不同包装材料对怪味鸡丝品质的影响

目的 探讨常见包装材料对传统川菜怪味鸡丝品质的影响,为研发传统川菜怪味鸡丝包装产品进行包装材料的筛选.方法 选取PA+PE、PA+CPP、PA+PE+CPP复合包装袋,以及铝箔蒸煮袋、透明玻璃罐等5种材料对怪味鸡丝进行包装,在低温(0～4℃)条件下贮藏1～7 d,比较5种包装材料对怪味鸡丝品质的影响.结果 随着贮藏时间的增加,由质构、色差综合来看,PA+PE+CPP材质包装的鸡丝色泽与组织状态最佳;所测样品的菌落总数均呈逐渐上升趋势,得到抑菌效果优劣顺序,铝箔蒸煮袋>PA+PE+CPP复合包装袋>PA+CPP复合包装袋>PE+PA复合袋>透明玻璃罐>不包装;挥发性盐基氮以及过氧化值都呈上升趋势,包装后产品相较于不包装对照组增长的速度明显放缓,铝箔蒸煮袋与PA+PE+CPP复合包装袋包装的怪味鸡丝的保鲜效果相对较好.结论 铝箔包装袋可以更好地抑制微生物的生长繁殖和怪味鸡丝产品的氧化,可以用作怪味鸡丝产品的外包装材料.     

油炸薯条抗雾保硬（防软）包装材料研究与应用

针对油炸薯条包装储存过程膜内易产生水蒸气而导致包装薄膜雾度下降、薯条变软的现象,采用改性后的无纺布(即在聚乙烯醇中加入氯化钠、防雾剂对单一聚乙烯醇胶质进行改性,制备新的胶质,涂敷于无纺布上)为内包装材料,以聚乙烯(PE)、尼龙(PA)为外包装材料,进行密封包装。采用感官评定与机械测试相结合的方式,研究不同包装材料对油炸薯条新鲜度变化的影响。研究结果表明:以添加质量分数为2%的防雾剂改性的无纺布为内包装材料,以PE为外包装材料时,油炸薯条的保鲜效果较好。     

道路沥青包装材料及灌装技术推出

全国高技术产业化协作组织 (ＣＨＣ)推出了适用于道路沥青的生产、储运和保管部门的道路沥青包装材料及灌装技术。该包装袋采用聚烯烃共混技术研制成功 ,能在 1 2 0℃灌装 ,在 1 60℃与沥青混溶 ,不影响沥青的使用性能 ,具有足够的强度。采用交叉称重反馈调整技术 ,保证定量灌装精度。软包装袋有高强度抗老化包装外袋、耐高温复合包装袋、不同灌装温度要求的耐热包装袋等多种结构形式。有转盘传送式、直列推拉式、旋链式和移动式四种结构形式。包装袋在灌装、搬运及储存过程中不破裂、不粘连、不发脆、不泄漏 ,堆垛高度为 2米 ,露天存放一年…     

蛋糕抗菌防霉包装研究

针对蛋糕在常温储存下易腐败变质的现象,探究最适于蛋糕保鲜的抗菌防霉包装。在PE(聚乙烯)树脂中加入不同改性剂,得到SPPE(山梨酸钾等与聚丙烯、聚乙烯的复合),BPPE(苯甲酸钠等与聚丙烯、聚乙烯的复合),BCPPE(苯甲酸钠、丙酸钙等与聚丙烯、聚乙烯的复合)三种抗菌防霉薄膜,以三种抗菌防霉薄膜及PE膜为内包装材料,PA(尼龙),PP(聚丙烯)为外包装材料,两者结合,确定最适合蛋糕保鲜的内外包装材料。     

包装材料对大豆贮藏品质影响的研究

目的研究大豆在贮藏过程中包装材料对其品质变化的影响。方法采用3种包装材料(PE,PA/PE,BOPP/PA/PE)对大豆进行真空保鲜包装,监测常规储藏和不同材料包装大豆存储期间品质指标的变化,研究包装材料对大豆保鲜效果的影响。结果用薄膜包装大豆的重要品质指标均明显优于对照组,储藏至18个月时,3种包装大豆的脂肪酸值分别为20.2 mg/100 g,15.5 mg/100 g,13.7mg/100 g,而对照组大豆的脂肪酸值达到28.6 mg/100 g,已开始陈化;3种薄膜包装大豆的蛋白质溶解比率分别为71%,75.8%,74.2%,对照组的大豆蛋白质溶解比率为61.8%,高于国家规定不易存储的临界值。结论包装材料能够明显改善大豆的储藏品质,其中材料的阻隔性对大豆保鲜效果影响最显著,3种薄膜中BOPP/PA/PE的保鲜效果最优。     

