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1.
N Engl J Med ; 389(9): 808-819, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37646678

RESUMO

BACKGROUND: Population screening of asymptomatic persons with Epstein-Barr virus (EBV) DNA or antibodies has improved the diagnosis of nasopharyngeal carcinoma and survival among affected persons. However, the positive predictive value of current screening strategies is unsatisfactory even in areas where nasopharyngeal carcinoma is endemic. METHODS: We designed a peptide library representing highly ranked B-cell epitopes of EBV coding sequences to identify novel serologic biomarkers for nasopharyngeal carcinoma. After a retrospective case-control study, the performance of the novel biomarker anti-BNLF2b total antibody (P85-Ab) was validated through a large-scale prospective screening program and compared with that of the standard two-antibody-based screening method (EBV nuclear antigen 1 [EBNA1]-IgA and EBV-specific viral capsid antigen [VCA]-IgA). RESULTS: P85-Ab was the most promising biomarker for nasopharyngeal carcinoma screening, with high sensitivity (94.4%; 95% confidence interval [CI], 86.4 to 97.8) and specificity (99.6%; 95% CI, 97.8 to 99.9) in the retrospective case-control study. Among the 24,852 eligible participants in the prospective cohort, 47 cases of nasopharyngeal carcinoma (38 at an early stage) were identified. P85-Ab showed higher sensitivity than the two-antibody method (97.9% vs. 72.3%; ratio, 1.4 [95% CI, 1.1 to 1.6]), higher specificity (98.3% vs. 97.0%; ratio, 1.01 [95% CI, 1.01 to 1.02]), and a higher positive predictive value (10.0% vs. 4.3%; ratio, 2.3 [95% CI, 1.8 to 2.8]). The combination of P85-Ab and the two-antibody method markedly increased the positive predictive value to 44.6% (95% CI, 33.8 to 55.9), with sensitivity of 70.2% (95% CI, 56.0 to 81.4). CONCLUSIONS: Our results suggest that P85-Ab is a promising novel biomarker for nasopharyngeal carcinoma screening, with higher sensitivity, specificity, and positive predictive value than the standard two-antibody method. (Funded by the National Key Research and Development Program of China and others; ClinicalTrials.gov number, NCT04085900.).


Assuntos
Anticorpos Antivirais , Detecção Precoce de Câncer , Herpesvirus Humano 4 , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Proteínas Virais , Humanos , Anticorpos Antivirais/imunologia , Estudos de Casos e Controles , Herpesvirus Humano 4/imunologia , Imunoglobulina A , Programas de Rastreamento , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/imunologia , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/imunologia , Neoplasias Nasofaríngeas/virologia , Estudos Prospectivos , Estudos Retrospectivos , Biomarcadores/análise , Proteínas Virais/imunologia , Epitopos/imunologia
2.
Environ Res ; 228: 115849, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37024030

RESUMO

The application of microbially induced carbonate precipitation (MICP) technology is critical, but many challenges remain. In this paper, a microbial fuel cell (MFC) is used to treat molasses wastewater, and the effluent is used as the substrate to promote the growth of urease-producing bacteria. The results showed that the maximum voltage of MFC was 500 mV, and the maximum power density was 169.86 mW/m2. The mineralization rate reached 100% on the 15th day, and the mineralized product was calcite CaCO3. According to the microbial community analysis, the unclassified_Comamondaceae, Arcobacter, and Aeromonas, which could improve the OH-, signal molecular transmission and small molecular nutrients to promote the urease activity of urease-producing bacteria. The above conclusions provide a new way to reuse molasses wastewater efficiently and to apply MICP technology in dust suppression.


