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排序方式: 共有198条查询结果,搜索用时 359 毫秒
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Arturo Pardo‐Giménez José E. Pardo‐González Diego C. Zied 《International Journal of Food Science & Technology》2011,46(4):787-792
The present work evaluates of harvested mushroom and viability of Agaricus bisporus growth in several casing materials based on spent mushroom substrate. The experiment consisted of eight casing layer, which six were made with spent mushroom substrate. The results confirm the usefulness of reincorporating the spent substrate in new cultivation cycles as an ingredient of casing mixtures. In general, biological efficiency was high, three of the SMS based‐casings surpassing the threshold value of 100 kg 100 kg?1 of compost. The high electrical conductivity of mixtures containing a large proportion of spent substrate limits the extent to which it can be used, although mixing it with other materials (such as peat) reduces these values to acceptable levels. In short, it makes economic and environmental sense to reuse spent mushroom substrate as an ingredient of alternative casing materials. 相似文献
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E. Bane Kroeger 《国际露天开采、回填与环境杂志》2013,27(3):215-222
ABSTRACT Plane failure in rock and soil slopes is usually caused by the intersection of a discontinuity plane with a slope face. This discontinuity can be any one of many different types of faulting, fracturing, bedding, foliation, schistosity, etc. Generally, these discontinuities are weaker than the surrounding intact material and provide a surface along which movement can occur. When designing a stable slope, it is often desirable to find the worst conditions for a particular slope configuration and base the final design around those conditions. The worst case for most dry slopes usually includes a tension crack at an unknown location. This paper focuses on plane failure analyses of compound slopes using limit equilibrium techniques. It provides new equations to calculate the position of tension cracks in compound slopes. 相似文献
135.
蘑菇渣资源的生态高值化利用研究进展 总被引:11,自引:0,他引:11
蘑菇渣是食用菌产业的固体废物,磨菇渣中含有食用菌的代谢产物:包括糖类、有机酸类、酶和生物活性物质,数量庞大的微生物群落以及残留的菌丝体,蘑菇渣具有生态高值化利用的潜力,结合国内外文献,介绍了磨菇渣在农业与生态环境修复领域应用研究进展。 相似文献
136.
在引入Faby菌扩大菌种的基础上,进行了花卉和野生植物秸杆好氧推肥实验,探讨过程的最佳工艺控制条件,为实现秸杆资源的综合利用,生产高效有机肥,促成平衡施肥,土壤改良,面源污染控制而奠定基础。 相似文献
137.
玉米秸秆添加比例对污泥好氧堆肥质量的影响 总被引:1,自引:0,他引:1
为探讨不同物料配比对污泥堆肥质量的影响,将城市污泥和玉米秸秆按照(w/w,以干重计)0.5∶1、1∶1和2∶1的比例进行35 d高温好氧堆肥,研究了堆肥过程中温度、有机碳(TOC)、C/N、总氮(TN)、速效磷、速效钾、腐殖酸(HAs)和种子发芽率(GI)的变化规律。结果表明:3个处理堆体温度都能达到国家无害化标准;随着堆肥进行,有机碳和C/N逐渐下降,下降幅度与初始物料有机碳和C/N呈正相关;堆肥结束时,总氮和速效钾都有所增加;速效磷开始略有波动,最后呈增加趋势;腐殖酸(HAs)总量没有大幅增加;3个处理种子发芽率都不断提高,到堆肥结束时均达到60%以上;堆肥产品氮、磷、钾和腐殖酸含量随着污泥比例升高而增加。 相似文献
138.
E. Frossard P. Skrabal S. Sinaj F. Bangerter O. Traore 《Nutrient Cycling in Agroecosystems》2002,62(2):103-113
Switzerland yearly produces more than 260,000 Mg of compost, two thirds of which is recycled in agriculture and horticulture. This research was undertaken to examine the forms and availability of inorganic P (Pi) in Swiss composts made from solid kitchen and garden wastes using the isotopic exchange kinetic technique, a sequential Pi extraction and magic angle spinning (MAS) solid-state 31P nuclear magnetic resonance (NMR) spectroscopy. The different approaches described in this paper demonstrate the presence of a complex mixture of Pi species in the studied composts. Isotopic exchange experiments and sequential extraction showed that these composts contained relatively large concentrations of rapidly available Pi. Significant correlations were observed between the concentration of water-soluble Pi (Cp), and the total N, C and P content of composts suggesting that organic substances partly controlled the amount of rapidly available Pi. Significant correlations were observed in alkaline composts between the amount of Pi which can not be exchanged within 3 months and the total P and Ca content. In alkaline composts solid-state MAS 31P NMR results suggested the presence of a range of slightly soluble and poorly crystallized Ca-P compounds such as apatites or octacalcium phosphates and of organic P compounds. The slowly or non-exchangeable Pi present in these composts could therefore be bound to Ca in the form of apatites or octacalcium phosphates. 相似文献
139.
基于BP神经网络的堆肥物料抗剪强度预测模型 总被引:1,自引:0,他引:1
针对目前传统方式采集堆肥物料抗剪强度数据过程中环境恶劣、数据采集困难、试验误差大等问题,提出一种基于BP神经网络的抗剪强度预测模型。通过现场试验得到堆肥物料抗剪强度和堆体高度、温度、含水率、密度等参数共39组有效数据,以其中35组作为训练样本,其余4组用于评价模型的预测性能。结果表明,该模型预测值与实测值的平均误差为11. 35%,基于BP神经网络的抗剪强度预测模型具有较高的预测精度,为抗剪强度的预测提供了一种新方法。 相似文献
140.