PAC与膨润土强化SBR工艺处理含氨氮河水研究

研究了室温条件下粉末活性炭(PAC)和天然膨润土静态吸附氨氮的能力;通过对氨氮、TN和污泥硝化活性指标的分析,对比分别考察了PAC和膨润土强化间歇式活性污泥法(SBR)强化系统的脱氮效果.结果表明,PAC和膨润土对氨氮均具有一定的吸附作用,后者的吸附效果明显好于前者;与传统SBR工艺相比,SBR反应器中投加PAC和膨润土后,氨氮去除率分别提高12%和8%,脱氮率分别提高30%和24%;PAC和膨润土可以促进硝化菌和反硝化菌的增殖,增强硝化和反硝化功能,从而提高系统的脱氮效果.     

反硝化细菌固定化降解亚硝酸盐的研究

研究了以海藻酸钠(SA)、聚乙烯醇(PVA)、聚乙烯醇和海藻酸钠的混合物(PVA+SA)为包埋材料固定化反硝化细菌降解亚硝酸盐的影响,并详细考察了PVA+SA固定化反硝化菌降解亚硝酸盐的影响因素。结果表明,以PVA+SA为包埋材料制备的反硝化细菌小球与SA和PVA相比具有明显优势。较优化的条件为:PVA和SA比例10∶1,温度28℃,以葡萄糖为碳源,碳氮比2.5∶1。在较优化条件下,亚硝酸盐氮的最大去除率在72 h内能达到92%。     

反硝化细菌固定化降解亚硝酸盐的研究

研究了以海藻酸钠(SA)、聚乙烯醇(PVA)、聚乙烯醇和海藻酸钠的混合物(PVA+SA)为包埋材料固定化反硝化细菌降解亚硝酸盐的影响,并详细考察了PVA+SA固定化反硝化菌降解亚硝酸盐的影响因素。结果表明,以PVA+SA为包埋材料制备的反硝化细菌小球与SA和PVA相比具有明显优势。较优化的条件为:PVA和SA比例10∶1,温度28℃,以葡萄糖为碳源,碳氮比2.5∶1。在较优化条件下,亚硝酸盐氮的最大去除率在72 h内能达到92%。     

复合固定硝化细菌降解小型景观水体中的氨氮

以壳聚糖和聚乙烯醇(PVA)共混材料为基质,添加少量二氧化硅,包埋硝化菌制备固定化小球并通过正交实验探索得出其优化制备条件;探究了固定化硝化菌小球对模拟景观水中氨氮降解效果的影响,并对比游离菌的降解效果。结果表明,固定化硝化菌处理NH_4~+-N的质量浓度10 mg/L的模拟景观水中12 h,降解率在初次及重复使用1次的情况下均可达到94%以上。固定化菌株对温度、pH变化有着优良的耐受性且明显优于游离菌,其优化的固定化硝化菌小球质量与模拟景观水体积比为2 mg/100 mL,在温度30℃、pH为7、COD/ρ(TN)为2的条件下处理效果最好。测得其反应动力学符合Monod方程,其最大比降解速率为2.965μg/(L·s),饱和常数为60.49 mg/L。     

固定化硝化细菌去除氨氮特性的研究

不同比例因素制备的固定化硝化细菌小球去除氨氮的效率差别很大。文章使用正交试验,通过直观分析和模型分析找出固定化小球去除氨氮的最佳因素水平值。确定了在PVA质量浓度为10%,活性炭含量占PVA凝胶的2%,交联时间32 h及包菌量的值为1︰2的情况下,包埋的固定化小球去除氨氮的效率最高,42 h就可以达到80%以上,去除氨氮效率强。     

海洋石油降解菌固定化小球的制备及其对含油海水的降解特性

以实验室前期筛选分离得到的海洋石油降解菌SI-JHS为供试菌,在不同包埋条件下对SI-JHS进行固定化以提高其对含油海水的降解率,考察了pH值、盐度和温度等海水环境条件对固定化小球降解特性的影响。实验结果表明,包埋剂选用10%（质量分数,下同）的聚乙烯醇（PVA）和1%的海藻酸钠（SA）混合液,交联剂选用含3% CaCl₂的硼酸饱和溶液,包菌量为20%,活性炭添加量为5%时制备出的固定化小球成球性好,具有较好的传质性能和机械强度。SI-JHS固定化小球对含油海水的最适宜降解条件为：pH值7.0~7.5、盐度3%~4%、温度30~35℃。SI-JHS固定化小球对含油海水的降解率为97.8%,较游离菌提高了22.6%,固定化小球对海水中石油的降解过程符合准一级降解动力学模型。     

