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1.
Inorg Chem ; 60(12): 9174-9180, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34081454

RESUMO

Titanium-oxide or polyoxotitanate clusters are a new type of inorganic host materials that can encapsulate inorganic molecules or ions. We report herein a (NH4)4(enH2)[Ti18O27(PhCOO)24(en)9] molecular cage (Ti18) that encapsulates an entire organic ethylenediamine (en) ion. A thorough investigation has revealed the extraordinary versatility of en. Besides being a guest cation, it also functions as chelating and bridging ligand. It balances the charge of the negative Ti18 cage and facilitates the deprotonation of benzoic acid at the early stage of the reaction as well. DFT calculation and a derivative of Ti18 with open sites at its equatorial position shed further light on the formation mechanism. Ti18 strongly absorbs visible light as a result of en coordination, and it exhibits superior photocatalytic activity compared to anatase TiO2.

2.
Nurs Open ; 10(8): 4948-4958, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37247329

RESUMO

AIM: The aim of this study was to summarise the overall picture of thirst-related research in patients with heart failure. DESIGN: We conducted a scoping review following the Arskey and O'Malley methodological framework along with the PAGER framework. METHODS: PubMed, CINAHL, Web of Science, Embase, The Cochrane Library, Jonna Briggs Institute, ProQuest Database, Google Scholar, PsycINFO, PQDT, CNKI, Wan Fang, VIP and CBM. Additionally, grey literature including grey databases (Opengrey, OpenDoar, Openaire and BASEL Bielefeld Academic Search Engine), conferences or articles (Scopus and Microsoft Academic), graduate theses databases (eTHOS, DART Europe, Worldcat and EBSCO Open Dissertations) and government information media (UK guidance and regulations, USA government websites, EU Bookshop and UN official publications) were searched. The databases were searched from inception to 18 August 2022 for Articles written in English and Chinese. Two researchers independently screened articles based on inclusion and exclusion criteria, and a third researcher adjudicated disagreements. RESULTS: We retrieved 825 articles, of which 26 were included. Three themes were summarised from these articles: (a) the incidence of thirst in patients with heart failure; (b) the thirst-related factors in patients with heart failure; and (c) the intervention measures of thirst in patients with heart failure.


Assuntos
Insuficiência Cardíaca , Sede , Humanos , Europa (Continente)
3.
ACS Nano ; 17(12): 11607-11615, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37288740

RESUMO

Photochemical methods are effective for controllable synthesis of silver nanoparticles with specific sizes and shapes. Whether they are capable of fabricating Ag nanoclusters (NCs) with atomic precision is yet to be proved. In this work, we synthesize an atomically precise Ag NC, [Ag25(4-MePhC≡C)20(Dpppe)3](SbF6)3 (Ag25), via a process mediated by visible light. Its total structure is determined by X-ray crystallography. The investigation of the mechanism reveals that the formation of Ag25 is triggered by a photoinduced electron-transfer (PET) process. An electron of certain amines is excited by light with wavelength shorter than 455 nm and transferred to Ag+. The amine is oxidized to the corresponding amine N-oxide. Such a PET process is supported by experimental and density functional theory studies. To expand the application scope of the photochemical method, another three NCs, [Ag19(4-tBuPhC≡C)14(Dpppe)3](SbF6)3 (Ag19), [Ag32(4-tBuPhC≡C)22(Dppp)4](SbF6)3 (Ag32), and bimetallic [Ag22Au3(4-tBuPhC≡C)20(Dpppe)3](SbF6)3 (Ag22Au3), are produced by replacing certain ingredients. Furthermore, since the formation of Ag19 can be regarded as a photochromatic process, a facile amine visual detection method is also presented based on this mechanism.

4.
RSC Adv ; 10(33): 19397-19400, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35515431

RESUMO

A trifluoromethanesulfonate (OTf) and tert-butylacetylene ( t BuC[triple bond, length as m-dash]C-) co-protected silver nanocluster (NC), Ag43( t BuC[triple bond, length as m-dash]C)24(CF3SO3)8 (Ag43), was synthesized and characterized. Single crystal X-ray diffraction analysis revealed its total structure. 43 Ag atoms are arranged into a three-concentric-shell Ag@Ag12@Ag30 structure. Both OTf and t BuC[triple bond, length as m-dash]C- ligands bonded with Ag atoms in a µ3 mode. The application of Ag43 as a catalyst for the reaction of silane with alcohol or H2O indicated that the surface ligands had a profound passivation effect, which significantly influenced the reactivity and selectivity.

5.
Dalton Trans ; 48(44): 16562-16568, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31657403

RESUMO

Recently, metal-ion-doped zeolitic imidazolate frameworks have gained considerable attention for their structure tailorability and potential catalytic applications. Herein, Cu ion-doped ZIF-8 nanocrystals were successfully prepared by the mechanical grinding of Cu(NO3)2, ZnO and 2-methylimidazole (HMeIM) using ethanol as an additive. In contrast to the general view that only Cu(ii) is present in Cu-doped ZIF-8, we found the coexistence of Cu(ii) and Cu(i) in this material, which was supported by XPS and X-ray induced Auger electron spectroscopy (XAES) characterizations. Moreover, ethanol might have acted as a reducer to induce the reduction of Cu(ii) during synthesis. Due to the mixed valency of Cu ions, the Cu ion-doped ZIF-8 nanocrystals showed excellent catalytic performance in the dehydrogenative coupling of silanes with alcohols.

