用P507萃取剂分离磷矿石中的稀土元素研究

研究了用P507萃取法分离磷矿石中的稀土元素;分离的稀土元素用PMBP-苯萃取分离,用偶氮胂Ⅲ光度法测定．此方法应用于测定磷矿石中稀土元素含量,其萃取回收率为91．5％．相对标准偏差为0．59％．     

Particulate flow modelling in a spiral separator by using the Eulerian multi-fluid VOF approach

The Euler-Euler model is less effective in capturing the free surface of flow film in the spiral separator,and thus a Eulerian multi-fluid volume of fluid(VOF) model was first proposed to describe the particulate flow in spiral separators. In order to improve the applicability of the model in the high solid concentration system, the Bagnold effect was incorporated into the modelling framework. The capability of the proposed model in terms of predicting the flow film shape in a LD9 spiral separat...     

STUDY OF ADSORPTION OF RARE EARTH ELEMENTSBY FERRIC OXIDE GEL

Thereexistthreeformsofrareearthelements(REE)intheknownnaturalores:mineralcrystallineform,isomorphousreplacementformandexchangeableionicadsorptionform.Resently,however,anewkindofsecondaryoreofrareearthelementswidelydistributedintheoxidationzoneofthelargerbast--naesitedepositshasbeendiscoveredintheSouthwestofChinaandVietnam.Theneworelookslikeblackearthyefflorescence,andmainlyconsistsofamorphousFe--MnoxideandSt--Aloxide.Theformeraccountsfor74.14%(volumerate)andthelatter25.86%(volumerate).Ther…     

ICP—AES直接测定地质样品中微量稀土元素

研究了基体元素对15个稀土元素的干扰,优化了ICP的工作参数,采用Na2O2碱熔处理样品,加入三乙醇胺,EGTA络合干扰离子,计算机离峰背景校正消除基体元素干扰,ICP－AES法直接测定地质样品中15个微量稀土元素,方法的检出限为0．01－1．1μg.g^-1,精密度（RSD,n=8)为1．3％－5．6％,方法操作简便,快速,经对国家一级标准物质分析,结果与推荐值一致。     

Multi-objective Optimization in the Milling of Titanium Alloys Using the MQL Technique

The process for face milling of (α β) titaniwn alloy while using minimum quarttity librication (MQL) as the cooling technique was optimized by using of the Taguehi method to improve characteristics. The cutting speed, feed rate, and depth of cut were optimized with consideration of multiple performance characteristics including tool life, volume removed and surface roughness. The experimental results show that the nudtiple performance characteristics can be simultaneously improved through this approach, and the feed rate is the most influential cutting parameter in the face milling of titanium alloys.     

Topology optimization of thermoelastic structures using the guide-weight method

The guide-weight method is introduced to solve the topology optimization problems of thermoelastic structures in this paper.First,the solid isotropic microstructure with penalization(SIMP)with different penalty factors is selected as a material interpolation model for the thermal and mechanical fields.The general criteria of the guide-weight method is then presented.Two types of iteration formulas of the guide-weight method are applied to the topology optimization of thermoelastic structures,one of which is to minimize the mean compliance of the structure with material constraint,whereas the other one is to minimize the total weight with displacement constraint.For each type of problem,sensitivity analysis is conducted based on SIMP model.Finally,four classical 2-dimensional numerical examples and a 3-dimensional numerical example considering the thermal field are selected to perform calculation.The factors that affect the optimal topology are discussed,and the performance of the guide-weight method is tested.The results show that the guide-weight method has the advantages of simple iterative formula,fast convergence and relatively clear topology result.     

Synthesis of the CulnSe2 thin film for solar cells using the electrodeposition technique and Taguchi method

The Taguchi method was used to obtain the optimum electrodeposition parameters for the synthesis of the CuInSe2 thinfilm for solar cells.The parameters consist of annealing temperature,current density,CuCl2 concentration,FeCl3 concentration,H2SeO3 concentration,TEA amount,pH value,and deposition time.The experiments were carried out according to an L18(2137) table.An X-ray diffractometer (XRD) and a scanning electron microscope (SEM) were respectively used to analyze the phases and observe the microstructure and the grain size of the CuInSe2 film before and after annealing treatment.The results showed that the CuInSe2phase was deposited with a preferred plane (112) parallel to the substrate surface.The optimum parameters are as follows:currentdensity,7 mA/cm2;CuCl2 concentration,10 raM;FeCl3 concentration,50 raM;H2SeO3 concentration,15 mM;TEA amount,0 mL;pH value,1.65;deposition time,10 min;and annealing temperature,500℃.     

