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1.
酶技术在栽培食用菌废弃物二次利用中的研究   总被引:2,自引:0,他引:2  
本研究运用酶工程技术,采用以纤维酶为主的多酶系统强化降解经一方法预处理后的栽培食用菌废弃物(简称菌渣),以提高其作为饲料原料的营养水平和对畜禽的适口性,结果表明,采用预处理-酶解工艺可使菌渣中粗纤维含量从28.13%降低到16.23%~21.20%,可溶性精蛋白可从1.11%提高到3.4%~4.58%,可溶性还原糖从0.91%提高到1.27%~4.38%。蛋白氨基酸提高1.15%,总游离氨基酸提高  相似文献   

2.
采用凝聚沉淀法对某厂云母纸生产废水进行处理研究,实验结果表明,在PH=6,浓度为4.5%的明矾溶液投加1%,浓度为1‰的PAM投加0.5‰时,能有效地降低废水中的乳浮物含量,且污泥含水率低。  相似文献   

3.
酸性分散染料废水的治理及综合利用研究   总被引:4,自引:0,他引:4  
利用硫酸含量达15%-40%的酸性分散染料废水和废铁作用制得聚合硫酸铁,并用其作净水剂处理印染废水。结果表明,每t酸性废水可生产1.05t浓度160g/LFe^3+的取合硫酸铁溶液,出水的酸含量降低了83.5%。用所制得的聚合硫酸铁处理印染废水,COD去除率可达70.4%-95.4%,色度去除率可达65.7%_90.5%,具有较好处理效果。  相似文献   

4.
应用大型空气质量实验舱平台,分别测试盘式固体蚊香、片型电蚊香和液体电蚊香的PM2.5和主要气态污染物散发量。采用定释放浓度法,获得PM2.5和主要气态污染物排放因子。结果显示,盘式固体蚊香、液体电蚊香、片型电蚊香的PM2.5排放因子分别为12.9、1.3、2.6mg/h,总挥发性有机物(TVOC)排放因子分别为103.4、69.5、58.8mg/h,甲醛排放因子分别为16.0、8.9、12.5mg/h,3种蚊香排放的主要苯系污染物排放水平相当,此外盘式固体蚊香还散发CO,排放因子为925.4mg/h。对盘式固体蚊香散发颗粒物的数浓度谱分布进行了拟合分析,发现数浓度谱分布具有良好的自模性,拟合得出计数中位径(CMD)为90nm,几何标准差(GSD)为1.65;假设蚊香释放颗粒物为密度1.4g/cm3的球形颗粒,利用质量浓度和数浓度谱分布特征反算得出各类蚊香散发颗粒物的数浓度排放因子。通过案例计算,发现房间在正常通风条件(换气次数为2.0次/h)下使用各类蚊香时散发的TVOC浓度将超标1.8~3.2倍,甲醛超标1.5~3.0倍;盘式固体蚊香散发的PM2.5超标近1.5倍,CO超标1.7倍。对封闭环境下,通风条件很差(换气次数为0.5次/h),此时所有污染物浓度将增大4倍,污染更加严重。  相似文献   

5.
采用炼钢烟灰制取高纯度硫酸锌,研究了制取条件对收率和产品质量的影响,试验结果表明,控制适宜的酸浸条件,锌浸取率≥98%,铁浸取率可控制在0.02%以下,当酸浸工艺条件液固比为3:1,温度80-90℃,硫酸加入量39g/L(酸浸液)滴酸时间1.5h浸取时间2h,再用空气和过氧化氢氧化除去溶液中的铁,产品中硫酸锌含量≥99%,铁含量可降至0.5mg/L以下。  相似文献   

6.
凹凸棒土颗粒吸附剂的制备   总被引:12,自引:0,他引:12  
讨论了凹凸棒土的复配造粒及再生方法,考察了造粒添加剂的种类,焙烧温度,焙烧时间等因素对颗粒强度和脱色性能的影响。研究结果表明:凹凸棒土颗粒吸附剂制备的工艺条件是,凹凸棒土:AlCl3:MgCl2.6H2O:MsSO4.7H2O=1:05%:1%:1%,焙烧温度为450℃,焙烧时间为1h,吸附饱和后的颗粒吸附剂可以采用热再生。  相似文献   

7.
本文采用标准方法,测定了白洋淀北岸部分农田土壤的粒度组成、pH和有机碳含量等指标,对该地区土壤的特性进行了表征分析。结果表明,土壤的平均粒度分布大于20μm的占52.73%,主要属于砂壤土。与10年前相比,pH值变化不大;而有机碳含量是10年前的1.26倍。pH随土壤的垂直深度而略有增加,而有机碳含量则随土壤的垂直深度而减少。  相似文献   

