土壤中游离重金属离子的测定--唐南膜平衡法

对比了最近几十年来国内外土壤溶液中游离重金属离子浓度的测定方法,在此基础上建立了一种新的测量方法———唐南膜平衡法(DMT)。研究表明,该实验方法可以在不影响反应体系平衡的基础上同时测定多金属元素,而且彼此之间不会发生干扰。     

汽车内饰材料燃烧特性的评价方法及试验分析

燃烧行性是汽车内饰材料的重要特性指标之一,该文对目前我国有关汽车内饰材料燃烧特性评价方法的强制性国家标准以及欧洲法规规定的评价方法进行了全面的介绍和对比分析,文中还结合我国汽车内饰材料的评价试验结果评价试验方法所存在的问题进行了分析,提出了一些新的评价指标的建议。     

利用模糊集理论评价公路客运站安全管理工作

利用模糊集理论建立一种模糊综合评价方法来评价交通运输系统内部的公路客运站安全管理工作。分别通过评价语言变量和权重语言变量将评价指标体系的定性指标和定量指标及权重全部转化成三角形模糊数,克服定性与定量指标不具有可比性的缺点,使评价更客观、精确。基于最优度概念,将权重模糊评价矩阵转化成模糊单一评价矩阵,避免传统模糊数之间比较的复杂性和不精确性。考虑到评价者在模糊评价环境下对风险的态度,将乐观系数引入评价的过程。采用TOPSIS方法计算出评价方案的综合评价分数并进行排序。结合桂林市10个客运站安全管理工作评价实例,通过改变权重值对评价结果进行敏感性分析。方法概念清晰,计算过程直观与简单,评价结果公正与合理,不但可在交通系统内推广,同样也可适合于其他各领域模糊环境下的评价问题。     

钛管的一次压扁成形工艺

此文研究了钛管装入聚胺脂芯棒后一次压扁成形的工艺特点,分析了以往空心管成形所存在的问题。在实验的基础上完成了不同规格钛合金管材的一次压扁成形。     

产品设计模具制造及并行工程

为快速响应市场,实现并行工程方法是企业增强竞争力的一种策略和途径。文中概述了在产品设计和模具制造中，实现并行工程方法应创造的技术支持环境和管理基础。     

冷挤压双层组合凹模的最佳设计

此文应用厚壁圆筒弹性解,推导了冷挤压双层组合凹模,具有最大弹性极限时所能承受的最大挤压应力的计算公式,以及满足上述条件时双层组合凹模分界面半径和分界面过盈量的计算公式.利用上述各式,可使组合凹模获得最佳设计.     

顶头热挤压模具设计与制造

此文主要介绍了无缝钢管管坯穿孔用顶头在热挤压成形时,其热挤压模具的工作原理、主要特点,同时分析了该模具结构及其材料的选用对顶头加工质量的影响。     

Qualitative and Quantitative Assessment of Land-Use Managers' Attitudes Toward Environmental Justice

This study examines the outcome of efforts to educate federal land-use managers about their roles in implementing the Executive Order in their respective districts. The managers participated in a 6-h Nominal Group Technique (NGT) workshop where they were instructed to weight environmental justice issues versus others associated with hazardous waste problems in their districts. Participant responses were quantified and analyzed through a series of rounds. After each round, participants received increasing amounts of information on environmental justice issues. It was hypothesized that the managers would come to a consensus that environmental justice is an important issue that should be seriously addressed. Prior to administering the NGT, the managers appeared to have limited knowledge of environmental justice issues and thus assigned relatively low rankings to such concerns. After being “educated” by viewing films on environmental justice and reading related literature, in general, managers' weightings decreased and a narrower consensus developed. The authors conclude that exposure to the issue may not be as effective as expected in convincing land-use managers to become sensitive to justice issues so that they may effectively implement the Executive Order.     

Does trade openness improve environmental quality?

The literature on trade openness, economic development, and the environment is largely inconclusive about the environmental consequences of trade. This study treats trade and income as endogenous and estimates the overall impact of trade openness on environmental quality using the instrumental variables technique. We find that whether or not trade has a beneficial effect on the environment varies depending on the pollutant and the country. Trade is found to benefit the environment in OECD countries. It has detrimental effects, however, on sulfur dioxide (SO₂) and carbon dioxide (CO₂) emissions in non-OECD countries, although it does lower biochemical oxygen demand (BOD) emissions in these countries. We also find the impact is large in the long term, after the dynamic adjustment process, although it is small in the short term.     

综采工作面安全性评价的逼近理想解(TOPSIS)方法

基于熵权的TOPSIS(逼近理想解的排序方法)方法是一种新的安全性评价方法,该方法以灰熵理论确定评价指标的权重———熵权,从而避免低层次多因素权重确定的主观性。以评价对象与理想解和负理想解的距离确定的相对接近度作为评价准则,避免了评价方法的主观性。通过对平顶山煤业集团有限责任公司六矿综采工作面安全性进行的评价,指出综采工作面安全管理中存在的问题,并提出相应的改进措施。理论与实例表明,该方法较其他方法更加客观,更易于操作,结果也更符合生产实际。