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1.
Molecules ; 28(8)2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37110697

RESUMEN

The increased interest in the transition from liquid to solid polymer electrolytes (SPEs) has driven enormous research in the area polymer electrolyte technology. Solid biopolymer electrolytes (SBEs) are a special class of SPEs that are obtained from natural polymers. Recently, SBEs have been generating much attention because they are simple, inexpensive, and environmentally friendly. In this work, SBEs based on glycerol-plasticized methylcellulose/pectin/potassium phosphate (MC/PC/K3PO4) are investigated for their potential application in an electrochemical double-layer capacitor (EDLC). The structural, electrical, thermal, dielectric, and energy moduli of the SBEs were analyzed via X-ray diffractometry (XRD), Fourier transforms infrared spectroscopy (FTIR), electrochemical impedance spectroscopy (EIS), transference number measurement (TNM), and linear sweep voltammetry (LSV). The plasticizing effect of glycerol in the MC/PC/K3PO4/glycerol system was confirmed by the change in the intensity of the samples' FTIR absorption bands. The broadening of the XRD peaks demonstrates that the amorphous component of SBEs increases with increasing glycerol concentration, while EIS plots demonstrate an increase in ionic conductivity with increasing plasticizer content owing to the formation of charge-transfer complexes and the expansion of amorphous domains in polymer electrolytes (PEs). The sample containing 50% glycerol has a maximal ionic conductivity of about 7.5 × 10-4 scm-1, a broad potential window of 3.99 V, and a cation transference number of 0.959 at room temperature. Using the cyclic voltammetry (CV) test, the EDLC constructed from the sample with the highest conductivity revealed a capacitive characteristic. At 5 mVs-1, a leaf-shaped profile with a specific capacitance of 57.14 Fg-1 was measured based on the CV data.

3.
Heliyon ; 9(3): e13256, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36851968

RESUMEN

This study explores the potential of using cobalt ferrite (CF) nanoparticles grown in situ on eggshell membranes (ESM) to mitigate the increasing problem of electromagnetic interference (EMI). A simple carbonization process was adopted to synthesize CF nanoparticles on ESM. The study further examines the composites' surface morphology and chemical composition and evaluates their microwave absorption performance (MAP) at X-band frequency. Results showed that the composite of CF and ESM - CESM@CF, exhibited a strong RL peak value of -39.03 mm with an optimal thickness of 1.5 mm. The combination of CF and ESM demonstrates excellent impedance matching and EM wave attenuation. The presence of numerous interfaces, conduction loss from the morphology, interfacial polarisation, and dual influence from both CF and ESM contribute to the high MAP of the composite. CESM@CF composite is projected as an excellent biomass-based nano-composite for EM wave absorption applications.

4.
Materials (Basel) ; 15(23)2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36499791

RESUMEN

A novel technique was employed to optimize the CO2 sorption performance of spent shale at elevated pressure-temperature (PT) conditions. Four samples of spent shale prepared from the pyrolysis of oil shale under an anoxic condition were further modified with diethylenetriamine (DETA) and ethylenediamine (EDA) through the impregnation technique to investigate the variations in their physicochemical characteristics and sorption performance. The textural and structural properties of the DETA- and EDA- modified samples revealed a decrease in the surface area from tens of m2/g to a unit of m2/g due to the amine group dispersing into the available pores, but the pore sizes drastically increased to macropores and led to the creation of micropores. The N-H and C-N bonds of amine noticed on the modified samples exhibit remarkable affinity for CO2 sequestration and are confirmed to be thermally stable at higher temperatures by thermogravimetric (TG) analysis. Furthermore, the maximum sorption capacity of the spent shale increased by about 100% with the DETA modification, and the equilibrium isotherm analyses confirmed the sorption performance to support heterogenous sorption in conjunction with both monolayer and multilayer coverage since they agreed with the Sips, Toth, Langmuir, and Freundlich models. The sorption kinetics confirm that the sorption process is not limited to diffusion, and both physisorption and chemisorption have also occurred. Furthermore, the heat of enthalpy reveals an endothermic reaction observed between the CO2 and amine-modified samples as a result of the chemical bond, which will require more energy to break down. This investigation reveals that optimization of spent shale with amine functional groups can enhance its sorption behavior and the amine-modified spent shale can be a promising sorbent for CO2 sequestration from impure steams of the natural gas.

