用热处理方式改善Cr12MoV钢中网状碳化物

Ｃｒ１２ＭｏＶ钢是重要的工模具钢，钢中网状碳化物的存在造成工模具早期开裂的主要原因，本试验采用延长奥氏体加热时间的方法，改善了钢中网状物的形态。     

基于Gleeble3500热模拟试验机的GCr15钢共析相变点测定

通过Gleeble3500热模拟试验机测定GCr15钢在升温和降温时的膨胀曲线,并结合Origin8.0软件分析技术分析膨胀曲线,采用切线法采集数据;结合不同温度等温水冷实验试样碳化物形貌和试样的洛氏硬度,确定离异共析转变温度。实验结果表明:GCr15钢加热到840/℃保温5分钟,然后以1℃/s的速度冷却,加热时的共析转变开始温度为756℃,结束温度为807℃;冷却时共析转变开始温度为743℃,结束温度为644℃;GCr15钢在805℃保温30分钟后,在715℃以上的共析转变为离异共析转变,645℃等温开始出现片状珠光体。     

65钢在真空加热及冷却时的组织转变

用高温金相显微镜连续观察了 6 5钢奥氏体晶粒的长大过程及高温奥氏体孪晶的形成 ,分析了该钢试样加热及冷却后的室温组织 ,并用剥层分析法阐明了试样表层的脱碳现象。在冷却过程中没有看到先共析铁素体和珠光体转变时的动态过程 ,但从未经浸蚀的室温组织的着色及位置、形态的不同 ,分析了上述组织的形核地点及核长大的特征     

原始组织对Cr12Mov钢螺纹钢丝辊断裂的影响及改进措施

Ｃｒ１２ＭｏＶ钢的原始组织中不良的碳化物形态和分布状态造成轧辊断裂早期失效，改进了锻造工艺及热处理工艺，轧辊的断裂现象基本消除。     

INACTIVATION OF FICIN PROTEOLYTIC ACTIVITY IN THE PRESENCE OF ASCORBIC ACID AND Cu2+-IONS

The simultaneous presence of ascorbic acid, Cu²⁺ions and oxygen causes irreversible ficin inactivation. The degree of inactivation is dependent on the concentration of inhibitors. Relatively higher decrease of ficin proteolytic activity was found with high molecular substrate, hide powder azure, than with a low molecular one, N-benzoyl-L-arginine-p-nitroanilide. Gel chromatography on Sephadex G-50 showed that ficin inactivation is not due to the destruction of its molecule resulting in the decrease of its molecular weight. Inactivation of ficin proteolytic activity was associated with a partial drop in ficin immunoreactivity.     

可靠性技术的发展和印刷领域中的可靠性

本文从综述国内外可靠性的发展概况出发,阐明了在印刷领域开展可靠性研究的必要性和紧迫感。然后提出了在印刷领域开展可靠性的方略。     

纺粘法非织造布生产技术改造及产品开发

简介了聚丙烯纺粘法非织造布的生产工艺，讨论了诸如纺丝温度、侧吹风、 牵伸风、泵供量、摆丝幅度、摆丝频率以及压延机热压合温度和压力等对纺粘法非 织造布质量的影响，并介绍了该厂设备幅宽改造、边角料回收系统改造、节电改造 以及产品开发的情况。     

膜分离技术在果蔬汁生产中的应用

介绍了膜分离技术在果蔬菜汁澄清，脱苦，浓缩等方面的应用，探索了利用膜联合过程生产高品质质果蔬汁的实际可能性。     

非油炸型速冻马铃薯预处理加工工艺参数的研究

传统的速冻马铃薯产品大部分都采用了油炸工艺，而马铃薯高温油炸时会产生致癌物质丙烯酰胺，对人体有害。为了开发食用安全的速冻马铃薯新品种，采用正交试验和综合评分，对非油炸型速冻马铃薯的预处理加工工艺条件进行了研究。研究了马铃薯品种（A）、热烫温度（B）、热烫时间（C）和马铃薯直径（D）对速冻后产品的失重率、硬度、多酚氧化酶活性和过氧化氢酶活性的影响。结果表明：试验因子对其影响的主次顺序为B〉C〉A〉D；最佳方案为A4B3C2D2即以中薯3号为原料．马铃薯直径为4．5cm，110℃热烫3min。产品的品质最佳。     