Assuntos
Fontes de Energia Bioelétrica , Fontes de Energia Bioelétrica/microbiologia , Águas Residuárias , Melaço , Urease , Carbonatos , Bactérias
3.
Sensors (Basel) ; 23(10)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37430790

RESUMO

Due to the development of wireless network technology, various applications relying on good network quality are widely used on mobile devices. Taking the commonly used video streaming service as an example, a network with high throughput and low packet loss rate can meet the service requirements. When the moving distance of the mobile device is greater than the signal coverage of the AP, it will trigger the handover process to connect to another AP, and cause the network to disconnect and reconnect instantaneously. However, frequently triggering the handover procedure will cause a significant drop in network performance and affect the operation of application services. In order to solve this problem, this paper proposes the OHA and OHAQR. The OHA considers whether the signal quality is good or bad, and uses the corresponding HM method to solve the problem of frequent handover procedures. The OHAQR integrates the QoS requirements of the throughput and packet loss rate into the OHA with the Q-handover score, to provide high-performance handover services with QoS. Our experimental results show that the OHA and OHAQR have 13 and 15 handovers in a high-density scenario, respectively, and are better than the other two methods. The actual throughput and packet loss rate of the OHAQR are 123 Mbps and 5%, respectively, and the network performance is better than that of other methods. The proposed method shows excellent performance in ensuring the network QoS requirements and reducing the number of handover procedures.

4.
Environ Geochem Health ; 45(7): 4897-4913, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36988854

RESUMO

In order to solve the problem of environmental pollution caused by the escape of coal dust in open-pit coal mines, a composite dust suppressant was prepared from Enteromorpha, and the preparation factors (water-soluble polymer, temperature, solid content and surfactant) were optimized. The mechanism of dust suppression and the possibility of large-scale field application were discussed. The research results on the related properties of dust suppressants showed that the performance of Enteromorpha-based dust suppressants prepared by this method was excellent compared with similar studies. Among them, polyacrylamide (PAM) Enteromorpha-based dust suppressant had the best performance, with viscosity of 25.1 mPa s and surface tension of 27.05 mN/m. Moreover, PAM Enteromorpha-based dust suppressant had the best effect, with the mass loss of 2.94% under the wind speed of 10 m/s and the coal dust loss rate of 4.6% after rain erosion, and it had strong water retention performance. Through the discussion of dust suppression mechanism, it was found that the mechanical entangled network structure with hydrogen bonds as nodes was formed after the graft copolymerization of PAM and Enteromorpha. It had high permeability and good adhesion. After quickly wetting coal dust, it formed a dense package for coal dust. The field experiment also showed that the use of Enteromorpha-based dust suppressant can effectively inhibit the escape of coal dust. From the point of view of economy and efficiency, Enteromorpha can save 30% of the material cost and the dust suppression efficiency can reach 89-94%. Therefore, the Enteromorpha-based dust suppressant may stably suppress coal dust on the basis of reducing the cost.


Assuntos
Minas de Carvão , Poeira , Poeira/análise , Poluição Ambiental , Carvão Mineral/análise , Minerais , Água
5.
J Environ Manage ; 304: 114293, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34915385

RESUMO

Although composting techniques are continuously optimised and adjusted, the removal of bacterial pathogen based on the quality of composting products needs further to ensure safe of agricultural use. In this study, we combined aerobic composting and anaerobic process to determine the optimal combination (turning frequency of once a day, the proportion of swine manure to corn straw (3:1), and mixed 6-day anaerobic process) that benefits the reduction of bacterial pathogens, among which the maximum removal efficiency of up to 92.96% was observed for Clostridium_sensu_stricto_1 reached, thereby improving the quality of the compost products. The variation partition analysis and redundancy analysis indicated that physicochemical factors such as temperature, TOC, and pH significantly affected the removal of bacterial pathogens. Therefore, the additive effects of physicochemical factors on bacterial pathogen removal requires further process optimisation. These findings offer powerful technological support for improving agricultural waste recycling and enhancing the safety of fertiliser application.


Assuntos
Compostagem , Anaerobiose , Animais , Bactérias , Esterco , Solo , Suínos , Virulência
6.
Angew Chem Int Ed Engl ; 60(9): 4479-4484, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33230944

RESUMO

This work reports gold-catalyzed [3+2]-annulations of α-diazo ketones with highly substituted cyclopentadienes, affording bicyclic 2,3-dihydrofurans with high regio- and stereoselectivity. The reactions highlights the first success of tetrasubstituted alkenes to undergo [3+2]-annulations with α-diazo carbonyls. The enantioselective annulations are also achieved with high enantioselectivity using chiral forms of gold and phosphoric acid. Our mechanistic analysis supports that cyclopentadienes serve as nucleophiles to attack gold carbenes at the more substituted alkenes, yielding gold enolates that complex with chiral phosphoric acid to enhance the enantioselectivity.

