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1.
Inorg Chem ; 63(13): 5931-5944, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38490189

RESUMO

Piezoelectric-photocatalysis is distinguished by its piezoelectricity as an external force that induces deformation within the catalyst to engender a polarized electric field compared to conventional photocatalysis. Herein, the piezoelectric photocatalyst BiOBr has been expertly synthesized via a plasma process and applied for piezoelectric-photocatalysis removal of uranium(VI) for the first time. The abundant surface oxygen vacancies (OVs) could induce a dipole moment and built-in electric field, which endows BiOBr with excellent separation and transport efficiency of photogenerated charges to actuate more charges to participate in the piezoelectric-photocatalytic reduction process. Consequently, under visible light and ultrasound (150 W and 40 kHz), the removal rate constant of OVs-BiOBr-30 (0.0306 min-1) was 2.4, 30.6, and 6 times higher than those of BiOBr (0.01273 min-1), ultrasound, or photocatalysis, respectively. The piezoelectric-photocatalytic synergy is also universal for BiOX (X = Cl, Br, or I) to accelerate the reduction rate of uranium(VI). This work highlights the role of piezoelectric-photocatalysis in the treatment of uranium-containing wastewater, which is of great significance for resource conservation and environmental remediation.

2.
Polymers (Basel) ; 15(12)2023 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-37376357

RESUMO

In practical application situations, a carbon fiber-reinforced polymer (CFRP) is often subjected to complex dynamic loadings. The effect of the strain rate on mechanical properties is very important for the CFRP design and product development. In this work, static and dynamic tensile properties of CFRP with different stacking sequences and ply orientations were investigated. The results showed that the tensile strengths of CFRP laminates were sensitive to the strain rate, while Young's modulus was independent of the strain rate. Moreover, the strain rate effect was related to the stacking sequences and ply orientations. The experimental results showed that the strain rate effects of the cross-ply laminates and quasi-isotropic-ply laminates were lower than that of the unidirectional-ply laminates. Finally, the failure modes of CFRP laminates were investigated. Failure morphology demonstrated that the differences in strain rate effects among cross-ply laminates, quasi-isotropic-ply laminates, and unidirectional-ply laminates were caused by the mismatch between the fiber and the matrix when the strain rate increased.

3.
Polymers (Basel) ; 15(11)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37299275

RESUMO

Weld lines are a common defect generated in injection molding, which apparently affects the performance of final products, but the available reports on carbon fiber-reinforced thermoplastics are still rather few. In this study, the effects of injection temperature, injection pressure, and fiber content on the mechanical properties of weld lines were studied for carbon fiber-reinforced nylon (PA-CF) composites. The weld line coefficient was also calculated by comparing specimens with and without weld lines. The tensile and flexural properties of PA-CF composites significantly increased with the rise of fiber content for specimens without weld lines, while injection temperature and pressure demonstrated slight influences on mechanical properties. However, the existence of weld lines had negative influences on the mechanical properties of PA-CF composites due to poor fiber orientation in weld line regions. The weld line coefficient of PA-CF composites decreased as fiber content increased, indicating that the damage of weld lines to mechanical properties increased. The microstructure analysis showed that there were a large number of fibers distributed vertically to flow direction in weld lines regions, which could not play a reinforcing role. In addition, increasing injection temperature and pressure facilitated fiber orientation, which improved the mechanical properties of composites with low fiber content, while weakening composites with high fiber content instead. This article provides practical information for product design containing weld lines, which helps to optimize the forming process and formula design of PA-CF composites with weld lines.

4.
Small ; 19(20): e2300003, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36807523

RESUMO

Designing highly efficient photocatalysts with rapid migration of photogenerated charges and surface reaction kinetics for the photocatalytic removal of uranium (U(VI)) from uranium mine wastewater remains a significant challenge. Inspired by natural photosynthesis, a biomimetic photocatalytic system is assembled by designing a novel hollow nanosphere MnOx @TiO2 @CdS@Au (MTCA) with loading MnOx and Au nano particles (Au NPs) cocatalysts on the inner and outer surfaces of the TiO2 @CdS. The spatially separated cocatalysts efficiently drive the photogenerated charges to migrate in opposite directions, while the Z-scheme heterogeneous shell further separates the interfacial charges. Theoretical calculation identifies multiple consecutive forward charge transfers without charge recombination within MTCA. Thus, MTCA could efficiently remove 99.61% of U(VI) after 15 min of simulated sunlight irradiation within 3 mmol L-1 NaHCO3 with 0.231 min-1 of the reduction rate constant, outperforming most previously reported photocatalysts. MTCA further significantly removes 91.83% of U(VI) from the natural uranium mining wastewater under sunlight irradiation. This study provides a novel approach to designing an ideal biomimetic photocatalyst for remediating environmental pollution.

