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。
Addition of a benzyl substituent to the macrocyclic ring of DOTA has a substantial impact on the conformational ring flipping motion of the macrocycle in the resulting LnDOTA complexes. The p-NO2-benzyl substituent in the Ln(p-NO2-Bn-DOTA)- complexes lies in an equatorial position and effectively "locks" the conformat…
Syntheses, structures, and magnetic properties of two heterobridged mu-alkoxo-mu-7-azaindolate dicopper(II) complexes, [Cu(II)2(L-F)(mu-C7H5N2)] (1) and [Cu(II)2(L-H)(mu-C7H5N2)].CH3OH (2) (H3L-F = 1,3-bis(3-fluorosalicylideneamino)-2-propanol; H3L-H = 1,3-bis(salicylideneamino)-2-propanol) have been reported. Aside f…
Abstract This article investigates the effect of moisture on the dynamic mechanical behavior of polyamide‐6 (PA6)/clay nanocomposites with dynamic mechanical analysis from −130 to 110 °C. The storage moduli increase with the clay loading for dried and moisture‐absorbed samples because of the enhancing effect from the…
In this paper, we report the use of highly electrically conductive (400−1000 S/cm) polyaniline fibers for the development of electrochemical linear actuators. The high conductivity of the fibers ensures well-defined electroactivity and actuation without a metal backing. In propylene carbonate (PC), the electrochemical…
An unusual aggregation phenomenon that involves positively charged poly(L-lysine) (PLL) and negatively charged gold nanoparticles (Au NPs) is reported. Discrete, submicrometer-sized spherical aggregates are found to form immediately upon combining a PLL solution with gold sol (diameter approximately 14 nm). These PLL-…
Antitumor activity of linear, beta-cyclodextrin polymer (CDP)-camptothecin (CPT) conjugates (HGGG6, LGGG10, HG6, and HGGG10) is investigated in nude mice bearing human LS174T colon carcinoma tumors. These conjugates differ in polymer molecular mass [97 kDa (H) or 35 kDa (L)], CDP-CPT linker structure [glycine (G) or t…
Polymerization of 1,2-dithiane (DT) and the characterization of the polymer were investigated. Bulk polymerization of DT proceeded readily without initiators above the melting point of DT, giving a polymer in high yield. The polymerization of DT was strongly affected by the presence of small amounts of thiols. The mol…
We propose the phenomenological description of ferroelectric disordering in ferroelectric-semiconductors caused by charged impurities with the charge density random fluctuations. The material improper conductivity is proportional to the averaged impurity charge density. For high enough conductivity free carriers scree…
The rheological properties of fibroin silk solutions extracted from the middle division of Bombyx mori silkworms were examined. Acidification of the solutions with acetic acid vapor gelled the material, a process which at short time scales could be reversed by exposure to ammonia vapor. The solution could also be conv…
An original preparation method, called “two solvents” method, allows the production of MnO 2 nanowires patterned by SBA-15 silicas under mild conditions, with a preserved two-dimensional hexagonal structure, a 97% filling of the porosity by oxide nanowires, and a controlled microstructure. A comparison is made with Mn…
Dielectric permittivity measurements show that (1− x )NaNbO 3 –( x )Gd 1/3 NbO 3 crystals, at x = 0.09, exhibit a first-order phase transition near 150 °C that is diffuse over a wide temperature interval. The area of the thermal hysteresis loop was found to depend both on annealing and cooling temperatures. Optical st…
Abstract A multiarm star polymer was synthesized through the grafting of oligo polyglycol with urethane chain end units onto the core of hyperbranched polyglycerol (HPG), which was obtained through the cationic ring‐opening polymerization of glycidol. Samples were characterized with 13 C NMR, liquid chromatography/mas…
Using CaCO 3 , metal oxides (all dissolved by nitric acid) and tetraethoxysilane Si(OC 2 H 5 ) 4 (TEOS) as the main starting materials, Ca 2 R 8 (SiO 4 ) 6 O 2 :A (R = Y,La,Gd;A = Eu 3+ ,Tb 3+ ) phosphor films have been dip-coated on quartz glass substrates through the sol–gel process. X-ray diffraction (XRD), atomic…
In this paper, we present an overview of recent progress in the development of the NASA Macro-Fiber Composite (MFC) piezocomposite actuator device. This will include a brief history of the development of the MFC, a description of the standard manufacturing process used to fabricate MFC actuators, and a summary of ongo…
The copper(I) bis(chelate) complex Cu(L(0))(2) has been prepared from 2,9-diphenethyl-1,10-phenanthroline and Cu(CH(3)CN)(4)BF(4). Derivative Cu(L(0))(2) has been characterized by NMR, UV-vis spectroscopy, and X-ray crystallography. Interestingly, owing to the presence of the ethylene linker, the interligand pi-pi sta…
The beta-clip fold includes a diverse group of protein domains that are unified by the presence of two characteristic waist-like constrictions, which bound a central extended region. Members of this fold include enzymes like deoxyuridine triphosphatase and the SET methylase, carbohydrate-binding domains like the fish…
Abstract In this paper, a rectangular waveguide and a nonraditive dielectric (NRD) waveguide, filled with anisotropic negative permittivity and permeability, are studied in detail. A general condition of the existence of TE and TM modes in these waveguides is derived. The unique characteristics of these waveguides are…
The ferromagnetic manganite ${\mathrm{La}}_{0.67}{\mathrm{Ca}}_{0.33}{\mathrm{MnO}}_{3}$ is systematically investigated below Curie temperature ${T}_{C}$ by measurements of internal friction ${Q}^{\ensuremath{-}1}(T),$ Young's modulus $E(T),$ resistivity $\ensuremath{\rho}(T),$ and magnetization $M(T).$ Accompanying s…
We have used spectroscopic methods to investigate the effect of cross relaxation on the 1470 and 1800 nm emissions in Tm 3+ :TeO 2 –CdCl 2 glass for Tm 3+ ion concentrations of 0.05, 0.1, 0.25, 0.5 and 1.0 mol%. The emission spectra obtained under 800 nm excitation reveal the existence of energy transfer via cross rel…
Abstract A bis(phenylamino)disulfide was prepared through the reaction of S 2 Cl 2 with aniline, and its configuration was confirmed with elemental analysis, Fourier transform infrared (FTIR), Fourier transform Raman (FT‐Raman), and 1 H NMR spectroscopy. A novel conducting polymer, poly[bis(phenylamino)disulfide] (PPA…