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1.
ACS Omega ; 9(17): 19679-19689, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38708216

RESUMO

Pyrometallurgy is the most effective way to comprehensively utilize boron-bearing iron concentrate, and there is an urgency for an environmentally friendly and efficient method to achieve the prereduction of boron-bearing iron concentrate. In this study, the mechanism and kinetics of isothermal hydrogen reduction of boron-bearing iron concentrate in a fluidized bed at 500-570 °C were discussed. The reduction degree was quantified in combination with the online gas composition analysis technique, and the phase and microstructure of the reduced products were characterized. The results exhibited that the apparent activation energy remained constant during the whole reduction process, with average values of 50.67 and 48.08 kJ/mol calculated by the model-free and model-fitting methods, respectively, and the reaction was controlled by the contracting sphere model. The formation of a microporous metallic iron facilitated the rapid penetration of hydrogen to the reaction interface. Therefore, the intrinsic chemical reaction at the interface determined the whole reaction process.

2.
Sci Rep ; 14(1): 9960, 2024 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-38693222

RESUMO

The pathogenesis of aortic dissection (AD), an aortic disease associated with high mortality, involves significant vascular inflammatory infiltration. However, the precise relationship between perivascular adipose tissue (PVAT) and aortic dissection remains incompletely understood. The objective of this study is to investigate the role of PVAT inflammation in the pathogenesis of aortic dissection and identify novel therapeutic targets for this disease. The mouse model of aortic dissection was established in this study through intraperitoneal injection of Ang II and administration of BAPN in drinking water. Additionally, control groups were established at different time points including the 2-week group, 3-week group, and 4-week group. qPCR and immunohistochemistry techniques were employed to detect the expression of inflammatory markers and RUNX1 in PVAT surrounding the thoracic aorta in mice. Additionally, an aortic dissection model was established using RUNX1 knockout mice, and the aforementioned indicators were assessed. The 3T3-L1 cells were induced to differentiate into mature adipocytes in vitro, followed by lentivirus transfection for the knockdown or overexpression of RUNX1. The study aimed to investigate the potential cell-to-cell interactions by co-culturing 3T3-L1 cells with A7r5 or RAW264.7 cells. Subsequently, human aortic PVAT samples were obtained through clinical surgery and the aforementioned indicators were detected. In comparison to the control group, the aortic dissection model group exhibited decreased expression of MMP-2 and NF-κB in PVAT, while TNF-α and RUNX1 expression increased. Suppression of RUNX1 expression resulted in increased MMP-2 and NF-κB expression in PVAT, along with decreased TNF-α expression. Overexpression of RUNX1 upregulated the expression levels of NF-Κb, MMP-2, and TNF-α in adipocytes, whereas knockdown of RUNX1 exerted an opposite effect. Macrophages co-cultured with adipocytes overexpressing RUNX1 exhibited enhanced CD86 expression, while vascular smooth muscle cells co-cultured with these adipocytes showed reduced α-SMA expression. In human samples, there was an increase in both RUNX1 and MMP-2 expression levels, accompanied by a decrease in TNF-α and NF-Κb expression. The presence of aortic dissection is accompanied by evident inflammatory alterations in the PVAT, and this phenomenon appears to be associated with the involvement of RUNX1. It is plausible that the regulation of PVAT's inflammatory changes by RUNX1/NF-κB signaling pathway plays a role in the pathogenesis of aortic dissection.


Assuntos
Tecido Adiposo , Dissecção Aórtica , Subunidade alfa 2 de Fator de Ligação ao Core , Modelos Animais de Doenças , Inflamação , NF-kappa B , Animais , Humanos , Masculino , Camundongos , Células 3T3-L1 , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Dissecção Aórtica/metabolismo , Dissecção Aórtica/patologia , Dissecção Aórtica/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Inflamação/metabolismo , Inflamação/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Células RAW 264.7 , Transdução de Sinais
3.
J Environ Manage ; 356: 120594, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503229

