某恒温间歇反应的热失控研究

为得到某恒温间歇反应冷却系统临界温度Tc并评估该反应体系的热危险性,基于间歇反应体系热参数的敏感性,探讨数值计算方法和选用4种反应热失控临界判据得到的不同Tc值。结果表明,数值计算方法得到了反应体系的Tc为31.7℃,Semenov判据、Sliding判据、Da/St判据得到的Tc值分别为10℃,17℃和27℃;无量纲绝热温升B给出的结论是,在允许的工艺温度范围内,该反应对任意的冷却系统温度都处于难以控制状态。数值计算方法及各判据得到的Tc的较大差异性说明各方法均有一定的局限性。在运用参数敏感性分析的基础上,结合风险矩阵图方法对系统冷却失效的热危险性进行评估,得到不同Tc下风险可接受、有条件接受及不可接受对应的参数范围的物料累积度Xac与最大反应速率到达时间θ间的关系。     

补充碳源对厌氧生物处理2,4,6-三氯酚的影响

利用半连续投料的驯化方法对３种不同来源的生物污泥厌氧降解２,４,６－三氯酚（２,４,６－ＴＣＰ）过程中补充碳源的影响进行了研究。结果表明,经过５０～６０ｄ的驯化,取自有机化工厂和造纸七厂的２种污泥的比降解速度（氯酚／ＳＳ）分别达到了０．６ｍｇ／（ｇ·ｄ）和０．２ｍｇ／（ｇ·ｄ）,而取自北京啤酒厂ＵＡＳＢ反应器的污泥的比解速率只有０．０３ｍｇ／（ｇ·ｄ）～０．０５ｍｇ／（ｇ·ｄ）。补充碳源对北京啤酒     

甲黄隆在有机溶剂中的光解

以中压汞灯为光源,研究了甲黄隆在甲醇和丙酮等有机溶剂中的光解动力学,结果表明均为一级反应。甲黄隆在甲醇中的光解速率与在水中相差不大,而丙酮可明显促进其光解。甲黄隆在甲醇中光解先断裂脲桥,生成磺酰胺和取代三嗪,磺酰胺继续光解生成苯甲酸甲酯和微量的硫酚。     

DAoPM与铬（Ⅵ）显色反应的研究

在磷酸介质中，Ｍｎ（Ⅱ）存在下，ＤＡｏＰＭ和铬（Ⅵ）反应生成橙色物，λｍａｘ＝４８０ｎｍ、ε＝２．２５＊１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，铬（Ⅵ）含量在０－５μｇ／２５ｍＬ内符合比尔定律，方法用于水样中铬（Ⅵ）的测定，结果满意。     

Prenatal diagnosis of tyrosinase-negative oculocutaneous albinism by an electron microscopic dopa reaction test of fetal skin

An electron microscopic DOPA reaction test of fetal skin was used for the prenatal diagnosis of tyrosinase-negative oculocutaneous albinism (OCA). The subject was a 34-year-old Japanese woman in her second pregnancy. Her first child, born in 1982, had been previously examined and confirmed to have tyrosinase-negative OCA. The parents requested a prenatal diagnosis and we sampled skin from the upper trunk of the fetus. On conventional electron microscopy, the development of melanosomes in interfollicular melanocytes had progressed no further than stage II. Fetal skin samples incubated with L-DOPA solution indicated a lack of tyrosinase activity and showed that the melanosomes had not progressed beyond stage II. In skin samples from the trunks of three Japanese fetuses aborted for other reasons at 19–20 weeks of gestation, most premature melanosomes were further melanized to stage IV after incubation with L-DOPA solution. A prenatal diagnosis of tyrosinase-negative OCA was made. The parents requested a termination and skin biopsies of the abortus confirmed the diagnosis. This study shows that tyrosinase is normally present in melanocytes of the fetal epidermis at 20 weeks' gestation, and that the electron microscopic DOPA reaction test of a fetal skin biopsy specimen is safe and practical, and provides reliable information for making a prenatal diagnosis of tyrosinase-negative OCA in the second trimester.     

PCR技术在环境微生物检测中的应用

多聚酶链式反应技术（ＰＣＲ）近年来已广泛应用于环境微生物检测中,与常规方法比较,它具有灵敏度高、特异性强及快王速简便等优点,本文简要介绍了ＰＣＲ技术的基本原理,ＰＣＲ应用于环境微生物检测的方法学及其应用现状与前景。     

食品企业污水中细菌的基因芯片快速检测技术

食品企业污水中含有各种无机污物和有机污物．其中夹带的致病菌将导致多种疾病的爆发和流行．严重威胁着人类的健康。传统的细菌分离、培养和鉴定技术操作繁琐且耗时长（一般需4～7d）。为了快速．准确地检测食品企业污水中存在的细菌，建立了一种采用基因芯片技术对食品企业污水中常见细菌检测和鉴定的实验方法（需时4h）。实验中设计了8对特异引物并成功分成2组混合引物进行多重PCR反应：BI物Ⅰ为Kp＋HlyA＋InvA＋ipaH，引物Ⅱ为Cadc＋Oprl＋Ent＋23SrRNA。效果良好。实验确定了适宜的PCR反应循环数为35个循环，适宜的杂交温度为48℃。用实验制备的基因芯片对模拟水样检测结果的准确率达100％，说明该基因芯片对目的细菌特征基因的检测结果是可靠的。用该方法对食品企业污水水样进行检测具有高准确率，为今后更大规模的检测研究奠定了基础。     

Decomposition of CCl4 and CHCl3 on gliding arc plasma

Introduction C hlorinated volatile organic com pounds(C V O C s) w ere released to the atm osphere as flue gases from various industrial processes. C hlorinated hydrocar- bons have been w idely accepted as solvents and chem ical interm ediates in the m an…     

Treatment of pharmaceutical wastewater containing recalcitrant compounds in a Fenton-coagulation process

The advanced treatment using integrated Fenton＇s reaction and coagulation process was investigated in this study. Before the advancement, the pharmaceutical wastewater containing lincomycin hydrochloride was pretreated by UASB （upflow anaerobic sludge bed） and a SBR （sequencing batch reactor） process. The residual recalcitrant compounds, measured by gas chromatographymass spectrometry （GC-MS）, mainly consisted of alcohols, phenols, and nitrogenous and sulfur compounds. The experimental results indicated that when the Fenton＇s reaction was conducted at pH=3.0, H2O2CODOcr=0.27, H2O2/Fe^2＋=3：1 and 30 min of reaction time, and the coagulation process operated at a sulfate aluminum concentration of 800 mg/L and pH value of 5.0, the color and COD in the wastewater decreased by 94% and 73%, respectively; with a finale COD concentration of 267 mg/L and color level of 40 units, meeting the secondary standard of GB8978-1996 for industrial wastewater.     

Photo-degradation of Acid-red 3B dye catalyzed by TiO2 nanotubes

Introduction A s one kind of novel functional m aterial, TiO 2 nanotube has been found potential applications in solar cell (B arbe et al., 1997), sem iconductor device (V inodgopal et al., 1993) and catalyst supports (Idakiev et al., 2005) etc. Since K a…