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The main objective of this work is to provide a better understanding of the warm-up phase of high-intensity discharge lamps. As an example of application, we chose the high-pressure mercury lamp. Based on two-dimensional fluid model parameters, such as the electric current, the length and the diameter of the burner are modified and the effect of the convective transport is studied. This allows us to obtain a thorough understanding of the physics of these lamps in their transitory phase. The simulation of the warm-up phase is a must for the proper predictions of the lamp behavior and can be conducted by solving the energy balance, momentum, and Laplace’s equations for the plasma, using the frame of the local thermodynamic equilibrium coupled with the energy balance of the wall. [ABSTRACT FROM AUTHOR]

An electronic pulsed power supplier for High Intensity Discharge (HID) lamps is presented in this paper. The pulsed power supplier is obtained from the integration of a two current source AC/DC converter and a full-bridge inverter. The electronic supply provides to the lamp a different current form excitation (crenels and superposition of pulses). The lamp is represented in a model of simulation by its conductance model and coupled to its electronic power supply. Finally, some experimental results from a laboratory prototype are shown and compared with simulation. The general objective of this work consists in studying the effect of a current pulsed power supply on the electric and photometric behaviour of the discharge lamps, intended in particular for photochemistry. [ABSTRACT FROM AUTHOR]

Di(2-ethylhexyl) dithiophosphoric acid (D2EHDTPA) was examined for cadmium removal from phosphoric acid solutions. High extraction performance was achieved. By means of slope and saturation methods, the stoichiometry of the complex was postulated. Both methods indicated the presence of anhydrous CdR2 as being the metallic extracted complex, HR denoting the D2EHDTPA molecule. The stripping of cadmium from the organic phase was ensured by aqueous solutions of HCl; quantitative stripping was achieved with either HCl (4 M) or an HCl-NaCl mixture. [ABSTRACT FROM AUTHOR]

This paper deals with the solvent extraction of silver from thiourea leaching Ag ore liquors as an alternative to the traditional process involving cyanide. The investigation of the extraction mechanism of silver from acidic thiourea solution had not been clearly established to date. The extraction behavior of silver using di(2-ethylhexyl)dithiophosphoric acid (D2EHDTPA) and di(2,4,4-trimethylpentyl) thiophosphinic acid (CYANEX 302) was studied. The effect of various parameters such as concentrations of metal, mineral acid, thiourea, and extractant has been investigated. The extracted complexes have been identified through a slope method analysis as AgX(HX)5 for CYANEX 302 and AgX for D2EHDTPA, where HX denotes the extractant. Moreover, complete stripping was ensured with a mixture of NH4SCN and H2SO4. In addition we showed that a first step of extraction with D2EHPA or CYANEX 272 results in the preferential separation of Fe(III) from the Ag(I) leach solution. [ABSTRACT FROM AUTHOR]

The influence of a pulsed-current power supply on the electrical properties and the spectral radiant flux emitted by a germicidal ultraviolet (UV) lamp has been investigated, both experimentally and theoretically. A self-consistent collisional–radiative model has been developed and used to model the temporal behaviour of the plasma characteristics of the lamp operated in the pulsed mode. The model includes elastic and inelastic processes as well as ambipolar diffusion. The macroscopic properties of the plasma, including the electron temperature, electric fields, radiation and energy transfer due to various collisional processes, have been considered. To evaluate the energy emitted in the UV bandwidth, a photometric system composed of an integrating cylinder, a UV radiometer, a spectrograph and a charge-coupled device camera is mounted. This study provides a framework for the design of a pulsed-current power supply, which permits the generation of a single pulse or multiple pulses superimposed on a low-frequency square wave. [ABSTRACT FROM AUTHOR]

The extraction of nickel(II) from acidic aqueous solutions using a mixture of 2-ethylhexanal oxime (EHO) and bis(2-ethylhexyl) phosphoric acid (D2EHPA) in dodecane has been investigated as a function of total concentrations of each extractant, metal and protons. The aqueous salt concentration is proved to have no significant effect for both ammonium nitrate and chloride. The extracted organic complex is then Ni(Ox)2(HOx)2(HA)2 or Ni(HOx)4A2, where HA denotes the organo-phosphoric acid and HOx the oxime. A complementary isomolecular study has been achieved to confirm this stoichiometry. As aggregation plays a crucial role in extraction phenomenon, Vapor Pressure Osmometry (VPO) measurements have been carried out in order to determine the aggregation numbers for either the separate extractants or their mixtures. The bis(2-ethylhexyl) phosphoric acid is mainly under dimer and trimer forms, while no mixed aggregation is observed. [ABSTRACT FROM AUTHOR]

