Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 59
Filtrar
1.
Entropy (Basel) ; 24(8)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36010788

RESUMO

Accurate and fine-grained prediction of PM2.5 concentration is of great significance for air quality control and human physical and mental health. Traditional approaches, such as time series, recurrent neural networks (RNNs) or graph convolutional networks (GCNs), cannot effectively integrate spatial-temporal and meteorological factors and manage dynamic edge relationships among scattered monitoring stations. In this paper, a spatial-temporal causal convolution network framework, ST-CCN-PM2.5, is proposed. Both the spatial effects of multi-source air pollutants and meteorological factors are considered via spatial attention mechanism. Time-dependent features in causal convolution networks are extracted by stacked dilated convolution and time attention. All the hyper-parameters in ST-CCN-PM2.5 are tuned by Bayesian optimization. Haikou air monitoring station data are employed with a series of baselines (AR, MA, ARMA, ANN, SVR, GRU, LSTM and ST-GCN). Final results include the following points: (1) For a single station, the RMSE, MAE and R2 values of ST-CCN-PM2.5 decreased by 27.05%, 10.38% and 3.56% on average, respectively. (2) For all stations, ST-CCN-PM2.5 achieve the best performance in win-tie-loss experiments. The numbers of winning stations are 68, 63, and 64 out of 95 stations in RMSE (MSE), MAE, and R2, respectively. In addition, the mean MSE, RMSE and MAE of ST-CCN-PM2.5 are 4.94, 2.17 and 1.31, respectively, and the R2 value is 0.92. (3) Shapley analysis shows wind speed is the most influencing factor in fine-grained PM2.5 concentration prediction. The effects of CO and temperature on PM2.5 prediction are moderately significant. Friedman test under different resampling further confirms the advantage of ST-CCN-PM2.5. The ST-CCN-PM2.5 provides a promising direction for fine-grained PM2.5 prediction.

2.
Anal Chem ; 92(7): 5411-5418, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32207293

RESUMO

Accurate identification of exosomes plays an essential role in facilitating disease diagnosis and therapies. Herein, we proposed an Aptamer-cholesterol-mediated Proximity Ligation Assay (AcmPLA) for accurate identification of exosomes in a dual-probe strategy, one aptamer probe for recognition of exosomal innate surface protein CD63 and another cholesterol probe for biolipid layer targeting. By integrating a proximity ligation of probes bound with exosomal biomarkers for specific recognition and a rolling circle amplification (RCA) strategy for signal amplification, we have successfully developed an exosomes-surface approach that can perform "AND" logic analysis of dual biomarkers, which not only could be used for exosomes quantification, but also for exosomes tracing. Besides RCA-initiated signal amplification, CD9 antibody-labeled magnetic beads were used to capture exosomes for isolation and secondary signal enrichment. Our approach can achieve specific exosomes isolation and accurate identification and thus could be exploited for broad applications in biological science, biomedical engineering, and personalized medicine.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , Técnicas Biossensoriais/métodos , Colesterol/metabolismo , Exossomos/metabolismo , Células A549 , Humanos , Limite de Detecção , Sondas Moleculares/metabolismo
3.
Anal Bioanal Chem ; 412(3): 601-609, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31897558

RESUMO

Numerous studies have shown that exosomes are closely related to the pathogenesis of various diseases, especially cancers. Therefore, a rapid and sensitive method for exosome detection will be of great importance for the diagnosis and prognosis of diseases. We report here a method for exosome detection based on the CD63 aptamer and clustered regular interspaced short palindromic repeats (CRISPR)/Cas12a system. This method consists mainly of exosomal membrane protein recognition based on the CD63 aptamer and signal amplification based on CRISPR/Cas12a. The CD63 aptamer, as an easily adaptable nucleic acid strand, is responsible for the conversion of the amounts of exosomes into nucleic acid detection, whereas CRISPR/Cas12a is responsible for highly specific nucleic acid signal amplification. The detection range of the method was determined as 3 × 103-6 × 107 particles per microliter. Additionally, we successfully applied this method to detect exosomes in clinical samples from both healthy individuals and patients with lung cancer, and the results were highly consistent with those obtained by nanoparticle tracking analysis. In general, this method provides a highly sensitive and specific method for the detection of exosomes and offers an avenue toward future exosome-based diagnosis of diseases.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Exossomos/química , Tetraspanina 30/análise , Células A549 , Sistemas CRISPR-Cas , Exossomos/patologia , Humanos , Neoplasias Pulmonares/patologia , Técnicas de Amplificação de Ácido Nucleico/métodos
4.
Environ Sci Technol ; 52(7): 4313-4323, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29518313

