单纯形重心设计法复配酸乳饮料稳定剂研究

在时果胶、CMC、PGA三种稳定剂单体影响酸乳饮料稳定性单因素实验的基础上,采用{3,2}单纯形重心设计法进行稳定剂的复配.复配的结果显示:当果胶、CMC、PGA添加量分别为0.083%、0.1%、0.14%.总的添加量为0.323%,此时酸乳饮料的离心率降低至2.11%,以此配方生产的产品稳定性较高,符合生产实践的要求.     

基于单纯形-重心设计的菜籽粕生物改良菌株的复配研究

硫甙和中性洗涤纤维是限制菜籽粕饲用的两个重要抗营养因子。发酵法是降低菜籽粕抗营养因子的重要手段。通过初筛、复筛和混料设计,优选了混合菌发酵菌株和接种比例。在初筛中采用菜籽粕鉴定培养基,在复筛中对硫甙降解率、中性洗涤纤维降解率、生长曲线和蛋白酶酶活进行综合评价,在复筛的基础上采用单纯形-重心设计进行菌株配比的优化,拟合出因素与响应值之间的回归方程,得到优化的菌株接种比例为枯草芽孢杆菌B3 46%、纳豆芽孢杆菌N1 30%、酿酒酵母R1 24%,在此条件下进行发酵试验,硫甙、中性洗涤纤维的降解率分别为94.63%、24.17%。     

基于单纯形-重心设计实验红曲色素类脂肪酶抑制剂提取研究

研究表明,某些红曲色素或其衍生物具有显著的脂肪酶抑制活性。该类物质通过抑制消化道内脂肪酶活性,阻止食物中脂肪的水解,达到减少脂肪吸收,预防和改善肥胖症状的目的。以发酵过程中添加氨基酸混合物(L-甲硫氨酸、L-缬氨酸、L-苯丙氨酸、L-色氨酸、L-亮氨酸和L-组氨酸)的红曲发酵产物为提取原料,以脂肪酶抑制率以及色价为考察指标,借助单纯形-重心设计实验方法考察了三种溶剂(水、乙醇和乙腈)的不同组合与比例对原料中色素类脂肪酶抑制剂的提取效果的影响。结果表明,溶剂组合为水/乙醇(1/2∶1/2, v/v)时,提取物的脂肪酶抑制活性最高,同时色价也较高,因此该溶剂体系更适合红曲色素衍生物类脂肪酶抑制剂的提取,为开发抗肥胖红曲产品提供有益依据。     

基于单纯形-重心设计优化气调包装冷鲜猪肉的气体比例

为优化冷鲜猪肉气调包装的气体比例,增强其保鲜效果,以菌落总数、挥发性盐基氮(TVB-N)值、p H和感官品质为指标,基于单纯形-重心设计考察O_2、CO_2和N_2的不同配比对冷鲜猪肉的品质维持作用。通过与托盘包装的对照组比较发现,适宜的气体配比能有效抑制冷鲜猪肉中微生物的生长、减少TVB-N的生成、保持产品的感官品质,且各指标两两之间均存在极显著的相关性(p0.01)。以三种气体各自所占体积百分比为因素,筛选产品贮藏至第8 d和第10 d的菌落总数、TVB-N值及二者加权值为响应值,建立6套回归模型并分别优化得到6组气体配比方案。通过验证确定冷鲜猪肉气调保鲜的最佳气体比例为22%O_2和78%CO_2,在此条件下贮藏至第8 d的菌落总数和TVB-N值分别为5.85 lg(cfu/g)和14.00 mg/100 g,相比对照组可延长产品货架期达5 d。     

