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941.
S. Sundarapandiyan B. Ramanaiah R. Chandrasekar P. Saravanan 《Journal of Polymers and the Environment》2010,18(4):674-678
A phenolic resin that is used as syntan in leather manufacturing was degraded using Tremetes versicolor. On degradation of this resin for eight days, the reduction in biochemical oxygen demand (BOD), chemical oxygen demand (COD)
and total organic carbon (TOC) were 65.11, 76.66 and 72.94% respectively. It was found from the infra red (IR) spectra of
the samples that up to seven days the aromaticity was not perturbed however there were reductions in BOD and COD. Addition
of co-substrate starch, brought about reduction in BOD, COD and TOC by 85.36, 91.93 and 89.98% respectively. After eight days,
there observed a disturbance in the aromatic ring. The enzyme was extracted and assayed for polyphenol oxidase and laccase.
Polyphenol oxidase activity and laccase activity of the crude enzyme were found to be 31.4 and 1.67 U/mL. On ammonium sulfate
precipitation and dialysis, the polyphenol oxidase activity and laccase activity were enhanced by 1.5- and 3.2-folds respectively. 相似文献
942.
Sanchita Bandyopadhyay-Ghosh Subrata B. Ghosh Mohini Sain 《Journal of Polymers and the Environment》2010,18(3):437-442
Soy-polyol has been synthesized via a low energy two-step continuous route thus avoiding intermediate steps and chemicals.
The functional groups of soy-polyol thus produced were identified by Fourier transform infrared (FTIR) spectroscopy which
confirmed the cleavage of the double bonds, the formation of new epoxy linkages and the presence of hydroxyl groups. The change
in chemical structure and physical properties of the soy polyol was further characterized and the results indicated a successful
conversion with reduced unsaturation, increased hydroxyl number and increased viscosity. Polyurethane foam was prepared from
soy-polyol using isocyanate and thermogravimetric analysis was used to study its thermal decomposition behaviour. Multiple
transitions were identified in relation to depolymerization and bond dissociation. Density and compressive strength of the
soy-foam were found to be satisfactory. An investigation of microstructure of soy foam by scanning electron microscope and
X-ray computed tomography revealed the internal cell morphology and cell structure. 相似文献
943.
Potassium Release Kinetics and Water Retention of Controlled-Release Fertilizers Based on Chitosan Hydrogels 总被引:2,自引:0,他引:2
Controlled release fertilizer (CRF) hydrogels were prepared from poly(vinyl alcohol), poly(vinyl alcohol)/chitosan and chitosan
using glutaraldehyde as a crosslinker. Intermolecular interactions of the CRF hydrogels were elucidated using FTIR. Water
absorbency characteristics of the CRF hydrogels were also studied. It was found that the CRF hydrogels exhibited the equilibrium
swelling ratio (SR) in the range 70–300%. The water retention of soil containing the CRF hydrogels was also examined. It was
found that the CRF hydrogels increased the water retention of the soil. After 30 days, soil containing the PVA-, PVA/CS- and
CS-hydrogels showed the water retention capacities of 25%, 10% and 4%, respectively. While the soil without the CRF hydrogel
had already given off most of the water. The release behavior of potassium from the CRF hydrogels, both in deionized water
and in soil, was investigated. In soil, the potassium release mechanism from the PVA- and PVA/CS-hydrogels were non-Fickian
diffusion. On the other hand, the CS hydrogel showed, n value that was close to 1.0 corresponding to case II transport. In deionized water, all the CRF hydrogels showed small values
of release exponent (n < 0.5) indicating a quasi-Fickian diffusion mechanism. 相似文献
944.
湖北省武汉市青山区发改委 《再生资源与循环经济》2010,3(8):14-17
青山区作为全国著名的钢铁基地和老工业区,在推进钢铁、石化、环保等优势产业发展的同时,突破环境、资源限制"瓶颈",以理念创新、体制创新、机制创新和科技创新为动力,坚持规划引领,加强政府引导,突出企业主体,强化项目支撑,鼓励全民参与,全方位启动循环经济试点工作,推动了地区发展方式的转变和区域产业结构优化,为探索我国重化工聚集区走新型工业化道路提供借鉴。 相似文献
945.
探讨了潲水油水解生产混合酸工艺。直接用水作催化剂,适应成分复杂的餐饮潲水油,污水处理简单。从酸析、水洗、压力、温度、水解等几方面进行研究,得出最佳水解工艺条件,具有推广意义。 相似文献
946.
947.
乡村人居环境:人居环境科学研究的新领域 总被引:5,自引:0,他引:5
乡村人居环境是人居环境科学的重要构成部分,随着城市化的快速推进,乡村人居环境日益恶化.人居环境科学研究存在明显缺陷,即人居环境研究的"城市主义"倾向明显,忽视了乡村人居环境研究.分析了开展乡村人居环境研究的重要性和紧迫性,评述了国内外的相关研究成果,提出了乡村人居环境研究的多维视角,即基于农户空间行为的乡村人居环境研究、乡村人居环境的地域文化与发展模式研究、乡村人居环境与空间规划研究、基于"3S"技术的乡村人居环境研究、乡村人居环境的系统理论与发展战略研究. 相似文献
948.
中国能源生态足迹的时空动态特征及效应分析 总被引:1,自引:0,他引:1
运用生态足迹方法计算出1990—2007年中国能源消费的生态足迹。在此基础上,分析了能源足迹强度(EFI)、能源足迹生态压力(EPIEF)的时空动态变化特征。结果表明,近20年来我国能源足迹波动上升,能源消费结构有所改善,但煤炭足迹仍占主导,近几年又有回升趋势;能源足迹强度呈幂指数衰减,能源利用效率不断提高;EPIEF呈上升趋势,说明能源利用对自然生态系统的压力逐渐增大。在空间分布上,各省区能源足迹差异显著,能源足迹强度由西向东逐渐降低,而EPIEF则由西向东呈增大趋势。依据EPIEF指数将中国30个省区划分为能源足迹生态盈余区(EPIEF1)、生态轻度亏损区(1EPIEF5)和生态严重亏损区(EPIEF5)3种类型。 相似文献
949.
从内部营销的基本内涵出发,借鉴内部营销思想的实质精髓,将内部营销主体由企业扩展到旅游目的地,探讨了旅游目的地进行内部营销的必要性、可行性及实施的方法途径,得出旅游目的地实施内部营销将成为一种必然选择的结论,为旅游目的地营销视野的扩展和营销手段的丰富提供了一种新的参考。 相似文献
950.