RESUMO

Enhancing activated sludge dewaterability is of scientific and engineering importance in the face of accelerated urbanization and stringent environmental regulations. In this study, we investigated the integration of acidification and ultrasound (A/US) treatment for improving sludge dewaterability at both bench- and pilot-scales. Our results showed that the A/US process exhibited significantly improved sludge dewatering performance, characterized by capillary suction time, cake moisture, and water/solid content of sludge cake. Synergistic dewatering mechanisms were elucidated with a suite of macro and spectroscopic evidence. Characterization of treated sludge revealed that US-induced thermal, mechanical shearing force, and radical oxidation effects disrupts floc cells and accelerates the decomposition of extracellular polymeric substances (EPS), releasing bound water into the bulk phase. In addition to enhancing hydrolysis of EPS, the acidic pH environment caused the protonation of functional groups on EPS, facilitating the reflocculation of US decomposed sludge for improved filterability. Our bench-scale and pilot-scale investigations provide a mechanistic basis for better understanding of the A/US process, and enable development of a viable and economical dewatering technology.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Concentração de Íons de Hidrogênio , Oxirredução , Água
5.
J Sep Sci ; 39(12): 2396-405, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27121535

RESUMO

A new facile, rapid, inexpensive, and sensitive method for the analysis of six trace trichlorophenols in seawater samples was developed by magnetic micro-solid-phase extraction coupled to liquid chromatography with tandem mass spectrometry. Core-shell covalently functionalized ferroferric oxide coated with aminated silicon dioxide and decorated with multiwalled carbon nanotubes was applied as an adsorbent to perform the extraction process. The effect of factors including solution pH, contact time, adsorbent amount, and ionic strength were investigated in detail. The obtained results revealed that the proposed adsorbent was a highly effective and low-cost magnetic micro-solid-phase extraction material for the enrichment of 2,3,4-trichlorophenol, 2,3,5-trichlorophenol, 2,3,6-trichlorophenol, 2,4,5-trichlorophenol, 2,4,6-trichlorophenol, and 3,4,5-trichlorophenol from seawater. Under the optimized conditions, the recoveries ranged from 88.0 to 99.5% at the three spiking levels, the limits of detection and the limits of quantification were 0.002 and 0.007 µg/L for the six trichlorophenols, respectively. The intra- and interday relative standard deviations were 2.0-6.7 and 4.5-8.9%, respectively. The calibration curves showed a good linearity in the range of 0.02-5.0 µg/L. The routine run analyses showed that the developed method was fast, simple, accurate, solvent-saving and high resolution, and it was suitable for the determination of trace trichlorophenols in seawater.

6.
Cancer Sci ; 105(7): 755-62, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24815002

RESUMO

Osteosarcoma typically arises in tissues of mesenchymal origin, and is the most malignant bone tumor characterized by high local aggressiveness, with poor therapeutic outcome. Busulfan has been widely used to treat CML. So far, there are no reports on the therapeutic effect of busulfan on osteosarcoma. Here, we showed that busulfan dose-dependently reduced the cell viability and proliferation, and induced cell apoptosis, senescence, and reactive oxygen species levels in two osteosarcoma cell lines. Moreover, a series of loss-of-function and gain-of-function experiments further indicated that busulfan may have its anti-osteosarcoma effect by upregulating the microRNA-200 (miR-200) family which subsequently downregulated its target genes ZEB1 and ZEB2. Furthermore, treatment with busulfan potentially inhibited the growth of implanted osteosarcoma in nude mice. Taken together, our data suggest that busulfan may have an anti-osteosarcoma effect through downregulating ZEB1 and ZEB2 through activating the miR-200 family, highlighting a possibility of using busulfan as a novel therapy for osteosarcoma.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , Bussulfano/farmacologia , MicroRNAs/genética , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , Animais , Antineoplásicos Alquilantes/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Masculino , Camundongos , Camundongos Nus , Osteossarcoma/patologia , Espécies Reativas de Oxigênio/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Homeobox 2 de Ligação a E-box com Dedos de Zinco , Homeobox 1 de Ligação a E-box em Dedo de Zinco
7.
Proc Natl Acad Sci U S A ; 108(15): 6004-7, 2011 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-21444785

