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1.
J Am Chem Soc ; 143(13): 5150-5157, 2021 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-33769799

RESUMEN

Ground-level ozone (O3) is one of the main airborne pollutants detrimental to human health and ecosystems. However, the designed synthesis of high-performance O3 elimination catalysts suitable for broadly variable air compositions, especially a variable water vapor content, remains daunting. Herein, we report a new manganese-based metal organic framework, [Mn3(µ3-OH)2(TTPE)(H2O)4]·2H2O (H4TTPE = 1,1,2,2-tetrakis(4-(2H-tetrazol-5-yl)phenyl) ethane), denoted as ZZU-281. ZZU-281 catalyzes O3 decomposition with a nearly constant 100% working efficiency over the entire humidity range from dry (≤5% relative humidity (RH)) to high humidity (90% RH). We found that the maintainable coordinated water molecules and OH groups are activated by Mn2+, becoming active sites for O3 transfer to O2 with a low activation energy. The unique open channels, water retainability, and water stability of ZZU-281 further support the high catalytic performance. This work opens a new avenue for designing efficient catalysts for O3 elimination in practice.

2.
Chem Commun (Camb) ; 58(85): 11985-11988, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36217883

RESUMEN

A pair of 2D chiral frameworks, R-Ag5-1 and S-Ag5-1, with orange fluorescence were successfully synthesized. They were transformed to a thermodynamically favored denser stacking, R-Ag5-3 and S-Ag5-3, accompanied by a change in the luminescence and activating the CPL signal. The capture and structural determination of the intermediates (R-Ag5-2 and S-Ag5-2) reveal that the coordination instability of Na+ ions is the main cause of this transition.


Asunto(s)
Luminiscencia , Plata , Plata/química , Iones/química
3.
Taiwan J Obstet Gynecol ; 60(3): 498-502, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33966735

RESUMEN

OBJECTIVE: The purpose of this study was to analyze the clinical efficacy of five therapeutic strategies in patients with CSP. MATERIALS AND METHODS: A total of 135 CSP patients were included and divided into five groups based on the treatment they received, including transvaginal resection (Group A), laparoscopic resection (Group B), uterine arterial embolization (UAE) combined with hysteroscopic curettage (Group C), UAE combined with uterine curettage (Group D), and hysteroscopic curettage (Group E). To investigate the clinical efficacy of these strategies, intraoperative bleeding, serum ß-hCG levels and recovery time, menstruation recovery time, hormone levels at 1 month after treatment. RESULTS: Patients in group A had the lowest postoperative serum ß-hCG levels, and the shortest recovery times of both serum ß-hCG and menstruation, followed by patients in group B. Group C and D had small amount of blood loss. The hospital stays and costs were low in group E. In addition, the sex hormone levels showed no significant difference among the five groups. CONCLUSION: Our results indicated that resection surgery and UAE have good curative effects, but high hospital costs in CSP treatment. The selection of an optimal treatment regimen for CSP should be carried out based on specific conditions of the patients.


Asunto(s)
Aborto Inducido/métodos , Cesárea/efectos adversos , Cicatriz/complicaciones , Complicaciones Posoperatorias/terapia , Embarazo Abdominal/terapia , Adulto , Gonadotropina Coriónica Humana de Subunidad beta/sangre , Terapia Combinada , Dilatación y Legrado Uterino/métodos , Femenino , Humanos , Histeroscopía/métodos , Laparoscopía/métodos , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/etiología , Embarazo , Embarazo Abdominal/sangre , Embarazo Abdominal/etiología , Resultado del Tratamiento , Embolización de la Arteria Uterina/métodos
4.
Adv Mater ; 33(33): e2101568, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34240480

RESUMEN

The precise identification of single-atom catalysts (SACs) activity and boosting their efficiency toward CO2 conversion is imperative yet quite challenging. Herein, for the first time a series of porous organic polymers is designed and prepared simultaneously, containing well-defined M-N4 and M-N2 O2 single-atom sites. Such a strategy not only offers multiactive sites to promote the catalytic efficiency but also provides a more direct chance to identify the metal center activity. The CO2 photoreduction results indicate that the introduction of salphen unit with Ni-N2 O2 catalytic centers into pristine phthalocyanine-based Ni-N4 framework achieves remarkable CO generation ability (7.77 mmol g-1 ) with a high selectivity of 96% over H2 . In combination with control experiments, as well as theoretical studies, the Ni-N2 O2 moiety is evidenced as a more active site for CO2 RR compared with the traditional Ni-N4 moiety, which can be ascribed to the M-N2 O2 active sites effectively reducing the energy barrier, facilitating the adsorption of reaction radicals *COOH, and improving the charge transportation. This work might shed some light on designing more efficient SACs toward CO2 reduction through modification of their coordination environments.

