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产业链韧性测度方法研究进展

经济学动态 2024年第4期 144-160页

作者：肖兴志王振宇李少林东北财经大学产业组织与企业组织研究中心 116025

产业链韧性测度是识别“断链”风险和维护产业链安全稳定的现实抓手,成为新时代应对、把握和引领大变局亟待解决的热点问题。本文在分析产业链韧性测度现实需求的基础上,从产业链韧性测度的理论基础、方法类型、应用步骤三个方面就经典... 详细信息

产业链韧性测度是识别“断链”风险和维护产业链安全稳定的现实抓手,成为新时代应对、把握和引领大变局亟待解决的热点问题。本文在分析产业链韧性测度现实需求的基础上,从产业链韧性测度的理论基础、方法类型、应用步骤三个方面就经典文献进行述评。首先,围绕恢复、抵抗、适应与变革四大能力追溯概念界定、内涵特征和学科交叉的理论起源;其次,系统梳理了以核心变量法、综合评价法及投入产出法为代表的产业链韧性评价方法,剖析了各自优点与相对不足;最后,全面厘清了“冲击识别—结构分析—韧性评价”框架下的韧性测度理论与方法应用。本文认为,产业链韧性测度方法的选取及应用须高度重视学科交叉的应用场景,廓清理论模型的适用条件,为测度和增强产业链韧性提供多样化、稳健性的方法支撑。

关键词：产业链韧性经济韧性测度方法

Effect of diode size and series resistance on barrier height and ideality factor in nearly ideal Au/n type-GaAs micro Schottky contact diodes

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Chinese Physics B 2010年第10期19卷 477-484页

作者： M. A. Yeganeh sh. Rahmatallahpur A. nozad R. k. Mamedov Faculty of Physics Baku State University Academic Zahid Xlilov Küsi-23 AZ 1148 Iran Material Research School POB 55515196 Binab Iran

Small high-quality Au/n type-GaAs Schottky barrier diodes （SBDs） with low reverse leakage current are produced using lithography. Their effective barrier heights （BHs） and ideality factors from current-voltage （I-V） characteristics are measured by a Pico ampere meter and home-built I-V instrument. In spite of the identical preparation of the diodes there is a diode-to-diode variation in ideality factor and barrier height parameters. Measurement of topology of a surface of a thin metal film with atomic force microscope （AFM） shows that Au-n type-GaAS SD consists of a set of parallel-connected micro and nanocontacts diodes with sizes approximately in a range of 100-200 nm. Between barrier height and ideality factor there is an inversely proportional dependency. With the diameter of contact increasing from 5 μm up to 200 μm, the barrier height increases from 0.833 up to 0.933 eV and its ideality factor decreases from 1.11 down to 1.006. These dependencies show the reduction of the contribution of the peripheral current with the diameter of contact increasing. We find the effect of series resistance on barrier height and ideality factor.

关键词： Schottky barrier diodes conducting probe-atomic force microscope barrier height andideality factor

Mycoendophytic diversity and their antimicrobial potential from two epiphytic orchids of the Western Ghats forests of India

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Studies in Fungi 2020年第1期5卷 113-124页

作者： nuthan BR Rakshith D Marulasiddaswamy kM Ramesha kP Chandra Mohana n Sampath kumara kk Satish S Department of Studies in Microbiology University of MysoreManasagangotriMysuru 570006KarnatakaIndia Department of Microbiology Yuvaraja’s CollegeUniversity of MysoreMysuru 570005KarnatakaIndia Department of Studies in Biotechnology University of MysoreManasagangotriMysuru 570006KarnatakaIndia Government Pre-University College Davangere 577002KarnatakaIndia

The epiphytic plants belong to a group that harmlessly grows on other plants by utilizing the nutrition from the host plants with their unique adaptation features along with symbiotic associations with fungi or *** various biological activities exhibited by the mycoendophytes inhabiting medicinally-important epiphytic orchids serve as the primary source of novel drug leads,industrially-essential enzymes,and plant growth-promoting *** the present study,a total of 956 culturable mycoendophytes out of 1600 segments belonging to 17 genera were isolated from different tissue parts of Trias stocksii and Dendrobium *** Xylariaceae taxa were the predominant mycoendophytes present in both plants,followed by Pestalotiopsis sp.,Colletotrichum sp.,and Fusarium *** estimation of the shannon-Wiener and Simpson diversity indices showed that the bulbs of *** have the highest species diversity index and the stems of *** the *** highest species richness was observed in the leaves of *** and the lowest in the leaves of ***,*** harbored more mycoendophytes along with the highest diversity indices compared to *** antimicrobial evaluation revealed that Xylaria *** a higher potential of producing anti-infectives and opens a new arena for industrial exploration.

