Read by QxMD icon Read

Attraction symmetry

Marc D Harjung, Frank Giesselmann
In thermotropic chiral Sm-A^{*} phases, an electric field along the smectic layers breaks the D_{∞} symmetry of the Sm-A^{*} phase and induces a tilt of the liquid crystal director. This so-called electroclinic effect (ECE) was first reported by Garoff and Meyer in 1977 and attracted substantial scientific and technological interest due to its linear and submicrosecond electro-optic response [S. Garoff and R. B. Meyer, Phys. Rev. A 19, 338 (1979)0556-279110.1103/PhysRevA.19.338]. We now report the observation of an ECE in the pretransitional regime from a lyotropic chiral lamellar L_{α}^{*} phase into a lyo-Sm-C^{*} phase, the lyotropic analog to the thermotropic Sm-C^{*} phase which was recently discovered by Bruckner et al...
March 2018: Physical Review. E
Manoj Kumar, Naganath G Patil, Ashootosh V Ambade, Guruswamy Kumaraswamy
Compact macromolecular dendrons have been shown to induce the formation of discontinuous inverse micellar assemblies with Fd3m symmetry in monoolein/water systems. Here, we demonstrate that a large PAMAM dendron (G5: fifth generation) induces the formation a very unusual mesophase with P4332 symmetry. This mesophase had previously been observed in monoolein/water systems only on addition of cytochrome C. The P4332 mesophase can be considered an intermediate phase between the bicontinuous Ia3d and discontinuous micellar mesophases...
May 18, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
M P Smylie, K Willa, H Claus, A E Koshelev, K W Song, W-K Kwok, Z Islam, G D Gu, J A Schneeloch, R D Zhong, U Welp
Srx Bi2 Se3 and the related compounds Cux Bi2 Se3 and Nbx Bi2 Se3 have attracted considerable interest, as these materials may be realizations of unconventional topological superconductors. Superconductivity with Tc  ~3 K in Srx Bi2 Se3 arises upon intercalation of Sr into the layered topological insulator Bi2 Se3 . Here we elucidate the anisotropy of the normal and superconducting state of Sr0.1 Bi2 Se3 with angular dependent magnetotransport and thermodynamic measurements. High resolution x-ray diffraction studies underline the high crystalline quality of the samples...
May 16, 2018: Scientific Reports
Germano Vera Cruz
The purpose of this study was to assess and compare the relative contribution of skin tone and symmetry on judgment of attractiveness regarding female faces. Two hundred and fifteen Mozambican adults were presented with a set of faces, and instructed to rate their degree of attractiveness along a continuous scale. Chi-square, factorial weight analyses and ANOVA were used to analyze the data. Face skin tone had a significant impact on the participants' attractiveness judgment of target faces. However, the target face skin tone contribution to the participants' attractiveness judgment (5% of the total variance) was much weaker than the contribution of the target face symmetry (85% of the total variance)...
April 2018: Journal of General Psychology
Xiaopeng Fan, Yuzhou Zhao, Weihao Zheng, Honglai Li, Xueping Wu, Xuelu Hu, Xuehong Zhang, Xiaoli Zhu, Qinglin Zhang, Xiao Wang, Bin Yang, Jianghua Chen, Song Jin, Anlian Pan
Two-dimensional (2D) layered metal dichalcogenides can form spiral nanostructures by a screw-dislocation-driven mechanism, which leads to changes in crystal symmetry and layer stackings that introduce attractive physical properties different from their bulk and few-layer nanostructures. However, controllable growth of spirals is challenging and their growth mechanisms are poorly understood. Here, we report the controllable growth of WS2 spiral nanoplates with different stackings by a vapor phase deposition route and investigate their formation mechanisms by combining atomic force microscopy with second harmonic generation imaging...
May 15, 2018: Nano Letters
Benaoumeur Bakhti, Divana Boukari, Michael Karbach, Philipp Maass, Gerhard Müller
We consider a lattice gas in spaces of dimensionality D=1,2,3. The particles are subject to a hardcore exclusion interaction and an attractive pair interaction that satisfies Gauss' law as do Newtonian gravity in D=3, a logarithmic potential in D=2, and a distance-independent force in D=1. Under mild additional assumptions regarding symmetry and fluctuations we investigate equilibrium states of self-gravitating material clusters, in particular radial density profiles for closed and open systems. We present exact analytic results in several instances and high-precision numerical data in others...
April 2018: Physical Review. E
Z F Wang, Zhao Liu, Jinlong Yang, Feng Liu
Coupling a quantum anomalous Hall (QAH) state with a superconducting state offers an attractive approach to detect the signature alluding to a topological superconducting state [Q. L. He et al., Science 357, 294 (2017)SCIEAS0036-807510.1126/science.aag2792], but its explanation could be clouded by disorder effects in magnetic doped QAH materials. On the other hand, an antiferromagnetic (AFM) quantum spin Hall (QSH) state is identified in the well-known high-temperature 2D superconductor of monolayer FeSe [Z...