5.
Dalton Trans ; 47(6): 1958-1965, 2018 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-29344588

RESUMEN

A 1-D infinite helical chain-like organic-inorganic hybrid arsenotungstate Na4H8[{Pr(H2O)2}2{As2W19O68}{WO2(mal)}2]·24H2O (mal = malate) (1) was prepared, which was characterized by elemental analyses, thermogravimetric (TG) analyses, IR spectroscopy, powder X-ray diffraction (PXRD) and X-ray single-crystal diffraction. Structural characterization revealed that 1 comprises the organo-functionalized [{As2W19O68}{WO2(mal)}2]18- polyanions hinged together by the Pr3+ ions forming a 1-D infinite helical chain-like architecture. The malate ligand may play a vital role to stabilize the structure of 1 by the formation of the five-membered W-O-C-C-O chelate ring. Solid state photoluminescence reveals that 1 features excitation wavelength-dependent emission properties, achieving a reversible emission color switching simply via changing the excitation wavelength. Time-resolved emission spectroscopy (TRES) indicates that the photoexcitation O → M ligand to metal charge transfer (LMCT) of arsenotungstate fragments can sensitize the Pr3+ ions through intramolecular energy transitions in 1.

6.
Dalton Trans ; 44(25): 11514-23, 2015 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-26032027

RESUMEN

Five members of a new family of polyoxometalate (POM)-ligated trinuclear lanthanoid (Ln) clusters with the general formula K20Li2[Ln3(µ3-OH)(H2O)8(AsW9O33)(AsW10O35(mal))]2·17H2O [Ln = Dy (1Dy), Tb (2Tb), Gd (3Gd), Eu (4Eu), and Sm (5Sm), mal = malate] have been synthesized, all of which consist of the dimeric {[Ln3(µ3-OH)(H2O)8(AsW9O33)[AsW10O35(mal)]}(11-) polyanion constructed from a {AsW9O33} and a {AsW10O35(mal)} building block linked by a tri-Ln cluster [Ln3(µ3-OH)(H2O)8](8+), where the two malate ligands play a key bridging role. The {AsW10O35(mal)} subunit can be viewed as the {AsW9O33} building block anchoring an additional tungsten center [WO2(mal)]. The electrospray ionization mass (ESI-MS) spectra indicate that the dimeric fragments of 1Dy and 2Tb are unstable, which are apt to produce the subunit [KH5Ln3(OH)(H2O)(AsW9O33)2](4-) in solution. The solid-state photoluminescence measurements display the yellowish green emission for 1Dy and 5Sm, green emission for 2Tb and reddish orange emission for 4Eu, which are attributed to the Ln(III) f-f electron transitions. Magnetic property studies indicate that 1Dy displays probable SMM behaviour with slow magnetization relaxation, whereas the weak antiferromagnetic interactions exist in two {Ln3} clusters for 2Tb-5Sm.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 138: 579-84, 2015 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-25541394

RESUMEN

A new 1-D linear chainlike terbium-substituted polyoxometalate [Tb(H2O)2(α-PW11O39)](4-) (1) has been synthesized in aqueous solution and characterized by elemental analysis, inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray powder diffraction (XRPD), IR spectrum, thermal analysis, electrospray ionization mass spectrometry (ESI-MS), and X-ray single-crystal diffraction. X-ray structural analysis reveals that 1 displays a 1-D linear chain containing [Tb(H2O)2(α-PW11O39)](4-) moieties. The Tb(III) cation incorporated into the monolacunary Keggin-type [α-PW11O39](7-) unit resides in a distorted monocapped triangular prismatic geometry and acts as a linker to join two adjacent [α-PW11O39](7-) units to form a 1-D chain structure. Solid-state photoluminescent property of 1 has been investigated at room temperature and the photoluminescent emission mainly results from the synergistic effect of the Tb(III) cation and the Na7[α-PW11O39] precursor. The ESI-MS spectrum of 1 confirms that the polyanion [Tb(H2O)(HPW11O39)](3-) is stable in aqueous solution.


Asunto(s)
Terbio/química , Compuestos de Tungsteno/química , Compuestos de Tungsteno/síntesis química , Cristalografía por Rayos X , Luminiscencia , Polvos , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Infrarroja , Termogravimetría
8.
Chem Commun (Camb) ; 49(45): 5189-91, 2013 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-23628910

RESUMEN

The nona-Cu(II)-containing tungstoarsenate(III) [H4{Cu(II)9As(III)6O15(H2O)6}(α-As(III)W9O33)2](8-) (1a) has been synthesized and characterized. Polyanion 1a comprises a unique, cylindrical {Cu(II)9As(III)6O15(H2O)6}(6+) cluster, which forms a large central cavity and is capped on either end by an [α-As(III)W9O33](9-) capping group. It exhibits remarkable activity against K562 leukaemia cells, as well as induces HepG2 cell apoptosis and autophagy.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Arseniatos/química , Arseniatos/farmacología , Cobre/química , Cobre/farmacología , Compuestos de Tungsteno/química , Compuestos de Tungsteno/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Humanos , Modelos Moleculares , Neoplasias/tratamiento farmacológico
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