泛函微分方程完全全局渐近稳定的Pazumikhin型定理

给出了泛函微分方程ｘ（ｔ）＝ｆ（ｔ，ｘｘ）及其被扰动方程ｘ（ｔ）＝ｆ（ｔ，ｘｔ）＋ｇ（ｔ，ｘｔ）的零解为完全全局渐近稳定的一个Ｒａｚｕｍｉｋｈｉｎ定理，推广和改进了有关结果。     

泛函微分方程完全全局渐近稳定的Razumikhin型定理

给出了泛函微分方程ｘ（ｔ）＝ｆ（ｔ，ｘｘ）及其被扰动方程ｘ（ｔ）＝ｆ（ｔ，ｘｔ）＋ｇ（ｔ，ｘｔ）的零解为完全全局渐近稳定的一个Ｒａｚｕｍｉｋｈｉｎ定理；推广和改进了有关结果     

变系数超泛函微分方程非振动解的渐近性

研究了具有变系数的时超泛微分方程ｘ′（ｔ）＋ｐ（ｔ）ｘ（ｔ＋τ）－Ｑ（ｔ）ｘ（ｔ＋σ）＝０（＊）其中，ｐ（ｔ），Ｑ（ｔ）∈Ｃ（ｔ０，＋∞），Ｒ＾＋），τ，σ∈Ｒ＾＋（０，＋∞）解的振动性与非振动解的渐近性问题，获得了方程（＊）非振动解渐近的有关判据。     

一维抛物型方程的高精度分支稳定显格式

利用特定参数法,对一维抛物型方程构造出了一个截断误差为Ｏ（△ｔ＾２＋△ｘ＾４）的分支稳定显格式,其稳定性条件为ｒ＝ａ△ｔ／△ｘ＾２〈１／２。     

非驻定系统零解的同等渐近稳定性的一个判据

在较弱的条件下给出了一般非驻是系统ｘ＝ｆ（ｔ，ｘ）解的同等渐近稳定性的一个判别定理，改进和补充地有关结果。     

具强迫力的一阶中立型微分方程的振动性

考虑具强迫力的一阶中立型微分方程ｄ／ｄｔ「ｘ（ｔ）－Ｒ（ｔ）ｘ（ｔ－τ）」＋Ｐ（ｔ）ｘ（ｔ－σ）＝ｆ（ｔ），ｔ≥ｔ０这里０≤Ｒ（ｔ）〈Ｃ〈１，Ｃ为正常数，得到了方程的所有解都振动的一个充分条件。     

一类n维非自治非线性系统的周期解

应用Ｓｃｈａｕｄｅｒ和Ｒｏｔｈ不动点定理，给出了系统ｘ＝Ａｘ＋ｇ（ｔ，ｘ）ｘ∈Ｒ＾ｎ存在周期解的一组充分性条件。     

一阶中立型时滞微分方程的振动性

研究一阶中立型微分方程ｄ／ｄｔ「ｘ（ｔ）＝ｐ（ｔ）ｘ（ｔ－ｒ（ｔ））」＋ｑ）ｔ）ｘ（ｔ－σ（ｔ））＝０,ｔ≥ｔ０,（Ｅ）其中ｐ（ｔ）,ｑ（ｔ）,ｒ（ｔ）,σ（ｔ）是「ｔ０,∞）上的非负连续函数,得到了方程（Ｅ）所有解振动的充分性判据,所得结果包含或改进了已有文献的相关结果。     

酒石酸稳定性预测的曲线方程拟合

本文以有关的实验数据为基础,拟合出用于酒石酸稳定性预测的酒石酸氢根百分比（％ＨＴ－）方程式：Ｚ＝－Ｐ（ｘ）ｙ２＋Ｑ（ｘ）ｙ－Ｒ（ｘ）。Ｚ为（％ＨＴ－）,ｘ为乙醇浓度（ＥｔＯＨ（％ｖ／ｖ））,ｙ为ｐＨ值。Ｐ（ｘ）,Ｑ（ｘ）及Ｒ（ｘ）分别为ｘ的函数。该方程可用于对酒石酸稳定性判别的微机电算,且可用于葡萄酒生产中ＫＨＴ↓生成的最佳酸度确定,及沉淀分离后溶液中酒石酸稳定性控制的酸度选择。     

关于一类模糊积分方程解的存在唯一性

利用Ｆｕｚｚｙ压缩映象的不动点定理证明了一类线性Ｖｏｌｔｅｒａ型Ｆｕｚｚｙ积分方程ｆ（ｘ）＝φ（ｘ）＋λ∫ｘｘ０Ｋ（ｘ，ｔ）ｆ（ｔ）ｄｔ解的存在唯一性定理．     

Computational strategies for national integration of phenotypic, genomic, and pedigree data in a single-step best linear unbiased prediction

