STUDY ON GREY FORECASTING MODEL OF COPPER EXTRACTION RATE WITH BIOLEACHING OF PRIMARY SULFIDE ORE

A model GM （grey model） （1,1） for forecasting the rate of copper extraction during the bioleaching of primary sulphide ore was established on the basis of the mathematical theory and the modeling process of grey system theory. It was used for forecasting the rate of copper extraction from the primary sulfide ore during a laboratory microbial column leaching experiment. The precision of the forecasted results were examined and modified via ＂posterior variance examination＂. The results show that the forecasted values coincide with the experimental values. GM （1,1） model has high forecast accuracy; and it is suitable for simulation control and prediction analysis of the original data series of the processes that have grey characteristics, such as mining, metallurgical and mineral processing, etc. The leaching rate of such copper sulphide ore is low. The grey forecasting result indicates that the rate of copper extraction is approximately 20% even after leaching for six months.

A rate-based method for dynamic analysis and optimal design of reactive extraction: n-Hexyl acetate esterification as an example

The dynamic analysis and optimal design of reactive extraction are challenging due to high nonlinearity of model equations and tough decision of judging criteria. In this work, a dynamic rate-based method is developed on g PROMS platform to get easy access to the solutions of reactive extraction with phase splitting. Based on rigorous criteria, dynamic analysis from initial state to final equilibrium(e.g., evolution of phase composition, mass transfer rate and reaction rate) and optimal design of operating conditions(e.g., extractant dosage and feed molar ratio) are achieved. To illustrate the method, the esterification of n-hexyl acetate is taken as an example. The approach proves to be reliable in the analysis and optimization of the exemplified system, which provides instructive reference for further process design and simulation of reactive extraction.

Line-of-sight rates extraction of roll-pitch seeker under anti-infrared decoy state

In this paper,the method of extracting guidance information such as the line-of-sight(LOS)rates under the anti-infrared decoy state for the roll-pitch seeker is researched.Coordinate systems which are used to describe the angles transform are defined.The LOS angles reconstruction model of the roll-pitch seeker in inertial space is established.A Kalman filter model for extracting LOS rates of the roll-pitch seeker is proposed.In this model,the target performs constant acceleration(CA)model maneuvers.The error model of LOS rates extraction under infrared decoy state is established.Several existing methods of extracting LOS rates under anti-infrared decoy state are listed in this paper.Different from the existing methods,a novel method that uses extrapolated values of target accelerations as filter measurements is proposed to solve the guidance information extraction problem under the anti-infrared decoy state.Numerical simulations are conducted to verify the effectiveness of the proposed method under different target maneuvering models such as the CA model,the CA extended model and the singer model.The simulation results show that the proposed method of extracting guidance information such as LOS rates for the rollpitch seeker under the anti-infrared decoy state is effective.

5α-还原酶植物抑制剂的筛选及其对小鼠毛发生长的影响

本研究以水、无水乙醇、丙酮、石油醚作为溶剂提取人参、苦参、川芎等17种药用植物,采用Ⅰ型5α-还原酶(5αR1)抑制剂体外筛选实验,探究不同提取物对5αR1活性的影响。考察5αR1抑制作用较强的川芎、乌斯玛草和女贞子的水提物对丙酸睾酮诱导的雄激素脱毛小鼠的育发促生效果.体外实验结果显示女贞子、川芎、乌斯玛草、红药子、人参、制何首乌、枸杞、苦丁、迷迭香等植物提取物的作用较显著,在5 mg/mL浓度下,对5αR1的抑制率大于50%,其中乌斯玛草石油醚提取物的抑制率最高,为(78.48±3.35)%.小鼠活体育发实验结果显示川芎与乌斯玛草水提物对雄激素脱毛小鼠具有明显的育发促生作用。

