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Complete genome sequence of Bacillus amyloliquefaciens YP6, a plant growth rhizobacterium efficiently degrading a wide range of organophosphorus pesticides

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Journal of Integrative Agriculture 2019年第11期18卷 2668-2672页

作者： MENG Di ZHAI Li-xin TIAN Qiao-peng GUAN Zheng-bing CAI Yu-jie LIAO Xiang-ru Key Laboratory of Industrial Biotechnology Ministry of Education School of Biotechnology Jiangnan University

Bacillus amyloliquefaciens YP6,a plant growth promoting rhizobacteria,is capable of efficiently degrading a wide range of organophosphorus pesticides(OPs).Here,we report the complete genome sequence of this bacterium with a genome size of 4009619 bp,4210 protein-coding genes and an average GC content of 45.9%.Based on the genome sequence,several genes previously described as being involved in solubilizing-phosphorus,OPs-degradation,indole-3-acetic acid(IAA)and siderophores synthesis.Interestingly,compared with the genomes of B.amyloliquefaciens species,strain YP6 had larger genome size and the most protein-coding genes.Moreover,the four categories of“cell envelope biogenesis,outer membrane(M),”“translation,ribosomal structure and biogenesis(J),”“transcription(K),”and“signal transduction mechanisms(T)”were fewer.These differences may be related to extensive environmental adaptability of the genus B.amyloliquefaciens.These results expand the application potential of strain YP6 for environmental bioremediation,provide gene resources involved in OPs degradation for biotechnology and gene engineering,and contribute to provide insights into the relationship between microorganism and living environment.

关键词： organophosphorus pesticides genome sequence plant growth promoting rhizobacteria Bacillus amyloliquefaciens

Solidification sequence and as-cast microstructure of a model Pb-Bi-Sn alloy with quasi-peritectic reaction

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China Foundry 2019年第6期16卷 399-405页

作者： Gang Liu Qian Yang Cao Wang Zhu-huan Yu Guo-jun Zhang School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China School of Materials Science and Engineering Xi’an University of Science and TechnologyXi’an710054China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

The Pb39 Bi25 Sn36 alloy was directionally solidified at varied withdrawal rates followed by quenching.From metallographic observation,composition analysis and differential scanning calorimetry(DSC)analysis,the solidification sequence of Pb39 Bi25 Sn36 alloy was characterized.The Sn-dendrite is observed as the primary phase during solidification,followed by theβ(Pb7 Bi3)/Sn divorced eutectic.At lower temperatures,theβ(Pb7 Bi3)/Sn binary eutectic is formed in the interdendritic region.However,the quasi-peritectic reaction[L+α-Pb→β(Pb7 Bi3)+Sn]does not occur as the prediction based on ternary phase diagram analysis,which can be attributed to the unequilibrium solidfication condition.Moreover,the as-cast microstructure is significantly refined with the increasing withdrawal rates.The quenched sample only exhibits the lamellar structure of Sn,β(Pb7 Bi3)and Bi phases.The results can provide instructions to optimize the as-cast microstructure of ternary alloys with quasi-peritectic reaction.

关键词： quasi-peritectic alloy directional solidification solidification sequence

Real-Time Update of sequence Placement Logic for High Arch Dams Based on Evidence Weight Discount

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Transactions of Tianjin University 2017年第3期23卷 267-276页

作者： Tao Guan Denghua Zhong Bingyu Ren State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

sequence placement logic plays a significant role in construction simulation of high arch dams and directly affects the simulation process and results.To establish a sequence logic for dam block placement,the construction scheme,real-time construction process,and random factors of the site all need to be considered in detail.There are few studies available currently that take all these factors into consideration.To address this problem,a real-time update of sequence placement logic for high arch dams based on evidence weight discount is proposed in this study.First,the subjective weight of the dam block sequence priority criteria is built using a consistent matrix method based on the construction scheme.Second,using evidence theory,dynamic objective weight of the priority criteria and basic probability assignment is built.Finally,using a weight self-adaptive adjustment method and comprehensive evidence discounting,the placing probabilities of different dam blocks are obtained.A case study indicates that this method can realize realtime update of sequence placement logic.

关键词： sequence placement logic Evidence theory Weight self-adaptive adjustment method Evidence weight discount Real-time update

Permian sequence stratigraphy of slope facies in southern Guizhou and chronostratigraphic correlation

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Science China Earth Sciences 2000年第1期43卷 63-76页

作者：史晓颖梅仕龙孙岩 China University of Geosciences Beijing 100083 China

The Permian in slope facies area of southern Guizhou consists of 16 third order sequences, which can be grouped as four sequence sets and further into two mesosequences. Most of them are delineated by conformable or submarine erosion surfaces, and well controlled by conodont and fusulinid zones. Four important sea-level falls are recognized in the area, which occur respectively at the basal Sweetognathodus white! zone, lower S.aff. hanzhongensis zone, middle Jinogondolella xuanhanensis zone and the basal Clarkina y/n/zone. Among the recognized transgression events, three are regarded as the most significant. They occur respectively at the basal Neogondolella exculptus zone, basal Jinogondolella nankingensis zone and the lower Clarkina postbitteri zone, and are all accompanied by faunal turnovers. The key surfaces in sequences can be used to fine-tune the boundaries of bio-chronozones, stages and series.

关键词： Permian sequence stratigraphy slope facies southern Guizhou correlation.

