基于分子动力学的胶粉改性沥青中胶粉与沥青相容性研究

为了研究胶粉改性沥青中胶粉与沥青之间的相容性,采用Materials Studio分子模拟软件,构建了沥青四组分代表分子模型与橡胶代表分子模型;同时以四组分分析试验为基础,构建了沥青分子组,在不同温度下对沥青分子组模型和橡胶代表分子模型进行了分子动力学计算,得到了两者的溶解度参数和分子势能.结果表明:沥青体系溶解度参数随着温度的升高逐渐减小;在160℃下沥青溶解度参数与橡胶代表分子——丁苯橡胶(SBR)溶解度参数差值达到最小,沥青与橡胶分子之间的势能达到最大,表明在160℃下沥青与胶粉达到最佳相状态;胶粉改性沥青整体相容稳定.     

Induced fabric anisotropy of granular materials in biaxial tests along imposed strain paths

In granular materials, loading on an initially isotopic assembly usually induces particle rearrangement, and this is referred to as the induced anisotropy of fabric. A series of biaxial tests are conducted along various strain paths using DEM to investigate the evolution of the induced anisotropy. The evolution of both the overall contact network and the sub-networks (the strong and weak) are examined separately. Results of DEM simulations indicate that the evolution of the fabric deviator in the overall contact network can be described as a power function of the stress ratio prior to the peak stress ratio that depends on the imposed dilation rate. A unique fabric-stress relation is obtained for the strong sub-network, which is independent of the strain path, the initial porosity and the confining pressure. Moreover, deformation instability is observed only along dilatant strain paths, which can be related to the degradation or even collapse of a weak sub-network, even though the strong sub-network dominates the strength of the granular assembly.     

Simplified Calculation Methods for Static Behaviors of Triple-Tower Suspension Bridges and Parametric Study

International Journal of Steel Structures - In this paper, simplified formulas to determine the static behaviors of triple-tower suspension bridges were derived, including the formulas for the...     

Role of molecular structure on bioelectrochemical reduction of mononitrophenols from wastewater

The effect of nitro-substituent on mononitrophenol (o-nitrophenol (ONP), m-nitrophenol (MNP) and p-nitrophenol (PNP)) reduction in a bioelectrochemical system (BES) was investigated in this study. The results show that the removal of all three nitrophenols was significantly enhanced with more negative cathode potential and shortened hydraulic retention time in the BESs. Moreover, the reduction of the three nitrophenols followed in the order of ONP > MNP > PNP in the BESs. Both quantum chemical calculation using density function theory and cyclic voltammetry analysis confirmed the reductive sequence of the three nitrophenols. In addition, the acute toxicity of nitrophenol effluent significantly decreased while its biodegradability was enhanced after treatment in the BES. Therefore, the BES technology offers bright prospects for efficient treatment of nitrophenol-containing wastewater.     

A modeling approach to describe ZVI-based anaerobic system

Zero-valent iron (ZVI) is increasingly being added into anaerobic reactors to enhance the biological conversion of various less biodegradable pollutants (LBPs). Our study aimed to establish a new structure model based on the Anaerobic Digestion Model No. 1 (ADM1) to simulate such a ZVI-based anaerobic reactor. Three new processes, i.e., electron release from ZVI corrosion, H₂ formation from ZVI corrosion_, and transformation of LBPs, were integrated into ADM1. The established model was calibrated and tested using the experimental data from one published study, and validated using the data from another work. A good relationship between the predicted and measured results indicates that the proposed model was appropriate to describe the performance of the ZVI-based anaerobic system. Our model could provide more precise strategies for the design, development, and application of anaerobic systems especially for treating various LBPs-containing wastewaters.     

环境友好为切入点的基层中医医疗环境建设研究——以河源市中医院建筑改扩建工程为例

河源市中医院新院建筑改扩建工程设计,是以环境友好概念为切入点而制定相关的设计原则。不仅要坚持以改造建设为主要,有重点、有节制地介入医疗建筑的设计思路,而且在保护传统中医文化的同时,努力改善以病人为中心医疗环境和就诊条件的设计方法,从而实现基层中医医疗环境建设走向良性循环的发展道路。     

低能量沥青温拌技术的应用与实践

低能量沥青温拌技术作为沥青混合料泡沫温拌技术的一种,其生产、施工过程中不需要添加任何温拌剂,因没有温拌剂生产过程的能耗与排放,系统能耗更低,并且在节约成本方面具有明显优势,这使得低能量沥青温拌技术迅猛发展,成为当前世界各国最感兴趣的温拌技术之一。笔者通过其与热拌沥青混合料的对比,介绍了低能量沥青温拌技术在欧洲的应用和实践,提出了低能量沥青温拌技术推广应用需要解决的关键性问题。     

广州西江引水工程盾构法关键技术的应用

结合广州市西江引水工程输水隧道建设经验,总结了输水隧道盾构法建设中需要突破的若干关键技术,可供类似工程设计参考借鉴,以推动深层城市排水、输水隧道的技术进步。     

超高层建筑设计风荷载的选用

在超高层建筑的结构设计过程中,各种参数的使用和指标的控制十分重要,高层建筑对风力作用较敏感,使得风荷载的取值显得较为重要,本文将借助工程实例进行分析,供大家参考。     

武汉经开万达广场CloudMAX云智能管理系统的应用

本文主要介绍了深圳新基点基于自身产品升级开发的CloudMAX云智能管理系统在武汉经开万达广场的应用,包括系统结构、应用特点和主要实现功能。