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761.
采用石油行业径向水平喷射钻井技术在煤矿注浆堵水方面可实现水平定向射流成孔,在薄层灰岩、奥陶系灰岩承压含水层中寻找沟通裂隙,尤其在直井或分支井段较小漏水的情况下可进行多分支喷射,还可以加适量盐酸、酸化缓蚀剂进行局部酸化沟通裂隙,压裂地层,从而降低注浆压力,提高注浆堵水效果。径向水力喷射钻井在峰峰集团梧桐庄矿9号注浆孔应用取得了一定的成效。该技术也可作为地热井增大水量的一种手段。  相似文献   
762.
本文以金川铜镍硫化物精矿为研究对象,对比研究了A.f.菌浸出与硫酸酸溶浸出对铜镍硫化物精矿中有价金属Co、Ni和Cu的提取效果。为了进一步优化硫化物精矿中有价金属Co、Ni和Cu浸出效果,考察了微生物-硫酸浸出与硫酸-微生物浸出对精矿中Co、Ni和Cu提取的影响。结果表明:Co2+、Ni2+、Cu2+微生物-硫酸浸出率可分别达到85.05%、98.32%和95.31%。微生物-硫酸浸出加速了硫化物矿物的溶解,促进了硫化物矿物中有价金属Co、Ni、Cu的浸出,大大提高了有价金属Co2+、Ni2+、Cu2+的浸出率。  相似文献   
763.
黄金廷  马洪云  张俊  董佳秋  王冬 《地质通报》2015,34(11):2074-2082
土壤有效热导系数和水流通量是研究大气-土壤系统水分转化的重要变量。采用动态回归模型(DHR)获取土壤温度的振幅和相位变化,联合土壤水热耦合方程的解析解估算土壤有效热导系数和土壤水流通量,并将该方法应用于毛乌素沙地的土壤水流通量估算中。结果显示,实例研究估算获得的有效热导系数在10~(-7)m~2/s数量级变化,且随振幅比的增加呈指数增加,随相位差的增加呈指数衰减。当土壤含水率小于0.08时,有效热导系数呈线性增加;当土壤含水率大于0.08时,接近恒定值(定量0.08),土壤水流通量随土壤含水率的变化无明显的线性关系。  相似文献   
764.
赛什塘-日龙沟以铜为主的多金属矿田位于东昆仑与西秦岭的交接部位,分布有大量中酸性侵入体,与成矿作用有密切关系。通过对日龙沟锡多金属矿区花岗闪长岩LA-ICP-MS锆石U-Pb同位素和岩石地球化学研究,认为该岩体形成于中三叠世(230.7±1.5Ma),属于相对贫硅(Si O2含量为62.24%~63.67%)、偏碱(碱度率AR为1.73~1.88)、过铝(铝饱和指数A/CNK介于2.37~2.70之间)的花岗闪长岩。稀土元素总量较高(∑REE=111×10-6~164×10-6),稀土元素配分曲线呈轻稀土元素富集(LREE/HREE=9.83~16.95)的右倾曲线,(La/Yb)N介于16.5~34.32之间,Eu、Gd具有弱负异常(δEu=0.79~0.98,δGd=0.73~0.81),而Tb具有弱正异常(δTb=1.23~1.28)。微量元素显示,Rb、Ba、Th、U等大离子亲石元素相对富集,Nb、Ta、Dy、Y、Ho、Yb、Lu等高场强元素亏损。岩相学特征显示,岩体主要由斜长石、黑云母、石英及角闪石组成;镜下可见2组斜长石及包含结构。综合判断认为,日龙沟花岗闪长岩体属I型花岗岩,可能是二叠系中性火山岩部分熔融形成的。结合野外地质调查,初步认为赛什塘-日龙沟矿田具有2期成矿作用。  相似文献   
765.