6.
Sci Rep ; 9(1): 19690, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31873102

RESUMO

Ecosystem issues have been severely concerned and studied when the coal resource is one of major energy generators, and green mining innovation techniques involving artificial-restorations have addressed and significantly lessened negative impacts on the ecological environment. The ecosystem of a coal-mined area, however, is able to naturally restore with the processes of natural succession, similar to the human body system that has the immune ability to self-heal a wound over time if the wound does not deeply hurt the health. Here we analyze multiple discipline real data from two mining sites, and evidently show an ability of nature that the coal mining related problems such as geological cracks, damaged aquifers and destroyed soils in Quaternary period can naturally recover around a half-year after the end of mining. Our results temporally and spatially demonstrate that the damaged ecosystem has a capability of unaided nature-remediation from the ground to the subsurface, which is very useful to the countries worldwide with abundant coal reserves and intense energy demands for their development.

7.
Anal Chim Acta ; 1033: 35-48, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30172330

RESUMO

Capillary tubes are widely used in micro-devices because of their tubular structure, high efficiency, small dead volume and good flexibility. In micro-devices, such as miniaturized chromatography and solid phase microextraction, capillary tubes play a crucial role as stationary phases, carriers or adsorbents for complex sample analysis. Many strategies have been proposed to improve their performance and extend their application by surface engineering. One of the most promising strategies is mussel-inspired chemistry, polydopamine surface modification, which has become a powerful tool in capillary fabrication and modification, as it provides a versatile platform for the construction of diverse hybrid materials with specific functionalities. This review focuses on recent advances in the fabrication of polydopamine-coated capillary tubes for microextraction and miniaturized chromatography systems. In the first part, the preparation strategies of polydopamine coatings are discussed in detail. Next, the application of polydopamine as a novel capillary coating are described. Finally, a conclusion and the key issues that exist in this emerging field are given.

8.
J Pharm Biomed Anal ; 140: 190-198, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28363135

RESUMO

In this study, a novel mesoporous silica nanoparticles incorporated chiral hybrid monolithic stationary phase was developed. The stationary phase was firstly prepared by an in situ copolymerization of amino-modified mesoporous silica nanoparticles (NH2-MSN), glycidyl methacrylate (GMA), and ethylene dimethacrylate (EDMA) and then functionalized with pepsin as chiral selector. The incorporated mesoporous silica nanoparticles provided additional interactions sites, and in turn yielded different enantioselectivity thus enhancing the overall separation. The column was successfully employed for enantioseparation of fifteen basic chiral drugs in capillary electrochromatography. Effects of nanoparticles percentage, pepsin concentration, the pH of running buffer and the applied voltage were investigated. All the analytes could be eluted in less than ten minutes and nine of them could achieve baseline separation. Satisfactory repeatabilities with relative standard deviations less than 4.2% were achieved through intraday, interday, column-to-column and batch-to-batch investigations. These results indicated that the simultaneous utilization of the unique properties of mesoporous silica nanoparticles and versatile features of monoliths could be a promising strategy for enantioseparation.


Assuntos
Nanopartículas , Eletrocromatografia Capilar , Enzimas Imobilizadas , Pepsina A , Porosidade , Dióxido de Silício , Estereoisomerismo
9.
J Chromatogr A ; 1456: 249-56, 2016 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-27334417

RESUMO

Novel graphene oxide (GO)-modified affinity capillary monoliths were developed employing human serum albumin (HSA) or pepsin as chiral selector. Three types of amino donors for GO immobilization, including ammonium hydroxide (NH4OH), ethanediamine (EDA) and polyethyleneimine (PEI), were applied to explore the effect of spacer arm on enantioseparation. It was observed that HSA-GO-EDA-based affinity capillary monoliths exhibited better chiral recognition ability in comparison with the other two spacer-based monoliths. Under the optimized conditions, the obtained columns revealed satisfactory repeatability concerning column-to-column, run-to-run and interday repeatability. In addition, the impact of GO concentration on enantiomeric separation was also investigated. HSA-GO-EDA-based affinity capillary monoliths provided higher chiral selectivity for nine pairs of enantiomers compared to the columns without GO. Furthermore, the influence of amino donors and GO on proteolytic activity of pepsin-based immobilized enzymatic reactor (IMER) was discussed. Unfortunately, pepsin-GO-PEI-based affinity capillary monoliths possessed the highest protein digestion capacity, which was different from the effect of amino donors on enantiorecognition. Moreover, GO presented as a favorable choice to improve the enzymatic activity of IMER. These results proved that GO-functionalized affinity capillary monoliths have promising potential for chiral separation and proteolysis.


Assuntos
Eletroforese Capilar , Grafite/química , Proteólise , Enzimas Imobilizadas/química , Humanos , Indicadores e Reagentes , Pepsina A/química , Albumina Sérica/química , Dióxido de Silício , Estereoisomerismo
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