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1.
利用等温溶解法测定了三元体系Li2C2O4-Li2CO3-H2O(25℃)的溶解度,相平衡图中有三个相区,即LihCGO4、Li2CO3、Li2C2O4+Li2CO3。两条单变量曲线,一个共饱点。  相似文献   

2.
本矿床是我国金红石矿床重要的成因及工业类型,为具有特定化学成分的岩石在特定变质条件下形成的。本文通过对大量数据的处理,查明了化学成分与成矿的关系:高Al2O3、MgO、Fe2O3+FeO、K2O、P2O5、H2O+、MnO,低SiO2、CaO、Na2O、CO2、S等,利于钛富集;高TiO2、MgO、P2O5、S,低SiO2、CaO、K2O、Al2O3、Fe2O3/FeO,利于金红石形成;高Sc、Zr、Ni、Zn及La/Yb,低Y、Nb、Th、Cd、Ba、Be、ΣREE,利于金红石纯度提高。对研究矿床成因及寻找新的同类矿床等有重要意义  相似文献   

3.
四川石棉大水沟独立碲矿床堪称世界首例,其矿体两侧的围岩蚀变较窄,且蚀变带与矿脉及未蚀变岩呈清楚而截然的接触关系。主要围岩蚀变为白云石化、白(绢)云母化、云英岩化及电气石化等。这些蚀变作用分别发生于177.7~165.1Ma和91.71~80.19Ma。蚀变作用过程中SiO2大量析出,Al2O3、TiO2、CaO、MgO、K2O、H2O、CO2、Fe2O3、MnO则有不同程度地带入。与此同时,REE在此过程中包集体迁出,Te、Bi、AS等元素的含量则决定于蚀变作用及其强度,而与原岩无关。  相似文献   

4.
全球气候变暖带来的危害促使国际社会在 CO2 减排方面达成了共识,近年来备受关注的碳捕集与封存(carboncapture
andstorage,简称 CCS)技术作为 CO2 减排的重要手段,正处于快速发展阶段。CO2 海洋封存是 CCS技术中实现 CO2 减排的一项最具发展潜力的方法,认识其发展现状对于进一步研究 CO2 封存具有重要参考价值。 CO2 海洋封存的发展现状作了具体分析,阐述了 CO2 海洋封存的方法,包括海洋水柱封存、海洋沉积物封存、CO2 置换天然气水合物封存和海洋增肥4种方法。指明CO2 海洋封存现阶段存在封存成本极高、存在泄露风险、政策法规缺失和公众认知度低4个问题。建议应从完善法律法规、加强国际合作、重视监测技术、提高公众认知4个方面做好 CO2 海洋封存下一步的研究与实践工作。   相似文献   

5.
系统试验了在过滤海水中加入不同浓度的CaO2后DO、pH的变化规律,以及不同浓度的CaO2对尖吻鲈、罗非鱼的饲养及运输的增氧效果。结果表明;加入CaO2 15×10^-6 ̄20×10^-6,能很快增加水中DO,对抢救尖吻鲈鱼苗浮头有较好效果,在平时饲养中施CaO2 10×10^-6 ̄20×10^-6增氧效果也明显。在罗非鱼高密度暂养或运输中,施入CaO2 45×10^-6 ̄75×10^-6对增氧,  相似文献   

6.
文章在计算水溶液化学组份平衡分布及其pH值的基础上,分析和讨论了封闭系统中CaCO3溶解或沉淀所引起的水化学后果,并依据计算数据和借助作图的办法得出了如下结论,即CaCO3溶解会使水溶液pH值增大,H2CO3含量减少;相反,CaCO3沉淀会使水溶液pH值减小,H2CO3含量增多。  相似文献   

7.
在HNO_3·EDTA─FezO_3·H_2SO_4介质中,铌(Ⅴ)─氟化铵─酒石酸─偶氮胂(Ⅲ)体系形成灵敏的导数极谱催化波,峰电位在─0.86V(VS·SCE),Nb_2O_5量在0─2.5μg/25ml范围内与峰电位成线性关系,拟定了一个不经分离,适用于硅酸盐,碳酸盐及化探样品中微量铌的测定方法。  相似文献   