森林生态系统的土壤微生物群落组成和活性,是影响生物地球化学循环、有机质代谢和土壤质量的关键因素.磷脂脂肪酸(PLFA)是一类可有效表征活体微生物群落结构的生物标志物,而其单体稳定碳同位素(δ13C)水平对土壤微生物植物碳代谢具有独特的指示作用.本次研究以土壤PLFA为对象,分析了我国位处纬度梯度带上(24°N~47°N...  相似文献   
766.
用GC/MS法分析比较了紫菜粉、小球藻、酵母、Banta液(牛粪1.5g+干稻草2g+沃土20g+水1000cm3)4种食物条件下蚤状潘的脂肪酸组成.结果表明:4种食物培养下,蚤状潘的总脂含量依次为39.80、60.10、44.60、52.30mg/g.一共检测出脂肪酸14种,其中8种饱和脂肪酸(SFA),2种单不饱和脂肪酸(MUFA),4种多不饱和脂肪酸(PUFA).紫菜粉培养组与小球藻组PUFA含量显著高于酵母组和Banta液组(P〈0.05),占总脂肪酸的1/3以上,酵母组MUFA质量分数最高(P〈0.05),达55.73%,Banta液组以SFA质量分数最高(P〈0.05),为52.45%.其中紫菜粉组的PUFA中缺乏C18:3,但C20:5(EPA)和C20:4(AA)质量分数高达22.67%和9.02%是小球藻组的1.6倍和4.5倍(P〈0.05),而且EPA和AA的实际含量也显著高于小球藻组(P〈0.05),达到9.02mg/g和3.59mg/g;比较得出,紫菜粉培养组的20碳以上必需不饱和脂肪酸含量丰富,明显高于其他3组.本实验证实蚤状潘的脂肪酸组成与食物脂肪酸成正相关.分析认为,用紫菜粉培养枝角类用于海水育苗会取得更佳的营养效果.  相似文献   
767.
We measured the concentrations of dimethylsulfide (DMS), acrylic acid (AA), and dimethylsulfoniopropionate (DMSP) during growth of three microalgae: Prorocentrum micans, Gephyrocapsa oceanica, and Platymonas subcordiformis. The DMSP, AA, and DMS concentrations in culture media varied significantly among algal growth stages, with the highest concentrations in the late stationary growth stage or the senescent stage. In the stationary growth stage, the average DMSP concentration per cell in P. micans (0.066 5 pmol/cell) was 1.3 times that in G. oceanica (0.049 5 pmol/ cell) and 20.2 times that in P. subcordiformis (0.003 29 pmol/cell). The average concentrations of AA were 0.044 6, 0.026 9, and 0.003 05 pmol/cell in P. micans, G. oceanica, and P. subcordiformis, respectively, higher than the concentrations of DMS (0.272, 0.497, and 0.086 2 fmol/cell, respectively). There were significant positive correlations between cell density and AA, DMSP, and DMS concentrations. The ratios of DMS/AA and AA/(DMSP+AA) in the three algae differed significantly over the growth cycle. In all three microalgae, the DMS/AA ratios were less than 25% during the growth period, suggesting that the enzymatic cleavage pathway, which generates DMS, was not the main DMSP degradation pathway. The changes in the DMS/AA ratio indicated that there was a higher rate of enzymatic breakdown of DMSP in the early growth period and a lower rate during senescence. In all three microalgae, the AA/(DMSP+AA) ratio (degradation ratio of DMSP) decreased during the exponential growth phase, and then increased. The variations in these ratios can approximately indicate the cleavage mechanism of DMSP at different stages of algal growth.  相似文献   
768.
