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Search Results: 1 - 10 of 456257 matches for " <br>刘宇锋 "
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Effect of irrigation method and fertilization dose on photosynthetic physiology of super rice
灌溉方式与施肥水平对超级稻光合生理的影响

LIU Yu-Feng,LI Fu-Sheng,<br>,李伏生
中国生态农业学报 , 2013,
Abstract: To investigate the effect of irrigation and fertilization on photosynthetic physiology of super rice, a pot experiment was conducted using super rice "Zhongzheyou 1" as experimental crop. The study analyzed the photosynthetic physiology parameters net photosynthetic rate,Pn; intercellular CO2 concentration, Ci; photosynthetic light response curve and photosynthetic pigment contents of chlorophyll a (Chl a), chlorophyll b (Chl b), carotenoid (Car), total chlorophyll content (TCC)] of rice under three irrigation methods controlled irrigation (CIR), intermittent irrigation (IIR) and flood irrigation (FIR)] and three fertilization levels non-fertilization (F0), low fertilization (FL) and high fertilization (FH)]. It also conducted correlation analysis for Pn and chlorophyll contents. The results showed that compared with FIR, CIR and IIR treatments (saving-water irrigation methods) significantly increased Pn. It, however, failed to significantly enhance Ci at the jointing, heading and milking stages. Both CIR and IIR increased light saturation point (LSP) by 9.2%~36.8% at the jointing and heading stages and apparent quantum yield by 6.7%~31.5% respectively at the three growth stages, while they decreased light compensation point by 3.2%~12.8% at the jointing, heading and milking stages. Compared with FIR, CIR respectively increased the contents of Chl a, Chl b, Car and TCC by 19.1%~76.3%, 44.5%~98.5%, 31.5%~117.4% and 45.4%~145.0% at the jointing, heading and milking stages. IIR treatment respectively enhanced the contents of Car and TCC by 4.2%~45.8% and 31.5%~117.4% at the three growth stages. Under the three irrigation treatments, photosynthetic indices and photosynthetic pigment contents were higher under fertilization than non-fertilization treatments. High fertilization also resulted in higher photosynthetic indices and photosynthetic pigment content than low fertilization. Correlation analysis showed significant correlation between Pn and photosynthetic pigments contents, which correlations were influenced by growth stages. CIR and IIR improved photosynthetic capacity under strong light, and adaptability to weak light; and significantly increased light utilization rate. Compared with FIR, CIR and IIR increased photosynthetic pigment content but delayed photosynthetic pigment degradation. It was concluded that CIR and IIR treatments enhanced photosynthetic capacity, improved the photosynthetic light response curve and increased photosynthetic pigment contents. In terms of fertilization rate, high fertilization increased photosynthetic capacity of "Zhongzheyou 1" under saving-water irrigation treatments.
Self-Aligned InGaP/GaAs Power HBTs with a Low Bias Voltage
低偏置电压工作的自对准InGaP/GaAs功率异质结双极晶体管(英文)

Zheng Liping,<br>郑丽萍,孙海,狄浩成,,王素琴,,吴德馨
半导体学报 , 2004,
Abstract: 介绍L 波段、低偏置电压下工作的自对准In Ga P/ Ga As功率异质结双极晶体管的研制.在晶体管制作过程中采用了发射极-基极金属自对准、空气桥以及减薄等工艺改善其功率特性.功率测试结果显示:当器件工作在AB类,工作频率为2 GHz,集电极偏置电压仅为3V时,尺寸为2×(3μm×1 5 μm)×1 2的功率管获得了最大输出功率为2 3d Bm,最大功率附加效率为4 5 % ,线性增益为1 0 d B的良好性能
Sporulation, competence development and biopesticide activity of a Bacillus subtilis mutant
生防菌Bs-916突变菌株M49芽胞形成和感受态形成能力