从原问题的最优表中读对偶最优解

讨论了在各种情况下从原问题的最优表中得到其对偶最优解的方法并给出证明。     

预聚物对UV胶印油墨性能的影响

使用EB3700,6358H和6353-1三种预聚物,运用单纯形重心设计方法,确定复合预聚物的比例,分别考察了单一预聚物和复合预聚物对UV胶印油墨样品的流动曲线、触变性破解指数、固化速度、光泽度、油墨转移率及实地密度的影响。研究结果表明,含有预聚物6358H的油墨样品具有较高的黏度,其触变性破解指数也较大;含有预聚物6353-1的样张具有较高的光泽度;含有预聚物EB3700的样张实地密度较大,且具有较快的固化速度;将EB3700和6353-1混合制备的油墨样品具有较高的油墨转移率。运用单纯形重心设计方法求得三种预聚物EB3700:6358H:6353-1的最佳复合比例为1.4:1:1。     

试论线性规划在高校图书馆管理中的应用

由于高校图书馆期刊订购经费有限,以及期刊的价格逐年上升,传统的期刊订购方法难以使期刊订购经费的利用达到最佳。为了使期刊订购的方法更科学,本文提出期刊订购的线性规划模型。该方法通过期刊订购过程各种因素的分析,合理确定期刊的效用系数,建立期刊订购的一个线性规划数学模型。并用一个实际例子说明如何建立期刊订购的线性规划模型,对实际例子采用单纯形解法求解,为提高期刊订购的效用提供了一种科学方法。     

线性规划的单纯形解法在编制资源分配计划中的应用

本文就纺织工业中,编制资源分配计划时,引入线性规划数学模型的意义进行了阐述,并对求解线性规划的基本方法——单纯形法,在表上迭代的步骤以实例的形式进行了介绍。     

SPSS在金属结合剂配方试验中的应用

文章对超硬磨具金属结合剂配方采用单纯形格子点设计,利用SPSS软件对实验数据进行非线性回归分析,得到拟合性优良的回归函数模型,并利用excel规划求解工具得到最优化配方,结果表明,SPSS在超硬磨具配方试验中有很好的应用价值。     

Standardization of Mapping Simplex Optimization

Although the mapping process significantly improved the efficiency of simplex optimization, the procedure subsequent to mapping required manual adjustments. An attempt was made to standardize the optimization procedure so as to avoid subjectivity. A selfinstructive computer program of the standardized procedure was written for a hand-held computer. The program was inexpensive and convenient to apply the mapping simplex optimization to problems in product and process development.     

Simultaneous optimization of response variables in protein mixture formulation: constrained simplex method approach

Summary The objective of this study was to test a complex constrained simplex, direct search, sequential method for the optimization of a ternary mixture of protein ingredients used in a formulation for the preparation of a milk drink regularly consumed in institutional nutritional programmes. Three proteins [hydrolysed gelatine (HG), wheat gluten (WG) and soybean protein isolate (SPI)] were mixed according to a simplex‐centroid design, in order to explore the possible synergies between the sensory, nutritional and economic attributes. Mixtures containing different proportions of the three ingredients were submitted to sensory, nutritional and economic evaluations. All responses were modelled using Scheffé's canonical equations. A microinformatics application was developed in order to permit optimization to be computed. The optimum solution obtained by this non‐linear programming was HG = 20%, WG = 27% and SPI = 53%, suggesting that the program is efficient and flexible enough for multiresponse optimization. The optimal point behaviour of the entry variables (HG, WG and SPI) can be monitored with graphs of the trace plot type, in which the proportion of two variables is fixed and the third is allowed to vary in relation to the desired response.     

