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31.
关于尽早确定梅花、牡丹为我国国花的倡议书 总被引:3,自引:0,他引:3
首先对国花下了定义,再确认其本质,并提出评选原则是“约定俗成”。接着简述我国国花历史,和1982年提出“一国一花“(梅花),1988年提出“一国两花“(梅花、牡丹)及其后评选过程,然后,提出了建议以梅花、牡丹为中国双国花的理由,并附62位院士的签名名单(附专业)。 相似文献
32.
Antioxidant capacity and phenolic content of selected tropical fruits from Malaysia,extracted with different solvents 总被引:2,自引:0,他引:2
The antioxidant capacity and phenol content of three tropical fruits pulps, namely, honey pineapple, banana and Thai seedless guava, were studied. Three solvent systems were used (methanol, ethanol and acetone) at three different concentrations (50%, 70% and 90%) and with 100% distilled water. The antioxidant capacity of the fruit extracts was evaluated using a ferric reducing/antioxidant power assay and the free radical-scavenging capacity was evaluated using 2,2-diphenyl-1-picrylhydrazyl radical-scavenging assays. The efficiency of the solvents used to extract phenols from the three fruits varied considerably. The polyphenol content of Thai seedless guava was 123 to 191 gallic acid equivalents/100 g (GAE/100 g), that of pisang mas was 24.4 to 72.2 GAE/100 g, and that of honey pineapple was 34.7 to 54.7 GAE/100 g. High phenol content was significantly correlated with high antioxidant capacity. 相似文献
33.
Mukand Singh Babel Mohamed Mujithaba Mohamed Najim Rainer Loof 《Canadian Metallurgical Quarterly》2004,130(9):1032-1041
Very little work on the application of watershed modeling has been done in the tropical climatic conditions of Thailand to explore the nature of environmental problems arising from nonpoint source pollution due to agricultural activities, and to evaluate possible remedial measures and strategies. The present study attempts to verify the suitability of a nonpoint source pollution model, the Agricultural NonPoint Source model, for the Huai Nong Prong watershed in Southeastern Thailand. Extensive fieldwork was carried out to collect data and information needed for the model preparation and application. The study has revealed that simulated runoff volume, sediment, and nutrient yield from the watershed with mixed land use and relatively high slopes match favorably with observed data. For the ten rainfall events simulated, the coefficient of performance, a measure of model efficiency (equal to zero for a perfect match), was 0.09, 0.47, 0.09, and 0.03 for runoff volume, sediment yield, total nitrogen, and total phosphorus, respectively. The model, however, could not accurately simulate peak flow rates, suggesting the need for changes in the modeling approach or governing equations and relationships to calculate peak discharges in a tropical environment. 相似文献
34.
美国对转基因食品的监管分工明确,权责清晰。从转基因植物的研发到商业化,再到转基因植物食品的加工和上市,不同部门分工合作。美国的转基因植物食品的监管主要由农业部和食品药品监督管理局两个部门——农业部和食品药品监督管理局协同监管。农业部负责转基因植物的监管,主要的监管部门是农业部下属的动植物安全检疫局,食品药品监督管理局负责转基因植物食品的监管。本文对美国转基因植物食品的监管体系进行分析介绍,为我国转基因食品的监管提供参考。 相似文献
35.
R.R. Reddy K. Narasimhulu L. Siva Sankara Reddy K. Raghavendra Kumar Y. Nazeer Ahammed 《The International journal of environmental studies》2013,70(2):247-265
Measurements of surface ozone and its precursor gases (NOx and CO) have been made at a semi‐arid site Anantapur (14.62°N, 77.65°E, 331 m asl) in tropical Indian region for the period, 2001–2003. NOx and CO levels were the highest during morning and late night hours at this site. Diurnal variations of ozone concentrations varied from 25 ppbv to 50 ppbv and were observed to increase gradually after sunrise, attaining a maximum value by the evening and decreasing gradually thereafter. During monsoon months, the diurnal amplitude of ozone was found to be small (20–25 ppbv). Seasonal variation in ozone showed a pronounced maximum (40–50 ppbv) in the winter and summer. Local pollutants were major contributors to the ozone levels during this period. Ozone shows a yearly mean mixing ratio of about 35.9 ± 8.8 ppbv. The daytime concentration of CO and NOx varied between 200 to 1200 ppbv and 3 to 20 ppbv respectively for the period studied. Annual average mixing ratios of oxides of nitrogen (NOx) and CO were observed to be 3.9±0.6 ppbv and 436±64 ppbv, respectively. 相似文献
36.
