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101.
王康年  吴文刚  王云  黄烨  杨秋平 《贵州地质》2021,38(1):92-98, 108
本文提出的"基于空三模型实现非接触式实测地质剖面解决方案",是通过导出空间三维模型剖面多段线三维坐标,使用自主开发的辅助软件,在AutoCAD中快捷生成剖面图。通过实践,该方案能快速完成无需人工到实地进行实测的实测剖面工作,尤其危岩体勘查中能精确反映高陡崖区微地貌起伏形态和结构面特征,解决了人工实测无法完成的工作。  相似文献   
102.
Cr K-edge XANES spectra were obtained for a variety of Cr-bearing model compounds containing Cr(II), Cr(III), Cr(IV), Cr(V) and Cr(VI), in which the Cr-site symmetry is D4h, Oh and Td. The centroid position of the pre-edge feature is a better indicator of the Cr valence than the edge position. In Cr-rich oxides, higher-energy transitions must be excluded in order to refine a robust valence for Cr. The pre-edge for chromates is not unique and varies as a function of the CrO4 2? moiety distortion, which is often related to Cr-polymerization (monochromate vs. dichromate). Both the analogy with the Mn K-pre-edge information and ab initio FEFF calculations of the pre-edge feature for Cr(III) and Cr(VI) confirm the experimental trends. This methodology is applied to the Cr K-edge pre-edge feature collected in gems (emerald, spinel and ruby), the layered minerals fuchsite and kämmererite, two Cr-bearing aqueous solutions and a set of sodo-calcic silicate glasses used for bottling sparkling white wine. In emerald and fuchsite, the Cr-site is differently distorted than its ruby or spinel counterpart. In a Cr(III)-bearing aqueous solution and sodo-calcic glass, no evidence for Cr(III) with Td and C3v symmetry is detected. However, minor amounts of chromate moieties (most likely monomeric) are detected in a glass synthesized in air. Preliminary spectra for the wine bottle glass suggest that only trace amounts of chromates might possibly be present in these glasses.  相似文献   
103.
准噶尔盆地陆东-五彩湾地区石炭系具有良好的勘探前景,该地区石炭系烃源岩有机质丰度较高,成熟度范围宽,主要处于成熟-高成熟演化阶段,主要由Ⅲ型有机质组成。在对烃源岩样品进行常规评价的基础上,用开放体系进行了热解实验和动力学模拟,对陆东-五彩湾地区的生烃特征进行了研究,尝试了高成熟烃源岩生烃过程研究及Ⅲ型干酪根液态烃排烃时间的估计,并对石炭系地层产烃率进行了计算。结果显示,陆东-五彩湾地区石炭系最早在二叠纪(距今264 Ma左右)开始生烃,后期由于地层抬升,在古近纪早期(距今61 Ma左右)结束生烃。下石炭统产烃率大,液态烃排出时间估计在距今232~196 Ma之间;上石炭统产烃率较小,液态烃排出时间估计在距今196~178 Ma 之间,但天然气生成相对较晚,有利于天然气的保存。天然气可能主要来源于上石炭统烃源岩。  相似文献   
104.
The sphalerite oxidative kinetics under hypergene condition was simulated and studied by means of a mixed flow reactor over a pH range of 1.0 7.8,and at dissolution temperatures from 20 to 55℃,ferric ion concentrations from 1.0×10-5 to 1.0×10-2 mol/L,O 2 flux of 0.5 L/min,and oxidants of ferric ion and O 2.It is indicated that with ferric ion as oxidant,the oxidation rate of sphalerite increases with increasing ferric ion concentration,temperature and decreasing pH value,and under the studied conditions,the dissolution rates of Zn and Cd are approximately identical,with the values of activation energy being 41.75 and 42.51 kJ·mol-1,respectively,suggesting that the oxidation rate of sphalerite is controlled by chemical reactions on mineral surface.However,with O 2 as oxidant,the oxidation mechanism of sphalerite varies with pH value.Oxidation rate decreases with increasing pH value when pH is lower than 5.95,whereas the increase of pH value results in an increase in oxidation rate when pH value is higher than 7.The oxidation rate of sphalerite can be expressed as:R Zn =10 1.1663 [Fe3+] 0 0.154 ·[H+] 0.2659 ·e-41.75/RT or R Cd =10 1.7292 [Fe3+] 0 0.170 ·[H+] 0.2637 ·e-42.51/RT  相似文献   
105.
通过对水中含有微量氯苯的吸附特性研究,考察β-环糊精交联聚合物吸附氯苯的动力学、热力学及连续运行条件下的稳定性和再生性能。实验结果表明:β-环糊精交联聚合物吸附氯苯的过程符合准二级动力学模型,即化学吸附是吸附过程的控制步骤;β-环糊精交联聚合物上的等温吸附符合Langmuir吸附等温模型。在15、25、35℃时最大吸附量分别为23.36、28.17、27.85mg/g;动态模拟实验中,当氯苯质量浓度为10mg/L时,氯苯的去除率大于80%。乙醇作为溶剂可以使吸附饱和的β-环糊精交联聚合物再生。  相似文献   
106.
