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Advances in Atmospheric Sciences 2016年第2期33卷 259-268页

作者： lei song Yinan WANG Institute of Atmospheric Physics Chinese Academy of Sciences

The radiation budget at the top of the atmosphere plays a critical role in climate research. Compared to the broadband flux, the spectrally resolved outgoing longwave radiation or flux （OLR）, with rich atmospheric information in different bands, has obvious advantages in the evaluation of GCMs. Unlike methods that need auxiliary measurements and information, here we take atmospheric infrared sounder （AIRS） observations as an example to build a self-consistent algorithm by an angular distribution model （ADM）, based solely on radiance observations, to estimate clear-sky spectrally resolved fluxes over tropical oceans. As the key step for such an ADM, scene type estimations are obtained from radiance and brightness temperature in selected AIRS channels. Then, broadband OLR as well as synthetic spectral fluxes are derived by the spectral ADM and validated using both synthetic spectra and CERES （Clouds and the Earth＇s Radiant Energy System） observations. In most situations, the mean OLR differences between the spectral ADM products and the CERES observations are within -4-2 W m-2, which is less than 1% of the typical mean clear-sky OLR over tropical oceans. The whole algorithm described in this study can be easily extended to other similar hyperspectral radiance measurements.

关键词： hyperspectral radiance spectral angular distribution model scene type atmospheric infrared sounder

Research on parafoil stability using a rapid estimate model

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Chinese Journal of Aeronautics 2017年第5期30卷 1670-1680页

作者： Hua YANG lei song Weifang CHEN School of Aeronautics and Astronautics Zhejiang University School of Aeronautic Science and Engineering Beihang University

With the consideration of rotation between canopy and payload of parafoil system, a four-degree-of-freedom（4-DOF） longitudinal static model was used to solve parafoil state variables in straight steady flight. The aerodynamic solution of parafoil system was a combination of vortex lattice method（VLM） and engineering estimation method. Based on small disturbance assumption,a 6-DOF linear model that considers canopy additional mass was established with benchmark state calculated by 4-DOF static model. Modal analysis of a dynamic model was used to calculate the stability parameters. This method, which is based on a small disturbance linear model and modal analysis, is high-efficiency to the study of parafoil stability. It is well suited for rapid stability analysis in the preliminary stage of parafoil design. Using this method, this paper shows that longitudinal and lateral stability will both decrease when a steady climbing angle increases. This explains the wavy track of the parafoil observed during climbing.

关键词： Dynamic model Motion mode Parafoil Small-disturbance theory Stability

Modular synthesis of β-amino acids from alkenes,amines,and CO_(2) via photoredox/copper dual catalysis

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Science China Chemistry 2024年第6期67卷 1756-1757页

作者： lei song Jie Wu Department of Chemistry National University of SingaporeSingapore117543Singapore National University of Singapore(Chongqing)Research Institute Chongqing401120China

The conversion of industrial waste into value-added chemicals represents a compelling approach to bolster sustainability *** the primary components of greenhouse gases,carbon dioxide(CO_(2))stands as an ideal C_(1) so... 详细信息

关键词： catalysis synthesis amines

Quasi-Maximum Likelihood Estimators in Generalized Linear Models with Autoregressive Processes

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Acta Mathematica Sinica,English Series 2014年第12期30卷 2085-2102页

作者： Hong Chang HU lei song School of Mathematics and Statistics Hubei Normal University Educational Research Institute

The paper studies a generalized linear model（GLM）yt = h（xt^T β）＋ εt,t = l,2,...,n,where ε1 = η1,ε1 =ρεt ＋ηt,t = 2,3,...;n,h is a continuous differentiable function,ηt＇s are independent and identically distributed random errors with zero mean and finite variance σ^***,the quasi-maximum likelihood（QML） estimators of β,p and σ^2 are ***,under mild conditions,the asymptotic properties（including the existence,weak consistency and asymptotic distribution） of the QML estimators are ***,the validity of method is illuminated by a simulation example.

