老虎台矿55002#掘进面通过F7-1断层前后微震事件的时空特征分析

冲击地压作为一种特殊的矿压显现形式,对抚顺矿业集团老虎台矿深部开采的安全生产造成了严重的影响,在该矿的实际生产中,地质条件是引发冲击地压发生的重要因素。鉴于微震监测系统是目前在煤矿井下监测冲击地压应用较为广泛的手段之一,本文利用波兰ARAM IS/MA微震监测系统对老虎台矿55002掘进工作面通过F7-1断层前后的微震特征信号进行连续观测,分别从时间和空间上研究此掘进面通过断层前后的微震特征,验证了一种典型的冲击地压发生时间前后的微震活动规律,并结合实际地质条件从位置上分析了微震事件与断层等地质构造之间的关系,进而根据空间分析结果圈定了重点防治冲击地压区域,使老虎台矿在该工作面掘进生产中提前采取相应的防范措施,顺利通过断层等地质构造异常区域,确保了安全生产。     

Chemical looping combustion for power generation—Concept study for a 10 MWth demonstration plant

A semi-commercial 10 MW_th chemical looping combustion (CLC) plant for power production is proposed as a next scale demonstration plant after successful operation of a 120 kW CLC pilot rig. The design criteria for the CLC boiler are derived from the experience obtained from the CLC pilot rig at Vienna University of Technology. The IPSEpro simulation environment is chosen for implementation of the process flow sheet of the CLC power plant. A single pressure steam cycle is suggested for this small scale demonstration plant. Heat exchangers and a five-stage steam turbine are arranged. Basic design parameters of the power plant are derived from detailed mass and energy investigations and discussed. It turns out that the net electric efficiency of such a small scale plant can be expected to be in the range of 32.5–35.8%. However, a demonstration of CLC at such a scale is necessary in order to gain confidence in more sophisticated CLC power generation concepts at larger scale.     

氢化物发生原子荧光光度法测定水中锑的不确定度评定

介绍了原子荧光光度法测定水中锑的不确定度评定方法,分析和识别在测定过程中的不确定度来源,较为全面地评定了测量不确定度,最后计算出测定结果的合成标准不确定度和扩展不确定度.结果表明,标准溶液配制过程和标准曲线拟合引起的不确定度是原子荧光光度法测定水中锑含量不确定度的主要来源.     

矩形和钟形震源时间函数对地震动模拟结果的影响比较

首先介绍了用于地震动数值模拟的国际通用软件COMPSYN程序,并对此进行了二次开发,将其震源时间函数由矩形函数改为钟形函数,通过与全空间的解析解计算结果的对比,验证了修改后程序的正确性.通过对比2种震源时间函数的频谱特点,指出矩形函数的高频成分丰富,不利于地震动的模拟.2种震源时间函数下用COMPSYN程序对同一观测点...     

一种纳米气溶胶发生系统的设计及性能测试

气溶胶发生系统是校准大气颗粒物测量仪器、研究纳米颗粒物特性和开展烟雾箱模拟实验的必备仪器之一.针对现有气溶胶发生仪器稳定性差和不利于外场监测等缺点,本研究设计了一款新型纳米气溶胶发生系统(包括气溶胶发生器和扩散干燥管),并通过搭建实验系统对该仪器的工作性能进行了测试.在性能测试中使用氯化钠(NaCl)-水溶液和癸二酸二辛酯(DOS)-异丙醇溶液分别产生固态NaCl和液态DOS气溶胶,利用扫描电迁移率粒径谱仪测试生成气溶胶的粒径分布.测试结果表明,通过调节溶液浓度(0.01～0.50 g·L-1)和载气流量(1.64～3.67 L·min-1),生成不同大小(几何平均粒径:25～51nm)和不同数浓度(106～107个·cm-3)的气溶胶.对仪器稳定性能测试发现,在3 h的测试时间里生成的气溶胶几何平均粒径变化小于6%,数浓度变化小于12%.     