7.
Clin Chem ; 66(1): 178-187, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31810998

RESUMO

BACKGROUND: Targeted next-generation sequencing is a powerful method to comprehensively identify biomarkers for cancer. Starting material is currently either DNA or RNA for different variations, but splitting to 2 assays is burdensome and sometimes unpractical, causing delay or complete lack of detection of critical events, in particular, potent and targetable fusion events. An assay that analyzes both templates in a streamlined process is eagerly needed. METHODS: We developed a single-tube, dual-template assay and an integrated bioinformatics pipeline for relevant variant calling. RNA was used for fusion detection, whereas DNA was used for single-nucleotide variations (SNVs) and insertion and deletions (indels). The reaction chemistry featured barcoded adaptor ligation, multiplexed linear amplification, and multiplexed PCR for noise reduction and novel fusion detection. An auxiliary quality control assay was also developed. RESULTS: In a 1000-sample lung tumor cohort, we identified all major SNV/indel hotspots and fusions, as well as MET exon 14 skipping and several novel or rare fusions. The occurrence frequencies were in line with previous reports and were verified by Sanger sequencing. One noteworthy fusion event was HLA-DRB1-MET that constituted the second intergenic MET fusion ever detected in lung cancer. CONCLUSIONS: This method should benefit not only a majority of patients carrying core actionable targets but also those with rare variations. Future extension of this assay to RNA expression and DNA copy number profiling of target genes such as programmed death-ligand 1 may provide additional biomarkers for immune checkpoint therapies.


Assuntos
Fusão Gênica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias Pulmonares/patologia , Variações do Número de Cópias de DNA , Éxons , Cadeias HLA-DRB1/genética , Humanos , Mutação INDEL , Modelos Lineares , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas c-met/genética
9.
Ecotoxicol Environ Saf ; 142: 207-215, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28411516

RESUMO

This study was conducted to investigate the possibility of using a combined technology to synchronously reduce As and Cd accumulation in the edible parts of Brassica campestris. The results showed that a foliar application of selenite (Se) and silicon (Si) combined with soil ameliorants (including Ca-Mg-P fertilizer, sodium silicate and red mud) showed limited effects on the growth of B. campestris. The As concentration in the leaves of B. campestris in all treatments was below the Chinese safety standard. When sodium silicate and Ca-Mg-P fertilizer were added to the soil, the additional foliar application of Se and Si could in some cases help further reduce the concentrations of As and Cd in the leaves of B. campestris. However, when red mud was applied to the soil, the foliar application of Se and Si enhanced the Cd concentration in the leaves of B. campestris. In most cases, high levels of soil ameliorants plus foliar application of Se and Si significantly enhanced the As concentrations in both the soil solution and the roots of B. campestris but reduced the soil solution Cd concentration and the leaf As concentration. Most of the treatments reduced the thiobarbituric acid reactive substances (TBARS) concentration in the leaves of B. campestris, and the foliar application of Se and Si helped the soil ameliorants alleviate the oxidative stress resulting from As and Cd exposure. In this study, several treatments significantly increased the activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX). However, the enzymes peroxidase (POD) and catalase (CAT) were not induced by most treatments. In summary, the combined treatment of 1gkg-1 Ca-Mg-P fertilizer plus foliar spraying 2mmolL-1 sodium selenite was most effective in reducing the Cd concentration and a rather strong ability to reduce the As concentration and trigger the activities of SOD and APX in the leaves of B. campestris.


