高压共轨柴油机高海拔全负荷标定

高原标定是高压共轨柴油机开发过程中的重要环节.利用高海拔(低气压)标定试验系统进行了高压共轨柴油机不同海拔下的全负荷标定试验,研究了最佳喷油参数随海拔的变化,并进行了高压共轨柴油机不同海拔下的功率试验.研究结果表明,最佳循环喷油量随海拔的增加而减小,海拔每升高1 000,m,循环喷油量下降2%～4%;中高转速下最佳喷油提前角和轨压随海拔的增加而增大.海拔每升高1 000,m,最大转矩降低2.8%,标定功率下降2.9%.不同海拔下柴油机速度系数保持不变.不同海拔中高转速燃油经济性基本保持不变,低转速下燃油经济性恶化,海拔每升高1 000,m,低转速下燃油消耗率增加3.9%.     

铁法矿区地质灾害监测与评价

通过建立铁法矿区地质灾害监测网,对矿区现状的地质灾害进行了评价,查明了矿区的地质环境现状和主要地质灾害,提出了矿区采煤沉陷区治理规划方案,为开发煤炭资源提供了科学依据。     

Ammonia chemistry below 1400 K under fuel-rich conditions in a flow reactor

The oxidation of NH₃ under fuel-rich conditions and moderate temperatures has been studied in terms of a chemical kinetic model over a wide range of conditions, based on the measurements of Hasegawa and Sato. Their experiments covered the fuels hydrogen (0 to 80 vol%), carbon monoxide (0 to 95 vol%), and methane (0 to 1.5 vol%), stoichiometries ranging from slightly lean to very fuel rich, temperatures from 300 to 1330 K, and NO levels from 0 to 2500 ppm. A detailed reaction mechanism has been established, based on earlier work on ammonia oxidation in flames and on selective noncatalytic reduction of NO by NH₃. The kinetic model reproduces the experimental trends qualitatively over the full range of conditions covered, and often the predictions are in quantitative agreement with the observations. Using reaction path analysis and sensitivity studies, the major reaction paths have been identified. The comparatively low temperatures in the present study, as well as the presence of NO, promote the reaction path NH₃→NH₂→N₂ (directly or via NNH), rather than the sequence NH₃→NH₂→NH→N important in flames. The major conversion of fuel-N species to N₂ occurs by reaction of amine radicals with NO, in particular NH₂+NO. In the presence of CH₄, NO is partly converted to cyanides by reaction with CH₃. The mechanism is recommended for modeling the reduction of NO by primary measures in the combustion of biomass, since it has been validated under conditions resembling the conversion of early nitrogenous volatile species in a staged combustion process. It is also appropriate for studies of NO formation in the combustion of gas from gasifying coal.     

膨化硝酸铵的热分解动力学研究

利用热重法测得了普通工业硝酸铵和膨胀化硝酸铵的热重曲线,计算到了普通肖酸铵和膨化硝酸铵的热分解活化能,研究了普通工业硝酸铵和膨化硝酸铵的热分解反应机理和动力学方程。     

高氮量硝化棉的脱硝反应动力学研究(英文)

用实时测定凝聚相分解产物的固体原位反应池/快速扫描傅立叶变换红外光谱热技术研究了高氮量硝化棉(14.14%N)的脱硝反应动力学。该反应的动力学参数(活化能和指前因子)用改良的Coats-Redfern法计算。根据所得结果,提出了在403～465K温度范围内描述高氮量硝化棉脱硝反应的微分动力学方程。     

叶片前缘开缝对离心风机气动及噪声的影响研究

将前缘缝翼思想运用到离心风机中,研究了叶片前缘开缝设计参数对离心风机内部流场及其声辐射的影响规律。研究表明:叶片前缘开缝使气流通过狭缝得到加速,抑制后叶片吸力面边界层分离;同时,开缝设计使叶轮内部压力脉动明显减弱,降低离心风机气动噪声源强度,存在最佳开缝参数组合使离心风机流动与降噪效果达到最佳;设计工况下,当开缝位置L/C=0.30,前叶偏转角θ=4°,且前、后叶片最大相对厚度相等时,离心风机全压提高7%,效率提高2%,其远场噪声各测点总声压级平均下降3.5 dB。     

