乙二胺四乙酸二钠盐溶解后用ICP—AES法测定不纯重晶石和菱锶矿...

本文提出一种测定与脉石矿物伴生的重晶和菱锶矿中的钡，锶，硅及九种少量和微量元素的新方法，本法涉及在氢氧化铵存在埋，在乙二胺四乙酸二钠盐浓溶液的回流下，对试样进行煮沸溶解。在这种条件下，重晶石和菱锶矿定量溶解，任何伴生的硅酸盐和硫化物矿物杂质不能疲解，滤出后，在白金坩埚中灼烧至恒重。加入浓硫酸和氢氟酸后，对残渣加热，然后再灼烧至氧化物，以重量法测定二氧化硅。以硫酸氢熔融残渣。加入浓硫酸和氢氟酸后，对     

微波溶样火焰AAS法及火焰光度法测定茶叶中的钙镁铁锰铜锌钾钠

本文采用改装家用微波炉及自制聚四氟乙烯消化罐,用HNO_3-H_2O_2密闭增压消解样品,用火焰AAS测定Ca、Mg、Fe、Mn、Cu、Zn,用火焰光度法测定K、Na。本法简便、省时,溶样耗能低,对环境污染小。 测定茶叶中的微量元素,首先要考虑的是样品溶液的制备。目前大多数采用干法灰化或湿法消解试样。干法易引起易挥发元素的损失,所得灰分易结成硬块粘附在坩埚底,有时无机盐将炭粒包藏,使灰化不完全;湿法消解样品时,容易引起样品沾污或痕量元素的损失,且不易消解完全。     

热解石墨坩埚的应用

本文介绍本院研制的热解石墨坩埚的特性和应用情况。该坩埚具有纯度高、致密、耐高温、耐强酸强碱腐蚀、易洗涤等特点,已广泛应用于矿物、建材、玻璃等方面试样的前处理。与铂、银、镍、刚玉、石英等坩埚比较,具有引入杂质少成本低等优点。     

恒载作用下损伤梁的弯矩重分布研究

根据等效刚度原理定义损伤程度,对损伤采用损伤位置、损伤程度和损伤长度三个参数来描述,从材料力学平面弯曲理论出发,运用小变形的平面弯曲挠曲线近似微分方程,并引入损伤程度的定义,推导出恒载作用下两端固定损伤梁弯矩方程的隐含表达式。对恒载作用下两端固定损伤梁进行了各种损伤情况下弯矩重分布的对比分析,总结出了其弯矩重分布规律。本研究的目的是期望为桥梁的健康检测、损伤识别理论研究奠定基础。     

低温环境下铁同位素分馏的若干重要过程

详细了解同位素分馏的过程与机理是运用稳定同位素体系解决科学问题的关键.本文对沉淀、溶解、吸附、氧化、还原、生物等过程中的Fe同位素分馏研究结果进行了系统总结.在沉淀过程中,优先沉淀轻同位素;在吸附过程中,Fe(Ⅲ)矿物优先吸附重同位素;氧化还原过程中,Fe的化合价越高,Fe同位素组成越重.     

微波炉法测定遗址土含水率的可靠性研究

古代土遗址病害发展与土的含水率变化密切相关,但土遗址保护现场快速准确测定土的含水率不是一件容易的事。选择遗址土、含盐土、黄土等进行对比试验,研究分析微波炉烘干法（简称微波炉法）测遗址土含水率结果的可靠性。在测定试验土样界限含水率和易溶盐含量的基础上,对比分析微波炉法、烘箱法两种方法测定土含水率的误差来源。试验结果表明,土的塑性对微波炉法的测定有一定影响,但测定误差均在2%以内;土的含盐量影响水分的蒸发速度,不影响微波炉法的测定结果;微波法测定遗址土含水率准确,且具有快速、便捷等优势,值得在土遗址保护工程中推广使用。     

金属矿物微化反应特征在重砂鉴定中的指示作用

重砂鉴定是矿物鉴定的重要方法之一。由于在风化、搬运、样品加工等过程中一些重砂矿物物理性质不稳定,用于矿物鉴定的特定物理特征常常不明显,造成重砂矿物鉴别困难。特定微化学反应为鉴别这类矿物提供了快速、简便、准确手段。笔者根据多年来对黔东南地区重砂样品的鉴定工作实践,并参考前人的研究资料,讨论了铜、铅、锌金属矿物微化反应特征在重砂鉴定中的指示作用:黄绿色叶片状的硫氰酸汞铜结晶指示了待测矿物中铜元素的存在;柠檬黄色六边形片状的碘化铅晶体沉淀指示了待测矿物中铅元素的存在;毛十字状、雪花状及羽毛状硫氰酸汞锌复盐沉淀指示了待测矿物中锌元素的存在。     