8.
本文确定了黄土中古土壤有四种双层淀积类型。第一和第二种是由两层CaCO3结核构成的,第三种是由CaCO3和CaSO4构成的,第四种是由CaCO3与Al2O3、Fe2O3构成的。根据CaCO3淀积层成因分析得知,西安附近第一层古土壤具二元发生特点。该层古土壤上部的CaCO3淀积层代表碱性土壤发育时期。下部的CaCO3淀积层代表中酸性土壤发育时期。因为有些古土壤发育时出现过气候变化,所以具CaCO3淀积层的古土壤不一定是碱性的。具CaCO3与Fe2O3·Al2O3构成的双层淀积是酸性土壤的标志。  相似文献   

9.
棚沟金矿床赋存于华北古陆块南缘前寒武纪花岗岩中,在空间上受区域韧性剪切带中的燕山末期花岗斑岩控制。根据矿床地质特点判断属中低温热液型金矿。通过岩石矿物组合及包裹体组成、性质、同位素等测试,确定成矿物质来源于围岩,成矿流体来源于变质水且有岩浆水与雨水的混入。通过电子探针测定的岩矿组分,计算围岩成岩及变质温度,以及成矿温度、压力和沉淀条件,认为金矿床的成矿作用,主要表现为减压环境中的岩浆热液充填和交代蚀变,以及热液的泡腾作用。从找矿标志角度确定富CO2的泡腾包裹体群、液相高硫富HCO-3、气相高CO2和高CO2/H2O比值等参数是寻找此类金矿的重要标志  相似文献   

10.
综合利用气体组分分析、铸体薄片分析、孔隙定量分析及常规物性分析等手段,对 CO2-地层水-砂岩的反应机理进行了研究。结果表明:早期 CO2 溶于水形成碳酸,使得骨架颗粒及早期胶结物溶解形成大量的孔隙,晚期过量的 H+ 消耗使得溶液呈碱性,下伏热流体所携带的 HCO-3 和 CO2 水解形成的 HCO-3 与早期地层中的 Mg2+ 、Fe2+ 化合形成碳酸盐胶结物,以铁白云石为典型代表,在碱性环境下进行沉淀堆积,堵塞孔隙及喉道,综合早期建设性成岩作用及晚期破环性成岩作用,最终降低了储层质量,尤其在 CO2 体积分数大于10%时表现最为明显。   相似文献   

11.
乌苏里江唇耗氧率和窒息点的初步研究   总被引:2,自引:0,他引:2  
进行不同温度和不同规格人工养殖的乌苏里江唇(Hemibarbus labeo)耗氧量(MO2)、耗氧率(WO2)和窒息点(SO2)的初步测定。结果表明:水温16~28℃范围内,随着水温的升高,耗氧率、耗氧量和窒息点都表现出增大的变化趋势。温度和耗氧率的回归方程:1龄鱼体重11 g的为WO2=0.0142T-0.0863(R2=0.9617),2龄鱼体重60 g的为WO2=0.0138T-0.1121(R2=0.97);温度和窒息点的回归方程:1龄鱼体重8 g的为SO2=0.0298T-0.1891(R2=0.977 8),2龄鱼体重40 g的为SO2=0.048 8T-0.402 5(R2=0.999 7)。体重20~100 g范围内,水温25℃时,随着体重规格的增大,耗氧量逐渐升高,耗氧率逐渐减小。体重和耗氧率的回归方程为WO2=0.7825W-0.2898(R2=0.947 4),体重和耗氧量的回归方程为MO2=0.7837W0.7097(R2=0.991 6)。唇鱼的昼夜耗氧率(水温25℃,体重72 g)有一定的变化趋势,早间4~10时耗氧率较高,平均在0.332±0.046 mg/(g.h),午间11~19时中等,在0.287±0.030 mg/(g.h),晚间20~3时较低,在0.251±0.029 mg/(g.h)。  相似文献   

