利用曲面反应法研究底水油藏水平井含水率变化规律

为揭示底水油藏水平井含水率变化规律,有效降低底水锥进对油藏开发的影响,在建立底水油藏数值模型基础上,运用Box-Behnken实验设计法,对水平井见水特征参数b的6个影响因素(水平井无因次位置、油水黏度比、水平段与主渗透率方向的夹角、垂向与水平渗透率比值、水平段长度、油藏厚度)进行了详细研究。实验后期通过运用曲面反应法得出各影响因素对水平井含水变化的影响顺序和影响交互性。该研究成果对底水油藏的水平井开发具有理论及现场指导意义。     

微晶马铃薯淀粉乙酰化工艺参数优化

为改善马铃薯淀粉性能,拓宽其应用领域,对马铃薯淀粉进行微晶化和乙酰化复合改性。本试验以马铃薯淀粉为原料,盐酸为酸解剂,醋酸酐为乙酰化试剂,氢氧化钠为催化剂,采用响应面法对马铃薯微晶淀粉的乙酰化工艺参数进行了优化。考察了反应温度、反应时间、pH以及醋酸酐用量对乙酰化微晶马铃薯淀粉取代度的影响。用红外光谱对乙酰化微晶马铃薯淀粉进行表征。制备乙酰化微晶马铃薯淀粉的最佳工艺条件为:反应温度30℃,反应时间90 min,pH 8.5,醋酸酐用量17%(醋酸酐用量为占干微晶淀粉质量分数)。     

利用Box-Behnken法优化黑木耳苹果醋的酒精发酵工艺

优化以浓缩苹果汁和黑木耳菌丝体为原料酿制黑木耳苹果醋过程中酒精发酵阶段的工艺条件。采用单因素试验,研究了黑木耳苹果醋酒精发酵过程中初始糖度、发酵温度、pH值和酵母菌接种量4个因素对酒精度的影响,在此基础上利用Box-Behnken法研究确定4个因素共同作用下的最佳工艺参数。研究表明,最佳工艺条件为初始糖度14.5°Bx,发酵温度28℃,pH值5.0,接种量6%,发酵时间7 d,此时发酵液中的酒精度可达到6.63%vol。     

Optimization of total alkannin yields of Alkanna tinctoria by using sub- and supercritical carbon dioxide extraction

The effects of supercritical carbondioxide extraction was investigated to compare previously validated extraction methods on total alkannin yield with Alkanna tinctoria collected form Antalya, Turkey. A two-step process was used; extraction of alkannin derivatives with supercritical CO₂ followed by alkaline hydrolysis of alkannin derivatives. A Box-Behnken exprerimental design was used to evaluate the effect of three variables, pressure (50-350 bar), temperature (30-80 °C) and CO₂ flow (5-20 g min⁻¹) at 1:30 ratio of alkanna root:CO₂ amount. Response surface analysis revealed that the data were adequately fitted to a second-order polynomial model with R² 0.9665 and the most effective variable was pressure (P ≤ 0.05). Optimum conditions were determined as 80 °C, 175 bar, 5 g min⁻¹ CO₂ flow yielding the highest total alkannins (1.47%) which was higher than conventional hexane extraction (1.24%) providing a solvent-free alternative for industrial production.     

Formulation development and optimization of alpha ketoglutarate nanoparticles for cyanide poisoning

The purpose of this research work was to formulate and evaluate alpha ketoglutarate nanoparticles as dry powder inhaler for treatment of cyanide poisoning. Non-polymeric particles were prepared by nano-precipitation technique using various stabilizers. Selection of co-solvent and stabilizer was a key to produce stabilized particles. A combination of lutrol F68 and PVA as a crystal growth inhibitor seems to be best in achieving minimum particle size of 110.2 nm. On the basis of preliminary trials a Box-Behnken statistical design was employed to study the effect of independent variables, drug concentration (X₁), stirring speed (X₂), stirring time (X₃), PVA concentration (X₄), poloxomer concentration (X₅) and volume of co-solvent (X₆) on average particle size. Particle size varied from 110 to 875 nm depending upon the significant terms. Optimized formulation was predicted at drug concentration (50 μg/ml), stirring speed (640 rpm), stirring time (1 min), PVA concentration (1%), poloxomer concentration (1.69%) and volume of co-solvent (30 ml) with 104.6% experimental validity. The nanosized particles were further characterized by X-ray diffraction (XRD), Differential Scanning Calorimetry (DSC), Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared Spectroscopy (FT-IR) analysis. The results of particle characterization indicate that there was no physical disparity when compared with the commercial α-KG sample.     

