管道分质供水消毒副产物及其安全性评价

消毒副产物是饮用水中应主要控制的毒害物。然而，管道分质供水中消毒副产物特征及污染水平很少研究。以某一管道分质供水工程为例，对其中消毒副产物进行了详细研究。研究结果表明，管道分质供水消毒副产物在量与质上与其源水自来水存在很大差别。在管道分质供水中消毒副产物量少，一般不到自来水的1／10，且主要是一些毒性较低、与供水管材有关的溶出物。据此计算出管道分质供水由消毒副产物引起的致癌风险性一般不到其源水的1／10，其安全性大大提高。     

Preparation and photocatalytic performance study of dual Z-scheme Bi2Zr2O7/g-C3N4/Ag3PO4 for removal of antibiotics by visible-light

At present, the high re-combination rate of photogenerated carriers and the low redox capability of the photocatalyst are two factors that severely limit the improvement of photocatalytic performance. Herein, a dual Z-scheme photocatalyst bismuthzirconate/graphitic carbon nitride/silver phosphate (Bi₂Zr₂O₇/g-C₃N₄/Ag₃PO₄ (BCA)) was synthesized using a co-precipitation method, and a dual Z-scheme heterojunction photocatalytic system was established to decrease the high re-combination rate of photogenerated carriers and consequently improve the photocatalytic performance. The re-combination of electron-hole pairs (e⁻ and h⁺) in the valence band (VB) of g-C₃N₄ increases the redox potential of e⁻ and h⁺, leading to significant improvements in the redox capability of the photocatalyst and the efficiency of e⁻-h⁺ separation. As a photosensitizer, Ag₃PO₄ can enhance the visible light absorption capacity of the photocatalyst. The prepared photocatalyst showed strong stability, which was attributed to the efficient suppression of photo-corrosion of Ag₃PO₄ by transferring the e⁻ to the VB of g-C₃N₄. Tetracycline was degraded efficiently by BCA-10% (the BCA with 10 wt.% of AgPO₄) under visible light, and the degradation efficiency was up to 86.2%. This study experimentally suggested that the BCA photocatalyst has broad application prospects in removing antibiotic pollution.     

聚合氯化铝与聚磷硫酸铁絮凝除藻比较研究

针对武汉市莲花湖湖水,采用聚合氯化铝(PAC)和聚磷硫酸铁(PPFS)进行絮凝实验,比较了两种无机絮凝剂的絮凝效果及原水处理前后藻类群落变化。主要结论如下:①PPFS与PAC的最佳投加量分别为1.5mg/L、2.0mg/L;②PPFS在去除藻类细胞、浊度和色度方面均优于PAC,当PPFS投加过量时,因水体中Fe3+过量分布,使水样色度去除率下降;③PPFS絮凝处理微囊藻为主体的水华原水时,其效果比PAC更好。本文研究后表明:PPFS是一种新型高效絮凝剂,其絮凝性能明显优于PAC,当水体以微型藻类为主时,可使用PPFS以替代PAC,能提高絮凝效果。     

Performance evaluation of microbial fuel cell for landfill leachate treatment: Research updates and synergistic effects of hybrid systems

Over half of century, sanitary landfill was and is still the most economical treatment strategy for solid waste disposal, but the environmental risks associated with the leachate have brought attention of scientists for its proper treatment to avoid surface and ground water deterioration. Most of the treatment technologies are energy-negative and cost intensive processes, which are unable to meet current environmental regulations. There are continuous demands of alternatives concomitant with pos...     

硝基多环芳烃致突变性构效关系研究

应用逐步判别分析法，对８０种硝基多环芳烃致突变性构效关系进行了研究，７２个训练样本判别回代符合率为９０．２８％，８例预测样本正确分类率为１００％，累计正确分类率达９１．２５％。     

Pressure characteristics and dynamic response of coal mine refuge chamber with underground gas explosion

Coal mine refuge chambers are new devices for coal mine safety which can provide basic survival conditions after gas explosion. In order to simulate the propagation of underground methane/air mixture blast wave, and check structural safety of coal mine mobile refuge chamber, an underground tunnel model and a refuge chamber model have been established based on explicit nonlinear dynamic ANSYS/LS-DYNA 970 program. Results show that the reflected wave pressure on the impact surface was about two times higher than that on the incident one. The relationship between the pressure fields of the chamber was analyzed. The maximum pressure of gas explosion reached about 0.71 MPa, and the pulse width was 360 ms. The maximum absolute displacement and stress occurs at the main door center and the connection of stiffeners and the front plate, respectively. The entire coal mine mobile refuge chamber was in elastic state and its strength and stiffness meet the safety requirements. The cabin door, the front plate and the connecting flange at cabin back as well as the stiffeners on each side were the most critical components. Suggestions were put forward for the refuge chamber.     

Structure of flames propagating through aluminum particles cloud and combustion process of particles

Structure of flames propagating through aluminum particles clouds and combustion processes of the particles have been examined experimentally to understand the fundamental behavior of a metal dust explosion. The combustion process of individual aluminum particles in a flame propagating through the aluminum particles cloud has been recorded by using a high-speed video camera with a microscopic optical system, and analyzed. The flame is shown to be consisted of a preheat zone of about 3 mm thick, followed by a combustion zone of 5–7 mm thick. In the combustion zone, discrete gas phase flames are observed around each aluminum particle. Also an asymmetric flame around a particle is observed, which might be caused by an ejection of aluminum vapor from a crack of oxide shell surrounding the particle.     

Impact of a shock wave on a structure on explosion at altitude

The number of explosive attacks on civilian buildings has recently increased and the pattern of damage inflicted on structures when an explosion takes place at altitude remains quite difficult to predict. The primary aim of the work reported here was to enhance the understanding of how blast waves from an explosion at altitude interact with the ground and with a structure. Small-scale experiments were conducted using a propane–oxygen stoichiometric mixture as explosive. This approach is original because it models high-explosive detonation in terms of gaseous charge explosion using TNT equivalents. Several non-dimensional laws are expressed and validated by experiments. These relationships allow determination of the propagation of a blast wave and its interaction with a structure as a function of the position of the explosive charge when the explosion occurs at altitude. Then, from knowledge of the blast loading, using Hopkinson's scaling law and TNT equivalents, we can predict the interaction of blast waves with the ground and a structure on a real scale. Simulations were performed using the Autodyn code, and good correlation with the experimental results was obtained.     

基于投资结构视角的企业环保投资与财务绩效

通过回归分析法研究造纸与印刷业上市公司的环保投资与财务绩效的相关性,发现两者之间呈显著的正向线性关系。将环保投资按不同结构分类,发现污染预防投资比末端治理投资带来的财务绩效更明显,环保固定资产投资比技术投资在短期内带来的财务效益更明显。