Kinematic Characteristics and Thermophoretic Deposition of Inhalable Particles in Turbulent Duct Flow

The kinematical characteristics and thermophoretic deposition of inhalable particles with the diameters of 0-2.5μm （hereafter referred to as PM2.5） suspended in turbulent air flow in a rectangular duct with temperature distribution were experimentally studied. Particle dynamics analyzer （PDA） was used for the on-line measurement of particle motion and particle concentration distribution in the cross-sections of the duct. The influences of the parameters such as the ratio of the bulk air temperature to the cold wall temperature and the air flow rate in the duct on the kinematical characteristics and the deposition efficiencies of PM2.5 were investigated. The experimental re- sults show that the deposition efficiencies of PM2.5 mainly depend on the temperature difference between the air and the cold wail, wffile the air flow rate and the particlecon^centration almost affect hardly tile clep0si-tion-effi ciency. The radial force thermophoresis to push PM2.5 to the cold wail is found the key factor for PM2.5 deposition.Based on the experimental results, an empirical modified Romay correlation for the calculation of thermophoretic deposition efficiency of PM2.5 is presenlext. The empirical correlation agrees reasonably well with the experimental data.

Variation Characteristics of Mass Concentration of Inhalable Particles in Qingdao, China

The geographical condition of Qingdao, China is relatively special;the transport of various inland pollutants, the emissions of marine aerosol and local pollutants will have an impact on the changes of atmospheric aerosol concentration. By using the stability classification method, trajectory clustering analysis and the NOAA HYSPLIT model, the seasonal distribution characteristics of atmospheric inhalable particulate matter concentration in Qingdao, China and its relationship with meteorological conditions, mixed layer height, and the seasonal characteristics of Qingdao pollutant transport were analyzed. The results show that the variation trends of PM2.5 and PM10 were about the same, and there are obvious seasonal differences, which are high in winter and spring, and low in summer and autumn. The concentration of inhalable particulate matter has a negative correlation with temperature, wind speed and relative humidity. The concentration of inhalable particulate matter is distinct in different relative humidity ranges. When the wind speed is less than 3 - 4 m/s, there are more inhalable particles, while the mass concentration shows obvious reduction with the wind speed more than 4 m/s. There is a significant negative correlation between the mass concentration of pollutants and the daily maximum mixed layer height. The larger the concentration of pollutants, the smaller the thickness of the daily largest mixed layer. Conversely, the smaller the mass concentration of pollutants, the larger the thickness of the daily largest mixed layer. The pollutant transport in Qingdao has obvious seasonal characteristics. The air mass in spring, autumn and winter is mainly medium-long distance transport from Mongolia and southern Russia, and medium-short distance transport from Inner Mongolia and northeast of China. The source of air masses in summer is mainly transported from the eastern and sea areas.

基于SEM IP和部分重配置的SRAM型FPGA单粒子故障注入

SEM IP(Soft Error Mitigation软错误缓解核)是对SRAM FPGA设计进行单粒子故障注入的一种有效方法.然而由于目标设计与SEM IP部分随机布局布线在一块芯片上,导致进行故障注入时很有可能会打翻SEM IP所使用的配置寄存器而导致故障注入停止工作,同时对于目标设计失效率统计不准确.为解决这一问题,基于SEM IP和部分重配置技术开发了一套单粒子故障注入原型系统用于单粒子故障注入实验.该方法将SEM IP和目标设计布局布线到芯片的不同区域,能够只对目标设计所在区域进行故障注入并且不中断目标设计运行,并且在发生不可纠正错误后对目标设计所在区域进行部分重新配置,配置数据更少,用时更短,系统故障的注入效率大大提高,提高对于目标设计软错误失效率估计的准确性.

