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1.
Int J Biol Macromol ; 261(Pt 2): 129829, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38296134

RESUMO

Three-dimensional interpenetrating and hierarchically porous carbon material is an efficient catalyst support in water remediation and it is still a daunting challenge to establish the relationship between hierarchically porous structure and catalytic degradation performance. Herein, a highly porous silica (SiO2)/cellulose-based carbon aerogel with iron-based catalyst (FexOy) was fabricated by in-situ synthesis, freeze-drying and pyrolysis, where the addition of SiO2 induced the hierarchically porous morphology and three-dimensional interpenetrating sheet-like network with nitrogen doping. The destruction of cellulose crystalline structure by SiO2 and the iron-catalyzed breakdown of glycosidic bonds synergistically facilitated the formation of electron-rich graphite-like carbon skeleton. The unique microstructure is confirmed to be favorable for the diffusion of reactants and electron transport during catalytic process, thus boosting the catalytic degradation performance of carbon aerogels. As a result, the catalytic degradation efficiency of tetracycline under light irradiation by adding only 5 mg of FexOy/SiO2 cellulose carbon aerogels was as high as 90 % within 60 min, demonstrating the synergistic effect of photocatalysis and Fenton reaction. This ingenious structure design provides new insight into the relationship between hierarchically porous structure of carbon aerogels and their catalytic degradation performance, and opens a new avenue to develop cellulose-based carbon aerogel catalysts with efficient catalytic performance.


Assuntos
Carbono , Compostos Heterocíclicos , Carbono/química , Ferro/química , Dióxido de Silício , Celulose/química , Porosidade , Tetraciclina/química , Antibacterianos , Catálise
2.
J Colloid Interface Sci ; 630(Pt A): 772-782, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36283265

RESUMO

Immobilizing catalyst system faces the challenge of balancing catalysts stability and exposure of active site in water treatment. In this study, a novel in-situ synthesis of monoclinic phase of titanium dioxide (TiO2(B)) in cellulose-derived carbon aerogel (TCA) is proposed for processing multi-task in water treatment. The homogeneous gelation reaction supported the high dispersion of TiO2(B) in carbon skeleton. Meanwhile, TiO2 acts as crosslinker to reinforce cellulose network, then the grain refinement of amorphous TiO2 is limited to obtain TiO2(B) during carbonization. Benefiting from the reinforced structure, TCA remains the porous structure after carbonization and exposes more adsorption site than carbon aerogel blended with anatase particles (ACA). The adsorption performance of TCA are 837.3 mg/g, 1156.2 mg/g and 512.6 mg/g on methylene blue, malachite green and crystal violet, respectively. Compared with ACA, the superior interaction between TiO2 and graphite-like carbon improves the degradation rate of tetracycline from 1.3 × 10-3 min-1 to 8.6 × 10-3 min-1, and maintains the degradation efficiency in 3 rounds cyclic test. Besides, TCA also exhibits nearly twice to ACA on absorption capacity of different oil. This facile in-situ synthesis method offers a new insight in fabricating carbon aerogel immobilized photocatalysts system for multi-task in water treatment.


Assuntos
Nanocompostos , Purificação da Água , Carbono , Titânio/química , Nanocompostos/química , Celulose/química , Catálise
3.
Carbohydr Polym ; 296: 119957, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36087999

RESUMO

Hydrogel supported photocatalyst, an efficient strategy for water remediation suffers from compromised catalytic activity and insufficient stability. Herein, a robust cellulose-based composite hydrogel with zinc oxide (ZnO)/silica (SiO2) heterojunctions were fabricated by in-situ synthesis, where SiO2 not only acted as a cross-linking agent to enhance the mechanical strength and stability of hydrogel, but also promoted the photocatalytic properties of ZnO via transferring the electron-hole pairs due to its surface state. As a result, a significant improvement in the mechanical properties of cellulose-based composite hydrogel was achieved, exhibiting a high compressive strength of 703.4 kPa. Moreover, the degradation efficiency of methylene blue (MB) under light irradiation by cellulose-based composite hydrogel was 95 % in 120 min and the removal ratio maintained as high as 90 % after eight degradation cycles. This study provides a low-cost and facile method to construct new hydrogel supports with high stability and efficient photocatalytic properties.


