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1.
J Ultrasound Med ; 42(7): 1587-1594, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36637120

RESUMO

OBJECTIVES: To analyze the risk factors of sulfur hexafluoride microbubble contrast agent intravasation during hysterosalpingo-contrast sonography (HyCoSy), and to explore a simple prediction model by the obvious clinical history. METHODS: This was a retrospective study included 299 infertility women who had undergone HyCoSy examination from July 1, 2018 to June 31, 2019. The factors were recorded, including age, endometrial thickness, balloon length, infertility type, history of intrauterine surgery, history of pelvic surgery, and tubal patency. The method of multivariate logistic regression analysis was adopted to analyze the risk factors affecting the contrast agent intravasation, and the receiver operating characteristic curves were plotted to test their efficacy. RESULTS: Secondary infertility, a history of intrauterine surgery, thin endometrial thickness, and tubal obstruction were all risk factors of the occurrence of intravasation (P < .05). And the area under the receiver operating characteristic curves of the multifactor-combined prediction model of the intravasation was significantly larger than that of single-factor. CONCLUSIONS: Sonographers and gynecologists should be familiar with the risk factors of intravasation and select the appropriate timing of HyCoSy toward reducing the occurrence of intravasation and other complications after thoroughly explaining and communicating with the patients.


Assuntos
Meios de Contraste , Infertilidade Feminina , Humanos , Feminino , Meios de Contraste/efeitos adversos , Hexafluoreto de Enxofre , Tubas Uterinas/diagnóstico por imagem , Histerossalpingografia/métodos , Estudos Retrospectivos , Microbolhas , Testes de Obstrução das Tubas Uterinas/métodos , Ultrassonografia/métodos , Fatores de Risco , Infertilidade Feminina/diagnóstico por imagem , Infertilidade Feminina/etiologia
2.
Int J Gen Med ; 15: 7709-7718, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36238541

RESUMO

Objective: To analyze the risk factors of the operators on contrast agent intravasation during hysterosalpingo-contrast sonography (HyCoSy). Methods: We retrospectively collected 399 infertile women who underwent HyCoSy by the same sonographer. These patients were divided into two groups according to the way how the assistants connected the syringe to the uterus radiography catheter to inject the contrast agent. We analyzed whether the use of different contrast bolus injection methods had any influence on the incidence of intravasation during HyCoSy. Results: There was no significant difference between the two groups with different cross-sectional areas of the syringe outflow tract in the risk variables for intravasation, but the intravasation rates of the two groups were different, 26.4% in group A and 17.1% in group B, P <0.05. The primary manifestation was that when both fallopian tubes were unobstructed, the intravasation rate of group B with smaller cross-sectional area of the outflow tract of the syringe was lower, and the difference was statistically significant. The inferences drawn from our physics model were also in line with the clinical results. Conclusion: The influence of different operators on the contrast agent intravasation rate of HyCoSy cannot be ignored. The assistants of HyCoSy examination should inject the contrast agent slowly and steady, and a needle can be used as a flow restrictor to control the flow into the uterine cavity per unit time, slow down the rising speed of intrauterine pressure, and avoid the accumulation of contrast agent in the uterine cavity, so as to reduce the intravasation caused by operator factors.

3.
Vet Sci ; 9(10)2022 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-36288183

RESUMO

Egg production in chickens is a quantitative trait. The aim of this study was to investigate the effect of promoter methylation of the Zona pellucida 2 (ZP2) gene on egg production. Real-time fluorescence quantification showed that the expression of the ZP2 gene in the ovaries of 300-day-old Jinghai yellow chickens in the high-laying group was significantly higher than that in the low-laying group (p < 0.01). A series of deletion fragments of the ZP2 gene promoter in Jinghai yellow chickens had different promoter activities in DF-1 cells, and the core region of the ZP2 gene promoter was found to be between −1552 and −1348. Four CpG islands in the promoter region of the ZP2 gene were detected by software prediction. The overall degree of methylation of the ZP2-1 amplified fragment was negatively correlated with mRNA expression to some extent (R = −0.197); the overall degree of methylation of the ZP2-2 amplified fragment was also negatively correlated with mRNA expression to some extent (R = −0.264), in which the methylation of methylcytosine (mC)-9, mC-20, and mC-21 sites was significantly negatively correlated with mRNA expression (p < 0.05). In addition, the mC-20 and mC-21 sites are located on the Sp1 transcription factor binding site, and it is speculated that these two sites may be the main sites for regulating transcription. In summary, the methylation sites mC-20 and mC-21 of the ZP2 gene may inhibit the binding of Sp1 and DNA, affect the transcription of the ZP2 gene, and then affect the number of eggs produced by the Jinghai yellow chickens.

