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Analytical and Traveling Wave Solutions to the Fifth Order Standard Sawada-Kotera Equation via the Generalized exp(-Φ(ξ))-Expansion Method 被引量:1
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作者 M. Y. Ali M. G. Hafez +1 位作者 M. K. H. Chowdury M. T. Akter 《Journal of Applied Mathematics and Physics》 2016年第2期262-271,共10页
In this article, we propose a generalized exp(-Φ(ξ))-expansion method and successfully implement it to find exact traveling wave solutions to the fifth order standard Sawada-Kotera (SK) equation. The exact traveling... In this article, we propose a generalized exp(-Φ(ξ))-expansion method and successfully implement it to find exact traveling wave solutions to the fifth order standard Sawada-Kotera (SK) equation. The exact traveling wave solutions are established in the form of trigonometric, hyperbolic, exponential and rational functions with some free parameters. It is shown that this method is standard, effective and easily applicable mathematical tool for solving nonlinear partial differential equations arises in the field of mathematical physics and engineering. 展开更多
关键词 Generalized exp(-Φ(ξ))-Expansion Method Fifth order Standard Sawada-Kotera Equation SOLITONS Periodic Wave Solutions
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Decomposition Theorems for Semi-order Fuzzy Supermartingales and Submartingales
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作者 冯玉瑚 《Journal of China Textile University(English Edition)》 EI CAS 2000年第2期96-99,共4页
Based on semi - order fuzzy supermaringales andsubmartingales, the semi- order fuzzy supermartingaleand submartingale theory is developed. The main resultis to generalize the Doob decomposition and the Riesz de-compos... Based on semi - order fuzzy supermaringales andsubmartingales, the semi- order fuzzy supermartingaleand submartingale theory is developed. The main resultis to generalize the Doob decomposition and the Riesz de-composition theorems of standard martingale theory tosemi - order fuzzy supermaringales and submartingales.The structure of semi - order fuzzy supermaringales andsubmartingales and the conditions of that they has Doobdecomposition (resp. Riesz decomposition) are discussedin detail. 展开更多
关键词 Semi - order FUZZY SUPERMARTINGALE submartin-gale Doob DECOMPOSITION RIESZ DECOMPOSITION .
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Assembling Tunable Time-Resolved Fluorescence Layer onto Nano-Gold
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作者 贺全国 张永强 聂立波 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第2期152-157,共6页
The assembling of a coating of time-resolved fluorescent chelator BSPDA ( abbreviated for 4, 7-bis ( sulfhydrylphenyl)-1, 10-phenanthroline-2, 9-dicarboxylic acid) onto a nano-gold layer was demonstrated. First, B... The assembling of a coating of time-resolved fluorescent chelator BSPDA ( abbreviated for 4, 7-bis ( sulfhydrylphenyl)-1, 10-phenanthroline-2, 9-dicarboxylic acid) onto a nano-gold layer was demonstrated. First, BSPDA was synthesized by simple procedures, and then an approach was developed to immobilize BSPDA onto the nano-gold layer deposited on a silane modified glass substrate, whereby europium ion (Ⅲ, Eu^3+ ) was captured and released owing to the interactive process of complexation and dissociation between BSPDA functionalized coating and Eu^3+ solution. The fluorescence spectra and related lifetimes were determined. Also, the BSPDA functionalized coating's specific complexation with Eu^3+ on the BSPDA assembly layer and the nonspecific adsorption of Eu^3+ on the nano-gold layer were compared. These results allowed a selective complexation of Eu^3+ by assembling a BSPDA chelating layer on the nano-gold layer; thus, a tunable time-resolved fluorescent layer was covalently attached, The results of the nanoparticle assembling and probing (or labeling) processes to specific bio-systems were very interesting and had significant implications to time-resolved-fluorescence-based detection on biosensor surfaces such as DNA chip and to arrayed light display devices. 展开更多
