新型水三相点瓶与国家基准水三相点瓶的比对

2 0 0 2年 1 1月由国际计量局组织的水三相点瓶的国际关键比对 (简称CCT -K7) ,中国计量科学研究院研制出新型结构的水三相点瓶。本文详细介绍了新型水三相点瓶 ,并将其与国家基准水三相点瓶进行了比对。同时 ,给出了比对结果。     

NIM水三相点瓶的制作

本文介绍了水三相点瓶的制作理论依据及制作过程，此外，将新制作的水三相点瓶与中国计量科学研究院保存最好的国际基准水三相点瓶进行了比对，并给出比对结果。     

水三相点瓶的国际比对介绍

本文介绍了在1994～2000年间不同国家实验室参加的由国际计量局BIPM组织的水三相点瓶的国际比对.比对结果表明,不同国家实验室所使用的水三相点瓶多数情况下在±0.1mK范围内一致.     

水三相点瓶的国际比对介绍

本文介绍了在 1 994～ 2 0 0 0年间不同国家实验室参加的由国际计量局BIPM组织的水三相点瓶的国际比对。比对结果表明 ,不同国家实验室所使用的水三相点瓶多数情况下在± 0 1mK范围内一致。     

小型水三相点瓶性能研究

首先介绍了一款小型水三相点瓶的特点和在实际工作中的应用;依据现有的国家标准,通过实验的方法,给出了这款水三相点瓶的复现性、温坪曲线、短期稳定性、长期稳定性以及与大型水三相点瓶比较等方面的数据,通过数据的分析,说明了这款装置能够应用于二级,精密及工业用铂电阻温度计,尤其是短型金属杆温度计的校准;文章最后介绍了小型水三相点瓶冻制装置在冻制过程应注意的问题以及在实际使用中的一些注意事项.     

水三相点瓶自动冻制保存装置复现性研究

介绍了型号为CIMM-TH-0230的水三相点瓶自动冻制保存装置,对该装置进行水三相点温坪复现性研究,并考核装置的各项指标。实验结果显示:该装置冻制的水三相点的温坪在48 h内变化不大于0.2 m K,复现性小于0.04 m K,稳定性优于0.5 m K,不同瓶子之间复现的温度差值不大于0.4 m K。试验数据表明该装置非常适合水三相点瓶的自动冻制、保存与复现。     

水三相点的一种制作方法

水三相点的制作和复现．是温度计量的重要工作之一。它直接关系到标准铂电阻温度计与标准水银温度计的检定质量。在水三相点瓶的冻制中，过去常常用液氮或干冰（固态二氧化碳）来制作冰套。通过水三相点瓶口将液氮或干冰缓慢倒入并从上到下逐层冻制。冻制的过程。操作复杂且要求严格；同时由于液氮制备和保存成本较高，液氮温度太低使水三相点瓶容易炸裂等原因，水三相点瓶的冻制一直是件麻烦的工作。     

巧妙冻制水三相点瓶

水三相点作为90温标的定义固定点在标准铂电阻温度计分度中起着举足轻重的作用.水三相点冻制方法很多,笔者现根据多年工作经验,介绍一种快速高效的冻制方法.[第一段]     

基于精密液体低温槽的水三相点瓶冻制方法

介绍一种使用精密液体低温槽的水三相点瓶冻制和保存方法。冻制过程简单安全,易于操作,不易损坏水三相点瓶。此种方法冻制水三相点瓶,在实际检测工作中具有较好的实用价值。     

一种快速冻制水三相点瓶的方法

水的三相点是热力学温度的唯一基准点,也是1990年国际温标(ITS-90)定义的最基本的、及其重要的固定点.水三相点的复现是通过水三相点瓶的冻制和保存来实现的,本文介绍了一种快速且实用的水三相点瓶冻制方法,并阐述了此种方法的优点.     

Comparison of Diffusion Studies of Hydrocortisone Between the Franz Cell and the Enhancer Cell

The Franz diffusion cell remains a popular method to study diffusion of transdermal drug delivery systems through membranes. Recently, VanKel Industries, Inc., (Edison, NJ) developed the “Enhancer Cell,” a new device for in vitro transdermal drug diffusion testing. The purpose of this study was to evaluate the enhancer cell for in vitro transdermal diffusion of hydrocortisone from an ointment using a synthetic membrane and a biological membrane and compare it to the traditionally employed Franz cell. The Enhancer cell utilizes existing USP dissolution equipment (USP Apparatus II). Results show a higher cumulative release from the Enhancer cell as compared to the Franz cell. The Enhancer cell demonstrated more durability and was easier to use during experimentation and after completion of the experiment no apparent change was observed in the condition of the ointment or the skin when compared to the Franz cell.     