5.
Phys Rev E ; 106(6-1): 064117, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36671114

RESUMO

We construct a microscopic model of low-dissipation engines by driving a Brownian particle in a time-dependent harmonic potential. Shortcuts to adiabaticity and shortcuts to isothermality are introduced to realize the adiabatic and isothermal branches in a thermodynamic cycle, respectively. We derive an analytical formula of the efficiency at maximum power with explicit expressions of dissipation coefficients under the optimized protocols. When the relative temperature difference between the two baths in the cycle is insignificant, this expression satisfies the universal law of efficiency at maximum power up to the quadratic term of the Carnot efficiency. For large relative temperature differences, the efficiency at maximum power tends to be 1/2. Furthermore, we analyze the issue of power at any given efficiency for general low-dissipation engines and then obtain the supremum of the power in three limiting cases, respectively. These expressions of maximum power at given efficiency provide the optimal relations between power and efficiency which are tighter than the results in previous references.


Assuntos
Simulação por Computador , Transferência de Energia , Termodinâmica
6.
Phytomedicine ; 60: 152957, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31128995

RESUMO

BACKGROUND: Inonotus obliquus, namely as Chaga mushroom, is a medicinal and edible fungus, which is widely used in food and medical fields. Inotodiol, a natural lanostane-type triterpenoid with remarkable pharmacological activities, was isolated from Inonotus obliquus, which its potential anti-tumor molecular mechanism was elaborated poorly. PURPOSE: The aim of the present study was to investigate the effect of Inotodiol on HeLa cell migration, invasion and apoptosis through p53-dependent pathway. STUDY DESIGN AND METHODS: The potential mechanisms of Inotodiol on HeLa cell anti-metastatic and pro-apoptosis via wound healing assay, trans-well invasion assay, flow cytometry, caspase-3 activity assay and western blot analysis were studied, as well as the involvement of p53 signaling pathway in anti-metastatic and pro-apoptosis of Inotodiol. Besides, the function of tumor suppressor p53 was further verified by small interfering RNA. RESULTS: Firstly, the cell viability assay showed that low-concentration of Inotodiol had no cytotoxicity to HeLa cells and whereas the concentration above 25 µM significantly inhibited HeLa cell growth and even induced apoptosis. This result was further demonstrated by cell proliferation and morphology assay. Secondly, in vitro wound healing and trans-well invasion assays reported that low-concentration treatment of Inotodiol significantly inhibited cells migration and invasion in a dose-dependent manner, the western blot analysis of matrix mettalloprotinase-2 (MMP2) and matrix mettalloprotinase-9 (MMP9) levels were also decreased. Moreover, Inotodiol notably induced tumor cell apoptosis by Annexin-V-FITC apoptosis assay, which is associated with activation pro-apoptotic proteins of PARP, cleaved caspase-3 and Bax expression, inhibition anti-apoptotic protein Bcl-2 expression. Finally, the anti-tumor activity of Inotodiol was attenuated by silencing p53 tumor suppressor, the result revealed that pre-treatment with p53-specific small interfering RNA (si-p53) markedly inhibited Intodiol-indeuced HeLa cell apoptosis and decreased the caspase-3 activity. What is more, the inhibitory effect of Inotodiol on tumor migration and invasion was blocked under p53 knockdown. CONCLUSION: To sum up, the present study indicated that Inotodiol possessed the potential to prevent malignant tumor migration and invasion, and it might be a natural active compound candidate for clinical treatment of human cervical cancer.