Enhancing the leaching effect of an ion-absorbed rare earth ore by ameliorating the seepage effect with sodium dodecyl sulfate surfactant

Ameliorating the problem of low leaching efficiency, long leaching period, and high agent consumption should be studied to efficiently exploit ion-absorbed rare earth ore resources. In this study, the surfactant sodium dodecyl sulfate (SDS) is used to enhance the leaching effect of an ion-absorbed rare earth ore by ameliorating the seepage effect for the first time. The effects of surfactant concentration, leaching agent dosage, solution flow velocity, and solution pH on the leaching rate were explored, and the mechanism of SDS was discussed. Under the optimum conditions, the addition of a small amount of SDS (mass fraction 0.04%) can increase the leaching rate by about 5%, shorten the leaching period, and reduce the consumption of the leaching agent. SDS significantly ameliorates the seepage effect of the ore body by reducing the surface tension of the leaching agent and ameliorating the wettability of the mineral surface. This effect is the main factor that improves the leaching efficiency. DFT (density functional theory) calculation results show that SDS can react with rare earth ions, which reduces the adsorption strength on clay mineral surfaces. Hence, rare earth ions are easily exchanged by ammonium ions, and mass transfer is enhanced.     

一类超越方程稳定性分析的螺线法

借助螺线的特性对方程λp+c=d(1+λT)-n-1e-αλT的稳定性随T变化而改变的情况作了完整地分析讨论,发现了诸如多次开关现象等稳定性的不同表现.同时把所得的结果与文献[4]对λ+c=d(1+λT)-n-1e-αλT和文献[3]对P(λ)+Q(λ)e-λT=0的研究结果作了全面的比较,纠正了文献[4]中一些错误的说法.进一步拓宽了螺线法研究稳定性的范围,将其推广到形如f(λ)+c=d(1+λT)-n-1e-αλT的一类特征方程.     

Hydrothermal activities and seawater acidification in the Late Devonian F-F transition:Evidence from geochemistry of rare earth elements

Rare-earth elements(REE) in limestones were measured by ICP-MS from the Yangdi section across the Frasnian-Famennian(F-F) transition in Guilin,Guangxi of South China.The averageΣREE contents of measured samples are 33.32 ppm.The average LREE/HREE ratio is 6.35.Data show LREE-enriched REE distribution pattern in the Yangdi section.Most of samples are characterized by positive Eu anomaly with average of 1.13,and there are two maxima of Eu anomaly just below the F-F boundary.Almost all analytical samples show ...     

Synthesis of the CuInSe2 thin film for solar cells using the electrodeposition technique and Taguchi method

The Taguchi method was used to obtain the optimum electrodeposition parameters for the synthesis of the CuInSe2 thin film for solar cells. The parameters consist of annealing temperature,current density,CuCl2 concentration,FeCl3 concentration,H2SeO3 concentration,TEA amount,pH value,and deposition time. The experiments were carried out according to an L18(2137) table. An X-ray diffractometer(XRD) and a scanning electron microscope(SEM) were respectively used to analyze the phases and observe the microstruct...     

Geochemistry of rare earth elements in groundwater from deep seated limestone aquifer in Renlou Coal Mine, Anhui Province, China

Rare earth element (REE) concentrations were measured by ICP-MS for groundwater collected from deep seated Taiyuan Fm limestone aquifer (from-400 to-530 m) in Renlou Coal Mine,northern Anhui Province,China.It can be concluded that the groundwater is warm (34.0-37.2 °C) Cl-Ca,Na type water with circum-neutral pH (7.35-8.28) and high total dissolved solids (TDS,1 746-2 849 mg/L).The groundwater exhibits heavy REEs enrichment relative to light REEs compared with Post Archean Average Shale (PAAS),as well as the...     

Optimum blending of iron ore from Choghart stockpiles by using goal programming

Iron and steel industry is an important sector of Iran’s economy. Choghart iron ore mine is an important iron ore producer of Iran steel industry. Phosphorous contained in the iron ore concentrates of Choghart mine has a detrimental effect on the steel making process, whereby this causes cracks to form in the refractory lining of blast furnaces. In the past, about 1.43 Mt of low-grade and 4.53 Mt of high-phosphorous materials had been transported to low grade and high phosphorous stockpiles, respectively, for future beneficiation. As a result of the progressive depletion of high-grade ore and establishment of beneficiation plant in Choghart, exploitation of these two stockpiles in this mine became an important issue. In this work, a linear goal programming (GP) model was developed in order to determine the optimum iron ore blend in terms of quality from low grade and high phosphorous stockpiles of Choghart mine. The model was solved by the SOLVER V.9 program. Results show that feeding with acceptable quality (w(Fe)≥50% and w(P)≤1.2%, mass fraction) materials can be blended from stockpiles that satisfy the needs of the Choghart processing line.     

