介绍了汽油 -液化石油气 (L PG)两用燃料发动机空燃比的调节和作者研制成功的无混合器式双蒸发器 L PG供气系统。该供气系统取消了 L PG发动机惯用的混合器 ,在原机双腔化油器的主、副腔喉管处钻孔 ,接入 L PG主供气系和 L PG加浓系 ,...介绍了汽油 -液化石油气 (L PG)两用燃料发动机空燃比的调节和作者研制成功的无混合器式双蒸发器 L PG供气系统。该供气系统取消了 L PG发动机惯用的混合器 ,在原机双腔化油器的主、副腔喉管处钻孔 ,接入 L PG主供气系和 L PG加浓系 ,从而取消了混合器 ,解决了全负荷时动力性与部分负荷时燃料经济性、排放之间的矛盾 ,取得了良好的效果。用该系统改装的汽油 - L PG两用燃料发动机 ,在燃用汽油时性能无任何变化 ,燃用 L PG时取得了动力性、燃料经济性和排放指标俱佳的效果。展开更多
Measurements of ammonium and nitrate uptakes by natural phytoplankton assemblages from Jiaozhou Bay at various combinations of ammonium and nitrate concentrations with 15N trace techniques showed that uptake rate of e...Measurements of ammonium and nitrate uptakes by natural phytoplankton assemblages from Jiaozhou Bay at various combinations of ammonium and nitrate concentrations with 15N trace techniques showed that uptake rate of either nitrogen was influenced by the presence of the other but that the influence of ammonium on nitrate uptake was much greater than, that of nitrate on ammonium uptake. The influence mechanism of ammonium on nitrate uptake manifested as competition at lower concentrations and as inhibition at higher concentrations (ammonium concentration 】0.6 umol/L), but no total inhibition appeared within the concentration.range of the experiments (0-10umol/L). The influence of nitrate on ammonium uptake seems to be a result of competition for uptake sites on the cell surface. In view of the in situ nutrient concentration in the given marine . environment, it is believed that both nitrogen sources are utilized by phytoplankton. Nitrate uptake in the presence of ammonium and ammonium uptake in the展开更多
语种识别的关键问题之一是提取语音信号中的语种鉴别性信息。近期,音素对数似然比(phone log-likelihood ratio,PLLR)的新特征被引入语种识别领域,并表现出了优异的性能。该文利用F比方法分析了PLLR特征向量各维的语种鉴别性大小,提出...语种识别的关键问题之一是提取语音信号中的语种鉴别性信息。近期,音素对数似然比(phone log-likelihood ratio,PLLR)的新特征被引入语种识别领域,并表现出了优异的性能。该文利用F比方法分析了PLLR特征向量各维的语种鉴别性大小,提出了加权音素对数似然比(weighted PLLR,WPLLR)特征,赋予PLLR特征中含有较多语种鉴别性信息的分量较高的权重。在美国国家标准技术署(National Institute of Standards and Technology,NIST)2007年语种识别测试集上的实验结果表明:相比于原PLLR特征,该文所提出的WPLLR特征在平均检测代价和等错率2个指标上都显著降低。展开更多
A Nutrient -Phytoplankton -Zooplankton（NPZD） type of ecological model is developed to reflect the biochemical process, and further coupled to a primitive equation ocean model, an irradiation model as well as a river...A Nutrient -Phytoplankton -Zooplankton（NPZD） type of ecological model is developed to reflect the biochemical process, and further coupled to a primitive equation ocean model, an irradiation model as well as a river discharge model to reproduce ecosystem dynamics in the Bohai Sea. Modeled primary production shows reasonable consistency with observations quantitatively and qualitatively; in addition, f-ratio is examined in detail in the first time, which is also within the range reported in other studies and reveals some meaningful insight into the relative contributions of ammonium and nitrate to the growth of phytoplankton in the Bohai Sea.展开更多
文摘介绍了汽油 -液化石油气 (L PG)两用燃料发动机空燃比的调节和作者研制成功的无混合器式双蒸发器 L PG供气系统。该供气系统取消了 L PG发动机惯用的混合器 ,在原机双腔化油器的主、副腔喉管处钻孔 ,接入 L PG主供气系和 L PG加浓系 ,从而取消了混合器 ,解决了全负荷时动力性与部分负荷时燃料经济性、排放之间的矛盾 ,取得了良好的效果。用该系统改装的汽油 - L PG两用燃料发动机 ,在燃用汽油时性能无任何变化 ,燃用 L PG时取得了动力性、燃料经济性和排放指标俱佳的效果。
基金Contribution No.2174 from the Intitute of Oceanology, Academia SinicaThis study is supported by the National Natural Science Foundation of China(No.39200022)
文摘Measurements of ammonium and nitrate uptakes by natural phytoplankton assemblages from Jiaozhou Bay at various combinations of ammonium and nitrate concentrations with 15N trace techniques showed that uptake rate of either nitrogen was influenced by the presence of the other but that the influence of ammonium on nitrate uptake was much greater than, that of nitrate on ammonium uptake. The influence mechanism of ammonium on nitrate uptake manifested as competition at lower concentrations and as inhibition at higher concentrations (ammonium concentration 】0.6 umol/L), but no total inhibition appeared within the concentration.range of the experiments (0-10umol/L). The influence of nitrate on ammonium uptake seems to be a result of competition for uptake sites on the cell surface. In view of the in situ nutrient concentration in the given marine . environment, it is believed that both nitrogen sources are utilized by phytoplankton. Nitrate uptake in the presence of ammonium and ammonium uptake in the
文摘语种识别的关键问题之一是提取语音信号中的语种鉴别性信息。近期,音素对数似然比(phone log-likelihood ratio,PLLR)的新特征被引入语种识别领域,并表现出了优异的性能。该文利用F比方法分析了PLLR特征向量各维的语种鉴别性大小,提出了加权音素对数似然比(weighted PLLR,WPLLR)特征,赋予PLLR特征中含有较多语种鉴别性信息的分量较高的权重。在美国国家标准技术署(National Institute of Standards and Technology,NIST)2007年语种识别测试集上的实验结果表明:相比于原PLLR特征,该文所提出的WPLLR特征在平均检测代价和等错率2个指标上都显著降低。
基金by the National Natural 0ur studies were supported Science Foundation of China under contract No.50339040the National Basic Research Program of China under contract No.2005CB422301.
文摘A Nutrient -Phytoplankton -Zooplankton（NPZD） type of ecological model is developed to reflect the biochemical process, and further coupled to a primitive equation ocean model, an irradiation model as well as a river discharge model to reproduce ecosystem dynamics in the Bohai Sea. Modeled primary production shows reasonable consistency with observations quantitatively and qualitatively; in addition, f-ratio is examined in detail in the first time, which is also within the range reported in other studies and reveals some meaningful insight into the relative contributions of ammonium and nitrate to the growth of phytoplankton in the Bohai Sea.
