粉煤灰微珠的气力分级原理与实验研究

按气固两相流理论,分析了粉煤灰颗粒在气流中的运动规律,按沉降和平移的原理,利用流幕式气力分级系统对沈阳热电厂粗飞灰进行了多次分级实验,得到了分级效果及分级产量随气速变化的初步规律。

FGX—1型复合式干选机入料粒度与分选效果关系的探讨

ＦＧＸ—１型复合式干选机是一种分选效率较高，适用性较强，具有多次分选功能的新型干选机，为我国西北干旱地区选煤工业的发展提供了一条新途径。本文对该机的入料粒度与分选效果之关系进行了探讨。

全自动淘洗机的应用及选别机理

在分析司家营研山铁矿选矿流程的基础上,通过试验确定全自动淘洗机生产应用的工艺参数,最大可提高精矿品位7.55个百分点。运用重选不同密度粒群沿垂向分层理论,阐明了淘洗机的重选本质符合不同密度粒群在上升介质流中按悬浮体相对密度分层学说,并分析了外加磁场和上升水在选别过程起到的阻止细粒磁性矿物颗粒进入溢流、大大减少等降机率、降低等降现象对沉降分层的影响、增加了矿床稳定性等辅助作用。最后从分析全自动淘洗机的特点和三组磁系作用角度,解释了淘洗机选别的优势。

贵州某厚大溶蚀-裂隙承压含水层储存量计算

在矿区水文地质条件的研究过程中,针对涌水量的计算的难题提出了采用大流量、大降深的群孔抽水试验来求取含水层给水度μ和降落漏斗面积F的值,并根据抽水试验结果,得出等幅下降值,以确定整个漏斗内水位的下降值。同时对储存量和动流量进行区分,计算疏排量和疏排时间的关系,得到了厚大含水层下矿井的排水能力应为25134.8m3/d。

Recent developments in visible-light photocatalytic degradation of antibiotics

With the significant discharge of antibiotic wastewater into the aquatic and terrestrial ecosystems, antibiotic pollution has become a serious problem and presents a hazardous risk to the environment. To address such issues, various investigations on the removal of antibiotics have been undertaken. Photocatalysis has received tremendous attention owing to its great potential in removing antibiotics from aqueous solutions via a green, economic, and effective process. However, such a technology employing traditional photocatalysts suffers from major drawbacks such as light absorption being restricted to the UV spectrum only and fast charge recombination. To overcome these issues, considerable effort has been directed towards the development of advanced visible light-driven photocatalysts. This mini review summarises recent research progress in the state-of-the-art design and fabrication of photocatalysts with visible-light response for photocatalytic degradation of antibiotic wastewater. Such design strategies involve the doping of metal and non-metal into ultraviolet light-driven photocatalysts, development of new semiconductor photocatalysts, construction of heterojunction photocatalysts, and fabrication of surface plasmon resonance-enhanced photocatalytic systems. Additionally, some perspectives on the challenges and future developments in the area of photocatalytic degradation of antibiotics are provided.

Isothermal Crystallization Kinetics of Biodegradable Poly(butylene succinate-co-terephthalate)

The poly （butylene sucinate-co-terphthalate）（PBST） copolyesters with differnet monocs of the PBST has been investigated by differential scanning calorimeter（DSC）.According to Avrami equation,the exponent n for all the copolyesters is independent of the crystallization temperature and content of BT units,and is close to 3,which probably corresponds to the heterogeneous nucleation and a 3-dimensional spherulitic growth.Polarized light micrographs confimed the result.

Reduce the noise of punch press with the equivalent damping

To reduce the noise of the punch press during the punching process, the polyurethane elastomer is used as the damping material. The experiments of reducing noise were made by means of adding the polyurethane elastomer at different positions on the 100 kN and 1 000 kN punch presses. The better effect of reducing noise was obtained. After researching and analyzing a large number of test data, the ″equivalent damping hypothesis″ is put forward. The hypothesis makes the experiment of reducing noise simpler and also more economical. It is estimated that there is a vast application in the research area of vibration control and noise reduction.

Precipitation and Rainwater pH Spatial Distribution in Bahia Blanca and Tandil, Argentina

While the occurrence of rainfall is a regional scale phenomenon, cities influence on precipitation spatial distribution patterns and their characteristics. These influences had been studied for a very long time especially in the Northern Hemisphere. Tandil and Bahia Blanca are middle cities of Argentina located in the south of Buenos Aires province. Both present continental template climate. The aim of this research is to analyze the spatial distribution patterns of precipitation and the rainwater pH values for the period October 2010-September 2011 in Tandil and Bahia Blanca. Gauge rain nets were installed in both cities. In each event of precipitation, amount and pH values were collected. Isohyets plotting were included in the thematic cartography that was made using ArcGis 9.3~ software. Although natural rains are generally considered as being weakly acid, the rainwater pH measurements demonstrated that in both cities the rain is alkaline. Regarding to the spatial distribution of the precipitation amounts, the isohyets of the annual records showed that the highest values were registered in areas of higher elevation while the lowest values were presented in both cities downtown, where the high buildings are concentrated.