固体碳源联合反硝化菌脱氮的影响因素研究

采用聚乙烯醇(PVA)、海藻酸钠、谷壳、反硝化细菌等利用包埋固定化技术制备成3种不同成分的固定化反硝化细菌联合固体碳源的小球,分别在不同的条件下研究外加碳源和固定化反硝化菌对脱氮效果的影响。结果表明,在有外加碳源时,固体碳源小球能提高污水中的C/N,在相同的条件下,投加和未加含有固体碳源的小球对NO_3~--N的去除率分别达到95.22%和57.89%;在小球中固定化微生物时,其去除性能更好,在相同的条件下,固定和未固定微生物的小球对NO_3~--N的去除率分别为95.22%和87.11%。2种情形下的优化温度和p H分别为30℃和7.5。     

固定化活性污泥法处理氨氮废水的研究

研究了以聚乙烯醇（PVA）为骨架载体,添加适量的添加剂,利用活性炭吸附硝化细菌,采用包埋法制作固定化硝化小球,去除水中氨氮的方法。通过实验寻找出最优的实验条件,氨氮去除率最大可达到97.8%。该方法去除水中氨氮,具有效率高、稳定性强、生物浓度高、能保持高效菌种的优点,故在水处理领域有广泛的应用前景。     

生物活性炭纤维小球对养殖池塘处理及除氮优势菌的鉴定研究

采用生物活性炭纤维小球处理养殖池塘水体中氨氮,研究了不同浓度的氨氮去除情况。结果表明:在1～7 d,5、25、50 mg/L的氨氮去除效果均呈上升趋势,最佳去除率分别达到了85.4%、79.5%、76.7%;在8～14 d,对氨氮的去除效果均处于一个波动过程,但在14 d内,去除率分别保持在74%、65%、63%以上;在15～21 d对氨氮的去除效果均呈下降趋势。生物活性炭纤维小球在处理氨氮过程中亚硝酸盐氮和硝酸盐氮也是处于变化的动态过程。通过多次反复筛选,从生物活性炭纤维小球中筛选出对氨氮具有较强去除效能的优势菌。通过对菌株的个体形态特征、菌落形态特征进行观察,最终确定2种优势菌为硝化菌和恶臭假单胞菌。对2种优势菌的生态影响因子研究表明,最适宜的温度为25～35℃,适宜的pH为中性及偏碱性。在相同的环境条件下,硝化菌对氨氮的去除效果优于恶臭假单胞菌。     

温度/pH双响应硝化菌凝胶球的制备及特性研究

采用包埋法制备了粒径均匀的海藻酸钙(CA)硝化菌小球,并用不同浓度的NaCl溶液处理CA硝化菌小球来改善其扩散传质性能,以N-异丙基丙烯酰胺(NIPAAm)、丙烯酸(AA)为单体材料,形成温度/pH响应层,制得一种新型温度/pH双响应硝化菌凝胶小球。以NH4+?N为指示物考察不同制备条件下硝化菌凝胶小球的氨氮去除性能及对温度、pH的敏感特性,并将其应用于实际废水的脱氮处理。结果表明,经浓度为0.3%的NaCl溶液改性后的CA硝化菌小球的扩散传质性能最佳;15 mL温度响应溶液中NIPAAm为200 mg、MBA为4 mg,10 mL pH响应溶液中AA为200 mg、MBA为4 mg时双响应硝化菌小球的氨氮去除性能最好;当温度低至4℃时,氨氮去除率可达29.45%,当pH为9时,氨氮去除率仍可达35.48%。双响应硝化菌凝胶小球具有良好的温度、pH敏感特性,对实际废水中氨氮的去除也具有良好效果,有利于提高低温及碱性条件下硝化菌的硝化效果。     

氢气纯度分析方法准确性的探讨

ONACCURACYOFANALYSISOFOFHYDROGEN1前言我公司目前应用的氢气纯度分析方法有两种,一种是爆炸反应法,另一种是焦性没食子酸吸收法。几年来,人们对两种分析方法的准确性曾有过褒贬不一的评论。这里我们也谈谈自己粗浅的观点。2爆炸法测定氢气纯度一定量的氢气样品与适量的空气之均匀混合物因反应后生成液体水而引起气体体积减少,减少的体积等于参加反应气体体积之和。其中l／3为氧气,2／3为氢气。根据氢气取样量和反应前后混气体体积之差,以及氢气在反应中的体积比例关系,可计算出样品的氢气纯度。计算公式式中：A一混…     

COMPARISON OF METHODS OF ANALYSIS OF GYPSUM1

The different analytical methods proposed for the evaluation of gypsum have been subjected to an experimental test. A combination method, consisting of a fusion with KHCO₃ and determination of CaO by KMnO₄ titration, the SO₃ by Andrews method of titration of BaCrO₄ has been found to give very reliable results with the least consumption of time.     

SEDIMENTATION OF BINARY MIXTURES OF PARTICLES OF UNEQUAL DENSITIES AND OF DIFFERENT SIZES

A model is developed for the sedimentation from a suspension of two particle species of unequal densities and of different sizes. The composition and the thickness of various layers in the sediments are predicted using graphical and analytical methods. The model predictions were in excellent agreement with experimental results, when the particle size ratio was ≥ 108. When size ratio of the particles was 2.60 and 4.31 the agreement occurred in about 50 percent of the cases.     