RESUMO

Almost all iron ore tailings (IOTs) required activation prior to use as SCMs, which limited their application in building materials. This study investigated HMPT-IOTs and discovered that they possess latent hydraulic and pozzolanic properties. In order to better utilize as SCM, mechanical properties, hydration reactions, hydration products, microstructure, and pores were comprehensively studied through mechanical tests, hydration heat tests, XRD, SEM, TG, and MIP. The results show that when HMPT-IOTs replace cement at 10 wt%, 20 wt% and 30 wt%, the compressive strength at 28 days is 41.9 MPa, 47.9 MPa and 37.5 MPa, respectively. When the substitution amount reaches 30 wt%, it will reduce the cumulative heat of hydration and promote early hydration reactions. The main hydration products are ettringite and Ca(OH)2. As the nucleation site of C-S-H, hydration products are interconnected, making the microstructure denser. At this substitution level, Ca(OH)2 consumption was about 2% at 28 days of age. Simultaneously, the total pore volume was only 0.01 mL/g greater than that of the control group, and the number of micropores and transition pores decreased by approximately 3%.


Assuntos
Materiais de Construção , Hidrogênio , Força Compressiva , Minerais , Ferro
4.
ACS Omega ; 8(44): 41232-41242, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37970053

RESUMO

Rapid formation of the CO2 hydrate can be significantly induced by the gaseous thermodynamic promoter 1,1,1,2-tetrafluoroethane(R134a) due to the mild phase equilibrium conditions, although the formation mechanism and dynamic behavior are not clear. Therefore, a visual experimental system was developed to study the effects of different concentrations of R134a on the induction time, gas consumption, and growth morphology of the CO2 hydrate. At the same time, the combined effects under stirring and sodium dodecyl sulfate (SDS) systems were also studied. In addition, visualization and experimental model diagrams were combined to explain the fast formation mechanism of the R134a/CO2 hydrate. The results show that the CO2 hydrate average conversion rate was increased by more than 63% with the addition of mixed trace R134a(7%). A special phenomenon is found that two temperature peaks appear on the hydrate formation temperature curve, corresponding to two different stages of hydrate formation when stirring or SDS is added to the mixed gas reaction system. Furthermore, the gas consumption in stirring and SDS systems increases by 9 and 44%, respectively. Finally, it is also found that the R134a/CO2 mixed hydrate formed under the action of SDS has a "capillary" mechanism, which provides a gas-liquid phase exchange channel and a large number of nucleation sites for CO2 hydrate, thus promoting the formation of CO2 hydrate. This paper provides a novel, simple, and efficient method for CO2 hydrate gas storage technology.

5.
World J Gastroenterol ; 29(20): 3119-3132, 2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37346158

RESUMO

BACKGROUND: Pancreatic mucinous cystic neoplasms (MCNs) represent one of the precursor lesions of pancreatic ductal adenocarcinoma, and their detection has been facilitated by advances in preoperative imaging. Due primarily to the rarity of MCNs, however, there is limited knowledge regarding the prognostic variables and high-risk factors for malignant transformation. A more comprehensive and nuanced approach is necessary to fill this gap and provide a basis for improved treatment decisions and patient outcomes. AIM: To investigate the high-risk factors associated with malignant MCNs and to explore the prognostic factors of MCN with associated invasive carcinoma (MCN-AIC). METHODS: All cases of resected MCNs from a single high-volume institution between January 2012 and January 2022 were retrospectively reviewed. Only cases with ovarian-type stroma verified by progesterone receptor staining were included. Preoperative features, histological findings and postoperative course were documented. Multivariate logistic regression was employed to investigate variables related to malignancy. Survival analysis was performed using the Kaplan-Meier curve, and the prognostic factors were assessed to evaluate the postoperative course of patients with MCN-AIC. RESULTS: Among the 48 patients, 36 had benign MCNs, and 12 had malignant MCNs (1 high-grade atypical hyperplasia and 11 MCN-AIC). Age, tumour size, presence of solid components or mural nodules and pancreatic duct dilatation were identified as independent risk factors associated with malignancy. The follow-up period ranged from 12 mo to 120 mo, with a median overall survival of 58.2 mo. Only three patients with MCN-AIC died, and the 5-year survival rate was 70.1%. All 11 cases of MCN-AIC were stage I, and extracapsular invasion was identified as a prognostic factor for poorer outcomes. CONCLUSION: The risk factors independently associated with malignant transformation of MCNs included age, tumour size, presence of solid components or mural nodules, and pancreatic duct dilatation. Our study also revealed that encapsulated invasion was a favourable prognostic factor in MCN-AIC patients.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Císticas, Mucinosas e Serosas , Neoplasias Pancreáticas , Receptores de Progesterona , Humanos , Carcinoma Ductal Pancreático/epidemiologia , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/cirurgia , População do Leste Asiático , Neoplasias Císticas, Mucinosas e Serosas/epidemiologia , Neoplasias Císticas, Mucinosas e Serosas/patologia , Neoplasias Císticas, Mucinosas e Serosas/cirurgia , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Prognóstico , Estudos Retrospectivos
6.
ACS Omega ; 7(4): 3618-3625, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35128269

