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Receiving fungicides on basis of bischofite / Получение фунгицидов на основе минерала бишофита  [cached]
Filimonova N.A. / Филимонова Наталья Алексеевна,Fomichev V.T. / Фомичев Валерий Тарасович
Internet-Vestnik VolgGASU , 2006,
Abstract: Prospective technology of receiving fungicide by means of electrolysis from bischofite solution for struggle against pathogenic fungi in construction and agriculture is studied. / Рассмотрена перспективная технология получения фунгицидов методом электролиза из растворов бишофита для борьбы с патогенными грибами в строительстве и сельском хозяйстве.
Extractive process for preparing high purity magnesium chloride hexahydrate  [PDF]
Fezei Radouanne,Hammi Halim,M’nif Adel
Chemical Industry and Chemical Engineering Quarterly , 2012, DOI: 10.2298/ciceq110815049f
Abstract: This paper refers a method for the preparation of magnesium chloride hexahydrate (bischofite) from Sebkha el Melah of Zarzis Tunisian natural brine. It is a five-stage process essentially based on crystallization by isothermal evaporation and chemical precipitation. The two first steps were dedicated to the crystallization of sodium chloride and potassiummagnesium double salts, respectively. Then, the resulting liquor was desulfated using calcium chloride solution. After that another isothermal evaporation stage was implemented in order to eliminate potassium ions in the form of carnallite, KCl.MgCl2.6H2O. At the end of this step, the recovered solution primarily composed of magnesium and chloride ions was treated by dioxan in order to precipitate magnesium chloride as MgCl2.6H2O.C4H8O2. This compound dried at constant temperature of 100°C gave good quality magnesium chloride hexahydrate. Besides this salt, the various by-products obtained from the different treatment stages are also useful.
Selective recovery of bischofite from sebkha el melah natural brine
Fezei,R.; Hammi,H.; M'nif,A.;
Latin American applied research , 2009,
Abstract: brines are high concentrated aqueous solutions frequently used as raw materials for the recovery of several salts, which are industrially use-ful and necessary in some agricultural applications. this paper deals with a six-stage process for the re covery of magnesium chloride hexahydrate (bischofite) from sebkha el melah natural brine (south of tunisia). it is based on successive evaporation sequences to precipitate firstly sodium chloride and then potassium-magnesium double salts. after that, the mother liquor is cooled to remove magnesium sulphate heptahydrate (epsomite). this step is essential before precipitating the potassiummagnesium double salt kcl.mgcl2.6h2o (carnallite). at the end of this step the recovered solution still contains sulphate ions which may disturb magnesium chloride extraction. in order to overcome this difficulty, a sulphate removal step has been advocated using calcium chloride solution. the treated solution becomes sulphate ion free and thus suitable to be used for bischofite preparation. the investigated procedure makes available the production of a magnesium chloride salt (purity upper than 90%) and various by-products, such as: halite (nacl), gypsum (caso4.2h2o) and epsomite (mgso4.7h2o).
Selective recovery of bischofite from sebkha el melah natural brine
R. Fezei,H. Hammi,A. M'nif
Latin American applied research , 2009,
Abstract: Brines are high concentrated aqueous solutions frequently used as raw materials for the recovery of several salts, which are industrially use-ful and necessary in some agricultural applications. This paper deals with a six-stage process for the re covery of magnesium chloride hexahydrate (bischofite) from Sebkha El Melah natural brine (South of Tunisia). It is based on successive evaporation sequences to precipitate firstly sodium chloride and then potassium-magnesium double salts. After that, the mother liquor is cooled to remove magnesium sulphate heptahydrate (epsomite). This step is essential before precipitating the potassiummagnesium double salt KCl.MgCl2.6H2O (carnallite). At the end of this step the recovered solution still contains sulphate ions which may disturb magnesium chloride extraction. In order to overcome this difficulty, a sulphate removal step has been advocated using calcium chloride solution. The treated solution becomes sulphate ion free and thus suitable to be used for bischofite preparation. The investigated procedure makes available the production of a magnesium chloride salt (purity upper than 90%) and various by-products, such as: halite (NaCl), gypsum (CaSO4.2H2O) and epsomite (MgSO4.7H2O).
Evaluation of Lignin-Calcium Complex as Thermal Stabilizer for Poly Vinyl Chloride  [PDF]
Hussein Ali Shnawa
Materials Sciences and Applications (MSA) , 2011, DOI: 10.4236/msa.2011.26095
Abstract: Chemical modification of lignin was carried out by reacted it with HI acid, then the modified lignin treated with calcium hydroxide to prepare calcium-lignin chelating complex, this derivative was examined as thermal stabilizer for PVC, thermal degradation of PVC neat as blank and containing three weight percents (1, 2, and 4) into polymer was accelerated by heat treatment at 190°C for 2 hr. then PVC films were casting from THF solvent with thickness 0.03 mm. Thermal stabilization activity of this derivative was investigated by using infrared spectroscopy, according to the results obtained calcium-lignin complex have suitable activity to increased PVC stability at low concentration depending on it’s ability to reaction with HCl as well as the chemical structure of lignin that contain phenolic properties.
