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一种双“L”形探针馈电宽带微带天线
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作者 宋祖勋 韦杜娟 张朋 《遥测遥控》 2013年第6期22-27,32,共7页
提出一种S波段带状双"L"形探针馈电的宽带微带天线。提出的双"L"形探针采用倒置容性馈电结构,探针结构相同,水平臂均为带状,位置对称。通过基于左右手复合传输线理论的馈电网络向天线提供幅度相同、相位相差180... 提出一种S波段带状双"L"形探针馈电的宽带微带天线。提出的双"L"形探针采用倒置容性馈电结构,探针结构相同,水平臂均为带状,位置对称。通过基于左右手复合传输线理论的馈电网络向天线提供幅度相同、相位相差180°的激励信号。计算结果表明,设计的天线在S11<-15dB时,阻抗带宽可达到47.73%(1.80GHz^2.85GHz),E面主极化辐射方向图对称,H面交叉极化小于-40dB。 展开更多
关键词 宽带微带天线 双“l”形探针 ClRH-Tl 馈电网络
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双“L”形、小高宽比砖混结构房屋爆破拆除
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作者 汪龙 谢金晶 汪小艳 《重庆建筑》 2014年第10期40-43,共4页
对不规则、小高宽比砖混结构房屋爆破拆除时,爆破前应将其切割成独立结构,提高其高宽比,使其达到2以上;同时,确保各独立结构起爆间隔时间达到2s以上。通过上述技术措施,成功拆除了一栋双"L"形、小高宽比砖混结构的房屋,为类... 对不规则、小高宽比砖混结构房屋爆破拆除时,爆破前应将其切割成独立结构,提高其高宽比,使其达到2以上;同时,确保各独立结构起爆间隔时间达到2s以上。通过上述技术措施,成功拆除了一栋双"L"形、小高宽比砖混结构的房屋,为类似工程提供了施工经验。 展开更多
关键词 双“l” 小高宽比 砖混结构 爆破拆除
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自制“L”形双钢板治疗pilon骨折 被引量:1
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作者 靳昭国 周明哲 +1 位作者 高雪玲 高科 《中国矫形外科杂志》 CAS CSCD 2002年第3期308-309,共2页
目的 :介绍“L”形双钢板治疗pilon骨折的方法 ,疗效 ,优点及手术要点。方法 :对 8例 pilon骨折采用开放复位 ,解剖重建 ,“L”形双钢板分别固定胫腓骨下端。结果 :随访 6~ 36个月 ,根据Olerud评定标准 :优 4例 ,良 3例 ,优良率 87.5 ... 目的 :介绍“L”形双钢板治疗pilon骨折的方法 ,疗效 ,优点及手术要点。方法 :对 8例 pilon骨折采用开放复位 ,解剖重建 ,“L”形双钢板分别固定胫腓骨下端。结果 :随访 6~ 36个月 ,根据Olerud评定标准 :优 4例 ,良 3例 ,优良率 87.5 %。结论 :“L”形双钢板固定治疗 pilon骨折 ,创伤小 ,操作简单 ,易于恢复、维持胫腓骨长度、外踝外翻角 ,胫骨关节面的完整。固定坚强可靠 。 展开更多
关键词 PIlON骨折 “l”形钢板 内固定 治疗
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Evolution of Main Characteristics of the Registered Cotton Cultivars in National Cotton Regional Trials in Yangtze River Valley 被引量:1
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作者 许乃银 李健 《Agricultural Science & Technology》 CAS 2014年第6期964-969,共6页
[Objective] The aim of this study was to characterize the national regis- tered varieties selected from cotton regional trials in Yangtze River Valley (YaRV) in recent years. [Method] Cotton cultivar classification ... [Objective] The aim of this study was to characterize the national regis- tered varieties selected from cotton regional trials in Yangtze River Valley (YaRV) in recent years. [Method] Cotton cultivar classification and comprehensive evaluation index were set up based on national cotton registration standard. GGE biplot method was adopted to analyze the correlation of major breeding target characters of 53 national registered cotton varieties in cotton regional trials in YaRV during 1981-2012. According to the shift of check cultivars in cotton regional trials in the past, the cotton regional trial practice since 1981 was divided into five periods. The dynamic of cultivar type's proportion and the evaluation index scores was analyzed across the five periods. [Result] There existed intricate interrelationship among cotton breeding target traits, which constrained it necessary to construct indices for com- prehensive evaluation of cotton varieties. The dynamic of cultivar types in the five periods indicated that type II varieties emerged since Simian 3 period and then its proportion decreased gradually; type Ⅲ varieties maintained a certain proportion in each period and kept on the rise overall; type Ⅳvarieties occupied the majority pro- portion of registered cultivars before 1993, but a minor proportion since Simian 3 period. On the other side, the change trend of the evaluation index demonstrated that the varieties registered before 2003 did not pass the qualified line at present. The peak scores appeared in the varieties registered during 2004-2008. The scores of the varieties registered after 2009 were only slightly over the qualified line. [Conclusion] More attention should be paid to the improvement and evaluation of micronaire, so as to guide the simultaneous development of high yielding and fiber quality in cotton breeding and registration procedure in YaRV. 展开更多
