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261.
Nasim Baimani Parviz Aberoomand Azar Syed Waqif Husain Homayon Ahmad Panahi Ali Mehramizi 《Journal of separation science》2019,42(7):1468-1476
We developed an approach for the use of polyester dendrimer during the imprinting process to raise the number of recognized sites in the polymer matrix and improve its identification ability. Photoresponsive molecularly imprinted polymers were synthesized on modified magnetic nanoparticles involving polyester dendrimer which uses the reactivity between allyl glycidyl ether and acrylic acid for the high‐yielding assembly by surface polymerization. The photoresponsive molecularly imprinted polymers were constructed using methylprednisoloneacetate as the template, water‐soluble azobenzene involving 5‐[(4, 3‐(methacryloyloxy) phenyl) diazenyl] dihydroxy aniline as the novel functional monomer, and ethylene glycol dimethacrylate as the cross‐linker. Through the evaluation of a series of features of spectroscopic and nano‐structural, this sorbent showed excellent selective adsorption, recognition for the template, and provided a highly selective and sensitive strategy for determining the methylprednisoloneacetate in real and pharmaceutical samples. In addition, this sorbent according to good photo‐responsive features and specific affinity to methylprednisoloneacetate with high recognition ability, represented higher binding capacity, a more extensive specific area, and faster mass transfer rate than its corresponding surface molecularly imprinted polymer. 相似文献
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We study Einstein gravity in a finite spatial region. By requiring a well-defined variational principle, we identify all local boundary conditions, derive surface observables, and compute their algebra. The observables arise as induced surface terms, which contribute to a non-vanishing Hamiltonian. Unlike the asymptotically flat case, we find that there are an infinite number of surface observables. We give a similar analysis for SU(2) BF theory. 相似文献
264.
Optimality conditions and duality in subdifferentiable multiobjective fractional programming 总被引:3,自引:0,他引:3
C. R. Bector S. Chandra I. Husain 《Journal of Optimization Theory and Applications》1993,79(1):105-125
Fritz John and Kuhn-Tucker necessary and sufficient conditions for a Pareto optimum of a subdifferentiable multiobjective fractional programming problem are derived without recourse to an equivalent convex program or parametric transformation. A dual problem is introduced and, under convexity assumptions, duality theorems are proved. Furthermore, a Lagrange multiplier theorem is established, a vector-valued ratio-type Lagrangian is introduced, and vector-valued saddle-point results are presented.The authors are thankful to the referees and Professor P. L. Yu for their many useful comments and suggestions which have improved the presentation of the paper.The first author is thankful to the Natural Science and Engineering Research Council of Canada for financial support through Grant No. A-5319. The authors are also thankful to the Dean's Office, Faculty of Management, University of Manitoba, for the financial support provided for the third author's visit to the Faculty. 相似文献
265.
J F Mahoney J Perel S A Ruatta P A Martino S Husain T D Lee 《Rapid communications in mass spectrometry : RCM》1991,5(10):441-445
A new ion desorption method is described that utilizes a primary beam of massive, multiply charged cluster ions to generate secondary ions of peptides in a glycerol matrix. The massive cluster ion beam is generated via electrohydrodynamic emission using a 1.5 M solution of ammonium acetate in 30% aqueous glycerol. Negative ion spectra of peptides obtained using this technique show greatly decreased relative intensities for fragment ions and 'chemical noise' background when compared to spectra obtained using a xenon atom primary beam. The near absence of fragments derived from radiation damage to the sample solution is attributed to the impact of primary particles with energies less than 1 eV/nucleon. 相似文献
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S Chandra B.D Craven I Husain 《Journal of Mathematical Analysis and Applications》1985,107(1):122-131
Optimality conditions, duality and converse duality results are obtained for a class of continuous programming problems with a nondifferentiable term in the integrand of the objective function. The proofs are based on a Fritz John theorem for constrained optimization in abstract spaces. The results generalize various well-known results in variational problems with differentiable functions, and also give a dynamic analogue of certain nondifferentiable programming problems. 相似文献