某烷基苯厂F-101A加热炉炉管爆炸事故分析

本文针对某烷基苯厂F-101A加热炉炉管爆炸事故原因进行了深入分析,根据该起爆炸事故的伤亡情况、事故经济损失、事故现场建(构)筑物损害情况,应用蒸气云爆炸模型对该爆炸事故后果严重度进行了计算分析,计算结果与爆炸现场基本吻合,能比较客观地反映爆炸事故实际情况,可为该类事故原因分析提供借鉴.     

草酸促进双酚A在黏土矿物悬浮液中光降解研究

选择两种常见的天然黏土矿物高岭石和蒙脱石,研究了有机污染物双酚A(BPA)在其表面的吸附及草酸对黏土矿物悬浮液中BPA光降解的影响.结果表明,BPA在两种黏土矿物表面的吸附量较小,吸附符合Langmuir等温式.在250W金属卤化物灯(λ≥360nm)照射下,草酸可显著促进BPA在高岭石和蒙脱石悬浮液中的光降解,降解动力学符合Langmuir-Hinshelwood方程. 降解速率受pH值的影响较大,pH=4.0时速度最快,光降解速率同时受草酸浓度的影响.最后,通过分析矿物中铁的化学环境及反应过程中铁浓度变化,分析了草酸促进BPA在黏土矿物悬浮液中光降解的可能机制.     

Effects of nonionic surfactant Triton X-100 on the laccase-catalyzed conversion of bisphenol A

The laccase-catalyzed conversion of bisphenol A (BPA) in aqueous solutions was studied in the absence and presence of nonionic surfactant Triton X-100. It was found that the addition of Triton X-100 into the reaction system increased the conversion of BPA, especially near the critical micelle concentration of Triton X-100. Also it was found that the stability of laccase was greatly improved in the presence of TritonX-100. Studies on the endogenous fluorescence emission of laccase indicated that there existed an interaction between Triton X-100 and laccase, which was beneficial to folding and stabilizating of laccase. The binding of Triton X-100 to the laccase surface also mitigated the inactivation e ect caused by the free radicals and polymerization products. Under otherwise identical conditions, a lower dosage of laccase was needed for the higher conversion of BPA in the presence of Triton X-100.     

山东省广饶县污水处理厂工艺对比研究

介绍了广饶县污水处理厂一期、二期工艺即淹没式生物膜工艺和改良式A2/O工艺的特点及运行情况,分析了每个阶段对污染物的去除原理,并进行对比。结果表明:1)两个工艺对有机物的去除效果相当;2)改良式A2/O工艺对TN的去除效果优于淹没式生物膜工艺,主要是因为改良式A2/O工艺增加了内回流,增强了反硝化效果;3)两个工艺对TP的去除效果相当。     

西安市高新区第二污水处理厂工艺设计总结分析

西安高新区第二污水厂近期和远期设计规模分别为5×104m3/d和10×104m3/d,采用A2/O-混合反应沉淀-砂滤组合工艺,出水执行标准《城镇污水处理厂污染物排放标准》(GB 18918-2002)的一级A标准,同时采用活性氧进行除臭。工程设计中充分考虑来水量的变化,在各处理单元进行合理选择,为相关工程提供了借鉴和参考。     

Furfural residues from straw become complex fertilizer by addition method

ＩｎｔｒｏｄｕｃｔｉｏｎＦｕｒｆｕｒａｌｉｓａｋｉｎｄｏｆｉｍｐｏｒｔａｎｔｒａｗｍａｔｅｒｉａｌｉｎｃｈｅｍｉｃａｌｉｎｄｕｓｔｒｙ.Ｗｉｔｈｔｈｅｇｒｏｗｔｈｏｆｉｔｓｕｓｅ,ｉｔｓｐｒｏｄｕｃｔｉｏｎｉｓｉｎｃｒｅａｓｉｎｇａｎｎｕａｌｌｙ.Ｂｕ?..     

Maternal serum human chorionic gonadotrophin and pregnancy-associated plasma protein a,markers for fetal down syndrome at 8–14 weeks

Maternal serum levels of human chorionic gonadotrophin and its subunits (intact, α, and free βhCG) and pregnancy-associated plasma protein A (PAPP-A) were measured in 279 women between 8 and 14 weeks' gestation. This group included 23 pregnancies in which the fetus had Down syndrome (DS), diagnosed either at birth or during the second trimester (n=17) or from chorionic villus sampling (CVS) (n=6). Normal medians were determined from the 258 apparently normal pregnancies. The median levels of intact hCG (1·4 MOM) and free βhCG (2·1 MOM) were significantly raised, whereas the median level of PAPP-A (0·39 MOM) was significantly lower in the DS pregnancies when compared with the control group. Levels of αhCG were similar in both the control and the DS pregnancies. Analysis of samples taken prior to 14 weeks' gestation demonstrated that only PAPP-A (0·34 MOM) was significantly altered in DS pregnancies. However, after the exclusion of DS cases diagnosed at CVS, the median intact hCG (1·56 MOM), free βhCG (2·27 MOM), and αhCG (1·8 MOM) were all raised in DS pregnancies. This emphasizes the problem of the interpretation of biochemical markers when DS cases are diagnosed at CVS.     

生物膜法A/O系统处理腈纶废水工业试验

本工业试验规模为１４００—１６００ｔ／ｄ,装置Ａ／Ｏ容积比１：３,当平均停留时间２２．６ｈ,回流比３．２,水温约３５℃左右时,平均去除率ＣＯＤｃｒ达８８．３６％、ＢＯＤ５９７．４９％、ＴＮ７７．６７％、ＡＮ９９．４１％。出水各项指标平均值为ＣＯＤＣｒ５３．５７ｍｇ／Ｌ、ＢＯＤ５５．６ｍｇ／Ｌ、ＴＮ１４．９４ｍｇ／Ｌ、ＮＨ３－Ｎ６．９２ｍｇ／Ｌ、ＡＮ１．０２ｍｇ／Ｌ、ＮａＳＣＮ２．６７ｍｇ／Ｌ,ＳＳ仅２０ｍｇ／Ｌ,因此不设二沉池。     

Simultaneous removal of arsenate and fluoride from water by AI-Fe （hydr）oxides

A1-Fe （hydr）oxides with different A1/Fe molar ratios （4：1, 1：1, 1：4, 0：1） were prepared using a co- precipitation method and were then employed for simultaneous removal of arsenate and fluoride. The 4A1 ： Fe was superior to other adsorbents for removal of arsenate and fluoride in the pH range of 5.0-9.0. The adsorption capacity of the A1-Fe （hydr）oxides for arsenate and fluoride at pH 6.50.3 increased with increasing A1 content in the adsorbents. The linear relationship between the amount of OH released from the adsorbent and the amount of arsenate or fluoride adsorbent by 4A1 ： Fe indicated that the adsorption of arsenate and fluoride by A1- Fe （hydr）oxides was realized primarily through quantita- tive ligand exchange. Moreover, there was a very good correlation between the surface hydroxyl group densities of A1-Fe （hydr）oxides and their adsorption capacities for arsenate or fluoride. The highest adsorption capacity for arsenate and fluoride by 4A1 ： Fe is mainly ascribed to its highest surface hydroxyl group density besides its largest pHpzc. The dosage of adsorbent necessary to remove arsenate and fluoride to meet the drinking water standard was mainly determined by the presence of fluoride since fluoride was generally present in groundwater at much higher concentration than arsenate.