固定化微生物脱除工业酸性废气中H_2S的研究

以H 2软性填料作为氧化亚铁硫杆菌的固定化载体 ,构成了固定床生物反应器。在一定操作条件下 ,考察了固定床生物反应器对Fe2 +的氧化速率 ,最大可达 7.6 7g/ (L·h)。并对固定床生物反应器运行中在载体表面形成的络合物进行了研究 ,X射线衍射证明此络合物为黄钾铁矾 [KFe3(SO4 ) 2 (OH) 6]。     

Modeling for local dynamic behaviors of phenol biodegradation in bubble columns

A coupled three-dimensional (3-D) model, combining hydrodynamics with biochemical reactions, was developed to simulate the local transient flow patterns and the dynamic behaviors of cell growth and phenol biodegradation by yeast Candida tropicalis in the bubble-column bioreactor, using the computational fluid dynamic (CFD) method. In order to validate this proposed model effectively, the validation of the local hydrodynamic characteristics of the gas-mineral salt solution (gas-liquid) two-phase system, with the phenol concentration of 1200 mg/L, and with the absence of cells, was performed in a square-sectioned bubble column bioreactor using the LDA system and conductivity probe. Furthermore, the validation of phenol biodegradation behaviors by yeast Candida tropicalis at different initial concentrations of phenol and cell was also carried out in the above bubble-column bioreactor. The results indicated that the model simulations had a satisfying agreement with the experimental data. Finally, the local instantaneous flow and phenol biodegradation features including gas holdup, gas velocity, liquid velocity, cell concentration and phenol concentration inside the bioreactor were successfully predicted in different-scale bubble columns by the proposed model. © 2006 American Institute of Chemical Engineers AIChE J, 2006     

Cr对低碳Si-Mn系TRIP钢组织与力学性能的影响

主要研究了Cr对低碳Si-Mn系TRIP钢组织与力学性能的影响。首先利用Formastor-F型膨胀仪测定了含Cr和不含Cr两种低碳钢的连续冷却转变(CCT)曲线,分析指出了Cr对连续退火工艺的潜在影响;然后采用Gleeble-3800热/力模拟试验机对两种钢的薄板试样进行了连续退火模拟实验,并通过拉伸试验测定了力学性能;最后采用金相、扫描电镜、X-射线衍射分析等技术考察分析了两种钢的显微组织。结果表明:含Cr的TRIP钢的组织比较细小,铁素体晶粒近似等轴分布;两种TRIP钢的残余奥氏体含量相近,但含Cr钢的残余奥氏体中的含碳量较高。分析认为这是由于含Cr钢在热轧阶段较易生成细小的组织,而在热处理阶段则抑制贝氏体的生成,最终获得稳定的残余奥氏体。     

食物营养规划培训效果追踪和影响因素分析

本文采用调查问卷,追踪访问了参加食物营养规划培训班的人员一年后的工作开展、培训知识掌握和应用情况.结果表明,这些人员较好地掌握了培训知识,平均掌握率为70%,培训知识和技能应用率平均为46%;性别、年龄、技术职称和部门来源等对培训知识掌握和应用有一定的影响.     

溶胶-凝胶法制备Li（MoO4）2：Eu及表征

用溶胶-凝胶法制备了平均粒径为2～3μm的小颗粒、高亮度的Li（2-x）（MoO4）2：Eu系列钼酸盐红色荧光体。用XRD、SEM、粒度分析和分子荧光光度计对荧光体进行了表征和研究。常规的固相反应合成Li（2-x）（MoO4）2：Eux系列红色荧光粉需要在900℃以上的高温才能够形成均一的固溶体，而采用溶胶-凝胶法制取，在700℃就可以形成均一的单相Li（2-x）（MoO4）2：Eux，在750℃就可得到发光亮度最高的荧光体。其亮度是常规固相反应于900℃制得的荧光体的124％。采用溶胶-凝胶法制取Li（2-x）（MoO4）2：Eux系列，可以在相当宽的实验条件范围内得到小粒径、窄分布和高亮度的荧光体，具有良好的颗粒形貌。     

实用户外视频监控异常检测策略

树枝叶等植物的晃动是造成户外监控背景复杂性的主要因素。该文提出一种基于视频分析的运动对象检测策略，利用快慢双背射模型检测运动变化像素，并通过邻域像素的棚关性检测消除虚假运动对象。实验表明此算法对户外监控不但速度快而且检测效果理想，满足实用化要求。     

Is electrogastrography a substitute for manometric studies in children with functional gastrointestinal disorders?

