Mantle-derived noble gases in ore-forming fluids of the granite-related Yaogangxian tungsten deposit,Southeastern China

More than 90% of the tungsten resources of China are in the Nanling region of South China, and the Yaogangxian vein deposit is the largest tungsten deposit in this region. The tungsten deposits have ages of 150–160 Ma, and are spatially, temporally and genetically related to granites which were previously believed to be produced by crustal anatexis. This paper provides He and Ar isotope data of fluid inclusions in pyrite and arsenopyrite from the Yaogangxian W veins. ³He/⁴He ratios range from 0.41 to 3.03 Ra (where Ra is the ³He/⁴He ratio of air?=?1.39?×?10^?6), and ⁴⁰Ar/³⁶Ar ratios from 328 to 1,191. Moreover, there are excellent correlations between He and Ar isotopic compositions. The results suggest that the ore-forming fluids are a mixture between a crustal fluid containing atmospheric Ar and crustal ⁴He and a fluid containing mantle components. It is likely that the former is a low temperature meteoric fluid, and the later is a fluid exsolved from the W-associated granitic magma, which formed by crustal melting induced by intrusion of a mantle-derived magma.     

干旱半干旱区农田土壤风蚀特征及参数化研究进展

干旱半干旱地区是中国的农业后备战略基地,然而近年来该地区农田土壤风蚀现象严重,沙/尘释放量显著增大,威胁农业的可持续发展和生态系统平衡。目前绝大部分的天气和气候模式仅考虑了沙漠地表起沙,忽视退化农田的土壤风蚀起沙,导致起沙通量模拟存在很大的不确定性。对20世纪50年代以来干旱半干旱区农田土壤风蚀起沙特征及参数化做了详细的分析总结,回顾并梳理了干旱半干旱区农田土壤风蚀观测和数值模拟的研究脉络以及存在的问题,为提高农田起沙的模拟精度提供了有效参考,对中国干旱半干旱区农田土壤风蚀防治、土地荒漠化治理以及理解未来土地利用改变对大气污染的影响具有重要意义。     

Influencing factors for catalytic oxidation of mine gas to methanol in liquid phase

The influencing factors for liquid phase catalytic oxidation of mine gas to methanol （in form of CHaCOOCH3） are studied using the self-established experimental apparatus. The results show that CH3COOCH3 （target product） is obtained by using CH3COOH as reaction solvent, and the yield of target product increases with the increasing of reaction temperature, gas pressure and reaction time. In the mine gas-Pd（OAc）2-CHaCOOH system, the yield of CHaCOOCH3 increases with the increasing of addition of Pd（OAc）2 which is redox catalyst for mine gas conversion. The yield of CH3COOCH3 will be greatly improved by composite additional oxidant which is obtained by equimolar mix of p-benzoquinone with NO2.     

硅酸盐熔体和流体中金的性质及行为研究进展

岩浆演化过程中岩浆—流体阶段发生的相转变过程控制了元素在两相之间的分配行为。作为与岩浆热液活动有密切成因联系的金矿床,其在硅酸盐熔体和流体中的性状及两相间的分配行为是控制该类矿床成矿的重要物理化学因素。介绍了金在流体、熔体中的性状,论述了其在流体/硅酸盐熔体间的分配行为不仅受温度、压力、氧逸度等物理化学条件的影响,还受流体组分(阴离子、阳离子)、熔体组成(Na2O+K2O/Al2O3,Na/K,SiO2,NBO/T)的制约;最后对目前实验研究存在的问题、改进方法以及今后的研究方向进行了探讨。     

Assessment of groundwater changing trends through the generalized large well method with confined–unconfined flow model in open-pit mine area

In this paper, a simple but accurate method (generalized large well method) is presented to assess groundwater level trends during mine exploitation. This method includes a mathematical model of confined–unconfined well flow and a corresponding analytical solution. Based on the method, a case study was analyzed with data from the Yimin open-pit mine. As a result, the radius of groundwater level rose, along with the increase of the exploitation intensity. Moreover, a suitable value of pumping flow could be beneficial to understanding potential groundwater contamination concerns. Additionally, it has also been predicted that the groundwater level of the Yimin open-pit mine will change within the next 3 years. The Yimin open-pit mine case study demonstrates the validity of the analytical method explained herein. The presented methodology provides a theoretical foundation for assessment of groundwater changing trends in other open-pit mines with similar hydrogeological conditions.     

华南陆块陆内成矿作用的一些科学问题

华南陆块由扬子地块和华夏地块组成,是全球罕见的世界级多金属成矿省,成矿潜力巨大。华南陆块的形成和演化,受到了很有特色的陆内大陆动力学过程的影响,其中的晚古生代地幔柱成矿系统、中生代大面积低温成矿系统、中生代大花岗岩省成矿系统等陆内成矿系统,在全球背景中很有特色,是全球研究陆内成矿作用的理想基地。对华南陆块地质历史时期的大陆动力学过程如何制约上述成矿作用的发生,以往已开展不同程度的研究并取得重要成果。笔者在论述这些研究进展的基础上,提出了三大成矿系统需要进一步研究的一些科学问题。     

山东半岛东部近岸表层沉积物放射性核素的季节性变化及其环境指示意义

基于2019年4月、7月、10月、12月渤黄海共享航次取得山东半岛东部近岸H01和H02站位多个季节沉积物样品,通过低本底γ能谱仪分析得到其表层沉积物放射性核素7Be、210Pbex、228Thex和137Cs活度数据.结果 表明,短半衰期核素7Be、228Thex与长半衰期核素210Pbex、137Cs在同一站位的季...     

光学综合孔径干涉成像的关键技术及多光束干涉仿真

闭合相位技术、U -V覆盖技术和像重构技术是光学综合孔径干涉成像的三个关键技术。文中简要介绍了光学综合孔径技术的发展历史、这三种关键技术和光学综合孔径望远镜阵的构成 ,对之进行了多光束干涉的计算机仿真和实验仿真 ,两者结果一致说明了光学综合孔径干涉成像技术中有关干涉的理论的正确性 ,指出了下一步的研究方向。     

论企业家的竞争意识

企业家的竞争意识是企业能否取得竞争胜利的基本条件之一。从思维方式、心理品质、竞争观念等三个方面就企业家应具备什么样的意识方可应对市场竞争并取得胜利进行探讨 ,以求让企业家们为更好地应对竞争挑战而自觉地培养良好的竞争意识提供帮助。     

江西省高速公路气象服务效益评估及气象灾害影响分析

基于江西省气象服务中心开展的有关高速公路气象服务问卷调查,分析了江西省高速公路气象服务的现状、敏感性、气象服务需求和满意度,在此基础上对江西省高速公路气象服务效益进行评估,并分析了高速公路主要的致灾气象因子。结果表明:1)高速公路对气象条件有很强的敏感性,高速公路安全对灾害预警、短期天气、重大节假日天气表现最为敏感;高速公路行业对目前的高速公路气象服务总体满意。2)江西省高速公路应用气象信息产品产生的年综合增值占本行业年产值的比率为2.25%—3.15%,且2009—2013年高速公路气象服务效益逐年递增。3)低能见度、路面结冰、路面湿滑是高速公路的主要致灾气象因子;利用相关气象资料和高速公路灾害数据,确定低能见度和路面结冰、降雨等高速公路致灾气象因子临界值,对高速公路行业的气象防灾减灾具有一定的指导意义。