Assuntos
Óxido de Zinco , Catálise , Celulose , Hidrogéis , Íons , Dióxido de Silício , Zinco
4.
J Insect Sci ; 18(2)2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29718488

RESUMO

Coptotermes suzhouensis (Isoptera: Rhinotermitidae) is a significant subterranean termite pest of wooden structures and is widely distributed in southeastern China. The complete mitochondrial DNA sequence of C. suzhouensis was analyzed in this study. The mitogenome was a circular molecule of 15,764 bp in length, which contained 13 protein-coding genes (PCGs), 22 transfer RNA genes, two ribosomal RNA genes, and an A+T-rich region with a gene arrangement typical of Isoptera mitogenomes. All PCGs were initiated by ATN codons and terminated by complete termination codons (TAA), except COX2, ND5, and Cytb, which ended with an incomplete termination codon T. All tRNAs displayed a typical clover-leaf structure, except for tRNASer(AGN), which did not contain the stem-loop structure in the DHU arm. The A+T content (69.23%) of the A+T-rich region (949 bp) was higher than that of the entire mitogenome (65.60%), and two different sets of repeat units (A+B) were distributed in this region. Comparison of complete mitogenome sequences with those of Coptotermes formosanus indicated that the two taxa have very high genetic similarity. Forty-one representative termite species were used to construct phylogenetic trees by maximum likelihood, maximum parsimony, and Bayesian inference methods. The phylogenetic analyses also strongly supported (BPP, MLBP, and MPBP = 100%) that all C. suzhouensis and C. formosanus samples gathered into one clade with genetic distances between 0.000 and 0.002. This study provides molecular evidence for a more robust phylogenetic position of C. suzhouensis and inferrs that C. suzhouensis was the synonymy of C. formosanus.


Assuntos
Genoma de Inseto , Genoma Mitocondrial , Isópteros/genética , Filogenia , Animais , Homologia de Sequência do Ácido Nucleico
5.
Acta Chim Slov ; 64(4): 825-831, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29318309

RESUMO

Three new complexes derived from 2-(4-(pyridin-2-yl)piperazin-1-yl)acetic acid (HL), [M(L)2(H2O)2] where M = CuII (1), ZnII (2) and CdII (3), have been synthesized and characterized by IR spectroscopy, elemental analysis and X-ray crystallography. The inhibitory activity of these three complexes against MAO-B was tested in vitro, and the molecular docking experiments were also carried out to rationalize their binding models. Both the experimental and docking simulation results indicated that complex 1 has the best inhibitory activity with IC50 value being 6.5 ± 0.31 µM.

6.
Acta Chim Slov ; 63(1): 165-72, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26970801

RESUMO

Two novel mononuclear complexes, [Cu(L)(2)(H(2)O)]·(2)H(2)O (1) and [Ni(L)(2)(H(2)O)(2)] (2) (HL = 2-[4-(4-fluorophenyl)piperazin-1-yl]acetic acid) were synthesized and structurally determined by single-crystal X-ray diffraction. Their inhibitory activities were tested in vitro against jack bean urease. Molecular docking was investigated to determine the probable binding mode. The experimental values and docking simulation exhibited that complex 1 had better inhibitory activity than the positive reference aceto hydroxamic acid (AHA), showing IC(50) value of 0.15 ± 0.08 µM, while 2 showed no inhibitory activity.


