27 resultados para 33-317
em Chinese Academy of Sciences Institutional Repositories Grid Portal
Resumo:
<正> 我们考虑非定线性方程组:Ax=b。 定理1 线性迭代法x~(k+1)=Sx~k+d,k=1,2,…对任意初值x~0都收敛的充要条件是: (1) x=Sx+d有解。
Resumo:
介绍了一种基于3×3和2×2光纤耦合器构成的非平衡马赫-曾德尔干涉仪的波长解调方案。理论分析和数据对比表明,相对于由两个2×2光纤耦合器构成的马赫-曾德尔干涉仪,本干涉仪具有宽谱的灵敏度、能跟踪波长的变化方向和相位展开的优点,实验方案用于测量固定在悬臂梁上的传感光纤布拉格光栅(FBG)的峰值波长变化,获得了±1pm的静态波长解调精度,在10Hz处的动态分辨率为27nε/√Hz。相位展开算法使得应变测量范围达到了2014με,对应的相位变化为3.22π。
Resumo:
作者回顾了秋海棠属植物的发现、命名和引种栽培历史,概述了对该属的分类、形态、解剖、染色体研究取得的进展.结合查阅文献、标本和野外考察、栽培、实验观察,论述了秋海棠科的形态特征、秋海棠属中国种的分组、分布和生态习性、生物学特性、栽培繁殖技术和组织培养技术.强调了保护秋海棠属濒危物种的紧迫性,本论文描述了作者亲自采集或引种栽培的33种2亚种、57号中国原产秋海棠属植物的形态和解剖学特征,分析了结构与功能的关系和不同特征对分类与鉴定的价值,提出了中国产秋海棠属6个组和秋海棠科3个属的演化趋势及相应的形态与解剖学证据,就秋海棠科在分类系统中的位置进行了讨论.本文的主要观察结果和论点如下: 1.首次报道本属成熟根的结构:四原型或五原型,木质部由厚壁细胞和放射状排列的导管组成. 2.茎中维管束环状排列,维管束之间有较宽的束间区.直立茎和花序梗的束间形成层向内产生硬化和木化的薄壁组织,将维管束连成封闭的环,但在直立茎和花序梗的节附近以及根状茎中维管束和束间区硬化程度弱,不形成硬化的封闭环.硬化封闭环是和茎的机械支持功能相联系的,节附近硬化程度弱则为离层的形成做准备,有的种除了轴维管束之外还有髓维管束. 3.茎、叶柄和中脉维管束的数目和分布在不同部位可有或大或小的变化,但对种的鉴定仍有一定价值,重要的是要注意选取具有可比性的相同部位.木质部和韧皮部的比例有时也表现出明显的种间差异. 4.叶片气孔只见于下表面,首次发现内环为4个副卫细胞的螺旋型气孔(已有报道的有不等细胞型和内环为3个副卫细胞的螺旋型).在茎、叶柄和托叶背面气孔生于看上去类似皮孔而实际上由初生组织构成的特殊通气结构上.在本属植物叶片上表面的突出体和子房翅有排水器存在. 5.对各器官特别是叶片表面的毛状体、突出体进行了肉眼、放大镜和显微镜观察,描述了它们的形态和组织学特征,比较了一些种间毛状体组型的区别及鉴定价值. 6.植物体内含有草酸和草酸钙晶体,晶体以棱晶、沙晶和晶簇的形式存在于秋海棠属植物的大部分器官和组织中,在几个细胞相邻处聚集的球形晶簇只见于Sect.Coelocentrum和Sect.Diploclinium,可能表明二者有较密切的关系. 7.根据对子房的解剖研究并结合营养器官特征,认为原来划归Sect.Reichenheimia的B.wangii实际属于Sect. Diploclinium,确认原来没有子房形态描述的B. peltatifolia属于Sect.Diploclinium,B.villifolia属于Sect. Platycentrum。 8.首次较详细描述了花柱和子房中引导组织的分布和形状变化情况。 9.通过对子房结构和其中维管束数目与分布的观察,认为Sect. Platycentrum的2室子房由3个心皮组成,它可能是由3室子房进化而来的. 10.推测中国原产的本属各组的演化趋势如下: (Sect. Mezierea ) →Scct. Sphenanthera → Sect. Begonia → Sect. Reichenheimia ↘Sect. Coelocentrum →Sect. Diploclinium↘ Sect. Platycentrum 11.推测秋海棠科内的演化趋势可能是:Hillebrandia→Begonia→Symbegonia. 12.秋海棠科叶片具单生气孔的种多数只有单表皮,叶片具气孔组的种多数有复表皮.单生气孔和单表皮是较原始的性状,气孔组和复表皮是衍生性状.在10.所列的各组和11.所列的Hillebrandia中,这些性状的发生是和主要依据子房特征而提出的演化趋势基本一致的. 13.中国种的花粉和种子形态变化幅度较小,组间差异不明显.花粉和种子形态表明中国种总的进化程度在秋海棠属中偏低,但没有非洲种所显示的极端情形. 14.证实文献报道的种子萌发时种盖掀起、颈细胞沿胞间层裂开,这是减少种皮对萌发种胚阻力的高度适应机制. 15.作者赞同秋海棠科比四数木科进化程度高、两个科关系最为接近的看法,认为Melchior (1964)修订的Engler系统和Takhtajan(1987)的分类系统对秋海棠科位置的安排可能更接近于反映秋海棠科和其他科之间的系统关系.
