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。
Simulations of the solid-state structures of single-wall carbon nanotubes show that once a chiral twisting of a tube is included the interactions with the nearest tubes lock it in place. Comparison with experiments and implications for the catalytic activity of these new materials are discussed.
The experimental phase diagram of the C19H39OH–C20H41OH system has been determined and, subsequently, subjected to thermodynamic modelling. The pure components of the system are polymorphic. At low temperature they have monoclinic phases that are different: a γ phase (C2/c, Z = 8) for C20H41OH and a β phase (P21/c, Z…
We prove that the only equilibrium double bubble in <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="bold upper R squared"> <mml:semantics> <mml:msup> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mi mathvariant="bold">R</mml:mi> </mml:mrow> <mml:mn>2</mml:mn> </m…
Using in situ polarization microscopy and in situ Raman spectroscopy, a polymorphic phase transition from the triclinic to the monoclinic crystal form of 7-α-methyl-Δ5,10-norethindrone has been observed in acetone solutions at room temperature. The metastable triclinic form is nucleated epitaxially on the stable monoc…
The decomposition of CH 2 FCF 3 over some phosphate catalysts was studied. CH 2 FCF 3 began to react at 250, 300, and 450 °C over Zr 3 (PO 4 ) 4, AlPO 4, and BPO 4, respectively, and the conversion reached 100% at 475, 500, and 700 °C, respectively. The primary reaction over Zr 3 (PO 4 ) 4 was estimated to be CH 2 FCF…
The hydrothermal reaction of MoO(3) with BaH(3)IO(6) at 180 degrees C for 3 days results in the formation of Ba[(MoO(2))(6)(IO(4))(2)O(4)] x H(2)O (1). Under similar conditions, the reaction of Ba(OH)(2) x 8H(2)O with MoO(3) and Ba(IO(4))(2) x 6H(2)O yields Ba(3)[(MoO(2))(2)(IO(6))(2)] x 2H(2)O (2). The structure of 1…
Cerium oxide nanoparticles coated by cetyltrimethylammonium bromide (CTAB) were prepared using reverse micelles and microemulsion method. The as-prepared nanoparticles (25 °C) were annealed at 200, 350, 500, and 700 °C for 2 h. Their particle sizes are, respectively, 230, 50, 2, 6, and 10 nm as identified by transmiss…
Mixed Monolayer Protected Gold Clusters (MMPCs) featuring both hydrogen bonding and aromatic stacking molecular recognition functionalities have been used to create multivalent hosts for flavins. Multitopic binding of these hosts to flavin was shown to have a strong radial dependence: when the recognition site was bro…
Practical utilization of carbon nanotubes (CNTs) in nanoscale devices requires their directed placement on a substrate. Controlled placement has been achieved by a combination of the highly selective adsorption of single walled CNTs (SWNTs) onto open regions of amino-functionalized SiO 2 in a polymeric resist, followe…
The deposition of Cu at room temperature on a V 2 O 3 (0001) surface, which was prepared on a Re(0001) substrate at first, is studied by XPS (X-ray photoelectron spectroscopy), UPS (ultraviolet photoelectron spectroscopy), and LEED (low-energy-electron diffraction). The XPS results indicate that the growth of Cu follo…
An enzyme mimic consisting of pyridoxamines covalently linked to polyethyleneimine carrying long-chain alkyl groups converts pyruvic acid to dl-alanine with as much as an 8000-fold acceleration relative to the reaction with simple pyridoxamine at the same pyridoxamine concentration. The acceleration by polymer is a st…
We report on the synthesis and structure of silica-filled latex films. The main stage of the synthesis consists of physicochemical manipulations of colloidal solutions of nanosilica and nanolatex beads, followed by drying and filmification. Hence, no mechanical energy which might contribute to building or destruction…
A second-generation 1,3,5-phenylene-based dendritic porphyrin decorated with flexible alkyl chains exhibited a liquid crystallinity, and the inclusion of fullerene within the nanospace of the dendritic porphyrin strongly affected the mesophase structure in the thermotropic liquid-crystalline phase.
New resorbable and elastomeric ABA tri- and multiblock copolymers have been successfully synthesized by combining ring-opening polymerization with ring-opening polycondensation. Five different poly(L-lactide-b-1,5-dioxepan-2-one-b-L-lactide) triblock copolymers and one new poly(L-lactide-b-1,5-dioxepan-2-one) multiblo…
A new series of phthalocyanine-containing biodegradable copolymers, namely poly(phthalocyanine- co -sebacic anhydride) (Pc-SA), have been synthesized. For copolymers with a low Pc content, the Pc rings exist mainly as monomeric species in chloroform, while the aggregation of these macrocycles becomes significant as th…
Argon adsorption at 77 K on ordered mesoporous silicas (MCM-41, SBA-15) with pore diameters up to 9 nm and on disordered mesoporous silicas with larger pore sizes was investigated, allowing us to successfully develop a method to calculate pore size distributions (PSDs) for cylindrical pores with diameters below 15 nm.…
A series of asymmetric tetraarylporphyrins was synthesized from pyrrole, para-substituted oligo- or poly(ethylene glycol) monomethyl ether benzaldehyde and from 4-hydroxybenzaldehyde etherified with diethyl bromomalonate according to the Lindsey method. After hydrolysis of the tetraarylporphyrin esters, the resulting…
In this report, we present data demonstrating that cylindrical metallic particles, with various submicrometer striping patterns, may be readily distinguished in an optical microscope. Accurate particle identification is discussed relative to synthesis reproducibility and the limitations of optical microscopes. Results…
Polyelectrolyte multilayers deposited onto particles are exploited as thin films for localizing sol−gel reactions of inorganic precursors at particle surfaces, yielding core−shell colloids with defined shell thicknesses. The image shows silica colloids coated with a polyelectrolyte/titania shell.
To combine the cytotoxic activity of cisplatin and the phototoxicicity of hematoporphyrin derivatives in the same molecule, hematoporphyrin was derivatized at the two secondary alcohol positions by etherification with oligo- and poly(ethylene glycol) units. The two carboxylic acid groups of the propionate side chains…