餐饮油烟浓度检测仪器校准方法及不确定度评定

餐饮油烟浓度检测仪具有效率高、使用简便等特点，广泛应用在环境监测中；但是，该类仪器急需建立量值溯源方法，保障监测的准确性。利用自主搭建的餐饮油烟浓度校准装置，建立了餐饮油烟检测仪器的校准方法，并对测量不确定度进行了评定。自主搭建餐饮油烟浓度校准装置中油烟浓度稳定性和均匀性偏差均小于5%,为仪器及其标准方法提供了可靠的检测条件。此外，选取2种典型中小型餐饮油烟治理设施运行工况(烟气流速：4.6 m/s, 6.2 m/s)作为测试条件，利用餐饮油烟浓度校准装置分别对2台设备进行校准测试，校准后仪器测量值与标准方法测定值的相对误差小于20%,达到餐饮油烟在线监测的要求。     

新型过滤式烧烤摊专用型油烟净化设备

通过介绍饮食业油烟的危害,阐述一种新型的过滤式烧烤摊专用型油烟净化设备的设计理念。该设备以新颖的设计构型,妥善综合了高效性、经济性、环保性与简易型等特点,具有广泛的市场前景。     

基于光散射法的餐饮油烟在线监测仪

本文在简要阐明基于光散射法的餐饮油烟在线监测仪结构的基础上,采用油烟在线监测仪对油烟、油烟颗粒物进行试验检测,测量值与标准方法的测定值进行比对.     

厨房油烟罩的二维数值仿真研究

厨房油烟罩是一种常用的厨房油烟控制设备。本文采用CFD数值模拟方法,选用二维物理模型,计算了厨房油烟罩横向中心截面上的空气流场;通过改变油烟释放速度,得出了相应的油烟控制规律;提出了一种新型的风幕式油烟罩,并分析了其油烟控制性能。     

饮食业油烟净化设备检测方法标准优化探讨

本文根据对目前普遍使用的几种油烟净化设备的检测实践,分析了《饮食业油烟净化设备技术要求及检测技术规范（试行）》（HJ/T 62-2001）中检验方法常见的问题,提出了优化建议。     

集成灶油烟净化性能测试研究

将具有油烟净化技术功能的被测试集成灶安装于集成灶油烟净化效率测试装置中,在标准试验条件下设置测试装置实现恒定平稳发烟,同时设置该集成灶在额定电压和频率下高档位运转。另外,设计加速寿命试验,在实验室环境下模拟集成灶吸排烟装置正常使用规定年限后状态,测试加速寿命后受测集成灶风量、风压值,并与受测集成灶全新状态时测得的风量、风压值对比,所得比值作为集成灶免清洗特征值,将所得测试结果与标准限值进行对比,用以评价集成灶的免清洗性能,比值越高,免清洗性能越好。     

静电消除与防护设备检测装置的研制

为防止静电防护用品在使用过程中失效并检验人员携带静电的泄放效果,对现有设备功能进行整合与扩展,并研究相关的测量方法,依据相关标准,设计了静电消除与防护设备检测装置,综合了防静电工作服、鞋、腕带、静电电压测量与释放功能,用于静电及防静电用品检测的设备,作为进入静电防护区的最后屏障,保障了设备及人身安全。     

现代空分设备的基型——分子筛净化空分流程

阐述分子筛净化空分设备的开发和应用,指出当前与可逆式空分设备的竞争焦点仍然是能耗和可靠性两个方面。节能措施是采用增压膨胀回路,改善分子筛性能,采用双层床吸附。其结构大型化,目前有立式、卧式和同心圆径流式双层床三种。由于分子筛净化空分设备具有明显的特点和优点,可以断言,现代空分设备的基型流程,必将会被分子筛净化空分流程所取代。图8表1。     

