室内空气品质研究现状及进展

本文介绍了室内空气品质问题的由来及其危害,并介绍了的国内外有关室内空气品质的研究现状,综合讨论了室内空气品质的定义、评价指标以及影响因素,提出了改善室内空气品质的相关措施.     

室内空气品质与空调新风

本文简要介绍了家用分体空调的使用过程中对室内环境的不良影响，特别是对室内空气品质的影响，同时提出了提高室内空气品质与使用家用分体空调的矛盾，并指出其本质实际上是改善室内空气品质与节约能源的矛盾，进而提出了一些解决这一矛盾的办法，着重强调了在引入新风改善室内空气品质过程中的能量回收和提高家用分体空调的能效。其中提出了一些新的想法，有待于进一步的研究论证。     

室内空气品质及改善手段的探讨

本文主要就室内空气品质的现状以及影响因素如室外空气的污染、空调的使用、室内的装潢、办公设备现代化、人群活动作了介绍,最后从管理和技术两个层面提出了改善室内空气品质的主要手段.     

通风系统对室内空气品质的影响

本文首先阐述室内空气品质对人体的影响,并列出了衡量室内空气品质的标准,通过描述改善室内空气品质的措施,详细介绍了空调系统对商场空气品质的影响、医院的通风以及置换通风系统对空气品质的影响,对研究室内空气品质的提高有重要作用。     

室内空气品质和组合式空调机组

本文分析了造成室内空气品质恶化的原因,介绍了当前国外及香港地区采用的室内空气品质标准及相关的处理方法.同时介绍了为满足室内空气品质要求,组合式空调机组应具备的特点.实现室内空气品质改善和空调节能的有机结合.     

室内空气品质研究现状及发展趋势

本文讨论了室内空气品质这个空调领域的热门话题,介绍了人们对室内空气品质定义的认识越来越科学合理化,并介绍了国内外有关室内空气品质的研究现状,分析了影响室内空气品质的几个因素,重点对室内空气品质评价标准、方法及模式进行了阐述,本文最后提出了室内空气品质未来的研究方向.     

改善室内空气品质的探讨

分析了影响室内空气品质的室内因素及室外因素,指出了传统空调在改善室内空气品质方面存在的问题,最后提出了改善室内空气品质的措施。     

室内空气品质与组合式空调机组设计

介绍了国外著名制冷空调公司为保障室内空气品质在组合式空调机组设计方面所采取的措施。对我国组合式空调机组设计中如何考虑改善室内空气品质问题提出了建议     

喷水室净化处理空调新风

本文指出了不洁的新风是室内空气品质恶化的重要因素,介绍了室内空气品质的影响因素,阐述了对新风中有害气体净化的必要性,推荐使用喷水室净化新风中有害气体,并介绍其净化的传质机理.     

新风换气机的特性分析

分析了现代建筑室内空气污染的原因及对人体的影响;介绍了用于改善室内空气品质的新型换气装置-新风换气机的种类、原理、性能、市场分析等。     

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.     

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...     

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.     

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.     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

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.……     

Friction Stir Processing Strategies for Uniform Distribution of Reinforcement in a Surface Composite

Friction stir processing (FSP) is an important technique for preparing surface composites. Fabricating defect-free surface composites with uniform particle distribution by FSP is a challenging task. In this study, silicon carbide particles reinforced AA5083 alloy surface composites was fabricated using different FSP strategies including variation in process parameters, dual-tool processing and tool offset overlapping. Material flow of the processed material with reinforcement particles demonstrated that the distribution of particles was influenced by the stirring action of the probe as well as the extrusion of the plasticized material due to the movement of the tool. Process parameters, particularly rotational speed, showed a dominant influence on the distribution of silicon carbide particles.