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991.
Z.X. CaoY.L. Ye J. XiaoL.H. Lv D.X. JiangT. Zheng H. HuaZ.H. Li X.Q. LiY.C. Ge J.L. LouR. Qiao Q.T. LiH.B. You R.J. ChenD.Y. Pang H. SakuraiH. Otsu M. NishimuraS. Sakaguchi H. BabaY. Togano K. YonedaC. Li S. WangH. Wang K.A. LiT. Nakamura Y. NakayamaY. Kondo S. DeguchiY. Satou K. Tshoo 《Physics letters. [Part B]》2012,707(1):46-51
We report for the first time the discrimination of the core fragment knockout and valence nucleon knockout reaction mechanisms at medium energy range, by the use of the recoil proton tagging technique. Intense 8He beams at 82.3 MeV/u were supplied by the RIPS beam line at RIKEN, and impinged on both hydrogen and carbon targets. Recoil protons were detected in coincidence with the forward moving core fragments and neutrons. The core fragment knockout mechanism is identified through the polar angle correlation and checked by various kinematics relations. This mechanism may be used to extract the cluster structure information of unstable nuclei. On the other hand, with the selection of the tagged valence nucleon knockout mechanism, a narrower peak of 7He ground state is obtained. The extracted neutron spectroscopic factor Sn=0.512(18) is relatively smaller than the no-tagged one, and is in good agreement with the prediction of ab initio Green?s function Monte Carlo calculations. 相似文献
992.
Huiling Li Peter Y. H. Pang Mingxin Wang 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2012,89(1):295-311
We study the existence, uniqueness, and asymptotic behavior of blow-up solutions for a general quasilinear elliptic equation
of the type −Δ
p
u = a(x)u
m
−b(x)f(u) with p > 1 and 0 < m < p−1. The main technical tool is a new comparison principle that enables us to extend arguments for semilinear equations to
quasilinear ones. Indeed, this paper is an attempt to generalize all available results for the semilinear case with p = 2 to the quasilinear case with p > 1. 相似文献
993.
Zhi Xiao Xianglei Yang Qing Niu Yuanxiang Dong Ke Gong Sisi Xia Ying Pang 《Applied Mathematical Modelling》2012
Soft set theory, initiated by Molodtsov, is a general mathematical tool for dealing with uncertain problems. In this paper, we first point out that the similarity measure in a previous paper by Majumdar and Samanta [P. Majumdar, S.K. Samanta, Generalized fuzzy soft sets, Comput. Math. Appl. 59 (2010) 1425–1432] is limited by two counterexamples. To deal with the problems of subjective evaluation and uncertain knowledge, this paper proposes the concept of D–S generalized fuzzy soft sets by combining Dempster–Shafer theory of evidence and generalized fuzzy soft sets. We study some of its operations and basic properties, and the relationship between generalized fuzzy soft sets and D–S generalized fuzzy soft sets are introduced. Then we propose the concept of the similarity between two D–S generalized fuzzy soft sets. At last, we present a new method of evaluation based on D–S generalized fuzzy soft sets and apply it into a medical diagnosis problem. 相似文献
994.
C.H. Jeffrey Pang 《Nonlinear Analysis: Theory, Methods & Applications》2012,75(3):1348-1361
We extend Robinson’s and Ledyaev and Zhu’s implicit multifunction theorems using the language of generalized derivatives with positively homogeneous maps, allowing us to obtain results that more closely resemble the classical (single-valued) implicit function theorem. We highlight that using linear openness instead of metric regularity gives simpler proofs and stronger results. As part of our analysis, we study perturbations of generalized linear openness and metric regularity. Finally, we discuss how our methods may also be adapted to study generalized calmness. 相似文献
995.
996.
