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1.
娄四维 《木材工业》1994,8(4):14-17
本文讨论了节能式炉气干燥室设计的一些技术问题,如提高自生风引力增强通风;多种传热方式并用,增强传热,降低热损失的途径等,以达到节能降耗、快速干燥的目的。  相似文献   
2.
    
Sorghum is becoming more widely recognised around the world as a valuable crop for its polyphenol antioxidant health-promoting properties and adaptation to harsh environments. The antioxidant capacity of diverse polyphenols in sorghum grain can vary with climatic conditions and genotype. To explore this further, the potential role of UV radiation on the profile and concentration of polyphenols was investigated in six diverse sorghum genotypes in a controlled environment facility using natural UV and visible radiation under either UV-transmitting or UV-blocking treatments. The polyphenol content and antioxidant activity were significantly reduced under the UV-blocking treatment, with contents of individual polyphenols differing among the genotypes. This information is valuable for sorghum breeders enabling them to select genotypes and UV growth conditions to produce sorghum grain with target levels of polyphenols and antioxidant capacity for human foods to meet the nutritional and health needs of different consumers.  相似文献   
3.
    
Improving rice yields is critical for global food security. China is a major rice-producing country having two rice cropping systems, i.e. single-season rice cropping system and a double-season system with both early- and late-season rice. There have been reports on the sink-source traits contributing to high grain yield for single- and early-season rice, but such information is limited for late-season rice. In this study, field experiments were conducted at the research farm of Guangxi University, Nanning, Guangxi Province, China in the late rice-growing season. Grain yield and sink-source traits were compared among five cultivars (Guiliangyou 2, Teyou 838, Y-liangyou 087, Teyou 582, and Yuxiangyouzhan) in 2012 and then three cultivars (Guiliangyou 2, Teyou 838, and Y-liangyou 087) in 2013. Y-liangyou 087 produced 6–26% higher grain yield than did the other cultivars. This higher grain yield was driven by improvements in sink-source capacity. Sink capacity was 8–31% higher in Y-liangyou 087 than in the other cultivars. Well-balanced relations between spikelets m?2 and grain weight was responsible for the higher sink capacity in Y-liangyou 087. The result was that Y-liangyou 087 produced 11–17% greater biomass (source capacity) than did the other cultivars. The greater source capacity in Y-liangyou 087 was mainly attributed to higher radiation use efficiency (RUE). Our study suggests that enhancing sink capacity through balanced relations between number of spikelets per unit land area and grain size, while improving source capacity through increasing RUE is a feasible way to achieve higher grain yield of late-season rice in South China.  相似文献   
4.
为了探索太阳能-水源热泵技术在设施农业领域的应用方法和发展潜力,寻求解决温室加温费用高、存在污染等问题的方法,对一种用于温室的太阳能和水源热泵联合加温系统进行了试验研究。结果表明:此项研究对太阳能-水源热泵这项新能源技术在农业领域的应用具有重要的意义,可减少连栋温室水源热泵加温系统一次性投资和运行成本,降低能源消耗,为太阳能水源热泵联合作为温室有效的加温系统提供了一定的理论依据。  相似文献   
5.
结合江苏农村住宅的能耗现状,介绍了一种适合江苏农村居室冬季的节能采暖技术太阳能地板辐射采暖技术,并系统地介绍了其工作原理和运行方式。同时结合具体施工案例以及对实测数据的分析得出了使用该技术能够大幅度降低农居能耗的结论。  相似文献   
6.
微波辐射技术在淀粉改性中的应用   总被引:4,自引:0,他引:4  
简要介绍微波技术的原理,以及目前在淀粉改性方面的应用状况及发展趋势。  相似文献   
7.
农村建设中太阳能路灯综合效益评价研究   总被引:1,自引:0,他引:1  
我国新农村建设中太阳能利用取得了快速发展,本文简要介绍了太阳能路灯系统的工作原理,结合某市循环经济示范村太阳能路灯系统的使用现状,采用费用-效益评价指标从经济、环境和社会效益3个方面对太阳能路灯系统进行综合评价与分析,得到太阳能路灯与普通路灯相比较,在经济上是可行的;安装太阳能路灯系统减少了对环境的污染,提高了可再生能源的利用价值,对于该旅游区的环境保护具有重大意义;对新农村建设新能源的利用,起到了很好的引导作用,为太阳能路灯系统大力推广提供一定的实践依据。  相似文献   
8.
Spiraea pubescens, a common shrub in the warm-temperate deciduous forest zone which is distributed in the Dongling Mountain area of Beijing, was exposed to ambient and enhanced ultraviolet-B (UV-B, 280–320 nm) radiation by artificially supplying a daily dose of 9.4 kJ/m2 for three growing seasons, a level that simulated a 17% depletion in stratospheric ozone. The objective of this study was to explore the effects of long-term UV-B enhancement on stomatal conductance, leaf tissue δ 13C, leaf water content, and leaf area. Particular attention was paid to the effects of UV-B radiation on water use efficiency (WUE) and leaf total nitrogen content. Enhanced UV-B radiation significantly reduced leaf area (50.1%) but increased leaf total nitrogen content (102%). These changes were associated with a decrease in stomatal conductance (16.1%) and intercellular CO2 concentration/ air CO2 concentration (C i /C a) (4.0%), and an increase in leaf tissue δ 13C (20.5‰), leaf water content (3.1%), specific leaf weight (SLW) (5.2%) and WUE (4.1%). The effects of UV-B on the plant were greatly affected by the water content of the deep soil (30–40 cm). During the dry season, differences in the stomatal conductance, δ 13C, and WUE between the control and UV-B treated shrubs were very small; whereas, differences became much greater when soil water stress disappeared. Furthermore, the effects of UV-B became much less significant as the treatment period progressed over the three growing seasons. Correlation analysis showed that enhanced UV-B radiation decreased the strength of the correlation between soil water content and leaf water content, δ 13C, C i/C a, stomatal conductance, with the exception of WUE that had a significant correlation coefficient with soil water content. These results suggest that WUE would become more sensitive to soil water variation due to UV-B radiation. Based on this experiment, it was found that enhanced UV-B radiation had much more significant effects on morphological traits and growth of S. pubescens than hydro-physiological characteristics. __________ Translated from Journal of Plant Ecology, 2006, 30(1): 47–56 [译自: 植物生态学报]  相似文献   
9.
浅谈给水排水工程节能节水措施   总被引:1,自引:0,他引:1  
作者针对给排水系统工程特点并依据多年设计实践,总结了几点节能节水措施;阐明了通过减少不必要的浪费,可以达到节约水资源、节约能源的目的。  相似文献   
10.
    
The solar-powered hybrid energy system has been put into practice in Hunan bamboo culm prefabricated housing and was enrolled in this study.In this paper,the experimental data which was taken from a demonstration house highlighted that this system has a high potential for integrated solar energy utilization.The average thermal efficiency of the collector was 58.68%,and the thermal conductivity coefficient of bamboo culm prefabricated composite wall was 1.075 W/(m2 K).Based on these results,bamboo culms could be used as the main structural material and heat storage slow-release flooring in the prefabricated housing.The housing was lower in energy consuming.  相似文献   
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