RESUMO

The behavior of volatiles is crucial for understanding the evolution of the Earth's interior, hydrosphere, and atmosphere. Noble gases as neutral species can serve as probes and be used for examining gas solubility in silicate melts and structural responses to any gas inclusion. Here, we report experimental results that reveal a strong effect of helium on the intermediate range structural order of SiO(2) glass and an unusually rigid behavior of the glass. The structure factor data show that the first sharp diffraction peak position of SiO(2) glass in helium medium remains essentially the same under pressures up to 18.6 GPa, suggesting that helium may have entered in the voids in SiO(2) glass under pressure. The dissolved helium makes the SiO(2) glass much less compressible at high pressures. GeO(2) glass and SiO(2) glass with H(2) as pressure medium do not display this effect. These observations suggest that the effect of helium on the structure and compression of SiO(2) glass is unique.

8.
Water Sci Technol ; 70(7): 1285-91, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25325555

RESUMO

Aimed at cost saving and pollution reduction, a novel desulfurization wastewater evaporation treatment system (DWETS) for handling wet flue gas desulfurization (WFGD) wastewater of a coal-fired power plant was studied. The system's advantages include simple process, and less investment and space. The feasibility of this system has been proven and the appropriate position and number of nozzles, the spray droplet size and flue gas temperature limitation have been obtained by computational fluid dynamics (CFD) simulation. The simulation results show that a longer duct, smaller diameter and higher flue gas temperature could help to increase the evaporation rate. The optimal DWETS design of Shangdu plant is 100 µm droplet sprayed by two nozzles located at the long duct when the flue gas temperature is 130 °C. Field tests were carried out based on the simulation results. The effects of running DWETS on the downstream devices have been studied. The results show that DWETS has a positive impact on ash removal efficiency and does not have any negative impact on the electrostatic precipitator (ESP), flue gas heat exchanger and WFGD. The pH values of the slurry of WFGD slightly increase when the DWETS is running. The simulation and field test of the DWETS show that it is a feasible future technology for desulfurization wastewater treatment.

9.
Heliyon ; 10(5): e26471, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38439891

RESUMO

The purpose of this study is to expand and deepen research in the field of safety production, explore the role of enterprises as decision-making entities in safety production, analyze the role of different types of decision-making behaviors in the process of enterprise safety production, and provide certain theoretical guidance for multi-agent decision-making in safety production. By summarizing and comparing the existing dual system of supply chain safety management, this study proposes dividing supply chain safety management into the two categories of safety organization and safety research and development (safety R&D) in the context of digitalization. Differential equations are established to describe a two-level supply chain safety management problem including manufacturers and suppliers. The research results show that, compared with the Nash equilibrium, when there are strong manufacturers involved in safety management cooperation, the manufacturer's safety R&D subsidy to suppliers improves the total revenue of the supply chain. When the manufacturer's safety organization supervision efficiency is high, the Stackelberg equilibrium is lower. It is a Pareto improvement for the manufacturer to supervise the supplier's safety organization to the Nash equilibrium. In the case of dual safety cooperation in the supply chain, when there are strong manufacturers, R&D subsidies have a crowding out effect on the safety organization cooperation. Finally, based on the example analysis, relevant suggestions are put forward for supply chain safety management.

10.
ACS Omega ; 9(13): 15350-15356, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38585076

RESUMO

Signal amplification strategies have emerged as a prominent tool in the field of improving the detection sensitivity of small extracellular vesicles (sEVs). It is important to highlight that the utilization of signal quenching strategies is not commonly implemented. A detection technique for sEVs was established based on the unwinding of G-quadruplex using Klenow fragment polymerase (KF), which served as an inspiration for this study. This system is characterized by its simplicity and lack of labeling, making it an efficient approach for signal quenching. In the presence of sEVs, the CD63 aptamer in the capture@sMBs complex binds with the CD63 protein on the surface of sEVs to release trigger sequences, which were employed as a primer to mediate the DNA polymerase/endonuclease-assisted signal recycling. The signal recycling process produces numerous single-stranded DNA sequences that can bind to the toehold section of the G-quadruplex. This leads to the rupture of the G-quadruplex structure and the subsequent deactivation of a DNAzyme generated by the G-quadruplex structure and hemin, thereby inhibiting its biological catalytic function. Consequently, the G-quadruplex structure would undergo a transformation to a duplex structure, leading to the emergence of a discernible differential signal that can be noticed in a majority of instances, even without the aid of magnification devices. The decrease in the prominent signal allows for the efficient analysis of target sEVs, which exhibit a notably low detection limit. In addition to the detection of sEVs, the approach has also been utilized for the investigation of miRNA-21. The approach demonstrates a high level of selectivity and robustness in its capacity to differentiate between target miRNA and base-mismatched miRNA as well as other miRNA families. This statement suggests that the assay holds significant promise for use in biochemical research and clinical diagnosis.