关键词： Generalized linear model quasi-maximum likelihood estimator autoregressive processes weak consistency asymptotic distribution

Synthesis of cyclicβ-silylenones via oxidative rearrangement of tertiaryα-hydroxy allylsilanes with PCC

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Chinese Chemical Letters 2011年第3期22卷 306-309页

作者： Xia Wu Jian lei Zhen lei song Key Laboratory of Drug-Targeting of Education Ministry and Department of Medicinal Chemistry West China School of Pharmacy Sichuan University Chengdu 610041 China

An oxidative rearrangement of cyclic tertiary a-hydroxy allylsilanes has been carried out in refluxing ClCH_2CH_2Cl with pyridinium chlorochromate（PCC）.The reaction provides a convenient method to synthesize cyclic... 详细信息

关键词： Pyridinium chlorochromate Oxidative rearrangement Cyclicβ-silylenones

Innovation for ascertaining genomic islands in PAO1 and PA14 of Pseudomonas aeruginosa

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Chinese Science Bulletin 2009年第21期54卷 3991-3999页

作者： song lei ZHANG XueHong Key Laboratory of Microbial Metabolism Ministry of Education School of Life Sciences and Biotechnology Shanghai Jiao Tong University Shanghai 200240 China College of Life and Environment Science Shanghai Normal University Shanghai 200234 China

Based on three distinct traits of genomic islands, a novel approach was developed to search for and determine genomic islands in special strains. Two genomic islands in Pseudomonas aeruginosa PAO1 and 7 genomic islands in Pseudomonas aeruginosa PA14 were defined with this method. Among the 9 genomic islands, 4 islands had been characterized before, while the other 5 islands were initially determined. The insert sites of 6 genomic islands are tRNA sequences, direct repeats of PA14GI-3 are relative to tRNALeu, and direct repeats of PA14GI-2 are at the 3′ end of bifunctional GMP synthase/ glutamine amidotransferase. Only direct repeats of PA14GI-4 are not clear. Among the 5 newly-found genomic islands, it was supposed that PA14GI-2 is a genomic island related to Hg2+ uptake, PA14GI-3 is a secretory activity genomic island, PA14GI-6 is a pathogenicity island, and functions of PA14GI-1 and PA14GI-5 are not clear. Finally, the tyrosine type integrases in PAO1GI-1, PA14GI-5 and PA14GI-7 were analyzed, and their binding and restriction sites were predicted.

关键词：基因组铜绿假单胞菌岛屿创新 PA 绿脓杆菌 tRNA 谷氨酰胺

Accurate localization and excision of genomic islands in four strains of Pseudomonas aeruginosa and Pseudomonas fluorescens

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Chinese Science Bulletin 2011年第10期56卷 987-995页

Mobile genomic islands (GIs) can be excised from the chromosome,then form a circular intermediate and be reintegrated into the chromosome by the GI internal *** mobile GIs can also be transferred into a new receptor cell by transformation,conjugation,or *** action sites of the integrase are usually flanked direct repeats (DRs) of the *** localization of the flanking sequences is a precondition for determining the mobility of the *** GIs are generally associated with transfer RNAs (tRNAs).Based on the correlation between flanking sequences and tRNA sequences,the flanking sequences of 11 putative mobile GIs in Pseudomonas aeruginosa PAO1,*** PA14,*** Pf-5 and *** Pf0-1 were *** the 11 GIs,Pf0-1GI-1 is responsible for benzoate ***1GI-1,Pf5GI-2,Pf5GI-3,and Pf5GI-4 were confirmed experimentally to be excised from a chromosome to form a circular *** action sites of the integrases are these GIs direct *** to distinct DRs,cutting sites for the internal integrase of PAO1GI-1,Pf5GI-2,Pf5GI-3 and Pf5GI-4 were determined outside the T-loop of the tRNA Gly gene,outside the anticodon loop of the tRNA Ser gene and tRNALys gene,and at the asymmetric 3'-end of the tRNA Leu gene,***1GI-1 and other mobile GIs may be transferred into many different strains that belong to different phyla because of the clear flanking *** study describes basic information about the action sites of the integrases,assesses the mobility of GIs,and can help design and transfer mobile GIs to candidate strains.