等离子质谱法测量土壤中铅、镉、铬的消解方法比对

通过高压罐密闭消解、微波消解与聚四氟乙烯坩埚常压消解,等离子质谱法测量土壤中重金属铅、镉、铬,结果表明三种方法均满足土壤质量评价要求,其中聚四氟乙烯坩埚常压消解除铬元素系统稍偏低。聚四氟乙烯坩埚常压消解具有简单,快速,稳定,方法线性范围为(0~200)ng/m L,相关系数均在0.999以上,铅、镉、铬检出限分别是0.7,0.03,3 ng/m L,能满足农业土壤重金属测量要求。     

碳酸钠碱熔-电感耦合等离子体发射光谱法测定石墨中的常量元素硅铝钙镁铁钛锰磷

石墨化学性质稳定,需采用高温碱熔(1000℃)才可使样品分解完全,已有分析方法在样品前处理不同的阶段使用不同材质的坩埚。基于石墨性质和坩埚熔样情况,本文采用预先已均匀铺垫0.50 g碳酸钾的高熔点铂坩埚灼烧石墨样品,样品灼烧后直接在原坩埚中加入0.80 g碳酸钠碱熔,熔融物用稀盐酸提取后用电感耦合等离子光谱法(ICP-OES)实现了石墨中8种常量元素(硅铝钙镁铁钛锰磷)的同时测定。方法检出限为13~228μg/g,方法精密度(RSD,n=12)为0.7%~7.2%;全流程加标回收率为90.5%~105.0%;实际土状和鳞片石墨样品的测定结果与化学分析法无显著差异。本方法避免了铂坩埚的损毁和样品在前处理过程中的损失,分析过程简单、分析速度快。     

旋喷止水帷幕在北京恒润中心工程中的应用

介绍了止水帷幕在北京恒润中心工程基坑开挖中的应用，对止水帷幕的设计以及三重管高压旋喷桩的施工工艺进行了论述。     

Phycoremediation of cyanide from coke–oven wastewater using cyanobacterial consortium

Owing to the presence of several toxic pollutants such as cyanide, phenol, ammonium, coke–oven wastewater is being considered as hazardous stream and needs to be treated properly. In the present study, cyanobacterial consortium of Dinophysis acuminata and Dinophysis caudata, collected from East Kolkata Wetland, was used for the treatment of both synthetic cyanide solution and real coke–oven wastewater. The growth kinetics was studied considering nitrate as substrate. Since consortium showed growth in cyanide solution, a model was proposed considering both nitrate and cyanide as substrates. The simulated data match quite well with experimental ones. Two coke–oven wastewater samples were collected—untreated one from equalization tank and another from secondary clarifier effluent and treated with consortium separately. Lipid was extracted from biomass of native cyanobacterial consortium, biomass treated with raw coke–oven wastewater and biomass treated with secondary clarifier effluents. Fatty acid methyl ester of such lipid samples was analyzed using gas chromatograph.     

Spectroscopic and macroscopic studies of the adsorption of arsenate and phosphate on polynuclear aluminum organomineral precipitates

Aluminum organic coprecipitates play important roles in the transport of oxyanions in soil environment.A new polynuclear aluminum organomineral precipitate(Al13-oxalate precipitate) was prepared to investigate the adsorption behavior of arsenate and phosphate on noncrystalline aluminum precipitates.Important thermodynamic parameters for adsorption reaction were evaluated using macroscopic adsorption data and equations.The result showed that,the adsorption reaction basically is a diffusion process.FTIR spectroscopic studies have provided evidence for the formation of two different types of complexes in substrate,protonated bidentate and deprotonated bidentate complexes at pH 4 and pH≥6,respectively.The classic competitive adsorption and XPS studies both indicated that phosphate has stronger chemical interaction with substrate than arsenate.The findings of XPS studies revealed that the precipitate substrate can act as Lewis acid when adsorbing oxyanions.     

适用于检测冻土的超声波测试系统的设计与研制

超声波波速测试作为一种无损检测已经广泛应用到岩土工程行业,该测试方法也是获得岩土体物理力学参数的有效方法.目前鲜有关于冻土的声波测试的技术和方法的报导,已有的冻土声波测试都是在垂直方向上忽略换能器的质量并在常温下快速测试声波通过时间,难以满足测试精度.鉴此,在购置常温声波测试主机的基础上,充分考虑冻土对温度敏感的特性、换能器在水平方向的测试以及土样与换能器之间的耦合程度,设计了一种适用于多种类型的冻土超声波换能器支架和恒温箱的测试系统,恒温箱意在提供适合不同温度下土体的测试环境（-30℃～+30℃）,换能器支架可供低温、提供多种尺寸冻土试样的横波和纵波的测试平台.为避免垂直测试中换能器和土样自身对测试的影响,除了支架提供水平测试平台外,在调节换能器与土样接触距离的螺杆顶端放置应变片测试冻土样与换能器之间的接触程度以提高冻土声波波速的测试精度.利用该测试系统对不同负温下冻土样品进行测试,数据结果证明了该测试系统的实用性和良好的测试精度.     

