一种新型复合固化剂固土试验研究

通过化学分析、扫描电镜、无侧限抗压强度等试验,研究了一种新型复合固化剂(SSK)加固黄土的微观结构及其强度特征。试验结果表明:黄土中加入一定量的SSK固化剂能够显著地提高土体的强度,使得加固后的黄土能够满足路基等工程实际的需要。     

黄土地区公路路堑高边坡植物防护探讨

分析了黄土地区公路路堑高边坡植物防护主要形式,指出了黄土路堑边坡植物防护存在的主要问题,如防护措施偏少,成活率低;植物防护"贵族化"严重;植被退化等。最后提出植物防护的一些对策,可为高速公路建设中黄土路堑高边坡植物防护提供参考。     

车用催化转化器的声衰减特性研究

利用微孔媒介的声传播特性来研究催化转化器的声学特性。研究表明,当利用圆形微孔替代方形微孔时,在低剪切波数下存在较大误差;高温使微孔的传播常数向低频段扩展、移动,但是整个曲线的趋势未变。相同特征尺寸时,用圆形微孔计算催化转化器的衰减量要大于用方形微孔的情况;温度升高,催化转化器的衰减量也升高。试验证明,声衰减量随频率的增加而增大,并且测量的声衰减量略大于理论计算值。     

直流无刷电机再生制动系统试验台的设计与验证

基于再生制动理论,以电动汽车用轮毂电机为主体,搭建了直流无刷电机再生制动试验台。以回收能量最大化为目标,提出了相应的再生制动控制策略。结合电机的输出特性和工作原理,利用SIMULINK软件建立了再生制动系统模型。通过模型仿真和试验台试验结果的对比分析,验证了再生制动试验台设计方案的可行性和控制策略的合理性。     

搅拌桩加固河漫滩相软土地基沉降特性分析

结合宁淮高速公路南京段河漫滩相软土地基2年多的沉降观测资料,分析了搅拌桩加固软土地基沉降变形规律。分析表明:搅拌桩加固的河漫滩相软土地基填筑期沉降与填土高度近似成线性关系;预压期沉降速率收敛很快;地基沉降符合双曲线型规律,最终沉降可以采用双曲线法预测。     

丘陵地区小城镇“四好农村路”规划建设思考———以浙江绍兴新昌为例

农村公路是农业和农村发展的先导性、 基础性设施， 对于保障群众生产生活的基本条件， 促进社会主义新农村建设和乡村振兴战略具有重要现实意义。 基于丘陵地区普遍存在的路网布局不协调， 以及农村公路技术条件、 路域环境较差等问题， 文章以浙江绍兴新昌为例， 统筹考虑小城镇空间结构、 社会经济需求和特色节点等要素， 提出 “成网、 布点、 亮线” 三点策略， 构建规模适当、 结构合理、 协调融合、 美丽富民的 “四好农村路” ， 为丘陵地区小城镇农村公路规划建设提供新思路。     

潜艇舱室空气处理技术研究进展

潜艇舱室内空气质量是影响潜艇续航的重要因素之一。舱室内污染物质来源多样,大气成分复杂,处理难度大,给相关技术发展带来挑战。针对其特殊性,综述了潜艇舱室内空气处理技术的研究进展,系统介绍了当前国内外不同形式的潜艇舱室空气处理工艺,重点阐述了不同工艺的原理、现状及优缺点,为探索潜艇舱室空气处理新途径、新技术提供参考和思路。     

桥桩二次托换技术在地铁工程中的应用

在地铁设计与施工中,经常遇到地铁区间、车站需穿越城市既有桥桩和房屋基础的情况,在改线和撤迁无果时就需要对既有桥桩或房屋基础进行加固或托换处理。此时,如何保障既有桥桩或房屋的安全与正常使用是整个托换的根本。文章结合工程实际,提出了主动与被动相结合的二次托换技术。     

喷浆护壁钻孔灌注桩施工工艺

介绍了一种在特殊地质条件下灌注桩施工的新工艺———喷浆护壁钻孔灌注桩施工工艺,介绍了该工艺的施工步骤、施工方法及其特点,并通过实例与一般灌注桩施工方法进行了比较。     

Sediment community biomass and respiration in the Northeast water polynya, Greenland: a numerical simulation of benthic lander and spade core data

Sediment community metabolism (oxygen demand) was measured in the Northeast Water (NEW) polynya off Greenland employing two methods: in situ benthic chambers deployed with a benthic (GOMEX) lander and shipboard laboratory Batch Micro-Incubation Chambers (BMICs) utilizing ‘cores’ recovered from USNEL box cores. The mean benthic respiration rate measured with the lander was 0.057 mM O₂ m⁻² h⁻¹ (n = 5); whereas the mean measured with the BMICs was 0.11 mM O₂ m⁻² h⁻¹ (n = 21; p < 0.01 that the means were the same). In terms of carbon fluxes (14 and 27 mg C m⁻² d⁻¹), these respiration rates represent ca. 5–15% of the average net primary production measured in the euphotic zone in 1992. The biomass of the bacteria, meiofauna and macrofauna were measured at each location to quantify the relationship between total community respiration and total community biomass (mean 1.42 g C m⁻²). Average carbon residence time in the biota, calculated by dividing the biomass by the respiration, was on the order of 50–100 days, which is comparable to relatively oligotrophic continental margins at temperate latitudes.The biomass and respiration data for the aerobic heterotrophic bacteria, the infaunal invertebrates (meiofauna and macrofauna), and the epifaunal megabenthos (two species of brittle stars) are summarized in a ‘steady-state’ solution of a sediment food chain model, in terms of carbon. This carbon budget illustrates the relative importance of the sediment-dwelling invertebrates in the benthic subsystem, compared to the bacteria and the epibenthos, during the summer open-water period in mud-lined troughs at depths of about 300 m. The input needed to drive heterotrophic respiratory processes was within the range of the input of organic matter recorded in moored, time-sequencing sediment traps.A time-dependent numerical simulation of the model was run to investigate the potential responses of the three size groups of benthos to abrupt seasonal pulses of particulate organic matter. The model suggests that there is a time lag in the increase in bottom community biomass and respiration following the POC pulse, and provides hypothetical estimates for the potential carbon storage in the summer (open water), followed by catabolic losses during each ensuing winter (ice covered).This sequence of storage and respiration may contribute to the process of seasonal CO₂ ‘rectification’ (sensu Yager et al., 1995) in some Arctic ecosystems.