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Kaolinite is one of the principal rare earth element (REE) ion-adsorption clays that hosts a wide range of elements, including Dy(III) as a representative example. Ammonium sulfate is a typical salt used to leach REEs. Due to the carbon dioxide emissions which occur during ammonia production, it is urgently necessary to develop low environmental pollution leaching agents that can replace (NH4)2SO4. MgSO4 is regarded as the most promising eco-friendly leaching agent. Herein, the first-principles plane-wave pseudopotential method based on the density functional theory (DFT) was used to investigate the stable adsorption structures of Dy(III) and its hydrated ions, MgSO4 leaching agent ions and the corresponding hydrated ions on the surface of kaolinite, which revealed the adsorption mechanism of Dy(III), Mg(II), and SO42− on the silico–oxygen plane and the aluminum–hydroxyl plane of kaolinite. Based on the research results of the steric hindrance effect of Dy(III) on the silico–oxygen plane and the aluminum–hydroxyl plane of kaolinite, the adsorption of Dy(H2O)103+ was more stable on the silico–oxygen plane. It was easier to leach out Dy(III) with MgSO4, while SO42− tended to interact with the rare earth ions in an aqueous solution. The results provide theoretical guidance for efficient rare earth extraction and obtaining novel efficient leaching agents.

Background Magnesium (Mg) is a non-competitive N-methyl d-aspartate receptor antagonist with antinociceptive effects. Multimodal therapy is the optimal strategy for perioperative pain control to minimize the need for opioids. Inflammation caused by tissue trauma or direct nerve injury is responsible for the perioperative pain. The concept of “pre-emptive” analgesia, analgesic strategies administered prior to the stimulus, can modify the peripheral and central nervous system processing of noxious stimuli, thereby reducing central sensitization, hyperalgesia, and allodynia remains controversial. A more encompassing approach to the reduction of postoperative pain is the concept of “preventive” analgesia. The purpose of the study is to detect the proper use of MgSO4 as an analgesic being a non-competitive N-methyl d-aspartate (NMDA). Results There is no statistically significant difference in the haemodynamic parameters, intraoperative (33% vs 20%) and postoperative requirement for analgesics 6.6% vs 10% among groups I and II, respectively. There is no significant difference in the numerical analogue scale, where 16 vs 17 patients with no pain, 12 vs 10 with mild pain, and 2 vs 3 with moderate pain in groups I and II, respectively. Conclusion The use of MgSO4 in a bolus with or without infusion is comparable in the control of intraoperative and postoperative pain.

Background Survival of preterm infants has improved drastically. In addition to significant contribution to neonatal mortality, impact of prematurity among survivors may continue through life impairing long-term physical life through neuro-disability and increased risk of cerebral palsy. Maternal administration of magnesium sulfate prior to impending preterm birth is an effective strategy to reduce neuromorbidity. Aim To investigate the effectiveness of antenatal magnesium sulfate for neuroprotection in preterm infants between 26 and 34 weeks in preventing early neonatal morbidity and mortality. Secondary objective was to assess any adverse events with the use of magnesium sulfate on the mother and neonate. Method This was a prospective observational comparative study for 2 years at our tertiary care hospital of 100 pregnant women who gave preterm births. Fifty infants each were born to mothers who were either not given MgSO4 (Group 1) or given 4gm intravenous loading dose MgSO4 (Group 2), preferably 4 h prior to preterm birth. Results Among all the preterm in our study, 81% delivered between 30 and 34 weeks. There was no significant difference in terms of maternal mortality or serious morbidity including postpartum hemorrhage, caesarian section rates or length of hospital stay among women receiving MgSO4 versus no MgSO4. Mild maternal side effects secondary to magnesium sulfate were experienced in 8% cases. There were no significant differences between both groups for low 5 min APGAR, need for NICU admission, neonatal convulsions, hyperbilirubinemia, necrotizing enterocolitis, periventricular leukomalacia and septicemia. There was a trend toward reduced risk in the magnesium sulfate group for need for mechanical ventilation and ongoing respiratory support, intraventricular hemorrhage, neonatal hypotension, hypothermia, length of NICU stay. IVH was less frequent and less severe in babies exposed to antenatal MgSO4 (8%) as compared to non-MgSO4 group (16%). Neonatal morbidities were more when antenatal MgSO4 was given less than 4 h from delivery. Conclusion MgSO4 is a safe drug to use in antenatal women at risk for impending preterm. Antenatal magnesium sulfate given to women in established preterm labor conferred significant neuroprotective advantage to the neonate. MgSO4 also has protective effect on the need of invasive ventilatory support in preterm infants. Given the breadth of evidence in its favor, it is time for us to start using MgSO4 in clinical practice for neuroprotective intent in all our extreme preterm births.

