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1.
Inorg Chem ; 63(1): 462-473, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38141022

RESUMO

Adding hydrophilic ligands into aqueous solutions for the selective binding of actinides(III) is acknowledged as an advanced strategy in Ln(III)/An(III) separation. In view of the recycling and radioactive waste disposal of the minor actinide, there remains an urgent need to design and develop the appropriate ligand for selective separation of An(III) from Ln(III). Herein, four novel hydrophilic ligands with hard-soft hybrid donors, derived from the pyridine and phenanthroline skeletons, were designed and synthesized as masking agents for selective complexation of An(III) in the aqueous phase. The known N,N,N',N'-tetraoctyl diglycolamide (TODGA) was used as lipophilic extractant in the organic phase for extraction of Ln(III), and a new strategy for the competitive extraction of An(III) and Ln(III) was developed based on TODGA and the above hydrophilic ligands. The optimal hydrophilic ligand of N,N'-bis(2-hydroxyethyl)-2,9-dicarboxamide-1,10-phenanthroline (2OH-DAPhen) displayed exceptional selectivity toward Am(III) over Ln(III), with the concentrations of HNO3 ranging from 0.05 to 3.0 M. The maximum separation factors were up to 1365 for Eu/Am, 417.66 for Eu/Cm, and 42.38 for La/Am. The coordination mode and bonding property of 2OH-DAPhen with Ln(III) were investigated by 1H NMR titration, UV-vis spectrophotometric titration, luminescence titration, FT-IR, ESI-HRMS analysis, and DFT calculations. The results revealed that the predominant species formed in the aqueous phase was a 1:1 ligand/metal complex. DFT calculations also confirmed that the affinity of 2OH-DAPhen for Am(III) was better than that for Eu(III). The present work using a competitive extraction strategy developed a feasible alternative method for the selective separation of trivalent actinides from lanthanides.

2.
Sci Bull (Beijing) ; 69(4): 473-482, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38123429

RESUMO

The growth of data and Internet of Things challenges traditional hardware, which encounters efficiency and power issues owing to separate functional units for sensors, memory, and computation. In this study, we designed an α-phase indium selenide (α-In2Se3) transistor, which is a two-dimensional ferroelectric semiconductor as the channel material, to create artificial optic-neural and electro-neural synapses, enabling cutting-edge processing-in-sensor (PIS) and computing-in-memory (CIM) functionalities. As an optic-neural synapse for low-level sensory processing, the α-In2Se3 transistor exhibits a high photoresponsivity (2855 A/W) and detectivity (2.91 × 1014 Jones), facilitating efficient feature extraction. For high-level processing tasks as an electro-neural synapse, it offers a fast program/erase speed of 40 ns/50 µs and ultralow energy consumption of 0.37 aJ/spike. An AI vision system using α-In2Se3 transistors has been demonstrated. It achieved an impressive recognition accuracy of 92.63% within 12 epochs owing to the synergistic combination of the PIS and CIM functionalities. This study demonstrates the potential of the α-In2Se3 transistor in future vision hardware, enhancing processing, power efficiency, and AI applications.

3.
Chemosphere ; 337: 139321, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37385483

RESUMO

Amidoxime compounds have been widely used in metal separation and recovery because of their excellent chelating properties to metal ions, especially to uranium (VI). In this study, N, N-bis (2-hydroxyethyl) malonamide was obtained from ethanolamine and dimethyl malonate, and used to prepare a two-dimensional network polymer, then the obtained polymer was immobilized in an environmentally friendly chitosan biomembrane, which enhanced its stability and hydrophobicity, meanwhile the amidoxime functionalization was achieved by oximation reaction of bromoacetonitrile, the application of the material further extends to uranium (VI) separation in solutions. Due to the synergistic action of amide group and amidoxime group, poly (ethanolamine-malonamide) based amidoxime biomembranes (PEA-AOM) showed extraordinary adsorption effect on uranium (VI), among which the saturation adsorption capacity of PEA-AOM-2 was 748.64 mg/g. PEA-AOM-2 also had good reusability (following five cycles of adsorption-desorption, the recovery rate maintained at 88%) and selectivity for uranium (VI), showing satisfactory results in competitive ion coexistence system and simulated seawater experiments. This study demonstrated that PEA-AOM-2 provided a new option for uranium (VI) separation in complex environment and low-concentration uranium background.