11.
Macromol Rapid Commun ; 34(14): 1163-8, 2013 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-23740833

RESUMO

The synthesis, characterization, and photophysical and photovoltaic properties of two anthracene-containing wide-band-gap donor and acceptor (D-A) alternating conjugated polymers (P1 and P2) are described. These two polymers absorb in the range of 300-600 nm with a band gap of about 2.12 eV. Polymer solar cells with P1:PC71 BM as the active layer demonstrate a power conversion efficiency (PCE) of 2.23% with a high Voc of 0.96 V, a Jsc of 4.4 mA cm(-2) , and a comparable fill factor (FF) of 0.53 under simulated solar illumination of AM 1.5 G (100 mW cm(-2) ). In addition, P2:PC71 BM blend-based solar cells exhibit a PCE of 1.42% with a comparable Voc of 0.89 V, a Jsc of 3.0 mA cm(-2) , and an FF of 0.53.


Assuntos
Antracenos/química , Polímeros/síntese química , Quinoxalinas/química , Energia Solar , Tiadiazóis/química , Técnicas Eletroquímicas , Estrutura Molecular , Solubilidade , Luz Solar
12.
Heliyon ; 9(10): e20494, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37810846

RESUMO

The disclosure of work safety information of listed companies in high-risk industries is an important aspect of their social responsibility, and it is also an inevitable requirement to meet the right of stakeholders to know, which has a far-reaching impact on the development of enterprises. In order to clarify the impact mechanism of work safety information disclosure on enterprise performance of listed companies in high-risk industries. 222 listed companies in high-risk industries were taken as the research object, and the multiple regression analysis method was used to analyze the relationship between the level of work safety information disclosure of enterprises and their financial performance, safety performance and social reputation. The results show that the work safety information disclosure of listed companies in high-risk industries has a positive impact on corporate financial performance, safety performance and social reputation; unabsorbed slack resources have a positive U-shaped regulatory effect on work safety information disclosure and enterprise social reputation; The shareholding ratio of institutional investors has an inverted U-shaped regulatory effect on the positive relationship between work safety information disclosure and enterprise social reputation. This study has enriched the theoretical and practical exploration of research on work safety information disclosure. It can help improve the level of work safety information disclosure and safety management in enterprises, while guiding the sustainable development of occupational health and safety within these organizations.

13.
Heliyon ; 9(6): e16717, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37484320

RESUMO

Industrial parks make great contributions to the local economy, society, and culture, but they have also encountered many problems, such as limited resources, the longevity of ecological restoration, and the contagion of safety accidents. As a socioeconomic and ecological composite system formed by the interaction of multiple stakeholders, the solutions to succeed in workplace sustainability in industrial parks are still not known. The purpose of this study is to explore how to integrate existing resources to achieve a win-win situation in industrial park safety and environmental protection issues. According to Actor-network Theory and a systematic search, this study identifies the relevant subjects from selected 24 studies and clarifies the interactions made by these subjects. In sum, this study concludes two main modes of developing workplace sustainability in the park from multiple actors' perspectives: self-regulation of inner park subjects and the driving force of exterior park subjects.

