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。
The phase diagram of (PbMg 1/3 Nb 2/3 O 3 ) 1− x –(PbTiO 3 ) x (PMN–PT) has been determined to high accuracy over the whole compositional range using birefringence imaging. A steep change has been detected in the thermal hysteresis of phase transitions in the morphotropic phase boundary region at x = 0.295 at the boun…
ZnO tetrapod nanowires were fabricated by evaporation of Zn in a N 2 gas flow. Stimulated emission with a threshold of ∼ 100 μJ cm-2 was observed and the linewidths of individual modes were in the range 0.7-0.9 nm. Time-resolved measurements have been performed at different excitation powers. With an increase of the p…
The structural, magnetic and transport properties of the LaMn1−xCoxO3 system were investigated over a wide temperature range, 10–900 K. Two structural types, depending on x, were detected—orthorhombic Pbnm () and rhombohedral (x>0.6), separated by the bi-phasic sample x = 0.6. At both ends of the LaMn1−xCoxO3 system,…
Synthesis and self-assembly of nanomaterials can be controlled by the properties of soft matter. On one hand, dedicated nanoreactors such as reverse microemulsions or miniemulsions can be designed. On the other hand, direct shape control can be provided by the topology of liquid crystals that confine the reacting medi…
EuO was synthesized through the thermal reduction of Eu2O3 by a stoichiometric quantity of metallic Eu. According to the heat capacity and magnetic measurements, EuO undergoes a second-order phase transformation at ∼69K from the ferromagnetic to the paramagnetic state on heating. The magnetocaloric effect of EuO, both…
Synthesis and three-dimensional (3D) assembly of magnetite nanocrystals were realized by a one-pot procedure, in which Fe(acac)3 (acac = acetylacetonate) was partly reduced by hydrazine accompanied with ethylene glycol and spontaneously assembled into spherical nanostructures in the presence of surfactants including b…
A novel thin film of heme proteins, including hemoglobin (Hb), myoglobin (Mb), and catalase (Cat), was successfully assembled layer by layer with polyamidoamine (PAMAM) dendrimers on different solid surfaces. At pH 7.0, protonated PAMAM possesses positive surface charges, whereas the proteins have net negative surface…
Amyloid fibrils are self-associating filamentous structures, the deposition of which is considered to be one of the most important factors in the pathogenesis of Alzheimer's disease and various other disorders. Here we used single molecule manipulation methods to explore the mechanics and structural dynamics of amyloi…
Composite catalysts composed of microporous HZSM-5 and mesoporous MCM-41/SBA-15 molecular sieve materials were synthesized using the seeding method. The mesoporous materials containing pure silica and aluminum were coated on the microporous HZSM-5 zeolite. The catalytic conversion of a mixture of palm-oil-based fatty…
The unique advantage of genetic engineering techniques for the design and development of polymers for controlled gene delivery lies in exquisite control over polymer structure. In this article we report the biosynthesis and characterization of a series of new silk-elastinlike protein polymers (SELPs), namely, SELP415K…
The self-assembly in aqueous solution of hybrid block copolymers consisting of amphiphilic beta-strand peptide sequences flanked by one or two PEG chains was investigated by means of circular dichroism spectroscopy, small-angle X-ray scattering, and transmission electron microscopy. In comparison with the native pepti…
Despite considerable work in the field, the precise mechanism for the photoisomerization of azobenzene, C(12)H(10)N(2), is still an open issue. Early theoretical studies of the problem indicated that isomerization occurs through an in-plane inversion path, and this has been used to explain recent time-resolved UV-visi…
Nanoscale molecular rotors that can be driven in the solid state have been realized in Cs2([18]crown-6)3[Ni(dmit)2]2 crystals. To provide interactions between the molecular motion of the rotor and the electronic system, [Ni(dmit)2]- ions, which bear one S=1/2 spin on each molecule, were introduced into the crystal. Ro…
We performed density functional theory calculations at the PW91PW91/LANL2DZ, PW91PW91/Stuttgart 1997, PW91PW91/CRENBL, B3LYP/LANL2DZ, and SVWN5/LANL2DZ levels of theory to attain the minimum-energy structures of neutral and cationic gold clusters of up to nine gold atoms. We locate the 2D-to-3D (two-dimensional to thr…
While CNTs are found to have ultra high stiffness and strength, an enormous scatter is also observed in available laboratory results. This paper studies the effects of randomly distributed Stone Wales (SW or 5 7 7 5) defects on the mechanical properties of single walled nanotubes (SWNTs) using the technique of atomist…
A generalized Green's function theory is developed to simulate the inelastic electron tunneling spectroscopy (IETS) of molecular junctions. It has been applied to a realistic molecular junction with an octanedithiolate embedded between two gold contacts in combination with the hybrid density functional theory calculat…
The present work has demonstrated the large-capacity oxygen storage of various isomorphous lanthanide oxysulfates, Ln 2 O 2 SO 4 (Ln = La, Pr, Nd and Sm), which utilize the nonmetallic element (S) as a redox site instead of metallic cations. The reduction by H 2 or hydrocarbons and subsequent reoxidation by O 2 betwee…
Dendrimers have emerged as promising multifunctional nanomaterials for drug delivery due to their well-defined size and tailorability. We compare two schemes to obtain methylprednisolone (MP)-polyamidoamine dendrimer (PAMAM-G4-OH) conjugate. Glutaric acid (GA) was used as a spacer to facilitate the conjugation. In sch…
Long-range charge transfer excited states are notoriously badly underestimated in time-dependent density functional theory (TDDFT). We resolve how {\it exact} TDDFT captures charge transfer between open-shell species: in particular the role of the step in the ground-state potential, and the severe frequency-dependence…
Laser ablated Cr-doped SnO 2 thin films grown on various kinds of substrates all show ferromagnetism well beyond room temperature. Surprisingly, films of Sn 0.95 Cr 0.05 O 2 grown on LaAlO 3 substrates have a giant magnetic moment of 6 μ B /Cr, which is 20–30 times larger than that of films grown under the same condit…