膜生物反应器在汽爆稻草秸秆酶解中应用研究

以汽爆稻草秸秆为原料,通过将几个酶解罐串联来提高最终还原糖浓度.考察了酶浓度,酶解单元组成以及稀释率对汽爆稻草秸秆酶解的影响.结果表明,最佳条件为:20FPU/g,酶解单元由4个酶解罐组成,稀释率为0.075/h.在此条件下,酶解时间为24h时,与传统批次酶解相比,汽爆稻草秸秆总转化率从18%～21%提高到39.5%.与只有1个酶解罐的膜反应器相比,每g底物还原糖产量从0.25g提高到0.4g,最终所得还原糖的平均浓度从4.56g/L提高到27.23g/L.     

地铁车站暴雨内涝应急响应投入策略研究*

为准确高效地开展地铁车站暴雨内涝应急响应活动,增强应对暴雨内涝灾害的救援能力,采用SHEL系统模型识别响应效能影响因素,分析各影响因素之间的相互作用机制,研究如何协调各个因素的投入比例,以达到响应效能最优,利用Vensim软件,结合成都地铁11号线相关数据进行模拟仿真。研究结果表明:应急响应活动存在明显阶段性特征,应急响应活动前期应保证救援人员快速到场,中期应特别注重提高救援指挥机构决策效率,后期更应关注硬件配置,且在应急响应活动全过程中持续保证人员与其他各界面的动态匹配。研究结果可为应对暴雨内涝灾害提供参考。     

Integrated toxicity assessment of DEHP and DBP toward aquatic ecosystem based on multiple trophic model assays

Environmental Science and Pollution Research - To comprehensively understand the toxic risks of phthalates to aquatic ecosystems, we examined the acute toxicity of di-(2-ethylhexyl) phthalate...     

Two-tier Haddon matrix approach to fault analysis of accidents and cybernetic search for relationship to effect operational control: a case study at a large construction site.

The Haddon matrix is a potential tool for recognizing hazards in any operating engineering system. This paper presents a case study of operational hazards at a large construction site. The fish bone structure helps to visualize and relate the chain of events, which led to the failure of the system. The two-tier Haddon matrix approach helps to analyze the problem and subsequently prescribes preventive steps. The cybernetic approach has been undertaken to establish the relationship among event variables and to identify the ones with most potential. Those event variables in this case study, based on the cybernetic concepts like control responsiveness and controllability salience, are (a) uncontrolled swing of sheet contributing to energy, (b) slippage of sheet from anchor, (c) restricted longitudinal and transverse swing or rotation about the suspension, (d) guilt or uncertainty of the crane driver, (e) safe working practices and environment.     

Fe-MCM-41催化臭氧氧化间甲酚废水

首次应用Fe-MCM-41催化臭氧氧化间甲酚废水.研究了铁的掺杂质量分数、催化剂质量浓度和底物质量浓度对间甲酚转化率和TOC去除率的影响,并采用XRD、H2-TPR、穆斯堡尔谱、BET对催化剂的结构性质进行表征.结果表明,铁的掺杂质量分数对Fe-MCM-41在催化臭氧氧化间甲酚中的活性具有较大影响,最佳掺杂质量分数为4.4%.随着铁掺杂质量分数的提高,介孔分子筛的结晶度减弱,介孔结构晶面间距减小,比表面积、孔容、平均孔径整体上呈下降趋势,Fe在介孔分子筛表面仅以γ-Fe2O3形式存在,且催化剂具有良好的铁磁性和稳定性.臭氧在反应中既有直接氧化作用也有间接氧化作用,且二者比近似为1∶1.在模型废水原始p H值条件下,使用Fe掺杂质量分数为4.4%的催化剂,当间甲酚初始质量浓度为500mg·L-1,催化剂质量浓度为0.1 g·L-1时,30 min内间甲酚转化率为100%,TOC去除率为26.8%.     

