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1.
Small ; : e2311799, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38545998

RESUMO

Single atom catalysts (SACs) are highly favored in Li-S batteries due to their excellent performance in promoting the conversion of lithium polysulfides (LiPSs) and inhibiting their shuttling. However, the intricate and interrelated microstructures pose a challenge in deciphering the correlation between the chemical environment surrounding the active site and its catalytic activity. Here, a novel SAC featuring a distinctive Mn-N3-Cl moiety anchored on B, N co-doped carbon nanotubes (MnN3Cl@BNC) is synthesized. Subsequently, the selective removal of the Cl ligands while inheriting other microstructures is performed to elucidate the effect of Cl coordination on catalytic activity. The Cl coordination effectively enhances the electron cloud density of the Mn-N3-Cl moiety, reducing the band gap and increasing the adsorption capacity and redox kinetics of LiPSs. As a modified separator for Li-S batteries, MnN3Cl@BNC exhibits high capacities of 1384.1 and 743 mAh g-1 at 0.1 and 3C, with a decay rate of only 0.06% per cycle over 700 cycles at 1 C, which is much better than that of MnN3OH@BNC. This study reveals that Cl coordination positively contributes to improving the catalytic activity of the Mn-N3-Cl moiety, providing a fresh perspective for the design of high-performance SACs.

2.
Inorg Chem ; 61(23): 8685-8693, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35639458

RESUMO

Titanium oxo clusters (TOCs) with accurate molecular structures have potential applications in photocatalysis, such as photocatalytic degradation, hydrogen production, and water oxidation. The hydrolytic stability and light absorption ability of TOCs have important impacts on photocatalysis, where the selection of peripheral organic ligands plays a significant role. In this regard, salicylhydroxamic acid (abbreviated as H3L) attracts our attention, acting as a ligand for its multidentate and dye-functional features, which can increase the hydrolytic stability and broaden light absorption for TOCs. Herein, two TOCs were solvothermally synthesized and structurally characterized using H3L, formulated as [Ti8(µ2-O)2(µ3-O)2(OiPr)12(L)4]·2CH3CN (1) and [Ti16(µ2-O)10(µ3-O)4(PhCOO)14(L)6(HL)2]·4CH3CN·2iPrOH (2). Complex 2 was obtained by adding excessive benzoic acid over the reaction system of 1, resulting in enhanced hydrolytic stability via the replacement of all alkoxy ligands by multidentate ligands for protection. Interestingly, for the first time, the "three-in-one" structural building mode with {Ti6} + {Ti4} + {Ti6} by the common subunits in 2 was observed among all reported TOCs. Moreover, complex 2 can strongly absorb visible light reaching up to 700 nm and exhibit obvious activity for the photodegradation of methyl orange.


Assuntos
Benzoatos , Titânio , Ligantes , Salicilamidas , Titânio/química
3.
BMC Cardiovasc Disord ; 21(1): 32, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441080

RESUMO

BACKGROUND: Del Nido cardioplegia (DNC) has been proven safe and effective in pediatric patients. However, the use of DNC in adult undergoing cardiovascular surgery lacks support with substantial evidence. This study aimed to evaluate the efficacy of DNC as a cardioplegia of prophylaxis to ventricular arrhythmias associated to cardiovascular surgery in adult patients. METHODS: This study recruited nine hundred fifty-four patients who underwent cardiopulmonary bypass surgeries in Nanjing Hospital affiliated to Nanjing Medical University between January 2019 and December 2019. Among 954 patients, 324 patients were treated with DNC (DNC group), and 630 patients were treated with St. Thomas cardioplegia (STH group). The incidence of postoperative arrhythmia as well as other cardiovascular events relavant to the surgery were investigated in both groups. RESULTS: In DNC group, the incidence of postoperative ventricular arrhythmias was lower (12.4% vs. 17.4%, P = 0.040), and the length of ICU stay was shorter (1.97 ± 1.49 vs. 2.26 ± 1.46, P = 0.004). Multivariate logistic regression demonstrated that the use of DNC helped to reduce the incidence of postoperative ventricular arrhythmias (adjusted odds ratio 0.475, 95% CI 0.266-0.825, P = 0.010). The propensity score-based analysis and subgroup analysis indicated that DNC has the same protecting effects towards myocardial in all kinds of cardiopulmonary bypass surgeries. CONCLUSIONS: Del Nido cardioplegia may potentially reduce the incidence of postoperative ventricular arrhythmias, shorten the length of ICU stay and improve the overall outcome of the patients undergoing cardiovascular surgery.


