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991.
介绍了攀钢HC冷连轧机的特征,分析了影响冷轧产品厚度控制的主要因素,并结合生产实际情况,提出了提高厚度精度控制的有效措施。 相似文献
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Abstract Kinetics data of sulfidation were determined by the silver strip corrosion test method of on jet fuel. The corrosion rate was measured in different sulfur concentrations by the weight gain of silver films in unit time per unit area. A dynamic equation of sulfidation was finally obtained by linear regression under atmospheric pressure. 相似文献
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《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(12):2434-2442
ABSTRACTA time-resolved fluorescent immunochromatographic assay (TRFICA) was successfully developed for the sensitive, simultaneous, and quantitative detection of aflatoxin B1 (AFB1) and zearalenone (ZEN) in Chinese herbal medicines. Eu-nanospheres (EuNPs) with unique optical properties increased the stability and sensitivity of the immunochromatographic assay. To obtain stable quantitative results, we applied a three-label system in which monoclonal antibodies for AFB1 and ZEN were conjugated to the EuNPs as detection probes on the test line (T line), and EuNP-labelled chicken IgY conjugates acted as the reference on the control line (C line). The fluorescence intensities of the T and C lines were recorded, and the T/C ratio was employed as the quantitative signal for the elimination of strip variation and matrix effects. The parameters that affected the TRFICA were optimised. Under optimal conditions, the established TRFICA gave good linear ranges from 0.60 μg/kg to 3.92 μg/kg for AFB1 and from 0.40 μg/kg to 1.28 μg/kg for ZEN. The limits of detection for AFB1 and ZEN were as low as 0.60 and 0.40 μg/kg, respectively, in Chinese herbal medicines Semen coicis, Rhizoma dioscoreae, and Platycodon grandiflorus, respectively. The average recoveries of the spiked samples were 73%–95% for AFB1 and 75.83%–90% for ZEN, both with a relative standard deviation of < 9.08%. The results of 15 actual samples detected by the developed TRFICA showed a satisfactory correlation with those of ultra-performance liquid chromatography tandem mass spectrometry. Therefore, the TRFICA is a simple, rapid, and sensitive approach to quantitatively detect mycotoxins in Chinese herbal medicines. 相似文献
996.
胶体金免疫层析技术具有快速、简便、特异、敏感等特点, 弥补了真菌毒素传统检测方法的不足, 适用于真菌毒素快速现场筛选。本文主要介绍了胶体金免疫层析技术的原理及其在真菌毒素快速检测中的应用及发展前景。 相似文献
997.
Won‐Bo Shim Jeong‐Sook Kim Min‐Gon Kim Duck‐Hwa Chung 《Journal of food science》2013,78(10):M1575-M1581
A rapid immunochromatographic (ICG) strip based on a conjugate of colloidal gold and monoclonal antibody (mAb) was developed for the rapid, sensitive, and on‐site detection of sulfamethazine in meat and egg samples. The detection limit of the ICG strip is 2 ng/mL, and the assay can be completed in 10 min. A cross‐reactivity test indicated that the ICG strip was highly specific to sulfamethazine with no cross‐reaction with sulfonamide compounds and other antibiotics. The results of the recovery test from meat and egg samples spiked with sulfamethazine were in good agreement with those obtained by the indirect competitive enzyme‐linked immunosorbent assay. These results demonstrated that the ICG strip can be used as a rapid and qualitative tool for on‐site screening of sulfamethazine in meat and egg samples. 相似文献
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采用低成本的合金成分设计体系,通过连铸连轧和酸轧工序,以及低温退火的连续热镀锌生产工艺,成功开发了0.3~2.5 mm厚570 MPa级高强度热镀锌结构带钢。热连轧精轧出口温度为870 ℃,采取前段层流冷却,卷取温度为600 ℃,热镀锌工艺采用均热温度为605 ℃的不完全退火工艺;产品屈服强度Rp0.2为592~619 MPa,抗拉强度Rm为609~638 MPa,伸长率A50为6.5%~15%,组织性能均满足标准及用户要求,实现了批量稳定的工业化试制生产。 相似文献