处理城市污水新技术：同步硝化-反硝化单级生物脱氮技术

本市环境保护科学院开发出同步硝化-反硝化单级生物脱氮技术,被列入2003年度天津市百项科技成果。该成果分离筛选了多株硝化-反硝化菌、脱氮硫杆菌,并对菌种的复配形成一个有效的复合菌群。课题组研究了硝化菌群在不同材质上的吸附特性,利用改性聚丙烯和活性碳开发了一种复合式载体。该活性载体可有效提高脱氮效率,增加系统抗冲击负荷的能力,并且可提高自然水体中脱氮功能菌群的生物量,为封闭水体及城市景观水体的富营养化控制提供了一种简单有效的方法。利用该实验室筛选的菌种,开发了接触氧化反应器和加载体的膜生物反应器。两种反应器均…     

固体超强酸SO_4~(2-)/Fe_2O_3催化N,N-二乙氨基乙醇与含芳香环的羧酸的酯化反应

用固体超强酸SO2-4/Fe2O3催化N,N 二乙氨基乙醇与9个含芳香环羧酸的酯化反应,合成了9个相应的酯,产率在75%～95.6%之间.讨论了不同的固体超强酸及催化剂用量,溶剂和反应温度,反应时间等因素对酯化产率的影响.实验结果表明:当催化剂用量占反应物总量的3.4%～3.8%,溶剂为二甲苯,反应温度140℃,反应时间6h的条件下,酯化产率最高.     

具有第类功能性反应的捕-食系统的定性分析

研究了捕食者无密度制约,食饵有密度制约的具有Holling第 类功能性反应的捕-食系统的定性行为.在食饵有(或无)常数放养率的情况下,利用Pioncare-Bendixson环域定理及极限环的唯一性定理,对此系统作了完整的定性分析.结果表明,在一定条件下,当正平衡点稳定时,系统为全局渐进稳定的;当正平衡点不稳定时,系统存在唯一的极限环.     

考虑位置随机性的固体颗粒起动临界流速研究

水平井钻井、砾石充填及冲砂等作业都涉及到固液两相流动的固体颗粒起动问题。液流作用下颗粒的起动与其在床面上的沉没位置有关,沉没位置的随机性导致颗粒起动的随机性。引入颗粒无因次沉没度随机变量,将其概率密度视为均匀分布,考虑颗粒重力、水流推力、上举力、水柱静压力和粒间粘结力以及各力臂与沉没度的关系,通过力矩平衡分析,建立了考虑颗粒起动随机性的临界流速公式。结合无因次沉没度的概率分布函数,在临界流速与颗粒起动标准之间建立了定量关系,为一定颗粒起动标准下的临界流速计算提供了实用公式。用得出的公式进行了实例计算,并将计算结果与已有试验结果进行了对比,在0.001～10mm粒径范围内两者吻合较好。     

Swelling Studies of Chitosan-Gelatin Films Cross-Linked by Sulfate

0　IntroductionChitosanisadeacetylatedderivativeofchitin ,containinginitsstructure glucosamineandacetylglucosamine joinedthroughβ (1→ 4 )linkages.ItisinsolubleinwaterandcommonorganicsolventsbutsolubleatapHunder 6 .5acidicmedia.Duetoitsexcellentbiodegradableandbiocompatiblecharacter,chi tosanhasbeenexaminedextensivelyinthepharmaceuticalindus tryforitspotentialinthedevelopmentofdrugdeliverysys tems[1 ,2 ] .Gelatinisabiodegradablepolymerofwidesafety ,pro ducedfromcollagen ,themostabundantprote…     

非汉字符号"混合序列的强大数律

讨论了一类较广泛的~混合序列的收敛性质,获得了与独立情形一样的三级数定理等收敛性质,并由此得到与独立情形一样的Kolmogov强大数律的充分条件.     