6.
Polymers (Basel) ; 14(15)2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35956570

RESUMEN

In this research, innovative green and sustainable solid polymer electrolytes (SPEs) based on plasticized methylcellulose/polyvinyl pyrrolidone/potassium carbonate (MC/PVP/K2CO3) were examined. The MC/PVP/K2CO3 SPE system with five distinct ethylene carbonate (EC) concentrations as a plasticizer was successfully designed. Frequency-dependent conductivity plots were used to investigate the conduction mechanism of the SPEs. Electrochemical potential window stability and the cation transfer number of the SPEs were studied via linear sweep voltammetry (LSV) and transference number measurement (TNM), respectively. Additionally, the structural behavior of the SPEs was analyzed using Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), X-ray diffractometry (XRD), and differential scanning calorimetry (DSC) techniques. The SPE film complexed with 15 wt.% EC measured a maximum conductivity of 3.88 × 10-4 Scm-1. According to the results of the transference number examination, cations that record a transference number of 0.949 are the primary charge carriers. An EDLC was fabricated based on the highest conducting sample that recorded a specific capacitance of 54.936 Fg-1 at 5 mVs-1.

7.
Membranes (Basel) ; 12(7)2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35877909

RESUMEN

In this research, nanocomposite solid polymer electrolytes (NCSPEs) comprising methylcellulose/pectin (MC/PC) blend as host polymer, ammonium chloride (NH4Cl) as an ion source, and zinc oxide nanoparticles (ZnO NPs) as nanofillers were synthesized via a solution cast methodology. Techniques such as Fourier transform infrared (FTIR), electrical impedance spectroscopy (EIS), and linear sweep voltammetry (LSV) were employed to characterize the electrolyte. FTIR confirmed that the polymers, NH4Cl salt, and ZnO nanofiller interact with one another appreciably. EIS demonstrated the feasibility of achieving a conductivity of 3.13 × 10-4 Scm-1 for the optimum electrolyte at room temperature. Using the dielectric formalism technique, the dielectric properties, energy modulus, and relaxation time of NH4Cl in MC/PC/NH4Cl and MC/PC/NH4Cl/ZnO systems were determined. The contribution of chain dynamics and ion mobility was acknowledged by the presence of a peak in the imaginary portion of the modulus study. The LSV measurement yielded 4.55 V for the comparatively highest conductivity NCSPE.

8.
J Parasit Dis ; 46(2): 502-510, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35692476

RESUMEN

Zoonotic cutaneous leishmaniasis (ZCL) caused by Leishmania major is an important endemic disease and a major public health concern in Iran. Following an outbreak of leishmaniasis in 2013 in one of the important foci in Iran, the researchers were prompted to determine the underlying causes of the epidemic. Adult sand flies were collected using sticky traps and aspirating tubes and infection with Leishmania parasites was evaluated. Also, rodents were captured using Sherman live traps and stray dogs were hunted and were tested for the presence of leishmanial infection. Active case detection was also conducted and data related to each household were recorded using a researcher-designed form. Nested PCR and PCR-RLFP techniques were employed to determine Leishmania infection in the samples. Phlebotomus papatasi was the most dominant species among the 7 different species of sand flies collected in this study. Sergentomyia clydei, Sergentomyia theodori, and Sergentomyia grekovi were identified for the first time in the study area. 20% of collected Ph. papatasi species and one Meriones libycus were infected with Leishmania major. Stray dogs demonstrated no lesions on different parts of their body. The relative frequency of active lesions and scars on the dogs were respectively 5.49% and 1.23% in 2013 and 5.82% and 0.56% in 2014. The highest number of ZCL cases due to L. major was recorded in Ardestan city. Phlebotomus papatasi is the main vector and M. libycus seems to be the primary reservoir host of ZCL in the suburbs of this city. Furthermore, due to the low density of rodent reservoir hosts in the study area, we support the hypothesis that humans may have had a role in maintaining the parasite cycle in the population.

