印染废水活性污泥代谢状态光偏转快速检测法

针对现有活性污泥检测方法过程繁琐、耗时长、检测结果滞后的局限,提出了光偏转快速检测法.在污泥负荷为0.33KgCOD/（kg MLSS·d）、水力停留时间为15h的印染废水完全混合式活性污泥系统中,投放粒径4mm、具有20μm微孔结构的聚乙烯醇（PVA）凝胶小球以负载微生物,并在小球达到稳定状态后,对其表面处因外界溶液与微生物代谢产物交换产生的浓度梯度变化,借助光斑分析仪进行光偏转检测,同时测定与光偏转检测结果相对应的15h后的出水COD及COD去除率.连续10个月的检测发现,小球中富集的主要为细菌,当进水COD由91.95mg/L增至519.4mg/L时,小球的光偏转值从229.51μm增加至299.97μm,COD去除率从16.03%提高至66.99%;当DO浓度为1.5mg/L~5mg/L时,小球光偏转值在DO=4mg/L时增至最大为309.3mg/L,对应状态下COD去除率增至最大为61.18%;在pH值为6~9时,小球光偏转值在pH=7时增至最大为293.96μm,对应状态下COD去除率也达到最大值为64.83%;当重金属Cr³⁺浓度增至50mg/L时,微生物活性逐渐受到抑制,小球光偏转值在Cr³⁺浓度为20mg/L时降至269.7μm,随后随着Cr³⁺浓度的增加,微生物细胞受损,胞内物质溶出,小球光偏转值有所增大,对应状态下COD去除率从52.5%持续降低至25.73%.结果表明：该方法可快速获得活性污泥代谢状态变化信息,且依据特定条件下小球光偏转值变化能够预测随后印染废水COD的去除效果.利用三维荧光光谱初步探究了微生物代谢引发光偏转的机理,发现参与微生物代谢的主要有机物为酪氨酸、芳香类蛋白及色氨酸.     

Multiscale Analysis of Hydrology in a Mountaintop Mine‐Impacted Watershed

In the Appalachian region of the eastern United States, mountaintop removal mining (MTM) is a dominant driver of land‐cover change, impacting 6.8% of the largely forested 4.86 million ha coal fields region. Recent catastrophic flooding and documented biological impairment downstream of MTM has drawn sharp criticism to this practice. Despite its extent, scale, and use since the 1970s, the impact of MTM on hydrology is poorly understood. Therefore, the goal of this study was a multiscale evaluation to establish the nature of hydrologic impacts associated with MTM. To quantify the extent of MTM, land‐cover change over the lifetime of this practice is estimated for a mesoscale watershed in southern West Virginia. To assess hydrologic impacts, we conducted long‐term trend analyses to evaluate for systematic changes in hydrology at the mesoscale, and conducted hydrometric and response time modeling to characterize storm‐scale responses of a MTM‐impacted headwater catchment. Results show a general trend in the conversion of forests to mines, and significant decreases in maximum streamflow and variability, and increases in base‐flow ratio attributed to valley fills and deep mine drainage. Decreases in variability are shown across spatial and temporal scales having important implications for water quantity and quality. However, considerable research is necessary to understand how MTM impacts hydrology. In an effort to inform future research, we identify existing knowledge gaps and limitations of our study.     

加入WTO对我国检测业的影响及对策

本文就加入WTO后我国检测业所面临的形势进行了分析，并就我国检测工作现状、存在的问题和如何应对入世后的挑战提出了对策。     

低气压下火焰视频图像特征研究

为了进行非密封飞机机舱内视频火灾探测技术的研究,借助中国科学技术大学QR0-12步入式环境低气压试验舱开展低气压下(100kPa,90kPa,70kPa,50kPa和30kPa)火焰视频图像特征研究。在实验舱中用正庚烷作为可燃物进行点火实验,拍摄火焰视频,研究低气压环境下火焰的颜色、空间变化、运动、相对稳定性、边缘粗糙度、相邻帧火焰区域面积变化率、面积重叠率、相关性特征。实验结果表明,火焰的颜色、空间变化特征不会随气压变化而变化;而火焰动态特征等都会因气压的不同而发生变化。因此,火焰的颜色和空间变化特征在低气压环境中仍可用于火焰区域分割和识别,而其他动态特征会随着气压发生变化,不能用常压下的方法来训练分类模型,但仍可以用以区别火焰和静止的疑似区域。     

