Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
J Colloid Interface Sci ; 512: 151-157, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29059548

RESUMO

In present work, for improving the electrochemical performance of conductive polymer, poly ortho aminophenol (POAP)/1-Butyl-3-methylimidazolium Chloride, [bmim]Cl composite films have been fabricated by POAP electropolymerization in the presence of [bmim]Cl as active electrodes for electrochemical supercapacitors. Different electrochemical methods including galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy have been applied to study the system performance. Analysis of DFT-B3LYP/6-31G∗ computational results, and AIM (atom-in-molecule) theory calculations, show that the atomic-scale electronic properties are generally depend on the bonding and electronic molecular structures (and thus their variation with the external bias in real nano-electrochemical circuits). The supercapacity behavior of the composite film was attributed to the (i) high active surface area of the composite, (ii) charge transfer along the polymer chain due to the conjugation form of the polymer and finally (iii) synergism effect between conductive polymer and [bmim]Cl.

2.
J Colloid Interface Sci ; 505: 1158-1164, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28715859

RESUMO

In present work, for improving the electrochemical performance of conductive polymer, POAP/3-methyl-1-[2-(2-{2-[2-[(3-methyl-1-H-imidazol-3-ium-1-yl)ethoxy]ethoxy}-ethoxy)ethyl]-1-H-imidazol-3-ium dichloride (MIEID) composite films have been fabricated by poly ortho aminophenol (POAP) electropolymerization in the presence of MIEID as active electrodes for electrochemical supercapacitors. Different electrochemical methods including galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy have been applied to study the system performance. Analysis of density functional theory (DFT) results show that the atomic-scale electronic properties are generally depend on the bonding and electronic molecular structures (and thus their variation with the external bias in real nano-electrochemical circuits). Composite film kept more than 90% percent of its capacitance after 1000 charging-discharging cycles, while the coulombic efficiency (η) is as high as 95%. Results suggesting composite film can be used as supercapacitor electrode material with excellent specific capacitance (487Fg-1) which indicates this material is a promising electrode material used in high power applications.

3.
J Colloid Interface Sci ; 503: 10-16, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28500935

RESUMO

In present work, for improving the electrochemical performance of conductive polymer, POAP/1-octadecyl-3-methylimidazolium Bromide ([OMD]Br) composite films have been fabricated by POAP electropolymerization in the presence of [OMD]Br as active electrodes for electrochemical supercapacitors. Different electrochemical methods including galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy have been applied to study the system performance. Analyses of DFT results show that the atomic-scale electronic properties are generally depend on the bonding and electronic molecular structures (and thus their variation with the external bias in real nano-electrochemical circuits). The supercapacity behavior of the composite film was attributed to the (i) high active surface area of the composite, (ii) charge transfer along the polymer chain due to the conjugation form of the polymer and finally (iii) synergism effect between conductive polymer and [OMD]Br.

4.
J Colloid Interface Sci ; 500: 315-320, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28412638

RESUMO

This study demonstrates a method for improving supercapacitive performance of electrochemically synthesized conductive polymer. In this regards, 1-Butyl-3-methyl imidazolium hexafluorophosphate (BI) as a new high efficient ionic liquid was synthesized using chemical approach and then fabricated POAP/BI films by electro-polymerization of POAP in the presence of BI to serve as the active electrode for electrochemical supercapacitor. Theoretical study (AIM) and electrochemical analysis have been used for characterization of ionic liquid and POAP/BI composite film. Different electrochemical methods including galvanostatic charge-discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy are carried out in order to investigate the performance of the system. This work introduces new most efficient materials for electrochemical redox capacitors with advantages including ease synthesis, high active surface area and stability in an aqueous electrolyte.