关键词 assembly 4 7-bis sulfhydrylphenyl -1 10-phenanthroline-2 9-dicarboxylic acid (BSPDA) EUROPIUM time-resolved fluorescence NANO-GOLD comolexation
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O(t^(-β))-SYNCHRONIZATION AND ASYMPTOTIC SYNCHRONIZATION OF DELAYED FRACTIONAL ORDER NEURAL NETWORKS
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作者 Anbalagan PRATAP Ramachandran RAJA +3 位作者 Jinde CAO Chuangxia HUANG Jehad ALZABUT Ovidiu BAGDASAR 《Acta Mathematica Scientia》 SCIE CSCD 2022年第4期1273-1292,共20页
This article explores the O(t^(-β))synchronization and asymptotic synchronization for fractional order BAM neural networks(FBAMNNs)with discrete delays,distributed delays and non-identical perturbations.By designing ... This article explores the O(t^(-β))synchronization and asymptotic synchronization for fractional order BAM neural networks(FBAMNNs)with discrete delays,distributed delays and non-identical perturbations.By designing a state feedback control law and a new kind of fractional order Lyapunov functional,a new set of algebraic sufficient conditions are derived to guarantee the O(t^(-β))Synchronization and asymptotic synchronization of the considered FBAMNNs model;this can easily be evaluated without using a MATLAB LMI control toolbox.Finally,two numerical examples,along with the simulation results,illustrate the correctness and viability of the exhibited synchronization results. 展开更多
关键词 O(t^(-β))-synchronization asymptotic synchronization BAM neural networks fractional order state feedback control law
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Reviewers listed by alphabetical order for Journal of Forestry Research in 2007-2008
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《Journal of Forestry Research》 SCIE CAS CSCD 2008年第4期346-348,共3页
关键词 Reviewers listed by alphabetical order for Journal of Forestry Research in 2007-2008
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On the Caginalp for a Conserve Phase-Field with a Polynomial Potentiel of Order 2<i>p</i>- 1
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作者 Narcisse Batangouna Cyr Séraphin Ngamouyih Moussata Urbain Cyriaque Mavoungou 《Journal of Applied Mathematics and Physics》 2020年第12期2744-2756,共13页
Our aim in this paper is to study on the Caginalp for a conserved phase-field with a polynomial potentiel of order 2<em>p</em> - 1. In this part, one treats the conservative version of the problem of gener... Our aim in this paper is to study on the Caginalp for a conserved phase-field with a polynomial potentiel of order 2<em>p</em> - 1. In this part, one treats the conservative version of the problem of generalized phase field. We consider a regular potential, more precisely a polynomial term of the order 2<em>p</em> - 1 with edge conditions of Dirichlet type. Existence and uniqueness are analyzed. More precisely, we precisely, we prove the existence and uniqueness of solutions. 展开更多
关键词 A Conserved Phase-Field Polynomial Potentiel of order 2p - 1 Dirichlet Boundary Conditions Maxwell-Cattaneo Law
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Synthesis of Si-and Ti-MCM-41 Mesostructures via a Novel S^+X^-I^+ Assembly 被引量:1
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作者 Zhao Rong ZHANQ Ji Shuan SUO +1 位作者 Xiao Ming ZHANG Shu Ben LI(State Key Laboratory for Oxo Synthesis and Selective oxidation, Lanzhou Institute of ChemicalPhysics, CAS, 342 Tianshui Road, Lanzhou 730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第5期487-490,共4页
Well-defined Si- and Ti-MCM-41 mesoporous molecular sieves were synthesized in high yields through the halogen anion mediated S(+)X(-)I(+) assembly in the presence of cetylpyridinium bromide as template. The spectrosc... Well-defined Si- and Ti-MCM-41 mesoporous molecular sieves were synthesized in high yields through the halogen anion mediated S(+)X(-)I(+) assembly in the presence of cetylpyridinium bromide as template. The spectroscopy characterization of the as-synthesized samples confirmed that Ti (IV) could be isolated in the lattice positions of the MCM-41 mesostructure by this method. 展开更多