The single-step genomic BLUP (SSGBLUP) is a method that can integrate pedigree and genotypes at molecular markers in an optimal way. However, its present form (regular SSGBLUP) has a high computational cost (cubic in the number of genotyped animals) and may need extensive rewriting of genetic evaluation software. In this work, we propose several strategies to implement the single step in a simpler manner. The first one expands the single-step mixed-model equations to obtain equivalent equations from which the regular (including pedigree and records only) mixed-model equations are a subset. These new equations (unsymmetric extended SSGBLUP) have low computational cost, but require a nonsymmetric solver such as the biconjugate gradient stabilized method or successive underrelaxation, which is a variant of successive overrelaxation, with a relaxation factor lower than 1. In addition, we show a new derivation of the single-step method, which includes, as an extra effect, deviations from strictly polygenic breeding values. As a result, the same set of equations as above is obtained. We show that, whereas the new derivation shows apparent problems of nonpositive definiteness for certain covariance matrices, a proper equivalent model including imaginary effects always exists, leading always to the regular SSGBLUP mixed model equations. The system of equations can be solved (iterative SSGBLUP) by iterating between a pedigree and records evaluation and a genomic evaluation (each one solved by any iterative or direct method), whereas global iteration can use a block version of successive underrelaxation, which ensures convergence. The genomic evaluation can explicitly include marker or haplotype effects and possibly involve nonlinear (e.g., Bayesian by Markov chain Monte Carlo) methods. In a simulated example with 28,800 individuals and 1,800 genotyped individuals, all methods converged quickly to the same solutions. Using existing efficient methods with limited memory requirements to compute the products Gt and A(22)t for any t (where G and A(22) are genomic and pedigree relationships for genotyped animals, and t is a vector), all strategies can be converted to iteration on data procedures for which the total number of operations is linear in the number of animals + number of genotyped animals × number of markers.     

Water-absorption rate equation of rice for brewing sake

This study was undertaken to analyze the kinetics of water absorption and to derive an equation for the rate at which water is absorbed by rice for brewing sake. We used two rice varieties: Gin-oumi, commonly used as a staple food, and Gohyakumangoku, a variety used particularly for brewing sake. The water-absorption rate equations of Gin-oumi and Gohyakumangoku were postulated based on the following equations. For Gin-oumi (water content, 11.5%), dx/dtheta=k(1-x)(n), n=1, k=(2 x 10(-9))exp(0.0604 x (t+273.15)). For Gohyakumangoku (11.5%), dx/dtheta=k(1-x)(n)(x+a), n=1, a=0.29, k=(2 x 10(-8))exp(0.0534 x (t+273.15)). Here, x, theta (min), and t ( degrees C) are the water absorbing ratio, time, and temperature, respectively. The result shows that the values of the temperature-dependence parameter k (min(-1)), as well as its curves, are different; a typical rice grain has a monotonically smooth curve, whereas that suitable for sake brewing has an S-shaped curve.     

超声辐照马铃薯淀粉糊降解动力学的研究(英文)

本文进行了超声辐照时间对超声辐照降解马铃薯淀粉糊的动力学的研究。研究结果表明,淀粉糊重均分子量和特性粘度随辐照时间的延长而降低;而且趋于一个极限值。在处理条件下,超声降解动力学方程式为:Mt=50.97×104+572.77×104e-0.216t,ηt=0.81+6.556×e-0.229t。马铃薯淀粉糊分子链剪切在初始阶段是随机的,然后是非随机剪切。     

Estimation of chemical carcass composition from 8th rib characteristics with Belgian blue double-muscled bulls

Characteristics from the 8th rib cut: chemical composition, tissue composition after dissection, specific gravity (SG) and m. longissimus thoracis (LT) composition, collected on 17 Belgian Blue double-muscled fattening bulls were used to generate equations for predicting chemical carcass composition. Carcass composition was best predicted from chemical analysis of the 8th rib cut and the empty body weight (EBW) of the bull. Carcass chemical fat content (CCF, kg) was predicted from the 8th rib cut fat content (ether extract, 8RF, kg) by the following regression: CCF=1.94+27.37 8RF (R(2)=0.957, RSD =9.89%). A higher coefficient was found for carcass water (CCW, kg) predicted from 8RF and EBW: CCW=-2.26+0.28 EBW-34.28 8RF (R(2)=0.997, RSD=1.48%). No parameter was found to improve the prediction of CCP from EBW solely: CCP=-0.86+0.08 EBW (R(2) =0.992, RSD=2.61%). Prediction equations based solely on LT composition had low R(2) values of between 0.38 and 0.67, whereas no significant equations were found using SG. However, equations based on EBW had R(2) values between 0.78 and 0.99. Chemical components of the 8th rib cut in combination with EBW are most useful in predicting the chemical composition of the carcass of Belgian-Blue double-muscled bulls.     

线性参数微分代数方程组的参数分离方法

提出了线性控制参数的微分人数方程组的状态变量和控制参数的分离方法，并对由此产生的方程组的稳定性问题和连续性问题作了分析。     

求解随机微分方程半隐无导数法的稳定性

数值方法的有效性对于求解随机微分方程是很重要的,稳定性就是衡量其合理性的标准之一.讨论了在噪声为乘性噪声的条件下,半隐无导数法用于求解标量自治随机微分方程的均方稳定性和指数稳定性,并给出了半隐无导数法用于求解标量自治随机微分方程的均方稳定性和指数稳定性的条件,同时指出半隐无导数法用于求解标量自治随机微分方程的均方稳定性和指数稳定性是等价的.     