9.
J Arthropod Borne Dis ; 16(4): 278-287, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37159595

RESUMEN

Background: Leishmaniasis is one of the most important vector-borne and neglected tropical diseases in many parts of the world. The main objective of this study was to determine the biodiversity of phlebotomine sand flies (Diptera: Psychodidae, Phlebotominae) in Khuzestan and Kermanshah Provinces of Iran. Methods: Sampling was conducted in Khuzestan and Kermanshah Provinces using sticky paper traps and CDC light traps. The samples were then stored in 96% alcohol-containing vials, mounted, and identified. Afterward, the alpha diversity (using Simpson's, Shannon-Weiner's diversity, evenness, Maghalef's, Menhinick's, Hill N 1 and N 2 indices) and beta diversity indices (using Sorensen's and Jaccard's coefficients) were calculated. Results: A total of 4302 sand flies were caught and identified which comprised mostly of Phlebotomus papatasi, Ph. alexandri and Ph. sergenti. It was found that among the four counties of Ahvaz, Shush, Shushtar and Dezful in Khuzestan Province, Shush had the lowest, and Shushtar, the highest amount of species diversity and evenness. In the four studied counties of Kermanshah Province, species diversity in Kermanshah County had the lowest amount and Sarpol-e-Zahab, the highest. The species richness in Kermanshah County was the lowest, while Qasr-e-Shirin County had the highest amount. Conclusion: An overview of the biodiversity of phlebotomine sand flies in Kermanshah County in Kermanshah Province, and Shush County in Khuzestan Province, showed less stability in community structure of these vectors, which can be counted as an alarm for emerging dominant vectors among the studied counties and have the potential to increase the prevalence of leishmaniasis.

10.
J Arthropod Borne Dis ; 14(1): 8-16, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32766344

RESUMEN

BACKGROUND: Visceral and cutaneous leishmaniasis are common in some areas of Iran and consider as health problems. Phlebotomus alexandri has been incriminated as a suspected vector for the both form of leishmaniasis. METHODS: This study was carried out in 4 western provinces of Iran. Sand flies were collected using sticky traps and light traps from indoor and outdoor resting places. Nested PCR was employed to detect Leishmania parasites among collected sand flies. RESULTS: Seven hundred and twenty two P. alexandri females were collected and pooled in 179 batches. Results of nested PCR showed, out of 9 samples from East Azerbaijan Province, only one sample was infected by Leishmania infantum. Of 34 individual and pooled samples from Kermanshah Province, only one pooled sample was infected with Leishmania major and among 30 individual and pooled samples in Fars Province, five specimens were infected by L. major, L. infantum, Leishmania donovani and Leishmania tropica. Furthermore, out of 108 individual and pooled samples from Khuzestan Province, 10 samples showed infection with L. major and L. infantum. CONCLUSION: The results of this study showed that P. alexandri is more active in hot zones than in moderate zones and this species may be considered as a permissive species.

11.
Sci Rep ; 8(1): 3404, 2018 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-29467510

RESUMEN

A layered nanoreactor (zinc hydroxide gallate/nitrate nanohybrid) has been designed as a nano-vessel to confine the gallate/nitrate reaction inside zinc hydroxide layers for production of metal/nitrogen-doped carbon catalysts. Metals (Fe2+, Co2+ and Ni2+) doped and bare zinc hydroxide nitrates (ZHN) were synthesized as the α-phase hydroxide hosts. By an incomplete ion-exchange process, nitrate anions between the layers of the hosts were then partially replaced by the gallate anions to produce the layered nanoreactors. Under heat-treatment, the reaction between the remaining un-exchanged nitrate anions and the organic moiety inside the basal spacing of each nanohybrid plate resulted in obtaining highly porous 3D metal/nitrogen-doped carbon nanosheets. These catalysts were then used as extremely efficient electrocatalysts for catalyzing oxygen reduction reaction (ORR). This study is intended to show the way to get maximum electrocatalytic activity of the metal/N-doped carbon catalysts toward the ORR. This exceptionally high ORR performance originates from the increased available surface, the best pore size range and the uniform distribution of the active sites in the produced catalysts, all provided by the use of new idea of the layered nanoreactor.

