大学物理实验是对高校一年级学生进行科学实验基本训练的一门重要的实践性基础课程,它是对学生科学素养和动手能力培养的重要教学环节.在实验教学过程中充分发挥学生的主动性、大胆性,引导学生分析实验中出现的问题和寻求解决问题的办法,从而培养学生的实践动手能力以及分析问题和解决问题的能力.通过对实验教学改革的探索,学生的实验动手能力、分析问题和解决问题的能力都得到了提高,同时,也培养了学生的创新意识.

This paper discusses a new in vivo XRF bone lead detection system and introduces how to study the radioactive activity, exposure rate, absorb doses, equivalent dose and effective dose of the system using the long life source of 238Pu and analyzes the dose safety about the system.

Raman spectroscopy with optical fibre probes, a kind of vibrational spectroscopy providing detailed information about molecular composition and structure of tissues. The great appeal of Raman spectroscopy lies in its potential for in vivo applications and its ability to therefore direct real-time therapeutic intervention. Objective: The purpose of this study was to discuss optical fibre probes for in vivo Raman Spectroscopy and its clinical implementation. Methods: Important progress of technology and application in medicine were introduced and summarized. Results: Raman spectroscopy equipment with optical fibre probes, meets important prerequisites for the development of tools for in vivo real time tissue analysis, during clinical procedures such as endoscope, biopsy, and surgery. Conclusion: In vivo diagnostic tools are much needed in many fields of medicine to take the sometimes unavoidable guesswork out of current clinical procedures, to avoid long delays caused by ex vivo evaluation of patient material, or to simply replace current invasive methods by noninvasive or less invasive techniques. In vivo Raman spectroscopy may fulfil a role in all of these fields.

作者结合亲身教学经历,分析了当前农业类少学时大学物理教学所面临的突出问题,并针对这些问题提出了相应的教学改革措施。

To improve instruction quality and cultivate innovative talents,the paper studies the instruction and practice of basic course of college science in higher agricultural and forestry universities under new training plan,including:updating teaching ideas,handpicking course content,exploring 3I instruction model,integrating style of agricultural and forestry universities.

以华中农业大学2005—2007级所有修习过大学物理课程的学生为总样本,通过分层随机抽样,采用自编"高等农林院校大学物理课程学生问卷",进行问卷调查.经过差异性分析,得到调查结果:(1)不同年级学生在教师教学上存在极显著性差异,而在教学资源、教学评价、学习心得上并不存在差异;(2)不同性别学生在学习心得上存在显著性差异,而在其他维度上不存在差异;(3)不同专业学生对教学评价上存在显著性差异,在其他各维度上都存在极显著性差异;(4)不同省份的学生在学习心得上存在显著性差异,而在其他维度上不存在显著性差异.

Cumulative exposure is more predictive of chronic toxicity than recent exposure that is what blood levels mostly reflect. Bone lead levels have served as a cumulative dosimeter of lead exposure for many years because of the long residence time of Pb in bone, and it has been more than 30 years since in vivo x-ray fluorescence (XRF) was first made. This paper summarizes the world-wide advances in the measurement systems with ~(57)Co, ~(125)I and ~(109)Cd excited re-spectively.

Lead is a leading environmental toxicant and Lead exposure has effects on many systems. Bone lead measured in vivo, has been shown to reflect cumulative lead exposure. Objective: To introduce and study in vivo XRF Measurements of Lead in Bone. Methods: Important progress and technology were summarized and introduced. Results: In vivo XRF is a safe and effective tool, which has enabled skeletal lead concentration measurement. X-ray spectrometry in vivo has contributed to the understanding of long-term human lead metabolism in ways that would not otherwise have happened. Conclusion: Efforts to introduce further improvements to the XRF technique are ongoing in order to lower its measurement uncertainty and enhance reproducibility. This may become especially important as the method becomes more widely used in the study of non-occupationally exposed populations, whose bone lead concentrations are generally quite low and thus comparable with the MDL of the standard XRF technique.

