辽宁沿海经济带水资源边际效益测度及影响因素分析

水资源边际效益的研究对于辽宁沿海经济带可持续发展具有重要意义.基于边际效益的理论,将水资源作为生产要素,利用柯布-道格拉斯生产函数对辽宁沿海经济带2002—2011年的水资源利用边际效益进行了测算及时空差异分析,结果显示三次产业水资源利用边际效益逐年提高,农业、工业、第三产业用水边际效益多年平均值分别为4.11、82.30、154.93 元/m³,农业用水的边际效益明显低于工业和第三产业用水.在此基础上构建多元线性回归模型,探求水资源利用边际效益的关键性影响因素,得到农业用水边际效益影响因素:农业万元产值用水量、政府影响力、单位面积产量、化肥使用量,其中农业万元产值用水量对于农业用水边际效益的影响程度最强且为负向作用;工业用水边际效益影响因素:工业万元产值用水量、政府影响力、市场需求程度、工业废水排放达标量,且工业万元产值用水量对于工业用水边际效益的影响最大且为负向作用;第三产业用水边际效益影响因素:第三产业万元产值用水量、政府影响力、城市化水平、人均公园绿地面积,第三产业万元产值用水量和人均公园绿地面积对于第三产业用水边际效益影响程度较高,第三产业万元产值用水量为负向作用,人均公园绿地面积作用为正向作用.     

浅部地下洞穴散射瑞利波对表观相速度影响

均匀半无限体中表面源激发的瑞利波能量在介质浅部占主导地位。当前行瑞利波遇浅部洞穴时,瑞利波在洞穴发生散射。以洞穴作参照位置,波场沿前行波方向可依次分为前方、上方、后方三个区域。前方远场散射波以反射瑞利波为主,传播特性与入射波相同;当洞穴几何参数满足一定条件,上方散射波可形成与兰姆波传播特性类似的导波;后方远场由透射瑞利波主导。受散射波影响,表面波场表观相速度出现扰动,不同位置扰动特征不同,若测线下方有浅部洞穴存在,由不同位置相速度扰动特征差异,可预测洞穴方位,由前方相速度特征扰动对应波长可预测洞穴埋深。     

Removal of copper from aqueous solution by Ascophyllum nodosum immobilised in hydrophilic polyurethane foam

The seaweed Ascophyllum nodosum was pre-treated by successive washes in distilled water and dilute acid, dried, and pulverised to produce particles of <150 microm. These were immobilised during the manufacturing process of Hypol 2002 polymer to form a biomass/polymer matrix that was stable and easy to handle. In making the composite a mixing speed of 360 rpm for 20-30 s with 2% (w/w) addition of surfactant to pre-polymer was found to be ideal. The average pore sizes for different water polymer mixes (expressed as volume ratios) were 1.66 mm +/- 0.98 (ratio 0.75:1), 1.58 mm +/- 0.76 (ratio 1:1), 1.64 mm +/- 0.6 (ratio 1.5:1) and 1.11 mm +/- 0.615 (ratio 2:1). The biomass/polymer was used alongside free native biomass in an initial adsorption experiment using a 0.0315 mmol dm(-3) Cu (II) solution and gave a copper uptake capacity [Formula: see text] of 0.037 mmol Cu g(-1) dry weight seaweed in both cases which represented approximately 85% of total initially available copper. In later adsorption isotherm experiments using Cu concentrations between 0.0315 and 0.944 mmol dm(-3) at pH 5.0 and immobilized biomass over five consecutive adsorption/desorption cycles the biomass/polymer showed an initial lowering of adsorption capacity but stabilised at 0.23 mmol g(-1) dry weight by the third re-use. The q(max) of the immobilised biomass decreased from 0.55 and 0.416 mmol of Cu g(-1) dry weight when pH was lowered from 4.0 to 3.0, and increased from 0.576 mmol g(-1) dry weight (biomass) at 283 K to 0.636 mmol g(-1)(biomass) at 303 K.     

Natural resource availability: Some economic aspects

This paper treats some of the more important aspects of natural resource availability. This includes a definition of real or opportunity costs in resource extraction as compared to money costs; some economics of secondary materials and recycling; energy resources; and a demonstration of the effect of exponential growth in resource use on the time to resource exhaustion. The paper concludes with a short note on econometrics and commodity models.     

Landowner equity in Papua New Guinea's minerals sector: Review and policy issues

The involvement of local communities as equity holders in major mineral resource developments dates back over a decade in Papua New Guinea. This article reviews the history and result of landowner equity at two of Papua New Guinea's major mines (Porgera and Lihir), with a particular focus on the contribution of these equity holdings to local sustainable development. It is found that while an equity holding can provide significant returns to a local community, it also exposes them to significant financial risk. A second major area of concern is the structures and instruments by which revenues generated from the equity are distributed and utilized within the local community. Further research and policy redirection is required before local equity holding can be viewed as making a significant contribution to local sustainable development.     

羧基丁苯聚合物混凝土小变形阻尼研究

材料的阻尼是衡量材料本身成振性能的主要指标。本文采用自由振动法测试得到了一批羧基丁苯混凝土小变形阻尼比的基础性数据。试验结果表明:所采用的阻尼比测试方法和试验过程是可靠的;对同类型的混凝土,混凝土的阻尼比随丁苯胶掺量的增加而增大,混凝土的弹性模量随丁苯胶掺量的增加而降低;丁苯胶掺量在10％～15％时,可获得阻尼比、弹性模量和抗压强度均较高的混凝土。     

机组行为、时间余量与飞行安全间的关系探讨

探讨机组行为、时间余量与飞行安全间的关系，为航空公司的机组训练和避免飞行事故及飞行事故征候的发生提供帮助。利用1996—2000年中国民用航空总局航空安全办公室下发的“飞行事故、航空地面事故和飞行事故征候统计的通知”中的资料，找出因机组行为错误导致的、与解决问题的时间余量关系密切的飞行事故和飞行事故征候案例。与飞行专家进行研讨和分析，探求飞行事故及其征候的发生与机组行为和时间余量间的关系。找出了因机组行为错误导致的、与解决问题的时间余量关系密切的飞行事故11起和飞行事故征候133起。其中因机组疏于监控飞机设备和状况、未发现问题存在或未明确所发生的问题的性质而无作为，使得解决问题的时间余量为零或接近零，从而无时间解决出现的问题，导致飞行事故3起和飞行事故征候96起；因机组发现问题存在并在明确所发生的问题的性质后，在一定时间余量内未能突破思维惯性的影响，做出了错误的决策，未能解决所发现的问题，导致飞行事故8起和飞行事故征候37起。飞行事故和飞行事故征候的发生与机组行为和时间余量的关系是，机组行为可以决定时间余量剩余的多少，时间余量的多少反过来决定机组采取何种措施解决当前的问题才能避免飞行事故和飞行事故征候的发生。     

印染废水处理工艺研究

采用“混凝-水解酸化-二级生物接触氧化一砂滤”工艺处理印染废水，具有处理效果好、运行稳定、投资省等优点，出水水质达到《纺织染整工业水污染排放标准》（GB4287—92）中的一级标准，且处理水可以完全回用。