The leaching of coal and coal/asphaltite/wood-ashes in sulfuric acid (pH 1.0, 25 °C, S/L, 1:10) was studied as a function of time; acid consumption and extracted metal concentrations are presented. Whole coals consumed acid rapidly during the first few minutes, followed by slow acid consumption. Wood-, lignite-, and asphaltite-ashes consumed acid in two stages, the rapid phase extending < 30 min and the slow phase extended up to 10 days. The rapid phase was dominated by the dissolution of Ca, K and Mg ions for wood-ash, by Ca, Al and Mg ions for lignite-ash and Ca and Mg ions for asphaltite-ash. The sulfur concentration in solution and the concentrations of Ca, Fe, K, Mg, Na, P, Al and Mn in the aqueous phase verified the neutralizing capacity of the untreated ashes as well as the formation of insoluble sulfates in the residues. The slow phase kinetics differed for different fuels and exhibited leaching of several abundant elements—Fe, Al, K, Na and Mn. Trace elements (Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, Th, U, V, Zn) sometimes required up to 32 h for maximal extraction from ashes. Suggestions are presented regarding the chemical nature of trace elements in the untreated coals and ashes and suitable residence times for economical industrial processes. We think it possible to combine bacteriological oxidation of sulfidic concentrates of acid leaching from ash of various qualities or even whole coals.  相似文献   
107.
钟翼  许建新  韩积斌  徐凯 《盐湖研究》2020,28(1):112-122
为了解阿拉尔河悬浮物对铀的吸附特性,通过静态吸附实验,研究了吸附时间、pH值、温度和铀初始浓度等因素对模拟含铀水中U(VI)去除率的影响,并从热力学和动力学方面对吸附过程进行了分析。结果表明,在T=25℃,溶液初始pH=7,接触时间为16 h时,悬浮物对铀的平衡吸附率最佳,为95.48%。随着铀初始浓度的增加,吸附量增加,但吸附率随之下降,升高温度有利于铀的吸附。铀在悬浮物上的吸附过程符合Langmuir等温吸附方程,说明悬浮物对铀为单分子层吸附,且化学吸附占主导地位。吸附动力学过程可用准二级吸附动力学模型描述,表明吸附主要受动力学控制,由两个以上步骤共同控制。FTIR和EDS分析结果表明,吸附过程中铀主要与悬浮物表面活性基团螯合并以表面络合吸附为主。吸附前后的能谱对比分析表明,吸附过程中存在离子交换行为。因此,悬浮物对铀的吸附机理是以表面络合吸附和离子交换为主、物理吸附为辅的混合吸附过程。  相似文献   
108.
It is a special petroleum geological phenomenon that Silurian oilsands are extensively distributed in the central and northeast Tarim basin. Some geochemical studies of the oilsands have been carried out, but there is still great controversy over the hydrocarbon-regenerating potential of oilsands and the possibility of Silurian oilsands as hydrocarbon source rocks. In this study, the kinetics of asphaltenes pyrolysis was directly used to simulate the potential of Silurian oilsands for regenerating hydrocarbons. According to the experimental results, combined with other related organic geochemical analysis, it is considered that Silurian oilsands in the Tarim basin have a high hydrocarbon-regenerating potential and are latent hydrocarbon source rocks.  相似文献   
109.
 The kinetics of the dehydroxylation of chrysotile was followed in situ at high temperature using real-time conventional and synchrotron powder diffraction (XRPD). This is the first time kinetics parameters have been calculated for the dehydroxylation of chrysotile. The value of the order of the reaction mechanism calculated using the Avrami model indicates that the rate-limiting step of the reaction is a one-dimensional diffusion with an instantaneous nucleation or a deceleratory rate of nucleation of the reaction product. Hence, the rate-limiting step is the one-dimensional diffusion of the water molecules formed in the interlayer region by direct condensation of two hydrogen atoms and an oxygen atom. The calculated apparent activation energy of the reaction in the temperature range 620–750 °C is 184 kJ mol−1. The diffusion path is along the axis of the fibrils forming the fibers. The amorphous or short-range ordered dehydroxylate of chrysotile is extremely unstable because forsterite readily nucleates in the Mg-rich regions. Moreover, it is less stable than the dehydroxylate of kaolinite, the so-called metakaolinite, which forms mullite at about 950 °C. This difference is interpreted in terms of the different nature of the two ions Mg2+ and Al3+ and their function as glass modifier and glass-forming ion, respectively. Received: 10 April 2002 / Accepted: 7 January 2003 Acknowledgements This work is part of a COFIN project (04 Scienze della Terra, NR 17, 2000) supported by MURST. Dr Dapiaggi is kindly acknowledged for help during the data collection at the Dipartimento di Scienze della Terra, University of Milan.  相似文献   
110.
含钒石煤是我国一种新类型钒矿资源,钒的氧化是石煤提钒的基础。本文对钒的氧化动力学作了初步工作,通过试验数据处理结果表明,采用Ерофеев综合动力学公式:描述石煤中钒的氧化过程:2VO2固+1/2O2=Y2O5固简明可行,较为适宜。 钒氧化反应初期阶段以动力学方式进行:n1=1,属一级反应过程;继之,n2=0.2,反应受扩散制约。测定了由动力学过程转换为扩散过程所需的反应时间及其钒氧化率,计算了这两种过程的速率常数和表观活化能。  相似文献   
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