Acquisition of a Low Vacuum Scanning Electron Microscope

正在申请资金购买具有数字图像存储和输出能力的低真空扫描电子显微镜(扫描电子显微镜)。建议购买的JEOL JSM-5410LV型号，在高真空模式下可以达到4 nm的分辨率，在低真空模式下可以达到5.5 nm的分辨率。加速电压范围从0.5千伏到30千伏，放大倍数可以高达200,000倍，也可以低至15倍。在低真空和高真空模式下，样品腔压力分别在270Pa2 Torr到7×10-4Pa5×10-6Torr之间变化。具有这些规格的扫描电子显微镜对植物学研究有许多优势，但主要的优点是，在低真空模式下，可以直接观察植物组织，而不需要化学固定、脱水或金属涂层。这不仅节省了准备时间，还将更准确地表示要观察的精致标本，在某些情况下，将不再需要更改或实际销毁具有独特特征的标本，例如古植物材料。此外，标本的数字图像可以电子存储，并以TIFF文件的形式添加到数据库中的植物标本记录。高真空模式也可用于提供可与目前市场上使用钨电子源的常规扫描电子显微镜相媲美的高分辨率成像。扫描电子显微镜是植物系统形态研究不可缺少的工具。纽约植物园(NYBG)要求资金购买新的扫描电子显微镜，以取代目前使用了10年的仪器，它的使用寿命即将结束。扫描电子显微镜在NYBG用于研究花粉粒、孢子和各种植物组织，如表皮、维管分子和花的成分。这样的调查提供了微形态数据，这对花园的工作人员和研究生的研究是必不可少的。该仪器还将用于鉴定不同的植物样本，作为古民族植物学调查的关键组成部分，并向公众和某些政府机构提供基本信息。该提案包括使用扫描电子显微镜对NYBG进行的研究活动和身份鉴定服务的详细描述。来自之前NSF支持的结果：D.L.Lentz在过去五年中没有收到NSF的拨款。

Funds are being requested for the acquisition of a low vacuum scanning electron microscope (SEM) with a digital image storage and output capability. The model proposed for purchase, a JEOL JSM-5410LV, can achieve a resolution of 4 nm in the high vacuum mode and 5.5 nm in the low vacuum mode. Accelerating voltages range from 0.5 to 30 kV and magnifications can be as high as 200,000X or as low as 15X. Specimen chamber pressures vary from 270 Pa (2 Torr) to 7 X 10-4 Pa (5 X 10-6 Torr) in the low and high vacuum modes, respectively. A SEM with these specifications has many advantages for botanical research, but the main asset is that plant tissues can be observed directly without the need for chemical fixation, dehydration or metal coating in the low vacuum mode. This will not only represent a savings in preparation time, but also will provide more accurate representations of delicate specimens to be observed and in some cases will obviate the need to alter or actually destroy specimens that are unique in character, e.g., paleobotanical material. Furthermore, digital images of specimens can be stored electronically and added as TIFF files to databased botanical specimen records. The high vacuum mode also can be used to provide high resolution imaging comparable to currently-marketed, conventional SEM's that employ a tungsten electron source. The SEM is an indispensable instrument for systematic and morphologic plant research. The New York Botanical Garden (NYBG) requests funds to purchase a new SEM to replace the currently used 10-year-old instrument, which is nearing the end of its useful life. The SEM is used at the NYBG to investigate pollen grains, spores and various plant tissues such as epidermises, vascular elements and floral components. Such investigations provide micromorphological data that are essential to the research of the Garden's staff and graduate students. The instrument also will be used for the identification of varying plant samples as a key compo nent of paleoethnobotanical investigations and for the purpose of supplying essential information to the public and certain government agencies. The proposal includes detailed descriptions of research activities and identification services performed at the NYBG using the SEM. Results from Prior NSF Support: D. L. Lentz has not received an NSF grant within the last five years.