蘑菇培养料中微生物的研究

本文对蘑菇培养料中分离获得的霉菌、放线菌和细菌进行鉴定和对其生理、生化特性进行测定,对某些菌株在蘑菇生长过程中的作用及作用规律也作了研究.通过研究,初步认为在放线菌和霉菌中有数株菌株对蘑菇的生长有直接或间接的促进作用     

Water vapor adsorption onto activated carbons prepared from cattle manure compost (CMC)

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.     

Novel evaluation method of biodegradabilities for oil-based polycaprolactone by naturally occurring radiocarbon-14 concentration using accelerator mass spectrometry based on ISO 14855-2 in controlled compost

The biodegradabilities of poly(?-caprolactone) (PCL) powders (av. size = 180.7 μm) in controlled compost at 58 °C have been studied using the microbial oxidative degradation analyzer (MODA) based on ISO 14855-2 entitled “Determination of the ultimate aerobic biodegradability of plastic materials under controlled composting conditions - Method by analysis of evolved carbon dioxide - Part 2: Gravimetric measurement of carbon dioxide evolved in a laboratory-scale test”. The biodegradability of the PCL powders was 101.4% in a 56-day test period by the ISO method. The biodegradabilities of PCL powders have been studied using percent modern carbon (pMC) measured by accelerated mass spectrometry (AMS). Trapped CO₂ was analyzed by AMS to determine the pMC (sample) using ¹⁴C radiocarbon concentration. By using the theory that the pMC (sample) was the sum of pMC (compost) (104.88%) and pMC (PCL) (0%) as the respective ratios in the determined period, CO₂ (respiration) was calculated only from one reaction vessel. The biodegradability of PCL powders was 79.9% in a 56-day test period by the AMS method. It was found that respiration activities in the sample vessel including PCL, compost and sea sand were the same as that in the blank vessel including compost and sea sand without PCL during the active biodegradation period (0-33 day) at 58 °C. It was confirmed that respiration activities in the sample vessel were slightly higher than that in the blank vessel after active biodegradation due to the propagation of microorganisms using energy and metabolites by PCL biodegradation during those periods.     

Sorption of tributyltin in seawater by municipal solid waste compost

The use of municipal solid waste (MSW) compost as a sorbent for tributyltin (TBT) in seawater was investigated. TBT‐contaminated seawater, both artificially prepared and that collected from Msida Creek yacht marina (Malta), was allowed to percolate through untreated and water‐washed columns of compost and then analysed for organotins using gas chromatography‐flame photometric detection. About 90% of dissolved TBT ranging in concentration from about 800 to 8000 ng_Snl^?1 was sorbed by treating 500 ml solutions with 100 g untreated compost. On the other hand, no detectable breakthrough of TBT was observed from compost that had previously been washed by water to remove soluble organic matter. Breakthrough of TBT from unwashed compost is thought to be due to formation of complexes between the soluble organic matter in compost and aquated TBT, which renders the organotin more hydrophilic. The use of washed MSW compost as sorbent for the purification of TBT‐contaminated waters generated in large quantity during hull‐cleaning activities in drydocks is suggested as a mitigatory measure against the impact of TBT on the coastal marine environment. Copyright © 2001 John Wiley & Sons, Ltd.     

Pharmaceuticals and Their Main Metabolites in Treated Sewage Sludge and Sludge-Amended Soil: Availability and Sorption Behaviour

This work evaluated the availability and sorption behaviour of four pharmaceuticals and eight of their metabolites in sewage sludge and sludge-amended soil. Digested sludge and compost were evaluated. The highest levels found in digested sludge corresponded to caffeine (up to 115 ng g⁻¹ dm), ibuprofen (45 ng g⁻¹ dm) and carbamazepine (9.3 ng g⁻¹ dm). The concentrations measured in compost were even lower than in digested sludge. No compound was detected in sludge-amended soils. This fact could be due to the dilution effect after sludge application to soil. Different adsorption capacities in sludge–soil mixtures were measured for the studied compounds at the same spike concentration. In general, except for paraxanthine and 3-hydroxycarbamazepine, the metabolite concentrations measured in the mixtures were almost two-fold lower than those of their parent compounds, which can be explained by their mobility and lixiviation tendency. The log K_d ranged from −1.55 to 1.71 in sludge samples and from −0.29 to 1.18 in soil–sludge mixtures. The log K_d values calculated for compost were higher than those calculated for digested sludge. The obtained results implied that the higher organic carbon content of compost could influence soil contamination when it is applied to soil.     