A two-stage CO-PSO minimum structure inversion using CUDA for extracting IP information from MT data

The study of induced polarization （IP） information extraction from magnetotelluric （MT） sounding data is of great and practical significance to the exploitation of deep mineral, oil and gas resources. The linear inversion method, which has been given priority in previous research on the IP information extraction method, has three main problems as follows： 1） dependency on the initial model, 2） easily falling into the local minimum, and 3） serious non-uniqueness of solutions. Taking the nonlinearity and nonconvexity of IP information extraction into consideration, a two-stage CO-PSO minimum structure inversion method using compute unified distributed architecture （CUDA） is proposed. On one hand, a novel Cauchy oscillation particle swarm optimization （CO-PSO） algorithm is applied to extract nonlinear IP information from MT sounding data, which is implemented as a parallel algorithm within CUDA computing architecture; on the other hand, the impact of the polarizability on the observation data is strengthened by introducing a second stage inversion process, and the regularization parameter is applied in the fitness function of PSO algorithm to solve the problem of multi-solution in inversion. The inversion simulation results of polarization layers in different strata of various geoelectric models show that the smooth models of resistivity and IP parameters can be obtained by the proposed algorithm, the results of which are relatively stable and accurate. The experiment results added with noise indicate that this method is robust to Gaussian white noise. Compared with the traditional PSO and GA algorithm, the proposed algorithm has more efficiency and better inversion results.

Preparation of Ultra-fine Salbutamol Sulfate Particles by Reactive Precipitation and Characterization of Dry Powder Inhalant

The preparation of ultra-fine particles of salbutamol sulphate （SS） was accomplished with a reactive precipitation pathway, in which salbutamol and sulphuric acid were Used as reactants with the solvents of ethanol.The effects of sulphuric acid concentration, reaction temperature, stirring rate, and reaction time onthesize of the particle were investigated. A binary mixture composed of lactose and SS was prepared to evaluate SS. The results showed that ultra-fine SS particles with controlled diameters ranging between 3 μm and 0.8 μm and with a narrow distribution could be achieved. The morphology consisting of clubbed particles wassuccess.fully obtained. The purity of the particles reached above 98% with-UV detection. The dose- of dry powder inhalation was obtained by blending the particles with recrystallized lactose, which acted as a carrier. The deposition quantity of the drug in breathing tract was estimated using a twin imPinger apparatus. Compared with the Shapuer powder （purchased in the market）, the results showed that SS_particles had more quantifies.subsided in simulative lung.. _

Threshold friction velocity influenced by soil particle size within the Columbia Plateau, northwestern United States

Wind erosion is a geomorphic process in arid and semi-arid areas and has substantial implications for regional climate and desertification.In the Columbia Plateau of northwestern United States,the emissions from fine particles of loessial soils often contribute to the exceedance of inhalable particulate matter(PM)with an aerodynamic diameter of 10μm or less(PM10)according to the air quality standards.However,little is known about the threshold friction velocity(TFV)for particles of different sizes that comprise these soils.In this study,soil samples of two representative soil types(Warden sandy loam and Ritzville silt loam)collected from the Columbia Plateau were sieved to seven particle size fractions,and an experiment was then conducted to determine the relationship between TFV and particle size fraction.The results revealed that soil particle size significantly affected the initiation of soil movement and TFV;TFV ranged 0.304-0.844 and 0.249-0.739 m/s for different particle size fractions of Ritzville silt loam and Warden sandy loam,respectively.PM10 and total suspended particulates(TSP)emissions from a bed of 63-90μm soil particles were markedly higher for Warden sandy loam than for Ritzville silt loam.Together with the lower TFV of Warden sandy loam,dust emissions from fine particles(<100μm in diameter)of Warden sandy loam thus may be a main contributor to dust in the region's atmosphere,since the PM10 emissions from the soil erosion surfaces and its ensuing suspension within the atmosphere constitute an essential process of soil erosion in the Columbia Plateau.Developing and implementing strategic land management practices on sandy loam soils is therefore necessary to control dust emissions in the Columbia Plateau.