8.
研究了用双硫腙-醋酸丁酯萃取火焰原子吸收法测定海水中微量锌的最佳条件。实验表明,在pH7 ̄8时能定量萃取锌。方法的相对标准偏差为3.1%,加标回收率为93% ̄100%,检出限为0.84μg/L。  相似文献   

9.
兼氧接触工艺处理造纸中段废水中间试验的研究   总被引:1,自引:0,他引:1  
采用中试规律的兼氧接触工艺处理造纸中段废水,当处理水量为4.8m^3/d,水力停留时间3~4h,气水比3:1,进水PH8~9.5,平均COD浓度为1641.6mg/l,BOD5516.1mg/l,SS688.4mg/l的条件下,处理后出水pH7.5左右,平均COD浓度为1059.8mg/l,去除率34.9%,BOD5246.5mg/l,去除率52.1%,SS161.9mg/l,去除率为77.1%。  相似文献   

10.
液相色谱测定土壤中氟磺胺草醚残留量方法研究   总被引:4,自引:0,他引:4  
采用甲醇/浓盐酸浸渍振荡提取,二氯甲烷萃取,经弗罗里硅土柱层析净化,用液相色谱法测定。方法的最低检出含量为0.02mg/kg,添加回收率在95.8% ̄96.6%之间。  相似文献   

11.
A method was developed to determine trace concentrations of a range of individual PCB congeners in biological samples (serum, food and faeces) using GC-MS, to prepare a mass balance of PCBs in humans. A simple method for the analysis of PCBs in human serum, which excluded an extraction step, was first employed. Results indicated that the recoveries of 13C12 PCB spikes were variable. A soxhlet extraction step was added and was found to be efficient and reproducible. A quality control routine and method validation results are presented. In batch tests of the methods presented it was found that the serum analysis method gave within batch mean 13C12 spike recoveries of 98-120% and standard deviations between 6 and 20%. The food/faeces analysis method gave within-batch mean 13C12 spike recoveries of 88-100%, and within batch standard deviations between 4 and 12%. The batch to batch mean recovery for serum analysis was 100%, with an RSD of 9% for high spikes and 10% for low spikes. For food/faeces analysis the batch to batch average recovery was 110%, with an RSD of 5% for high spikes and 9% for low spikes.  相似文献   

12.
利用微生物膜法快速测定水中的BOD,用质控样和标液进行方法准确度和精密度的考察,标准偏差在0.9%~5.2%之间,相对误差≤4.0%,加标回收率为95.5%~103%.与接种稀释法进行对比实验,相对误差在1.5%~10.3%范围内,两种方法测定结果基本一致.  相似文献   

13.
方淑琴 《污染防治技术》2010,23(2):77-78,81
对异烟酸-吡唑啉酮光度法测定水和废水中氰化物的方法进行了改进。在不改变其它步骤的前提下,以去离子水代替二甲基甲酰胺所配制的吡唑啉酮溶液及异烟酸溶液作为显色剂。试验结果表明,改进后的新方法精密度RSD〈5%,加标回收率为92.0%~105.0%,通过电镀废水和标准样品的比对试验表明,改进后的方法与标准方法对同一样品的测定结果无显著性差异,满足监测分析要求。  相似文献   

14.
An analytical method was developed for determining organophosphate pesticides (OPP) and pyrethroid pesticides (PYR) in duplicate-diet solid food. The method consisted of pressurized liquid extraction (PLE) with dichloromethane followed by cleanup with gel permeation and solid phase extraction columns and gas chromatography/mass spectrometry (GC/MS) analysis. Quantitative recoveries (73-117 %) of the target pesticides were obtained for spiked duplicate-diet food samples. The percent standard deviation (% RSD) of replicate food samples was within ± 20 %. Another method was developed for determining a common OPP metabolite, 3, 5, 6-trichloro-2-pyridinol (TCP) in duplicate-diet food. The method consisted of a PLE with methanol followed by liquid-liquid partitioning, derivatization, and GC/MS analysis. Recoveries of TCP ranged from 83 to 101 % for spiked duplicate-diet food samples. The % RSD of replicate food samples was within ± 15 %. The results confirmed that these methods are reliable and robust, and that they can be used in routine analysis. In addition, a storage stability study for a common OPP, chlorpyrifos (CPF), in solid food samples was performed. The fortified (15)N-(13)C-labeled CPF was stable over 16 mo storage at -20° C in the dark. The developed analytical methods were successfully applied to 278 duplicate-diet food samples from preschool children, demonstrating that these methods are robust and suitable for routine analysis in future exposure monitoring studies.  相似文献   

