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31.
32.
Huynh Phuong Truc Tran Trinh Pham Ngoc Dinh Binh Thanh Nguyen Linh Thi Truc Truong Loan Thi Hong Tran Anh Tuan Ho Dung Manh Van Nguyen Dong 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):663-671
Journal of Radioanalytical and Nuclear Chemistry - The aim of this study was to find trace elements that increase risk of breast cancer based on the deviation of the concentration of trace elements... 相似文献
33.
Duong Quoc Hoan Le Thi Hoa Trinh Thi Huan Nguyen Huu Dinh 《Journal of heterocyclic chemistry》2020,57(4):1720-1728
An efficient and simple method has been reported for the synthesis of 4-(1-Chloro-1-nitroethyl)-6,7-dimethoxy-2-methylquinazoline ( 2 ) as a key compound for further transformation to other novel 6,7-dimethoxy-2-methyl-4-substituted quinazolines. The structure of the synthesized compounds was characterized by spectroscopic methods. The pathway of some unprecedented reactions was proposed. (E)-1-(6,7-dimethoxy-2-methylquinazolin-4-yl)-3-(4-nitrophenyl)prop-2-en-1-one (11) exhibits high in vitro cytotoxicity on three cell lines, Hepatocellular carcinoma (Hep-G2), Human lung carcinoma (LU-1), and Human breast carcinoma (MCF-7) with IC50 of 2.1, 11.6 and 2.2 μM, respectively. 相似文献
34.
Cong Nguyen Dinh Duc Luu Hoang Hong Phan Thanh 《Journal of Dynamics and Differential Equations》2022,34(1):605-636
We study the asymptotic dynamics of stochastic Young differential delay equations under the regular assumptions on Lipschitz continuity of the coefficient functions. Our main results show that, if there is a linear part in the drift term which has no delay factor and has eigenvalues of negative real parts, then the generated random dynamical system possesses a random pullback attractor provided that the Lipschitz coefficients of the remaining parts are small.
相似文献35.
Trung T. Dinh 《代数通讯》2013,41(1):109-123
Recently, Brenner and Monsky found an example of an ideal in a hypersurface ring whose tight closure does not commute with localization, thus answered the localization problem in tight closure theory in the negative. In this article, we use Monsky's calculations to analyze the set of associated primes of the Frobenius powers of this ideal and show that this set is infinite. 相似文献
36.
37.
Nguyen Huy Dan Pham Thi ThanhNguyen Hai Yen Nguyen Thi Thanh Huyen Duong Dinh Thang Luu Tien Hung 《Journal of magnetism and magnetic materials》2012,324(7):1435-1439
We have observed magnetic anisotropy in bulk Nd55−xCoxFe30Al10B5 (x=10, 15 and 20) alloys prepared by copper mold suction casting method with a presence of external magnetic field (quenching field) μ0H=0.25 T. By changing direction of the measuring field from perpendicular to parallel one in comparison with that of the quenching field, coercive force of the alloys slightly decreases while remanent magnetization and squareness of hysteresis loop increase more clearly. It is also found that the higher Co-concentration in the alloys the larger magnetic anisotropy is induced. The structure analyses manifest nanocrystalline particles embedded in residual amorphous matrix of the alloys. The size of the particles is in range of 10-30 nm and their crystalline phases consist of Nd2(Fe,Co)14B, Nd3Co, Nd3Al, NdAl2 and Nd. 相似文献
38.
Globally solving a nonlinear UAV task assignment problem by stochastic and deterministic optimization approaches 总被引:1,自引:0,他引:1
In this paper, we consider a task allocation model that consists of assigning a set of m unmanned aerial vehicles (UAVs) to a set of n tasks in an optimal way. The optimality is quantified by target scores. The mission is to maximize the target score while
satisfying capacity constraints of both the UAVs and the tasks. This problem is known to be NP-hard. Existing algorithms are
not suitable for the large scale setting. Scalability and robustness are recognized as two main issues. We deal with these
issues by two optimization approaches. The first approach is the Cross-Entropy (CE) method, a generic and practical tool of
stochastic optimization for solving NP-hard problem. The second one is Branch and Bound algorithm, an efficient classical
tool of global deterministic optimization. The numerical results show the efficiency of our approaches, in particular the
CE method for very large scale setting. 相似文献
39.
S. M. Arakelian A. V. Osipov I. O. Skryabin Tran Dinh Phong Nguyen Tran Thuath 《Bulletin of the Russian Academy of Sciences: Physics》2017,81(12):1416-1419
The current-voltage relationships of deposited structures are measured for cluster structures consisting of nanoparticles of lead telluride. Variation in the value of the tunnel current is shown. Optimum conditions for the possible emergence of quantum-hopping conductivity due to carrier tunneling (the characteristic sizes of the nanoclusters and the distances between them) are determined. 相似文献
40.
Fundamental equations of the theory of spatially reinforced media with a matrix reinforced by spherical particles are proposed on the basis of a linearly reinforced layer and tl.e hypothesis of a longitudinal state. For an arbitrary orientation of the fibers, the generalized elasticity equation for composites was found to contain 21 elastic constants and approximate formulas were derived for their determination.Presented at the Ninth International Conference on the Mechanics of Composite Materials, Riga. Latvia (October, 1995).Communication 1. see preceding article.A. A. Blagonravov Institute of Mechanical Engineering. Russian Academy of Sciences, Moscow. Russian. Translated from Mekhanika Kompozitnykh Materialov, Vol. 32, No. 3, pp. 306–316, May–June, 1996. 相似文献