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301.
Drying characteristics of Zingiber officinale (Ginger) under the open sun and direct type natural convection solar biomass (hybrid) drying were studied. It has been observed that under open sun drying conditions, the drying rate depends on the product thickness and climatic conditions. The results have been drawn for both the summer (April-May, 2004) and winter (November-January, 2003–04) months of Delhi, in India. In the hybrid drier, the ginger, with a thickness of 0.008 m, dried in 33 hours in comparison to 96 hours in open-sun drying. The overall drying efficiency of the hybrid drier was found to be 18% and 13% under summer and winter climatic conditions respectively. The loss of volatile oil content of the ginger is less in hybrid drier in comparison to open sun drying. It was found that the average drying air temperature of 60°C with average air velocity of 0.6m/sec was sufficient for the drying of ginger in the hybrid drier. Ginger quality after drying is better and drying time is less in the hybrid drier in comparison to open-sun drying. The hybrid drier is a simple device, which can be manufactured with locally available materials and can be used for drying of other spices, vegetables and fruits etc. 相似文献
302.
303.
四川省秸秆综合利用困局及对策建议 总被引:1,自引:0,他引:1
以四川省为例,分析了秸秆综合利用中5个方面的问题,提出了相应的3点对策和建议。 相似文献
304.
能源供应安全视角下中印生物质能源利用的比较 总被引:1,自引:0,他引:1
中国和印度是世界上两个人口最多的国家,中印两国作为世界上两个能源消费大国,如何满足众多人口和经济快速增长对能源的需求,以及提供安全的能源供应是中国和印度都在考虑并试图解决的紧迫问题,分析印度的生物能源利用政策对我国有重要的现实意义和参考价值。我国在1993年成为石油净进口国,1994年我国进口的原油仅为290×104t,进口依赖度为1.9%。到2009年我国石油净进口量为21 888.5×104t,进口原油的依赖度上升到了52.5%。我国日益增加的对国际石油市场的依赖对我国能源安全供应构成了极大的风险和挑战。我国在"十一五"期间,在生物质能源的利用上取得了很大的成绩。但还存在一些问题,主要问题是原料来源和成本不稳定、缺乏统筹规划、发电上网制度不完善、相关政策配套措施和实施细则不完善等因素在一定程度上影响了生物质能产业的发展。印度政府积极支持的生物质利用技术,包括利用清洁发展机制大量开发的生物质能CDM项目,这类项目大约占印度全部注册CDM项目的三分之一左右。印度从能源多元化供应的角度和扶持乡村可持续发展的角度上开发利用生物质能项目的实践是值得我国借鉴的。 相似文献
305.
选择2种代表性的潮间带大型海藻孔石莼(Ulva pertusa)和蜈蚣藻(Grateloupia filicina),采用单独培养和共同培养的方法,以生物量为主要测定指标,研究了二者种间竞争关系及这种关系在UV-B辐射增强时的响应趋势.结果表明,孔石莼和蜈蚣藻二者的种间竞争同时包含营养竞争和相生相克2种机制,试验中营养充足及营养限制的共养处理下孔石莼特定生长率是蜈蚣藻相应值的2.54和2.47倍,蜈蚣藻在竞争关系中处于劣势;UV-B辐射对单独培养的孔石莼和蜈蚣藻的生长均有抑制作用,且随着UV-B胁迫时间延长及辐射剂量的增加,抑制作用愈加显著;共同培养条件下,低剂量[1.6kJ·(m2·d)-1]、中剂量[4.8kJ·(m2·d)-1]的UV-B辐射时孔石莼虽占据竞争优势,但其种群竞争能力有弱化趋势,孔石莼和蜈蚣藻的生物量比共养对照分别下降6.81%、3.88%和10.47%、6.98%,二者的种间竞争趋向均衡;12d时高剂量[9.6 kJ·(m2·d)-1]UV-B辐射使孔石莼的生物量下降13.09%,而蜈蚣藻生物量降低更多达14.72%,从而导致孔石莼在高剂量辐射处理中的优势地位更趋于明显,因此UV.B辐射增强可改变共培养体系中孔石莼和蜈蚣藻种间竞争的关系,且对应于不同uV-B辐射剂量其表现不同;长期UV-B辐射可能会影响孔石莼和蜈蚣藻产生克生物质的代谢过程. 相似文献
306.