Ali Reza Sobhani,1 Hossein Farshidi,2 Fariba Azarkish,3 Mahdiya Eslami,2 Ebrahim Eftekhar,4 Mansoor Keshavarz,5 Nepton Soltani6 1Clinical Pathology Department, Faculty of Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran; 2Cardiovascular Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran; 3Molecular Medicine Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas, Iran; 4Endocrinology and Metabolism Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran; 5Physiology Department, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran; 6Physiology Department, School of Medicine, Isfahan University of Medical Sciences, Isfahan, IranCorrespondence: Nepton SoltaniPhysiology Department, School of Medicine, Isfahan University of Medical Sciences, Isfahan, IranTel +98 9133251067Fax +98 36688597Email neptun.soltani@med.mui.ac.irPurpose: Given the beneficial effect of MgSO4 on the cardiovascular system, this study was designed to investigate the effect of MgSO4 administration on suppressing some atherosclerotic risk factors in moderate coronary artery disease patients with one or two atherosclerotic vessels.Patients and Methods: In a randomized double-blind placebo-controlled clinical trial study, 64 patients with moderate coronary artery disease (55– 69% stenosis) were selected according to angiography findings. Patients were divided into four groups including patients with one or two atherosclerotic vessels treated with MgSO4 (Mg-treated-VR1, Mg-treated-VR2, respectively), placebo treated patients with one or two atherosclerotic vessels (Control-VR1, Control-VR2, respectively). The patients received either placebo or MgSO4 supplement capsule containing 300 mg MgSO4 for six months on a daily basis. ESR, Ca/Mg ratio, urine Mg level, serum Mg, fibrinogen, homocysteine, uric acid, Na, K, Ca, CRP, T3, T4, TSH, BUN, and Cr concentrations were measured at baseline and every three months.Results: Serum T3, Ca, K, homocysteine, CRP, and Mg concentrations were significantly improved in Mg-treated groups compared to placebo groups.Conclusion: The results of this study showed that despite the slight change in serum magnesium level, oral administration of MgSO4for six months could slightly reduce the serum levels of some inflammatory and vascular factors in moderate coronary artery disease patients.Keywords: atherosclerosis, MgSO4, fibrinogen, CRP, homocysteine, thyroid hormones

Magnesium sulfate (MgSO4) solution has been chosen as alternative contrast medium in computed tomography scanning (CT-scan). The solution of MgSO4 was a good electrochemical property especially in the blood medium. It was found that MgSO4 in blood medium served as an antioxidant reagent because cyclic voltammogram had only one reduction current peak at 0.9 V, while iodine compounds were used as a common contrast medium in CT-scan; they had two oxidation current peaks in the blood medium at 0.73 V and 0.23 V. In addition, the iodine compounds caused many problems when used as a contrast medium, but they were the only contrast media used for this pur-pose. It was found that using MgSO4 solution as an alternative contrast medium in rabbits enhanced CT-scan in the resolution and increasing Hounsfield unit (HF) values of kidney and heart organ, as compared with that using iodine compound at the same dose.

