新式脱险装备配气系统

本文主要介绍了脱险装备配气系统的原理、软件和实验结果，提出了关于脱险装备配气的新概念，其采用对流配气模式，在配气过程中引入自动化控制理念，大大提高了配气效率、配气精度、简化操作、减少操作错误、增大安全系数，相对于传统的直接升压配气模式有很大的优势。     

精密流量酒精标准气体配气装置

主要介绍作者研制的一种精密流量酒精标准气体配气装置，叙述该装置的配气原理、结构、技术规格及应用实例。实验表明，该装置的配气不确定度为２％，且配制值与实测值相符。     

DP-1型动态配气仪(标准气体发生器)投产

冶金部北京钢铁研究总院研制的羰基镍标气的动态配气装置,于1984年8月6日在京通过产品鉴定,并转由江苏靖江仪器厂生产,被命名为DP-1型动态配气仪(通用型,见本期封三),经北京医学院、北京劳动保护研究所、四川省工业卫生研究所等单位试用效果良好。这种配气仪可与渗透管、扩散管或蒸发器相配用,具有稀释功能,可以配制pPb—ppM浓度水平的各种低沸点液体的标气,单组份多组份都可配,浓度连续可调,标气和零气可随意切换,浓度误差<±5％。仪器操作简便,对结构稍加改动还可进行“气—气”相配。该配气仪是我国环境监测、工业、卫生和分析计量     

配气机构的计算机模拟与凸轮型线的最优设计

一、前言 为了缩短配气凸轮的设计周期,降低成本,提高经济效益,本文用计算机模拟配气机构。在保证充气性能的前提下,自动调节配气机构各设计参数和性能参数,生成与该机构相配的凸轮型线。 经过理论分析和实例计算,证实了本文提出的计算机模拟系统,可应用于不同型号,不同性能,不同转速的内燃机的配气机构,而且均能收到显著的效果。     

气液分离器分离效果仿真研究

气液分离器是两管制热回收多联机系统中分流装置里的关键部件,其分离效果直接影响到整个空调系统的性能。为了分析气液分离器的结构并对其进行优化设计,本文基于CFD算法,建立了气液分离器仿真模型,并对仿真结果与试验结果进行了比较分析。分析结果表明,采用本文所设计的结构可以明显加强气液分离器内气液分离效果,显著增加其气侧出口干度。     

基于图像处理技术的可燃气体报警器检测装置设计

<正>本文充分利用数字图像处理技术,在动态配气系统的基础上设计了一种可燃气体报警器检测系统,符合JJG693-2011《可燃气体检测报警器检定规程》的检定项目内容,提高了工作效率及工作质量,也降低了检定工作中人为因素造成的误差出现概率,在一定程度上实现了可燃气体报警器检测工作的自动化。一、装置的基本结构及工作流程设计本文研制的可燃气体报警器检测系统主要由动态配气系统、数据采集系统及检测主控平台等3个部分构成,装置的整体示意图如图1所示。     

扩散管标准气体及其动态配气方法的研究

按照ISO6145标准，设计、研制了新型标准气体动态配气装置；实现了微机对动态配气装置的各主要参数数据的实时监控、存储和处理；定量表述了系统压力、温度等主要参数的变化对扩散管扩散率的影响及其带来的不确定度；用该动态配气装置研制了10^-6mol／mol含量范围的氮中苯系物挥发性有机物扩散管标准气体，实验表明不确定度为2％-3％；配制的标准气体与静态容量法配气装置配制的标准气体进行了比较，相对偏差在3％以内。     

SAR图像与多光谱图像融合方法研究

本文针对SAR图像分辨率高、纹理信息多、斑噪影响大，而多光谱图像光谱信息丰富、分辨率较小的特点，提出了一种SAK与多光谱图像的数据融合算法。该方法分三步进行：首先使用粗糙集理论选取图像特征，在此基础上，对特征提取后的图像进行配准，配准中采用了数理统计中近似正态分布的方法，配准精度在一个像素以内，最后采用相关性加权的方法对配准后的SAK图像与多光谱图像进行融合。融合实验以LandSat的TM图像与Radsat的SAK图像为例，实验结果表明该方法取得了较好的融合效果。     

