基于模态叠加法的振动响应修正方法研究概述

针对模态叠加法受模态选取和截断等影响,往往导致动力学计算精度不高,尤其是对高频响应难以预测这一缺点,对多个基于模态叠加的修正方法研究的现状和发展趋势进行了概述,简要分析了各个修正方法的优劣,并结合目前的大规模并行计算技术探讨了添加这些修正方法的可能性。研究表明,模态加速度法是目前相对容易实现的一种修正算法,最易于在大规模并行计算和实际工程应用中实现。     

SRIS对垃圾渗滤液中氨氮去除效能及微生态分析

针对垃圾渗滤液中ρ（NH₃-N）较高、可生化性较差、处理困难的问题,以老龄垃圾渗滤液为研究对象,探讨了改良SRIS（土地快速渗滤系统）对NH₃-N的处理效果与最高处理负荷量,同时分析了系统不同深度的ρ（NH₃-N）的变化,并利用高通量测序技术分析了进水前、后系统中的微生物群落演替情况.结果表明:①在进水ρ（NH₃-N）为125 mg/L左右、水力负荷为0.11 m3/（m2·d）、进水频率为1次/d下,垃圾渗滤液经改良SRIS的一级、二级渗滤柱处理后出水ρ（NH₃-N）平均值为3 mg/L,NH₃-N去除率在97.5%以上;提高水力负荷为0.22 m3/（m2·d）后,NH₃-N去除率为87.27%;进水频率改为2次/d,NH₃-N去除率达到96.17%.②改良SRIS的一级、二级渗滤柱所能处理的最高NH₃-N去除量分别为200和110 mg/L,并且主要在下层和底层部分发生去除.③改良SRIS中下层微生物群落多样性最为丰富,微生物群落以变形菌门（Proteobacteria）为主,在属水平下微小杆菌属（Exiguobacterium）相对丰度最高,同时还存在多种有利于NH₃-N去除的硝化、反硝化细菌以及浮霉菌,为NH₃-N的去除提供了保障.研究显示,改良SRIS对垃圾渗滤液中NH₃-N具有良好的去除效果,可为老龄垃圾渗滤液的有效处理提供借鉴.      

Processing and Characterization of Short-Fiber Reinforced Jute/Poly Butylene Succinate Biodegradable Composites: The Effect of Weld-Line

Fabrication of complex injection molded parts often involves the use of multiple gates. In such situations, polymer melts from different gates meld to form the molded part (weld line). This paper reports on the fabrication and characterization of the mechanical and morphological properties of short fiber reinforced jute/poly butylene succinate (PBS) biodegradable composites. The effect of a dual gated mold in the fabrication of welded specimens was a key focus of the investigation. It was observed that incorporation of jute fiber (10 wt%) conferred drastic changes on the stress–strain properties of the matrix as the elongation at break (EB), dropped from 160% in the matrix to just 10% in the composite. The tensile strength of the composite was lower than that of the matrix. However, it is noteworthy that the tensile modulus of the composite increased. Bending test also revealed that both bending strength and modulus increased with the incorporation of jute. Morphological studies of the tensile fracture surface using SEM revealed two types of failure mode. Ductile failure was indicated by plastic deformation at the initiation of fracture followed by brittle failure. The good interfacial bonding indicated between jute and PBS was attributed to positive interaction between the two polar polymers. A comparison of the non-weld and weld-line samples revealed that the weld-line composites have better mechanical integrity than the corresponding polymer matrix with weld line. The results also revealed that elongation at break and toughness are most sensitive to the presence of the weld-line whereas flexural properties are least sensitive.     

