在综合力场中回收砂金的新设备

本文从砂金选矿设备进展入手,介绍了圆形跳汰机、离心淘汰盘、振筛差动溜槽及鼓动溜槽的分选特点和应用情况,并指出了这些设备的局限性,同时提出了应用综合力场—即重力、离心力、剪切力、向心推力及摩擦力等的联合作用才是分选砂金的最佳方法。本文着重介绍新型曲面旋流选金器应用综合力场的设计结构特点及选别指标。     

Search images: Selective attention to specific visual features of prey.

In 3 experiments, pigeons (Columba livia) searched a digitized image of a gravel patch on a computer monitor for cryptic grains. Experiment 1 demonstrated that the bird's ability to detect a type of grain improved over successive encounters, and detection of alternative targets was attenuated when a search image was active. Experiment 2 demonstrated search-image effects independently for the 2 grains. Perception was biased to detect wheat grains after wheat encounters and was biased to detect bean grains after bean encounters. Experiment 3 demonstrated that when a search image was activated, selective attention was heightened to the visual features of the grain used to discriminate it from the multicolor gravel background. These results provide strong support for the view that search images are selective attention to specific visual features of cryptic prey. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Discharge Characteristics of Skew Sluice Gates

Discharge characteristics for a skew sluice gate, ranging between the two extreme cases of a side sluice gate and a normal sluice gate, have been explored. The concept of an elementary discharge coefficient was utilized for obtaining the discharge through a skew sluice gate. Based on experimental investigation, equations for elementary discharge coefficients for skew sluice gates in free- and submerged-flow conditions were obtained. These equations describe the behavior of the elementary discharge coefficients for large ranges of the upstream water depth to gate opening ratio, tailwater depth to gate opening ratio, and skew angle. Using these equations, it is possible to obtain the discharge passing through a bifold skew sluice gate and it is expected that these equations will be useful to obtain the discharge through sluice gates having any plan shape.     

湖北嘉鱼蛇屋山金矿氧化带地质特征研究

通过对蛇屋山金矿钻孔资料及浅井资料的深入研究，将松散层自上而下划分为硅帽、褐红色砾粘土、浅色网纹状粘土、棕灰－棕红色粘土、弱风化带等五个层位。金主要赋存于棕灰－棕红色粘土层以及浅色网纹状粘土层的下部。金矿的形成受制于基岩的含金性及第四纪的风化作用，属红土型金矿床。     

反铲—漂浮式砂金洗选厂的开发与应用

反铲—漂浮式砂金洗选厂是长春黄金研究所最新开发的一种砂金采选设备。该设备是应用了我所已研制成功的洗选设备;通用的液压挖掘机;组装式平底船;鼓动溜槽;最新式四面射流喷射泵以及独特新颖的连接装置而设计的。洗选厂安装容易,便于搬迁,既节省了矿砂的运输费用,又降低了采选作业成本。此外,新式的排尾方式,也获得了令人满意的复田效果。     

山东牟平阎家疃金矿床地质特征及成因探讨

阎家疃金矿床位于胶东三大金成矿带中的牟平—乳山金成矿带,是鹊山岩体中受小规模SN、NNE向断裂控制的破碎带蚀变岩型和硫化物石英脉型复合型金矿床。通过矿相学和电子探针分析,对阎家疃金矿床矿石金属矿物特征和金矿物赋存状态进行研究,确定了金属矿物的共生组合及其生成顺序。发现金矿物大部分为粒径＜0.074 mm的中细粒金,赋存状态以粒间金为主,包裹金次之。金矿物的成色高于牟平—乳山金成矿带内的其他金矿床,且富含Bi,认为阎家疃金矿床成矿深度为中深部。在总结区域成矿地质背景和矿床地质特征的基础上,通过类比区内金矿床成矿年龄来探讨矿床成因,初步认为早白垩世胶东地区岩石圈大规模拆沉、壳幔强烈相互作用,俯冲板片变质脱水形成大量成矿流体,活化前寒武纪变质基底岩石中的金等成矿物质,含金流体沿金牛山断裂运移,在NNE和SN向断裂交会处,破碎程度高、孔隙度大的位置沉淀成矿。     

贵州泥堡卡林型金矿断控型矿体的地层和岩性条件研究

贵州泥堡卡林型金矿是黔西南碳酸盐岩台地相区首次发现的大型断控型矿床,其主要控制因素除断层之外,地层和岩性也是不可忽视的重要因素。岩石学研究表明：断控型矿体的主要赋矿围岩是含钙质（沉）火山角砾凝灰岩,而不是前人认为的砾屑砂岩;具有块状构造的（沉）火山角砾凝灰岩在构造作用下裂隙发育,岩石孔隙度明显增高,热液作用下易形成厚度大且品位高的断控型金矿体。同时,根据含矿岩石主要含火山成分的特点,认为这套地层应该划归为二叠系峨眉山玄武岩组,而不是前人划分的龙潭组。含钙质（沉）火山角砾凝灰岩和二叠系峨眉山玄武岩组分别是形成断控型矿体的重要岩性和地层条件。提出在碳酸盐岩相区寻找类似泥堡金矿的断控型矿体时,除了考虑断层外,还要考虑是否有合适的地层和有利的赋矿岩性。     

金厂峪金矿碎石尾砂浇注胶结充填技术的应用

通过室内试验测定了尾砂的特性以及充填体强度随料浆浓度和灰砂比的变化规律,结合金厂峪金矿现场实际需求确定了充填灰砂比,根据现场地形及生产需要设计了皮带输送两段搅拌造浆充填系统,并分别从充填工艺及充填系统建设两方面介绍了碎石尾砂浇注胶结充填技术在桑家峪矿区的应用。可为类似条件空区处理提供借鉴。