齐齐哈尔碾子山麦饭石物化性能及其对Pb2+、Cd2+、Cr3+的吸附行为研究

以齐齐哈尔碾子山麦饭石为研究对象,通过比表面积及孔隙分析、阳离子交换容量(CEC)测试以及p H值缓冲能力测试等,对碾子山区麦饭石的结构和性能进行表征,并进一步研究麦饭石对Pb~(2+)、Cd~(2+)、Cr~(3+)的吸附行为。结果显示:碾子山区麦饭石具有海绵体大孔结构,阳离子交换容量(CEC)13~20 mmol/100 g。碾子山麦饭石对酸碱溶液都具有较好的调节能力,尤其对酸液的调节更高效。重金属吸附性能方面,对Pb~(2+)、Cd~(2+)、Cr~(3+)这3种离子吸附关系为:Pb~(2+)Cr~(3+)Cd~(2+)。     

关于提高金刚石钻头胎体耐磨性的试验研究

胎体耐磨性（胎体硬度）是金刚石钻头的一个重要技术指标,它直接影响钻头、钻进规程参数的选择和钻探工程技术指标的提高。目前,现场所用钻头实际胎体硬度低于出厂钻头的标称硬度,而钻探施工一般按胎体标称硬度进行安排生产,所以会对钻探效率和进尺的提高带来误导和负面影响。为了提高钻头胎体硬度,进行了如下研究工作：改进钻头烧结工艺,提高胎体材料中碳化钨的比例和增加混料时间。在改进钻头烧结工艺中,建议讨论研究俄罗斯冷压烧结技术,其烧结压力可以达到70～100 MPa,远远高于我国热压烧结的压力,这将有利于胎体耐磨性的提高和钻探技术经济指标的改善。     

A comparative assessment of sand and lime stabilization of residual micaceous compressible soils for road construction

Summary The presence of mica in pavements can be detrimental due to the effects of high compressibility and low compacted density it imparts to the soils. Three residual micaceous compressible soils derived from granite, granitic gneiss and phyllite can neither be used as base nor sub-base course in their untreated form. In this study, these soils have been treated with a range of lime and sand contents to determine their effects on consistency, compactability, bearing and compressive strengths and volume stability against swell. With 6–8% lime, soils derived over phyllite and granitic gneiss were rendered suitable for use as sub-base course as their plasticity index, 96 hour soaked CBR values and unconfined compressive strengths (UCS) were improved to satisfy existing local criteria. Similarly, with 30% sand both soils became suitable for sub-base course construction. The use of both additives markedly improved the volume stability of all the soils against swell.     

Une Microflore du Barrémien dans la Province de Valencia,Espagne

A Barremian microflora is recorded in the terrigenous facies (Weald) of the Lower Cretaceous in the northern region of the Province of Valencia (Spain), these beds have been poorly dated up to now due to the absence of fossils. The Villar del Arzobispo microflora correspond unquestionably to the Barremian-Aptien period, but the numerical importance of derived forms from the Jurassic, the remarkable variety of forms of Cicatricosisporites, and the rareness of pollen of Angiosperms, indicate a Barremian age to be more likely.This discovery permits us to establish the stratigraphical relationship of this terrigenousfacies of Villar del Arzobispo with the dated “Weald” of other areas of the Iberian Chain and to give a complete chrono-stratigraphical interpretation to the different litho-stratigraphical units that constitute the Lower Cretaceous of this region.     

Characterization and use of tropical gravels for pavement construction in West Africa

Summary Road transportation is increasingly becoming one of the key factors for promoting economic growth in most developing countries. However, transport and road research in the tropics has received relatively little attention. Experiences in road construction in the tropics within the past 50 years or so have established that local materials specifications and pavement construction technologies have to be developed in relation to the climatic conditions. This would involve knowledge of the processes of formation as well as genetic characteristics of the local gravels. Genetic characteristics exert considerable influence on the geotechnical properties and engineering behaviour of local gravels under pavement. The construction technology of the road pavement should take cognizance of the compositional variabilities of the gravel deposits. Construction studies of pavement sections (as well as assessment of the performance of existing roads) built with different gravels formed over different geological formations in specific climatic, and drainage conditions would provide useful data for evolving local gravel specifications for constructing stable and durable pavements. Stage construction of pavements involving the exposure of the various layers to traffic loading and seasonal climatic influences appears to hold promise for formulating strategies for constructing stable, and long-term durable tropical roads. The problem of achieving reproducible laboratory test data under field conditions is perhaps the most challenging aspect of utilizing local gravels for pavement construction in tropical and sub-tropical conditions. It is noted that the stability of pavements in tropical environments depends not so much on the geotechnical properties of the available gravels as on the appreciation by the designers and construction engineers of the relationship between the genetic and laboratory determined characteristics of the gravels on the one hand and the pavement construction technology and local climatic and drainage conditions on the other. This paper is a contribution to development of highway geotechnics for tropical and sub-tropical conditions.     

