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1.
A differential pulse polarography (DPP) for the simultaneous determination of 2-nitrophenol and 4-nitrophenol was proposed.
It was found that under optimum experimental conditions (pH = 5, scan rate = 5 mV/s, pulse amplitude = −50 mV), 2-nitrophenol
and 4-nitrophenol had well-defined polarographic reduction waves with peak potentials at −317 and −406 mV, respectively. In
the mixture of two compounds overlapping polarographic peaks were observed. In this study, support vector regression (SVR)
was applied to resolve the overlapped polarograms. Furthermore, a comparison was made between the performance of SVR and partial
least square (PLS) on data set. The results demonstrated that SVR is a better well-performing alternative for the analysis
and modeling of DPP data than the commonly applied PLS technique. The proposed method was used for the determination of 2-nitrophenol
and 4-nitrophenol in industrial waste water. 相似文献
2.
Jadoun Sapana Chauhan Narendra Pal Singh Zarrintaj Payam Barani Mahmood Varma Rajender S. Chinnam Sampath Rahdar Abbas 《Environmental Chemistry Letters》2022,20(5):3153-3197
Environmental Chemistry Letters - Nanoparticles synthesis under green conditions has been performed using natural resources to diminish the use of toxic chemicals. For instance, microbial synthesis... 相似文献
3.
Bazzazpour Shahriyar Rahmatinia Masoumeh Mohebbi Seyed Reza Hadei Mostafa Shahsavani Abbas Hopke Philip K. Houshmand Behzad Raeisi Alireza Jafari Ahmad Jonidi Yarahmadi Maryam Farhadi Mohsen Hasanzadeh Vajihe Kermani Majid Vaziri Mohmmad Hossien Tanhaei Mohammad Zali Mohammad Reza Alipour Mohammad Reza 《Environmental science and pollution research international》2022,29(57):85586-85594
Environmental Science and Pollution Research - In the indoor environment of dental clinics, dental personnel and patients are exposed to a risk of infection because of the transmission of... 相似文献
4.
Hosein Ghaedi Payam Kalhor Ming Zhao Peter T. Clough Edward J. Anthony Paul S. Fennell 《Frontiers of Environmental Science & Engineering》2022,16(7):92
5.
A novel nanocomposite based on incorporation of multiwalled carbon nanotubes (MWCNTs) in polyvinyl chloride (PVC) was prepared. Proposed nanocomposite was coated on stainless steel wire by deep coating. Composition of nanocomposite was optimized based on results of morphological studies using scanning electron microscopy. The best composition (83% MWCNTs:17% PVC) was applied as a solid phase microextraction fiber. Complex mixture of aromatic (BTEX) and aliphatic hydrocarbons (C5–C34) were selected as model analytes, and performance of proposed fiber in extraction of the studied compounds from water and soil samples was evaluated. Analytical merits of the method for water samples (LODs = 0.10–1.10 ng L−1, r2 = 0.9940–0.9994) and for soil samples (LODs = 0.10–0.77 ng kg−1, r2 = 0.9946–0.9994) showed excellent characteristics of it in ultra trace determination of petroleum type environmental pollutants. Finally, the method was used for determination of target analytes in river water, industrial effluent and soil samples. 相似文献
6.
7.
Dadvand P Basagaña X Figueras F Amoly E Tobias A de Nazelle A Querol X Sunyer J Nieuwenhuijsen MJ 《Journal of environmental monitoring : JEM》2011,13(11):3222-3228
Desert dust is one of the natural contributors to atmospheric particulate matter worldwide. Although particulate pollution has been shown to adversely affect pregnancy, the available evidence on the impact of dust episodes on pregnancy is very scarce. The aim of this study was to evaluate the impact of Saharan dust episodes on pregnancy complications (preeclampsia and bacteriuria) and outcomes (birth weight and gestational age at delivery). This study was based on a cohort of births (N = 3565) that occurred in a major university hospital in Barcelona during 2003-2005. To determine Saharan dust episodes, we developed a two-stage approach based on meteorological evidence of the presence of Saharan dust cloud over the region and unusually high levels of particulate levels on the ground while taking account of traffic sources. The associations between the number of Saharan dust episodes during whole pregnancy as well as each pregnancy trimester and pregnancy complications and outcomes were analysed. There were 152 days (out of 838 days) with Saharan dust cloud over the region from which 45 days were determined as episodic days. We did not observe any statistically significant harmful effect of Saharan dust episodes on our included pregnancy complications and outcomes. However, we observed a small but statistically significant increase in gestational age at delivery in association with the number of episodic days during the third trimester and whole pregnancy (0.8 and 0.5 days respectively). Our findings were not suggestive for any adverse effect of Saharan dust episodes on our included pregnancy complications and outcomes. 相似文献
8.