On the Production of OH Radical through Plasma Electrolysis Mechanism for the Processing of Ammonia Waste Water

Plasma produced many active species such as OH radical and H radical. As well known, OH radical plays an important role in degrading complex pollutants. This study aims to measure the production of OH radicals and evaluate important parameters that have influent in degradation process of waste water contains ammonia in circulated system and analyze the level of energy consumptions are resulted by this research. The production of OH radical was detected by formation of hydrogen peroxide which was resulted by recombination reaction between OH radicals during plasma electrolysis process. From the measured concentration of hydrogen peroxide, obtained concentration of OH radical is 2,020 ppm. The depth of anode, applied voltage and ammonia initial concentration have affected ammonia degradation percentage and energy consumption level. The highest result for ammonia degradation percentage is 63.2% which gets from applied voltage 700 V, with depth of anode 1 cm, initial concentration of ammonia 100 ppm, and lowest energy consumption of 110 KJ/mmol.

A simplified approach for settlement calculation of pile groups considering pile-to-pile interaction in layered soils

A simplified approach is presented for the analysis of the settlement of vertically loaded pile groups. In order to simulate the nonlinear pile-to-pile interaction in pile groups, the soils along the piles are assumed to behave as a series of nonlinear springs subjected to the shaft shear stress at the pile/soil interface. Considering the displacement reduction induced by the pile-to-pile interaction, the shear-deformation method is adopted to approximate the displacement field of the layered soils around the piles, and the equivalent stiffness of the springs is obtained. Furthermore, the load-settlement response of pile groups is deduced by modifying the load-transfer functions to account for the pile-to-pile interaction. The settlements of a laboratory pile groups computed by the presented approach are in a good agreement with measured results. The analysis on Contrastive parameters shows that the settlements of pile group decrease with the increase of the pile space and pile length, and the part of piles exceeding the critical pile length has little contribution to the beating capacity of the pile groups.

Strengthening and stress drop of ultrafine grain aluminum after annealing

Ultrafine grain pure aluminum was produced by equal channel angular pressing and cold rolling, the deformed aluminum was annealed at 200 ℃ for 1 h. The tensile curves of deformed and annealed aluminum show that yield strength of deformed aluminum increases by 100%-300% and its elongation decreases by about 20%. After low temperature annealing, strength of annealed aluminum increases by 20% and elongation decreases by over 50%, the recovery of dislocations may be the main cause of annealing strengthening. In addition, there is an abrupt stress drop in the tensile curves of annealed aluminum and the formation of shear band is responsible for it.

Feasible SQP Descent Method for Inequality Constrained Optimization Problems and Its Convergence

In this paper,the new SQP feasible descent algorithm for nonlinear constrained optimization problems presented,and under weaker conditions of relative,we proofed the new method still possesses global convergence and its strong convergence.The numerical results illustrate that the new methods are valid.

Heavy Metals in Dust Deposition in the Vicinity of Coal Ash Disposal Site Divkovici Ⅱ

DD （Dust deposition） was monitored over a 6-month period （April to September, 2011） at four sites located in villages near CADDⅡ（coal ash disposal site Divkovici Ⅱ）, one inside recultivated CADDⅠ （coal ash disposal site Divkovici Ⅰ） and at one in the middle of forest barrier as control site. The main aim of this paper is to perform monitoring of air dust pollution in the area by measuring of dust deposition, different metals associated with it, and probable adverse effects on human health. Concentrations of metals were measured by using Perkin-Elmer model Inductively Coupled Plasma and statistically evaluated with SPSS 17.0 statistical program. There was a correlation between some metals （Mn, Mo and Pb） and DD distribution. The daily limit values for concentration of DD proposed by national ＂Regulations on air quality＂ （200 mg/m^2d average annual value and 350 mg/m^2d high value） exceed at three measuring sites. The average maximum content of DD was 684.8 mg/m^2d downwind of CADDII, and the average minimum was 46.8 mg/m^2d at measuring site F. Concentrations of pollutants hazardous to the environment as Ni, Cr, Cu, Mo, Mn and Pb vary from one site to another.

The establishment of a new deliverability equation considering threshold pressure gradient

The flowing mechanism of a low permeability gas reservoir is different from a conventional gas reservoir,especially for that with higher irreducible water saturation the threshold pressure gradient exists. At present,in all the deliverability equation,the additional pressure drop caused by the threshold pressure gradient is viewed as constant,but this method has big error in the practical application. Based on the non-Darcy steady flow equation,the limited integral of the additional pressure drop is solved in this paper and it is realized that the additional pressure drop is not a constant but has something to do with production data,and a new deliverability equation is derived,with the relevant processing method for modified isochronal test data. The new deliverability equation turns out to be practical through onsite application.

Genetic analysis of land subsidence in Anshan

Land subsidence is a complex geological phenomenon which is concerned by the researchers at home and abroad. In this paper,the observation data from Anshan Second Order Leveling during 1987-[KG-*7]-1994,combined with the area of environmental engineering geology and geological conditions analysis shows that land subsidence in Anshan City is closely related to active tectonics,Quaternary strata and groundwater exploitation.