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131.
Georgios P. Trachanas Nikolaos B. Zographopoulos 《Journal of Differential Equations》2018,264(4):3070-3071
There is an corrigendum in the paper “Orbital stability for the Schrödinger operator involving inverse square potential”, Journal of Differential Equations 259 (2015) 4989–5016. 相似文献
132.
Nikolaos V. Tzouras Dr. Fady Nahra Dr. Laura Falivene Prof. Dr. Luigi Cavallo Marina Saab Prof. Dr. Kristof Van Hecke Dr. Alba Collado Dr. Christopher J. Collett Prof. Dr. Andrew D. Smith Prof. Dr. Catherine S. J. Cazin Prof. Dr. Steven P. Nolan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(20):4515-4519
We have been puzzled by the involvement of weak organic and inorganic bases in the synthesis of metal–N-heterocyclic carbene (NHC) complexes. Such bases are insufficiently strong to permit the presumed required deprotonation of the azolium salt (the carbene precursor) prior to metal binding. Experimental and computational studies provide support for a base-assisted concerted process that does not require free NHC formation. The synthetic protocol was found applicable to a number of transition-metal- and main-group-centered NHC compounds and could become the synthetic route of choice to form M–NHC bonds. 相似文献
133.
Glen R. Jones Dr. Athina Anastasaki Richard Whitfield Nikolaos Engelis Evelina Liarou Prof. David M. Haddleton 《Angewandte Chemie (International ed. in English)》2018,57(33):10468-10482
Key advances within the past 10 years have transformed copper‐mediated radical polymerization from a technique which was not very tolerant of protic media into a range of closely related processes capable of controlling the polymerization of a wide range of monomers in pure water at ppm catalyst loadings. This approach has afforded water‐soluble macromolecules of desired molecular weight, architecture, and chemical functionality, with applications ranging from drug delivery to oil processing. In this Review we highlight and critically evaluate the synthetic methods that have been developed to control radical polymerization in water by using copper complexes as well as identify future areas of interest and challenges still to be overcome. 相似文献
134.
Plant molecular pharming is a technology that uses plants as bioreactors to produce recombinant molecules of medical and veterinary importance. In the present study, we evaluated the ability of histamine (HIM), tryptamine (TRM), phenylamine (PHEM) and tyramine (TYRM) coupled to Sepharose CL-4B via a 1,4-butanediol diglycidyl ether spacer to bind and purify human monoclonal anti-HIV antibody 2F5 (mAb 2F5) from spiked maize seed and tobacco leaf extracts. Detailed studies were carried out to determine the factors that affect the chromatographic behaviour of mAb 2F5 and also maize seed and tobacco leaf proteins. All affinity adsorbents showed a reduced capacity to bind and a reduced ability to purify proteins from tobacco extract compared to maize extract. Under optimal conditions, HIM exhibited high selectivity for mAb 2F5 and allowed a high degree of purification (>95% purity) and recovery (>90%) in a single step with salt elution (0.4 M KCl) from spiked maize seed extract. Analysis of the purified antibody fraction by ELISA and Western blot showed that the antibody was fully active and free of degraded variants or modified forms. The efficacy of the system was assessed further using a second therapeutic antibody (human monoclonal anti-HIV antibody mAb 2G12) and a therapeutic enzyme (alpha-chymotrypsin). HIM may find application in the purification of a wide range of biopharmaceuticals from transgenic plants. 相似文献
135.
Nikolaos S. Papageorgiou Eugénio M. Rocha Vasile Staicu 《Calculus of Variations and Partial Differential Equations》2008,33(2):199-230
In this paper we study second order elliptic equations driven by the Laplacian and p-Laplacian differential operators and
a nonlinearity which is (p-)superlinear (it satisfies the Ambrosetti–Rabinowitz condition). For the p-Laplacian equations
we prove the existence of five nontrivial smooth solutions, namely two positive, two negative and a nodal solution. Finally
we indicate how in the semilinear case, Morse theory can be used to produce six nontrivial solutions.
This paper was completed while the first author was visiting the University of Aveiro as an Invited Scientist. The hospitality
and financial support of the host institution are gratefully acknowledged. The second and third authors acknowledge the partial
financial support of the Portuguese Foundation for Science and Technology (FCT) under the research project POCI/MAT/55524/2004. 相似文献
136.
