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11.
Alam MS Katayama N Kim IJ Li WC Lou XC Sun CR Bortoletto D Goldberg M Horwitz N Mestayer MD Moneti GC Sharma V Shipsey IP Skwarnicki T Csorna SE Letson T Brock IC Ferguson T Artuso M Bebek C Berkelman K Blucher E Byrd J Cassel DG Cheu E Coffman DM Crawford G DeSalvo R DeWire JW Drell PS Ehrlich R Galik RS Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Kandaswamy J Kowalewski R Kreinick DL Kubota Y Lewis JD Mistry NB Mueller J Namjoshi R Nandi S Nordberg E O'Grady C Peterson D Pisharody M 《Physical review D: Particles and fields》1989,40(11):3790
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Gert E. V. Zubets O. V. Shishonok M. V. Torgashov V. I. Kaputskii F. N. 《Russian Journal of Applied Chemistry》2003,76(4):595-599
The capability of cotton and wood cellulose in the common and microcrystalline forms to transform into cellulose-II under the action of 68-69% HNO3 was studied. The influence of temperature on the course of the phase transition in cellulose samples differing in origin and morphological structure and the dynamics of concomitant hydrolytic degradation and esterification of these materials were studied. 相似文献
14.
Kostko O Wrigge G Cheshnovsky O von Issendorff B 《The Journal of chemical physics》2005,123(22):221102
We present photoelectron spectroscopy studies on Zn(n) (-) in the size range of n=3-117. We show that zinc clusters exhibit a distinct transition in their electronic structure as a function of size. At small sizes (up to n=18) the clusters follow the Bloch-Wilson picture of the development of a metal from closed-shell atoms, exhibiting a gradual decrease of the gap between the fully occupied s band and the empty p band. For large sizes (n approximately or > 32) the band overlap allows the valence electrons to fully delocalize. This leads to an almost perfect free-electron density of states, as is demonstrated by discussing the spectra in the light of standard free-electron models and by comparison to the results obtained on sodium clusters. 相似文献
15.
Chen Wang Amit Fischer Avner Ehrlich Yaakov Nahmias Itamar Willner 《Chemical science》2020,11(17):4516
The enzymes glucose oxidase (GOx), acetylcholine esterase (AchE) and urease that drive biocatalytic transformations to alter pH, are integrated into pH-responsive DNA-based hydrogels. A two-enzyme-loaded hydrogel composed of GOx/urease or AchE/urease and a three-enzyme-loaded hydrogel composed of GOx/AchE/urease are presented. The biocatalytic transformations within the hydrogels lead to the dictated reconfiguration of nucleic acid bridges and the switchable control over the stiffness of the respective hydrogels. The switchable stiffness features are used to develop biocatalytically guided shape-memory and self-healing matrices. In addition, loading of GOx/insulin in a pH-responsive DNA-based hydrogel yields a glucose-triggered matrix for the controlled release of insulin, acting as an artificial pancreas. The release of insulin is controlled by the concentrations of glucose, hence, the biocatalytic insulin-loaded hydrogel provides an interesting sense-and-treat carrier for controlling diabetes.Biocatalytic control over the stiffness of pH-responsive hydrogels is applied to develop shape-memory, self-healing and controlled release matrices. 相似文献
16.
Gert Brandl Fritz Kastner Rainer Fritsch Herbert Zinner Albrecht Mannschreck 《Monatshefte für Chemie / Chemical Monthly》1992,123(11):1059-1069
Summary A procedure is described which serves to measure circular dichrograms () on line during stops of flow in liquid chromatography. Since the concentration of substrate in the spectrometer cell during the stop is not known, the differential absorption coefficients are calculated from the experimental differential absorbances A by means of UV absorption (i. e. photomultiplier voltage) data. Verifications of the procedure are obtained by its application to three substrates (Table 1), the () spectra of which were known. The present on-line technique is compared with a corresponding off-line method.The N,N-dimethylthiobenzamides1 and2 as well as the 9,10-phenanthrenequinone7 consist of interconvertible enantiomers because their planar states are destabilized by steric overcrowding of groups. The unknown dichrograms () of1, 2 and7 are obtained (Figs. 2 and 4) and discussed with reference to the helicities of these molecules.In memory of the late Professor Dr. Dr. h. c. Günther Snatzke. 相似文献
17.
In the present study, we demonstrate the benefits of a shear-driven rotating microchamber system for the enhancement of microarray hybridizations, by comparing the system with two commonly used hybridization techniques: purely diffusion-driven hybridization under coverslip and hybridization using a fully automated hybridization station, in which the sample is pumped in an oscillating manner. Starting from the same amount of DNA for the three different methods, a series of hybridization experiments using mouse lung and testis DNA is presented to demonstrate these benefits. The gain observed using the rotating microchamber is large: both in terms of analysis speed (up to tenfold increase) and in final spot intensity (up to sixfold increase). The gain is due to the combined effect of the hybridization chamber miniaturization (leading to a sample concentration increase if comparing iso-mass conditions) and the transport enhancement originating from the rotational shear-driven flow induced by the rotation of the chamber bottom wall. 相似文献
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Balest R Cho K Ford WT Lohner M Park H Rankin P Smith JG Alexander JP Bebek C Berger BE Berkelman K Bloom K Browder TE Cassel DG Cho HA Coffman DM Crowcroft DS Dickson M Drell PS Dumas DJ Ehrlich R Elia R Gaidarev P Garcia-Sciveres M Gittelman B Gray SW Hartill DL Heltsley BK Henderson S Jones CD Jones SL Kandaswamy J Katayama N Kim PC Kreinick DL Lee T Liu Y Ludwig GS Masui J Mevissen J Mistry NB Ng CR Nordberg E Patterson JR Peterson D Riley D Soffer A Avery P Freyberger A Lingel K Prescott C 《Physical review letters》1995,75(21):3809-3813
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Barish B Chadha M Chan S Cowen DF Eigen G Miller JS O'Grady C Urheim J Weinstein AJ Acosta D Athanas M Masek G Paar HP Gronberg J Kutschke R Menary S Morrison RJ Nakanishi S Nelson HN Nelson TK Qiao C Richman JD Ryd A Tajima H Sperka D Witherell MS Procario M Balest R Cho K Daoudi M Ford WT Johnson DR Lingel K Lohner M Rankin P Smith JG Alexander JP Bebek C Berkelman K Bloom K Browder TE Cassel DG Cho HA Coffman DM Crowcroft DS Drell PS Ehrlich R Gaidarev P Galik RS Garcia-Sciveres M Geiser B 《Physical review D: Particles and fields》1995,51(3):1014-1033