不同温度区间内污泥热解气固相产物特征

对城市污水污泥（简称污泥）进行工业分析和热重分析,考察污泥的基本组成和热重特性;采用气相色谱（GC）检测了不同热解温度区间内污泥热解生成的气体产物成分,并利用SEM和BET分别分析了不同热解终温下裂解炭的形貌特征和比表面积。结果表明：污泥热解可以分为水分析出阶段、挥发分析出阶段和焦炭化阶段;不同热解温度区间内污泥热解气体产物的组成有很大差别,热解温度350℃后H₂在热解气中的含量快速增加,CH₄含量在350～450℃时达到最大值,而CO主要在热解温度为350～750℃时生成,CO₂含量随着热解温度的增加迅速下降;随着热解终温的不断升高,裂解炭结构变得越来越疏松,比表面积也随之增大,750℃达到最大值55 m²·g^-1。     

Preparation of B<Subscript>4</Subscript>C-ZrB<Subscript>2</Subscript>-SiC eutectic ceramics by arc melting method

The B₄C-ZrB₂-SiC ternary composites with super hard and high toughness were obtained by arc melting in argon atmosphere. Microstructures were observed by SEM, and phase compositions were analyzed by XRD. The hardness and fracture toughness of ternary composites are 28 GPa and 4.5 MPa·m^1/2. The eutectic mole composition is 0.39B₄C-0.25ZrB₂-0.36SiC, and the eutectic lamellar microstructure is composed of B₄C matrix with the lamellar ZrB₂ and SiC grains.     

Effect of pre rigor stretching on beef tenderness development

The objective of this study was to determine effects of pre rigor stretching on beef tenderness development. Beef loins (M. longissimus dorsi; n=24) were assigned to either stretching or non-stretching treatments and aged for 14days at -1.5°C. Sarcomere length, shear force, water-holding capacity and proteolysis were determined for the loins at 1, 7 and 14days of ageing. Stretching increased the length of the loins by 33% resulting in a trend of increasing sarcomere length (P=0.19). However, no significant differences for shear force values, purge, drip and cooking losses between treatments were found. Shear force values decreased with ageing times (P<0.05). Western blot assay found that stretching did not affect the extent of desmin degradation. The findings from the present study suggest that pre rigor stretching with the current increase in length will not contribute to tenderness improvement of the beef loins.     

脱墨浆高白度漂白初步研究

通过对脱墨浆(主要是旧新闻纸脱墨浆)漂白的研究,探求获取高白度漂白脱墨浆的途径.结果表明,采用螯合剂预处理的H2O2-FAS两段漂白效果优良,白度增值达到11.9%ISO,浆料最终白度可达66.6%ISO.     

封闭水循环的发展前景

近年来，新纸机的设计车速成倍增加。随着对纸产品质量要求的提高和对二次纤维利用的增加，对过程中水的质量要求也就更高。     

基于层次分析法的智能电表器件选型

智能电表是智能电网的终端,它除了具备传统电表基本的计量功能之外,为了适应新能源与智能电网的使用,还具备通信功能、故障预测、相位检测等智能化功能。但是,关于智能电表的基本核心器件的选型,目前还没有统一的标准,基于此,本文提出一种基于层次分析法的对智能电表元器件选型方案,该方案依据智能电网的发展需求和业务特征,具体分析了智能电网对智能电表的功能需求,并分别针对智能电表具体功能模块的需求特性设置准则层,从而选择出该智能电表所需最优的元器件,为智能电表元器件选型提供科学化依据,支撑智能电网的发展。     

Bacterial Community of Koumiss from Mongolia Investigated by Culture and Culture-Independent Methods

The bacterial community of fermented horse milk (koumiss) from Mongolia was studied using three methods: cultivation, direct identification by 16S rRNA clone library and denaturing gradient gel electrophoresis (DGGE). Ninety-eight strains were isolated by traditional cultivation and 61 of those were randomly selected for further identification by 16S rRNA gene sequencing. The strains were dominated by lactic acid bacteria (LAB; six different lactobacilli), Acinetobacter, Bacillus and Psychrobacter. Construction of the clone library analysis revealed that 16S sequences of 220 clones, genus Lactobacillus was dominant, but Streptococcus thermophilus, Acetobacter pasteurianus and uncultured clones were also detected. Ten unique bands were sequenced from the DGGE and revealed: Lactococcus lactis, Lactococcus lactis subsp. lactis, Clostridium acidurici, Acinetobacter johnsonii, Dickeya sp., Enterobacter sp., Pseudomonas sp., Raoultella sp., and Ruminococcus sp.. In vitro growth inhibition of three human pathogens, Escherichia coli, Enterobacter sakazakii and Staphylococcus aureus by 14 culturable bacteria displayed that only three of the isolates tested inhibit growth of E. sakazakii while most of the other bacteria delayed growth of the target bacteria.     

海上油田电脱分离器结构设计研究

作为原油净化处理的关键步骤,电脱分离效果的好坏直接决定原油能否达到深加工或销售的要求。对电脱分离器的机理和结构进行了详细分析,并针对海上油田的特殊工况,提出了设计海上油田电脱分离器时应考虑的因素和设计方法。     

共振式水泥混凝土路面破碎车共振频率和振幅的控制研究

基于共振式水泥混凝土路面破碎车共振机构的载荷分析,给出了其共振频率和振幅的模型。针对共振机构电液比例控制系统的非线性和不确定性问题,建立了基于比例泵控马达的频率控制数学模型,设计了自适应反推滑模的频率控制算法,针对系统模型中的不确定项,给出了各参数项的自适应律,基于Lyapunov函数,证明了频率输出跟踪的渐近收敛。仿真和车载实验结果表明,该方法具有较好地频率跟踪性能,能满足共振式水泥混凝土路面破碎车的施工作业要求。     

Effect of cotton cellulose manufacturing conditions on process quality indexes

The possibility of fabricating cotton cellulose from linters with a process scheme which provides for altering the order of the stages of alkaline and acid cooking was investigated. The molecular and process indexes of the cellulose obtained were determined. The possibility of fabricating cotton cellulose with a satisfactory content of α-cellulose, degree of polymerization, and reactivity was demonstrated.