Materials Literature
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The heat capacities were measured by adiabatic calorimetry down to 6 K on both the right-handed isomer and a racemic mixture of 4-(1-methylheptyloxy)-4‘-cyanobiphenyl. A thermodynamic relationship between two crystalline phases has been established and inversion between the stable and the metastable crystals has been…
The structural transformations of a MgO-attached [Ru 6 C] cluster catalyst during carbonylation under CO/H 2 and decarbonylation under vacuum were studied by energy-dispersive X-ray absorption fine structure (DXAFS). The DXAFS study revealed that the carbonylation of [Ru 6 C]/MgO to [Ru 6 C(CO) 11 ]/MgO proceeded via…
While direct laser desorption ionization of soluble polyaniline dried onto metal sample plates results in mass spectra that are similar to previously shown electrospray ionization data of similar samples, laser desorption of unsolubilized solid polyaniline results in major fragmentation of the phenyl rings. Solventles…
Contrary to the usually accepted phenomena, an optically heterogeneous 1:1 diastereomixture of DS and LS and a racemate of LS and DR obtained, respectively, from a racemic myo-inositol derivative and (S)- and racemic O-acetylmandelic acid formed stronger organogels, especially with aromatic fluids, than those formed f…
UV radiation induced graft copolymerization of methacrylic acid onto natural lignocellulose (jute) fiber was carried out both by "simultaneous irradiation and grafting" and by preirradiation methods using 1-hydroxycyclohexyl-phenyl ketone as a photoinitiator. In the "simultaneous irradiation and grafting" method, the…
Abstract Summary: In this work, we synthesized two MDI‐based polyurethanes, including a poly(ether)urethane (PEU) and a poly(carbonate)urethane (PCU), by using different soft segments, poly(tetramethylene oxide) and poly(hexyl, ethyl)carbonate diol ( $\overline M$ ∼ 2 000). We demonstrated that, in addition to the enh…
Abstract We have synthesized and characterized a variety of new amphiphilic hexakisadducts of C 60 involving mixed octahedral [5:1]‐ and [3:3]‐addition patterns. The [5:1]‐adducts 3 and 13 contain five pairs of didodecyl or diethyl malonates as non‐polar addends and, as their polar part, an extended bis(malonate) invo…
Synthetic K-rich birnessites (KBi) were prepared from the thermal decomposition of a fine-grained KMnO 4 powder heated in an air atmosphere at temperatures ranging from 200 to 1000 °C. The qualitative analysis of powder X-ray diffraction (XRD) patterns reveals a complex range of structural transformations from one met…
Using a variety of spectroscopic techniques, a number of molecular functionalities have been studied in relation to the adsorption process of proteins to air-water interfaces. While ellipsometry and drop tensiometry are used to derive information on adsorbed amount and exerted surface pressure, external reflection cir…
We investigate dynamic heterogeneities in liquid water by performing molecular dynamics simulations of the SPC/E model. We find clusters of mobile molecules. We study the temperature and time dependence of the cluster size and find that clusters grow as temperature decreases and have a maximum size at the time scale c…
Abstract This study is concerned with the temperature and molecular weight dependence of the strain‐hardening behavior of polycarbonate. It is shown that the strain‐hardening modulus reduces with increasing temperature and decreasing molecular weight. This result is interpreted in terms of temperature accelerated rela…
The structure of 3 nm ZnS nanoparticles differs from that of bulk ZnS and is shown to vary with the particle aggregation state. Dispersed or weakly aggregated nanoparticles in suspension have a more distorted internal structure than strongly aggregated nanoparticles. Reversible switching between distorted and crystall…
Single site, functionalized, single stranded (ssDNA) dendri- poly(amidoamine) (PAMAM) di-dendrons have been synthesized by covalently conjugating complementary 32 base pair oligonucleotides to single-site, thiol functionalized dendri -PAMAM di-dendrons possessing neutral or anionic surface groups. Combining these comp…
Abstract A study was made of yield and plastic flow in glassy polystyrene. A range of 12 linear atactic polystyrenes was studied: monodisperse, bimodal blends, and a polydisperse commercial sample. M n varied between 66,000 and 490,000 g/mol. These were given standardized thermal treatments and then subjected to uniax…
Cellulose constitutes an important raw material for many industries. However, the superb load-bearing properties of cellulose are accompanied by poor chemical reactivity. The hydroxyl groups on cellulose surfaces can be reacted but usually not without loss of fiber integrity and strength. Here, we describe a novel che…
Spidroins, the major silk proteins making up the spider's dragline silk, originate in two distinct tissue layers (A and B) in the spider's major ampullate gland. Formation of the complex thread from spidroins occurs in the lumen of the duct connected to the gland. Using pH-sensitive microelectrode probes, we showed th…
We report our systematic studies of the environmental effects on the photoluminescence (PL) from colloidal CdSe nanocrystals (NCs) embedded in polymer thin films. The highly luminescent bare-core CdSe NCs were significantly more robust than the core/shell CdSe/ZnS NCs against photoannealing under inert environments, w…
We compute the decoherence caused by $1/f$ fluctuations at low frequency $f$ in the critical current $I_0$ of Josephson junctions incorporated into flux, phase, charge and hybrid flux-charge superconducting quantum bits (qubits). The dephasing time $τ_ϕ$ scales as $I_0/ ΩΛS_{I_0}^{1/2}(1$ Hz$)$, where $Ω/ 2π$ is the e…
Vibrational spectra of closed shell Lennard-Jones icosahedral and cuboctahedral clusters are calculated for shell numbers between 2 and 9. Evolution of the vibrational density of states with the cluster shell number is examined and differences between icosahedral and cuboctahedral clusters described. This enabled a qu…
The formation of atomic wires via pseudomorphic step-edge decoration on vicinal silicon surfaces has been analyzed for Ga on the Si(112) surface using Scanning Tunneling Microscopy and Density Functional Theory calculations. Based on a chemical potential analysis involving more than thirty candidate structures and con…