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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.
S. Akin S. Isikli F. Korkusuz M. Ungan A. Senkoylu 《Journal of Radioanalytical and Nuclear Chemistry》2004,259(2):361-364
The aim of this study was to investigate the relationship between BMD and age at lumbar spine and proximal femur in Turkish
males. Two hundred ninety healthy males (aged 20-59 years) were investigated. BMD of the lumbar spine had its peak at ages
30-39, however, the peak for the proximal femur was between the ages of 20 and 29. There was a significant decrease in BMD
at proximal femur after these peak values with increasing age. In conclusion, there was a significant correlation between
age and the proximal femoral BMD in males and age has a strong predictive power on proximal femur BMD score.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
3.
We show that a theorem of Shchepin and Repovš concerning the smoothness of compacta follows from the theory of semicontinuous relations. 相似文献
4.
Briggs TF Winemiller MD Collum DB Parsons RL Davulcu AH Harris GD Fortunak JM Confalone PN 《Journal of the American Chemical Society》2004,126(17):5427-5435
The 1,2-addition of lithium phenylacetylide (PhCCLi) to quinazolinones was investigated using a combination of structural and rate studies. (6)Li, (13)C, and (19)F NMR spectroscopies show that deprotonation of quinazolinones and phenylacetylene in THF/pentane solutions with lithium hexamethyldisilazide affords a mixture of lithium quinazolinide/PhCCLi mixed dimer and mixed tetramer along with PhCCLi dimer. Although the mixed tetramer dominates at high mixed aggregate concentrations and low temperatures used for the structural studies, the mixed dimer is the dominant form at the low total mixed aggregate concentrations, high THF concentrations, and ambient temperatures used to investigate the 1,2-addition. Monitoring the reaction rates using (19)F NMR spectroscopy revealed a first-order dependence on mixed dimer, a zeroth-order dependence on THF, and a half-order dependence on the PhCCLi concentration. The rate law is consistent with the addition of a disolvated PhCCLi monomer to the mixed dimer. Investigation of the 1,2-addition of PhCCLi to an O-protected quinazolinone implicates reaction via trisolvated PhCCLi monomers. 相似文献
5.
Nihan?Kaya Erdal?Karadurmus Ahmet?AlicilarEmail author 《Central European Journal of Chemistry》2005,3(3):511-519
An attempt was made to study the oxidation of manganese by air in synthetic waters. A series of batch experments were performed
at differnet values of concentration, temperature and pH. Unoxidized manganese in the solution was determined by formaldoxime
spectrometric method. Results of these studies indicated that the air oxidation of manganese soluble in water can be effectively
performed in basic media and that oxidation yield increasedwith an increase in pH and concentration. The yield was very high
in the presence of manganese dioxide, sepiolite or clinoptilolite in solution and, the oxidation was almost completed especially
at high values of pH and concentration. The reaction was found to be first order with respect to Mn2+ with a very low activation energy. A yield of 62% was obtained for the air oxidation of wastewater taken from the treatment
plant of Corum Municipality. 相似文献
6.
The elasticity of the polyacrylamide (PAAm)-kappa carrageenan (κC) composite was determined as a function of (w/v-%) κC content at 40 °C. The gel composites studied contained various percentages (w/v-%) of κC. The elasticity of the swollen PAAm-κC composite was characterized by using the tensile testing technique. This study investigated the elasticity and the percolation threshold of PAAm-κC composite as a function of κC content. It is understood that the compressive elastic modulus decreases up to 1 (w/v-%) of κC and then increases at contents above 1(w/v-%) of κC. The critical exponent of elasticity y was determined between 1 and 1.6 (w/v-%) of κC and found to be 0.68. The observed elastic percolation threshold is consistent with the suggested values of the superelastic percolation network. 相似文献
7.
Low cost bifunctional initiators for bidirectional living cationic polymerization of olefins. I. isobutylene
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Turgut Nugay Balazs L. Keszler Tejal Deodhar Nihan Nugay Joseph P. Kennedy 《Journal of polymer science. Part A, Polymer chemistry》2017,55(22):3716-3724
We describe the discovery of novel low cost bifunctional initiators 2,4,7,9‐tetramethyl‐tricyclo[6.2.0.036]deca‐1(8),2,6‐triene‐4,9‐diol (bBCB‐diOH) and 4,9‐dichloro,2,4,7,9‐tetramethyl‐tricyclo[6.2.0.036]deca‐1(8),2,6‐triene (bBCB‐diCl), for living cationic bidirectional polymerization of olefins, for example, isobutylene. bBCB‐diOH was quantitatively synthesized in one step by UV radiation of commercially available diacetyl durene (DAD) and bBCB‐diCl by hydrochlorination of bBCB‐diOH. These molecules, in conjunction with TiCl4 coinitiator, initiate the living polymerization of isobutylene. Livingness was demonstrated by linear conversion versus molecular weight (MW) plots and narrow MW distributions. Polymerizations are slower than those initiated by the universally used “hindered” bifunctional initiator 5‐tert‐butyl‐1,3‐bis(1‐chloro‐1‐methyl)benzene and are suitable for rate studies. Herein, we report the synthesis, by the use of bBCB‐diCl, of relatively low MW (M n < 3000 g mol?1) allyl‐telechelic polyisobutylene (PIB) used for the synthesis of PIB‐based polyurethanes and that of relatively high MW (M n > 30,000) living PIB telechelics for the synthesis of thermoplastic elastomers. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 3716–3724 相似文献
8.
Dr. Celeste Are Dr. Maria Pérez Dr. Roberto Ballette Dr. Stefano Proto Dr. Federica Caso Nihan Yayik Prof. Joan Bosch Prof. Mercedes Amat 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(69):15929-15933
The synthesis of enantiopure ABCE and ABCD tetracyclic advanced intermediates en route to madangamine alkaloids and studies for the construction of the triunsaturated 15-membered D ring of madangamine B and the saturated 13-membered D ring of madangamine E are reported. 相似文献
9.
Rectangular plates on distributed elastic foundations are widely employed in footings and raft foundations of variety of structures. In particular, mounted columns and single footings may partially occupy the rectangular plate of any kind. 相似文献
10.