单纯疱疹病毒胸苷激酶基因联合更昔洛韦治疗肿瘤的机制

单纯疱疹病毒胸苷激酶基因(HSV-TK)与抗病毒药物更昔洛韦(GCV)组成的药物敏感基因疗法在肿瘤基因治疗领域中引人注目,它产生的旁观者效应在一定程度上弥补了基因载体转染率不高的问题,在肿瘤自杀基因疗法中发挥着重要的作用,现对HSV-TK/GCV治疗肿瘤机制及其应用趋势作一综述。     

Utilisation de la méthode du cubic simplex pour l'optimisation de la formulation a froid d'une emulsion de thioglycolate de calcium

The aim of this work relates to the optimization of a cold formulation of a depilatory emulsion containing thioglycolate of calcium, which presents the same characteristics as a reference product. To lead to this objective, a cubic simplex method was used. A preliminary formulation was preformed to evaluate the influence of each factor on the process formulation. The depilatory creams carried out present a rheological behaviour described by the model of Hershell-Bulkely, whose parameters are considered as responses of the optimizing system. This strategy allows both reducing and optimizing the number of experiments. The rheological measurements and the tests of stability showed that the use of an emulsifying polymer led to obtain a stable depilatory cream with a good effectiveness at a strong pH value.     

粟米乳酸发酵饮料乳酸菌种的筛选

本文以糖化的粟米为基质,对6株乳酸菌的发酵性能进行了测度,其中以嗜酸乳杆菌产酸最高,产酸速度最快,确定了嗜酸乳杆菌（La),乳明串珠菌（L1)和两歧双歧杆菌（Bb)为最佳菌种组合,并通过scheffe三因子单形重心设计法,确定了最佳种间比,即La:Ll:Bb=3:3:2.     

大豆组织蛋白丸子配方的优化研究

采用大豆组织蛋白为主料制作丸子,既能提高产品的营养价值,又能降低生产成本。通过单纯形格子法对大豆组织蛋白丸子配方进行研究分析,并利用质构仪来测定丸子的质地特征。结果表明：组织蛋白对丸子的弹性影响最大,大豆分离蛋白在咀嚼性、回复性和感官评定都起着重要作用。综合考虑成本与各因素指标,确定组织蛋白丸子配方为猪肉14.9%、大豆组织蛋白59.6%,大豆分离蛋白5%、变性淀粉13.4%、豆油7.1%,在该条件下制得丸子的弹性、咀嚼性、回复性和感官评定分别为0.921、1469.323、0.510和21.62,与预测值相对误差均在±1%以内,说明利用该方法建立的模型进行预测生产是可行的。     

The Finite Element Method in Thermal Processing of Foods

A variational finite element approach using triangular simplex and 2nd order quadrilateral elements was employed to analyze several problem areas that are of practical importance in the thermal processing of conduction heating products: (1) A method was developed to calculate conversion factors for thermal process design applicable to glass jars filled with conduction heating products. (2) The overshooting of temperatures after steam-off was studied, indicating that not including the contribution of overshooting to sterilization values in process design, can lead to gross overprocessing. (3) A method of correcting sterilization values to account for harmonious fluctuations in retort temperature was developed. (4) The air cooling of cans by natural convection was analyzed.     

Centroid Mapping Optimization: A New Efficient Optimization for Food Research and Processing

Experimenting at the centroid during simplex optimization was efficient in search for the optimum. A centroid search process, which replaced the worst vertex within the simplex with the centroid vertex one after another, was introduced. In the new method, the optimum can be found by combination of initial simplex, centroid search, mapping and simultaneous factor shift. An algorithm to define the new range for the subsequent simplex was also applied when the centroid search did not work effectively. This new method enabled efficient research by conducting a set of experiments simultaneously. By changing the range in sequential simplex/centroid search, the optimum could be more efficiently found than by previous simplex methods when compared with mathematical models.     

优选法在染整仿样试验中的应用

作者将数学家华罗庚的优选法灵活应用到了印染厂仿样打色板试验中,文中举例说明了"平分法"、"0.618法"和"分数法"三种优选法的使用方法,只要选择得当对于单峰问题各类试验都可应用优选法。     

浅谈硫酸根的重量法和容量法测定

硫酸根的重量法和容量法测定各有所长,当硫酸根小于1.00%其容量法测定可以替代重量法,只要相应条件控制好,一样可以获得精确的结果.