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11.
新疆罗布泊地区水硝碱镁矾和钠硝矾的矿物学研究   总被引:3,自引:0,他引:3  
蔡克勤  高建华 《矿物学报》1992,12(2):143-151,T001
本文报道了我国新发现的两个硝酸盐-硫酸盐复盐矿物——水硝碱镁矾和钠硝矾。水硝碱镁矾呈假四方双锥状,属三方晶系,解理{0001}完全,一轴负晶,折光率为ω=1.474,ε=1.436:晶胞参数α=1.0894nm,c=2.4396nm,粉晶图的强衍射线为:2.813(100),8.096(19)1.991(18),3.391(10),2.199(8),8.751(8)。钠硝矾为板状,板柱状,解理{010}完全,{100}不完全。聚片双晶平行(100),二轴负晶,折光率为:α=1.487,β=1.481,γ=1.391;-2V=28°。矿物属单斜晶系,晶胞参数为:α=1.0565nm,b=0.6922nm,c=0.5194nm。粉晶图的强衍射线为:10.3(100),3.46(35),2.594(30),2.871(30),2.856(30),4.13(20)。文中还列出了两矿物的差热和红外吸收光谱等资料。  相似文献   
12.
Through a systematic observation of water level and temperature, and a comprehensive analysis of the data on major/trace elements, nitrite, hydrogen-oxygen isotopes, the conclusion has been drawn that there are two relatively independent groundwater systems (cool water and hot water), and the geochemical indicators of hot/cool waters are described. The cool water system is relatively enriched in Ca2 , Mg2 and HCO3-. Its TDS is relatively low, about 1400–1800 mg/L. The hot water system is relatively enriched in K , Na , Cl- and SO42-. Its TDS is relatively high, about 2200–2300 mg/L. The cool water system is enriched in Ba, Ga, Cd, and the hot water system is enriched in B, Ti, Cr, Ni, Cu, Mo, Rb, and Cs, relatively. Especially, the contents of Rb and Cs in the hot water system are more than five times as high as those in the cool water system. The NO3- contents of cool water discharged from the gold mine are relatively high, and those of hot water are extremely low. The δD and δ18O values follow an increasing order of surface water>mine cool water>mine hot water. The cool water comes mainly from the lateral supply of phreatic water, while the hot water comes mainly from the vertical supply of deeply circulating structure-fracture water. The ratio of cool water over hot water was estimated to be about 1:1 by a water quality model..  相似文献   
13.
岩溶含水层的极不均一性特征使岩溶水溶质运移受构造、裂隙空间及其发育方向控制;因环境条件复杂,开展岩溶水污染原位修复技术难度较大,截止目前,国内尚未系统地开展岩溶含水层水污染原位修复研究工作。文章选择鲁中南山区典型岩溶发育及硝酸盐污染地段,施工组合钻孔建设修复试验工程,采用“乙醇+葡萄糖”液态碳源和“聚乙烯醇+淀粉颗粒”固态反应器分别进行岩溶水硝酸盐污染原位修复试验。结果表明:浓度500 mg?L-1、1 000 mg?L-1的“乙醇+葡萄糖”反硝化溶液对硝酸盐浓度的降解率分别为6.45 %和21.52 %;单位长度组成材料“聚乙烯醇3 kg+淀粉颗粒3 kg”、“聚乙烯醇2 kg+淀粉颗粒4 kg”的两种反硝化固态反应器对硝酸盐浓度的降解率分为33.91%和34.96%。试验证明在裂隙型岩溶地区采用孔组方案进行地下水污染原位修复技术可行、且能取得较显著效果。修复工程布设方式和试验成果对类似地区开展岩溶地下水污染原位修复具一定借鉴意义。   相似文献   
14.
为了深入认识库米什盆地硝酸盐矿床成矿离子的空间分布特征、表层沉积物中硝酸盐含量较高的原因,以盆地硝酸盐矿床为研究对象,开展研究区内各类补给水样和沉积物样可溶性盐类物质化学组成的定量分析研究;结合野外地质踏勘工作,探讨研究区硝酸盐矿床成矿离子的迁移规律,初步建立盆地硝酸盐矿床沉积成矿作用模型.结果表明,K+、Na+、NO...  相似文献   
15.
Nitrite oxidation in the tropospheric aqueous phase by freezing was evaluated by freezing a field sample. Nitrite oxidation by dissolved oxygen in the freezing process is much faster than by other oxidation processes, such as reactions with ozone, hydrogen peroxide or dissolved oxygen in an aqueous solution at pHs 3 to –6. At pH 4.5 and 25°C, the lifetime of nitrite in the aqueous phase is ca. 1 hr in oxidation by ozone (6×10-10 mol dm-3), ca. 10 hr in oxidation by H2O2 (2×10-4 mol dm-3), and 7.5 hr (Fischer and Warneck, 1996) in photodissociation at midday in summer. Under the same conditions at a temperature below 0°C, the lifetime of nitrite in the freezing process is estimated as ca. 2 sec when the droplets are frozen within a second. The reaction by freezing is affected by the presence of salts, such as NaCl or KCl, or orgnaic compounds, such as methanol or acetone. The results of freezing a field rain or fog sample showed that nitrite oxidation proceeds below pH 6, and the conversion ratio of nitrate from nitrite increases with decreasing pH. The oxidation of nitrite by freezing was also observed in freezing fog particles generated by an ultrasonic humidifier. The ratios of the concentrations of ions in the winter sample to those in the summer sample (or those in the fog sample) were almost the same values. However, the concentration of nitrite in the winter sample was lower than that estimated by the ratios of other ions. From the present study, it seems that the freezing process plays an important role in the nitrite sink process in the tropospheric aqueous phase.  相似文献   
16.
A partial balance of mineral N is given for the basins of two coastal rivers in a forest zone in the Ivory Coast. The dry and wet depositions on the basin surfaces is given for particulate matter (NO3 , NH4 +). The quantity of mineral N washed away in the rivers is evaluated. The losses from leaching of the soils by rainwater are about 0.33 to 1.0% of the atmospheric depositions for NH4 +–N and 2.2 to 5.8% for NO3 –N. The yearly atmospheric input of N compounds to the ecosystem, about 1.4 g N m–2 y–1, is at least 14% of mineral N formed in the soils and is therefore quite significant.  相似文献   
17.
A global 3-D Lagrangian chemistry-transport model STOCHEM is used to describe the tropospheric distributions of four components of the secondary atmospheric aerosol: nitrate, sulphate, ammonium and organic compounds. The model describes the detailed chemistry of the formation of the acid precursors from the oxidation of SO2, DMS, NOx, NH3 and terpenes and their uptake into the aerosol. Model results are compared in some detail with the available surface observations. Comparisons are made between the global budgets and burdens found in other modelling studies. The global distributions of the total mass of secondary aerosols have been estimated for the pre-industrial, present day and 2030 emissions and large changes have been estimated in the mass fractions of the different secondary aerosol components.  相似文献   
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19.
本文采用石墨炉原子吸收光谱法测定地球化学样品中痕量银。选择硝酸镁和硫脲混合溶液为基体改进剂,银的灰化温度为800℃,研究了最佳的分析测定条件。该方法检出限为0.01μg/g。用该方法对国家地球化学标准样品的测定结果与标准值相符。  相似文献   
20.
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