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101.
102.
Prof. Guowei Li Dr. Qun Yang Prof. Kaustuv Manna Dr. Yudi Zhang Dr. Patrick Merz Chandra Shekhar Yang Zhang Dr. Hua Lv Dr. Anastasios Markou Dr. Yan Sun Prof. Claudia Felser 《Angewandte Chemie (International ed. in English)》2023,62(27):e202303296
The study of heterogeneous reactions for enantiomeric processes based on inorganic crystals has been resurgent in recent years. However, the question remains how homochirality develops in nature and chemical reactions. Here, the successful growth of B20 group PdGa single crystals with different chiral lattices enabled us to achieve enantioselective recognition of 3,4-dihydroxyphenylalanine (DOPA) based on a new mechanism, namely orbital angular momentum (OAM) polarization. The orbital textures of PdGa crystals indicate large OAM polarization near the Fermi level and carrying opposite signs. A positive or negative magnetization in the [111] direction is expected depending on the chiral lattice of PdGa crystals. Due to this, the adsorption energies of PdGa crystals and DOPA molecules differ depending on how well the O-2p orbital of DOPA pairs with the Pd-4d orbital of PdGa. The results provide one possible explanation for how chirality arises in nature by providing an enantioselective route with pure inorganic crystals. 相似文献
103.
Piyali Bhar Farook Rahaman Tuhina Manna Ayan Banerjee 《The European Physical Journal C - Particles and Fields》2016,76(12):708
In this article, we study the possibility of sustaining static and spherically symmetric traversable wormhole geometries admitting conformal motion in Einstein gravity, which presents a more systematic approach to search a relation between matter and geometry. In wormhole physics, the presence of exotic matter is a fundamental ingredient and we show that this exotic source can be dark energy type which support the existence of wormhole spacetimes. In this work we model a wormhole supported by dark energy which admits conformal motion. We also discuss the possibility of the detection of wormholes in the outer regions of galactic halos by means of gravitational lensing. Studies of the total gravitational energy for the exotic matter inside a static wormhole configuration are also performed. 相似文献
104.
Regioselective and Stereoselective Synthesis of Pyridine‐Fused Benzoxepine Derivatives by Intramolecular Reductive Heck Cyclization [1] 下载免费PDF全文
An efficient method for the synthesis of 6,11‐dihydro[2]benzoxepino[4,3‐b]pyridine derivatives via Pd(0) catalyzed intramolecular reductive Heck cyclization is reported. The method offers the regioselective and stereoselective synthesis of highly functionalized pyridine‐fused benzoxepine derivatives in 75–85% yields under mild conditions. Chemoselective Sonogashira coupling is utilized for the synthesis of cyclization precursors. The stereochemistry of the exocyclic double bond of 6,11‐dihydro[2]benzoxepino[4,3‐b]pyridine derivatives is confirmed from single crystal X‐ray diffraction. The absence of N–Pd(II) interaction results in a reverse stereochemistry of the exocyclic double bond of dibenzoxepine derivative. 相似文献
105.
106.
Saha A Manna S Nandi AK 《Langmuir : the ACS journal of surfaces and colloids》2007,23(26):13126-13135
The riboflavin (R) and melamine (M) supramolecular complex in the mole ratio of 3:1 (RM31) produces a thermoreversible gel in aqueous medium. The gelation mechanism has been elucidated from morphological investigations using optical, electron, and atomic force microscopy together with time-dependent circular dichroism (CD) and photoluminescence (PL) spectroscopy. Optical microscopy indicates spherulitic morphology at lower gelation temperature (相似文献
107.
The propagation of bulk polaritons in ferromagnetic slab is considered through a short-wavelength approximation. Neither the damping nor the demagnetizing field do affect essentially the propagation and stability of the line soliton. The stable line soliton may be destroyed by background instability: the latter is suppressed in a narrow strip. The unstable line soliton decays into lumps, which can be described both numerically and through a variational approach. Lump interactions are mentioned. 相似文献
108.
Fabien J. T. Talbot Dr. Quentin Dherbassy Dr. Srimanta Manna Dr. Chunling Shi Shibo Zhang Dr. Gareth P. Howell Dr. Gregory J. P. Perry Prof. Dr. David J. Procter 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(46):20454-20465
Copper-catalyzed borylative multicomponent reactions (MCRs) involving olefins and C−N electrophiles are a powerful tool to rapidly build up molecular complexity. The products from these reactions contain multiple functionalities, such as amino, cyano and boronate groups, that are ubiquitous in medicinal and process chemistry programs. Copper-catalyzed MCRs are particularly attractive because they use a relatively abundant and non-toxic catalyst to selectively deliver high-value products from simple feedstocks such as olefins. In this Minireview, we explore this rapidly emerging field and survey the borylative union of allenes, dienes, styrenes and other olefins, with imines, nitriles and related C−N electrophiles. 相似文献
109.
The biased link occupation rule in the Achlioptas process (AP) discourages the large clusters from growing much ahead of others and encourages faster growth of clusters which lag behind. In this paper we propose a model where this tendency is sharply reflected in the Gamma distribution of the cluster sizes, unlike the power law distribution in AP. In this model single edges between pairs of clusters of sizes si and sj are occupied with a probability ∝(sisj)α. The parameter α is continuously tunable over the entire real axis. Numerical studies indicate that for α<αc the transition is first order, αc=0 for a square lattice and αc=−1/2 for random graphs. In the limits of α=−∞,+∞ this model coincides with models well established in the literature. 相似文献
110.