12.
In this study, genes of two distinct tissue inhibitors of metalloproteinases-2 (TIMP-2) from Japanese puffer fish Fugu rubripes, Fugu TIMP-2a and TIMP-2b, were cloned. The open reading frames of Fugu TIMP-2a and TIMP-2b cDNAs are composed of 660 and 657 nucleotides and 220 and 219 amino acids, respectively. Both Fugu TIMP-2s contain 12 cysteine residues, which might form six disulfide bonds as in other animals' TIMP-2s. Reverse-transcribed polymerase chain reaction analysis showed the mRNAs of Fugu TIMP-2a and TIMP-2b to be expressed in some tissues examined with different expression patterns. These findings suggest that the two distinct Fugu TIMP-2s might perform different functions in Fugu tissues.  相似文献   

13.
文昌鱼对几种环境因子及污染物的耐受极限初步研究   总被引:1,自引:0,他引:1  
<正>文昌鱼(Branchiostoma belcheri)隶属脊索动物门头索动物亚门,是全世界现存动物中与脊椎动物关系最近的一类非脊椎动物[1],被称为生物进化的“活化石”。它营养丰富,干品蛋白质含量约达70%左右,还含有较高的磷和碘,脂肪含量低,具有较高的  相似文献   

14.
Content analysis of scientific papers emanating from Antarctic science research during the 25 years period (1980-- 2004) has been carried out using neural network based algorithm-CATPAC. A total of 10 942 research articles published in Science Citation Indexed (SCI) journals were used for the study. Normalized co-word matrix from 35 most-used significant words was used to study the semantic association between the words. Structural Equivalence blocks were constructed from these 35 most-used words. Four-block model solution was found to be optimum. The density table was dichotomized using the mean density of the table to derive the binary matrix, which was used to construct the network map. Network maps represent the thematic character of the blocks. The blocks showed preferred connection in establishing semantic relationship with the blocks, characterizing thematic composition of Antarctic science research. The analysis has provided an analytical framework for carrying out studies on the con- tent of scientific articles. The paper has shown the utility of co-word analysis in highlighting the important areas of research in Antarctic science.  相似文献   

15.
在最新的能接收到北斗三号新信号B2a及B2(B2a+b)的MGEX测站数据基础上,分析BDS-3信号的载噪比、多路径及卫星的三维位置精度因子(PDOP)。结果表明,与GPS相比,BDS的载噪比B2(B2a+b)>B2a≈L5>B3≈B2b>B1≈L1>L2,多路径误差B2(B2a+b)相似文献   

16.
玲珑矿田含有两种类型金矿床,一是蚀变岩型金矿床,二是石英脉型金矿床。该文重点研究玲珑金矿田西山矿区石英脉型金矿床中流体包裹体的特征。石英脉型金矿床分布在玲珑帚状构造之中,含金石英脉受"帚状构造"的断裂和节理控制,有300余条。流体包裹体显微观察研究表明,玲珑石英脉型金矿新鲜花岗岩和钾化花岗岩主要含有H2O包裹体,其次有少量H2O-CO2包裹体;(黄铁)绢英岩通常含较粗粒石英集合体,石英中有丰富的H2O,特别是H2O-CO2包裹体;金矿体(含金石英脉)含有明显数量的H2O-CO2包裹体;特别是存在较大的三相H2O-CO2包裹体。不同期次(世代)石英中H2O和H2O-CO2包裹体的大小、形态、相对含量和丰度变化较大。  相似文献   

