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81.
通过对钒渣经碱浸和酸浸后V2O5回收率的比较,确定了应用H2SO4-氟化物浸出工艺可使渣中钒大部分转变为可溶性盐。分别采用H2SO4-NH4HF2及H2SO4-CaF2浸出工艺从湿冶钒渣中提取V2O5,前者较为满意,V2O5浸出率在65%以上,且氟化物可循环利用。  相似文献   
82.
To assess the capacity of the natural environment for degrading PHB/V, the film-MPN method proposed previously was modified to estimate the numbers of PHB/V degrading microorganisms (degraders) in various environments. The First-Order Reaction (FOR) model was used to determine the appropriate incubation period for the method. Numbers of aerobic PHB/V degraders were estimated in garden soil, paddy field soil, farm soil, river bank soil, infertile garden soil, river water, activated sludge, and seawater by the film-MPN method. Results were compared with those estimated by the clear-zone technique and showed that the film-MPN method was suitable for estimating the numbers of PHB/V degraders in the environments tested. On the other hand, biodegradability of injection molded PHB/V samples was investigated in several kinds of environments. The changes of weight were studied and results showed that biodegradability of PHB/V related to the numbers of PHB/V degraders in similar ecosystem in different regions. In different environments the biodegradability of PHB/V not only related to the number of PHB/V degraders, but also depended on whether there were conditions for the PHB/V degraders to grow and proliferate easily in the environment.  相似文献   
83.
The present work deals with the As(Ⅴ) removal from an aqueous medium by calcined refractory grade bauxite (CRB) as a function of solution pH, time, As(Ⅴ) concentration and temperature. The residual As(Ⅴ) was lowered from 2 mg/L to below 0.01 mg/L in the optimum pH range 4.0-7.0 using a 5 g/L CRB within 3 h contact time. The adsorption data fits well with Langmuir isotherm and yielded Langmuir monolayer capacity of 1.78 mg As(Ⅴ)/g of CRB at pH 7.0. Presence of anions such as silicate and phosphate decreased As(Ⅴ) adsorption efficiency. An increase temperature resulted a decrease in the amount of As(Ⅴ) adsorbed by 6%. The continuous fixed bed column study showed that at the adsorbent bed depth of 30 cm and residence time of 168 min, the CRB was capable of treating 340 bed volumes of As(V) spiked water (C0 = 2 mg/L) before breakthrough (Ce = 0.01 mg/L). This solid adsorbent, although not reusable, can be considered for design of adsorption columns as an efficiency arsenic adsorption media.  相似文献   
84.
V2O5/AC催化剂脱除烟气中SO2的微观动力学研究   总被引:1,自引:1,他引:0  
利用热重分析仪对V2O3/AC脱除SO2的微观动力学进行了研究,考察了催化剂V2O5的含量[w(V2O5)]、反应物SO2和H2O的浓度[ψ(SO2)和ψ(H2O)]及反应温度对催化剂增重分率的影响,并采用微孔填充模型描述V2O5/AC的脱硫行为.模型研究表明:V2O5/AC脱除SO2反应速率由吸附-催化剂表面化学反应控制,SO2和H2O的吸附可用Langmuir-Hinshelwood模型分析.将活性组分表面分率和V2O5/AC的微孔孔容随反应的变化用参数n表示,n类似于反应级数,以表示二者对反应的影响程度.  相似文献   
85.
Vc二步发酵新菌系生长代谢的调节   总被引:2,自引:0,他引:2  
研究了培养基和培养条件对新菌系大、小菌生长地代谢的影响。结果表明:培养基的碳源、葡萄糖/山梨糖浓度比、氮源、生长因子以及起始pH值、通气量等,可以有效地调节2-酮基-L-古龙酸的代谢产生数量,规范新菌系B529-Go.V.6的行为、生理状态,促进大小菌之间的协调,使其达到最佳状态。图2表6参5  相似文献   
86.
87.
利用和达法和石川法对宁波皎口地震的资料进行处理,得到了各台站1993年和1994~1995年初两个时间段内的虚波速度和多台平均波速比。并得出如下结论:(1)樟水流动台1993年虚波速度值异常高,这主要是因为地震波特殊的传播路径以及传播介质在应力积累时产生大量微裂隙引起;而1994年后又呈大幅下降则主要是由于介质裂隙大量充水饱和后引起。(2)与樟水台同处近场的洪山和雪山两个流动台的虚波速度1993年虽也处于较高值,但与樟水台相比却明显要低,这是由于介质波速异常的方向性效应引起。(3)近场虚波速度明显高于远场虚波速度,多台波速比在47级地震前处于中长期低值异常,而地震后回归正常。(4)近场速度特征可作为一项地震预报的追踪指标在皎口地震中应用,但还需进一步完善。  相似文献   
88.
采用定性物理模拟的方法对FM上下V锻造法锻件心部的应力状态进行了实验分析,得出了当上砧宽比W/D_0=0.34时,锻件心部处于三向压应力的结果。实验结果与定量物理模拟相吻合。  相似文献   
89.
Scorodite (FeAsO4·H2O) is a common arsenic-bearing (As-bearing) iron mineral in nearsurface environments that could immobilize or store As in a bound state.In flooded soils,microbe induced Fe(Ⅲ) or As(Ⅴ) reduction can increase the mobility and bioavailability of As.Additionally,humic substances can act as electron shuttles to promote this process.The dynamics of As release and diversity of putative As(Ⅴ)-reducing bacteria during scorodite reduction have yet to be investigat...  相似文献   
90.
NOx emission abatement catalysts V2O5 supported on variousTiO2 including anatase, rutile and mixture of both have beeninvestigated with various physico-chemical measurements such asBET, NH3-TPD, NARP, XRD and so on, and the effect of TiO2 surfaceproperties on the SCR activity of V2O5/TiO2 catalysts was studied.It has been found that the TiO2 surface properties had strongaffect on the SCR activity of V2O5/TiO2 catalysts. The strongeracidic property resulted the higher exposure of active sites aswell as the higher SCR activity.  相似文献   
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