关键词 Si-MCM-41 TI-MCM-41 MESOSTRUCTURE cetylpyridinium bromide S(+)X(-)I(+) assembly
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High-Order BAM, Its Modifications and Performance Analyses
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作者 郑建立 陈松灿 《Journal of China Textile University(English Edition)》 EI CAS 1998年第4期27-30,共4页
Based on Tai’ s high - order bidirectional associative memory ( HOBAM) and Stmposon’ s intraconnected BAM (IBAM) , two Improved models are first presented and discussed in this paper. The improved models not only re... Based on Tai’ s high - order bidirectional associative memory ( HOBAM) and Stmposon’ s intraconnected BAM (IBAM) , two Improved models are first presented and discussed in this paper. The improved models not only retain the advantages of both HOBAM and ISAM but overcome the shortcomings of Kosko’ s BAM also. Secondly their recall stabilities in synchronous and asyn-chronous update modes have been proven by defining corresponding energy functions which decrease as the re-call process proceeds such that the systems can ensure all the training pattern pairs to become local minima of the energy surfaces. Finally with signal - to - noise ratio (SNR) approach, we show that their storage capacities and error correction capabilities are better than that of the HOBAM. 展开更多
关键词 BIDIRECTIONAL ASSOCIATIVE memory ( BAM ) higher - order stability capacity SNR intraconnection neu-ral network
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β-胡萝卜合成途径的不同启动子组合的比较研究
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作者 童阳阳 高书良 +3 位作者 蒋宇 杨晟 戈梅 陈代杰 《工业微生物》 CAS 2017年第3期9-13,共5页
以耶氏解脂酵母菌(Yarrowialipolytica)MYA2613为底盘菌,表达来源于卷枝毛霉菌(Mucorcircinelloides)的基因car B,carRP后能有效生产β-胡萝卜素。启动子作为调控基因的重要顺式元件影响着基因的表达。为了优化基因GGS1,car B,carRP的... 以耶氏解脂酵母菌(Yarrowialipolytica)MYA2613为底盘菌,表达来源于卷枝毛霉菌(Mucorcircinelloides)的基因car B,carRP后能有效生产β-胡萝卜素。启动子作为调控基因的重要顺式元件影响着基因的表达。为了优化基因GGS1,car B,carRP的表达强度组合,将上述3个基因、终止子与两组不同的启动子通过DNA assemble方法拼接后,得到了组合TEF1p-GGS1-xpr2t-GPD1pcar B-mig1t-EXP1p-carRP-lip2t和YAT1p-GGS1-xpr2t-GPD1p-car B-mig1t-FBAin1p-carRP-lip2t。经发酵表型验证,两株菌都产β-胡萝卜素,其中前者的产量是后者的4.18倍,具有明显优势。 展开更多
关键词 Β-胡萝卜素 DNA assemble 耶氏解脂酵母 启动子组合
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Insights into the enhanced structure stability and electrochemical performance of Ti^(4+)/F^(-) co-doped P2-Na_(0.67)Ni_(0.33)Mn_(0.67)O_(2) cathodes for sodium ion batteries at high voltage 被引量:4
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作者 Pengfei Zhou Jing Zhang +6 位作者 Zhennan Che Zuhao Quan Ju Duan Xiaozhong Wu Junying Weng Jinping Zhao Jin Zhou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第4期655-662,共8页
P2-Na_(0.67)N_(i0.33)Mn_(0.67)O_(2)is considered as a promising cathode material for sodium-ion battery (SIBs)because of its high capacity and discharge potential.However,its practical use is limited by Na^(+)/vacancy... P2-Na_(0.67)N_(i0.33)Mn_(0.67)O_(2)is considered as a promising cathode material for sodium-ion battery (SIBs)because of its high capacity and discharge potential.However,its practical use is limited by Na^(+)/vacancy ordering and P2-O2 phase transition.Herein,a Ti^(4+)/F^(-) co-doping strategy is developed to address these issues.The optimal P2-Na_(0.67)Ni_(0.33)Mn_(0.37)Ti_(0.3)O_(1.9)F_(0.1) exhibits much enhanced sodium storage performance in the high voltage range of 2.0–4.4 V,including a cycling stability of 77.2%over 300cycles at a rate of 2 C and a high-rate capability of 87.7 m Ah g^(-1) at 6 C.Moreover,the P2-Na_(0.67)Ni_(0.33)Mn_(0.37)Ti_(0.3)O_(1.9)F_(0.1) delivers reversible capacities of 82.7 and 128.1 m Ah g^(-1) at-10 and 50℃ at a rate of 2 C,respectively.The capacity retentions over 200 cycles at-10℃ is 94.2%,implying more opportunity for practical application.In-situ X-ray diffraction analysis reveals that both P2-O2 phase transitions and Na^(+)/vacancy ordering is suppressed by Ti^(4+)/F^(-) co-doping,which resulting in fast Na^(+) diffusion and stable phase structure.The hard carbon//P2-Na_(0.67)Ni_(0.33)Mn_(0.37)Ti_(0.3)O_(1.9)F_(0.1) full cell exhibits a high energy density of 310.2 Wh kg^(-1) and remarkable cyclability with 82.1%retention after 300 cycles at 1 C in the voltage range of 1.5–4.2 V.These results demonstrate that the co-doping Ti^(4+)/F^(-) is a promising strategy to improve the electrochemical properties of P2-Na_(0.67)Ni_(0.33)Mn_(0.67)O_(2),providing a facile tactic to develop high performance cathode materials for SIBs. 展开更多
