水丰水库中方侧再扩新电厂可行性探讨

鸭绿江干流已建成的４座水电站中，朝方掌握管理水丰和渭源两座大电站的运行权，中方得不到对等供电，给中方经济造成很大损失。因此，考虑研究是否能在水丰水库中方侧再扩一座发电站，增加发电能力，扭转不利局面。本文即是对扩建新电厂的可行性作初步探讨。

Effect of temperature on soil-water characteristics and hysteresis of compacted Gaomiaozi bentonite

Laboratory tests under different constraint conditions were carried out to obtain the soil-water retention curves(SWRCs) of highly-compacted confined/unconfined Gaomiaozi(GMZ) bentonite at 20,40 and 80 ℃,respectively. The effect of temperature on the soil-water characteristics of the highly-compacted GMZ bentonite was analyzed. The results show that the water retention capacity of the highly-compacted GMZ bentonite decreases as the temperature increases under unconfined and confined conditions. At a certain temperature,the constraint conditions have little influence on the water retention capacity of the compacted bentonite at high suction,but the water retention capacity of the confined specimen is lower than that of the unconfined specimen at low suction. Under unconfined conditions,the hysteretic behaviour of the compacted bentonite decreases with increasing temperature. At high suction(>4 MPa) ,the hysteretic behaviour of the unconfined bentonite tends to increase with the decrease of the suction. In summary,the hysteretic behaviour of the compacted bentonite is not significant.

A Review of Colloid Transport in Fractured Rocks

Recent recognition of colloid and colloidassociated transport of strongly sorbing contaminants in fractured rocks highlights the importance of exploring the transport behavior of colloids under conditions prevailing in the field.The rapid transport of colloids through fractured rocks-as affected by the hydraulic properties of the flow system,the properties of fracture surface and the geochemical conditionshas not been sufficiently elucidated,and predictions of colloid transport through fractures have encountered difficulties,particularly at the field scale.This article reviews the current understanding of the mechanisms and modeling of colloid transport and retention in fractured rocks.Commonly used experimental techniques and approaches for conducting colloid transport experiments at different scales,ranging from the laboratory to the field scale,are summarized and commented upon.The importance of various interactions(e.g.,dissolution,colloid deposition,generation,mobilization and deposition of filling materials within fractures) between the flowing solution and the fracture walls(in many cases,with skin or coating on the host rock at the liquid-solid interface) has been stressed.Colloid transport through fractures of high heterogeneity has not yet been well understood and modeled at the field scale.Here,we summarize the current knowledge and understanding accumulated in the last two decades in regard to colloid and colloidassociated transport through fractures.Future research needs are also discussed.

Drainage feature about coalbed methane wells in different hydrogeological conditions in Fanzhuang area

It is an important guarantee to enhance the production of coalbed methane （CBM） and reduce the project invest- ment by finding out the drainage feature about CBM wells in different hydrogeological conditions. Based on the CBM explora- tion and development data on the Fanzhuang block in southeast Qinshui Basin and combined with the seepage principle and lithology on the roof and the bottom coalbed, the mathematical model of integrated permeability was established. By perme- ability experiments of the different lithologies on the roof and the floor within the 20 m range combined with the log curves, the integrated permeability of different lithological combinations were obtained. The starting pressure gradient and permeabi- lity of the roof and the floor for different lithologies was tested by ＂differential pressure-flow method＂. The relationships be- tween the starting pressure gradient and the integrated permeability were obtained. The critical distance of limestone water penetrating into coal reservoirs was calculated. According to the drainage feature of CBM wells combined with the drainage data of some CBM wells, the results show that, when limestone water can penetrate into coal reservoirs, the daily water production is high and the daily gas production is low although there is no gas at the beginning of the drainage process, the CBM wells stop discharging water within 6 months after the gas began to come out, and the gas production is steadily improved. When limestone water can not penetrate into coal reservoirs, the daily water production is low and the daily gas production is high at the beginning of the drainage process, and it almost stops discharging water after some time when the gas come out, the daily gas production increases, and the cumulative water production is much lower.

