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51.
52.
纤维素降解菌对农业有机废弃物发酵进行CO2施肥的作用 总被引:3,自引:0,他引:3
采用室内培养和大棚试验相结合,对分离的3种纤维素降解菌在有机废弃物发酵释放CO2中的作用及其对增加大棚CO2浓度的效果进行了研究。结果表明,分离获得的三种菌均能明显促进有机废弃物发酵CO2的释放,其中菌A和菌C的效果优于菌B;3种菌混合接种时效果最佳。在大棚栽培条件下,昼间CO2浓度大部分时间低于300μL/L,处于亏缺状态;采用棚中不接种直接发酵也可大幅提高大棚的CO2浓度,但释放的时间只有9 d左右;采用3种菌混合接种的方法棚内全天维持CO2浓度800μL/L以上的时间可达14 d以上。 相似文献
53.
Agricultural and ecological aspects of a sandy soil as affected by the application of municipal solid waste composts 总被引:1,自引:0,他引:1
J. Weber A. Karczewska J. Drozd M. Licznar S. Licznar E. Jamroz A. Kocowicz 《Soil biology & biochemistry》2007,39(6):1294-1302
We present the results of a plot experiment in which the changes in physical, chemical and physico-chemical properties of a sandy soil were examined after amending the soil with two different composts produced from municipal solid wastes. Triticale (X Triticosecale), cultivated in a 3-y monoculture, was used as a test plant. Both composts differed in their concentrations of heavy metals. Composts were applied non-recurrently in the spring before sowing, at the rates of 18, 36, and 72 t dry matter ha−1. The plots without fertilization, and those fertilized annually with mineral nitrogen (N), phosphorous (P), and potassium (K) were used as controls. Soil samples were collected 1 month after compost application, as well as each year after harvesting. Application of both composts improved soil physical properties, associated with increasing content of organic carbon (OC). Statistically significant increases of total porosity, field water capacity and amounts of plant-available water were found only in the short time after compost application. Despite the fact that soil OC content decreased with time, a C:N ratio clearly increased in the third year after compost application, which was explained by a depletion of N reserve. Both composts caused a large increase of plant-available P, K, and magnesium (Mg), which was observed during the entire period of the experiment. Beneficial changes were also observed in soil humic substances composition. These were confirmed by increased humic acids content and humic/fulvic acid ratios. Soil cation exchange capacity and base saturation increased in all plots amended with composts. This effect was still observed 1 year after compost application, while in the third year it remained significant only at the highest compost rates. Compost originating from industrial areas, even if applied in low amounts, caused a significant increase in total concentration of soil heavy metals. This fact did not result, however, in any substantial changes in soil quality with regard to heavy metals content. 相似文献
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为开发一种感官营养俱佳的保健食品,该研究以欧李、猕猴桃、胡萝卜、葡萄、柑橘5种果蔬为原料,用喷雾干燥法制备复合固体饮料(以下简称“五果粉”),后以五果粉饲喂雌性C57小鼠,测定血清指标,分析骨微结构,探究其对高脂饮食诱导的小鼠肝性骨病的预防作用,为五果粉的制作和营养保健功能提供依据。结果表明:5种果蔬的配方比例为40%欧李、20%猕猴桃、20%胡萝卜、10%柑橘、10%葡萄。添加可溶性固形物总量的40%的复合助干剂(麦芽糊精∶分离乳清蛋白=30∶10)与3%的稳定剂羧甲基纤维素钠,喷雾干燥条件:进风温度126℃、进料速度6.3m L/min、转子流量计高度44.00mm、可溶性固形物含量11.00%,在该条件下生产的五果粉集粉率60.86%。血清试验结果表明,给药组小鼠血清中骨钙素和抗酒石酸酸性磷酸酶5b的水平显著低于模型组(P<0.05);超氧化物歧化酶和谷胱甘肽过氧化物酶水平显著高于模型组(P<0.05),丙二醛水平显著低于模型组(P<0.05);谷丙转氨酶、谷草转氨酶水平显著低于模型组(P<0.05),且与空白组相比无显著差异(P>0.05);总胆固... 相似文献
56.
