国庆钨矿钾长花岗岩年代学、地球化学特征及其地质意义   总被引：1，自引：0，他引：1       下载免费PDF全文

李鹏  吕新彪  陈超  曹晓峰  玛依拉·艾山  苏妤芸 《岩石矿物学杂志》2011,30(1):13-24

国庆钾长花岗岩岩体出露于蒙古自治区额济纳旗西南部的盘陀山一带,北邻牛圈子-洗肠井缝合带,LA-ICP-MS测得该岩体的U-Pb年龄为439.1±8Ma。岩体SiO2含量73.31%～74.36%,A/CNK>1.1,K2O/Na2O=1.25～1.40,里特曼指数介于2.06～2.22之间,属于高钾钙碱性、过铝质花岗岩系列,岩体富集大离子亲石元素,亏损高场强元素。稀土和微量元素分析显示钾长花岗岩总体轻稀土元素富集,轻、重稀土元素分馏较低,具有较明显Eu负异常(δEu=0.65～0.77),具K、Rb、Ba、Th等元素富集,Nb、Ce、Zr、Hf、Sm、Y、Yb等元素亏损的特征。综合分析表明,国庆钾长花岗岩为壳源S型同碰撞花岗岩;结合区域构造演化历史,认为国庆钾长花岗岩为古老地壳物质重熔形成,是早志留世月牙山-洗肠井古洋盆闭合同碰撞阶段的产物。同时对该区志留—泥盆纪碰撞伸展环境下成矿前景初步分析,为矿床研究和区域矿产预测工作提供参考。  相似文献   

利用区域气象站资料进行风能资源评估研究   总被引：1，自引：0，他引：1  

吕校华  贺捷颜  王楚凤  李文明 《地质灾害与环境保护》2011,22(2):111-115

简述国内风能资源的开发现状和分布状况,及湖南省区域气象站建设情况。以新宁县黄金气象站为例,统计各种风能参数,分析风能与天气的关系,介绍利用区域气象站资料进行风能资源评估的方法。结果发现,强冷空气入侵时,风速激增,风力加大,风能增至8.3倍以上;强降水时,风速增大,平均风能增至2.4倍。  相似文献   

掘进巷道过断层漏顶区域的施工工艺研究     

吕兆海  张建华  黄相明  丁学福 《中国煤炭地质》2011,(7):49-51,76

清水营煤矿岩体节理与裂隙发育,富水性较好,属于典型的＂三软＂煤层。工作面推进过程中顶板易碎、易冒;煤层开采中,软岩巷道稳定性控制与支护问题,严重制约了该矿井的安全生产。该矿在掘进巷道过断层时,发生突发性漏顶事故,致使巷道停掘。在分析了研究区岩性、构造、地球物理特征以及煤岩的物理力学参数的基础上,针对现场地质条件变化先后采取了两套施工方案对漏顶区进行加固。最终依靠方案二获得了成功,即采用对掘进迎头冒顶区采用水泥、水玻璃浆液加固冒顶区,并对冒空区采用马丽散泡沫充填。施工完成后从迎头退后36m起底,由冒顶区下部通过。现场实践证明,方案二具备安全性与经济性,可为＂三软＂条件下的巷道开采系统设计、岩层控制、安全回采提供地质保障与技术支持。  相似文献   

Effect of nitrogen to phosphorus ratios on cell proliferation in marine micro algae   总被引：1，自引：0，他引：1  

张青田  胡桂坤 《中国海洋湖沼学报》2011,29(4):739-745

The ratio of nitrogen/phosphorus (N/P) is known to affect cell proliferation of some marine micro algae. We evaluated the effect of N/P ratios on the proliferation and succession of phytoplankton using five marine micro algae species. We used two sources of nitrogen, NH₄Cl (N₁) and urea (N₂), and a single source of phosphorous, NaH₂PO₄(P). The optimal N/P ratio that differed among the five species was affected by the source of nitrogen, being as follows (N₁/P, N₂/P in order): Thalassiosira sp. (30/1, 20/1), Heterosigma akashiwo (30/1, 30/1), Chroomonas salina (20/1, 30/1), Chaetoceros gracilis (40/1, 60/1), and Alexandrium sp. (10/1, 30/1). Thus, the source of nitrogen must be considered when analyzing the N/P ratio. Our results provide insight for predicting phytoplankton succession in coastal waters and may be used to forecast the potential risk of harmful algal blooms.  相似文献   

Latitudinal patterns and influencing factors of soil humic carbon fractions from tropical to temperate forests   总被引：3，自引：0，他引：3  

Li Xu  Chunyan Wang  Jianxing Zhu  Yang Gao  Meiling Li  Yuliang Lv  Guirui Yu  Nianpeng He 《地理学报(英文版)》2018,28(1):15-30

Soil humic carbon is an important component of soil organic carbon (SOC) in terrestrial ecosystems. However, no study to date has investigated its geographical patterns and the main factors that influence it at a large scale, despite the fact that it is critical for exploring the influence of climate change on soil C storage and turnover. We measured levels of SOC, humic acid carbon (HAC), fulvic acid carbon (FAC), humin carbon (HUC), and extractable humus carbon (HEC) in the 0–10 cm soil layer in nine typical forests along the 3800-km North-South Transect of Eastern China (NSTEC) to elucidate the latitudinal patterns of soil humic carbon fractions and their main influencing factors. SOC, HAC, FAC, HUC, and HEC increased with increasing latitude (all P<0.001), and exhibited a general trend of tropical < subtropical < temperate. The ratios of humic C fractions to SOC were 9.48%–12.27% (HAC), 20.68%–29.31% (FAC), and 59.37%–61.38% (HUC). Climate, soil texture, and soil microbes jointly explained more than 90% of the latitudinal variation in SOC, HAC, FAC, HEC, and HUC, and interactive effects were important. These findings elucidate latitudinal patterns of soil humic C fractions in forests at a large scale, and may improve models of soil C turnover and storage.  相似文献   