17.
There are awareness and concerns caused by the decreasing sea ice coverage around the Arctic and Antarctic due to effects of climate change. Emphasis in this study was on rapid changes in Arctic sea ice coverage and its impacts on the marine ecology during the fourth Chinese National Arctic Research Expedition in 2010. Our purpose was to establish a baseline of Arctic fish compositions, and consequent effects of climate change on the fish community and biogeography. Fish specimens were col- lected using a multinet middle-water trawl, French-type beam trawl, otter trawl, and triangular bottom trawl. In total, 36 tows were carried out along the shelf of the Bering Sea, Bering Strait, and Chukchi Sea in the Arctic Ocean. in total, 41 fish species belonging to 14 families in 7 orders were collected during the expedition. Among them, the Scorpaeniformes, including 17 species, accounted for almost one third of the total number (34.8%), followed by 14 species of the Perciformes (27.0%), 5 species of the Pleuronecti- formes (22.3%), and 2 species of the Gadiformes (15.4%). The top 6 most abundant species were Hippoglossoides robustus, Bore- gadus saida, Myoxocephalus scorpius, Lumpenus fabricii, Artediellus scaber, and Gymnoeanthus trieuspis. Abundant species var- ied according to the different fishing methods; numbers of families and species recorded did not differ with the various fishing methods; species and abundances decreased with depth and latitude; and species extending over their known geographic ranges were observed during the expedition. Station information, species list, and color photographs of all fishes are provided.  相似文献   

18.
Sea surface winds from reanalysis (NCEP-2 and ERA-40 datasets) and satellite-based products (QuikSCAT and NCDC blended sea winds) are evaluated using in situ ship measurements from the Chinese National Antarctic Research Expeditions (CH1NAREs) from 1989 through 2006, with emphasis on the Southern Ocean (south of 45°S). Compared with ship observations, the reanalysis winds have a positive mean bias (0.32 m·s-1 for NCEP-2 and 0.13 m·s-1 for ERA-40), and this bias is more pronounced in the Southern Ocean (0.57 m·s-1 and 0.45 m·s-1, respectively). However, mean biases are negative in the tropics and subtropics. The satellite-based winds also show positive mean biases, larger than those of the reanalysis data. All four wind products overestimate ship wind speed for weak winds (〈4 m·s-1) but underestimate for strong winds (〉10 m·s-1). Differences between the reanalysis and satellite winds are examined to identify regions with large discrepancies.  相似文献   

19.
负载型纳米TiO_2光催化杀灭溶藻弧菌的研究   总被引:1,自引:0,他引:1  
采用平均粒径约5nm,主要结构为锐钛矿型的纳米TiO2光催化剂,以泡沫型复合镍板为载体对纳米TiO2进行固定,并对固定后的纳米TiO2杀灭溶藻弧菌的能力进行了研究。结果表明:利用高压汞灯作为光源,以泡沫型复合镍板为载体的纳米TiO2对溶藻弧菌具有较强的杀灭能力;极少量过氧化氢的加入加快了纳米TiO2的杀菌速度;因此,负载型纳米TiO2在水产病害防治方面具有广阔的应用前景。  相似文献   

20.
【目的】研究Mg2+、Mn2+对波吉卵囊藻生长和多糖代谢的影响。【方法】取蒸馏水培养数日后的波吉卵囊藻液接入以f/2培养液的配方为基础的新鲜培养液中,Mg2+浓度梯度分别设置为0、1、2、4、8 mg/L,Mn2+浓度梯度分别设置为0、0.005、0.050、0.500、5.000 mg/L,实验周期为10 d。【结果与结论】不同浓度Mg2+、Mn2+对波吉卵囊藻的生长有显著性影响,当Mg2+质量浓度为2 mg/L时,波吉卵囊藻的相对增长率、色素蛋白含量均出现最大值,显著高于Mg2+添加量为0、4和8 mg/L的组(P<0.05),当Mn2+质量浓度为0.005 mg/L时,波吉卵囊藻相对增长率、色素蛋白含量均出现最大值,显著高于Mn2+添加量0、0.050、0.500和5.000 mg/L组(P<0.05)。不同浓度Mg2+、Mn2+对波吉卵囊藻胞外多糖含量有显著影响(P<0.05),当Mg2+质量浓度>2 mg/L、Mn2+质量浓度>0.005 mg/L时,波吉卵囊藻生长均受到胁迫,其胞外多糖合成量明显增加,以保护藻体不受危害;当Mg2+质量浓度为8 mg/L、Mn2+质量浓度为5.000 mg/L时,波吉卵囊藻胞外多糖含量分别为对照组的2.43和3.36倍。  相似文献   

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