超高温灭菌乳货架期加速试验的研究

In order to estimate the shelf-life of cow milk sterilized by instant treated with Ultra Heat Temperature(UHT) in a relatively short time, the accelerated shelf-life testing (ASLT) was designed and conducted, selecting the histological change of the sterilized milk caused by fat droplets creaming as its criteria.The stability index (SI) and the viscosity variation of the sterilized milk were determined at preservation conditions of 20, 25, 30, 35, 40 and 45℃, using Turbiscan technology.The result showed that the SI was slightly higher for 25℃ than for 20℃, elevating linearly for temperature from 25℃ to 40℃, and decreased for 40℃ to 45℃.The SI data for 25℃ to 40℃ were fitted well with equation SI_t=0.062t-1.382 (R²=0.990).If a ratio SI_t/SI_25℃ called as accelerated ratio (AR) was defined, the AR values calculated from the equation were 3.6,4.3 and 5.0 for 35, 37.5 and 40℃, respectively, which were agreement with the data from ASLT.So, the model could be used for the prediction of the shelf-life of sterilized milk by UHT process.     

鲜切梨货架期生理及品质的研究

文章以鲜切梨为试验材料,研究在12℃和常温(25℃)贮藏条件下,鲜切梨货架期间生理指标和品质指标的变化。实验结果表明:12℃的贮藏温度显著抑制了鲜切梨的失重率和呼吸强度,抑制了多酚氧化酶(PPO)和过氧化物酶(POD)的活性,延缓了鲜切梨的褐变,其营养成分和感官特性均得以较大限度的保留。     

试论LNG泄露后果的预测模型

随着液化天然气开采活动的不断增多,液化天然气储罐研制行为不断跟进,根据气体性质以及存储、运输需要,确保所研制的储罐能够充分发挥应用性能,以免气体运输过程中出现泄漏现象,减少液化天然气浪费。本文首先对液化天然气做了基本介绍,然后运用燃气浓度扩散模型、计算流体动力模型进行泄漏后果预测、分析,最后对其进行模型验证、探索发展方向。     

水平井产能预测模型研究

本文分析了目前采油工程与油藏工程中广泛采用的几种水平井产能预测公式,并指出其不足之处,为进一步提高产能预测的准确性,本文建立了产能预测半解析模型。该模型运用镜像反映和势叠加原理分段进行油藏渗流和井筒流动的耦合,并通过迭代计算求得整个油井产能。经现场实际验证,利用该模型计算得到的值与现场实测值相对误差小于16％,与四种水平井产能解析模型的计算值相比精度更高。     

Matlab在微生物生长预测模型中的应用

利用Matlab构建了一个微生物仿真系统,在形成仿真函数库的基础上,结合VC 6.0编程软件,最终开发出独立于Matlab的软件系统.     

邯钢焦化厂焦炭预测模型的研究

随着高炉的大型化和富氧喷煤技术的应用,对焦炭质量提出了更高的要求,利用单种煤和配合煤的各种试验室测定的性能指标来预测焦炭质量,可以减少小焦炉配煤试验,以最少的试验室投入,确     

燃机电厂主要经济指标预测模型

建立燃机经济指标计算模型,可输入启停次数、平均负荷,从而得出各项经济指标,依据模型得出启停次数与煤耗、负荷率与煤耗的关系曲线。     

甲醇含量预测模型的研究

运用径向基函数网络结合偏最小二乘回归的方法建立了甲醇合成反应器出口甲醇含量的预测模型。验证表明,该模型用于反应器出口甲醇含量的预测,效果良好。     

基于SSA-MIC-SMBO-ESN的水质预测模型

水污染事件威胁人类生产和生活安全,提前预测水质变化对水污染的快速反应具有重要意义。基于水质数据的时序性,引入泄漏积分型回声状态网络(ESN),以莆田市东圳水库水质监测站的10种水质指标数据作为样本,分别构建DO、COD_Mn、TP的水质预测模型。首先,在用邻近点线性趋势法对缺失值进行填充,用Z-score法和邻近点线性趋势法对异常值进行检测修正的基础上,用奇异谱分析(SSA)算法对水质数据进行平滑降噪处理;然后,采用最大互信息系数(MIC)衡量水质指标之间的相关度,选取相关系数较大的水质指标作为待预测水质指标的输入特征;最后,利用ESN构建基于多特征的水质预测模型,其中采用序列模型优化(SMBO)算法对模型的超参数进行优化。试验结果表明,构建的DO、COD_Mn和TP的SSA-MIC-SMBO-ESN水质预测模型都具有较高的预测精度,适合实际应用。     

企业人力资本培训投资收入的预测模型

论述进行企业人力资本培训投资收入预测的意义.阐述企业人力资本培训投资收入的涵义,提出一线生产工人培训投资收入的类比预测模型和专家预测模型,以及技术人员和管理人员培训投资收入的类比预测模型和专家预测模型.     