Assuntos
Polímeros , Urânio , Urânio/análise , Adsorção
4.
J Chem Inf Model ; 62(6): 1368-1375, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35290042

RESUMO

Fluorescent molecules are important tools in biological detection, and numerous efforts have been made to develop compounds to meet the desired photophysical properties. For example, tuning the wavelength allows an appropriate penetration depth with minimal interference from the autofluorescence/scattering for a better signal-to-noise contrast. However, there are limited guidelines to rationally design or computationally predict the optical properties from first principles, and factors like the solvent effects will make it more complicated. Herein, we established a database (SMFluo1) of 1181 solvated small-molecule fluorophores covering the ultraviolet-visible-near-infrared absorption window and developed new machine learning models based on deep neural networks for accurately predicting photophysical parameters. The optimal system was applied to 120 out-of-sample compounds, and it exhibited remarkable accuracy with a mean relative error of 1.52%. In this new paradigm, a deep learning algorithm is promising to complement conventional theoretical and experimental studies of fluorophores and to greatly accelerate the discovery of new dyes. Due to its simplicity and efficiency, data from newly developed fluorophores can be easily supplemented to this system to further improve the accuracy across various dye families.


Assuntos
Corantes Fluorescentes , Redes Neurais de Computação , Humanos , Aprendizado de Máquina , Solventes
5.
Int J Biol Macromol ; 156: 1234-1242, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31759029

RESUMO

This study focuses on preparing the monoclonal antibody (MAb) against subgroup A of avian leukosis virus (ALV-A) and identifying its antigenic epitope. The ALV-A gp85 gene with a size of 1005bp was amplified and expressed into a recombinant protein with a size of 46KD in E.coli. The products expressed after purification were inoculated into BALB/c mice for preparing antibody-secreting splenic lymphocytes and further obtaining hybridoma cells. Finally, one new hybridoma cell (A18GH) secreting MAb against ALV-A was screened, and the MAb was able to detect ALV-A/K strains in an indirect immunofluorescence assay (IFA), but not ALV-B/J strains. A total of 14 overlapping truncated ALV-A gp85 protein segments were expressed and eight peptides containing different antigenic amino acids were artificially synthesized for analyzing the antigenic epitope of the MAb using a western blot or an ELISA, and the results indicate that the antigenic epitope consists of seven amino acids within the 146-ATRFLLR -152 region of the ALV-A gp85 protein. A biological information analysis shows that the antigenic epitope has a high antigenic index and develops a curved linear spatial structure. Further, its 7 amino acids are completely within the 17 representative ALV-A strains, 4 are within the 11 ALV-K strains, and fewer are within the ALV-B/J/E strains. This study will significantly assist in a further understanding of the protein structure and function of ALV-A, and in the establishment of specific ALV-A detection methods.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos Virais/imunologia , Vírus da Leucose Aviária/imunologia , Mapeamento de Epitopos , Anticorpos Monoclonais/genética , DNA Recombinante/genética , Especificidade da Espécie
6.
Angew Chem Int Ed Engl ; 51(34): 8624-7, 2012 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-22847823

RESUMO

What a ring formation! Bicyclic dihydropyrrolizines with an electron-withdrawing group (EWG) at the 5-position are formed in one step from linear azidoenynes under gold catalysis. This novel route involves the use of azide as a nitrene precursor, electronically-controlled regioselectivity, and the generation of destabilized 1-azapentadienium ions and their pericyclic reactions. This method was used for a formal synthesis of 7-methoxymitosene.


Assuntos
Antibacterianos/síntese química , Ouro/química , Mitomicinas/síntese química , Pirróis/síntese química , Antibacterianos/química , Catálise , Química Farmacêutica , Mitomicinas/química , Estrutura Molecular , Pirróis/química , Estereoisomerismo
7.
Chem Commun (Camb) ; 46(16): 2823-5, 2010 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-20369195

RESUMO

Iron-catalyzed aryl C-H and vinyl C-H bonds activation to give valuable substituted indole products was reported. The reaction shows high functional group tolerance.

