Effect of different cold air intensities and their lagged effects on outpatient visits for respiratory illnesses in Handan in different seasons

本文利用2016年到2019年邯郸市气象要素和呼吸系统疾病门诊数据,分析了不同季节不同强度的冷空气过程及其对呼吸系统疾病的影响,结果显示:尽管呼吸系统疾病在冬季高发,夏季最低,但冷空气对呼吸系统疾病的影响在夏,春季最大,就诊人数分别在冷空气日后两天和五天增加18.4%和13.3%,而冬季就诊人数在冷空气日后三天仅增加3.2%.冷空气对疾病影响的滞后时间在夏,秋和冬季随冷空气强度的增加而减少,而春季的滞后时间总是很长.这些发现可为科学应对气候异常导致的人群健康风险提供针对性依据.

Stiffness Characteristics of a Basic Nonlinear Air Spring Model

This study predicts the characteristics of a compressible polytropic air spring model. A second-order nonlinear autonomous air spring model is presented. The proposed model is based on the assumption that polytropic processes occur. Isothermal and isentropic compression and expansion of the air within the spring chambers are the two scenarios that are taken into consideration. In these situations, the air inside the spring chambers compresses and expands, resulting in nonlinear spring restoring forces. The MATLAB/Simulink software environment is used to build a numerical simulation model for the dynamic behavior of the air spring. To quantify the values of the stiffnesses of the proposed models, a numerical solution is run over time for various values of the design parameters. The isentropic process case has a higher dynamic air spring stiffness than the isothermal process case, according to the results. The size of the air spring chamber and the area of the air spring piston influence the air spring stiffness in both situations. It is demonstrated that the stiffness of the air spring increases linearly with increasing piston area and decreases nonlinearly with increasing air chamber length. As long as the ratio of the vibration’s amplitude to the air spring’s chamber length is small, there is good agreement in both scenarios between the linearized model and the full nonlinear model. This implies that linear modeling is a reasonable approximation of the complete nonlinear model in this particular scenario.

Optimization of plasma-processed air(PPA)inactivation of Escherichia coli in button mushrooms for extending the shelf life by response surface methodology

The effect of plasma-processed air(PPA)treatment with different conditions(time,power andflow rate)on the inactivation of Escherichia coli(E.coli)in button mushroom was evaluated.Response surface methodology(RSM)was applied to optimize PPA treatments on the E.coli of button mushrooms.According to the response surface analysis,the optimal treatment parameters were a treatment time of 12 min,treatment power of 90 W and flow rate of 1.2 l min-1.As with verifying tests from the optimization exercise,the number of E.coli reduced by 5.27 log CFU/g at the determined optimum conditions.The scanning electronic microscopy(SEM)micrography showed that the surface of the E.coli was significantly changed under the optimized PPA treatment.Quality parameters of button mushrooms treated at the determined optimum conditions were compared with untreated samples during the storage for 12 d at 4°C?±?1°C.The PPA treatment was found to be effective in inhibiting microbes and preserving postharvest quality in button mushrooms,and these results suggested PPA treatment may provide an alternative for the sterilization of foodborne and maintaining postharvest of fruits and vegetables.

Network Aggregation Process in Multilayer Air Transportation Networks

The air transportation network, one of the common multilayer complex systems, is composed of a collection of individual airlines, and each airline corresponds to a different layer. An important question is then how many airlines are really necessary to represent the optimal structure of a multilayer air transportation system. Here we take the Chinese air transportation network （CATN） as an example to explore the nature of multiplex systems through the procedure of network aggregation. Specifically, we propose a series of structural measures to characterize the CATN from the multilayered to the aggregated network level. We show how these measures evolve during the network aggregation process in which layers are gradually merged together and find that there is an evident structural transition that happened in the aggregated network with nine randomly chosen airlines merged, where the network features and construction cost of this network are almost equivalent to those of the present CATN with twenty-two airlines under this condition. These findings could shed some light on network structure optimization and management of the Chinese air transportation system.

Component modification of steel slag in air quenching process to improve grindability

A new solution called component modification in-process was introduced to the difficult grinding of air quenching steel slag by a series of experiments. The results show that the fly ash added into the molten steel slag before air quenching can more effectively improve the slag's grindability than milltailings, which is the other modification agent tested under the same conditions. The role of fly ash is strengthened as its proportion increases, although the degree of promotion is gradually reduced. As a result of the reaction between fly ash and steel slag at high temperature, some new mineral phases and vitreous bodies with fine grindability promote the slag grinding easily. This work is helpful to making a comprehensive utilization of steel slag and maximize its economic efficiency in China.

