UPLC-MS-MS测定红茶中的茶黄素含量

建立了一种快速测定红茶中4种茶黄素(茶黄素、茶黄素-3-没食子酸酯、茶黄素-3'-没食了酸酯和茶黄素-3,3'-双没食了酸酯)的超高效液相色谱串联质谱的分析方法。样品用70%的甲醇水浴提取,采用Waters ACQUITY BEH C18色谱柱分离,串联四级杆质谱多反应离子监测,外标法定量;色谱系统流速为250μL/min,柱温为30℃,流动相为0.1%甲酸和乙腈,梯度洗脱。结果表明,4种茶黄素在检测范围内线性关系良好,相关系数大于0.995,平均回收率在91.95%~105.37%之间,RSD(n=5)在2.37%~4.03%;方法的检出限在13.2~19.1 ng/m L,方法的定量限在39.7~52.6 ng/m L。所测红茶茶黄素含量为3.32 mg/g、茶黄素-3-没食子酸酯含量为1.96 mg/g、茶黄素-3'-没食了酸酯含量为1.48 mg/g、茶黄素-3,3'-双没食了酸酯0.70 mg/g,茶黄素总量为0.75%。该检测方法能快速检测红茶中的茶黄素含量,能有效分析评价红茶的品质,合理控制红茶生产质量。     

FLUKE5500A检定及数据管理系统的开发与应用

介绍FLUKE5500A检定及数据管理系统的开发和应用情况,对系统的组成和功能模块作了详细说明.该系统的应用,实现了自动检定直流电压、直流电流、交流电压、交流电流、频率和电阻等仪器仪表,以及可以对指示仪表或数表进行不确定度评定:实现了根据相关检定规程自动处理测量结果;实现了自动生成证书.     

具有马氏体组织的TC11合金两相区变形的组织机制及工艺优化

采用等温压缩实验研究了具有马氏体组织的TC11合金在两相区的变形行为及微观组织演变规律。等温压缩实验在Gleeble3500热模拟实验机上进行,其中变形温度为920～980℃,应变速率为0.1～10s-1,变形量为70%。基于动态材料模型(DMM),建立了具有马氏体组织的TC11合金两相区变形的热加工图。在低温(<940℃)区和高温(>960℃)高应变速率(>1s-1)区域存在失稳现象,主要表现为低温时的表面开裂和高应变速率区的绝热剪切带;在塑性加工安全区域,分别对应着片层扭折和片层球化的组织机制,其中变形量70%时应变速率敏感因子在980℃,0.1s-1时取得峰值为0.73,此时可得到完全球化的细晶组织(等轴α尺寸约为0.7μm)。具有马氏体组织的TC11合金两相区变形时,为避免缺陷并得到细的等轴组织,合适的加工工艺为温度:950～980℃,应变速率0.1～1s-1。     

运动序列的短期统计特性

本文利用动态图象序列研究了运动序列的短期统计特性,对每个宏块经过压缩后所产生的比特数进行了分析,研究了量化比例因子和量化加权矩阵对短期统计特性的影响.统计结果表明,量化比例因子对每个宏块比特数的概率分布影响最为明显,量化加权矩阵对分布特性的轮廓影响很小,当量化比较精细时图象内容对分布特性的低比特部分影响比较明显,而粗量化时它的影响较弱.     

The first materials science investigations of plutonium in the laboratories of NII-9

The formation of the institute NII-9 (now the State Science Center of the Russian Federation—A. A. Bochvar All-Russia Scientific-Research Institute of Standardization in Machine Engineering), by a decree of the State Committee on Defense, in 1945 in Moscow and the production at this Institute in 1948 of substantial (milligram) quantities of metallic plutonium from uranium blocks irradiated in the F-1 reactor are recounted. Data on the organization of the work and the creation of special equipment and methods for performing investigations on microsamples of a radioactive, toxic, chemically active material are presented. These investigations led to the discovery of six allotropic modifications of plutonium the temperature ranges of their stability, the melting temperature, the characteristic features of the volume and temperature expansion at phase transitions, and the mechanical properties of the phases. The participation of the Institute staff and of A. A. Bochvar himself in the fabrication of the plutonium warhead in 1949 for the first Soviet atomic bomb is reflected. The directions of the investigations of plutonium performed in subsequent years are indicated. State Science Center of the Russian Federation—A. A. Bochvar All-Russia Scientific-Research Institute of Standardization in Machine Engineering. Translated from Atomnaya énergiya, Vol. 87, No. 3, pp. 170–174, September, 1999.     