条斑紫菜蛋白和多糖提取工艺优化

以条斑紫菜为原料，采用超声辅助提取蛋白和多糖、通过单因素试验和正交试验，确定了最佳的提取工艺条件。     

金针菇营养保健果冻的生产工艺

研究金针菇营养保健果冻的加工过程中,复合凝胶剂魔芋粉-琼脂-明胶的配比、凝胶剂的用量、柠檬酸与蔗糖的添加量、煮胶温度和时间对果冻产品品质的影响.结果表明:魔芋粉、琼脂、明胶的配比为2:3:2,总用胶量为0.7%,混合溶解后的胶溶液在75℃煮10min,添加15%的白砂糖,调至pH=5,加入金针菇提取液,凝固后获得透明,口感爽滑,酸甜可口的果冻,具有清香纯正的金针菇风味.     

THE EFFECT OF TEMPERATURE ON THE RHEOLOGY OF BUTTER, A SPREADABLE BLEND AND SPREADS

The texture of lipid-based food materials is an important topic for investigation. In this study, the rheological properties of five edible fats were determined. A puncture test was performed to investigate the rheological properties of the food materials at 5C and at 19C using a texture analyzer. The force-displacement measurements were converted to stress–strain by assuming incompressibility of edible fat food materials in a linear viscoelastic region (LVR). Young's modulus of each edible fat was calculated using stress–stain curves in a LVR. Shear elastic moduli of edible fats in a LVR were obtained using a rheometer. Further to that the effect of temperature on storage modulus and loss modulus and creep test were obtained using a rheometer. The tests showed good correlation between Young's modulus and shear elastic modulus for each material. The mechanical properties correlated well with the structural properties of each of the materials.

PRACTICAL APPLICATIONS

The texture of butter, blends and spreads is determined by temperature, rheological properties, processing conditions and the composition of the material. Our research investigated the effect of temperature on the rheological properties of these foods. The results may be used to model the relationship between the microstructure and mechanical properties of the fat crystal network.     

胡芦巴种子中半乳甘露聚糖脱色、脱蛋白工艺研究

采用乙醇回流法考察了影响由胡芦巴种子提取的半乳甘露聚糖脱色效果的因素,并应用L9(34)正交实验设计优化脱色工艺条件.结论:影响脱色效果的主次因素顺序为;脱色次数＞脱色时间＞料液比,最佳的工艺条件是:脱色时间为120min,料液比为1∶12(g/mL),脱色次数为3次.在此基础上,以蛋白质残余量为指标,比较了Sevag法及TCA法(三氯乙酸法)脱除半乳甘露聚糖中蛋白质的工艺.实验结果表明,TCA法脱蛋白效果优于Sevag法,最终蛋白质残余量为1.92%,多糖损失量为5.30%.     

MALTING TECHNOLOGY AND THE PROPERTIES OF MALT: A CLUSTER ANALYSIS STUDY

A cluster analysis study of 72 malts produced from four varieties of barley malted under varying conditions has demonstrated the relative importance of the degree of steeping, germination time and temperature and kilning on the chemical and physical analysis of the malt. Seventy-two malt samples were produced from four barley varieties malted at two different degrees of steeping, two germination temperatures, two germination times, and two kilning temperatures. The malt samples were divided into 2 or 3 groups (clusters) by means of the Fuzzy Cluster Variety family of algorithms, applied to nine chemical or physical malt analyses. Each cluster could be characterized by certain mean values for the laboratory analyses and also by a particular set of technological parameters. The degree of steeping was the most important of these parameters. Laboratory analyses such as fine/coarse difference and friability were able to discriminate between a high or low degree of steeping. The cluster with a high degree of steeping could be further divided into two subclusters, with different kilning temperature. The DMS-precursor discriminated between these two kilning temperatures.