工业色谱仪仿真系统模拟出峰的数据处理

详细介绍色谱仪数据分析的理论依据,以及在PC上模拟实现输出谱峰,并根据模拟出峰给出峰形分割和组分浓度的定量计算以及柱效评价的实现方法。

模拟人体出汗的仿生皮肤

目前国内外关于仿生皮肤模型的研究主要集中在模拟人体皮肤触力感知功能、皮肤紧密接触类物质特性测试用皮肤以及模拟出汗的单层皮肤等方面,现有的研究无法真实模拟人体皮肤出汗与温度调节的功能。针对这一问题,提出了具有热源层、汗源层及表皮层的三层仿生皮肤,研究了仿生皮肤的温度及出汗控制系统。采用模糊PID控制方法实现了皮肤内核的温度控制,通过表皮温度反馈及汗源、微量柱塞泵等组成的出汗微循环系统,控制仿生皮肤出小汗、出大汗,通过汗液蒸发降温实现了表皮温度的调节。进行了内核温度控制及表皮温度调节实验,结果表明:内核温度被控制在(36.8±0.1)℃,表皮温度自稳定在(33.5±0.3)℃,仿生皮肤能够出汗将升高的表皮温度调节回(33.5±0.3)℃。研究的仿生皮肤可应用于纺织品的红外管理特性测试,模拟皮肤、纺织品及外界环境形成的微循环系统。

环境温湿度对服装热湿传递特性的影响

服装的保暖性能和透湿性能是服用性能的重要指标,与环境温度和相对湿度有关。文章利用织物模拟出汗的暖体假人,在环境温度(293±2)K,相对湿度(65±5)%和环境温度(283±2)K,相对湿度(40±5)%下,定量测试了一组服装的热湿传递特性。暖体假人在环境温度降低、相对湿度减小的情况下,服装内外存在较大的水气压力差,假人出汗量增大,蒸发散热增大,测试得到服装湿阻减小。同样,服装内外存在较大的温度差,假人干散热量也增大,实验表明服装热阻增大。

成鞋吸湿、透湿性测试仪软件研究

本文主要对成鞋吸湿、透湿性测试仪软件系统进行研究,分别对模拟出汗模块、温湿度控制模块、称重采集调控模块、结果显示模块进行了分析,并对四个模块进行了设计,设计完成了的成鞋吸湿、透湿性测试仪软件系统。

Corrosion and leaching behaviors of Sn-based alloy in simulated soil solutions

The corrosion and leaching behaviors of Sn-0.75Cu solders and joints in NaCl-Na2SO4 and NaCl-Na2SO4-Na2CO3 simulated soil solutions were investigated compared with those in NaCl solution, aiming to assess the potential risk from the electronic-waste disposed in soil. The leaching kinetics of Sn reveals that the leaching amount of Sn increases with increasing the time. The amount of Sn leached from the joint is the largest in NaCl solution.SO4^2- and CO3^2- inhibit the leaching of Sn from the joints, but accelerate that from the solders. Meanwhile, the corrosion layer of the joint in NaCl solution is more porous, and those immersed in NaCl-Na2SO4 and NaCl-Na2SO4-Na2CO3 solutions are compact. The XRD results indicate that the main corrosion products on the solders and joints surfaces are comprised of tin oxide, tin chloride and tin chloride hydroxide. The potentiodynamic polarization measurements for the solders were discussed in the simulated soil solutions.

汗湿条件下织物动态水传递的测试与分析

为了分析织物动态水传递性能,自行搭建一种具有芯吸导水功能的显性出汗模拟装置,拍照记录不同时刻织物的润湿图像,利用电子天平在线测量系统实时记录织物在吸水或蒸发过程中重量值的动态变化。利用该装置对6种面料分别进行了单层织物平面内水传递性能和2层织物层间水传递性能的动态测试。结果显示:润湿图像面积、水分在织物平面内的扩散速度、织物的吸水速度可以反映织物动态吸水与扩散性能,织物表面的水分蒸发速度可以评价织物的快干性能;织物层间水传递性能可利用模拟皮肤的水分转移率进行评价。

数字音频产品性能测试

本文通过与模拟音频产品的比较,重点讨论了数字入-模拟出工作方式的数字音频产品性能的测试方法,最后对数字入-数字出工作方式的数字音频产品性能的测试方法也简单作了介绍。

汗湿条件下幼儿睡衣面料层间水传递性能研究

为了分析在一定温度和压力下,幼儿睡衣面料中的层间水分向下传递性能,自行搭建了一种简易测试装置。通过控制恒温加热板调节模拟皮肤的温度,利用重物调节织物上方所受的压力,利用电子天平测量织物层间的含水量变化。使用该装置测试了9种幼儿睡衣面料中的水分向下传递性能、不同压力下织物层间水传递性能和不同时刻织物中的水分动态转移率,并通过聚类分析、假设检验、曲线拟合等方法进行数据分析。结果显示:各层织物含水量百分比和总体水分转移率等指标可以有效地表征所测织物的层间水传递特性,施加重物压力将对层间水传递有显著性影响,水分转移率与时间关系呈对数函数曲线特征。