The paper discusses the harm of lead in the body,the shortage of blood lead,the importance of bone lead as a new biomarker.In vivo XRF measurements of lead in bone were first made in the early 1970s.these systems have been divided into 57Co excited K,125I or polarized excited L,109Cd excited K.

The paper describes a general method for analysis of time courses of transmembrane voltage induced by time-varying electric fields. Using this method, a response to time-varying fields can be studied. We apply it to different field shapes used for electroporation: rectangular pulses and trains pulses. Using the described method, the course of induced transmembrane voltage is investigated for each selected pulse shape. All the studies are performed at different pulse durations, For all the pulse shapes investigated, this slows down the process of transmembrane voltage inducement. Thus, longer pulses have to be used to attain the desired voltage amplitude, as the influence of the fast, shortlived phenomena on the induced voltage is diminished.

A review with 22 references is given on in vivo XRF measurements of lead in bone.The three systems(57Co excited K,125I or polarized excited L,109Cd excited K)were compared,109Cd excited K X-ray fluorescence has been most widely adopted.

Food safety has been an important problem that people concern much. As a convenient, quick, efficient measuring technique, supersonic wave has been applied widely in measuring food safety. This paper introduces the principle of supersonic wave, describes the latest development of supersonic wave in measuring food safety and points out its unique advantage and bright future in measuring fruit and vegetable products, meat products, milk products and other aspects.

有报道,兔肉内矿物质总量是1.779%,其中磷的含量为0.579%[1];成年动物体中含磷量按新鲜组织计算为0.60%～0.75%,按干组织计算为1.9%～2.5%[2].传统的家兔体内磷含量测量方法是通过宰杀后取样,用原子吸收光谱法(AAS)和离子质谱仪(SIMS)测量以及用反应堆、加速器产生的中子源辐照样品进行活化法分析测量.这些方法都是离体测量的,且是动物器官取样.

The physics demonstration experiments have already played an important role in the college physical teaching and now they are indispensable to the college physics teaching.The physics demonstration experiments not only can help students build up physical concepts,comprehend physical regulations and master physical knowledge,but also is greatly helpful to cultivate a student's creative ability.With the combination of real objects and computer simulation in demonstration experiments,effects of physics teaching are increased in agricultural and forestry universities.

Through the introduction of history of bone lead testing,comparison of various apparatus lead content and the latest situation of research on In vivo XRF testing bone lead.This paper discussed the significance of In vivo XRF non-Invasive testing bone lead content.

The in vivo X-ray fluorescence in measuring human bone lead is a non-invasive testing approach.Human bone lead can reflect the long accumulated effect on human,while blood lead just illuminates the state that man touches lead recently.This paper showes a general view of home and abroad researches about in vivo X-ray fluorescence measuring bone lead and discusses the significance of this approach.

A review with 31 references is given on the harm of lead in the body,the shortage of blood lead leve,the importance of bone lead and the progress of XRF.It suggested the bone lead should be a new biological marker of lead dose.

The development of NIR technology and its application to the identification of stored-grain insects are presented briefly. Through the analysis of the current near infrared spectoscopies for identifying stored-grain insects in the world, a new research idea of identifying stored-grain insects by combining the NIR technology with the image recognition is proposed.

基于高等农林院校的大学物理学教学的特点,以电子和网络教材为突破,以教学诊断系统为补充和拓展,构建了高等农林院校大学物理立体化教材体系,在实践中实现了教学效益的最大化.

本文按照现代物理实验教学的层次性、自主性和开放性的要求,指出优化整合物理实验的优点,提出确保优化整合物理实验顺利实施的措施.优化整合物理实验力求改变传统物理实验命题过窄的弊端,能让学生在更宽的物理实验命题范围内自由组合实验,旨在引导学生思考,发挥学生的个性和创新精神,全面培养学生的素质和能力.