阀门开度对光伏水泵提水系统影响研究

针对不同辐照度下光伏水泵提水系统管路特性固定导致较多太阳能浪费的问题,探究不同辐照度与阀门开度下光伏水泵流量与扬程变化规律,根据光伏供能与提水管路需能供需平衡理论分析,建立辐照度、管道流量、阀门开度的数学关系式,对其求导得出最大流量阀门开度模型,并试验验证。结果表明:随着辐照度增大,光伏水泵的流量、扬程同时增大,利用建立的最大流量阀门开度模型,对不同辐照度下提水高度为14 m的光伏提水系统的阀门开度进行调节,以瞬时流量最大为目标,相比于阀门全开,调节后提水量增幅为79.66%,表明通过调整阀门开度可有效提高光伏水泵提水系统的提水量。

薇甘菊提取物对稻瘟病菌的抑菌活性

【目的】以入侵物种薇甘菊Mikania micrantha为材料,探究其不同提取物及组分对稻瘟病菌Magnaporthe oxyzae的抑菌活性。【方法】以稻瘟病菌为供试病原菌,采用生长速率法对采自云南德宏的薇甘菊提取物进行室内抑菌活性测定,并通过柱层析对提取物的抑菌活性组分进行追踪。【结果】在初筛质量浓度为1 mg/mL时,薇甘菊乙酸乙酯萃取物对稻瘟病菌有较好的抑菌活性,抑菌率为49.84%。对薇甘菊乙酸乙酯萃取物的14个柱层析组分进行抑菌活性追踪,组分Fr_(5)、Fr_(6)、Fr_(12)、Fr_(13)抑菌效果显著,在接种后第9天的EC_(50)分别为1.691、2.134、0.865、0.818 mg/mL;4个组分均使菌丝质量减轻,MDA含量升高,菌丝形态畸变。【结论】本研究发现薇甘菊提取物对稻瘟病菌有较好的抑菌效果,为综合开发利用薇甘菊提供了新思路,也为稻瘟病菌的绿色防控提供了科学依据。

Kinetic Mechanisms for Preparing Silymarin via Microwave-assisted Extraction

The kinetic mechanism for the preparation of silymarin from milk thistle seeds was studied during the microwave-assisted extraction （MAE） process. The results showed that the transfer rate of silymarin from milk thistle seeds increased with the microwave output power and temperature during MAE processing. The apparent extraction rate constant k （s-1） was 1.2028×10-2 , 1.2248×10-2 , and 1.2485×10-2 , and diffusion coefficient D （m2·s-1 ） was 4.21×10-10, 4.29×10-10 , and 4.37×10-10 at the microwave temperatures of 383, 393, and 403 K, respectively, in the silymarin MAE process. With the help of scanning electron microscopy （SEM）, the microstructures of the samples extracted by MAE were observed. The results revealed that the increased efficiency and rate of MAE of silymarin could be attributed mainly to the subsequent cell change resulting from superheating effects during MAE.

Optimization of Enzyme-assisted Extraction Technology for Tartary Buckwheat Shell Procyanidins with Response Surface Methodology

This study was conducted to investigate the effects of cellulase dosage, enzymolysis time, pH and enzymolysis temperature on procyanidin extraction rate by single factor experiment, with tartary buckwheat shell as an experimental material.Main process parameters were optimized to obtain a regression model by response surface methodology. The results of variance analysis indicated that the regression model reflected the relationship between buckwheat shell procyanidin extraction rate with enzyme dosage, enzymolysis time, pH and enzymolysis temperature; and the optimal process parameters were enzyme dosage of 6.5 mg/g, enzymolysis time of 1.5 h, pH at 4.7 and enzymolysis temperature at 46 ℃. Three parallel experiments were conducted under these process parameters. In practice, the highest procyanidin extraction rate was 6.78 g/100 g. The relative error between the predicted value of regression model and the actual value was 1.3%. The regression equation fitted the real situation better.

