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。
Membranen aus Gold-Nanoröhren in Polycarbonatfilmen wurden zur Untersuchung katalytischer Reaktionen an Gasflüssig-Grenzflächen verwendet, die zeigen, dass die katalytischen Eigenschaften von Gold bei der Oxidation von CO mit O2 durch Wasser verbessert und durch Erhöhung des pH-Werts der Lösung optimiert werden. Die M…
Since their discovery in 1990, the study of sp2 bonded carbon nanotubes has grown into a field of research in it's own right; however the development of the sp3 analog, diamond nanowires, has been slow. A number of theoretical models have been proposed to compare the relative stability of diamond and graphite at the n…
Poly(vinyl alcohol) (PVA) and polyamidoamine (PAMAM) dendrimers are water-soluble, biocompatible and biodegradable polymers, which have been widely applied in biomedical fields. In this paper, novel physically cross-linked hydrogels composed of PVA and amine-terminated PAMAM dendrimer G6-NH(2) were prepared by cyclic…
Abstract Natürlich vorkommende Polymere werden seit langem als Werkstoffe verwendet, wegen ihrer eingeschränkten thermoplastischen Verarbeitbarkeit jedoch nur begrenzt. In jüngerer Zeit hat die mikrobielle Synthese von Polyestern unmittelbar aus Kohlenhydraten starkes Interesse gefunden. Polymilchsäure wird auf der Ba…
Hochkristalline und monodisperse MnO- oder Mn3O4-Nanopartikel entstehen bei der thermischen Zersetzung von [Mn(acac)2] in Oleylamin in Inertatmosphäre in Gegenwart bzw. bei Abwesenheit geringer Mengen Wasser (siehe Bild). Die Teilchengröße beider Manganoxidsysteme, von der auch das magnetische Verhalten abhängt, lässt…
In this article we report the first calculations of second harmonic generation second hyperpolarizability of liquid water using coupled cluster/molecular mechanics (CC/MM) methods or coupled cluster/dielectric continuum (CC/DC) methods. The latter approach treats the solvent as an isotropic homogeneous fluid while the…
We present a novel approach to probe elastic properties of polyelectrolyte multilayer microcapsules. The method is based on measurements of the capsule load-deformation curves with the atomic force microscope. The experiment suggests that at low applied load deformations of the capsule shell are elastic. Using elastic…
β‐Glucuronidase enzymes have been attached to a porous silicon surface through a direct silicon–carbon bond based linking system (see Figure). The attached enzymes display high activity and the photoluminescent (PL) properties and surface stability of the porous silicon are retained. Quenching of the PL is observed up…
Utilizing a novel solvent of cellulose, 6 wt % NaOH/5 wt % thiourea aqueous solution, for the first time, we prepared the thermally induced cellulose gel. We investigated the thermal gelation of cellulose solutions with rheometry and the structure of the gel with 13C NMR, wide-angle X-ray diffraction, environmental sc…
A relaxing time: A dramatic increase of the energy barrier (Ueff) in tetrairon(III) single-molecule magnets can be achieved by simple chemical modification. Site-specific replacement of the six methoxide bridges in [Fe4(OMe)6(dpm)6] (Hdpm=dipivaloylmethane; Ueff/kB=3.5 K) with two tripodal 1,1,1-tris(hydroxymethyl)eth…
This Letter deals with the investigation of the electromagnetic radiation focusing using a plane-parallel plate of a material with negative real parts of the permittivity and permeability. The reasons are demonstrated for the restriction of the limiting attainable resolution of the system. The possibility of obtaining…
Abstract Due to the extensive use of water injection for oil displacement and pressure maintenance in oilfields, many reservoirs experience the problem of scale deposition when injection water starts to break through. In most cases the scaled-up wells are caused by the formation of sulfate and carbonate scales of calc…
Abstract This first in a series of articles characterized the different varieties of Indian silk for their macrostructural parameters, such as filament length, degumming loss, denier, cross section, moisture regain, and intrinsic viscosity, for example. The results of amino acid analysis using a reverse‐phase techniqu…
Membranes of gold nanotubes in polycarbonate films are used to study catalytic reactions at gas–liquid interfaces. The catalytic properties of gold for CO oxidation with O2 can be enhanced by liquid water and promoted by increasing the pH value of the solution. The membrane is sandwiched between other membranes that c…
We analyze transmission of electromagnetic waves through a periodic band-gap structure consisting of slabs of a left-handed metamaterial and air. Using the effective parameters of the metamaterial derived from its microscopic structure, we study, with the help of the transfer-matrix approach and by means of the finite…
In the framework of the perturbation theory an expression suitable for calculation of the effective conductivity of 3-D inhomogeneous metals is derived. Formally, the final expression is an exact result, however, a function written as a perturbation series enters the answer. More accurately, when statistical propertie…
Constitutive equations are developed for a polymer fluid, which is treated as a permanent network of strands bridged by junctions. The junctions are assumed to slide with respect to their reference positions under loading. Governing equations are derived by using the laws of thermodynamics under the assumption that th…
We present a detailed theoretical study of the ultrafast quasiparticle relaxation dynamics observed in normal metals and heavy fermion materials with femtosecond time-resolved optical pump-probe spectroscopy. For normal metals, a nonthermal electron distribution gives rise to a temperature (T) independent electron-pho…
Polymethacrylates with densely grafted poly-N-isopropylacrylamide side chains change their shape at the lower critical solution temperature from cylindrical brushes (left) to spherical structures (right). This is an interesting example of a temperature-induced cylinder-to-sphere transition observed for single macromol…
The universal features of quantized thermal conductance of carbon nanotubes (CNTs) are revealed through a theoretical analysis based on the Landauer theory of heat transport. The phonon-derived thermal conductance of semiconducting CNTs exhibits a universal quantization in the low-temperature limit, independent of the…