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1.
焦化厂废水最大的特点是在废水中含有通称为固定铵和挥发氨的强、弱酸的铵盐,其含量折算成氮为250-750mg/L。废水中除了含有铵盐外,还含有多种其它的氮化合物,这些氮的化合物生物破坏过程伴随着铵盐进一步生成,这就是硫氰化物和氰化物,以及有机化合物──毗啶、喹琳及其衍生物等,这些化合物转化过程的反应式如下:NaCNS+2H2O+2O2→NaNH4SO4+CO2(1)2C5H5N+11O2+2H2O→8CO2+2H2O+2NH4HCO3(2)4NaCN+O2+10H2O→4NaNH4HCO3(3)(…  相似文献   

2.
比较不同NaCl、Ca2+、PO3-4等离子浓度对嗜盐隐杆藻(Aphanothecehalophytica)细胞生长及胞外多糖(Exopolysac-charideEPS)产量的影响。在各影响因子不同浓度的培养条件下,0.5mol/L的NaCl、1.0g/L的Ca(NO3)2·4H2O、0.1g/L的KH2PO4分别是其最佳生长浓度。EPS的产量在0.5mol/LNaCl、,0.5g/LCa(NO3)2·4H2O、0.5g/L的KH2PO4培养条件下最高。在较低的Ca2+、Mg2+、PO3-4浓度下可提高EPS产率。  相似文献   

3.
含SiC最高达11%的Ni-SiC复合镀层的镀液配方及操作条件为:Ni(SO_3.NH_2)_2·4H_2O410,NiCl_2·6H_2O10,H_3BO_350,OP-100.4及SiC(3μm)20-120g/L,pH4,55±2℃,5A/dm ̄2,需搅拌.  相似文献   

4.
在V—Sb—O催化剂上丙烷氨氧化反应动力学研究   总被引:2,自引:3,他引:2  
在自制的V-Sb/Al催化剂(VSb5WP0.5Sn0.5Ox)上,系统地考察了原料气中氨比(NH3/C3H8)为1~2.5、氧比(O2/C3H8)为2~4和水比(H2O(g)/C3H8)为0~5对丙烷氨氧化制丙烯腈反应结果的影响;根据实验数据确定了该反应体系的网络模型,并用氧化-还原机理建立了丙烷氨氧化反应制丙烯腈的反应动力学模型。  相似文献   

5.
运用TG、DTA,研究了VO(H2PO4)2在流动空气气氛中的热反应行为、非等温反应动力学和热效应。VO(H2PO4)2从609K开始失重,到695K失重完毕,失重率为14.01%,失重后的产物为VO(PO3)2。运用Sharp法、Coats-Redfern法和Doyle-Zsako法对基础实验数据进行分析,推断出该热分解反应机理为成核和生长(n=1),动力学函数为Avrami-Erofeev方程;非等温热分解反应动力学方程:dα/dT=A/βe-E/RT(1-α);动力学补偿方程:lnA=0.181E-4.68b;热分解反应转变热为0.291kJ·g-1。  相似文献   

6.
浸渍活性炭脱除H2S的反应动力学   总被引:6,自引:0,他引:6  
提出了浸渍活性炭脱除H2S的反应过程机理模型,认为脱硫过程主要是H2S在活性炭的吸附水膜内离解后被活化的O2分子以及活性氧原子氧化生成单质硫逐渐沉积在活性炭表面,同时应用最小二乘法回归实验数据得到了脱硫动力学方程dWs/dt=k1k2/apo2/pH2S/1+k2po2×(1-αWs)^2其中动力学参数k1=3.753×10^5exp「-3006.5/Tr」k2/0.263exp「1945.6/T  相似文献   

7.
在隔离式电解槽中,用泡沫铅(SPb)作阴极,铂(Pt)作阳极,饮和甘汞电极(SCE)作参考电极,以CH3CN+C2H5OH+H2O_Bu4NBr为电解体系,对由煤沥青为原料制得的中国相沥青(MP)进行电解加氢研究,当c(CH3CN):c(C2HOH):c(H2O)=0.4:0.1:1(浓度比),c(Bu4NB4)=0.31mol/L,t=30C,p(MP)=50g/L,阴极电解电位为-2.4V时,  相似文献   

