Effects of Operational Parameters on Decolorization of C. I. Acid Red 88 by UV/H2O2 Process: Evaluation of Electrical Energy Consumption

In the present study, effects of operational parameters on the electrical energy consumption for photooxidative process (UV/H₂O₂) for the decolorization of C. I. Acid Red 88 (AR88) have been investigated. In a series of experiments, 20 mg L^?1 of AR88 solution were irradiated in the presence of different concentrations of H₂O₂ (to find out optimum amount of H₂O₂) by UV light intensity of 30 W m^?2 for certain irradiation times. The decolorization of the dye followed pseudo first‐order kinetics, and hence, the figure‐of‐merit electrical energy per order (E_EO) is appropriate for estimating the electrical energy efficiency. The electrical energy consumption was determined during the variation of some parameters such as initial H₂O₂ concentration, initial dye concentration, UV light intensity, pH, and the gap size of solution. Results showed that electrical energy could be reduced by optimizing operational parameters.     

The spatial characterization of turbulence around large roughness elements in a gravel-bed river

This study characterizes the flow field above and around multiple instream submerged cobbles, boulders, and pebble clusters in order to obtain a better understanding of the hydrodynamics associated with large roughness elements (LREs) in gravel-bed rivers. Spatially distributed high frequency, three-dimensional velocity measurements were recorded in situ using acoustic Doppler velocimeters at different flow stages. The spatial distributions of turbulent kinetic energy, k_e, longitudinal component integral timescales, ITS_u, and Reynolds shear stresses were characterized and are presented for selected sites. The longitudinal–vertical Reynolds shear stress increased with flow stage more strongly than the longitudinal–lateral or lateral–vertical Reynolds shear stresses and dominate at the highest measured flows. Canonical redundancy analysis was used to relate LRE morphometrics and mean flow conditions to the turbulence parameters estimated in the LRE wakes (i.e., k_e, ITS_u, and Reynolds shear stresses). LRE size and mean unobstructed velocity explained the highest proportion of the variance in the turbulent wake statistics. Multivariate regression models based on LRE width, mean unobstructed longitudinal velocity and flow depth are presented offering a tool to predict LRE wake turbulence.     

Geochemistry of Archean Radioactive Quartz Pebble Conglomerates and Quartzites from western margin of Singhbhum-Orissa Craton,eastern India: Implications on Paleo-weathering,provenance and tectonic setting

Lenses of radioactive Quartz Pebble Conglomerates (QPC) and associated quartzites are exposed along western margin of Archean Bonai Granite in Singhbhum-Orissa Craton, eastern India intermittently spreading over a strike length of 8–10 km. QPCs are radioactive while quartzites are mostly non-radioactive in nature. The purpose of the research is to investigate and characterize the radioactive QPC and quartzites geochemically to decipher their paleo-weathering conditions, provenance characteristics and possible tectonic setting of deposition. Geochemical data suggest moderate to high chemical weathering conditions in the provenance areas of QPC and quartzites. Major, trace and REE data indicate predominantly felsic to partly mafic-ultramafic sources for the deposition of radioactive Quartz Pebble Conglomerates from the surrounding Archean terrain.Elevated values of Th, U, Pb, La, Ce, Y and low Sc with high critical trace elemental ratios of Th/Sc, La/Sc, Th/Cr and Zr/Sc in radioactive QPC indicate their derivation from felsic igneous source. Low concentration of Th and Sc in quartzites compared to QPC and their variable Th/Sc ratios indicate both felsic and mafic sources for quartzites, albeit their preferential felsic affiliation. Higher Cr/Th ratios in quartzites (18.4), moderate Cr/Th in QPC (5.42), low to moderate Y/Ni in QPC (0.36–12.4) and quartzite (0.29–1.88), along with Au ranging from 30 to 1527 ppb, Pt up to 188 ppb and 682 ppb in QPC and quartzites respectively point towards some contribution from mafic-ultramafic source as well. REE patterns and in particular negative Eu anomalies for both QPC and quartzites further support their derivation from felsic rocks and could possibly linked to some of the phases of Archean Singhbhum Granite and Bonai Granite. Granitic to pegmatitic source for QPC is also revealed by the presence of rounded to sub-rounded monazite, zircon and thorian-uraninite grains in their matrix. Study indicates that QPC and quartzites were deposited in a passive margin tectonic setting developed during Archean between a span of 3.3 and 3.16 Ga along the western margin of Bonai Granite when the reducing condition was prevalent as indicated by their low Th/U ratios (<4.0) and presence of detrital grains of uraninite and pyrite in QPC. Radioactive QPC from western margin of Archean Singhbhum-Orissa Craton bears broad resemblance with QPC from Witwatersrand basin of South Africa and Elliot Lake, Canada and thus appears to be ideal sites for exploring QPC hosted U (+Au-PGE) mineralization in the analogous areas.     

