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排序方式: 共有414条查询结果,搜索用时 31 毫秒
91.
Mufasila M. Muhammed Joicy John Junais H. Mokkath 《International journal of quantum chemistry》2019,119(23):e26021
Using first-principles quantum mechanical calculations, we investigate the electric field amplification in hybrid nanostructures composed of few-atom Ni linear chains attached to an organic molecule. We found that the pristine Ni linear chains exhibit localized plasmons and produce nanoscale hotspot regions, acting as a plasmon-like nanoantenna. We demonstrate that localized plasmons provide massive electric field amplification in the vicinity of the molecule. Besides, we also investigated the active modulation of the optical absorption spectra due to the inclusion of a positive and/or negative electric field in the Hamiltonian. We believe that the results presented in this work are important for the emerging field of cavity induced photo-catalysis and will aid in the realization of new quantum nano-optic devices. 相似文献
92.
Guo-Ping Li Si-Qi Lu Xin Chen Dr. Wei-Qiang Liao Dr. Yuan-Yuan Tang Prof. Ren-Gen Xiong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(72):16625-16629
Since the first perovskite CaTiO3 was discovered in 1839, the development of perovskite has a history of 180 years. The emergence of solar cells (CH3NH3)PbI3 has set off the trend of hybrid organic–inorganic perovskite (HOIP) materials. Since then, various HOIPs have sprung up and been widely used in various material devices. Among them, HOIP ferroelectrics have gained widespread attention. However, antiperovskite, as a twin brother of perovskite, has been neglected although it has similar structure with perovskite. Here, we successfully found that [C3H7FN]3[SnCl6]Cl has a three-dimensional (3D) antiperovskite structure with the formula M3AB. Importantly, the compound exhibits obvious ferroelectric properties with an Aizu notation of 622F6 at 391 K. To the best of our knowledge, this is the first 3D hybrid organic–inorganic antiperovskite ferroelectric, which will greatly promote the development of antiperovskite families with more superior physical properties. 相似文献
93.
Herein, we report a new inorganic-organic hybrid, (H3tren)2?[Zn3(PO4)4(BDA)]?xH2O (ZnPO-BDA) prepared under hydrothermal conditions. This hybrid structure of zinc phosphate layers pillared with 4,4′-biphenyl-dicarboxylic acid (BDA) was characterized by single-crystal X-ray diffraction. The compound, ZnPO-BDA, crystallizes in the monoclinic crystal system (space group C2) with a = 14.9348(3) Å, b = 8.7058(2) Å, c = 17.6455(5) Å, β = 111.6760(10), V = 2132.02(9) Å3, Z = 2. The crystalline host of the 2D zinc phosphate framework was built with vertex linked ZnO4 and PO4 tetrahedra and anchored with tris(2-aminoethyl)amine (H3tren). Biphenyl dicarboxylic acid (BDA) molecules stack between the phosphate framework layers by means of strong hydrogen bonding, resulting in an interlayer distance of 16.4 Å. ZnPO-BDA displayed blue photoluminescence with an emission maximum at 404 nm on photoexcitation at 340 nm. 相似文献
94.
Liquid‐Crystalline Biomacromolecular Templates for the Formation of Oriented Thin‐Film Hybrids Composed of Ordered Chitin and Alkaline‐Earth Carbonate
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Dr. Tatsuya Nishimura Ken Toyoda Takahiro Ito Dr. Yuya Oaki Yukiko Namatame Prof. Takashi Kato 《化学:亚洲杂志》2015,10(11):2356-2360
Macroscopically ordered inorganic thin films have been formed on unidirectionally oriented, liquid‐crystalline chitin matrices. In the presence of poly(acrylic acid) (PAA), unidirectionally oriented chitin films act as templates for the formation of oriented thin‐film crystals of alkaline‐earth carbonates such as SrCO3 and BaCO3. The morphology and orientation of crystals are dependent on the metal ion concentration. For SrCO3 crystallization, unidirectional thin films and hexagonal‐shaped thin films have been deposited from 200 and 25 mm concentration strontium solutions, respectively. 相似文献
95.
Field polarity dependent nucleation of superconductivity in quasi-one-dimensional magnetic templates
G.W. Ataklti A.V. Silhanek J. Van de Vondel W. Gillijns A. Belkin G. Karapetrov V.V. Moshchalkov 《Physica C: Superconductivity and its Applications》2010,470(19):860-862
We investigate the nucleation of superconductivity in an Al/Al2O3/Py trilayer system by electrical transport measurements. Magnetic force microscopy images taken at room temperature show that the 0.7 μm thick Py-film form stripes of magnetic domains with alternating out-of-plane stray field. After applying a strong out of plane magnetic field H the superconductor/normal phase boundary becomes asymmetric with respect to H = 0. This lack of field polarity symmetry results from the unbalanced size distribution of domains with opposite polarity. 相似文献
96.
