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91.
Series of new mixed aza-oxo-thia macrocyclic ligands {2,6,12,16-tetraaza-1,7,11,17-tetraoxo-9,19-dithia-[(4′-methyl-5′,4,3′)(14′-methyl-15′,14,13′)]ditriazine}cyclocosane (L 1 ); {2,6,13,17-teraaza-1,7,12,18-tetraoxo-9,10,20,21-tetrathia-[(4′-methyl-5′,4,3′)(15′-methyl-14′,16′,15)]di-triazine}cyclodocosane (L 2 ); {2,6,14,18-tetraaza-1,7,13,19-tetraoxo-10,22-dithia-[(4′-methyl-5′,3′,4)(16′-methyl-15′,17′,16)]ditriazine}cyclotetracosane (L 3 ) and {2,6,15,19-tetraaza-1,7,14,12-tetraoxo-10,11,23,24-tetrathia-[(4′-methyl-5′,4,3′)(17′-methyl-8′,17,16′)]ditriazine}cyclohexa-cosane (L 4 ) were synthesized. The structural features of the compounds have been studied by elemental analyses, Mass, FT-Raman, FT-IR, 1H and 13C NMR spectroscopy. The antimicrobial activities of the ligands were evaluated using disk diffusion method in dimethyl sulfoxide as well as the minimal inhibitory concentration (MIC) dilution method, against 9 bacteria. The obtained results from disk diffusion method were assessed in side-by-side comparison with those of Penicillin-g, Ampicillin, Cefotaxime, Vancomycin, Oflaxacin, and Tetracyclin, well-known antibacterial agents. The results from dilution procedure were compared with Gentamycin as antibacterial and Nystatin as antifungal. The antifungal activities are reported on five yeast cultures namely Candida albicans, Kluyveromyces fragilis, Rhodotorula rubra, Debaryomyces hansenii, and Hanseniaspora guilliermondii, and the results are referenced with Nystatin, Ketaconazole, and Clotrimazole, commercial antifungal agents. In most cases, the compounds show strong antifungal activity in the comparison tests.  相似文献   
92.
93.
Markov additive processes. I   总被引:1,自引:0,他引:1  
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94.
We investigate a procedure for obtaining the thermodynamical potential at finite temperature and density for a relativistic system of fermions in the presence of condensed bosons. After we have considered the formalism based on a relativistic form of the Landau theory of quantum liquids, we analyze a model with the Yukawa interaction between the spinor and the pseudoscalar fields. Finally we discuss our results in relationship to some known cases of condensation in high energy physics.  相似文献   
95.
Bromination of 3-bromo-6,7-benzobicyclo [3.2.1] octa-2,6-diene at ?50°C gave anti-tribromo adduct (5) in essentially quantitative yield. The double dehydrobromination of (5) was achieved using potassium tert.- butoxide to give 2-bromo-benzobarrelene (7). Reaction of (7) with n-BuLi and subsequent quenching with CH3I, CO2, and dimethylformamide afforded the corresponding substituted benzobarrelenes in high yield.  相似文献   
96.
We prove almost-sure exponential localization of all the eigenfunctions and nondegeneracy of the spectrum for random discrete Schrödinger operators on one- and quasi-one-dimensional lattices. This paper provides a much simpler proof of these results than previous approaches and extends to a much wider class of systems; we remark in particular that the singular continuous spectrum observed in some quasiperiodic systems disappears under arbitrarily small local perturbations of the potential. Our results allow us to prove that, e.g., for strong disorder, the smallest positive Lyapunov exponent of some products of random matrices does not vanish as the size of the matrices increases to infinity.  相似文献   
97.
98.
We prove identities between integrated Ursell functions and derivatives of the pressure in the thermodynamic limit, for multicomponent classical spin systems which obey the Lee-Yang theorem and some form of Gaussian domination, when the susceptibility is finite (T>T c). Following Refs. 3 and 4, we view the moment generating function of the magnetization as the inverse of an infinitely divisible characteristic function. Fluctuation susceptibility relations of all orders then follow by bounding the corresponding cumulants, taken in zero external field. High-order cumulants are bounded in terms of the susceptibility using Gaussian and Simon's inequalities for short-range interactions.  相似文献   
99.
This study proposes and construct a primitive quantum arithmetic logic unit (qALU) based on the quantum Fourier transform (QFT). The qALU is capable of performing arithmetic ADD (addition) and logic NAND gate operations. It designs a scalable quantum circuit and presents the circuits for driving ADD and NAND operations on two-input and four-input quantum channels, respectively. By comparing the required number of quantum gates for serial and parallel architectures in executing arithmetic addition, it evaluates the performance. It also execute the proposed quantum Fourier transform-based qALU design on real quantum processor hardware provided by IBM. The results demonstrate that the proposed circuit can perform arithmetic and logic operations with a high success rate. Furthermore, it discusses in detail the potential implementations of the qALU circuit in the field of computer science, highlighting the possibility of constructing a soft-core processor on a quantum processing unit.  相似文献   
100.
Let R be a ring with identity. A module \(M_R\) is called an r-semisimple module if for any right ideal I of R, MI is a direct summand of \(M_R\) which is a generalization of semisimple and second modules. We investigate when an r-semisimple ring is semisimple and prove that a ring R with the number of nonzero proper ideals \(\le \)4 and \(J(R)=0\) is r-semisimple. Moreover, we prove that R is an r-semisimple ring if and only if it is a direct sum of simple rings and we investigate the structure of module whenever R is an r-semisimple ring.  相似文献   
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