和田玉、玛纳斯碧玉和岫岩老玉（透闪石玉）的X射线粉晶衍射特征

软玉主要是指透闪石阳起石铁阳起石系列中的低铁富镁端员的隐晶矿物集合体,矿物的名称常以其Mg/(Mg+Fe2+)值来区分,即该比值大于0.9时为透闪石(和田玉),比值为0.9～0.5时为阳起石(玛纳斯玉).对于产于新疆、辽宁(岫岩老玉)和青海的17件软玉样品进行了X射线粉晶衍射分析,确定其主要矿物成分均为透闪石,杂质矿物很少,衍射峰位与FeO含量之间的关系不明显,衍射峰形的弥散反映组成矿物的结晶程度和粒度变化.     

红外光谱-拉曼光谱无损检测技术对透闪石和阳起石鉴定特征的研究

透闪石属于角闪石族矿物,与阳起石构成完全类质同象,有关透闪石和阳起石的红外光谱和拉曼光谱的特征差异还未见有报道。本文以外观特征相似的5件广西大化黑青色阳起石样品和2件新疆塔县青玉样品为研究对象,在前期矿物成分测试的基础下,采用红外光谱和拉曼光谱进行测试和对比分析。结果表明,阳起石的红外光谱和拉曼光谱都表现为闪石类矿物的特征峰,与透闪石的特征峰存在细微差异,漫反射红外光谱的差异特征是鉴别两者最准确、快速、无损的依据,并且适用于任意形状的样品,符合珠宝玉石饰品实验室检测领域的要求,可为和田玉的分类分级和产地鉴别等提供科学依据。按照GB/T 16552-2017与GB/T 16553-2017规定,广西大化黑青色阳起石可定名为和田玉。     

韩国软玉的宝石学特征研究

近年来市场上出现的韩国软玉具有一定的宝石学价值和商业价值。在对当地区域地质进行一定了解的基础上,通过市场调研及运用现代测试方法对韩国软玉的矿物成分、化学成分和宝石学性质进行了较为系统的研究。通过显微镜下观察,韩国软玉的主要矿物成分为透闪石,含量在98%左右,交代残余结构明显,但仍以毛毡状变晶结构为主。电子探针分析结果显示:韩国软玉在化学成分上与理论值较接近。运用X射线粉晶衍射仪对韩国软玉分析表明,主要矿物成分为透闪石,其各项参数指标与标准透闪石接近,含有少量方解石、蛇纹石,结晶度较好。韩国闪石玉矿床初步推断为花岗岩与白云质大理岩的接触交代矿床,这一观点与传统的新疆和田玉玉石矿床相似。     

和田玉（透闪石玉）的研究

用电子探针、X射线衍射、扫描电镜等测试方法,对新疆和田玉进行了研究,结果表明和田玉的主要矿物组成为透闪石,主要结构为毛毡状结构.本文还论述了其成因,指出了进一步找矿及考古意义.     

西安高新正信大厦采用CFG压灌桩基础工程实录

介绍了西安地区高层建筑采用CFG压灌桩的工程实例。以往设计对类似地质条件的高层建筑,多采用桩径800mm,桩长约40m左右的灌注桩,施工难度大,周期长,基础造价高。本工程设计将CFG压灌短桩成功应用于25层以上的高层建筑,该工法施工速度快,难度小,造价低,质量好,为类似建筑工程利用地基浅部硬持力层,充分发挥地基潜力,开创了先例。     

和田玉

通过对和田玉的矿物成分、矿床成因类型、产状序列特征比较系统地介绍,总结了当前市场上和田玉与相似软玉的肉眼鉴定要点。