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排序方式: 共有103条查询结果,搜索用时 15 毫秒
61.
62.
Yunan Qin Jingpeng Xiong Prof. Dr. Quan Li Prof. Dr. Yuexing Zhang Prof. Dr. Ming-Hua Zeng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(59):e202201821
We present the construction of a M2L4-type metal-organic nanocage featuring four endohedral Feringa's motor motifs and its adaptive encapsulation towards a C60 guest molecule. The structure of the cage, though complicated on the 1H NMR spectrum due to the adoption of mixed ligands, was unambiguously characterized with a combination of ESI-MS, 2D DOSY, 13C NMR and particularly the SAXS technique. The molecular motor within the cage demonstrated similar photophysical properties to the uncoordinated one, indicating the motor's function was not compromised when it was anchored in such a confined nanospace. Furthermore, the nanocage showed good guest encapsulation ability towards C60, and a guest induced-fit behavior of the cage was revealed based on the extensive SAXS analysis and molecular dynamics simulation. The adaptive motorized nanocage reported here represents one of the very few examples of integrating individual motors into a discrete nanoconfined system and offers prospects to achieve its non-equilibrium functions. 相似文献
63.
This paper introduces a deterministic fluid model that approximates the many-server G t /GI/s t +GI queueing model, and determines the time-dependent performance functions. The fluid model has time-varying arrival rate and service capacity, abandonment from queue, and non-exponential service and patience distributions. Two key assumptions are that: (i)?the system alternates between overloaded and underloaded intervals, and (ii)?the functions specifying the fluid model are suitably smooth. An algorithm is developed to calculate all performance functions. It involves the iterative solution of a fixed-point equation for the time-varying rate that fluid enters service and the solution of an ordinary differential equation for the time-varying head-of-line waiting time, during each overloaded interval. Simulations are conducted to confirm that the algorithm and the approximation are effective. 相似文献
64.
65.
Y Yang Y Niu H Hong H Wu Y Zhang JW Engle TE Barnhart J Cai W Cai 《Chemical communications (Cambridge, England)》2012,48(63):7850-7852
A γ-AApeptide-based tracer for positron emission tomography imaging of integrin α(v)β(3) is reported. Despite its shorter sequence and linear nature, this tracer had comparable integrin α(v)β(3) binding affinity to the cyclic arginine-glycine-aspartic acid peptide but significantly higher resistance to enzymatic degradation and better stability. 相似文献
66.
In this paper some basic properties of Orlicz spaces are extended to their dual spaces, and finally, criteria for extreme points in these spaces are given. 相似文献
67.
Ma X Li G Wang M Cheng Y Bai R Chen H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(12):3254-3260
To obtain organic nanowire sensors with high sensitivity and rapid response times, based on the inducement effect of surfactants during in situ polymerization, nanostructured polyaniline composites are obtained by using a chemical oxidation method by adding a small amount of surfactant. A casting method is employed on interdigitated carbon electrodes. The gas sensitivity to a series of chemical vapors is examined at room temperature. The results indicate that polyaniline with regular nanowire structure is obtained when succinic acid is added. The gas sensitivity and response rates of a film with nanowire structure are much better than those of conventional polyaniline films produced by means of organic solution spin coating methods. The film described in this work shows good selectivity to trimethylamine and other related gases and, the reaction being reversible with the use of high-purity nitrogen. 相似文献
68.
Let K be a nonempty closed and convex subset of a real reflexive Banach space X that has weakly sequentially continuous duality mapping J. Let T: K → K be a multivalued non-expansive non-self-mapping satisfying the weakly inwardness condition as well as the condition T(y) = {y} for any y ∈ F(T) and such that for a contraction f: K → K and any t ∈ (0, 1), there exists x t ∈ K satisfying x t ∈ tf(x t ) + (1 ? t)Tx t . Then it is proved that {x t } ? K converges strongly to a fixed point of T, which is also a solution of certain variational inequality. Moreover, the convergence of two explicit methods are also investigated. 相似文献
69.
Yunan Wu Yuchen Peng Long Peng Ling Xu 《Journal of Optimization Theory and Applications》2012,153(2):485-496
The super efficiency of a vector variational inequality is considered in this paper. We show that for both the single and
multiple criteria cases, a network equilibrium model can be recast as super efficient solutions to a kind of variational inequality.
For the network equilibrium model with a vector-valued cost function, we derive the necessary and sufficient condition in
terms of the super efficiency of a vector variational inequality by using the Gerstewitz’s function without any convex assumptions. 相似文献
70.
竖向预应力锚索抗滑桩是一种锚索从桩顶竖向穿过抗滑桩,直接嵌入基岩以下的新型抗滑桩。本文以某滑坡治理工程为例,采用数值模拟方法,研究竖向预应力锚索抗滑桩的内力,从桩长、锚固力、偏心距几个方面对竖向预应力锚索抗滑桩的桩身结构进行优化研究。模拟研究结果表明,其他条件不变时,竖向预应力锚索抗滑桩随着桩长的减小,桩身弯矩最大值变化不大,剪力最大值呈增大趋势; 随锚固力增加,桩身内力最大值均呈先减小后增大的趋势,表明选取合适的锚固力对桩身内力影响很大; 随着锚索偏心距的增大,桩身内力最大值均逐渐减小。优化结果表明,竖向预应力锚索抗滑桩锚固段比悬臂桩减少16.7%,桩身剪力最大值减少31.7%,桩身弯矩最大值减少41.1%。竖向预应力锚索抗滑桩是一种有应用前景的抗滑桩。 相似文献