2000~2010年大鹏湾颗粒有机物的年变化和年际变化

依据2000～2010年每月一次的调查资料,简要描述和讨论了大鹏湾中颗粒有机物(particulate organic matter,POM)质量浓度的时空分布,并结合叶绿素a(chlorophyll a,Chl-a)实测数据探讨POM的组成和滞留时间.结果表明,大鹏湾的水动力条件对POM的分布变化影响不大,POM质量浓度为(1.1±0.8)mg·L-1,与珠江口伶仃洋和大亚湾的差别不大,但比南海北部的高.在表层,POM与Chl-a之间存在显著正相关,浮游植物有机物(phytoplankton POM,PPOM)∶Chl-a比率为70 g·g-1左右,由此估算的大鹏湾PPOM质量浓度为(0.31±0.39)mg·L-1,约占POM的28%.由初级生产力(primary productivity,PP)和累计POM(integrated POM,IPOM)估算的大鹏湾中POM的滞留时间约为6.5 d,与东海南部沿岸陆架区POC的相近.11 a调查期间,PP的年际变化略呈下降趋势,而POM和IPOM的年际变化呈较明显的上升趋势,暗示难降解的碎屑POM在大鹏湾中逐渐积累.     

Effects of idle time on biological phosphorus removal by sequencing batch reactors

Three identical sequencing batch reactors （SBRs） were operated to investigate the effects of various idle times on the biological phosphorus （P） removal. The idle times were set to 3 hr （R1）, 10 hr （R2） and 17 hr （R3）. The results showed that the idle time of a SBR had potential impact on biological phosphorus removal, especially when the influent phosphorus concentration increased. The phosphorus removal efficiencies of the R2 and R3 systems declined dramatically compared with the stable R1 system, and the Prelease and P-uptake rates of the R3 system in particular decreased dramatically. The PCR-DGGE analysis showed that uncultured Pseudomonas sp. （GQ183242.1） and β-Proteobacteria （AY823971） were the dominant phosphorus removal bacteria for the R1 and R2 systems, while uncultured γ-Proteobacteria were the dominant phosphorus removal bacteria for the R3 system. Glycogen-accumulating organisms （GAOs）, such as uncultured Sphingomonas sp. （AM889077）, were found in the R2 and R3 systems. Overall, the R1 system was the most stable and exhibited the best phosphorus removal efficiency. It was found that although the idle time can be prolonged to allow the formation of intracellular polymers when the phosphorus concentration of the influent is low, systems with a long idle time can become unstable when the influent phosphorus concentration is increased.     

Predicting functional response and size selectivity of juvenile Notonecta maculata foraging on Daphnia magna

A mechanistic model was developed to assess the impact of predation of juvenile Notonecta maculata on size structured Daphnia magna populations and to provide a framework for quantifying the backswimmers uptake of food. Results of experiments and model predictions clearly demonstrate selective predation of backswimmers when fed with a choice of daphnid size classes, with patterns of selectivity differing across N. maculata instars. The model describes the foraging process empirically on the base of a general predation cycle including four conditional events instead of using classic functional response curves. For model parameterisation components of predation, namely probability of encounter, attack and success as well as time spent on handling prey was directly observed by means of video tracking experiments. Since attack rate, capture success and handling time appeared to be a function of prey size differing between Notonecta instars, the model takes into account ontogenic changes in both predator and prey characteristics. Independent data of functional response and size selectivity experiments were used for model validation and proved the model outcome to be consistent with observations.     

水生高等植物对悬浮泥沙的去除研究

根据自然水体湿生植物（挺水植物）、浮叶植物以及沉水植物的空间分布规律，利用风车草（Cyperus alternifolius）、石菖蒲（Acorus tatarinowii）、菱（Trapa japonica）、金鱼藻（Ceratophyllum demersum）、轮叶黑藻（Hydrilla verticillata）和苦草（Vallisneria spiralis）等水生植物构建由挺水植物、浮叶植物到沉水植物的串联系统，含沙水依次流经挺水植物、浮叶植物和沉水植物，测定各级植物对泥沙的去除效果。结果显示，输入悬浮泥沙浓度依次为21.76、37.04、45.09、71.18 mg/L，水力停留时间（HRT）分别为12、16、24、24 h，水生高等植物串联系统对悬浮泥沙的去除率分别为68.1%、71.7%、77.5%、74.0%，表明水生高等植物可有效去除水体中的悬浮泥沙，改善了透明度。水力滞留时间对植物去除悬浮泥沙的效果有较大的影响，水力滞留时间长，即使输入悬浮泥沙浓度很高，去除率和单位时间的净去除量也较高;浅水区的挺水植物对进水高浓度悬浮泥沙的有效过滤作用减缓了悬浮泥沙对深水区沉水植物的胁迫压力;沉水植物能进一步去除悬浮泥沙，抑制再悬浮作用，对水生生态系统的稳定有十分重要的作用。     

跨西安地裂缝建设一般建筑物的可能性探讨

通过对跨西安地裂缝上的建筑物没有遭到地裂缝破坏的典型事例分析认为，采用时间避让法及地基和结构处理措施，一般建筑可以跨地裂缝建设。