Assuntos
Agaricales/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Lanosterol/análogos & derivados , Proteína Supressora de Tumor p53/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Caspase 3/genética , Caspase 3/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Células HeLa , Humanos , Lanosterol/farmacologia , Invasividade Neoplásica , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética
7.
J Nat Med ; 72(3): 724-733, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29627895

RESUMO

Cisplatin (CDDP) is used in the treatment of non-small cell lung cancer (NSCLC), but due to the development of resistance, the benefit has been limited. Toosendanin (TSN) has shown therapeutic effects on NSCLC; however, the role of TSN on CDDP sensitization in NSCLC remains unknown. The antitumor effects of TSN and CDDP sensitization mediated by TSN were explored. TSN was added in various amounts to measure dose- and time-dependent cytotoxicity. Intracellular CDDP was detected by high-performance liquid chromatography. The protein levels of ATP7A, ATP7B, hCTR1, MRP-2, P-gp and Annexin A4 (Anxa4) were analyzed. The tests were conducted using normal NSCLC (A549 cell line) and CDDP-resistant cells (A549/DDP cell line). Anxa4 promotes CDDP resistance by regulating ATP7A, so Anxa4 was overexpressed and silenced and also transfected with pcMV6 or siRNA/ATP7A, respectively. Mechanistic investigations revealed that TSN decreased relative viability in NSCLC cells. Remarkably, TSN significantly enhanced CDDPsensitization in invalid doses. TSN downregulated Anxa4 expression, enhanced intracellular CDDP, and had no effect on MRP-2, P-gp, ATP7A, ATP7B or hCTR1. Subsequently, overexpression of Anxa4 led to a significant decrease in intracellular CDDP concentration. The adjustment of CDDP concentration regulated by TSN disappeared in Anxa4 or ATP7A-silenced cells. TSN also enhanced CDDP sensitization in single ATP7A-overexpressing cells, but had no effect on cells with simultaneous ATP7A overexpression and Anxa4 silencing. The present study suggests that TSN can mediate CDDP sensitization in NSCLC through downregulation of Anxa4.


Assuntos
Anexina A4/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cisplatino/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Cisplatino/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Neoplasias Pulmonares/patologia , Proteína 2 Associada à Farmacorresistência Múltipla , Transfecção
8.
Fetal Diagn Ther ; 44(4): 291-298, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29268259

RESUMO

OBJECTIVE: This study aimed to determine the significance of the venous drainage pattern of bronchopulmonary sequestration (BPS) in the prenatal course. METHODS: The venous drainage pattern of fetuses with BPS was determined with high-definition flow and confirmed by postnatal three-dimensional computed tomography angiography scan or autopsy. The volume of BPS lesions during gestation was recorded by the three-dimensional ultrasonographic Virtual Organ Computer-Aided Analysis software. The relationship between venous drainage pattern and prenatal characteristics was determined. RESULTS: Seventy-one fetuses were enrolled: 35 with systemic venous drainage (SVD) and 36 with pulmonary venous drainage (PVD). The volumes of BPS lesions significantly increased from the middle second trimester to the later second trimester in the SVD group. A marked decrease from the later second trimester to the third trimester was observed in the PVD group. The incidences of associated anomalies, hydrops, and polyhydramnios in the SVD group were 14.2, 23.3, and 33.3%, respectively, significantly higher than those in the PVD group (0, 0, and 5.6%, respectively). CONCLUSIONS: Our data indicate that SVD is correlated with a higher risk of associated anomalies and an unfavorable prenatal course in fetal BPS. Identification of the venous drainage pattern is of clinical significance in predicting the prenatal behavior of fetal BPS.


Assuntos
Sequestro Broncopulmonar/diagnóstico por imagem , Sequestro Broncopulmonar/patologia , Feminino , Humanos , Pulmão/diagnóstico por imagem , Poli-Hidrâmnios , Gravidez , Prognóstico , Ultrassonografia Pré-Natal
9.
Autophagy ; 11(2): 344-54, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25831014

RESUMO

Shiga toxins (Stxs) are a family of cytotoxic proteins that lead to the development of bloody diarrhea, hemolytic-uremic syndrome, and central nervous system complications caused by bacteria such as S. dysenteriae, E. coli O157:H7 and E. coli O104:H4. Increasing evidence indicates that macroautophagy (autophagy) is a key factor in the cell death induced by Stxs. However, the associated mechanisms are not yet clear. This study showed that Stx2 induces autophagic cell death in Caco-2 cells, a cultured line model of human enterocytes. Inhibition of autophagy using pharmacological inhibitors, such as 3-methyladenine and bafilomycin A1, or silencing of the autophagy genes ATG12 or BECN1 decreased the Stx2-induced death in Caco-2 cells. Furthermore, there were numerous instances of dilated endoplasmic reticulum (ER) in the Stx2-treated Caco-2 cells, and repression of ER stress due to the depletion of viable candidates of DDIT3 and NUPR1. These processes led to Stx2-induced autophagy and cell death. Finally, the data showed that the pseudokinase TRIB3-mediated DDIT3 expression and AKT1 dephosphorylation upon ER stress were triggered by Stx2. Thus, the data indicate that Stx2 causes autophagic cell death via the ER stress pathway in intestinal epithelial cells.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Toxinas Shiga/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Células Cultivadas , Células Epiteliais/citologia , Escherichia coli , Humanos , Camundongos Endogâmicos C57BL , Fator de Transcrição CHOP
10.
Ying Yong Sheng Tai Xue Bao ; 25(4): 931-9, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-25011282