Numerical simulation of effects of operating conditions on the molecular weight of polypropylene using a response surface method

A L4635 Box-Behnken design was used for developing a model to predict and optimize the molecular weight(Mw)of polypropylene(PP);a second-order polynomial regression equation was derived to predict responses.The significance of variables and their interactions were tested by means of the ANOVA with 95% confidence limits;the standardized effects were investigated by Pareto chart,the optimum values of the selected variables were obtained by analyzing the response surface contour plots.The optimized Mwvalue of 1.217×105 g/mol was very close to the industrial value((1.22±0.004)×105 g/mol)at the optimum values.     

KMnO4 pre-treatment of linen

Currently, for the textile industry, the economical considerations are of great importance. The concept of eco-friendliness is of greater concern for textile processing, as the chemical wet treatment has a major role in effluent generation. Thus, research activities these days are oriented towards the alternative ways of chemical processing. Potassium permanganate, a strong oxidising agent can be employed for the pre-treatment of grey linen. The experimental investigation reveals that the KMnO₄ concentration, temperature and treatment time have noticeable impact on quality of bleached linen. The results are evaluated in terms of whiteness index and strength of fabric and the treatment factors are optimised using design of experiment. The results demonstrate that the KMnO₄ can be employed for simultaneous desizing and bleaching of grey linen.     

超声波协同微波提取牛蒡籽油的工艺研究

优化超声波协同微波提取牛蒡籽油的工艺参数,并利用扫描电镜从微观角度解释了最佳得率的获得,最后和其他提取方法进行对比。结果表明：超声波协同微波提取牛蒡籽油最佳工艺参数为提取时间213s、微波功率303W、液料比10.1:1(ml/g),此时牛蒡籽油得率为19.334%;超声波的空化效应、机械效应和微波的热效应造成了生物细胞壁及整个生物体的断裂与破碎,这解释了超声波协同微波提取牛蒡籽油效率高的原因;与其他提取方法相比,超声波协同微波提取时间短、得率高。     

船舱隔壁螺旋槽旋转密封装置密封性能优化

为研究螺旋槽旋转密封装置用于船舱隔壁密封的密封性能,同时获取螺旋槽结构的最优取值范围,对螺旋槽各参数对泄漏量影响规律进行理论分析;选取泄漏量的显著性影响因素,采用Box-Behnken优化方法设计密封装置泄漏量试验,得到多型样机泄漏量测试结果;建立泄漏量和各影响因素间的数学模型,获得不同影响因素对泄漏量的二阶交互作用响应面,分析不同影响因素间交互影响规律。结果表明：螺旋槽密封装置泄漏量随槽数、螺旋角和槽深比的增大均先增大后减小,随槽台比和槽坝比的增大则逐渐增大;建立的数学模型计算结果和试验数据相关性较强,表明该模型可用于准确预测船舱隔壁螺旋槽旋转密封装置泄漏量。     

微波-酶法制备RS3型玉米抗性淀粉工艺参数优化研究

运用响应面法,对微波-酶法制备RS3型玉米抗性淀粉的工艺参数进行优化。α-淀粉酶酶解的优化工艺参数为:液料比4:1,酶解温度85℃,酶解时间10min,酶浓度1．68U/g淀粉:微波糊化的优化工艺参数为:功率1．26kW,加热温度92℃,加热时间1min:普鲁兰酶脱支优化工艺参数为:酶浓度4．13 NPUN/g淀粉,酶解温度53．31℃,酶解时间3．26h。按以上工艺参数制备的抗性淀粉得率为13．45%。