5.
J Colloid Interface Sci ; 497: 258-265, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28285054

RESUMO

In this work, we synthesized amine functionalized graphene oxide (GOA), by using of 1-methyl, 3-butyl Imidazole ionic liquid, triphenylphosphine, 1,6-diamino hexane in DMSO medium. Afterward, dried GOA used for sulfonated graphene oxide (GOS). For improving electrochemical properties of the poly ortho aminophenol (POAP), we fabricated POAP/GOS films by electro-polymerization of POAP in the presence of GOS to serve as the active electrode for electrochemical supercapacitor. Different electrochemical methods including galvanostatic charge-discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy are carried out in order to investigate the performance of the system. Finally, the local charge and energy transfer of the molecular system is calculated, using DFT/AIM theories. Results show that the oxygen and nitrogen atoms of phenyl (Ph)/(Ph-OH) rings and -Ph-CO-N-R-N-R″ -SO3H ended functional group, play domain role in intra-molecular charge and energy transfer. The major aim of this computational study method is to propose or effective design electro-chemical molecular systems having different atomic basins/functional groups response (sensitivities) to external voltage. This work introduces new most efficient materials for electrochemical redox capacitors with advantages including ease synthesis, high active surface area and stability in an aqueous electrolyte.

6.
J Colloid Interface Sci ; 490: 695-702, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27978454

RESUMO

Magnetic functional graphene oxide (MFGO) has been synthesized in this work using FeCl4- magnetic anion paired with 1-methyl imidazolium cation. Hybrid poly ortho aminophenol (POAP)/MFGO films have then been prepared via POAP electropolymerization in the presence of MFGO nanosheets, serving as active electrodes for electrochemical supercapacitors. The FeCl4- functional group in MFGO plays a major part in atomic scale charge/energy transfer and consequently intramolecular electrochemical phenomena in MFGO systems, as shown by the theoretical results. POAP/MFGO composite films have been characterized by surface and electrochemical analyses. The performance of the system has been investigated by various electrochemical methods such as galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy. Novel nanocomposite compounds have been developed in this work for electrochemical redox capacitors. The advantages of these compounds include simple synthesis method, high active surface area and stability in aqueous electrolytes.

7.
J Colloid Interface Sci ; 490: 444-451, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27914344

RESUMO

Inhibition performance of Thymus vulgaris plant leaves extract (thyme) as environmentally friendly (green) inhibitor for the corrosion protection of stainless steel (SS) type 304 in 1.0molL-1 HCl solution was studied by potentiodynamic polarization, electrochemical impedance (EIS) and electrochemical noise measurements (EN) techniques. The EN data were analyzed with FFT technique to make the spectral power density plots. The calculations were performed by MATLAB 2014a software. Geometry optimization and calculation of the structural and electronic properties of the molecular system of inhibitor have been carried out using UB3LYP/6-311++G∗∗ level. Moreover, the results obtained from electrochemical noise analysis were compared with potentiodynamic polarization and electrochemical impedance spectroscopy. All of the used techniques showed positive effect of green inhibitor with increasing inhibitor concentration.


Assuntos
Extratos Vegetais/química , Aço Inoxidável/química , Thymus (Planta)/química , Corrosão , Espectroscopia Dielétrica , Química Verde , Modelos Moleculares
8.
J Colloid Interface Sci ; 490: 91-96, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27870964

RESUMO

In this paper firstly, 1-methyl-3-methylimidazolium bromide (MB) as a new high efficient ionic liquid was synthesized using chemical approach and then fabricated POAP/MB films by electro-polymerization of POAP in the presence of MB to serve as the active electrode for electrochemical supercapacitor. Theoretical study (AIM) and electrochemical analysis have been used for characterization of ionic liquid and POAP/MB composite film. Different electrochemical methods including galvanostatic charge-discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy are carried out in order to investigate the performance of the system. This work introduces new most efficient materials for electrochemical redox capacitors with advantages including ease synthesis, high active surface area and stability in an aqueous electrolyte.

