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991.
Sta?a Milojevi? 《Journal of nanoparticle research》2012,14(1):685-28
This article examines the cognitive evolution and disciplinary diversity of nanoscience/nanotechnology (nano research) as
expressed through the terminology used in titles of nano journal articles. The analysis is based on the NanoBank bibliographic
database of 287,106 nano articles published between 1981 and 2004. We perform multifaceted analyses of title words, focusing
on 100 most frequent words or phrases (terms). Hierarchical clustering of title terms reveals three distinct time periods
of cognitive development of nano research: formative (1981–1990), early (from 1991 to 1998), and current (after 1998). Early
period is characterized by the introduction of thin film deposition techniques, while the current period is characterized
by the increased focus on carbon nanotube and nanoparticle research. We introduce a method to identify disciplinary components of nanotechnology. It shows that the nano research is being carried out in a number of diverse parent disciplines. Currently, only 5% of articles are published in dedicated nano-only journals. We find that some 85% of nano
research today is multidisciplinary. The case study of the diffusion of several nano-specific terms (e.g., “carbon nanotube”)
shows that concepts spread from the initially few disciplinary components to the majority of them in a time span of around
a decade. Hierarchical clustering of disciplinary components reveals that the cognitive content of current nanoscience can
be divided into nine clusters. Some clusters account for a large fraction of nano research and are identified with such parent
disciplines as the condensed matter and applied physics, materials science, and analytical chemistry. Other clusters represent
much smaller parts of nano research, but are as cognitively distinct. In the decreasing order of size, these fields are: polymer
science, biotechnology, general chemistry, surface science, and pharmacology. Cognitive content of research published in nano-only
journals is the closest to nano research published in condensed matter and applied physics journals. 相似文献
992.
Boris?ShapiroEmail author Kouichi?Takemura Milo??Tater 《Communications in Mathematical Physics》2012,311(2):277-300
The well-known Heun equation has the form
ll{Q(z)\frac d2dz2+P(z)\fracddz+V(z)}S(z)=0,\begin{array}{ll}\left\{Q(z)\frac {d^2}{dz^2}+P(z)\frac{d}{dz}+V(z)\right\}S(z)=0,\end{array} 相似文献
993.
994.
Keigo?SuzukiEmail author Nobuhiko?Tanaka Akira?Ando Hiroshi?Takagi 《Journal of nanoparticle research》2012,14(5):863
Size-tuned copper oxide nanoparticles with sizes of 9, 12, and 15 nm were fabricated by laser ablation and on-line size selection
using a differential mobility analyzer at a gas pressure of 666 Pa. The dependence of the particle properties on the in situ
annealing temperatures and selection sizes was investigated. The crystalline phases of the nanoparticles fabricated at temperatures
below 973 K were assigned to monoclinic cupric oxide (CuO) which converted into cubic cuprous oxide (Cu2O) when the annealing temperature was above 1,173 K. This indicates that the crystalline phases can be easily controlled by
changing the annealing temperature. TEM images confirmed that well-crystallized and well-dispersed CuO and Cu2O nanoparticles with narrow size distributions were obtained using this method. This fabrication process is useful and promising
for the future investigation of the intrinsic size-dependent properties of CuO and Cu2O. 相似文献
995.
Simple, accurate and sensitive spectrofluorimetric method has been proposed for the determination of three cephalosporins,
namely; cefixime (cefi), cephalexine (ceph), cefotaxime sodium (cefo) in pharmaceutical formulations. The method is based
on a reaction between cephalosporins with 1, 2-naphthoquinone-4-sulfonic (NQS) in alkaline medium, at pH values of 12.0 for
cefi and 13.0 for ceph and cefo to give highly fluorescent derivatives extracted with chloroform and subsequently measured
at 600,580 and 580 nm after excitation at 520,455 and 490 nm for cefi, ceph and cefo respectively. The optimum experimental
conditions have been studied. Beer’s law is obeyed over the concentrations of 10–35 ng/mL, 10–60 ng/mL and 20–45 ng/mL for
cefi,ceph and cefo, respectively. The detection limits were 2.02 ng/mL, 2.09 ng/mL and 2.30 ng/mL for cefi, ceph and cefo,
respectively, with a linear regression correlation coefficient of 0.9987, 0.9995 and 0.9991 and recoveries in range from 98.5-107.04,
95.17-101.00 and 95.00-109.55% for cefi, ceph and cefo, respectively. This method is simple and can be applied for the determination
of cefi, ceph and cefo in pharmaceutical formulations in quality control laboratories. 相似文献
996.
M. Jubera J. Villarroel A. García-Caba?es M. Carrascosa J. Olivares F. Agullo-López A. Méndez J. B. Ramiro 《Applied physics. B, Lasers and optics》2012,107(1):157-162
The propagation losses (PL) of lithium niobate optical planar waveguides fabricated by swift heavy-ion irradiation (SHI),
an alternative to conventional ion implantation, have been investigated and optimized. For waveguide fabrication, congruently
melting LiNbO3 substrates were irradiated with F ions at 20 MeV or 30 MeV and fluences in the range 1013–1014 cm−2. The influence of the temperature and time of post-irradiation annealing treatments has been systematically studied. Optimum
propagation losses lower than 0.5 dB/cm have been obtained for both TE and TM modes, after a two-stage annealing treatment
at 350 and 375∘C. Possible loss mechanisms are discussed. 相似文献
997.
?smail Aslan 《Applied mathematics and computation》2009,215(8):3140-3147
We extended the (G′/G)-expansion method to two well-known nonlinear differential-difference equations, the discrete nonlinear Schrödinger equation and the Toda lattice equation, for constructing traveling wave solutions. Discrete soliton and periodic wave solutions with more arbitrary parameters, as well as discrete rational wave solutions, are revealed. It seems that the utilized method can provide highly accurate discrete exact solutions to NDDEs arising in applied mathematical and physical sciences. 相似文献
998.
In this paper, we have studied a massive scalar field for a Marder type universe in the context of Lyra and Riemannian geometries. From the exact solutions obtained we show that the massive scalar field does not survive in Lyra and Riemannian geometries for an anisotropic Marder type universe. Therefore we have solved the massless scalar field problem in Lyra and Riemann geometries for two cases. Also we have obtained vacuum solutions for homogeneous and anisotropic Marder space-time in Lyra geometry and the solutions obtained are compared by considering Lyra and Riemann geometries. Finally, some physical and kinematical properties are discussed by using graphics. 相似文献
999.
In this paper we derive some irrationality and linear independence results for series of the form where is either a non-negative integer sequence with υn = o(log n/log log n) or a non-decreasing integer sequence with . 相似文献
1000.
Heng-Yue?Jia Qiao-Yan?Wen Xia?Wu Fei?GaoEmail author Fen-Zhuo?Guo 《International Journal of Theoretical Physics》2012,51(7):2086-2093
We consider the remote preparation of a six-particle cluster-type state using two four-particle GHZ states as the quantum channel in this paper. For the entangled six-particle cluster-type state with real coefficients, a deterministic remote state preparation scheme is proposed. It is shown that, conditioned on the outcome of Alice’s measurement, Bob can successfully prepare the target state by performing an appropriate unitary operation. With regard to the more general six-particle cluster-type state, we give another scheme which can successfully prepare the entangled state with probability 25%. And the probability of success can reach up to 50% or even 1 in some special cases. Furthermore, the classical communication costs in different cases are discussed. 相似文献
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