HEASUREHENT OF INSTANTANEOUS RATES OF LOSS OF VOIATILE COMPOUNDS DURING DRYING OF DROPS

A novel technique serves to monitor instantaneous rates of loss of a volatile solute from a suspended drop during drying. A highly sensitive electron capture detector is used to monitor concentrations of SF6 released into a flowing gas stream from a suspended, drying drop. Simultaneously, the appearance and morphological development of the drop are monitored with a video camera. This provides the wherewithal of relating instantaneous rates of loss of the volatile solute to particular events during the development of particle morphology.

Initial experiments have been carried out with drops of aqueous solutions of glucose, sucrose, maltodextrin and coffee extract. The results clearly display the onset of the volatiles-retentive selective diffusion phenomenon. There is also substantial loss of the volatile component later in the drying process, when the drops undergo repeated ex ansion, bursting and cratering due to the formation of internaf bubbles. These experiments appear to be the first quantitative demonstration of major losses accompanying changes in drop morphology.     

茶多酚提取方法进展

本文综述了国内外现有茶多酚提取方法的现状以及近期的研究进展，并对其优缺点进行了评价。这将有助于中低档茶的综合利用和茶多酚的进一步开发应用。     

ANALYSIS OF RECENT MEASUREMENTS OF THE VISCOSITY OF GLASSES

Viscosity of Simple Soda-Silicate 500° to 1400°C Comparison of the results given by English with those of Washburn, Shelton and Libman, indicates a discrepancy in the absolute values of log₁₀ viscosity amounting to 0.6, those of Washburn et al., being relatively too high. If correction for this is made, the isothermal curves of log₁₀ viscosity as a function of soda content are smooth up to 50% Na₂O, showing no inflection. The observations as a function of temperature T are all represented within accidental error by an equation of the type where all three constants vary regularly with the composition. Change of Viscosity of Glass (6SiO₂, 2Na₂O) due to Molecular Substitution of CaO, MgO and Al₂O₃ for Na₂O The effect is clearly brought out by plotting (from the results of English) the change of log₁₀η due to the substitution as a function of temperature. The curves each show a sharp bend at a temperature between 840° and 1050°C, which is designated the aggregation temperature T_a. If we divide these curves by the corresponding percentage substituted, we get curves for each oxide which are straight and parallel below the aggregation temperatures, the slopes (increase of change of log₁₀η per 100°C) being −0.056 (CaO), −0.055 (MgO), −0.018 (A1₂O₃) per per cent oxide substituted. For substitution of 1/2 molecule the slopes are −0.325 (CaO), −0.23 (MgO) and −0.18 (Al₂O₃) per 100°. At the aggregation temperature the change of log₁₀η per per cent is a minimum, 0.03 to 0.06 for CaO, 0.12 for MgO, 0.07 for Al₂O₃. Evidence of Aggregation in Glasses, from viscosity Measurements The sharp bends in the plots of change of log₁₀η due to substitution of an oxide for Na₂O, suggest the beginning of molecular aggregation at these temperatures. These aggregation temperatures are close to the devitrification temperatures, but the effect on the viscosity curves cannot be due to actual devitrification since it does not change with time. Taking the aggregation temperatures as equal to devitrification temperatures, additional isotherms are roughly sketched into the equilibrium triangle of the system Na₂O-CaO-SiO₂. Change of Viscosity of Glass (4SiO₂, 2Na₂O) due to of Substitution of B₂O₃ for SiO₂ The change of log₁₀η (from the results of English) is plotted as a function of temperature, and also the change of log₁₀η per per cent B₂O₃. The curves are more complex than for the substitution for Na₂O.     

环氧树脂羟基值测定方法的研究

利用乙酸酐、吡啶和浓硫酸混合的乙酰化试剂测定环氧树脂中羟基值含量的方法具有操作简便、滴定终点明显和分析结果误差小等优点。     

骑式摩托车油箱喷涂工艺的改进

面对日益激烈的市场竞争,摩托车油箱外观质量越来越成为影响销售的因素之一。文章介绍了改进工艺后的油箱涂装,该涂装体系提高了油箱外观的丰满度,降低了油箱涂装的生产成本。     

几种针状焦性能对比

针状焦分石油系和煤系两大类,这主要取决于针状焦的原料来源。在同一系列中由于原料不同和工艺条件不同 ,针状焦的各自性能也不相同。针状焦是生产超高功率石墨电极和高功率石墨电极的主要原料 ,针状焦的性能对石墨电极的质量有至关重要的影响。所以对针状焦性能以及其对石墨电极质量影响的研究十分必要的。以下是常用的几种进口针状焦和国产针状焦的性能对比。１原料性能分析对比原料试样包括４种针状焦 ,其中两种为进口针状焦：三菱针状焦和新日化针状焦;另两种为国产针状焦：鞍山针状焦和锦州针状焦。其中除锦州针状焦是石油系针状焦外…     

聚酰亚胺的合成法

本文评述了缩聚型聚酰亚胺的主要合成方法和近年来国际上在合成中所做的探索。