基于规范标准设计反应谱的参数敏感性分析

抗震设计反应谱是土石坝动力计算分析的主要依据,其中反应谱参数的合理确定是工程抗震安全分析的重要环节之一。基于《水工建筑物抗震设计规范》设计反应谱,依托某心墙堆石坝,初步探讨了反应谱参数对坝体动力反应及地震永久变形的影响。结果表明,增加地震动峰值加速度、增大动力放大系数最大值、延长反应谱特征周期均会使坝体的加速度反应和永久变形在一定程度上增大,由此对反应谱参数的选择提出了一些合理化建议。     

REACTION KINETICS PARAMETERS DESCRIBING DISPLACEMENT BY ACIDS OF STRUCTURAL METALLIC IONS FROM CLAY MINERALS

Chemical kinetics parameters describing reactions of naturally-occurring clay minerals with acids were determined using batch reaction and analytical techniques. Clay minerals included sodium montmo-rillonite, kaolinite, and illite, reacting with hydrochloric acid, nitric acid, and sulfuric acid. Two acid concentrations were examined at 50 and 70^°C. Displacement by acids of aluminum and magnesium from clays was found to follow pseudo-first order kinetics. Data analysis verified the batch reaction technique for determining kinetics parameters of acid-clay reactions and demonstrated acid neutralization by naturally-occurring clays. For reactions of sodium montmorillonite with hydrochloric acid, nitric acid, and sulfuric acid, reaction rate coefficients for displacement of aluminum ranged from 1·73 × 10^-4 kg/mol-hr at 50^°C to 3·02 × 10^-3 kg/mol-hr at 70^°C. Displacement of magnesium from sodium montmorillonite by these acids occurred at rates ranging from 3·68 × 10^-4 kg/mol-hr at 50^°C to 1·12 × 10^-2 kg/mol-hr at 70^°C. Activation energies for displacement by acids of aluminum from sodium montmorillonite were calculated to range from 31,000J/mol to 112,000J/mol, while activalion energies for displacement of magnesium from sodium montmorillonite ranged from 36.000 J/mol to 103,000 J/mol. For reactions of illite with acids, reaction rate coefficients for displacement of aluminum were determined to be 1·45×10^-4Kg/mol-hr at 50^°C to 1·7×10^-3kg/mol-hr at 70^°C. Displacement of magneisum by acids from illite occurred at rates from 6·06 × 10^-4 kg/mol-hr at 50^°C to 5·97 × 10^-3 kg/mol-hr. Activation energies for reactions of acids with illite ranged from 33,000 J/mol to 62,000 J/mol for displacement of aluminum and from 9,400 J/mol to 29,000 J/mol for displacement of magnesium.     

单级膜生物反应器处理生活污水的研究

对单级膜生物反应器（MBR）处理生活污水进行了研究,考察了在四种工况下反应器对COD和氮的去除效果及其影响因素。试验结果表明：反应器对COD具有很好的去除效果,去除率在93％以上;对于氮的去除,反硝化是该工艺的关键控制步骤,通过改变运行工况和增加污泥浓度,使NH^＋4-N的去除率达90％以上,TN的去除率达83％以上。     

低酸催化水解稻草制备腐植酸的工艺研究

试验采用低酸催化水解工艺,从稻草中提取腐植酸.根据单因素试验设计,通过测定水解过程中稻草纤维素转化率和腐植酸产率的变化指标,来寻求较佳工艺参数.结果表明,初始阶段反应条件为温度220℃、0.1%硫酸溶液、固液比1∶12、压力4 MPa、转速300 r/min、时间20 min,将反应釜的反应条件调整为温度70℃、转速3...