Xiaoyu Wang,Chuping Luo,Yongfeng Liu,Youzhou Liu,Yafeng Nie,Zhiyi Chen,<br>王晓,罗楚平,,邮洲,聂亚,陈志谊
微生物学报 , 2009,
Abstract: 摘要:生防枯草芽胞杆菌Bs-916(Bacillus subtilis)在水稻纹枯病的防治上效果显著。应用离子注入突变对Bs-916进行了突变,获得了一系列的突变菌株。其中突变菌株M49,其表面活性素Surfactin分泌量比出发菌株Bs-916大大降低并导致其防效降低。【目的】为了确认影响该菌株防效降低的影响因子,对其表型和相关基因表达水平进行了研究。【方法】应用生孢培养基,通过芽胞形成能力评测方法比较该菌株和野生菌株Bs-916的芽胞形成能力;通过转化质粒的实验评测突变菌株M49和野生型Bs-916的
Construction and function analysis of Bac operon mutants of bio-control strain Bacillus subtilis Bs-916
生防菌Bs-916 合成脂肽类化合物Bac操纵子突变株构建及功能

Chuping Luo,Zhiyi Chen,Yongfeng Liu,Jie Zhang,Youzhou Liu,Xiaoyu Wang,Yafeng Nie,<br>罗楚平,陈志谊,,张杰,邮洲,王晓,聂亚
微生物学报 , 2009,
Abstract: 摘要:生防枯草芽孢杆菌Bs-916对水稻纹枯病有很好的防治效果。【目的】明确其合成脂肽类化合物操纵子Bac功能,为遗传改良提高Bs-916防效奠定基础。【方法】采用同源重组方法成功更换Bac内源启动子为组成性表达强启动子和插入失活Bac启动子,分别得到突变株BGG104和BGG105。突变株生物学活性测定结果表明:BGG104上清液相对Bs-916上清液对几种病原真菌毒力,血红细胞的溶血能力都显著提高;而BGG105则显著降低。采用6 mol/L盐酸沉淀及甲醇抽提方法从Bs-916和突变株培养液中制备脂肽
灌溉方式与施肥水平对超级稻光合生理的影响
,李伏生
中国生态农业学报 , 2013,
Abstract: 为研究不同施肥水平下节水灌溉方式对超级稻光合生理的影响,通过盆栽试验研究了3种施肥水平(不施肥、低肥和高肥)和3种灌溉方式[常规灌溉(FIR)、控制灌溉(CIR)和间歇灌溉(IIR)]对"中浙优1号"拔节期、抽穗期和乳熟期叶片净光合速率(Pn)、胞间CO2浓度(Ci)、光合光响应曲线和光合色素含量的影响,以及光合速率与光合色素的关系。结果表明,与FIR处理相比,CIR和IIR处理提高了3个生育期"中浙优1号"的Pn,而Ci提高不明显;分别使拔节期、抽穗期"中浙优1号"的光饱和点增加9.2%~36.8%和3个生育期表观量子效率增加6.7%~31.5%,但使拔节期、抽穗期和乳熟期光补偿点降低3.2%~12.8%。与FIR相比,CIR分别增加拔节期、抽穗期和乳熟期叶绿素a、叶绿素b、类胡萝卜素和总叶绿素含量19.1%~76.3%、44.5%~98.5%、31.5%~117.4%和45.4%~145.0%;IIR处理分别提高3个生育期类胡萝卜素和总叶绿素含量4.2%~45.8%和31.5%~117.4%。不同灌溉方式下,施肥处理"中浙优1号"光合生理指标和光合色素含量均高于不施肥处理,高肥处理又高于低肥处理。通过"中浙优1号"光合速率与光合色素含量的相关分析发现,其Pn与同期光合色素含量存在显著相关性,并受到生育时期的影响。因此,CIR和IIR处理能提高"中浙优1号"的光合能力,提高其对强光的光合能力和弱光条件下的适应性,提高了光饱和点,进而增加光能利用率,并提高了功能叶光合色素含量,有效改善其叶片光响应特征。同时,在节水灌溉条件下,在一定范围内增施肥料均能明显提高"中浙优1号"的光合机能。
Ge Pre-Amorphization Silicide Process for Fully-Depleted SOI CMOS Devices
Ge预非晶化硅化物工艺的研究

