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Vertical SnS2/Si heterostructure for tunnel diodes

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Science China(Information Sciences) 2020年第2期63卷 189-195页

作者： rundong JIA Qianqian HUANG ru HUANG Key laboratory of Microelectronic Devices and Circuits (MOE) Institute of Microelectronics Peking University

Tunneling FET（TFET） is considered as one of the most promising low-power electronic devices,however, suffers from the low drive current. Heterostructure TFET with low effective tunnel barrier height based on traditional 3D materials can obtain large tunnel current but deteriorated off-state current induced by the lattice mismatch. van der Waals heterostructure TFET based on 2D materials can obtain danglingbond-free interface for suppressed off-state current but face the challenge of controllable and stable doping technology. As the critical building block of the TFET, tunnel diode based on the 2D/3D heterostructure is proposed in this study and experimentally demonstrated. Combination of the pristine interface of 2D materials and matured doping technology in the traditional 3D bulk materials, tunnel diodes based on the 2D/3D heterostructures are expected to realize low leakage current and high on current simultaneously,showing great potential in low-power electronics. The N+SnS2/P+Si heterostructure with effective tunnel barrier of 0.17 eV theoretically is considered for the first time and selected as the optimal material platform for tunnel diodes. The N+SnS2/P+Si tunnel diode demonstrated experimentally shows the high current density of 1 μA/μm2, which is the highest one among the reported tunnel diodes based on the 2D/group IV materials. The tunneling current is also confirmed by low-temperature measurements. This study shows the great potential of the 2D/3D heterostructure for low-power tunneling devices.

关键词： 2D/3D heterostructure SnS2/Si tunnel barrier tunnel diode energy-efficient

Urban Hierarchy of Innovation Capability and Inter-city linkages of Knowledge in Post-reform China

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Chinese Geographical Science 2012年第5期22卷 602-616页

作者： lU lachang HUANG ru College of Resource Environment and Tourism Capital Normal UniversityBeijing 100048China School of Geographical Science Guangzhou UniversityGuangzhou 510006China

The 2000s has witnessed increasing interests in cities′role of innovation in the era of knowledge-based *** with substantial empirical analysis on the world city hierarchy of innovation,this paper attempts to examine the national urban hierarchy of innovation capability in China,in terms of ranking systems,spatial pattern and inter-city linkages of knowledge during the post-reform period since the late *** on quantitative analysis such as principal component factor analysis and clustering analysis,this paper identifies the five-tier hierarchy of in-novation,which is headed by Beijing and Shanghai,followed by the capital cities of each province and regional centre *** development of China′s urban hierarchy of innovation capability has been driven by such factors as the scale of innovation,scientific scale,innovation potential and innovation *** paper further investigates the inter-city linkages of knowledge measured by the number of co-authored papers among the *** is positioned in the central position of the knowledge diffusion and knowledge cooperation *** knowledge diffusion among high level cities has occurred than that among the low level cities as well as between the low level cities and high level cities,and provincial capital cities and the regional central cities.

关键词： urban hierarchy innovation capability inter-city linkages of knowledge Chinese cities

Kinetic Gaussian Model with long-Range Interactions

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Communications in Theoretical Physics 2004年第6X期42卷 913-922页

作者： KONGXiang-Mu YANGZhan-ru DepartmentofPhysicsandInstituteofTheoreticalPhysics BeijingNormalUniversityBeijing100875China//DepartmentofPhysicsQufuNormalUniversityQufu273165China DepartmentofPhysicsandInstituteofTheoreticalPhysics BeijingNormalUniversityBeijing100875China

In this paper dynamical critical phenomena of the Gaussian model with long-range interactions decaying as 1/rd+δ (δ＞ 0) on d-dimensional hypercubic lattices (d = 1, 2, and 3) are studied. First, the critical points are exactly calculated, and it is found that the critical points depend on the value of δ and the range of interactions. Then the critical dynamics is considered. We calculate the time evolutions of the local magnetizations and the spin-spin correlation functions, and further the dynamic critical exponents are obtained. For one-, two- and three-dimensional lattices, it is found that the dynamic critical exponents are all z = 2 if δ＞ 2, which agrees with the result when only considering nearest neighboring interactions, and that they are all δ if 0 ＜δ＜ 2. It shows that the dynamic critical exponents are independent of the spatial dimensionality but depend on the value of δ.

关键词：临界力学相位转换高斯模型自旋原子物理学

Degeneracy of holomorphic curves in surfaces

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Science China Mathematics 2005年第Z1期48卷 156-167页

作者： lIU Yuancheng ru Min Department of Mathematics University of HoustonHoustonTX 77204USA Department of MathematicsUniversity of HoustonHoustonTX 77204USA

let X be a complex projective algebraic manifold of dimension 2 and let D1,..., Du be distinct irreducible divisors on X such that no three of them share a common point. let f: C → X\(U1≤i≤uDi) be a holomorphic map. Assume that u ≥ 4 and that there exist positive integers n1,...,nu, c such that ninj(***) = c for all pairs i, j. Then f is algebraically degenerate, i.e. its image is contained in an algebraic curve on X.

关键词： degeneracy of holomorphic curves, Nevanlinna theory, complex projective surface, second main theorem.