Assuntos
Arritmias Cardíacas/prevenção & controle , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Soluções Cardioplégicas/uso terapêutico , Ponte Cardiopulmonar/efeitos adversos , Eletrólitos/uso terapêutico , Parada Cardíaca Induzida , Lidocaína/uso terapêutico , Sulfato de Magnésio/uso terapêutico , Manitol/uso terapêutico , Cloreto de Potássio/uso terapêutico , Bicarbonato de Sódio/uso terapêutico , Soluções/uso terapêutico , Adulto , Idoso , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/epidemiologia , Bicarbonatos/efeitos adversos , Bicarbonatos/uso terapêutico , Cloreto de Cálcio/efeitos adversos , Cloreto de Cálcio/uso terapêutico , Soluções Cardioplégicas/efeitos adversos , China/epidemiologia , Eletrólitos/efeitos adversos , Feminino , Parada Cardíaca Induzida/efeitos adversos , Humanos , Incidência , Unidades de Terapia Intensiva , Tempo de Internação , Lidocaína/efeitos adversos , Magnésio/efeitos adversos , Magnésio/uso terapêutico , Sulfato de Magnésio/efeitos adversos , Masculino , Manitol/efeitos adversos , Pessoa de Meia-Idade , Cloreto de Potássio/efeitos adversos , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Bicarbonato de Sódio/efeitos adversos , Cloreto de Sódio/efeitos adversos , Cloreto de Sódio/uso terapêutico , Soluções/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
4.
Chem Commun (Camb) ; 58(63): 8846-8849, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35849002

RESUMO

Carbon hollow sphere encapsulated Ni3Se4 (Ni3Se4@CHS) nanocrystals are prepared using the Ni-soc-MOF by pyrolysis and further selenization. Ni3Se4@CHS exhibits a capacitance of 1720 F g-1 at 1 A g-1 and a capacitance retention of 97% after 6000 cycles at 5 A g-1. Moreover, the asymmetric supercapacitor of Ni3Se4@CHS//AC displays a wide potential window of 1.6 V, an energy density of 45.2 W h kg-1 at a power density of 800 W kg-1, and excellent cycling stability (89% capacitance retention) after 5000 cycles. Overall, this work establishes a significant step to synthesize a new carbon-based material with appreciable capacitance and long cycling durability for potential applications in energy storage and beyond.

5.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 10): o2671, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22065810

RESUMO

The full mol-ecule of the title compound, C(18)H(18)N(2)O(4), is generated by the application of an inversion centre. There are strong π-π inter-actions between adjacent mol-ecules with a centroid-centroid distance of 3.298 (2)Å.