9.
Ann Burns Fire Disasters ; 29(1): 14-17, 2016 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-27857645

RESUMO

Burn injuries put a huge financial burden on patients and healthcare systems. They are the 8th leading cause of mortality and the 13th most common cause of morbidity in our country. We used data from our Burn Registry Program to evaluate risk factors for mortality and lethal area fifty percent (LA50) in all burn patients admitted over two years. We used multiple logistic regressions to identify risk factors for mortality. LA50 is a reliable aggregate index for hospital care quality and a good measure for comparing results, also with those of other countries. 28,690 burn patients sought medical attention in the Emergency Department, and 1721 of them were admitted. Male to female ratio was 1,75:1. 514 patients were under 15 years old. Median age was 25 (range: 3 months - 93 years). Overall, probability of death was 8.4%. LA50 was 62.31% (CI 95%: 56.57-70.02) for patients aged 15 and over and 72.52% (CI 95%: 61.01-100) for those under 15. In the final model, we found that Adjusted OR was significant for age, female sex, TBSA and inhalation injury (P < 0.05). LA50 values showed that children tolerate more extensive burns. Female sex, burn size, age and inhalation injury were the main risk factors for death. Authorities should pay special attention to these variables, especially in prevention programs, to reduce mortality and improve patient outcome. Children have better outcome than adults given equal burn size. Suicide rates are higher for women than men in our country.


Les brûlures sont responsables d'une lourde charge financière pour les patients et les systèmes de santé. Elles représentent dans notre pays la 8ème cause de mortalité et la 13ème cause de morbidité. En utilisant les données de 2 ans du programme de surveillance des brûlures, nous avons évalué les facteurs de risque de mortalité (par régression logistique) et la surface létale 50% (SL50). Cette mortalité 50% est un bon indicateur d'efficacité de soins et de comparaison entre centres et pays. Le service d'accueil des urgences a pris en charge 28 690 patients parmi lesquels 1 721 ont été hospitalisés. Le ratio hommes/femmes était de 1,75/1. Cinq cent quatorze patients avaient moins de 15 ans. L'âge médian était de 25 ans (3-93). La mortalité globale était de 8,4%. La SL50 était de 63,31% SCT (CI95 56,57-70,02) au-delà de 15 ans et de 72,52% SCT (CI95 61,01-100) en deçà. Les facteurs de risque de mortalité étaient l'âge, le sexe féminin, la surface brûlée et l'inhalation de fumées, paramètres sur lesquels devraient s'appuyer les campagnes de prévention. Les brûlures volontaires sont, dans notre pays, plus fréquentes chez les femmes que chez les hommes.

10.
J Colloid Interface Sci ; 478: 181-7, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27295320

RESUMO

An effective approach for increasing the life cycle of poly ortho aminophenol (POAP) as a p-type conductive polymers is combining conventional conductive polymers and nanomaterials to fabricate hybrid electrodes. In this paper, functionalized graphene oxide (FGO) has first been synthesized using a chemical approach. Hybrid POAP/FGO films have then been fabricated by POAP electropolymerization in the presence of FGO nanoparticles as active electrodes for electrochemical supercapacitors. Based on the atomic scale study results, it seems that H3PO4(-) oxygen atoms and terminal pyridine ring nitrogen atoms play a crucial role in the intramolecular charge and energy transfer in the FGO molecular systems. Theoretical studies, surface and electrochemical analyses have been used for characterization of POAP/FGO composite films. Different electrochemical methods including galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy have been applied to study the system performance. This work introduces new nanocomposite materials for electrochemical redox capacitors with such advantages as the ease of synthesis, high active surface area and stability in an aqueous electrolyte.