飞机货舱低气压环境对火灾探测参量影响研究

旨在为飞机货舱火灾探测系统设计和研制提供理论支撑,在飞机货舱环境模拟实验舱内开展了70kPa、80kPa、90kPa和100kPa下正庚烷火灾实验,分析了低气压环境对顶棚温度、烟气密度和气体浓度火灾探测参量的影响规律。低压下空气密度较小,卷吸系数减小,导致顶棚最高温升增加,顶棚温度衰减变快。同时,低压下烟气密度降低,并与压力呈指数关系,指数系数约为0.946,扩展了前人研究结果的应用范围。CO浓度最大值随压力降低而增加,且CO增长速率与压力呈负指数关系。CO2增长速率随着压力降低而略有减小。     

飞机货舱烟雾探测系统优化布置技术及平台研发

对飞机货舱烟雾探测系统布置原则进行了论述,提出了一套飞机货舱烟雾探测系统布置方法,并开发出一套烟雾探测系统布置优化平台。对烟雾探测系统布置中的几个关键技术问题进行了详细讨论,并以某型运输机货舱为实例进行了仿真计算。     

利用瓦斯抽采穿层钻孔预测煤层小断层工程实践

小构造附近是瓦斯灾害容易发生的危险地带,探明煤层小构造对煤矿的安全生产至关重要。基于古汉山矿二1煤层瓦斯抽采工程特点,分析利用瓦斯抽采穿层钻孔进行地质构造探测的可行性,根据试验工作面、底抽巷、瓦斯抽采穿层钻孔空间关系,建立煤层小构造预测数学模型及预测方法。结合试验工作面瓦斯抽采穿层钻孔现场施工数据特点,分析钻孔误差及校正方法,绘制煤层底板三维曲面图、煤层底板等高线图、煤层底板趋势面残差图及煤层厚度等值线图。根据煤层底板预测图件,对小构造分布做出了综合判断:在工作面走向通尺360～390 m、倾向上距离运输巷35 m处,可能存在落差1. 5 m、走向N45°W、延伸长度20 m左右的小断层。现场实际揭露地质情况与理论预测结果基本吻合,工作面推进与小构造距离小于20 m时,瓦斯突出危险程度明显增大。     

Measurement method for objective cyclist behavior parameters

Abstract

Objective: The objective of this research is to study the feasibility of measuring behavioral indicators that reflect effects of infrastructure and interaction with other road users.

Methods: An observation study was performed using 6 cameras above a separated cycle path next to a road which included a crossing with both cyclists and cars. A learning method based on Single Shot MultiBox Detector was applied to automatically detect the cyclists, and cyclist tracks were determined. Next, kinematic parameters were calculated from the cyclists’ tracks. Amongst others, the cyclists’ intensity, speed, position on the cycle path, and the distance to each other were analyzed for a busy period as well as for a quiet period of the day.

Results: With the measurement method developed in this study it is possible to analyze the cyclists’ intensity, the space they use at the cycle path, their average velocity, waiting times, the space and velocity amongst each other, and red light negation. However, collisions were not seen in the dataset analyzed, and the data is not sufficiently accurate to analyze sudden braking actions.

Conclusion: It can be concluded that the developed measurement method provides insight of the cyclists’ behavior in such a way that it can already be used for obtaining information to make changes to the infrastructure that will improve the comfort and safety of cyclists. The method could be further developed for doing qualitative comfort and safety analyses, and for doing analyses of the interaction between various types of road participants.     

市售贝类麻痹性贝毒快速生化检测方法探究

为了研究快速检测海产品中低浓度麻痹性贝毒(paralytic shellfish poisoning,PSP)的生化方法,在传统小白鼠法的基础上,使用浓度(以STXeq计)为1和0.2μg/kg的市售双壳贝类PSP提取液对小鼠进行腹腔注射,分别研究暴露15、60、120min后小鼠血液中ACh、AChE、NO和NOS的变化情况.结果发现,低浓度(0.2μg/kg)、短时间(15min)条件下仅ACh含量发生显著变化[与对照组相比p0.05,含量(以蛋白计)为(141.2±14.8)μg/mg];而NO与NOS却在长时间(120min)暴露后才发生改变[与对照组相比p0.05,分别为(68.7±3.8)μmol/g及(40.1±4.9)U/mg].在高浓度下,3个时间点的ACh含量也均发生显著变化.结果表明,在低浓度及短时间条件下反映PSP效应的指标仅是ACh,从而可以尝试选择其作为快速检测PSP的生化指标.