Assuntos
Antioxidantes/metabolismo , Arsenicais/análise , Brassica/metabolismo , Cádmio/análise , Fertilizantes/análise , Ácido Selenioso/farmacologia , Silicatos/farmacologia , Poluentes do Solo/análise , Arsenicais/metabolismo , Ascorbato Peroxidases/metabolismo , Brassica/química , Brassica/efeitos dos fármacos , Brassica/crescimento & desenvolvimento , Cádmio/metabolismo , Catalase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peroxidases/metabolismo , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Solo/química , Solo/normas , Poluentes do Solo/metabolismo , Superóxido Dismutase/metabolismo
10.
Plant Mol Biol ; 89(4-5): 385-401, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26350403

RESUMO

Although the main genes in rice involved in the biosynthesis of secondary wall components have been characterized, the molecular mechanism underlying coordinated regulation of genes expression is not clear. In this study, we reported a new rice variety, cef1, showed the culm easily fragile (CEF) without other concomitant phenotypes. The CEF1 gene encodes a MYB family transcription factor OsMYB103L, was cloned based on map-based approach. Bioinformatics analyses indicated that CEF1 belongs to the R2R3-MYB subfamily and highly similar to Arabidopsis AtMYB103. Expression pattern analysis indicated that CEF1 is mainly expressed in internodes and panicles. Biochemical assays demonstrated that OsMYB103L is a nuclear protein and shows high transcriptional activation activity at C-terminus. OsMYB103L mediates cellulose biosynthesis and secondary walls formation mainly through directly binding the CESA4, CESA7, CESA9 and BC1 promoters and regulating their expression. OsMYB103L may also function as a master switch to regulate the expression of several downstream TFs, which involved in secondary cell wall biosynthesis. Furthermore, OsMYB103L physically interacts with SLENDER RICE1 (SLR1), a DELLA repressor of GA signaling, and involved in GA-mediated regulation of cellulose synthesis pathway. Our findings revealed that OsMYB103L plays an important role in GA-regulating secondary cell wall synthesis, and the manipulation of this gene provide a new strategy to help the straw decay in soil.


Assuntos
Parede Celular/metabolismo , Genes de Plantas , Giberelinas/metabolismo , Oryza/genética , Oryza/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Celulose/biossíntese , Mapeamento Cromossômico , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Fenótipo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Fatores de Transcrição/química , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Técnicas do Sistema de Duplo-Híbrido
11.
Int J Cancer ; 136(5): E301-12, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25213622

RESUMO

More than 75% of nasopharyngeal carcinoma (NPC) patients have already developed local or regional spread at diagnosis, which hampers effective treatment and results in a poor prognosis. It is essential to characterize more sensitive and specific biomarkers for screening of high risk individuals and assessment of NPC treatment effectiveness. NPC is an Epstein-Barr virus (EBV) associated tumor in which only a few viral proteins but more than 20 BamHI A rightward transcripts (BART) microRNAs are detected, at abundant levels. We hypothesized that these BART microRNAs may be novel biomarkers for NPC. Systematic analysis of EBV BART microRNA expression profiles in EBV latently infected Mutu I and Mutu III cell lines, EBV-harboring NPC and noncancerous NP cells found that miR-BART3, miR-BART7 and miR-BART13 microRNAs are highly expressed and regularly secreted into the extracellular environment of NPC cells. These BART microRNAs were evaluated for used as potential NPC biomarkers. Analysis of plasma specimens obtained from NPC patients (n = 89), and healthy (n = 28) and non-NPC tumor patient controls (n = 18) found levels of both miR-BART7 and miR-BART13, but not miR-BART3, to be distinctly presence among NPC patients, with elevated levels being particularly apparent among patients with advanced disease. Receiver operating characteristic curve analysis combining miR-BART7 and miR-BART13 levels produces a 90% predictive value for the presence of NPC. Analysis of 41 NPC patients before and after radiotherapy showed that miR-BART7 and miR-BART13, but not miR-BART3, were diminished after treatment. These results indicate that EBV microRNAs, miR-BART7 and miR-BART13, may constitute useful new serological biomarkers for diagnosis of NPC and prediction of treatment efficacy.