Sun Haifeng,Liu Xinyu,Hai Chaohe,Xu Qiuxia,Wu Dexin,<br>孙海,,海潮和,徐秋霞,吴德馨
半导体学报 , 2002,
Abstract: 对全耗尽 SOI CMOS技术中的 Ge预非晶化硅化物工艺进行了研究 .Ge的注入 ,使 Si非晶化 ,减小了硅化物的形成能量 .Ti硅化物在非晶层上形成 .与传统的 Ti硅化物相比 ,注 Ge硅化物工艺有两个明显的特点 :一是硅化物形成温度较低 ;二是硅化物厚度容易控制 .采用注 Ge硅化物工艺 ,使源漏薄层电阻约为 5 .2Ω /□ .经过工艺流片 ,获得了性能良好的器件和电路 ,其中 ,当工作电压为 5 V时 ,0 .8μm 10 1级环振电路延迟为 45 ps
Luminescence and Recombination Centers in ZnO/Si Films
硅基氧化锌薄膜中的发光和复合中心

Liu Cihui,Yao Ran,Su Jianfeng,Ma Zeyu,Fu Zhuxi,<br>磁辉,姚然,苏剑,马泽,付竹西
半导体学报 , 2007,
Abstract: 报道了用MOCVD方法制备的硅基ZnO薄膜中的中性施主-价带D0h发光.ZnO/p-Si结构经空气中700 ℃退火1h,然后进行X射线衍射(XRD)、光致发光(PL)谱和I-V特性测量.实验得到不同载气流量制备的样品都具有整流特性.深能级瞬态谱(DLTS)测量探测到各样品中存在两个施主深能级E1和E2.相应的室温PL谱测量显示样品近带边发射包含不同的发光线.利用高斯拟合方法,样品S2a的PL谱分解为三条发光线b,c和d,其中发光线b可归结为ZnO中的激子发射;DLTS测量得到的施主能级E1与发光线c和d的局域态电离能Ed相关,为D0h中心.此外,实验揭示E2能级的相对隙态密度与PL谱的发光强度成反比,表明深能级E2具有复合中心性质.
10Gbps Transimpedance Amplifier for Optoelectronic Receivers Based on InGaP/GaAs HBTs
基于InGaP/GaAsHBT的10Gbps跨阻放大器(英文)

Yuan Zhipeng,Sun Haifeng,Liu Xinyu,Wu Dexin,<br>袁志鹏,孙海,,吴德馨
半导体学报 , 2004,
Abstract: 采用InGaP/GaAsHBTs设计并实现了传输速率为10Gbps的跨阻放大器.在电路设计上采用两级放大器级联的形式以提高跨阻增益,在第一级采用了cascade结构,第二级采用了cherryhooper结构以提高电路的带宽和稳定性.测试结果表明,跨阻增益为40dB·Ω,3dB带宽为10GHz.
Research on clustering of natural scence images with texts based on random projection
基于随机投影的场景文本图像聚类方法研究

XU Fei,LIU Jia-feng,ZHANG Bo-yu,WU Rui,ZHAO Wei,<br>徐飞,,张博,吴锐,赵巍
计算机应用研究 , 2011,
Abstract: 图像中的文本字符存在于杂乱的背景之中,拍摄视角的不同使得文本具有较大的几何变形,再加上存在光照变化、字符颜色不统一等现象会导致背景分离和文本识别困难.为此提出一种基于图像文本区域的图像聚类方法.该方法首先对自然场景图像中已定位的文本区域提取局部特征描述,并使用随机投影方法将局部特征矢量集映射为固定维的特征向量,然后对包含图像文本区域的图像进行聚类.这种方法避免了由图像分割与字符识别带来的困难.实验结果表明,该方法可以对包含文字的自然场景图像有效地进行聚类,聚类的准确率能达到86.66%.
A Method of Image Compressing and Transmitting Based on Embedded Linux
一种嵌入式Linux环境下图像压缩及传输的实现

YANG Tian-Yi,LiU Yu,QU Jian-Feng,CHAI Yi,<br>杨天怡,,屈剑,柴毅
计算机科学 , 2006,
Abstract: In nowadays surveillance system,it's a great trend that to use low cost and general-purposed network cam- era as it's image input device.And this trend helps the traditional surveillance system to be more convenient and pow- erful.The system that we discusses in this thesis,gives a solution for industry clients,is based on the platform which embedded Linux and Samsung S3C2410.The thesis discusses and realizes the DCT image compressing,which diminish the data flow in the image transmitting.
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