8.
近几年开发的国外农药新品种(6)   总被引:3,自引:0,他引:3  
刘长令 《农药》1999,38(8):42-44
玉嘧磺隆(rimsulfuron)NSO2C2H5SO2NHCNHONNOCH3OCH3C14H17N5O7S24314中文通用名称玉嘧磺隆英文通用名称rimsulfuron(BSI,ISO,ANSI)商品名称Titus(宝成)其它名称DPX-E9...  相似文献   

9.
讨论了镀液组成对镀层成份、结构和表面形貌的影响.结果表明,镀层中的W,P和SiC含量随着Na2WO4·2H2O浓度的提高而增加,随着H3C6H5O7·H2O浓度的升高而降低;Na2WO4·2H2O和H3C6H5O7·H2O浓度对复合镀层的结构影响不大,但对镀层表面形貌影响较大,当Na2WO4·2H2O的浓度为90~150g/L,H3C6H5O7·H2O的浓度为150~170g/L时,可得到颗粒较细的镀层.  相似文献   

10.
缔合法磷酸二铵氨化反应特征的研究   总被引:1,自引:0,他引:1  
研究了氨和磷酸缔合物生成磷酸一铵的化学反应特征。其反应式为:(R3NH)H2PO4+NH3→R3N+(NH4)H2PO4获得了两个温度范围的反应速率方程:20~50℃:-γA=8.678×103·exp(-1.9564×103·1/T·C0.3A50~80℃:-γA=0.4203×102·exp(-0.9780×103·1/T·C0.3A方程计算与实测在相同与不同温度时的平均误差分别为-4.29%和-0.32%。研究结论:反应级数n=0.3;反应为受液膜控制的快速反应;生成磷酸二铵的反应有一慢速区,反应分为两段进行较为经济。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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…  相似文献   

14.
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。  相似文献   

15.
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.  相似文献   

16.
用两个形状指数表征粉煤灰颗粒形貌的研究   总被引:5,自引:0,他引:5  
陆厚根  马魁 《硅酸盐学报》1992,20(4):293-301
引用两个形状指数表征颗粒形状的概念,即先将颗粒形状近似为椭圆,再将椭圆图像分离:以圆为基准的颗粒宏观形状指数δ;以光滑椭圆为基准的颗粒轮廓凹凸度,即微观形状指数ζ。分析和发展了近似椭圆模型。并运用图像分析仪对粉煤灰、水泥样品进行实验。结果表明,粉煤灰颗粒的两个形状指数δ和ζ都大于水泥颗粒。证明粉煤灰颗粒的球形度、表面光滑度优于水泥,而且,随着粒径增大,δ和ζ呈下降趋势,表明磨制颗粒越粗。(?)粒形状越不规则。文中还运用近似椭圆模型再现了颗粒的模拟图像。  相似文献   

17.
顾Fan 《煤炭转化》1993,16(4):62-67
本文以三种典型煤的碳燃烧为研究对象,分别采用简单一维沉降燃烧方式和等温加热燃烧方式,实验研究了煤在快速加热条件下,其碳的初期和中,后期燃烧过程。以实验为基础,建立了煤的碳燃烧模型,变工况数值模拟了煤的碳燃烧过程,揭示了煤不同条件下的单颗粒碳燃烧特性。  相似文献   

18.
茶多酚提取方法进展   总被引:22,自引:0,他引:22  
葛宜掌  金红 《精细化工》1994,11(4):52-55
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。  相似文献   

19.
归纳了当今卫生陶瓷工业的发展现状和水平 ,对窑炉产业提出了的新要求 ,分析了某一新型窑炉的特点 ,对发展我国陶瓷窑炉产业提出了建议  相似文献   

20.
ANALYSIS OF RECENT MEASUREMENTS OF THE VISCOSITY OF GLASSES   总被引:5,自引:0,他引:5  
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 Ta. 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.  相似文献   

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