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排序方式: 共有1449条查询结果,搜索用时 15 毫秒
941.
提出了光纤法布里珀罗(F-P)腔传感器的双通道双波长解调方法,并在此基础上建立了传感器的实验解调系统。理论分析与实验研究了双波长法解调光纤法布里珀罗腔传感器的基本原理,证明了双波长双通道解调法可以补偿传感器光网中和波长无关的变动引起的误差。根据已知的法布里珀罗腔传感器初始腔长和腔两端面反射率,从腔长变化的动态范围、线性、灵敏度等方面考虑,对工作波长以及线宽进行了优化设计。对双波长双通道解调系统进行了实验和数据分析,经最小二乘法拟合后的线性拟合度达到98.35%。实验结果表明:该方法可满足解调光纤法布里珀罗腔传感器在灵敏度、响应速度以及稳定度上的要求。 相似文献
942.
943.
以匈牙利佩奇大学中医孔子学院特色建设实践为例,介绍中医孔院在中医国际教育和文化学术交流等方面的功能和平台作用,以及实现可持续发展的模式探索.反思孔子学院在融入中医特色建设过程中所面临的问题和挑战,并对未来孔子学院“产学研为一体”发展模式的构建提出设想. 相似文献
944.
施彦 《福建工程学院学报》2012,(5):466-471
以林纾的第一部翻译作品,也是他的成名作《巴黎茶花女遗事》为专案,对比20世纪80年代北京外国文学出版社出版的王振孙译本和《茶花女》英文版,专门从词汇入手,说明旧派的林纾其实并不\"旧\",在林以古文笔调翻译的西方小说中,已经自觉不自觉地表现出了新时代的讯息。林纾在译文中使用甚至创造了\"新名词\",在计时方法上也表现了很强的时代感。不过这种欲新还旧的状态非林纾本人,而是时代赋予的,在那种更迭的时代里翻译者不可避免地要面对新旧取舍的困境。 相似文献
945.
The Ballad of the Sad Café is one of McCullers’masterpieces. By depicting the triangle love story among the main char?acters—Miss Amelia, hunchbacked Cousin Lymon and Marvin Macy, the novella reveals the incredible complexity of human na?ture. By analyzing the absurd town, Miss Amelia’s free choices and the hellish relationship between its main characters from the Existentialist perspective, the main propositions of Existentialism have also been vividly reflected and also help to reveal the philo?sophical and social realistic significances behind the novella. 相似文献
946.
流式细胞仪具有快速、定量,同时分析多种细胞属性的优势,已越来越广泛应用于皮肤T细胞淋巴瘤.流式细胞仪可通过T细胞表面抗原相应抗体和T细胞受体Vβ抗体分别检测肿瘤性T细胞的异常免疫表型及单克隆性,成为蕈样肉芽肿和Sézary综合征辅助诊断和治疗监测的重要工具,其在伴外周血受累的蕈样肉芽肿和Sézary综合征诊断和治疗监测乃至发病机制研究中的应用将会有更加广阔的前景. 相似文献
947.
Juan Violante-González;Scott Monks;Yesenia Gallegos-Navarro;Nataly G. Santos-Bustos;Princessa J. Villalba-Vasquez;Jesús G. Padilla-Serrato;Griselda Pulido-Flores 《Parasite (Paris, France)》2020,27(1)
Parasite communities in Caranx sexfasciatus were characterized and analyzed to determine any interannual variations in structure and/or species composition. In total,422 C. sexfasciatus were collected from Acapulco Bay,Mexico,between May 2016 and March 2019. Thirty-two taxa of metazoan parasites were identified: five Monogenea,thirteen Digenea,one Acanthocephala,one Cestoda,three Nematoda,seven Copepoda,and two Isopoda. Monogeneans were the most frequent and abundant parasite species in all sampling years. Parasite species richness at the component community level varied significantly from 8 (May 2016) to 25 (March 2019) and was similar to previous reports for other species of Carangidae. The component communities and infracommunities in C. sexfasciatus were characterized by low parasite species numbers,low diversity,and dominance of a single species (the monogenean Neomicrocotyle pacifica ). Parasite community structure and species composition varied between sampling years and climatic seasons. Seasonal or local fluctuations in some biotic and abiotic environmental factors probably explain these variations. 相似文献
948.
Lanlan YAN 《电子学报:英文版》2019,28(3):610-617
Aiming at the drawback that the shape of Bézier triangles is fixed with respect to the control points, some blending functions with parameter and with similar properties to the bivariate Bernstein polynomials are presented. Few literatures introduce how do the blending functions are derived. This paper aims at providing the general construction method of adjustable Bézier triangles in polynomial space. With the help of degree elevation technique and based on the idea that the adjustable surfaces are defined by the adjustable control points, the shape adjustable Bézier triangles are defined. The construction process of the blending functions is demonstrated in detail. 相似文献
949.
Anton V. Kolesnikov;Taniel Danelian;Maxime Gommeaux;Andrey V. Maslov;Dmitriy V. Grazhdankin 《Bulletin de la Société Géologique de France》2017,188(1-2)
In the course of studying modern halotolerant microbial mats in salterns near the village of Kervalet, western France, we observed fanning-out and curved series of macroscopic ridges on the surface of a newly formed biofilm. The structure resembles the late Ediacaran fossil Arumberia which is globally distributed in Australia, Avalonia, Baltica, Siberia and India, always confined to intertidal and delta-plain settings subject to periodic desiccation or fluctuating salinity. Although the origin of the structure observed in modern microbial mats remains enigmatic, wrinkled and rugose variants of microbial biofilms in general exhibit increased levels of resistance to several environmental stresses. By analogy, the fossil Arumberia could be interpreted as a microbial mat morphotype (the “Arumberia” morph) developed in response to environmental perturbations in terminal Ediacaran shallow marine basins. If environmental conditions are likely to be responsible for the formation of Arumberia , it is not that a specific biological community has survived since the Ediacaran – it is that the biological response of microbial communities that manifested itself quite commonly in certain terminal Ediacaran and early Cambrian environments can still be found (seemingly in much more restricted settings) today.https://doi.org/10.1051/bsgf/2017006 相似文献
950.
孟祥虹;王植;马信龙;杨建平;郭林 《中华小儿外科杂志》2020,41(04):378-382
Perthes病是一种原因不明的儿童特发性股骨头坏死,常发生于2~14岁男性患儿。大多数预后良好,但仍有部分患儿成年后可残留股骨头畸形而致患侧髋关节过早发生骨关节炎。因此,临床医生亟需早期评估患儿预后以采取有效治疗方法避免不良结局。本文回顾和总结了X线平片和磁共振成像检查对Perthes病预后评价的价值,为临床早期评价疾病预后提供影像学依据。 相似文献