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为简化矿井通风复杂风网的解算,提出将扰动法引入到风网解算中,并介绍扰动法的原理、风网解算的基本定律;给出常见的固定风压、固定风量和给定风机性能函数3种风机工况下的扰动方程矩阵表达式及详细的计算过程;对所提风网解算方法进行实例验证。结果表明:扰动法作为固定运算次数的近似方法,在工程实际允许的误差范围内,相比于以牛顿法为代表的迭代法耗时少、不依赖初值,是1种简单实用的风网解算方法。 相似文献
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某淀粉厂在原有处理工艺的基础上增加厌氧UASB及好氧CASS工艺,完善了物化处理+生化处理的最佳工艺流程。运行结果表明:用该工艺处理淀粉废水,其出水水质达到GB8978-1996《污水综合排放标准》二级排放标准。 相似文献
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晋南两熟半干旱区“粮药”(半夏)农田生态抗旱耕作模式效益研究 总被引:1,自引:0,他引:1
采用大田试验,设计冬小麦(Triticum aestivum Linn.)在春季起身后套作半夏[Pinellia ternata(Thunb.)Breit.](小麦/半夏)、冬油菜(Brassica campestris L.)收获后复播半夏[Pinellia ternata(Thunb.)Breit.](油菜-半夏)和春玉米(Zea mays L.)与半夏[Pinellia ternata(Thunb.)Breit.]间作(玉米+半夏)3种耕作模式,探讨晋南两熟半干旱区适宜半夏的粮药耕作模式。结果表明:与油菜-半夏、玉米+半夏耕作模式相比,小麦/半夏耕作模式经济产量最高,生态效益最好;不同半夏品种中,西河半夏(原产地温度相对最低)产量最高,新绛半夏(原产地温度相对较高)产量最低。表明半夏适宜于从低温地区引种到高温地区栽培,可提高产量。与商洛半夏和新绛半夏相比,西河半夏分别增产19.1%和41.9%;小麦/半夏耕作模式为最佳粮药耕作模式,其半夏产量与油菜-半夏和玉米+半夏耕作模式相比,分别增产53.4%和70.8%。 相似文献
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Yue Shengjuan Guo Mengjing Zou Penghui Wu Wei Zhou Xiaode 《Environmental science and pollution research international》2021,28(14):17506-17518
Environmental Science and Pollution Research - Photovoltaic power generation is an important clean energy alternative to fossil fuels. To reduce CO2 emissions, the Chinese government has ordered... 相似文献
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滑坡稳定性评价的非线性方法 总被引:5,自引:5,他引:5
在全面分析了滑坡稳定性评价方法的基础上 ,确定了影响滑坡稳定性的相关因素 ,应用BP神经网络建立了滑坡稳定性评价模型。应用表明 ,该模型精度很高。将该模型用于预测红石包和谭家评滑坡稳定性 ,其结果与实际相符。 相似文献
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The effects of allochthonous dissolved organic matter (DOM) on the growth and photosynthesis of Phaeodactylum tricornutum
were investigated. P. tricornutum incubated in f/2 medium was exposed to DOM additives, which were extracted from the plant and
sediment samples of a salt marsh in North Branch of the Yangtze estuary, China. During 12 days incubation, the chlorophyll fluorescence
parameters of P. tricornutum were measured by a Phyto-PAM phytoplankton analyzer. Spectral properties of DOM in algae filtrates
were also observed. The concentrations of chlorophyll a, active chlorophyll a, and the maximum quantum yield of photosystem II
significantly decreased after four days of incubation, suggesting that the growth and photosynthetic e ciency of P. tricornutum were
inhibited. After adding sediment-DOM extract, both a250/a365 (the ratio of the absorption coe cients at 250 and 365 nm) and S values
(spectral slope coe cients) of algae filtrates declined in the first two days, which demonstrated a loss of low molecular weight DOM.
Parallel factor analysis of fluorescence spectra of DOM in algae filtrates revealed that DOM could be classified into two humic-like
and two protein-like components. The fluorescence intensity of tyrosine-like component originating from algae increased significantly
during incubation. This study supports the hypothesis that allochthonous DOM derived from salt marsh plant and sediment have a
strong influence on the adjacent aquatic ecosystems. 相似文献