Materials Literature
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Three disubstituted N-confused porphyrins (2-4) were prepared in ca. 4% yield using a one-pot synthesis. These porphyrins bear 3,5-di-tert-butylphenyl groups substituted at the C(5) and C(20) meso positions and para-substituted (Br, NO(2), ethynyl) phenyl groups at the C(10) and C(15) meso positions. The specific orie…
For the control of three-way catalytic converters (TWCs), simplified models of not only the TWC but also the λ-sensors upstream and downstream of the TWC are required. The accurate interpretation of the sensor signals makes the correction or online identification of model parameters possible. Thus, a precise estimate…
A new isotactic, perfectly alternating polymer of ( S )-lactic acid and oxetane was synthesized by the entropically driven ring-opening polymerization of a 14-membered cyclic diester ( S,S - 3 ) mediated by a zinc alkoxide catalyst. The polymer ( S,S -PMOD) was characterized by NMR spectroscopy, size exclusion chromat…
[structure: see text] [structure: see text] [structure: see text] Several Precipiton phosphines were prepared and employed in the Staudinger reaction and in the reduction of secondary ozonides. Both amines and aldehdyes were obtained in good to excellent yields and purities. After use of the phosphine, isomerization a…
Hyperfine structure is observed on several infrared transitions to the 5I7 and 5I6 multiplets of the Ho3+ C4v centre in CaF2. Particularly complex and detailed hyperfine structures are observed for transitions to the Y3 level of the 5I7 multiplet, which include the appearance of ΔIz ≠ 0 transitions. The hyperfine line…
For pyrite, ${\mathrm{FeS}}_{2},$ both the imaginary and real parts of the anisotropy of the iron atomic scattering factor are experimentally determined as functions of the x-ray energy near the iron K-edge and compared with ab initio calculations. The anisotropy appears due to the deformations of the electronic state…
Abstract A study of the relaxations and the conductivity of poly(ether imide) (PEI) ULTEM 5000 was carried out. The results were compared with the ones obtained in a previous study of PEI ULTEM 1000. The glass transition temperature was determined by differential scanning calorimetry (DSC). Then, the relaxations of PE…
Static and time-resolved magneto-optical spectra of the ferromagnetic semiconductor (Ga,Mn)As show that a pulsed photoexcitation with a fluence of 10 microJ/cm(2) is equivalent to the application of an external magnetic field of about 1 mT, which relaxes with a decay time of 30 ps. This relaxation is attributed to the…
A facile method with interface assembly was developed to prepare TiO 2 /CdS composite hollow microspheres. By changing reactant concentration, stirring rate, and temperature, the hollow microspheres could be controlled in diameter, shell thickness, and composition. The morphology, structure, composition, and photolumi…
Abstract Copolymers of 2‐( o ‐chlorophenyl)‐4‐methylene‐1,3‐dioxolane with methyl methacrylate and styrene were synthesized in benzene at 85 °C in the presence of 2,2′‐azobisisobutyronitrile as initiator. The structure of the resulting copolymers was investigated and a polymerization mechanism was proposed. The intrin…
The liquid-crystal molecular order near the rubbed polymer surface is reexamined by the improved torque balance method. The surface azimuthal anchoring strength measured by the improved torque balance method is several times larger than that believed conventionally, considered to be significantly affected by the phase…
Abstract Bing cherries were coated with sodium caseinate‐ or milk protein concentrate‐based edible coatings. Besides the proteins (100 g kg −1 ), the coating formulations also included glycerol (about 300 g kg −1 protein) and either beeswax or a stearic–palmitic acid blend at a concentration of 0, 100 or 300 g lipid p…
A new synthesis of Bi(0) nanoparticles is reported. A low temperature solution phase reduction of BiCl 3 with t -BuONa activated sodium hydride at 65 °C has been successfully used to prepare large quantities of colloidal Bi(0) nanoparticles with a diameter in the range 1.8–3.0 nm. The resulting Bi nanoparticles were c…
This paper analysis and design of a wide input range DC-DC converter is proposed along with a robust power control scheme. The proposed converter and its control is designed to be compatible to a fuel cell power source, which exhibits 2:1 voltage variation as well as a slow transient response. The proposed approach co…
The morphology of thin films of Laponite (Lap) clay elaborated by the evaporation method and spin-coating technique was analyzed by atomic force microscopy and scanning electron microscopy, indicating a better quality film for the latter procedure. Rhodamine 6G (R6G) laser dye was intercalated into these films by ion…
The structure and energetics of LiBH 4 and its surfaces have been studied using the density functional theory (DFT) plane-wave method. The DFT relaxed bulk LiBH 4 structure is in agreement with the synchrotron X-ray diffraction results. Four low-index surfaces, (100), (010), (001), and (101), have been created from th…
The generalized stacking faults of Al, Pd, Pt, Ir, and Rh are investigated by a parametrized tight-binding potential. The stacking-fault energies (SFEs) are calculated to be in good agreement with experimental data, except for Al. More important, it is found that the SFE of Pt may be reduced by $14%$ by atom relaxatio…
A bicyclic trisilane unit affords all-anti peralkylated pentasilane with dihedral angles ω > 178°. Its UV and MCD spectra as well as the X-ray crystallography of a related compound demonstrate the highly σ-conjugated system due to the rigidity of the silicon chain conformation.
This paper describes a simple solution route to ZnS nanotubes assisted by CNTs and to ZnS hollow nanospheres by templating with in situ generated bubbles at low temperature. Two types of nanotube exist. One has two open ends with a very thin wall; the other has a sealed end with a thicker wall. The hollow nanospheres…
In this paper after a literature survey in which we describe previous development of the theory and the experimental work to prove the theories we discuss the so-called safety diagram and practical values of the relevant parameters in laboratory and plant equipment. We explore when operating conditions are inherently…