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51.
The inertness of injector inserts and insert packing materials, such as glass or fused silica wool, is tested by a procedure based on split injection and rapid isothermal chromatography. Resulting sharp peaks sensitively reveal peak deformation resulting from adsorptivity, acid/base interaction, and excessive retention power. Degradation of labile components is detected by loss of material and degradation products. Adsorptivity was no problem on injecting 300 ng amounts. Degradation only occurred for raw wools; however, the retention power of some wools seemed unnecessarily high. On injection of smaller quantities, degradation remained similar, but adsorptivity increased significantly. 相似文献
52.
Vijaya Gowri Ayyappan Shashikant Shivaji Vhatkar Somashree Bose Srinivasan Sampath Sujoy K. Das Debasis Samanta Asit Baran Mandal 《印度化学会志》2022,99(1):100278
Bacterial cellulose (BC), derived from kombucha scoby have extraordinary organoleptic properties suitable for development of leather-like materials. An improvement in physical and mechanical property is desirable for the practical applications. This work deals with the treatment of BC by incorporations of three different nanomaterials such as gold nanoparticles (AuNP), silver nanoparticles (AgNP) and graphene oxide (GO). Achieving combined benefits via synergic interactions of different nanomaterials is the major objective herein. While graphene oxide can influence some of the parameters related to mechanical properties, silver nanomaterials can offer antibacterial characteristics. Gold nano materials can bridge the BC/silver/graphene oxide as well as provide the desirable aesthetic colour. Different physical chemical and mechanical characteristics were studied in detail. For example, changes in morphology by imaging fiber network were studied using scanning electron microscopy. Fibre properties were studied by Small Angle X-Ray Scattering (SAXS) and X-Ray Diffraction (XRD). Elemental composition was studied by X-ray photoelectron spectroscopy (XPS) analysis and Raman analysis. The improvement of hydrophobicity was studied by Contact angle meter. Thermal analysis was performed using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). A Picture was provided in ESI to show the modified material's leather-like appearances. 相似文献
53.
Qiao Dong 《Accreditation and quality assurance》2002,7(4):171-172
This document gives a brief introduction to CNACL (China National Accreditation Committee for Laboratories). Laboratory accreditation
in China is integrally administrated by the China State Bureau of Quality and Technical Supervision, a government administrative
department of China State Council, which authorizes CNACL to implement Chinese laboratory accreditation activities. CNACL
was established on September 20, 1994. It is a full member of both ILAC (International Laboratory Accreditation Cooperation),
and APLAC (Asia Pacific laboratory Accreditation Cooperation), and signed the APLAC MRA (Mutual Recognition Arrangement) in
New Delhi, India on December 3, 1999. CNACL carries out laboratory accreditation activities in full compliance with international
general criteria. Its operation complies with ISO/IEC Guide 58 (1993), ISO/IEC 17025 (1999), ISO/IEC Guide 43 (1997) and other
international standards. 相似文献
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Ricardo Q. Aucélio Roseli Martins de SouzaReinaldo Calixto de Campos Norbert MiekeleyCarmem L. Porto da Silveira 《Spectrochimica Acta Part B: Atomic Spectroscopy》2007
The determination of trace metals in lubricating oils using atomic spectrometric methods is reviewed. The importance of such analyses for technical diagnostics as well as the specific sample characteristics related to the analyte form (metallo-organic and metal particles) is discussed. Problems related to sample pre-treatment for appropriate sample introduction and calibration are addressed as well as the strategies to overcome them. Recent trends aimed at simplifying sample manipulation are presented. The applications and scope of AAS, ICP OES and ICP MS techniques for the determination of trace metals in lubricating oil is individually discussed, as well as some present instrumental trends. 相似文献
56.
针对舰船装备软件接口交互信息量大,利用现有动态测试技术对此类软件开展测试工作时效率较低,自动化测试水平亟待提高的现状,归纳分析了舰船装备软件测试系统的主要能力需求,研究了接口协议形式化、测试用例自动生成、测试用例自动驱动、通信接口转换等关键技术,并以上述技术为基础给出了舰船装备软件测试系统的体系架构设计方案,进而实现了一种基于LoadRunner自动化应用程序接口(LoadRunner Automation API)的舰船装备软件测试系统,为舰船装备软件提供了一种可行的自动化测试手段;该测试系统主要包括测试管理模块、测试用例生成模块、测试用例驱动模块和数据收集与分析模块;采用该测试系统能够有效提高舰船装备软件的测试效率。 相似文献
57.
Sahar Masoumeh Ghorbanpour Dr. Shihui Wen Prof. Tu'uhevaha J Kaitu'u-Lino Prof. Natalie J. Hannan Prof. Dayong Jin Assoc. Prof. Lana McClements 《Angewandte Chemie (International ed. in English)》2023,62(26):e202301193
Preeclampsia is a heterogeneous and multiorgan cardiovascular disorder of pregnancy. Here, we report the development of a novel strip-based lateral flow assay (LFA) using lanthanide-doped upconversion nanoparticles conjugated to antibodies targeting two different biomarkers for detection of preeclampsia. We first measured circulating plasma FKBPL and CD44 protein concentrations from individuals with early-onset preeclampsia (EOPE), using ELISA. We confirmed that the CD44/FKBPL ratio is reduced in EOPE with a good diagnostic potential. Using our rapid LFA prototypes, we achieved an improved lower limit of detection: 10 pg ml−1 for FKBPL and 15 pg ml−1 for CD44, which is more than one order lower than the standard ELISA method. Using clinical samples, a cut-off value of 1.24 for CD44/FKBPL ratio provided positive predictive value of 100 % and the negative predictive value of 91 %. Our LFA shows promise as a rapid and highly sensitive point-of-care test for preeclampsia. 相似文献
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