基于PSO和共轭梯度法的MIP路由优化方案

针对移动IP网络中三角路由算法效率不高,导致移动网络性能难以达到最优的问题,提出了一种基于PSO和共轭梯度法的移动IP路由优化方案。首先利用"粒子"来取代网络节点中的路由选择表,将IP网络和粒子群算法联系起来,研究将粒子群算法用于求解移动IP路由选择当中的最短路径,针对粒子群算法早熟收敛和局部搜索能力不足的缺陷,引入局部搜索能力强的共轭梯度算法对其进行优化,从而有效提高找出移动IP最短路由的速度;仿真结果表明了该算法的有效性。

Numerical simulation of particle deposition in obstructive human airways

To investigate airflow pattern and its impact on particle deposition, finite-volume based computational fluid dynamics （CFD） simulations were conducted in the diseased triple-bifitrcation airways. Computations were carried out for twenty Reynolds numbers ranging from 100 to 2 000 in the step of 100. Particles in the size range of 1-10 μm were conducted. Two particle deposition mechanisms （gravitational sedimentation and inertial impaction） were considered. The results indicate that there are strong relationship between airflow structures and particle deposition patterns. Deposition efficiency is different for different particles in the whole range of the respiratory rates. Particles in different sizes can deposit at different sites. Smaller particles can be uniformly deposited at the inside wall of the considered model. Larger particles can be mainly deposited in the proximal bifurcations. Deposition fraction varies a lot for different inlet Reynolds numbers. For lower Reynolds numbers, deposition fraction is relatively small and varies a little with varying the diameters. For Reynolds number to target the aerosols at the specific site. higher Reynolds numbers, there is a most efficient diameter for each

Agglomeration rate and action forces between atomized particles of agglomerator and inhaled-particles from coal combustion

In order to remove efficiently haled-particles emissions from coal combustions, a new way was used to put forward the process of agglomeration and the atomization was produced by the nozzle and then sprayed into the flue before precipitation devices of power station boiler in order to make inhaled-particles agglomerate into bigger particles, which can be easily removed but not change existing running conditions of boiler. According to this idea, a model is set up to study agglomeration rate and effect forces between fly ash inhaled-particles and atomized agglomerator particles. The developed agglomeration rate was expressed by relative particle number decreasing speed per unit volume. The result showed that viscosity force and flow resistance force give main influences on agglomeration effect of inhaled-particles, while springiness force and gravity have little effect on agglomeration effect of theirs. Factors influencing the agglomeration rate and effect forces are studied, including agglomerator concentration, agglomerator flux and agglomerator density, atomized-particles diameters and inhaled-particles diameter and so on.

Preparation of slab-shaped lactose carrier particles for dry powder inhalers by air jet milling

Dry powder inhalers are often formulated by attaching micronized drug particles onto carrier particles, which are generally lactose. In this study, commercially available lactose was air jet milled to produce unique slab-like coarse carrier particles, which have larger and rougher surfaces compared to other commercially available lactose. Two key processing factors, i.e.,classifier speed and jet milling pressure, were systematically investigated. The largest fraction of slab-like particles in the resulting powder was obtained at a classifier speed of 3000 rpm.The slab-like coarse carrier particles are expected to exhibit superior performance than commercial lactose due to their unique surface properties.

基于约束知识的IP-MCMC-PF目标跟踪方法研究

针对粒子滤波算法在有干扰的目标跟踪中可能出现的粒子多样性减少和精度下降等问题,研究并实现了一种新的基于约束知识的IP-MCMC-PF目标跟踪方法。该方法首先通过约束知识提高粒子预测的准确性,并通过多链并行的IP-MCMC方法提高粒子的多样性,有效地解决粒子退化问题;在此基础上通过PN学习算法在线更新抽样粒子的抽样分布和检测器的训练样本,实现目标跟踪算法的在线学习,有效提高了复杂背景下目标跟踪的准确度和自适应性。实验结果表明,该方法在遮挡、形变、光照变化等多种干扰的情形下都具有很好的跟踪效果。

Inversion of IP-Affected TEM Responses and Its Application in High Polarization Area