6.
Dalton Trans ; 50(8): 2936-2944, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33555279

RESUMO

Dual-absorber photoelectrodes have been proved to have great potential in the photoelectrochemical (PEC) water splitting application due to their broadband absorption and suitable energy-band position, while the surface/interface issues are still not clearly resolved and understood. Here, during the preparation of a silicon/hematite dual-absorber photoanode achieved via synthesizing a Sn-doped hematite film on the silicon nanowire (SiNW) substrate, we separately introduced the conformal overlayer and interlayer of an Al2O3 thin film by atomic layer deposition. With the thickness-optimized interlayer (overlayer) of the Al2O3 thin film, the photocurrent density at 1.23VRHE can be enhanced from 0.85 mA cm-2 to 1.51 mA cm-2 (1.25 mA cm-2), and the on-set potential has a cathodic shift of ∼0.32 V. Although both the overlayer and interlayer modification can substantially improve the PEC performance, the underlying mechanisms are obviously different. The overlayer can only reduce the carrier recombination on the top surface and in the bulk of the hematite film; in contrast, the interlayer not only passivates the SiNW surface and bottom surface of the hematite film, but also the top surface of the photoanode due to Al3+ thermal diffusion from the bottom to the top surface of the hematite film and the resultant Al2O3 formation. This work deepens our understanding for the roles of the surface and interface engineering in the achievement of high-performance PEC systems based on dual or more absorbers.

7.
Sci Total Environ ; 783: 147041, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34088148

RESUMO

Perfluorooctanoic acid (PFOA) is an emerging organic pollutant that has become ubiquitous in waterways and is difficult to be removed from wastewater using traditional treatment methods. In this study, amino-functionalized graphene oxide (AGO) aerogels were prepared as a potential remediation tool for water contaminated by PFOA. The structure of the prepared absorbent material was characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscope, and X-ray diffraction. The use of various adsorption times, temperatures, solution pH, and absorbent amount were investigated to determine optimum conditions for PFOA adsorption. Adsorption kinetics and thermodynamics of the absorbent were analyzed as well. AGO aerogels exhibited a high adsorption capacity of PFOA (1575 mg∙g-1) and high removal efficiency (99.95%) in a solution containing 10 mg PFOA L-1, likely due to the interconnected porous microstructures and amino groups of the AGO aerogels. The adsorption kinetics and isotherm of PFOA were well-fitted using pseudo-second-order and the Freundlich modelling. The adsorption mechanism of PFOA onto AGO aerogels followed spontaneous, exothermic, and physical processes. This study shows the potential of this material to remove PFOA from PFOA-contaminated waters effectively by providing insight into the understanding of the adsorption mechanisms of PFOA onto AGO aerogels.

8.
Front Chem ; 8: 594093, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33425852

RESUMO

An electrochemical sensor for paracetamol is executed by using conductive MOF (NiCu-CAT), which is synthesized by 2, 3, 6, 7, 10, 11-hexahydroxytriphenylene (HHTP) ligand. The utility of this 2D NiCu-CAT is measured by the detection of paracetamol, p-stacking within the MOF layers is essential to achieve high electrical conductivity, redox activity, and catalytic activity. In particular, NiCu-CAT demonstrated detection Limit of determination near 5µM for paracetamol through a wide concentration range (5-190 µM). The NiCu-CAT/GCE exhibits excellent reproducibility, stability, and interference for paracetamol.

9.
Chem Commun (Camb) ; 56(23): 3405-3408, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32091059

RESUMO

We have developed a unique approach for the thermally promoted cycloaddition of cyclohexadienone-tethered allenes to form a versatile cyclobutane-fused oxygen-containing tricyclic framework in an environmentally friendly and atomic economic fashion with high regioselectivity. The reaction encompasses a broad substrate scope and functional group tolerance of cyclohexadienone moieties. Moreover, the cycloaddition was also applicable to the late-stage functionalization of pharmaceutically relevant compounds.

10.
Nanomaterials (Basel) ; 9(7)2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31266249

RESUMO

To evaluate the influence of transition metal substituents on the characteristics of CH3NH3PbI3/TiO2, we investigated the geometrical and electronic properties of transition metal-substituted CH3NH3PbI3/TiO2 by first-principles calculations. The results suggested that the substitution of Ti4+ at the five-fold coordinated (Ti5c) sites by transition metals is energetically favored. The substituted interface has enhanced visible light sensitivity and photoelectrocatalytic activity by reducing the transition energies. The transition metal substitution can effectively tune the band gap of the interface, which significantly improves the photo-reactivity. The substituted systems are expected to be more efficient in separating the photo-generated electrons-holes and active in the visible spectrum.

