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基于投影熵特征的图像识别算法
,张科
计算机应用 , 2013,
Abstract: ?原始定义下的投影熵特征对于图像信息利用不够充分,而且对图像缩放变换不具有不变性,针对这两方面的不足,给出了扩展规范化投影熵特征的定义,并将规范化后图像的局部投影熵特征向量用于图像识别;在进行图像识别时,利用期望最大化(em)算法得到训练集图像局部投影熵特征的混合高斯概率分布模型,求取目标图像的相应特征到各个混合高斯函数的mahalanobis距离,根据距离判别法原理得到目标图像所属类别。实验采用哥伦比亚大学计算机视觉数据库中的图像对算法进行验证,结果表明该算法具有较好的识别效果和良好的并行运算特性
副产蒸汽氯化氢合成炉的模拟计算
The Simulation of Byproduct Steam Hydrogen Chloride Synthesis Furnace
 [PDF]

陈珊,, 方元, 魏顺安
Hans Journal of Chemical Engineering and Technology (HJCET) , 2012, DOI: 10.12677/hjcet.2012.21001
Abstract: 在氢气和氯气燃烧合成氯化氢的工业过程中,充分利用燃烧热是氯化氢合成炉设计和操作的长期目标。本文通过建立炉内反应及传热模型,采用微元段积分方法对副产蒸汽氯化氢合成炉进行模拟计算,计算结果与实际工况相符。计算结果表明:在整个传热过程中,辐射传热占主导地位,辐射传热量约是对流传热量的9倍;副产蒸汽移走了大部分反应热,能量利用率达到69.58%;蒸汽发生系统的有效能损失较大,副产蒸汽有效能为总有效能的37.71%。
Hydrogen chlorine (HCl) is synthesized by hydrogen and chlorine in the industry. Making full use of the reaction heat is our long-term goal in the design and operation process of HCl synthesis furnace. The model of reaction and heat transmission in the furnace is established on the byproduct steam HCl synthesis furnace. The simulation calculation is conducted by the method of infinitesimal section integral and the results are according with actual wo- rking conditions. The results show that: the radiation heat transfer is predominant in the whole heat transfer process and its heat transfer quantity is 9 times higher than convective heat transfer; Most of reaction heat is taken away by by- product steam and the ratio of energy utilization is up to 69.58%; The major loss of effective energy is in the generation system of stream and the effective energy of byproduct steam is only 37.71% of the whole effective energy.
西安交通大学机构知识库数据共享集成研究与实践
魏青山,张雪蕾,,
图书情报工作 , 2014,
Abstract: ?在建设西安交通大学机构知识库过程中,充分考虑学校现有不同信息平台及相关数据库平台的数据共享集成和再利用问题,重点研究机构库与统一身份认证系统的集成、与教师个人主页系统的集成、与学者库的集成、与wos平台的数据共享集成的解决方案及其相关关键技术的实现,包括机构库接口配置,并在实践中得到验证。这一研究与实践,不仅突破机构库信息孤岛的瓶颈,而且使得机构库的数据能为学校相关信息平台所共享,从而为学校教学和科研提供数据支撑及科研成果管理的拓展应用奠定基础。
甘蓝型油菜种子抗营养物质的研究
Study on Anti-Nutritional Compounds in Seeds of Brassica napus
 [PDF]

彦林, 高亚, 孔月琴, 王幼平
Botanical Research (BR) , 2013, DOI: 10.12677/BR.2013.22010
Abstract:

甘蓝型油菜是重要的油料作物,不仅可生产食用油,而且其饼粕富含蛋白质,可作为动物饲料。油菜种子中因含有大量抗营养物质,如多酚化合物、木质素和纤维素等,其中多酚物质主要包括单宁、原花色素、类黄酮、羟基苯丙烯酸的衍生物和芥子油苷等,这些物质会严重影响菜籽油的品质和饲料的营养价值。本文主要介绍这些抗营养物质的种类、分离和测定方法,为油菜品质育种和改良提供参考。
Rapeseed (Brassica napus L.) is the second largest oil crop in the world. And rapeseed meal, the by-product after oil processing, has been considered as a good source for protein and animal forage, which makes rapeseed an useful economic crop. However, the utilization of rapeseed is still limited to the existance of abundant anti-nutritional factors including phenolic compounds, lignin and fibre. Hence, improving the quality of rapeseed with reduced anti-nutritional factors is becoming the primary mission for rapeseed breeders. The phenolic compounds of rapeseed mainly include plant tannins, proanthocyanidins, flavonoids, hydroxycinnamic acid derivatives and glucosinolate. Since proanthocyanidins (PAs) is relevant to the formation of pigments in seed coat, many studies focused on discovering biosynthetic pathway and better quantification of PAs. At the same time, the group of anti-nutritional factors is interrelated to one another, which need to be deeply clarified by further studies in the future, including their synthetic precursors, biosynthetic pathway and molecular mechanisms.