Predicting the overall properties of composite materials with small-scale inclusions or cracks

This paper will summarise the present state of knowledge concerning the elastic and dissipative properties of composite materials in the long wavelength or static approximation. In this case the material, although containing numerous inclusions or cracks or other types of microstructure, can be regarded as a continuum. Established results are listed for the elastic parameters following a review of approximate and exact methods of their derivation.     

颗粒材料的剪胀模型

本文研究了颗粒材料的剪切变形机制,建立了颗粒体在变形过程中应力与组构量的相互关系,论证了产生剪胀的微观组构条件,推导出各向异性组构颗粒体剪胀方程。做了相应的单剪试验,理论结果与试验结果相当吻合,从而验证了理论模型的正确性。     

Zinc Isotopic Compositions of NIST SRM 683 and Whole‐Rock Reference Materials

In this study the homogeneity of the zinc isotopic composition in the NIST SRM 683 reference material was examined by measuring the Zn isotopic signature in microdrilled sample powders from two metal nuggets. Zinc was purified using AG MP‐1M resin and then measured by MC‐ICP‐MS. Instrumental mass bias was corrected using the “sample‐standard bracketing” method and empirical external normalisation with Cu doping. After evaluating the potential effects of varying acid mass fractions and different matrices, high‐precision Zn isotope data were obtained with an intermediate measurement precision better than ± 0.05‰ (δ⁶⁶Zn, 2s) over a period of 5 months. The δ⁶⁶Zn_JMC‐Lyon mean values of eighty‐four and fourteen drilled powders from two nuggets were 0.11 ± 0.02‰ and 0.12 ± 0.02‰, respectively, indicating that NIST SRM 683 is a good isotopic reference material with homogeneous Zn isotopes. The Zn isotopic compositions of seventeen rock reference materials were also determined, and their δ⁶⁶Zn values were in agreement with most previously published data within 2s. The δ⁶⁶Zn values of most of the rock reference materials analysed were in the range 0.22–0.36‰, except for GSP‐2 (1.07 ± 0.06‰, n = 12), NOD‐A‐1 (0.96 ± 0.03‰, n = 6) and NOD‐P‐1 (0.78 ± 0.03‰, n = 6). These comprehensive data should serve as reference values for quality assurance and interlaboratory calibration exercises.     

Forty‐Nine Major and Trace Element Concentrations Measured in Soil Reference Materials NIST SRM 2586, 2587, 2709a, 2710a and 2711a Using ICP‐MS and Wavelength Dispersive‐XRF

Excellent agreement was noted in the concentration of major and trace elements in five NIST (National Institute for Science and Technology) soil reference materials (NIST SRM 2586, 2587, 2709a, 2710a and 2711a) between measurement results from wavelength dispersive‐XRF and ICP‐MS from two independent laboratories, and NIST certificate of analysis and literature data. We describe the variability in concentrations of up to forty‐nine elements (plus loss on ignition) and provide values for up to twenty‐one elements previously uncharacterised by NIST in these soil RMs. The additional characterisation provided in this investigation can be utilised to reduce the measurement bias of custom calibration routines and improve the quality of control checks developed using these NIST RMs.     

山东半岛海岸带北段地下水土腐蚀性评价

地下水、土对建筑材料的腐蚀性使建筑物缩短使用年限,并产生较大的安全隐患,该文通过对山东半岛蓝色经济区海岸带北段地下水、土的调查,结合取样分析测试结果,分析了海岸带北段地下水、土的化学特性,评价了其对工程建设中混凝土等建筑材料的腐蚀性,并提出了防治措施和保护建议。