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1.
目的 麦胚孵育过程中蛋白酶将蛋白质水解成肽和氨基酸,多肽具有明确的生理活性和营养调节作用。本研究以麦胚为试验原料,采用微波辅助预处理的方法,研究孵育的温度、时间、pH及料液比4种因素对孵育后的蛋白酶活力及多肽含量的影响。 方法 通过单因素和响应曲面试验进行工艺条件优化。 结果 与未进行微波辅助预处理的样品相比,微波辅助处理(600 W, 10 s)能显著提高孵育后样品中的蛋白酶酶活力(约9.4倍)和肽含量(约3.1倍)。经过微波辅助处理后,孵育温度为51.5℃、pH为4.0、时间为6.33 h、料液比为1:7时,蛋白酶活力达最高为3826.24 U/g;孵育温度为45.0 ℃、pH为4.8、时间为8 h、料液比为1:7时,肽含量达最高为262.63 mg/g。 结论 微波辅助处理能有效的激活麦胚孵育液中的内源性蛋白酶活性,促进蛋白水解反应,显著提高孵育后的肽含量。该研究结果为麦胚多肽的制备新工艺开发提供了研究基础。  相似文献   
2.
ABSTRACT

The digital age of the future is ‘not out there to be discovered’, but it needs to be ‘designed’. The design challenge has to address questions about how we want to live, work, and learn (as individuals and as communities) and what we value and appreciate, e.g.: reflecting on quality of life and creating inclusive societies. An overriding design trade-off for the digital age is whether new developments will increase the digital divide or will create more inclusive societies. Sustaining inclusive societies means allowing people of all ages and all abilities to exploit information technologies for personally meaningful activities. Meta-design fosters the design of socio-technical environments that end-user developers can modify and evolve at use time to improve their quality of life and favour their inclusion in the society. This paper describes three case studies in the domain of assistive technologies in which end users themselves cannot act as end-user developers, but someone else (e.g.: a caregiver or a clinician) must accept this role requiring multi-tiered architectures. The design trade-offs and requirements for meta-design identified in the context of the case studies and other researchers’ projects are described to inform the development of future socio-technical environments focused on social inclusion.  相似文献   
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4.
The paper concerns an analysis of an equilibrium problem for 2D elastic body with two semirigid inclusions. It is assumed that inclusions have a joint point, and we investigate a junction problem for these inclusions. The existence of solutions is proved, and different equivalent formulations of the problem are proposed. We investigate a convergence to infinity of a rigidity parameter of the semirigid inclusion. It is proved that in the limit, we obtain an equilibrium problem for the elastic body with a rigid inclusion and a semirigid one. A parameter identification problem is investigated. In particular, the existence of a solution to a suitable optimal control problem is proved.  相似文献   
5.
东营凹陷王庄-宁海地区流体包裹体分析与流体充注研究   总被引:5,自引:4,他引:1  
利用流体包裹体分析技术,系统地分析了东营凹陷王庄-宁海地区覆盖所有含油层位的流体包裹体样品。包裹体荧光观察和均一温度特征分析揭示了包裹体发育期次为5期,说明该区油藏存在5次流体充注过程;据此确定了备期烃类的成藏期次。东营组沉积时期和明化镇组沉积末期的油气运聚均在成藏后遭受大气淡水淋滤和降解作用。沙三段原油可能经历至少2期稠油化作用。荧光观察进一步证实该区主要发生2期充注、2期成藏。  相似文献   
6.
选用β环糊精(β-CD)和羟丙基-β环糊精(HP-β-CD)的水溶液分离混合烃中的苯,通过比较得出HP-β-CD对苯的分离具有较高的选择性。在重整原料油中采用HP-β-CD实现液-液分离,运用正交实验设计方法设计实验,得出最佳分离条件为:HP-β-CD溶液的含量30%,HP-β-CD溶液与重整汽油的体积比3:1,萃取次数9。在此工艺条件下,萃取后重整汽油中的苯含量从5.72%降到1.08%。  相似文献   
7.
使用金相显微镜、扫描电镜及X射线能谱和波谱观察并分析了NdFeB烧结材料中夹杂物的形态、数量和组成。磁粉制备后立即烧结的NdFeB磁体中的夹杂物是氧化钕;而在不同环境条件下放置后的NdFeB粉再烧结的材料中发现,除了氧化钕的夹杂物外,还有钕的氮化物及钕的氮氧复合夹杂物。同时还论讨了这些夹杂物对于NdFeB材料磁性能的影响。  相似文献   
8.
本文提出一个同温冶炼过程中预测非金属夹杂物沉淀的计算机程序。本研究中,多元硅酸盐溶体的Gibbs自由能由基于统计热力学的晶胞模型来计算,该晶胞模型按照氧与周围的阳离子构成的对称和非对称晶胞来描述硅酸盐熔体结构,假定高温冶炼时认与非金属夹杂物平衡,钢液中氧化物元素的活度由Wagner交互作用系数来计算,利用本程序可以估计炼钢时沉淀的非金属氧化物的成分,为调整冶炼工艺和提高产品质量提供指导,进一步可计  相似文献   
9.
Some approximate solutions for predicting the stress intensity factor of a short crack penetrating an inclusion of arbitrary shape have been developed under mode I and mode II loading conditions. The derivation of the fundamental formula is based on the transformation toughening theory. The transformation strains in the inclusion are induced by the crack-tip field and remotely applied stresses, and approximately evaluated by the Eshelby equivalent inclusion theory. As validated by detailed finite element (FE) analyses, the developed solutions have good accuracy for different inclusion shape and for a wide range of modulus ratio between inclusion and matrix material.  相似文献   
10.
Education-driven research in CAD   总被引:1,自引:0,他引:1  
Jarek   《Computer aided design》2004,36(14):1461-1469
We argue for a new research category, named education-driven research (EDR), which fills the gap between traditional field-specific research that is not concerned with educational objectives and research in education that focuses on fundamental teaching and learning principles and possibly on their customization to broad areas (such as mathematics or physics), but not to specific disciplines (such as CAD). The objective of EDR is to simplify the formulation of the underlying theoretical foundations and of specific tools and solutions in a specialized domain, so as to make them easy to understand and internalize. As such, EDR is a difficult and genuine research activity, which requires a deep understanding of the specific field and can rarely be carried out by generalists with primary expertise in broad education principles. We illustrate the concept of EDR with three examples in CAD: (1) the Split and Tweak subdivisions of a polygon and its use for generating curves, surfaces, and animations; (2) the construction of a topological partition of a plane induced by an arbitrary arrangement of edges; and (3) a romantic definition of the minimal and Hausdorff distances. These examples demonstrate the value of using analogies, of introducing evocative terminology, and of synthesizing the simplest fundamental building blocks. The intuitive understanding provided by EDR enables the students (and even the instructor) to better appreciate the limitations of a particular solution and to explore alternatives. In particular, in these examples, EDR has allowed the author to: (1) reduce the cost of evaluating a cubic B-spline curve; (2) develop a new subdivision curve that is better approximated by its control polygon than either a cubic B-spline or an interpolating 4-point subdivision curve; (3) discover how a circuit inclusion tree may be used for identifying the faces in an arrangement; and (4) rectify a common misconception about the computation of the Hausdorff error between triangle meshes. We invite the scientific community to encourage the development of EDR by publishing its results as genuine research contributions in peer-reviewed professional journals.  相似文献   
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