关键词 P2-Na_(0.67)N_(i0.33)Mn_(0.67)O_(2) Ti^(4+)/F^(-)co-doping Phase transition Na^(+)/vacancy ordering Sodium-ion batteries
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Plasma microRNA-15a/16-1-based machine learning for early detection of hepatitis B virus-related hepatocellular carcinoma
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作者 Huan Wei Songhao Luo +4 位作者 Yanhua Bi Chunhong Liao Yifan Lian Jiajun Zhang Yuehua Huang 《Liver Research》 CSCD 2024年第2期105-117,共13页
Background and aims:Hepatocellular carcinoma(HCC),which is prevalent worldwide and has a high mortality rate,needs to be effectively diagnosed.We aimed to evaluate the significance of plasma microRNA-15a/16-1(miR-15a/... Background and aims:Hepatocellular carcinoma(HCC),which is prevalent worldwide and has a high mortality rate,needs to be effectively diagnosed.We aimed to evaluate the significance of plasma microRNA-15a/16-1(miR-15a/16)as a biomarker of hepatitis B virus-related HCC(HBV-HCC)using the machine learning model.This study was the first large-scale investigation of these two miRNAs in HCC plasma samples.Methods:Using quantitative polymerase chain reaction,we measured the plasma miR-15a/16 levels in a total of 766 participants,including 74 healthy controls,335 with chronic hepatitis B(CHB),47 with compensated liver cirrhosis,and 310 with HBV-HCC.The diagnostic performance of miR-15a/16 was examined using a machine learning model and compared with that of alpha-fetoprotein(AFP).Lastly,to validate the diagnostic efficiency of miR-15a/16,we performed pseudotemporal sorting of the samples to simulate progression from CHB to HCC.Results:Plasma miR-15a/16 was significantly decreased in HCC than in all control groups(P<0.05 for all).In the training cohort,the area under the receiver operating characteristic curve(AUC),sensitivity,and average precision(AP)for the detection of HCC were higher for miR-15a(AUC=0.80,67.3%,AP=0.80)and miR-16(AUC=0.83,79.0%,AP=0.83)than for AFP(AUC=0.74,61.7%,AP=0.72).Combining miR-15a/16 with AFP increased the AUC to 0.86(sensitivity 85.9%)and the AP to 0.85 and was significantly superior to the other markers in this study(P<0.05 for all),as further demonstrated by the detection error tradeoff curves.Moreover,miR-15a/16 impressively showed potent diagnostic power in early-stage,small-tumor,and AFP-negative HCC.A validation cohort confirmed these results.Lastly,the simulated follow-up of patients further validated the diagnostic efficiency of miR-15a/16.Conclusions:We developed and validated a plasma miR-15a/16-based machine learning model,which exhibited better diagnostic performance for the early diagnosis of HCC compared to that of AFP. 展开更多
关键词 Hepatitis B virus-related hepatocellular carcinoma(HBV-HCC) microRNA-15a microRNA-16-1 BIOMARKER Machine learning Pseudotemporal ordering
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Selective Construction of Borromean Rings and Tweezer-Like Molecular Assembly Featuring Cp^(*)Rh/Ir Clips for Near-Infrared Photothermal Conversion
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作者 Yan Zou Hai-Ning Zhang +2 位作者 Qiu-Shui Mu Li-Long Dang Guo-Xin Jin 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2023年第23期3229-3237,共9页