12.
J Psycholinguist Res ; 47(4): 859-869, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29404913

RESUMEN

Vocabulary learning has always been a great concern and has attracted the attention of many researchers. Among the vocabulary learning hypotheses, involvement load hypothesis and technique feature analysis have been proposed which attempt to bring some concepts like noticing, motivation, and generation into focus. In the current study, 90 high proficiency EFL students were assigned into three vocabulary tasks of sentence making, composition, and reading comprehension in order to examine the power of involvement load hypothesis and technique feature analysis frameworks in predicting vocabulary learning. It was unraveled that involvement load hypothesis cannot be a good predictor, and technique feature analysis was a good predictor in pretest to posttest score change and not in during-task activity. The implications of the results will be discussed in the light of preparing vocabulary tasks.


Asunto(s)
Comprensión/fisiología , Aprendizaje/fisiología , Lectura , Vocabulario , Adolescente , Adulto , Femenino , Humanos , Masculino , Estudiantes , Adulto Joven
13.
J Psycholinguist Res ; 47(4): 803-815, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29368141

RESUMEN

Research in multilingualism has shown that bilinguals have enhanced executive function (e.g., Donnelly et al. in Proceedings of the 37th annual conference of the cognitive science society 2015; Green in Bilingualism Lang Cognit 1(02):67-81, 1998. https://doi.org/10.1017/S1366728998000133 ); however, this with many other areas in multilingualism have been questioned like their non-verbal reasoning or their metacognitive ability. This study attempts to explore learning more than one languages in the field of metacognitive abilities. Three groups of monolinguals, bilinguals, and trilinguals were explored to examine the effect of language learning on enhancing or weakening accuracy and response time in metacognitive processing. Conducting dot discrimination task, we found that multilingualism might have some advantages in this field. As cognition and metacognitive abilities demonstrated no positive correlation in this study, we might conclude that executive functioning can not bring about higher order functioning for the individuals. Nevertheless, monolinguals did the task in the least period of time with the least accuracy. Trilinguals, on the contrary, could respond more accurately with an average speed. Accuracy, difficulty, and response time choice in metacognitive processing were discussed for each group. It is concluded that multilingualism might have different effects on higher-order decision making abilities.


Asunto(s)
Lenguaje , Metacognición/fisiología , Multilingüismo , Tiempo de Reacción/fisiología , Adolescente , Adulto , Cognición/fisiología , Discriminación en Psicología/fisiología , Función Ejecutiva/fisiología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Solución de Problemas/fisiología , Adulto Joven
14.
J Arthropod Borne Dis ; 9(1): 84-97, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26114146

RESUMEN

BACKGROUND: Female sand flies of subgenus Adlerius are considered as probable vectors of visceral leishmaniasis in Iran. The objective of this study was to determine the morphological and genotypic variations in the populations of this subgenus in the country. METHODS: Sand flies collected using sticky traps from 17 provinces during 2008-2010. The morphometric measurements were conducted with an Ocular Micrometer. Data was analyzed by SPSS. The Cytb gene was used to estimate population genetic diversity and identify the female specimens. UPGMA phenetic tree was used for DNA haplotypes of Cytb gene. RESULTS: Six species of subgenus Adlerius identified from which one species, P. (Adlerius) kabulensis, is new record. The identification key is provided for males. Results revealed the molecular systematic in the species of subgenus Adlerius and determine the relationship of three females of P. comatus, P. balcanicus and P. halepensis. CONCLUSION: The positions of three females and the males in the UPGMA tree are correct and the similarities among them confirm our results. The branches of each species are not genetically distinct which justify the overlapping morphological characters among them. Molecular sequencing of Cytb-mtDNA haplotypes can be used for female identification for different species of subgenus Adlerius in Iran.