The different influence of the residual layer on the development of the summer convective boundary layer in two deserts in northwest China     

Zhao?Lin  Han?BoEmail author  Lv?Shihua  Wen?Lijuan  Meng?Xianhong  Li?Zhaoguo 《Theoretical and Applied Climatology》2018,131(3-4):877-888

The development of the atmospheric boundary layer is closely connected with the exchange of momentum, heat, and mass near the Earth’s surface, especially for a convective boundary layer (CBL). Besides being modulated by the buoyancy flux near the Earth’s surface, some studies point out that a neutrally stratified residual layer is also crucial for the appearance of a deep CBL. To verify the importance of the residual layer, the CBLs over two deserts in northwest China (Badan Jaran and Taklimakan) were investigated. The summer CBL mean depth over the Taklimakan Desert is shallower than that over the Badan Jaran Desert, even when the sensible heat flux of the former is stronger. Meanwhile, the climatological mean residual layer in the Badan Jaran Desert is much deeper and neutrally stratified in summer. Moreover, we found a significant and negative correlation between the lapse rate of the residual layer and the CBL depth over the Badan Jaran Desert. The different lapse rates of the residual layer in the two regions are partly connected with the advection heating from large-scale atmospheric circulation. The advection heating tends to reduce the temperature difference in the 700 to 500-hPa layer over the Badan Jaran Desert, and it increases the stability in the same atmospheric layer over the Taklimakan Desert. The advection due to climatological mean atmospheric circulation is more effective at modulating the lapse rate of the residual layer than from varied circulation. Also, the interannual variation of planetary boundary layer (PBL) height over two deserts was found to covary with the wave train.  相似文献   

Analysis of a variational Bayesian adaptive cubature Kalman filter tracking loop for high dynamic conditions     

Miao  Zhi-yong  Lv  Yun-long  Xu  Ding-jie  Shen  Feng  Pang  Shun-wan 《GPS Solutions》2017,21(1):111-122

GPS Solutions - Under high dynamic conditions, a robust tracking loop is essential for accuracy positioning with the global position system. In previous studies, the extended Kalman filter...  相似文献   

失地民众的征地拆迁满意度研究——以湖北咸宁市嘉通高速公路征地拆迁为例     

吕冠静  柳瑞禹  刘跃前 《地域研究与开发》2017,36(2)

结合国内征地拆迁的现状和特点,构建失地民众征地拆迁满意度模型,利用湖北省嘉通高速公路沿线村落的调查数据,采用基于PLS法的结构方程模型对征地拆迁民众满意度进行了实证分析。研究表明:失地民众对征地拆迁满意度不高,主要与民众对补偿款的满意程度、就业扶持力度以及信息是否公开透明等影响因素有关,此外,民众除了重视物质方面的补偿,还同等看重信息透明度、政策公平度等“无形”补偿。根据研究结果,建议政府与开发商合作提高就业扶持力度,利用新媒体平台拓展信息覆盖程度,完善纠纷解决机制。  相似文献   

中国极地考察站广域网通信建设与服务现状及展望          下载免费PDF全文

单学武江天乐  汪大立吕渊陆大海  李英旭 《极地研究》2017,29(1):142-150

通过中国极地考察"十五"能力南极两站卫星通信网络系统项目的建设,我国南极考察站的广域网通信能力和站区网络通信能力已经有了很大提高。系统阐述南极两站的广域网通信现状,内容包括南极两站卫星通信链路的建设情况、考察站计算机网络系统建设情况以及该系统所提供的服务情况,涉及卫星通信、局域网以及VOIP等技术;对未来几年极地考察通信中可能会采用的通信技术建设提出建议。  相似文献   

Removal of Organic Dyes in Environmental Water onto Magnetic‐Sulfonic Graphene Nanocomposite     

Sui Wang  Jing Wei  Shasha Lv  Zhiyong Guo  Feng Jiang 《洁净——土壤、空气、水》2013,41(10):992-1001

A magnetic‐sulfonic graphene nanocomposite (G‐SO₃H/Fe₃O₄) was synthesized and characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X‐ray diffraction. It was used for removal of three cationic dyes: safranine T (ST), neutral red (NR), victoria blue (VB), and three anionic dyes: methyl orange, brilliant yellow, and alizarin red, from environmental water. The experimental conditions were optimized, including pH, amount of adsorbent, adsorption kinetics, adsorption isotherms, ionic strength, etc. The results show that G‐SO₃H/Fe₃O₄ can adsorb cationic dyes more efficiently and selectively than anionic dyes at pH 6.0. In the first 10 min of adsorption time, more than 93% of the cationic dyes were removed by the sorbent. Adsorption kinetics follow the pseudo‐second‐order kinetic model well. The adsorption isotherm coincided with Langmuir and Freundlich adsorption models. The maximum adsorption capacities of G‐SO₃H/Fe₃O₄ for ST, NR, and VB dyes were 199.3, 216.8, and 200.6 mg g^?1. The adsorbed cationic dyes were eluted by using different pH values of ethanol as the solvent. The established method was simple, sensitive, and rapid, and was suitable for the adsorption of cationic dyes in environmental water.  相似文献