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本法用BF7电极作指示电极,双液接饱和甘汞电极作参比电极,用十六烷基三甲基氯化铵(CETAC)或氯代十六烷在吡啶(CPC)电位滴定用水提取的复合推进剂中的高氯酸铵。共平均回收率达99.75%,准确度和精密度中和法(甲醛法)。 相似文献
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在氟硼酸废水治理研究中,探讨了常规钾盐沉淀法从低质量浓度BF4-废水中回收BF4-的可行性,在常规钾盐沉淀法回收BF4-条件研究基础之上,提出采用晶析法回收废水中的BF4-,使BF4-回收率>73%(绝对回收率理论值为76.9%).研究了晶种加入量、反应时间、pH等对BF4-回收率的影响,解决了KBF4分离难的问题. 相似文献
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Isotropic Negative Area Compressibility over Large Pressure Range in Potassium Beryllium Fluoroborate and its Potential Applications in Deep Ultraviolet Region 下载免费PDF全文
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Mohamed A. Abd-Alla Ferial M. Atta Maisa E. Abd-Elmonem Saoud A. Metwally 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1988,43(2):91-94
Interaction of antipyrine (I) with nitrous acid in the presence of excess sodium nitrite as buffer, followed by the addition of fluoroboric acid afforded the direct and short way to synthesis of antipyrine-4′-diazonium fluoroborate (II). Pyrolysis of (II) at 165°C gave 4′-fluoroantipyrine (III). The structure of (III) was determined by IR and 13C NMR analyses. 相似文献
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以卤水和氟硼酸钠为原料,反应制备出氟硼酸钾固体,再以浓硫酸和氟硼酸钾反应,制备出硫酸钾。在制备氟硼酸钾步骤中,以氟硼酸钠添加量、反应温度、反应时间为变量;在氟硼酸钾与浓硫酸反应步骤中,以浓硫酸添加量、反应温度、反应时间为变量,通过单因素变量法探索出该工艺海水提钾并制备硫酸钾的最佳条件,即提钾过程中BF4-与K+摩尔比为1.13∶1,反应温度10℃,时间30 min,此条件下钾离子回收率可达92.8%,通过XRD检测可知,沉淀成分为氟硼酸钾。制备硫酸钾过程中,浓硫酸与KBF4摩尔比为0.697∶1,反应温度600℃,时间90 min。该工艺钾提取率较高,所用试剂氟硼酸钠能回收再利用,为我国卤水提钾以解决钾资源缺乏问题开辟了新的思路。 相似文献
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D.Umamaheswari B.C.Jamalaiah T.Sasikala G.V.Lokeswara Reddy L.Rama Moorthy 《中国稀土学报(英文版)》2012,30(5):413-417
Spectroscopic and fluorescence properties of Nd 3+ ions in sodium fluoroborate(SFB) glasses were prepared and characterized through optical absorption,emission and decay measurements.The energy level analysis was carried out using free-ion Hamiltonian model.Experimental oscillator strengths were determined by measuring the area encompassed by the absorption peaks recorded for 1.0 mol.% Nd 3+-doped glasses.The Judd-Ofelt parameters(2,4,6) were used to evaluate the laser characteristic parameters such as radiative transition probability(A R),radiative decay time(τ R),fluorescence branching ratio(β R) and stimulated emission cross-section(σ e) for the 4 F 3/2 metastable state.The fluorescence spectra for different concentrations of Nd 3+ ions were recorded by exciting the samples at 514.5 nm Ar + ion laser. 相似文献