Equipment for Multiple Projects: Cisorp Water Sorption Analyser.

CI水吸附分析仪微天平的目的是支持一些正在资助的研究活动，并在曼彻斯特大学建筑科学研究小组及其更广泛的相关网络(爱丁堡大学材料科学与工程中心；布里斯托尔大学界面分析中心)内开展广泛的进一步工作。微量天平将为目前资助的石灰砂浆系统工作提供大量投入，不仅可以研究碳化速率，还可以研究这些材料的水化速率。申请人最近发表了一个新的动力学定律，该定律表明，烧成的粘土陶瓷对大气水分的化学吸附引起的质量增加和相关的膨胀应变都与(时间)1/4成正比。这一渐进的化学驱动过程表明，烧成的粘土发生了非常显著的再羟化作用，这一过程是如此缓慢，以至于肯定会在所有实际历史时间尺度上持续下去。事实上，我们已经在2000年前的陶瓷中发现了剩余的反应性。反应的极其缓慢的进展似乎是这些材料的基础，而且肯定具有重大的科学意义。到目前为止，这种反应的潜在机制还远远不清楚。正是利用这一(时间)1/4定律作为考古年代测定的方法，形成了拟议的微天平工作的核心。我们已经证明，通过测量陶瓷制品在重新加热之前的质量，并将其与重新加热后同一样品的后续质量增量进行比较，可以估计陶瓷制品的年龄。对质量增益的测量提供了校准数据，该数据定义了该特定材料的质量增益率随时间的变化。因此，可以通过外推数据来确定样品的年龄，以确定达到测量的长期质量的时间。由于该方法是自校准的，消除了烧成温度、矿物学、成分等差异的影响。这项工作需要在温度和相对湿度的精确控制条件下对陶瓷样品进行极高精度的称重。同时，这种测量技术是深入了解潜在的化学吸附机制的有力手段。此外，该仪器将使各种不同的研究成为可能，否则传统测量技术将无法获得这些研究。这些研究包括研究玻璃中的化学吸附反应(特别是在污染大气中)，以及研究天然建筑石材的降解机制--在这种情况下，重点是城市大气污染物。

The purpose of the CI water sorption analyser microbalance is to support a number of ongoing funded research activities and to enable a wide range of further work within the Construction Science Research Group at the University of Manchester and its wider associated network (Centre for Materials Science and Engineering, The University of Edinburgh; the Interface Analysis Centre, University of Bristol). The microbalance will have substantial input into currently funded work on lime mortar systems and will enable studies not only of carbonation rates but also of hydration rates in these materials. The applicants recently published a new kinetic law which shows that the mass gain and associated expansive strain caused by the chemisorption of atmospheric moisture by fired clay ceramics are both proportional to (time)1/4. This progressive chemically driven process indicates a very remarkable rehydroxylation of the fired clay which is so slow that it continues certainly over all practical historical timescales. Indeed we have found residual reactivity in 2000 year old ceramic. The extremely slow progress of the reaction appears to be fundamental to these materials and must be scientifically significant. The underlying mechanisms of this reaction are as yet far from understood. It is the exploitation of this (time)1/4 law as a method of archaeological dating that forms the core of the proposed microbalance work. We have shown that it is possible to estimate the age of a ceramic artefact by measuring its mass prior to reheating and comparing this with the subsequent mass gain from the same sample following reheating. Measurement of the mass gain provides calibration data that define the rate of mass gain with time for that particular material. The specimen's age may therefore be established by extrapolation of the data to determine the time at which the measured long-term mass would be attained. Since the method is self-calibrating, the effects of differences in firing temperature, mineralogy, composition etc are eliminated. This work requires the extremely high-accuracy weighing of ceramic samples under precisely controlled conditions of temperature and relative humidity. In parallel with this, such a measurement technique is a powerful means of gaining insight into the underlying chemisorptive mechanisms. Further, the instrument will enable a diverse range of studies which would otherwise be inaccessible with conventional measurement techniques. These include the investigation of chemisorption reactions in glasses (particularly in polluting atmospheres) and investigations of the degradation mechanisms in natural building stones - in this case with a focus on urban atmospheric pollutants.