We report on guided-wave second-harmonic generations in nonlinear Nd:YCa4O(BO3)3 (Nd:YCOB) optical waveguides that are produced by the low-fluence swift Ar8+ ion irradiation. The guided-wave second harmonics are realized through the frequency doubling and the self-frequency-doubling of the waveguides under the optical pumps at wavelengths of 1064 and 810 nm, respectively. By virtue of the self-frequency-conversion configuration, the Nd:YCOB waveguides are promising candidates as novel, compact, miniature green laser sources. 相似文献
997.
Sonocatalytic degradation of various organic dyes (Congo Red, Reactive Blue 4, Methyl Orange, Rhodamine B and Methylene Blue) catalyzed by powder and nanotubes TiO2 was studied. Both catalysts were characterized using transmission electron microscope (TEM), surface analyzer, Raman spectroscope and thermal gravimetric analyzer (TGA). Sonocatalytic activity of powder and nanotubes TiO2 was elucidated based on the degradation of various organic dyes. The former catalyst was favorable for treatment of anionic dyes, while the latter was more beneficial for cationic dyes. Sonocatalytic activity of TiO2 nanotubes could be up to four times as compared to TiO2 powder under an ultrasonic power of 100 W and a frequency of 42 kHz. This was associated with the higher surface area and the electrostatic attraction between dye molecules and TiO2 nanotubes. Fourier transform-infrared spectrometer (FT-IR) was used to identify changes that occurred on the functional group in Rhodamine B molecules and TiO2 nanotubes after the reaction. Sonocatalytic degradation of Rhodamine B by TiO2 nanotubes apparently followed the Langmuir-Hinshelwood adsorption kinetic model with surface reaction rate of 1.75 mg/L min. TiO2 nanotubes were proven for their high potential to be applied in sonocatalytic degradation of organic dyes. 相似文献
998.
环氧丙烷是一种重要的化工中间体,广泛应用于化工、医药、食品、轻工等行业。环氧丙烷的传统工业生产方法--氯醇法和共氧化法存在着很多缺点,而最新开发的H2O2氧化法则存在催化剂寿命短、H2O2利用率低等问题没有根本解决。本文对环氧丙烷更为有前景的生产方法--以分子氧为氧源的气相选择性氧化丙烯的研究进展进行了总结,着重介绍了丙烯气相环氧化反应中的金、银、铜、铋-钼、钒、熔融盐催化剂以及其他以氧气为氧源的金属催化剂的研究进展,同时对丙烯气相氧化过程中涉及到的金催化剂的Ti活性位机理,铜、银催化剂上的金属环氧化中间物机理,银及其他金属的自由基机理作了相应的介绍。 相似文献
999.
The blue-shifted supercontinuum generation in a photonic crystal fiber pumped by high peak power femtosecond pulses with wavelength located in the anomalous dispersion region is investigated experimentally and numerically. The formation of a blue-shifted enhanced supercontinuum due to the pulse collapse is demonstrated. The process of the pulse collapse is measured by using the grating-eliminated no-nonsense observation of ultrafast incident laser light e-fields technique (GRENOUILLE). Numerical simulations in spectral and temporal domains are conducted. The data from numerical simulations are in good agreement with the experimental results. Our experimental results and numerical simulations show that the pulse collapse is the determining factor in the generation of blue-shifted supercontinuum. 相似文献
1000.
The effect of spin-orbit coupling on magnetoresistance in nonmagnetic organic semiconductors 下载免费PDF全文
We investigated the effect of spin-orbit coupling on magnetoresistance in nonmagnetic organic semiconductors.A Lorentz-type magnetoresistance is obtained from spin-orbit coupling-dependent spin precession under the condition of a space-charge-limited current.The magnetoresistance depends on the initial spin orientation of the electron with respect to the hole in electron-hole pairs,and the increasing spin-orbit coupling slows down the change in magnetoresistance with magnetic field.The field dependence,the sign and the saturation value of the magnetoresistance are composite effects of recombination and dissociation rate constants of singlet and triplet electron-hole pairs.The simulated magnetoresistance shows good consistency with the experimental results. 相似文献