To reveal spatial dynamics of silicic acid [Si(OH)4] in the poorly sampled oligotrophic western North Pacific, we investigated the surface distribution of Si(OH)4 and associated biogeochemical parameters by using an underway survey system with a highly sensitive nutrient analyzer along the 138°E transect (between 30 and 34°N) and the 155°E transect (between 10 and 35°N) during the summers of 2007 and 2008. Surface Si(OH)4 concentrations ranged from the detection limit (11 nmol L−1) to 2462 nmol L−1. High Si(OH)4 concentrations (>1000 nmol L−1) and dynamic fluctuations were generally observed north of 23°N, while consistently stable low concentrations of 415–751 nmol L−1 were observed south of 23°N. Surface nitrate+nitrite (N+N) and phosphate (PO43−) were typically depleted to <20 nmol L−1, except for PO43− in the area south of 16°N. The majority of the study area was characterized by high-Si(OH)4 and low-N+N and PO43−. However, submesoscale/mesoscale depressions of Si(OH)4 were locally observed in the cyclonic eddy fields north of 23°N. Among a total of six Si(OH)4 depressions within the eddies, a complete Si(OH)4 depletion (<11 nmol L−1) was observed on the cyclonic side near the Kuroshio axis (33.1°N, 138°E). This depletion was closely coupled with a diatom bloom, suggesting that Si(OH)4 was exhausted by diatoms. All of the Si(OH)4 depressions were selective and not accompanied by local depressions of N+N and PO43−. This unique phenomenon might be driven by biogeochemical processes such as selective Si export (Si pump), anomalous Si uptake associated with diatom physiology, and/or Si uptake supported by N2 fixation.  相似文献   
769.
The lipids and fatty acids of two coastal clams, Meretrix lamarckii and Ruditapes philippinarum, collected at 5 and 1 m of depth, and a seep clam, Mesolinga soliditesta, collected at 331 m of depth, were examined to assess their lipid physiology and trophic relationship with their diets. The major fatty acids of lipids in Mer. lamarckii and R. philippinarum were 14:0, 16:0, 18:0, 16:1n-7, 18:1n-9, 18:1n-7, 20:4n-6, 20:5n-3, and 22:6n-3, while those of Mes. soliditesta were 16:0, 18:0, 16:1n-7, 18:1n-7, 20:1n-7, 20:1n-13, 20:2n-7, 15 (Δ5,13-20:2), and 22:2n-7,15 (Δ7,15-22:2). The major polyunsaturated fatty acids (PUFAs) in the Mer. lamarckii and R. philippinarum lipids consisted of various n-3 and n-6 long-chain (LC) PUFAs, such as 20:4n-6, 22:4n-6, 20:5n-3, 22:5n-3, and 22:6n-3, while those in Mes. soliditesta muscle and viscera included various n-4 family PUFAs (18:3n-7, 18:4n-4, 20:2n-7, and 20:3n-7) with limited kinds of n-3 and n-6 PUFAs (20:4n-6 and 20:5n-3). These findings indicate that, like other common shallow-water clams, Mer. lamarckii and R. philippinarum ingest phytoplanktonic n-3 and n-6 LC-PUFAs, whereas Mes. soliditesta utilizes limited kinds of n-3 and n-6 LC-PUFAs. In contrast to the other two bivalves species, Mes. soliditesta yielded various n-4 and n-7 (n-4/n-7) PUFAs, which were assimilated from the chemosynthetic symbionts. The high diversity of PUFAs contained in the Mes. soliditesta lipids (n-3, n-4 family, and n-6 PUFAs) suggests that this species mixotrophically utilized both photosynthetic products and vent chemosynthetic nutrition derived from geothermal energy.  相似文献   
770.
广丰县李家膨润土矿床赋存于白垩系上统南雄组第二岩性段酸性火山岩的顶底部。膨润土的主要矿物成分为蒙脱石,矿石结构构造与成矿原岩有关。矿石化学成分与酸性熔岩相近,矿体形态及空间分布受酸性熔岩流相带的控制。因此认为,膨润土矿床成矿原岩为酸性玻质熔岩,矿床是由酸性玻璃质熔岩经水解脱玻化而形成,其成因类型为风化淋滤蚀变岩型矿床。膨润土可自然改型,由原来的钠基膨润土改型成钙基膨润土和偏镁的钙基膨润土。对时代较新的酸性火山岩,在玻质熔岩发育处都有可能找到有利用价值的膨润土矿。由于膨润土常由珍珠岩、沸石脱玻化形成,三者常共生出现,是很好的找矿标志。  相似文献   
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