We performed simultaneous fasting and fed antroduodenal manometry and EGG in 25 children with functional bowel disorders. Three patients (12%) had an uninterpretable EGG. The manometric studies showed severe neuropathy in six patients; milder neuropathic changes in five patients; postprandial hypomotility in one patient; myopathy in four patients, and normal motility in the remaining six patients. The percentage of tachygastria time (frequency > 3.5 cycles/min) was higher in the patiens with mild (44.1 +/- 15.8%) and severe (48 +/- 19.1%) neuropathy than in the patients with myopathy (20 +/- 16.2%, P < 0.05) or with normal motility (23 +/- 13.3%, P < 0.05). There was a considerable overlap in the percentage of tachygastria and total arrhythmia time among the different study groups. The ratio of post- to preprandial power was significantly higher (2.5 +/- 0.07) in children with normal motility than in the other patients groups. Every child with total arrhythmia time < 35% and a ratio of post- to preprandial power > 2.4 had normal manometry. In summary, EGG differentiated groups of children with normal manometry from others with neuropathic or myopathic changes, but in a minority of patients the study was not interpretable and there was overlap in EGG results between children with normal and abnormal manometry.     

有环境约束时完成一族跟踪任务的力控制

本文为工业机器人提出了一种极点配置控制法，这种控制方法的优点有：一是它的积分作用消除了机器人的微小扰动和稳态误差；二是能任意设置系统的极点，因此能保证闭环系统的稳定性和规定状态变量的暂态响应；三是加入了加速度反馈，抑制了由电枢电感所引起的机械手的振动，最后，给出了ＰＵＭＡ５６２机器人的计算机仿真和实验结果验证了此控制法的有效性。     

Dopamine D2 receptor signaling via the arachidonic acid cascade: modulation by cAMP-dependent protein kinase A and prostaglandin E2

Recent studies have shown that, in Chinese hamster ovary cells transfected with D2-receptor cDNA, CHO(D2) cells, D2 agonists are potent in enhancing the release of [3H]arachidonic acid (AA) induced by stimulation of constitutive purinergic receptors or by application of Ca2+ ionophores. This facilitatory action is further amplified by the concomitant activation of D1 receptors, which per se have no effect on evoked [3H]AA release. Here, we review a series of experiments aimed at examining the molecular mechanism of this synergistic interaction. The results show that, in CHO(D2) cells: (a) application of 8-Br-cAMP or stimulation of constitutive prostaglandin (PG)E2 receptors augment the AA response produced by D2 agonists; (b) in CHO(D2) cells transfected with human beta 2-receptor cDNA, the beta-agonist, isoproterenol, produces a similar effect; (c) the potentiation of [3H]AA release produced by PGE2 and 8-Br-cAMP is prevented by overexpressing either a protein inhibitor of cAMP-dependent protein kinase (PKA) or a mutated form of pKA regulatory subunit incapable of binding cAMP; (d) mock-synergism is obtained in CHO(D2) cells overexpressing the catalytic subunit of PKA; (e) PGE2 is a major AA metabolite in stimulated CHO(D2) cells and its formation may contribute to the effect of D2 agonists on AA release. The results indicate that cAMP-induced activation of PKA represents a likely molecular basis for D1/D2 receptor synergism on AA release. They also suggest that additional membrane receptors, colocalized with D2 and positively linked to adenylyl cyclase, may exert a similar action. Furthermore, stimulation of PGE2 receptors by endogenously produced prostaglandin may participate in AA signaling at the D2 receptor, by providing a paracrine positive feedback loop.