11.
Iran J Public Health ; 41(9): 18-24, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23193501

RESUMO

BACKGROUND: Life expectancy at birth as an alternative summary measure of mortality represents number of years which a newborn will be alive based on the current age specific death rates. As it summarizes death rates across all age range in a given population is the most common summary measure of mortality. The aim of this study was to correct death rates for underreport and estimate life expectancy at birth in rural population of Iran in 2008. In addition, this study aimed to assess the Vital Horoscope system's data quality. METHODS: Data were obtained from all Health Houses in Iranian villages in 2008. In order to adjust over 5 years old death rates for underreport, we used Brass Growth Balance method. Since this method is not applicable to under 5 years old, we used child mortality rates projected based on the Iranian Demographic and Health survey 2000 to correct death rates. RESULTS: Adjusted life expectancy at birth for males was 71.5 year and for females was 74.4 year. Completeness of the death data was 88% for males and 79% for females. Adjusted child (under 5) mortality rate by sex in males and females was 25.9 and 23.8 per 1000 live births respectively. Adult mortality for males was 167.2 and 98.3 for females per 1000. CONCLUSION: Data based on Vital Horoscope system are a suitable source to estimate life expectancy and other mortality statistics. Also has an acceptable completeness on death registration. Further studies to investigate accuracy of data from the Vital Horoscope system are suggested.

12.
Acta Trop ; 123(3): 146-53, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22579798

RESUMO

Long lasting insecticide treated nets (LLINs) have been advocated as an effective tool for prevention and control of malaria. Olyset net was the first LLINs which became commercially available and obtained WHO approval. According to the national strategic plan on evaluation of Olyset net, a field trial was conducted to determine the efficacy of these nets against malaria vectors in an endemic area in the southeast of Iran. Fourteen villages with similar topographical and epidemiological situations were selected and randomly assigned to two clusters of the study: Olyset net and untreated net. Distribution of nets was carried out to cover 100% of the population in Olyset net and untreated net cluster. Anopheline mosquitoes were collected monthly using different WHO standard methods in both areas to determine their abundance, feeding pattern and resting behaviour. Human blood index was determined using ELISA test. Additionally, Olyset nets were evaluated for their biological activity using WHO cone bioassay test by susceptible colony of Anopheles stephensi (Beech strain) and then for insecticide residues by employing high performance thin layer chromatography. Malaria incidence was measured by passive and active case detection from all study population. In total 2115 adult anopheline mosquitoes were collected and identified using morphological characters. They comprised of seven species: Anopheles dthali (Liston), A. culicifacies (Giles), A. stephensi (Liston), A. superpictus (Grassi), A.fluviatilis (James), A. moghulensis (Christophers) and A. turkhudi (Liston). A. dthali, A. culicifacies and A. stephensi were most prevalent species in both areas. In the Olyset net study area, there was a significant reduction of 41.1%, 54.4%, 59.39% and 64.1% in the indoor-resting density of A. culicifacies, A. stephensi, A. dthali and A. superpictus, respectively, with an overall reduction of 39.3% in total mosquitoes in comparison with untreated net area. A significant reduction was also observed in human blood index of vector species in the Olyset net villages. Bioefficacy test results of Olyset nets showed that the median knockdown time was 1.48 and 3.25min, while the average mortality rate was 100% and 72.3%±7.07 in baseline and after 1 year of intervention, respectively. The average permethrin content reached to 68.31% (683.1mg/m(2)) of the initial insecticide dose of 937±21.69mg/m(2) (nearly 1000mg/m(2)) at the end of intervention. Malaria incidence was reduced by 96.6% and 64.8% in the village with Olyset nets and in the villages with untreated nets, respectively. During intervention period, there was a reduction of 93.2% in malaria incidence in Olyset net area as compared to the untreated area. This study indicated that Olyset nets have a major impact on malaria vectors and disease burden; therefore it could be recommended as an effective personal protection tool for malaria control in malarious areas.