RESUMO

Refractory gold ore is usually affected by the associated carbonaceous matter through the preg-robbing effect, which is eliminated by oxidation roasting, followed by leaching, to achieve a satisfactory gold leaching efficiency. Roasting-leaching experiments, pore structure measurements, scanning electron microscopy (SEM), and X-ray diffraction are used to explore the structural evolution of pores on the surface and its effect on the leaching performance. Pores with optimal sizes were obtained by roasting at 650 °C for 2.0 h with a ventilation of 0.6 m3/h; approximately 92.55% gold could be recovered under these conditions. A porous structure observed by SEM became more compact as the temperature further increased to 850 °C. The formation of CaSiO3 and CaSO4 in pores led to pore shrinkage. The mechanism of oxidation roasting, followed by cyanide leaching, was schematically analyzed and revealed the effects of pore structural evolution and phase transformation on the leaching efficiency.

7.
ACS Omega ; 6(27): 17599-17608, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34278145

RESUMO

In the process of sulfuric acid curing-leaching vanadium-bearing stone coal, the curing effect is very important. The main purpose of this study is to capture the difference in the curing effect between coarse and fine stone coal, with a V2O5 content of 0.88%. In this work, the effects of various factors such as sulfuric acid concentration, curing time, curing temperature, and different agents for curing on the leaching efficiency of vanadium were investigated by the comparison of the two size fractions. The results showed that the leaching efficiency of vanadium was 87.65% under the optimum curing conditions of 25 wt % sulfuric acid, curing time of 8 h, and curing temperature of 130 °C. It was clearly found that, under the same curing condition, the curing effect of fine stone coal was better than that of coarse stone coal. The penetration part of stone coal particles by sulfuric acid was loose, while the non-penetration part was dense after acid curing. Moreover, the penetration depth of sulfuric acid into the particles was mainly 0.5-0.7 mm on average. There was more sericite/illite in coarse leaching residues, which were mostly dense and hard carbonaceous siliceous slate. Thus, sulfuric acid was difficult to penetrate into and reach the interior of the particle, which resulted in that the leaching efficiency of coarse vanadium-bearing stone coal ore was lower than that of fine vanadium-bearing stone coal ore.

8.
J Hazard Mater ; 420: 126542, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34265654

RESUMO

Red mud (RM) is the major waste material with strong alkaline discharged which is during the alumina extraction process. The global stock of RM has exceeded 4 billion tons and its disposal as a solid waste has always been a thorny environmental problem. However, RM is widely considered to be a potential resource due to its high content of valuable metal components such as iron. High-iron RM is rich in iron and can potentially become a valuable resource if the iron can be extracted effectively. It is of great research value and profound significance to recover iron from high-iron RM. This paper systematically reviews the iron recovery methods for resource utilization of high-iron RM, and divides the technology of iron recovery from high-iron RM into three aspects: physical separation method, pyrometallurgy method (reduction smelting and reduction roasting) and hydrometallurgy method (acid leaching). The basic principles and effect of iron extraction of the above technologies are summarized respectively, and the advantages and disadvantages of different technologies are compared. It is pointed out that the feasibility and economic cost are the main factor restricting the industrial application of these technologies. Therefore, it is of great significance to overcome various problems and difficulties, and develop innovative processes and technologies, which can realize the recycling and utilization of iron in high-iron RM and realize the reduction of RM emission at the same time.


