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1.
Small ; 20(5): e2305888, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37726232

RESUMO

Achieving water splitting to produce green H2 , using the noble-metal-free MoS2 , has attracted huge interest from researchers. However, tuning the number of MoS2 layers precisely while obtaining small lateral sizes to surge the H2 -evolution rate is a tremendous challenge. Here, a bottom-up strategy is designed for the in situ growth of ultrasmall lateral-sized MoS2 with tunable layers on CdS nanorods (CN) by controlling the decomposition temperature and concentration of substrate seed (NH4 )2 MoS4 . Here, the bilayer MoS2 and CN coupling (2L-MoS2 /CN) exhibits the optimum photocatalytic activity. Compared to thicker MoS2 , the 2L-MoS2 has sufficient reduction capacity to drive photocatalytic H2 evolution and the ultrasmall lateral size provides more active sites. Meanwhile, the indirect bandgap, in contrast to the direct bandgap of the monolayer MoS2 , suppresses the carrier recombination transferred to 2L-MoS2 . Under the synergistic effect of both, 2L-MoS2 /CN has fast surface chemical reactions, resulting in the photocatalytic H2 -evolution rate of up to 41.86 mmol g-1 h-1 . A novel strategy is provided here for tuning the MoS2 layers to achieve efficient H2 evolution.

2.
Inorg Chem ; 62(32): 12822-12831, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37525121

RESUMO

Bismuth oxybromide (BiOBr) is a promising photocatalytic semiconductor material due to its unique hierarchical structure and band structure. However, its photocatalytic applications are restricted due to its narrow visible-light absorption range and poor photooxidation capability. In this study, BiOBr1-xIx-y with rich surface Br vacancies (BrVs-rich BiOBr1-xIx-y) was created via a facile indirect substitution strategy. Benefiting from the broadened visible-light response range and reduced recombination rate of photogenerated carriers, BiOBr1-xIx-y shows excellent visible-light photodegradation ability for high-concentration refractory contaminants, such as phenol, tetracycline, bisphenol A, rhodamine B, methyl orange, and even real wastewater. At the same time, the Br vacancies can regulate the band structure of BiOBr1-xIx-y and serve as trap states to promote charge separation, thus facilitating surface photoredox reactions. An in-depth investigation of the Br vacancy effect and photodegradation mechanism was conducted. This novel study revealed the significance of Br vacancies in enhancing the photocatalytic performance of BiOBr under visible light, providing a promising strategy for improving the utilization efficiency of sunlight in wastewater treatment.

3.
Inorg Chem ; 62(4): 1539-1548, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36642893

RESUMO

A proposed BiO(ClBr)(1-x)/2Ix-n solid solution containing abundant iodine vacancies has been constructed through a facile solvothermal treatment strategy. Fascinatingly, the iodine-vacancy BiO(ClBr)(1-x)/2Ix-n solid solution exhibits an outstanding visible-light photocatalytic degradation property for the environmentally hazardous pollutants of methyl orange, tetracycline, and phenol solutions, which is credited to the synergistic effect of iodine vacancies and the solid solution. By manipulating the molar ratios of Cl, Br, and I, the band structure of the solid solution attained is controlled, enabling the samples to maximize the harvest of visible light and to possess strong oxidation features. More importantly, the construction of iodine vacancies is bound to modulate the local surface atomic structure and promotes the efficiency of the separation of photogenerated carriers. Given these, the microstructure and physicochemical and photoelectrochemical properties of the photocatalysts are fully characterized in a series. In addition, the iodine-vacancy BiO(ClBr)(1-x)/2Ix-n solid solution has a stable crystal structure that permits favorable recyclability even after multiple cycles of degradation. This study sheds light on the significance of the simultaneous existence of vacancy and the solid solution for the enhanced performance of photocatalysts and opens up new insights for sustainable solar-chemical energy conversion.

