质量控制样品BOD5的速算公式

BOD5质量控制样品监测起来麻烦、费时,而利用BOD5质量控制样品的速算公式,只要准确测得BOD5质量控制样品的COD值,就可以速算出BOD5质量控制样品的BOD5值。     

以用户搜索行为为导向的检索课教学T检验分析及效果评价

C.C.Kuhlthau以建构主义理论为基础提出了著名的信息搜索六步骤(被称作Kuhlthau模式信息搜索行为模型)。文章基于Kuhlthau搜索行为模型,设计出了以用户搜索行为为导向的信息检索课教学模式,并付诸教学实践;根据设计实施的检索课教学实践中收集的数据和信息,利用SPSS统计软件对以用户搜索行为为导向的信息检索课教学的实施效果进行配对样本T检验分析和评价。     

Determining The Presence of Photocatalytic Titanium White Pigments via Embedded Paint Sample Staining: A Proof of Principle

ABSTRACT

Twentieth century paints often contain titanium dioxide and zinc oxide based white pigments that can range from photostable to highly photocatalytic. Photocatalytic pigments can cause the degradation of paint upon UV exposure, whereas photostable pigments may be benign or can protect paintings from degradation. Hence, knowing whether or not a pigment is photocatalytic is of high importance for risk assessment and the subsequent decision making process concerning storage and exposure conditions of objects. Here we present a proof of principle, focused on titanium white paints, for an easy-to-use and low-tech application of a commercial photocatalytic activity indicator ink (PAII) on embedded paint samples or cross sections. This test determines, qualitatively, if a photocatalytic pigment is present in a white paint sample. The PAII paint sample staining application shows an obvious color change, within five minutes of UV irradiation, for paint samples containing photocatalytic pigments. A microscope with a camera and a UV source are the only necessary equipment for the application of this method. A quantitative image processing protocol is also proposed as an extension of the staining method by applying open source software analysis to measure the color change using photographs. The test was evaluated on reference paints with well-characterized pigments and applied on samples from modern paintings by Piet Mondriaan, Robert Ryman, and Lucebert, indicating the presence of harmful photocatalytic pigments in these cases. The novel application of a commercial ink on paint samples offers a simple test, not just for assessment of photocatalytic activity of titanium white pigments, but which may in future be applied for the detection of photoactive forms of zinc white and other potentially harmful semiconductor pigments in art objects.     

假彩色合成和精度评价方法对遥感影像分类精度的影响

文章介绍了假彩色合成分量选择的方法、精度评价中样本大小的计算及抽样方式对分类精度的影响。对分类精度的提高具有借鉴意义。     

Science Letters:Detection of Catabacter hongkongensis in polluted European water samples

The Catabacteriaceae is a new bacterial family with a unique member: Catabacter hongkongensis is a strictly anaerobic, non-sporulating, Gram-positive coccobacillus that is phylogenetically related to some clostridial clusters. Little is known of its epidemiology and environmental distribution, but the inclusion of its 16S rRNA gene sequence in GenBank has allowed it to be detected qualitatively. As a first approach for prospective surveys, a real-time polymerase chain reaction (PCR) procedure to identify C. hongkongensis has been developed. The presence of Catabacteriaceae in 29 water bodies subjected to possible human or animal impact has been investigated. Four of them were positive. The results confirm that highly polluted water can contain C. hongkongensis.     

基于模糊知识获取的锅炉电控设备故障诊断方法及其应用

基于模糊诊断的知识获取了 10T以下锅炉电控设备运行过程中的故障事例的样本 ,并通过模糊逻辑诊断方法得出诊断结论。同时 ,还对锅炉电控设备可靠性工作的思维方法进行了探讨     

人力资源开发的培训评估模型及其修正与完善

本文对国际上流行甚广的柯克帕特里克"四级评估模型"以及对之起到重要修正和完善作用的"五级评估模型"及CIRO和CIPP培训评估模型进行了介绍和评论,指出了各个评估模型的优缺点。以期对我国企业人力资源开发进程中的员工培训评估工作产生有益的启迪和借鉴作用。     

固相萃取技术及其应用

固相萃取是近年来发展较快的样品预处理技术.主要阐述了固相萃取技术的基本原理及方法,简述了固相萃取技术的发展状况及应用.     

建立评分误差控制体系,提高音乐专业考试信度

本文介绍了音乐专业考试的评分办法；研究了准确度的评价、稳定性评价的方法；分析了评分误差曲线。