Understanding of the Fate of Atmospheric Pollutants Using a Process Analysis Tool in a 3-D Regional Air Quality Model at a Fine Grid Scale

The process analysis is performed for August and December, 2002 using the process analysis tool embedded in the Community Multiscale Air Quality (CMAQ) modeling system at a fine horizontal grid resolution of 4-km over an area in the southeastern U.S. that is centered at North Carolina. The objectives are to qunatify the contributions of major atmospheric processes to the formation of major air pollutants and provide the insights into photochemistry that governs the fate of these pollutants at a fine grid scale. The results show that emissions provide a dominant source for gases including ammonia (NH3), nitric oxide (NO), nitrogen dioxide (NO2), and sulfur dioxide (SO2) and Particulate Matter (PM) species including fine PM (PM2.5) and its composition such as sulfate, elemental carbon, primary organic aerosol, and other inorganic fine PM in both months. While transport acts as a major sink for NH3, NO, and SO2 at most sites and PM2.5 and most of PM2.5 composition at urban sites, it provides a major source for nitric acid (HNO3) and ozone (O3) at most sites in both months, and secondary PM species in August and most PM species in December at rural and remote sites. Gas-phase chemistry serves as a source for NO2 and HNO3 but a sink for O3 at urban and suburban sites and for NO and SO2 at all sites. PM processes contribute to the formation of PM2.5 and nitrate () at the urban and suburban sites and secondary organic aerosol (SOA) at most sites in December and ammonium () in both months. They reduce formation at most sites in August and at rural and remote sites in December and the formation of PM2.5 and SOA at most sites in August. Dry deposition is an important sink for all these species in both months. The total odd oxygen (Ox) production and the total hydroxyl radical (OH) reacted are much higher at urban and suburban sites than at rural sites. Significant amounts of OH are consumed by biogenic volatile organic compounds (BVOCs) in the rural and remote areas and a combination of anthropogenic VOCs (AVOCs) and BVOCs in urban and subareas areas in August and mainly by AVOCs in December. The amount of NO2 produced by the reactions of hydroperoxy radical (HO2) is similar to that of organic peroxy radical (RO2) at all sites in August but higher than that by the reactions of RO2 inDecember. The production rate of HNO3 due to the reaction of OH with NO2 dominates in both months. The ratio of the production rates of hydrogen peroxide (H2O2) and HNO3 (PH2O2/PHNO3) is a more robust photochemical indicator than the ratios of their mixing ratios (H2O2/HNO3) and the afternoon mixing ratios of NOy in both months, and it is highly sensitive to the horizontal grid resolution in August. The use of PH2O2/PHNO3 simulated at 4-km indicates a VOC-limited O3 chemistry in urban and suburban areas in August that was not captured in previous model simulations at a coarser grid resolution.

Image Processing System for Air Classification Using Linear Discriminant Analysis

An air classifier is used in the recycling process of covered electric wire in the recycling factories, in which the covered electric wires are crushed, sieved, and classified by the air classifier, which generates wastes. In these factories, operators manually adjust the air flow rate while checking the wastes discharged from the separator outlet. However, the adjustments are basically done by trial and error, and it is difficult to do them appropriately. In this study, we tried to develop the image processing system that calculates the ratio of copper (Cu) product and polyvinyl chloride (PVC) in the wastes as a substitute for the operator’s eyes. Six colors of PVC (white, gray, green, blue, black, and red) were used in the present work. An image consists of foreground and background. An image’s regions of interest are objects (Cu particles) in its foreground. However, the particles having a color similar to the background color are buried in the background. Using the difference of two color backgrounds, we separated particles and background without dependent of background. The Otsu’ thresholding was employed to choose the threshold to maximize the degree of separation of the particles and background. The ratio of Cu to PVC pixels from mixed image was calculated by linear discriminant analysis. The error of PVC pixels resulted in zero, whereas the error of Cu pixels arose to 4.19%. Comparing the numbers of Cu and PVC pixels within the contour, the minority of the object were corrected to the majority of the object. The error of Cu pixels discriminated as PVC incorrectly became zero percent through this correction.

