Materials Literature
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The beta-glucosidase encoded by the bglA gene from Bacillus polymyxa was overproduced in Escherichia coli by using a plasmid in which bglA is under control of the lacI promoter. Induction with isopropyl-beta-D-thiogalactopyranoside allowed an increase in the specific activity of the enzyme of about 100 times the basal…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHIV inhibitory natural products. 6. The peltatols, novel HIV-inhibitory catechol derivatives from Pothomorphe peltataKirk R. Gustafson, John H. Cardellina II, James B. McMahon, Lewis K. Pannell, Gordon M. Cragg, and Michael R. BoydCite this: J. Org. Chem. 1992, 57, 10, 2809–…
Nonstoichiometric, anhydrous thin films were produced by sputtering. They can be bleached by means of hydrogen insertion equally fast and efficiently either in an electrochemical cell or in a gas chamber, as demonstrated in this work by using a Pd covered thin film electrode. The electrode mechanical stress and transm…
The adsorption mode of two highly purified cellulases, exo- and endo-type cellulases, from Irpex lacteus (Polyporus tulipiferae) was investigated by using pure cellulosic materials with different crystallinity as substrates. Adsorption of the two enzymes on the substrates was found to fit the Langmuir-type adsorption…
Using ac conductivity and the concentration cell emf method, conductivity contributions from protons, native ions, and electrons have been measured as a function of temperature (560° to 1156°C) in wet oxygen/air for the cubic systems Y 2 O 3 + 1 mol% MgO, Sm 2 O 3 + 1 mol% CaO, Gd 2 O 3 + 1 mol% CaO, and YYbO 3 + 5 mo…
The kraft pulp and paper industry is currently faced with the challenge of substantially reducing the discharge of conventional and toxic pollutants to the receiving environment without compromising its competitiveness. Ultrafiltration (UF) and nanofiltration (NF) are among the various unit processes that are being in…
Hybrid refractive-diffractive elements offer a similar level of aberration control to the conventional doublet with approximately half the volume of material. The design principles of infrared elements are discussed. It is shown that, in order to match the performance of the conventional doublet, a general meniscus hy…
The sintering sequence of Y 2 O 3 ‐Al 2 O 3 ‐doped Si 3 N 4 was investigated with respect to the relationship between densification, α→β transformation, and microstructural development. Quenching studies were performed to reveal these interactions during a complete sintering cycle. Isothermal studies were conducted to…
A pure, acicular lead titanate (PbTiO 3 ) fine powder with a white color has been prepared by hydrothermal synthesis. It is a new phase of PbTiO 3 with I 4 symmetry, cell parameters of a = 12.358 Å and b = 14.541 Å, and a density of 6.80 g.cm −3 . The influences of pH (12.5 to 14.4), Pb/Ti ratio (1.0 to 1.6) in the fe…
New satellite features and antiholes in the persistent hole-burning spectrum of N–V centers in diamond, as well as their dependences on applied electric fields and frequency within the inhomogeneous absorption line, are reported. These results, together with reassignments of spin states of this center, permit an under…
Thermodynamic miscibility in high polymer mixtures is almost always the result of specific interactions between the components. However, there are a few blends which exhibit miscibility apparently without any specific
Abstract Previously measured decay rates of HNO in the presence of NO have been kinetically modeled on the basis of thermochemical data calculated with the BAC‐MP4 technique. The results of this modeling, aided by TST‐RRKM calculations for the association of HNO and the isomerization, decomposition, and stabilization…
In thin-film directional solidification of the ${\mathrm{CBr}}_{4}$-${\mathrm{C}}_{2}$${\mathrm{Cl}}_{6}$ eutectic alloy, we observe a quasi-instantaneous transition from symmetric states to drifting parity-broken (``tilted'') states as a result of a sudden increase of the pulling velocity. We show that (i) the observ…
Abstract The accuracy of quantified XPS/AES compositions for a given sample depends on both systematic and random errors. Parameters such as escape depths, transmission functions, sensitivity factors and whether the model of the surface physical structure used in the quantification procedure is appropriate contribute…
We suggest that crystals, when introduced into an organism, may behave as conventional antigens, mediating the production of specific antibodies. These antibodies would bear an imprint of the crystal surface and may consequently behave as a nucleating matrix in a new crystallization event. Thus, they would behave as c…
Flanked by [PW 9 O 34 ] and [WO 6 ] units , the Ni cluster in the salt 1 is magnetically isolated. Within this triangulo Ni cluster, however, ferromagnetic exchange interactions take place. According to magnetic measurements μ eff increases with decreasing temperature to a value of 8.1 μ B mol −1 at 5 K, supporting a…
Abstract Reaction of 1,3-bis(salicylideneamino)-2-propanol (H3L) with manganese(II) acetate tetrahydrate in the presence of ethylenediamine and sodium thiocyanate give a salen complex [Mn(salen)(NCS)] (H2salen = N,N′-disalicylideneethylenediamine), while that in the presence of water and triethylamine gives a binulear…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTwo unique pentacyclic steroids with cis C/D ring junction from Xestospongia bergquistia Fromont, powerful inhibitors of histamine releaseNoboru Shoji, Akemi Umeyama, Kogyoku Shin, Katsuko Takeda, Shigenobu Arihara, Junichi Kobayashi, and Masao TakeiCite this: J. Org. Chem.…
The diatom stratigraphy of Holocene sediment cores from an Antarctic lake (S 67° 48′40″, W 67° 18′50″) on Horseshoe Island has been investigated. The diatom analyses show evidence of a transition from a marine to a brackish to a fresh water environment. The diatom stratigraphy is divided into three different assemblag…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEnantioselective complexation of organic ammonium ions by simple tetracyclic podand ionophoresXuebao Wang, Shawn D. Erickson, Takamasa Iimori, and W. Clark StillCite this: J. Am. Chem. Soc. 1992, 114, 11, 4128–4137Publication Date (Print):May 1, 1992Publication History Publi…