中国银行业不良资产与中国金融体系的未来

本文针对中国银行业的不良资产是否会对中国金融体系构成威胁的问题，提出了如下观点：中国银行业的不良资产主要是政策性贷款，是在经济体制转型中逐渐形成的，其形成原因主要是制度原因；不良贷款的处置损失将在未来由国家财政、中央银行和国有银行之间分担，未来分担损失降低了对当前金融体系的冲击；在对中日两国银行不良贷款处置问题进行比较后，发现中国由于拥有国家政府担任主导者和终极责任承担者的角色，与日本相比，中国不良资产的处置进程迅速并且前景甚佳；随着中国的经济改革进程，中国人民的财富安全性和经济安全性在不断提高，这将有助于中国金融体系的稳定和中国经济的长期增长。     

政府间财政转移支付对发展中国家的启示

本文考察了在设计政府间财政转移支付制度中出现的一些核心问题，总结了许多国家采取的做法，并侧重于发展中国家的做法。由于国与国之间的情况和目标有差别，所以并不存在单一的、普遍适用的转移支付模式。但世界范围的经验表明，如果要提供更有效率的服务，转移支付必须这样设计：即接受转移支付的政府必须拥有清晰的授权、足够的资源以及充分的决策灵活性，并且要对结果负责。     

La Ville de Quèbec et al planification stratègique

ＬａＶｉｌｌｅｄｅＱｕ啨ｂｅｃ，ｃａｐｉｔａｌｅｄｅｌａ ｐｒｏｖｉｎｃｅｄｕｍ毢ｍｅｎｏｍ，ｅｓｔｓｉｔｕ啨ｅｄａｎｓｌ＇ｅｓｔｄｕＣａｎａｄａ，ｓｕｒｌｅｓｒｉｖｅｓｄｕｆｌｅｕｖｅＳａｉｎｔ -Ｌａｕｒｅｎｔ，ｕｎｅｄｅｓ ｇｒａｎｄｅｓｖｏｉｅｓｎａｖｉｇａｂｌｅｓｄｅｌ＇Ａｍ啨ｒｉｑｕｅｄｕＮｏｒｄ．ＢｅｒｃｅａｕｄｅｌａｃｉｖｉｌｉｓａｔｉｏｎｆｒａｎｃａｉｓｅｅｎＡｍ啨ｒｉｑｕｅ，Ｑｕ啨ｂｅｃｅｓｔｕｎｅｖｉｌｌｅｆｒａｎｃｏｐｈｏｎｅｒｅｃｏｎｎｕｅｐｏｕｒｓｏｎｅｘｃｅｌｌｅｎｔｅ…     

美洲潮汐发电园区的开发前景

因种种原因,目前开发利用的潮汐能仅占世界潮汐蕴藏总量的极小一部分,而潮汐发电园区(TG)提供了一种全新的解决方案。重点分析了在美洲开发TG的可行性,证明了TG不仅在加拿大或阿拉斯加这样的高潮差地区具有成本效益,而且在阿根廷这样的中潮差地区,甚至在巴西这样潮差只有3 m的地区也同样具有成本效益。     

第三代硝化移动床生物膜反应器废水处理效果研究

研究了移动床生物膜反应器(MBBR)对废水的处理效果及固体颗粒物的分离作用,包括对COD和氨氮的去除,及其高曝气和硝化作用所产生的固体颗粒物的沉降、粒径分布等。结果表明:MBBR对COD的去除率能达到33%~59%,明显优于对照反应器;MBBR对废水中的氨氮具有很强的硝化作用,氨氮去除率达83.05%,远高于对照反应器。MBBR出水中的总悬浮物(TSS)与原废水相比,增加了约50%,同时,MBBR出水中的挥发性悬浮物(VSS)/TSS高于原废水和对照反应器出水,进一步说明MBBR出水中TSS有相当一部分来自生物膜脱落。另外,曝气能增加较大颗粒物所占的比例,从而提高了悬浮固体的沉降性能。因此,相对于传统的废水处理方法,MBBR具有可靠的除碳除氮效果。     

Elimination and accumulation of polycyclic aromatic hydrocarbons in urban stormwater wet detention ponds