In this study, hydrothermal upgrading and dewatering of raw tropical peat derived from Pontianak, West Kalimantan-Indonesia was evaluated at temperatures ranging from 150 to 380 °C, a maximum final pressure of 25.1 MPa and a residence time of 30 min. The moisture content of the raw peat was approximately 90 wt.%. Raw peat was hydrothermally upgraded without the addition of water in the laboratory scale. The yield of the solid products was between 53.0 and 99.7 wt.% and the effective calorific value of hydrothermally dewatered peat was between 17,290 and 29,209 kJ/kg following hydrothermal upgrading. In addition, the oxygen content in the solid product was varied from 38.4 to 15.6 wt.% after upgrading, while the carbon content from 55.2 to 77.8 wt.%. The hydrothermally upgraded peat fuel product also had an equilibrium moisture content of 2.3 wt.% and a maximum equilibrium moisture content of 17.6 wt.%. Upgraded peat is characteristically resistant to moisture adsorption at high humidity, which makes it promising for fuel based combustion. The change in the carbon-functional groups and their properties, as determined by FTIR and 13C NMR, are discussed in terms of the hydrothermal upgrading and dewatering process. 相似文献
37.
《Drying Technology》2013,31(6):1291-1298
ABSTRACT Five conditions of the osmo-dehydration process of banana slices, which in our previous study underwent the most adequate color parameters changes were used with the presence of EDTA added to the syrup solutions at five concentrations of 0.01, 0.05, 0.1, 0.5 and 1% w/w. EDTA presence did not change the tendency of polyphenol activity decrease during osmotic drying as well as has not effect on chroma, hue and total color difference changes. EDTA presence had an effect on L value decrease in the inner and outer part of the slice, and did not depend to osmotic dehydration conditions. It is highly recommended to use EDTA during osmotic dehydration of some fruits that would undergo undesirable darkening. 相似文献
38.
Ooi Xian Zhong Nor Aziah Abdul Aziz Azhar Abu Bakar 《Polymer-Plastics Technology and Engineering》2013,52(7):705-711
In this study, two different types of tropical fruit waste flour, rambutan waste flour (RWF) and banana waste flour (BWF), were blended with polyvinyl alcohol (PVOH) by solution casting method. The structure of the blend film was characterised by Fourier Transform Infrared Spectroscopy. The tensile strength and elongation at break of tropical fruit waste flour-filled polyvinyl alcohol were lower, but the tensile modulus was higher, than that of PVOH film. At a similar blend ratio, the tensile properties of the PVOH/RWF film were higher than the PVOH/BWF film, but the PVOH/BWF film showed higher water uptake than PVOH/RWF film. 相似文献
39.
ABSTRACT The weight and water loss of 6 mm thick pineapple slabs (one of a six part of slice) were analyzed during osmotic dehydration in sucrose solution at different temperatures (50, 60 and 70°C), sucrose concentrations (50, 60 and 70°Bx) and pH's (6, 7 and 8), in 33 experimental design. These results were fitted to a modified Azuara equation to obtain water and sucrose diffusivity results at equilibrium condition. Mean result of water diffusivity was 1.717 × 10?5 cm2/s and sucrose diffusivity varied from 2.0 to 4.6 × 10?5 cm2/s. The results of water loss at equilibrium in pineapple slabs varied between 0.6 to 0.67 g/g of initial sample weight. The results of sucrose gain at equilibrium varied between 0.15 and 0.21 g/g of initial sample weight. The results from mathematical modeling were compared to experimental results with r 2 = 0.94. 相似文献
40.
Serm Janjai 《Solar Energy》2010,84(9):1685-55
In order to investigate a potential use of concentrating solar power technologies and select an optimum site for these technologies, it is necessary to obtain information on the geographical distribution of direct normal solar irradiation over an area of interest. In this work, we have developed a method for estimating direct normal irradiation from satellite data for a tropical environment. The method starts with the estimation of global irradiation on a horizontal surface from MTSAT-1R satellite data and other ground-based ancillary data. Then a satellite-based diffuse fraction model was developed and used to estimate the diffuse component of the satellite-derived global irradiation. Based on this estimated global and diffuse irradiation and the solar radiation incident angle, the direct normal irradiation was finally calculated. To evaluate its performance, the method was used to estimate the monthly average hourly direct normal irradiation at seven pyrheliometer stations in Thailand. It was found that values of monthly average hourly direct normal irradiation from the measurements and those estimated from the proposed method are in reasonable agreement, with a root mean square difference of 16% and a mean bias of −1.6%, with respect to mean measured values. After the validation, this method was used to estimate the monthly average hourly direct normal irradiation over Thailand by using MTSAT-1R satellite data for the period from June 2005 to December 2008. Results from the calculation were displayed as hourly and yearly irradiation maps. These maps reveal that the direct normal irradiation in Thailand was strongly affected by the tropical monsoons and local topography of the country. 相似文献