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排序方式: 共有956条查询结果,搜索用时 31 毫秒
61.
Kosyakov Dmitry S. Anikeenko Elena A. Ul’yanovskii Nikolay V. Khoroshev Oleg Yu Shavrina Irina S. Gorbova Natalya S. 《Analytical and bioanalytical chemistry》2018,410(28):7429-7439
Analytical and Bioanalytical Chemistry - The use of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry for the study of lignin is still extremely limited due to its low... 相似文献
62.
Chris Capaccio Nikolay S. Stoykov Raji Sundararajan David A. Dean 《Journal of Electrostatics》2009,67(4):652-662
The application of appropriate electric fields to cells and tissues, termed electroporation, can result in efficient and safe gene transfer. We have shown previously that this approach results in high level gene transfer to and expression in the vasculature of living animals. This paper presents the results of an electric field distribution study of a rat mesenteric vasculature model using the Finite-Element Time-Domain (FETD) technique. A novelty of this work is the use of Debye dispersive dielectric parameters, as the electrical response of biological tissues is inherently frequency-dependent. The results compare fairly well with experimental findings. 相似文献
63.
Magda D Gerasimchuk N Lecane P Miller RA Biaglow JE Sessler JL 《Chemical communications (Cambridge, England)》2002,(22):2730-2731
Motexafin gadolinium (MGd) oxidizes ascorbate, in neutral buffer and in cell culture, forming reactive oxygen species and a coordination polymer with oxalate. 相似文献
64.
Yurij?Stoyan Guntram?ScheithauerEmail author Nikolay?Gil Tatiana?Romanova 《4OR: A Quarterly Journal of Operations Research》2004,2(1):69-84
Within two-dimensional cutting and packing problems with irregular shaped objects, the concept of
-functions has been proven to be very helpful for several solution approaches. In order to construct such
-functions a previous work, in which so-called primary objects are considered, is continued. Now
-functions are constructed for pairs of objects which can be represented as a finite combination (union, intersection, complement) of primary objects which allows the handling of arbitrary shaped objects by appropriate approximations of sufficient accuracy.Received: October 2002, Revised: October 2003, AMS classification:
65K05, 90C26, 90B06All correspondence to: Guntram Scheithauer 相似文献
65.
Depending on the Hamiltonian parameters, two-component bosons in an optical lattice can form at least three different superfluid phases in which both components participate in the superflow: a (strongly interacting) mixture of two miscible superfluids (2SF), a paired superfluid (PSF) vacuum, and (at a commensurate total filling factor) the super-counter-fluid (SCF) state. We study the universal properties of the 2SF-PSF and 2SF-SCF quantum phase transitions and show that (i) they can be mapped onto each other and (ii) their universality class is identical to the (d+1)-dimensional normal-superfluid transition in a single-component liquid. The finite-temperature 2SF-PSF(SCF) transitions and the topological properties of 2SF-PSF(SCF) interfaces are also discussed. 相似文献
66.
Polarization control of optical transmission of a periodic array of elliptical nanoholes in a metal film 总被引:1,自引:0,他引:1
The spectral dependences of polarized optical transmission of a metal film with a periodic array of elliptical nanoholes have been studied. Such nanostructured metal films exhibit enhanced broadband optical transmission that one can control by selecting the polarization of incident and (or) transmitted light. 相似文献
67.
Different scavenging techniques using polymer-supported sequestration agents are described for the purification steps in the synthesis of N3-acylated dihydropyrimidines. For scavenging both excess anhydride and unwanted byproducts, polystyrene and silica supported diamines, aminomethyl-functionalized SynPhase Lanterns and diethylenetriamine StratoSpheres Plugs are used. In both synthesis and purification microwave flash heating was utilized, reducing reaction times from hours to minutes. These two steps coupled with an efficient solid-phase extraction (SPE) workup allowed the generation of a 28-member library of N3-acylated dihydropyrimidines using anhydrides. Using related protocols a 15-member library of N3-functionalized dihydropyrimidines utilizing acid chlorides as acylating reagents was also obtained. 相似文献
68.
Nikolay V. Shabanov D. Huang R.E. Dickinson 《Journal of Quantitative Spectroscopy & Radiative Transfer》2007,107(2):236-262
Modeling of the radiation regime of a mixture of vegetation species is a fundamental problem of the Earth's land remote sensing and climate applications. The major existing approaches, including the linear mixture model and the turbid medium (TM) mixture radiative transfer model, provide only an approximate solution to this problem. In this study, we developed the stochastic mixture radiative transfer (SMRT) model, a mathematically exact tool to evaluate radiation regime in a natural canopy with spatially varying optical properties, that is, canopy, which exhibits a structured mixture of vegetation species and gaps. The model solves for the radiation quantities, direct input to the remote sensing/climate applications: mean radiation fluxes over whole mixture and over individual species. The canopy structure is parameterized in the SMRT model in terms of two stochastic moments: the probability of finding species and the conditional pair-correlation of species. The second moment is responsible for the 3D radiation effects, namely, radiation streaming through gaps without interaction with vegetation and variation of the radiation fluxes between different species. We performed analytical and numerical analysis of the radiation effects, simulated with the SMRT model for the three cases of canopy structure: (a) non-ordered mixture of species and gaps (TM); (b) ordered mixture of species without gaps; and (c) ordered mixture of species with gaps. The analysis indicates that the variation of radiation fluxes between different species is proportional to the variation of species optical properties (leaf albedo, density of foliage, etc.) Gaps introduce significant disturbance to the radiation regime in the canopy as their optical properties constitute major contrast to those of any vegetation species. The SMRT model resolves deficiencies of the major existing mixture models: ignorance of species radiation coupling via multiple scattering of photons (the linear mixture model) or overestimation of this coupling due to neglecting spatial clumping of species (the TM approach). Thus, based on the former experience with mixture modeling, this study establishes an advanced theoretical basis for future mixture applications. 相似文献
69.
70.
Egor V. Verbitskiy Svetlana A. Baskakova Natal’ya A. Gerasimova Natal’ya P. Evstigneeva Natal’ya V. Zil’berberg Nikolay V. Kungurov Marionella A. Kravchenko Gennady L. Rusinov Oleg N. Chupakhina Valery N. Charushin 《Mendeleev Communications》2018,28(4):393-395
A facile synthetic approach to 5-arylamino-4-(5-nitrofuran- 2-yl)pyrimidines by the Buchwald–Hartwig cross-coupling with various anilines has been developed. All synthesized compounds demonstrated a significant level of in vitro antibacterial activity against Neisseria gonorrhoeae, Streptococcus pyogene and Staphylococcus aureus, including their drug-resistant strains, which is much higher than that of the commercial drug Spectinomycin. 相似文献