Assuntos
Infecções por Vírus Epstein-Barr/genética , Regulação Neoplásica da Expressão Gênica , Herpesvirus Humano 4/genética , MicroRNAs/sangue , MicroRNAs/genética , Neoplasias Nasofaríngeas/genética , Recidiva Local de Neoplasia/genética , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Carcinoma , Quimiorradioterapia , Infecções por Vírus Epstein-Barr/sangue , Infecções por Vírus Epstein-Barr/terapia , Infecções por Vírus Epstein-Barr/virologia , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/sangue , Neoplasias Nasofaríngeas/terapia , Neoplasias Nasofaríngeas/virologia , Invasividade Neoplásica , Recidiva Local de Neoplasia/terapia , Recidiva Local de Neoplasia/virologia , Estadiamento de Neoplasias , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carga Viral , Adulto Jovem
12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(1): 292-296, 2024 Feb.
Artigo em Zh | MEDLINE | ID: mdl-38387937

RESUMO

PI3K/AKT/mTOR signaling pathway is of great significance in the development and prognosis of tumors, and is closely related to the pathogenesis of multiple myeloma (MM). PI3K/AKT/mTOR signaling pathway can participate in the regulation of MM through multichannel and multitarget, such as regulating the tumor microenvironment of MM cells survival, affecting tumor development and migration, regulating the proliferation, apoptosis and autophagy of MM cells. It have shown that after the PI3K/AKT/mTOR signaling pathway is inhibited, the apoptosis and autophagy of MM cells are activated, which promote the death of MM cells and inhibit the metastasis and recurrence of MM cells. Therefore, indepth study of the mechanism of PI3K/AKT/mTOR signaling pathway in MM is helpful to elucidate the pathogenesis and prognosis of MM.


Assuntos
Mieloma Múltiplo , Proteínas Proto-Oncogênicas c-akt , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proliferação de Células , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Apoptose , Autofagia/fisiologia , Linhagem Celular Tumoral , Microambiente Tumoral
13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(1): 318-321, 2024 Feb.
Artigo em Zh | MEDLINE | ID: mdl-38387942

RESUMO

Multiple myeloma (MM) is a malignant disease with abnormal proliferation of clonal plasma cells. The development of the disease shows a vast heterogeneity, which is closely related to the interaction between MM cells and bone marrow microenvironment (BMM). The interleukin-6 (IL-6)/interleukin-6 receptor (IL-6R)/Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway can regulate the transcription of related soluble factors in BMM, promote the proliferation, anti-apoptosis, drug resistance and guide related bone destruction of MM cells. This article reviews the research progress on the effect of BMM regulated by IL-6/IL-6R/JAK2/STAT3 pathway on the biological behavior of MM, in order to provide new research ideas for targeted therapy and precise therapy of MM.


Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/tratamento farmacológico , Interleucina-6/metabolismo , Janus Quinase 2 , Medula Óssea/metabolismo , Fator de Transcrição STAT3/metabolismo , Receptores de Interleucina-6/metabolismo , Microambiente Tumoral
14.
Am J Epidemiol ; 177(3): 242-50, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23255783

RESUMO

A nasopharyngeal carcinoma (NPC) mass screening trial using a combination of immunoglobulin A antibodies to Epstein-Barr virus capsid antigen and nuclear antigen-1 by enzyme-linked immunosorbent assay in addition to indirect mirror examination in the nasopharynx and/or lymphatic palpation (IMLP) was conducted in southern China. Cantonese aged 30-59 years residing in 2 cities randomly selected by cluster sampling, Sihui and Zhongshan, were invited to participate in this screening from May 2008 through May 2010. Participants were offered fiberoptic endoscopy examination and/or pathologic biopsy if their serologic tests reached our predefined level of high risk or if results from the physical examination indicated possible cancer (i.e., were IMLP positive). A total of 28,688 individuals were voluntarily screened in the initial round. The overall NPC detection rate was 0.14% (41/28,688) with an early diagnosis rate of 68.3% (28/41) during the first year of follow-up. Thirty-eight of 41 cases (92.7%) were detected among the high-risk group, and 7 of 41 cases (17.1%) were detected among the IMLP-positive group. The 2 Epstein-Barr virus serologic tests by enzyme-linked immunosorbent assay could be a feasible alternative for NPC screening in endemic areas. Further follow-up is needed to examine whether screening has an effect on decreasing mortality from NPC in these areas.