Enzymatic degradations of copolymers of L-lactide with cyclic carbonates

Syntheses and biodegradation of random copolymers of L -lactide (L -LA) with trimethylene carbonate (TMC), 1,1-dimethyltrimethylene carbonate (1,1-DTMC) and 2,2-dimethyltrimethylene carbonate (2,2-DTMC) were investigated at various monomer ratios using SmMe(C₅Me₅)₂THF as an initiator at 80 °C for 24 h in toluene. Enzymatic degradation of these polymers were performed using cholesterol esterase, lipoprotein lipase, and proteinase K. Poly(TMC) was effectively biodegraded by cholesterol esterase and lipoprotein lipase, while poly(2,2-DTMC) and all the copolymers were hardly degraded using these enzymes. Biodegradations of poly(L -LA-co-TMC) (97:3) and poly(L -LA-co-2,2,DTMC) (95:5) show rapid degradations using TES buffer, a compost and proteinase K. The physical properties of these copolymers were also examined.

Enzymatic degradation of L -LA/2,2-DTMC copolymers by proteinase K in Tricine buffer (pH 8.0) at 37 °C: a 98:2, b 82:18, c 100:0, d 66:34, e 34:66, f 0:100.     

Thermal Methods of Organic Matter Maturation Monitoring During a Composting Process

The possibility to use thermal analysis for a quick characterisation of chemical changes in the organic matter of composted materials was tested. Nine samples were taken at progressive stages of maturation from the same trench of a fully automated composting plant. DSC and TG were simultaneously performed in static air conditions on whole ground composts. Progressive stages in the composting process yielded samples whose DSC traces revealed appreciable modifications in thermal patterns that agreed well with quantitative data obtained from TG measurements. The ratio between the mass losses associated with the two main exothermic reactions (R1) showed a good sensitivity in detecting the changes in the level of stabilisation during the composting process. Thermal methods seem to be a valid comparative method in evaluating the level of bio-transformation of materials during a composting process. This revised version was published online in July 2006 with corrections to the Cover Date.     

近红外漫反射光谱法快速测定畜禽粪便堆肥多组分含量

以我国22个省、市120个不同种类的畜禽粪便堆肥样品为研究对象,利用傅里叶变换近红外漫反射光谱技术和偏最小二乘回归法建立了我国畜禽粪便堆肥中水分、挥发性固体、总有机碳、总氮含量、碳氮比、酸碱度和电导率的近红外定量分析校正模型。各参数校正模型的决定系数R2分别为0.981 6,0.901 5,0.961 0,0.987 4,0.741 0,0.788 0和0.870 4;验证集决定系数R2_v分别为0.983 2,0.938 1,0.912 8,0.973 5,0.830 8,0.615 8和0.895 3。研究发现,除酸碱度近红外模型相对分析误差RPD(SD/SEP)值小于2.0外,水分、挥发性固体、总有机碳、总氮含量和电导率近红外模型的相对分析误差RPD值均大于3.0;碳氮比近红外模型相对分析误差RPD值介于2.0到2.5之间。结果表明,近红外漫反射光谱法可以快速测定畜禽粪便堆肥中水分、挥发性固体、总有机碳、总氮含量和电导率,对碳氮比的测定精度有待于进一步提高,对酸碱度的预测效果不理想。     

New insights into polylactide biodegradation from molecular ecological techniques

Molecular ecological techniques for direct identification of microbes involved in PLA degradation under aerobic composting conditions are described. Gene sequences from genera Paecilomyces, Thermomonospora, and Thermopolyspora were most abundant in the compost samples. Members of these phylogenetic lineages are therefore likely to play an important role in PLA degradation. The use of molecular ecological techniques to design cultivation strategies may also provide a new tool for identification and investigation of biodegradation mechanisms and for future development of efficient biological treatment or recycling processes for PLA and other biodegradable polymers.     

高填充可降解淀粉基聚烯烃材料的制备及其堆肥降解

制备了高填充的聚乙烯（PE）-淀粉-碳酸钙（CaCO3）三元复合材料,根据ASTM D6400标准对该材料进行了堆肥降解。采用熔体流动速率（MFI）、差示扫描量热分析（DSC）、扫描电镜分析（SEM）等方法研究了该复合材料的堆肥降解行为。结果表明：堆肥降解过程中,熔体流动速率（MFI）在堆肥1个月左右出现极小值;降解过...