Reaction Kinetics of Ozone Gas in Green Gram (Vigna radiate)

This study was carried out to evaluate the reaction kinetics of ozone gas in different height (5 and 10 cm), moisture content (10.6 and 13.4% (d.b.)) and gas flow rate (2 and 4 L/min). The decomposition kinetics obtained was first-order model. As far as the half-life of ozone is considered, the highest value obtained was equivalent to 8.72 min for grains ozonated at 5 cm height, 10.6% (d.b.) moisture content and 2 L/min gas flow rate. In the process of ozone reaction rate in green gram grains, height (p < 0.01) and moisture content (p < 0.01) were found to be the key factor for the effectiveness of ozone fumigation.     

EFFICIENT METHOD OF MOMENTS ESTIMATORS FOR INTEGER TIME SERIES MODELS

The parameters of integer autoregressive models with Poisson, or negative binomial innovations can be estimated by maximum likelihood where the prediction error decomposition, together with convolution methods, is used to write down the likelihood function. When a moving average component is introduced this is not the case. To address this problem an efficient method of moment estimator is proposed where the estimated standard errors for the parameters are obtained using subsampling methods. The small sample properties of the estimator are investigated using Monte Carlo methods, while the approach is demonstrated using two well‐known examples from the time series literature.     

A GENERALIZED BLOCK BOOTSTRAP FOR SEASONAL TIME SERIES

When time‐series data contain a periodic/seasonal component, the usual block bootstrap procedures are not directly applicable. We propose a modification of the block bootstrap – the generalized seasonal block bootstrap (GSBB) – and show its asymptotic consistency without undue restrictions on the relative size of the period and block size. Notably, it is exactly such restrictions that limit the applicability of other proposals of block bootstrap methods for time series with periodicities. The finite‐sample performance of the GSBB is also illustrated by means of a small simulation experiment.     

化工设备焊缝安全管理信息系统开发

通过对化工设备焊缝安全管理信息系统进行需求分析和可行性分析,完成了系统的总体设计,利用Microsoft SQL Server 2000作为后台数据库,结合Windows下可视化编程工具Visual Basic 6.0进行了系统开发。系统主要包括登录、信息管理、安全评价、系统设置、数据安全和帮助信息模块,对系统进行测试后,可以满足化工设备焊缝安全管理工作的需要。     

实时数据库系统在聚丙烯装置生产管理中的开发与应用

中国石油化工股份有限公司荆门分公司建立了一套实时数据库系统,通过网络将生产装置DCS系统内的运行数据实时采集,长期存储,为装置的生产管理提供了一个信息平台。在此基础上,笔者根据聚丙烯装置生产管理的实际需要开发了一系列新功能。这些功能的应用提高了工作效率,优化了装置的生产操作,提升了工艺管理水平,收到良好的效果。     

基于市场导向的新疆地区炼焦煤资源的开发与实践

拜城县众泰煤焦化有限公司针对新疆地区冶金焦炭市场需求,对新疆地区炼焦煤资源综合利用的问题进行立项研究,丰富和完善公司产品配方库,抢占市场机遇,取得了显著的经济效益。     

2000m~3液化气球罐的TOFD检测

由于现场施工队伍多、施工工期短等原因,采用100%TOFD+100%UT组合方式取代100%射线检测方式对现场组焊的球罐焊缝进行检测,并编制了检测技术方案。按照该方案对一台球罐进行了TOFD检测,发现了许多圆形、条形缺陷。经超声检测验证,其检测结果与TOFD检测出的缺陷位置基本吻合。     

Solids transport models comparison and fine‐tuning for horizontal,low concentration flow in single‐phase carrier fluid

We determined and fine‐tuned the solids transport models appropriate for predicting the single‐phase carrier fluid velocity to transport solid particles in conduits for horizontal, low concentration flow. A database with 538 experimental data points was compiled. A literature review was performed to determine the data ranges, forces, and mechanisms used to develop 44 models, and their velocity predictions were compared against the database using statistics. Using the dimensionless forms of the models and the data, the model parameters were adjusted to improve their accuracy and identify the dominant forces. At low concentrations: for liquid/solid flow from a bed of solids and gas/solid flow from the bottom of pipelines, the particle weight, and inertial and viscous forces dominate; for gas/solid flow from a bed of solids, the particle weight, and inertial, viscous, and adhesive forces play a role; and gaps exist in the data for large‐diameter pipes and high‐density gases. © 2013 American Institute of Chemical Engineers AIChE J, 60: 76–122, 2014     

主要工艺参数对串联式磨盘挤出机混合性能的影响

采用Polyflow软件模拟了聚合物熔体在串联式磨盘挤出机混炼段内的混合过程。将混合指数和分离尺度作为评价指标,借助统计学方法,分析了主要工艺参数(转速和喂料速率)对串联式磨盘挤出机混合性能的影响。研究结果表明:转速增大,串联式磨盘挤出机的分散混合性能和分布混合性能提高;喂料速率增大,串联式磨盘挤出机分散混合性能下降,但喂料速率对串联式磨盘挤出机分布混合性能影响较小。     

子空间夹角结合时间序列分析判定反应终点

拉曼光谱经过基线校正处理后,运用子空间模式识别原理,反应物水杨酸、醋酸酐以及催化剂氨基磺酸的拉曼光谱作为子空间,各个反应时刻的拉曼光谱作为被关注向量,求取被关注与子空间夹角,通过时间序列分析模型对空间向量夹角变动分析体系内组分变化情况设经验阀值δ(ti)小于0.5判定为反应终点,此时水杨酸的转化率为97.8%。