Making full use of coordination-driven self-assembly strategy,we herein described the selective synthesis of a molecular Borromean rings and two cases of “U”-shaped tweezer-like molecular assemblies in high yield by... Making full use of coordination-driven self-assembly strategy,we herein described the selective synthesis of a molecular Borromean rings and two cases of “U”-shaped tweezer-like molecular assemblies in high yield by using bipyridyl ligands based on biphenyl unit and half-sandwich binuclear rhodium(III)/iridium(III) building blocks.The selective synthesis was realized by adjusting the length of dipyridyl arms.The utilization of curved U-shaped bipyridyl ligand L1 led to tweezer-like molecular assemblies.Subsequently,olefinic bonds were introduced to elongate dipyridyl arms obtaining ligand L2.The ligand L2 has two stable conformations,U-shape and Z-shape,which facilitated the formation of different topologies including the tetranuclear macrocycle and Borromean rings with different building blocks in this work.These structures in solid and solution all have been further confirmed by single-crystal X-ray diffraction,NMR analysis,and mass spectrometry.In addition,as an important driving force,π-π stacking interactions not only played a significant role in the stability of structures but also further triggered photothermal conversion in solution.The experimental results demonstrated that compounds 1a and 2 had good NIR photothermal conversion efficiency (11.83% and 17.76%),and further analysis found the photothermal conversion efficiency had a gradual increase in the trend with the π-π stacking interactions increasing.This research expands the application of topological structures in materials science and provides a new idea for the synthesis of novel photothermal conversion materials. 展开更多
关键词 Self-assembly π-πstacking interaction Half-sandwich Cp*Rh/Ir Rhodium Iridium Borromean rings and Tweezer-like molecular assembly Near-infrared photothermal conversion
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SOME EULER SPACES OF DIFFERENCE SEQUENCES OF ORDER m 被引量:5
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作者 Harun Polat Feyzi Basar 《Acta Mathematica Scientia》 SCIE CSCD 2007年第2期254-266,共13页
Kizmaz [13] studied the difference sequence spaces ∞(A), c(A), and co(A). Several article dealt with the sets of sequences of m-th order difference of which are bounded, convergent, or convergent to zero. Alta... Kizmaz [13] studied the difference sequence spaces ∞(A), c(A), and co(A). Several article dealt with the sets of sequences of m-th order difference of which are bounded, convergent, or convergent to zero. Altay and Basar [5] and Altay, Basar, and Mursaleen [7] introduced the Euler sequence spaces e0^r, ec^r, and e∞^r, respectively. The main purpose of this article is to introduce the spaces e0^r△^(m)), ec^r△^(m)), and e∞^r△^(m))consisting of all sequences whose mth order differences are in the Euler spaces e0^r, ec^r, and e∞^r, respectively. Moreover, the authors give some topological properties and inclusion relations, and determine the α-, β-, and γ-duals of the spaces e0^r△^(m)), ec^r△^(m)), and e∞^r△^(m)), and the Schauder basis of the spaces e0^r△^(m)), ec^r△^(m)). The last section of the article is devoted to the characterization of some matrix mappings on the sequence space ec^r△^(m)). 展开更多
关键词 Difference sequence spaces of order m Schauder basis the α- β- and γ-duals matrix mappings
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An Improved Numerical Simulation Mode of Nonlinear Wave with Consideration of High Order Terms
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作者 孙大鹏 包伟斌 +1 位作者 吴浩 李玉成 《China Ocean Engineering》 SCIE EI 2011年第4期687-697,共11页
SUN Da-peng BAO Wei-bin, WU Hao and LI Yu-cheng ( In this paper the 0-1 combined BEM is adopted to subdivide the computational domain boundary, and to discretize the Green's integral expression based on Laplace equ... SUN Da-peng BAO Wei-bin, WU Hao and LI Yu-cheng ( In this paper the 0-1 combined BEM is adopted to subdivide the computational domain boundary, and to discretize the Green's integral expression based on Laplace equation. The FEM is used to subdivide the wave surface and deduce the surface equation which satisfies the nonlinear boundary conditions on the surface. The equations with potential function and