胡萝卜中类胡萝卜素的提取动力学

使用抗坏血酸和2,6-二叔丁基-4-甲基苯酚保护剂,以石油醚-丙酮（体积比4∶1）混合液为提取剂,分别用水浴直接提取法、超声辅助提取法和微波辅助提取法从胡萝卜粉中提取类胡萝卜素。采用不同温度和原料粒度进行从胡萝卜粉中提取类胡萝卜素的提取动力学实验。结果表明,水浴法和超声辅助法是符合反应-内扩散控制的动力学模型,所得提取动力学方程分别为：1）水浴法：y=0.009 9t＋0.110 7（R2=0.920 9,30 ℃）、y= 0.018 6t＋0.096 1（R2=0.893 7,40 ℃）、y=0.018 2t＋0.088 6（R2=0.965 7,45 ℃）;2）超声辅助法：y=0.001 1t＋0.080 9（R2= 0.917 9,30 ℃）、y=0.001 6t＋0.043 9（R2=0.978 8,40 ℃）、y=0.001 8t＋0.039（R2=0.964 2,45 ℃）。表观活化能分别为Ea（水浴）=－26.825 1 kJ/mol和Ea（超声）=－35.196 5 kJ/mol。而微波辅助法则是符合混合控制的动力学模型,其方程为y=0.027 5t＋0.344 6（R2=0.972 3,30 ℃）、y=0.031 9t＋0.426 5（R2=0.868 9,40 ℃）、y=0.058 7t＋0.275 1（R2=0.973 4,45 ℃）,表观活化能为E a（微波）=－36.105 2 kJ/mol。通过水浴法考察原料粒度对提取动力学的影响,结果表明原料粒度对提取速率和提取率的影响程度是60～80 目＞40～60 目＞20～40 目,即粒度越细越有利于类胡萝卜素的提取。     

MATHEMATICAL MODEL TO PREDICT YIELD LOSS OF MEDIUM AND LARGE TIGER SHRIMP (PENAEUS MONODON) DURING COOKING

Cooking causes moisture loss and reduces the yield of shrimp. This can be affected by its size, cooking temperature and time. A finite difference mathematical model to predict temperature distribution during heating/cooling of shrimp was modified to enable prediction of yield loss. The relationship between cooking temperature, time and yield loss was determined by isothermal experiments. For medium and large Tiger shrimp (Penaeus monodon), data were fitted into the following form: % Yield Loss = a + b*T + c *T²+ d*t²+ e*t + f*T*t where T is temperature and t is time. These equations were used in the model. Each volume element in the model was allowed to have its own yield loss; and overall yield loss was found by calculating mass average values. Experiments were conducted to cook Tiger shrimp under regular conditions and determine its yield loss, and the predictions of the model were compared with experimental data. Close agreement was obtained. This model can be used to predict yield losses during cooking of shrimp.     

桑葚渣多酚提取物冻干粉的制备及稳定性分析

桑葚渣是一种潜在的多酚类食品功能成分,但其氧化和热降解稳定性低,限制了其实际应用.本研究以副产物桑葚渣为原料,制备一种醇溶液提取物,添加冻干保护剂得到7种不同的桑葚渣多酚提取物冻干粉(P1～P7).结果表明,添加不同冻干保护剂后的桑葚渣多酚提取物冻干粉的总酚含量(单独添加麦芽糊精组除外)及抗氧化活性均有所提高,但单体花...     

紫甘蓝花色苷稳定性及热降解动力学研究

为有效控制紫甘蓝加工过程中花色苷的降解,研究了pH、温度、光照、金属离子及外源添加物对花色苷稳定性的影响。实验表明,紫甘蓝花色苷稳定性受pH、温度和光照影响较大,pH2.0左右的花色苷5 h保存率仍有92.92%±0.69%、40℃下避光5 h花色苷保存率有70.50%±0.52%,花色苷稳定性较强;添加不同浓度的金属离子（K+、Mg2+、Na+）低浓度Fe3+（0.01~0.02 g/mL）及抗坏血酸（0.03 g/mL）、蔗糖和乳糖均可提高花色苷稳定性;氧化剂H₂O₂及还原剂Na₂SO₃、高浓度Fe3＋（0.03~0.04 g/mL）和抗坏血酸（0.09和0.12 g/mL）均加快花色苷降解,且降解速率随浓度增大而增加。花色苷热降解符合一级动力学,降解速率随温度升高而增加,半衰期随之减小,50℃ pH2.0的t_1/2最大为67.28 h,活化能最大为39.16 kJ/mol,为吸热非自发反应。采用紫甘蓝花色苷加工产品时,应尽量使温度低于40℃或者控制pH在2.0左右、选择提升或者不影响花色苷稳定性的辅料,于避光环境下操作及储存。