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Zhang F Gu W Xu P Tang S Xie K Huang X Huang Q 《Waste management (New York, N.Y.)》2011,31(6):1333-1338
Composting is the biological degradation and transformation of organic materials under controlled conditions to promote aerobic decomposition. To find effective ways to accelerate composting and improve compost quality, numerous methods including additive addition, inoculation of microorganisms, and the use of biosurfactants have been explored. Studies have shown that biosurfactant addition provides more favorable conditions for microorganism growth, thereby accelerating the composting process. However, biosurfactants have limited applications because they are expensive and their use in composting and microbial fertilizers is prohibited. Meanwhile, alkyl polyglycoside (APG) is considered a “green” surfactant. This study aims to determine whether APG addition into a compost reaction vessel during 28-day composting can enhance the organic matter degradation and composting process of dairy manure. Samples were periodically taken from different reactor depths at 0, 3, 5, 7, 14, 21, and 28 days. pH levels, electrical conductivity (EC), ammonium and nitrate nitrogen, seed germination indices, and microbial population were determined. Organic matter and total nitrogen were also measured.Compared with the untreated control, the sample with APG exhibited slightly increased microbial populations, such as bacteria, fungi, and actinomycetes. APG addition increased temperatures without substantially affecting compost pH and EC throughout the process. After 28 days, APG addition increased nitrate nitrogen concentrations, promoted matter degradation, and increased seed germination indices. The results of this study suggest that the addition of APG provides more favorable conditions for microorganism growth, slightly enhancing organic matter decomposition and accelerating the composting process, improving the compost quality to a certain extent. 相似文献
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Mao Ye Mingming Sun Ni Ni Yinwen Chen Zongtang Liu Chengang Gu Yongrong Bian Feng Hu Huixin Li Fredrick Orori Kengara Xin Jiang 《Environmental science and pollution research international》2014,21(13):7785-7796
The present study was conducted to investigate the anaerobic biodegradation potential of biostimulation by nitrate (KNO3) and methyl-β-cyclodextrin (MCD) addition on an aged organochlorine pesticide (OCP)-contaminated paddy soil. After 180 days of incubation, total OCP biodegradation was highest in soil receiving the addition of nitrate and MCD simultaneously and then followed by nitrate addition, MCD addition, and control. The highest biodegradation of chlordanes, hexachlorocyclohexanes, endosulfans, and total OCPs was 74.3, 63.5, 51.2, and 65.1 %, respectively. Meanwhile, MCD addition significantly increased OCP bioaccessibility (p?<?0.05) evaluated by Tenax TA extraction and a three-compartment model method. Moreover, the addition of nitrate and MCD also obtained the highest values of soil microbial activities, including soil microbial biomass carbon and nitrogen, ATP production, denitrifying bacteria count, and nitrate reductase activity. Such similar trend between OCP biodegradation and soil-denitrifying activities suggests a close relationship between OCP biodegradation and N cycling and the indirect/direct involvement of soil microorganisms, especially denitrifying microorganisms in the anaerobic biodegradation of OCPs. 相似文献
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Hui Wang Chong-qing Wang Jian-gang Fu Guo-hua Gu 《Waste management (New York, N.Y.)》2014,34(2):309-315
The surface free energy, surface tension and contact angles were performed to investigate the properties of wetting agents. Adsorption of wetting agents changes wetting behavior of polymer resins. Flotability of polymer materials modulated by wetting agents was studied, and wetting agents change significantly flotability of polymer materials. The flotability decreases with increasing the concentration of wetting agents, and the wetting ability is lignin sulfonate (LS) > tannic acid (TA) > methylcellulose (MC) > triton X-100 (TX-100) (from strong to weak). There is significant difference in the flotability between polymer resins and plastics due to the presence of additives in the plastics. Flotation separation of two-component and multicomponent plastics was conducted based on the flotability modulated by wetting agents. The two-component mixtures can be efficiently separated using proper wetting agent through simple flotation flowsheet. The multicomponent plastic mixtures can be separated efficiently through multi-stage flotation using TA and LS as wetting agents, and the purity of separated component was above 94%, and the recovery was more than 93%. 相似文献
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The food of four species of asellote isopods (Crustacea, Malacostraca), Haploniscus
rostratus, Haploniscus unicornis, Acanthocope galatheae and Betamorpha fusiformis, was evaluated by analysis of their gut contents. The isopods were sampled at several stations on the abyssal plains of Guinea
Basin, Angola Basin and Cape Basin (southeast Atlantic), the Weddell Sea abyssal plain and the Antarctic continental slope
during the DIVA and ANDEEP expeditions in 2000, 2001 and 2005. While all species had mineral particles in their guts and mucus
material was the most frequent food item, the remaining gut contents differed among species. Betamorpha fusiformis fed mostly on phytodetritus, especially in the Southern Ocean basins and ingested along with it whole calcareous foraminifers.
Acanthocope galatheae showed some differences in gut contents between basins, but in the Guinea Basin, the contents were to a large extent stercomata,
i.e., waste pellets of soft-walled foraminifers, i.e., the Komokiaceae. Indications were that the haploniscids were feeding
on detritus and agglutinating foraminifers (stercomata). This indicates spatial differences in food availability for this
diverse group of deep-sea isopods and the importance of poorly known foraminiferal groups, like the Komokiaceae, as a food
source in the deep sea. 相似文献
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Heinz G. Stefan .Ruochuan Gu 《Journal of the American Water Resources Association》1991,27(6):967-978
ABSTRACT: Forced artificial mixing of temperature-stratified ponds, or small lakes or reservoirs, by liquid jets can enhance water quality and can also be energy efficient. Based on previous studies of jet mixing mechanics of stratified water bodies, a conceptual design approach is presented. The main “operational” and “system” design parameters are considered in the proposed method. Using minimization of a total cost estimate as a criterion, an iterative method for the selection of the number and size of the jets is developed and illustrated. 相似文献
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