wave surface height as an unknown quantity by application of Taylor expansion approach can be solved by iteration within the time step. In m-time iteration within the computational process of time step (n-1)At to nat, the results of the previous iteration are taken as the initial value of the two-order unknown terms in the present iteration. Thus, an improved tracking mode of nonlinear wave surface is estabIished, and numerical results of wave tank test indicate that this mode is improved obviously and is more precise than the previous numerical model which ignored the two-order unknown terms of wave surface location and velocity potential function in comparison with the theoretical values. 展开更多
关键词 Laplace equation nonlinear wave 0-1 combined type BEM FEM two order terms
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Interfacial assembly and host-guest interaction of anthracene-conjugated L-glutamate dendron with cyclodextrin at the air/water interface 被引量:3
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作者 Long Qin Peng-Fei Duan Ming-Hua Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第4期487-490,共4页
The interracial assembly of photo-induced dimerization of atypical anthracene-containing amphiphilic dendron and host-guest interaction with γ-cyclodextrin has been investigated. It has been proved that even without ... The interracial assembly of photo-induced dimerization of atypical anthracene-containing amphiphilic dendron and host-guest interaction with γ-cyclodextrin has been investigated. It has been proved that even without long alkyl chain the amphiphilic dendron could still form stable Langmuir monolayer at the air/water interface. Through the host-guest interaction,γ-cyclodextrin can be used to encapsulate two headgroups of amphiphilic dendron in the antiparallel direction. However, the formed host-guest complex was sensitive to the surface pressure. Slight compression of surface pressure led amphiphilic dendron to reassemble into nanofibers through the strong π-π stacking between headgroups. On the other hand, under in situ irradiation, the amphiphilic dendron was stabilized in the cavity of γ- cyclodextrin through headgroup dimerization and the host-guest complex further irregularly aggregated to nanoparticles. Meanwhile, γ-cyclodextrin, as a silencer, blocked the supramolecular chirality transfer. Our conclusion was demonstrated through UV/vis, FT-IR, CD spectrum and AFM images, respectively. 展开更多
关键词 Dendron γ-Cyclodextrin Host-guest complex π-π stacking Supramolecular assembly
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Involvement of unusual noncovalent interactions in the self-assembly of cucurbit[6]uril with [CdCl_4]^(2-) anions
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作者 Xiao-Wei Cui Shi-Yan Chen +5 位作者 Chuan-Zeng Wang Wen-Xuan Zhao Tao Sun Xin-Long Ni Yun-Qian Zhang Zhu Tao 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第1期173-177,共5页
The [CdCl_4]^(2-) anion as a structure inducer has proved to be useful in the construction of cucurbit[n]urilmetal coordination architectures and materials. In order to better understand the role and influence of th... The [CdCl_4]^(2-) anion as a structure inducer has proved to be useful in the construction of cucurbit[n]urilmetal coordination architectures and materials. In order to better understand the role and influence of the structure inducer in Q[n] systems, we report herein the self-assembly of Q[6] solely in the presence of[CdCl_4]^(2-)anions and in the presence of both a linear cationic organic guest and [CdCl_4]^(2-)anions. X-ray diffraction analysis revealed that 1D Q[6] porous channels were formed by the noncovalent interactions between Q[6] and [CdCl_4]^(2-)anions, but the ''honeycomb effect'' was not observed in the present study.However, it seems that the ''honeycomb effect'' and the self-assembly of Q[6] with [CdCl_4]^(2-)anions can be significantly modified and switched in the presence of a linear cationic dibutylamine guest through some unusual noncovalent interactions. 展开更多
