Study on the dominant species of Pteropoda in East China Sea

1 INTRODUCTION Pteropoda is a group of marine pelagic mol- lusks, which belongs to Opisthobranchia of Gastro- poda. Although Pteropoda is not a major group in pelagic zooplankton in terms of abundance and number of species, their ecological characters are…     

钢、水泥需求“S”形规律的三个转变点剖析

本文剖析了人均钢、水泥消费“S”形轨迹的三个重要转变点, 论述了人均消费量和消费强度变化规律的影响因素和内在机制, 阐述了产业部门钢消费强度的倒“U”形轨迹, 在分析国内外经济结构演变趋势的基础上, 提出我国第二产业占GDP比例已经达到顶点, 指出钢、水泥消费强度顶点大小及到来的时间。     

Hydrogeochemical parameters for assessment of groundwater quality in the upper Gunjanaeru River basin,Cuddapah District,Andhra Pradesh,South India

In the management of water resources, quality of water is just as important as its quantity. In order to know the quality and/or suitability of groundwater for domestic and irrigation in upper Gunjanaeru River basin, 51 water samples in post-monsoon and 46 in pre-monsoon seasons were collected and analyzed for various parameters. Geological units are alluvium, shale and quartzite. Based on the analytical results, chemical indices like percent sodium, sodium adsorption ratio, residual sodium carbonate, permeability index (PI) and chloroalkaline indices were calculated. The pre-monsoon waters have low sodium hazard as compared to post-monsoon season. Residual sodium carbonate values revealed that one sample is not suitable in both the seasons for irrigation purposes due the occurrence of alkaline white patches and low permeability of the soil. PI values of both seasons revealed that the ground waters are generally suitable for irrigation. The positive values of Chloroalkaline indices in post-monsoon (80%) and in pre-monsoon (59%) water samples indicate absence of base-exchange reaction (chloroalkaline disequilibrium), and remaining samples of negative values of the ratios indicate base-exchange reaction (chloroalkaline equilibrium). Chadha rectangular diagram for geochemical classification and hydrochemical processes of groundwater for both seasons indicates that most of waters are Ca–Mg–HCO₃ type. Assessment of water samples from various methods indicated that majority of the water samples in both seasons are suitable for different purposes except at Yanadipalle (sample no. 8) that requires precautionary measures. The overall quality of groundwater in post-monsoon season in all chemical constituents is on the higher side due to dissolution of surface pollutants during the infiltration and percolation of rainwater and at few places due to agricultural and domestic activities.     

不同环境下镉对小球藻吸收磷速率的影响

在人工配制的污水中进行静态模拟实验,研究了不同光照强度及不同pH值下,镉对小球藻(Chlorella vulgaris)在悬浮和固定状态下对污水中正磷酸盐的吸收速率的影响。结果表明,镉存在的情况下,在实验所设的各光照强度内,悬浮态小球藻对磷的吸收速率为4~10μg/(h.个),固定化小球藻为12~16μg/(h.个);而相同的镉浓度下,在不同的pH范围中,悬浮态小球藻对磷的吸收速率为1.9~9.4μg/(h.个),固定化小球藻为5.7~12μg/(h.个)。在不同光照强度下,镉总体上降低了小球藻对磷的吸收速率,其中使悬浮藻普遍下降40%~60%,而固定处理使藻受镉的影响较少,至多下降10%~20%,但在个别光照强度下镉反而促进了小球藻对磷的吸收速率。不同pH值时,无论悬浮态还是固定态,镉在大多pH下使小球藻的磷吸收速率下降20%~30%,固定处理并没有减少镉的影响,同样在个别pH下镉促进了对磷的吸收。     

矿物热敏参数测试仪及其在地质找矿中的应用

介绍了国内外第一台矿物热敏参数测试仪研制的原理、应用范围和对一些金属矿物、半导体矿物的测试情况以及仪器在浙江、赣南等地区金矿找矿中的初步应用。     

弹性特征约束下的矿物成分页岩脆性评价方法研究

脆性评价对页岩储层可压裂性评估、设计压裂层段、提升压裂改造效果具有重要意义.但传统基于矿物成分的脆性评价方法将不同矿物成分对脆性指数贡献程度进行平均化, 忽略了不同矿物对岩石脆性影响的差异性.本文采用数字岩石物理实验来标定不同矿物成分对岩石脆性整体特征的影响程度, 定量分析了岩石弹性参数随矿物组分含量的变化关系, 采用基于弹性参数的脆性指数来建立不同矿物成分对页岩脆性的差异性影响关系, 建立不同矿物组分相较于黏土矿物与脆性指数的相对关系及敏感因子, 在弹性参数脆性指数的约束下确定了不同矿物成分在脆性指数中的权重, 提出了基于矿物成分贡献程度自适应变化的脆性评价方法.矿物脆性评价结果与弹性参数脆性评价结果的相关性分析及下寺湾地区岩样脆性评价测试表明, 考虑不同矿物成分的差异性所构建的脆性评价方法更加合理有效.

     

海水海砂混凝土双K断裂参数的确定

采用尺寸为515 mm×100 mm×100 mm初始缝高比从0.1变化至0.8的三点弯曲梁试件,利用试验测得起裂荷载Pini、最大荷载Pmax及对应的裂缝口张开位移CMODc等参数,研究了缝高比a0/h对海水海砂混凝土双K断裂参数的影响。并以相同配合比的淡水河砂梁作为对照组,进一步研究了海砂海水混凝土双K断裂参数与普通混凝土之间的关系。结果发现海水海砂混凝土断裂参数在a0/h=0.25～0.7范围内时可以认为是一常数;海水海砂混凝土梁断裂参数比相同配合比情况下的淡水河砂梁大且对边界影响更加敏感。     

武汉地区自然光照度及其在光敏核不育上的应用

通过对自然光３年的逐日观测表明，一定照度的光时受天气状况影响发生明显变化，晴天光时长、阴雨天光时短，低温伴随着短光时。武汉地区光照度（Ｅ）大于５０ｌｘ，光时大于１３ｈ ４５ｍｉｎ的持续时间是６月￣８月１日，该时段内基本可满足光敏核不育的光照条件。     

北京地区主要活断层活动参数的重力反演

采用1991~1999年首都圈重力测网的重力测量资料,根据地质调查结果确定断层初始运动模型,利用稳健—贝叶斯最小二乘方法反演北京地区4条活断层的活动参数(走滑、倾滑、引张)。反演结果表明:在1991~1999年间,北京地区活断层的运动性质均以走滑和垂直升降为主,兼有伸展特征,但运动速率都不大,约为2 mm/a。北京地区北西走向断层反演的运动特征为左旋走滑正断层,北东走向断层反演的运动特征为右旋走滑正断层。