5.
ChemistryOpen ; 9(8): 874-889, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32884883

RESUMO

The activity of pharmacologically active compounds can be increased by presenting a drug in a defined conformation, which fits exactly into the binding pocket of its target. Herein, the piperazine scaffold was conformationally restricted by substituted C2- or C3-bridges across the 2- and 6-position. At first, a three-step, one-pot procedure was developed to obtain reproducibly piperazine-2,6-diones with various substituents at the N-atoms in high yields. Three strategies for bridging of piperazine-2,6-diones were pursued: 1. The bicyclic mixed ketals 8-benzyl-6-ethoxy-3-(4-methoxybenzyl)-6-(trimethylsilyloxy)-3,8-diazabicyclo[3.2.1]octane-2,4-diones were prepared by Dieckmann analogous cyclization of 2-(3,5-dioxopiperazin-2-yl)acetates. 2. Stepwise allylation, hydroboration and oxidation of piperazine-2,6-diones led to 3-(3,5-dioxopiperazin-2-yl)propionaldehydes. Whereas reaction of such an aldehyde with base provided the bicyclic alcohol 9-benzyl-6-hydroxy-3-(4-methoxybenzyl)-3,9-diazabicyclo[3.3.1]nonane-2,4-dione in only 10 % yield, the corresponding sulfinylimines reacted with base to give N-(2,4-dioxo-3,9-diazabicyclo[3.3.1]nonan-6-yl)-2-methylpropane-2-sulfinamides in >66 % yield. 3. Transformation of a piperazine-2,6-dione with 1,4-dibromobut-2-ene and 3-halo-2-halomethylprop-1-enes provided 3,8-diazabicyclo[3.2.1]octane-2,4-dione and 3,9-diazabicyclo[3.3.1]nonane-2,4-dione with a vinyl group at the C2- or a methylene group at the C3-bridge, respectively. Since bridging via sulfinylimines and the one-pot bridging with 3-bromo-2-bromomethylprop-1-ene gave promising yields, these strategies will be exploited for the synthesis of novel receptor ligands bearing various substituents in a defined orientation at the carbon bridge.


Assuntos
Compostos Azabicíclicos/síntese química , Dicetopiperazinas/síntese química , Ciclização , Estrutura Molecular
6.
Eur J Med Chem ; 166: 318-327, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30731400

RESUMO

Axl is a new promising molecular target for antineoplastic therapies. A series of quinolone antibiotic derivatives were designed and synthesized as new selective Axl inhibitors. One of the most promising compound 8i bound tightly to Axl with a Kd value of 1.1 nM, and inhibited its kinase activity with an IC50 value of 26 nM. The compound also significantly inhibited the phosphorylation of Axl and dose dependently inhibited cell invasion and migration in TGF-ß1 induced MDA-MD-231 breast cancer cells. In addition, 8i demonstrated reasonable pharmacokinetic properties and exhibited extraordinary target selectivity over 468 kinases except for Flt3 (IC50 = 50 nM)), with a S(10) and S(35) value of 0.022 and 0.42 at 1.0 µM, respectively. Compound 8i may serve as a new valuable lead compound for future anticancer drug discovery.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Quinolonas/química , Quinolonas/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Animais , Antibacterianos/farmacocinética , Linhagem Celular Tumoral , Humanos , Concentração Inibidora 50 , Masculino , Inibidores de Proteínas Quinases/farmacocinética , Quinolonas/farmacocinética , Ratos , Ratos Sprague-Dawley , Receptor Tirosina Quinase Axl
7.
J Med Chem ; 59(14): 6807-25, 2016 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-27379978

RESUMO

Axl is a new potential target for anticancer drug discovery. A series of 4-oxo-1,4-dihydroquinoline-3-carboxamides were designed and synthesized as highly potent Axl kinase inhibitors. One of the most promising compounds, 9im, tightly bound with Axl protein and potently inhibited its kinase function with a Kd value of 2.7 nM and an IC50 value of 4.0 nM, respectively, while was obviously less potent against most of the 403 wild-type kinases evaluated at a relatively high concentration. The compound dose-dependently inhibited the TGF-ß1-induced epithelial-mesenchymal transition (EMT) and suppressed the migration and invasion of MDA-MB-231 breast cancer cells. In addition, 9im also demonstrated reasonable pharmacokinetics properties in rats and exhibited in vivo therapeutic effect on hepatic metastasis in a xenograft model of highly metastatic 4T1 murine breast cancer cells. Compound 9im may serve as a lead compound for new anticancer drug discovery and a valuable research probe for further biological investigation on Axl.


