Materials Literature
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Abstract An unsymmetrical diamine monomer 4‐( p ‐aminophenoxy)‐3‐trifluoromethyl‐4′‐aminobiphenyl has been synthesized successfully. This monomer leads to the synthesis of different novel poly(ether imide)s when reacted with different dianhydrides like pyromellatic dianhydride (PMDA), benzophenone tetracarboxylic acid…
Biomineralization produces crystals of elaborate shapes, never seen in inorganic mineralogy, with tightly regulated compositions and axis orientations. The calcite coccoliths produced by unicellular marine algae provide an example of such control at very tiny scales. Atomic force microscopy (AFM) of two species provid…
Dielectric spectroscopy of two room temperature chiral liquid crystal mixtures (W-96 and W-97) have been carried out in the frequency range of 100 mHz–10 MHz. Low frequency dielectric relaxation modes corresponding to collective behavior of molecules (Goldstone- and soft-modes) in the SmC* phase have been found to be…
Abstract The concentrations and temperatures of ultrahigh‐molecular‐weight polyethylene (UHMWPE) gel solutions exhibited a significant influence on their rheological and spinning properties. The shear viscosities of UHMWPE solutions increased consistently with increasing concentrations at a constant temperature above…
It is thought that the nuclear nonchromatin structures, such as the nuclear matrix and lamina, play regulatory roles in gene expression. In this study, we identified an insoluble protein that was associated with the chromatin-depleted nuclear structure of proliferating human leukemia HL-60 cells. Preparation of the ch…
The physical mechanism for the all-dielectric reflection gratings to achieve high efficiency in the -1st-order Littrow mounting is studied. The all-dielectric gratings consist of two parts, a surface-relief grating and a highly reflecting dielectric stack. The surface-relief grating sits on top of the reflecting stack…
Reaction equilibrium constants for the sulfate decomposition process, which releases oxygen and sulfur oxide gas in soda–lime–silica glass melts, have been determined. The chemical solubility of SO 2 , probably in the form of sulfite ions in soda–lime–silica melts, has also been determined. The chemical solubility val…
Design rules were developed for the layout of copper Damascene interconnect layers to minimize the within-die resistance variation. The impact of various layout configurations on the metal sheet resistance was characterized using two different test vehicles. An increase in resistance was observed on wide lines and hig…
The effect of the B‐site cation chemistry and ordering on the dielectric properties of solid solutions in the (1− x )Pb(Mg 1/3 Nb 2/3 )O 3 –Pb(Sc 1/2 Nb 1/2 )O 3 (PMN‐PSN) perovskite system was examined in samples with 0.1 ≤ x ≤ 0.9. Thermal annealing treatments were effective in inducing long‐range B‐site order in th…
Three-dimensional numerical simulations are performed of freckling during directional solidification of a binary metal alloy. The purpose of the study is to evaluate the sensitivity of the predictions to the grid resolution. Detailed results are provided for the liquid concentration, solid fraction, and liquid velocit…
The discharge plasma-chemical hybrid process for NO/sub x/ removal from the flue gas emissions is an extremely effective and economical approach in comparison with the conventional selective catalytic reduction system. In this paper we bring out a relative comparison of several discharge plasma reactors from the point…
Dihydroxyacetone kinases are a sequence-conserved family of enzymes, which utilize two different phosphoryldonors, ATP in animals, plants and some bacteria, and a multiphosphoprotein of the phosphoenolpyruvate carbohydrate phosphotransferase system in bacteria. Here we report the 2.5-A crystal structure of the homodim…
Compositional data and Fe 3+ /ΣFe ratios obtained by electron microprobe and Mössbauer analyses are given for a suite of three amphibole and amphibole-asbestos samples collected from the former vermiculite mine near Libby, Montana. A crystal structure analysis, compositional data, and Fe 3+ /ΣFe values for two samples…
Pure BN coatings have been synthesized on the surface of SiC powders and fibers by a novel carbothermal nitridation method. Three stages are involved in the process: first, formation of a carbon layer on the SiC by the extraction of Si with chlorine; second, infiltration of the resulting nanoporous carbide‐derived car…
Batch sorption and column breakthrough studies were conducted to investigate the potential of layered double hydroxides (LDHs) to remove bacteriophage MS2 from contaminated waters. All four of the LDHs evaluated in this study had very high retention capacities for MS2. Sorption results showed that MS2 could be complet…
We have produced an anisotropic Nd/sub 15.5/Dy/sub 1.0/Fe/sub 72.7/Co/sub 3.0/B/sub 6.8/Al/sub 1.0/ magnet by the spark plasma sintering (SPS) technique and compared it with a magnet of the same composition processed by the conventional sintering method. We investigated magnetic properties, microstructure, and constit…
A general model concerning the role of the electrode potential on the charge-transfer enhancement mechanism of SERS is proposed, justifying the existence of a parameter β which reduces the effectiveness of the electrode potential in order to shift the excited charge-transfer level. This explains the observed deviation…
Films deposited by evaporation at glancing angles form structures dependent on the speed of substrate rotation. If the substrate is held stationary, oblique columns are grown. For slow substrate rotation, helices are formed while faster rotation yields pillars. Silicon and silicon dioxide films grown under similar con…
Abstract A dinuclear peroxotungstate, K 2 [{W(O)(O 2 ) 2 (H 2 O)} 2 (μ‐O)]⋅2 H 2 O, exhibits high catalytic performance for the epoxidation of various allylic alcohols with only one equivalent of hydrogen peroxide at 305 K in water solvent. The effectiveness of this system is evidenced by high chemo‐, regio‐, and dia…
The Al 2 O 3 addition to stabilized ZrO 2 has been studied for more than 20 years. In this article, literature and new results on the positive and negative effects of Al 2 O 3 additions on the electrical properties of ZrO 2 are summarized and analyzed. In particular, a comprehensive grain‐boundary conduction model is…