15.
Front Public Health ; 3: 14, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25699245

RESUMEN

Cutaneous leishmaniasis is the most important health problem in the city of Bushehr, southwestern Iran. The objective of the study was to determine some ecological aspects of sand flies in the city during 2010-2011. Sand flies were collected monthly from outdoors and indoors by sticky traps at four selected districts of the city. They were also dissected and examined by nested-PCR for identification of the parasite during August-September of 2011. A total of 1234 adult sand flies were collected and 6 species including 3 of Genus Phlebotomus and 3 of Genus Sergentomyia were identified. Four species including P. papatasi (3.98%), P. sergenti (1.14%), S. tiberiadis (87.18%), and S. baghdadis (7.7%) were found indoors. Six species including P. papatasi (3.47%), P. sergenti (3.17%), P. alexandri (0.1%), S. tiberiadis (77.74%), S. baghdadis (15.41%), and one female of S. clydei (0.11%) were collected from outdoors. Sand flies started to appear from March and disappear at the end of January. There was only one peak in the density curve in July. The study revealed that S. tiberiadis and S. baghdadis could enter indoors which 89 and 81.8% of them were found blood-fed, respectively. Moreover, P. papatasi, S. tiberiadis, and S. baghdadis were active indoors and outdoors in most months of the year. Nested-PCR of P. papatasi females was positive against kinetoplast DNA of L. major and L. turanica and also mixed natural infections were found by L. gerbilli and L. turanica. Moreover, mixed infections by L. major and L. turanica were observed in this species. Sergentomyia clydei and S. tiberiadis were found to be negative to any DNA of Leishmania species. Phlebotomus sergenti females were found infected with DNA of L. turanica and this is the first report of natural infection and detection of the parasite from this sand fly species in worldwide.

16.
J Arthropod Borne Dis ; 8(1): 35-42, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25629063

RESUMEN

BACKGROUND: The aim was to survey the specific factors, which cause to decrease blood feeding of mosquitoes important to succeed vector control. METHODS: Larval collection was carried out from fixed and variable breeding places of Yazd County, central Iran in 2009. Autogeny-Anautogeny, Stenogamy-Eurygamy, and blood preference of Culex pipiens were studied using standard mosquito cages blood meal source for Cx. pipiens females considered as the chickens and human and fed females were kept in insectary condition (16:8 L: D, 27±3 °C and 70±10% RH). The data were analyzed using SPSS Ver. 11.5 soft ware. RESULTS: Totally, 96 females' mosquitoes were tested for Stenogamy versus Eurygamy and 122 for blood preference assay. In the small cages (20 × 20 × 20cm) and large cage (60 × 40 × 60cm), the ability of mating and insemination rates were 60.0 and 67.0%, respectively. In spite of Cx. pipiens fed from sucrose 5%, none of them laying eggs in 60 × 40 × 60 cages during the study. This finding indicated the Anautogeny behavior of this species. This species was found of low tendency to human blood and almost 4 fold fed on chicken. CONCLUSION: The occurrence of Steno-Eurygamy, Anautogeny, and Ornithophilic behaviors of Cx. Pipiens was noted. More studies need to be carried out about the bionomics of this species to gain more data about the ecophysiological and behavioral characteristics in other parts of Iran.

