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11.
I. Neelakanta Reddy Bhargav Akkinepally Venkatesu Manjunath Gaddam Neelima Mogalahalli V. Reddy Jaesool Shim 《Molecules (Basel, Switzerland)》2021,26(23)
In this study, the facile synthesis of SnO2 quantum dot (QD)-garnished V2O5 nanobelts exhibiting significantly enhanced reversible capacity and outstanding cyclic stability for Li+ storage was achieved. Electrochemical impedance analysis revealed strong charge transfer kinetics related to that of V2O5 nanobelts. The SnO2 QD-garnished V2O5 nanobelts exhibited the highest discharge capacity of ca. 760 mAhg−1 at a density of 441 mAg−1 between the voltage ranges of 0.0 to 3.0 V, while the pristine V2O5 nanobelts samples recorded a discharge capacity of ca. 403 mAhg−1. The high capacity of QD-garnished nanobelts was achieved as an outcome of their huge surface area of 50.49 m2g−1 and improved electronic conductivity. Therefore, the as-presented SnO2 QD-garnished V2O5 nanobelts synthesis strategy could produce an ideal material for application in high-performance Li-ion batteries. 相似文献
12.
Ayalvadi Ganesh Sarah Lilienthal D. Manjunath Alexandre Proutiere Florian Simatos 《Queueing Systems》2012,71(3):321-345
In this paper, we analyze the performance of random load resampling and migration strategies in parallel server systems. Clients initially attach themselves to an arbitrary server, but may switch servers independently at random instants of time in an attempt to improve their service rate. This approach to load balancing contrasts with traditional approaches where clients make smart server selections upon arrival (e.g., Join-the-Shortest-Queue policy and variants thereof). Load resampling is particularly relevant in scenarios where clients cannot predict the load of a server before being actually attached to it. An important example is in wireless spectrum sharing where clients try to share a set of frequency bands in a distributed manner. We first analyze the natural Random Local Search (RLS) strategy. Under this strategy, after sampling a new server randomly, clients only switch to it if their service rate is improved. In closed systems, where the client population is fixed, we derive tight estimates of the time it takes under RLS strategy to balance the load across servers. We then study open systems where clients arrive according to a random process and leave the system upon service completion. In this scenario, we analyze how client migrations within the system interact with the system dynamics induced by client arrivals and departures. We compare the load-aware RLS strategy to a load-oblivious strategy in which clients just randomly switch server without accounting for the server loads. Surprisingly, we show that both load-oblivious and load-aware strategies stabilize the system whenever this is at all possible. We use large-system asymptotics to characterize system performance, and augment this with simulations, which suggest that the average client sojourn time under the load-oblivious strategy is not considerably reduced when clients apply smarter load-aware strategies. 相似文献
13.
A blend of cellulose acetate phthalate with poly (methyl methacrylate) has been developed by reinforcing it with silane-treated nanoclay. In order to enhance interactions between the nanoclay and blend components, maleic anhydride was added as the coupling agent. The mechanical properties were enhanced and were further analyzed by theoretical models. The thermal properties and water absorption characteristics were also assessed. 相似文献
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The present study deals with the static pressure and mean velocity fields generated due to the mixing of two plane turbulent
jets in a confined passage. Four different impingement angles, viz., 15, 30, 45 and 60 degrees, have been investigated. It
is found that the inlet angle is the most important parameter governing the extent of the central recirculation zone, the
wall recirculation zones, the position of the confluence point and the distance required for complete mixing. The rate of
decay of the maximum velocity is very rapid for inlet angles exceeding 45 degrees. 相似文献
17.
A study of the hyperfine interaction in the ESR of Cu-Cu pairs in single crystals of copper diethyldithiocarbamate as a function
of temperature has shown distinct differences in the hyperfine structure in the two fine structure transitions at 20 K, the
spectrum not having the same hyperfine intensity pattern in the low field fine structure transition in contrast to that of
the high field transition. The details of the structure of both the fine structure transitions in the 20 K spectrum have now
been explained by recognizing the fact that the mixing of the nuclear spin states caused by the anisotropic hyperfine interaction
affects the electron spin states | + 1 > and | −> differently. This has incidentally led to a determination of the sign ofD confirming the earlier model. The anomalous hyperfine structure is found to become symmetric at 77 K and 300 K. It is proposed
that the reason for this lies in the dynamics of spin-lattice interaction which limits the lifetime of the spin states in
each of the electronic levels | − 1 >, | 0 > and | + 1 > The estimate of spin-lattice relaxation time agrees with those indicated
from other studies. The model proposed here for the hyperfine interaction of pairs in the electronic triplet state is of general
validity. 相似文献
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