蜂窝-瓦楞复合纸板的面外承载及静态缓冲性能研究

通过静态压缩试验,测定了蜂窝纸板、蜂窝-瓦楞复合纸板的静态缓冲特性曲线,讨论了蜂窝-瓦楞双面复合纸板的静态压缩变形过程,并分析了复合层数和瓦楞楞型对蜂窝-瓦楞复合纸板的面外承载性能和静态缓冲性能的影响。结果表明,蜂窝-瓦楞复合纸板的面外承载能力明显低于未经复合的蜂窝纸板;蜂窝-瓦楞复合纸板在低应力阶段的缓冲性能明显优于蜂窝纸板,但在高应力阶段与蜂窝纸板的缓冲性能基本一致。     

新型环保包装"瓦楞蜂窝复合纸板制造生产线"问世

近日,浙江瑞安市红旗轻工设备厂开发的"瓦楞蜂窝复合纸板的制造生产线",在瑞安市通过省级技术成果鉴定.自动式瓦楞蜂窝复合纸板的制造生产线是利用企业自有专利技术开发的.采用瓦楞、蜂窝复合结构,显著提高了纸板的强度,其力学性能明显优于单蜂窝或单瓦楞结构的纸板.其主要功能是将再生纸全自动制成瓦楞纸蜂窝复合纸板,具有强度高、防     

新型环保包装“瓦楞蜂窝复合纸板生产线”问世

近日,浙江瑞安市红旗轻工设备厂开发的"瓦楞蜂窝复合纸板生产线",通过省级技术成果鉴定.自动式瓦楞蜂窝复合纸板的生产线是利用企业自主专利技术而开发的.采用瓦楞、蜂窝复合结构,显著提高了纸板的强度,其力学性能明显优于单蜂窝或单瓦楞结构的纸板.其主要功能是将再生纸全自动制成瓦楞蜂窝复合纸板,具有强度高、防震性能好、成本低、重量轻,以及再生纸可循环利用符合环保要求     

新型环保包装"瓦楞蜂窝复合纸板制造生产线"问世

近日,浙江瑞安市红旗轻工设备厂开发的"瓦楞蜂窝复合纸板的制造生产线",在瑞安市通过省级技术成果鉴定.自动式瓦楞蜂窝复合纸板的制造生产线是利用企业自有专利技术开发的.采用瓦楞、蜂窝复合结构,显著提高了纸板的强度,其力学性能明显优于单蜂窝或单瓦楞结构的纸板.其主要功能是将再生纸全自动制成瓦楞纸蜂窝复合纸板,具有强度高、防震性能好、成本低、重量轻,以及再生纸可循环利     

瓦楞／蜂窝复合结构纸板强度性能的试验研究

比较分析了瓦楞/蜂窝复合结构纸板的平压强度、边压强度、耐破度、戳穿强度等力学性能.结果表明,这种复合结构纸板的平压强度变化比较复杂,而它的边压强度、耐破度、戳穿强度均大于蜂窝纸板.     

自动式瓦楞蜂窝复合纸板制造生产线开发成功

日前,浙江瑞安市红旗轻工设备厂开发的“瓦楞蜂窝复合纸板制造生产线”,已通过省级技术成果鉴定。 据介绍,该生产线是利用企业自有专利技术而开发的。采用瓦楞、蜂窝复合结构,显著提高了纸板的强度,其力学性能明显优于单蜂窝或单瓦楞结构的纸板。主要功能是将再生纸全自动制成瓦楞蜂窝复合纸板,具有强度高、防     

新型绿色瓦楞蜂窝复合纸板力学性能数值模拟分析

对瓦楞蜂窝复合纸板与蜂窝纸板的边压强度及抗弯强度进行比较。利用有限元仿真技术严格控制两种纸板的材质、材料用量及尺寸均相同,将结构对两种纸板边压强度及抗弯强度的影响从众多影响因素中解耦,建立两种纸板的大尺寸数值模型试样,并采用屈曲分析方法对两种纸板的边压强度进行仿真分析,同时对比分析两种纸板的抗弯强度。分析结果表明:在材质、密度、耗材及尺寸相同的前提下,瓦楞蜂窝复合纸板的边压强度比蜂窝纸板的高出约30%;瓦楞蜂窝复合纸板的纵向及横向抗弯强度比蜂窝纸板的分别高出75%,92%,蜂窝纸板纵、横两个方向的抗弯强度基本相同。     

夹层结构纸板的力学性能测试方法概述

为了使相关人员能对夹层结构纸板的力学性能测试方法有较为全面的理解和认识,研究了瓦楞纸板、蜂窝纸板和瓦楞复合纸板的力学性能相关测试标准,阐述了各种力学性能的测试原理,分析了各测试标准之间的差异,并介绍了改进夹层结构的剪切性能测试装置的相关研究成果。通过分析可知,瓦楞纸板、蜂窝纸板和瓦楞复合纸板的不同力学性能测试标准的要求不同,且各种力学性能测试标准还需要改进和更新,3种纸板的力学性能测试需根据具体的应用环境选择合适的测试标准和方法。     

立式瓦楞复合纸板静态压缩试验与有限元分析

目的对立式瓦楞复合纸板的静态压缩过程进行试验研究和有限元分析,研究不同楞型立式瓦楞复合纸板的力学性能。方法制作A楞、AB楞、B楞等3种不同立式瓦楞复合纸板试样,进行静态压缩实验,得到其压缩应力-应变曲线;建立3种楞型的立式瓦楞复合纸板有限元模型,进行静力学分析,得到其压缩应力-应变曲线,并与实验结果进行对比分析。结果试验和有限元分析均显示立式瓦楞复合纸板的静态压缩过程与蜂窝纸板的静态压缩过程类似,包括弹性阶段、屈服阶段、平台阶段、密实化阶段,试验和有限元分析所得到的压缩应力-应变曲线相吻合。纸板的峰值应力和平台应力与楞型有关,且随着楞高的增大而减小。结论通过试验研究和有限元分析方法得到了不同楞型立式瓦楞复合纸板的静态压缩性能,对该新型材料的应用有重要参考价值。     

一种基于复合纸板的新型重型纸质包装箱

目的开发一种用于机电产品包装的新型重型纸质包装,以代替目前的木质包装箱。方法在对现有重型纸质包装研究分析的基础上,评估蜂窝纸板及各种瓦楞纸板的优劣势。采用A瓦楞/蜂窝/B瓦楞复合纸板,利用该复合纸板设计一种新型重型纸质包装,并利用Solid Works软件对2种箱板结合形式的重型纸质包装进行静载力学对比分析。结果该新型箱板结合形式能够改善箱体的应力分布状况。结论该新型重型纸质包装节约储运空间,易于成形,在一定程度上改善了箱体应力分布,是一种理想的代木包装结构形式。     

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.     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

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.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

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.……     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.