Changes of Surface Properties of Yeast Cell Wall Under Exposure of Electromagnetic Field (40.68 MHz) and Action of Nystatin

Summary Changes of the surface properties were studied in the cell wall of the yeast Saccharomyces cerevisiae Y-517 under influence of the electromagnetic field (EMF) (40.68 MHz) and lethal doses of the fungicidal antibiotic nystatin (10 μg/10⁶ cells). Atomic force microscopy was used to study surface topography and visco-elastic properties of the cell walls. Surface carbohydrates were detected by lectins marked with gold with the help of the scanning electron microscope. Additional polysaccharide layer appeared over cell surface after EMF exposure. We suggest that electromagnetic fields resulted in the change of the cell surface, and, accordingly, the sensitivity of organisms to the antifungal antibiotics.     

原油对草原植被的影响

为了定量说明落地原油对大庆地区草原植被的影响，选择了四种植物群落进行浇原油试验，浇油厚度为0．2、0．4、0．8cm，浇油时间为秋、春、夏。试验结果表明原油对植物个体的影响因原油量、季节和植物种类的不同而不同，随原油量的增加影响增大。     

气田含甲醇污水处理问题探讨

气田含甲醇污水处理目前国内尚没有工程实例。结合陕甘宁中部气田含甲醇污水处理设计，对气田含甲醇污水中甲醇的再生工艺方法、厂址确定、净化后含甲醇污水的排放、生产安全及卫生等问题进行了较详细的讨论。     

气田开发对水土流失的影响预测──以陕甘宁盆地中部气田开发为例

结合大量的实际调查资料，筛选出影响水土流失的因子，建立了预测水土流失的灰色状态模型；并以此分析了气田开发对水土流失的影响，最后作出了影响预测，并提出了相应的措施与对策。     

油田放射性测井对人体的损伤及防护对策

在油田放射性测井过程中，对人体产生损伤的决定因素是人体对辐射的敏感程度，所受辐射剂量的大小及受照条件。通过对２９９人的个人剂量监测数据进行分析，指出放射性测井中主要的损伤是长期小剂量慢性效应，并针对性地提出了相应的防护措施。     

云南大理地区地震中长期前兆现象分析

通过对大理地区多年来地磁场、重力场、地壳形变和地下水等地震前兆因素变化趋势的分析，指出大理地区是云南省未来１０年内发生强震危险性最大的区域之一。     

四川原煤及其废渣与制品放射性的测试分析

本文介绍了四川原煤及其废渣与制品的γ辐射剂量率、附加γ辐射人均年有效剂量量。同时,用低本底Ge(Li)多道γ能谱仪测定了原煤、矸粉与矸砖,煤渣与煤渣砖、粉煤灰及粘土砖等样品中的天然放射性核素~(238)U,~(232)Th,~(226)Ra,~(40)K的比活度。经比较和研究,找出了这些物质的放射性水平及它们彼此之间的规律。     

Does salt marsh fertilization enhance shellfish production? An application of flow analysis

The method of flow analysis, which is similar to economic input-output analysis, is presented as a means of making flow models of ecological systems more useful to environmental managers. This paper considers as an illustration the extent to which nitrogen fertilizer added toSpartina salt marsh sediments can enhance shellfish growth. Nitrogen flow models of both the Barataria Bay salt marsh complex of coastal Louisiana and the Sippewissett Marsh of western Cape Cod are analyzed. The analysis shows the transfer of added nitrogen to shellfish growth viaSpartina growth, decomposition, and detrital feeding to be considerably less efficient than its transfer toSpartina growth itself. These results are similar for both marsh systems, despite their great physical differences and despite the inclusion of considerably more microbial processing of nitrogen in the Barataria Bay model than in the Sippewissett models. The results suggest that the most efficient mechanism by which added nitrogen could enhance shellfish growth in salt marshes may have to bypass the route through theSpartina life cycle.     

Influence of DC electric and magnetic fields on silicon solar cells/modules

ABSTRACT

In this study, the impact of DC electric and magnetic fields on the output power, open-circuit voltage, and photocurrent density of a silicon photovoltaic (PV) cell/module is assessed. In this regard, the influence of DC electric and magnetic fields is first evaluated in theory by formulating and discussing related basis and concepts. Then, experimental measurements and data obtained from two different sets of experiments are given that verify theoretical results. In theory and practice, it is shown that depending on the direction of a DC electric field applied to a silicon PV cell/module, it causes an increase or reduction in the output power and open-circuit voltage of the PV cell/module. In detail, when the DC electric field points in the direction of the junction electric field of the PV cell(s), the output power and open-circuit voltage of the silicon PV cell/module increase, otherwise the output power and open-circuit voltage decrease. Regarding the magnetic field, it is proved that depending on the direction of a DC magnetic field applied to a silicon PV cell/module, different effects are observed. In detail, when the DC magnetic field points along the junction electric field of the PV cell(s), it has no effect on the output power and open-circuit voltage of the silicon PV cell/module. But, the output power and open-circuit voltage of the silicon PV cell/module decrease when the DC magnetic field points in the other directions. Moreover, the reduction in the output power and open-circuit voltage reaches its peak when the DC magnetic field is applied in the direction perpendicular to the junction electric field.     

除尘器三维流场自动检测系统及其应用

介绍了以五孔球形探针为主的除尘器流场自动检测系统的研制过程。同时,应用该系统对两种旋风除尘器进行了测定。测定结果表明,该系统完全满足除尘器三维流场的测定要求。