15.
利用索氏提取-减量法、减量法和自行开发的高效抽提法,对一系列已知组成的含油污泥进行了油、水含量的测定。测定结果表明,高效抽提法在油、水含量的测定精度方面优于其他2种方法,对于不同组成的含油污泥,由其测定的油含量与含油污泥样品实际油含量的相对偏差均小于5%,由其测定的水含量与含油污泥样品实际水含量的相对偏差均小于7%。在测定效率方面,高效抽提法也优于其他2种方法,40 min即可完成10 g油-水-固质量比为3:2:5含油污泥中油、水含量的测定。  相似文献   

16.
利用索氏提取一减量法、减量法和自行开发的高效抽提法,对一系列已知组成的含油污泥进行了油、水含量的测定。测定结果表明,高效抽提法在油、水含量的测定精度方面优于其他2种方法,对于不同组成的含油污泥,由其测定的油含量与含油污泥样品实际油含量的相对偏差均小于5%,由其测定的水含量与含油污泥样品实际水含量的相对偏差均小于7%。在测定效率方面,高效抽提法也优于其他2种方法,40min即可完成10g油一水一固质量比为3:2:5含油污泥中油、水含量的测定。  相似文献   

17.
阳离子树脂法提取活性污泥胞外聚合物的研究   总被引:4,自引:0,他引:4  
考察了树脂法提取活性污泥中胞外聚合物(extracellular polymeric substance,EPS)的影响因素,确定了最佳的提取条件.试验结果表明,树脂量60g/g VSS,振摇频率200r/min下处理4 h,EPS的提取量达到111.20 mg/L,DNA占提取量的12.13%.该方法的重现性试验结果还表明,EPS及其各成分的相对标准偏差在2.21%~6.07%之间,能较好地满足试验要求,是一种可靠的EPS提取方法.  相似文献   

18.
For the routine measurement of acid volatile sulphide (AVS) in floodplain lake sediments, an earlier published diffusion method was adapted and optimised. We evaluated the effect of reaction time, sample weight and passive sample aeration on AVS recovery, and determined the method's reproducibility. The optimal reaction time was 4 h. Losses of AVS due to sample aeration did not occur within 15 min of sample-air contact. Relative standard deviation was <2.5% for known sulphide solutions, was between 10% and 15% for AVS concentrations in sediments and <12% for SEM concentrations in sediments, generally. Sediment samples with known SEM and AVS content were used to compare results of the developed method with the purge-and-trap method. There is a good agreement with the purge-and-trap method for SEM concentrations. AVS concentrations measured with the diffusion method are higher than with the purge-and-trap method. We conclude that the adapted diffusion method is well suited for the routine measurement of AVS concentrations in floodplain sediments.  相似文献   

19.
Zhang Y  Zhu YX  Kwon KK  Park JH  Kim SJ 《Chemosphere》2004,55(3):389-394
To study the biodegradation rate of pyrene dissolved in liquid medium supplemented with mineral salts, a synchronous fluorimetry (SF) method was established. The limit of detection for pyrene dissolved in mineral salts medium (MSM) was determined as 0.19 ng/ml with a relative standard deviation of less than 1.3% (n = 9). The pyrene degrading rates of four bacterial strains were investigated using this method under the same experimental conditions. The degradation rates of the three active strains ranged from 76% to 87% after a 14-h incubation. The results were confirmed by the gas chromatography with a flame ionized detector (GC/FID) method. This implies that pyrene degradation can be directly monitored by the SF method without the solvent extraction of samples. The advantages of SF are that it is less laborious, faster, and less expensive than the GC/FID determination method with solvent extraction. The SF method provides a new tool for studying the degradation of polynuclear aromatic hydrocarbons (PAHs) in the natural environment and under experimental conditions.  相似文献   

20.
采用预氧化 混凝沉淀法处理制浆造纸废水。研究了以氯化铁、聚丙烯酰胺为混凝剂 ,氢氧化钙为助凝剂的混凝沉淀法和KMnO4预氧化的最佳实验条件。实验结果表明 ,预氧化 混凝沉淀法对造纸废水的处理有较好的效果 ,其CODCr的去除率达 93.4 2 % ,比混凝沉淀法提高了 2 6 .8%。  相似文献   

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