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61.
Casein is well known as a good protein emulsifier and beta-casein is the major component of casein and commercial sodium caseinate. Dye affinity adsorption is increasingly used for protein separation. beta-Casein adsorption onto Reactive Red 120 attached magnetic poly(2-hydroxyethyl methacrylate) (m-PHEMA) beads was investigated in this work. m-PHEMA beads (80-120 microm in diameter) were produced by dispersion polymerization. The dichlorotriazine dye Reactive Red 120 was attached covalently as a ligand. The dye attached beads, having a swelling ratio of 55% (w/w) and carrying different amounts of Reactive Red 120 (9.2 micromol . g(-1)-39.8 micromol . g(-1)), were used in beta-casein adsorption studies. The effects of the initial concentration, pH, ionic strength and temperature on the adsorption efficiency of dye attached beads were studied in a batch reactor. The non-specific adsorption on the m-PHEMA beads was 1.4 mg . g(-1). Reactive Red 120 attachment significantly increased the beta-casein adsorption up to 37.3 mg . g(-1). More than 95.4% of the adsorbed beta-casein was desorbed in 1 h in a desorption medium containing 1.0 M KSCN at pH 8.0. We concluded that Reactive Red 120 attached m-PHEMA beads can be applied for beta-casein adsorption without significant losses in the adsorption capacities. 相似文献
62.
S(1D)+H2→SH+H reaction at zero total angular momentum has been studied by using a time-dependent quantum real wave packet method. State-to-state and state-to-all reactive scattering probabilities for a broad range of energy are calculated. The probabilities show many sharp peaks that ascribed to reactive scattering resonances. The density plots of the wave function shows that the reaction presents a pure insertion pathway. 相似文献
63.
This study demonstrates an approach to generate reinforcement in thermosetting polymers through crystal growth of crystallizable solvents. Emphasis is to identify the reaction conditions, which lead to suitable reinforcement in selected compounds. Crystallization behavior and miscibility of dimethylsulfone (DMS) in diglycidylether of bisphenol‐A epoxy monomer was investigated. Small angle laser scattering and optical microscopy were utilized to monitor phase separation and crystallization of DMS at different isothermal conditions during the cure process. It is shown that DMS crystals grow anisotropically to form faceted geometries and demonstrate possible structures to anchor into the epoxy matrix. The growth mechanism and the agility of crystals are shown to be affected by the cure reaction as well as depth of supercooling. A completely cured sample with 15 wt % DMS shows a broad map of rich morphologies from nanoscale particles to uniformly distributed macroscale, discontinuous fiber‐like crystals generated only by altering the curing conditions. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 840–849, 2010 相似文献
64.
Sinan Ünver 《Mathematische Nachrichten》2010,283(9):1353-1357
Based on the (not yet fully understood analogy) between irregular connections and wild ramification, we define a purely irregular fundamental group for complex algebraic varieties and prove some results about this fundamental group which are analogous to the p‐adic étale fundamental group of algebraic varieties over fields of characteristic p (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
65.
针对常规蓄电池放电采用可变电阻器进行性能测试所引起的准确度低、可靠性差、操作困难等问题,文中提出了一种并网充放电的电池性能检测方式。通过对铅酸蓄电池中电荷量、温度、电流微分表达式的分析,建立由主反应支路和寄生支路组成的三阶等效数学模型。电池的充放电采用阶跃信号触发Buck-Boost双向变换电路开关通断的恒流模式。逆变电路采用电压电流双闭环控制,并经电感滤波后并入模拟电网。在MATLAB/Simulink软件上搭建的仿真模型验证结果表明蓄电池各项性能指标和并网电流动态响应良好,证明了文中所提方法的有效性和环保性。 相似文献
66.
In this note, we study the action of finite groups of symplectic automorphisms on K3 surfaces which yield quotients birational
to generalized Kummer surfaces. For each possible group, we determine the Picard number of the K3 surface admitting such an
action and for singular K3 surfaces we show the uniqueness of the associated abelian surface.
Received: 9 April 1998 / Revised version: 17 July 1998 相似文献
67.
68.
Sinan Ünver 《Journal of Number Theory》2004,108(1):111-156
Let X be the projective line minus 0,1, and ∞ over . The aim of the following is to give a series representations of the p-adic multi-zeta values in the depth two quotient. The approach is to use the lifting of the frobenius which is not a good choice near 1, but which gives simple formulas away from 1, and to relate the action of frobenius on the de Rham path from 0 to ∞ and on the one from 0 to 1. Also some relations between the p-adic multi-zeta values of depth two are obtained. 相似文献
69.
Wireless Information Delivery Environment (WIDE) is a distributed data dissemination system, which uses IEEE 802.11b technology.
WIDE aims to deliver popular information services to registered mobile clients in WLAN hot spots. Data delivery is based on
broadcasting and multicasting to provide scalability and efficient use of the wireless channel. Reliability is assured with
a combination of Forward Error Correction (FEC), data carousel, and ARQ techniques. This paper presents the proposed system
architecture with the details of reliable and secure data dissemination mechanisms. Functional evaluation of the proposed
system and mechanisms on the implemented prototype are also included in this paper.
This work is partially supported by the State Planning Organization of Turkey under the grant number 98K120890, and by the
Bogazici University Research Projects under the grant number 02A105D. A shorter version of this paper was presented in WONS
2004 in Madonna di Campiglio, Italy.
Sinan Isik received the B.S. degree in mathematics, and the M.S. degree in computer engineering from Bogazici University, Istanbul,
Turkey in 1999 and 2003, respectively. He is currently working toward for the PhD degree in computer engineering in the same
university. His research interests include wireless communication, wireless ad-hoc networks and wireless sensor networks.
Mehmet Yunus Donmez received his B.S. degree from Mathematics Department in 1999 and his MS degree from the Computer Engineering Department of
Bogazici University, Istanbul, Turkey in 2003. He is currently studying for his PhD degree in computer engineering. His research
interests are wireless networks and content delivery systems, along with QoS, multicasting and fairness issues in MANETs.
Cem Ersoy received his BS and MS degrees in electrical engineering from Bogazici University, Istanbul, in 1984 and 1986, respectively.
He worked as an R&D engineer in NETAS A.S. between 1984 and 1986. He received his PhD in electrical engineering from Polytechnic
University, Brooklyn, New York in 1992. Currently, he is a professor and department head in the Computer Engineering Department
of Bogazici University. His research interests include performance evaluation and topological design of communication networks,
wireless communications and mobile applications. Dr. Ersoy is a Senior Member of IEEE. 相似文献
70.
Sinan Yildirim Sumeetpal S. Singh Arnaud Doucet 《Journal of computational and graphical statistics》2013,22(4):906-926
Changepoint models are widely used to model the heterogeneity of sequential data. We present a novel sequential Monte Carlo (SMC) online expectation–maximization (EM) algorithm for estimating the static parameters of such models. The SMC online EM algorithm has a cost per time which is linear in the number of particles and could be particularly important when the data is representable as a long sequence of observations, since it drastically reduces the computational requirements for implementation. We present an asymptotic analysis for the stability of the SMC estimates used in the online EM algorithm and demonstrate the performance of this scheme by using both simulated and real data originating from DNA analysis. The supplementary materials for the article are available online. 相似文献