排序方式: 共有40条查询结果,搜索用时 31 毫秒
1.
O. O. Brovko D. Valenti S. I. Lebedenko B. Spagnolo A. Yu. Chikishev 《Moscow University Physics Bulletin》2010,65(3):180-183
The role of harmonic and random external forces in a phenomenological nonlinear model of optical heartbeats is investigated.
External forces trigger damped oscillations at the natural frequency of the system and higher harmonics. The numerical results
are compared with experimental ones. 相似文献
2.
O. Brovko A. Grebentsov N. Morozov E. Syresin M. Yurkov 《Physics of Particles and Nuclei Letters》2016,13(3):384-389
Diagnostic technique applied for FEL ultrashort electron bunches is developed at JINR-DESY collaboration within the framework of the FLASH and XFEL projects. Photon diagnostics are based on calorimetric measurements and detection of undulator radiation. The infrared undulator constructed at JINR and installed at FLASH is used for longitudinal bunch shape measurements and for two-color lasing provided by the FIR and VUV undulators. The pump probe experiments with VUV and FIR undulators provide the bunch profile measurements with resolution of several femtosecond. The new three microchannel plates (MCP) detectors operated in X-ray range are under development now in JINR for SASE1-SASE 3 European XFEL. 相似文献
3.
N. N. Agapov A. V. Alfeev V. A. Andreev V. I. Batin O. I. Brovko A. V. Butenko B. -R. V. Vasilishin V. I. Volkov A. I. Govorov E. D. Donets E. E. Donets D. E. Donets A. V. Eliseev I. B. Issinskii V. N. Karpinskii V. D. Kekelidze A. D. Kovalenko O. S. Kozlov I. N. Meshkov V. A. Mikhailov V. A. Monchinskii P. A. Rukoyatkin N. V. Semin A. O. Sidorin A. N. Sissakian V. M. Slepnev A. S. Sorin G. V. Trubnikov G. G. Khodzhibagiyan 《Physics of Particles and Nuclei Letters》2010,7(7):442-445
The Nuclotron superconducting synchrotron was constructed in 1987–1992 [1]; it is the world’s first synchrotron based on fast cycling “window frame” electromagnets with a superconducting coil. For a design field of dipole magnets of 2 T, the magnetic rigidity is 45 T m, which corresponds to the energy of heavy nuclei (for example, gold) of 4.5 GeV/nucleon. The Nuclotron accelerator complex is currently being upgraded (the Nuclotron-M project); this upgrade is considered a key part of the first stage of fulfilling the new Joint Institute for Nuclear Research (JINR) project: the Nuclotron-based Ion Collider fAcility and Multi-Purpose Detector (NICA/MPD). The most important task of this new project is the preparation of basic Nuclotron systems for its reliable operation as part of the NICA accelerator complex. Basic results of activity on the project, which started in 2007, are presented and the results of the last Nuclotron runs are analyzed. 相似文献
4.
Alexander Fainleib Elena Slinchenko Olexander Brovko Ludmila Sergeeva Valentina Dubkova Harry Frisch 《Macromolecular Symposia》2001,169(1):179-184
The influence of carbon fibre on the curing kinetics of the prepolymer based on bisphenol A cyanurate and epoxy resin has been studied using infra‐red spectroscopy. It was found that curing process of prepolymer is very complicated. It is shown that in curing the prepolymer a number of the sequential transformations of ones cycle structure into others occurs. An introduction of the carbon fiber (CF) of two types, original CF and modified CF (MCF) containing phosphate groups, affect strongly the prepolymer curing. Both CF and MCF accelerate the conversion rate of epoxy groups. In the case of cyanate groups, the former does not practically affect their conversion whereas the latter decelerates strongly this process. In the paper the influence mechanism of CF is considered. 相似文献
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6.
V. N. Marshalkin D. A. Brovko A. V. Samet V. V. Semenov 《Russian Journal of Organic Chemistry》2001,37(9):1244-1248
2,4-Dinitro- and 2,4,6-trinitrotoluenes react with phthalic anhydride in boiling N,N-dimethylaniline to give nitro group reduction products. 相似文献
7.
Reaction mechanisms for the formation of the keto-form of oxyluciferin (OxyLH(2)) from the luciferin of fireflies via a dioxetanone intermediate are predicted using the B3LYP/6-31G theoretical method. The ring opening of a model dioxetanone and the decarboxylation proceed in one step via a singlet diradical transition structure with an activation barrier of 18.1 and an exothermicity of 90.8 kcal/mol. The S(0) --> S(1) vertical excitation energies predicted with time dependent density functional theory, TDDFT B3LYP/6-31+G, for the anionic and neutral forms of OxyLH(2) are in the range of 60 to 80 kcal/mol. These energetic results support the generally accepted theory of chemically initiated electron exchange luminescence (CIEEL). The chemical origin of the multicolor bioluminescence from OxyLH(2) is examined theoretically using the TDDFT B3LYP/6-31+G, ZINDO//B3LYP/6-31+G, and CIS/6-31G methods. A change in color of the light emission upon rotation of the two rings in the S(1) excited state of OxyLH(2) is unlikely because both possible emitters, the planar keto- and enol-forms, are minima on the S(1) potential energy surface. The participation of the enol-forms of OxyLH(2) in bioluminescence is plausible but not required to explain the multicolor emission. According to predictions at the TDDFT B3LYP level, the color of the bioluminescence depends on the polarization of the OxyLH(2) in the microenvironment of the enzyme-OxyLH(2) complex. 相似文献
8.
Bioluminescence spectra for various native and mutant luciferases from fireflies and beetles were analyzed in the light of the known theoretical concepts on the influence of the microenvironment of the emitter on its emission spectra. The mechanism for the explanation of the nature of changing bioluminescence spectra for natural and artificial mutations of the amino acid residues in the protein globule of luciferases was proposed. 相似文献
9.
Aggarwal MM Ahammed Z Alakhverdyants AV Alekseev I Alford J Anderson BD Anson CD Arkhipkin D Averichev GS Balewski J Beavis DR Bellwied R Betancourt MJ Betts RR Bhasin A Bhati AK Bichsel H Bielcik J Bielcikova J Biritz B Bland LC Borowski W Bouchet J Braidot E Brandin AV Bridgeman A Brovko SG Bruna E Bueltmann S Bunzarov I Burton TP Cai XZ Caines H Calderón de la Barca Sánchez M Cebra D Cendejas R Cervantes MC Chajecki Z Chaloupka P Chattopadhyay S Chen HF Chen JH Chen JY Cheng J Cherney M 《Physical review letters》2011,106(6):062002
We report the first measurement of the parity-violating single-spin asymmetries for midrapidity decay positrons and electrons from W+ and W- boson production in longitudinally polarized proton-proton collisions at sqrt[s] = 500 GeV by the STAR experiment at RHIC. The measured asymmetries, A(L)(W+) = -0.27 ± 0.10(stat.) ± 0.02(syst.) ± 0.03(norm.) and A(L)(W-) = 0.14 ± 0.19(stat.) ± 0.02(syst.) ± 0.01(norm.), are consistent with theory predictions, which are large and of opposite sign. These predictions are based on polarized quark and antiquark distribution functions constrained by polarized deep-inelastic scattering measurements. 相似文献
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