耐静电雷管的研究(四)——不用起爆药的耐静电雷管

前三报已讨论了不改变现有雷管用药的泄放式和绝缘式结构的耐静电雷管。这些结构在提高雷管的耐静电性上均有一定作用,但都难于制成耐静电性高的雷管。本报告首先分析了现有雷管装药的耐静电性能,进而提出不用现有雷管的引火药和起爆药,而以炸药为主体装药制成耐静电性能高的钝感的DDT(由燃烧转变成爆轰)型雷管,并给出了这种雷管的一些性能。     

自行车静电喷漆的几个技术问题

根据对自行车行业普遍使用的二种静电喷涂设备性能及静电涂装工艺参数的分析,提出了设备安装及吊具设计中应注意的有关问题。通过对自行车静电涂装常用溶剂性能及其对漆液电阻等施工性能影响的试验,提出了适用于静电涂装的溶剂的选择方法,同时总结了常用极性溶剂在调整漆液电阻时的用量范围。文中提出了一种比较溶剂表面张力大小的简易方法。     

障碍物对排风柜性能影响的实验研究

从排风柜面风速分布,测点风速波动等角度出发,采用实验方法研究了柜内不同大小障碍物和站立假人对排风柜性能的影响。实验结果表明:柜内放置面积率较小障碍物1和障碍物2对排风柜性能影响很小;而障碍物3和站立假人使操作口面风速分布明显不均匀,恶化了排风柜的性能;为排风柜的运行管理提供了一定的指导。     

实验室两台排风柜同时运行时性能的模拟研究

基于单台排风柜数值模拟的正确性,利用计算流体力学软件研究实验室两台排风柜在不同布置形式和布置间距时的运行性能。排风柜平行布置时,布置间距应大于0.2m;排风柜垂直布置时,布置间距对其性能影响较小;排风柜面对布置时,布置间距应大于1.2m;排风柜背对布置时,其控制气流相互干扰很小。     

Role of porosity in controlling the mechanical and impact behaviours of cement-based materials

This work deals with the influence of porosity on the tensile, the compressive and the impact behaviours of two fine cementitious mortars—one with silica fume and one without. The addition of silica fume is shown to change the pore size distribution. The mix without silica fume is characterized by porosity at the scale of the grains of fine sand (approximately 100 μm), while silica fume addition results in a more porous matrix with pore sizes of millimetre-length size. The mortar with silica fume shows a higher quasi-static compressive and flexural strength whereas the mix without silica fume is observed to be less compressible (by irreversible reduction of volume) under heavy confinement pressure (quasi-oedometric tests) and shows better ballistic performance. A numerical simulation of the impact tests employing the Krieg, Swenson and Taylor model, which accounts for both deviatoric and volumetric inelastic behaviour of the material, was undertaken using the data from quasi-oedometric tests. These calculations follow the experimental results and confirm the influence of the macroscopic porosity on the impact performance of cement-based materials.     

Long-term chloride diffusion in silica fume concrete in harsh marine climates

Supplementary cementitious materials such as silica fume are typically necessary for producing high performance concrete for marine environments in hot regions, such as the Persian Gulf. Silica fume use generally improves the strength and/or durability properties of the concrete. This paper investigates the effects of silica fume on various properties of concrete specimens that were exposed to Persian Gulf conditions. Samples were taken at the ages of 3, 9 and 36 months and analyzed to determine the chloride diffusion coefficient. The results show that partial cement replacement with up to 7.5% silica fume reduces the diffusion coefficient, whereas for higher replacement rates the diffusion coefficient does not decrease significantly. Also time-dependent chloride diffusion and compressive strength of concrete containing silica fume are investigated.     

