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The self-assembly behavior of a diblock copolymer/homopolymer induced by Janus nanorods
Authors:
Y. Q. Guo,
J. Liu,
H. R. He,
N. Wu,
J. J. Zhang
Abstract:
We employ cell dynamics simulation based on the CH/BD model to investigate the self-assembly behavior of a mixed system consisting of diblock copolymers (AB), homopolymers (C), and Janus nanorods. The results indicate that, at different component ratios, the mixed system undergoes various phase transitions with an increasing number of nanorods. Specifically, when the homopolymer component is 0.40,…
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We employ cell dynamics simulation based on the CH/BD model to investigate the self-assembly behavior of a mixed system consisting of diblock copolymers (AB), homopolymers (C), and Janus nanorods. The results indicate that, at different component ratios, the mixed system undergoes various phase transitions with an increasing number of nanorods. Specifically, when the homopolymer component is 0.40, the mixed system transitions from a disordered structure to a parallel lamellar structure, subsequently to a tilted layered structure, and ultimately to a perpendicular lamellar structure as the number of nanorods increases. To explore this phenomenon in greater depth, we conduct a comprehensive analysis of domain sizes and pattern evolution. Additionally, we investigate the effects of the repulsive interaction strength between polymers, wetting strength, length of nanorods, and degree of asymmetry on the self-assembly behavior of the mixed system. This research provides significant theoretical and experimental insights for the preparation of novel nanomaterials.
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Submitted 23 September, 2025; v1 submitted 16 September, 2025;
originally announced September 2025.
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Superconductivity in iron telluride thin films under tensile stress
Authors:
Y. Han,
W. Y. Li,
L. X. Cao,
X. Y. Wang,
B. Xu,
B. R. Zhao,
Y. Q. Guo,
J. L. Yang
Abstract:
By realizing in thin films a tensile stress state, superconductivity of 13 K was introduced into FeTe, an non-superconducting parent compound of the iron pnictides and chalcogenides, with transition temperature higher than that of its superconducting isostructural counterpart FeSe. For these tensile stressed films, the superconductivity is accompanied by the softening of the first-order magnetic…
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By realizing in thin films a tensile stress state, superconductivity of 13 K was introduced into FeTe, an non-superconducting parent compound of the iron pnictides and chalcogenides, with transition temperature higher than that of its superconducting isostructural counterpart FeSe. For these tensile stressed films, the superconductivity is accompanied by the softening of the first-order magnetic and structural phase transition; and also, the in-plane extension and out-of-plane contraction are universal in all FeTe films independent of sign of lattice mismatch, either positive or negative. Moreover, the correlations were found exist between the transition temperatures and the tetrahedra bond angles in these thin films.
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Submitted 27 November, 2009;
originally announced November 2009.
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Evidence of s-wave pairing symmetry in layered superconductor Li$_{0.68}$NbO$_2$ from the specific heat measurement
Authors:
G. T. liu,
J. L. Luo,
Z. Li,
Y. Q. Guo,
N. L. Wang,
D. Jin,
T. Xiang
Abstract:
A high quality superconducting Li$_{0.68}$NbO$_2$ polycrystalline sample was synthesized by deintercalation of Li ions from Li$_{0.93}$NbO$_2$. The field dependent resistivity and specific heat were measured down to 0.5 K. The upper critical field $H_{c2} (T)$ is deduced from the resistivity data and $H_{c2}(0)$ is estimated to be $\sim 2.98$ T. A notable specific heat jump is observed at the su…
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A high quality superconducting Li$_{0.68}$NbO$_2$ polycrystalline sample was synthesized by deintercalation of Li ions from Li$_{0.93}$NbO$_2$. The field dependent resistivity and specific heat were measured down to 0.5 K. The upper critical field $H_{c2} (T)$ is deduced from the resistivity data and $H_{c2}(0)$ is estimated to be $\sim 2.98$ T. A notable specific heat jump is observed at the superconducting transition temperature $T_c \sim 5.0$ K at zero field. Below $T_c$, the electronic specific heat shows a thermal activated behavior and agrees well with the theoretical result of the BCS s-wave superconductors. It indicates that the superconducting pairing in Li$_{0.68}$NbO$_2$ has s-wave symmetry.
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Submitted 20 February, 2006;
originally announced February 2006.
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In-plane substitution effect on the magnetic properties of two-dimensional Spin-gap system SrCu$_2$(BO$_3$)$_2$
Authors:
G. T. Liu,
J. L. Luo,
Y. Q. Guo,
S. K. Su,
P. Zheng,
N. L. Wang,
D. Jin,
T. Xiang
Abstract:
A series of in-plane substituted compounds, including Cu-site (SrZn$_x$Cu$_{2-x}$(BO$_3$)$_2$), and B-site (SrCu$_2$(Si$_x$B$_{1-x}$O$_3$)$_2$) substitution, were synthesized by solid state reaction. X-ray diffraction measurements reveal that these compounds are single-phase materials and their in-plane lattice parameter depends systematically on the substituting content $x$. The magnetic suscep…
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A series of in-plane substituted compounds, including Cu-site (SrZn$_x$Cu$_{2-x}$(BO$_3$)$_2$), and B-site (SrCu$_2$(Si$_x$B$_{1-x}$O$_3$)$_2$) substitution, were synthesized by solid state reaction. X-ray diffraction measurements reveal that these compounds are single-phase materials and their in-plane lattice parameter depends systematically on the substituting content $x$. The magnetic susceptibility in different magnetic fields, the magnetization at different temperatures, and the resistivity at room temperature were measured, respectively. It is found that the spin gap deduced from the magnetic susceptibility measurements decreases with increasing of $x$ in both Cu- and B-site substitution. No superconductivity was found in these substituted compounds.
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Submitted 20 December, 2005;
originally announced December 2005.
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Physical properties, strontium ordering and structural modulation in layered hexagonal Sr0.35CoO2
Authors:
H. X. Yang,
Y. G. Shi,
Y. Q. Guo,
X. Liu,
R. J. Xiao,
J. L. Luo,
J. Q. Li
Abstract:
Layered Sr0.35CoO2 has been synthesized by means of an ion exchange reaction from Na0.7CoO2. Resistivity measurements show that this material can be either metallic or semiconducting depending on the annealing conditions. Magnetic susceptibility, following the Curie-Weiss law, increases with lowering temperature and shows a small anomalous kink at around 30 K. Transmission-electron-microscopy ob…
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Layered Sr0.35CoO2 has been synthesized by means of an ion exchange reaction from Na0.7CoO2. Resistivity measurements show that this material can be either metallic or semiconducting depending on the annealing conditions. Magnetic susceptibility, following the Curie-Weiss law, increases with lowering temperature and shows a small anomalous kink at around 30 K. Transmission-electron-microscopy observations reveal the presence of two superstructures arising respectively from the intercalated Sr-ordering (a compositional modulation) with q1 = a* / 3 + b* / 3 and a periodic structural distortion (a transverse structural modulation) with q2 = a* / 2.
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Submitted 6 March, 2005;
originally announced March 2005.