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921.
Solvent and electric field dependence of the photocurrent generation in donor:acceptor blend system 下载免费PDF全文
This paper reports that the blend films of poly
(2-methoxy-5-(2'-ethyl-hexyloxy)-p-phenylene vinylene) (MEH-PPV)
and N,N'-bis(1-ethylpropyl)-3,4: 9,10-perylene bis
(tetracarboxyl diimide) (EP-PDI) with the weight ratio of 1:2.5
have been prepared by spin-coating from chloroform (CF) and
chlorobenzene (CB) solutions respectively. The absorption
spectra and the morphology of the blend films show that large
crystal-like EP-PDI aggregates are formed in film prepared from
CB solution, which corresponds to a new absorption shoulder near
590nm, while there is no shoulder around 590\,nm in the
UV--Vis absorption spectra of the blend film from CF solution.
The electric-field dependence spectra of the photocurrent
generation quantum yield of the film from CB solution shows that
at weak electric field the EP-PDI aggregates act as more
efficient sensitizers, but at strong electric field the quantum
yields become almost invariable over the entire spectral range
no matter what the state of EP-PDI, monomer or aggregate. At
strong electric field, the photocurrent generation yields of
both films from CF and CB solution saturate and their yield
spectra become spectrally similar, mentioning that at strong
electric field the photoexcitons dissociate efficiently and the
free charges are collected by the electrodes almost completely. 相似文献
922.
Cao Li-ke Liang Hong Peng Dan-tao Yang Tao Yue Rui-hong 《Frontiers of Physics in China》2007,2(2):234-237
Gaudin model is a very important integrable model in both quantum field theory and condensed matter physics. The integrability
of Gaudin models is related to classical r-matrices of simple Lie algebras and semi-simple Lie algebra. Since most of the constructions of Gaudin models works concerned
mainly on rational and trigonometric Gaudin algebras or just in a particular Lie algebra as an alternative to the matrix entry
calculations often presented, in this paper we give our calculations in terms of a basis of the typical Lie algebra, A
n
, B
n
, C
n
, D
n
, and we calculate a classical r-matrix for the elliptic Gaudin system with spin.
相似文献
923.
Yang J Makasyuk I Kevrekidis PG Martin H Malomed BA Frantzeskakis DJ Chen Z 《Physical review letters》2005,94(11):113902
We report the first observation of stationary necklacelike solitons. Such necklace structures were realized when a high-order vortex beam was launched appropriately into a two-dimensional optically induced photonic lattice. Our theoretical results obtained with continuous and discrete models show that the necklace solitons resulting from a charge-4 vortex have a pi phase difference between adjacent "pearls" and are formed in an octagon shape. Their stability region is identified. 相似文献
924.
This paper performs a numerical simulation of concentric-ring discharge structures within the scope of a two-dimensional diffusion--drift model at atmospheric pressure between two parallel circular electrodes covered with thin dielectric layers. With a relative high frequency the discharge structures present different appearances of ring structures within different radii in time due to the evolvement of the filaments. The spontaneous electron density distributions help understanding the formation and development of self-organized discharge structures. During a cycle the electron avalanches are triggered by the electric field strengthened by the feeding voltage and the residual charged particles on the barrier surface deposited in the previous discharges. The accumulation of charges is shown to play a dominant role in the generation and annihilation of the discharge structures. Besides, the rings split and unify to bring and annihilate rings which form a new discharge structure. 相似文献
925.
926.
采用超分子单双迭代(包括非迭代三重激发)耦合簇理论CCSD(T)方法,选择由原子中心高斯函数和高斯键函数3s3p2d1f组成的大基组,计算了He-H2(D2,T2)碰撞体系的H2分子取不同键长时的相互作用势能面.运用Tang-Toennies势模型和非线性最小二乘法拟合构造了He与同位素分子H2(D2,T2)在质心坐标系下的振转相互作用势.通过密耦计算得
关键词:
高斯键函数
Tang-Toennies势函数
分波截面
碰撞参数 相似文献
927.
Passive harmonic mode-locking of dissipative solitons is demonstrated in all-normal dispersion Yb-doped fibre lasers.A difference equation model of the mode-locked fibre lasers is adopted to simulate the intra-cavity nonlinear dynamics.Hysteresis phenomena around the mode-locking threshold,and the effect of introducing linear phase bias are discussed.The passive harmonic mode-locking as one kind of multipulsing operations is revealed.Moreover,the simulation shows the bistability between multipulsing and single-pulse or period multiplication. 相似文献
928.
Wan WQ Pan QH Jia GJ Xu YZ Lai GQ Liu SX Chen J Yang LM Zhang YF Weng SF Wu JG 《光谱学与光谱分析》2011,31(2):353-356
采用傅里叶变换衰减全反射中红外光谱法检测了24例液氮冻存的脑膜瘤离体样品(其中良性肿瘤12例,有恶性倾向的肿瘤12例),对得到的红外光谱进行整理分析,发现不同类型脑膜瘤组织(如纤维型脑膜瘤和内皮型脑膜瘤)的红外光谱存在着差异,并且同一种类型的脑膜瘤组织,其恶性倾向的程度不同,他们的红外光谱也表现出较为明显的区别,因此,我们可以从各个特征吸收峰的峰位、峰形及峰强等信息的变化来区分脑膜瘤,并可以初步鉴别脑膜瘤的性质;研究结果发现,通过某些特征吸收峰(如1 160cm-1)峰位的变化来鉴别脑膜瘤的性质与病理诊断结果的符合率大于85%,说明傅里叶变换衰减全反射中红外光谱法有可能发展成为一种对样品无损伤、快速的脑肿瘤诊断新方法。 相似文献
929.
Surface modification of polytetrafluoroethylene film using single liquid electrode atmospheric- pressure glow discharge 下载免费PDF全文
Polytetrafluoroethylene films are treated by room temperature helium atmospheric pressure plasma plumes, which are generated with a home-made single liquid electrode plasma device. After plasma treatment, the water contact angle of polytetrafluoroethylene film drops from 114°to 46°and the surface free energy increases from 22.0 mJ/m2 to 59.1 mJ/m2. The optical emission spectrum indicates that there are reactive species such as O2+ , O and He in the plasma plume. After plasma treatment, a highly crosslinking structure is formed on the film surface and the oxygen element is incorporated into the film surface in the forms of -C-O-C-, -C=O, and -O-C=O groups. Over a period of 10 days, the contact angle of the treated film is recovered by only about 10 , which indicates that the plasma surface modification is stable with time. 相似文献
930.
Lin Wang Heqing Yang Hua Zhao Ru Yu Shi Liu Bao Bin Liu 《Applied Physics A: Materials Science & Processing》2011,102(1):61-68
The present work reports on novel four-layer thermally driven piezoresistive cantilevers implemented in one- and two-dimensional
arrays for parallel proximity scanning. There, the heater (metallic meander), the piezoresistive deflection sensor, and the
metal actuation film with significantly higher thermal expansion coefficient make up separate layers. Actuation efficiency
and cross-talk of the novel cantilever design are studied and compared with two recent designs: thin metallic film and ion-implanted
heater. The novel actuator, integrated on a 240 μm long and 3 μm thick silicon cantilever and supplied by V
dc=1 V enables deflections up to 5 μm of the AFM-tip with an actuation efficiency of about 170 nm/mW and suppressed cross-talk
between actuator and sensor. 相似文献