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排序方式: 共有409条查询结果,搜索用时 15 毫秒
1.
高温超导电力装置一般工作于低磁场情况下,测量超导带材在低场下的临界电流特性非常重要.文中通过自行设计的实验平台,采用四引线法对Y系超导带材低场下的临界电流特性进行了测量,得到了带材临界电流随外加磁场变化的曲线,并与Bi系带材低场下的临界电流特性进行比较.  相似文献   
2.
Highly textured Ni nanowire arrays were fabricated into anodic aluminum oxide(AAO) templates by pulse DC electrodeposition.The applied voltage and pH value of electrolytes were found strongly affecting the microstructure and magnetic properties of Ni nanowire arrays.Low applied potential and pH value both prefer to form polycrystalline fcc Ni nanowires.Increasing the applied potential or pH value favors the Ni [220] texture and even eventually forms the [220] oriented single crystal Ni wires,while exorbitan...  相似文献   
3.
王梦亮  周代翠 《中国物理 C》2011,35(10):935-939
We study the medium modified fragmentation function in high-energy heavy-ion collisions. We show that the ACSX and QW formalisms are equivalent to each other in the high-Q2 limit in both theoretical and numerical aspects.  相似文献   
4.
If we use Littlewood-Paley decomposition, there is no pseudo-orthogonality for Ho¨rmander symbol operators OpS m 0 , 0 , which is different to the case S m ρ,δ (0 ≤δ < ρ≤ 1). In this paper, we use a special numerical algorithm based on wavelets to study the L p continuity of non infinite smooth operators OpS m 0 , 0 ; in fact, we apply first special wavelets to symbol to get special basic operators, then we regroup all the special basic operators at given scale and prove that such scale operator’s continuity decreases very fast, we sum such scale operators and a symbol operator can be approached by very good compact operators. By correlation of basic operators, we get very exact pseudo-orthogonality and also L 2 → L 2 continuity for scale operators. By considering the influence region of scale operator, we get H 1 (= F 0 , 2 1 ) → L 1 continuity and L ∞→ BMO continuity. By interpolation theorem, we get also L p (= F 0 , 2 p ) → L p continuity for 1 < p < ∞ . Our results are sharp for F 0 , 2 p → L p continuity when 1 ≤ p ≤ 2, that is to say, we find out the exact order of derivations for which the symbols can ensure the resulting operators to be bounded on these spaces.  相似文献   
5.
We study the uptake and distribution of transferrin (Tf)-conjugated CdSe/CdS/ZnS quantum dots (QDs) in single living HeLa cells with both fluorescence confocal microscopy and three-dimensional (3D) reconstruction technique. By increasing the co-incubation time or the dosage of QDs-Tf, we find that the uptake of QDs-Tf bioconjugates in the cells increases correspondingly, but with different uptake rates. Additionally, the distribution of QDs-Tf, in single live HeLa cells is time dependent. To our knowledge, this is the first study on quantitatively analyzing the uptake and distribution of bioconjugated QDs in single living cells. Such QDs nanoplatform can be further modified for developing biomedical evaluation tool in cancer diagnosis and targeted drug delivery.  相似文献   
6.
An irreversible light-driven engine is described in this paper, in which the heat transfer between the working fluid and the environment obeys a linear phenomenological heat transfer law [ q ∝Δ(T -1)], with a working fluid composed of the bimolecular reacting system 2SO 3 F■S 2 O 6 F2. Piston trajectories maximizing work output and minimizing entropy generation are determined for such an engine with rate-dependent loss mechanisms of friction and heat leakage. The optimal control theory is applied to determi...  相似文献   
7.
<正>The synthesis and mesomorphic properties of a new class of liquid crystalline cyclotriphosphazenes with rigid cyanostilbene groups and flexible alkoxy groups are reported.The thermal behaviors of cyclotriphosphazene derivatives 5a-5d are studied by the means of differential scanning calorimetry,polarizing optical microscopy.Nematic phases were observed in compounds 5a-5d both on heating and cooling.The clear temperatures of compounds 5a-5d slightly increased with increasing length of terminal alkyl chain.Compounds 5a-5d showed different mesogenic region from minimum 5℃to maximum 142℃.  相似文献   
8.
We provide estimates on the degree of C l GV determinacy ( G is one of Mather’s groups R or K ) of function germs which are defined on analytic variety V and satisfies a non-degeneracy condition with respect to some Newton polyhedron. The result gives an explicit order such that the C l geometrical structure of a function germ is preserved after higher order perturbations, which generalizes the result on C l G triviality of function germs given by M.A.S.Ruas.  相似文献   
9.
刘谦  骆清铭  鲁强  曾绍群 《光子学报》2001,30(12):1449-1452
本文在分析混浊介质对共焦三维扫描图象衰减的基础上,建立了多光子激发荧光扫描的深层图象恢复的数学模型.依照此模型对深层图象进行依赖组织光学参量的恢复,并给出了猪表皮三维扫描成象的恢复图象.  相似文献   
10.
测定了三相逆流离子交换-除CO2联合水处理床中不同截面和不同径向位置的瞬时电导率,探讨了联合水处理床中离子交换的变化规律,研究了运行工况对出水电导率的影响,推导出了这种床中离子交换的速度方程式。  相似文献   
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