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51.
The chemical composition of the essential oils of the flowers and leaves of Anthemis hyalina were analyzed by GC and GC-MS for the first time. The oils were found to contain seventy-two components. cis-Chrysanthenyl acetate (14.9% and 17.8%), camphor (11.6% and 1.7%), terpinen-4-ol (8.3% and 1.2%), germacrene-D (5.1% and
2.1%), β-caryophyllene (4.1% and 5.4%), myrcene (3.6% and 16.9%), bicyclogermacrene (3.5% and 0.9%), α-pinene (2.3% and 4.1%), cis-β-ocimene (2.1% and 4.3%) and isospathulenol (0.4% and 4.3%) were found to be the major constituents of the oils of flowers
and leaves respectively.
Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 428–429, September–October, 2006. 相似文献
52.
Matrix Heterogeneity Effects on Gas Transport and Adsorption in Coalbed and Shale Gas Reservoirs 总被引:2,自引:0,他引:2
In coalbeds and shales, gas transport and storage are important for accurate prediction of production rates and for the consideration
of subsurface greenhouse gas sequestration. They involve coupled fluid phenomena in porous medium including viscous flow,
diffusive transport, and adsorption. Standard approach to describe gas–matrix interactions is deterministic and neglects the
effects of local spatial heterogeneities in porosity and material content of the matrix. In this study, adopting weak-noise
and mean-field approximations and using a statistical approach in spectral domain, matrix heterogeneity effects are investigated
in the presence of non-equilibrium adsorption with random partition coefficient. It is found that the local heterogeneities
can generate non-trivial transport and kinetic effects which retard gas release from the matrix and influence the ultimate
gas recovery adversely. Macro-transport shows 1/[1 + N
Pe
/(1 + N
Pe
)] dependence on the Péclet number, and persists at the diffusive ultra-low permeability limit. Macro-kinetics is directly
related to Thiele modulus by the following expression: N
Th
/(1 + 2N
Pe
). It leads to trapping of gas in the adsorbed phase during its release from the matrix, and to an adsorption threshold during
the gas uptake by the matrix. Both effects are proportional to the initially available adsorbed gas amount and becomes more
pronounced with the increasing variance of the porosity field. Consequently, a new upscaled deterministic gas mass balance
is proposed for practical purposes. Numerical results are presented showing free and adsorbed gas distributions and fractional
gas sorption curves for unipore coal matrix exhibiting Gaussian porosity distribution. This study is a unique approach for
our further understanding of the coalbeds and gas shales, and it is important for the development of sound numerical gas production
and sequestration models. 相似文献
53.
Dadkhah Davood Zomorodi Mariam Hosseini Seyed Ebrahim 《International Journal of Theoretical Physics》2021,60(9):3271-3285
International Journal of Theoretical Physics - In the present work, a novel approach was proposed to optimize the teleportation cost in Distributed Quantum Circuits (DQCs) by applying a new... 相似文献
54.
55.
Ebrahim Hashemi 《Mediterranean Journal of Mathematics》2011,8(2):207-214
Let R be a ring with unity and M be a right R-module. The system M[x] forms a left near R[x]-module under addition and substitution operations. In this paper we extend the study of annihilator conditions on nearring
of polynomials to left near R[x]-module M[x], when M is a reduced Baer module. Also, we give a characterization of reduced modules. As a corollary we obtain some results of Birkenmeier
and Huang [3]. 相似文献
56.
Ahmed A. Ebrahim 《Brazilian Journal of Physics》2011,41(2-3):146-153
Angular distributions of differential cross sections for the 12C(π ±, π ±)12C and 12C(π ±, π ±)12C* reactions at pion kinetic energy ranging from 50 to 260 MeV have been analyzed with the 3α-particle model of 12C. The model provides good fits to a wide range of data. Differential cross sections for inelastic transitions to the (2?+?; 4.44 MeV) and (3???; 9.64 MeV) states in 12C are computed and the deformation lengths δ 2 and δ 3 are extracted. It is found that the extracted deformation lengths are sensitive to the nuclear model used and similar to the corresponding values found with other probes and nuclear models. 相似文献
57.
Mahmood Alaghmandan Yemon Choi Ebrahim Samei 《Journal of Mathematical Analysis and Applications》2014
Let G be a restricted direct product of finite groups {Gi}i∈I, and let Z?1(G) denote the centre of its group algebra. We show that Z?1(G) is amenable if and only if Gi is abelian for all but finitely many i , and characterize the maximal ideals of Z?1(G) which have bounded approximate identities. We also study when an algebra character of Z?1(G) belongs to c0 or ?p and provide a variety of examples. 相似文献
58.
Ebrahim Ghorbani 《Graphs and Combinatorics》2013,29(5):1377-1389
We determine all graphs whose matching polynomials have at most five distinct zeros. As a consequence, we find new families of graphs which are determined by their matching polynomials. 相似文献
59.
60.
Asadollah Zarif Farhad Amarloo Faeze Pourazimi Najmeh Kaftani Zahra Rostamabadi Ebrahim 《Journal of fluorescence》2022,32(5):1639-1650
Journal of Fluorescence - Malachite green (MG) is a dye that has been presented to use as photosensitizers for photodynamic therapy (PDT). Nonlinear absorption coefficient (β) and nonlinear... 相似文献