April 13, 2018: Physical Review Letters
Kirill Plekhanov, Ivana Vasić, Alexandru Petrescu, Rajbir Nirwan, Guillaume Roux, Walter Hofstetter, Karyn Le Hur
Recently, the frustrated XY model for spins 1/2 on the honeycomb lattice has attracted a lot of attention in relation with the possibility to realize a chiral spin liquid state. This model is relevant to the physics of some quantum magnets. Using the flexibility of ultracold atom setups, we propose an alternative way to realize this model through the Mott regime of the bosonic Kane-Mele-Hubbard model. The phase diagram of this model is derived using bosonic dynamical mean-field theory. Focusing on the Mott phase, we investigate its magnetic properties as a function of frustration...
April 13, 2018: Physical Review Letters
M Kar, N B Muluk, S A Bafaqeeh, C Cingi
The lips are an essential component of the symmetry and aesthetics of the face. Cosmetic surgery to modify the lips has recently gained in popularity, but the results are in some cases disasterous. In this review, we describe the features of the ideal lips for an individual's face. The features of the ideal lips with respect to facial anatomy, important anatomical landmarks of the face, the facial proportions of the lips and ethnic and sexual differences are described. The projection and relative sizes of the upper and lower lips are as significant to lip aesthetics as the proportion of the lips to the rest of the facial structure...
February 2018: Acta Otorhinolaryngologica Italica
Xiang Lin, Shuang Lin, Yuanlan Liu, Mengmeng Gao, Haiyan Zhao, Benkang Liu, Wuliji Hasi, Li Wang
Due to their perfect geometrical symmetry, spherical metal nanoparticles have attracted much attention for various applications, including fundamental studies and construction of plasmonic devices. In this work, monodisperse silver nanospheres (Ag NSs) in aqueous solution were directly prepared by a continuous process of seed mediated growth followed by oxidative etching. Silver nanocubes (Ag NCs) were synthesized by a seed-mediated growth method and subsequently were transformed to Ag NSs by simple injection of Cu2+ to the fresh prepared Ag NCs solution...
May 10, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
Kota Mitsumoto, Hajime Yoshino
We study the orientational ordering of 2-dimensional closely packed Janus particles by extensive Monte Carlo simulations. For smaller patch sizes, the system remains in the plastic crystal phase where the rotational degrees of freedom are disordered down to the lowest temperatures. There the liquid consists of dimers and trimers of the attractive patches. For large enough patch sizes, the system exhibits a thermodynamic transition into a phase with the stripe patterns of the patches breaking the three-fold rotational symmetry...
May 4, 2018: Soft Matter
Kiran Kumar, Shin M Woo, Thomas Siu, Wilian A Cortopassi, Fernanda Duarte, Robert S Paton
We have studied the cation-π interactions of neutral aromatic ligands with the cationic amino acid residues arginine, histidine and lysine using ab initio calculations, symmetry adapted perturbation theory (SAPT), and a systematic meta-analysis of all available Protein Data Bank (PDB) X-ray structures. Quantum chemical potential energy surfaces (PES) for these interactions were obtained at the DLPNO-CCSD(T) level of theory and compared against the empirical distribution of 2012 unique protein-ligand cation-π interactions found in X-ray crystal structures...
March 14, 2018: Chemical Science
Gui-Dong Liu, Xiang Zhai, Hai-Yu Meng, Qi Lin, Yu Huang, Chu-Jun Zhao, Ling-Ling Wang
In this paper, a bulk Dirac semimetals (BDSs) based tunable narrowband absorber at terahertz frequencies is proposed and it has the attractive property of being polarization-independent at normal incidence because of its 90° rotational symmetry. Numerical results show that the absorption bandwidth is about 1.469e-2 THz and the total quality factor Q, defined as Q = f0 /Δf, reaches about 94.6, which can be attributed to the low power loss of the guided mode resonance in the dielectric layer. The simulation results are analyzed with coupled mode theory...
April 30, 2018: Optics Express
Zhizhong Zhang, Ying Wang, Bingbing Zhang, Zhihua Yang, Shilie Pan
The search of new borates with improved functional properties has attracted considerable attention. Here, a new polar fluorooxoborate, NaB4O6F (NBF) was prepared by high-temperature solid-state reaction. NBF belongs to the AB4O6F family (A = alkali metal or ammonium)-a series of compounds undergo significant cation-dependent structural changes, and NBF is of particular interest in the family due to the special cation position. Temperature-dependent ionic conductivity measurement indicates that NBF is a new solid ionic conductor, and it shows the lowest active energy of 32...