4.
Inorg Chem ; 61(22): 8540-8549, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35603717

RESUMO

Photocatalytic technology has made a series of breakthroughs in environmental remediation, but the degradation performance of persistent heavy metal ions and organic pollutants is not particularly excellent. In addition, the layered structure of bismuth oxyhalides (BiOX, X = I, Br, and Cl) has been a popular material for photodegradation and photoelectrochemistry. Accordingly, with a view to construct a suitable band structure and control the surface structure, it is necessary to develop a strategy to synthesize a BiOCl1-xIn solid solution with halogen vacancies. In this study, halogen vacancies are in situ introduced into the BiOCl1-xIn solid solution through constructing chemical bonds between the hydroxyl groups in glycerol and the I ions during the growth process. The band of the halogen-vacancy BiOCl1-xIn solid solution is widened and active sites centered at halogen vacancies are formed in the direction favorable for the photocatalytic reaction, resulting in enhanced performance in the reduction of Cr(VI) and the oxidation of phenol. The results obtained can provide a new idea for the design of efficient photocatalysts by controlling the formation of halogen vacancies.

5.
Arthroscopy ; 29(4): 742-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23527593

RESUMO

PURPOSE: The purpose of our study was to retrospectively assess and analyze the incidence of deep venous thrombosis (DVT) after arthroscopically assisted anterior cruciate ligament reconstruction (ACLR) at our institution. METHODS: We conducted a retrospective analysis of 249 arthroscopic ACLRs performed in our hospital between February 2009 and February 2012. The surgical procedure was standardized in all the patients and was conducted by the same 2 surgeons. Quadrupled hamstring autograft was used in all the patients. No patient was given nonsteroidal anti-inflammatory drugs for the first 2 weeks after surgery. A unilateral contrast venography examination was performed on the third postoperative day. Patients were confined to bed once DVT was confirmed, followed by therapeutic doses of batroxobin. The proportion of patients with DVT was calculated. The significance of the association between clinical factors and postoperative DVT was determined. RESULTS: This study included 171 patients (123 men and 48 women), with a mean age (±SD) of 30.1 ± 10.0 years. DVT was detected in 24 patients (14.0%; 95% confidence interval, 8.8% to 19.3%). Body mass index (BMI), operative time, operator, and duration of tourniquet application were not significant risk factors for DVT. The risk of DVT was significantly higher in patients aged 35 years or older (P < .01). Higher risk for DVT was also identified in female patients (P < .05). Pulmonary embolism did not develop after thrombolytic therapy in any of the 24 patients with DVT after ACLR. CONCLUSIONS: The incidence of DVT in patients who underwent arthroscopic ACLR was 14% in this study. Female patients and those aged 35 years or older have a significantly higher risk of DVT developing after ACLR; thus thromboprophylaxis is advocated in these patients. LEVEL OF EVIDENCE: Level IV, therapeutic case series.


Assuntos
Reconstrução do Ligamento Cruzado Anterior/efeitos adversos , Trombose Venosa/etiologia , Adulto , Reconstrução do Ligamento Cruzado Anterior/métodos , Artroscopia , Feminino , Humanos , Incidência , Masculino , Estudos Retrospectivos , Tendões/transplante , Transplante Autólogo , Adulto Jovem
6.
J Colloid Interface Sci ; 635: 128-137, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36584613

RESUMO

Solar-driven hydrogen evolution over ZnO-ZnS heterostructures is considered as a promising strategy for sustainable-energy issues. However, the industrialization of this strategy is still constrained by suppressed carrier migration, rapid charge recombination, and the inevitable utilization of noble-metal particles. Herein, we envision a novel strategy of successfully introducing In2O3 into the ZnO-ZnS heterostructure. Benefiting from the optimized internal electric field and the charge carrier migration mode based on the direct Z-scheme, the interfacial elaborating In2O3-decorated ZnO/reduced graphene oxide (rGO)/ZnS heterostructure manifests smooth charge migration, suppressed electron-hole pair recombination, and increased surface active sites. More importantly, the in situ introduction of In2O3 optimizes the construction of the internal electric field, favoring directional light-triggered carrier migration. As a result, the light-induced electrons generated from the heterostructure can be efficiently employed for the hydrogen evolution reaction. Hence, this work would shed light on the in situ fabrication of noble-metal-free photocatalysts for solar-driven water splitting.

