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排序方式: 共有2427条查询结果,搜索用时 31 毫秒
51.
鉴于市政道路基层工程摊铺技术的重要性,对二灰/水稳摊铺的试验段与摊铺技术进行了分析,总结了二灰/水稳摊铺机摊铺混合料作业要点,探讨了冬、雨期施工及过渡段与二次摊铺的衔接问题,以提高路基摊铺技术水平。 相似文献
52.
Agricultural residues are a promising source of biomass energy. However, agricultural residues are seasonally available and loosely distributed over large geographical areas and hence require spatio-temporal assessment. Satellite image is a handy input for such assessment and high resolution image could increase the preciseness of estimation. In the present study, rice cropland is mapped using high resolution WorldView-2 satellite image in a rural area of Assam, India. The rice cropland map in combination with agricultural statistics is then analyzed in GIS in order to assess rice straw availability for potential bioenergy generation. About 54% land of study area belongs to rice cropland, which can contribute 5360 tonnes surplus rice straw per annum (equivalent to 83,296 GJ). Potential electric power capacity from the surplus rice straw in the study area is 523.50 kW. However, at individual village level the potential varies from 4.45 kW to 28.69 kW. Considering the power crisis in India, the findings of this work are expected to assist policy makers and biomass energy developers in decision making process. Particularly, this paper generated information on village level rice straw residue availability and subsequently potential electric power capacity. Such information is limited in the India expect for few states. 相似文献
53.
Swapan Kumar Ghosh Rajib Bhattacharyya Murari Mohan Mondal Tapobrata Sanyal 《Journal of Natural Fibers》2015,12(5):457-480
In the last quarter of the twentieth century, a new class of materials, Geosynthetics, emerged prospectively leading significant innovation in the design of geotechnical and geoenvironmental systems. Geotextiles have proven to be among the most versatile and techno-economically viable ground modification materials playing a significant role in modern pavement design and maintenance techniques. With the growing environmental concern across the globe, technologists, researchers have inclined towards the natural geotextile where Jute Geotextile (JGT) is one of the potential candidates. But, JGT has been restricted mainly as underlay in road construction. Hence, there is an urgent need to design and develop a precise innovative fabric as overlay on existing pavements and other emerging civil works to stay technically and economically competitive in the global market. Such a fabric will not only prove techno-economically viable but will also reduce the carbon foot-print generation to a large extent. This paper delineates the development of Grey Jute Paving Fabric (GJPF) followed by its bituminization with suitable type and grade of bitumen to develop Bituminized Jute Paving Fabric (BJPF). The BJPF will enhance the life of the overlay thereby reducing the cost of maintenance as well as serving as a partial substitute of bitumen mastic. 相似文献
54.
Thi Ngoc Lan Thao Ngo Kung-Yuh Chiang Chiung-Fang Liu Ying-His Chang Hou-Peng Wan 《International Journal of Hydrogen Energy》2021,46(20):11269-11283
This paper investigates the hot gas temperature effect on enhancing hydrogen generation and minimizing tar yield using zeolite and prepared Ni-based catalysts in rice straw gasification. Results obtained from this work have shown that increasing hot gas temperature and applying catalysts can enhance energy yield efficiency. When zeolite catalyst and hot gas temperature were adjusted from 250 °C to 400 °C, H2 and CO increased slightly from 7.31% to 14.57%–8.03% and 17.34%, respectively. The tar removal efficiency varies in the 70%–90% range. When the zeolite was replaced with prepared Ni-based catalysts and hot gas cleaning (HGC) operated at 250 °C, H2 contents were significantly increased from 6.63% to 12.24% resulting in decreasing the hydrocarbon (tar), and methane content. This implied that NiO could promote the water-gas shift reaction and CH4 reforming reaction. Under other conditions in which the hot gas temperature was 400 °C, deactivated effects on prepared Ni-based catalyst were observed for inhibiting syngas and tar reduction in the HGC system. The prepared Ni-based catalyst worked at 250 °C demonstrate higher stability, catalyst activity, and less coke decomposition in dry reforming. In summary, the optimum catalytic performance in syngas production and tar elimination was achieved when the catalytic temperature was 250 °C in the presence of prepared Ni-based catalysts, producing 5.92 MJ/kg of lower heating value (LHV) and 73.9% tar removal efficiency. 相似文献
55.
Jiming Yin 《International Journal of Pavement Engineering》2016,17(6):528-541
To reduce costs and prevent environmental pollution in the fabrication process of straws fibrosis, a simple and efficient method of straw-reinforced asphalt concrete is proposed, which adds short-thin wheat straw pieces (SWSPs) into asphalt mixture directly. The road performances of wheat straw asphalt mixture (WSAM) are evaluated by means of three-point flexural test, rutting test, freeze thaw split test and the test of fracture toughness. The results show that when the SWSPs content is between 0.1% and 0.2%, the flexural strength of asphalt mixture increases by 23%, the dynamic stability by 48% (reaching 1592 times), fracture toughness by 27% while the rut depth decreases by 44%. It is indicated that high temperature stability of the asphalt mixture and low temperature crack resistance are intensified by adding an appropriate amount of SWSPs, and the results of freeze thaw split test manifest that the moisture susceptibility of WSAM is weaker. 相似文献
56.
57.
Rungsinee Sothornvit Chaiyaporn Sampoompuang 《International Journal of Food Science & Technology》2012,47(3):511-517
Rice straw contains cellulose as its main carbohydrate component, which is the major constituent for making rice straw paper as an alternative use of the residue. The objectives of this study were to determine a rice straw paper‐making process incorporating activated carbon (AC) and the effect of AC and the glucomannan (GLU) content on the physical and mechanical properties, including the ethylene adsorption capacity of rice straw paper containing AC. The results showed that AC was an effective ethylene scavenger, and it was possible to incorporate it into the rice straw paper‐making process. Increasing the AC content increased the ethylene adsorption capacity but decreased the strength of the AC‐rice straw paper. GLU maintained the strength of the rice straw paper but did not affect the ethylene adsorption capacity. Incorporation of 30% AC content with 0.3% GLU in the AC‐rice straw paper produced the maximum level of ethylene scavenging (77%). Moreover, AC‐rice straw paper is an environmentally friendly material owing to its reusability, and it has the potential for applications in food and agricultural packaging because it can act as an ethylene scavenger and also provide protection against mechanical damage. 相似文献
58.
In situ electrokinetic remediation of toxic metal‐contaminated soil driven by solid phase microbial fuel cells with a wheat straw addition 下载免费PDF全文
59.
数字化摊铺对限定作业时间的不停航施工而言,其作业速度快、精度高,测量人员能实时检测指导施工,在节约材料、节省劳动力、保障工程质量等方面有很强的优势,同时解决了传统人工基准架设速度慢这一难题,使不停航施工在退场清扫时间、摊铺厚度质量控制得到极大提升。 相似文献
60.