Acquisition of a Powder X-ray Diffractometer for Environmental and Materials Research at UC Merced

购买粉末X射线衍射仪(X射线衍射仪)系统满足了加州大学默塞德分校的各种研究和教学需求，这是加州大学系统的第10个新校区，于2005年秋季正式向本科生和研究生开放。粉末X射线衍射仪是正在进行的环境和材料研究的重要工具，也是扩展我们的跨学科材料科学、工程和化学科学计划的关键工具。我们正在购买一种基本的、高质量的仪器，具有自动化功能，可以根据不同的应用轻松重新配置，以服务于一系列用户和研究需求。该仪器的特点包括带有铜X射线管的固态X射线发生器，theta-theta测角仪(用于固定样品、移动源和探测器)，低背景的快速固态探测器，以及用于空气敏感样品和研究随温度变化的相变的温度控制的惰性气体样品室附件(-193℃至+450℃)。X射线衍射仪将作为我们现有的成像和显微镜设施的一部分向用户开放，这是第一个集中式校园充值设施，并由一名全职实验室经理提供支持，他将负责仪器监督和用户培训。它将支持教师、研究生和本科生的研究，并将用于环境化学、仪器/分析方法、土壤化学、材料科学和材料工程等课程。加州大学默塞德分校目前和计划支持的研究包括：环境中污染物的化学和迁移；土壤、沉积环境和工程系统中地质颗粒的环境化学和矿物学；大气和环境中的团聚体和纳米颗粒；天然生物材料的特性；半导体纳米颗粒的合成、表征、结构和特性。主要应用包括定性和定量相识别、非晶态/晶态表征、晶型识别、杂质分析以及与温度和气氛相关的相变研究。该仪器将对加州大学默塞德分校为加州大学默塞德分校服务于加州中央山谷南部快速增长的人口的使命产生广泛影响，该地区以西班牙裔为主，移民和第一代人口较多，在高等教育中历来代表不足。

The acquisition of a powder X-ray diffractometer (XRD) system serves a variety of research and teaching needs at UC Merced, the new 10th campus in the UC system, which officially opened its doors for undergraduate and graduate students in Fall 2005. Powder XRD is an essential tool for ongoing environmental and materials research, and a critical instrument for the expansion of our interdisciplinary materials science and engineering and chemical sciences programs. We are purchasing a basic, high quality instrument with automated capabilities that can be easily reconfigured for different applications to serve a range of users and research demands. Features of the instrument include a solid-state X-ray generator with Cu X-ray tube, theta-theta goniometer (for a stationary sample, moving source and detector), fast solid-state detector with low background, and a temperature-controlled, inert gas sample chamber attachment (-193 C to +450 C) for air-sensitive samples and investigation of temperature-dependent phase changes. The XRD instrumentation will be openly available to users as part of our existing Imaging and Microscopy Facility, the first centralized campus recharge facility, and supported by a full-time laboratory manager who will be responsible for instrument oversight and user training. It will support faculty, graduate, and undergraduate research, and it will be used in courses such as environmental chemistry, instrumental/analytical methods, soil chemistry, materials science, and materials engineering. Current and planned research that will be supported at UC Merced includes: the chemistry and mobility of contaminants in the environment; environmental chemistry and mineralogy of geoparticles in soils, sedimentary environments, and engineered systems; atmospheric and environmental agglomerates and nanoparticles; properties of natural biomaterials; synthesis, characterization, structure, and properties of semiconductor nanoparticles. Main applications include qualitative and quantitative phase identification, amorphous/crystalline characterization, polymorph discrimination, impurity analysis, and temperature- and atmosphere-dependent phase transformation studies. The instrumentation will have a broad impact in contributing to UC Merced's mission to serve the rapidly growing population of the southern Central Valley of California, which is dominantly Hispanic, has a high immigrant and first-generation population, and is historically underrepresented in higher education.