Electrochemical characterization of mixed matrix heterogeneous cation exchange membranes modified by simultaneous using ilmenite-co-iron oxide nanoparticles

Sayed Mohsen Hosseini,Alireza Hamidi,Abdolreza Moghadassi,Sayed Siavash Madaeni 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.3

Mixed matrix heterogeneous cation exchange membranes were prepared by solution casting technique. Ilmenite-co-iron oxide nanoparticle was also employed as inorganic filler additive in membrane fabrication. The effectof the used additives on membrane electrochemical properties was studied. Membrane ion exchange capacity, membranepotential, transport number and selectivity all were improved by use of FeTiO3/Fe3O4 nanoparticles in membranematrix. Utilizing FeTiO3-co-Fe3O4 nanoparticles in the casting solution also led to increase in ionic flux obviously. The modified membranes containing FeTiO3-co-Fe3O4 nanoparticles showed higher transport number, selectivity andionic flux compared to modified membrane containing ilmenite. Electrodialysis experiment in laboratory scale alsoshowed higher cation removal for modified membrane containing FeTiO3-co-Fe3O4 nanoparticles compared to othermodified membranes and pristine ones. Results showed that membrane areal electrical resistance declined sharply byuse of FeTiO3-co-Fe3O4 nanoparticles in membrane matrix. Moreover, modified membrane containing ilmenite showedlower electrical resistance compared to others. Results showed that oxidative stability of membranes was decreasedslightly by use of FeTiO3/Fe3O4 nanoparticles in membrane matrix. The results revealed that modified membranes inthis study are comparable with that of other commercial ones.

Preparation and electrochemical characterization of polyvinylchloride/ FeTiO3-co-Fe3O4 nanoparticles mixed matrix ion exchange membranes: Investigation of concentration and pH effects

Sayed Mohsen Hosseini,Alireza Hamidi,Abdolreza Moghadassi,Fahime Parvizian,Sayed Siavash Madaeni 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.9

Polyvinyl chloride based/FeTiO3-co-Fe3O4 nanoparticles mixed matrix heterogeneous cation exchange membranes were prepared by solution casting technique. The effect of using filler additives in casting solution and also electrolyte concentration and pH on electrochemical properties of membrane was studied. Membrane potential, transport number and selectivity were improved by using FeTiO3/Fe3O4 nanoparticles in membrane matrix. Utilizing FeTiO3/ Fe3O4 nanoparticles in membrane matrix also led to improvement of membrane ionic flux from 2.95*10−5 to 4.15*10−5 (mol/m2·s) obviously. Similar trend was also found for membrane electrical conductivity. Moreover, the transport number, selectivity and membrane electrical conductivity were enhanced by increase of electrolyte concentration. Prepared membranes exhibited higher transport number/selectivity at pH 7 compared to other pH values. Obtained results showed that the membrane electrical resistance decreased initially by increase of electrolyte pH sharply and then began to increase. Membranes exhibited lower selectivity for bivalent ions compared to monovalent type. Modified membranes containing FeTiO3/Fe3O4 nanoparticles showed more appropriate electrochemical properties compared to other prepared membranes.

Effect of timing of morphine administration during propofol - remifentanil anesthesia on the requirements of post-operative analgesia

Farid Zand,Afshin Amini,Seyed Alireza Hamidi 대한마취통증의학회 2012 Korean Journal of Anesthesiology Vol.63 No.3