Comparison of Diffusion Studies of Hydrocortisone Between the Franz Cell and the Enhancer Cell

Abstract

The Franz diffusion cell remains a popular method to study diffusion of transdermal drug delivery systems through membranes. Recently, VanKel Industries, Inc., (Edison, NJ) developed the “Enhancer Cell,” a new device for in vitro transdermal drug diffusion testing. The purpose of this study was to evaluate the enhancer cell for in vitro transdermal diffusion of hydrocortisone from an ointment using a synthetic membrane and a biological membrane and compare it to the traditionally employed Franz cell. The Enhancer cell utilizes existing USP dissolution equipment (USP Apparatus II). Results show a higher cumulative release from the Enhancer cell as compared to the Franz cell. The Enhancer cell demonstrated more durability and was easier to use during experimentation and after completion of the experiment no apparent change was observed in the condition of the ointment or the skin when compared to the Franz cell.     

The Insertion Mechanism of a Living Cell Determined by the Stress Segmentation Effect of the Cell Membrane during the Tip–Cell Interaction

Atomic force microscopy probes are proved to be powerful tools to measure and manipulate the individual cell, providing potential applications for the controlled drug/protein delivery. However, the measured insertion efficiency varies dramatically from 20 to 80%, in some cases, the nanotip can never penetrate the cell membrane no matter how much force is applied to it. Thus, the insertion mechanism of a living cell during the tip–cell interaction must be thoroughly investigated before this technology comes into practical applications. In this work, a multistructural cell model is established to study the tip–membrane interaction. The simulation results show that the stress of the cell membrane can be divided into two stages by the stress segmentation point S. After point S, the stress of the cell membrane increases slightly and most of the indentation force is allocated to the cytoskeleton. This phenomenon is called “stress segmentation effect of the cell membrane,” which confirms the hypothesis based on the experimental studies. Moreover, according to the experimental and numerical studies, the hypothesis of the stress segmentation effect also explains the reason that modifying the cell membrane or using the manmade sharpened nanotip can increase the insertion efficiency.     

光电致变色器件的研究进展

光电致变色器件将染料敏化纳米晶太阳电池与电致变色电极巧妙地结合在一起,构成自供电的电致变色窗,通过对太阳光谱的智能调控达到建筑节能和装饰的效果.与电致变色智能窗相比,无需电源和导线连接,解决了其结构和安装的经济性.主要论述了光电致变色器件的结构和最新研究进展,并对其应用前景进行了展望.     

Enhancing Cell therapies from the Outside In: Cell Surface Engineering Using Synthetic Nanomaterials

Therapeutic treatments based on the injection of living cells are in clinical use and preclinical development for diseases ranging from cancer to cardiovascular disease to diabetes. To enhance the function of therapeutic cells, a variety of chemical and materials science strategies are being developed that engineer the surface of therapeutic cells with new molecules, artificial receptors, and multifunctional nanomaterials, synthetically endowing donor cells with new properties and functions. These approaches offer a powerful complement to traditional genetic engineering strategies for enhancing the function of living cells.     

Electromechanical Nanogenerator–Cell Interaction Modulates Cell Activity

Noninvasive methods for in situ electrical stimulation of human cells open new frontiers to future bioelectronic therapies, where controlled electrical impulses could replace the use of chemical drugs for disease treatment. Here, this study demonstrates that the interaction of living cells with piezoelectric nanogenerators (NGs) induces a local electric field that self‐stimulates and modulates their cell activity, without applying an additional chemical or physical external stimulation. When cells are cultured on top of the NGs, based on 2D ZnO nanosheets, the electromechanical NG–cell interactions stimulate the motility of macrophages and trigger the opening of ion channels present in the plasma membrane of osteoblast‐like cells (Saos‐2) inducing intracellular calcium transients. In addition, excellent cell viability, proliferation, and differentiation are validated. This in situ cell‐scale electrical stimulation of osteoblast‐like cells can be extrapolated to other excitable cells such as neurons or muscle cells, paving the way for future bioelectronic medicines based on cell‐targeted electrical impulses.     

燃料电池用磺化聚醚醚酮薄膜的研究进展

概述了近几年来燃料电池用磺化聚醚醚酮(SPEEK)质子交换膜的研究进展,分别从聚醚醚酮(PEEK)磺化制备SPEEK、SPEEK薄膜的制备和改性SPEEK薄膜等几个方面总结了SPEEK质子交换膜的研究结果,并分析展望了研究工作的发展趋势.     

Overlap-Based Cell Tracker

In order to facilitate the extraction of quantitative data from live cell image sets, automated image analysis methods are needed. This paper presents an introduction to the general principle of an overlap cell tracking software developed by the National Institute of Standards and Technology (NIST). This cell tracker has the ability to track cells across a set of time lapse images acquired at high rates based on the amount of overlap between cellular regions in consecutive frames. It is designed to be highly flexible, requires little user parameterization, and has a fast execution time.