模态进行连续小波变换,根据小波系数模极大值识别损伤位置,以一个三跨连续梁内两处半椭圆形表面裂纹的损伤识别为例,通过数值计算分析,验证了方法的有效性.同时,计算结果表明,运用曲率模态小波变换识别连续梁损伤比基本振型的小波变换方法更为准确、有效.该研究对带表面裂纹结构的损伤诊断应用具有参考价值.     

SPJ型遇水膨胀橡胶

(1)局部遇水或受潮后会产生比原来大2-3倍的体积膨胀率并充满接触部位所有不规则表面、空穴及间隙,同时产生一定接触压力,阻止水份渗漏;