11.
Mater Sci Eng C Mater Biol Appl ; 89: 160-165, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29752085

RESUMO

A novel amphiphilic block polymer poly(ethylene glycol)-poly(propylene carbonate)-poly(ethylene glycol) (PEG-PPC-PEG) was synthesized via the dicyclohexylcarbodiimide condensation reaction of double PEG-bis-amine and HOOC-PPC-COOH. The obtained copolymer was characterized by NMR to determine its structure. Using the PEG-PPC-PEG as the carrier and using doxorubicin (DOX) as a model drug, DOX-loaded nanoparticles with core shell structure were synthesized by self-assembly in water. The nanoparticles properties such as particle size, drug loading, encapsulation efficiency (EE) and drug release behavior were investigated as a function of the hydrophobic block length of PPC segments and compared with each other. The results showed that the EE was up to 88.8%. Nanoparticles were found to have a certain effect on the controlled release of DOX.


Assuntos
Portadores de Fármacos/química , Polímeros/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/metabolismo , Liberação Controlada de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Micelas , Nanopartículas/química , Polietilenoglicóis/química , Polietilenos/química , Polímeros/síntese química
12.
Dalton Trans ; 47(30): 10124-10129, 2018 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-30003204

RESUMO

Four unprecedented decanuclear heterometallic [Ln2CoII4CoIII4] clusters based on a diethanolamine ligand (H2dea), namely [Eu2CoII4CoIII4(dea)8(HCOO)4(OH)2(Cl)2(CH3OH)2]Cl2·4CH3OH·2H2O (1), [Gd2CoII4CoIII4(dea)8(HCOO)4(OH)2(Cl)2(CH3OH)2]Cl2·4CH3OH·2H2O (2), [Tb2CoII4CoIII4(dea)8(HCOO)4(OH)2(Cl)2(CH3OH)2]Cl2·2CH3OH·4H2O (3) and [Dy2CoII4CoIII4(dea)8(HCOO)4(OH)2(Cl)2(CH3OH)2]Cl2·2CH3OH·4H2O (4) were synthesized through a facile solution method. Single-crystal X-ray diffraction analyses reveal that complexes 1-4 consist of a [Ln2CoII4CoIII4] core, which is constructed by bridging a quasi-double cuboidal [Ln2CoII2CoIII2] core with two [CoIICoIII] units. Electrospray ionization mass spectrometry (ESI-MS) using methanol solution reveals that complexes 1-4 are stable in the solution, and the clusters undergo three different substitution reactions (Cl- replaced by OH-, OH- replaced by CH3O- and HCOO- replaced by OH-/CH3O-) at the same time in the ionization state. Magnetic susceptibilities reveal ferromagnetic couplings within complexes 3 and 4, and the magnetocaloric effect (MCE) for 2 was also evaluated and the maximum entropy change (-ΔSm) value reaches 16.3 J kg-1 K-1 at about 3 K and 5 T.

