药型罩参数对聚能射流水下运动的影响

目的 研究药型罩结构参数对所形成的聚能射流在水中运动的影响,改进水中聚能射流的运动特性。方法 采用多物质单元ALE法就锥形罩射流对水介质的侵彻进行数值模拟,分析锥形装药结构中药型罩锥角和厚度对所形成的聚能射流侵彻水时运动参数的影响。结果 锥形罩锥角大小及药型罩厚度对聚能射流在水中的形状、射流速度、加速度等有着明显的影响。侵彻体进入水中10 cm后,药型罩的锥角从30°增加到150°的过程中,剩余速度先增大、后减小,在90°时达到最高。药型罩厚度为1.5～4mm时,剩余速度变化起伏小;厚度为4～6 mm时,剩余速度开始大幅下降。结论 当锥角为90°时,罩厚为4 mm的药型罩所形成的射流在水中表现最好,形成的射流侵彻深度最长,侵彻水介质10 cm后的剩余速度最大,存速能力最强。     

Analytical Study of the Heat Loss Attenuation by Clothing on Thermal Manikins Under Radiative Heat Loads

For wearers of protective clothing in radiation environments there are no quantitative guidelines available for the effect of a radiative heat load on heat exchange. Under the European Union funded project ThermProtect an analytical effort was defined to address the issue of radiative heat load while wearing protective clothing. As within the ThermProtect project much information has become available from thermal manikin experiments in thermal radiation environments, these sets of experimental data are used to verify the analytical approach. The analytical approach provided a good prediction of the heat loss in the manikin experiments, 95% of the variance was explained by the model. The model has not yet been validated at high radiative heat loads and neglects some physical properties of the radiation emissivity. Still, the analytical approach provides a pragmatic approach and may be useful for practical implementation in protective clothing standards for moderate thermal radiation environments.     

Sustainable development and participatory practices in community forestry: the case of FUNDECOR in Costa Rica

This paper studies the emergence of one particular ‘new’ environmental policy instrument: disclosure of emission and pollution data. Disclosure is part of a relatively new sub‐set of regulatory measures, based on monitoring, transparency, citizen‐empowerment and accountability. It originated in the United States but has recently attracted international attention. The attractiveness of disclosure is obvious; it promises environmental improvement combined with strengthened environmental democracy and community empowerment. By analysing the experiences in the US, and the developments in the Netherlands, this paper seeks to assess the functioning and effectiveness of disclosure. The available empirical evidence suggests that disclosure has a positive impact on the environmental performance of industrial facilities as well as a democratising effect. It is argued that Dutch policy makers wrongfully assume that disclosure cannot work in the Netherlands. The consequence is that citizens are provided with little specific information that cannot be used to put pressure on polluters.     

利用景观梯度法分析张家港市城市景观变化

在遥感与GIS技术平台的支持下,利用景观格局梯度法分析了张家港市各土地利用类型的景观格局及其时空分布特征.研究结果表明,2002-2006年,张家港市城市景观格局总体变化明显,城镇用地增长22.10%,农业用地则减少14.96%.在空间上,呈现出城市一城乡交错带一农业区的变化特征;在时间上,整体样带体现出斑块密度升高、...     

铁炭内电解-厌氧-好氧工艺处理阿维菌素废水的试验研究

血清瓶毒性试验表明 ,AVM对厌氧消化产生强烈的抑制作用。AVM废水经铁炭内电解预处理后 ,COD和AVM的去除率分别达到 19.5 %和 6 8.5 % ,可大大降低废水的毒性。预处理出水再经UASB +生物接触氧化反应器进一步处理 ,当生化系统进水COD为 6 0 0 0— 6 5 0 0mg/L时 ,出水COD为 2 5 0— 2 80mg/L ,总COD去除率达到 95 .6 % ,出水达到生物制药行业排放标准     

利用工业废渣生产水泥新工艺

介绍利用合成氨造气渣、锅炉渣、干煤灰、湿煤灰以及硫酸渣、氟化渣、碎砖等工业废渣生产水泥，并实现水泥无煤生产。     

Effect of oxygen and salt on haemolymph oxygen binding in the brine shrimp Artemia franciscana

The oxygen-binding properties of haemolymph from laboratory-reared Artemia franciscana were investigated in vitro. Adult female brine shrimp without eggs were acclimated to seven different combinations of salinity and oxygen. The oxygen affinity (P₅₀) of unprocessed haemolymph rises with acclimation oxygen partial pressure (PO₂) up to normoxic values, after which no influence of oxygen occurs. The increase in P₅₀ with acclimation PO₂ can be explained by the change in proportion of each of three different haemoglobins in the haemolymph. Salinity acclimation has no effect on haemolymph P₅₀. The effects of the different major salts [NaNO₃, NaCl, Ca(NO₃)₂, Mg(NO₃)₂], pH, and the metal-binding ligand EGTA on the oxygen-binding properties of buffered haemolymph (of shrimp acclimated to 10 salinity) were also studied. Little or no effect of these salts could be found. A small Bohr effect (pH 6.5 to 9.1, =-0.11) was noted. Addition of EGTA caused a significant decrease of the oxygen affinity at concentrations up to 50 mmoll^-1.     

14C-呋喃丹农药在水稻-土壤生态系统中迁移和归宿的研究

研究了~(14)C-呋喃丹在水稻-土壤系统中的吸收、分布、迁移、转化,结果表明,呋喃丹随时间逐渐蓄积于水稻叶尖及边缘,而稻穗部位迁移甚微,收割后糙米中母体残留量仅为0.003ppm.在稻田土、水稻植株、水生植物中主要转化产物为结合态,蜗牛中则以代谢产物为主.呋喃丹有向土壤深层转移的趋向,其转化产物比母体有更强的渗透性,水生植物有较强吸收和富集能力,并很快转化代谢.     

Assessing the nature of psychological contracts: a validation of six dimensions

The purpose of this study is to develop a feature‐oriented assessment of psychological contracts, an underdeveloped approach to psychological contracts. Relying on theoretical frameworks in psychological contract research, industrial relations studies, and a cross‐national study on psychological contracts, we identify six dimensions that capture the nature of psychological contracts: tangibility, scope, stability, time frame, exchange symmetry, and contract level. We validate this expanded conceptualization of psychological contracts by developing a nomological network and testing it in a large, representative sample of 1106 employees. The results indicate the significance of formal contract characteristics and HR practices as two antecedents shaping the nature of psychological contracts. In addition, the hypothesized relationships between the three dimensions of time frame, exchange symmetry, and contract level with affective commitment are confirmed as well as the relationships between tangibility, scope and flexibility with personal control. The results further indicate the importance of assessing both employer and employee obligations given the differential effect of the contract makers. Copyright © 2004 John Wiley & Sons, Ltd.     

Linking the Big Five‐Factors of personality to charismatic and transactional leadership; perceived dynamic work environment as a moderator

In this multi‐source study we investigated the relationships between the Big Five personality traits and both charismatic and transactional leadership behavior, and whether dynamism (the degree that the work environment is deemed dynamic) moderates these relationships. We also tested whether dynamism moderates the relationship between leadership behavior and effectiveness. Personality was measured through self ratings using the NEO‐PI‐R. Subordinates rated their leaders' behavior, and peers and superiors provided ratings of effectiveness. Consistent with trait activation theory, results showed that perceived dynamic work environment moderated the relationships of four of the Big Five‐Factors with both charismatic and transactional leadership. Also, charismatic leadership was positively related to perceived effectiveness, but only in dynamic contexts. Copyright © 2005 John Wiley & Sons, Ltd.