几内亚共和国红土型铝土矿床成矿探讨

在全球广泛分布着中生代(Mz)基性岩浆岩,但由此形成的风化残积红土型铝土矿床主要集中在低纬度带。也就是说,除成矿母岩外,低纬度带的自然气候环境是红土型铝土矿成矿的另一决定性因素。但在低纬度带的成矿母岩分布区域内,是否成矿或矿体的优劣,取决于矿源层的厚薄、地形地貌特征以及水文地质条件等。铝土矿的形成过程,是自成矿母岩风化初始阶段至红土形成阶段,铝铁物质逐渐富集的过程。     

DRAINMOD-S模型参数的全局灵敏度分析

为有效进行DRAINMOD-S模型参数的优选,更好地理解参数变化对模拟结果的影响,开展了模型参数灵敏度分析。以南通市九龙垦区暗管排水脱盐试验为例,采用Morris全局定性分析方法检测了DRAINMOD-S模型模拟土壤剖面含盐量时侧向饱和导水率K_sat、水动力弥散系数D、地表最大蓄水深度S_m、相对不透水层深度I_m、排水系数D_r及地下水初始埋深W 6个参数的灵敏度。结果表明:K_sat对模拟结果影响最为显著,D、S_m和D_r次之,而W与I_m影响最小;各个参数间的非线性作用存在差异,以K_sat最为显著。为保证模型模拟质量,对敏感性参数应提高现场测试精度,在模型运行时,对灵敏度大的参数应进行重点调整,同时也不可忽视非线性作用较强的参数,从而有效地指导模型的参数率定,提高模型的适用性。     

元谋干热河谷区蒸发量减少原因的灰色关联分析

元谋干热河谷区气候炎热干燥、植被稀疏、生态系统脆弱。近２０年来蒸发量明显减少，本文采用灰色系统关联度理论，对各有关因素影响的大小进行了计算和排序。     

北京都市区社会空间结构及其演化(1982-2000)

利用2000年的第5次人口普查数据和1982年的第3次人口普查数据,采用因子分析和聚类分析技术研究了近20年来北京都市区的社会空间结构及其演化。对比1982年的情况,2000年北京都市区社会空间结构的主因子、社会区类型、模式及其形成机制均发生了较多的变化。1982年北京都市区的社会空间结构相对简单,整体上表现出一定的同质性特点;2000年的社会空间结构则趋于复杂,诸社会区之间主要以同心圆的方式组合,也伴有多核心和扇形结构,异质性的特征十分突出。论文最后从宏观、中观和微观3个层次提出了一种城市社会空间结构演化的交叉式网络机制,认为它有效地推动了计划经济特色明显的北京都市区社会空间结构向市场转型条件下的社会空间结构转化。     

四川地区月降水量的一种预测模型

本文对1960～1979年四川地区48个测站的月降水资料,在稳斜因子分析的基础上,用ARIMA(p,d,q)模型进行随机建模。时间序列分别来源于PROMAX斜旋转解的因子得分。因子得分序列的主周期由周期图和方差分析方法求出,-维ARI-MA(p,d,q)模型识别用Box-Jenkins方法进行。对1980年的月降水量预测结果表明,距平预报的年平均准确率为58.33％。     

METHODS OF VARIMAX ROTATION IN FACTOR ANALYSIS WITH APPLICATIONS IN CLINICAL AND FOOD CHEMISTRY

Orthogonal rotations,e.g,the varimax rotation,are common practice in factor analysis.However,theterm varimax rotation does not refer to a unique procedure,since several different types of rotation arepossible.In this paper six different types of rotation are examined(raw varimax of loadings,normalvarimax of loadings,raw and normal varimax of scores,eigenvalue-weighted varimax of loadings andArthur varimax)from both a theoretical and practical point of view.It can be concluded that an adequateapplication of these methods can often simplify the interpretation of the calculated factors.     

Geochemical characterization of a karst polje – an example from Sinjsko polje, Croatia

 The poljes of the Adriatic Coast are rather special features whose like is not found anywhere else in the world. The delineation of this unique landform feature by its geochemical characteristics has been attempted by using examples from Sinjsko polje, which represents a typical karst polje in the Adriatic Coast, or the area of the Dinaric Karst. Factor analysis was performed on 96 samples collected in a regular grid of 1×1 km which covered the entire area of the Sinjsko polje valley. Another factor analysis was performed in a regular grid of 5×5 km that comprised 41 samples in the karstic environment. In this manner two factor models were created and closely inspected for possible differences due to the peculiar properties arising from two geochemically different environments. Within the polje itself it was possible to evaluate three factors, while four factors were identified to be significant for the explanation of the geochemical structure of data assessed in the regular 5×5-km grid. This grid includes the area of Sinjsko polje and its wider neighborhood. The Ba/Sr index reveals striking differences in drainage patterns between the polje itself and the surrounding area. Received: 3 May 1996 · Accepted: 25 June 1997     

Cation exchange processes and human activities in unconfined aquifers

During the 1999–2002 water years, a hydrogeological research project was carried out on the unconfined aquifer of Trifilia in the Peloponnese. Seawater intrusion due to overpumping, and intensive use of fertilizers caused the groundwater quality degradation that is a typical case for the coastal aquifers in Greece. Isopiezometric maps along with ion distribution balances, ion distribution maps and factor analysis indicate the existence of three zones of groundwater quality. In the first zone of saline water, a cation exchange process between the Ca²⁺ of sediments and the Na⁺ of groundwater contribute to the formation of the water type Na⁺-Ca²⁺-Cl^–. In the second zone, which is considered as a transition zone, dominate the Ca²⁺-Na⁺-HCO₃^–-Cl^– water type. In the third zone of Ca²⁺-HCO₃^–-SO₄^2– water type, relationships among Ca²⁺, SO₄^2–, NO₃^– and NH₄ can be attributed to the dissociation of ammonium nitrate and sulfate fertilizers on one hand, and Ca²⁺ derivation from cation exchange processes between water, rocks and clay minerals, such as smectite and illite, on the other.     

具有免疫活性多糖海洋细菌菌株的筛选

从厦门海区潮间带的动植物体及底泥分离到的177株海洋细菌中筛选出一株高产胞外多糖的1202菌株.其产生的胞外多糖可显著地促进昆明种小鼠脾淋巴细胞IL 2(白介素 2)的合成,并对小鼠S180肉瘤具有较强的抑制作用.经初步分类鉴定,确定该菌株归属于土壤杆菌属(Agrobacteriumsp.).     

黄渤海北强风物理量因子场诊断分析

本文通过对低槽绕涡旋转型各物理量因子场的诊断分析,揭示了各物理量因子场造成黄渤海北强风(≥8级)的物理机制及其特征,获得了一批与北强风关系密切的物理量因子场。