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Super Performance InGaP/GaAs HBT with Novel Structure 被引量:6
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作者 白大夫 刘训春 +2 位作者 王润梅 袁志鹏 孙海锋 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第7期756-761,共6页
A kind of super performance InGaP/GaAs HBT with f T=108GHz and f max =140GHz is demonstrated.The excellent frequency performance results from the novel structure of the U shaped emitter,together with sel... A kind of super performance InGaP/GaAs HBT with f T=108GHz and f max =140GHz is demonstrated.The excellent frequency performance results from the novel structure of the U shaped emitter,together with self aligned emitter and LEU(lateral etched undercut) technologies.The HBT with the novel structure shows a distinguished performance with BV CEO up to 25V.And excellent performance of low V offset of 105mV and V knee of 0 50V is great favor of low power applications.The differences due to the different structure are also compared. 展开更多
关键词 heterojunction bipolar transistor u shaped emitter self aligned emitter thermal handling capacity
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Identification of Antarctic minke and killer whales with passive acoustic monitoring in Prydz Bay, Antarctica
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作者 Ying JIANG Lian-Gang LÜ +2 位作者 Zongwei LIU Chunmei YANG Jingsong GUO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第2期485-495,共11页
Although four species of odontocete and four species of baleen whale have been recorded in Prydz Bay,their vocalizations have been rarely investigated.Underwater vocalizations were recorded during March 2017 in Prydz ... Although four species of odontocete and four species of baleen whale have been recorded in Prydz Bay,their vocalizations have been rarely investigated.Underwater vocalizations were recorded during March 2017 in Prydz Bay,Antarctica.Bio-duck sounds,downsweeps,inverted“u”shape signals,whistles,pulsed sounds,and broadband clicks were recorded.Bio-duck sounds and downsweeps were associated with Antarctic minke whales(Balaenoptera bonaerensis)based on visual observations.Similarities between inverted“u”shape signals,biphonic calls,and clicks with vocalizations previously described for killer whales(Orcinus orca)lead us believe the presence of Antarctic killer whales.According to sound structures,signal characteristics,and recording location,Antarctic type C killer whales were the most probable candidates to produce these detected calls.These represent the fi rst detection of inverted“u”shape signals in Antarctic waters,and the fi rst report of Antarctic killer whale in Prydz Bay based on passive acoustic monitoring.The co-existence of Antarctic minke and killer whales may imply that minke whales can detect diff erences between the sounds of mammal-eating and fi sh-eating killer whales.Our descriptions of these underwater vocalizations contribute to the limited body of information regarding the distribution and acoustic behavior of cetaceans in Prydz Bay. 展开更多
关键词 passive acoustic monitoring inverted“ushaped signal killer whale Antarctic minke whales Prydz Bay type C
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Effect of indigenous fungi on ochratoxin A produced by two species of Penicillium
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作者 Koteswara R.Vankudoth Aruna Boda +1 位作者 Girisham Sivadevuni Madhusudhan R.Solipuram 《Animal Nutrition》 SCIE 2016年第3期225-228,共4页
Interaction between indigenous fungal strains in preventing ochratoxin A(OTA) production by Penicillium verrucosum and Penicillium nordicum was studied in 100 mL of Czapek yeast autolysate(CYA) medium in a 250-mL &quo... Interaction between indigenous fungal strains in preventing ochratoxin A(OTA) production by Penicillium verrucosum and Penicillium nordicum was studied in 100 mL of Czapek yeast autolysate(CYA) medium in a 250-mL "U" shaped culture vessel in one end for 3 days. At the end of incubation period, test fungi inoculated and incubated at 27 ± 2℃ for another 14 days to study the inhibition of OTA production was estimated by high performance liquid chromatography(HPLC). Total inhibition of OTA production was recorded with Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Aspergillus ustus, Fusarium culmorum, Fusarium graminarium, Fusarium proliferatum, Penicillium chrysogenum, Penicillium expansum and Trichoderma viridae. A significant correlation coefficient(r) on growth(0.493, P < 0.0003) and OTA production(0.785, P < 0.0001) was observed between the tested Penicillium species and other coexisting fungi. In conclusion, the present investigation revealed that those indigenous fungi are necessary to minimize potential losses to the poultry farmer and toxicological hazards to the consumer as biological control agent in different foods and feeds. 展开更多
关键词 Poultry feed Indigenous fungi OTA Interaction "u" shaped culture vessel HPLC
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必须防止外资拉大我国居民收入分配的差距 被引量:15
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作者 张昊光 姜秀兰 《财经科学》 CSSCI 北大核心 2004年第2期82-86,共5页
针对我国居民收入分配愈来愈不平衡 ,从经济全球化的角度 ,采用格兰杰因果分析法研究外商直接投资与我国城镇居民收入差距之间的关系 ,表明外商直接投资是我国城镇居民收入差距拉大的原因之一。
关键词 基尼系数(Gini coefficient) 外商直接投资(FDI) “倒置u形曲线”(Invened ushaped curve)
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