The extraction of nickel(II) from various aqueous solutions by 2-ethylhexanal oxime (EHO) in dodecane has been studied as a function of total concentrations of extractant, metal and salts and of the equilibrium pH. In the absence of salts, as well as in the presence of ammonium and sodium nitrates, the extracted complex is: Ni(EHO)5(H2O). In the complexing chloride medium, two different species exist, depending on acidity: for pH lower than 4, Ni(EHO)3 Cl2(H2O) and pH above 4, Ni(EHO)4Cl(H2O). 2-ethylhexanal oxime forms multimers. In dodecane The knowledge of these association degrees is very important when EHO is used as an extracting reagent. The EHO aggregation numbers have been determined by the VPO method (Vapour Pressure Osmometry) at three temperatures (24, 29 and 34°C) in a wide concentration range (0.03–0.77 mol.kg-1). EHO forms monomers, dimers and trimers. The formation constants of these aggregates have been estimated by numerical analysis. [ABSTRACT FROM AUTHOR]

Introduction: Acutemarital psychosis is an acute psychotic episode occurring in a particular context which is marriage. In fact, marriage represents an event with a very important emotional load especially in theArab-Muslim culture. This event can, in some people, induce a relapse of certain psychiatric disorders, particularly psychotic ones. We propose in this work to report two clinical observations concerning two brothers who both presented, a few years apart, an acute nuptial psychosis with two different evolutions. Objectives: Studing the characteristics of nuptial psychotic episode in a one family and the different evolution of each one. Methods: Reporting two clinical cases of two brothers who represented both acute psychotic episode in a nuptial context with different evolution. Results: The two patients are brothers with common psychiatric background which is their mother treated for chronic psychotic disorder. They were hospitalized in our psychiatric service for acute psychotic episode occuring in a nuptial context with chronic evolution for the first one and a partial recovery for the second one. Conclusions: Marriage represents an event with a very important emotional load especially in the Arab-Muslim culture. In thiscontext, acute psychotic episode can occur with different evolution for patients predisposed. Studing socio-cultral circumstances related to psychotic episode can help mental health professional to improve the quality of health care service. [ABSTRACT FROM AUTHOR]

Background: Public education efforts to address and reduce potential harms from cannabis use in Arab countries are either slow or inexistent, and do not follow the steadily increasing trends of cannabis use in Arab youth. Several decades of research on substance use, it can be suggested that being aware of, and knowing about, psychosis risk related to cannabis can at least limit the consumption of the substance. Motivated by a lack of measures specifically designed to measure literacy about cannabis-related psychosis risk in younger populations, and based on an extensive literature review, we aimed to create and validate a new self-report scale to assess the construct, the Cannabis-related Psychosis Risk Literacy Scale (CPRL), in the Arabic language., Method: A cross-sectional study was carried-out during the period from September 2022 to June 2023, enrolling 1855 university students (mean age of 23.26 ± 4.96, 75.6% females) from three Arab countries (Egypt, Kuwait and Tunisia)., Results: Starting from an initial pool of 20 items, both Exploratory Factor Analysis and Confirmatory Factor Analysis suggested that the remaining 8 items loaded into a single factor. The scale demonstrated good internal consistency, with both McDonald omega and Cronbach's alpha values exceeding 0.7 (omega = 0.85 / alpha = 0.85). The CPRL showed measurement invariance across gender and country at the configural, metric, and scalar levels. Concurrent validity of the CPRL was established by correlations with less favourable attitudes towards cannabis (r = -.14; p <.001). In addition, higher literacy levels were found in students who never used cannabis compared to lifetime users (4.18 ± 1.55 vs. 3.44 ± 1.20, t(1853) = 8.152, p <.001)., Conclusion: The newly developed CPRL scale offers a valid and reliable instrument for assessing and better understanding literacy about cannabis-related psychosis risk among Arabic-speaking young adults. We believe that this new scale is suitable as a screening tool of literacy, as an instrument for measuring the effect of public education interventions aimed at promoting cannabis-related psychosis risk literacy among young people, and as a research tool to facilitate future studies on the topic with a wider application., (© 2024. The Author(s).)

