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将棕绷结构与弹簧结合,组成棕纤维床垫的中心缓冲层,再用不同的结构和材料形成多种类型的棕床垫。将这一创新设计应用于实践,生产出的产品得到市场的认可和欢迎,但受到规模量产的限制。 相似文献
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The influence of temperature, irradiance, and soil humidity on the nitrogen (N) concentration in some organs, chlorophyll in the leaves, N uptake and accumulation of dry matter in plants of winter wheat was investigated. In the plants grown under equal initial N supplement but in contrasting conditions of the evironment, the correlation between concentration of total N and chlorophyll in the leaves was absent. No interrelationship was found between concentration of total N in the leaves and accumulation of N and dry matter in the whole plants. There is a close correlation between chlorophyll in the leaves, accumulation of total N, and dry matter of the whole plant. It was concluded that chlorophyll is a more stable informative parameter for the estimation of the N uptake from the soil under different growth conditions than leaf N concentration. 相似文献
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椰子中果皮4种微量元素含量动态规律的研究 总被引:1,自引:0,他引:1
对椰子果的中果皮Fe、Cu等4种微量元素的动态变化规律进行研究,并对不同果龄及不同品种间的微量元素含量进行比较和相关性分析。结果表明,椰子果在发育阶段,中果皮Mn、Cu、Zn的含量均呈降低趋势,且与果串发育程度呈显著正相关;所测4种微量元素中Fe含量最高,Cu含量最低。本地高种椰子的中果皮Mn、Cu、Zn含量间均呈极显著的正相关;小黄椰子的中果皮Fe、Mn、Cu、Zn含量间均呈极显著正相关。相同果龄椰子果的中果皮Mn和Zn的含量在2个品种间没有显著差异。 相似文献
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Substrate components produced in the sub-tropics or tropics were combined in various proportions as substrates for the greenhouse production of ‘Big Beef’ tomato. Coir was mixed with parboiled rice hulls (PBH) or burnt rice hulls (BRH) at 0, 25, 50, 75, or 100% volume. Fruit fresh weights at equal proportions of BRH or PBH in coir were similar, with the greatest fruit yields achieved with 50 to 100% coir (0 to 50% PBH or BRH). Compared to 100% coir, PBH in coir decreased substrate container capacity and increased air porosity, while BRH in coir increased container capacity and decreased the air porosity. Pre-plant fertilisation of the PBH + coir substrates (superphosphate, gypsum, trace elements, calcium nitrate, and surfactant) increased fruit yield significantly. Substrates containing 50 to 100% coir with BRH or PBH yielded greater fruit fresh weights than was achieved in in 70% BRH + 30% gravel (a typical substrate used in the Dominican Republic), and reusing the 70% BRH + 30% gravel led to a 36% increase in fruit fresh weight. Fruit fresh weights in 100% coir or 75% coir plus 25% PBH or BRH were similar to those achieved in a commercial peat-lite. Herein we report on substrates made from tropical components that perform similarly to a peat-based substrate in the production of greenhouse-grown tomatoes. 相似文献
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This experiment was conducted to investigate the effect of coconut oil and garlic powder supplementation on digestibility of nutrients, rumen fermentation, rumen ecology, rumen microorganism and methanogen diversity. Four, 3-year old, rumen fistulated swamp buffalo bulls were randomly assigned in a 4 × 4 Latin square design to receive four dietary treatments; 7% coconut oil, 7% coconut oil with 50 g/day of garlic powder, 7% coconut oil with 100 g/day of garlic powder and non-supplemented (control). During the experiment, concentrate was offered at 0.5% of BW while rice straw was given on ad libitum basis. It was found that supplementation of 7% coconut oil had significantly influenced on total DM intake, OM, NDF and ADF digestibilites while supplementation of 7% coconut oil with garlic powder (50 and 100 g/day) were not significantly different when compared with the control. Dietary supplementations did not affect on rumen pH, NH3–N concentrations. Blood urea nitrogen (BUN) was significantly higher in supplemented groups. Total VFA concentration, proportion of acetate and acetate to propionate ratio were reduced by supplementation. Proportion of propionate was increased (P < 0.05) when supplemented with 7% coconut oil and 7% coconut oil with 100 g/day of garlic powder. Methane production was dramatically reduced (P = 0.005) in supplemented treatments and was 10% reduced in 7% coconut oil supplementation. Amylolytic and proteolytic bacteria were increased (P = 0.007 and P = 0.024) while protozoal population decreased by 68–75% (P < 0.01) by supplementation. Total bacterial population was increased by supplementation while total fungi and total methanogens were not significantly different among treatments. Percentage of cellulolytic bacterial population was not different among treatments. However, dietary supplementation reduced (P < 0.001) percentage of F. succinogenes population. However, methanogen diversity was not changed using PCR–DGGE as technique. Thirteen separate bands were found in the DGGE gel. Based on this study, supplementation with 7% coconut oil plus 100 g/day of garlic powder could be efficiently utilized in the rumen and thus, could provide good fermentation end products and improve rumen ecology for the host swamp buffaloes particularly in reducing 9% methane gas production without changing nutrient digestibilities. 相似文献