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71.
Lisa M. Goss Clay D. Mortensen Thomas A. Blake 《Journal of Molecular Spectroscopy》2004,225(2):182-188
The 770-880 cm−1 region of the methyl nitrite spectrum has been recorded at a resolution of 0.0015 cm−1 in a static cell. Consistent with published determinations of the barrier to internal rotation of the methyl group, bands belonging to the trans isomer are very congested while those belonging to the cis isomer are more tractable. A total of 634 lines have been assigned in the ν8 vibrational band of the cis isomer. These lines and 32 microwave lines have been globally fit to a Watson-type Hamiltonian with an rms deviation of 0.00044 cm−1. An additional 150 lines were also assigned but were not included in the fit because they were split by 0.001-0.005 cm−1, much larger than previously reported torsional or hyperfine splittings. 相似文献
72.
Roshmi Thomas Aswathi P. Nair Soumya KR Jyothis Mathew Radhakrishnan EK 《Applied biochemistry and biotechnology》2014,173(2):449-460
Silver nanoparticles form promising template for designing antimicrobial agents against drug resistant pathogenic microorganisms. Thus, the development of a reliable green approach for the synthesis of nanoparticles is an important aspect of current nanotechnology research. In the present investigation, silver nanoparticles synthesized by a soil Bacillus sp. were characterized using UV–vis spectroscopy, FTIR, SEM, and EDS. The antibacterial potential of biosynthesized silver nanoparticles, standard antibiotics, and their conjugates were evaluated against multidrug-resistant biofilm-forming coagulase-negative S. epidermidis strains, S. aureus, Salmonella Typhi, Salmonella Paratyphi, and V. cholerae. Interestingly, silver nanoparticles (AgNPs) showed remarkable antibacterial activity against all the test strains with the highest activity against S. epidermidis strains 145 and 152. In addition, the highest synergistic effect of AgNPs was observed with chloramphenicol against Salmonella typhi. The results of the study clearly indicate the promising biomedical applications of biosynthesized AgNPs. 相似文献
73.
Mechanically Modulating the Photophysical Properties of Fluorescent Protein Biocomposites for Ratio‐ and Intensiometric Sensors 下载免费PDF全文
Johnathan N. Brantley Constance B. Bailey Joe R. Cannon Katie A. Clark Prof. David A. Vanden Bout Prof. Jennifer S. Brodbelt Prof. Adrian T. Keatinge‐Clay Prof. Christopher W. Bielawski 《Angewandte Chemie (International ed. in English)》2014,53(20):5088-5092
Mechanically sensitive biocomposites comprised of fluorescent proteins report stress through distinct pathways. Whereas a composite containing an enhanced yellow fluorescent protein (eYFP) exhibited hypsochromic shifts in its fluorescence emission maxima following compression, a composite containing a modified green fluorescent protein (GFPuv) exhibited fluorescence quenching under the action of mechanical force. These ratio‐ and intensiometric sensors demonstrate that insights garnered from disparate fields (that is, polymer mechanochemistry and biophysics) can be harnessed to guide the rational design of new classes of biomechanophore‐containing materials. 相似文献
74.
75.
Liu T Chiang YM Somoza AD Oakley BR Wang CC 《Journal of the American Chemical Society》2011,133(34):13314-13316
An StcA-AfoE hybrid polyketide synthase (PKS), generated by swapping the AfoE (asperfuranone biosynthesis) SAT domain with the StcA (sterigmatocystin biosynthesis) SAT domian, produced a major new metabolite with the same chain length as the native AfoE product. Structure elucidation allowed us to propose a likely pathway, and feeding studies supported the hypothesis that the chain length of PKS metabolites may be under precise control of KS and PT domains. 相似文献
76.
Epoxy quinol 1a was prepared on a multi-gram scale by Noyori transfer hydrogenative desymmetrization of the readily available meso epoxy diketone 4. Although the intrinsic enantioselectivity for the desymmetrization was modest (82:18 er at 4% conversion), a highly enantiopure product (99.6:0.4 er) could be obtained in one operation in 44% yield via kinetic resolution of the minor enantiomer with long reaction times (48 h), or in 73% yield by combination with an enzymatic resolution of a 93:7 er mixture. 相似文献
77.
By a theorem of Thurston, in the subgroup of the mapping class group generated by Dehn twists around two curves which fill,
every element not conjugate to a power of one of the twists is pseudo-Anosov. We prove an analogue of this theorem for the
outer automorphism group of a free group. 相似文献
78.
79.
Ehud Ben-Hur Marian E. Clay Eduardo F. Vicioso Antonio R. Antunez Boris D. Rihter Malcolm E. Kenney Nancy L. Oleinick 《Photochemistry and photobiology》1992,55(2):231-237
When a dilute F- solution was added to a culture of Chinese hamster cells that had been preincubated with an aluminium phthalocyanine sensitizer derived from AlPcCl, the photosensitivity of the cells was markedly reduced compared to control cells not treated with F-. Under the same treatment conditions, the reduction in [3H]thymidine incorporation into cellular DNA caused by light and this sensitizer and the production of DNA-protein crosslinks caused by light and this sensitizer were also inhibited by F-. In contrast, the killing of Chinese hamster cells, the reduction of thymidine incorporation by the cells, and the production of DNA-protein crosslinks in the cells caused by the combination of light and either Photofrin II or the silicon phthalocyanine HOSiPcOSi(CH3)2(CH2)3-N(CH3)2 were not inhibited by F-. We conclude that the aluminium phthalocyanine sensitizer used is largely or completely AlPc(OH)(H2O), that it is converted to a fluoro complex by F-, and that this compound probably is a less efficient generator of photochemical damage at a critical cellular target(s) than is AlPc(OH)(H2O). The inhibition of thymidine incorporation and DNA-protein crosslink formation indicates that the effects of F- can be expressed at intracellular sites. It is further concluded that the silicon phthalocyanine sensitizer and Photofrin II do not interact significantly with F-. 相似文献
80.
James R. Clay 《BIT Numerical Mathematics》1970,10(3):249-265
In this paper we wish to show how the computer has played a valuable role in research in the theory of near-rings. Basically, the author has used the computer to generate examples of near-rings to be applied for meaningful conjectures and counter-examples. All the near-rings of order less than eight are listed in [2]. Since there is only one non-abelian group of order less than eight, it is natural to still be curious what happens when one tries to construct a near-ring from a non-abelian group. The methods used by the author to construct near-rings from groups will be illustrated on the two non-abelian groups of order 8. Specifically, for each non-abelian group of order 8, it was decided to construct all near-rings enjoying one of the following four properties:
- near-ring with identity:
- near-rings without two-sided zero;
- near-rings with no zero divisors;
- idempotent near-rings; i.e. near-rings for whichx 2=x for allx.