魔芋冻干粉保健食品研究

本介绍一种魔芋冻干保健食品技术。先将魔芋清洗处理后，切块，在—30℃以下快速冻结，用粉碎机进行加工成微细粉状(50μm以下)，用1％—3％石灰水溶液浸泡处理，然后再次冻结至—30℃以下，进行升华干燥成冻干粉剂。根据需要配制其他的粉剂，亦可制成以魔芋粉为主的系列魔芋粉保健食品，顺应人们减肥、保健的需求，是一种理想的多功能冻干食品。与常温破碎干燥相比，具有成粉细微，不氧化、不褪变、无异味等优点，并且配制方便、均匀，是一种先进的食品冻干工艺加工技术。     

山楂浆抽真空冻结干燥的实验研究

山楂营养丰富，食用不便，冻干加工成山楂粉，可作为食品添加剂。为保存营养成分，节能降耗，降低产品成本，开展了对山楂浆抽真空白冻结，优化干燥工艺的实验研究，给出了冻干参数对冻干速率，冻干时间，冻干成本的影响，为山楂的深加丁开辟了一条新途径。     

食品真空冻干节能技术研究

综述了国外有关食品冻干节能技术研究的状况，其中较详细地归纳与分析了降温冻结过程对节能的影响，并指出冻干与其它干燥技术组合作业是当今一种新趋势。     

冷冻干燥保存人脐血实验研究

尝试用冷冻干燥法来长期保存脐血和有核细胞,并对冻干效果进行比较分析.选用聚乙烯吡咯烷酮(PVP)、蔗糖和甘露醇等作为冻干保护剂,先将样品冻结到-38℃,随后在-30℃搁板温度下进行升华干燥,最后在15℃搁板温度下进行解吸干燥.冻干后的样品用磷酸盐缓冲液复水,然后用血细胞计数板、流式细胞仪和扫描电镜进行检测.实验结果表明:在400 g/L PVP 200 g/L蔗糖 100 g/L甘露醇作为保护剂时细胞数目恢复率最高,为(75.0±4.1)%(P＜0.01),PI染色鉴定测得单个核细胞拒染率在400 g/L PVP 200 g/L蔗糖 10%胎牛血清作为保护剂时最高,为(98.57±0.68)%(P＜0.01),CD34 细胞回收率最高为35.59%.最终确定有核细胞的冻干效果比全血的要好,初步判定冷冻干燥法保存脐血是可行的.     

食品的冷冻干燥技术

一、前言 冷冻干燥技术(简称冻干技术)是将含水物质在低温下冻结,而后使其中的水份在真空状态下直接升华。冻干技术最先用于生物物质的脱水,1930年Flosdorf开始用于食品的试验。随后,英国食品部在Aberdeen的试验工厂也进行了食品冻干的研究,他们在综合了研究成果基础上,于1961年公布了试验结果,证明冻干法用于食品加工是一种能获得优质食品的方法。紧接着,美、日、英、加等     

速冻食品冰晶体形成特性规律的研究

食品速冻技术是以食品中水分快速结晶为基础,迅速降低食品温度的加工技术。速冻技术的要求是在30分钟内通过食品最大冰晶生成带(-1～-5℃),速冻后食品中心温度必须达到-18℃,并在-18℃以下温度贮藏。食品在这样的冻结条件下,细胞间隙的游离水和细胞内的结合水、游离水能同时冻结成无数的冰晶体(冰晶粒子在100μm以下),冰晶分布与天然食品中液态水的分布极为相近,这样就不会损坏细胞组织。当食品解冻时,冰晶体融化     

深冷急冻技术冻结对虾的应用

<正>一、深冷急冻技术的意义深冷急冻是指在较短的时间间隔内将食品冻结到-60℃以下。目前在技术先进的国家中多用-196℃的液氮急冻贵重的食品,例如对虾、名贵的鱼等,以保证食品的高质量。用深冷急冻处理后的对虾,能保证它的鲜     

血管真空冷冻干燥过程的传热传质研究

本文采用无接触式称重法监测猪主动脉冷冻干燥过程,实时获取脱水速率,针对升华过程,通过采用准稳态传热模型结合脱水速率的变化来进行计算,获得升华温度、升华界面位移及传热量的变化规律.冻干参数分别设定为:预冻结温度-40 ℃、一次干燥-20℃、二次干燥10 ℃:、冻干箱压力10 Pa.结果显示,样品的平均含水量为74.24％...     

液氮冷冻甲鱼粉保健食品

<正>日本《特许公报》1986年第47505号报道,日本研究“甲鱼粉保健食品”,其制作方法是:先将甲鱼饿2天以上,然后浸渍在-196℃液氮中,经瞬间冻结后,用粉碎机粗粉碎至1cm大小,接着进行瞬间高压灭菌,再用通常的冻结干燥法干燥至     

不冻结的冷冻食品

最近国外新兴一种所谓“不冻结的冷冻食品”或“不需解冻的冷冻食品”。这是美国冷冻食品制造业用一种新开发的食品冷冻技术(半液状冷冻法)制作的冷冻食品。为将这种冷冻食品与以前的冷冻食品加以区别,特称之为冷却食品或冷硬食品。两者的区别是:普通冷冻食品是在0℉(-18℃)以下的温度管理的基础上冷藏、保管、运输和销售。而半液状冷冻法则只用20℉(-6.6℃)较高的温度管理,大大地节约了能量。且用此     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...