13.
J Cardiothorac Surg ; 10: 70, 2015 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-25962897

RESUMO

OBJECTIVE: Observe the efficacy of surgical treatment in patients with severe pulmonary arterial hypertension caused by mitral valve disease. METHODS: We examined the results of surgical treatment in 32 patients with mitral valve disease and severe pulmonary arterial hypertension (pulmonary arterial systolic pressure ≥ 80 mmHg) retrospectively. Operative and postoperative data collection included type of the surgery, cardiopulmonary bypass time, cross-clamp time and the mortality rate. Pulmonary arterial systolic pressure, left atrial diameter, left ventricular end-diastolic diameter, and left ventricular ejection fraction were recorded and compared. RESULTS: A total number of 32 patients had the operation of mitral valve replacement. Among those subjects, twenty-seven patients were surgically replaced with mechanical prosthesis and five patients with tissue prosthesis. Only one patient died of pneumonia, with a mortality rate of 3.1 %. The statistical results of preoperative and postoperative echocardiographic data showed significant decrease in pulmonary arterial systolic pressure (101.2 ± 20.3 versus 48.1 ± 14.3 mmHg, P < 0.05), left atrial diameter(67.6 ± 15.7 versus 54.4 ± 11.4 mm, P < 0.05) and left ventricular end-diastolic diameter (52.3 ± 9.5 versus 49.2 ± 5.9 mm, P < 0.05). There was no significant change in left ventricular ejection fraction (59.2 ± 6.5 versus 57.9 ± 7.6, P = NS). At the time of follow-up, twenty-eight (96.6 %) patients were classified in New York Heart Association functional class I or II, one(3.4 %) in class III, with the mortality rate is zero percent. CONCLUSIONS: Mitral valve replacement can be performed successfully in patients with mitral valve disease and severe pulmonary arterial hypertension with an acceptable perioperative risk.


Assuntos
Implante de Prótese de Valva Cardíaca/métodos , Hipertensão Pulmonar/etiologia , Insuficiência da Valva Mitral/cirurgia , Adulto , Idoso , Ecocardiografia , Feminino , Humanos , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/cirurgia , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/diagnóstico por imagem , Estudos Prospectivos , Índice de Gravidade de Doença , Resultado do Tratamento , Função Ventricular Esquerda
14.
Artigo em Zh | WPRIM | ID: wpr-751207

RESUMO

@#Objective     To investigate the early diagnostic value of urinary neutrophil gelatinase-associated lipocalin (NGAL) for acute kidney injury (AKI) after acute Stanford type A aortic dissection. Methods     From January 2018 to December 2018, the clinical data of 50 patients who underwent open surgery for acute Stanford type A aortic dissection were analyzed in Nanjing First Hospital. Urine specimens were collected before and 2 hours after the aortic dissection surgery. Patients were divided into an AKI group (n=27) and a non-AKI group (n=23) according to the Kidney Disease Improving Global Outcomes criteria. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of urine NGAL.  Results    The incidence of postoperative AKI was 54.00% (27/50). There was a statistically significant difference between the two groups in serum creatinine concentration at 2 hours after surgery and urinary NGAL concentration before the surgery (P<0.05). The area under ROC curve of preoperative urinary NGAL concentration was 0.626. When cut-off value was 43 ng/mL, the sensitivity was 40.7%, specificity was 95.7%. The area under ROC curve of urinary NGAL concentration at 2 hours after surgery was 0.655, and when the cut-off value was 46.95 ng/mL, the sensitivity was 63.0%, specificity was 78.3%.  Conclusion     Urine NGAL can predict postoperative AKI in patients with acute Stanford type A aortic dissection, but its value is limited.

15.
Colloid Polym Sci ; 291: 2181-2189, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23956484

RESUMO

A series of CoIII carboxylate based upon N,N,O,O-tetradentate Schiff base ligand framework have been prepared. X-ray diffraction analysis confirms that these Schiff base CoIII carboxylate are all monomeric species with a six-coordinated central Co in their solid structures. The activities and polycarbonate selectivity of these complexes toward the copolymerization of epoxide (cyclohexene oxide and propylene oxide) and carbon dioxide have been investigated in the presence of bis(triphenylphosphine)iminium chloride. Copolymerization experiments indicate that [bis(α-methyl-3,5-di-tertbutyl-salicylaldehyde) ethylenediiminato] CoIIIOOCH3 exhibits the highest activity and polycarbonate selectivity among these CoIII carboxylate. The resultant copolymer contained almost 100 % carbonate linkages with the molecular weight up to 71.8 kg mol-1 as well as narrow polymer dispersity index (polymer dispersity index = 1.5). The substituents and the mode of the bridging part between the two nitrogen atoms both exert significant influences upon the progress of the copolymerizations, influencing both the polycarbonate selectivity and the rate of copolymerization.

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