定成份混合工质配气装置及方法

目前，国内、国外对低沸点混合工质的研究和开发十分活跃。对混合工质的热力学实验研究，首先要对工质进行定量配比。本文介绍一种为物性实验进行准确定成份配比的配气装置和配气方祛。原理是采用抽真空后充气，然后用液氮冷冻收集的方法，配气精度达到了配比质量成份相对偏差为10^-a的数量级。用间接称量法进行了质量平衡验证，证明了本装置和实验方法的可靠性和精度。该系统还可以用来进行低沸点工质中不凝结气体的排除，以提高实验样品纯度。本方法适用于配气质量少而精度要求高的场合，亦适用常规气体和液体的定量配比。     

G-M型脉管制冷机电磁阀和旋转阀配气系统的比较实验研究

配气系统作为G-M型低温制冷机的重要部件,对制冷性能有较大影响.基于1台自行研制的单级G-M型脉管制冷机,对其电磁阀配气系统和旋转阀配气系统进行了比较实验研究,重点研究了频率、时序对制冷性能的影响.实验结果表明,增大电磁阀通道数目可以在一定程度上提高压比从而提高制冷性能,但其在制冷性能方面与旋转阀相比仍存在差距.从电磁阀和旋转阀结构方面探讨了造成性能差异的主要原因.     

Electroluminescence enhancement of SiGe/Si multiple quantum wells through nanowall structures

The enhancement of light extraction from Si(0.5)Ge(0.5)/Si multiple quantum wells (MQWs) with nanowall structures fabricated by electron cyclotron resonance (ECR) plasma etching is presented. It is shown that the ECR plasma treatment does not damage the crystalline quality. At a driving current of 5.5 × 10(6)?A?m(-2), the light output intensity of the MQWs with nanowall structures shows an enhancement of about 50% compared with that of the original MQWs. In addition to the enhanced light extraction, the improved optoelectronic properties are also attributed to the strain relaxation in nanowall structures.     

InGaN/GaN multiple quantum wells grown on nonpolar facets of vertical GaN nanorod arrays

Uniform GaN nanorod arrays are grown vertically by selective area growth on (left angle bracket 0001 right angle bracket) substrates. The GaN nanorods present six nonpolar {1?100} facets, which serve as growth surfaces for InGaN-based light-emitting diode quantum well active regions. Compared to growth on the polar {0001} plane, the piezoelectric fields in the multiple quantum wells (MQWs) can be eliminated when they are grown on nonpolar planes. The capability of growing ordered GaN nanorod arrays with different rod densities is demonstrated. Light emission from InGaN/GaN MQWs grown on the nonpolar facets is investigated by photoluminescence. Local emission from MQWs grown on different regions of GaN nanorods is studied by cathodoluminescence (CL). The core-shell structure of MQWs grown on GaN nanorods is investigated by cross-sectional transmission electron microscopy in both axial and radial directions. The results show that the active MQWs are predominantly grown on nonpolar planes of GaN nanorods, consistent with the observations from CL. The results suggest that GaN nanorod arrays are suitable growth templates for efficient light-emitting diodes.     

Efficiency enhancement in a-plane InGaN/GaN light emitters with carbon nanotubes

This study investigates the coupling modes of a-plane InGaN/GaN mutiquantum wells (MQWs) with single-walled carbon nanotubes (SWCNTs). The enhancement of light emissions at resonance photon energies can be explained by the surface plasmon coupling of the MQW-SWCNT hybrid structure. The photoluminescence (PL) enhancement ratios of the indigo (2.90 eV) emission from MQWs with SWCNTs reveal three coupling modes at 2.50 eV, 2.97 eV, and 3.42 eV. In addition, the trend of the PL intensity ratios and efficiencies corresponds to that of the PL enhancement ratios. The PL efficiencies for the green (2.46 eV) and indigo (2.90 eV) emissions of SWCNT-coated MQWs are 32% and 110% better than the corresponding values of uncoated MQWs, respectively. The results show that the MQW-SWCNT hybrid structure has the potential to be applied in high-efficiency light emitters in the visible and ultraviolet range.     

White emission by self-regulated growth of InGaN/GaN quantum wells on in situ self-organized faceted n-GaN islands

The in situ self-organization of three-dimensional n-GaN islands of distinct sidewall faceting was realized by initial low V/III ratio growth under high reactor pressure followed by variations of the V/III ratio and reactor pressure. The naturally formed faceted islands with top and sidewall facets of various specific polar angles may serve as an ideal template for self-regulated growth of the InGaN/GaN multiple quantum wells (MQWs), i.e. the growth behavior is specific polar angle dependent. Further, the growth behavior and luminescence properties of the InGaN/GaN MQWs on various facets of different specific polar angles are directly compared and discussed. Tetrachromatic white emissions (blue, cyan, green, and red) from single-chip phosphor-free InGaN/GaN MQWs are realized by color tuning through island shaping, shape variations, and self-regulated growth of the InGaN/GaN MQWs.     