Assuntos
Doenças Endêmicas , Mosquiteiros Tratados com Inseticida , Inseticidas/farmacologia , Malária/epidemiologia , Malária/prevenção & controle , Controle de Mosquitos/métodos , Permetrina/farmacologia , Animais , Anopheles/classificação , Anopheles/efeitos dos fármacos , Humanos , Incidência , Irã (Geográfico)/epidemiologia
13.
Ann Burns Fire Disasters ; 25(3): 115-20, 2012 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-23466950

RESUMO

We surveyed the epidemiology of the patients in a tertiary burn care centre (the Motahari Burn Hospital) in Tehran in the 4-yr period 2005-2009. Scalding was the major cause of burn injury for patients under the age of 6, while there were many more flame and electrical burns in late childhood. Males were mainly affected (male to female ratio, 1.7:1). Most burns occurred in the summer, probably due to older children's increased outdoor activities during school vacations. Most of the injuries took place in the kitchen. Age was directly related to the higher total body surface area and mortality rate. Explosion of propane gas at home had a high incidence. Length of hospital stay increased in relation to the burn surface area. Infants were found to be at greatest risk for burn injuries, while older children were at higher risk for severe burns. Before arriving at the hospital, 22 patients had received traditional therapy in the home which was not effective and caused some problems. Pre-hospital care by emergency medicine service personnel was complete and effective. 374 patients had positive results for wound culture (42.9%). The most frequent bacteria found in burn wound cultures was coagulase-negative Staphylococcus (66.8%). Blood culture was positive in 12% of the patients with positive burn wound culture and the most frequent bacteria in blood culture was Pseudomonas aeruginosa. The overall mortality rate was 10.6%. Treatment and prevention programmes should target high risk groups. Important criteria include older age, flame burn, presence of inhalation injury, total body surface area burned above 40%, and sepsis.


Nous avons effectué une étude dans un Centre des Brulés de niveau tertiaire (le Motahari Burn Hospital) à Téhéran pendant dans la période de 4 ans 2005-2009 et nous avons constaté que la principale cause des brûlures pour ce qui concerne les patients âgés de moins de 6 ans a été l'ébouillantement. Les enfants plus grands ont été atteints principalement par des brûlures causées par les flammes et par l'électricité. Les mâles ont été principalement affectés (ratio homme-femme, 1.7:1). La plupart des brûlures se sont produites durant l'été, probablement en raison du fait que les enfants plus grands augmentent leurs activités de plein air pendant les vacances scolaires. Les accidents de ce type ont lieu dans la cuisine. L'âge était directement lié au taux de la mortalité plus élevé comme aussi au taux de la surface corporelle totale plus élevée. Les explosions de gaz propane à la maison avaient une incidence élevée. La durée du séjour hospitalier augmentait par rapport à la surface de brûlure. Les nourrissons ont été jugés la catégorie la plus exposée au risque de la brûlure en général, tandis que les enfants plus grands étaient plus à risque pour des brûlures graves. Avant d'arriver à l'hôpital, 22 patients avaient reçu un traitement traditionnel à la maison, qui n'a pas été efficace et a causé quelques problèmes. Les soins d'urgence préhospitaliers fournis par le personnel du service de médecine étaient complets et efficaces. 374 patients ont eu des résultats positifs pour la culture des plaies (42,9%). Les bactéries les plus communs trouvés dans les cultures de plaies de brûlures ont été les Staphylococcus à coagulase négative (66,8%). L'hémoculture était positive dans 12% des patients avec culture des lésions positive, et les bactéries les plus fréquentes observées dans les cultures du sang étaient Pseudomonas aeruginosa. Le taux global de mortalité était de 10,6%. Il faut que les programmes de traitement et de prévention soient orientés vers les groupes à risque élevé. Les critères les plus importants sont l'âge plus avancé, les brûlures par flamme, la présence de lésions par inhalation, la surface corporelle brûlée au-dessus de 40%, et la septicémie.

