金属塑性成形计算机模拟的若干进展

结合作者正在开展的研究工作，综述了金属生性成形计算机模拟技术近年来的一些重要进展，主要涉及模拟计算方法，利用模拟技术的工艺优化设计、材料组织性能演化的模拟以及模拟软件设计方法等。     

重庆城区大气悬浮颗粒物（TSP）金属元素特征

分析了重庆城区１９９２年三个采样点（市中区、江北区、大渡口区）大气环境ＴＳＰ中１０种金属元素浓度，结果表明：三个采样点之间及不同季节，金属元素浓度分布存在差异；重庆城区大气ＴＳＰ中金属元素浓度高于北京、上海等城市，并探讨了产生的原因。     

Effects of Fe2O3, organic matter and carbonate on photocatalytic degradation of lindane in the sediment from the Liao River,China

Fourteen sediment samples with different content of Fe₂O₃ were collected from the lower reaches of the Liao River in China. The photodegradation of lindane on the surfaces of these sediments was investigated to observe the effects of Fe₂O₃ and other photoinducable substances, such as TiO₂ and organic substances, on photodegradation of lindane. A partial least-squares (PLS) analysis model was developed to find out the statistical relationship between the photodegradation and the contents of these photoinducable substances. It was concluded from the PLS analysis that inorganic carbon and organic carbon have negative effects, whereas Fe₂O₃ and TiO₂ accelerate the photodegradation of lindane in the sediment samples when 365 nm UV light was used as light source. In all cases of the experiments, the photodegradation of lindane in the sediment samples were fitted for pseudo-first-order kinetics.     

Effect of particle morphology on metal dust deflagration sensitivity and severity

Combustible dust explosions continue to present a significant threat toward industries processing, storing, or pneumatically conveying metal dust hazards. Through recent years, investigations have observed the influence of particle size, polydispersity, and chemical composition on dust explosion sensitivity and severity. However, studies characterizing the effect of particle shape (or morphology) on metal dust explosibility are limited and merit further consideration. In this work, high-purity aluminum dust samples of three unique particle morphologies were examined (spherical granular, irregular granular, and dry flake). To maintain consistency in results obtained, all samples were procured with similar particle size distribution and polydispersity, as verified by laser diffraction particle size analysis. Scanning electron microscopy (SEM) imaging and Brunauer-Emmett-Teller (BET) experiments were executed to confirm supplier claims on morphology and to quantify the effective surface area associated with each sample, respectively. Investigations performed in a Kühner MIKE3 minimum ignition energy apparatus and a Siwek 20 L sphere combustion chamber resulted in the direct characterization of explosion sensitivity and severity, respectively, as a function of suspended fuel concentration and variable particle morphology. Recommendations to standard risk/hazard analysis procedures and to existing design guidance for the mitigation of deflagrations that originate from ignition of distinctively processed metal dust fuels have been provided.     

Review on utilization of biochar for metal-contaminated soil and sediment remediation

Biochar is a carbon-neutral or even carbon-negative material produced through thermal decomposition of plant- and animal-based biomass under oxygen-limited conditions. Recently, there has been an increasing interest in the application of biochar as an adsorbent, soil ameliorant and climate mitigation approach in many types of applications. Metal-contaminated soil remediation using biochar has been intensively investigated in small-scale and pilot-scale trials with obtained beneficial results and multifaceted effects. But so far, the study and application of biochar in contaminated sediment management has been very limited, and this is also a worldwide problem. Nonetheless, there is reason to believe that the same multiple benefits can also be realized with these sediments due to similar mechanisms for stabilizing contaminants. This paper provides a review on current biochar properties and its use as a sorbent/amendment for metal-contaminated soil/sediment remediation and its effect on plant growth, fauna habits as well as microorganism communities. In addition, the use of biochar as a potential strategy for contaminated sediment management is also discussed, especially as regards in-situ planning. Finally, we highlight the possibility of biochar application as an effective amendment and propose further research directions to ensure the safe and sustainable use of biochar as an amendment for remediation of contaminated soil and sediment.     

污水灌溉对沈阳市农田土壤中重金属含量的影响

通过对 2个灌区上、中、下游土壤中重金属的监测分析 ,得出虽然污水灌溉已停止 ,但其对土壤的污染仍然存在 ,重金属在土壤中累积并被作物吸收后随食物链进入人体 ,危害人类健康     

高效液相色谱法在无机分析中的应用

本文综述了高效液相色谱法在无机分析中的应用进展。分别介绍了正相、反相、离子对、离子交换、排阻和胶束流动相等液相色谱法在有机金属化合物、金属络合物、无机阳离子和阴离子分离及测定上的实际应用。     

降水对金属材料的大气腐蚀速率影响研究

对甘肃省陇南地区、兰州市和新疆独山子的金属材料的大气腐蚀速率进行了分析测定,研究并比较了酸雨和非酸雨区的大气腐蚀速率,研究和探讨了相互关系。     

Metal release/accumulation during the decomposition of Potamogeton crispus in a shallow macrophytic lake

Changes in metal concentrations in the litter of Potamogeton crispus were monitored during a consecutive 40-day in situ decomposition experiment using the litterbag method.The accumulation index was calculated and used to indicate the changes in the metals in litter.The results showed that the concentrations of Al,Cd,Cr,Fe,Mn,and Pb in litter increased significantly during the decomposition,while Cu and Zn concentrations decreased dramatically.Significant positive correlations were found between the concentrations of Al,Cr,Fe,and Mn and between Cu and Zn.Moreover,Cu and Zn both negatively correlated with Al and Fe.The remaining dry mass was negatively correlated with Al and Fe concentrations but positively correlated with Cu and Zn concentrations.Generally the accumulation index values of metals other than Al were less than one,indicating that the litter of P.crispus acted as a source of metals to the surrounding water body.Al was the only metal that showed continuous net accumulation in litter.The net accumulation of Fe and Mn in litter during the last 10 days of the experiment may indicate the precipitation of Feand Mn-oxides.It was estimated that 160 g/m~2(dry weight)P.crispus was decomposed in40 days.This was equivalent to releasing the following amounts of metals:0.01 mg Cd,0.03 mg Cr,0.71 mg Cu,0.55 mg Mn,0.02 mg Pb and 13.8 mg Zn into surrounding water,and accumulating 149 mg Al and 11 mg Fe,in a 1 m~2 area.     

海口市蔬菜土壤重金属含量特征研究

采用野外调查法结合实验室分析法对海口市郊区蔬菜土壤重金属含量特征进行研究,测定了Cr、As、Cd、Cu、Zn、Pb、Ni、和Hg 8种重金属全量、有效态含量及蔬菜土壤pH值和有机质含量,重金属全量与有效态含量间的相关性及土壤pH值,有机质含量与蔬菜土壤中重金属全量间的相关性。结果表明,海口市蔬菜土壤中各种重金属均表现出一定的累积趋势;8种重金属元素有效态含量与全量呈正相关,重金属有效态占全量比例在1.86%~13.47%之间,其中Cd、Pb和Hg较高,分别为13.47%、10.23%和8.42%,三者表现出较大的潜在污染风险;土壤p H值和有机质含量与重金属全量表现出一定的相关性,相关性大小与重金属种类有关;重金属全量并不能全面正确评价土壤的环境效应,对蔬菜土壤重金属污染程度进行评价时,应把重金属全量、有效态含量与土壤基本理化性质结合起来进行研究。