17.
J Arthropod Borne Dis ; 7(1): 1-7, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23785689

RESUMEN

BACKGROUND: Sand flies of subgenus Adlerius has a wide geographical distribution in Iran and are mostly found in wild form in mountainous areas. They are always considered as probable vectors of visceral leishmaniasis. The objective of this study was to determine the Adlerius species and its composition in an endemic focus of zoonotic visceral leishmaniasis in northwest of the country. METHODS: Sand flies were collected from 6 different areas of Azarbaijan-e-Sharqi Province using sticky paper traps from August to September which is active season for sand flies in this area, in 2009. The flies were mounted and identified. The length of third antennal segments, ascoid, labrum, coxite, surstyle, style, aedeagus, genital filament, genital pump, width of style, and the end of aedeagus were measured and the number of costal hairs group was also counted as the morphological characters. RESULTS: A total of 30 adult sand flies, (26 males and 4 females) including Phlebotomus halepensis (46.8%), P. longiductus (13.3%), P. balcanicus (23.3%), P. comatus (3.3%), and Adlerius spp. (13.3%) belong to subgenus Adlerius were identified respectively in 6 counties. One P. comatus male was captured in front of a cave located in the hillside of a mountain covered with the vegetation in Varzeqan area. CONCLUSION: The presence of at least 5 species of the subgenus Adlerius in Azarbaijan-e-Sharqi Province, an endemic focus of zoonotic visceral leishmaniasis in Iran, shows that the risk of parasite transmission among man and reservoir animals is high during the active season of sand flies. P. comatus is a new record for Iran and needs to be added to the list of Iranian phlebotomines of subgenus Adlerius.

18.
J Arthropod Borne Dis ; 7(2): 113-21, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24409436

RESUMEN

BACKGROUND: Cutaneous leishmaniasis (CL) represents the most frequent vector borne parasitoses in Iran. The objective of this study was to determine the epidemiological features of CL including human infection and the reservoir host in the city of Bushehr, Bushehr Province, Iran during 2010-2011. METHODS: Studies on human infection was carried out on 2962 school children aged 7-14 years old from 60 primary schools and among 400 households with a total population of 1568 in four infected districts of the city in December 2010. Serosity materials from patients on glass slides were collected for molecular identification of causative agent. Rodents were caught by Sherman traps and examined for identification of the parasite. RESULTS: Prevalence of scars and ulcers among the inhabitants were 5.86% and 0.12% respectively. Molecular study indicated the presence of two coexisting species: Leishmania major and L. tropica among patients. The scar rate was 1.24% but no ulcers were seen among the students. Nineteen rodents were caught and identified as Tatera indica (47.4%) and Rattus norvegicus (52.6%). Specimens from 7 T. indica and 9 R. norvegicus were examined by two techniques, microscopic examination and nested-PCR. Out of 7 T. indica, 14.3% were infected with L. major and 42.9% with L. turanica by nested-PCR. Out of 9 R. norvegicus 22.2% were infected with L. turanica and 11.1% with L. gerbilli. CONCLUSION: Based on this survey L. major and L. tropica are the causative agents of the disease among patients and T. indica plays a predominant role in the dissemination of L. major in the city.

19.
Int J Mol Sci ; 13(7): 8540-8548, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22942718

RESUMEN

The sol-gel method was carried out to synthesize nanosized Yttrium Iron Garnet (YIG). The nanomaterials with ferrite structure were heat-treated at different temperatures from 500 to 1000 °C. The phase identification, morphology and functional groups of the prepared samples were characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR), respectively. The YIG ferrite nanopowder was composited with polyvinylidene fluoride (PVDF) by a solution casting method. The magnitudes of reflection and transmission coefficients of PVDF/YIG containing 6, 10 and 13% YIG, respectively, were measured using rectangular waveguide in conjunction with a microwave vector network analyzer (VNA) in X-band frequencies. The results indicate that the presence of YIG in polymer composites causes an increase in reflection coefficient and decrease in transmission coefficient of the polymer.


Asunto(s)
Hierro/química , Nanocompuestos/química , Polivinilos/química , Itrio/química , Microscopía Electrónica de Rastreo , Microondas , Nanocompuestos/ultraestructura , Tamaño de la Partícula , Difracción de Polvo , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Difracción de Rayos X
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