Examination of the jarosite–alunite precipitate addition in the raw meal for the production of Portland and sulfoaluminate-based cement clinkers

The aim of the present research work was to investigate the possibility of adding a jarosite–alunite chemical precipitate, a waste product of a new hydrometallurgical process developed to treat economically low grade nickel oxides ores, in the raw meal for the production of Portland cement clinker. The precipitate was also tested in the production of non-expansive, sulfoaluminate-based cement clinker, as a substitute for gypsum because of its high sulfate content. For the Portland clinker, two samples of raw meals prepared, one with ordinary raw materials (reference sample) and another with 1% jarosite–alunite precipitate. Both raw meals were sintered at 1450 °C. For the sulfoaluminate-based clinker, one raw meal contained 20% gypsum (reference sample) whereas the other contained 11% of the precipitate. Both raw meals were sintered at 1300 °C. The results of chemical and mineralogical analyses as well as the microscopic examination showed that the use of the jarosite–alunite precipitate did not affect the mineralogical characteristics of the so produced Portland cement clinker. In the case of sulfoaluminate-based cement clinker, there was confirmed the formation of the sulfoaluminate phase (C₄A₃S¯), the most typical phase of this cement type.     

浅谈东胜南部煤矿区铁合金专用焦炭生产工业的发展

东胜矿区煤炭资源丰富 ,其优越的煤炭特性 ,是生产铁合金专用焦的理想原料。采用简易机焦炉生产铁合金专用焦是较为理想可行的工艺。     

石油污染多孔介质含水量测定技术

石油污染多孔介质中含有石油和水分,采用传统的烘干法测定其含水量时,水分和油分会同时产生挥发,无法准确测定含水量。在传统烘干法测定含水量的基础上,根据水分和油分不同的挥发特征,提出了石油污染多孔介质含水量的定义和计算公式,测定了不同石油在多孔介质中的烘干损失系数,建立一种测定石油污染多孔介质含水量的改进烘干法。结果表明:该法测定的石油污染多孔介质的含水量与实际值的误差约为0.10%~0.50%,低于传统方法的测定结果,可用于室内各项石油污染多孔介质的模拟研究。     

Preparation of iron phosphate from sludge sourced from the electrocoagulation treatment of source-separated urine

In order to prepare iron phosphate by waste sludge, we report a method for effective utilization of the sludge obtained from the electrocoagulation treatment of source-separated urine. The sludge was dissolved with hydrochloric acid and pretreated with H₂O₂ and Na₃PO₄; finally, NaOH was added to precipitate iron phosphate from the solution. Thermal treatment of the precipitate at 750 °C in air yielded crystalline quartz-like anhydrous FePO₄. The precipitate was characterized by a number of thermal techniques such as thermogravimetry/differential thermal analysis, scanning electron microscopy, and X-ray powder diffraction.     

Iron oxide precipitate in seepage of groundwater from a landslide slip zone

Orange precipitate was collected at the mouth of groundwater drainage tubes from the Kumanashi Landslide slip zone in Toyama prefecture, Northwest Japan. Data from XRF, X-ray diffraction, and Mössbauer spectroscopy determined the precipitate as hydrous ferric oxide (HFO) bearing multi-elements such as phosphorous, silica, calcium, etc. The occurrence of HFO may indicate an oxidation of ferrous iron in the percolated groundwater from the slip zone. Moreover, the precipitate iron should be mobilized with groundwater circulation from the slip zone, whose reducing condition was determined by the iron speciation on the same type of landslide profiles within the study area in previous studies. The HFO precipitate may be considered as a secondary reliable indicator to locate the seepage of a slip zone on surface, especially for a landslide newly investigated under wet-warm climate.     

Rate control in feldspar dissolution—II. The protective effect of precipitates

The ability of precipitates formed during incongruent dissolution of feldspars in aqueous solutions to act as barriers to mass transfer between the feldspar and the bulk solution is examined using the available textural evidence on such precipitates.

The propensity of precipitates for forming compact coatings on the dissolving grains is measured by a characteristic distance of diffusion of the precipitating component, a function of the diffusion coefficient of the component in solution and of the rate constant for its precipitation. The available evidence on precipitates formed during dissolution of feldspars, complemented by the evidence on similar precipitates produced from comparable solutions in the absence of feldspars, is sufficient for evaluating the protective effect of precipitates under laboratory conditions, and for setting limits to the conditions under which such an effect could be important during weathering and diagenesis.

Feldspar dissolution in the reported kinetic experiments at room temperature and 3 pH 10 could not have been controlled by diffusion through the precipitate, and changes in the rate of release of alkalies after the first couple of days in Lagache's experiments at 200°C also could not have been controlled by diffusion through the precipitate. Other things being equal, characteristic distances of diffusion of components reprecipitated during incongruent dissolution of silicates decrease with increasing temperature, and coating of dissolving grains by compact precipitate layers should be more common at metamorphic temperatures than in the temperature range of weathering and diagenesis.     

焦炉烟气中复杂有机污染物采样技术研究

报道了自行设计的收集、吸附、吸收多级串联采样装置，成功地用于一次采集焦炉烟气中以三种形态存在的有机污染物。经ＧＣ／ＭＳ检测出２９３神有机污染物，其中７１种为重点污染物。此项技术能够全面真实地反映焦炉烟气中全量多环芳烃和其它复杂有机污染物的状况。