Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
Abstract Recent advances in the study of quasicrystals (QC's) and their related materials (crystalline approximants) by using positron annihilation spectroscopy are reviewed. We describe how a series of positron annihilation spectroscopy has been applied for the studies of aperiodic QC's. Positron lifetime measurement…
Sliding wear behavior of submicrometer‐grained (grain size=0.45 μm) alumina was investigated in air and distilled water and the result was compared with the wear characteristics of similar material with coarser grain sizes. Experiments were conducted with a pin‐on‐disk wear‐testing machine under identical test conditi…
A self‐toughened gehlenite (2CaO·Al 2 O 3 ·SiO 2 or “C 2 AS”) ceramic with randomly distributed platelet grains was prepared by the organic steric entrapment (PVA) route. The gehlenite ceramic had a density of 2.698–2.875 g/cm 3 , corresponding to a relative density of 90%–96%. The platelet gehlenite grains had an ave…
We present the fabrication and transport characteristics of field-effect transistors based on single-crystalline (Ga,Mn)N nanowires with Mn concentrations of 2% and 5% prepared via a vapor−liquid−solid method. The (Ga,Mn)N nanowires with Mn concentrations of 2% and 5% configured as field-effect transistors exhibited n…
Reactions of p -sulfonatothiacalix [4]arene (Na 4 H 4 TCAS), Cu(NO 3 ) 2 ·3H 2 O, and 2,2‘-bipyridine (2,2‘-bpy) with/without silver(I) ions generated a self-complementary homometallic anionic dimer [Cu(2,2‘-bpy) 3 ][Cu 3 (HTCAS)(2,2‘-bpy) 4 ] 2 ·14H 2 O·CH 3 OH ( 1 ) and a heterometallic cluster {Ag 3 Cu 5 [H 3 (TCAS…
A quaternary compound of the composition Na 2 EuSiSe 4 featuring filled nanotubules was isolated from a reaction of elemental Eu, Si, and Se in Na 2 Se 2 flux. The compound crystallizes in the trigonal system, space group = R 3 c, a = 24.397(1), c = 7.1468(9) Å, V = 3684.2(6) Å 3 . The structure is composed of quasi-i…
A phase field model was developed to simulate hydrogen diffusion and hydrogen‐induced cracking of lead zirconate ferroelectric ceramics (PZT‐5). In this model, the evolution of hydrogen concentration around a crack in PZT was coupled with stress field analysis by solving both time‐dependent diffusion equation and time…
We study the variation in the structural and electronic properties as well as bulk modulus of perovskite-type $R{\mathrm{Rh}}_{3}{\mathrm{B}}_{x}{\mathrm{C}}_{1\ensuremath{-}x}$ with $R=\mathrm{Sc}$ and Y as a function of the boron concentration. These compounds are realized in the whole range of $0\ensuremath{\leqsla…
Periodic density functional calculations are reported for NO dissociation on the Rh(221) and RhCu(221) surfaces. The analysis of the reaction pathways indicates that the presence of steps results not only in new adsorption sites for NO adsorption but also on the appearance of a completely new reaction pathway with act…
The chemical bonding in the isostructural intermetallic compounds TiSb2 and VSb2, crystallizing in the CuAl2 type, was investigated by means of quantum chemical calculations, particularly the electron localization function (ELF), as well as by Raman spectroscopy, Hall effect and conductivity measurements on oriented s…
Surface organometallic chemistry represents an approach to the preparation of well-defined single sites for catalysis, the possibility of observing some elementary reaction steps, and the development of a fundamental basis for the synthesis of tailor-made catalysts. Silica-supported metal hydrides are an important cla…
Solid-state reactions of lanthanide(III) oxide (and/or lanthanide(III) oxychloride), MoO3 (or WO3), and TeO2 at high temperature lead to eight new luminescent compounds with four different types of structures, namely, Ln2(MoO4)(Te4O10) (Ln = Pr, Nd), La2(WO4)(Te3O7)2, Nd2W2Te2O13, and Ln5(MO4)(Te5O13)(TeO3)2Cl3 (Ln =…
Here, we report the design of a hybrid inorganic/organic mesoporous material through simultaneous pore engineering and hydrophobic surface modification of the intramesochannels to improve the uptake of superparamagnetic maghemite nanocrystals via impregnation techniques. The mesoporous material of the SBA-15 type was…
The newly synthesized 5,10,15,20-tetra[3-(3-trifluoromethyl)phenoxy]porphyrin, TTFMPP, has been characterized using mass spectroscopy, 1H-, 13C- and 19F-NMR, MALDI-TOF mass spectrometry, UV-Vis and fluorescence spectrophotometry, and cyclic voltammetry. The NMR confirmed the structure of the compound and the mass spec…
Three new chloride-rich zincophosphates including two zero-dimensional (0D) clusters [dl-Co(en)3]2[Zn4(H2PO4)2(HPO4)2Cl8] (denoted ZnPO-CJ33) and [d-Co(en)3]2[Zn4(H2PO4)2(HPO4)2Cl8] (denoted ZnPO-CJ34), and one-dimensional (1D) zincophosphate chain [dl-Co(en)3][Zn2(H2PO4)(HPO4)2Cl2] (denoted ZnPO-CJ35) have been solvo…
Liquid crystal (LC) molecules were functionalized with alkoxysilane groups and grafted on silica nanoparticles by the sol−gel process, requiring condensation of hydrolyzed molecules with silanol groups at the surface of molecules. The grafting ratio was precisely quantified from a very simple procedure using in situ r…
The preparation of two bisthiadiazinyls (7, R1 = Me, Et; R2 = Cl, R3 = Ph), the first examples of a new class of resonance-stabilized heterocyclic thiazyl radical, are reported. Both radicals have been characterized in solution by EPR spectroscopy and cyclic voltammetry, which confirm highly delocalized spin distribut…
Self-assembling cyclic D,L-peptide nanotubes are electronically insulating and possess wide band gaps (E(g) > 4 eV). Our ab initio electronic structure calculations indicate that the presence of aromatic rings in the side chain of peptide nanotubes significantly reduces the band gap. We investigate the conductivity of…
We report new polychromophoric complexes, where different porphyrin (P) derivatives are covalently coupled to a redox active Mo center, MoL*(NO)Cl(X) (L* is the face-capping tridentate ligand tris(3,5-dimethylpyrazolyl) hydroborate and X is a phenoxide/pyridyl/amido derivative of porphyrin). The luminescence quantum y…
Herein, we report on the thermal expansion and stability of V 2 AlC in the 25°–950°C temperature range. The sample was heated in an Argon atmosphere in a quartz capillary and the thermal expansion was measured using a X‐ray synchrotron radiation source. Up to the maximum temperature explored, there were no signs of de…