Lactobacillus reuteri-fortified camel milk infant formula: Effects of encapsulation,in vitro digestion,and storage conditions on probiotic cell viability and physicochemical characteristics of infant formula

Lactobacillus reuteri fortified camel milk infant formula (CMIF) was produced. The effect of encapsulation in different matrices (sodium alginate and galacto-oligosaccharides) via spray drying, simulated infant gastrointestinal digestion (SIGID), and storage conditions (temperature and humidity) on the viability of L. reuteri in CMIF and the physicochemical properties of CMIF were evaluated. Compared with free cells, probiotic cell viability was significantly enhanced against SIGID conditions upon encapsulation. However, L. reuteri viability in CMIF decreased after 60 d of storage, predominantly at higher storage humidity and temperature levels. At the end of the storage period, significant changes in the color values were observed in all CMIF, with a reduction in their greenness, an increase in yellowness, and a wide variation in their whiteness. Moreover, pH values and caking behavior of all CMIF stored at higher temperature (40°C) and humidity [water activity (a_w) = 0.52] levels were found to be significantly higher than the samples stored under other conditions. Over 30 d of storage at lower humidity conditions (a_w = 0.11 and 0.33) and room temperature (25°C), no significant increase in CMIF lipid oxidation rates was noted. Fourier-transform infrared spectroscopy analysis showed that, compared with the other storage conditions, CMIF experienced fewer changes in functional groups when stored at a_w = 0.11. Microscopic images showed typical morphological characteristics of milk powder, with round to spherical-shaped particles. Overall, camel milk fortified with encapsulated L. reuteri can be suggested as a promising alternative in infant formula industries, potentially able to maintain its physicochemical characteristics as well as viability of probiotic cells when stored at low humidity levels (a_w = 0.11) and temperature (25°C), over 60 d of storage.     

Green Measurements for Software Product Based on Sustainability Dimensions

Software is a central component in the modern world and vastly affects the environment’s sustainability. The demand for energy and resource requirements is rising when producing hardware and software units. Literature study reveals that many studies focused on green hardware; however, limited efforts were made in the greenness of software products. Green software products are necessary to solve the issues and problems related to the long-term use of software, especially from a sustainability perspective. Without a proper mechanism for measuring the greenness of a particular software product executed in a specific environment, the mentioned benefits will not be attained. Currently, there are not enough works to address this problem, and the green status of software products is uncertain and unsure. This paper aims to identify the green measurements based on sustainable dimensions in a software product. The second objective is to reveal the relationships between the elements and measurements through empirical study. The study is conducted in two phases. The first phase is the theoretical phase, where the main components, measurements and practices that influence the sustainability of a software product are identified. The second phase is the empirical study that involved 103 respondents in Malaysia investigating current practices of green software in the industrial environment and further identifying the main sustainability dimensions and measurements and their impact on achieving green software products. This study has revealed seven green measurements of software product: Productivity, Usability, Cost Reduction, Employee Support, Energy Efficiency, Resource Efficiency and Tool Support. The relationships are statistically significant, with a significance level of less than 0.01 (p = 0.000). Thus, the hypothesised relationships were all accepted. The contributions of this study revolve around the research perspectives of the measurements to attain a green software product.     

毛细管区带电泳-间接紫外检测法测定婴儿配方奶粉中的胆碱

目的建立毛细管区带电泳-间接紫外检测法测定婴儿配方奶粉中胆碱含量的新方法。方法用5 mmol/L乙酸提取婴儿配方奶粉样品中的胆碱,涡旋混匀、9000 r/min离心,上清液经0.45μm醋酸纤维素滤膜过滤后进样。用未涂覆熔融石英毛细管75μm×70 cm(有效长度:60 cm)作为分离柱。以10 mmol/L磷酸二氢钠+20 mmol/L磷酸+7 mmol/L 4-甲基咪唑为分离缓冲体系。分离电压为28 k V,进样压力及时间为0.5 psi、10 s,检测波长为214 nm。结果胆碱的校正峰面积与质量浓度在8.7~86.8 mg/L范围内间线性关系良好,相关系数为0.9997、检出限为2.6 mg/L、定量限为8.7 mg/L,方法的日内和日间精密度分别为1.9%和3.9%(n=7)。3个质量浓度添加水平的平均加标回收率分别为98.8%、95.2%及97.6%,相应RSD分别为0.8%、0.9%及0.6%(n=5)。用本法分析了10件婴儿配方奶粉样品,均获满意结果。结论本方法简单、无需有机溶剂,适用于婴儿配方奶粉中胆碱的常规检测。     

基于概率分析的核电传热管降质失效评估方法研究

发展核电是国家能源安全战略的重要组成部分，核电安全是对核电事业发展的最基本要求。依据核电传热管的检测历史数据和专家数据，利用全概率理论和Bayes公式提出了对传热管降质完整性评估的概率计算方法。通过对应力腐蚀、疲劳损伤等影响因素的分析，实现了在不同应力腐蚀和疲劳损伤条件下对传热管降质分布的概率计算。该评估方法可以将多个影响因素共同作用的复杂问题，简化为单个影响因素的逐一修正问题，简化了计算和处理方法。该方法可为核电蒸汽发生器传热管的降质概率评估提供借鉴。     