Evaluation of ionic fluids as lubricants in manufacturing

Ionic fluids are liquid salts that have been investigated for a number of applications, including catalysis, their use as solvents and electrically conducting fluids. Chemically, they consist of ionically bonded species, and depending on the cation and anion, can be extremely valuable in the chemical processing industry. Another characteristic that makes them useful is a high viscosity and good lubrication properties. This paper examines a number of ionic fluids, and determines their suitability as lubricants. This involves determining rheological properties, including viscosity and high-pressure viscosity, generally using a Barus law. In addition, their traction behavior is measured to evaluate their lubricating properties. Since metalworking fluids (and lubricants in general) are used in non-isothermal situations, the thermal conductivity of these fluids have also been measured.     

海洋混凝土结构表面防护涂料环境适应性评价研究进展

综述了岛礁混凝土结构表面防护涂料海洋环境适应性评价（老化）研究进展,对表面防护涂料海洋环境适应性评价中试验设计、控制因子设定、试验方法选择、评价指标确定等环节中存在的问题进行了讨论,认为只有在认真梳理单环境因子对涂料作用机理的基础上,对它们进行合理设定,才能有效提高加速试验结果和自然暴晒老化试验结果的相关性。     

Novel cationic polyamidine: Synthesis, characterization, and sludge dewatering performance

In this study, a new and facile route was employed for synthesis of polyamidine with abundant cations and attractive five-membered ringlike structural unit. N-vinylformamide and acrylonitrile copolymerized firstly to form intermediates, and the intermediates were processed with hydrochloric acid to produce polyamidine. A series of polymerization conditions (e.g. polymerization time, temperature and dosage of initiator) were optimized through productivity, viscosity and cationic degree as evaluation. SEM analysis illustrated that the amidinization process could reduce the size of spaces between molecular and created compact structure, which would contribute to good flocculation performance and high viscosity. FT-IR, XPS and NMR spectra presented a rather clear structure of polyamidine. 34.3% of sludge was sedimentated through the flocculation of polyamidine in the early stages. In contrast, only 6.8% of sludge was sedimentated by polyacrylamide. The moisture content in dehydrated floc could be reduced to 77.7% when 60 mg/L polyamidine was added. These results demonstrated that the polyamidine showed a great potential in the practical application of sludge dewatering.     

喀斯特不同坡位圆果化香的生理与形态特征比较

以喀斯特不同坡位的圆果化香为研究对象,测定上坡和中坡的土壤理化性质、圆果化香叶片的生理生化以及形态指标,研究不同坡位下圆果化香种群的水分调控、光合能力和形态特征的适应性差异。结果表明:(1)土壤含水量中坡比上坡高出94.73%,土壤有机质含量高出81.96%;土壤有效磷含量中坡高于上坡,全氮和全钾含量在两个坡位相差不大。(2)叶片净光合速率(Pn)日变化在上午9:00~11:00和下午13:00~16:00时中坡高于上坡,在"光合午休"时略低于上坡;Pn在中坡10时达到全天最高值7.53μmol·m~(-2)·s~(-1),而上坡在11时达到全天最大值7.03μmol·m~(-2)·s~(-1);叶片蒸腾速率(Tr)日变化在9:00~12:00中坡高于上坡,在12:00~15:00低于上坡。(3)圆果化香在中坡的叶片叶绿素a、b和总叶绿素含量分别比上坡高74.35%、80.89%、76.57%,丙二醛含量中坡小于上坡。(4)圆果化香叶片的平均长、宽、叶面积、叶片干重均为中坡大于上坡,而比叶面积上坡大于中坡;球果直径在中坡为2.65±0.16cm,比上坡大31.84%,球果的平均种子数量比上坡多27个。综合而言:由于坡位的差异,上坡土壤养分比中坡低得多,不能很好地供给植物生长;上坡圆果化香在水分输入方面不及中坡,而在水分输出方面高于中坡且调控不及时和不合理;在一天的光合作用中,中坡能积累更多的光合产物。