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81.
82.
Q-switching of a diode-pumped Nd:YVO4 laser using a quadrupole electro-optic deflector 总被引:3,自引:0,他引:3
G.J. Friel R.S. Conroy A.J. Kemp B.D. Sinclair J.M. Ley 《Applied physics. B, Lasers and optics》1998,67(2):267-270
4 laser and this produced 1.5-ns pulses of 7 kW peak power at a repetition rate of 20 kHz.
Received: 11 May 1998 相似文献
83.
Reaction of arylidene imines of methyl phenylglycinate with 2 moles of dimethyl acetylenedicarboxylate (ADE) leads, via an intermediate Δ3-pyrroline, to loss of the original methyl phenylglycinate moiety and formation of 2-aryl-3,4,5-tricarbo methoxypyrroles. 相似文献
84.
85.
Ashleigh N. Bristol Brooke P. Carpenter Ashley N. Davis Lisa K. Kemp Vijayaraghavan Rangachari Shahid Karim Sarah E. Morgan 《Macromolecular bioscience》2020,20(8)
Gliadin, a component of gluten and a known epitope, is implicated in celiac disease (CeD) and results in an inflammatory response in CeD patients when consumed. Acrylamide‐based polyelectrolytes are employed as models to determine the effect of molecular weight and pendent group on non‐covalent interaction modes with gliadin in vitro. Poly(sodium 2‐acrylamido‐2‐methylpropane sulfonate) and poly(sodium 3‐methylpropyl‐3‐butanoate) are synthesized via aqueous reversible addition fragmentation chain transfer (aRAFT) polymerization and characterized by gel permeation chromatography‐multiangle laser light scattering. The polymer/gliadin blends are examined via circular dichroism, zeta potential measurements, 8‐anilinonaphthalene‐1‐sulfonic acid fluorescence spectroscopy, and dynamic light scattering. Acrylamide polymers containing strong anionic pendent groups have a profound effect on gliadin secondary structure and solution behavior below the isoelectric point, while polymers containing hydrophobic character only have a minor impact. The polymers have little effect on gliadin secondary structure and solution behavior at the isoelectric point. 相似文献
86.
Microchip laser-pumped continuous-wave doubly resonant optical parametric oscillator 总被引:1,自引:0,他引:1
We report what we believe to be the first use of a multilongitudinal-mode frequency-doubled microchip laser to pump a doubly resonant optical parametric oscillator (OPO). This compact OPO is based on potassium titanyl phosphate (KTP) and operates with a low pump power threshold of 35 mW. The OPO output consists of a single pair of signal and idler modes even though it is pumped with a multilongitudinal-mode pump laser. We achieved smooth tuning (1.7 GHz) of the output frequencies by temperature tuning of the pump laser. 相似文献
87.
E. Butler G. B. Andresen M. D. Ashkezari M. Baquero-Ruiz W. Bertsche P. D. Bowe C. L. Cesar S. Chapman M. Charlton A. Deller S. Eriksson J. Fajans T. Friesen M. C. Fujiwara D. R. Gill A. Gutierrez J. S. Hangst W. N. Hardy M. E. Hayden A. J. Humphries R. Hydomako M. J. Jenkins S. Jonsell L. V. J?rgensen S. L. Kemp L. Kurchaninov N. Madsen S. Menary P. Nolan K. Olchanski A. Olin A. Povilus P. Pusa C. ?. Rasmussen F. Robicheaux E. Sarid S. Seif el Nasr D. M. Silveira C. So J. W. Storey R. I. Thompson D. P. van der Werf J. S. Wurtele Y. Yamazaki 《Hyperfine Interactions》2012,212(1-3):15-29
88.
89.
Kemp JP Chen ZY 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,60(3):2994-2998
We present a semianalytical approach to the determination of the dynamic properties of randomly branched polymers under the Rouse approximation. The principal procedure is based on examining an eigenvalue spectrum which represents the average dynamic behavior of various structures. The calculated spectra show that the eigenvalue distribution is random even within a single structure, which in turn produces a continuous spectrum of values for the entire class. The autocorrelation function for the square of the radius of gyration was calculated based on these spectra, which confirms that the dynamics are nonexponential as earlier reported. A universal stretched exponent is also found in this study. 相似文献
90.
DanielS. Kemp 《Helvetica chimica acta》2002,85(12):4392-4423
New forms of Lifson? Roig algorithms are introduced for modeling stabilities of helices formed by polypeptides derived from α‐amino acids. The principles of constructing and generalizing these algorithms are developed, and their application to modeling of circular dichroism ellipticities and protection factors derived from H/D exchange of α‐peptide backbone amide residues are critically reviewed. With the aim of comparing the properties of structured conformations formed by α‐ and β‐peptides, the intrinsic limitations of Lifson? Roig algorithms and their underlying assumptions are analyzed. Lifson? Roig state sums that provide easy structural analysis are generated by new algorithms based on products of 8×8 and 16×16 matrices, and a simple protocol is introduced for generating new state sums that are tailored for specific purposes. The N‐ and C‐capping of highly helical α‐peptides by means of tailored helix‐stabilizing templates is shown to result in helical conformational manifolds that approach those of helical β‐peptides in conformational homogeneity. 相似文献