广西输电线路覆冰典型年份的环流特征分析     

覃武  罗小莉  钟利华  周绍毅  苏志 《沙漠与绿洲气象(新疆气象)》2019,13(1):110-116

采用NCEP/NCAR逐月再分析资料、广西北部43个气象台站的温度、湿度、风、降水、导线覆冰等观测资料以及广西输电线路覆冰资料,建立雨凇覆冰厚度计算模型,并得出气象台站的历史覆冰厚度序列。采用数理统计和合成分析等方法研究典型覆冰年份的时空特征、环流背景及气象要素变化特征,结果发现:广西输电线路覆冰主要出现在冬季的桂北,并有逐年减轻的趋势,MannKendall突变检验表明,存在1个明显的突变点,出现在1985年;广西典型覆冰年份,500 hPa欧亚大陆中高纬地区呈明显的"两槽一脊"型,广西高空处于南支槽前,地面受冷高压脊控制;赤道中东太平洋,从夏季到秋季,海温由偏高转为偏低,到冬季SSTA维持为负距平,说明广西输电线路覆冰与LA NINA事件有较密切的关系。当日最低气温在0.2℃以下,风速5 m·s-1,并伴有雨凇和弱降水,低温寡照天气时容易出现覆冰。  相似文献   

铝合金钻杆的优越性及在地探深孔中的应用前景   总被引：1，自引：0，他引：1       下载免费PDF全文

鄢泰宁  薛维  卢春华 《探矿工程》2010,37(2):27-29

在归纳铝合金钻杆众多优点的基础上,介绍铝合金钻杆与钢接头的连接方式、过盈配合,举例分析铝合金钻杆可显著减少深孔钻进大钩载荷、转盘扭矩和泵压损失的效果,探讨了铝合金钻杆在地探深孔中的应用前景。  相似文献   

复合片取心钻头的研制及其应用     

刘梦溪  康丽生等 《中国煤田地质》2001,13(3):69-74

由金刚石共晶体与硬质合金基座制成的复合体是一种新型超硬研磨材料，用它和特制的钻头胎体制成的复合片取心钻头适用于可钻性小于Ⅶ级岩石的钻进，它的应用可大大提高煤系地层（特别是煤心）的采取率。  相似文献   

一个适合于金属合金水热实验方法的探讨     

郁云妹 Gamm.  CH 《矿物学报》1995,15(1):55-60

文章以银-钯（Ag－Pd）合金＋AgCl在HCl-H2O对热液中的溶解度测定为例，叙述了用合金作为实验初始物和同时测定合金组成的方法。本实验结果与前人在相同实验条件仅用不同方法所获得的结果比较后指出：①本实验中测得的银溶解度位于Zotov和Seward的研究结果之间；②从实验中测得把的溶解度，计算或的存在形式和控制把溶解度反应式的平衡常数与Gammons一致，所有这些结果都表明，用Ag－Pd合金＋AgCl作为溶解度反应的初始物研究该合金组成的方法是可行的。该方法提出了控制体系氧逸度的新方法，为从实验上研究成矿元素在低温下的热液行为提供了可能。  相似文献   

脉冲电镀复合片钻头的试制          下载免费PDF全文

张绍和 《探矿工程》1995,(4):25-25,29

研究了脉冲电镀法的优越性，合理选用了电镀复合片的镀层成分，室内试验表明：利用脉冲电镀法制造复合片及其钻头是可行的，使用结果比较理想。  相似文献   

缅甸铂族金属砂矿中的矿物种类   总被引：1，自引：0，他引：1  

赵怀志  陈立新 《矿物学报》1994,14(3):285-291,T001

采用电子探针分析（ＥＰＭＡ），对缅甸铂族金属砂矿中的矿物种类进行了研究。物质组成研究查明：主要组合矿物是Ｐｔ、Ｉｒ、Ｏｓ、Ｒｕ的自然元素和金属互化物。主要矿物是自然铂矿、铁铂合金、钌铱锇矿、等轴锇铱矿和铱锇矿。次要及稀有矿物是铂族金属的硫化物、砷化物、包括（Ｒｈ、Ｐｄ、Ｐｔ）２Ａｓ和（Ｒｈ、Ｐｄ、Ｐｔ、Ｎｉ）２Ａｓ两种陌生矿物、锑化物，以及含铂族元素的Ｆｅ、Ｎｉ、Ｃｕ硫化物。  相似文献   

Dynamic behavior and applicability of lead alloy absorber     

李亚琦  李小军  刘锡荟 《地震学报(英文版)》2005,18(1):89-98

Introduction As the result of economic development, metropolitans spring out in China. In metropolitans,the cities contact with each other through life line systems, the density of population is larger thanother areas, and social treasure in the unit area is much higher than other cities (GAO, 2003). Atthe same time, the risk of potential earthquake disaster in metropolitans increases greatly. One ofcharacters of metropolitan earthquake damage is that each city in the metropolitan will …  相似文献   