8.
J Org Chem ; 75(4): 1305-8, 2010 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-20088585

RESUMO

A domino reaction via palladium-catalyzed Sonogashira coupling of benzimidoyl chlorides with 1,6-enynes and then cyclization to form quinoline derivatives has been developed. The reaction conditions and the scope of the process are examined, and a plausible mechanism is proposed. The procedure is simple, rapid, and general, and the substrates are readily available.


Assuntos
Alcinos/química , Benzamidas/química , Paládio/química , Quinolinas/síntese química , Catálise , Ciclização , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Quinolinas/química , Relação Estrutura-Atividade
9.
Chem Commun (Camb) ; (36): 5451-3, 2009 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-19724815

RESUMO

A novel iodine-catalyzed tandem cyclization-cycloaddition reaction of ortho-alkynyl-substituted benzaldehydes leading to polyoxacyclic ring systems has been developed, which represents a useful approach towards the synthesis of the oxabicyclo-[3.2.1]octane ring skeleton found in a variety of natural products.


Assuntos
Óxidos Heterocíclicos/síntese química , Iodo/química , Compostos Policíclicos/síntese química , Alcinos/química , Benzaldeídos/química , Catálise , Cristalografia por Raios X , Ciclização , Óxidos Heterocíclicos/química , Modelos Químicos , Conformação Molecular , Compostos Policíclicos/química
10.
J Org Chem ; 74(7): 2893-6, 2009 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-19271738

RESUMO

Ag-catalyzed cyclization of 2-alkynyl benzyl azides offers a novel and efficient method for the synthesis of substituted isoquinoline. The reaction proceeds smoothly in moderate to good yields and tolerates considerable functional groups. The reaction conditions and the scope of the process are examined, and a plausible mechanism is proposed.


Assuntos
Azidas/química , Benzeno/química , Isoquinolinas/síntese química , Prata/química , Alquilação , Catálise , Ciclização , Elétrons , Isoquinolinas/química , Estrutura Molecular
11.
J Org Chem ; 72(22): 8600-3, 2007 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-17918899

RESUMO

A facile and efficient synthesis of 1,3-diaryl-5-spirohexahydropyrimidines via a one-pot condensation of anilines, formaldehyde, and cyclohexanones is reported. In this one-pot, three-component reaction, six molecules of reactants are involved and six new covalent bonds are generated. Bicyclic products are obtained from the starting materials in one pot using readily available starting materials and catalysts.


Assuntos
Cicloexanonas/química , Formaldeído/química , Piridinas/química , Pirimidinas/síntese química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular , Pirimidinas/química , Estereoisomerismo
12.
Phytochemistry ; 67(2): 107-21, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16332380

RESUMO

Lathyrus sativus (grass pea) is a high-yielding, drought-resistant legume consumed as a food in Northern India and neighboring countries as well as in Ethiopia. Its development into an important food legume, however, has been hindered by the presence of the neurotoxin - beta-N-oxalyl-L-alpha,beta-diaminopropionic acid (beta-ODAP) in seeds which, if consumed in large quantities for prolonged periods, can cause irreversible paralysis. Recently, some low-toxin lines have been developed that may prove safe for both animal and human foods. Cultivation of L. sativus should thus be considered in suitable regions because the demand for legume animal feed protein products is expected to increase. This paper addresses advances in understanding L. sativus from the perspective of its taxonomy, genetics, ecology, chemistry, nutrition, medicine, biology and for animal nutrition.


Assuntos
Diamino Aminoácidos , Lathyrus , Neurotoxinas , Diamino Aminoácidos/química , Diamino Aminoácidos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Humanos , Lathyrus/química , Lathyrus/genética , Lathyrus/metabolismo , Neurotoxinas/química , Neurotoxinas/metabolismo , Valor Nutritivo , Sementes/química
13.
J Org Chem ; 70(20): 8204-7, 2005 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-16277350

RESUMO

[Chemical reaction: see text] Polysubstituted furans and highly functionalized 2H-pyrans were prepared in good yields by DABCO-catalyzed reactions of alpha-halo carbonyl compounds with dimethyl acetylenedicarboxylate (DMAD) at room temperature.


Assuntos
Ácidos Dicarboxílicos/química , Furanos/síntese química , Piperazinas , Piranos/síntese química , Catálise , Furanos/química , Óxidos/química , Piranos/química
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