Background: Even though not all cyber bullies or victims think of (or consider) suicide, they clearly appear to be at an increased risk. One possible strategy to reduce suicide risk is to decrease cyberbullying occurrence; but this approach has its limitations, as it is certainly an illusion to believe that cyberbullying could be controlled or eliminated in a digitalized world. Another alternative and interesting strategy is to consider mediating factors that may indirectly affect suicidality. To this end, our purpose was to test the hypothesis that positive and negative psychotic experiences (PEs) mediate the relationship from cyberbullying perpetration/victimization to suicidal ideation (SI)., Method: The study followed a cross-sectional design, and was conducted during the period from June to September 2022. A total of 3103 healthy community participants from Lebanon were included (mean age 21.73 ± 3.80 years, 63.6% females)., Results: After adjusting over potential confounders, mediation analysis models showed that both positive and negative PEs partially mediated the associations between cyberbullying victimization/perpetration and SI. Higher cyberbullying perpetration and victimization were significantly associated with greater positive and negative PEs; more severe positive and negative PEs were significantly associated with higher levels of SI. Higher cyberbullying victimization and perpetration were significantly and directly associated with higher levels of SI., Conclusion: In light of our preliminary findings, there appears to be an urgent need for a new focus on carefully assessing and addressing attenuated psychotic symptoms in healthy individuals engaged in cyberbullying either as victims or bullies and who present with SI. It is important that school counselors and decision-makers consider a holistic approach taking into account both external/environmental (bullying) and internal/individual (PEs) factors in their suicide prevention programs. Future longitudinal research in larger samples are still required to confirm our findings and further elucidate the mechanisms underlying the relationship between cyberbullying and suicide., (© 2024. The Author(s).)

Background: Most of the young individuals with problem gambling (PG) or psychotic experiences (PEs) are less prone to seek medical help. Therefore, community-based studies investigating the relationship between these entities in non-clinical young people across a continuum of severity are warranted. To this end, the present study proposes to advance knowledge on the mechanisms that potentially underlie the association between PG and PEs, by examining the role of a potential moderator, i.e. alexithymia, in this relationship., Methods: A total of 399 participants enrolled in this study (mean age = 21.58 ± 3.20 years) participated in an online cross-sectional survey. The South Oaks Gambling Screen (SOGS), the Prodromal Questionnaire-Brief (PQ-B), and the Toronto alexithymia scale (TAS-20) were used., Results: Thirty-three (8.3%) participants had problem-gambling, whereas 13 (3.3%) were probable pathological gamblers. Moderation analysis results adjusted over confounders (age, household crowding index, marital status, personal history of mental disorder, other illegal drug use) showed that the interaction PG by alexithymia (p = .018) was significantly associated with PEs scores. At moderate (Beta = 1.93) and high (Beta = 3.38) levels of alexithymia, more PG was significantly associated with more PEs scores., Conclusion: Findings suggest that GP may have a different impact on PEs depending on the individual's level of alexithymia. As such, both alexithymia and gambling behavior should be considered in the clinical assessment of young people who present with PEs, which can help in implementing more tailored and individualized treatment plans., (© 2024. The Author(s).)

Saffron " Crocus sativus " is a plant of the Iridaceae family. Its therapeutic virtues have been known since antiquity; it is used in traditional medicine and culinary preparations. It is also known for its use in cosmetics because of its beneficial pharmacological activities for human skin. In particular, saffron tepals are the main by-product of saffron processing; they contain several bioactive compounds such as mineral agents, anthocyanins, monoterpenoids, carotenoids, flavonoids, and flavonols (kaempferol). This review aims to describe the different properties of saffron flower tepals, including their botanical characteristics, phytochemical composition, biological activities, and cosmetology and perfumery uses.

