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1.
Dalton Trans ; 53(9): 4088-4097, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38314797

RESUMEN

Effectively harnessing solar energy for the conversion of CO2 into valuable chemical energy presents a viable solution to address energy scarcity and climate change concerns. Nonetheless, the limited light absorption and sluggish charge kinetics significantly hinder the photoreduction of CO2. In this study, we employed a facile sol-gel method combined with wetness impregnation to synthesize Cu-doped TiO2 coated with NiOx nanoparticles. Various characterizations verified the successful incorporation of Cu ions into the TiO2 crystal lattice and the formation of NiOx co-catalysts within the composites. The optimal performance attained with CTN-0.5 demonstrates an output of 11.85 µmol h-1 g-1 for CO and 9.51 µmol h-1 g-1 for CH4, which represent a 4.4-fold and 15.6-fold increase, respectively, compared to those achieved with pure TiO2. The induced Cu defect band broadens the light absorption by decreasing the conduction band edge of TiO2, while NiOx upshifts the valence band of TiO2 because of the interaction of valence orbitals. Light irradiation EPR and FTIR tests suggest that the collaboration of CuOx and NiOx promotes the formation of oxygen vacancies/defects and a rapid charge transfer pathway, thereby provides numerous active sites and electrons to enhance CO2 photoreduction performance.

2.
J Colloid Interface Sci ; 618: 300-310, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35344883

RESUMEN

As a renewable green energy, hydrogen has received widespread attention due to its huge potential in solving energy shortages and environment pollution. In this paper, a one-step solvothermal method was applied to grow ultra-thin g-C3N4 (UCN) nanosheets and NiS nanoparticles on the surface of ZnIn2S4 (ZIS). A ternary NiS/ZnIn2S4/ultra-thin-g-C3N4 composite material with dual high-speed charge transfer channels was constructed for the advancement of the photocatalytic H2 generation. The optimal ternary catalyst 1.5wt.%NiS/ZnIn2S4/ultra-thin-g-C3N4 (NiS/ZIS/UCN) achieved a H2 evolution yield reached to 5.02 mmolg-1h-1, which was 5.23 times superior than that of pristine ZnIn2S4 (0.96 mmolg-1h-1) and even outperform than that of the best precious metal modified 3.0 wt%Pt/ZnIn2S4 (4.08 mmolg-1h-1). The AQY at 420 nm could be achieved as high as 30.5%. The increased photocatalytic performance of NiS/ZIS/UCN could be ascribed to the type-I heterojunctions between intimated ZIS and UCN. In addition, NiS co-catalyst with large quantity of H2 evolution sites, could result in efficient photo-induced charges separation and migration. Furthermore, the NiS/ZIS/UCN composite exhibited excellent H2 evolution stability and recyclability. This work would also offer a reference for the design and synthesis of ternary co-catalyst with heterojunction composite for green energy conversion.

4.
Dalton Trans ; 47(42): 15155-15163, 2018 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-30311931

RESUMEN

Z-Scheme MoS2/g-C3N4 heterojunction photocatalysts were fabricated using a hydrothermal deposition procedure together with a calcination route, and then applied for CO2 photoreduction. Experimental results indicated that the 10% MoS2/g-C3N4 heterojunction displayed the best photocatalytic performance. Furthermore, the maximum CO yields of 58.59 µmol (g-cat)-1 under 7 h-visible light irradiation was up to 2.94 times that of the unadulterated g-C3N4. The enhanced photocatalytic performance of 10% MoS2/g-C3N4 catalyst was due to the favored visible light response, the efficient separation of photogenerated electron-hole pairs as well as its larger specific surface area.

5.
Zhonghua Fu Chan Ke Za Zhi ; 47(3): 179-84, 2012 Mar.
Artículo en Chino | MEDLINE | ID: mdl-22781068

RESUMEN

OBJECTIVE: To analyze the potential association between the single nucleotide polymorphisms (SNP) of the vascular endothelial growth factor (VEGF) gene with the risk of endometriosis by meta-analysis. METHODS: Published case-control studies about the influence of VEGF polymorphisms on endometriosis were searched and screened in Medline, the Cochrane library, China National Knowledge Internet (CNKI), Chinese Biological Medicine Disk (CBM), data base of Wanfang and Foreign Medical Journal Full-Text Service (FMJS). RevMan 5.0 software was used for meta-analysis. RESULTS: Finally, there were 9 literatures including 1610 endometrisis patients and 1643 controls cases, which were eligible for the criteria to investigating the VEGF SNP about -460C/T, +405C/G and +936C/T. The results of meta-analysis showed that there was no evidence for association between endometriosis and the VEGF -460C/T SNP in the genotype or allele frequencies distribution (P > 0.05). Significant differences were found between the frequencies distribution of VEGF +405CC genotype (P = 0.009, OR = 1.45, 95%CI: 1.10 - 1.91) and +405C allele (P = 0.020, OR = 1.19, 95%CI: 1.03 - 1.38), also between the +936CC genotype (P = 0.050, OR = 0.81, 95%CI: 0.66 - 1.00) and +936T allele (P = 0.040, OR = 1.20, 95%CI: 1.01 - 1.43). CONCLUSIONS: The VEGF +405C/G and +936C/T SNP may be associated with the risk of endometriosis. Women carrying the +405C or the +936T allele could significantly increase the risk of developing endometriosis.


