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 iron chlorides FeCl, FeCl 2, and FeCl 3 and their ions FeCl +, FeCl 2 +, FeCl -, FeCl 2 -, and FeCl 3 - were investigated using MP2 and QCISD(T) calculations with double- and triple-ζ basis sets augmented with multiple sets of diffuse and polarization functions. The dissociation enthalpies for FeCl → Fe + Cl, FeCl…
Two tert-butyldiphenylsilyl-protected synthons 7 and 9 are prepared in excellent yields and used in a one-pot synthesis of higher generation polyether dendrons.
The redox chemistry and the changes that occurred within the solids were studied for an excessively exchanged and a nearly stoichiometric CoZSM-5 zeolite as a function of pretreatment, reduction, and reoxidation conditions. Both gravimetric and volumetric techniques were used to determine this chemistry and the stoich…
The crystallinity ( x c ) of high-pressure-crystallized poly(ethylene terephthalate) (PET), which shows values of x c ≅ 0.90 when measured by differential scanning calorimetry (DSC), was examined by means of wide-angle X-ray scattering (WAXS). PET samples crystallized under normal conditions were also investigated by…
Infrared spectroscopy measurements of the kinetics and decomposition pathways of aqueous urea ((NH 2 ) 2 CO, 200−300 °C, 275 bar) and guanidinium nitrate ([(NH 2 ) 3 C]NO 3, 240−300 °C, 275 bar) are described. A Pt/Ir alloy flow cell with diamond wafer windows was used, and heat and fluid transport models show that is…
An understanding of the molecular mechanism of muscle contraction will require a complete description of the kinetics of the myosin motor in vitro and in vivo. To this end chemical relaxation studies employing light-directed generation of ATP from caged ATP have provided detailed kinetic information in muscle fibers.…
A series of bithiophenes, disubstituted with electron donor and electron acceptor groups, have been synthesized. The electronic effects exerted by these groups, on the electrochemical oxidation potential of bithiophenes, are additive, which allows us to control the overall substituent effect and make it compatible wit…
We utilized large angle light scattering to study the structure of a sheared semidilute polymer solution. Below a critical shear rate γ̇ c we observe an enhancement of concentration fluctuations in accordance with previous experimental and theoretical work. Above γ̇ c we find dramatic changes in the transient and stea…
The visible absorption band of iodine adsorbed on zeolite blue-shifted with increasing the electropositivity of the countercation and the aluminum content in the framework. This phenomenon was attributed to the increase in the donor strength of the zeolite framework based on the analogous spectral shift of iodine in s…
The doping of silver and palladium into a 0.9Pb‐(Mg 1/3 Nb 2/3 )O 3 –0.1PbTiO 3 (PMN–PT) ceramic has been investigated. It was found that Ag could be incorporated into the PMN–PT lattice, though this was almost impossible with Pd. Doping at up to 0.2 mol% of Ag and Pd reduced the maximum dielectric constant ( K max )…
We report the synthesis and characterization of monodispersed lead sulfide (PbS) particles with diameters in the range 4−14 nm, using bicontinuous cubic phase as a matrix. It was found, through polarized optical microscopy and small-angle X-ray scattering studies, that the viscous isotropic bicontinuous cubic phase co…
The heterobimetallic cationic NLO chromophore (1-ferrocenyl-η 6 -borabenzene)(η 5 -cyclopentadienyl)cobalt(1+) ([{1-((η 5 -C 5 H 5 )Fe(η 5 -C 5 H 4 ))-η 6 -BC 5 H 5 }Co(η 5 -C 5 H 5 )] +, 1 + ) has been synthesized by reaction of FcBBr 2 and cobaltocene and subsequent oxidation with FeCl 3 . The neutral bimetallic com…
Rheological and dielectric behavior was examined for a 50 wt % solution of a symmetric styrene−isoprene−styrene (SIS) triblock copolymer ( M = 60.2K, S content = 28%) dissolved in an I-selective solvent, n -tetradecane (C14). Dynamic mechanical tests with various strain amplitudes, γ 0 = 0.03−0.8, were performed at va…
Amorphous C:D (or C:H) films were deposited on the inner surface of a spherical ultrahigh vacuum chamber by means of a direct current glow discharge in a ∼75% D2 (or H2) and ∼25% CD4 (CH4) gas mixture. Laser Raman spectroscopy analysis of the film exhibited the absence of a diamond peak at 1334.3 cm−1. The general app…
The synthesis and characterization of a series of [RTt] 2 M (RTt - = tetrakis((methylthio)methyl)borate; M = Fe, Co, Ni) complexes are reported. Isostructural derivatives of the newly synthesized phenyltris((methylthio)methyl)borate (PhTt - ) also have been prepared and characterized. In each case, the ligand provides…
EPR and FTIR have been used to obtain information on the oxygen adsorption sites generated on CeO2/γ-Al2O3 samples by outgassing treatments at different temperatures. Several types of O2– species, showing EPR signals with different line shapes, have been detected depending on the type of surface sites where the radica…
Two ruthenium nitrosyl porphyrins have been synthesized and characterized by spectroscopic and electrochemical methods. The investigated compounds are represented as [(TPP)Ru(NO)(H(2)O)]BF(4) and (TPP)Ru(NO)(ONO) where TPP is the dianion of 5,10,15,20-tetraphenylporphyrin. (TPP)Ru(NO)(ONO) crystallizes in the tetragon…
Two new nickel(II) bridging-cyanate complexes of formula [{Ni(323-tet)(µ-OCN)}n][ClO4]n1[323-tet =N,N′-bis(3-aminopropyl)ethane-1,2-diamine] and [{Ni(Me6[14]aneN4)}2(µ-OCN)2][ClO4]22(Me6[14]aneN4=DL-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) have been synthesized and characterized. The crystal struct…
Phosphorus-containing dendrimers 1-[G'(1)]-1-[G'(4)] (generation 1 to generation 4) possessing terminal aldehyde groups reacted with a variety of hydrazino compounds. Addition of hydrazine itself to 1-[G'(1)]-1-[G'(4)] afforded the corresponding dendrimers 2-[G(1)]-2-[G(4)] with hydrazono groups at the periphery. Addi…
Both the 77 K single crystal absorption and 20 K emission spectrum of (&mgr;-1,1-dicyanoethylene-2,2-dithiolato-S,S')bis(triphenylphosphine)digold(I), (AuPPh(3))(2)[i-MNT], show resolved vibronic structure. Progressions in the 1410 cm(-)(1) C=C stretching mode of the dithiolate ligand, and in the 480 cm(-)(1) mode, wh…