乙酰胺-尿素-NaBr熔体中Ce-Sm-Co合金膜的电化学制备          下载免费PDF全文

郭承育  王建朝  陈必清 《盐湖研究》2006,14(4):33-38

应用循环曲线法研究了在353 K的乙酰胺-尿素-NaBr熔体中Co2+在Cu电极上的电化学行为,获知Co2+电还原为金属Co是一步不可逆过程,测得a=0.25和Do=3.24×10-6cm2.s-1;而Ce(Ⅲ)、Sm(Ⅲ)不能单独还原为Ce和Sm,但可以被Co(Ⅱ)诱导而共沉积;由恒电位电解法得到非晶态的Ce-Sm-Co合金膜,合金膜中Ce和Sm的含量随电位、时间和浓度的变化而变化。其合金膜中Sm的最高质量分数可以达到47.98%,Ce的最高质量分数可以达到47.32%。  相似文献   

Comparison of components and distribution of heavy metals in sediments, suspended particulate matter and surface coatings in natural waters     

Deming DONG Yongzheng LU Xiuyi HUA Liang LIU Xiue SHEN 《中国地球化学学报》2006,25(B08):200-201

Solid phases, such as surface coatings （SC）, suspended particulate matter （SPM） and deposited sediments （DS）, contribute to the pool of heavy metals in natural waters. Their existing and forming conditions lead to potential differences in enrichment capacity of pollutants, chemical compositions and crystals. In this study, the contents of heavy metals in SC, SPM and DS were determined by GF-AAS after digestion with a mixture of concentrated HNO3 and HClO4. The selective extraction method was employed to remove Fe, Mn oxides and organic matters and associated heavy metals （Cu, Pb, Zn）. X-ray diffraction analyses were performed to characterize the crystals in the samples. The results showed that no significant difference in the contents of Fe-oxides in DS, SPM and SC was found, but the contents of Mn-oxides and organic matter follow the order of SC〉SPM〉DS. The significant crystal characters were observed in DS, SPM and SC, and the kinds of minerals and crystallization degree follow the order of DS〉SC〉SPM. In addition, quartz was the most important matter of crystals in the solid phases. Enrichment capacity follows the order of SPM〉SC〉DS for Pb, Cu and Zn. Organic matter was the major sorbent for Cu, and Mn oxides and organic matter played an important role in the enrichment of Zn. However, Pb was absorbed mainly by Fe oxides. Moreover, compared with Fe oxides and organic matter, Mn oxides had a great enrichment capacity for these metals. Although DS, SPM and SC were formed in the same water system, contents of chemical components, crystals and enrichment capacities to heavy metals were obviously different.  相似文献   

Gaseous transport and deposition of gold in magmatic fluid: evidence from the active Kudryavy volcano, Kurile Islands     

Marina A. Yudovskaya  Vadim V. Distler  Ilya V. Chaplygin  Andrew V. Mokhov  Nikolai V. Trubkin  Sonya A. Gorbacheva 《Mineralium Deposita》2006,40(8):828-848

The distribution of gold in high-temperature fumarole gases of the Kudryavy volcano (Kurile Islands) was measured for gas, gas condensate, natural fumarolic sublimates, and precipitates in silica tubes from vents with outlet temperatures ranging from 380 to 870°C. Gold abundance in condensates ranges from 0.3 to 2.4 ppb, which is significantly lower than the abundances of transition metals. Gold contents in zoned precipitates from silica tubes increase gradually with a decrease in temperature to a maximum of 8 ppm in the oxychloride zone at a temperature of approximately 300°C. Total Au content in moderate-temperature sulfide and oxychloride zones is mainly a result of Au inclusions in the abundant Fe–Cu and Zn sulfide minerals as determined by instrumental neutron activation analysis. Most Au occurs as a Cu–Au–Ag triple alloy. Single grains of native gold and binary Au–Ag alloys were also identified among sublimates, but aggregates and crystals of Cu–Au–Ag alloy were found in all fumarolic fields, both in silica tube precipitates and in natural fumarolic crusts. Although the Au triple alloy is homogeneous on the scale of microns and has a composition close to (Cu,Ni,Zn)₃(Au,Ag)₂, transmission electron microscopy (TEM) shows that these alloy solid solutions consist of monocrystal domains of Au–Ag, Au–Cu, and possibly Cu₂O. Gold occurs in oxide assemblages due to the decomposition of its halogenide complexes under high-temperature conditions (650–870°C). In lower temperature zones (<650°C), Au behavior is related to sulfur compounds whose evolution is strongly controlled by redox state. Other minerals that formed from gas transport and precipitation at Kudryavy volcano include garnet, aegirine, diopside, magnetite, anhydrite, molybdenite, multivalent molybdenum oxides (molybdite, tugarinovite, and ilsemannite), powellite, scheelite, wolframite, Na–K chlorides, pyrrhotite, wurtzite, greenockite, pyrite, galena, cubanite, rare native metals (including Fe, Cr, Mo, Sn, Ag, and Al), Cu–Zn–Fe–In sulfides, In-bearing Pb–Bi sulfosalts, cannizzarite, rheniite, cadmoindite, and kudriavite. Although most of these minerals are fine-grained, they are strongly idiomorphic with textures such as gas channels and lamellar, banded, skeletal, and dendrite-like crystals, characteristic of precipitation from a gas phase. The identified textures and mineral assemblages at Kudryavy volcano can be used to interpret geochemical origins of both ancient and modern ore deposits, particularly gold-rich porphyry and related epithermal systems.  相似文献