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排序方式: 共有489条查询结果,搜索用时 125 毫秒
421.
Truong Xuan Duc Ha 《Journal of Mathematical Analysis and Applications》2006,316(1):346-356
In this paper we present two set-valued variants of the Ekeland variational principle involving the Clarke normal cone and establish sufficient conditions for a set-valued map to have a weak minimizer or a properly positive minimizer when it satisfies Palais-Smale type conditions. 相似文献
422.
In this paper we study set-valued optimization problems with equilibrium constraints (SOPECs) described by parametric generalized
equations in the form 0 ∈ G(x) + Q(x), where both G and Q are set-valued mappings between infinite-dimensional spaces. Such models particularly arise from certain optimization-related
problems governed by set-valued variational inequalities and first-order optimality conditions in nondifferentiable programming.
We establish general results on the existence of optimal solutions under appropriate assumptions of the Palais-Smale type
and then derive necessary conditions for optimality in the models under consideration by using advanced tools of variational
analysis and generalized differentiation.
Dedicated to Jiří V. Outrata on the occasion of his 60th birthday.
This research was partly supported by the National Science Foundation under grants DMS-0304989 and DMS-0603846 and by the
Australian Research Council under grant DP-0451168. 相似文献
423.
TiO2 Nanotubes: Nitrogen‐Ion Implantation at Low Dose Provides Noble‐Metal‐Free Photocatalytic H2‐Evolution Activity 下载免费PDF全文
Xuemei Zhou Dr. Volker Häublein Dr. Ning Liu Nhat Truong Nguyen Eva M. Zolnhofer Dr. Hiroaki Tsuchiya Dr. Manuela S. Killian Prof. Dr. Karsten Meyer Prof. Dr. Lothar Frey Prof. Dr. Patrik Schmuki 《Angewandte Chemie (International ed. in English)》2016,55(11):3763-3767
Low‐dose nitrogen implantation induces an ion and damage profile in TiO2 nanotubes that leads to “co‐catalytic” activity for photocatalytic H2‐evolution (without the use of any noble metal). Ion implantation with adequate parameters creates this active zone limited to the top part of the tubes. The coupling of this top layer and the underlying non‐implanted part of the nanotubes additionally contributes to an efficient carrier separation and thus to a significantly enhanced H2 generation. 相似文献
424.
Truong T.N. Lien Yuzuru Takamura Eiichi Tamiya Mun'delanji C. Vestergaard 《Analytica chimica acta》2015
Alzheimer's disease (AD) is a fatal neurodegenerative disease affecting approximately 26 million people world-wide, and the number is increasing as life expectancy increases. Since the only reliable diagnosis for the pathology is histochemical post-mortem examination, there is a rather urgent need for reliable, sensitive and quick detection techniques. Amyloid beta, being one of the established and widely accepted biomarkers of AD is a target biomolecule. 相似文献
425.
Truong Minh Tuyen 《Journal of Fixed Point Theory and Applications》2017,19(3):1695-1710
The purpose of this paper is to introduce two parallel iterative methods which are based on the hybrid projection and shrinking projection methods to find a common fixed point of a finite family of Bregman strongly nonexpansive operators in a reflexive Banach space X. And we also give some applications of main results for some related problems. 相似文献
426.
427.
D.Q. Pham S. Gangadoo Z. Lu C.C. Berndt E.T. Newsom H. Zreiqat V.K. Truong A.S.M. Ang 《Materials Today Chemistry》2022
A strontium-doped hardystonite (Sr-HT) bioceramic, in bulk form, demonstrates excellent bioactivity for bone regeneration with high fracture toughness and compressive strength. This work examines the antibacterial and mechanical properties of Sr-HT coatings on an alpha-beta titanium alloy with a high specific strength and excellent corrosion resistance (Ti-6Al-4V) produced by atmospheric plasma spray (APS) as the deposition coating technique. A hydroxyapatite (HAp) APS coating, a commercial bioceramic coating, is chosen as the control. The in-situ observation showed that Sr-HT powders experience temperatures during plasma processing that exceeded their melting point to form a coating well adhered to the substrate. It was demonstrated that the Sr-HT coating possessed superior antibacterial properties against Gram-positive methicillin-resistant Staphylococcus aureus (MRSA) and Gram-negative Pseudomonas aeruginosa. In addition, the Sr-HT coating exhibits a uniform distribution of hardness and elastic moduli, higher nanohardness and elastic moduli compared to the equivalent properties of the HAp coating. Moreover, the Sr-HT coating outperforms the HAp coating regarding scratch and wear resistance. The bonding and shear strength of the Sr-HT coating are higher than the values required for orthopedic implant coatings. The Sr-HT coating also allows efficient zinc, silicon and strontium ions release when immersed in cell culture media. In summary, the antibacterial capabilities and the mechanical properties of the Sr-HT APS coating exceed those of the commercial HAp APS coating. Therefore, Sr-HT APS coatings are candidates for bioceramic coating applications in orthopedic implants. 相似文献
428.
Dr. Vinh X. Truong Dr. Katharina Ehrmann Maximilian Seifermann Prof. Dr. Pavel A. Levkin Prof. Dr. Christopher Barner-Kowollik 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(25):e202104466
The ability of light to remotely control the properties of soft matter materials in a dynamic fashion has fascinated material scientists and photochemists for decades. However, only recently has our ability to map photochemical reactivity in a finely wavelength resolved fashion allowed for different colors of light to independently control the material properties of polymer networks with high precision, driven by monochromatic irradiation enabling orthogonal reaction control. The current concept article highlights the progress in visible light-induced photochemistry and explores how it has enabled the design of polymer networks with dynamically adjustable properties. We will explore current applications ranging from dynamic hydrogel design to the light-driven adaptation of 3D printed structures on the macro- and micro-scale. While the alternation of mechanical properties via remote control is largely reality for soft matter materials, we herein propose the next frontiers for adaptive properties, including remote switching between conductive and non-conductive properties, hydrophobic and hydrophilic surfaces, fluorescent or non-fluorescent, and cell adhesive vs. cell repellent properties. 相似文献
429.
K.?Derek?Berglund My?T.?Truong Todd?M.?Przybycien Robert?D.?Tilton Lynn?M.?WalkerEmail author 《Rheologica Acta》2004,43(1):50-61
Rheology and adsorption studies are performed on a model multicomponent system of hydrophobically modified cellulose (hmHEC), anionic surfactant (SDS), and negatively charged silica. Optical reflectometry measurements on silica quantify the total adsorbed mass from polymer-surfactant mixtures and indicate that the adsorption is irreversible. Linear and nonlinear rheological measurements show that the addition of colloidal silica to polymer-surfactant mixtures leads to complex and unexpected changes in behavior that cannot be explained simply as depletion of the bulk solution via adsorption to the colloidal surface. Instead, the combination of rheology and adsorption measurements indicates that the colloidal silica becomes an integral part of the transient network shifting the dynamics of the system. 相似文献
430.