地面地震CT在浅层勘探中的应用

在地表面沿研究区域的四周布置激发点和检波器 ,进行人工地震观测记录。地震能量由激发点到达接收点 ,利用直达波、反射波和折射波等多震相 ,进行 CT反演 ,得到波速地震 CT图像。该图像给出浅层波速横向分布 ,反映了覆盖层分区及基底岩性特点与构造分布。该方法应用于某工程场地的浅层勘探中 ,所得波速 CT图像与地质露头及开挖相吻合。该方法将地震 CT技术从钻孔和巷道中解放出来。     

ICP-OES法测定地球化学样品中的铁

试样采用HCL、HNO3分解,制成2~3%王水溶液。在最佳条件下,用ICP-OES法测定地球化学样品中铁含量,测定范围为0.10~20%。方法简便快速,精密度和准确度能满足分析要求,符合地质矿产实验室测试质量管理规范(区域地球化学普查样品化学成分分析)。适用于地球化学调查样品批量样品中铁的测定,已应用于实际工作中,结果满意。     

重金属暴露与肾功能的关联性研究：基于代谢综合征人群的横断面研究证据

探索代谢综合征人群中重金属暴露与肾功能的相关性,为特定人群中慢性肾脏病的诊治提供新思路。基于2011—2018年美国健康与营养调查数据,纳入2 474名代谢综合征患者作为研究对象;探讨四种血液金属元素(包括镉、铅、硒、锰)对肾功能的影响。肾功能主要通过慢性肾病(CKD)、估计的肾小球滤过率(eGFR),尿微量白蛋白肌酐比(UACR)和尿酸(UA)评估。通过加权多因素Logistic回归模型及线性回归模型分析血液中金属元素水平与肾功能的关系。进一步按照年龄、性别、体质量指数(BMI)、是否患高血压、糖尿病及血脂异常进行亚组分析。研究发现血液中镉、铅水平与CKD的发生呈正相关,与eGFR呈现负相关。血硒与CKD的发生存在负向关联,而血锰与eGFR水平存在正相关(P<0.05)。而亚组分析结果显示,女性及老年代谢综合征患者对于金属暴露的效应更为敏感。代谢综合征人群中重金属暴露与肾功能存在关联,铅、镉暴露可能会导致肾功能受损,而硒、锰暴露则可能会起到一定的保护作用。     

Radiological mapping of Kelantan,Malaysia, using terrestrial radiation dose rate

Measurements of the environmental terrestrial gamma radiation dose rate (TGRD) in each district of Kelantan state, Malaysia, were carried out using a portable hand-held radiation survey meter and global positioning system. The measurements were done based on geology and soil types of the area. The mean TGRD was found to be 209 nGy h^–1. Few areas of relatively enhanced activity were observed in Pasir Mas, Tanah Merah and Jeli districts, which have a mean TGRD between 300 and 500 nGy h^–1. An isodose map of the area was produced using ArcGIS software version 9.3.     

敏感性问题调查方法的探讨

本文探讨了敏感性问题的四种调查方法，并结合实例进行比较，最后，对各种方法的优劣和应用范围提出作者的见解     

沥青路面破损图像自动检测系统设计

介绍了由承载车、计算机、路面破损图像采集子系统、路面破损定位子系统、路面破损图像处理子系统等组成的路面破损自动检测实验系统,根据理论分析确定了摄像机的安装位置参数。利用网络通信技术,实现了双CCD摄像机同步采集路面图像,同时对路面破损图像的几何畸变进行了校正。实验结果表明,该系统对典型的路面破损状态可以准确的检测识别。     

Indoor radon survey in dwellings of some regions in Yemen

Indoor radon survey in a total of 241 dwellings, distributed in some regions of Yemen was performed, using CR-39 based radon monitors. The objective of this radon survey is to get representative indoor radon data of three regions, namely Dhamar, Taiz and Hodeidah, situated at different altitudes above sea level. The radon concentrations varied from 3 to 270 Bqm⁻³ with an average of 42 Bqm⁻³. It was found that the average radon concentration in the surveyed areas increases with altitudes. The highest average radon concentration of 59 Bqm⁻³ was found in Dhamar city while the lowest average concentration of 8 Bqm⁻³ was found in Hodeidah city.     

Sociocultural Meanings of Nanotechnology: Research Methodologies

This article identifies six social-science research methodologies that will be useful for charting the sociocultural meaning of nanotechnology: web-based questionnaires, vignette experiments, analysis of web linkages, recommender systems, quantitative content analysis, and qualitative textual analysis. Data from a range of sources are used to illustrate how the methods can delineate the intellectual content and institutional structure of the emerging nanotechnology culture. Such methods will make it possible in future to test hypotheses such as that there are two competing definitions of nanotechnology – the technical-scientific and the science-fiction – that are influencing public perceptions by different routes and in different directions.     

On some optimum problems of vibration theory

Some optimum problems of vibration theory and the variational approach to their solution are discussed. The results of construction of optimum solutions obtained by means of necessary conditions of the calculus of variations are presented.     

化学教学论实验课程教学评价工具的研究

为建立完整的化学教学论实验教学评价工具，在已构建的理论框架基础上，进行了2轮实证数据的采集和分析，对评价工具进行了修改和完善。第1轮调查对象是S大学102位化学专业师范生，针对评价框架中的一级指标和二级指标进行修改和删减，共计12处。基于修改后的评价框架，形成第2份调查问卷。第2轮调查对象是14所高校的15位专家，针对理论框架、评价框架中的各级指标和评价标准进行相应的删减、内涵及表述修改、项目补增等，共计30处。最后，形成了一个包含5个一级指标、24个二级指标和37个评价标准且全面具体、科学合理的化学教学论实验课程教学评价工具。