14.
East Mediterr Health J ; 18(10): 1034-41, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23301358

RESUMO

This study aimed to carry out a malaria situation analysis, species composition and susceptibility levels of the main malaria vector, Anopheles stephensi, to different insecticides in Bashagard. A longitudinal survey was conducted in 2 randomly selected villages in Bashagard. Malaria vectors were sampled by dipping method for the larvae and hand catch, night-biting catch, total catch, and shelter pit collection for the adults. Standard WHO susceptibility tests were used for a variety of insecticides on F1 progeny of An. stephensi reared from wild-caught females. In total, 693 adult anopheline mosquitoes and 839 third and fourth-instar larvae were collected and identified. They comprised 7 species; the most abundant adult and larvae anopheline mosquito was An. dthali (40.7% and 30.5% respectively). An. culicifacies (24.2%) and An. stephensi (16.7%) were the next most common species for adult mosquitoes. An. stephensi was fully susceptible to malathion and pyrethroid insecticides but resistant to DDT and tolerant to dieldrin.


Assuntos
Anopheles/efeitos dos fármacos , Anopheles/parasitologia , Insetos Vetores/efeitos dos fármacos , Insetos Vetores/parasitologia , Inseticidas/farmacologia , Malária/epidemiologia , Animais , Relação Dose-Resposta a Droga , Feminino , Humanos , Resistência a Inseticidas , Irã (Geográfico)/epidemiologia , Larva , Malária/prevenção & controle , Masculino , Técnicas Microbiológicas , Controle de Mosquitos
15.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-118503

RESUMO

This study aimed to carry out a malaria situation analysis, species composition and susceptibility levels of the main malaria vector, Anopheles stephensi, to different insecticides in Bashagard. A longitudinal survey was conducted in 2 randomly selected villages in Bashagard. Malaria vectors were sampled by dipping method for the larvae and hand catch, night-biting catch, total catch, and shelter pit collection for the adults. Standard WHO susceptibility tests were used for a variety of insecticides on F1 progeny of An. stephensi reared from wild-caught females. In total, 693 adult anopheline mosquitoes and 839 third and fourth-instar larvae were collected and identified. They comprised 7 species; the most abundant adult and larvae anopheline mosquito was An. Dthali [40.7% and 30.5% respectively]. An. Culicifacies[24.2%] and An. Stephensi [16.7%] were the next most common species for adult mosquitoes. An. Stephensi was fully susceptible to malathion and pyrethroid insecticides but resistant to DDT and tolerant to dieldrin


Assuntos
Insetos Vetores , Ecologia , Inseticidas , Doenças Endêmicas , Anopheles , Malation , Piretrinas , Culicidae , Malária
16.
Iran J Arthropod Borne Dis ; 4(1): 31-41, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-22808386

RESUMO

BACKGROUND: The aim of this study was that the past five years data were collected to analyze the situation of malaria and health facilities in this area for better understanding malaria problem and to find solutions. METHODS: In this retrospective study data of the last 5 years were obtained from health center of Bandar Abbas, published papers and reports, weather forecasting organization of the city and annual reports of Hormozgan official authorities. An excel databank was created and analysis was conducted using this software. RESULTS: According to the national health system, Bandar Abbas also has referral net work system from periphery to the district health center. The maximum and minimum Annual Parasitic Index (API) were observed in 2005 (1.31) and 2008 (0.17), respectively. The prevalence of cases in villages was more than city, except for 2008. More than 97.6% of indigenous malaria cases were caused by Plasmodium vivax, although P. falciparum, P. ovale and mix infection were also reported. Anopheles stephensi, An. dthali and An. fluviatilis are the main malaria vectors in rural area, while only the first species is distributed in the urban area. CONCLUSION: According to results and many variables including API, Bandar Abbas is divided in two strata. From the situation analysis of Bandar Abbas it is postulated that the main activities of this district could be accuracy of data, and malaria vector control.

17.
IEEE Trans Image Process ; 6(9): 1337-41, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-18283024

RESUMO

A technique for extracting filled-in information in form documents is presented. The transformation that is required to convert a filled-in form to match the master (blank form) is derived using results from projective geometry. Experimental studies with several forms indicate the proposed technique to be accurate and robust.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...