Assuntos
Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Quinolinas/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas/metabolismo , Quinolinas/síntese química , Quinolinas/química , Ratos , Ratos Sprague-Dawley , Receptores Proteína Tirosina Quinases/metabolismo , Relação Estrutura-Atividade , Cicatrização/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Receptor Tirosina Quinase Axl
8.
Bioorg Med Chem Lett ; 26(12): 2760-2763, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27155899

RESUMO

B-Raf(V600E) was an effective target for the treatment of human cancers. Based on a pan-Raf inhibitor TAK-632, a series of N-(4-aminopyridin-2-yl)amide derivatives were designed as novel B-Raf(V600E) inhibitors. Detailed structure-activity studies of the compounds revealed that most of the compounds displayed potent enzymatic activity against B-Raf(V600E), and good selectivity over B-Raf(WT). One of the most promising compound 4l exhibited potent inhibitory activity with an IC50 value of 38nM for B-raf(V600E), and displayed antiproliferative activities against colo205 and HT29 cells with IC50 values of 0.136 and 0.094µM, respectively. It also displayed good selectivity on both enzymatic and cellular assays over B-Raf(WT). These inhibitors may serve as lead compounds for further developing novel B-Raf(V600E) inhibitors as anticancer drugs.


Assuntos
Amidas/farmacologia , Antineoplásicos/farmacologia , Desenho de Fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Amidas/síntese química , Amidas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HT29 , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas B-raf/metabolismo , Relação Estrutura-Atividade
9.
Artigo em Chinês | MEDLINE | ID: mdl-26263782

RESUMO

OBJECTIVE: To understand the current situation of schistosomiasis health education in in Wuxi City where schistosomiasis transmission has been interrupted, so as to provide the evidence for formulating the health education strategies. METHODS: Face to face interviews and a professional designed questionnaire were used to collect the information of the current schistosomiasis health education and investigate the awareness of schistosomiasis knowledge in primary and middle schools and in communities. RESULTS: The total awareness rate of schistosomiasis knowledge was 87.7% among 873 students and the figure was 83.0% among 693 community residents. The students who studied in the schools with more than 1 class hour of schistosomiasis health education, completed schistosomiasis health education material or teaching plan, and implementing health education through multiple ways had higher knowledge awareness rates compared with the schools without (χ2 = 291.408, 709.622, 13.751, all P <0.001). The residents living in the communities with schistosomiasis health education through broadcast/TV or square propaganda had a higher knowledge awareness rate compared with the communities without (χ2= 90.772, 47.436, all P < 0.001). CONCLUSION: The awareness rates of schistosomiasis knowledge among both students and community residents in Wuxi City are low. Therefore, the schistosomiasis control health education should be strengthened.


Assuntos
Educação em Saúde , Esquistossomose/prevenção & controle , Adulto , Idoso , Conscientização , China/epidemiologia , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade
10.
Artigo em Chinês | MEDLINE | ID: mdl-25782256

RESUMO

OBJECTIVE: To understand the distribution and characteristics of historical Oncomelania hupensis snail environments and wetland environments in Wuxi City since 1952, so as to provide the evidence for formulating the monitoring strategy after the schistosomiasis transmission was interrupted. METHODS: A cross-sectional survey was conducted to collect the information of historical O. hupensis snail environments and wetland environments. Google Earth was used to present and analyze the distribution and characteristics of them. RESULTS: There were 2 124 historical O. hupensis snail environments in Wuxi City and the accumulative area was 2 995.7 hm2. In 2013, there were 61 surveillance sites of wetland with the area of 32.8 hm2; totally 1 695 snails were caught and no O. hupensis snails were found. CONCLUSION: The historical O. hupensis snail environments were distributed widely and covered a large area in Wuxi City. The surveillance should be focused on the key environments and wetland.


Assuntos
Distribuição Animal , Caramujos/crescimento & desenvolvimento , Animais , China , Meio Ambiente , Áreas Alagadas
11.
Artigo em Chinês | MEDLINE | ID: mdl-22379841

RESUMO

Laboratory diagnosis is one of the main means for diagnosis of echinococcosis. With the continuing evolvement of immunology and immunology technology, the laboratory diagnosis of echinococcosis obtained an encouraging progress, and the sensitivity and specificity of diagnostic tests for echinococcosis further improved. This review summarizes the current information concerning stool test, diagnostic antigen, and immunological diagnostic methods of echinococcosis.


Assuntos
Equinococose/diagnóstico , Testes Imunológicos/métodos , Animais , Anticorpos Anti-Helmínticos/imunologia , Equinococose/imunologia , Equinococose/parasitologia , Echinococcus/genética , Echinococcus/imunologia , Echinococcus/isolamento & purificação , Humanos , Sensibilidade e Especificidade
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