The concentrations of polycyclic aromatic hydrocarbons (PAHS) in water and sediments of seven wet detention ponds receiving urban stormwater were investigated. The ponds comprised traditional wet detention ponds with a permanent wet volume and a storage volume as well as ponds that were expanded with sand filters and other means to improve the removal of micropollutants. The concentrations of sigmaPAH in the sediments varied between 6 +/- 5 and 2,222 +/- 603 ng g(-1) dry weight (mean +/- standard deviation), and were highest in the ponds with lower pond volume per catchment area and did not clearly reflect different activities in the catchments. In general, the concentrations of PAHS in the sediments decreased from inlet to outlet, especially in the systems with good conditions for sedimentation such as systems with flow perpendicular sand dikes and extensive submerged vegetation. High molecular weight PAHs were predominant in the sediments indicating the pyrogenic origin of the PAHS. There was no correlation between PAH species concentrations in water or sediments and their hydrophobicity (log K(ow)). PAH concentrations in water fluctuated in response to intensity and frequency of rain events, whereas concentrations in the sediments integrated the pollutant load over time. Pond systems expanded with sand filters and other technologies to enhance removal of micropollutants consistently had concentrations of PAHS in the effluents below the detection level.     

Simultaneous domestic wastewater treatment and renewable energy production using microbial fuel cells (MFCs)

Microbial fuel cells (MFCS) can be used in wastewater treatment and to simultaneously produce electricity (renewable energy). MFC technology has already been applied successfully in lab-scale studies to treat domestic wastewater, focussing on organic matter removal and energy production. However, domestic wastewater also contains nitrogen that needs to be treated before being discharged. The goal of this paper is to assess simultaneous domestic wastewater treatment and energy production using an air-cathode MFC, paying special attention to nitrogen compound transformations. An air-cathode MFC was designed and run treating 1.39 L d(-1) of wastewater with an organic load rate of 7.2 kg COD m(-3) d(-1) (80% removal efficiency) and producing 1.42 W m(-3). In terms of nitrogen transformations, the study demonstrates that two different processes took place in the MFC: physical-chemical and biological. Nitrogen loss was observed increasing in line with the power produced. A low level of oxygen was present in the anodic compartment, and ammonium was oxidised to nitrite and nitrate.     

Experimental study of a novel hybrid constructed wetland for water reuse and its application in Southern China

A new type of hybrid constructed wetland (CW), consisting of both vertical-baffled flow wetland (VBFW) and horizontal subsurface flow wetland (HSFW), has been deployed in Southern China to naturally accelerate the removal of organic matter and nitrogen. The hybrid CW system is characterised by a combination of continuous baffled flow vertical wetland and 'S' pattern horizontal subsurface flow wetland with natural aeration ditches to increase the concentration of dissolved oxygen in the HSFW bed. An internal circulatory system from the HSFW effluent back to the VBFW may optionally be operated to enhance the biological denitrification effect. Cyperus alternifolius is the main macrophyte in the wetland bed. The performance of the hybrid CW was studied with a pilot-scale system and three full-scale systems for municipal sewage treatment in Southern China. The results suggest that this new hybrid CW can achieve removal efficiencies of chemical oxygen demand, suspended solids, ammonia nitrogen, total nitrogen, and total phosphorus of better than 83.6, 95.0, 71.7, 64.5 and 68.1% respectively, with a specific wetland bed area of 0.70-0.93 m(2) PE(-1). The mean effluent concentrations of these parameters would meet the regulatory discharge limits for wastewater treatment systems (GB18918, 2002) and reuse in the context of agricultural irrigation solutions in China.     

Microbial community composition and reactor performance during hydrogen production in a UASB reactor fed with raw cheese whey inoculated with compost

This study investigated the microbial community developed in a UASB reactor for hydrogen production and correlated it to reactor performance. The reactor was inoculated with kitchen waste compost and fed with raw cheese whey at two organic loading rates, 20 gCOD/Ld and 30 gCOD/Ld. Hydrogen production was very variable, using an OLR of 30 gCOD/Ld averaged 1.0 LH(2)/Ld with no methane produced under these conditions. The hydrogen yield was also very variable and far from the theoretical. This low yield could be explained by selection of a mixed fermentative population with presence of hydrogen producing organisms (Clostridium, Ruminococcus and Enterobacter) and other non-hydrogen producing fermenters (Lactobacillus, Dialister and Prevotella). The molecular analysis of the raw cheese whey used for feeding revealed the presence of three predominant organisms that are affiliated with the genera Buttiauxella (a low-yield hydrogen producer) and Streptococcus (a lactic acid-producing fermenter). Although these organisms did not persist in the reactor, the continuous addition of these fermenters could decrease the reactor's hydrogen yield.