甘蓝型油菜未成熟种子多酚的研究
Analysis of Phenolic Compounds in Developing Seeds of Brassica napus
 [PDF]

彦林, 高亚, 孔月琴, 蒋金金, 王幼平
Botanical Research (BR) , 2013, DOI: 10.12677/BR.2013.23014
Abstract:

甘蓝型油菜种子含有大量的多酚物质,主要是羟基苯丙烯酸衍生物、原花色素和类黄酮衍生物,不同研究者对多酚物质的研究方法各异。本文使用化学分析和HPLC-ESI/MS2分析,首先研究了不同溶液在不同温度下对油菜籽多酚物质萃取效率的影响,发现80%的丙酮水溶液在室温条件下对油菜籽多酚的萃取效率最高。进一步对未成熟种子种皮和胚多酚物质进行研究,发现总酚和总类黄酮含量种皮明显高于胚。多酚物质中,种皮类黄酮和原花色素的含量要高于胚,但羟基苯丙烯酸衍生物的含量要低于胚。芥子碱是油菜籽中含量最丰富的多酚物质,主要存在于胚当中。而表儿茶素是含量最丰富的类黄酮物质,主要存在于种皮当中。
Phenolics are abundant in seeds of Brassica napus, mainly including hydroxycinnamic acid derivatives, proanthocyanidins (PAs) and flavonoid derivatives. Different research methods have been reported by researchers. In this research, both chemical analysis and HPLC-ESI/MS2 analysis were conducted to compare the different compositions of soluble phenolics in embryo and seed coat of B. napus. The extraction parameters were also optimized by comparing single factors like extraction temperature and solvent. And the results showed that room temperature and solvent of 80% acetone yielded the maximum phenolics. Further comparison showed that total phenolics and flavonoids in seed coat were much higher than in embryo of immature seeds. Among the identified phenolics, flavonoid and proanthocyanidin in seed coat were higher than in embryo, whereas derivatives of hydroxyl-cinnamic acid were lower accumulated in seed coat than embryo. Sinapine, as the most abundant phenolics, was mainly existed in embryo. And epicatechin was abundant in seed coat, which was well known as the most abundant flavonoids.

珠江三角洲东部常平地区景观异质性研究
曾辉,,郭庆华
地理学报 , 1999, DOI: 10.11821/xb199903008
Abstract: 本文以1988年~1996年6个时段景观遥感类型图为主要信息源,利用信息熵法和空隙度指数法对珠江三角洲东部常平地区的景观异质性进行了研究。重点探讨了景观组分的空间分布差异和异质性动态变化情况。结果显示,开发区主要呈宏观异质性分布,果园、农田和林地呈微观异质性分布,城镇和水体的异质性分布特征均出现显着变化。
干道信号交叉口群协调控制系统中的影响因素
,春福,赵熠
哈尔滨工业大学学报 , 2011, DOI: 10.11918/j.issn.0367-6234.2011.06.023
Abstract: 为了改进现有干道协调控制优化算法,给出基于相位相序调整的绿波带宽优化模型,讨论了影响干道系统协调控制优化的3个重要因素,为验证优化模型的效果,设计了干道协调控制优化的计算机仿真程序,并在9种模拟干道系统的等间距交叉口和不等间距交叉口情况下,共生成了90000组仿真场景进行对比分析.结果表明:"主向左转提前"和"次向左转提前"2种相序在干道系统中的使用比例比"左转提前"和"左转滞后"普遍高5%;另外,通过分析交叉口间距对干道协调控制优化的影响,得出等间距交叉口在干道协调控制优化中并没有明显优势,不等间距交叉口的干道系统反而更容易得到优化方案;此外,交叉口数量对干道系统的绿波利用率影响也比较明显,当干道系统中交叉口数量超过16时,干道系统基本无法获得双向绿波带.
荧光假单胞菌天冬氨酸转氨酶的基因克隆及其在大肠杆菌中的表达
,王虹,李荣贵
中国生物工程杂志 , 2009,
Abstract: 采用克隆基因测序技术,从荧光假单胞菌gcm5-1a基因组文库中筛选到了天冬氨酸转氨酶的编码基因aspc。通过聚合酶链式反应(pcr)扩增目的基因,插入pet-15b构建重组表达质粒pet-15baat,转化e.colibl21(de3),iptg诱导天冬氨酸转氨酶在大肠杆菌中高效表达,利用亲和层析法初步分离纯化了重组蛋白。生物活性分析表明,纯化的重组天门冬氨酸转氨酶具有氨基转移活性。
砂土液化及液化后流动特性试验研究
陈育民,刘汉龙,国建,
岩石工程学报 , 2009,
Abstract: 根据流体力学中的绕球定常黏性流动理论,在振动台试验的基础上,设计了一套砂土液化及液化后流动特性的试验装置。在振动台模型箱的砂土中埋入可以水平滑动的钢球,当砂土发生液化时使钢球发生水平运动,通过测量钢球所受的阻力来反算液化及液化后砂土的表观动力黏度,进而研究液化及液化后砂土的流动特性。试验中考虑了砂土的初始相对密度、钢球的运动速率、液化后砂土的超孔压比等因素的影响。试验结果表明,液化及液化后状态下砂土的表观动力黏度随着应变率的增大而减小,液化砂土呈现出剪切稀化的非牛顿流体特性。随着液化后超孔压比的降低,表观动力黏度也逐渐增大,通常随着应变率的增大,表观动力黏度–超孔压比曲线逐渐变缓。
锥扫LFMCW雷达信号处理方法的研究
赵宏图,郭昕,,李晓良
北京理工大学学报 , 2006,
Abstract: 基于线性调频连续波及圆锥扫描理论,研究锥扫线性调频连续波雷达信号处理方法.针对回波信号的特点,将频域法运用于锥扫线性调频连续波信号.论证了该信号可以在距离高分辨率的基础上进行有效测角,分析了信号处理时频谱泄漏对系统造成的影响,并对泄漏进行了补偿.计算机仿真结果表明,该方法可应用于跟踪雷达的信号处理中.
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