7.
Zhonghua Zhong Liu Za Zhi ; 25(1): 82-4, 2003 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-12678996

RESUMO

OBJECTIVE: To evaluate the blood supply of low density viable area of primary heptocellular carcinoma after transcatheter hepatic artery chemoembolization using lipiodol (LP-TACE), by helical dual-phase CT scanning and three dimensional CT (3DCT). METHODS: Thirty-four patients with primary heptocellular carcinoma after LP-TACE were examined by hepatic helical dual-phase CT. 3DCT model of the maximum intensity projection (MIP), surface shaded display (SSD) reconstruction of the hepatic artery and portal vein were simultaneously done in 5 cases. RESULTS: Viable tumor areas of 34 cases of primary heptocellular carcinoma after LP-TACE were divided into four types: peripheral, lateral, central and diffused types. Enhanced tumor vessel or tissue in viable tumor area was found during hepatic dual-phase in 17 cases, during hepatic artery-phase only in 8 and hepatic portal vein-phase only in 3. The viable tumor areas were found to have blood supply from the hepatic vein in 2 cases. The viable tumor area unenhanced during hepatic dual-phase was found in 6 cases. In 5 cases, the relation between the viable tumor area and branches of hepatic artery and portal vein was showed by MIP and SSD of hepatic artery and portal vein. CONCLUSION: Hepatic helical dual-phase CT scan with 3DCT is effective in evaluating the blood supply of viable tumor areas and the therapeutic effect of primary heptocellular carcinoma after LP-TACE.


Assuntos
Quimioembolização Terapêutica , Óleo Iodado , Neoplasias Hepáticas/terapia , Adulto , Idoso , Carcinoma Hepatocelular , Cateterismo , Meios de Contraste , Feminino , Artéria Hepática , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Espiral
9.
Ai Zheng ; 26(1): 73-7, 2007 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-17222372

RESUMO

BACKGROUND & OBJECTIVE: Angiography, a common method in evaluating blood supply of lung carcinoma, is invasive and complicated, with low success rate for bronchial artery, and could not assure to show all supply blood vessels at a time. This study was to explore clinical value of 16 slices spiral CT angiography with 3-dimensional CT (3DCT) and CT virtual endoscopy (CTVE) in diagnosing and evaluating supply blood vessels and blood supply of lung carcinoma, so as to find a non-invasive, safe, simple and effective method in diagnosing blood supply of lung carcinoma. METHODS: A total of 72 patients with pathologically proved lung carcinoma underwent 16 slices spiral CT angiography with 3DCT. Volume rendering (VR), maximum intensity projection (MIP), and surface shaded display (SSD) of supply blood vessels of lung carcinoma were used as 3DCT models. CTVE of bronchial artery was performed in 25 patients. Color VR of tumor lesion was performed in all patients. RESULTS: Supply blood vessels were showed in 68 patients, 59 of them showed only bronchial artery, 5 showed intercostals arteries, and 4 showed mixed types, including bronchial artery, intercostals arteries, or branch arteries of subclavian artery. The bronchial artery entered into enlarged mediastinal lymph nodes in 4 patients. CTVE well displayed the orifice and lumen of bronchial arteries in the 25 patients. The extent of red color of tumor lesion on VR color image were divided into 4 types: no color (n=11), light red (n=17), moderate red (n=32), and heavy red (n=12); the added CT values of tumor lesion after enhanced CT were (6.16+/-2.23) Hu, (15.71+/-3.13) Hu, (25.47+/-2.71) Hu, and (44.31+/-19.68) Hu, respectively. The corresponding rate between enhanced type and distributive type of red color on color VR was 86.1%. CONCLUSIONS: The 16 slices spiral CT angiography with 3DCT and CTVE could show clearly supply blood vessels and blood supply of lung carcinoma. It is a non-invasive, simple and effective method in evaluating and diagnosing blood supply of lung carcinoma.