April 17, 2018: Angewandte Chemie
Sergey Lepeshov, Mingsong Wang, Alex Krasnok, Oleg Kotov, Tianyi Zhang, He Liu, Taizhi Jiang, Brian A Korgel, Mauricio Terrones, Yuebing Zheng, Andrea Alu
Two-dimensional semiconducting transition metal dichalcogenides (TMDCs) are extremely attractive materials for optoelectronic applications in the visible and near-IR range. Coupling these materials to optical nanocavities enables advanced quantum optics and nanophotonic devices. Here, we address the issue of resonance coupling in hybrid exciton-polariton structures based on single Si nanoparticles (NPs) coupled to monolayer (1L) WS2. We predict strong coupling regime with a Rabi splitting energy exceeding 110 meV for a Si NPs covered by 1L-WS2 at the magnetic optical Mie resonance due to the symmetry of the mode...
April 13, 2018: ACS Applied Materials & Interfaces
Martin Blum, Tim Ott
Symmetry is appealing, be it in architecture, art or facial expression, where symmetry is a key feature to finding someone attractive or not. Yet, asymmetries are widespread in nature, not as an erroneous deviation from the norm but as a way to adapt to the prevailing environmental conditions at a time. Asymmetries in many cases are actively selected for: they might well have increased the evolutionary fitness of a species. Even many single-celled organisms are built asymmetrically, such as the pear-shaped ciliate Paramecium, which may depend on its asymmetry to navigate towards the oxygen-richer surface of turbid waters, at least based on modeling...
April 2, 2018: Current Biology: CB
Yi Yang, Hodae Kim, Jiangping Xu, Min-Soo Hwang, Di Tian, Ke Wang, Lianbin Zhang, Yonggui Liao, Hong-Gyu Park, Gi-Ra Yi, Xiaolin Xie, Jintao Zhu
Responsive photonic crystals (PCs) have attracted much attention due to their broad applications in the field of chemical and physical sensing through varying optical properties when exposed to external stimuli. In particular, assembly of block copolymers (BCPs) has proven to be a robust platform for constructing PCs in the form of films or bulk. Here, the generation of BCPs photonic microspheres is presented with 3D periodical concentric lamellar structures through confined self-assembly. The structural color of the spherical PCs can be tuned by selective swelling of one block, yielding large change of optical property through varying both layer thickness and refraction index of the domains...
April 2, 2018: Advanced Materials
Jing-Wen Yu, Xin-Yu Wang, Chen-Yue Yuan, Wei-Zhen Li, Yu-Hao Wang, Ya-Wen Zhang
The synthesis of ultrathin metal nanosheets (NSs) attracts broad scientific and technological interest, and it still remains a challenge for non-noble metals like nickel due to their intrinsic cubic symmetry and high surface energy. Herein, we report a NiO intermediated solvothermal method towards the synthesis of ultrathin Ni NSs (thickness < 3 nm) using N,N-dimethylformamide as the solvent and n-butylamine as the shape controlling reagent. The growth of the ultrathin Ni NSs follows an intermediate mechanism which was proved by the results obtained by means of transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray absorption spectra (XAS) and X-ray photoelectron spectroscopy (XPS)...
March 29, 2018: Nanoscale
Xiaoyang Che, Boubacar Traore, Claudine Katan, Mikaël Kepenekian, Jacky Even
As a result of early theoretical predictions, evidence for the Rashba or Dresselhaus effect in hybrid perovskites has recently attracted several experimental investigations, motivated by possible applications in spin-orbitronics. For instance, a large Rashba splitting has recently been reported for the (001) surface of CH3NH3PbBr3. This effect is forbidden in the bulk material since both low-temperature and room-temperature crystal structures present inversion symmetry. Here we investigate the effects of two (001) nanoscale surface reconstructions of CH3NH3PbBr3 using first-principles approaches based on density functional theory (DFT)...
March 27, 2018: Physical Chemistry Chemical Physics: PCCP
Arpita Varadwaj, Pradeep R Varadwaj, Helder M Marques, Koichi Yamashita
This study has examined the equilibrium structure and properties of six fully or partially fluorinated hydrocarbons and several of their binary complexes using computational methods. In the monomers, the electrostatic surface potential of the fluorine is predicted to be either entirely negative or weakly positive. However, its lateral sites are always negative. This enables the fluorine to display an anisotropic distribution of charge density on its electrostatic surface. While this is the electrostatic surface scenario of the fluorine atom, the negative sites of it in some of these monomers are shown to have the potential to engage in attractive engagements with the negative site(s) on the same atom in another molecule of the same type, or a molecule of a different type, to form bimolecular complexes...
March 23, 2018: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"