James Colliander Justin Holmer Nikolaos Tzirakis 《Transactions of the American Mathematical Society》2008,360(9):4619-4638
We prove low regularity global well-posedness for the 1d Zakharov system and the 3d Klein-Gordon-Schrödinger system, which are systems in two variables and . The Zakharov system is known to be locally well-posed in and the Klein-Gordon-Schrödinger system is known to be locally well-posed in . Here, we show that the Zakharov and Klein-Gordon-Schrödinger systems are globally well-posed in these spaces, respectively, by using an available conservation law for the norm of and controlling the growth of via the estimates in the local theory.
137.
Mukesh Agrawal Andrij Pich Nikolaos E. Zafeiropoulos Manfred Stamm 《Colloid and polymer science》2008,286(5):593-601
Submicron hollow spheres are an interesting class of materials that receive significant attention nowadays. Closed and mechanically
robust homogeneous hollow titania microspheres with as much shell thickness as 130 nm were fabricated by coating polystyrene
beads with titania nanoparticles using sol–gel chemistry and subsequently removing the core either via heating or a chemical
dissolution process. The thickness of the titania shell deposited on polystyrene core was finely tuned between 100 and 130 nm
by varying the concentration of titania precursor, i.e., Ti(OEt)4 salt from 0.5 to 2 mM during the coating process. The obtained hybrid core–shell particles and hollow microspheres were characterized
by scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, X-ray diffraction, and thermo-gravimetric
analysis. The approach employed is well suited to the preparation of titania-coated polystyrene hybrid particles and hollow
titania spheres, which can find their applications as novel building blocks with unique optical properties for fabrication
of advanced materials, catalyst, and drug delivery system. 相似文献
138.
George Asimellis Nikolaos Michos Ioanna Fasaki Michael Kompitsas 《Spectrochimica Acta Part B: Atomic Spectroscopy》2008
Development and application of an in-situ applicable method to provide rapid determination of platinum group metals (platinum, palladium, and rhodium) elemental concentration in automobile catalyst scrap is reported. Application is based on laser-induced breakdown spectroscopy (LIBS). Actual automobile catalyst slurry in powder form was used to develop the application. With a method requiring approximately 1.5 min of examination per sample, calibration curves are presented with linear regression coefficients close to 0.99 and stability better than 3.0%. 相似文献
139.
Agrawal M Pich A Gupta S Zafeiropoulos NE Simon P Stamm M 《Langmuir : the ACS journal of surfaces and colloids》2008,24(3):1013-1018
Sub-micrometer-sized hollow tantalum oxide (Ta2O5) spheres with tunable shell thickness and void size have been fabricated exploiting beta-diketone-functionalized polystyrene (PS) beads as sacrificial templates in a sol-gel process. First, a controlled precipitation of Ta2O5 nanoparticles was carried out on the template surface by hydrolyzing tantalum ethoxide (Ta(OEt)5) at room temperature, and subsequently, the polymer core was removed either via chemical treatment with toluene or calcination at 650 degrees C. The thickness of the tantala shell precipitated on the PS core during the coating process was tuned between 100 and 142 nm by varying the concentration of tantala precursor in the reaction media. The obtained Ta2O5-coated PS particles and hollow microspheres were characterized by scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, X-ray diffraction, and thermogravimetric analysis. Due to the unique optical and dielectric properties, these nanostructured materials are envisaged to be used in applications such as novel building blocks for the fabrication of advanced materials, surface coatings, catalysts, and drug delivery systems. 相似文献
140.
Tsikouris O Bartl T Tousek J Lougiakis N Tite T Marakos P Pouli N Mikros E Marek R 《Magnetic resonance in chemistry : MRC》2008,46(7):643-649
Substituted pyrazolopyridines are potent inhibitors of phosphodiesterases and cyclin-dependent kinases. In this study, NMR was used to investigate the potential N1-H and N2-H tautomerism of 5-substituted pyrazolo[3,4-c]pyridine derivatives. Six compounds were fully characterized by using (1)H, (13)C, and (15)N chemical shifts and indirect (1)H--(13)C and (1)H--(15)N coupling constants. The (1)H NMR spectra were measured over a broad range of temperatures. All of the compounds were shown to exist predominantly in the N1-H tautomeric form. Complementary quantum-chemical calculations of the chemical shieldings and indirect spin-spin couplings support the structural conclusions drawn. 相似文献