Assuntos
Artérias Brônquicas/diagnóstico por imagem , Neoplasias Pulmonares/irrigação sanguínea , Tomografia Computadorizada Espiral/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia/métodos , Angioscopia/métodos , Feminino , Humanos , Imageamento Tridimensional , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
10.
Int J Neuropsychopharmacol ; 8(3): 451-5, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15817136

RESUMO

We previously reported that plasma levels of glycine, a co-agonist at N-methyl-D-asparate (NMDA)-type glutamate receptors, are decreased in patients with schizophrenia, and that glycine levels are negatively correlated with negative symptoms. The aim of the present study was to determine if glycine, or its ratio to serine, a precursor of glycine, predicts change in negative symptoms in subjects with schizophrenia during treatment with clozapine, an atypical antipsychotic drug with multiple effects on glutamatergic activity. Plasma levels of glycine, serine, and their ratio, were measured in 44 patients with schizophrenia who were subsequently treated with clozapine. Baseline glycine levels or glycine/serine ratios predicted the Scale for the Assessment of Negative Symptoms - Sum of the Global Scales and Avolition-Apathy after 6 wk of clozapine treatment. These results indicate the association of these amino acid measures with response to clozapine in terms of negative symptoms in patients with schizophrenia.


Assuntos
Antipsicóticos/uso terapêutico , Clozapina/uso terapêutico , Glicina/sangue , Esquizofrenia , Psicologia do Esquizofrênico , Serina/sangue , Adulto , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Escalas de Graduação Psiquiátrica , Análise de Regressão , Esquizofrenia/sangue , Esquizofrenia/tratamento farmacológico , Esquizofrenia/fisiopatologia
11.
Int J Neuropsychopharmacol ; 7(1): 1-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14720317

RESUMO

Previous studies have suggested decreased N-methyl-D-aspartate (NMDA)-type glutamate receptor function may contribute to increased negative symptoms in patients with schizophrenia. Consistent with this hypothesis, glycine, a co-agonist at NMDA receptors, has been reported to improve negative symptoms associated with the illness. This study was performed to determine if plasma levels of glycine or its ratio to serine, a precursor of glycine, are decreased in patients with schizophrenia compared to normal control subjects or patients with major depression. We also tested the hypothesis that these amino acids were correlated with negative symptoms in subjects with schizophrenia. Plasma levels of glycine, serine, and their ratio, were compared in 144 patients with schizophrenia, 44 patients with major depression, and 49 normal control subjects. All subjects were medication-free. Psychopathology was evaluated using the Brief Psychiatric Rating Scale (BPRS). Plasma glycine levels and glycine/serine ratios were decreased in patients with schizophrenia relative to control subjects and patients with major depression. By contrast, serine levels were increased in patients with schizophrenia compared to normal subjects but not compared to major depression. Patients with major depression also had increased plasma serine levels and decreased glycine/serine ratios compared to normal controls, but glycine levels were not different from those of normal controls. In subjects with schizophrenia, glycine levels predicted the Withdrawal-Retardation score (BPRS), whereas no such correlation was found in subjects with major depression. These results provide additional evidence that decreased availability of glycine may be related to the pathophysiology of negative symptoms. The decreases in plasma glycine levels support the evidence for an abnormality in the glutamatergic system in schizophrenia, and provide additional support for efforts to improve negative symptoms by augmentation of antipsychotic drugs with agonists at the glycine site of the NMDA receptor.


Assuntos
Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/psicologia , Glicina/sangue , Esquizofrenia/sangue , Psicologia do Esquizofrênico , Serina/sangue , Adulto , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/sangue , Transtornos Psicóticos/psicologia
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