Assuntos
Ferro , Reciclagem , Óxido de Alumínio , Metais , Tecnologia
9.
Cancer Manag Res ; 13: 9477-9487, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35002325

RESUMO

PURPOSE: The aim of this study was to explore potential gene therapy targets for triple-negative breast cancer (TNBC). PATIENTS AND METHODS: Three gene expression profiles (GSE64790, GSE62931, and GSE38959) from the Gene Expression Omnibus (GEO) database were analyzed. The GEO2R analysis tool was used to screen for differentially expressed genes (DEGs) between TNBC and normal tissues, followed by Gene Ontology functional annotation and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis of the DEGs. The protein-protein interaction network of DEGs was visualized using Metascape to identify the core genes. Subsequently, transcriptional data for the core genes in patients with breast cancer were investigated in the ONCOMINE database. Kaplan-Meier survival analysis was used to evaluate the prognostic value of core gene expression levels in patients with TNBC. Finally, the clinicopathological and long-term follow-up data of 39 patients with TNBC were retrospectively analyzed at the First Affiliated Hospital of the Bengbu Medical College between January 2014 and July 2020. Immunohistochemistry was used to evaluate the expression and subcellular localization of CCNB2 in TNBC tissues. RESULTS: A total of 66 DEGs were identified between TNBC and normal tissues, including 33 upregulated and 33 downregulated genes in TNBC. Furthermore, a potential protein complex was identified for five core genes. The high expression of these core genes, especially the overexpression of CCNB2, was correlated with a poor prognosis of patients with TNBC. The CCNB2 protein was expressed in the cytoplasm, and its expression was significantly higher in TNBC tissues than that in the adjacent nontumor tissues. Overall survival of patients was significantly correlated with the expression of CCNB2 (p < 0.05). CONCLUSION: CCNB2 may play a crucial role in the development of TNBC and has the potential to be used as a prognostic biomarker for TNBC.

10.
J Hazard Mater ; 394: 122579, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32283382

RESUMO

Red mud is a type of solid waste derived from the alumina extraction process. It can be considered as a secondary resource for recovering iron values because of its high content of ferric oxide. In this study, an innovative technology called suspension magnetization roasting (SMR) was applied to treat red mud to recycle iron. Based on the lab-scale experimental basis, we adopted the single factor method to perform the semi-industrial scale experiments. Under the optimum conditions, the recovery and grade of iron in the iron concentrate were 95.22 % and 55.54 %, respectively. Chemical phase analysis, vibrating sample magnetometer, and XRD combined with Mössbauer spectroscopy were employed to assess the characteristics of red mud and roasted products. Occupancy of Fe content in magnetite was raised to 89.91 % in SMR products from 0.75 % in the red mud; saturation magnetization was enhanced from 0.40 A·m2/kg to 32.44 A·m2/kg; and the hematite and goethite phase were transformed into Fe3O4 (A), Fe3O4 (B) and γ-Fe2O3 phase. In addition, transmission electron microscopy analysis revealed that both magnetite and maghemite were found in the roasted product. This study demonstrates that SMR is a promising technology for the recovery of iron from red mud.

11.
Fish Shellfish Immunol ; 95: 248-258, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31654767

RESUMO

Universal stress proteins (Usps) exist ubiquitously in bacteria and other organisms. Usps play an important role in adaptation of bacteria to a variety of environmental stresses. There is increasing evidence that Usps facilitate pathogens to adapt host environment and are involved in pathogenicity. Edwardsiella piscicida (formerly included in E. tarda) is a severe fish pathogen and infects various important economic fish including tilapia (Oreochromis niloticus). In E. piscicida, a number of systems and factors that are involved in stress resistance and pathogenesis were identified. However, the function of Usps in E. piscicida is totally unknown. In this study, we examined the expressions of 13 usp genes in E. piscicida and found that most of these usp genes were up-regulated expression under high temperature, oxidative stress, acid stress, and host serum stress. Particularly, among these usp genes, usp13, exhibited dramatically high expression level upon several stress conditions. To investigate the biological role of usp13, a markerless usp13 in-frame mutant strain, TX01Δusp13, was constructed. Compared to the wild type TX01, TX01Δusp13 exhibited markedly compromised tolerance to high temperature, hydrogen peroxide, and low pH. Deletion of usp13 significantly retarded bacterial biofilm growth and decreased resistance against serum killing. Pathogenicity analysis showed that the inactivation of usp13 significantly impaired the ability of E. piscicida to invade into host cell and infect host tissue. Introduction of a trans-expressed usp13 gene restored the lost virulence of TX01Δusp13. In support of these results, host immune response induced by TX01 and TX01Δusp13 was examined, and the results showed reactive oxygen species (ROS) levels in TX01Δusp13-infected macrophages were significantly higher than those in TX01-infected cells. The expression level of several cytokines (IL-6, IL-8, IL-10, TNF-α, and CC2) in TX01Δusp13-infected fish was significantly higher than that in TX01-infected fish. These results suggested that the deletion of usp13 attenuated the ability of bacteria to overcome the host immune response to pathogen infection. Taken together, our study indicated Usp13 of E. piscicida was not only important participant in adversity resistance, but also was essential for E. piscicida pathogenicity and contributed to block host immune response to pathogen infection.