Asunto(s)
Endometriosis/genética , Polimorfismo de Nucleótido Simple , Factor A de Crecimiento Endotelial Vascular/genética , Alelos , Estudios de Casos y Controles , Endometriosis/patología , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad/genética , Genotipo , Haplotipos , Humanos , Factores de Riesgo
6.
Nan Fang Yi Ke Da Xue Xue Bao ; 31(5): 772-6, 2011 May.
Artículo en Chino | MEDLINE | ID: mdl-21602122

RESUMEN

OBJECTIVE: To explore the role of Ca(2+) in nanosecond steep pulse (NSP)-induced apoptosis of human ovarian carcinoma cell line SKOV3 in vitro. METHODS: The early apoptotic rate of SKOV3 cells treated with NSP was detected by Annexin V/PI double staining and flow cytometry. MTT assay was used to detect the viability of the cells pretreated with BAPTA-AM (0, 25, 50 and 100 µmol/L) chelation for 1 h to increase the intracellular free Ca(2+) prior to NSP exposure, and the cell morphological changes and caspase 12 expression were detected using Hoechst 33342 staining and Western blotting, respectively. RESULTS: Flow cytometry showed that NSP induced early apoptosis of SKOV3 cells, and the optimal effect was achieved with the treatment parameter configuration of field strength of 90 kV/cm, pulse width of 100 ns, frequency of 1 Hz, and exposure time of 30 s. The highest early apoptotic rate and necrosis rate was (60.31∓5.67)% and (1.35∓0.39)%, respectively. Pretreatment with BAPTA-AM chelation prior to NSP exposure significantly increased the cell viability (P<0.05), and resulted also in lowered apoptosis rate and decreased expression of caspase 12 (P<0.05). CONCLUSION: NSP can induce apoptosis in SKOV3 cells. Increased intracellular free Ca(2+) functions as an important mediator in NSP-induced cell apoptosis, which may also involve Ca(2+)-mediated endo- plasmic reticulum pathway.


Asunto(s)
Apoptosis , Calcio/farmacología , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Calcio/química , Línea Celular Tumoral , Femenino , Humanos , Nanopartículas
7.
Chin Med Sci J ; 19(2): 116-9, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15250247

RESUMEN

OBJECTIVE: To investigate the potential role of preoperative adjuvant chemotherapy on early stage cervical squamous carcinoma with bulky tumor. METHODS: One hundred and forty-five patients with cervical squamous cancer stages Ib-IIa were investigated, among which 17 patients with bulky tumors (> or = 4 cm) were managed by cisplatin-based chemotherapy for 1-2 courses followed by radical hysterectomy and pelvic lymphadenectomy (BC group). The change of tumor size, pelvic lymph nodes metastasis, cervical wall invasion, the involvement of surgical specimen margin, and the blood loss during operation were assessed after operation and compared with those in 51 patients with bulky tumors (BN group) and 77 patients with small local tumors (S group) who underwent surgery directly. RESULTS: (1) The tumor size of 17 patients in BC group were decreased in various degrees after chemotherapy, with 13 patients of clinical effectiveness (76.47%). And the responsiveness pertained to neither histological differentiation nor size of local tumors. (2) Post-operative histology has showed that patients in BC and BN group have higher incidence of lymph node metastasis and deep cervical infiltration (5/68 and 3/68, respectively) than in S group (1/77 and 1/77, respectively) while with no statistical significance. (3) Blood loss during operation in BC group was less than BN and S group. (4) Seventeen patients, including those underwent surgeries of vaginal prolongation and/or ovarian transposition, appeared disease-free survival within the follow-up time. CONCLUSIONS: Most of patients with bulky early stage cervical squamous carcinoma are sensitive to cisplatin-based chemotherapy, which could greatly reduce local tumor size and in turn facilitate the following operation by well controlling blood loss.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/tratamiento farmacológico , Cisplatino/administración & dosificación , Neoplasias del Cuello Uterino/tratamiento farmacológico , Adulto , Bleomicina/administración & dosificación , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/secundario , Carcinoma de Células Escamosas/cirugía , Quimioterapia Adyuvante , Esquema de Medicación , Etopósido/administración & dosificación , Femenino , Humanos , Histerectomía , Metástasis Linfática , Persona de Mediana Edad , Estadificación de Neoplasias , Cuidados Preoperatorios , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/cirugía , Vincristina/administración & dosificación
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