不同膜的真空包装对澄海猪头粽的保鲜性研究

通过涂膜法制备得到壳聚糖/PE复合膜和壳聚糖/纳米ZnO/PE复合膜,并分别对澄海猪头粽进行真空包装,在储存期第0、2、4、6天,通过测量感官特性、色度、TBARS值,比较膜的保鲜效果。结果发现,随着储存时间的增加,每组猪肉粽都出现了不同程度的腐变。与普通PE膜的真空包装相比,壳聚糖/PE复合膜和壳聚糖/纳米ZnO/PE复合膜对猪头粽都有一定的保鲜效果,其中壳聚糖/纳米ZnO/PE复合膜的保鲜效果略好。     

Predicting dielectric tunability of compositionally-graded barium strontium titanate thin films on metal substrates by thermodynamic modeling

Dielectric properties of compositionally-graded barium strontium titanate (BST) thin films respectively on Ti and stainless steel (SS) plates were computed using a modified thermodynamic model. Calculated results predict that higher dielectric constant and tunability can be obtained when the films are onto Ti substrates, which have smaller thermal expansion coefficient (TEC). For Ti substrates, “up-graded” films (Ba/Sr ratio increases from substrate to surface) exhibit higher tunability than “down-graded” films; whereas “up-graded” films on SS plates have relatively lower tunability. The received larger dielectric constant and tunability are because of smaller total out-of-plane polarization, which is resulting from smaller total compressive strain. The calculated dielectric constant and tunability of such graded films are in accordance with those of the films fabricated via sol-gel approaches, indicating that the dielectric behavior of ferroelectric films can be adjusted by designing compositional gradient.     

降低玻璃内装质量损失的措施探讨

从质量查询反馈中看,内装质量投诉较多,是主要的质量损失,本文讨论了几种降低玻璃内装质量损失的方法。     

高温沙漠地区隔热耐磨单层衬里整体现浇法施工

结合工程实例,介绍了在高温沙漠地区,在社会依托条件和气候条件都很差的情况下,为控制隔热耐磨单层衬里的整体质量,采取了有效降温、加入缓凝剂、控制水化热、合理制作安装模板、严格衬里混凝土的加工及浇注、切实可行的施工部署等措施,确保了“整体现浇法”的顺利实现。     

Predicting Bond Strength

Methods are presented for predicting the load carrying capability of a bonded joint using relatively simple laboratory test samples. It is first shown that using an average stress criterion can lead to errors of an order of magnitude in predicted load carrying capability. A fracture mechanics approach is then shown to predict failure load accurately in a joint bonded with either a polyurethane or a relatively brittle epoxy when proper consideration is given to loading mode, temperature, and load rate. The principal contribution of this paper is in extending fracture mechanics theory to regions where classical singular points do not exist. Analyses are combined with test data to deduce an “inherent” flaw size.     

Predicting solubilities of vinyl polymers

Accurate solubility limits of polymers are best expressed by molecular weight fractionation curves. Individual curves may be obtained for each polymer–solvent (–nonsolvent) system. A method for predicting solubility behavior, based on solubility parameter δ and hydrogen bonding index γ, is proposed here. The correlation is of the form where [η] = intrinsic viscosity of precipitated polymer; T = absolute temperature; (v.f.) = volume fraction of solvent; R = (δ_s ? δ_n) ? 0.3(γ_s ? γ_n); Q = (γ_p ? γ_e)^2.2/(δ_p ? δ_e); p refers to polymer; s refers to solvent; n refers to nonsolvent; e refers to solvent system at theta temperature; and a,b,c, and k are fitted constants. The correlation was derived from data for poly(vinylpyrrolidone) and polyacrylamide. It probably is limited to systems in which the precipitate occurs as a liquid.     

表面活性剂溶液行为预测（英）

开发了Ｐｒｅｄｉｃｔ和Ｍｉｘ两个软件程序,应用该程序可以预测表面活性剂溶液行为,这些预测结果对配方师很有价值。对Ｐｒｅｄｉｃｔ和Ｍｉｘ预测的溶液行为与化妆品的表面性质、粘度、刺激性及相稳定性有很好的关联性     

Predicting valve tray efficiency

Existing literature models for predicting the mass transfer efficiencies of binary hydrocarbon, distillation columns employing moving valve trays are evaluated. Only four models for predicting valve tray efficiencies exist in the open literature. All of these models use data from valve trays. The last theoretical model was published in 1972, 42 years ago. By comparison, sieve tray efficiency models are numerous and recent. Sieve tray models were developed from large databases. There are no valve tray equivalents to the fundamental mechanistic models available for sieve trays. Despite the differences between valve and sieve trays, many of the phenomena on sieve and valve trays are similar. Consequently, sieve tray models can be employed to provide estimates for valve trays. In this work, using public FRI data on round moving valves, the performance of the Chen and Chuang sieve tray mechanistic model is compared to the performance of four valve tray models. It appears that, in the absence of fundamental (and qualified) valve tray models, the sieve tray models present a potential alternative for valve tray efficiency predictions.