RESUMO

The xylem sap flows of two pioneer tree species, i.e., Acacia mangium and Schima superba, in degraded hill lands of South China, were continually monitored with Granier' s thermal dissipation probes during 2004-2007 and 2008-2012, respectively, and their seasonal transpiration changes at different tree age levels were compared. The results showed that the annual transpiration of both species increased with tree ages, and S. superba demonstrated a higher value than A. mangium. The average annual whole-tree transpiration of S. superba (7014.76 kg) was higher than that of A. mangium (3704.97 kg). A. mangium (511.46-1802.17 kg) had greater seasonal variation than S. superba (1346.48-2349.35 kg). The standard regression coefficients (beta) of transpiration (Eh), photosynthetically active radiation (PAR) and vapor pressure deficit (VPD) for both species increased with soil moisture, suggesting the increase of soil moisture generated a greater sensitivity of plants to environmental factors. Partial correlation analysis revealed that soil moisture played an important role in the seasonal variation of transpiration of both species. The optimum soil moistures of S. superba and A. mangium were 0.22-0.40 and 0.29-0.30 (V/V), respectively, indicating the native pioneer species S. superba better adapted to water deficit compared with exotic pioneer species A. mangium.


Assuntos
Acacia/fisiologia , Transpiração Vegetal , Theaceae/fisiologia , Água/fisiologia , China , Ecossistema , Fotossíntese , Estações do Ano , Solo , Árvores , Xilema
11.
World J Gastroenterol ; 19(44): 8020-7, 2013 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-24307795

RESUMO

AIM: To investigate the expression of the hepatitis B virus (HBV) 1.3-fold genome plasmid (pHBV1.3) in an immortalized mouse hepatic cell line induced by SV40 T-antigen (SV40T) expression. METHODS: Mouse hepatic cells were isolated from mouse liver tissue fragments from 3-5 d old Kunming mice by the direct collagenase digestion method and cultured in vitro. The pRSV-T plasmid was transfected into mouse hepatic cells to establish an SV40LT-immortalized mouse hepatic cell line. The SV40LT-immortalized mouse hepatic cells were identified and transfected with the pHBV1.3 plasmid. The levels of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) in the supernatant were determined by an electrochemiluminescence immunoassay at 24, 48, 72 and 96 h after transfection. The expressions of HBsAg and hepatitis B c antigen (HBcAg) in the cells were investigated by indirect immunofluorescence analysis. The presence of HBV DNA replication intermediates in the transfected cells and viral particles in the supernatant of the transfected cell cultures was monitored using the Southern hybridization assay and transmission electronic microscopy, respectively. RESULTS: The pRSV-T plasmid was used to immortalize mouse hepatocytes and an SV40LT-immortalized mouse hepatic cell line was successfully established. SV40LT-immortalized mouse hepatic cells have the same morphology and growth characteristics as primary mouse hepatic cells can be subcultured and produce albumin and cytokeratin-18 in vitro. Immortalized mouse hepatic cells did not show the characteristics of tumor cells, as alpha-fetoprotein levels were comparable (0.58 ± 0.37 vs 0.61 ± 0.31, P = 0.37). SV40LT-immortalized mouse hepatic cells were then transfected with the pHBV1.3 plasmid, and it was found that the HBV genome replicated in SV40LT-immortalized mouse hepatic cells. The levels of HBsAg and HBeAg continuously increased in the supernatant after the transfection of pHBV1.3, and began to decrease 72 h after transfection. The expressions of HBsAg and HBcAg were observed in the pHBV1.3-transfected cells. HBV DNA replication intermediates were also observed at 72 h after transfection, including relaxed circular DNA, double-stranded DNA and single-stranded DNA. Furthermore, a few 42 nm Dane particles, as well as many 22 nm subviral particles with a spherical or filamentous shape, were detected in the supernatant. CONCLUSION: SV40T expression can immortalize mouse hepatic cells, and the pHBV1.3-transfected SV40T-immortalized mouse hepatic cell line can be a new in vitro cell model.