采用室内培养和大棚试验相结合,对分离的3种纤维素降解菌在有机废弃物发酵释放CO2中的作用及其对增加大棚CO2浓度的效果进行了研究。结果表明,分离获得的三种菌均能明显促进有机废弃物发酵CO2的释放,其中菌A和菌C的效果优于菌B;3种菌混合接种时效果最佳。在大棚栽培条件下,昼间CO2浓度大部分时间低于300μL/L,处于亏缺状态;采用棚中不接种直接发酵也可大幅提高大棚的CO2浓度,但释放的时间只有9.d左右;采用3种菌混合接种的方法棚内全天维持CO2浓度800μL/L以上的时间可达14.d以上。 相似文献
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Various methods exist for the isolation of particulate organic matter (POM), one of the soil‐organic‐matter (SOM) fractions reacting most sensitive on land‐use or soil‐management changes. A combination of density separation and ultrasonic treatment allows to isolate two types of POM: (1) free POM and (2) POM occluded in soil aggregates. POM fractions are closely linked to their biochemical function for the formation and stabilization of aggregates, therefore methods using different aggregate sizes may result in different POM fractions isolated. We evaluated two physical fractionation procedures to reveal whether they yield different POM fractions with respect to amount and composition, using grassland and arable soils with sandy‐loam to sandy–clay‐loam texture and thus low macroaggregate stability. Method I used air‐dried aggregates of <2.0 mm size and a low‐energy sonication for aggregate disruption, method II used field‐moist aggregates <6.3 mm and a high‐energy–sonication procedure for aggregate disruption. POM fractions were analyzed by elemental analysis (C, N) and CPMAS 13C‐NMR spectroscopy. With both methods, about similar proportions of the SOM are isolated as free or occluded POM, respectively. The free‐ and occluded‐POM fractions obtained with method I are also rather similar in C and N concentration and composition as shown by 13C‐NMR spectroscopy. Method II isolates a free‐ and occluded‐POM fraction with significantly different C and N concentrations. NMR spectra revealed significant differences in the chemical composition of both fractions from method II, with the occluded POM having lower amounts of O‐alkyl C and higher amounts of aryl C and alkyl C than the free POM. Due to the use of larger, field‐moist aggregates with minimized sample pretreatment, two distinctly different POM fractions are isolated with method II, likely to be more closely linked to their biochemical function for the formation and stabilization of aggregates. High‐energy sonication as in method II also disrupts small microaggregates <63 µm and releases fine intraaggregate POM. This fraction seems to be a significant component of occluded POM, that allows a differentiation between free and occluded POM in sandy soils with significant microaggregation. It can be concluded, that microaggregation in arable soils with sandy texture is responsible for the storage of a more degraded occluded POM, that conversely supports the stabilization of fine microaggregates. 相似文献
59.
秸秆生态工业建设的关键技术 总被引:16,自引:0,他引:16
目前秸秆生态工业的建设已形成了以秸秆汽爆为前提、压力脉动固态发酵作为主题技术路线的秸秆生物量全利用新的技术体系。压力脉动固态发酵新技术使生物技术在原料、技术、环保三方面都具有重大的技术突破,实现了严格意义上的纯种培养和规模性工业化生产。基于秸秆与木材在化学组成和结构差异,开发出了秸秆不加任何化学药品低压爆破清洁制浆、大麻清洁脱胶、秸秆制备腐植酸和活性低聚木糖等新一系列创新方法。 相似文献
60.
纤维素超低酸水解产物的分析 总被引:16,自引:2,他引:16
基于木质纤维素类生物质水解为人类提供乙醇等能源、化工产品的重要性,该文以定量滤纸模拟生物质的主要组分-纤维素,以其超低酸水解试验得到的最佳工况下液体产物和固体残渣为研究对象,通过高效液相色谱(HPLC)结合KS-802糖柱对产物质中糖的种类进行了划分,以GC-MS对副产物进行定性,并通过扫描电镜(SEM)及热重和工业分析元素分析对固体残渣作了从表观到内部的研究,发现纤维素超低酸水解主要生成纤维四糖、三糖和二糖等低聚糖和葡萄糖及果糖,反应副产物有糠醛、羟甲基糠醛、乙酰丙酸及一些小分子酮、醛类和酸类极性化合物,水解残渣已完全改变了原始形貌,热裂解活性增强,残留物中碳和灰分含量有较大增加,最后根据分析结果探讨了纤维素超低酸水解的反应途径,为木质纤维素类生物质水解技术的规模化利用打下基础。 相似文献