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1.
在预培红壤中加入定量的有机肥和葡萄糖及不同浓度的Cu,25℃培养14d,测定了土壤微生物生物量C(Cmic),N(Nmic)。结果表明,存在有机肥和葡萄糖时,土壤中Cmic和Nmic随着Cu浓度的增加而降低;Cmic/Nmic随着Cu浓度的增加而增大。施加有机肥和葡萄糖的土壤中,在所有Cu处理浓度下,土壤中Cmic和Nmic均比未加有机物质处理高,特别是有机肥处理中土壤Cmic和Nmic均比其它处理高得多,说明有机肥可明显减轻Cu对土壤微生物生物量的毒性,同时也说明有机肥可提供微生物N源。不含Cu时,加入有机肥和葡萄糖导致土壤中Cmic和Nmic增加,其中有机肥明显。  相似文献   
2.
Abstract

Human and animal excrements, in particular manure, stand for a significant and undisputable source of plant nutrients and renewable energy. In Europe, only 36% of P-inputs to soils originate from primary resources (rock phosphate) whereas 63% come from animal and human excretions applied to cropland as manure, digestion residues and sewage sludge. Simultaneously these waste flows represent a potential hazard to human health and aquatic bodies because of pathogens and eutrophication. Management of these waste flows is far from being sustainable, in part due to the lack of efficient processing technologies. A cooperative InnoEnergy—EIT financed KIC Knowledge and Innovation Community—research project pursues development and demonstration of highly efficient technologies to overcome the constraints and to yield renewable phosphate fertilizers and energy from waste flows that may have a combined technical energy potential of 3,600 PJ/year and an annual phosphate recovery potential of 4.5–5.5 million tonnes (as P2O5) in Europe.  相似文献   
3.
研究并优化了同时分析畜禽粪便中14种抗生素(四环素、磺胺、氟喹诺酮和大环内酯类)的加速溶剂萃取参数、固相富集净化程序、以及高效液相色谱分离和检测条件。结果表明,以1%乙酸(pH 2.6)作为流动相,在270 nm的检测波长下,14种抗生素能达到基线分离。3倍信噪比下,四环素、磺胺、氟喹诺酮和大环内酯类抗生素的检出限分别为35~90μg/kg,12~28μg/kg,9~17μg/kg及19μg/kg。加标浓度在1和10μg/g时,畜禽粪便样品经过50%甲醇的柠檬酸盐缓冲溶液提取,HLB固相萃取柱富集净化后,四环素、磺胺、氟喹诺酮和大环内酯类抗生素的回收率分别达到了58%~75%和66%~83%,74%~93%和91%~101%,74%~80%和80%~88%,85%和68%,相对标准偏差分别为6.2%~10.7%和7.8%~13.6,2.6%~10.2%和4.4%~13.2%,6.1%~12.5%和8.3%~14.6%,10.6%和12.3%。采用此方法对辽宁省部分规模化养殖场的猪粪、牛粪和鸡粪样品进行了检测。4类抗生素都有检出,浓度范围分别为0.75~22.34 mg/kg,0.10~1.71 mg/kg,0.38~4.46 mg/kg和0.23~0.35 mg/kg。  相似文献   
4.
We describe a selective pressurized liquid extraction (SPLE) method, followed by gas chromatography–mass spectrometry (GC–MS), for the simultaneous extraction and clean-up of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in sheep liver tissue samples. The on-line clean-up of liver tissue by SPLE was tested using differing amount of acid-modified silica (sulphuric acid:silica gel, 1:2, w/w), the most effective amount being 20 g. Different extraction solvents (iso-hexane and dichloromethane), either alone or in various combinations, were used to extract these target compounds from spiked liver samples. Variables affecting the SPLE extraction efficiency, including temperature, pressure, number of extraction cycles and static extraction time were studied; the optimum parameters were 80 °C, 10.3 MPa, 2 cycles and 5 min, respectively. The SPLE based method was compared with more traditional Soxhlet, off-line PLE, ultrasonic and heating extraction methods. Overall the mean percentage recoveries for all target chemicals using SPLE were 86–103% (n = 3, SD < 9%), and compared favourably with the Soxhlet (63–109%, n = 3, SD < 8%), off-line PLE (82–104%, n = 3, SD < 18%), ultrasonic (86–99%, n = 3, SD < 11%) and heating (72–102%, n = 3, SD < 21%) extraction methods. The limits of detection of the proposed method were 5–96 pg g−1 and 2–29 pg g−1 for the different PBDE and PCB chemicals studied, respectively. The outputs of the proposed method were linear over the range from 0.02 to 30 ng g−1, for all PCB and PBDE congeners except for PBDE 100 and 153 (0.05–30 ng g−1) and PBDE 183 (0.1–30 ng g−1). The method was successfully applied to sheep liver samples for the determination of the target PBDE and PCB compounds.  相似文献   
5.
Activated carbons were prepared from cattle manure compost (CMC) using zinc chloride activation. The structural and surface chemical characteristics of CMC-based activated carbons were determined by N2 adsorption-desorption and Boehm titration, respectively. The water vapor adsorption properties of the prepared activated carbons with various pore structure and surface nature were examined, and the mechanism of water adsorbed onto activated carbon was also discussed. The results show that the adsorption of water vapor on carbons begins at specific active sites at low relative humidity (RH), followed by micropore filling at medium RH through the formation of pentamer cluster of water molecules in the narrow micropores. The water vapor adsorption capacity of activated carbon is predominantly dependent on its pore volume and surface area. Although capillary condensation is not the mechanism for water adsorption onto activated carbon, water can adsorb on narrow mesopore to some extent.  相似文献   
6.
