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。
This paper describes electrochemical and spectroscopic properties of a well-characterized, synthetically accessible, 1.1 nm diam Au nanoparticle, Au(38)(PhC(2)S)(24), where PhC(2)S is phenylethylthiolate. Properties of other Au(38) nanoparticles made by exchanging the monolayer ligands with different thiolate ligands…
Poly(dimer acid-brassylic acid) [P(DA-BA)] copolymers and poly(dimer acid-pentadecandioic acid) [P(DA-PA)] copolymers were prepared by melt polycondensation of the corresponding mixed anhydride prepolymers. The copolymers were characterized by Fourier transform infrared (FTIR), gel permeation chromatography (GPC), dif…
Abstract The tensile stress relaxation behavior subsequent to different imposed strains of poly(1‐butene) was studied at room temperature. The plastic and elastic strains after a stress relaxation practically agree with those found for an immediate unloading. This indicates that the same decomposition of the total str…
The dielectric permittivity of the orientational glass $\mathrm{methanol}(x=0.73)\ensuremath{-}\ensuremath{\beta}$-hydroquinone-clathrate has been studied as function of temperature and waiting time using different temperature-time protocols. We study aging, rejuvenation, and memory effects in the glassy phase and dis…
Abstract A series of phosphorus‐containing dendrons is synthesized starting from a unique precursor (EtO) 2 P(O)CH=CHC 6 H 4 PPh 2 ( 3‐G 0 ), whose X‐ray crystal structure shows an extended planarity between both phosphorus. Staudinger reactions with functionalized azides on the phosphino group are the first step for…
We study the formation of engineered ferroelectric domains in two dimensions based on a continuum approach that incorporates the long-range elastic and electrostatic interactions. The model is also used to simulate the piezoelectric properties of the engineered domain configurations and the response is compared with t…
Quadrupole resonance (QR) technology for the detection of explosives is of crucial importance in an increasing number of applications. For landmine detection, where the detection system cannot be shielded, QR has proven to be highly effective if the QR sensor is not exposed to radio-frequency interference (RFI). Howev…
We present an electron energy-loss study of the nature of the low-lying singlet excitations in quasi-one-dimensional copper phthalocyanine molecular crystals. The observed variation of the spectral weight at different excitation energies strongly indicates the presence of two types of excitations near the excitation o…
We have designed, fabricated, and tested laser mirrors made entirely from porous silicon (PSi). PSi high reflectors and output couplers were designed for continuous-wave and mode-locked Ti:Sapphire lasers that were tuned between 730 nm and 940 nm. The mode-locked version of this laser produced 80 fs pulses at 85 MHz,…
Abstract The solution reaction of orotic acid (2,6‐dioxo‐1,2,3,6‐tetrahydropyrimidine‐4‐carboxylic acid, H 3 dtpc) and Ln(NO 3 ) 3 ·6H 2 O (Ln = La, Ce) or Ln 2 O 3 (Ln = Pr, Nd) yielded five complexes [{Ln( a H 2 dtpc) 2 ( b H 2 dtpc)(H 2 O) 4 }·H 2 O] n (Ln = La 1 , Ce 3 ), [La( a H 2 dtpc) 2 ( c H 2 dtpc)(H 2 O) 6…
In this study, we have extended the knowledge of the dynamics of polycarbonate (PC) far below ${T}_{g}$ by means of positron annihilation lifetime spectroscopy (PALS), which is able to detect the isothermal relaxation of the free volume after rejuvenation above ${T}_{g}.$ The free volume relaxation patterns at differe…
Abstract Various dinucleating pyrazole ligands with chelating side arms in the 3‐ and 5‐positions of the heterocycle have been shown to form Ni II /azido complexes, where the metal ions are spanned by the pyrazolate, and an azido bridge. Four new complexes have been characterized by X‐ray crystallography and variable‐…
We report on heteroepitaxial fabrication and structural characterizations of ultrafine GaN/ZnO coaxial nanorod heterostructures. The coaxial nanorod heterostructures were fabricated by epitaxial growth of a GaN layer on ultrafine ZnO nanorods. Epitaxial growth and precise control of GaN overlayer thickness were obtain…
Abstract The pyridazine‐linked cryptand L [formed by the 3+2 condensation of 3,6‐diformylpyridazine with tris(2‐aminoethyl)amine (tren)] has been used to generate a series of heterodinuclear cryptates by a one‐pot two‐step method. The cryptates [Mn II Cu I L](ClO 4 ) 2 (BF 4 ), [Fe II Cu I L](BF 4 ) 3 ·CH 3 CN and [Ni…
A new polyurethane elastomer with polyacetal soft segments (1) was synthesized by the reaction of hydroxy-terminated telechelic polyacetals (3) with an excess amount of 4,4′-diphenylmethane diisocyanate and by the subsequent chain-extension reaction with 1,4-butanediol. Polyurethane 1 exhibited good mechanical and the…
Abstract This article discusses the first part of the Brabender typical torque process curves. Rigid poly(vinyl chloride) (PVC; Polanwil S‐61) was processed at various temperatures between 160 and 200°C with blade speeds in the range of 5–40 min −1 . The morphological changes of the processed compound was characterize…
Self-assembled hexagonal Au particle networks, 2–12 μm in cell size, on silicon have been achieved by a simple method. Honeycomb structure of Au nanoparticles on silicon was drop cast from the Au nanoparticle solution under appropriate concentration, evaporation rate, substrate temperature, and humidity. Hexagonal net…
This paper investigates the behaviour of condensation in three‐layer waterproof breathable fabrics for clothing. An attempt has been made to consider water vapour transfer when condensation occurs within the three‐layer waterproof breathable fabrics based on the simultaneous heat and mass transfer theory developed by…
Based on the projector augmented-wave method, ab initio calculations confirm the ground state is of ferromagnetic bcc Fe and reveal a paramagnetic state for the hcp Fe. Interestingly, the calculations predict that there exist at least three distinct magnetic orderings for the metastable fcc structured Fe—a paramagneti…
Electroluminescent devices combining two families of PbS colloidal quantum dots to achieve spectrally tailored two-color emission are reported. Depending on device structure selected—the use of two separated layers versus a mixture of nanocrystals—the structures demonstrated light emission either in two infrared frequ…