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。
High-resolution domain studies have been performed in Pb(Zn1/3Nb2/3)O3-4.5%PbTiO3 (PZN-PT) single crystals via piezoresponse force microscopy (PFM). Irregular domain patterns with the typical sizes 20–100 nm have been observed on the (001)-oriented surfaces of unpoled samples. On the contrary, (111) crystal cuts exhib…
An important step in the synthesis of hybrid materials is the control of organic chains formation when the organically modified alkoxides are bearing polymerizable groups, such as acrylate or epoxy. Control of the process can be achieved through a deep understanding of the correlation between the synthesis parameters…
Plasma probe measurements and energy selective mass spectrometry were used to characterize the composition and energetic conditions of the ion flux of a direct current, N2/Ar, unbalanced magnetron sputtering plasma in front of a graphite target, depending on the total pressure and gas composition. It is shown that the…
We present an efficient strategy for mapping out the classical phase behavior of block copolymer systems using self-consistent-field theory. With our new algorithm, the complete solution of a classical block copolymer phase can be evaluated typically in a fraction of a second on a single-processor computer, even for h…
Polycrystalline samples of (Eu 1− x Yb x ) 2 O 3 ( x = 0.0, 0.1, 0.2, 0.5, 0.8, 0.9 and 1.0) were synthesized by a sol–gel process. X-ray diffraction data were collected and the crystal structures were refined by the Rietveld method. All samples are found to have the same crystal system and formed solid solutions over…
Tissue engineering has arisen to address the extreme shortage of tissues and organs for transplantation and repair. One of the most successful techniques has been the seeding and culturing of cells on three-dimensional biodegradable scaffolds in vitro followed by implantation in vivo ( 1 , 2 ). This technique has been…
A new approach is described for mounting microcrystals of biological macromolecules for cryocrystallography. The sample mounts are prepared by patterning thin polyimide films by standard microfabrication techniques. The patterned structures contain a small hole for the crystal connected to a larger hole via a drainage…
ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTMechanism of Structural Formation by Uniaxial Deformation in Amorphous Poly(ethylene terephthalate) above the Glass TemperatureDaisuke Kawakami, Shaofeng Ran, Christian Burger, Bruce Fu, Igors Sics, Benjamin Chu, and Benjamin S. Hsi…
As part of efforts toward developing the synthesis of novel corrole analogues, the new triazatetrabenzcorrole (TBC) phosphorus(V) compounds (BuO)8(TBC)P(OCH3)2 (3), [(BuO)8(TBC)P(OH)]+OH- (4) ((BuO)8TBC=3,6,10,13,17,20,24,27-octabutoxytriazatetrabenzcorrolate), and [(BuO)8Cl8(TBC)P(OH)]+OH- (7) ((BuO)8Cl8TBC=3,6,10,13…
We have presented systematic cross-plane thermal conductivity (λ) data for the undoped strain-symmetrized Si/Ge superlattices grown on Si(111) with superlattice (SL) period thickness varying from 3.6 to 16 nm. In thin SL period (L⩽7 nm) samples, the data have shown considerable reductions of λ, by more than 50% and 30…
A circular Dammann grating that can produce circular equal intensities at various orders in the far field is described. A set of parameters such as order, circular number, uniformity, and diffraction efficiency has been defined to describe the novel diffractive phase elements. Numerical solutions of binary-phase (0, p…
The thermal expansion of two isostructural oxides, Cu 2 O and Ag 2 O, has been measured from 10 K to their respective decomposition temperatures by means of high-resolution X-ray powder diffraction. The thermal behaviours of the two oxides are different. Cuprite has a negative thermal expansion up to about 200 K, and…
The synthesis and characterization of Pd(phen)(bdt) (1) (phen = 1,10-phenanthroline, bdt = 1,2-benzenedithiolate) is presented. 1 crystallizes in the monoclinic space group P2(1)/c, alpha = 11.281(4) A, b = 20.498(8) A, c = 8.374(3) A, beta = 90.234(8), V = 1936.5(13) A(3), Z = 4, and is isostructural with its previou…
Size dependence of the time-resolved photoluminescence (TRPL) has been investigated for the ZnO nanorods fabricated by catalyst-free metalorganic chemical vapor deposition. The nanorods have a diameter of 35 nm and lengths in the range of 150 nm to 1.1 μm. The TRPL decay rate decreases monotonically as the length of t…
The mechanism and selectivity of aromatic hydroxylation by cytochrome P450 enzymes is explored using new B3LYP density functional theory computations. The calculations, using a realistic porphyrin model system, show that rate-determining addition of compound I to an aromatic carbon atom proceeds via a transition state…
We study the temperature dependence and low and high temperature limits of the magnetic shape memory effect (MSME) in five-layered tetragonal Ni–Mn–Ga martensite. Using a simple model we show that, additionally to the limits posed by transformation to austenite or an intermartensitic transformation, the temperature de…
Electron-spin-echo experiments reveal phase-memory times as long as 58 μs at 300 K for nitrogen-vacancy centers in chemical vapor deposition (CVD) single crystals. The spins were optically polarized and optically detected. Two high-quality CVD samples were studied. From the current results, it is not clear whether the…
Recently, hybrid organic/inorganic interfaces have been used in prototype spin valves, with thin films of La0.7Sr0.3MnO3 as the spin-polarized charge carrier injecting electrode. We have used x-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy to study the surface properties of La0.7Sr0.3MnO3 t…
The effect of modulation doping by Be on the ferromagnetic properties of Ga1−xMnxAs is investigated in Ga1−xMnxAs/Ga1−yAlyAs heterojunctions and quantum wells. Introducing Be acceptors into the Ga1−yAlyAs barriers leads to an increase of the Curie temperature TC of Ga1−xMnxAs, from 70 K in undoped structures to over 1…
By constraining tethered asymmetric organometallic catalysts within the nanopores of silica supports so as to increase the interaction between the pore wall and the active center (and hence to restrict access of the reactant to the catalyst), a significant improvement in enantioselectivity is achieved. A schematic ill…