锅壳锅炉后管板孔桥裂纹事故的分析及处理

分析了锅壳锅炉后管板裂纹产生的原因，阐述了事故发生的机理和处理方法。     

Effect of Cross-Linking Waste Protein with Diepoxides on its Biodegradation under Anaerobic Conditions

Biodegradability testing was performed in an aqueous environment under anaerobic conditions after inoculation with digested sludge from municipal wastewater treatment plant. In cross-linking with 1,2:3,4-diepoxybutane in limits 0.8–9.1% weight, biodegradability degree decreased from 76.8 to 62.2%; when 1,2:7,8 diepoxyoctane in quantities 1.1–13.2% weight was used, biodegradability degree dropped more prominently – from 72.3 to 22.8%. There is obviously a direct connection between growing cross-link degree (assessed by so-called fixation index) and decreasing readiness to biodegradation, apparently owing to build-up of a network forming an obstacle to access of micro-organisms and enzymes.     

青藏铁路50年内不惧冻土

青藏铁路有553公里从冻土区经过,而高原冻土的融沉和冻胀,会造成路面的坑坑洼洼,给行车留下安全隐患。因此曾有“青藏线10年后会因冻土退化出现安全问题”的说法,对此,风火山观测站对外宣称,青藏铁路能够克     

城市烟花爆竹安全监控与业务管理综合信息系统的研究和开发

对城市烟花爆竹安全监控与业务管理综合信息系统的需求进行分析;提出了网络化信息管理系统的设计架构和功能设置;并设计开发了城市烟花爆竹安全监控与业务管理综合信息系统,将先进的网络通讯技术、数据实时采集技术、组态技术、安全监控与预警技术和基于W eb的信息管理软件开发技术进行集成设计;实现了基于烟花爆竹仓库现场实时数据监测结果的多媒体联动、多用途智能报警监视硬件设备和配套的业务管理软件的信息融合。     

污泥淤砂分离器再分离底流污泥

研究了污泥淤砂分离器对分离原污泥所得的底流污泥进行再分离时,分离分流污泥的性质。实验结果表明,原污泥MLVSS/MLSS为0.372,1次分离后得到的底流污泥MLVSS/MLSS为0.222,2次分离后得到的底流污泥MLVSS/MLSS为0.126,表明通过底流污泥再分离,能够进一步降低底流污泥中生物有机质的含量,提高底流污泥中无机淤砂的含量。同时,原污泥CST为2.85(s·L)/g SS,1次分离后得到的底流污泥CST为0.98(s·L)/g SS,2次分离后得到的底流污泥CST为0.12(s·L)/g SS,表明底流污泥再分离进一步提高了底流污泥的脱水性能,最终得到的底流污泥脱水性能良好。     

Forest Die-Back Modified Plankton Recovery from Acidic Stress

We examined long-term data on water chemistry of Lake Rachelsee (Germany) following the changes in acidic depositions in central Europe since 1980s. Despite gradual chemical recovery of Rachelsee, its biological recovery was delayed. In 1999, lake recovery was abruptly reversed by a coincident forest die-back, which resulted in elevated terrestrial export of nitrate and ionic aluminum lasting ~5 years. This re-acidification episode provided unique opportunity to study plankton recovery in the rapidly recovering lake water after the abrupt decline in nitrate leaching from the catchment. There were sudden changes both in lake water chemistry and in plankton biomass structure, such as decreased bacterial filaments, increased phytoplankton biomass, and rotifer abundance. The shift from dominance of heterotrophic to autotrophic organisms suggested their substantial release from severe phosphorus stress. Such a rapid change in plankton structure in a lake recovering from acidity has, to the best of our knowledge, not been previously documented.     

Stand-alone wind power system with battery/supercapacitor hybrid energy storage

This paper presents a stand-alone wind power system with battery/supercapacitor hybrid energy storage. A stand-alone wind power system mainly consists of a wind turbine, a permanent magnet synchronous generator, hybrid energy storage devices based on a vanadium redox flow battery and a supercapacitor, an AC/DC converter, two bidirectional DC/DC converters, a DC/AC converter and a variable load. Several control strategies for the stand-alone wind power system are involved such as a maximum power point tracking (MPPT) control, a vanadium redox flow battery charge/discharge control and a supercapacitor charge/discharge control. The proposed MPPT control combines a sliding mode control with an extreme search control to capture maximum wind energy. This strategy avoids the necessity of measuring wind velocity, obtaining models or parameters of the wind turbine and calculating the differentials of the power generated from the wind power system and from the speed of the generator. The battery charge/discharge control maintains a constant DC bus voltage. When the battery charging/discharging current reaches the setting threshold, the charge/discharge control of the supercapacitor is triggered to limit the charging/discharging current of the battery. The simulation results show that the proposed method can rapidly respond to variations in wind velocity and load power.     

生态工程建设背景下贵州高原的植被变化及影响因素分析

基于MODIS-NDVI和气象数据，运用趋势分析、偏相关分析和残差分析等方法，对生态工程建设背景下贵州高原的植被变化及影响因素进行分析，并定量探讨气候因素与人类活动对植被变化的影响。结果表明：(1)2000~2016年期间，贵州高原植被NDVI在空间上呈东高西低的分布特征，高值分布于野生动植物及自然保护区等，低值分布于湿地保护工程区。NDVI总体呈上升趋势，湿地保护工程区、退耕还林工程区等植被覆盖上升速率较快，野生动植物及自然保护区呈略微的下降趋势。(2)植被改善区域(83.74%)分布于研究区边缘及西北部，退化区域(16.26%)分布于研究区中部和东南部，其中退耕还林还草工程区植被改善最为明显，野生动植物保护及自然保护区和速生丰产工程区改善效果较差。(3)从气侯因素分析来看，气温和降水在总体上与NDVI均呈正相关，气温对贵州高原植被生长的影响大于降水。(4) 从人类活动分析来看，人类活动对植被的建设作用强于破坏作用，人类活动正作用（76.68%）主要分布于西北部，负作用（23.32%）集中分布于东南部。植被覆盖增加是气候因素和人类活动共同作用的结果，人类活动对植被的贡献率为75.53%，气候因素为24.47%。