The impact of W. K. Röntgen's discovery on the use of internalizable sources of ionizing energy in diagnostic and therapeutic nuclear medicine

The early history of cathode rays, X-rays and a third kind of natural radiation from several minerals and atomic fission is described. In this way the fundamental concept of radioactivity, laws of decay and atomic models were developed. With artificial radioactive isotopes, new tailored radiopharmaceuticals could be introduced into metabolic research, medical diagnostics and therapy. Von Hevesy's concept of the dynamic state of body constituents led to examination of the locations and movements of labelled atoms and molecules as a function of time. That was the birth of nucler medicine. The principles and value at the molecular level of several specific tracer studies in research and diagnostic or therapeutic use are explained. Typically, diagnostic tests with tracer agents are non-invasive and have low radiation exposure. Competing with other diagnostic and therapeutic modalities, nuclear medicine is a speciality in its own right. But there are moves to classify it as a subspecialization of other organ-oriented clinical disciplines. That is a misunderstanding of the radiologist's role and does not answer the question: What is the best way of woking for the patient? New horizons in diagnostic modalities, biochemistry, immunology, imaging and the use of immunogenic therapeutic agents demand a continuous cooperation within interdisciplinary teams. That is as necessary with radiologic departments, participating in changed organizational structures, as with other clinical departments.     

苯氯化制对二氯苯——小试实验技术与技巧

本文报道了苯氯化制对二氯苯小试实验中氯气管道的密封、流量的计量,对二氯苯结晶处理及氯化液分析等实验技术。     

《物理教育与技艺》的框架与模式

提出革新课程《物理教育与技艺》,讨论其依据。运用结构方法总结教改实践经验,在分析处理课程要素关系的基础上,构架该课程的结构。介绍实施课程的《结合型并进式》教学模式．     

基于投影变换的多元统计过程控制与诊断模型

针对多元统计过程控制图中变异源的识别问题,给出了基于投影变换的多元过程控制和诊断模型,将原始样本数据通过投影变换,转换为相互独立的数据,然后对各独立变量分别构建控制图,从而达到控制多元过程的目的．恰当地构造变换矩阵,使转换后的样本数据的协方差矩阵为单位矩阵．由于转换后的各变量相互独立,可通过多个控制图的联合报警概率的计算,建立联合概率控制图,对过程进行整体控制;利用转换矩阵,可发现导致异常的原因．最后通过对手机摄像头聚焦度测量结果的分析将该方法进行了验证．结果表明,所提的多元过程控制方法与产控帆图的结果基本相同,并可以指示出过程变异的原因．     

新型投影式顶焦度计的结构原理及使用

顶焦度计又称对光机、查片机,可用来测量球光镜镜度、散光镜镜度、棱镜镜度以及散光轴线和光学中心点等,是眼镜片冷加工中必不可少的检测仪器。目前常用的顶焦度计有两种：一种为读数投影到影屏上,即投影式顶焦度计;另一种为目镜观察图像,即目镜观察式顶焦度计;其中投影式顶焦度计是目前普遍使用的机型。对投影式顶焦度计的结构原理及使用的阐述,为专业人员的临床使用与培养分析提供了技术参数、技术路线与技术规范。     

《汽车电子控制技术》课程教学改革与实践

针对《汽车电子控制技术》课程教学存在的问题,从优化课程教学内容和优选"三位一体"的教学形式、"合作学习"的实践教学组织形式、"基础理论+实践操作+创新能力"的课程考试形式.以及强化"双师型"师资队伍的建设等方面进行了分析和探讨.     

How to Apply Student-centered Teaching Techniques in a Large Class

It is very common to have a class of 50 or more students in Chinese schools, and teaching a foreign language effectively to a large class is really hard work. In order to change the teacher-centered teaching model into the student-centered one, Teachers should keep students＇ needs, interests, and learning styles in mind, apply several kinds of teaching techniques, organize different classroom activities and encourage, praise and appreciate both students＇ success and learning process all the time. If teachers place more responsibility in the hands of students, serve as ＂presenter or facilitator of knowledge＂ instead of ＂source of all knowledge＂, they can greatly motivate students to learn the language in a very active, cooperative and effective way. After all, people learn by doing, not only by watching and listening.     

耐盐碱水稻新组合博优938的生物学特征和高产栽培技术

介绍广西钦州市农业科学研究所选育出的感光型杂交晚籼稻新组合博优938的主要生物学特征和高产栽培技术,为推广种植杂交晚籼稻新组合博优938提供参考.     

异质经济人假设:按技术分配的哲学基础

技术所有者是纵向异质与横向异质统一的异质经济人。作为经济人的技术所有者通过个体学习、协作学习与团队学习来实现自己的纵向异质化。在纵向异质化的前提下,素质不同和能力差异成为经济人横向异质化的主要内容。因按技术分配形成的集体成员“不对称”与“选择性激励”时技术所有者产生的极大激励作用,纵向异质与横向异质统一的技术所有者内在地需要按技术分配。