Background: The majority of research attention has been devoted to the link between religiosity and suicide risk, and a considerable amount of studies has been carried out on how stigma impacts individuals with mental health problems of different kinds. However, the interplay between religiosity, suicide literacy and suicide stigma has seldom been empirically researched, especially quantitatively. We sought through this study to redress the imbalance of research attention by examining the relationship between religiosity and suicide stigma; and the indirect and moderating effects of suicide literacy on this relationship., Method: A cross-sectional web-based survey was conducted among Arab-Muslim adults originating from four Arab countries (Egypt: N  = 1029, Kuwait: N  = 2182, Lebanon N  = 781, Tunisia N  = 2343; Total sample: N  = 6335). The outcome measures included the Arabic Religiosity Scale which taps into variation in the degree of religiosity, the Stigma of Suicide Scale-short form to the solicit degree of stigma related to suicide, and the Literacy of Suicide Scale explores knowledge and understanding of suicide., Results: Our Mediation analyses findings showed that literacy of suicide partially mediated the association between religiosity and stigmatizing attitude toward suicide. Higher religiosity was significantly associated with less literacy of suicide; higher literacy of suicide was significantly associated with less stigma of suicide. Finally, higher religiosity was directly and significantly associated with more stigmatization attitude toward suicide., Conclusion: We contribute the literature by showing, for the first time, that suicide literacy plays a mediating role in the association between religiosity and suicide stigma in a sample of Arab-Muslim community adults. This preliminarily suggests that the effects of religiosity on suicide stigma can be modifiable through improving suicide literacy. This implies that interventions targeting highly religious individuals should pay dual attention to increasing suicide literacy and lowering suicide stigma., Competing Interests: Conflict of interestNone.

Background: Determining the potential barriers responsible for delaying access to care, and elucidating pathways to early intervention should be a priority, especially in Arab countries where mental health resources are limited. To the best of our knowledge, no previous studies have examined the relationship between religiosity, stigma and help-seeking in an Arab Muslim cultural background. Hence, we propose in the present study to test the moderating role of stigma toward mental illness in the relationship between religiosity and help-seeking attitudes among Muslim community people living in different Arab countries., Method: The current survey is part of a large-scale multinational collaborative project (StIgma of Mental Problems in Arab CounTries [The IMPACT Project]). We carried-out a web-based cross-sectional, and multi-country study between June and November 2021. The final sample comprised 9782 Arab Muslim participants (mean age 29.67 ± 10.80 years, 77.1% females)., Results: Bivariate analyses showed that less stigmatizing attitudes toward mental illness and higher religiosity levels were significantly associated with more favorable help-seeking attitudes. Moderation analyses revealed that the interaction religiosity by mental illness stigma was significantly associated with help-seeking attitudes (Beta = .005; p < .001); at low and moderate levels of stigma, higher religiosity was significantly associated with more favorable help-seeking attitudes., Conclusion: Our findings preliminarily suggest that mental illness stigma is a modifiable individual factor that seems to strengthen the direct positive effect of religiosity on help-seeking attitudes. This provides potential insights on possible anti-stigma interventions that might help overcome reluctance to counseling in highly religious Arab Muslim communities., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Background: While expansive research has accumulated concerning the association between traditional, face-to-face peer victimization and psychosis, a paucity of empirical research has been undertaken so far to investigate these associations with experiences of new and evolving ways of victimization through the digital world. Exploring these associations is highly relevant and timely, given that emerging adults are heavy users of digital technologies, highly exposed to online risks, and are at the peak age of onset of psychosis. This study aimed to test the hypothesis that psychological distress and insomnia symptoms have a significant indirect mediating effect on the association between cyber-victimization and self-reported positive psychotic experiences (SRPEs) in a binational sample of Tunisian and Lebanese community adults., Method: The total sample was composed of 3766 participants; 3103 were from Lebanon (Mean age: 21.73 ± 3.80 years, 63.6% females) and 663 from Tunisia (Mean age: 26.32 ± 4.86 years, 59.9% females). Online anonymous self-report questionnaires were administered to all participants., Results: Higher SRPEs were found in Lebanese participants compared to Tunisians, in single participants compared to married ones, in those with a university level of education compared to secondary or less, in those who live in rural areas compared to urban, in those who do not smoke, do not drink alcohol and do not use marijuana or any other illegal drug. Furthermore, more cyber-victimization, a higher insomnia severity and psychological distress were significantly associated with higher SRPEs. After adjusting for potential confounders, mediation analysis demonstrated that higher cyber-victimization was significantly associated with more insomnia severity/psychological distress; which were, in turn, significantly associated with greater SRPEs. Finally, more cyber-victimization was significantly and directly associated with more positive dimension., Conclusion: Identifying insomnia and distress as mediators could provide novel insight for psychosis prevention efforts and intervention targets for cyber-victimized individuals prone to experience subclinical psychotic symptoms., (© 2023. The Author(s).)