Assuntos
Anticorpos Antivirais , Antígenos Virais , Proteínas do Capsídeo , Detecção Precoce de Câncer/métodos , Neoplasias Nasofaríngeas/diagnóstico , Adulto , Carcinoma , China/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo
15.
Int J Biol Macromol ; 231: 123287, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36652985

RESUMO

Traditional polymer dust suppressants are limited due to environmental pollution, while polymer gels have attracted attention due to the advantages of environmental protection and good biocompatibility. The purpose of this research is to prepare a new type of dust suppressant with a gel network structure, which was synthesized from soybean protein isolate and glycosylated with xanthan gum. The experimental results showed that the product obtained by reacting 0.2 % xanthan gum and 0.1 % soybean protein isolate at 90 °C for 4 h has the best binding effect on coal dust, and the coal husk hardness can reach 83 HA. The microscopic reaction and structure of the product were analyzed by infrared spectroscopy, X-ray diffractometer, and scanning electron microscope, and the results revealed the structural change and specific reaction process of the product. In addition, through molecular dynamics simulation, the dust suppression effect was confirmed and the mechanism of action between dust suppressant and coal was revealed. The performance test of the dust suppressant showed that its viscosity is 23.4 mPa·s, the contact angle at 1 s is 10.01°, the PM10 dust suppression efficiency can reach 98.10 %, the water retention is 44.44 % higher than that of water, and thermal stability is improved.


Assuntos
Poeira , Polímeros , Poeira/análise , Proteínas de Soja , Carvão Mineral/análise , Géis , Água
16.
Environ Sci Pollut Res Int ; 30(21): 60129-60149, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37017838

RESUMO

The dust pollution at the fully mechanized heading face has seriously threatened the health of the miners. As the main technical means, the outer spray of a roadheader has the problems of small coverage of the fog field and low dust removal efficiency. Based on the multiscale swirl atomization model of LES-VOF, this study simulated and analyzed the atomization process of the nozzle. The influence law of the diameter, the length and the circulation area ratio of the swirl chamber, and the swirl core angle on the swirl number and atomization effect were determined, and the nonlinear function relationship between variables was obtained. With the help of the BP neural network model, a new type of swirl nozzle is developed which is suitable for the outside spray system at the fully mechanized heading face. The experimental results show that the error between the predicted results of the new swirl nozzle and BP network model is less than 15%, the atomization angle θc is 24.2°, the average particle size D32 is 64.43 µm, and the effective range Reff is about 2.1 m. At the same time, the total dust removal efficiency and respirable dust removal efficiency of the new swirl nozzle at the driver's place are 61.10% and 63.85%, respectively, which are 21.69% and 20.92% higher than the original nozzle.


Assuntos
Poeira , Poluição Ambiental , Tamanho da Partícula
17.
ACS Omega ; 8(43): 40153-40161, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37929149

RESUMO

During deep underground coal gasification, the semicoke produced by the pyrolysis of dense coal cores is an important material for its gasification and combustion. In this paper, pressurized pyrolysis experiments were carried out on dense coal cores at 700 °C and pressures of 1, 2, and 3 MPa using a shaft furnace. The resulting semicoke and raw coal were analyzed using the characterization methods such as the N2 isothermal adsorption/desorption and scanning electron microscopy, Fourier transform infrared spectrometry (FTIR), and a pressurized thermogravimetric analyzer coupled with a FTIR spectrometer. The pyrolysis gas generation characteristics during pressurized pyrolysis were studied. The mechanisms of evolution of aliphatic functional groups and pore structures in semicoke during pressurized pyrolysis were revealed. The results indicate that the increase in pressure obviously changed the gas composition, most notably, the relative content of CH4 and H2 in the pyrolysis gas. The methane in the pyrolysis gas during pressurized pyrolysis of dense coal cores is mainly from the secondary reaction. As the pyrolysis pressure increased, the ratio of -CH2-/-CH3 became smaller, indicating that the pressure promoted the breakage of the long fat chains. With the increase of the pyrolysis pressure, the surface deformation of pressurized pyrolysis semicoke increases, and the pore structure becomes more abundant.