INVOLUTION NUMBER sequence AND DIMENSIONS OF THE COMPONENTS IN FIXED POINT SET OF AN INVOLUTION Ⅱ

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Science China Mathematics 1992年第7期35卷 819-825页

作者：吴振德杨华建刘宗泽 Department of Mathematics Hebei Normal University Shijiazhuang 050016 PRC Department of Mathematics South China Normal University Guangzhou 510631 PRC

By the application of the involution number sequence introduced in the previous paper~[1], we prove in this paper that the fixed point set of any smooth unfree involution on (S^1)~n must be constant-dimensional.

关键词： Wu class Stiefel-Whitney class involution number sequence Leray-Hirsch theorem.

A characterization for a graphic sequence to be potentially C_r-graphic

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Science China Mathematics 2010年第11期53卷 2893-2905页

作者： YIN JianHua Department of Mathematics, College of Information Science and Technology, Hainan University, Haikou 570228, China Department of Mathematics College of Information Science and Technology Hainan University Haikou China

Let r 3, n r and π = (d1, d2, . . . , dn) be a graphic sequence. If there exists a simple graph G on n vertices having degree sequence π such that G contains Cr (a cycle of length r) as a subgraph, then π is said to be potentially Cr-graphic. Li and Yin (2004) posed the following problem: characterize π = (d1, d2, . . . , dn) such that π is potentially Cr-graphic for r 3 and n r. Rao and Rao (1972) and Kundu (1973) answered this problem for the case of n = r. In this paper, this problem is solved completely.

关键词： graph cycle degree sequence

Enhanced Anti-Wear Property of Low Viscosity Engine Oil for sequence IVB Engine Test Meeting the GF-6 Specification

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China Petroleum Processing & Petrochemical Technology 2019年第2期21卷 95-102页

作者： Xie Xin Jia Qiulian Zhang Jianrong SINOPEC Research Institute of Petroleum Processing

The purpose of this research is to determine the anti-wear capability of new advanced low viscosity engine oil to meet the sequence IVB requirement of ILSAC GF-6 specification, which envisages that the first certification will be realized in 2020. The anti-wear performance of the aged candidate GF-6 engine oils was evaluated using the laboratory bench test rigs such as the Falex Pin & Vee Block test machine and the high frequency reciprocating rig (HFRR). The worn surfaces were analyzed by X-ray photoelectron spectroscopy (XPS). The remarkable anti-wear performance of the developed GF-6 engine oil was also confirmed in the sequence IVB test. The results indicate that by appropriately selecting and balancing the calcium detergent additives the wear loss of cam and tappet determined in the sequence IVB test at low temperature could be significantly reduced. The time for occurrence of the intersection of the base and acid values corresponds well with the increase of wear of cam tappet of the IVB engine test.

关键词： engine oil GF-6 sequence IVB anti-wear valvetrain wear

Timing sequence Changes of Landscape Plants in Shanghai Area,China

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Journal of Shanghai Jiaotong university(Science) 2011年第1期16卷 105-111页

作者：杨学军唐东芹邵芹英张建宇 Modern Agricultural Science and Engineering Institute Tongji University School of Agriculture and Biology Shanghai Jiaotong University Shanghai Simao Estate Company

Based on published reports and direct observation,the common resources of landscape plant species in the Shanghai area were identified and studied in terms of the landscape characteristics of timing sequence changes over a one year time period.The results showed that there were 199 common landscape plant species in Shanghai,distributed in 67 families and 129 genera.These plants were categorized by three ornamental characteristics:flowers,foliage and fruits.The species were thus further analyzed according to the time periods which these characteristics were present.The results showed that flower ornamental distributed throughout the year,particularly from April to June,and plant species with colorful foliage could be seen every month,and particularly in November and December.On the other hand,few plant species with fruit ornamentals were observed in Shanghai area.The diversity of landscape timing sequence changes of the 199 plant species under examination was then analyzed by using the Shannon-Weiner and Simpson index formulas.The results showed that the higher diversity was observed in January,February and from August to October,while the lowest diversity was recorded from March to July and during November and December.The diversity of landscape characteristics of these plants was ranked according to foliage,flowers and fruit.Using this method,one park and one plant community were selected to evaluate the advantages and disadvantages of their time-changing plant landscape,with the goal of assessing the validity of the chosen ranking method.These results in the present study would be helpful to evaluate the plant landscape in a specified space and further enrich the diversity of plant and landscape by a target-oriented way.

关键词： landscape plants timing sequence diversity Shannon-Weiner index Simpson index Shanghai

Using Walsh-m Composite sequence and LDPC-QPSK Joint Iteration to Reduce ISI in Long-range Underwater Acoustic Systems

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Journal of Harbin Institute of Technology(New Series) 2013年第1期20卷 87-92页

作者： Fang Fu Dan-Feng Zhao College of Information and Communication Engineering Harbin Engineering University

To reduce inter-symbol-interference (ISI) in underwater acoustic (UWA) communication systems, a method based on LDPC-QPSK joint iteration and Walsh-m composite sequence is proposed in this paper. The method is intended for use in long-range and low signal-to-noise ratio (SNR) UWA communications. At the transmitter, Walsh-m composite sequence is introduced to resist multipath effect. At the receiver, a soft-input soft-output (SISO) module is implemented in a joint iterative process between QPSK demodulator and LDPC decoder. This method is demonstrated in three types of UWA channel models: positive, negative and invariable sound velocity gradients channels. It is shown that through contrastive simulation experiments, this method is more efficient than conventional methods based on independent decoding and demodulation. After two rounds of joint iteration, the proposed method can obtain 2.5 dB over conventional method at BER of 10-5. Numerical results verify that the proposed method is a good candidate for long-range underwater acoustic communication systems.

关键词： underwater acoustic communication joint iterative LDPC decoding QPSK demodulation Walsh-m composite sequence