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1.
This paper provides a full characterization for when the expansion of a complete o-minimal theory, one that extends the theory of ordered divisible abelian groups, by a unary predicate that picks out a divisible, dense and codense group has a model companion. This result is motivated by criteria and questions introduced in the recent works [14] and [10] concerning the existence of model companions, as well as preservation results for some neostability properties when passing to the model companion. Examples are included both in which the predicate is an additive subgroup of a real ordered vector space, and where it is a multiplicative subgroup of the nonzero elements of an o-minimal expansion of a real closed field. The paper concludes with a brief discussion of neostability properties and examples that illustrate the lack of preservation (from the base o-minimal theory to the model companion of the expansion we define) for properties such as strong, NIP, and NTP2, though there are also examples for which some or all three of those properties are preserved.  相似文献   
2.
The main result of this paper is a positive answer to the Conjecture 5.1 of [14] by A. Chernikov, I. Kaplan and P. Simon: If M is a PRC field, then Th(M) is NTP2 if and only if M is bounded. In the case of PpC fields, we prove that if M is a bounded PpC field, then Th(M) is NTP2. We also generalize this result to obtain that, if M is a bounded PRC or PpC field with exactly n orders or p-adic valuations respectively, then Th(M) is strong of burden n. This also allows us to explicitly compute the burden of types, and to describe forking.  相似文献   
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In this work, a novel molecularly imprinted polymer (MIP) for use as a solid phase extraction sorbent was developed for the determination of coenzyme Q10 (CoQ10) in liver extract. CoQ10 is an essential cofactor in mitochondrial oxidative phosphorylation and a powerful antioxidant agent found in low concentrations in biological samples. This fact and its high hydrophobicity make the analysis of CoQ10 technically challenging. Accordingly, a MIP was synthesised using coenzyme Q0 as the template, methacrylic acid as the functional monomer, acetonitrile as the porogen, ethylene glycol dimethacrylate as the crosslinker and benzoyl peroxide as the initiator. Various parameters affecting the polymer preparation and extraction efficiency were evaluated. Morphological characterisation of the MIP and its proper comparison with C18 as a sorbent in solid phase extraction were performed. The optimal conditions for the molecularly imprinted solid phase extraction (MISPE) consisted of 400 μL of sample mixed with 30 mg of MIP and 600 μL of water to reach the optimum solution loading. The loading was followed by a washing step consisting of 1 mL of a 1-propanol solution (1-propanol:water, 30:70,v/v) and elution with 1 mL of 1-propanol. After clean-up, the CoQ10 in the samples was analysed by high performance liquid chromatography. The extraction recoveries were higher than 73.7% with good precision (3.6–8.3%). The limits of detection and quantification were 2.4 and 7.5 μg g−1, respectively, and a linear range between 7.5 and 150 μg g−1 of tissue was achieved. The new MISPE procedure provided a successful clean-up for the determination of CoQ10 in a complex matrix.  相似文献   
5.
Let T be a consistent o-minimal theory extending the theory of densely ordered groups and let T be a consistent theory. Then there is a complete theory T? extending T such that T is an open core of T?, but every model of T? interprets a model of T. If T is NIP, T? can be chosen to be NIP as well. From this we deduce the existence of an NIP expansion of the real field that has no distal expansion.  相似文献   
6.
The bisphenol A (BPA) imprinted polymer microspheres were prepared by simple Pickering emulsion polymerization. Compared to traditional bulk polymerization, both high yields of polymer and good control of particle sizes were achieved. The characterization results of scanning electron microscopy and nitrogen adsorption–desorption measurements showed that the obtained molecularly imprinted polymer microsphere (MIPMS) particles possessed regular spherical shape, narrow diameter distribution (30–60 μm), a specific surface area (SBET) of 281.26 m2 g−1 and a total pore volume (Vt) of 0.459 cm3 g−1. Good specific adsorption capacity for BPA was obtained in the sorption experiment and good class selectivity for BPA and its seven structural analogs (bisphenol F, bisphenol B, bisphenol E, bisphenol AF, bisphenol S, bisphenol AP and bisphenol Z) was demonstrated by the chromatographic evaluation experiment. The MIPMS as solid-phase extraction (SPE) packing material was then evaluated for extraction and clean-up of these bisphenols (BPs) from human urine samples. An accurate and sensitive analytical method based on the MIPMS-SPE coupled with HPLC-DAD has been successfully established for simultaneous determination of eight BPs from human urine samples with detection limits of 1.2–2.2 ng mL−1. The recoveries of BPs for urine samples at two spiking levels (100 and 500 ng mL−1 for each BP) were in the range of 81.3–106.7% with RSD values below 8.3%.  相似文献   
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A molecularly imprinted polymer (MIP) based capacitive sensor for antibiotic detection in drinking water and milk has been developed on a gold coated silicon electrode (Au Electrode). The electrode was fabricated by electropolymerizing monomer resorcinol (RN) on Au surface in presence of sulphanilamide (SN) as a template molecule, to get insulated RN polymer antibiotic composite. The insulation of the polymer film was improved by incubation of electrode in 1‐Dodecanethiol solution. Subsequently MIP sensor was obtained by extraction of SN in ethanol and acetic acid solution. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) measurements were performed for characterization of the developed MIP electrode at different steps of fabrication. The surface morphology of MIP electrode was characterized using atomic force microscopy (AFM), X‐ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive x‐ray spectroscopy (EDS). Performance of MIP sensor was evaluated by measuring change in capacitance against varying concentration of SN using EIS. A linear response in the range 1 to 200 μg L?1 SN was recorded for MIP sensor with a detection limit of 0.1 μg L?1. The developed MIP sensor exhibited good selectivity towards SN in water and milk with recoveries in the range 92 % to 105 %. The obtained results suggest the usability of MIP based sensor for SN estimation in water and milk samples.  相似文献   
9.
In NIP theories, generically stable Keisler measures can be characterized in several ways. We analyze these various forms of “generic stability” in arbitrary theories. Among other things, we show that the standard definition of generic stability for types coincides with the notion of a frequency interpretation measure. We also give combinatorial examples of types in NSOP theories that are finitely approximated but not generically stable, as well as ϕ-types in simple theories that are definable and finitely satisfiable in a small model, but not finitely approximated. Our proofs demonstrate interesting connections to classical results from Ramsey theory for finite graphs and hypergraphs.  相似文献   
10.
A variety of molecularly imprinted polymers (MIPs) against clozapine (CLZ) were synthesized and their recognition properties were compared with blank non-imprinted polymers. Methacrylic acid (MAA) was used as a functional monomer and Chloroform or tetrahydrofuran (THF) were applied as polymerization solvents. Chloroform as the solvent and MAA/CLZ ratio of 5 was selected as optimized polymerization condition. In Scatchard analysis of MIP-CLZ interactions, two classes of binding sites were found in MIP—high affinity (KD = 14.5 μM) and low affinity (KD = 322.5 μM) binding sites. The polymer was evaluated as a selective sorbent in molecularly imprinted solid-phase extraction (MISPE) of CLZ from human serum. The MISPE procedure was developed and optimized with a recovery of 88-102%. The intra- and inter-day precision values were less than 1.36% and 2.5%, respectively. The selectivity of MISPE for CLZ was studied in comparison with some drugs. These drugs could be present with CLZ, simultaneously in serum of patients. The data indicated that the imprinted polymer had a good selectivity and affinity for CLZ and could be used for selective extraction and analysis of CLZ in human serum.  相似文献   
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