Background: The main goal of the present study was to examine the characteristics of schizotypal traits and their correlations with genetic (i.e., family history of mental illness), demographic (i.e., age, sex), environmental (e.g., income, urbanicity, tobacco/alcohol/cannabis use), and psychological (i.e., personal history of mental illness other than psychosis) factors in Tunisian high-school and university students. Our secondary goal was to contribute the literature by examining the factor structure and factorial invariance of the Arabic Schizotypal Personality Questionnaire (SPQ) across sex and age (adolescents [12-18 years] vs. young adults [18-35 years]) groups., Method: This was a cross-sectional study involving 3166 students: 1160 (36.6%) high-school students (53.0% females, aged 14.9 ± 1.8); and 2006 (63.4%) university students (63.9% females, aged 21.8 ± 2.3). All students were asked to complete a paper-and-pencil self-administered questionnaire containing sociodemographic characteristics as well as the Arabic version of the SPQ., Results: The total sample yielded total SPQ scores of 24.1 ± 16.6 out of 74. The SPQ yielded good composite reliability as attested by McDonald's omega values ranging from .68 to .80 for all nine subscales. Confirmatory Factor Analysis indicated that fit of the 9-factor model of SPQ scores was acceptable. This model is invariant (at the configural, metric and structural levels) across sex and age. Except for "Odd or eccentric behavior", all schizotypy features were significantly higher among female students compared to males. Multivariable analyses showed that female sex, being a university student, lowest family incomes, tobacco use, and having a personal history of psychiatric illness were significantly associated with higher positive, negative and disorganized schizotypy subscales scores., Conclusion: Future research still needs to confirm our findings and investigate the contribution of the identified factors in the development of clinical psychosis. We can also conclude that the Arabic SPQ is appropriate for measuring and comparing schizotypy across age and sex in clinical and research settings. These findings are highly relevant and essential for ensuring the clinical utility and applicability of the SPQ in cross-cultural research., (© 2023. The Author(s).)

Background: There is evidence that culture deeply affects beliefs about mental illnesses' causes, treatment, and help-seeking. We aimed to explore and compare knowledge, attitudes toward mental illness and help-seeking, causal attributions, and help-seeking recommendations for mental illnesses across various Arab countries and investigate factors related to attitudes toward help-seeking., Methods: We carried out a multinational cross-sectional study using online self-administered surveys in the Arabic language from June to November 2021 across 16 Arab countries among participants from the general public., Results: More than one in four individuals exhibited stigmatizing attitudes towards mental illness (26.5%), had poor knowledge (31.7%), and hold negative attitudes toward help-seeking (28.0%). ANOVA tests revealed a significant difference between countries regarding attitudes (F = 194.8, p < .001), knowledge (F = 88.7, p < .001), and help-seeking attitudes (F = 32.4, p < .001). Three multivariate regression analysis models were performed for overall sample, as well as Palestinian and Sudanese samples that displayed the lowest and highest ATSPPH-SF scores, respectively. In the overall sample, being female, older, having higher knowledge and more positive attitudes toward mental illness, and endorsing biomedical and psychosocial causations were associated with more favorable help-seeking attitudes; whereas having a family psychiatric history and endorsing religious/supernatural causations were associated with more negative help-seeking attitudes. The same results have been found in the Palestinian sample, while only stigma dimensions helped predict help-seeking attitudes in Sudanese participants., Conclusion: Interventions aiming at improving help-seeking attitudes and behaviors and promoting early access to care need to be culturally tailored, and congruent with public beliefs about mental illnesses and their causations., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)