14.
Environ Sci Pollut Res Int ; 30(27): 71103-71119, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37160512

RESUMO

As Chi na's shipping industry continues to develop, ship emissions have become a significant source of pollutants. Consequently, it has become imperative to comprehend accurately the nature and attributes of ship pollutant emissions and understand their causation and effect as a crucial aspect of pollution control and legislation. This paper employs high-precision automatic identification system (AIS) dynamic and static data, along with pollutant emission parameters, to estimate the pollutant emissions from a ship's main engine, auxiliary engine, and boiler using a dynamic approach. Additionally, the study considers the sailing state and trajectory of the vessel and analyzes the characteristics of ship carbon emissions. Taking Tianjin Port as an example, this study conducts a multi-dimensional analysis of pollutant emissions to gain insight into the causation and effect of pollutants based on the collected big AIS data. The results show that the pollutant emissions in this region are mainly concentrated in the vicinity of Tianjin Port land port area, Dagusha Channel, and the Main Shipping Channel of Tianjin Xingang Fairway. Carbon emissions peak in September and are lower in June and December. Through accurate analysis of pollutant emission sources and emission characteristics in the region, this paper establishes the regular relationship between pollutant emissions and possible influencing factors and provides data support for China to formulate accurate pollutant emission reduction policies and regulate ship construction technology and carbon trading.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Poluentes Atmosféricos/análise , Navios , Emissões de Veículos/análise , Big Data , Monitoramento Ambiental/métodos
15.
Math Biosci Eng ; 20(4): 7316-7348, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-37161154

RESUMO

Based on the Protection Motivation Theory (PMT), the Psychological Reactance Theory (PRT), and the Theory of Planned Behavior (TPB), we revealed the psychological impact factors of individuals' private car purchase intentions during the new normal of COVID-19. Structural equation modeling (SEM) and Bayesian network (BN) were used to analyzed the car purchase decision-making mechanism. A questionnaire survey was conducted to collect empirical data from April 20th to May 26th of 2020 in China. We investigated 645 participants and analyzed the data. The SEM results showed that conditional value, pro-car-purchasing attitude, and perceived behavioral control, health value, and cost factors have significant direct effects on car purchase intention. According to BN's prediction of purchase intention, the probability of high purchase intention grew by 47.6%, 97.3% and 163.0%, respectively, with perceived behavioral control, pro-car-purchasing attitude, and conditional value shifting from "low" to "medium" and "high". This study provided a new perspective for researchers to explore the purchase intention of cars during the epidemic. Meanwhile, we could provide a reference for the government and enterprises to develop measures related to the automobile market."


Assuntos
COVID-19 , Intenção , Humanos , Automóveis , Teorema de Bayes , COVID-19/epidemiologia , China/epidemiologia
16.
Biochem Biophys Res Commun ; 424(4): 647-50, 2012 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-22814107

RESUMO

Cyclophilin A (CyPA) is a peptidyl-prolyl cis/trans isomerase originally identified as the target of the immunosuppressive drug cyclosporine A. A number of reports have demonstrated that CyPA plays a critical role in the successful replication of viruses such as human immunodeficiency virus (HIV), hepatitis C virus (HCV), hepatitis B virus (HBV), etc. However, recent studies demonstrated that CyPA also possesses a repressive effect on the replication of some viruses like Influenza A virus and rotavirus. Moreover, CyPA could also regulate host IFN-I response to viral infections. Together, these evidences showed diverse roles of CyPA in viral infection.


Assuntos
Ciclofilina A/fisiologia , Viroses/enzimologia , Viroses/virologia , Replicação Viral , Ciclofilina A/genética , Infecções por HIV/enzimologia , Infecções por HIV/imunologia , HIV-1/fisiologia , Hepacivirus/fisiologia , Hepatite B/enzimologia , Hepatite B/imunologia , Vírus da Hepatite B/fisiologia , Hepatite C/imunologia , Humanos , Vírus da Influenza A/fisiologia , Influenza Humana/enzimologia , Influenza Humana/imunologia , Interferon Tipo I/imunologia , Viroses/imunologia
17.
BMC Cancer ; 12: 467, 2012 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-23057736

RESUMO

BACKGROUND: MTHFR 677C>T polymorphism is a genetic alteration in an enzyme involved in folate metabolism, but its effect on host susceptibility to cervical cancer is still uncertain. The aim of this study was to investigate the association between MTHFR 677C>T polymorphism and cervical cancer by performing a meta-analysis. METHODS: Pubmed, Embase, Web of Science, and the Chinese Biomedical Database (CBM) databases were searched for case-control studies investigating the association between MTHFR 677C>T polymorphism and cervical cancer. Odds ratios (OR) and 95% confidence intervals (95%CI) were used to assess this possible association. RESULTS: 11 studies with a total of 1898 cervical cancer cases and 2678 controls were included. Meta-analyses of a total 11 studies showed no association between MTHFR 677C>T polymorphism and cervical cancer using all five genetic models (All P values>0.05). However, subgroup analyses showed the odds of the homozygous TT genotype were much less in cervical cancer cases than in controls in Europeans, which implied an association between the homozygous TT genotype and cervical cancer in Europeans (For TT versus CC, fixed-effects OR=0.65, 95%CI 0.45-0.93, P=0.020, I2=0.0%). The odds for the homozygous TT genotype were greater in cervical cancer cases than in controls in East Asians, which also implied an association between the homozygous TT genotype and cervical cancer in East Asians (For TT versus CC, random-effects OR=1.66, 95%CI 1.05-2.62, P=0.029, I2=52.6%; For TT versus CT/CC, random-effects OR=1.55, 95%CI 1.09-2.22, P=0.016, I2=42.4%). Both subgroup analyses and meta-regression analyses suggested ethnicity was the major source of heterogeneity. Publication bias was not evident. CONCLUSIONS: This meta-analysis supports an association between MTHFR 677C>T polymorphism and cervical cancer, and the effect of this association may be race specific. Further studies with large sample sizes and careful design are needed to identify this association more comprehensively.