关键词 uril [CdCl_4]^(2- anions Cationic guest Honeycomb effect assembly
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基于离散-连续选择模型的通勤出行时间预测 被引量:2
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作者 宗芳 隽志才 贾广辉 《系统工程理论与实践》 EI CSSCI CSCD 北大核心 2013年第10期2679-2684,共6页
把握出行者的日时间分配是交通行为分析的重要内容之一.本文基于离散-连续建模思想,结合运用Ordered Probit离散选择模型和Hazard连续选择模型,建立了由上班(上学),下班(放学)出发时刻模型和上班(上学),下班(放学)出行耗时模型组成的通... 把握出行者的日时间分配是交通行为分析的重要内容之一.本文基于离散-连续建模思想,结合运用Ordered Probit离散选择模型和Hazard连续选择模型,建立了由上班(上学),下班(放学)出发时刻模型和上班(上学),下班(放学)出行耗时模型组成的通勤时间预测模型系统,预测了通勤者的日时间安排.研究表明,所建模型能够以较高的预测精度,预测通勤者的活动-出行时间安排.研究将为活动-出行行为的整体建模预测和分析奠定时间轴预测基础,为城市居民的交通行为分析提供模型工具,为制定交通管理政策,解决城市交通拥挤问题提供决策分析依据. 展开更多
关键词 通勤出行 活动 时间安排 出发时刻 出行耗时 离散-连续模型 orderED PROBIT模型 Hazard模型
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Magnetogenetics: remote non-invasive magnetic activation of neuronal activity with a magnetoreceptor 被引量:22
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作者 Xiaoyang Long Jing Ye +1 位作者 Di Zhao Sheng-Jia Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2015年第24期2107-2119,共13页
Current neuromodulation techniques such as optogenetics and deep-brain stimulation are transforming basic and translational neuroscience. These two neuro- modulation approaches are, however, invasive since surgical im... Current neuromodulation techniques such as optogenetics and deep-brain stimulation are transforming basic and translational neuroscience. These two neuro- modulation approaches are, however, invasive since surgical implantation of an optical fiber or wire electrode is required. Here, we have invented a non-invasive magnetogenetics that combines the genetic targeting of a mag- netoreceptor with remote magnetic stimulation. The noninvasive activation of neurons was achieved by neuronal expression of an exogenous magnetoreceptor, an iron-sulfur cluster assembly protein 1 (Iscal). In HEK-293 cells and cultured hippocampal neurons expressing this magnetoreceptor, application of an external magnetic field resulted in membrane depolarization and calcium influx in a reproducible and reversible manner, as indicated by the ultrasensitive fluorescent calcium indicator GCaMP6s.Moreover, the magnetogenetic control of neuronal activity might be dependent on the direction of the magnetic field and exhibits on-response and off-response patterns for the external magnetic field applied. The activation of this magnetoreceptor can depolarize neurons and elicit trains of action potentials, which can be triggered repetitively with a remote magnetic field in whole-cell patch-clamp recording. In transgenic Caenorhabditis elegans expressing this magnetoreceptor in myo-3-specific muscle cells or mec-4- specific neurons, application of the external magnetic field triggered muscle contraction and withdrawal behavior of the worms, indicative of magnet-dependent activation of muscle cells and touch receptor neurons, respectively. The advantages of magnetogenetics over optogenetics are its exclusive non-invasive, deep penetration, long-term continuous dosing, unlimited accessibility, spatial uniformity and relative safety. Like optogenetics that has gone through decade-long improvements, magnetogenetics, with continuous modification and maturation, will reshape the current landscape of neuromodulation toolboxes and will have a broad range of applications to basic and translational neuroscience as well as other biological sciences. We envision a new age of magnetogenetics is coming. 展开更多
关键词 Magnetogenetics - Optogenetics Iron-sulfur cluster assembly protein Magnetoreceptor Non-invasive and remote activation Neuronalactivity and circuit
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Economic appraisal of shale gas resources, an example from the Horn River shale gas play, Canada 被引量:2
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作者 Zhuoheng Chen Kirk G.Osadetz Xuansha Chen 《Petroleum Science》 SCIE CAS CSCD 2015年第4期712-725,共14页