微生物法与试剂盒法测定婴幼儿配方奶粉中叶酸含量的方法比较

目的比较GB 5413.16-2010与试剂盒法测定的配方乳粉质控样品的叶酸含量。方法通过国标和试剂盒法各检测10组质控样品,得到20个检测数据,从检出限和相对标准偏差(relative standard deviation,RSD)对2种方法进行方法学考察。结果国标法和试剂盒法叶酸测试结果平均值分别为231μg/100 g和228μg/100 g,RSD分别为8.36%和8.01%。2个方法测定结果的平均值偏差为1.16%,RSD值偏差为2.14%。结论国标法与试剂盒法测定婴幼儿配方奶粉中叶酸含量的结果相近,实验室可以根据自身实际情况选择适合的检测方法。     

筛管压溃强度计算公式及适用性

针对筛管受地层中围压作用压溃失效缺乏通用计算分析模型的问题，利用ABAQUS软件建立了考虑初始椭圆度影响的平行布孔筛管有限元模型，研究外压作用下筛管的压溃行为。通过与文献中的实验结果对比表明，该有限元模型可准确地预测筛管的压溃强度。基于不同几何特征、材料特性以及布孔参数等筛管压溃强度数值模拟结果，建立了筛管压溃强度的简化计算公式。利用该计算公式，计算不同几何尺寸和材料属性的筛管压溃强度，与实验结果相比平均误差为7.0%。为了便于工程应用，分析了利用DNV，API等标准规范确定该公式中筛管对应的布孔前套管的静水压溃强度的可行性。结果表明，所建立的防砂筛管压溃强度计算公式可为实际工程中防砂筛管的强度预测与参数优化提供理论支持。     

Empirical surveys of frontier applications: a meta‐review

This contribution is the first attempt to systematically review all empirical surveys that so far have been made available in the broad field of efficiency and productivity analysis using frontier estimation methodologies. We provide a systematic bibliometric review on the many empirical surveys in the field of efficiency and productivity analysis, the most relevant concepts, areas, overlaps, and potentials to explore from its introduction to the most recent surveys. We combine the United Nations’ International Standard Industrial Classification (ISIC) taxonomy for the economic activity with the Journal of Economic Literature (JEL) classification system to classify the empirical surveys and to identify the current gaps in the literature. In addition to the most relevant/generic potential areas for applications (according to the United Nation's ISIC), this methodology provides a cluster analysis with the most relevant concepts that have been considered so far (according to the JEL codes). This overview brings an interesting guide for future work to develop the whole field.     

南海西部北部湾区域地层原油黏度预测方法

目前海上油田受多方面因素制约,地层流体取样少或无取样,而南海西部北部湾区域油藏流体性质变化较大,导致地层原油黏度难以准确预测。针对上述问题,通过收集北部湾区域已开发油藏地面及地层流体性质资料,分析影响原油黏度的主控因素,从主到次依次为含硫量、胶质含量、沥青质含量、含蜡量,其中胶质含量、沥青质含量和含硫量组合因素对原油性质影响显著,原油黏度对温度敏感,原油脱气前,压力对其影响小;运用数理统计学原理,建立了地面原油参数团、原油密度、地面脱气原油黏度与地层原油黏度间的3种评价方法,经乌石油田群15个样本点检验,平均绝对误差在0.5 mPa·s左右。该预测方法可为流体评价和油藏开发提供较为科学可靠的地层原油黏度资料。     

柱前衍生液相色谱荧光检测法测定婴幼儿配方乳粉中的低聚半乳糖

目的建立一种柱前衍生高效液相色谱荧光检测法测定婴幼儿配方乳粉中的低聚半乳糖含量的分析方法。方法样品用2-氨基苯甲酰胺衍生后,经色谱柱分离,用高效液相色谱-荧光检测器检测,外标峰加和分段法定量。结果建立的方法可以测定婴幼儿配方乳粉中的低聚半乳糖含量。采用麦芽糖、麦芽三糖、麦芽四糖、麦芽五糖、麦芽六糖和麦芽七糖建立标准曲线,在1～250μg/mL线性范围内相关系数(r~2)大于0.999。回收率为85.9%～103.5%,相对标准偏差(relative standard deviation, RSD)小于5%,检出限为1.0 g/kg,定量限为3.0 g/kg。结论本方法方法重现性好,精密度高,解决了婴幼儿配方乳粉中高含量乳糖对低聚半乳糖测定的干扰问题,可以为食品中低聚半乳糖的定量提供良好的解决方案。     

Impact of Divalent Ions on Heavy Oil Recovery by in situ Emulsification

Many reservoir formation brines are characterized by high salinity and contain high concentrations of divalent ions such as calcium, magnesium, and potassium. These challenging conditions can render the surfactants ineffective during chemical flooding for enhanced heavy oil recovery. Various brine types can have an impact on the stability of emulsions generated with chemicals as chemicals have various resistant levels toward hard divalent ions and salinities. To investigate the impact of brine hardness on heavy oil-in-water emulsion stability, glass tube experiments, microscopic visualization and sandpack flooding experiments, and Hele-Shaw visualization experiments were conducted in this study under low-salinity/hard-brine, high-salinity/hard-brine conditions using commercial chemicals, which are designed for specific reservoir brine conditions. Recovery results demonstrated that complex colloidal solution introduced in the previous study with silica and Dodecyltrimethylammonium bromide (DTAB) along with screened chemicals from glass tube tests in this study can enhance heavy oil recovery significantly with an addition of low concentration of xanthan gum (Lee and Babadagli 2018). The results confirmed the robustness of the complex colloidal solution formula to enhance oil recovery with low concentration of polymer under any reservoir brine conditions. The study also demonstrates the potential of polymer as an emulsion stabilization additive for enhanced heavy oil recovery by in situ emulsion generation. Polymer effects seemed to be particularly dominant under the low-salinity conditions than high-salinity conditions.