活性MgO定量分析标准方法的比较研究          下载免费PDF全文

董金美  余红发  李颖  乔宏霞  王梅娟 《盐湖研究》2011,19(2):29-33

用WB和JC标准水合法测定轻烧MgO粉的活性MgO含量,对测定结果进行方差和误差分析,并研究了水化时间对测定结果的影响。结果表明,两种方法存在显著性差异,WB和JC水合法的平均相对误差分别为1.31%和-19.85%,WB水合法精密度远高于JC水合法。以WB水合法为基准,JC水合法的平均相对误差大于-20%,远远超过行业标准中规定的±3%。因此,对于镁水泥原料MgO中活性含量的定量分析,不能采用JC方法,必须采用WB方法。此外,发现水化3 h已经接近活性氧化镁的水化平衡,为修订WB标准方法提供了参考依据。  相似文献   

Evidence for two episodes of volcanism in the Bigadiç borate basin and tectonic implications for western Turkey     

Fuat Erkül  Cahi&#x;t Helvaci  Hasan Szbi&#x;li&#x;r 《Geological Journal》2005,40(5):545-570

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Geological features and genesis of Gaotaigou borate deposit, Jilin, China     

XIAO Li-mei SUN Feng-yue 《东北亚地学研究》2005,8(1):65-71

Gaotaigou borate deposit in Ji＇an area, southeastern Jilin, is located in the easten end of Liaoning-Jilin （Liaoji） Proterozoic paleo-rift, which is a medium-sized deposit and makes up 67% of the total borate reserves in Jilin Province. The original borate ore bodies were formed by sedimentary exhalative process in Paleoproterozoic, but were activated and enriched by later metamorphism. In late stage of metamorphism, hydrothermal fluid of metamorphic origin made wallrocks be altered and the borate ore bodies be reformed. Ore bodies are strictly controlled by strata and their lithologies. In addition, the shape and spatial distribution of ore bodies are also defined by the Gaotaigou syncline. Combined with the ore-controlling factors and mineralizing features, it has been proposed that Gaotaigou borate deposit is a metamorphosed and hydrothermally altered sedimentary exhalative deposit.  相似文献   

Mg₂B₂O₅晶须增强AZ91D镁基复合材料在Cl_-溶液中腐蚀行为_*          下载免费PDF全文

王晓民  喇培清  程楚  张廷安 《盐湖研究》2017,25(3):61-66

用电化学方法测量了Mg_2B_2O_5晶须增强AZ91D镁基复合材料在3.5%NaCl溶液中的开路电位、动电位极化曲线和交流阻抗,研究了晶须体积分数对镁合金基体耐腐蚀性能的影响,并利用SEM和XRD表征了腐蚀后复合材料表面的微观形貌和相组成。结果表明,随着Mg_2B_2O_5晶须体积分数的增加,AZ91D镁基复合材料的耐腐蚀性逐渐提高。当硼酸镁晶须的体积分数为35%时,材料的自腐蚀电位提高0.2V以上,自腐蚀流密度降低了1个数量级;SEM测试表明,复合材料表面生成了一层晶须增韧的腐蚀钝化膜,对基体起到保护作用。  相似文献   

柴达木盆地小柴旦湖硼酸盐的形成   总被引：6，自引：0，他引：6  

孙大鹏 《矿物岩石》1991,11(4):57-65

本文探讨了小柴旦湖第四纪沉积物中的钠硼解石和柱硼镁石的特征和成因,并进行了盐湖卤水的模拟实验,认为硼酸盐矿物在卤水浓缩的早期到晚期均可形成。  相似文献   

大义山西北端硼矿床特征及其控矿因素     

周荣文  唐先礼 《湖南地质》1990,9(3):20-24

湖南大义山西北端的硼矿属接触交代—热液叠加型。矿体赋存于大义山花岗岩体中上石炭统壶天群白云岩接触带中,呈层状、似层状,局部为透镜状,分枝复合明显。矿石组分复杂,结构构造多样。富镁的碳酸盐岩是有利的成矿围岩;富含硼、氟的大义山花岗岩体是成矿母岩;广泛发育的节理裂隙是容矿构造。外围尚有一定的找矿远景。  相似文献   