The present study followed the newly hypothesized "suicidal drive for psychosis" suggesting that psychosis may be consequential to suicidal ideation (SI) and behavior and attempted to explain parts of the pathway between these variables. To this end, we aimed to test whether problematic smartphone use (PSU) has an indirect mediating effect in the cross-sectional relationship between SI and positive psychotic experiences (PEs). Lebanese community young adults ( N =4158; 64.4% females; mean age 21.91±3.79) have been invited to participate to a cross-sectional, web-based study in the period from June to September 2022. After adjusting for potential confounders (i.e., the living situation, marital status, household crowding index, economic pressure, cannabis use, other drugs use, and past history of mental illness other than psychosis), we found that higher levels of suicidal ideation was significantly associated with greater PSU, which was also positively and significantly associated with more positive PEs. Finally, greater suicidal ideation was significantly and directly associated with more positive PEs. Our findings suggest that SPU may be regarded as a potential target for prevention and intervention in psychosis. Clinicians, educators, and school administrators ought to give greater attention to PSU among vulnerable young people who present with SI., Competing Interests: Conflict of InterestThe authors do not have conflicts of interest to disclose., (© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

The goal of this research is to see how the amount and particle size of calcium carbonate (CaCO 3 ) used in the foamed layer in use for PVC-coated textiles affects the thermal properties of the material. Two different particle sizes were used at various concentrations. The impact of different CaCO 3 loadings and particle sizes on the PVC foamed layer's thermal properties were examined. Thermogravimetry (TGA and DTG) and differential scanning calorimetry (DSC) measurements were utilized to investigate the thermal properties of the PVC foamed layer and the samples have been also characterized by FTIR spectroscopy. According to the findings, the thermal stability of the foamed layer was improved with the addition of calcium carbonate. Through the higher surface area between the filler and the PVC matrix, smaller particle sizes have produced the best results. The PVC foamed layer shows also changes in FTIR spectra after adding CaCO 3 , and the intensity of peaks increases with decreasing CaCO 3 particle size., (© TÜBİTAK.)

Bio-based organic acids are promising renewable carbon sources for the chemical industry. However energy-consuming purification processes are used, like distillation or crystallization, to reach high purities required in some applications. That is why preparative chromatography was studied as an alternative separation technique. In a previous work dealing with the purification of lactic, succinic and citric acids, the Langmuir model was insufficient to explain the elution profiles obtained with a strong anionic resin. Consequently the Langmuir model was coupled with a usual ion-exchange model to take into account the retention of their conjugate bases (<2%), which are commonly neglected at low pH (<1.5). Elution simulations with both uptake mechanisms fitted very well with experimental pulse tests. Only two parameters were optimized (equilibrium constant of acid uptake and ion-exchange selectivity coefficient of conjugate base) and their value were coherent with experimental and resin suppliers' data. These results confirmed that the singular tailing and apparent delay observed with succinic and citric acids can be explained by the high affinity of succinate and citrate for resin cationic sites. The model was implemented in a preparative chromatography simulation program in order to optimize operating parameters of our pilot-scale ISMB unit (Improved Simulated Moving Bed). The comparison with experimental ISMB profiles was conclusive., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The accumulation (internal and superficial distribution) of magnesium ions (Mg(2+)) by the green freshwater microalga Chlorella vulgaris (C. vulgaris) was investigated under autotrophic culture in a stirred photobioreactor. The concentrations of the three forms of Mg(2+) (dissolved, extracellular, and intracellular) were determined with atomic absorption spectroscopy during the course of C. vulgaris growth. The proportions of adsorbed (extracellular) and absorbed (intracellular) Mg(2+) were quantified. The concentration of the most important pigment in algal cells, chlorophyll a, increased over time in proportion to the increase in the biomass concentration, indicating a constant chlorophyll/biomass ratio during the linear growth phase. The mean-average rate of Mg(2+) uptake by C. vulgaris grown in a culture medium starting with 16 mg/l of Mg(2+) concentration was measured. A clear relationship between the biomass concentration and the proportion of the Mg(2+) removal from the medium was observed. Of the total Mg(2+) present in the culture medium, 18% was adsorbed on the cell wall and 51% was absorbed by the biomass by the end of the experiment (765 h). Overall, 69% of the initial Mg(2+) were found to be removed from the medium. This study supported the kinetic model based on a reversible first-order reaction for Mg(2+) bioaccumulation in C. vulgaris, which was consistent with the experimental data.

Aspirin overdose could lead to intoxication, with the clinical manifestations of vomit, pulmonary edema and severe dyspnea. Stomach washing, emetics and activated charcoal are the common treatments with a limited efficiency for the intoxication. In this study, an active emulsion for aspirin intoxication was prepared with the detoxifying efficiency of 100% in less than 15 min, with the conditions of dodecane used as the oil phase, 8% Abil EM90 as the surfactant and 0.1 mol/L sodium hydroxide as the inner aqueous phase in a volume ratio of 2 between internal aqueous phase and the oil phase., (Copyright © 2012. Published by Elsevier B.V.)