电子级特种气体输送系统质量控制

主要介绍应用在半导体行业电子级特种气体输送系统质量控制的要点及其涉及到的检测仪器的工作原理，结合目前行业内气体输送系统质量控制的方法做概括性介绍。     

微型节流制冷器氮气氩气超高压供气系统设计

节流制冷器的工作性能与节流工质有很大关系.设计了一套超高压的氮气和氩气供气系统,其目的是提供超过100 MPa超高压的氮气和氩气气源,并满足常规的高压气源需求,同时提供了功能先进的气体纯度在线检测、超高压力在线检测和计算机控制功能,并有单独的模块单元,可以对氮气和氩气进行适合比例的混合,或提供其它成分的节流制冷器的混合工质气体.设计有不同气瓶容积下节流制冷器的跑合实验单元,对节流制冷器的耗气性能进行测试.     

SPC分析在特种气体行业的应用

统计过程控制(Statistic process control,SPC)主要用于汽车行业及其供应商,包括半导体和特种气体行业。介绍了汽车行业质量管理体系标准IATF16949:2016的核心管理理念,即缺陷预防,持续改进,顾客满意和体系有效。重点阐述了如何用SPC对特种气体行业的关键工序的数据进行分析。应用SPC优化过程控制,可实现整个供应链中变异和浪费的减少,提高特种气体产品的质量稳定性。     

Microstructural and compositional modification of In0·53Ga0·47As/In0·52Al0·48As multiquantum wells using rapid thermal annealing process

Abstract

Quantum well intermixing of In_0·53Ga_0·47As/In_0·52Al_0·48As multiquantum wells (MQWs) in an impurity free vacancy diffusion (IFVD) mechanism was investigated to observe the intermixing aspect and the effect of defects in MQWs with regard to the microstructural aspect using transmission electron microscopy. The MQWs were grown on a GaAs (100) substrate using compositionally graded buffer layers via molecular beam epitaxy, and the MQWs were annealed at 750 and 900°C for 30 s via rapid thermal annealing for quantum well intermixing using IFVD method. In the fabricated MQWs, defects, such as stacking faults, twins and dislocations, were not generated at 750°C. The diffusion of Ga in the well layer for the quantum well intermixing started from the top well layer, because the SiO₂ layer that supplied vacancies for the quantum well intermixing was at the top of the sample. Additionally, in the same well layer, the intermixing did not show equality, because these vacancies were not supplied homogeneously. Especially, in the 900°C annealed case, many dislocations were generated from the cladding layer. These dislocations contributed to new vacancy generation sites, thus the quantum well intermixing was accelerated.     

生物质热解气化技术

生物质热解气化是农林废弃物向清洁燃气转化的关键技术,产生的合成气可替代天然气等化石燃料,实现燃气、热能和电能的供给.目前我国生物质热解气化技术经过20余年的发展,完成了民用分布式生物质燃气供应系统的示范和布局,并初步具备了规模化燃气制备和发电的产业技术基础."十二五"期间,具有显著提高燃气质量的富氧气化、蒸汽气化、甲烷化制备Bio-SNG等技术成为重要的研究方向,装备设计制造的大型化、规范化和标准化成为产业发展的必然.     

Analysis and countermeasures of natural gas development in China

Natural gas has become a transitional bridge from fossil to green and clean energy worldwide. The importance of natural gas utilization in energy structure optimization and green development is no exception for China. However, the supply of China’s natural gas limits the country’s demand with three factors. (1) China’s natural gas resource is relatively rich, but its quality is poor with deep burial depth. Therefore, the annual plateau yield of natural gas cannot be high, with an estimated value of approximately 260–270 ×10⁹ m³. (2) The demand for natural gas in China’s economic development is growing rapidly. The peak demand is estimated to be approximately 550–650 ×10⁹ m³ per year or even higher. The import volume of natural gas will soon exceed that of domestic self-produced gas. (3) Natural gas is a necessity closely related to livelihood. Particularly, a shortage in natural gas supply affects social stability. Therefore, its external dependency should be under 50% and not exceed 60%. In this study, the future situation of China’s natural gas is forecasted, and relevant countermeasures and suggestions are proposed in accordance with research on China’s natural gas resource potential, production trend, supply-demand link, and gas supply safety factors.