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931.
932.
Meng Zhiqing Jiang Min Shen Rui Xu Leiyan Dang Chuangyin 《Journal of Global Optimization》2021,81(3):599-620
Journal of Global Optimization - Biconvex programming is nonconvex optimization describing many practical problems. The existing research shows that the difficulty in solving biconvex programming... 相似文献
933.
Tran Duc Thiep Truong Thi An Phan Viet Cuong Nguyen The Vinh 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):89-96
We have determined the isomeric ratios in 130Ba(γ, n)129m,gBa, 132Ba(γ, n)131m,gBa and 134Ba(γ, n)133m,gBa photonuclear reactions of natural barium induced by bremsstrahlungs with end-point energies in the giant dipole resonance
region. The investigated samples were irradiated at electron accelerator Microtron MT-25 of the Flerov Laboratory of Nuclear
Reaction, Joint Institute for Nuclear Research, Dubna, Russia. The gamma spectra of the samples irradiated were measured with
spectroscopic system consisting of 8192 channel analyzer and high-energy resolution (180 keV at gamma ray 1332 keV of 60Co) HP(Ge) semiconductor detector Canberra. The GENIE2000 (Canberra) computer program was used for data processing. The results
were discussed and compared with those of other authors. 相似文献
934.
Vu T. Nguyen Viet D. Nguyen Graham C. Haug Ngan T. H. Vuong Hang T. Dang Dr. Hadi D. Arman Dr. Oleg V. Larionov 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(20):7995-8001
The development of efficient and selective C−N bond-forming reactions from abundant feedstock chemicals remains a central theme in organic chemistry owing to the key roles of amines in synthesis, drug discovery, and materials science. Herein, we present a dual catalytic system for the N-alkylation of diverse aromatic carbocyclic and heterocyclic amines directly with carboxylic acids, by-passing their preactivation as redox-active esters. The reaction, which is enabled by visible-light-driven, acridine-catalyzed decarboxylation, provides access to N-alkylated secondary and tertiary anilines and N-heterocycles. Additional examples, including double alkylation, the installation of metabolically robust deuterated methyl groups, and tandem ring formation, further demonstrate the potential of the direct decarboxylative alkylation (DDA) reaction. 相似文献
935.
In this paper, we introduce a localized version of generalized normal maps as well as generalized natural mappings. By using
these concepts, we study continuity properties of the solution map of parametric variational inequalities in reflexive Banach
spaces. This localization permits us to deal with variational conditions posed on sets that may not be convex and to establish
existence and continuity of solutions. We also establish homeomorhisms between the solution set of variational inequalities
and the solution set of generalized normal maps. Using these homeomorphisms and the degree theory, we show that the solution
map of parametric variational inequalities is lower semicontinuous. Our results extend some results of Robinson (Set-Valued
Anal 12:259–274, 2004).
The authors wish to express their sincere appreciation to Professor Stephen M. Robinson, Department of Industrial and Systems
Engineering, University of Wisconsin-Madison, for his valuable comments and suggestions. This research was partially supported
by a grant from National Science Council of Taiwan, ROC. 相似文献
936.
Thuy Trang NguyenThanh Cong Bach Huong Thao PhamThe Tan Pham Duc Tho NguyenNam Nhat Hoang 《Physica B: Condensed Matter》2011,406(19):3613-3621
The electronic structures of bulk, 2D slabs and clusters of CaMnO3 in various magnetic configurations are presented. The obtained results including optimized cell constant, band-gap, Mn magnetic moment, on-site Coulomb repulsion potential and p-d charge separation potential are in good agreement with experiment data. The energetically most preferable configuration was an insulating charge-transfer ground state with G-type antiferromagnetic (AF) configuration (classified according to Wollan and Koehler, Phys. Rev. 100 (1955) 545). For the finite 2D layers the C-type AF ground state was found to be most stable. The surface effect on magnetism of finite quasi 2D systems appeared to originate in the pyramidal field splitting of Mn 3d levels, which induced the formation of ferromagnetic (FM) regions within the AF matrix and the extension of FM correlation deep through 7 subsurface layers (2.7 nm from the surface). All finite systems (clusters and slabs) were found non-conducting due to the localization of electrons and the cancellation of surface excess carriers (holes) after surface relaxation, although the band-gaps of 2D systems were sufficiently reduced in comparison with that of the bulk. 相似文献
937.
938.
A facile method was developed to load a large amount of silver nanoparticles into a biodegradable and biocompatible cellulose acetate (CA) nanofibrillar aerogel in a controlled manner. The micro-sized CA fibrils were separated into nano-sized fibrils by salt-assisted chemical treatment in a water-acetone co-solvent to give a nanofibrillar structure with a diameter of 20-50 nm, BET surface area of 110 m2/g, and porosity of 96%. Using the high electron-rich oxygen density in the CA macromolecules and the large surface area of the CA nanoporous structure as an effective nanoreactor, the in-situ direct metallization technique was successfully used to synthesize Ag nanoparticles with an average diameter of 2.8 nm and a loading content of up to 6.98 wt%, which can hardly be achieved by previous methods. This novel procedure provides a facile and economic way to manufacture Ag nanoparticles supported on a porous membrane for various biomedical applications. 相似文献
939.
Kuo‐Huai Kuo Yu‐Hsiang Peng Wen‐Yen Chiu Trong‐Ming Don 《Journal of polymer science. Part A, Polymer chemistry》2008,46(18):6185-6197
High loading of stable carbon black (CB) dispersion in organic solvent, PGMEA, was prepared by a ball‐milling process when using poly(styrene‐EHA‐HEMA)‐block‐poly(styrene‐EHA‐HEMA‐DMAEMA) (P(SEH)‐b‐P(SEHD)) as a dispersant. The P(SEH)‐b‐P(SEHD) containing P(SEH) as a steric chain and P(SEHD) as an anchoring chain was prepared by TEMPO‐mediated polymerization. The tertiary amine group of DMAEMA in P(SEHD) chain could be adsorbed onto CB by the interaction with the carboxylic acid group on surface of CB and the P(SEH) chain could provide sufficiently steric repulsion force to avoid the aggregation of CB. In addition, a photosensitive dispersant, P(SEH)‐b‐P(SEHD)C?C, containing the methacrylate double bond side group was also synthesized and was used to prepare stable CB dispersion in PGMEA. The effects of the molecular weight between steric and anchoring chains, the content of tertiary amine, and the amount of methacrylate double bond in the dispersant on the particle size of CB were investigated. Furthermore, the influences of various surface properties of CB, such as specific surface area, content of carboxylic acid group, and size of primary particle, on the particle size of CB in dispersion were also discussed. Finally, the photosensitivity of P(SEH)‐b‐P(SEHD)C?C/CB composite was monitored by a photodifferential scanning calorimeter. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6185–6197, 2008 相似文献
940.
Mai Duc Thanh 《Nonlinear Analysis: Theory, Methods & Applications》2010,72(1):231-456
We establish a global existence of traveling waves for diffusive-dispersive conservation laws for locally Lipschitz flux functions. Using Lyapunov stability techniques, we reduce the global problem of finding traveling waves to considering local behaviors of a stable trajectory of the saddle point. 相似文献