关键词：荧光假单胞菌铜绿假单胞菌准确定位基因组移动GIS 地理信息系统侧翼序列地理标志

Intrinsically Anti-Flammable Apigenin-derived Epoxy Thermosets with High Glass Transition Temperature and Mechanical Strength

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Chinese Journal of Polymer Science 2022年第10期40卷 1259-1268,I0011页

作者： Hafezeh Nabipour Xin Wang lei song Yuan Hu State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China

In this work,apigenin was chosen as a raw material to synthesize a novel epoxy monomer(DGEA),while the bio-based epoxy resin was further obtained after curing with 4,4’-diaminodiphenylmethane(DDM).The control samples were prepared by curing diglycidyl ether of bisphenol A(DGEBA)with *** non-isothermal differential scanning calorimeter(DSC)method was utilized to further investigate the curing behavior and curing kinetics of the DGEA/DDM *** no flame retardant active elements,the DGEA/DDM thermoset still exhibited exceptional ***,the DGEA/DDM thermoset reached a V-0 rating in the UL-94 test and owned a high limiting oxygen index(LOI)value of 37.0%,while DGEBA/DDM resins were consumed completely in the vertical combustion test with a low LOI of 23.0%.Furthermore,the microscale combustion calorimetry(MCC)results manifested that compared with DGEBA/DDM resins,both PHRR and THR values of the DGEA/DDM resins were dropped by 84.0%and 57.6%,***,the DGEA/DDM resin also presented higher storage modulus and tensile strength compared with DGEBA/DDM ***,in contrast with that of the cured DGEBA/DDM one(156℃),the DGEA/DDM thermoset displayed an extremely high glass transition temperature(232℃).This study breaks new ground on how to produce biobased monomers with aromatic structures and achieve high-performance thermosetting polymers.

关键词： Bio-based epoxy thermosets Apigenin Intrinsic anti-flammability

Influence of stealth aircraft dynamic RCS peak on radar detection probability

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Chinese Journal of Aeronautics 2023年第3期36卷 137-145页

作者： Xiaoqiang LU Jun HUANG Yacong WU lei song School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

For modern stealth aircraft,it is important to analyze the influence of Radar Cross Section(RCS)peak exposure on penetration for guiding stealth design and penetration trajectory planning,which needs to reflect the RCS statistical uncertainty and the RCS difference with the change of incident *** on the RCS characteristics of typical stealth aircraft,this paper established a simplified RCS dynamic fluctuation statistical model with the parameters log mean and log standard *** to the detection probability algorithm in radar signal processing field,this paper built the algorithm of radar detection probability based on the RCS dynamic fluctuation statistical *** analysis of examples concluded that the key to successful penetration is to shorten the RCS peak exposure time,which can be reduced by decreasing the RCS peak width or increasing *** on the conclusion,this paper proposed the method of turning maneuvering to reduce RCS peak exposure time dramatically.

关键词： Maneuver Penetration RCS RCS fluctuation statistical model RCS peak exposure time RCS peak width Stealth Trajectory planning

Energy and comfort performance of occupant-centric air conditioning strategy in office buildings with personal comfort devices

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Building Simulation 2022年第5期15卷 899-911页

作者： Jingsi Zhang Xiang Zhou song lei Maohui Luo School of Mechanical Engineering Tongji UniversityShanghai 200092China East China Architectural Design and Research Institute 151 Hankou RoadShanghaiChina

The personal comfort system(PCS)aims to meet individual thermal comfort demands efficiently to achieve higher thermal comfort satisfaction while reducing air conditioning energy *** date,many PCS devices have been developed and evaluated from the perspective of thermal *** will be useful for future PCS development if an approach to quantify the thermal comfort and energy performance of certain PCS devices and their combinations with consideration of user behaviors can be *** study attempted to fill this gap by integrating thermal comfort experiments,occupancy simulations,usage behavior modeling,and building energy simulation ***,human subject experiments were conducted to quantify the thermal comfort effects of the ***,the Markov chain model and conditional probability model were employed to describe the room occupancy and PCS usage ***,the extended comfort temperature range and user behavior models were imported into the building energy simulation tool to analyze the energy-saving potential of the *** results show that the use of PCS can significantly improve occupants,thermal comfort and satisfaction rate under both warm and cool *** a cooling cushion and desktop fan can lift the upper limit of the comfortable temperature to 29.5℃while the heated cushion can extend the lower limit to 15℃.By increasing the air conditioning temperature setpoint by 2℃in summer and reducing by 2.5℃the heating temperature setpoint in winter,PCS devices can reduce heating and air conditioning energy consumption by 25%-40%while maintaining occupants’thermal comfort.

关键词： thermal comfort personal comfort system occupant behavior building energy simulation building energy saving