关键词： Antimicrobial activity Dendrobium herbaceum Diversity indices Mycoendophytes Trias stocksii Xylaria sp

Effect of tritium reduction in determining energy gain by using R-matrix method direct laser fusion in D-T reaction

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nuclear Science and Techniques 2007年第3期18卷 129-136页

作者： S.n.HOSSEInI MOTLAGH sh.S.MOHAMADY M.kh.MORADkHAnI R.shAMSI Department of Physics Iran University of Science and Technology IranDepartment of PhysicsIran University of Science and Technology IranDepartment of PhysicsIran University of Science and Technology IranDepartment of Industrial EngineeringMazandaran University of Science and Technology Iran

The laser fusion criterion is known as the ρR-Criterion, also called high-gain condition. This parameter is temperature dependent and can be calculated by R-matrix method. This method is applied for determining improved fusion cross-section for the reactions T(d,n)4He, 3He(d,p)4He, D(d,p)T, D(d,n)3He. In this paper the time dependent reaction rate equations for fusion reaction T(d,n)4He are solved and by using the obtained results we computed the fu- sion power density, energy gain versus temperature and ρR-parameter. The obtained results show that a suitable com- bination may be a deuterium fraction fD=0.65 and fT=0.35 which would lead 30% reduction in the tritium content of the fuel mixture, and this choice would not change the energy gain value very much. Finally, the obtained energy gain for D-T reaction by using R-matrix is in good agreement with other theories.

关键词：氘氚反应激光聚合等离子体交叉断面

Mechanical, thermal and fire nanoclay/vinylester retardation behaviours of nanocomposites

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Frontiers of Materials Science 2011年第4期5卷 401-411页

作者： k. R. VIshnU MAHEsh H. n. nARASIMHA MURTHY B. E. kumara SWAMY S. C. shARMA R. SRIDHAR niranjan PATTAR M. kRIshnA B. S. shERIGARA Department of P. G. Studies and Research in Industrial Chemistry Kuvempu University Shankaraghatta Shimoga 577451 Karnataka India Department of Mechanical Engineering R. V. College of Engineering Bangalore 560059 Karnataka India Tumkur University Tumkur 572103 Karnataka India

The dispersion of montmorillonite （MMT） in vinylester for preparing nanoclay/vinylester gel coat was reported. Two sets of MMT/vinylester specimens, namely Type I and Type 2, were prepared for comparative studies. Type I specimens were prepared using ultrasonication only, and Type 2 specimens were prepared using both ultrasonication and twin-screw extrusion. According to XRD and TEM results, Type 2 specimens showed lower levels of nanoclay agglomeration and higher levels o! exfoliation. DSC results showed that the glass transition temperatures of Type 2 specimens are higher than those of Type 1 specimens. TGA results showed that the residual weight of 4 wt.% MMT/vinylester of Type 1 was 7.38%, while the corresponding value of Type 2 was 13,5%, indicating lower thermal degradation in the latter. MMTt vinylester/glass and MMT/vinylester/carbon specimens were fabricated and tested for mechanical and fire retardation behaviours. Type 2 based nanocomposite laminates showed greater values of ultimate tensile strength, flexural strength, interlaminar shear strength, impact strength, horizontal burning rate, and vertical burning rate than Type 1 based laminates. SEM images of tensile fractured surfaces revealed that Type 2 based laminates have no or less agglomeration of nanoclay than Type 1 based laminates.