抽油泵柱塞拉伤失效原因分析

在分析抽油泵柱塞失效特征的基础上, 推断出拉伤失效是砂粒在柱塞端部锥面和泵筒内表面之间产生自锁所致。通过建立砂粒自锁条件及实测长石砂岩、石英砂岩与泵筒镀铬层或氮化层的滑动摩擦系数值, 证实了对柱塞拉伤失效原因的推测是正确的。因此, 为避免砂粒产生自锁, 对于采用镀铬泵筒的抽油泵, 柱塞的锥面角θ值应大于或等于１７－５°; 对于３８ＣｒＭｏＡｌ 氮化泵筒, 柱塞的θ值则应大于或等于１６－５°。应选用与石英砂岩摩擦系数较小的材料制造抽油泵泵筒。     

智能型示功机设计与应用

本文介绍了减振器多速程控示功机的测控原理和微机闭环系统在示功机转速控制系统中的应用,给出了相应的数学模型,并通过理论和实际结果分析指出了它的应用价值。     

Preparation of biodegradable polymer microspheres encapsulating protein with micron sizes

Biodegradable polymer poly-D,L -lactide-polyethylene glycol (PLA-PEG) was synthesized with stannous octoate (SnOc₂) as catalyst by a cationic ring-opening polymerization. The molecular weight of PLA-PEG is the highest at a content of 0.1% SnOc₂. The PLA-PEG microspheres carrying protein were prepared by a solvent evaporation composite emulsion technique with a narrow size range (1–2 μm). The sizes of PLA-PEG microspheres increased with the increase of the molecular weight of PLA-PEG. The PEG in PLA-PEG (10%) significantly improved the size control of the microspheres of the PLA family as a drug carrier matrix. Polyvinyl alcohol (PVA) aqueous solution was used as dispersion medium for microsphere preparation. The concentration of the PVA solution can affect the size of the PLA-PEG microspheres. The differential scanning calorimetry data showed that the PLA-PEG microspheres can efficiently encapsulate the protein and that the crystalline of the microspheres carrying protein was lower than that of the nonprotein-loading microspheres. The amount of protein carried in the PLA-PEG microspheres was related to the nature of the protein itself. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 583–590, 1997     

天然气组成分析及物性参数计算标准对煤制气的适用性研究

分析了现行天然气的组成分析标准和物性参数计算方法标准对煤制气的适用性。结果表明,由于煤制气组分简单,可以采用GB/T 13610-2014分析煤制气的组成;煤制气的体积高位发热量、密度、相对密度和沃泊指数可以采用GB/T 11062-2014计算;GB/T 17747.3-2011是使用物性参数计算天然气的压缩因子,与我国目前分析习惯不相符;在对煤制气组成准确分析的基础上,推荐采用GB/T 17747.2-2011,即使用煤制气组成计算煤制气的工况压缩因子。     

Familial study of patients with hereditary hemorrhagic telangiectasia

Rendu-Osler-Weber's disease or Hereditary Hemorrhagic Telangiectasia (HTT) is an autosomal dominant hereditary clinical entity characterized by the presence of telangiectasias on skin, mucous membranes and internal organs. The incidence of hepatic, pulmonary or cerebral complications justifies an early diagnostic. A familiar study of patients previously diagnosed of HTT in our hospital was made, establishing a protocol for the identification of asymptomatic or pauci-symptomatic cases. Fourteen patients were studied: 6 with a previous diagnostic, and 8 familiar contacts. Penetrance was of 85%. Epistaxis (80%) and telangiectasias on skin were the most frequent clinical findings. The visceral lesions found were gastrointestinal (28%), hepatic (15%), urological (15%) and pulmonary (7%). All patients were included in an hepatitis B virus vaccination program. It was also made a morphological study with Werhoeff's staining of the elastic layer, that allowed to distinguish both arterial and venous alterations.