Monte Carlo Simulations of Classical O(2) Model on Nice Tree and Bethe lattice

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Chinese Physics letters 1996年第7期13卷 496-499页

作者： GUO Wen-an YANG Zhan-ru Department of Physics and Institute of Theoretical PhysicsBeijing Normal UniversityBeijing 100875 CCAST(World laboratory) P.O.Box 8730Beijing 100080

The Metropolis Monte Carlo algorithm is applied to a classical O(2)model on nice tree and Bethe ***-size scaling theory is applied to estimate the critical *** results show that the continuous symmetry may not be spontaneously broken even if d_(f)≥d_(w)+1 where df and dw are the fractal dimension and the dimension of the random walk on the structure respectively or even if the random walk on the structure is transient.

关键词： temperature Bethe dimension

Mouse models of epithelial ovarian cancer for preclinical studies

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Zoological Research 2021年第2期42卷 153-160页

作者： Sergey Karakashev ru-Gang Zhang Immunology Microenvironment&Metastasis ProgramThe Wistar InstitutePhiladelphiaPA 19104USA

Epithelial ovarian cancer(EOC) is the leading cause of gynecological cancer-related mortality in the developed world. EOC is a heterogeneous disease represented by several histological and molecular subtypes. Therefore, exploration of relevant preclinical animal models that consider the heterogenic nature of EOC is of great importance for the development of novel therapeutic strategies that can be translated clinically to combat this devastating disease. In this review, we discuss recent progress in the development of preclinical mouse models for EOC study as well as their advantages and limitations.

关键词： Epithelial ovarian cancer Patientderived xenografts Orthotopic mouse model Subcutaneous mouse model Intraperitoneal mouse model Syngeneic mouse model Genetic engineered mouse model

Synthesis of Novel Chiral Diol ligands for the Enantioselective Reactions

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Chinese Chemical letters 2001年第6期12卷 489-490页

作者： Ming Xia lI Yan Ming WANG ru ru CHEN Research Institute of Elemento-Organic Chemistry Nankai UniversityTianjin 300071 Pittsburgh University Medical Center PittsburghPA 15213U.S.A

A series of novel enantiomerically pure diols were synthesized from D-erythorbic acid in three steps, and the absolute configuration of one of them 4a has been confirmed by X-ray analysis.

关键词： Enantiomerically pure chiral diol ligands X-ray analysis

Facile and diverse logic circuits based on dumbbell DNA-templated fluorescent copper nanoclusters and S1 nuclease detection

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Chinese Chemical letters 2022年第5期33卷 2711-2714页

作者： Zefeng Gu Anchen Fu ru Qiu ru Sun Zhijuan Cao Shanghai Key laboratory of Bioactive Small Molecules&Department of Pharmaceutical Analysis School of PharmacyFudan UniversityShanghai 201203China

DNA-based logic gates promote the development of molecular computing and show enormous potential in the fields of nanotechnology and biotechnology. Dumbbell oligonucleotides(DNA) with poly-thymine(poly-T) loops and a nicked random double strand have been demonstrated to be an efficient template for the formation of fluorescent copper nanoclusters(Cu NCs) in our previous work. Herein, a new platform technology is presented with which to construct molecular logic gates by employing Cu NCs probe as a basic output generator, coupling of functional nucleases as the inputs. Two dumbbell DNAs are used with the difference in stem length(8 bp and 16 bp, respectively). The degradation of DNA templates can be tuned by various nucleic acid enzymes, single-stranded nuclease(S1), double-stranded specific nuclease(DSN), E. coli DNA ligase, exonucleases Ⅰ and Ⅲ. Briefly, S1 can digest both DNA templates, while the cleavage ability of DSN will be resistant by the short stem of SS-DNA(short-stem DNA). Exonuclease Ⅰ and Ⅲ can degrade these two nicked DNA templates, which are inhibited due to the ligation of E. coli DNA ligase. With this novel strategy, a set of logic gates is successfully constructed at the molecular level,including “YES”, “PASS 0”, “OR”, “INHIBIT”, which take the advantages of no label, easy operation, fast speed, high efficiency and low cost. Furthermore, S1 nuclease, as the biomarker of numerous carcinogens,is selectively detected in the range of 0.05–50 U/m l with the detection limit of 0.005 U/m l(1×10^(−6)U)based on this platform.

关键词： logic gates Dumbbell DNA templates Poly-thymine loops Copper nanoclusters Nucleic acid enzymes

Helliwell-Konkowski Conjecture and the Singularities of Cauchy Horizons in 1 + 1-Dimensional Black Holes

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Chinese Physics letters 1996年第9期13卷 718-720页

作者： WANG Bin SU ru-keng Department of Physics Fudan UniversityShanghai 200433

The stability conjecture of Cauchy horizons of black holes suggested by Helliwell and Konkowski is used to investigate the 1+1-dimensional(2D)black holes under perturbations of infalling null dust and of both infalling and outgoing null *** result given by this conjecture agrees with that from mass inflation scenario for 2D charged dilaton black *** 2D black holes,we show that the Cauchy horizons are unstable and the corresponding singularities exist.

关键词： Cauchy conjecture perturbations