The gout is mainly found due to accumulation of uric acid crystals into the joints which produces the inflammatory symptoms. Thus, it is highly demanded to detect uric acid from our body. Herein, we prepare a composite material of cobalt oxide (Co3O4) with hydroxide functionalized multi-walled carbon nanotubes (MWCNTs) by hydrothermal method. The composite material is used for the modification of glassy carbon electrode (GCE) and investigated for the electrochemical determination of uric acid (UA). The analytical techniques such as scanning electron microscopy (SEM), powder X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and Fourier Infra-red spectroscopy (FTIR) are used to characterize the composite material. The Co3O4 exhibits a dendrite morphology and very well chemically coupled with MWCNTs. The elemental analysis confirms the presence of cobalt (Co), oxygen (O) and carbon (C) as main constituent of the composite material. The Co3O4 exhibitsa cubic unit cell crystallography in the composite system. The FTIR study reveals the characteristic bands of Co–O bands in the composite material. The cyclic voltammetry isused to study the electrochemical properties of prepared materials. The composite sample with highest percentage of MWCNTs shows an excellent electrochemical activity towards the oxidation of uric acid in phosphate buffer solution pH 7.3. The enzyme free uric acid sensor possesses a linear range of 0.1 mM to 3 mM with a quantified limit of detection of 0.005?±?0.0023 mM. The modified electrode is stable, selective, and very sensitive towards uric acid, therefore it may be used for the monitoring of uric acid from clinical samples. The proposed composite material can be of great interest for energy and biomedical fields.
The present study demonstrates the synthesis and antimicrobial activity of the p-tetranitrocalix[4]arene (3). The microbial activity was determined against a variety of microorganisms, i.e., Gram-positive and Gram-negative bacterial strains such as Staphylococcus aureus ATCC 10231, Streptococcus viridans ATCC 12392, Escherichia coli ATCC 8739, as well as some fungal species including Aspergillus niger ATCC 16404, Aspergillus flavus ATCC 90906, and Candida albicans ATCC 32333. Kirby-Bauer well agar diffusion method was employed for the determination of antimicrobial activity. All the microorganisms were applied to a selective agar medium (Mueller Hinton Agar) for growth. It was observed that compound 3 is considerably effective against selected microorganisms. The MIC values were also evaluated. Thus, from the results it could be deduced that compound 3 may be a valuable addition to the therapeutic index. 相似文献
A series of single phase X-type hexagonal ferrites with concentration Sr2?xNdxNi2Fe28?yCoyO46 (x = 0.02, 0.04, 0.06, 0.08, 0.10 and y = 0.1, 0.2, 0.3, 0.4, 0.5) has been prepared by sol-gel method sintered at 1250 °C for 6 h. The x-ray diffraction analysis reveals the single phase of X-type hexagonal ferrites. The particle size was calculated by using SEM and TEM. The ferrite substituted with Nd3+ and Co2+ has average particle size in the range of 40-50 nm. The room temperature electrical resistivity experiences the significant enhancement from a value of 1.1 × 107 to 2.03 × 108 Ωcm with the increase in Nd3+ and Co2+ concentration. The dielectric constant exhibits high value at low frequencies and decreases with the increase of frequency. The tangent dielectric loss shows the abnormal behavior which can be explained on the basis of hopping between the Fe2+ and Fe3+ ions on octahedral sites. The maximum value of tangent loss at low frequencies reflects the application of these materials in medium frequency devices (MF). 相似文献
Compliance with safety behaviors is often associated with longer term benefits, but may require some short-term sacrifices. This study examines the extent to which consideration of future safety consequences (CFSC) predicts employee safety outcomes.
Methods
Two field studies were conducted to evaluate the reliability and validity of the newly developed Consideration of Future Safety Consequences (CFSC) scale. Surveys containing the CFSC scale and other measures of safety attitudes, behaviors, and outcomes were administered during working hours to a sample of 128 pulp and paper mill employees; after revising the CFSC scale based on these initial results, follow-up survey data were collected in a second sample of 212 copper miners.
Results
In Study I, CFSC was predictive of employee safety knowledge and motivation, compliance, safety citizenship behaviors, accident reporting attitudes and behaviors, and workplace injuries – even after accounting for conscientiousness and demographic variables. Moreover, the effects of CFSC on the variables generally appear to be direct, as opposed to mediated by safety knowledge or motivation. These findings were largely replicated in Study II.
Conclusions
CFSC appears to be an important personality construct that may predict those individuals who are more likely to comply with safety rules and have more positive safety outcomes. Future research should examine the longitudinal stability of CFSC to determine the extent to which this construct is a stable trait, rather than a safety attitude amenable to change over time or following an intervention. 相似文献