18.
Environ Sci Pollut Res Int ; 30(55): 117225-117237, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37864697

RESUMO

Carbon dioxide mineral carbonisation is a means to achieve permanent carbon dioxide storage, this paper to solid waste materials as the main raw material to prepare fly ash-based carbon dioxide storage materials. Through the design of carbon dioxide adsorption experimental setup to study the main factors affecting the adsorption capacity of the fly ash-based storage materials, the experimental results show that, the fly ash mass fraction decreased from 90 to 10%, the water-cement ratio increased from 0.4 to 0.8 when the CO2 adsorption of fly ash-based materials increased by 82% and 30%, respectively. The effect of strong alkali on CO2 adsorption capacity was also investigated in this paper, and the results showed that the CO2 adsorption of the fly ash-based material sample with 10 ml NaOH added increased by 197% compared with that of the sample with 5 ml NaOH added, whereas the adsorption amount was reduced by 85% when 25 ml NaOH was added instead, which was attributed to the accelerated hydration process of the material due to the excessive alkalinity that consumed the calcium and magnesium ions in the material, and at the same time the production of hydration products hindered the transport of CO2 within the material, which led to a decrease in CO2 adsorption.


Assuntos
Dióxido de Carbono , Cinza de Carvão , Adsorção , Sequestro de Carbono , Hidróxido de Sódio
19.
Environ Sci Pollut Res Int ; 30(1): 18-35, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36371569

RESUMO

Coal mine pollution is a serious threat to the mine safe production and occupational health of miners. Chemical dust suppression can effectively reduce the concentration of coal dust and suppress the re-entrainment of dust. This paper discusses the research progress of three kinds of traditional dust suppressants: the wetting-type, cohesive type, and condensed type. In order to meet dust suppression and environmental protection requirements, 7 kinds of new type dust suppressants, such as compound, ecological environmental protection, polymer, functional, microbes, and enzymes, have been developed by the predecessors. And all kinds of dust suppressant mechanism and main performance index have been summarized. Through the analysis of the research results from 1985 to 2021, it is found that the compound and environment-friendly dust suppressants have gradually become the research focus in this field, accounting for 17.93% and 26.21% of the total number of achievements. In the recent 5 years, new materials, such as microbe suppressant, urease suppressant, and nanomaterials, have gradually emerged. Because of their natural and environmental protection characteristics, it could be predicted that they will become the future development trend in this field. However, there are still some problems to be improved, such as expensive price and complex preparation technology.


Assuntos
Minas de Carvão , Mineradores , Exposição Ocupacional , Humanos , Poeira/análise , Minerais , Carvão Mineral/análise
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 123007, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37393670

RESUMO

Chemical oxygen demand (COD), ammonia nitrogen (AN) and total nitrogen (TN) are the key parameters to reflect the degree of surface water pollution. Ultraviolet - visible (UV-Vis) spectroscopy and near - infrared (NIR) spectroscopy are ideal techniques for rapid monitoring of these indicators. In this study, a strategy based on the fusion of UV-Vis and NIR spectral data (UV-Vis-NIR) for water quality detection was proposed to further improve the quantitative analysis accuracy of spectroscopic methods. Seventy river samples with different levels of pollution were used for spectroscopic analysis. The UV-Vis-NIR fusion spectrum of each water sample was obtained by directly splicing sample's UV-Vis spectrum and NIR diffuse transmission spectrum. The UV-Vis-NIR fusion models were optimized through using different variable selection algorithms. The results show that the UV-Vis-NIR fusion models for surface water COD, AN and TN achieves better prediction results (the root mean square errors of prediction are 6.95, 0.195, and 0.466, respectively) than single-spectroscopic based models. Since better prediction performances were shown under different optimization conditions, the robustness of fusion models were also better than the single-spectroscopic based models. Therefore, the data fusion strategy proposed in this study has a promising application prospect for further accurate and rapid monitoring of surface water quality.

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