Numerical simulation of micromixing effect on the reactive flow in a co-rotating twin screw extruder

To control the multicomponent reactions in extrusion, reactive-mixing flow in a co-rotating twin screw extruder was numerically studied in the present paper. Effects of initial species distribution, rotating speed and flow rate on a competitive-parallel reaction were investigated and the relationship between mixing and reactions was discussed from the view of chemical reaction engineering. The simulation results show the studied operational parameters, which determine residence time distribution, earliness of mixing and segregation degree of reactive-mixing flows, affect the local species concentration and reaction time and hence have significant influences on the reaction extent. Orthogonal test was adopted to clarify the significance of operational parameters.The analysis shows that initial species distribution and flow rate are the most important factors in the control of reaction extent, and effect of rotating speed is conditional depending on the micro-mixing status of the fluid.

Combined treatment of landfill leachate with fecal supernatant in sequencing batch reactor

A laboratory-scale sequencing batch reactor (SBR) is used to treat landfill leachate containing high concentration of ammonium nitrogen with municipal fecal supernatant. The SBR system is operated in the following sequential phases: fill period, anoxic period, aeration period, settling period, decant and idle period. The results indicated that the average removal efficiencies of COD, BOD5, TN, NH 4+-N were 93.76%, 98.28%, 84.74% and 99.21%, respectively. The average sludge removal loading rates of COD, BOD5, TN and NH 4+-N were 0.24 kg/(kg SS?d), 0.08 kg/(kg SS?d), 0.04 kg/(kg SS?d) and 0.036 kg/(kg SS?d), respectively. Highly effective simultaneous nitrification and denitrification was achieved in the SBR system. The ratio of nitrification and denitrification was 99% and 84%, respectively. There was partial NO?2 denitrification in the system.

Efficient and Accurate Simulator for Rayleigh and Rician Fading

With an improved Rayleigh fading model and a zero-mean stochastic sinusoid as the scattering and specular components respectively,a stochastic simulation model is proposed for the generation of Rayleigh and Rician fading waveforms.Compared with the existing stochastic models,the proposed simulator needs only one trial to obtain the desired statistical properties even if the number of samples is not large enough.Moreover,the proposed simulation model can directly generate multiple uncorrelated waveforms for different fading scenarios,such as single-input single-output frequency selective channels and multiple-input multiple-output channels.The performance evaluation and comparison show that the proposed simulator is efficient and accurate.

Assessment of parameters for precipitation simulation of heat treatable aluminum alloys using differential scanning calorimetry

Differential scanning calorimetry （DSC） has been used extensively to study different solid state reactions. The signals measured in DSC are associated with the growth and dissolution of different precipitates during a specific heat cycle. The time-temperature dependence of heat cycles and the corresponding heat flow evolution measured in the sample by DSC provide valuable experimental information about the phase evolution and the precipitation kinetics in the material. The thermo-kinetic computer simulation was used to predict the DSC signals of samples taken from 6xxx and 2xxx alloys. In the model, the evolution of different metastable and stable phases and the role and influence of excess quenched-in vacancies in the early stage of precipitation were taken into account. Transmission electron microscopy （TEM） and high-resolution TEM were used to verify the existence of precipitates, their size and number density at specific points of the DSC curves.

Deformation simulation of low-temperature high-speed extrusion for 6063 Al alloy

The hot compression test of 6063 Al alloy was performed on a Gleeble-1500 thermo-simulation machine, and the forming of 6063 rod cxtrudate in low-temperature high-speed extrusion was simulated with extrusion ratio of 25 on the platform of DEFORM 2D successfully. From the compression experimental results, the flow stress model of this Al alloy is obtained which could be the constitutive equation in the simulation of low-temperature high-speed extrusion process. From the numerical simulation results, there is a higher strain concentration at the entrance of the die and the exit temperature reaches up to 522 ℃ in low-temperature high-speed extrusion, which approaches to the quenching temperature of the 6063 Al alloy. The results show that the low-temperature high-speed extrusion method as a promsing one can reduce energy consumption effectively.

Modeling of Isomerization of C_8 Aromatics by Online Least Squares Support Vector Machine

The least squares support vector regression (LS-SVR) is usually used for the modeling of single output system, but it is not well suitable for the actual multi-input-multi-output system. The paper aims at the modeling of multi-output systems by LS-SVR. The multi-output LS-SVR is derived in detail. To avoid the inversion of large matrix, the recursive algorithm of the parameters is given, which makes the online algorithm of LS-SVR practical. Since the computing time increases with the number of training samples, the sparseness is studied based on the pro-jection of online LS-SVR. The residual of projection less than a threshold is omitted, so that a lot of samples are kept out of the training set and the sparseness is obtained. The standard LS-SVR, nonsparse online LS-SVR and sparse online LS-SVR with different threshold are used for modeling the isomerization of C8 aromatics. The root-mean-square-error (RMSE), number of support vectors and running time of three algorithms are compared and the result indicates that the performance of sparse online LS-SVR is more favorable.