The Application of Air-flow to the Technological Process of Chemical Fiber

The air-flow’s states and ways acted on the technological process of chemical fiber are summed up, which includes chip drying, spinning quenching as well as airjet texturing (air texturing, tangling texturing and bulked continuous filament (BCF)),and the effect of air-flow on the process and quality of chemical fiber is studied,and the action of mechanics and heat on the bulked continuous filament are calculated.

STUDY OF THE HEAT AND HUMIDITY TRANSFER PROCESSES BETWEEN AIR AND WATER IN THE AIR WASHER

The processes of heat and humidity transfer between air and water are what to be studied mainly in the paper, we put forward some main factors which influence the processes of heat and humidity transfer in the air washer. We come to the conclusion that we can change these main factors to achieve different heat and humidity transfer processes and decide processes of heat and humidity transfer of air and water with the initial temperature of spraying water in the air washer. All these results can make things convenient for the air conditioning management.

Application, Evaluation, and Process Analysis of the US EPA’s 2002 Multiple-Pollutant Air Quality Modeling Platform

A multiple-pollutant version of CMAQ v4.6 (i.e., CMAQ-MP) has been applied by the US EPA over continental US in 2002 to demonstrate the model’s capability in reproducing the long-term trends of ambient criteria and hazardous air pollutants (CAPs and HAPs, respectively) in support of regulatory analysis for air quality management. In this study, a comprehensive model performance evaluation for the full year of 2002 is performed for the first time for CMAQ-MP using the surface networks and satellite measurements. CMAQ-MP shows a comparable and improved performance for most CAPs species as compared to an older version of CMAQ that did not treat HAPs and used older versions of national emission inventories. CMAQ-MP generally gives better performance for CAPs than for HAPs. Max 8-h ozone (O3) mixing ratios are well reproduced in the O3season. The seasonal-mean performance is fairly good for fine particulate matter (PM2.5), sulfate (SO42-), and mercury (Hg) wet deposition and worse for other CAPs and HAPs species. The reasons for the model biases may be attributed to uncertainties in emissions for some species (e.g., ammonia (NH3), elemental carbon (EC), primary organic aerosol (POA), HAPs), gas/aerosol chemistry treatments (e.g., secondary or- ganic aerosol formation, meteorology (e.g., overestimate in summer precipitation), measurements (e.g., NO3-), and the use of a coarse grid resolution. CMAQ cannot well reproduce spatial and seasonal variations of column variables except for nitrogen dioxide (NO2) and the ratio of column mass of HCHO/NO2. Possible reasons include inaccurate seasonal allocation or underestimation of emissions, inaccurate BCONs at higher altitudes, lack of model treatments such as mineral dust or plume-in-grid process, and limitations and errors in satellite data retrievals. The process analysis results show that in addition to transport, gas chemistry or aerosol/emissions play the most important roles for O3 or PM2.5, respectively. For most HAPs, emissions are important sources and cloud processes are a major sink. Simulated P H2 H O2/P HNO3 and HCHO/NO2 indicate VOC-limited chemistry in major urban areas throughout the year and in other non-urban areas in winter, but NOx-limited chemistry in most areas in summer.

Air Quality Impacts of Smallholder Oil Palm Processing in Nigeria

Air emissions during palm oil processing by smallholders are issues of public health concern demanding urgent intervention by environmentalist. In this study, six smallholder oil palm processing mills were studied inElele,Nigeria. Air emission parameters (NO2, NH3, CO, H2S, SO2, VOC), noise and meteorology (wind speed, temperature, relative humidity and pressure) were determined at three distances (10 ft,25 ftand50 ft) in both wind ward and lee ward directions from the mills covering boiling and digestion activities. The emissions from biomass were found to be significantly higher than that from fossil diesel, while noise was higher during digestion. The health implications of air emissions were discussed. The study concluded by directing attentions of regulatory agencies to monitor the activities of smallholder oil palm processing to ensure the environmental sustainability of their operations. In summary, evidence during boiling activity revealed that: · H2S ranged from - 2.400 ppm at10 ft, - 2.067 ppm at25 ftand - 0.833 ppm at50 ftfrom the mills in the wind ward direction, and - 1.167 ppm at10 ft, - 0.567 ppm at25 ftand - 0.367 ppm at50ftdistance from the mills in lee ward direction and was significantly lower during digestion. · SPM ranged from 1634 - 7853 μg/m3 at10 ft, 657 - 1110 μg/m3 at25 ftand 81 - 854 μg/m3 at50 ftfrom the mills in the wind ward direction, and 46 - 236 μg/m3 at10 ft, 44 - 120 μg/m3 at25 ftand 30 - 58 μg/m3 at50 ftfrom the mills in lee ward direction. SPM was significantly lower during digestion. · VOC ranged from 67 - 13.933 ppm at10 ft, 1.033 - 13.133 ppm at25ftand 0.500 -