γ-干扰素诱导沙眼衣原体感染细胞酪氨酸激酶活化的研究

目的探讨IFN-γ诱导的沙眼衣原体感染细胞信号转导中酪氨酸激酶活化。方法采用IFN-γ作用于沙眼衣原体感染的McCoy细胞，用免疫印迹法检测信号蛋白酪氨酸激酶磷酸化的诱导活化，并应用酪氨酸激酶特异性抑制剂genistein拮抗IFN-γ诱导的酪氨酸激酶磷酸化。结果IFN-γ可以在短时间内引起沙眼衣原体感染细胞内的蛋白质酪氨酸激酶磷酸化。磷酸化程度随时间延长而改变，在15min时磷酸化程度最高，以后逐渐减弱。Genistein可抑制IFN-γ诱导的酪氨酸激酶磷酸化；随着浓度增大，抑制作用有所增加。结论IFN-γ诱导沙眼衣原体感染细胞酪氨酸激酶活化。     

基于径向基函数神经网络的滚动轴承故障模式的识别

The impacts of different groove shapes, numbers, and angle of friction dish on transmitting torque, speed, push pressure in wet speeding clutch are discussed in this paper. Since the wet speeed governing clutch works within hydrodynamic lubrication mixture lubrication. boundary, lubrication and contact situation, the oils combining with a-hydrocarbon or polyester are getting widely used as lubricant.The power-law fluid model with Patir-Cheng average flow model, GT asperity contact model and oil film inertia are applied for average Reynolds equation setting, In order to investigate the relationship between average push pressure within hydrodynamic lubrication and mixture lubrication, average transmitting torque and output speed, the numeral calculation and analysis are presented. According to calculation, it is found that the groove shape, groove angle and groove numbers affect the average transfer torque and push pressure with the speed rate.     

Leaching Mechanism of Complicated Antimony-Lead Concentrate and Sulfur Formation in Slurry Electrolysis

Anodic reaction mechanism of complicated antimony-lead concentrate in slurry electrolysis was investigated by the anodic polarization curves determined under various conditions. The main reactions on the anode are the oxidations of FeCln^(2-n) . Though the oxidation of jamesonite particle on the anode can occur during the whole process, it is less. With the help of mineralogy studies and relevant tests, the leaching reaction mechanism of jameson[to and gudmundite during slurry electrolysis was ascertained. Because of the oxidation reaction of FeCl3 produced by antimony-lead concentrate itself, the non-oxidation complex acid dissolution of jameson[re, the oxidation complex acid dissolution of gudmundite, and the oxidation of air carried by stirring, the leaching ratio of antimony reaches about 35% when HCl-NH4Cl solution is used to leach antimony-lead concentrate directly. So when the theoretical electric quantity is given to oxidation of antimony in slurry electrolysis, all of antimony, lead and iron containing in antimony-lead concentrate, are leached. The formation of sulfur is through the directly redox reaction of Fe^3 and jameson[re. The S^2- in jamesonite is oxidized into S^0 , and forms the crystals of sulfur again on the spot. The redox reaction of Fe^3 and H2S formed by non-oxidative acid dissolution of jamesonite is less.     

Velocity Distribution of Slurry in Horizontal Pipe When Solid Particles Sliding

Based on the laws of momentum conservation and impulse in accelerating process, the distribution on speed of ununiform slurry flow in a horizontal pipe was studied. According to the momentum change of solid particles and conveying liquid of slurry flow during accelerating, and some effect factors, the relationship between the speed of solid particles and the speed of conveying liquid was obtained.When dealing with the friction between sliding solid particles and pipe, it is pivotal to reasonably distribute component of friction to each solid particle. The friction coefficient between solid particles was obtained by forces analysis and theoretic calculation, and can be used to calculate the friction force on every solid particle. The effect of friction on speed of ever), solid particle was investigated through the impulse law. The result is more accurate than that by using uniform friction on solid particles. It is completely new method to use above theory to get solid particles speed distribution, conveying liquid speed distribution and slurry speed distribution.