东天山卡拉塔格矿集区奥陶—志留纪侵入岩地球化学特征及成因

卡拉塔格矿集区位于东天山大南湖岛弧带,大量古生代岩浆岩的发育,在研究东天山古生代弧盆演化上具有天然优势。本文对矿集区内侵入岩进行地球化学研究,结果表明,区内侵入岩表现出低-中钾、富钠、过铝质、钙碱性特征,富集Rb、Ba、K等大离子亲石元素,而亏损Nb、Ta、P等元素;ε_(Nd)(t)为正且稳定,Isr变化大,t_(2DM)较年轻;闪长岩和花岗闪长岩LA-ICP-MS锆石U-Pb加权平均年龄为(449. 9±3. 6) Ma和(435. 5±3. 4) Ma。综合分析认为,区内侵入岩皆为成熟岛弧产物,岩浆来源可能为地幔,为流体上升交代地幔楔橄榄岩发生部分熔融而形成。Sr-Nd同位素暗示基底可能存在古地壳,但影响极其有限。岩石年代学表明俯冲活动从奥陶纪就已开始,大南湖—头苏泉岛弧带是康古尔洋向北俯冲的产物。     

薄壁金刚石钻头的研制和在电熔锆刚玉耐火材料中的应用

电熔锆刚玉砖具有高硬度、耐高温、耐磨损、抗腐蚀等特点,因而成为玻璃熔窑的关键筑炉材料。文章通过复合电镀方法研制和生产薄壁金刚石钻头。在研制过程中,对金刚石钻头的胎体配方进行了优化,确定了电镀工艺参数,分析了金刚石参数等对钻进过程的影响,采用混目金刚石扩大了钻头的适用范围,提高了钻头的自锐性。研制的电镀薄壁金刚石钻头用于钻进锆刚玉砖耐火材料,其平均使用寿命达到6m,钻进时效为1.5m。使用结果表明:胎体配方、工艺流程和电镀参数是合理的,电镀金刚石薄壁钻头是最适合钻进电熔锆刚玉砖的金刚石工具,加工后的锆刚玉砖具有精确的几何形状和高光洁度的表面。     

GPC精铸面砂的应用

由于优质面层材料锆英砂的短缺及其价格的不断上涨,寻找面层错英砂的替代品成为一种必然趋势.主要介绍了采用淮北煤系高岭土开发的精铸面砂,部分替代面层锆英砂在精铸行业上的应用.结果表明,该砂可以用于碳钢、低合金钢以及铝、铜等有色合金和部分不锈钢铸件的生产.     

Genesis of the high gamma sandstone of the Yanchang Formation in the Ordos Basin, China

Recently, more attention has been paid on the high gamma sandstone reservoirs of the Yanchang Formation in the Ordos Basin, China. These high gamma sandstones have logging characteristics different from conventional sandstones, which influences the identification of sandstone reservoirs. Zhang et al (2010) proposed that the high gamma sandstones of the Yanchang Formation might be the result of re-deposition of homochronous sedimentary tuffs or previous tuffs as a part of the sandstone. However, we present a different viewpoint: 1) few tuffs or tuff debris have been found in the high gamma sandstones of the Yanchang Formation; 2) high gamma (or high Th content) sandstones of Yanchang Formation are not related to either clay minerals or feldspar; 3) the heavy minerals in the sandstone reservoirs of the Yanchang Formation are dominated by zircon, which is characterized by abnormally high Th and U contents, up to 2,163 ppm and 1,362 ppm, respectively. This is sufficient to explain the high gamma anomaly. The conclusion is that the high gamma value of the Yanchang Formation sandstones might be caused by zircon with high Th and U contents in sandstones rather than from the tuff components.     

纳米硅酸锆的水热合成

利用水热法制备了纳米ＺｒＳｉＯ４粉体,借助ＸＲＤ,ＴＥＭ及ＳＥＭ等研究了ＺｒＳｉＯ４晶粒相相成,粒度和结晶形貌与前驱物Ｚｒ和Ｓｉ的摩尔比,水热反应温度以及反应时间之间的关系,并对ＺｒＳｉＯ４的合成机理进行了初步研究。     

锆英石陶瓷生产工艺对力学性能的影响

对锆英石陶瓷的生产工艺对材料的显微结构、力学性能的影响进行了研究.结果表明:造粒粉颗粒的硬壳与空洞在坯体中形成大颗粒,如果在成型过程中末被完全破坏遗留在烧结体中而引起材料内部气孔的存在,使材料的力学性能明显下降.制定合理的锆英石材料生产工艺、控制气孔的产生,是提高材料强度和可靠性的有效措施.     

锆英石陶瓷生产工艺对力学性能的影响

对锆英石陶瓷的生产工艺对材料的显微结构、力学性能的影响进行了研究.结果表明:造粒粉颗粒的硬壳与空洞在坯体中形成了颗粒,如果在成型过程中末被完全破坏,遗留在烧结体中而引起材料内部气孔的存在,材料的力学强度和可靠性能明显下降.制定合理的锆英石材料生产工艺、控制气孔的产生,是提高材料强度和可靠性的有效措施.     

祁连—秦岭造山带交接部位25亿年 碎屑锆石的发现及其地质意义

对来自祁连与秦岭造山带交接部位秦安地区葫芦河流域的“葫芦河群”浅变质砂岩中大量碎屑锆石的 LA-ICP-MSU-Pb测年结果发现,其中含有年龄为2302～2578Ma的锆石颗粒。这些锆石年龄均十分谐和,且 阴极发光图象上显示具有典型岩浆型振荡环带结构和岩浆成因锆石的w(Th)/w(U)为0.11～1.42,表明这些 锆石为新太古代末期构造岩浆作用的产物。这些锆石是该区域迄今发现的最古老的锆石,表明祁连与秦岭造山 带交接部位可能存在比陇山岩群和秦岭岩群更古老的陆壳。     

镁锆质浇注料的抗渣性研究

采用坩埚法研究了镁锆质浇注料的抗渣性.结果表明:随着配料中锆英石的增加,浇注料抗渣渗透性增强,抗渣侵蚀性降低.文中主要探讨了镁锆质浇注料抗渣渗透性机理.     

Thermal barrier coating application of zircon sand

Naturally occurring zircon sand was plasma spray coated on steel substrates previously coated with NiCrAlY bond coat. The coatings were characterized for their microstructure, chemical composition, thermal shock resistance, and the nature of structural phases present. The as-sprayed coatings consisted of t-ZrO₂ (major phase), m-ZrO₂, ZrSiO₄ (minor phases), and amorphous SiO₂. These coatings, when annealed at 1200 °C/1.44 × 10⁴s yielded a ZrSiO₄ phase as a result of the reaction between ZrO₂ and SiO₂. Dramatic changes occurred in the characteristics of the coatings when a mixture of zircon sand and Y₂O₃ was plasma spray coated and annealed at 1400 °C/1.44 × 10⁴s. The t-ZrO₂ phase was completely stabilized, and these coatings were found to have considerable potential for thermal barrier applications.