Assuntos
Antígenos Transformantes de Poliomavirus/biossíntese , DNA Viral/biossíntese , Genoma Viral , Vírus da Hepatite B/genética , Hepatócitos/virologia , Animais , Antígenos Transformantes de Poliomavirus/genética , Linhagem Celular Transformada , Proliferação de Células , Antígenos de Superfície da Hepatite B/biossíntese , Antígenos de Superfície da Hepatite B/genética , Antígenos E da Hepatite B/biossíntese , Antígenos E da Hepatite B/genética , Vírus da Hepatite B/crescimento & desenvolvimento , Hepatócitos/imunologia , Hepatócitos/metabolismo , Camundongos , Fatores de Tempo , Transfecção , Replicação Viral
12.
Acta Crystallogr C ; 69(Pt 11): 1332-5, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24192183

RESUMO

catena-Poly[[[4-amino-N-(quinoxalin-2-yl)benzenesulfonamidato]aquacadmium(II)]-µ-4-amino-N-(quinoxalin-2-yl)benzenesulfonamidato], [Cd(C14H11N4O2S)2(H2O)], has been synthesized hydrothermally and characterized by single-crystal X-ray diffraction, elemental analysis, fluorescence, IR and thermal analysis. Single-crystal X-ray analysis reveals that the complex is a one-dimensional zigzag chain structure, and the Cd(II) cation has a distorted octahedral coordination geometry formed by five N atoms from three different sulfaquinoxaline ligands and one O atom from a water molecule. The fluorescence spectrum reveals that the complex emits strong blue fluorescence and thermal analysis shows that the complex has high thermal stability.

13.
Acta Crystallogr C ; 69(Pt 10): 1096-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24096492

RESUMO

catena-Poly[[bis{4-[(pyrimidin-2-ylazanidyl)sulfonyl]aniline}cobalt(II)]-bis[µ-1,3-bis(pyridin-4-yl)propane]], [Co(C10H8N4O4S2)2(C13H14N2)]n or [Co(L)2(bpp)]n, crystallizes as a one-dimensional polymeric structure which is further stabilized by intermolecular hydrogen bonding. The refined Flack parameter, -0.001 (10), indicates that the model represents the correct absolute structure. Investigation of the thermal stability shows that the complex is stable up to 543 K. The structure is of interest with respect to its electrochemical properties in the reduction reaction of H2O2 to H2O.

14.
Yao Xue Xue Bao ; 44(5): 525-31, 2009 May.
Artigo em Chinês | MEDLINE | ID: mdl-19618731

RESUMO

To study the preparation, activity and targeting ability evaluation in vitro on epigallocatechin-3-gallate (EGCG) bovine serum albumin nanoparticles targeting to PC-3 cells, the folate mediated EGCG bovine serum albumin nanoparticles (FA-EGCG-BSANP) were prepared by desolvation process. The morphology and particle size of the nanoparticles were determined by atomic force microscope (AFM). HPLC was used to analyse the entrapment efficiency and drug loading rate of EGCG The amount of folate conjugation on the BSANP was determined by quantitative ultraviolet (UV) spectrophotometer analysis. The targeting ability to PC-3 was observed using laser scanning confocal microscope (LSCM) and fluorophotometer microscope. And the activity of FA-EGCG-BSANP was mensurated by MTT method. The morphology and particle size distribution of FA-EGCG-BSANP were uniform and even with the mean particle size of 200 nm. The entrapment efficiency and loading rate of EGCG were (81.5 +/- 1.8) % and (29.3 +/- 0.6) %, respectively, and the amount of folate conjugation was 18.363 microg x mg(-1) BSA. The FA-EGCG-BSANP uptakes by cultured PC-3 cells were 23.65 times the amount of EGCG-BSANP in a concentration dependant manner. The lethality of PC-3 cells treated with FA-EGCG-BSA was 82.8%, while those treated with EGCG and EGCG-BSANP were 58.6% and 55.1%, respectively. And lethality of PC-3 cells was positively correlated with the nanoparticles uptake amount. FA-EGCG-BSANP can significantly promote EGCG to PC-3 cells sites and improve their efficacy, which is considered to an experimental foundation for further research on its activity, targeting ability and metabolism in vivo.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Catequina/análogos & derivados , Sistemas de Liberação de Medicamentos/métodos , Neoplasias da Próstata/metabolismo , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Catequina/administração & dosagem , Catequina/farmacocinética , Catequina/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Portadores de Fármacos , Composição de Medicamentos , Ácido Fólico/administração & dosagem , Ácido Fólico/química , Ácido Fólico/farmacocinética , Humanos , Masculino , Nanopartículas , Tamanho da Partícula , Neoplasias da Próstata/patologia , Soroalbumina Bovina/química , Soroalbumina Bovina/farmacocinética , Soroalbumina Bovina/farmacologia
15.
Huan Jing Ke Xue ; 27(8): 1591-5, 2006 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17111617