球磨机工作参数的离散元法分析与改进

引入离散单元法(Discrete Element Method)建立球磨机的介质动力学仿真模型,研究各种工作参数对球磨机生产效能的影响.DEM模型的运动仿真直观地给出了主要工作参数对介质运动形态的影响;通过对比仿真功率值与实验测量功率值,该模型得到了初步的有效性验证,同时给出了磨机功率随其转速变化的情况.利用该仿真模型对磨机结构进行对比可知,不同的提升条轮廓形状能使球磨机产生不同的能量利用率与磨损率效果.这些均显示了DEM仿真模型在分析和改进球磨机工作参数方面的能力.     

Formability improvement and blank shape definition for deep drawing of cylindrical cup with complex curve profile from SPCC sheets using FEM简

In the current work, to predict and improve the formability of deep drawing process for steel plate cold rolled commercial grade （SPCC） sheets, three parameters including the blanking force, the die and punch comer radius were considered. The experimental plan according to Taguchi＇s orthogonal array was coupled with the finite element method （FEM） simulations. Firstly, the data from the test of stress-strain and forming limit curves were used as input into ABAQUS/Explicit finite element code to predict the failure occurrence of deep drawing process. The three parameters were then validated to establish their effects on the press formability. The optimum case found via simulation was finally confirmed through an experiment. In order to obtain the complex curve profile of cup shape after deep drawing, the anisotropic behavior of earring phenomenon was modeled and implemented into FEM. After such phenomenon was correctly predicted, an error metric compared with design curve was then measured.     

Extraction of valuable metals from low-grade nickeliferous laterite ore by reduction roasting-ammonia leaching method

Nickel and cobalt were extracted from low-grade nickeliferous laterite ore using a reduction roasting-ammonia leaching method. The reduction roasting-ammonia leaching experimental tests were chiefly introduced, by which fine coal was used as a reductant. The results show that the optimum process conditions are confirmed as follows: in reduction roasting process, the mass fraction of reductant in the ore is 10%, roasting time is 120 min, roasting temperature is 1 023–1 073 K; in ammonia leaching process, the liquid-to-solid ratio is 4:1(mL/g), leaching temperature is 313 K, leaching time is 120 min, and concentration ratio of NH₃ to CO₂ is 90 g/L:60 g/L. Under the optimum conditions, leaching efficiencies of nickel and cobalt are 86.25% and 60.84%, respectively. Therefore, nickel and cobalt can be effectively reclaimed, and the leaching agent can be also recycled at room temperature and normal pressure.     

人工补偿逆方法测定L-苯丙氨酸吸附等温线

为了寻求快速、准确和高效的吸附等温线测定方法应用于色谱技术规模化精细分离氨基酸类物质的有效成分过程中，采用人工补偿逆方法进行L-苯丙氨酸的吸附等温线测定。与前沿分析法测定进行比较结果表明：二者结论基本相符。人工补偿逆方法减少了试验数量和目标样品使用量，缩短了试验时间，节约了成本，可以作为氨基酸类产品测定吸附等温线的一种精确、高效方法。     

响应面法优化啤酒污染乳酸菌的培养条件

利用响应面法对一株啤酒污染植物乳杆菌(Lactobacillus plantarum XLL 0095)的富集培养条件进行优化。采用MRS液体培养基培养,探索其24h内富集增菌的最优条件。生长因子、摇床转速和初始pH的单因素试验结果显示,这3个因素对乳酸菌的富集起显著作用。采用Box-Behnken试验设计和响应面分析确定了污染菌富集的最佳条件:摇床转速为153r/min,初始pH为7.57,生长因子添加量为11.8%(体积比)。在此条件下,污染菌24hOD600数值最大,为2.215,比优化前(0.786)增加182%。     

正交分析法优化裂褶菌多糖的微波辅助提取工艺

采用响应曲面法优选和探讨微波提取裂褶菌多糖的最优工艺。在单因素试验的基础上采用SAS 8.2软件设计试验,用响应面分析优化提取时间、料液比、提取温度、微波强度各因素及其相互作用的最佳组合。结果表明,裂褶菌多糖的最优提取工艺条件提取时间为20 min,料液比为1∶28.5,提取温度为51℃,微波强度为548 W,此条件下,多糖实际提取率为1.765%。与其他方法比较,微波提取方法时间短,得率高,是裂褶菌多糖提取的一种优选方法。