Photocatalytical Inactivation of Enterococcus faecalis from Water Using Functional Materials Based on Natural Zeolite and Titanium Dioxide

The functional materials based on natural zeolite （clinoptilolite）, TiO2-zeolite and Ag-TiO2-zeolite have been successfully synthesized by solid-state reaction in fast-hydrothermal conditions. The obtained functional materials were investigated by X-ray diffraction （XRD）, FT-1R （Fourier transform infrared） spectroscopy, DRUV-VIS （diffuse reflectance ultraviolet-visible） spectroscopy, BET （Brunauer-Emmett-Teller） and SEM/EDX （scanning electron microscope/energy dispersive X-ray spectrometer） analyses. The XRD results indicated that the clinoptilolite structure has a good thermal stabilization after the fast-hydrothermal treatment. Also, the high specific surface area about 92.55 m^2.g^-1 was noticed for Ag-TiO2-zeolite functional material. The presence of dopants was evidenced from EDX spectra. The enhanced bactericidal activity of Ag-TiO2-zeolite catalyst is proved through damaging of Enterococcusfaecalis colonies under visible irradiation, at different material doses and irradiation times.

Effects of different factors during the de-silication of diaspore by direct flotation

Most of the bauxite resources in China are kaolinite-diaspore bauxite of middle to low grade, with a fine dissemination, and are difficultly separated. Direct flotation de-silication has been shown to be an effec- tive method for de-silication of diaspore. In this study the effect of different factors, including pulp tem- perature, density, pH value, depressant, and collector dosage, on direct flotation of diaspore were investigated by laboratory experiments. The optimum conditions were identified and the flotation perfor- mance was improved. The results show that under optimum conditions （a pulp temperature around 40℃, a pulp density from 30% to 33g, a pH value from 9.0 to 10.0, an air flow rate of 0.5 m3/（m2 rain）, a dispersant level from 35 to 70 g/t, and a collector level around 1000 g/t） an AI/Si ratio of 6.97 is obtained starting from an initial Al/Si ratio of about 4.71. The recovery of A1203 under these conditions was 86.94%.

Performance of Water and Mercury Triple Points Reference Cells under Adiabatic Conditions

Two new miniature metallic sealed-cells containing the triple point of water, WTP （273.16 K） and the triple point of mercury, HgTP （234.3156 K） have been constructed for the realization of the International Temperature Scale of 1990 （ITS-90） at the National Institute of Standards （NIS-Egypt）. The two new cells, in addition to a previously realized argon and oxygen triple point cells, will provide facilities for the calibration of capsule-type standard platinum resistance thermometers （CSPRTs） at one single run. Many phase transition plateaux were carried out and compared to the laboratory large reference cells using the same thermometers in order to test the performance of the new cell.

Influence of axial distance on pre-whirl regulation by the inlet guide vanes for a centrifugal pump

The valuation of the hydraulic performance of a centrifugal pump with pre-whirl regulation of the inlet guide vanes was studied experimentally by varying the pre-whirl angle from -60° to 60° with distances between the inlet guide vanes and the impeller inlet of 280 mm, 380 mm and 460 mm. The efficiency-flow curves and the characteristic curves were obtained for the pump for various operation conditions. The experiment results demonstrated that the pre-whirl regulation widened the high efficiency zone and improved the hydraulic performance for off-design conditions with the proper pre-whirl angle. The axial distance between the inlet guide vanes and the impeller inlet influenced the pre-whirl regulation effect of the inlet guide vanes with the best pre-whirl regulation effect obtained for an axial distance of 380 mm. These results showed that an appropriate axial distance between the inlet guide vanes and the impeller inlet can improve the fluid flow at the impeller entrance with pre-whirl regulation for centrifugal pumps.

An Experimental Study on the Performance of a Stainless Steel-Water Loop Heat Pipe under Natural Cooling Condition

Aiming to improve the thermal characteristics of modern electronics, we experimentally study the performance of a stainless steel/water loop heat pipe(LHP) under natural cooling condition. The LHP heat transfer performance, including start-up performance, temperature oscillation and total thermal resistance at different heat loads and with different incline angles have been investigated systematically. Experimental results show that at an optimal heat load(i.e. 60 W) and with the LHP being inclined 60 to the horizontal plane, the total thermal resistance is lowered to be ~0.24 K/W, and the temperature of evaporator could be controlled steadily at around 90 C.