Ali Reza Sobhani,1 Hossein Farshidi,2 Fariba Azarkish,3 Mahdiya Eslami,2 Ebrahim Eftekhar,4 Mansoor Keshavarz,5 Nepton Soltani6 1Clinical Pathology Department, Faculty of Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran; 2Cardiovascular Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran; 3Molecular Medicine Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas, Iran; 4Endocrinology and Metabolism Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran; 5Physiology Department, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran; 6Physiology Department, School of Medicine, Isfahan University of Medical Sciences, Isfahan, IranCorrespondence: Nepton SoltaniPhysiology Department, School of Medicine, Isfahan University of Medical Sciences, Isfahan, IranTel +98 9133251067Fax +98 36688597Email neptun.soltani@med.mui.ac.irPurpose: Given the beneficial effect of MgSO4 on the cardiovascular system, this study was designed to investigate the effect of MgSO4 administration on suppressing some atherosclerotic risk factors in moderate coronary artery disease patients with one or two atherosclerotic vessels.Patients and Methods: In a randomized double-blind placebo-controlled clinical trial study, 64 patients with moderate coronary artery disease (55– 69% stenosis) were selected according to angiography findings. Patients were divided into four groups including patients with one or two atherosclerotic vessels treated with MgSO4 (Mg-treated-VR1, Mg-treated-VR2, respectively), placebo treated patients with one or two atherosclerotic vessels (Control-VR1, Control-VR2, respectively). The patients received either placebo or MgSO4 supplement capsule containing 300 mg MgSO4 for six months on a daily basis. ESR, Ca/Mg ratio, urine Mg level, serum Mg, fibrinogen, homocysteine, uric acid, Na, K, Ca, CRP, T3, T4, TSH, BUN, and Cr concentrations were measured at baseline and every three months.Results: Serum T3, Ca, K, homocysteine, CRP, and Mg concentrations were significantly improved in Mg-treated groups compared to placebo groups.Conclusion: The results of this study showed that despite the slight change in serum magnesium level, oral administration of MgSO4for six months could slightly reduce the serum levels of some inflammatory and vascular factors in moderate coronary artery disease patients.Keywords: atherosclerosis, MgSO4, fibrinogen, CRP, homocysteine, thyroid hormones

This protocol involves the NH4Cl catalyzed Pictet−Spengler reactions of tryptamine and arylaldehydes in anhydrous MeOH solvent to gives corresponding tetrahydro-β-carbolines (THβC) with 90% yield. This methodology offers mild, efficient and green reagent towards the synthesis THβC with tolerance of wide functional group. This is the first report of Pictet–Spengler reaction using mild NH4Cl in MeOH solvent.

Eclampsia is a common complication of preeclampsia patients and can be life-threatening for both the mother and the fetus. Hence, timely intervention and appropriate management of this detrimental condition are extremely crucial. Eclampsia is described as the occurrence of generalized convulsions in patients with preeclampsia. Magnesium sulfate (MgSO4) is the drug of choice for treating and preventing eclampsia. This review aims to study and analyze the available literature on the pathogenesis of eclampsia, the pharmacology of MgSO4, and its effectiveness in the management of eclampsia. Other proposed treatments and their comparative study with MgSO4 are also discussed. Additionally, we examine the data regarding the impact of eclampsia, its public health burden, and the cost-effectiveness of MgSO4. One of the major drawbacks associated with the use of MgSO4 in low-income countries has been the cost of treatment and the lack of resources. We have analyzed the trials that have proposed alternate treatment regimens which could shape new guidelines to resolve these issues. For this review, we extensively studied abstract and full-text articles from multiple databases. This article discusses the pathophysiology of eclampsia, the pharmacology of MgSO4, the issues surrounding eclampsia management, and how MgSO4 benefits these patients.

During the leaching process of ionic rare earth ore (ICREO), ion-exchangeable phase calcium (IEP-Ca) and ion-exchangeable phase aluminum (IEP-Al) are leached along with rare earth, which causes many problems in the enrichment process, such as increasing the precipitant agent consumption and rare earth loss, etc. The agitation leaching kinetics and the column leaching mass transfer process of IEP-Ca and IEP-Al were studied to understand the leaching behavior of impurity in ICREO, which provides guides for the adjustment of the leaching process and to limit the co-leaching of impurities. IEP-Ca and IEP-Al were leached by ion exchange, with the leaching agent cations and the leaching kinetics described by an internal diffusion-controlled shrinking core model with an apparent activation energy of 8.97 kJ/mol and 10.48 kJ/mol, respectively. In addition, a significant reduction in the leaching efficiency of aluminum was caused by the hydrolysis reaction reinforced by the increase in MgSO4 concentration and temperature. The leaching kinetic data of IEP-Ca and IEP-Al was verified by the column leaching mass transfer process. There was a synchronous increase in the peak concentration of the outflow curve and leaching efficiency of calcium with the concentration of MgSO4 since IEP-Ca was easily leached. Therefore, as the leaching efficiency of calcium was already very high in the 0.20 mol/L MgSO4 leaching process, the leaching rate of calcium was limited by the leaching temperature and injection rate of MgSO4. For aluminum, the hydrolysis of Al3+ was promoted by increasing the MgSO4 concentration and the leaching temperature, thereby effectively reducing the content of aluminum in the leachate.

