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101.
学术性是大学的本质所在,大学的核心竞争力本质上是基于知识资本的学术竞争力。大学学术竞争力是大学人力、科教、文化、组织与社会等五种(知识)资本学术竞争力的整体协同涌现,其自组织演进,既受到大学内部因素的协同作用,又离不开外部环境作用的影响。 相似文献
102.
103.
文章在假想的“磁荷世界”中修改了麦克斯韦方程组和洛伦兹力公式.由磁的库仑定律出发,并根据磁荷与电荷产生的电磁场的等效性,得到真空中静磁场的高斯定理和环路定理.仿照“电荷世界”中的电流定义了磁流强度,又根据磁场的相对论变换,由毕奥—萨伐尔定律和法拉第电磁感应定律得到稳恒电场D的高斯定理和环路定理. 相似文献
104.
105.
106.
V. Arnold 《Bulletin of the Brazilian Mathematical Society》2003,34(1):1-42
This article concerns the arithmetics of binary quadratic
forms with integer coefficients, the De Sitters world and the
continued fractions.Given a binary quadratic forms with integer coefficients,
the set of values attaint at integer points is always a
multiplicative tri-group. Sometimes it is a semigroup (in such
case the form is said to be perfect). The diagonal forms are
specially studied providing sufficient conditions for their
perfectness. This led to consider hyperbolic reflection groups
and to find that the continued fraction of the square root of a
rational number is palindromic.The relation of these arithmetics with the geometry of the
modular group action on the Lobachevski plane (for elliptic
forms) and on the relativistic De Sitters world (for the
hyperbolic forms) is discussed. Finally, several estimates of
the growth rate of the number of equivalence classes versus the
discriminant of the form are given.Partially supported by RFBR, grant 02-01-00655. 相似文献
107.
Using simulated annealing, we examine a bipartitioning of small worlds obtained by adding a fraction of randomly chosen links to a one-dimensional chain or a square lattice. Models defined on small worlds typically exhibit a mean-field behavior, regardless of the underlying lattice. Our work demonstrates that the bipartitioning of small worlds does depend on the underlying lattice. Simulations show that for one-dimensional small worlds, optimal partitions are finite size clusters for any fraction of additional links. In the two-dimensional case, we observe two regimes: when the fraction of additional links is sufficiently small, the optimal partitions have a stripe-like shape, which is lost for a larger number of additional links as optimal partitions become disordered. Some arguments, which interpret additional links as thermal excitations and refer to the thermodynamics of Ising models, suggest a qualitative explanation of such a behavior. The histogram of overlaps suggests that a replica symmetry is broken in a one-dimensional small world. In the two-dimensional case, the replica symmetry seems to hold, but with some additional degeneracy of stripe-like partitions. 相似文献
108.
109.
分析了中学物理实验教学现状,指出大学与中学物理实验教学衔接存在的问题,根据现代教育理论,提出了大学一年级物理实验教学的对策。 相似文献
110.
The well known “real-life examples” of small world graphs, including the graph of binary relation: “two persons on the earth
know each other” contains cliques, so they have cycles of order 3 and 4. Some problems of Computer Science require explicit
construction of regular algebraic graphs with small diameter but without small cycles. The well known examples here are generalised
polygons, which are small world algebraic graphs i.e. graphs with the diameter d≤clog
k−1(v), where v is order, k is the degree and c is the independent constant, semiplanes (regular bipartite graphs without cycles of order 4); graphs
that can be homomorphically mapped onto the ordinary polygons. The problem of the existence of regular graphs satisfying these
conditions with the degree ≥k and the diameter ≥d for each pair k≥3 and d≥3 is addressed in the paper. This problem is positively solved via the explicit construction. Generalised Schubert cells
are defined in the spirit of Gelfand-Macpherson theorem for the Grassmanian. Constructed graph, induced on the generalised
largest Schubert cells, is isomorphic to the well-known Wenger’s graph. We prove that the family of edge-transitive q-regular Wenger graphs of order 2q
n
, where integer n≥2 and q is prime power, q≥n, q>2 is a family of small world semiplanes. We observe the applications of some classes of small world graphs without small
cycles to Cryptography and Coding Theory. 相似文献