Resumo:
本发明公开了一种基于3×3耦合器两路输出的波长解调系统及方法,系统包括:高通滤波模块,对接收自3×3耦合器的任意两路干涉条纹进行高通滤波,滤去直流项后得到两路输出信号;乘法交叉相减模块,对两路信号进行乘法交叉相减,得到包含信号的正弦项和余弦项;微分平方相加模块,对信号进行消去包含信号的正弦和余弦项,得到信号微分的平方项;开方判断正负模块,对信号微分的平方项进行开根号运算,然后再对得到的结果进行正负的判断,得到信号的微分项;中值滤波积分模块,对信号的微分项进行中值滤波,滤去坏点后再经过积分器积分,得到最后的解调结果。本发明具有精度高,动态范围大,成本低,算法简单,容易实现组网的优点。
Resumo:
国家863计划(2007AA03Z415)
Resumo:
研究了基于3×3耦合器的非平衡迈克耳孙干涉仪的相位特性。由光纤耦合器的散射矩阵理论,推导出了当3×3耦合器分光比不均匀时,干涉仪三路输出信号相位差的表达式。根据实际使用的3×3耦合器各通道的插入损耗,经计算与修正得到其散射矩阵,并求出干涉仪三路输出信号的相位差分别为120.21°、120.77°和119.02°,与理想值120°的偏差在1°以内。实验测得的干涉仪三路输出信号的相位差随时间随机变化,经分析是由光偏振态随机变化引起的。相位差与理想值120°的偏离均在1°以内,符合理论分析得到的结论。
Resumo:
采用3×3耦合器的光纤光栅激光传感系统(FBGLS)的波长解调结果依赖于3×3耦合器的物理特性,解调结果会因3×3耦合器三路输出的直流项、干涉条纹可见度和相位差参数的不稳定而发生一定程度的失真。理论推导给出了标定参数的方法并实现了计算机编程,能够在较大信号时实时给出标定结果,同时给出了相应的解调方案。计算机模拟发现采用上述方法消除了由3×3耦合器三路输出的参数不稳定带来的谐波,实验中解调结果的对比表明该方法带来一定程度的改善,和标准参考传感器测量结果有很高的相关性,此外基于该解调方案的光纤光栅激光传感系统具有较高的分辨率、动态范围和线性度。
Resumo:
Continuous wave operation of a semiconductor laser diode based on five stacks of InAs quantum dots (QDs) embedded within strained InGaAs quantum wells as an active region is demonstrated. At room temperature, 355-mW output power at ground state of 1.33-1.35 microns for a 20-micron ridge-waveguide laser without facet coating is achieved. By optimizing the molecular beam epitaxy (MBE) growth conditions, the QD density per layer is raised to 4*10^(10) cm^(-2). The laser keeps lasing at ground state until the temperature reaches 65 Celsius degree.
Resumo:
于2010-11-23批量导入
Resumo:
采用微波消解、电感耦合高频等离子体原子发射光谱(ICP-AES)的方法,对62份不同小麦品种(系)中锌、铁、铜、钙、钠和钾的含量进行了测定。同时利用红外线品质测定仪对主要品质指标粗蛋白、湿面筋、沉降值进行了测定。结果表明,不同小麦品种(系)中各种矿质元素的含量存在差异,2006年小麦品种中铁含量变幅为18.55-58.19 ug/g,平均为30.83ug/g ,最高与最低的相差39.64ug/g;锌含量变幅为5.70-25.80 ug/g,平均为15.13ug/g ,最高与最低相差20.10ug/g。2008年小麦品种(系)中铁含量变幅为16.68-52.25 ug/g,平均为30.10ug/g,最高与最低相差35.58ug/g;锌含量变幅为12.29-33.47 ug/g,平均为21.11ug/g,最高与最低相差21.18ug/g;钙含量变幅为167.53-348.80ug/g,平均为248.59ug/g,最高与最低相差192.59ug/g;铜含量变幅为2.32-5.83 ug/g,平均为2.98ug/g,最高与最低的相差3.61ug/g;钾含量变幅为1822.71-4414.91 ug/g,平均为2617.87ug/g,最高与最低的相差2634.72ug/g;钠含量变幅为10.25-39.82 ug/g,平均为23.05ug/g,最高与最低的相差29.57ug/g。 两年不同小麦品种(系)中矿质元素的含量分析结果表明:铁、铜、钙、钠和钾含量年际变化不明显,说明小麦对铁、铜、钙、钠和钾的吸收较稳定;锌含量变化较大,可能受环境的影响比较大。分析各矿质元素含量与粗蛋白、湿面筋、沉降值及元素之间的相关关系,结果表明,锌含量与粗蛋白含量呈极显著正相关关系,相关系数为0.317,与湿面筋含量之间呈显著正相关,相关系数达到0.246;铁含量与粗蛋白含量呈显著的正相关关系,相关系数是0.262;铜、钙、钠和钾含量与粗蛋白含量、湿面筋和沉降值之间存在正相关,但不显著,其中钠与沉降值之间为负相关。表明施锌或铁对提高小麦粗蛋白和湿面筋有显著效应,其余矿质元素有促进作用但不明显。 利用RAPD分子标记技术对川育23、41058、川育20及其父母本进行分析,力图从分子水平找到小麦矿质元素含量之间的差异性,琼脂糖电泳结果表明不同的小麦品种(系)间扩增出了差异条带。 以上研究结果,将对筛选“微量营养强化型”小麦新材料,选育“微量营养强化型”小麦新品种奠定基础。 62 different wheat cultivars was digested with HNO3 in a tightly closed vessel heated under micro-wave,then contents of zinc,iron,copper,calcium,sodium and potassium were determined by inductively coupled plasma-atomic emission spectroscopy(ICP-AES).The main indexes of wheat quality such as total protein、wet glu and sedimentation volume were detected by Infratec 1255 Food & Feed Analyzer at the same time.The obtained results showed that variation for all of the mineral elements concentrations among different cultivars were observed .In 2006, the amplitude variation of the iron content was 18.55-58.19 ug/g,the average value was 30.83ug/g,and 39.64ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 5.70-25.8 