Background: An important concern of intra-operative infusion of remifentanil is the possible development of acute opioid tolerance, which manifests as an increased postoperative analgesia requirement. We have examined the effect of the timing of intra operative morphine administration on the need for morphine consumption for pain control during the first 24 hours after operation. Methods: Sixty adult patients scheduled for elective open unilateral nephrolithotomy surgery were recruited for this prospective randomized double-blind study. Anesthesia was induced with 0.03 mg/kg midazolam, 1 μg/kg remifentanil, and 1.5-2 mg/kg propofol. Anesthesia was maintained with 100 μg/kg/min propofol, and 0.25 μg/kg/min remifentanil. Both groups received 0.1 mg/kg morphine intravenously at 2 different times; in the first group (group E) immediately after intubation and in the second group (group L) 20-30 min before the anticipated end of operation. Results: There was no difference in pain scores at awakening, the amount of morphine given to the 2 groups for pain control, or the time to discharge from PACU between the 2 groups. The pain scores at admission to ward and at every 4 hours thereafter, until 24 hours, were not significantly different between the 2 groups. The cumulative amount of the first 24 hours morphine consumption in the ward in E group was 28.2 ± 20.1 mg and 26.5 ± 15 mg in L group, respectively (P = 0.71). Conclusions: Early intra-operative administration of morphine compared to that of morphine in the end of surgery did not affect postoperative morphine consumption and pain scores during the first 24 hours after surgery for open nephrolithotomy. Newer pharmacologic interventions for prevention of acute tolerance of opioids seems rational (Clinical trial registration No. ACTRN: 12609000570280). Background: An important concern of intra-operative infusion of remifentanil is the possible development of acute opioid tolerance, which manifests as an increased postoperative analgesia requirement. We have examined the effect of the timing of intra operative morphine administration on the need for morphine consumption for pain control during the first 24 hours after operation. Methods: Sixty adult patients scheduled for elective open unilateral nephrolithotomy surgery were recruited for this prospective randomized double-blind study. Anesthesia was induced with 0.03 mg/kg midazolam, 1 μg/kg remifentanil, and 1.5-2 mg/kg propofol. Anesthesia was maintained with 100 μg/kg/min propofol, and 0.25 μg/kg/min remifentanil. Both groups received 0.1 mg/kg morphine intravenously at 2 different times; in the first group (group E) immediately after intubation and in the second group (group L) 20-30 min before the anticipated end of operation. Results: There was no difference in pain scores at awakening, the amount of morphine given to the 2 groups for pain control, or the time to discharge from PACU between the 2 groups. The pain scores at admission to ward and at every 4 hours thereafter, until 24 hours, were not significantly different between the 2 groups. The cumulative amount of the first 24 hours morphine consumption in the ward in E group was 28.2 ± 20.1 mg and 26.5 ± 15 mg in L group, respectively (P = 0.71). Conclusions: Early intra-operative administration of morphine compared to that of morphine in the end of surgery did not affect postoperative morphine consumption and pain scores during the first 24 hours after surgery for open nephrolithotomy. Newer pharmacologic interventions for prevention of acute tolerance of opioids seems rational (Clinical trial registration No. ACTRN: 12609000570280).

Evaluation of the Quality of Occupational Health and Safety Management Systems Based on Key Performance Indicators in Certified Organizations

Mohammadfam, Iraj,Kamalinia, Mojtaba,Momeni, Mansour,Golmohammadi, Rostam,Hamidi, Yadollah,Soltanian, Alireza Occupational Safety and Health Research Institute 2017 Safety and health at work Vol.8 No.2

Background: Occupational Health and Safety Management Systems are becoming more widespread in organizations. Consequently, their effectiveness has become a core topic for researchers. This paper evaluates the performance of the Occupational Health and Safety Assessment Series 18001 specification in certified companies in Iran. Methods: The evaluation is based on a comparison of specific criteria and indictors related to occupational health and safety management practices in three certified and three noncertified companies. Results: Findings indicate that the performance of certified companies with respect to occupational health and safety management practices is significantly better than that of noncertified companies. Conclusion: Occupational Health and Safety Assessment Series 18001-certified companies have a better level of occupational health and safety; this supports the argument that Occupational Health and Safety Management Systems play an important strategic role in health and safety in the workplace.

Evaluation of the Quality of Occupational Health and Safety Management Systems Based on Key Performance Indicators in Certified Organizations

Iraj Mohammadfam,Mojtaba Kamalinia,Mansour Momeni,Rostam Golmohammadi,Yadollah Hamidi,Alireza Soltanian 한국산업안전보건공단 산업안전보건연구원 2017 Safety and health at work Vol.8 No.2

Background Occupational Health and Safety Management Systems are becoming more widespread in organizations. Consequently, their effectiveness has become a core topic for researchers. This paper evaluates the performance of the Occupational Health and Safety Assessment Series 18001 specification in certified companies in Iran. Methods The evaluation is based on a comparison of specific criteria and indictors related to occupational health and safety management practices in three certified and three noncertified companies. Results Findings indicate that the performance of certified companies with respect to occupational health and safety management practices is significantly better than that of noncertified companies. Conclusion Occupational Health and Safety Assessment Series 18001-certified companies have a better level of occupational health and safety; this supports the argument that Occupational Health and Safety Management Systems play an important strategic role in health and safety in the workplace.