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排序方式: 共有349条查询结果,搜索用时 31 毫秒
341.
B. Brennan M. MilojevicC.L. Hinkle F.S. Aguirre-TostadoG. Hughes R.M. Wallace 《Applied Surface Science》2011,257(9):4082-4090
The passivation of III-V semiconductor materials with sulphur is widely reported to reduce interface state defects and improve semiconductor device performance. The most common approach utilises ammonium sulphide ((NH4)2S), however there are wide variations in the reported processing parameters involved in this procedure. This study provides a comprehensive review of the various parameters used as well as determining the optimal processing conditions in terms of sample pre-treatments, temperature of the (NH4)2S solution, length of time the sample is in the solution and (NH4)2S concentration, by measuring the level of residual native oxides and surface roughness by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), respectively. 相似文献
342.
This paper discusses the dynamic behaviour of a nonlinear two degree-of-freedom system consisting of a harmonically excited linear oscillator weakly connected to a nonlinear attachment having linear and cubic restoring forces. The effects of the system parameters on the shape of the frequency-response curve are investigated, in particular those yielding the appearance and disappearance of outer and inner detached resonance curves. In contrast to the case when the linear stiffness of the attachment is zero, it is found that multivaluedness occurs at low frequencies as the resonant peak bends to the right. It is also found that as the coefficient of the linear term increases, the range of parameters yielding detached curves reduces. Compared to the case when the attached system has no linear stiffness term, this range of parameters corresponds to smaller values of the damping and nonlinear coefficients. Approximate analytical expressions for the jump-up and jump-down frequencies of the system under investigation are also derived. 相似文献
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344.
Li Lan Juste Ted Brennan Joseph Cheng Chuangxun Han Deguang 《Journal of Fourier Analysis and Applications》2019,25(1):86-100
Journal of Fourier Analysis and Applications - We consider the problem of characterizing projective representations that admit frame vectors with the maximal span property, a property that allows... 相似文献
345.
Chen JJ Struk KN Brennan AB 《Langmuir : the ACS journal of surfaces and colloids》2011,27(22):13754-13761
A thiol-ene polymerization was accomplished on silicate glass slides to graft a series of homopolymers and copolymers using 3-(mercaptopropyl)trimethoxysilane (MTS) as both a silane coupling agent and initiator. MTS was initially covalently bonded to an acid cleaned glass surface via a classical sol-gel reaction. Poly(acrylic acid) (PAA), poly(acrylamide) (PAAm), poly(methyl acrylate) (PMA), poly(acrylamido-2-methyl-propanesulfonic acid) (PAMPS), and the copolymer poly(AA-co-AAm-co-MA-co-AMPS) were grafted from the thiol group of MTS. The surface chemistry of the MTS modified slides and polymer grafts was characterized with attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). Surface texture was evaluated with tapping mode atomic force microscopy (TM-AFM). The Owens-Wendt-Kaelble (OWK) and Lifshitz-van der Waals acid-base (LW-AB) methods were used to evaluate surface energies by sessile drop contact angle method. The synthetic approach demonstrated a facile, rapid method for grafting to glass surfaces. 相似文献
346.
Operational stochastic cooling of 100 GeV/nucleon gold beams has been achieved in the BNL Relativistic Heavy-Ion Collider. We discuss the physics and technology of the longitudinal cooling system and present results with the beams. A simulation algorithm is described and shown to accurately model the system. 相似文献
347.
Dr. M. Monsur Ali Prof. Dr. Manali Mukherjee Katherine Radford Zil Patel Prof. Dr. Alfredo Capretta Prof. Dr. Parameswaran Nair Prof. Dr. John D. Brennan 《Angewandte Chemie (International ed. in English)》2023,62(38):e202307451
The first protein-binding allosteric RNA-cleaving DNAzyme (RCD) obtained by direct in vitro selection against eosinophil peroxidase (EPX), a validated marker for airway eosinophilia, is described. The RCD has nanomolar affinity for EPX, shows high selectivity against related peroxidases and other eosinophil proteins, and is resistant to degradation by mammalian nucleases. An optimized RCD was used to develop both fluorescence and lateral flow assays, which were evaluated using 38 minimally processed patient sputum samples (23 non-eosinophilic, 15 eosinophilic), producing a clinical sensitivity of 100 % and specificity of 96 %. This RCD-based lateral flow assay should allow for rapid evaluation of airway eosinophilia as an aid for guiding asthma therapy. 相似文献
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