Extraction Technology of Eight Botanical Pesticides and Their Antifungal Activities on Fungus

[ Objective] The optimum extraction technology of antifungal ingredients from eight medicinal plants such as coptis root and clove, etc. and their antifungal effects on two species of plant pathogens were studied. [ Method] The effective ingredients of medicinal plants were extracted by water, ethanol and acetone. The minimum inhibitory concentration （MIC） and antifungal rate of extracts from medicinal plants were determined using plate diluting method. [Resets] The optimum medicinal plants and the extraction methods inhibited two plant pathogens were as follows： clove extracted by ethanol and acetone, and cinnamon extracted by ethanol could be adopted to inhibit Fusarium oxysporum Schl., MIC at that mo- ment reached 4 mg/ml. Clove extracted by ethanol and acetone, and cinnamon extracted by ethanol could be adopted to inhibit the pathogen of Cistanche deserticola, MIC at that moment reached 4 mg/ml. [ Conclusion] The antifungal effects of ethanol and acetone extracts on tested patho- gens were obviously superior than that of aqueous extracts.

Process Optimization of Ultrasonic Extraction of Puerarin Based on Support Vector Machine

In ultrasonic extraction technology, optimization of technical parameters often considers extraction medium only, without including ultrasonic parameters. This paper focuses on controlling the ultrasonic extraction process of puerarin, investigating the influence of ultrasonic parameters on extraction rate, and empirically analyzing the main components of Pueraria, i.e., isoflavone compounds. A method is presented combining orthogonal experi- mental design with a support vector machine and a predictive model is established for optimization of technical parameters. From the analysis with the predictive model, appropriate process parameters are achieved for higher extraction rate. With these parameters in the ultrasonic extraction of puerarin, the experimental result is satisfactory. This method is of significance to the study of extracfing root-stock plant medicines.

Studies on Extraction Process of Polysaccharides from Saccharomyces cerevisiae

In this study, with Saccharomyces cerevisiae as the experimental material, microwave-assisted technology, phenol-sulfuric acid method and UV spectro- photometry were employed to investigate the extraction rate of polysaccharides. Solid-liquid ratio, microwave power and microwave processing time were adopted as single factors to optimize the extraction conditions. Subsequently, orthogonal experiment was performed to investigate the optimal extraction process of polysaccha- rides from S. cerevisiae. The optimal extraction conditions were： solid-liquid ratio 1 ： 20, microwave power 250 W, microwave processing time 3 min, under which the extraction rate of polysaccharides reached 4.98%. Compared with conventional hot water extraction method, microwave-assisted extraction technology exhibited shorter extraction time, higher efficiency, and could save more energy.

Pressurized Synchronous Extraction of Volatile Oils, Total Flavonoids and Tannic Acid from Artemisia argyi

[Objectives] This study aimed to optimize the conditions for pressurized synchronous extraction of volatile oils, total flavonoids and tannic acid from Artemisia argyi .[Methods] Single factor experiments and orthogonal experiments were conducted.[Results] Pressurization had a significant effect on the extraction rate of chemical constituents of A. argyi . The optimal conditions for pressurized synchronous extraction of volatile oils, total flavonoids and tannic acid from A. argyi were as follows: solvent concentration of 70%, solid to liquid ratio of 1∶ 30 (g/mL), extraction pressure of 0.9 MPa, extraction time of 40 min and extraction temperature of 90 ℃. Under the optimal extraction conditions, the yields of volatile oils, total flavonoids and tannic acid were 0.852%, 4.66% and 6.79%, respectively.[Conclusions] Compared with other extraction methods, the pressurized assistant solvent extraction method can achieve the synchronous extraction of volatile oils, total flavonoids and tannic acid from A. argyi . The process is stable, short in extraction time, high in solvent utilization rate and ideal in extraction effect of the three components from A. argyi .

