内蒙古柴胡栏子金矿田燕山期岩浆岩与金矿床

岩相学、岩石化学及稀土元素和微量元素研究证明, 柴胡栏子金矿田的燕山期火成岩组合具有活动大陆边缘弧火成岩组合的特点, 介于典型的靠近海沟的钙碱性弧火成岩与陆内造山火成岩之间的过渡类型。流体包裹体测温 （１８０℃～２９０℃）, 硫同位素 （δ３４ Ｓ＝ ３１‰～７８‰）, 氢氧同位素 （成矿流体以岩浆水为主, 有大气水参与）, 岩石、矿石稀土元素配分特点的相似性等说明金的成矿主要与岩浆作用有关。燕山期岩浆构造作用引起原始矿源层太古界建平群中的金发生活化、迁移, 并在岩浆热液的进一步作用和大气水的参与下, 发生富集沉淀, 形成金矿床。柴胡栏子金矿田的北矿区金矿成矿主要与闪长岩有关, 以蚀变岩型为主。王府矿区金矿化与闪长玢岩脉关系最密切, 以石英脉型为主。岩浆作用为金矿床的形成提供了热源和大部分热液来源, 并且是成矿物质活化和转移的载体。本区金矿床应属与岩浆作用有关的中温热液矿床。     

中-东西伯利亚及俄罗斯远东地区构造和成矿作用的研究进展

俄罗斯地质学家在近20年来以岩石圈板块构造理论和地体分析方法,对中-东西伯利亚和俄罗斯远东地区构造和区域成矿作用的研究取得了一系列重要进展。这些进展集中体现在2个多国合作项目取得的成果和2部最新的科学专著中。作者重点介绍了中-东西伯利亚和俄罗斯远东地区区域构造演化、区域构造和区域成矿单元及一些重要金属矿床的基本特征,并对本区地质演化的某些重要问题（转换陆缘、蒙古-鄂霍茨克造山带等）做了讨论,以此向读者提供一个有关俄罗斯东部地区上述领域基本研究现状的梗概。     

赤鼻棱鳀松果体显微结构研究

本文用组织学方法研究了赤鼻棱鳀（Thrissapurava）松果体的形态结构，结果表明赤鼻棱鳀有松果体窗，并有发达的松果体，感光细胞聚集成团，顶突伸入终囊腔中，终囊类型为折褶型。背囊由单层细胞构成，细胞大而圆，松果体司感光内分泌功能。     

Effect of Three Gorges Dam on Poyang Lake water level at daily scale based on machine learning

Lake water level is an essential indicator of environmental changes caused by natural and human factors. The water level of Poyang Lake, the largest freshwater lake in China,has exhibited a dramatic variation for the past few years, especially after the completion of the Three Gorges Dam(TGD). However, there is a lack of more accurate assessment of the effect of the TGD on the Poyang Lake water level(PLWL) at finer temporal scales(e.g., the daily scale). Here, we used three machine learning models, namely, an Artificial Neural Network(ANN), a Nonlinear Autoregressive model with eXogenous input(NARX), and a Gated Recurrent Unit(GRU), to simulate the daily lake level during 2003–2016. We found that machine learning models with historical memory(i.e., the GRU model) are more suitable for simulating the PLWL under the influence of the TGD. The GRU-based results show that the lake level is significantly affected by the TGD regulation in the different operation stages and in different periods. Although the TGD has had a slight but not very significant impact on the yearly decline of the PLWL, the blocking or releasing of water at the TGD at certain moments has caused large changes in the lake level. This machine-learning-based study sheds light on the interactions between Poyang Lake and the Yangtze River regulated by the TGD.     

中国西北气候干湿变化研究进展

西北地区对全球气候变化十分敏感,研究分析该地区干湿变化特征,对区域发展至关重要.本文从气象(降水、温度、蒸发)、水文(地表水、土壤湿度、陆地水储量)和植被等角度综述了近50年西北地区干湿变化特征.结果 表明:西北整体气温升高,降水增加,呈暖湿化.但考虑陆面因素作用的分析表明该地区呈现东西部分化的格局.考虑蒸发因素的结果...     

内蒙古海拉尔盆地东珺铅锌银矿床地球化学特征

东珺矿床位于海拉尔侏罗纪火山断陷盆地,具有热液蚀变明显、断裂构造控矿显著、矿体多且规模小等特征,为一产于火山岩中的典型热液型铅锌银矿床,火山岩含碱量较高(K2O+Na2O=5.93%～8.26%).Na2O/K2O平均为1.81,轻稀土相对富集(LaN/YbN=16.72～23.31),具轻微的负Eu异常,大离子亲石元...     