RESUMO

SPR electrode was used in Electrio-Fenton treatment on the effluent from biological and coagulative treatments of solid waste incinerator leachate, at the same time, the kinetics model for the COD effluent concentration were set up. The result indicated that the disposal curve of COD confirm to the pseudo third order kinetics, and the formula is c(t) = (2kt + c(0)(-2))(-0.5), in which the c(t) is the COD concentration of treatment effluent. With the statistical analysis to the disposal curve of COD from Electro-Fenton treatment in different conditions, the experience mathematics model of k value was set up, in which the current density, pH value and COD concentration of influent are effective factors. Moreover, with the comparison between the simulative COD of effluent and the experimental results, it was showed that this kinetic model could be used to investigate the COD disposal efficiency of Electro-Fenton treatment on the effluent from biological and coagulative treatments of solid waste incinerator leachate preferably.


Assuntos
Incineração , Eliminação de Resíduos/métodos , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Catálise , Cloretos , Eletroquímica , Compostos Férricos/química , Peróxido de Hidrogênio/química , Ferro/química , Cinética , Modelos Teóricos , Compostos Orgânicos/química , Poluentes Químicos da Água/química
16.
J Environ Sci (China) ; 18(6): 1254-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17294974

RESUMO

Under the optimal condition of copper ions adsorption on yeast,we found some different effects among static adsorption, shaking adsorption and negative pressure cavitation adsorption, and the methods of yeast with different pretreatments also affect adsorption of copper ions. At the same time, the change of intercellular pH before and after adsorption of copper with BCECF was studied. The copper distribution was located by using PhenGreen (dipotassium salt and diacetate), and the surface of yeast was observed by an atomic force microscope. The results showed that negative pressure cavitation can improve bioadsorption capacity of copper ions on yeast. However, the yeasts' pretreatment has a higher effect on bioadsorption. It indicates that heavy metal bioadsorption on yeast has much relation with its cellular molecule basis. With the adsorping, the intercellular pH of yeast increased gradually and changed from acidity to alkalescence. These results may suggest that negative pressure cavitation can compel heavy metals to transfer from the cell surface into inside cell and make the surface of yeast coarse.


Assuntos
Candida/química , Cobre/química , Poluentes Ambientais/química , Adsorção , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Microscopia de Força Atômica , Pressão Parcial
17.
Huan Jing Ke Xue ; 25(3): 53-6, 2004 May.
Artigo em Chinês | MEDLINE | ID: mdl-15327253

RESUMO

By using a trickle bed reactor which was designed by the authors, the catalytic wet air oxidation reaction of phenol on CuO/gamma-Al2O3 catalyst was studied. The results showed that in mild operation conditions (at temperature of 180 degrees C, pressure of 3 MPa, liquid feed rate of 1.668 L x h(-1) and oxygen feed rate of 160 L x h(-1)), the removal of phenol can be over 90%. The curve of phenol conversion is similar to "S" like autocatalytic reaction, and is accordance with chain reaction of free radical. The kinetic model of pseudo homogenous reactor fits the catalytic wet air oxidation reaction of phenol. The effects of initial concentration of phenol, liquid feed rate and temperature for reaction also were investigated.


Assuntos
Fenol/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Catálise , Cinética , Oxirredução , Fenol/análise
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