纤维素酶辅助提取马齿苋总黄酮工艺优化及抑菌分析研究

用纤维素酶处理马齿苋,利用响应面设计,从纤维素酶添加量、酶解时间、酶解温度、酶解pH值四个因素优化纤维素酶处理后的黄酮提取率。对马齿苋提取物粗粉中的总黄酮进行抑菌试验。结果表明:脱脂后的马齿苋经测定黄酮类化合物含量为5.32%。最佳工艺条件为酶解温度50℃,酶的添加量0.6%,酶解时间1.8 h,酶解的pH值4.5,所得黄酮提取率6.09%,与未经酶处理相比,提取率提高1.14倍。对验证试验的黄酮粗粉进行抑菌试验,表明对金黄色葡萄球菌和大肠杆菌均有抑制作用,其中对大肠杆菌的抑菌效果较好。马齿苋经过纤维素酶酶解后,黄酮分子从细胞内溶出,提高马齿苋黄酮的提取率,提取的黄酮粗粉有抑菌活性,本研究为马齿苋黄酮的分离纯化、功能性研究提供支持。

A Semi-automatic Method Based on Statistic for Mandarin Semantic Structures Extraction in Specific Domains

This paper proposed a new method of semi-automatic extraction for semantic structures from unlabelled corpora in specific domains. The approach is statistical in nature. The extracted structures can be used for shallow parsing and semantic labeling. By iteratively extracting new words and clustering words, we get an inital semantic lexicon that groups words of the same semantic meaning together as a class. After that, a bootstrapping algorithm is adopted to extract semantic structures. Then the semantic structures are used to extract new

4种提取方法对对虾肌原纤维蛋白提取率、空间结构和热稳定性的影响

【目的】获取提取率高且结构完整的凡纳滨对虾(Litopenaeus vannamei)肌原纤维蛋白。【方法】通过0.5 mol/L KCl、53 kHz超声辅助0.5 mol/L KCl、53 kHz超声辅助质量分数5%十二烷基硫酸钠(SDS)和RIPA裂解液这4种提取方法提取对虾肌原纤维蛋白,以肌原纤维蛋白提取率和结构完整性为评价指标,采用光谱学和凝胶电泳生化,评价四种提取方法对对虾肌原纤维蛋白提取率、空间结构和热稳定性的影响。【结果】53 kHz超声辅助0.5 mol/L KCl、0.5 mol/L KCl、53 kHz超声辅助5%SDS和RIPA裂解液4种方法所得提取率分别为(87.99±3.08)%、(53.76±3.90)%、(75.59±0.95)%和(95.46±4.49)%。53 kHz超声辅助0.5 mol/L KCl提取的蛋白中肌钙蛋白和原肌球蛋白蛋白丰度较高,0.5 mol/L KCl和53 kHz超声辅助质量分数5%SDS提取的肌球蛋白重链和肌动蛋白蛋白丰度较高;相较于0.5 mol/L KCl,超声辅助提取可最大限度保持肌原纤维蛋白天然结构,α-螺旋结构保留完好;0.5 mol/L KCl提取可较好维持肌原纤维蛋白的酰胺Ⅰ带结构。RIPA裂解液提取对肌原纤维蛋白二级结构有明显破坏,热稳定性仅为原蛋白的(60.63±4.46)%。【结论】综合提取率、空间结构和热稳定性结果,采用53 kHz超声辅助5%SDS提取可获得质量最佳的凡纳滨对虾肌原纤维。本研究可为后续深入解析冷藏对虾品质劣变和开发高效控制技术提供高质量的肌原纤维蛋白。

Rheology study of supercritically extracted tea-oil

The rheological analysis on dynamic shear rate-viscosity relationship of tea-oil extracted from tea-oil tree seeds by supercritical extraction method was carried out at gradient temperatures and constant shear rate,respectively.The results show that at 20,40,60 and 80 ℃,once the shear rate increases gradually,the torque enlarges correspondingly,while the viscosity shows little difference.However,at the constant shear rate,the rising temperature results in a steady downtrend on tea-oil viscosity.This results reveal that tea-oil viscosity is not closely correlated with shear rate at constant temperature,yet negatively correlated with temperature at constant shear rate.