The scale-up of nanoemulsions (NEs) produced by emulsification and solvent diffusion process was successfully achieved in the present work. Up to 1500 mL of NEs were produced with olive oil, castor oil, almond oil, or Arlamol™ E by using a Y-shaped mixer device. NE droplet sizes were significantly modulated from 290 to 185 nm by changing the process parameters without modification of the formulation composition. Smaller NE droplet sizes were obtained by (1) decreasing the internal diameter of the Y-mixer from 5 to 0.8 mm, (2) increasing the flow rates of the organic and the aqueous phases upon mixing, and (3) increasing the temperature of the experiment from 5°C to 40°C. All the results of NE diameters (d(sc) ) expressed as a function of the Reynolds number (Re) and the shear rate inside the Y-mixer (\documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\dot \gamma$\end{document}) showed the existence of typical power-law relationships: d(sc) = 10(2.82) Re(- 0.14) and \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$d&#95;{{\rm sc}} = 10^{2.60} \dot \gamma ^{- 0.06}$\end{document}, respectively. The existence of these power-laws for NE formation by emulsification and solvent diffusion process has never been reported in the literature yet and constitutes a new finding in this work. We definitely proved that the high turbulences created upon NE formation are the most important parameter allowing to decrease droplet size., (Copyright © 2012 Wiley-Liss, Inc.)

The study of radionuclides speciation requires accurate evaluation of stability constants, which can be achieved by CE-ICPMS. We have previously described a method for 1:1 metal complexes stability constants determination. In this paper, we present its extension to the case of successive complexations and its application to uranyl-oxalate and lanthanum-oxalate systems. Several significant steps are discussed: analytical conditions choice, mathematical treatment by non-linear regression, ligand concentration and ionic strength corrections. The following values were obtained: at infinite dilution, log(beta(1) degrees (UO(2)Oxa))=6.93+/-0.05, log(beta(2) degrees (UO(2)(Oxa)(2) (2-)))=11.92+/-0.43 and log(beta(3) degrees (UO(2)(Oxa)(3) (4-)))=15.11+/-0.12; log(beta(1) degrees (LaOxa(+)))=5.90+/-0.07, log(beta(2) degrees (La(Oxa)(2) (-)))=9.18+/-0.19 and log(beta(3) degrees (La(Oxa)(3) (3-)))=9.81+/-0.33. These values are in good agreement with the literature data, even though we suggest the existence of a new lanthanum-oxalate complex: La(Oxa)(3) (3-). This study confirms the suitability of CE-ICPMS for complexation studies.

Nuclear energy development has raised new issues like radionuclides biogeochemistry. The modelling of their biochemical properties involves the accurate determination of thermodynamical data, like stability constants. This can be achieved by using hyphenated capillary electrophoresis (CE)-ICPMS and the method was applied successfully on 1:1 lanthanum-oxalate and uranyl-oxalate complexes. Several significant steps are discussed: choice of analytical conditions, electrophoretic mobility calculation, mathematical treatment of experimental data by using linear regressions, ligand concentration and ionic strength corrections. The following values were obtained with a good precision for lanthanum-oxalate and uranyl-oxalate complexes: log(K degrees (LaOxa(+)))=6.10+/-0.10 and log(K degrees (UO(2)Oxa))=6.40+/-0.30, respectively, at infinite dilution. These values are consistent with the literature data, showing CE-ICPMS potential for metal complexes stability constants determination.

The release of tetradecane from a multiple emulsion of the type tetradecane/water/hexadecane was studied experimentally using the differential scanning calorimetry technique. The kinetics of the tetradecane release was measured for three formulations containing different concentrations of hydrophilic surfactant (2%, 4%, and 7%). A new mass transfer model derived from the shrinking core model was developed. The values of the model parameters deduced from the least-squares fittings led to the determination of the tetradecane diffusivity. Thus, the preponderant mechanism of mass transfer was proved to be micellar diffusion and not molecular diffusion. This conclusion was confirmed by considering the effect of the change in the hydrophilic surfactant concentration.