A model predicting carbonation depth of concrete containing silica fume

Silica fume (SF) has been used since long as a mineral admixture to improve durability and produce high strength and high performance concrete. Due to the pozzolanic reaction between calcium hydroxide and silica fume, compared with ordinary Portland cement, the carbonation of concrete containing silica fume is much more complex. In this paper, based on a multi-component concept, a numerical model is built which can predict the carbonation of concrete containing silica fume. The proposed model starts with the mix proportions of concrete and considers both Portland cement hydration reaction and pozzolanic reaction. The amount of hydration products which are susceptible to carbonate, such as calcium hydroxide (CH) and calcium silicate hydrate (CSH), as well as porosity can be obtained as associated results of the proposed model during the hydration period. The influence of water-binder ratio and silica fume content on carbonation is considered. The predicted results agree well with experimental results.     

High performance concrete—An overview

It is suggested that high performance concrete is not fundamentally different from the concrete used in the past, although it usually contains fly ash, ground granulated blastfurnace slag and silica fume, as well as superplasticizer. The cost aspects of the use of silica fume are considered. The content of cementitious material is high and the water/cement ratio is low; the maximum size of aggregate is small. Although ordinary Portland cement is used, it must be compatible with a given superplasticizer; the causes of incompatibility are discussed. The distinct shrinkage behaviour of high performance concrete is considered and the reasons for an absolute necessity of wet curing are given. Some uses of high performance concrete are mentioned. A ‘prediction’ of the future of high performance concrete and of concrete in general is offered.     

微波辐射制备吸油烟复合材料及其吸附油烟性能

用微波辐射的方法制备吸油烟无纺布复合材料,讨论了微波辐照时间、合成温度、单体配比和交联剂用量对吸油烟复合材料的吸油烟性能的影响。研究结果表明,当采用微波辐照时间15min、合成反应温度为85℃、100份质量的单体(m(DMA)∶m(EHMA)=7∶3)、0.5份质量的交联剂EGDMA和5份质量的引发剂BPO,在此条件下制得吸油烟复合材料的吸油烟率最佳。与常规制备方法相比,微波辐射制备吸油烟复合材料的反应时间可由6h缩短至15min,而且其吸油烟性能也有明显的提高。     

Pore structure and chloride ion permeability of mortars containing silica fume

The addition of silica fume in concrete causes a remarkable increase in strength and a drastic reduction in chloride ion permeability. These effects may be due primarily to microstructural changes both in the cement paste phase and in the interfacial zone around aggregates. The standard method of test for rapid determination of the chloride permeability of concrete, AASHTO T 277–831, has increasingly been used to evaluate the permeability of concrete. However, for the concrete containing silica fume, the results of the AASHTO T 277–831 test, which is expressed in terms of electrical charge passed, do not necessarily reflect the real diffusion index of chloride ion through the concrete. There seems to be factors other than the pore structure which govern the results of the AASHTO T 277–831 test in the concrete containing silica fume. In this study, the effects of silica fume to reduce the chloride ion permeability of the mortar were investigated based on the results of pore size distribution measurements, X-ray diffraction analysis, SEM observations and pore solution extraction. The application of the AASHTO T 277–831 test to the evaluation of the chloride ion permeability of the concrete containing silica fume was discussed.     

Structure formation of slag ash concrete on the basis of high-calcium fly ash and silica fume

Cementless slag ash concrete may be manufactured using high-calcium fly ash and silica fume as replacements for a binder and a microfiller, and incorporating slag sand from thermal power plants (TPP) as an aggregate. This concrete consists of waste products from TPP (fly ash and slag) and ferro-alloy plants (silica fume) and contains neither natural nor artificial aggregates for lightweight and heavy concretes. Silica fume (10–20% by weight of ash) and hot water together with subsequent heat treatment of concrete products or of castin situ structures binds the excess free calcium oxide present in the ash, and thus prevents deterioration of the concrete. The processes of concrete structure formation were investigated after 24 hours, 28 days, 3 and 6 months and the physico-mechanical, deformation and special properties (frost resistance, heat conductivity, protection of reinforcement from corrosion) were studied. This concrete conforms to the Russian Federation GOST requirement for use in single, two-storey buildings. The cost of the concrete is reduced by a factor of 3 compared with that of ordinary concrete.