Organic–inorganic hybrids based on poly(butyleneadipate‐co‐terephthalate)/titanium dioxide (PBAT/TiO2) hybrid membranes were prepared via a sol–gel process. The PBAT/TiO2 hybrid membranes were prepared for various PBAT/TiO2 ratios. The resulting hybrids were characterized with a morphological structure, hydrophilicity, biodegradability, and thermal properties. The results showed that macrovoids underwent a transition into a sponge‐like membrane structure with the addition of TiO2. After sol–gel transition, a strong interaction between the inorganic network and polymeric chains led to an increase in glass transition temperature (Tg), thermal degrading temperature, and hydrophilicity, and hence a higher biodegradability. According to X‐ray diffraction measurements of the crystal structure of the hybrid, the presence of TiO2 did not change the crystal structure of PBAT. TiO2 networks are uniformly dispersed into the PBAT matrix and no aggregation of TiO2 networks in the hybrid membranes was observed through the small angle X‐ray scattering measurements. Thus, the sol–gel process of PBAT and TiO2 can be used to prepare a hybrid with higher application temperature and faster biodegradation rate. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
97.
Ying Liu Shuxia Liu Hongmei Ji Shiwei Zhang Lili Cai Ruige Cao 《Journal of Cluster Science》2009,20(3):535-543
Abstract Two organic–inorganic hybrid compounds based on the Anderson-type clusters [TeMo6O24]6−, [(H2O)2Co(TeMo6O24)][(C10N2H10)2] · 9.5H2O (1), [(C10N2H9)Ni(H2O)3]2[TeMo6O24] · 8.5H2O (2), have been synthesized by hydrothermal reactions and characterized by elemental analyses, IR spectra, thermal stability analyses,
and single-crystal X-ray diffraction. Compound 1 displays a 1D chain structure constructed from alternating [TeMo6O24]6−clusters and Co2+ along the a axis with two pendant ligands 4,4′-bpy (4,4′-bipyridine). Compound 2 is composed of [TeMo6O24]6− clusters coordinated by [Ni(bpy)(H2O)3]2+ moieties, and a supramolecular architecture is further formed through extensive hydrogen bonds interactions.
Graphical Abstract Two organic–inorganic hybrid compounds based on the Anderson-type clusters [TeMo6O24]6−and the unit [M(4,4′-bpy)] have been synthesized under the hydrothermal conditions. Compound 1 displays a 1D chain structure constructed covalently from alternating polyoxoanions [TeMo6O24]6− and Co2+ along the a axis with two pendant ligands 4,4′-bipyridine. Compound 2 is composed of [TeMo6O24]6− polyoxoanion coordinated by [Ni(bpy)(H2O)3]2+ moieties and shows a 1D chain structure through the hydrogen bonds interactions.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
98.
Summary: This work brings about the modification of sodium montmorillonite clay (MNa) by the cationic exchange with hexadecyltrimethylammonium to turn it into organophilic clay (MC16). Subsequently, MC16 was treated with silanes. Three silanes with functional groups of different chemical nature were used. The objective was to determine if the clay could affect high density polyethylene (HDPE) final behavior after being modified with each silane. The following silanes were used: Cl2Si(CH3)2, Cl2Si(CH3)(C6H5) and Cl2Si(C6H5)2. Finally, in situ hydrolysis was carried out to generate the respective siloxanes. These materials were characterized by XRD, FTIR and GPC analyses. Each one of these additives was mixed using melt compounding processing in a Haake torque rheometer Rheocord 9000 equipped with a mix chamber and roller rotors at 100 rpm and 190 °C. All hybrids were characterized by XRD, SEM and thermogravimetric analyses. Barrier properties to cyclohexane were also determined by pervaporation experiments. Results from all studies showed that the addition of approximately 3 wt% of clay has changed the macroscopic properties of the above-mentioned composites, as compared with pure HDPE. This can be explained considering the different polymer/filler interactions which take place in each system. 相似文献
99.
The reactions of two kinds of substituted 1,2,4-triazoles with BiI3 yielded three inorganic-organic hybrids: [HL1]4[Bi6I22]·[L1]4·4H2O (1) (L1=3-(1,2,4-triazole-4-yl)-1H-1,2,4-triazole); [HL2]4[Bi6I22]·6H2O (2); [HL2]2[Bi2I8]·[L2]2 (3) (L2=(m-phenol)-1,2,4-triazole). Both 1 and 2 have polynuclear anions of [Bi6I22]4- to build up the inorganic layers and substituted 1,2,4-triazoles as the organic layers. Hybrid 3 consists of two BiI5 square pyramids as inorganic layers. There exist hydrogen bondings and I?I interactions in the structures of 1, 2 and 3. Optical absorption spectra of 1, 2 and 3 reveal the presence of sharp optical gaps of 1.77, 1.77 and 2.07 eV, respectively, suggesting that these materials behave as semiconductors. 相似文献
100.
P. Judeinstein 《Journal of Sol-Gel Science and Technology》1994,2(1-3):147-151
The synthesis of polyoxometallates based macromolecules P
n (P=[SiW11O40(SiR)2]4–.4Bu4N+) presenting interesting physical properties (electrochemistry, photochemistry) is detailed. Three different paths are described, organic polymerization of monomers P (R = vinyl, allyl, methacryl, styryl), hydrosilation of monomers (R=H, R=vinyl) or direct synthesis of polymeric species. These different polymers are characterized from a multi spectroscopic study (IR, NMR), and scattering experiments (QELS, SAXS). Reaction conditions influence both the polymerization yield, the size, the structure, and the properties of these organic-inorganic hybrids. 相似文献