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1.
Danny E. Akin W. Herbert Morrison III Luanne L. Rigsby Franklin E. Barton II David S. Himmelsbach Kevin B. Hicks 《Applied biochemistry and biotechnology》2006,129(1-3):104-116
Information is presented on structure, composition, and response to enzymes of corn stover related to barriers for bioconversion
to ethanol. Aromatic compounds occurred in most tissue cell walls. Ferulic acid esterase treatment before cellulase treatment
significantly improved dry weight loss and release of phenolic acids and sugars in most fractions over cellulase alone. Leaf
fractions were considerably higher in dry weight loss and released sugars with esterase treatment, but stem pith cells gave
up the most phenolic acids. Results help identify plant fractions more appropriate for coproducts and bioconversion and those
more suitable as residues for soil erosion control. 相似文献
2.
Abe F Amidei D Apollinari G Atac M Auchincloss P Baden AR Bamberger A Barbaro-Galtieri A Barnes VE Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Bensinger J Beretvas A Berge JP Bertolucci S Bhadra S Binkley M Blair R Blocker C Booth AW Brandenburg G Brown D Buckley E Byon A Byrum KL Campagnari C Campbell M Carey R Carithers W Carlsmith D Carroll JT Cashmore R Cervelli F Chadwick K Chiarelli G Chinowsky W Cihangir S Clark AG Connor D Contreras M Cooper J Cordelli M Crane D Curatolo M 《Physical review letters》1990,65(18):2243-2246
3.
Franklin E. Schroeck Jr. 《International Journal of Theoretical Physics》1989,28(3):247-262
Recent results in the theory of integration of complex-valued functions with respect to a positive operator-valued measure are used to generalize the usual notion of coexistent observables. This leads to a connection between effects as observables and the quantization scheme of stochastic quantum mechanics. It also leads to a new viewpoint for the concept of a classical apparatus for quantum measurement which does not require a classical mechanical treatment of the apparatus from the outset. 相似文献
4.
5.
Clifford J. M. Smyth M. R. Smyth W. Franklin 《Analytical and bioanalytical chemistry》1974,270(3):198-200
Analytical and Bioanalytical Chemistry - A combination of differential solvent extraction based on physical chemical properties of the species involved and differential pulse polarography has been... 相似文献
6.
An algorithm is presented for reconstructing visible regions from visible edge segments in object space. This has applications in hidden surface algorithms operating on polyhedral scenes and in cartography. A special case of reconstruction can be formulated as a graph problem: Determine the faces of a straight-edge planar graph given in terms of its edges. This is accomplished inO(n logn) time using linear space for a graph withn edges, and is worst-case optimal. The graph may have separate components but the components must not contain each other. The general problem of reconstruction is then solved by applying our algorithm to each component in the containment relation.Research of this author is supported by the National Science Foundation under grant no. ECS-8351942, and by the Schlumberger-Doll Research Labs, Ridgefield, Connecticut. 相似文献
7.
Ssenyange S Anariba F Bocian DF McCreery RL 《Langmuir : the ACS journal of surfaces and colloids》2005,21(24):11105-11112
Various aromatic and aliphatic alkynes and one alkene were covalently bonded to sp(2)-hybridized carbon surfaces by heat treatment in an argon atmosphere. X-ray photoelectron spectroscopy, Raman, and FTIR spectra of the modified surfaces showed that the molecules were intact after the 400 degrees C heat treatment but that the alkyne group had reacted with the surface to form a covalent bond. Alkynes with ferrocene and porphyrin centers exhibited chemically reversible voltammetric waves that could be cycled many times. Atomic force microscopy of the modified surfaces indicated a thickness of the molecular layer consistent with monolayer coverage, and surface coverage determined by voltammetry was also in the monolayer range. Raman spectroscopy of the porphyrin monolayers formed from a porphyrin alkyne showed no evidence for dimer formation, although multilayer formation may occur at undetected levels. FTIR spectra of the porphyrin-modified carbon surfaces were well-defined, similar to the parent molecule, and indicative of an average tilt angle between the porphyrin plane and the surface normal of 37 degrees . The bond between the molecular monolayer and the carbon surface was quite stable, withstanding sonication in tetrahydrofuran, mild aqueous acid and base, and repeated voltammetric cycling in propylene carbonate electrolyte. Heat treatment of alkynes and alkenes appears to be a generally useful method for modifying carbon surfaces, which can be applied to both aromatic and aliphatic molecules. 相似文献
8.
Franklin Kevin R. Lowe Barrie M. 《Journal of inclusion phenomena and macrocyclic chemistry》1988,6(6):605-611
The sorption of tetraethyleneglycol by silicalite-1 and triethyleneglycol by silicalite-1 and a silicalite-1/silicalite-2 intergrowth has been studied at 25°C and at fixed water activities in the range 0.111<a
w<0.902 by an isopiestic method. All of the glycol uptakes are between 0.95 and 1.2 molecules per unit cell and in all cases they are essentially independent of water activity. The water content of the silicalite-1 was more sensitive to water activity and glycol content than was that of the silicalite-1/2 intergrowth. 相似文献
9.
A high sensitivity spectrophotometric system using a long capillary cell (LCC) detector was developed to determine dissolved inorganic phosphorus (DIP) at nanomolar concentrations in natural waters. The colorimetric chemistry used is based on the classical molybdophosphate blue technique. The radiation source is a near-infrared light-emitting diode and a silicon phototransistor is used as a detector. Method parameters were optimized for the final LCC design. With a 600-mm LCC, a detection limit (twice the standard deviation of the blank) of 1 nmol l?1 was obtained with a relative standard deviation of 6%. The working range of the instrument is 1–500 nmol l?1 DIP, and a sample volume of 10 ml is required for each analysis. The technique was applied to both fresh and marine water. The instrument is compact, relatively simple and easy to use in the laboratory and the field. 相似文献
10.
Yanyan Zhao Ole Tietz Wei-Li Kuan Abdul K. Haji-Dheere Stephen Thompson Benjamin Vallin Elisabetta Ronchi Gergely Tth David Klenerman Franklin I. Aigbirhio 《Chemical science》2020,11(18):4773
Soluble forms of aggregated tau misfolded protein, generally termed oligomers, are considered to be the most toxic species of the different assembly states that are the pathological components of neurodegenerative disorders. Therefore, a critical biomedical need exists for imaging probes that can identify and quantify them. We have designed and synthesized a novel fluorescent probe, pTP-TFE for which binding and selectivity profiles towards aggregated tau and Aβ proteins were assessed. Our results have shown pTP-TFE to be selective for early forms of soluble tau aggregates, with high affinity of dissociation constants (Kd) = 66 nM, and tenfold selectivity over mature tau fibrils. Furthermore, we found that pTP-TFE is selective for tau over Aβ aggregates and had good cell permeability. This selectivity of pTP-TFE towards early forms of aggregated tau protein ex vivo was also supported with studies on human brain tissue containing tau and Aβ pathology. To the best of our knowledge, this is the first fluorescent molecule to be reported to have this form of selectivity profile, which suggests that pTP-TFE is a unique probe candidate for imaging-based detection of early stages of Alzheimer''s disease and other tauopathies. pTP-TFE imaging probe can distinguish soluble tau aggregated proteins from other aggregated proteins enabling earlier detection of neurodegenerative diseases. 相似文献