复合纸桶包装火炸药的研究

用复合纸筒外包装和PET/AI/PE复合薄膜包装袋的内包装,是火炸药的一种新型包装设计,通过工艺研究试验和部队运输,长储等实际考核,证明可达到美军火药包装乙级标准,纸筒包装炸药可达美军通用标准。对包装工艺,设计和试验作了评展介绍,同时提出了改进意见。     

基于臭氧生鲜切片莲藕保鲜包装的试验研究

首先分析了臭氧抑制莲藕褐变的机理;然后用臭氧作为保鲜气体对切片莲藕保鲜包装进行试验研究.结果表明:不同包装薄膜袋、臭氧量及储藏温度对切片莲藕的褐变、失重率及感官指标有明显影响;用PA/PE膜作包装袋、储藏温度为5℃,可以有效的抑制切片莲藕呼吸强度和褐变,其切片莲藕保鲜时间长达20d.     

包装材料对樱桃番茄气调保鲜效果的影响

目的探究包装材料的阻隔性对樱桃番茄的气调保鲜效果。方法选择EHA/PE(乙烯乙烯醇共聚物、聚酰胺/聚乙烯复合膜)、PA/PE(聚酰胺/聚乙烯复合膜)、PE(聚乙烯膜)等3种薄膜气调包装樱桃番茄后于(23±2)℃温度下贮藏,无包装的樱桃番茄在同样条件下作为空白对照。定期检测包装袋内气体组分变化及感官、硬度、可溶性固形物含量、维生素C的变化情况。结果 PE组在整个贮藏过程中CO_2体积分数在5%左右,O_2的体积分数在6%~16%范围内波动,樱桃番茄处于低O_2高CO_2环境中,呼吸受到抑制,具有24 d的保鲜期。PA/PE膜、EHA/PE膜包装的樱桃番茄呼吸产生的CO_2及空气中的O_2无法透过包装膜,包装中O_2含量在第3天时便已为0,CO_2在第6天时达到30%以上,樱桃番茄处于高浓度CO_2中加速了组织腐烂,同时空白组的樱桃番茄呼吸强度和水分流失不受抑制,因此,贮藏期只有18 d。结论适宜阻隔性的材料气调包装保鲜樱桃番茄,可明显延长其保鲜期。     

油墨溶剂在食品软包装中的残留及迁移规律

目的研究油墨溶剂在食品软包装材料中的残留及迁移行为,为食品包装生产企业提供安全风险控制方面的参考。方法采用顶空气相色谱-质谱联用(HS-GC-MS)技术,对印刷油墨的挥发性溶剂在食品软包装中的残留进行定性定量分析,以检出率较高的苯类溶剂甲苯、酯类溶剂乙酸丁酯和酮类溶剂丁酮为迁移研究对象,分别以PE,PP,PET/CPP,PET/PE,OPP/CPP,PET/PA/CPP为包装材料,研究油墨溶剂在水性食品模拟液(蒸馏水)、酸性食品模拟液(体积分数为3%的乙酸)、醇性食品模拟液(体积分数为10%的乙醇)和脂肪性模拟液(正己烷)中的迁移残留行为。结果研究表明,印刷后的食品软包装材料中大部分都有苯类、酯类和酮类等有机挥发物的残留,残留溶剂在食品模拟液中迁移量的大小依次为正己烷乙醇(体积分数为10%)乙酸(体积分数为3%)蒸馏水,而且对于不同的包装材料迁移量的大小也不同。结论油墨溶剂在食品软包装材料上的残留和迁移行为,主要与环境温度、食品性质以及包装材料的性能有关。     

油炸薯条防软抗菌包装材料与技术研究

针对油炸薯条在贮藏过程中易吸收包装内外部环境的水分导致 变软、变质的现象,利用山梨酸钾（PS）、脱氢乙酸钠（SD）对聚乙烯醇（PVA）进行改性,再将改性聚乙烯醇涂布到无纺布表面得到内包装材料,并以KPET/PA/NTPE复合膜、PVDC/PE复合膜为外包装材料,对薯条进行密封包装;其后,对贮藏过程中油炸薯条的硬度、菌落总数、失重及感官评定等进行测定,从而得到最佳的包装参数。结果表明：以KPET/PA/NTPE复合膜为外包装,SD添加质量分数为3%的改性无纺布为内包装,薯条的保鲜效果最好。     

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.……     

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...     

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.     

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 ...