Empirical Study of Classification Process for Two-stage Turbo Air Classifier in Series

The suitable process parameters for a two-stage turbo air classifier are important for obtaining the ultrafine powder that has a narrow particle-size distribution, however little has been published internationally on the classification process for the two-stage turbo air classifier in series. The influence of the process parameters of a two-stage turbo air classifier in series on classification performance is empirically studied by using aluminum oxide powders as the experimental material. The experimental results show the following: 1) When the rotor cage rotary speed of the first-stage classifier is increased from 2 300 r/min to 2 500 r/min with a constant rotor cage rotary speed of the second-stage classifier, classification precision is increased from 0.64 to 0.67. However, in this case, the final ultrafine powder yield is decreased from 79% to 74%, which means the classification precision and the final ultrafine powder yield can be regulated through adjusting the rotor cage rotary speed of the first-stage classifier. 2) When the rotor cage rotary speed of the second-stage classifier is increased from 2 500 r/min to 3 100 r/min with a constant rotor cage rotary speed of the first-stage classifier, the cut size is decreased from 13.16 μm to 8.76 μm, which means the cut size of the ultrafine powder can be regulated through adjusting the rotor cage rotary speed of the second-stage classifier. 3) When the feeding speed is increased from 35 kg/h to 50 kg/h, the 'fish-hook' effect is strengthened, which makes the ultrafine powder yield decrease. 4) To weaken the 'fish-hook' effect, the equalization of the two-stage wind speeds or the combination of a high first-stage wind speed with a low second-stage wind speed should be selected. This empirical study provides a criterion of process parameter configurations for a two-stage or multi-stage classifier in series, which offers a theoretical basis for practical production.

Optimization and Process Design Tools for Estimation of Weekly Exposure to Air Pollution Integrating Travel Patterns during Pregnancy

A growing number of international studies have highlighted that ambient air pollution exposures are related to different health outcomes. To do so, researchers need to estimate exposure levels to air pollution throughout everyday life. In the literature, the most commonly used estimate is based on home address only or taking into account, in addition, the work address. However, several studies have shown the importance of daily mobility in the estimate of exposure to air pollutants. In this context, we developed an R procedure that estimates individual exposures combining home addresses, several important places, and itineraries of the principal mobility during a week. It supplies researchers a useful tool to calculate individual daily exposition to air pollutants weighting by the time spent at each of the most frequented locations (work, shopping, residential address, etc.) and while commuting. This task requires the efficient calculation of travel time matrices or the examination of multimodal transport routes. This procedure is freely available from the Equit’Area project website: (https://www.equitarea.org). This procedure is structured in three parts: the first part is to create a network, the second allows to estimate main itineraries of the daily mobility and the last one tries to reconstitute the level of air pollution exposure. One main advantage of the tool is that the procedure can be used with different spatial scales and for any air pollutant.

大容量压缩空气储能系统空气透平工艺结构及运行特性研究

针对大容量(300MW级)蓄热式压缩空气储能系统的空气透平工作组,定量评估了高温方案(315℃)和中温方案(175℃)对透平的工艺流程结构和关键技术参数的影响,探讨了全工况下配气运行方式对透平性能的影响。研究表明,高温方案下透平工作组的工艺结构简单,但储换热系统的初投资高;高温方案的气耗率低,电电转化率高;节流+补气调节方式的高效运行区间最大。

油田采出水处理技术的研究进展

在油田开采中,采出水的直接排放会对环境造成影响,通常需要经过深度处理后再排放或者回用。而油田采出水含油量高且含有高浓度有机物和悬浮物,处理难度大。水质特性、处理技术以及处理设备等都会对处理效果产生直接影响,因此,有必要对上述问题进行深入研究。本文对现有研究中油田采出水的水质特性、新型的膜分离技术以及气浮工艺进行了总结,分析了各类处理技术研究现状,并对今后发展趋势进行了展望。

Low-Power Operational Amplifier for Real-Time Signal Processing System of Micro Air Vehicle

A low-power complementary metal oxide semiconductor（CMOS） operational amplifier （op-amp） for real-time signal processing of micro air vehicle （MAV） is designed in this paper.Traditional folded cascode architecture with positive channel metal oxide semiconductor（PMOS） differential input transistors and sub-threshold technology are applied under the low supply voltage.Simulation results show that this amplifier has significantly low power,while maintaining almost the same gain,bandwidth and other key performances.The power required is only 0.12 mW,which is applicable to low-power and low-voltage real-time signal acquisition and processing system.