Potential of Magnesium Chloride for Nutrient Rejection in Forward Osmosis  [PDF]
Yatnanta Padma Devia, Tsuyoshi Imai, Takaya Higuchi, Ariyo Kanno, Koichi Yamamoto, Masahiko Sekine, Tuan Van Le
Journal of Water Resource and Protection (JWARP) , 2015, DOI: 10.4236/jwarp.2015.79060
Abstract: Wastewater may contain high levels of the nutrients: nitrogen and phosphorus. Excessive release of nutrients to the environment can cause severe environmental problem such as eutrophication leading to algal blooms, oxygen deficiency, and fish kills. The forward osmosis (FO) could be a choice of treatment. FO process presents the results of using four kinds of variation in concentration of magnesium chloride (MgCl2) as draw solution and the two kinds of commercial membranes for nutrient rejection in the same cross flow velocity at 0.25 m/s and temperature at 25°C. Nutrients consisting of nitrogen (nitrite, nitrate, and ammonium) and phosphorus (phosphate) in feed solution were successfully rejected with an efficiency of mostly more 95%. The water flux in membrane HTI-NW achieved lower 7.55 - 9.61 L/m2·hr than in membrane HTI-ES that exceeds until 13.58 - 15.10 L/m2·hr. The reverse solute in membrane HTI-NW is seemly constant along all concentration of DS MgCl2 that the chloride diffusion is slightly higher than magnesium. In membrane HTI-ES, the reverse solute of chloride was almost three times than that of magnesium. The concentration of MgCl2 plays a significant role in rejecting nutrients by the Donnan’s potential and the diffusion constant in low and high concentration of DS, respectively.
SEPARATION OF MAGNESIUM CHLORIDE FROM SEA WATER BY PREFERENTIAL SALT SEPARATION (PSS)  [cached]
Khaled Zohdy, Maha Abdel Kareem and Hussein Abdel-Aal*
International Journal of Bioassays , 2013,
Abstract: Magnesium chloride is typically extracted from sea water on an industrial scale by precipitating it as magnesium hydroxide, then converting it to the chloride by adding hydrochloric acid. This process is known as the Dow process which uses the chemical approach in producing magnesium chloride. Kettani and Abdel-Aal [1], proposed a physical separation procedure known as the Preferential Salt Separation (PSS) to obtain magnesium chloride directly from sea water. In principle, the PSS concept is based on the selective separation of salts during the evaporation. In this paper, analysis of the PSS concept is carried out for two proposed distinctive designs: the dynamic (continuous) flow model and the static (batch) flow model. Separation of magnesium chloride is anticipated using solar energy for evaporating sea water. Preliminary experimental results for simulated systems are reported for each case.
A Comparison between Intravenous Magnesium Sulfate and Oral Magnesium Chloride in Mild Preeclampsia  [cached]
A Ghahiri,K Berjis
Journal of Research in Medical Sciences , 2005,
Abstract: Background: Preeclampsia is the second cause of maternal mortality in the United States and accounts for 25% of perinatal mortality. Mild Preeclampsia could be treated without hospitalization, however in some cases, hospitalization seems necessary. Administration of magnesium sulfate (MgSo4) in mild preeclampsia is a matter of controversy. It is obvious that replacing intravenous magnesium sulfate with an oral preparation of magnesium, of course if it gains a sufficiently high serum level, can be easier to use and less expensive. Up to the present time, we have not been able to find any previously done studies using oral magnesium preprations to treat preeclampsia. Thus, we tried to compare serum magnesium level with oral magnesium chloride and intravenous (IV) magnesium sulfate therapy. Methods: This was a comparative experimental study. From January 2002 until April 2003, pregnant patients with mild preeclampsia admitted to Al-Zahra and Beheshti hospitals,Isfahan,Iran, between their 27th and 38th weeks of gestation were divided into 2 groups randomly. There were 33 patients in each group. The first group was treated with IV magnesium sulfate (2 g/h) and the second group received oral magnesium chloride (4 g/2h). Magnesium level was checked in 0, 3, 6, 12 hours. The collected data were analyzed with t-Student test on a computer applying SPSS software. Results: There was no statistical difference between the two groups regarding age, gravidity and gestational age. Magnesium level rose in both groups (P<0.01). Increase of magnesium level in IV magnesium sulfate group was greater than in the other group, and in the magnesium chloride group, therapeutic level could not be achieved. Conclusion: Increase of serum Mg level in IV Mg sulfate group and reaching the therapeutic level was the same as reported before. Increase of Mg level with oral Mg chloride, though measurable, did not reach the therapeutic level. Perhaps with more cases or higher amounts of the drug or other types of Mg preparations we could reach the therapeutic level. Keywords: Preeclampsia, Serum magnesium level, Magnesium chloride, Pregnancy Induced Hypertension (PIH), Oral administration
