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121.
目的 研究对火工品适用的温湿度加速模型,以及加速系数计算程序,获取准确的温湿度加速系数外推公式.方法 通过分析国内外使用的各种双因素加速模型的适用性,确定火工品适用的温湿度加速模型,采用免费自由的开源统计分析软件——R软件,对通过加速试验获取的某点火头2种温湿度加速条件下的试验数据,进行单组数据拟合和多组数据拟合两种温湿度加速老化算法的开发,并且对2种算法、3种寿命分布下寿命外推的准确性进行对比分析.结果 确定了Peck模型适合用于火工品的温湿度加速模型,获取了某电点火头对应的温湿度加速系数和湿度项反应速率常数.结论 基于多组数据拟合的温湿度加速老化算法,比基于单组数据拟合的温湿度加速老化算法对试验数据的兼容性好.3种寿命分布中,Weibull分布的加速系数计算结果最保守. 相似文献
122.
介绍了江苏省重污染天气监测预报预警系统以及大气重污染预警会商流程,将2015年13个地级市的模式预报、人工预报结果分别与实际观测值进行比较。结果表明:人工预报更准确,PM_(2.5)日均值、臭氧日最大8 h平均值、AQI 3个指标人工预报和实况的相关性分别比模式预报高出12.8%、0.3%、11.4%,平均标准误差(MNE)分别低20.7%、3.1%、23.1%。依据国家空气质量预报技术指南评分办法,对各市2015年全年空气质量级别为"良"时进行评分。通过开展07∶00预报更新,使2015年上半年空气质量预报级别得分平均提高了0.9分,全年级别得分平均提高了2.6分;通过改进模式预报参数,使PM_(2.5)日均预报值、臭氧日最大8 h平均预报值、AQI预报值和实际观测值的相关性比上年同期分别提高26.0%、5.0%、33.9%,MNE分别降低3.6%、31.3%、7.6%。 相似文献
123.
制备了钾改性正硅酸锂(K-Li4SiO4),并对其进行了自活化,考察了活化后K-Li4SiO4吸附剂在不同温度和CO2浓度气氛中吸附CO2的性能及动力学行为。总体而言,吸附剂的CO2吸附能力随着温度的升高、CO2浓度的增加而提升。在700℃、100%体积分数CO2气氛中吸附剂的吸附量最大,可达7.9 mmol/g,吸附剂的利用率为95.2%。利用双指数模型能够很好地描述吸附剂在各个温度以及各个CO2浓度气氛下的CO2吸附过程。吸附活化能随着CO2气氛浓度的升高而降低,CO2体积分数为20%,50%,100%时的吸附活化能分别为26448,14035,6178 J/mol。 相似文献
124.
本文选取中国280个地级市2009—2018年的面板数据为研究样本,探究城市蔓延与雾霾污染之间的作用机制。以私人交通为门槛变量,考察城市蔓延对雾霾污染的门槛效应。研究结果表明:(1)城市蔓延对雾霾污染的影响呈现出先降后升的U形曲线特点;(2)私人交通对雾霾污染的影响表现为倒U形的曲线特征,即随着私人交通发展水平的提高,雾霾污染呈现先增后减的趋势;(3)城市蔓延对雾霾污染的影响存在双重门槛效应,当私人交通的门槛值小于第一个门槛值(e11.6130=110 525辆)时,城市蔓延会加剧雾霾污染;当私人交通的门槛值介于第一个门槛值和第二个门槛值(e12.2473=208 417辆)之间时,城市蔓延对雾霾污染的影响系数为正,但未通过显著性检验;当私人交通跨过第二个门槛值时,城市蔓延水平的提高有助于抑制雾霾污染。研究城市蔓延、私人交通与雾霾污染这三者之间的关系对于促进城市的健康可持续发展具有重要的意义。 相似文献
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128.
Refractory dissolved organic matter (DOM) from landfill leachate treatment plant was with high dissolved organic carbon (DOC) content. An aminated polymeric adsorbent NDA-8 with tertiary amino groups and sufficient mesopore was synthesized, which exhibited high adsorption capacity to the DOM (raw water after coagulation). Resin NDA-8 performed better in the uptake of the DOM than resin DAX-8 and A100. Electrostatic attraction was considered as the decisive interaction between the adsorbent and adsorbate. Special attention was paid to the correlation between porous structure and adsorption capacity. The mesopore of NDA-8 played a crucial role during uptake of the DOM. In general, resin in chloride form performed a higher removal rate of DOC. According to the column adsorption test, total adsorption capacity of NDA-8 was calculated to 52.28 mg DOC/mL wet resin. 0.2 mol/L sodium hydroxide solution could regenerate the adsorbent efficiently. 相似文献
129.
Development and application of a two-dimensional water quality model for theDaqinghe River Mouth of the Dianchi Lake 总被引:1,自引:1,他引:0
Water quality models are important tools to support the optimization of aquatic ecosystem rehabilitation programs and assess their efficiency. Basing on the flow conditions of the Daqinghe River Mouth of the Dianchi Lake, China, two-dimensional water quality model was developed in the research. The hydrodynamics module was numerically solved by the alternating direction iteration (ADI) method. The parameters of the water quality module were obtained through the in situ experiments and the lab analyses that were conducted from 2006 to 2007. The model was calibrated and verified by the observation data in 2007. Among the four modelled key variables that were water level, CODcr, NH3-N and PO4-P, the minimum value of the coefficient of determination (CoD) was 0.69, which mean the model performed reasonably well. The developed model was then applied to simulate the water quality changes at the downstream cross-section assuming that the designed restoration programs were implemented. According to the simulated results, the restoration programs could cut down the loads of CODcr and PO4-P about 15%, however, they would have very little effect on the NH3-N removal. Besides, the water quality at the outlet cross-section would be still in class V (3838-02), indicating more measures should be taken to further reduce the loads. The study demonstrated the capability of water quality models to support aquatic ecosystem restorations. 相似文献
130.
High-resolution modeling approach is increasingly being considered as a necessary step for improving the monitoring and predictions of regional air quality.This is especially true for highly urbanized region with complex terrain and land-use.This study uses Community Multiscale Air Quality (CMAQ) model coupled with MM5 mesoscale model for a comprehensive analysis to assess the suitability of such high-resolution modeling system in predicting ozone air quality in the complex terrains of Osaka,Japan.The 1-km and 3-km grid domains were nested inside a 9-km domain and the domain with 1-km grid covered the Osaka region.High-resolution Grid Point Value-Mesoscale Model μgPV-MSM) data were used after suitable validation.The simulated ozone concentrations were validated and evaluated using statistical metrics using performance criteria set for ozone.Daily maxima of ozone were found better simulated by the 1-km grid domain than the coarser 9-km and 3-km domains,with the maximum improvement in the mean absolute gross error about 3 ppbv.In addition,1-km grid results fared better than other grids at most of the observation stations that showed noticeable differences in gross error as well as correlation.These results amply justify the use of the integrated high-resolution MM5-CMAQ modeling system in the highly urbanized region,such as the Osaka region,which has complex terrain and land-use. 相似文献