关键词 Cotton (Gossypium hirsutum l.) GGE biplot Variety type classification The Yangtze River Valley (YaRV)
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Synthesis and Crystal Structure of an Infinite 1D Zigzag Chain Compound (dimbH^+)(ClO_4^-) and Its Comparison with (dimb)2H_2O (dimb = 1,3-Di(imidazol-1-ylmethyl)-5-methylbenzene)
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作者 YAOJing-Cai MAYong-Lin +1 位作者 HUANGWei GOUShao-Hua 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第4期439-443,共5页
A new imidazolium compound, C15H17N4ClO4, was prepared from a flexible bidentate ligand of 1,3-di(imidazol-1-ylmethyl)-5-methylbenzene, and characterized by X-ray analysis. It is of orthorhombic, space group Pnma with... A new imidazolium compound, C15H17N4ClO4, was prepared from a flexible bidentate ligand of 1,3-di(imidazol-1-ylmethyl)-5-methylbenzene, and characterized by X-ray analysis. It is of orthorhombic, space group Pnma with a = 8.182(2), b = 12.874(3), c = 15.611(4) ? V = 1644.4(7) 3, Dc = 1.425 g/cm3, Z = 4, Mr = 352.78, m(MoKa) = 0.944 mm-1, F(000) = 736, S = 1.036, the final R = 0.0521 and wR = 0.1187 for 1128 observed reflections (I > 2s(I)). An infinite one-dimensional zigzag chain is formed by NH…N hydrogen bonding interactions between the imidazolium salt cations. 展开更多
关键词 di(imidazol-1-ylmethyl)-5-methylbenzene imidazolium salt hydrogen bonding interactions zigzag chain crystal structure
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江南传统村镇民宿设计可持续性模式思考——“江村”民宿设计实践探寻 被引量:1
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作者 陈学筠 《建筑与文化》 2017年第6期236-237,共2页
江浙地区就"民宿经济"展开了富有成效的探索和实践,涌现出了一批成功的民宿模式,但各地区民宿发展的基础迥异,经济特点不同,因此,不同区域情境下的民宿建设有着不同的发展方式,在建筑设计层面伴随着发展方式的不同而带来了具... 江浙地区就"民宿经济"展开了富有成效的探索和实践,涌现出了一批成功的民宿模式,但各地区民宿发展的基础迥异,经济特点不同,因此,不同区域情境下的民宿建设有着不同的发展方式,在建筑设计层面伴随着发展方式的不同而带来了具体的设计模式。 展开更多
关键词 民俗经济 口型院落 文化情怀空间 双“l”
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Evaluation of the hepatoprotective and antioxidant activities of Rubus parvifolius L. 被引量:7
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作者 Jie GAO Cui-rong SUN +5 位作者 Jie-hong YANG Jian-mei SHI Yue-guang DU Yu-yan ZHANG Jin-hui LI Hai-tong WAN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2011年第2期135-142,共8页
The hepatoprotective and antioxidant activities of the n-butanol extract of Rubus parvifolius L. (RPL), a widely used medicinal plant, were evaluated. Results demonstrated that RPL extract possessed pronounced hepat... The hepatoprotective and antioxidant activities of the n-butanol extract of Rubus parvifolius L. (RPL), a widely used medicinal plant, were evaluated. Results demonstrated that RPL extract possessed pronounced hepatoprotective effects against carbon tetrachloride (CCI4)-induced hepatic injury in mice, which was at least partially attributed to its strong antioxidant capacity. Treatment with RPL extract markedly attenuated the increases in serum alanine ami- notransferase (ALT) and aspartate aminotransferase (AST) levels caused by CCI4 intoxication. It also significantly prevented the decrease in superoxide dismutase (SOD) activity and the increase in malondialdehyde (MDA) content of liver tissue. Meanwhile, histopathological changes of hepatic damage were also remarkably ameliorated. Phytochemical analysis based on high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) revealed the presence of various phenolic compounds, including caffeic acid conjugates, ellagic acid glycosides, and flavonol glycosides, which might be responsible for the hepatoprotective and antioxidant activities of RPL. 展开更多
关键词 Rubus parvifofius l. High-performance liquid chromatography/tandem mass spectrometry (HPlC-MS/MS) Hepatoprotective activity Antioxidant activity
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