一个大气边界层非线性三维数值模式及其在太湖流域的应用

本模式用以K半经验理论为基础的闭合方程组求解,引进了地形作用、动量、热量和水汽的侧向扩散和垂直湍流交换以及凝结加热等物理过程,其中湍流交换系数K是地表粗糙度、几何高度、大气稳定度及风速切变等因子的函数。本模式还考虑了山地、平原和水面在地形高度、地表粗糙度、辐射、蒸发及热交换等方面的差异,在下垫面上建立热平衡方程与边界层内控制方程耦合。将模式应用于太湖流域,计算得到的该流域边界层内温、压、湿、风的分布特征与实际情况相似,模式具有一定的实用性。     

Sodicity effects on hydrological processes of sodic soil slopes under simulated rainfall

Soil salinization can occur in many regions of the world. Soil sodicity affects rainfall‐runoff relationships and related erosion processes considerably. We investigated sodicity effects on infiltration, runoff and erosion processes on sodic soil slopes for two soils from China under simulated rainfall. Five sodicity levels were established in a silt loam and a silty clay with clay contents of 8.5% and 46.0%, respectively. The soils, packed in 50 cm × 30 cm × 15 cm flumes at two slope gradients (22° and 35°), were exposed to 60 min of simulated rainfall (deionized water) at a constant intensity of 125 mm h^?1. Results showed that, for both soils, increasing soil sodicity had some significant effects on hydrological processes, reducing the infiltration coefficient (pr = ?0.69, P  < 0.01) and the quasi‐steady final infiltration rate (pr = ?0.80, P  < 0.01), and increasing the mean sediment loss (pr = 0.39, P  < 0.05); however, it did not significantly affect the cumulative rainfall to ponding (P  > 0.05). Moreover, increasing sodicity significantly increased the Reynolds number and the stream power (pr = 0.78 and 0.66, P  < 0.01, respectively) of the runoff, decreased Manning roughness and Darcy–Weisbach coefficient (pr = ?0.52 and ?0.52, P  < 0.05, respectively), but did not significantly affect the mean flow velocity, mean flow depth, Froude number and hydraulic shear stress. Stream power was shown to be the most sensitive hydraulic variable affecting sediment loss for both soils. Furthermore, as sodicity increased, the values of critical stream power decreased for both the silt loam (R ² = 0.29, P  < 0.05) and the silty clay (R ² = 0.49, P  < 0.05). The findings of this study were applied to a real situation and identified some negative effects that can occur with increasing sodicity levels. This emphasized the importance of addressing the influences of soil sodicity in particularly high risk situations and when predicting soil and water losses.     

A Cloud Point Extraction Approach Developed for Analyzing Pesticides Prometryne and Isoproturon from Multi‐media

A new analytic methodology based on the cloud point extraction coupled with HPLC (CPE‐HPLC) was developed and successfully applied to determination of the pesticides isoproturon (IPU) and prometryne (PRO) from multi‐media (contaminated water, soil, and food vegetable). Several non‐ionic surfactants including poly ethylene glycol 6000 (PEG‐6000), TritonX‐114, and Triton X‐100 were comparatively analyzed as extraction solvents. Other parameters such as surfactant concentration, ionic strength, and equilibration temperature, and duration were also investigated. The optimal conditions for CPE were presented with 2.4% w/v PEG‐6000, 11% w/v Na₂SO₄ and heating assistance at 50°C for 25 min. The calibration curves for the two analytes were linear ranging from 0.001 to 10.0 mg L^?1, with correlation coefficients being 0.99 determined by a HPLC–UV detector. Under the condition, the average recoveries were 85.4–90.6% for water, 84.4–92.7% for soil, and 84.4–92.1% for vegetable. Thus, the method presented here was proved to be rapid, efficient, and green for extraction and determination of isoproturon and prometryne residues from food and multi‐environmental media.     

用动态时间序列周期分析预测模型作郑州汛期降水预报

动态时间序列周期分析预测模型是将多层递阶方法与逐步回归周期分析的基本原理相结合,可以有效地选取时间序列的各个隐含周期。利用所选取的隐含周期,可作更长时间的预测。本文以郑州汛期降水为样本,对该预测模型进行了应用及讨论。