岩巷综掘面抽尘参数影响粉尘污染扩散规律研究

抽尘系统是岩巷综掘面长压短抽通风方式中控除粉尘污染的重要组成部分,而确定适宜的抽尘参数是实现有效除尘的关键。利用Solidworks软件对某矿632岩巷综掘面进行了物理建模,并进行了ICEM-CFD网格划分,通过网格无关性检验确认了后续所用的网格模型,运用FLUENT计算流体力学软件对不同抽尘位置Dn(n分别为0、1/4、1/2、3/4、1)与抽风量(300~350 m^(3)/min)影响粉尘污染扩散状况进行了数值模拟,并通过仿真试验验证了数值模拟结果的准确性。结果表明:抽尘位置为D0、D1/4、D1/2、D3/4时,巷道内风流整体均处于较为紊乱的状态,粉尘污染经风流运载最终均扩散至整个巷道;抽尘位置为D1时,在抽风与压风协同作用下,距迎头4.6~6 m范围内形成了风向指向迎头、流动均匀且覆盖巷道全断面的有效控尘风幕,粉尘污染被风幕控制在掘进机司机与迎头之间的封闭空间内。抽风量在330 m^(3)/min及以上时,在司机处均形成了有效控尘风幕。为了在有效控尘的前提下尽可能降低能耗,最优抽风量选取最小值330 m^(3)/min。

多指标响应面优化枸杞提取工艺研究

枸杞中含有丰富的枸杞多糖和枸杞黄酮,均具有较高的药用价值。选取提取方法、提取时间、料液比、提取次数、提取温度、浸泡时间进行单因素试验,根据单因素结果选取3个影响较大的因素,结合响应面法中的Box-Behnken试验设计对枸杞总多糖和总黄酮的提取工艺进行优化,得到优化提取工艺条件为:加热回流法,浸泡1.0h,提取时间55min,料液比1∶12(g∶m L),提取温度81℃,提取2次。总多糖提取率能够达到45.36%,总黄酮提取率达到0.29%。该方法提取率高、重复性好,高效环保。为枸杞中总多糖和总黄酮的提取方法提供参考依据。

新疆制种玉米生产机械化技术——去雄

新疆是我国重要的制种玉米种植区,玉米母本的雄穗去除是制种玉米种植的关键环节之一。受种植模式和去雄技术要求的影响,不同地区在去雄方法、机械去雄使用情况上存在不同。人工去雄可以根据雄穗的生长情况,选择性的去除,整个去雄期需要进行5~6次抽雄。机械去雄采用直接抽雄或者先切顶然后抽雄两种方法,抽净率为80%~95%,机械去雄对叶片的损伤较大,机械去雄后需要人工检查并对未去雄玉米母本再次抽雄。为了全面推广应用机械去雄技术,应进一步规范和提高适于机械化作业的种植模式、机械抽雄技术以及去雄机的整机性能。

Box-Behnken响应面法优化葛根异黄酮提取纯化工艺及损伤心肌细胞治疗作用研究

目的:采用Box-Behnken响应面优化葛根异黄酮最佳提取工艺,并研究葛根异黄酮对损伤心肌细胞的治疗作用。方法:在单因素实验的基础上,以料液比、提取时间、溶剂浓度为考察因素,以3'-羟基葛根素、葛根素、3'-甲氧基葛根素、大豆苷的含量为评价指标,采用Box-Behnken响应面法设计实验,以葛根异黄酮总提取率为考察指标,通过分析回归方程模型,优选最佳提取工艺并验证工艺;采用MTT法检测葛根异黄酮对损伤心肌细胞的治疗作用。结果:Box-Behnken响应面法优化得到葛根异黄酮最佳提取工艺为:料液比为30 mg·mL^(-1),提取时间为100 min,乙醇体积分数为73%,葛根异黄酮的总提取率平均值为41.6 mg·g^(-1),与预测值42.08 mg·g^(-1),相对误差0.81%;葛根异黄酮对H 2O_(2)损伤的缺氧复氧模型和Na 2S_(2)O 4损伤的缺血再灌注模型OD值分别为0.7436±0.0292和0.7457±0.0094,细胞存活率分别为81.32%和73.41%。结论:优选葛根抗氧化活性异黄酮最佳工艺稳定,预测模型效果良好,且葛根异黄酮对心肌缺血有良好的治疗作用。