蒙城地震台地磁绝对观测数据处理分析软件

蒙城地震台地磁绝对观测数据主要通过手工方式计算处理,由于内容多而繁琐,很容易出现人为错误,而且工作效率不高。本文介绍了“蒙城地震台地磁绝对观测数据处理分析软件”,该软件将绝对观测日常数据处理工作有效整合,形成了流程,提高了数据处理效率。并能够对数据进行误差统计、趋势分析等,以了解观测资料的实际状况。     

天然沸石的加工技术及其在水处理中的应用

论述了天然沸石的吸附、离子交换和催化性能,介绍了沸石的超细粉碎、选矿提纯、化学增白、改性或改型、人工合成和再生等加工技术．从去除有机污染物、去除氨氮、降低氟含量、去除重金属离子、作污水滤料、消除放射性物质等方面回顾了沸石在水处理中的应用．并对应用前景和未来发展进行了展望。     

电除尘器分布板孔形对气流分布影响的仿真研究

针对不同气流分布板孔形,采用欧拉-拉格朗日多相流模型,应用CFX软件对电除尘器内部流场进行数值模拟计算,获得气流分布板孔形对气流均匀性影响的关系规律。仿真结果表明,孔形为方形的气流分布板能获得较佳的气流分布均匀性。     

城市安全生产风险评估调研和信息处理方法研究

为城市安全生产风险评估调研工作的合理有序开展,本文结合实际案例归纳了城市安全生产风险评估调研的目的、范围、内容和流程,具体介绍了走访座谈法、常专结合法、函件调研法等信息采集方法,总结了综合归纳法和逻辑处理法等信息处理方法。结果表明,在调研的不同阶段运用不同的调研方法可有效获取城市安全生产风险源信息及安全生产基本信息,为城市安全生产风险评估工作奠定坚实的信息数据资料支撑。     

浅谈代数问题中的数形结合

对数与形的结合在代数解题中的广泛应用作了一些归纳和扩充,主要概括了它在求函数值域与极值(最值)、解不等式(不等式组)、解方程(方程组)三个方面的应用.通过一些典型例题,提出了相应的方法与常用的技巧,因此,数与形不再是分离的主体,而是紧密地结合在一起,并渐渐形成了许多新型数学分支.     

An architectural model of spring wheat: Evaluation of the effects of population density and shading on model parameterization and performance

ADELwheat is an architectural model that describes development of wheat in 3D. This paper analyzes the robustness of the parameterization of ADELwheat for spring wheat cultivars in relation to plant population density and shading. The model was evaluated using data from two spring wheat experiments with three plant population densities and two light regimes. Model validation was done at two levels of aggregation: (a) by comparing parameterization functions used as well as parameter values to the data (leaf and tiller appearance, leaf number, blade dimensions, sheath length, internode length) and (b) by comparing ground cover (GC) and leaf area index (LAI) of simulated virtual wheat plots with GC and LAI calculated from data. A sensitivity analysis was performed by modulating parameters defining leaf blade dimensions and leaf or tiller appearance rate.In contrast to population density, shading generally increased phyllochron and delayed tiller appearance. Both at the level of the organ and at the level of the canopy the model performed satisfactorily. Parameterization functions in the model that had been established previously applied to independent data for different conditions; GC and LAI were simulated adequately at three population densities. Sensitivity analysis revealed that calibration of phyllochron and blade area needs to be accurate to prevent disproportional deviations in output.The robustness of the model parameterization and the simulation performance confirmed that the model is a complete architectural model for aboveground development of spring wheat. It can be used in studies that require simulation of spring wheat structure, such as studies on plant–insect interaction, remote sensing, and light interception.     

气浮+CASS组合工艺在肉鸡屠宰废水处理中的应用

屠宰废水是一种常见的食品加工废水,废水中有机污染物浓度较高,且含有脂肪、蛋白质等大分子有机物和毛发、动物内脏等杂物.絮凝气浮 CASS组合工艺在铁岭某肉鸡屠宰公司废水处理工程应用中,取得了较为显著的效果,CODcr去除率98%,BOD5去除率98%,SS去除率98%,氨氮去除率58%,动植物油去除率91%;出水水质均满足GB13457-92<肉类加工工业水污染物排放标准>要求.该工艺具有投资少、操作简单、处理效果好、便于管理的特点,易于在同类食品加工废水处理中推广应用.