Mohamad Sadegh Ghasemi Payam Hosseinzadeh Farhad Zamani Hossein Ahmadpoor 《International journal of occupational safety and ergonomics》2013,19(4):519-523
Background. Work-related musculoskeletal disorders (WMSDs) are injuries and disorders that affect the body’s movement and musculoskeletal system. Awkward postures represent one of the major ergonomic risk factors that cause WMSDs among sonographers while working with an ultrasound transducer. This study aimed to design and evaluate a new holder for the ultrasound transducer. Materials and methods. In the first phase a new holder was designed for the transducer, considering design principles. Evaluation of the new holder was then carried out by electrogoniometry and a locally perceived discomfort (LPD) scale. Results. The application of design principles to the new holder resulted in an improvement of wrist posture and comfort. Wrist angles in extension, flexion, radial deviation and ulnar deviation were lower with utilization of the new holder. The severity of discomfort based on the LPD method in the two modes of work with and without the new holder was reported with values of 1.3 and 1.8, respectively (p?<?0.05). Conclusion. Overall, this study indicated that applying ergonomics design principles was effective in minimizing wrist deviation and increasing comfort while working with the new holder. 相似文献
9.
Findings in multiattribute decision research were used as a basis for predicting the effects of help-wanted advertisement characteristics on vacancy attractiveness. In the first experiment, undergraduate students were presented with entry-level service job advertisements differing in attribute set size, attribute relevance, and pay ambiguity. Results revealed strong evidence for a set-size effect, with ads containing more (relevant or irrelevant) attributes increasing the attractiveness of the vacancies being advertised. Pay ambiguity decreased the attractiveness of vacancies with ads containing a small set of attributes. A second experiment presented students with the same advertisements, except that the small-set ads were physically enlarged to equal the size of the large-set ads. Results replicated the (large) set-size effect only for relevant-attribute ads. Also, pay ambiguity increased the attractiveness of vacancies promoted by ads containing a larger amount of relevant attributes. We conclude that merely adding relevant attribute information to help-wanted advertisements can lead to the inference that the jobs promoted in the ads are more attractive. Moreover, we tentatively suggest that pay ambiguity can lead to pessimistic inferences about pay for ads containing less information, and optimistic inferences about pay for ads containing more information. © 1998 John Wiley & Sons, Ltd. 相似文献
10.
A Computational Fluid Dynamic Model for Prediction of Organic Dyes Adsorption from Aqueous Solutions
F. Doulati Ardejani Kh. Badii F. Farhadi M. Aziz Saberi B. Jodeiri Shokri 《Environmental Modeling and Assessment》2012,17(5):505-513
Modelling of the removal of synthetic dyes from aqueous solutions by adsorbents is important to develop an appropriate treatment plan using adsorption process. This paper presents a computational fluid dynamic model incorporating the Langmuir isotherm scheme and second-order kinetic expression to describe the adsorption process. The governing equation of the model was numerically solved using PHOENICS software to simulate synthetic dyes adsorption from the aqueous system. The experimental results presented in this study and taken from the literature for the removal of synthetic dyes were compared with those results predicted by the numerical model. The predicted outputs of the model match the experimental measurements satisfactory. A sensitivity analysis of the major parameters that influence the percent of dye removal from solution phase has been carried out. Three of the main parameters taken into account were the kinetic rate constant, amount of dye adsorbed at equilibrium and the Langmuir isotherm constant. It was found that the model is most sensitive to the amount of dye adsorbed at equilibrium. This effect is most obvious at the early stages of the adsorption process when the rate of dye removal is very fast. Quantification of the reaction mechanism allows developing an appropriate remediation strategy based on the adsorption process. 相似文献