Assuntos
Complexos de Coordenação/síntese química , Inibidores Enzimáticos/síntese química , Simulação de Acoplamento Molecular , Elementos de Transição/química , Urease/antagonistas & inibidores , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Difração de Raios X
7.
Fa Yi Xue Za Zhi ; 30(1): 41-3, 46, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-24804383

RESUMO

OBJECTIVE: To discuss and summarize the major characteristics, autopsy examination, and scene investigation in infant homicide cases. METHODS: From 2008 to 2013 in Suzhou, the information of seven detected infant homicide cases were collected and analyzed. RESULTS: The criminal suspects were victims' mothers with young ages and pregnancies were premarital. Infant homicide cases occurred at the same location of the delivery. The infants died of mechanical asphyxia in the majority of the cases. Most bodies were naked and their umbilical cords were not cut by iatrogenic method and didn't connect with the bodies. CONCLUSION: The standardization of forensic investigation can improve the analysis and detection of infant homicide cases.


Assuntos
Medicina Legal , Homicídio , Asfixia , Autopsia , China , Criminosos , Morte , Humanos , Lactente , Estudos Retrospectivos
8.
Fa Yi Xue Za Zhi ; 29(1): 31-3, 36, 2013 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-23646500

RESUMO

OBJECTIVE: To summarize the solved homicide cases taking place in Suzhou city and to find out the characteristics and commonness of them in order to analyze the key points of investigation at the scene. METHODS: The data of 483 solved homicide cases occurring from January 2006 to March 2010 in the city were analyzed. RESULTS: Most cases involved 1 victim and 1 suspect, with young male adults dominated. Most of them were non-local residents. The majority of suspects were intentional by passion due to quarrel and dispute. The most common weapons were sharp instruments generally carried by the suspects. Mechanical asphyxia and mechanical injury were the two most common causes of death in these cases. CONCLUSION: The social characteristics of suspects, criminal motivation, injury instruments, distribution of injuries, cause of death, and manner of death in Suzhou showed similar general characteristics as the experience for detecting homicide cases in the future.


Assuntos
Vítimas de Crime/estatística & dados numéricos , Patologia Legal , Homicídio/estatística & dados numéricos , Ferimentos e Lesões/patologia , Adulto , Distribuição por Idade , Asfixia/mortalidade , Causas de Morte , Psicologia Criminal , Feminino , Humanos , Masculino , Estudos Retrospectivos , Distribuição por Sexo , Choque Hemorrágico/mortalidade , Fatores Socioeconômicos , Armas/estatística & dados numéricos , Ferimentos e Lesões/mortalidade
9.
Fa Yi Xue Za Zhi ; 21(3): 165-8, 2005 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-16259359

RESUMO

OBJECTIVE: To explore an method for diffuse axonal injury (DAI) diagnosis and injury time estimation, the changes of beta-APP immunoreactivity and to observe the morphology of axonal in different parts of brain after experimental DAI injury. METHODS: The animal models of DAI was established according to the Marmarou's method. Immunohistochemistry and Gless staining were performed to observe the changes of beta-APP expression and the morphology of axon with the time elapsed after the DAI injury. RESULTS: In the brain injury group, the morphologic changes of axon in brain stem were showed as twisted, broken and swellen at 0.5 h, and the myelin sheaths broken could be observed, the retraction ball was found at 12 h. Those morphology changes further progressed at 12h, reached to peack up to 1 d, then repaired at 3 d, and recovered at 10 d; Meanwhile the analysis of beta-APP immunoreactivity was also showed a time-dependent difference as fellows: beta-APP expression begin at 3h, increased its immunoreactivity at 12h, reached to maximize at 1 d, decreased after 3 d, returned to basal level at 10 d. CONCLUSIONS: The results suggest that beta-APP immunohistochemistry combine with Gless staining be sensitive methods for DAI diagnosis, they could discover the time-dependent changes of the axonal morphology.The changes beta-APP are quite regular and could be used for timing DAI injury.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Axônios/patologia , Tronco Encefálico/patologia , Lesão Axonal Difusa/diagnóstico , Lesão Axonal Difusa/metabolismo , Animais , Axônios/metabolismo , Tronco Encefálico/metabolismo , Lesão Axonal Difusa/patologia , Modelos Animais de Doenças , Feminino , Imuno-Histoquímica/métodos , Masculino , Ratos , Ratos Sprague-Dawley , Coloração e Rotulagem , Fatores de Tempo
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