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 demonstrates that self-assembled monolayers (SAMs) formed by chemisorption of alkanethiols on the surface of obliquely deposited, 10 nm-thick, films of gold are useful in studies of the anchoring of liquid crystals (LCs) on surfaces. Self-assembled monolayers supported on obliquely deposited gold permit uni…
We have studied the ordering behavior of a (diblock copolymer, poly(styrene- d 8 )−poly(2-vinylpyridine) (dPS−PVP), in a confined geometry by neutron reflectivity, transmission electron microscopy, and atomic force microscopy. The diblock copolymer was confined between a silicon substrate (Si) on one side and a glassy…
We investigate the development of mesophase order in compositionally asymmetric (13 wt % styrene) polystyrene−polyisoprene (SI) diblock and SIS triblock copolymers. The equilibrium ordered morphology of these polymers is a body-centered-cubic (bcc) lattice of spherical S microdomains. The ordering kinetics are measure…
We present a theoretical study of polymer−polymer reaction kinetics at an interface separating two immiscible polymer phases. Such reactions are widely employed in reactive blending of incompatible species. When functional groups are weakly reactive, the rate constant k obeys mean field theory: k ∝ h, where h is the i…
Rheo-optical methods are used to examine the combined effect of shear frequency, strain amplitude, and temperature on the direction and kinetics of flow-induced alignment in lamellar block copolymers. The development of shear-induced alignment in a nearly symmetric polystyrene−polyisoprene diblock (ODT ≃ 164 °C) is re…
In this study, we report the use of surface plasmon spectroscopy (SPS) to investigate the self-assembly polymer solution adsorption process in situ . A sealed sample cell made of Teflon was assembled with the substrate initially coated with a positively charged surface using the Langmuir−Blodgett−Kuhn (LBK) deposition…
Two mixed-valence Mn(III)Mn(II) complexes and a homo-valence Mn(II) trinuclear manganese complex of stoichiometry Mn(III)Mn(II)Mn(III)(5-Cl-Hsaladhp)(2)(AcO)(4)(MeOH)(2).4CH(3)OH (1a), Mn(III)Mn(II)Mn(III) (Hsaladhp)(2)(AcO)(2)(5-Cl-Sal)(2)(thf)(2) (3a) and Mn(II)Mn(II)Mn(II) (AcO)(6)(pybim)(2) (1b) where H(3)saladhp…
This paper summarizes an extensive investigation of the thermodynamic interactions that govern phase behavior in blends of polyolefins and examines their relationship to pure component PVT properties. Interaction strengths, obtained by small-angle neutron scattering (SANS) measurements, were classified as regular or i…
A direct comparison of the self-assembly on Au and Ag of thiol and disulfide derivatives of viologens bearing long n -alkyl chains was made in order to ascertain the relative efficiency of monolayer formation for each type of functionality. The structures of the two derivatives that were studied can be written as CH 3…
The pore diameters and pore wall thicknesses of the mesoporous molecular sieves FSM-16 derived from a layered silicate (kanemite) were estimated by X-ray diffraction, physisorption, transmission electron micrographs, 29 Si MAS NMR, and modeling and simulation. The XRD simulation with a simple model of a hexagonal arra…
Assemblies of ferromagnetic cylinders made of Ni with diameters ranging from 35 to 250 nm were produced by electrodeposition in nanoporous membranes. The large coercive fields of Ni nanowires at low temperature could be accounted for by the curling mode of magnetization reversal, taking into account the distributions…
Investigations of the pore expansion in mesoporous silica in the presence of n-alkanes suggest a cooperative organization of the surfactant and alkane molecules, involving additivity of chain lengths.
Neutron reflectivity has been used to study the organization of self-assembled multilayers of sulfonated polyaniline and polyallylamine. Films were prepared by the sequential adsorption of polycations and polyanions from dilute aqueous solutions. Scattering contrast was achieved by selective deuteration of the blocks…
The effect of structure of mesogenic diacrylate monomer and temperature of photopolymerization on the morphology of polymer networks has been studied in detail. Increasing the temperature of photopolymerization increases the size of the constituent units and correspondingly the size of the pores of the polymer network…
The ground state geometry, force field, and vibrational intensity data of free-base porphine were determined by the scaled quantum mechanical (SQM) method, using a force field calculated by density functional theory. Calculations were carried out with the Becke−Lee−Yang−Paar composite exchange-correlation functional (…
The kinetics for the uptake of N 2 O 5 with NaCl [N 2 O 5 (g) + NaCl(s) → ClNO 2 (g) + NaNO 3 (s) (reaction 1)] and KBr[N 2 O 5 (g) + KBr(s) → products (reaction 6)] have been studied in a Teflon-coated Knudsen reactor. The product of reaction 1 is found to be ClNO 2, in agreement with previous studies. The only bromi…
Temperature-programmed desorption (TPD) has been used to compare the O 2 desorption characteristics of a thin film of ceria prepared by vapor deposition on an α-Al 2 O 3 (0001) substrate with that of a CeO 2 (111) surface. On CeO 2 (111), there is no substantial desorption of O 2 below ∼1300 K, while a low-temperature…
The effect of liposome composition on drug delivery to tumors and therapeutic efficacy of liposome-encapsulated anthracyclines was investigated in two murine tumor models: an ascitic tumor (J6456 lymphoma) and a solid carcinoma (M-109). Longevity in circulation correlated positively with high drug levels in the extrac…
Polymers containing in the chain backbone carbazoles substituted with two acceptor groups as nonlinear optical chromophores have been synthesized from 3,6-diformyl-9-heptylcarbazole and bis(cyanoacetate) by the Knoevenagel polycondensation. A one-stage polycondensation was carried out in tetrahydrofuran (THF) solution…
Light-induced reactions of Si surfaces with carboxylic acids to generate Si ester-modified surfaces are studied. The reaction proceeds by photoelectrochemical oxidation of porous or (100)-oriented single-crystal n-type Si in formic, acetic, or trifluoroacetic acid electrolyte solutions. The reaction products at the po…