磁场对重介旋流器密度场影响的实验研究

利用ANSYS电磁场分析软件对通电线圈在重介旋流器内部产生的磁场分布进行模拟研究,并在实验室进行带煤分选实验;通过软件分析获得磁场在旋流器内部的磁场力分布图,进而来确定线圈参数和预测密度场变化趋势;通过磁场作用下带煤分选实验获得产物的浮沉表并绘制分配率曲线图,得出δp值及可能偏差E值变化范围,来说明磁场的存在确实会对重介旋流器的密度场分布产生影响。

重液分选茶卡北山水系沉积物及其对伟晶岩型锂矿床探矿的指示意义

伟晶岩型锂矿是最重要的锂金属来源之一,由于在时间、空间和构造背景方面存在显著的不均一性,该型矿床目前尚无有效的探矿方法。在迁移搬运过程中,水系沉积物保留了蚀源区矿物信息,利用其元素和矿物组成,可在一定程度上还原沉积物物源区的矿物组成特征。分析水系沉积物中含锂重矿物的亏损与富集以及粒径的变化,是伟晶岩型锂矿探矿的有效方法之一。文章以茶卡北山流域的水系沉积物为研究对象,经逐级精细化地重液分选,实现了重、轻质矿物的有效分选。结果表明,河流过程可以对水系沉积物中的锂含量产生较大的影响,无支流时的搬运距离越远,水系沉积物中的锂含量越少,支流混合可以对水系沉积物中的锂含量产生正相关影响。重液分选方法对水系沉积物含锂矿物产生了有效的富集作用,主要富集锂元素的载体为云母类矿物,锂元素含量较未分选前提高3~14倍,且在分选后产生了明显的矿物组成差异。这种变化规律可用于对含锂伟晶岩矿物的指示与追踪,因此水系沉积物的重液分选法是伟晶岩型锂矿床探矿的重要指示方法。

Isolation of Endophyte and Screening for Antagonistic Bacteria in Solanaceae

[ Objective] The aim of this study was to isolate the endophyte of three solanaceae fruits and vegetables such as tomato, pepper and eggplant, to screen and identify the bacterial wilt antagonistic bacteria. [ Methodl According to the lapping liquid culture method, the endophyte of three plants was isolated by the selective medium and purified by the plate streaking method, so the purified enclophyte was screened by the hyphal pieces confront culture method. Furthermore, the screened antagonistic and endophyteic bacteria was identified and classified through culture characteristics of isolates and morphological features of thallus, Gram stain as well as physiological and biochemical reactions. [ Result] Fifty-three endophytic bacteria, fifty-three endophytic fungi and forty-four endophytic actinomycetes were separated from the endophyte of three plants. The screened fourteen endophytic bacteria with strong antagonistic effect on the bacterial wilt were classified to Bacillus, Escherichia, Klebsiella, Agromonas, Erwinia and Curto Bacterium respectively. Especially, Bacillus was the dominant species, which had the strongest antagonistic effect on the bacterial wilt. [ Conclusion] This study provides an effective way for biological control of the bacterial wilt in solanaceae.

Optimization of reagent dosages for copper flotation using statistical technique

The effects of Z11 and AP407 collectors as well as AF65 and AF70 frothers were evaluated in the rougher flotation circuit of the Sungun copper concentrator plant using 2 4 full factorial design.Response functions were produced for both Cu grade and recovery and optimized within the experimental range.The optimum reagent dosages were found to be 12.01 g/t Z11,11 g/t AP407,3 g/t AF65 and 5 g/t AF70 to attain the maximum Cu grade(8.17%).The reagent dosages of 12 g/t Z11,11 g/t AP407,3 g/t AF65 and 15 g/t AF70 produced the maximum Cu recovery(86.44%).The collector distribution demonstrated that the distribution pattern of(32%,32%,20%,16%)can produce the best recovery(87.75%)in comparison to other examined distribution patterns.

Performance analysis of jig for coal cleaning using 3D response surface methodology

Beneficiation of coal of -4.76 mm + 3 mm size fraction was investigated in a laboratory model Denver jig.Process variables were studied to analyze their effect on the performance of jig in terms of yield and ash content of clean coal. Three-factor three-level Box-Behnken design of experiments with response surface methodology(RSM) was employed to understand the performance behavior of jig. From the study, the bed height was found to be the most significant parameter affecting the yield and ash content of clean coal. It was possible to reduce the ash content from 24.32% in feed to an ash content of 16.55% in clean coal at 2 L/min water flow rate and 10 min jigging time. Influence of operating variables of the jig on responses was presented and discussed in 3D surface plots. The developed model was found to be significant within the range of parameters under investigation with correlation of co-efficient values as 0.99(yield) and 0.98(ash).

Influence of Oscillation Frequency of a Sieve on the Screening Process for a Conical Sieve with Oscillatory Circular Motion

Removal of foreign bodies from seed mixtures, or their calibration for use as planting material, as well as fraction classification of granular materials requires screening surfaces with vibratory motion. This paper presents some aspects on the working process of a sieve, made of perforated sheet and having an outer conical surface with oscillatory circular motion （alternative） on the horizontal. Results are presented for some experimental researches on the movement of material on the sieve, for various kinematical parameters of the sieve （amplitude and oscillation frequency）. A conical sieve, suspended at the upper and lower in three points, was tested for screening of rapeseeds in order to estimate the influence of oscillation frequency on the screening process. Curves were drawn for separation intensity on the sieve generating line, and by regression analysis with normal distribution law were determined the equation coefficients and the correlation with experimental data. Movement of material on the sieve and its working process, in general, was appreciated by means of the peak position of distribution curve depending on the oscillation frequency of the sieve, considering that the normal distribution law correlates very well the data obtained by experiments.

Nutritional Properties of Commercial Flavored Milk

Consumers are becoming increasingly health conscious, and food product choices have expanded. Flavored milk increases milk consumption in children and providing adequate calcium intake as well as associated nutrients. About 40% of the sugar in flavored milk is naturally occurring lactose beverages. The goal of this study was to test the truthfulness of the labeling concerning protein, fat and sugar content of the flavored milk. Moreover, the compliance with the Gulf standard was tested. Ten different brands of flavored milk were used in this study. As per labeled on the package, this study found that： one company did not mention clearly that their products are nonfat milk. We also found that there were variations in the percentage of fat between the ten types of flavored milk. For calcium content, all companies indicated clearly the calcium content except company eight. Concerning laboratory analysis, one company considered as mislabeled since they stated on the package that the percentage of fat 1.1-1.2 and the lab analysis showed it contained 3.1%. All companies were truthful about protein content. Moreover, for calcium, all companies have low calcium content than what has stated on the package except one company.