Intradermal administration of magnesium sulphate and magnesium chloride produces hypesthesia to mechanical but hyperalgesia to heat stimuli in humans
Takahiro Ushida, Osamu Iwatsu, Kazuhiro Shimo, Tomoko Tetsunaga, Masahiko Ikeuchi, Tatsunori Ikemoto, Young-Chang P Arai, Katsutoshi Suetomi, Makoto Nishihara
Journal of Neuroinflammation , 2009, DOI: 10.1186/1742-2094-6-25
Abstract: Magnesium sulphate, magnesium chloride and saline were injected into the skin of the anterior region of forearms in healthy volunteers and injection-induced irritating pain ("irritating pain", for short), tactile sensation, tactile pressure thresholds, pinch-pain changes and intolerable heat pain thresholds of the lesion were monitored.Flare formation was observed immediately after magnesium sulphate or magnesium chloride injection. We found that intradermal injections of magnesium sulphate and magnesium chloride transiently caused irritating pain, hypesthesia to noxious and innocuous mechanical stimulations, whereas secondary hyperalgesia due to mechanical stimuli was not observed. In contrast to mechanical stimuli, intolerable heat pain-evoking temperature was significantly decreased at the injection site. In addition to these results, spontaneous pain was immediately attenuated by local cooling.Membrane-stabilizing effect and peripheral NMDA-blocking effect possibly produced magnesium-induced mechanical hypesthesia, and extracellular cation-induced sensitization of TRPV1 channels was thought to be the primary mechanism of magnesium-induced heat hyperalgesia.Although magnesium ions (Mg2+) are widely distributed throughout the whole organ, the role of Mg2+ in the neural transmission system has not been studied as sufficiently as calcium ions (Ca2+). Much research has mentioned that Mg2+ shows a similar physiological attitude to Ca2+ and it has been reported that both ions have a membrane-stabilizing effect on nerves [1,2]. In addition, Mg2+ is known to act as a competitor to Ca2+, in extracellular matrix [3]. However, the specific role of Mg2+ in neurophysiological transmission, especially concerning peripheral somatosensory systems, has been insufficiently focused on and not understood enough.Among the various studies, the noncompetitive antagonistic action of Mg2+ on N-methyl-D-aspartate (NMDA) receptor, a glutamate receptor, was the focus of various reports [4].
Corrosion Behaviour of AZ and ZA Magnesium Alloys in Alkaline Chloride Media  [PDF]
Mustafa ?. ?teyaka,Edward Ghali,Réal Tremblay
International Journal of Corrosion , 2012, DOI: 10.1155/2012/452631
Abstract: Corrosion behaviour of AZ and ZA magnesium alloys in untreated, aerated, and deaerated chloride media was investigated. The influence of impurity, alloying element, and oxygen on corrosion potential, rate, and pitting was examined in alkaline media saturated with Mg(OH)2 at pH 9 and 25°C. After 8 h immersion, slightly less active corrosion potentials were generally observed in deaerated than oxygen containing solutions. AZ91D and ZA104 alloys recorded much lower corrosion rates in deaerated medium as compared to AZ91E, ZAC 10403 (0.3Ca), and ZACS1040305 (0.3Ca+ 0.5Sr). Generally, ZAC alloy showed the highest corrosion rate, followed by ZACS alloy, and both showed a constant value in the three media with or without oxygen. The effect of oxygen is then dependent on the alloy properties and is not a simple acceleration of the cathodic reaction but could cause also inhibition and/or passivation. Pit depth and distribution were influenced by alloy composition. The pits were found deeper and more localized on AZ and more uniformly dispersed on ZA alloy surfaces. 1. Introduction Magnesium, as a structural material, has numerous advantages with regard to aluminum (lighter by almost 36%) and plastics (almost the same specific density) [1, 2]. Magnesium alloys, in particular those with aluminum (Al) and Zinc (Zn) as alloying elements, are frequently exposed to degradation caused by corrosion. The poor corrosion resistance of many magnesium alloys may be the result of internal galvanic corrosion caused by second phases or impurities. It is well documented that the presence of noble metal impurities (Fe, Ni, and Cu) represents the most detrimental factor influencing the corrosion properties of commercial magnesium alloys [3]. Magnesium suffers pitting when exposed to chloride solutions in nonoxidizing media at open circuit potential. In solutions containing 10 and 1000?ppm of NaCl, the Mg corrosion potential is ?1060 and ?1310?mV versus SHE, respectively [4]. Wilde and Williams [5] measured the corrosion potential changes with time of some corrosion resistant alloys during pitting and found that the corrosion potential decreased in all the alloys when the corrosion potential exceeded the pitting potential. Studies on pitting phenomena on Mg and Mg alloys have compared the pitting behaviour of die-cast alloys and rapidly solidified (thixomolded) Mg alloys [6–9]. For example, the good pitting resistance of die-cast AE alloys was attributed to the presence of Al-rich zones which appeared to act as barrier against pit propagation. Makar and Kruger [10] showed that
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