Precipitation of aluminum and magnesium secondary minerals from uranium mill raffinate (pH 1.0–10.5) and their controls on aqueous contaminants     

《Applied Geochemistry》2016

Models of geochemical controls on elements of concern (EOCs; e.g., As, Se, Mo, Ni) in U tailings are dominated by ferrihydrite. However, the evolution of aqueous concentrations of Al and Mg through the Key Lake (KL) U mill bulk neutralization process indicates that secondary Al and Mg minerals comprise a large portion of the tailings solids. X-ray diffraction, Al K-edge XAS, and TEM elemental mapping of solid samples collected from a pilot-scale continuous-flow synthetic raffinate neutralization system of the KL mill indicate the secondary Al–Mg minerals present include Mg–Al hydrotalcite, amorphous Al(OH)₃, and an amorphous hydrobasaluminite-type phase. The ferrihydrite present contains Al and may be more accurately described as Al–Fe(OH)₃. In the final combined tailings sample (pH 10.5) collected from the model experiments using raffinate with Al, Mg, and Fe, solid phase EOCs were associated with Al–Fe(OH)₃ and Mg–Al hydrotalcite. In model experiments using raffinate devoid of Fe, aqueous EOC concentrations decreased greatly at pH 4.0 (i.e., where ferrihydrite would precipitate) and largely remained in the solid phase when increased to the terminal pH of 10.5; this suggests Al–Mg minerals can control aqueous concentrations of EOCs in the raffinate in the absence of Fe. Maximum adsorption capacities for individual and mixtures of adsorbates by Mg–Al hydrotalcite were determined. A revised model of the geochemical controls in U mill tailings is presented in which Al and Mg minerals co-exist with Fe minerals to control EOC concentrations.  相似文献   

卤水镁矿产资源开发态势计量分析          下载免费PDF全文

吕俊生  吴志坚  王臣松 《盐湖研究》2016,24(1):58-65

从专利视角出发,对全球卤水镁矿产资源开发技术的发展现状与态势进行了分析,通过专利量的年度走势、区域分布、申请人分布、IPC分布、文本聚类、主题关联等信息,展示了百年卤水镁矿产资源开发的技术概况;为了解近期卤水镁资源开发的状况,分析了近5年全球卤水镁矿产资源开发技术的专利,通过对比分析,展现了卤水镁矿产资源研发的热点与态势。  相似文献   

利用盐湖氯化镁-石灰制备硅热法炼镁用煅白的实验研究          下载免费PDF全文

祁米香  王树轩  杨占寿  王舒娅  李波  邹兴武 《盐湖研究》2016,24(1)

以盐湖副产水氯镁石为原料,与一定比例的石灰反应得到氢氧化镁和氢氧化钙的混合沉淀物,该混合物经过滤、洗涤、烘干后在一定温度下煅烧得到符合皮江法炼镁用的合成煅白。实验结果表明,该工艺是可行的,在石灰/氯化镁摩尔比2.05~2.10：1,反应时间1.5,煅烧温度为800℃,煅烧时间为60min时,合成的煅白中钙镁摩尔比： 0.95~1.07：1,煅白的平均水活度达34%,符合硅热法炼镁用中间原料煅白的参数条件。该技术可为利用盐湖氯化镁制备金属镁新工艺开发提供了数据参考。  相似文献   

论盐、碱、镁的联产问题     

周仲怀  徐丽君  刘兴俊 《海洋科学》1992,16(5):64-68

从可能性和可行性两个方面论证了盐、碱、镁的联产问题。强调了利用莱州湾沿岸地下浓缩海水和饱和盐水的预处理方法以及白泥(盐泥)的综合利用问题,并着重指出了环境问题的重要性。最后提出了盐、碱、镁联产中应注意的几个问题。  相似文献