近红外光谱技术(NIRS)以其低成本、高效、环保、无损的优势在日粮和畜产品品质分析中得到广泛应用。饲料品质参数(如粗蛋白)的获取对于日粮营养的合理搭配不可或缺,传统的近红外光谱技术将日粮的近红外光谱与日粮品质参数的化学测定值进行回归,建立预测模型对日粮品质参数进行检测。然而,在放牧条件下日粮近红外光谱的难以获取限制了这一传统建模方法在动物营养中的应用。作为动物代谢性产物,动物粪便不仅包含有日粮信息也携带有动物自身信息。近年来,基于动物粪便近红外光谱和日粮信息(日粮植物学成分、化学成分及其消化率)建立的回归模型,也已被用于动物日粮信息的检测。简要介绍F.NIRS在动物性别、品种鉴定及繁殖和寄生虫感染状态检测中的应用。NIRS在动物粪肥分析中的应用结果表明NIRS能够对粪肥中主要成分含量进行快速分析。尽管F.NIRS预测准确性有待提高,但已显示出其作为快速、有效的分析工具用于检测日粮品质参数及动物生理状态的潜力。相关的英文评述性文章业已出版,但在中国F.NIRS的研究和应用非常欠缺。期望本文的呈现有助于F.NIRS在国内的发展。推荐将NIRS作为快速分析工具用于对粪肥主要成分(DM,OM,TS,VS,TN,TKN和NH3-N)含量进行检测。  相似文献   
7.
采用改进的BCR连续提取,利用原子吸收光谱法测定了内蒙古草地施用羊粪试验11年后土壤中Mn组分。试验设置5个处理,分别施干羊粪0,50,250,750和1 500 g·m-2·yr-1。结果表明,以四步加和法与强酸直接消煮法测定的全Mn含量作为回收率,各处理回收率为91.4%~105.9%,加标回收率为97.2%~102.9%。长期大量施有机肥可提高0~5 cm土层植物可利用的交换态Mn含量47.89%,但还原态Mn和全Mn含量显著下降。施肥对0~5 cm土层Mn形态影响大于5~10 cm土层。研究结果对于土壤微量元素形态测定及草地养分管理具有一定的参考价值。  相似文献   
8.
绿肥对华北潮土土壤可溶性有机物的影响   总被引:3,自引:0,他引:3  
在华北潮土上种植不同绿肥,于绿肥翻压前原位采集其地上部及土壤样品,进行56d的绿肥翻压模拟试验。设毛叶苕子(Vicia villosa Roth.)、二月兰(Orychophragmus Violaceus L.)、黑麦(Secale cereale L.)三个绿肥处理和无绿肥对照处理,分析培养过程中土壤可溶性有机物(DOM)组分及其紫外-可见光谱参数的变化,以探究绿肥对土壤DOM的影响。种植和翻压绿肥增加土壤可溶性有机碳(DOC)、总有机酸碳(TOAs)和总碳水化合物碳(TCs)含量,三者的变化趋势一致,各处理均在培养第1 d上升至峰值后迅速下降。毛叶苕子提高DOC和TOAs的效果最好,最高比对照增加114.01%(培养第1d)和109.10%(培养第14 d)。黑麦提高TCs的效果最好,最高比对照增加323.18%(培养第42 d)。种植和翻压绿肥增加土壤可溶性有机氮(DON)含量,与DOC变化趋势不同,各处理在培养第1 d上升后迅速下降一段时间后又迅速上升。毛叶苕子提高DON的效果最好,最高比对照增加305.83%(培养第42d)。绿肥增加了SUVA254,SUVA260,SUVA272,SUVA280,SAUC240-400,降低了A250/A365和A240/A420。紫外-可见光谱参数的主成分分析显示SUVA254,SUVA260,SUVA272,SUVA280间有很高正相关性,A250/A365和A240/A420间亦有很高正相关性,SAUC240-400是这些参数中表征DOM性质的关键因子。综上结果表明,种植翻压绿肥增加了土壤DOM含量,提高了土壤DOM的芳香性、疏水性、腐殖化程度、平均分子量,增加了土壤DOM的稳定性。  相似文献   
9.
安国荣  张明  周冰  曹晓武 《光谱实验室》2012,29(3):1912-1914
实验了电感耦合等离子体-质谱法(ICP-MS)测定羊板粪中的重金属元素Cr、As、Hg、Cd、Pb,优化了仪器的测定条件。方法检出限分别为:Cr 0.39、As 0.12、Hg 0.24、Cd 0.090、Pb 0.49ng/mL,方法精密度RSD:4.9%—14.3%,加标回收率92.0%—110.0%。方法适用于类似有机物样品中重金属元素的检测。  相似文献   
10.
A multiresidue method was developed for the determination of 19 emerging organic contaminants (pharmaceutical drugs, personal care products, and bisphenol A) in poultry manure. Lyophilized samples of manure were extracted by ultrasound‐assisted matrix solid‐phase dispersion and the extracts were analyzed by gas chromatography with tandem mass spectrometry after derivatization. Analysis of spiked poultry manure samples, at levels ranging from 25 to 150 ng/g, gave satisfactory recovery results for all the compounds, with values from 67 to 106%. The developed procedure provided detection limits that ranged from 0.9 to 2.2 ng/g. Finally, the validated method was applied to poultry manure samples collected from 23 poultry farms in Spain. Salicylic acid was found in most of the samples analyzed at levels up to 2501 ng/g, whereas, methyl paraben, orthophenylphenol, ibuprofen, paracetamol, and carbamazepine were detected at levels up to 250 ng/g. Composting of manure showed an important decrease in the levels of the detected contaminants.  相似文献   
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