The transient electromagnetic(TEM)responses measured in areas with highly pola-rizable media commonly show induced polarization(IP)effects,which poses difficulties to the TEM data interpretation and inversion with conventional methods.When present,the IP effects break the monotony in TEM decay curves and can even cause sign reversals,and lead to the singularity and non-monotony of inversion method.It is therefore important to take the IP effects into account when processing those TEM data.In this paper,a new inversion method is developed to invert TEM data with IP effects.The Cole-Cole model was introduced to the forward modeling solver so that the IP effects can be accurately calculated.The regularization terms were adapted to the objective function and a global optimization method,the particle swarm optimization algorithm,was used to solve the optimization problem,which weakened the singularity and non-monotony of the inversion greatly.Field data were collected in Wulong gold mine where IP effects were detected.The data were in-verted using the method developed in this paper,and the inversion results were able to identify the depth extension of NO.163 ore-bearing quartz veins and their associated fine-grained diorite veins.The global inversion method in this paper primarily solved the inversion problem of IP-affected TEM responses,and recovered the polarization parameters,which can be used as an aid to the geo-logical interpretation.

SECURE STEGANOGRAPHY BASED ON BINARY PARTICLE SWARM OPTIMIZATION

The objective of steganography is to hide message securely in cover objects for secret communication.How to design a secure steganographic algorithm is still major challenge in this re-search field.In this letter,developing secure steganography is formulated as solving a constrained IP(Integer Programming) problem,which takes the relative entropy of cover and stego distributions as the objective function.Furthermore,a novel method is introduced based on BPSO(Binary Particle Swarm Optimization) for achieving the optimal solution of this programming problem.Experimental results show that the proposed method can achieve excellent performance on preserving neighboring co-occurrence features for JPEG steganography.

玉屏风颗粒联合沙美特罗替卡松粉雾化吸入对急性发作期哮喘患儿IP-10、免疫功能及相关细胞因子的影响

目的探讨玉屏风颗粒联合沙美特罗替卡松粉雾化吸入对急性发作期哮喘患儿干扰素诱导蛋白10(IP-10)、免疫功能及相关细胞因子的影响。方法选择2017年1月至2018年12月间我院收治的急性发作期哮喘患儿144例进行研究,随机分为观察组和对照组各72例。两组均进行常规西医治疗,然后对照组给予沙美特罗替卡松粉雾化吸入治疗,观察组给予玉屏风颗粒联合沙美特罗替卡松粉雾化吸入治疗,均治疗8周。观察两组患儿治疗前后的哮喘症状评分、IP-10、肺功能、T淋巴细胞亚群(CD4+、CD8+、CD4+/CD8+)、特异性免疫球蛋白E(IgE)、组胺H4R、白介素4(IL-4)、白介素27(L-27)、y干扰素(INF-y)水平变化情况,以及不良反应情况。结果治疗后,观察组的日间哮喘症状评分、夜间哮喘症状评分、IP-10、CD4+、CD4+/CD8+、IgE、H4RmRNA及IL-4水平低于对照组(P<0.05);而CD8+、IL-27、INF-y、FVC、PEF、FEV1/FVC水平高于对照组(P<0.05)。两组患儿的不良反应发生率差异无统计学意义(P>0.05)。结论玉屏风颗粒联合沙美特罗替卡松粉雾化吸入治疗可有效减轻急性发作期哮喘患儿的临床症状,其机制可能与改善患儿免疫功能、肺功能,降低H4RmRNA、IP-10表达水平有关。

Analysis of Components in Indoor Particles and Pollution Characteristics

Atmospheric particulate samples were collected from four densely populated places in a university,and then the concentration levels of indoor particulates were analyzed.Water-soluble cations and anions in the indoor particles were analyzed through ultrasonic extraction and ion chromatography(IC),and total organic carbon(TOC)content was analyzed by using a TOC analyzer.Organic compounds in the indoor particles were analyzed through ultrasonic extraction and GC-MS.The results showed that among the water-soluble ions,the mass concentration of SO2-4in indoor particles was the highest,so it was the main contributor of water-soluble anions,indicating that combustion of fossil fuels and industrial discharge were main sources of indoor particles at the four sampling points.Water-soluble organic carbon was the main component of water-soluble carbon in indoor particles.Among the four sampling points,the mass concentrations of the 18 organic compounds except for glycerol and phthalic acid were the highest in the cafeteria,so organic components in indoor atmospheric particles were mainly from food sources.