ZHAO Guangying LIU Jingshuang WANG Yang DOU Jingxin DONG Xiaoyong 《环境科学学报(英文版)》2009,21(10):1393-1399
An experiments were carried out with treatments di ering in nitrogen supply (0, 5 and 15 g N/m2) and CO2 levels (350 and 700
mol/mol) using OTC (open top chamber) equipment to investigate the biomass of Calamagrostis angustifolia and soil active carbon
contents after two years. The results showed that elevated CO2 concentration increased the biomass of C. angustifolia and the magnitude
of response varied with each growth period. Elevated CO2 concentration has increased aboveground biomass by 16.7% and 17.6%
during the jointing and heading periods and only 3.5% and 9.4% during dough and maturity periods. The increases in belowground
biomass due to CO2 elevation was 26.5%, 34.0% and 28.7% during the heading, dough and maturity periods, respectively. The responses
of biomass to enhanced CO2 concentrations are di ered in N levels. Both the increase of aboveground biomass and belowground
biomass were greater under high level of N supply (15 g N/m2). Elevated CO2 concentration also increased the allocation of biomass
and carbon in root. Under elevated CO2 concentration, the average values of active carbon tended to increase. The increases of soil active
soil contents followed the sequence of microbial biomass carbon (10.6%) > dissolved organic carbon (7.5%) > labile oxidable carbon
(6.6%) > carbohydrate carbon (4.1%). Stepwise regressions indicated there were significant correlations between the soil active carbon
contents and plant biomass. Particularly, microbial biomass carbon, labile oxidable carbon and carbohydrate carbon were found to be
correlated with belowground biomass, while dissolved organic carbon has correlation with aboveground biomass. Therefore, increased
biomass was regarded as the main driving force for the increase in soil active organic carbon under elevated CO2 concentration. 相似文献
307.
基于环境减灾卫星遥感数据的呼伦贝尔草地地上生物量反演研究 总被引:6,自引:2,他引:4
推动国产遥感卫星在资源环境领域中的应用对于促进我国航天事业发展、减少科研成本具有重要意义。我国近期发射的环境减灾卫星具有时间分辨率高、可获得高光谱影像的特点,在陆地资源遥感监测领域将有广阔发展空间。研究于2009年夏季获得三景呼伦贝尔草原区遥感影像和对应地面实测草地生物量信息,基于这些数据探讨了利用环境减灾卫星多光谱影像和植被指数反演草地生物量的可行性。结果表明基于影像提取的NDVI、OSAVI、MSAVI、SAVI、EVI、MTVI2、WDRVI和GNDVI等光谱指数均与草地生物量有较好的定量关系。其中,MTVI2结果最好,预测决定系数达0.61,交叉检验决定系数为0.58,均方根误差仅为58.6 g.m-2,基于MTVI2和环境减灾卫星多光谱影像可准确生成草地生物量空间分布图。 相似文献
308.
阐述了沈阳市利用生物质能源的基本情况和推进生物质颗粒燃料的优势。分析了生物质颗粒燃料在沈阳市推广应用过程中存在的问题,针对这些问题提出了对策。 相似文献
309.
310.
Controls over soil microbial biomass responses to carbon amendments in agricultural systems: A meta-analysis 总被引:1,自引:0,他引:1
Cynthia Kallenbach 《Agriculture, ecosystems & environment》2011,144(1):241-252
Soil microbial biomass (MB) facilitates key ecosystem functions such as soil aggregation and nutrient cycling and makes a substantial contribution to soil organic matter. While agricultural conversion drastically reduces MB, the use of organic amendments is an effective way to rebuild depleted MB. Yet, little is known about broad-scale, global controls over MB responses to organic inputs. We used a meta-analysis to identify the degree to which soil properties, agricultural management, and geographic location regulate MB response (carbon, Cmic; nitrogen, Nmic; and C:N ratio, C:Nmic) to animal manure-based inputs relative to inorganic fertilizers. We show that organic amendments increased Cmic by 36% and Nmic by 27% across all observations. The chemistry of amendments and their application rates were the strongest regulators of Cmic but edaphic properties were also important. C:Nmic averaged 8.6 and was not influenced by organic amendments under any conditions, providing evidence that the physiological requirements of microbes, rather than management or environmental factors, constrain their elemental stoichiometry. Our study indicates that even small quantities of organic amendments can be used to rapidly restore MB across a range of cropping systems but specific responses depend upon the type and rate of inputs as well soil characteristics. 相似文献