ug/g,the average value was 15.13ug/g,and 20.10ug/g between the highest-content cultivar and the lowest one.In 2008, the amplitude variation of the iron content was 16.68-52.25 ug/g,the average value was 30.10ug/g,and 35.58ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 12.29-33.47 ug/g,the average value was 21.11ug/g,and 21.18ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the calcium content was 167.53-348.80ug/g,the average value was 248.59ug/g,and 192.59ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the copper content was 2.32-5.83 ug/g,the average value was 2.98ug/g,and 3.61ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the potassium content was 1822.71-4414.91 ug/g,the average value was 2617.87ug/g,and 2634.72ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the sodium content was 10.25-39.82 ug/g,the average value was 23.05ug/g,and 29.57ug/g between the highest-content cultivar and the lowest one. Analysis was made on the annual variation of mineral elements content in different Wheat cultivars ,the result shows:there is no obvious difference of iron ,copper ,sodium、calcium and potassium concentrations in wheat cultivars, suggesting the absorption of the iron, copper, sodium、calcium and potassium by wheat are relatively steady ,but zinc concentrations change obviously ,maybe influenced heavily by environment . The correlation between mineral elements 、mineral elements and total protein、mineral elements and sedimentation volume as well as mineral elements and wet glut were analysed in this paper, the result showed that there was significant positive correlation between zinc content and total protein (the correlation coefficient is 0.317), positive correlation between zinc content and wet glu (the correlation coefficient is 0.246), positive correlation between iron content and total protein (the correlation coefficient is 0.262). there was positive but not obvious correlation between the contents of copper, calcium, sodium or potassium and total protein, wet glut or sedimentation volume,among which was negative correlation between sodium and sedimentation volume.It was indicated zinc or iron fertilization has prominent effects in improving the total protein in wheat, the rest mineral elements have Non- obvious facilitation. The study then forecasted the genetic difference of different wheat by the molecular marker of RAPD in order to find differences in molecular level. Chuanyu23、41058、chuanyu20 as well as their male and female parents were analysed by RAPD markers,Agarose gel electrophoresis of DNA revealed the appearance of differential bands . The above-mentioned results of this study establish the foundation to screening the new materials of wheat of " strengthening type of micro- nutrition ", and to breeding the new wheat cultivars of" strengthening type of micro- nutrition ".
Resumo:
在不同角度测得的 33 4MeV/u17N +9Be反应中 ,发射中子的能谱具有复杂的形式 ,而且随着角度的增大显示出有规律的变化 发射中子至少来源于靶弹核间的核子 -核子碰撞、17N的破裂反应以及熔合热核的统计蒸发三种不同起源 分析结果表明 :反应体系三种起源的发射中子截面分别为 4 4 9,0 4 4和 5 5b
Resumo:
利用SHACAL-2的一个17轮差分非线性区分器,结合被猜测子密钥空间分割的方法和快速傅立叶变换,提出了一种攻击33轮SHACAL-2的新方法.该方法攻击33轮SHACAL-2需要244的选择明文、2496.6的33轮SHACAL-2加密和2502次算术运算,攻击成功概率为99%.与已有的结果相比较,新攻击有效地提高了单密钥下SHACAL-2的攻击轮数.