Development of unconventional shale gas resources involves intensive capital investment accompa- nying large commercial production uncertainties. Eco- nomic appraisal, bringing together multidisciplinary project data ... Development of unconventional shale gas resources involves intensive capital investment accompa- nying large commercial production uncertainties. Eco- nomic appraisal, bringing together multidisciplinary project data and information and providing likely economic outcomes for various development scenarios, forms the core of business decision-making. This paper uses a dis- counted cash flow (DCF) model to evaluate the economic outcome of shale gas development in the Horn River Basin, northeastern British Columbia, Canada. Through numerical examples, this study demonstrates that the use of a single average decline curve for the whole shale gas play is the equivalent of the results from a random drilling process. Business decision based on a DCF model using a single decline curve could be vulnerable to drastic changes of shale gas productivity across the play region. A random drilling model takes those drastic changes in well estimated ultimate recovery (EUR) and decline rates into account in the economic appraisal, providing more information useful for business decisions. Assuming a natural gas well-head price of S4/MCF and using a 10 % discount rate, the results from this study suggest that a random drilling strategy (e.g., one that does not regard well EURs), could lead to a negative net present value (NPV); whereas a drilling sequence that gives priority to developing those wells with larger EURs earlier in the drilling history could result in a positive NPV with various payback time and internal rate of return (IRR). Under a random drilling assumption, the breakeven price is S4.2/MCF with more than 10 years of payout time. In contrast, if the drilling order is strictly proportional to well EURs, the result is a much better economic outcome with a breakeven price below the assumed well-head price accompanied by a higher IRR. 展开更多
关键词 Drilling order EUR Risk aversion - Shalepetroleum resource
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Road traffic congestion measurement considering impacts on travelers 被引量:2
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作者 Liang Ye Ying Hui Dongyuan Yang 《Journal of Modern Transportation》 2013年第1期28-39,共12页
The article intends to find a method to quantify traffic congestion's impacts on travelers to help transportation planners and policy decision makers well understand congestion situations. Three new congestion indica... The article intends to find a method to quantify traffic congestion's impacts on travelers to help transportation planners and policy decision makers well understand congestion situations. Three new congestion indicators, including transportation environment satisfaction (TES), travel time satisfaction (TTS), and traffic congestion frequency and feeling (TCFF), are defined to estimate urban traffic congestion based on travelers' feelings. Data of travelers' attitude about congestion and trip information were collected from a survey in Shanghai, China. Based on the survey data, we estimated the value of the three indi- cators. Then, the principal components analysis was used to derive a small number of linear combinations of a set of variables to estimate the whole congestion status. A linear regression model was used to find out the significant variables which impact respondents' feelings. Two ordered logit models were used to select significant variables of TES and TTS. Attitudinal factor variables were also used in these models. The results show that attitudinal factor variables and cluster category variables are as important as sociodemographic variables in the models. Using the three congestion indicators, the government can collect travelers' feeling about traffic congestion and estimate the transportation policy that might be applied to cope with traffic congestion. 展开更多
关键词 Traffic congestion indicator Attitudinalfactor variable Linear regression model - ordered logitmodel
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