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91.
Ali A. Asgari Amir H. Abbassi Jafar Khodagholizadeh 《The European Physical Journal C - Particles and Fields》2014,74(6):1-11
Recent studies have shown that searches in the mono-photon and missing energy final state can be used to discover dark matter candidates at the ILC. While an excess in this final state over the Standard Model background would indicate the existence of a dark sector, no detailed information about the internal structure of this sector can be inferred. Here, we demonstrate how just a few observables can discriminate between various realisations of dark sectors, including e.g. the spin of mediators. 相似文献
92.
Rarefied gas flow in a parallel-plate micro-channel is considered, where a streamwise constant temperature gradient is applied in the channel walls. An analytical approach to the problem is conducted based on linearized and semi-linearized forms of the regularized 13-moment equations (R13 equations), which are a set of macroscopic transport equations for rarefied gases at the super-Burnett order. Typical nonequilibrium effects at the boundary, i.e., velocity slip, temperature jump, and formation of Knudsen boundary layers are investigated. Nonlinear contributions lead to temperature, density, and normal stress profiles across the channel which are not reported elsewhere in literature. 相似文献
93.
Peyman Niroomand 《Archiv der Mathematik》2010,94(5):401-403
Schur’s theorem states that for a group G finiteness of G/Z(G) implies the finiteness of G′. In this paper, we show the converse is true provided that G/Z(G) is finitely generated and in such case, we have |G/Z(G)| ≤ |G′|
d(G/Z(G)). In the special case of G being nilpotent, we prove |G/Z(G)| divides |G′|
d(G/Z(G)). 相似文献
94.
95.
Mehdi Ghandi Parham Asgari Abuzar Taheri Alireza Abbasi 《Central European Journal of Chemistry》2010,8(4):899-905
One-pot, three-component condensation of 2-hydroxybenzaldehyde derivatives, primary amines with alkyl isocyanides is reported.
N-alkyl-2-(2-hydroxyphenyl)-2-iminoacetamide derivatives are generated presumably via the preliminary formation of N, N′-disubstituted benzo[b]furan-2,3-diamines and subsequent oxidation with molecular oxygen.
相似文献
96.
Minoo Dabiri Peyman Salehi Mahboobeh Bahramnejad Mohsen Alizadeh 《Monatshefte für Chemie / Chemical Monthly》2010,46(6):877-881
Abstract
An effective one-pot three-component route to 4(3H)-quinazolinones from commercially available starting materials is reported. Thus, isatoic anhydride reacted with ammonium acetate or primary amines and aldehydes in the presence of iodine to produce the corresponding quinazolinone derivatives in moderate to good yields. 相似文献97.
Multiple criteria facility location problems: A survey 总被引:1,自引:0,他引:1
This paper provides a review on recent efforts and development in multi-criteria location problems in three categories including bi-objective, multi-objective and multi-attribute problems and their solution methods. Also, it provides an overview on various criteria used. While there are a few chapters or sections in different location books related to this topic, we have not seen any comprehensive review papers or book chapter that can cover it. We believe this paper can be used as a complementary and updated version. 相似文献
98.
Kh. Jahanbani R. Asgari 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,73(2):247-252
We study the optical conductivity of a doped graphene
when a sublattice symmetry breaking is occurred in the presence of
the electron-phonon interaction. Our study is based on the Kubo
formula that is established upon the retarded self-energy. We
report new features of both the real and imaginary parts of the
quasiparticle self-energy in the presence of a gap opening. We
find an analytical expression for the renormalized Fermi velocity
of massive Dirac Fermions over broad ranges of electron densities,
gap values and the electron-phonon coupling constants. Finally we
conclude that the inclusion of the renormalized Fermi energy and
the band gap effects are indeed crucial to get reasonable feature
for the optical conductivity. 相似文献
99.
Mohammad Hossein Mirjalili Peyman Salehi Ali Sonboli Masood Mohammadi Vala 《Chemistry of Natural Compounds》2006,42(1):19-23
In this paper the variation in the quantity and quality of the essential oil of Salvia officinalis during its life cycle stages is reported. The oils were obtained by hydrodistillation of air-dried samples. The yield of
essential oil (w/w %) in different stages was in the order: floral budding (0.9%) > vegetative (0.7%) > flowering (0.5%) >
immature fruit (0.4%) > ripen fruit (0.2%). The essential oils were analyzed by GC and GC-MS. In total, 36, 41, 40, 38, and
41 constituents were identified and quantified in the subsequent stages, respectively. Oxygenated monoterpenes were the main
group of compounds in the fruiting set (56.9%), vegetative (48.5%), flowering (47.7%), and floral budding (45.3%) stage. 1,8-cineole
as one of the major constituents of all samples was lower in the vegetative stage and gradually increased in subsequent harvesting
times to reach a maximum in flowering and then decreased in the fruiting set. In contrast, the globulol content was higher
in the first stage and decreased drastically during fruit maturation.
Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 16–19, January–February, 2006. 相似文献
100.
Minoo Dabiri Peyman Salehi Mostafa Baghbanzadeh Ali A. Mohammadi 《Tetrahedron letters》2005,46(36):6123-6126
KAl(SO4)2·12H2O was found to catalyze efficiently a one-pot three-component cyclocondensation of isatoic anhydride and primary amines or ammonia sources such as (NH4)2CO3, NH4OAc and NH4Cl with aromatic aldehydes under mild conditions to afford the corresponding mono- and disubstituted 2,3-dihydroquinazolin-4(1H)-ones in good yields. 相似文献