The effect of ethanol on the habit and in vitro aerodynamic results of dry powder inhalation formulations containing ciprofloxacin hydrochloride

In the case of dry powder inhalation systems(DPIs),the development of carrierfree formulations has gained increased attention.Thereby,spray-drying is a promising technology and is widely used to produce carrier-free DPIs.Numerous works have been published about the co-spray-drying of active ingredients with various solid excipients and their effect on the physicochemical characteristics and aerodynamic properties of the formulations.However,only a few studies have been reported about the role of the solvents used in the stock solutions of spray-dried formulations.In the present work,DPI microcomposites containing ciprofloxacin hydrochloride were prepared by spray-drying in the presence of different ethanol concentrations.The work expresses the roughness,depth and width of the dimples for particle size as a novel calculation possibility,and as a correlation between the MMAD/D_(0.5)ratio and correlating it with cohesion work,these new terms and correlations have not been published–to the best of our knowledge–which has resulted in gap-filling findings.As a result,different proportions of solvent mixtures could be interpreted and placed in a new perspective,in which the influence of different concentrations of ethanol on the habit of the DPI formulations,and thus on in vitro aerodynamic results.Based on these,it became clear why we obtained the best in vitro aerodynamic results for DPI formulation containing 30%ethanol in the stock solution.

The effects of surface morphology on the aerosol performance of spray-dried particles within HFA 134a based metered dose formulations

The aim of this study was to produce fine particles with different corrugated degree of surface by spray-drying and to investigate the effect of surface morphology on in vitro aerosol performance of the particles within HFA 134a based metered dose formulations.Compositions of rizatriptan and scutellarin were spray-dried using different spray-drying parameters,and particles were suspended within HFA 134a.The surface morphology were determined using scanning electron microscopy(SEM),while the aerodynamic performance of MDIs was evaluated using a next generation pharmaceutical impactor.The surface morphology of spraydried particles could vary from smooth to moderately corrugated,and to raisin-like depending upon spray-drying parameters and preparation compositions.In general,increasing inlet temperature,decreasing feed concentration and/or adding leucine to the feed solution tended to increase the corrugated degree of particle surface.Deposition results indicated that raisinlike particle based MDIs for all compositions of the two drugs produced significantly better aerodynamic performance in terms of fine particle fractions and mass median aerodynamic diameters relative to the formulations of the corresponding smooth or slightly corrugated particles when the particle compositions were the same.The present results demonstrated that wrinkled particles increased fine particle fractions within surfactant-free MDI formulations.

Drug/polymer nanoparticles prepared using unique spray nozzles and recent progress of inhaled formulation

Inhaled formulations are promising for pulmonary and systemic non-pulmonary diseases.Functional engineered particles including drugs and drug-loaded nanocarriers have been anticipated because they can improve drug delivery efficacy against target sites in the lungs or blood.In this review,unique spray nozzles(e.g.,four-fluid spray nozzle and twosolution mixing type nozzle)for the preparation of nanocomposite particles which mean microparticles containing drug nanoparticles are described.These nozzles can produce nanocomposite particles in one-step and their spray drying system is suitable for scalingup.Nanocomposite particles are useful in improving drug absorption and delivery efficacy against alveolar macrophages.In addition,recent studies on several pulmonary diseases(tuberculosis,lung cancer,cystic fibrosis,pneumonia,vaccine and others)and related inhaled formulations were also reviewed.

Experimental study and numerical simulation of gas/particle flow in tunneling of mine

Respiration particles can be collected into a dust catcher by an inside inhalingand outside pressing particle collector. The work environment of the grab operator in tunneling mining was improved when a dust catcher is placed before the working face of thegrab operator. The particle movement was affected by the gas flow. The flow field insideand outside the dust collector was simulated. The effect of the operating parameter wasanalyzed. The numerical results show a good approach to predict the gas flow and particledistribution in the inside and outside of the particle collector.

基于混合粒子群优化的移动IP路由选择

针对移动IP网络中,现有三角路由算法效率不高,导致移动网络性能难以达到最优的问题,提出了一种将模拟退火算法和粒子群算法结合使用的基于混合粒子群的移动IP路由算法,仿真结果表明了该算法的有效性。