Assuntos
Proteínas de Bactérias/genética , Ciclídeos/imunologia , Edwardsiella/imunologia , Edwardsiella/patogenicidade , Doenças dos Peixes/imunologia , Imunidade Inata/imunologia , Animais , Proteínas de Bactérias/imunologia , Edwardsiella/genética , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/veterinária , Filogenia , Virulência
12.
Water Environ Res ; 91(10): 1025-1033, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31243845

RESUMO

Wastewater in petrochemical processes and produced water from oil and gas production remain a challenge for the industry to minimize their impact on the environment. Recent research and development of treatment technologies for petrochemical wastewater and produced water from oil and gas industries published in 2018 were summarized in this annual review. Great efforts and progresses were made in various treatment options, including membrane processes, advanced oxidation, biological systems, adsorption, coagulation, and combined processes. PRACTITIONER POINTS: Treatment technologies for petrochemical wastewater are reviewed. Research development in produced water from oil and gas industries is summarized. Reviewed technologies include traditional, advanced, and innovative processes.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Indústrias , Oxirredução , Água
13.
Water Environ Res ; 90(10): 1899-1922, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30264688

RESUMO

The recent research and development on mine drainage published in 2017 was summarized in this review. In particular, this review was focused on three main aspects: 1) mine drainage and its environmental impact, 2) prediction and prevention, and 3) treatment technologies. The first section covers physiochemical characterization, microbiological characterization, and environmental impacts. The second section includes mine drainage prediction and prevention. The final section focuses physiochemical treatment, biological treatment, passive treatment, and beneficial uses of mine drainage and treatment wastes.


Assuntos
Resíduos Industriais , Mineração , Eliminação de Resíduos Líquidos/métodos
14.
Water Environ Res ; 89(10): 1384-1402, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28954666

RESUMO

This review summarizes the recent research and development pertaining to the topic of mine drainage which were published in 2016 and early 2017. The review includes three main sections: Mine Drainage and its Environmental Impact, Prediction and Prevention, and Treatment Technologies. The first section covers the characterization of mine drainage and its related environmental impacts, including three subsections focused on physiochemical characterization, microbiological characterization, and environmental impacts. The second section of the review is divided into two subsections focused on either the prediction or prevention of acid mine drainage. The final section focuses on treatment technologies for mine drainage, including physiochemical treatment, biological treatment, passive treatment, and beneficial uses of mine drainage and treatment wastes.


Assuntos
Resíduos Industriais/análise , Mineração/métodos , Poluentes Químicos da Água/análise , Resíduos Industriais/estatística & dados numéricos , Eliminação de Resíduos/métodos
15.
Water Environ Res ; 88(10): 1409-32, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27620096

RESUMO

This review provides a snapshot of papers published in 2015 relevant to the topic of mine drainage generation and control options. The review is broken into 3 sections: Generation, Prediction and Prevention, and Treatment Options. The first section, mine drainage generation, focuses on the characterization of mine drainage and the environmental impacts. As such, it is broken into three subsections focused on microbiological characterization, physiochemical characterization, and environmental impacts. The second section of the review is divided into two subsections focused on either the prediction or prevention of acid mine drainage. The final section focuses on treatment options for mine drainage and waste sludge. The third section contains subsections on passive treatment, biological treatment, physiochemical treatment, and a new subsection on beneficial uses for mine drainage and treatment wastes.


Assuntos
Resíduos Industriais/análise , Mineração , Eliminação de Resíduos/métodos , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Ácidos
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