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61.
Broad line NMR investigations on solid L -alanine have been carried out over the temperature range 77°K to 493°K. A comparison between the observed and theoretical values of the second moment has been made, to provide check on the crystal structure and to study the molecular motions. Investigations reveal the presence of NH3 group motion at about 230°K. The activation energy for NH3 group rotation has been computed to be 7.19 ± 1.0 kcal/mole. The crystal lattice remains rigid below 230°K. There is a possibility of torsional oscillation of the CH3 group at about 352°K. 相似文献
62.
Trimethylsilyl derivatives of starch, amylose, amylopectin, and glycogen have been prepared by using hexamethyldisilazane as the silylating reagent and formamide as solvent. The degree of silylation ranged from 0.9 to 2.2 and is believed to be dependent on the structure and solubility of the polysaccharide. An important property of these trimethylsilyl derivatives is their complete solubility in common organic solvents like benzene, toluene, chloroform, etc. 相似文献
63.
Shreyasee Das Nele Dewit Dirk Jacobs Yolande A. L. Pijnenburg Sjors G. J. G. In t Veld Salom Coppens Milena Quaglia Christophe Hirtz Charlotte E. Teunissen Eugeen Vanmechelen 《International journal of molecular sciences》2022,23(13)
Neurofilament light chain (Nf-L) is a well-known biomarker for axonal damage; however, the corresponding circulating Nf-L analyte in cerebrospinal fluid (CSF) is poorly characterized. We therefore isolated new monoclonal antibodies against synthetic peptides, and these monoclonals were characterized for their specificity on brain-specific intermediate filament proteins. Two highly specific antibodies, ADx206 and ADx209, were analytically validated for CSF applications according to well-established criteria. Interestingly, using three different sources of purified Nf-L proteins, a significant impact on interpolated concentrations was observed. With a lower limit of analytical sensitivity of 100 pg/mL using bovine Nf-L as the calibrator, we were able to quantify the Nf-L analyte in each sample, and these Nf-L concentrations were highly correlated to the Uman diagnostics assay (Spearman rho = 0.97, p < 0.001). In the clinical diagnostic groups, the new Nf-L ELISA could discriminate patients with Alzheimer’s disease (AD, n = 20) from those with frontotemporal lobe dementia (FTD, n = 20) and control samples with subjective cognitive decline (SCD, n = 20). Henceforth, this novel Nf-L ELISA with well-defined specificity and epitopes can be used to enhance our understanding of harmonizing the use of Nf-L as a clinically relevant marker for neurodegeneration in CSF. 相似文献
64.
Sahu Anshuman Kumar Mahapatra Siba Sankar 《The International Journal of Advanced Manufacturing Technology》2020,107(3):1017-1023
The International Journal of Advanced Manufacturing Technology - It is of great significance for intelligent manufacturing to study condition monitoring and diagnosis methods to realize early... 相似文献
65.
Extrinsic lattice matched InAlAs/InGaAs/InP HEMT model, incorporating the parasitic source and drain resistance, for very high frequency application is developed. The current voltage characteristics and the transconductance have been evaluated and the influence of carrier concentration dependent mobility on frequency has also been analyzed. A cut-off frequency of 135 GHz is obtained. 相似文献
66.
67.
Various reaction variables in the hydrogen peroxide oxidation of starch in the presence of UV light have been investigated. Higher carboxyl and carbonyl contents of oxystarches were obtained under acidic than under alkaline conditions. Extent of oxidation was found to increase with time. Increasing the concentration of hydrogen peroxide results in an increase in the carboxyl and carbonyl contents. Apparently, air has no effect on the degree of oxidation whereas, oxygen seems to accelerate it. 相似文献
68.
An amusing anecdote that is old (having appeared in Esquire and Reader's Digest over half a century ago) concerns a man who experienced severe motion sickness during train travel whenever he would ride backwards, i.e., sat facing the rear of the train; so he learned to exchange such a seat by requesting the passenger sitting opposite to him. When he got off the train very sick and nauseated one day, his friend receiving him at the train station asked what was wrong. He replied that he had been riding the train backwards. Why didn't you ask the person sitting across from you to change seats with you? asked his friend. How could I, said the traveler, There wasn't anybody in that seat. 相似文献
69.
Subodh K. Das John A. S. Green 《JOM Journal of the Minerals, Metals and Materials Society》2010,62(2):27-31
It is now possible to assess the impact of the production processes of aluminum on the environment and to describe some of the ongoing responses and opportunities for improvement. This is compared with the benefits of aluminum in transportation, where the growing usage in various forms of transport due to its low density, high strength, and ability to be recycled enables reduced mass, increased fuel efficiency, reduced emissions and increased safety. It is the purpose of this paper to compare and contrast the emissions generated in the production of aluminum with the benefits accruing from its increased use in transportation. 相似文献
70.