Numerical simulation for propagation characteristics of shock wave and gas flow induced by outburst intensity

In order to analyze the propagation characteristics of shock wave and gas flow induced by outburst intensity, the governing equations of shock wave and gas flow propagation were put forward, and the numerical simulation boundary condition was obtained based on outburst characteristics. The propagation characteristics of shock wave and gas flow were simulated by Fluent software, and the simulation results were verified by experiments. The results show that air shock wave is formed due to air medium compressed by the transient high pressure gas which rapidly expands in the roadway; the shock wave and gas flow with high velocity are formed behind the shock wave front, which significantly decays due to limiting effect of the roadway wall. The attenuation degree is greater in the early stage than that in the late stage, and the velocity of gas convection transport is lower than the speed of the shock wave.The greater the outburst intensity is, the greater the pressure of the shock wave front is, and the higher the speed of the shock wave and gas flow is.

Modeling and Simulation of Enargite Bioleaching

A mathematical model for enargite bioleaching at 70℃ by Sulfolobus BC in shake-flasks has been constructed. The model included （1） the indirect leaching by Fe^3＋ and Fe^3＋ regeneration by suspended Sulfolobus, and （2） the direct leaching by the attached Sulfolobus. The model parameters were optimized using genetic algorithm （GA）. Simulations of the ferric leaching, and bioleaching processes were done using this model. The dynamic changes of the concentrations of Cu^2＋, As^3＋, As^5＋, Fe^3＋ and/or Fe^2＋, as well as ferric-arsenate precipitation were accurately predicted.

A coupled DEM and LBM model for simulation of outbursts of coal and gas

An outburst of coal and gas is a major hazard in underground coal mining. It is generally accepted that an outburst occurs when certain conditions of stress, coal gassiness and physical-mechanical properties of coal are met. Outbursting is recognized as a two-step process, i.e., initiation and development. In this paper, we present a fully-coupled solid and fluid code to model the entire process of an outburst. The deformation, failure and fracture of solid （coal） are modeled with the discrete element method, and the flow of fluid （gas and water） such as free flow and Darcy flow are modeled with the lattice Boltzmann method. These two methods are coupled in a two-way process, i.e., the solid part provides a moving boundary condition and transfers momentum to the fluid, while the fluid exerts a dragging force upon the solid. Gas desorption from coal occurs at the solid-fluid boundary, and gas diffusion is implemented in the solid code where particles are assumed to be porous. A simple 2D example to simulate the process of an outburst with the model is also presented in this paper to demonstrate the capability of the coupled model.

Analysis of SNR for Acoustic Vector Sensor Linear Array in Volume and Surface-generated Noise Fields

Acoustic vector sensor consists of pressure and particle velocity sensors,which measure the three-dimensional acoustic particle velocity,as well as the pressure at one location at the same time.By preserving the amplitude and phase information of the pressure and particle velocity,they possess a number of advantages over traditional scalar sensors.Signal-to-noise ratio (SNR) gain (which is often called array gain) is one of such advantages and is always interested by all of us.But it is not unchangeable if the spatial correlation of the noise field varies.Much more important,it is difficult to be given if the noise becomes complex.In this paper,spatial correlation of the vector field of isotropic volume-noise and surface-generated noise has been introduced briefly.Based on the results,the combined SNR output of a vector linear array is investigated and the maximum gain is given in the specified noise.Computer simulation shows that the output of one array in the same noise is not the same in different gestures.And then we find the best gesture through SNR calculation and obtain the biggest gain,which has important meaning to guide how to deploy an array in practice.We also should use the array with respect to the characteristics of the real ambient noise,especially in anisotropic noise field.

A new technology for coal and gas control based on the in situ stress distribution and the roadway layout

An auxiliary gas control technology is described that can reduce coal and gas outburst accidents when there is no existing protective coal seam and gas pre-draining is not effective.Numerical simulation methods were used to study the stress distribution ahead of the roadway face for different in situ stresses.The results from the simulation can then provide a new gas control technology.The results show that a high stress concentration,high stresses,and high displacement gradients appear ahead of the roadway face when the maximum in situ stress is aligned perpendicular to the roadway axis.The risk of gas outburst is higher when the stresses decrease rapidly over distance and when the release of more energy occurs immediately after driving the roadway.The gas outburst risk is much smaller when the in situ stress is aligned parallel to the roadway axis.During design of the coal mine most of the coal roadways should be arranged to parallel the maximum in situ stress.This will decrease the outburst risk in general and may be considered a new gas outburst prevention method.

Control of Water Supply in Pipe Networks Nonlinear Case

The paper deals with control of supply in pipe networks based on so-called Dynamic Virtual Distortion Method. Making use of the analytical network model of this installation and using presented below, the so-called Virtual Distortion Method （VDM）, the control of water supply can be performed. Minimization of supply pressure in inlets to the network, subject to inequality constraints imposed on outlet pressure （in chosen nodes） is discussed. Taking advantage of pre-computed influence vectors, the real-time control strategy can be realised with small computational effort and therefore, can be managed with use of hardware-based controllers. Non-linear constitutive relation （water flow vs. pressure head） has been assumed.