中国极端天气气候研究——“地球系统与全球变化”重点专项项目简介及最新进展

全球变暖背景下,极端天气气候事件频发,并表现出群发性、持续性、复合性等特点,不可预测性增加;持续性强降水、极端低温、复合型极端高温干旱、群发性热浪和台风等极端天气气候事件对我国经济社会和可持续发展影响巨大。然而,上述极端天气气候事件的新特征、关键过程和机理尚不完全清楚,重大极端事件的预报预测水平亟待提升。文章首先简要介绍“地球系统与全球变化”重点专项项目“中国极端天气气候事件的形成机理及其预测和归因”的基本情况。项目拟在分析全球变化背景下对我国造成重大影响的极端天气气候事件新特征的基础上,深入研究多尺度海-陆-气耦合过程影响极端天气气候事件的机理,挖掘极端天气气候事件次季节-季节预测的前兆信号;发展动力与物理统计相结合的极端事件预测新方法,研制针对中国极端事件的新一代高分辨率数值预报与检测归因系统。文章重点总结了自2022年12月项目立项至今取得的最新研究成果和进展。

马钢2×380m^(2)烧结机节能减排实践

为进一步适应烧结生产优质、降耗、减排的发展的需求,马钢2×380m^(2)烧结机采取了一系列提质降耗技术措施。通过持续优化厚料层烧结生产经济潜力;降低固体燃耗;点火炉升级改造、带冷机改环冷机、烧结机漏风治理、大型风机变频技术等多项节能新技术的应用以及创新管理,在烧结矿质量以及节能降耗方面取得了显著改善效果,工序能耗由55 kgce/t下降至47kgce/t水平。同时对当前2×380m^(2)烧结机烧结高效、低耗生产存在的问题提出了改进方向,以进一步促进节能减排工作的持续发展。

云南冬季强降温过程冷空气路径及大气环流差异

基于云南125个测站日平均气温数据,判定了1961—2020年云南冬季95次强降温过程的4种冷空气路径,对比分析了不同路径冷空气对云南降温的影响及大气环流差异.结果表明,东北路径冷空气对云南降温幅度影响最剧烈、影响空间范围最广;偏东路径出现频率最高,偏东路径和偏北路径在降温幅度和影响范围上较为接近;东南路径降温幅度和影响范围最弱,出现频率最低.超前强降温日2 d时,东北路径欧亚大陆500 hPa位势高度场上正高度距平异常区域强度和面积、700 hPa反气旋距平环流强度和西伯利亚高压均为最强,东南路径最弱,偏东路径和偏北路径介于前二者之间.东北路径500 hPa上东亚槽横槽转竖特征最明显,偏东路径和偏北路径东亚槽槽底南压加深,但转竖特征不及东北路径明显;东南路径东亚槽底部较宽广;东北路径副高呈块状面积最小,其它3种路径副高则呈带状,偏东路径副高面积最大.700 hPa上东北路径和偏东路径在日本附近有较强海平面气压负距平发展,朝鲜半岛气旋距平环流较强,其西侧较强的偏北气流引导冷空气进入云南;东南路径和偏北路径在朝鲜半岛气旋距平环流及其西侧的偏北气流较弱.在200 hPa纬向风距平场上,东北路径急流轴附近正负距平区强度最强,偏东路径沿急流轴距平分布为西正东负;东南路径正负距平区强度最弱,负距平区主要分布在急流轴北侧,偏北路径负距平区分布在急流轴南北两侧.

涂装车间加湿、降温、除尘原理及应用

主要介绍了涂装车间加湿、降温、除尘原理及应用,涂装车间喷漆室、人工操作室体、员工休息区、空调系统均需要用到相关的技术,在策划阶段提前确定各工艺段的温度、湿度、防尘等级,后续设计过程中准确计算和设备选型。