关于我国北方沙化农牧混合区的可持续发展问题

东起柯尔沁草地南缘,西至鄂尔多斯台地南缘的北方沙化农牧混和地带,正在面临着草地沙漠化的严峻挑战。本文从如下角度分析了影响该地区可持续发展的因素:农—林—牧的资源配置,农民对沙地草地改良技术的消极态度及背后隐藏的理性原因,经济政策和市场机制,土地的制度安排,农民在治理沙化草地中的潜在作用等。然后,得出了基本的结论和建议。     

REGIONAL WATER SUPPLY PLANNING BY INTERACTIVE SYSTEMS ANALYSIS1

Abstract: This paper describes an interactive data and model generator that is intended to bridge the gap between the water resource enginner and planner and the mathematical progrmming systems approach to regional water supply planning. The optimization objective is to minimize total annual cost with respect to capital investment and operation and maintenance costs. The matrix generator formulates the necessary hydrologic, demographic and programming problem for system optimization. The interactive program guides the user through the input and optimization segments, totally eliminates the chore of manually structuring the model matrix aides in eliminating errors, and allows use by planners without skill in mathematical programming.     

国外清洁汽油生产技术进展

介绍了国外清洁汽油生产技术进展情况，指出清洁汽油的生产与技术开发是我国炼油工业的发展方向。     

受限空间火灾轰燃过程的模拟实验研究

研制一种重现火灾轰燃的化学燃料和氧化剂的混合燃料，通过调整燃料的配方，可实现模拟控制火灾轰燃的温度和烟气产生量；实验研究了火灾轰燃过程烟气参数的变化规律，说明建筑火灾烟气运动的场-区-网模拟模型是合理的，分析了火灾过程中烟气的产生、运动、回流、下沉现象物理机制，指出在受限空间火灾救灾过程中应注意的问题。     

燃油箱系统静电实验研究

在飞机燃油箱内填充网状聚氨酯泡沫材料(以下简称“聚氨酯泡沫”)是一种十分有效的被动抑制损伤的防爆技术。但在飞机地面加油时,燃油与聚氨酯泡沫的高速冲刷与摩擦会产生静电并可能发生静电荷的积聚而使燃油带上高的静电电压,极有可能发生静电火花放电,威胁飞机安全。为了探寻填充聚氨酯泡沫燃油箱系统的静电电压积累规律,设计了简化的实验装置和测量系统,以几种较快的流速进行静电循环冲刷实验,并分类进行各项实验数据的整理和分析。通过Origin7.0软件采用非线性最小二乘法拟合(Levenbergmarquardt算法),编制了自定义参数初始化函数,完成了实验公式的参数求解。该参数估计不受人工干预,且拟合精度较高。通过实验和计算得到了填充聚氨酯泡沫燃油箱系统的静电电压积累数学表达式,基本符合静电电压经典物理公式。     

大型公共场所人员疏散过程及引导作用研究

通过对已建立的大型公共场所人员疏散模型中的疏散速度和疏散时间进行改进，进一步模拟了同一避难场景中的不同人员按照各自的意志分别采取最短距离行为模式、进出一致行为模式和完全从众行为模式的，更接近现实的混合疏散行为模式；并在此基础上引入了引导人这一要素，通过设置引导人的数量、位置及其影响范围，对疏散过程中的引导作用进行了详细探讨，以期为充分发挥引导作用，从而提高疏散效率的避难对策提供依据。     

Efficient degradation of lube off by a mixed bacterial consortium

A laboratory study was performed to assess the biodegradation of lube oil in bio-reactor with 304# stainless steel as a biofilm carrier.Among 164 oil degrading bacterial cultures isolated from oil contaminated soil samples, Commaonas acidovorans Pxl, Bacillus sp.Px2, Pseudomonas sp. Px3 were selected to prepare a mixed consortium for the study based on the efficiency of lube oil utilization.The percentage of oil degraded by the mixed bacterial consortium decreased slightly from 99% to 97.2% as the concentration of lube oil was increased from 2000 to 10,000 mg/L. The degradation of TDOC (total dissolved organic carbon) showed a similar tendency compared with lube oil removal, which indicated that the intermediates in degradation process hardly accumulated. Selected mixed bacterial consortium showed their edge compared to activated sludge. Scanning electron microscopy (SEM) photos showed that biofilms on stainless steel were robust and with a dimensional framework constructed by EPS (extracellular polymeric substances),which could promote the biodegradation of hydrocarbons. The increase of biofilm followed first-order kinetics with rate of 0.216 μg glucose/(cm~2·day) in logarithm phase. With analysis of Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) combined with removal of lube oil and TDOC, mixed bacterial consortium could degrade benzene and its derivatives, aromatic ring organic matters with a percentage over 97%.     

回流比对投料A~2/O工艺脱氮除磷影响的中试研究

试验采用了投料A2/O脱氮除磷工艺在广州市某污水处理厂进行中试,考察了不同混合液回流比及污泥回流比对投料A2/O工艺脱氮除磷的影响。结果表明,混合液回流比对COD、TP和NH3-N影响较小,对TN的去除率影响较大,系统混合液回流比为200%时,系统处理效果最佳;污泥回流比对系统整体功能的影响较大,随污泥回流比的增大,各指标的去去除率随之增大,结合处理效果和能耗情况,污泥回流比为75%时系统效果最佳。     

碳氮源对光合细菌混合菌群产氢性能的影响

碳源和氮源是产氢光合细菌生长发育过程中不可缺少的营养物质,与光合细菌菌株产氢能力相关。以从花园土壤中富集分离出来的光合细菌混合菌群为研究对象,在血清瓶中于30℃下采用厌氧培养方式间歇培养8天,分别考察不同的碳源、氮源、碳氮源组合及其浓度变化对光合细菌产氢行为的影响。结果表明,碳氮源种类对光合细菌产氢能力有显著影响,与氮源相比,碳源对产氢量的影响更为显著,最佳碳源为葡萄糖,最佳氮源为草酸铵。最佳碳氮源组合为葡萄糖和谷氨酸钠组合,葡萄糖和谷氨酸钠浓度分别为3g/L和1g/L时,产氢量和最大产氢速率分别达41.35mLH2/(L-培养基)和0.328mLH2/(L-培养基·h)。研究结果为进一步探索产氢光合细菌生长的营养生理奠定了基础,对大规模培养条件的优化提供了依据。