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1.
Amie E. Moch 《Results in Mathematics》2002,42(1-2):122-127
In this paper we determine the forcing linearity numbers for semisimple modules over integral domains. 相似文献
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[reaction: see text] The first examples of free radical-mediated vinyl amination are described by nonconventional vinyl radical addition to azomethine nitrogen. This new vinyl amination protocol is mild and provides convenient synthetic access to nonstabilized N,N-dialkyl enamines and tandem bond-forming processes. 相似文献
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Bonnie R. Hames Steven R. Thomas Amie D. Sluiter Christine J. Roth David W. Templeton 《Applied biochemistry and biotechnology》2003,105(1-3):5-16
New, rapid, and inexpensive methods that monitor the chemical composition of corn stover and corn stover-derived samples are
a key element to enabling the commercialization of processes that convert stover to fuels and chemicals. These new techniques
combine near infrared (NIR) spectroscopy and projection to latent structures (PLS) multivariate analysis to allow the compositional
analysis of hundreds of samples in 1 d at a cost of about $10 each. The new NIR/PLS rapid analysis methods can also be used
to support a variety of research projects that would have been too costly to pursue by traditional methods. 相似文献
4.
Sasithorn Uttatree Pakorn Winayanuwattikun Jittima Charoenpanich 《Applied biochemistry and biotechnology》2010,162(5):1362-1376
The benzene tolerant Acinetobacter baylyi isolated from marine sludge in Angsila, Thailand could constitutively secrete lipolytic enzymes. The enzyme was successfully
purified 21.89-fold to homogeneity by ammonium sulfate precipitation and gel-permeable column chromatography with a relative
molecular mass as 30 kDa. The enzyme expressed maximum activity at 60°C and pH 8.0 with p-nitrophenyl palmitate as a substrate and found to be stable in pH and temperature ranging from 6.0-9.0 to 60-80°C, respectively.
A study on solvent stability revealed that the enzyme was highly resisted to many organic solvents especially benzene and
isoamyl alcohol, but 40% inhibited by decane, hexane, acetonitrile, and short-chain alcohols. Lipase activity was completely
inhibited in the presence of Fe2+, Mn2+, EDTA, SDS, and Triton X-100 while it was suffered detrimentally by Tween 80. The activity was enhanced by phenylmethylsulfonyl
fluoride (PMSF), Na+, and Mg2+ and no significant effect was found in the presence of Ca2+ and Li+. Half of an activity was retained by Ba2+, Ag+, Hg+, Ni2+, Zn2+, and DTT. The enzyme could hydrolyze a wide range of p-nitrophenyl esters, but preferentially medium length acyl chains (C8-C12). Among natural oils and fats, the enzyme 11-folds favorably catalyzed the hydrolysis of rice bran oil, corn oil, sesame
oil, and coconut oil in comparison to palm oil. Moreover, the transesterification activity of palm oil to fatty acid methyl
esters (FAMEs) revealed 31.64 ± 1.58% after 48 h. The characteristics of novel A. baylyi lipase, as high temperature stability, organic solvent tolerance, and transesterification capacity from palm oil to FAMEs,
indicate that it could be a vigorous biocatalyzer in the prospective fields as bioenergy industry or even in organic synthesis
and pharmaceutical industry. 相似文献
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This review examines the most recent electrochemical developments for nitrate, nitrite and ammonium detection for on-site water monitoring. There remains a high demand for effective field-based detection of the dissolved inorganic nitrogen (DIN) analytes to aid in mitigating nitrogen loading. Electrochemical approaches show increasing potential to fill this role as advancements in nanotechnology continually improve analytical performance and on-site applicability. However, translating these improvements into the field still faces the resonating challenges of reaching analytical proficiency (selectivity, sensitivity, robustness, stability), practical end-user functionality, minimal matrix interferences and cost effectiveness. Herein, we elaborate on these challenges via a critical evaluation of current studies and examine how realistic the prospects of on-site nitrate, nitrite and ammonium are. We also present recommendations in addressing these gaps to conclude the review. 相似文献
7.
Amie K. Patchen Michael J. Pennino Annastassja C. Kiep Matthew J. Elrod 《国际化学动力学杂志》2007,39(6):353-361
A direct kinetics study of the product‐forming channels of the reaction of isoprene‐derived hydroxyalkylperoxy radicals with NO has been performed at 100 Torr pressure and 298 K using the turbulent flow technique with high‐pressure chemical ionization mass spectrometry for the detection of reactants and products. For comparative purposes, a similar study was also performed for the reaction of 1‐ and 2‐butene‐derived hydroxyalkylperoxy radicals with NO. The measured hydroxyalkylnitrate product channel branching ratios were determined to be 0.061, 0.068, and 0.070 for the 1‐butene, 2‐butene, and isoprene systems, respectively. The results are compared to previous measurements of the hydroxyalkylnitrate‐branching ratios for these systems, and the atmospheric significance of the results is discussed. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 353–361, 2007 相似文献
8.
[Structure: see text] An advanced intermediate in our planned synthesis of mitomycin C has been acquired in nine steps from tert-butyl glyoxylate. The aziridinyl pyrrolidine and quinone subunits are coupled regioselectively to arrive at an enamine that is prepared for C10 homologation. 相似文献
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