Assuntos
Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Proteínas de Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Neoplasias do Colo do Útero/genética , Feminino , Humanos
18.
ScientificWorldJournal ; 2012: 150973, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22619596

RESUMO

The effect of La on Al/NaBH(4) hydrolysis was elaborated in the present paper. Hydrogen generation amount increases but hydrogen generation rate decreases with La content increasing. There is an optimized composition that Al-15 wt% La-5 wt% NiCl(2)/NaBH(4) mixture (Al-15 wt% La-5 wt% NiCl(2)/NaBH(4) weight ratio, 1 : 3) has 126 mL g(-1 )min(-1) maximum hydrogen generation rate and 1764 mL g(-1) hydrogen generation amount within 60 min. The efficiency is 88%. Combined with NiCl(2), La has great effect on NaBH(4) hydrolysis but has little effect on Al hydrolysis. Increasing La content is helpful to decrease the particle size of Al-La-NiCl(2) in the milling process, which induces that the hydrolysis byproduct Ni(2)B is highly distributed into Al(OH)(3) and the catalytic reactivity of Ni(2)B/Al(OH)(3) is increased therefore. But hydrolysis byproduct La(OH)(3) deposits on Al surface and leads to some side effect. The Al-La-NiCl(2)/NaBH(4) mixture has good stability in low temperature and its hydrolytic performance can be improved with increasing global temperature. Therefore, the mixture has good safety and can be applied as on board hydrogen generation material.


Assuntos
Alumínio/química , Boroidretos/química , Hidrogênio/química , Lantânio/química , Níquel/química , Catálise , Hidrólise , Difração de Pó
19.
Front Psychol ; 13: 880205, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651561

RESUMO

Due to the limited work safety resources and the poor awareness of work safety from business owners with absolute decision-making power, safety accidents frequently occur in Chinese micro and small enterprises (MSEs) in high-risk industries. This study identifies the influencing factors of work safety behavior from MSEs, government safety supervision departments, and work safety service agencies. Based on the theory of planned behavior (TPB), the mechanism model of work safety behavior is built from the aspects of behavior attitude, subjective norms, behavior control cognition, past behaviors, and risk awareness of the enterprise. Based on the interview with nearly 600 MSEs in the east of China over 6 months, the results show that the work safety awareness of the business owner determines the work safety lever of the enterprise, and the work safety behavior of MSEs is a passive restraint behavior. Our findings provide a new perspective on the formation of MSEs' work safety behavior in high-risk industries.

20.
Int J Occup Saf Ergon ; 28(4): 2426-2438, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35635538

RESUMO

Employee safety behavior is a basic element of enterprise work safety. The results of accident investigations and risk assessments in enterprises indicate that management factors are some of the most important factors that affect employee safety behavior. The purpose of this study is to explore the relationship between the behavior of front-line managers (FLMs) and employee safety behavior by integrating a qualitative method, i.e., the interpretive structural model (ISM), and a quantitative method, i.e., the Bayesian network (BN). The results of the BN analysis showed that safety incentives and safety communication were the best predictors of safety participation, while safety supervision and safety control were the best predictors of safety compliance. Moreover, the results revealed that an instantaneous improvement of safety communication, safety incentives, safety supervision and safety guidance was the most effective joint measure to reach a high-level of safety behavior of employees in the workplace.


Assuntos
Gestão da Segurança , Local de Trabalho , Humanos , Teorema de Bayes , Gestão da Segurança/métodos , Comportamentos Relacionados com a Saúde
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA