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Basal birds from China:a brief review 被引量:4
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作者 李东升 Corwin SULLIVAN +1 位作者 周忠和 张福成 《Chinese Birds》 2010年第2期83-96,共14页
We use the term 'basal birds' for a relatively small number of primitive fossil birds that fall outside the major clade Ornithothoraces,which includes both modern birds and enantiorni-thines. Eight genera and ... We use the term 'basal birds' for a relatively small number of primitive fossil birds that fall outside the major clade Ornithothoraces,which includes both modern birds and enantiorni-thines. Eight genera and twelve valid species have been reported from China in the last 15 years,whereas Archaeopteryx lithographica remains the only basal bird to have been described from non-Chinese specimens(although confuciusornithid material is apparently present in North Korea).Here we briefly review the Chinese basal birds and their anatomy,phylogeny and ecology.Chinese fossils have contributed extensively to scientific understanding of early avian evolution,demon-strating collectively that basal birds were generally relatively large and morphologically and eco-logically quite diverse.Although some significant uncertainties remain,particularly with respect to the relative phylogenetic positions of Jeholornis,Sapeornis and Zhongornis,an increasingly clear picture of the first stages of avian evolution is emerging from the Chinese fossil record. 展开更多
关键词 basal birds China ANATOMY PHYLOGENY ECOLOGY
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CMS Level—1 Regional Calorimeter Trigger System
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作者 P.Chumney S.Dasu 等 《International Conference on Computing in High Energy and Nuclear Physics》 2001年第1期632-635,共4页
The CMS regional calorimeter trigger system detects signatures of electrons/photons,taus,jets,and missing and total transverse energy in a deadtinmess pipelined architecture .This system receives 7000 calorimeter treg... The CMS regional calorimeter trigger system detects signatures of electrons/photons,taus,jets,and missing and total transverse energy in a deadtinmess pipelined architecture .This system receives 7000 calorimeter tregger tower energies on 1.2 Gband digital copper cable serial links and processes them in a low-latency pipelined design using custom-built electronics.At the heart of the system is the Receiver Card which uses the new generation of gigabit ethernet receiver chips on a mezzanine card to convert serial data to parallel data before transmission on a 160 MHz backplane for further processing by cards that sum energies and identify electrons and jets.We describe the algorithms and hardware implementation,and summarize the simulation results that show that this system is capable of handling the rate requirements while triggering on physics signals with high efficiency. 展开更多
关键词 CMS实验 热量计 解发系统
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Existence results for a class of parabolic evolution equations in Banach spaces
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作者 王静 薛星美 《Journal of Southeast University(English Edition)》 EI CAS 2003年第2期182-187,共6页
We discuss the existence results of the parabolic evolution equation d(x(t)+g(t,x(t)))/dt+A(t)x(t)=f(t,x(t)) in Banach spaces, where A(t) generates an evolution system and functions f,g are continuous. We get the theo... We discuss the existence results of the parabolic evolution equation d(x(t)+g(t,x(t)))/dt+A(t)x(t)=f(t,x(t)) in Banach spaces, where A(t) generates an evolution system and functions f,g are continuous. We get the theorem of existence of a mild solution, the theorem of existence and uniqueness of a mild solution and the theorem of existence and uniqueness of an S-classical (semi-classical) solution. We extend the cases when g(t)=0 or A(t)=A. 展开更多
关键词 evolution system analytic semigroup mild solution semi-classical solution classical solution
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A brief review on the strategy for selection of orthology prediction methods in phylogenomic studies
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作者 吴昊阳 刘阳 +1 位作者 谢强 卜文俊 《Entomotaxonomia》 CSCD 北大核心 2012年第2期81-88,共8页
With the development and decreasing cost of sequencing techniques, it is possible for scientists to conduct deeper research in phylogenomics. During the procedure of phylogenomic analysis, the mostimportant and vitale... With the development and decreasing cost of sequencing techniques, it is possible for scientists to conduct deeper research in phylogenomics. During the procedure of phylogenomic analysis, the mostimportant and vitalest step is orthology prediction, for that the prerequisite to phylogenetic reconstruction is that the genes being compared are orthologous. Here we briefly review the related concept of orthology anddifferent methods for orthology prediction. We also provide recommendations to give some advice for better selection of orthology prediction methods. 展开更多
关键词 orthologous genes automatic tools tree-reconciliation phylogenetic reconstruction evolutionarystudy
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Isolation and Characterization of a Methomyl-Degrading Paracoccus sp.mdw-1 被引量:2
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作者 XU Jing-Liang WU Jun +5 位作者 WANG Zhi-Chun WANG Kun LI Meng-Ying JIANG Jian-Dong HE Jian LI Shun-Peng 《Pedosphere》 SCIE CAS CSCD 2009年第2期238-243,共6页
Methomyl, an extremely toxic pesticide, is widely used in agriculture. A strain named mdw-1 capable of degrading methomyl rapidly was successfully isolated from activated sludge in this study. It could utilize methomy... Methomyl, an extremely toxic pesticide, is widely used in agriculture. A strain named mdw-1 capable of degrading methomyl rapidly was successfully isolated from activated sludge in this study. It could utilize methomyl as the sole carbon or nitrogen source. The optimal temperature and medium pH for its growth and methomyl biodegradation were 30℃ and 7.0, respectively. It was identified as a Paracoccus sp. according to its morphological features, physiological and biochemical characteristics, and phylogenetic analysis based on the sequence of 16S rDNA. Gas chromatography-mass spectrometry (GC-MS) analysis showed that methomyl could be completely transformed to S-methyl-N-hydroxythioacetamidate in 10 h of incubation with the isolate mdw-1. 展开更多
关键词 methomyl degradation Paracoccus sp. S-methyl-N-hydroxythioacetamidate 16S rDNA strain mdw-1
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Dependency of Electrical Demand of Bangladesh Power System on the Weather of the Country
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作者 Nahid-Al-Masood Md. Quamrul Ahsan 《Journal of Energy and Power Engineering》 2012年第6期960-964,共5页
The variation of electrical demand above its base value is its common characteristic. The weather dependent variation of demand, especially where the weather is severe in nature, requires a significant reserve margin ... The variation of electrical demand above its base value is its common characteristic. The weather dependent variation of demand, especially where the weather is severe in nature, requires a significant reserve margin of the generation system. The evaluation of the weather dependent component of the electric demand is the basic tool for the planning of the reserve margin. This paper evaluates the weather dependent portion of the load of BPS (Bangladesh power system). The evaluation of the weather dependent portion of the demand is based on the EMD (empirical mode decomposition) technique. 展开更多
关键词 Weather sensitive component of load reserve margin load forecasting empirical mode decomposition temperature-humidity index generation capacity.
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Intelligent decoupling PID control for the forced-circulation evaporation system
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作者 王永刚 庞新富 +3 位作者 朴在林 方晶晶 付俊 柴天佑 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期2075-2086,共12页
The control objective of the forced-circulation evaporation process of alumina production is not only to avoid large fluctuations of the level, but also to ensure the product density to track its setpoint quickly. Due... The control objective of the forced-circulation evaporation process of alumina production is not only to avoid large fluctuations of the level, but also to ensure the product density to track its setpoint quickly. Due to the existence of strong coupling between the level loop and the product density loop, and high nonlinearities in the process, the conventional control strategy cannot achieve satisfactory control performance, and thus the production demand cannot be met. In this paper, an intelligent decoupling PID controller including conventional PID controllers, a decoupling compensator and a neural feedforward compensator is proposed. The parameters of such controller are determined by generalized predictive control law. Real-time experiment results show that the proposed method can decouple the loops effectively and thus improve the evaporation efficiency. 展开更多
关键词 Forced-circulation system Decoupling Neural networks Nonlinear system
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EXISTENCE AND UNIQUENESS OF STRONG PERIODIC SOLUTION OF THE EVOLUTION SYSTEM DESCRIBING GEOPHYSICAL FLOW-PART I: IN BOUNDED DOMAINS 被引量:1
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作者 ZHAO CHUNSHAN, LI KAITAI School of Science, Xi’an Jiaotong University, Xi’an 710049, China. 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2001年第3期385-396,共12页
The existence and uniqueness of a strong periodic solution of the evolution system describing geophysical flow in bounded domains of RN (N = 3, 4) are proven if external forces are periodic in time and sufficiently sm... The existence and uniqueness of a strong periodic solution of the evolution system describing geophysical flow in bounded domains of RN (N = 3, 4) are proven if external forces are periodic in time and sufficiently small. 展开更多
关键词 Existence and uniqueness Periodic solution Evolution system Geophysical flow
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Phosphate Solubilizing Ability and Phylogenetic Diversity of Bacteria from P-Rich Soils Around Dianchi Lake Drainage Area of China 被引量:15
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作者 YANG Pei-Xiang MA Li +7 位作者 CHEN Ming-Hui XI Jia-Qin HE Feng DUAN Chang-Qun MO Ming-He FANG Dun-Huang DUAN Yan-Qing YANG Fa-Xiang 《Pedosphere》 SCIE CAS CSCD 2012年第5期707-716,共10页
The phylogenetic diversity of phosphate solubilizing bacteria (PSB) distributed in P-rich soils in the Dianchi Lake drainage area of China was characterized, and the tricalcium phosphate (TCP) solubilizing activit... The phylogenetic diversity of phosphate solubilizing bacteria (PSB) distributed in P-rich soils in the Dianchi Lake drainage area of China was characterized, and the tricalcium phosphate (TCP) solubilizing activities of isolated PSB were determined. Among 1 328 bacteria isolated from 100 P-rich soil samples, 377 isolates (28.39% of the total) that exhibited TCP solubilization activity were taken as PSB. These PSB showed different abilities to solubilize TCP, with the concentrations of solubilized P in bacterial cultures varying from 33.48 to 69.63 mg L^(-1). A total of 123 PSB isolates, with relatively high TCP solubilization activity (〉 54.00 mg L^(-1)), were submitted for restriction fragment length polymorphism (RFLP) analysis, which revealed 32 unique RFLP patterns. Based on these patterns, 62 representative isolates, one to three from each RFLP pattern, were selected for 16S rRNA sequencing. Phylogenetic analysis placed the 123 PSB into three bacterial phyla, namely Proteobacteria, Aetinobacteria and Firmicutes. Members of Proteobacteria were the dominant PSB, where 107 isolates represented by 26 RFLP patterns were associated with the genera of Burkholderia, Pseudomonas, Acinetobacter, Enterobacter, Pantoea, Serratia, Klebsiella, Leclercia, Raoultella and Cedeeea. Firmicutes were the subdominant group, in which 13 isolates were affiliated with the genera of Bacillus and Brevibacterium. The remaining 3 isolates were identified as three species of the genus Arthrobacter. This research extends the knowledge on PSB in P-rich soils and broadens the spectrum of PSB for the development of environmentally friendly biophosphate fertilizers. 展开更多
关键词 phosphate solubilizing bacteria phylogenetic analysis P mine area restriction fragment length polymorphism analysis tricalcium phosphate solubilization activity
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