关键词： twin-screw extrusion montmorillonite nanoclay nanocomposite vinylester

Dry Sliding Oxidative Wear in Plain Carbon Dual Phase Steel

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Journal of Iron and Steel Research International 2007年第4期14卷 43-48页

作者： V Abouei H Saghafian sh kheirandish Department of Metallurgy and Materials Engineering Iran University of Science and TechnologyNarmak 16844TehranIran

To investigate the tribological potential of the dual phase （DP） steel as a wear resistant material, the wear and the friction characteristics of this steel, which consists of hard martensite islands embedded in a ductile ferrite matrix, have been investigated and compared with those observed in plain carbon hardened （H） steel that has the same carbon content of 0.2%. Dry sliding wear tests have been carried out using a pin-on-disk wear testing machine at different normal loads of 21.3 n, 28. 5 n, 35.7 n, and 42.6 n and at a constant sliding velocity of 1.20 m/s. The analysis of surface and wear debris of samples showed that the wear mechanism was mainly mild oxidative. The friction and the wear rate of the H steel and the DP Steel have been explained with respect to the microstructure and the wear mechanism.

关键词： dual phase steel wear microstructure heat treatment

Essential commutant of analytic Toeplitz operators

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Chinese Science Bulletin 1997年第7期42卷 548-552页

作者： Ding, XH Sun, sh Department of Mathematics Sichuan Union University Chengdu China

LET Bn be the unit ball of Cn. The n-dimensional vector space over the complex field C, Sn=（?）Bn is the boundary of Bn. We use σ to denote the unique rotation-invariant probability measure on Sn. The Lebesgue space... 详细信息

关键词： Toeplitz operators inner function essential commutant.

Fluorescence Quenching and Depolarization Studies on Segmental Motion of Poly (n, n-dimethylacrylamide)

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Chinese Chemical Letters 1997年第8期8卷 719-720页

作者： Zhu, CY Wu, sh Li, LR nAnkAI UnIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

A new polymer, poly(n, n-dimethylacrylamide), labeled with acenaphthylene has been synthesized. The rotational relaxation time of this polymer has been studied using steady state fluorescence depolarization measuremen... 详细信息

关键词： Fluorescence Quenching and Depolarization Studies on Segmental Motion of Poly n-dimethylacrylamide

Possible therapeutic targets and promising drugs based on unsymmetrical hetaryl-substituted porphyrins to combat SARS-CoV-2

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Journal of Pharmaceutical Analysis 2021年第6期11卷 691-698页

作者： Yury A.Gubarev natalya sh.Lebedeva Elena S.Yurina Sergey A.Syrbu Aleksey n.kiselev Mikhail A.Lebedev G.A.krestov Institute of Solution Chemistry of the Russian Academy of Sciences 153045IvanovoRussia Ivanovo State University of Chemistry and Technology 153000IvanovoRussia

Coronavirus disease 2019 is a serious disease that causes acute respiratory syndrome and negatively affects the central nervous *** acute respiratory syndrome coronavirus 2(SARS-CoV-2)crosses the blood-brain barrier due to the spike(S) protein on the surface of the viral ***,it is important to develop compounds that not only have an inhibitory effect but are also capable of completely deactivating the S protein *** study describes the purposeful modification of porphyrins and proposes compounds,asymmetrically hetaryl-substituted porphyrins with benzothiazole,benzoxazole,and n-methylbenzimidazole residues,to deactivate the S protein *** docking of SARS-CoV-2 proteins with hetaryl-substituted porphyrins showed that the viral S protein,nucleocapsid(n) protein,and non-structural protein 13(nsp13) exhibited the highest binding ***-substituted porphyrins form strong complexes(13-14 kcal/mol) with the receptor-binding domain of the S protein,while the distance from the porphyrins to the receptor-binding motif(RBM)does not exceed 20 ?;therefore,RBM can be oxidized by ^(1)O_(2),which is generated by *** porphyrins interact with the n protein in the serine/arginine-rich region,and a number of vulnerable amino acid residues are located in the photooxidation *** damage complicates the packaging of viral RnA into new ***-energy binding of hetaryl-substituted porphyrins with the n-and C-terminal domains of nsp13 was *** binding blocks the action of nsp13 as an enzyme of exoribonuclease and methyltransferase,thereby preventing RnA replication and processing.A procedure for the synthesis of hetaryl-substituted porphyrins was developed,new compounds were obtained,their structures were identified,and their photocatalytic properties were studied.

关键词： Porphyrins SARS-CoV-2 Molecular docking Photoinactivation