20世纪末矿物学的任务

对过去十年中苏联矿物学领域取得的成就作了肯定,指出了苏联矿物学发展中某些不足之处和急待加强或改进之处。为了加速苏联国民经济各部门的科技发展,提出了下列几方面的矿物学任务:研究方法的任务,矿物种类和变种的研究任务,发展成因矿物学的任务、标型矿物学任务和有关矿物学概念和术语的几点意见。     

菲律宾吕宋岛三描礼士蛇绿岩中的耐火型和冶金型铬铁矿石

<正> 序言豆荚状蛇绿岩型铬铁矿床是高级冶金型铬铁矿石(Cr_2O_3 45—60wt%)的重要来源,并且是耐火型铬铁矿石(Al_2O_3最低为25wt%,Cr_2O_3+Al_2O_3最低为60wt%,FeO最高为15     

城市及其遗产:保存的根源和条件

城市遗产的保存和利用将都市管理的负责人置于艰难选择的境地.下面的文字对城市的构 成进行了简短的历史回顾，得出了在场所利用及其保存之间保持平衡发展条件.     

磷、磷块岩与前寒武纪-寒武纪交界时期生物骨骼的演化

<正> 前寒武纪-寒武纪交界时期发生的从软体动物到介壳动物的变化,是地质记录中最引人注目、最重要而又了解最少的事件之一。关于这一事件(通常被称为寒武纪生物激增或寒武纪辐射(radiation)事件)的起因,一直是众多推测的对象。可能的解释包括:大气氧含量达到临界水平或大气中二氧化碳浓度降低;由于世界范围的海侵形成了新的浅海生态环境;由     

A comparative study on emergent pollutants photo-assisted degradation using ruthenium modified titanate nanotubes and nanowires as catalysts

Several methods have been used to tailor nanomaterials structure and properties.Sometimes,slight changes in the structure outcomes expressive improvements in the optical and photocatalytic properties of semiconductor nanoparticles.In this context,the influence of the metal doping and the morphology on a catalyst performance was studied in this work.Here,ruthenium doped titanate nanotubes(RuTNT) were synthesised for the first time using an amorphous Ru-containing precursor.Afterwards,the photocatalytic performance of this sample was compared to the one obtained for ruthenium titanate nanowires(RuTNW),recently reported.Two samples,RuTNW and RuTNT,were produced using the same Ru-containing precursor but distinct hydrothermal methodologies.The powders were structural,morphological and optical characterized by X-ray diffraction and fluorescence,transmission electron microscopy,Raman,X-ray photoelectron and photoluminescence spectroscopies.Distinct variations on the structural and optical properties of the RuTNT and RuTNW nanoparticles,due to ruthenium incorporation were observed.Their potential use as photocatalysts was evaluated on the hydroxyl radical photo-assisted production.Both samples were catalytic for this reaction,presenting better performances than the pristine counterparts,being RuTNT the best photocatalyst.Subsequently,the degradation of two emergent pollutants,caffeine and sulfamethazine,was studied.RuTNT demonstrated to be better photocatalyst than RuTNW for caffeine but identical performances were obtained for sulfamethazine.For both catalysts,the degradation mechanism of the pollutants was explored through the identification and quantification of the intermediate compounds produced and several differences were found.This indicates the importance of the structural and morphological aspects of a material on its catalytic performance.     

对美国金矿业基础的评价

<正> 引言1969年,美国对美元作了自动贬值。这一行动导致黄金价格在随后的4年里失去了控制,同时也使美国金矿业得到了复苏。本世纪70年代出现的极度通货膨胀导致了贵金属价格的急剧上涨。因此,人们对金矿的勘探和开采产生了日益增长的兴趣。少数幸存下来的采金者开始焕发了热情,他们都是在金价格长期固定不变而采金成本不断增加的情况下,靠勉强能维持收支平衡的利     

硫矿化在阿斯特拉罕气田硫化氢形成过程中的作用

<正> 阿斯特拉罕凝析气田以硫化氢的浓度高为特征。矿床中H_2S的成因问题,不仅具有理论意义,而且具有实际意义,因为不管是在黑海沿岸的盆地,还是在其它地区,预测高浓度硫化氢聚集的可靠性,在相当大的程度上取决于对H_2S成因的正确认识。关于矿床中硫化氢的成因有两种观点。第     

生态系统和工程

1.引言生态学是研究生物及其生活环境的科学,生物用反馈机理来调整它们的环境。无生命的环境及其中有生命的居住者统称为一个生态系统。一个生态系统小至一滴水,大至整个地球。其范围的限定以进入和排出量可被测知为准,但实际上     

厂内工艺调整减少污泥

本文主要通过简单的工艺调整来减少入海处置污泥的体积,以降低处置费用。采用的技术包括;消化污泥回流、笔析、淘洗——再浓缩,以及高温消化。这里既可使用单项技术,也可多项并用。这类抟术极大部分可通过现有的设备和花费极少的费用付之实施。     

Cultural Relevance for Rural Community Development in China: A Case Study in Bai, Jingpo and Huyaodai Communities of Yunnan Province

A three-year study over the Bai, Jingpo and Huayaodai communities in Yunnan Province reveals that the community development is significantly influenced in various ways by such cultural factors as the concepts of development; concepts and traditions of inter-community relationships, consumption, mar- riage and gender; patterns of decision-making and production, resource and income allocation; as well as the role of information dissemination systems, religion and ritual. Based on the analysis over the interactive relevance between each factor and community development, some strategies and methods for dealing with such a cultural relevance in development projects are recommended.