Objective The use of antenatal magnesium sulfate (MgSO4) has been associated with neuroprotective effects. One of its' proposed mechanisms of action includes antagonism of calcium channels. Calcium influx is important for closure of ductus arteriosus. We hypothesized that antenatal MgSO4 exposure may be associated with an increased risk of hemodynamically significant patent ductus arteriosus (HsPDA) in premature infants (PI). Study Design A prospective cohort study conducted in two parts. PI (< 32 weeks and 1.5 mm and BNP levels > 40 pg/mL or NTproBNP > 10,200 pg/mL. Infants were divided into two groups based on antenatal MgSO4 exposure. Data were analyzed using SPSS 23. Difference in baseline characteristics and antenatal steroid use in the two groups was analyzed. A matched group analysis was performed to adjust for the difference in the numbers between the two groups. A p-value Results There was no significant difference seen in baseline characteristics or use of antenatal steroids in exposed versus unexposed (n = 95 vs. n = 10). There was a significant negative correlation between antenatal MgSO4 exposure and HsPDA in PI (p ≤ 0.05). However, this association was not significant after matched group analysis. Conclusion Antenatal MgSO4 exposure is not associated with an increased risk of HsPDA. It may be associated with a decreased likelihood of HsPDA.

Nyeri pascabedah masih menjadi masalah dan perhatian di dunia. Pemberian analgetik preventif merupakan salah satu cara untuk mengurangi nyeri pascabedah. Beberapa obat digunakan sebagai terapi analgetik preventif antara lain opioid dan NSAID, namun obat ini mempunyai banyak efek samping. MgSO4 dapat digunakan sebagai analgetik preventif karena bersifat antagonis reseptor NMDA nonkompetitif. Tindakan operasi yang memiliki skor nyeri yang tinggi salah satunya adalah simple mastectomy dengan skor nyeri 4 sampai 8. Penelitian ini bertujuan mengetahui pengaruh MgSO4 i.v. dengan dosis bolus 50 mg/kgBB 20 menit prainduksi terhadap kebutuhan analgetik pasca-simple mastectomy. Penelitian ini merupakan penelitian analitik komparatif dengan data tidak berpasangan secara prospektif dengan uji klinis acak terkontrol buta ganda (RCT double blind) yang dilakukan terhadap 26 subjek penelitian yang menjalani simple mastectomy di RSUP Dr. Hasan Sadikin Bandung pada bulan Agustus sampai Desember 2018. Analisis statistik pada data numerik diuji dengan uji t berpasangan, sedangkan data kategorik diuji dengan uji chi-Square. Subjek dibagi menjadi kelompok M (MgSO4 20% 50 mg/kgBB) dan kelompok C (NaCl 0,9%). Hasil penelitian ini didapatkan kebutuhan opioid pascabedah pada kelompok yang diberikan MgSO4 lebih rendah dibanding dengan kelompok yang mendapatkan NaCl dengan perbedaan bermakna (p

Preeclampsia is a dangerous complication for pregnant women and their fetuses, this can cause damage to body organs namely heart failure, kidney failure, liver dysfunction, blood clotting disorders, death for the mother and fetus, if not immediately addressed well and correctly. Management of severe preeclampsia by administering MgSO4 intravenously to mothers as prevention of seizures, one of the nursing actions to overcome preeclampsia patients is the provision of relaxation techniques Slow stroke back massage. The objective of this research to determine the effectiveness of MgSO4 Therapy and Slow Stroke Back Massage on Blood Pressure Response In Severe Preeclampsia Pregnant Women at Roemani Hospital Muhammadiyah Semarang. This research uses the quasi-experimental design with the pre and post test perspective. This research measured 32 the pregnant women with severe preeclampsia at Roemani Muhammadiyah Hospital Semarang from purposive sampling technique. The result of this research was shown the effect of blood pressure reduction in all preeclampsia pregnant women given MgSO4 therapy and slow stroke back massage. There is a significant influence on the provision of MgSO4 therapy and slow stroke back massage on the blood pressure response of severe preeclampsia pregnant women.

MgSO 4 is used as a tocolytic agent. It is considered to be a calcium channel antagonist, but a different mechanism of its action might be involved. The aim of this study was to examine the contribution of calcium concentrations and potassium channels in the mechanism of MgSO 4 -mediated uterine relaxation. Isolated uteri from female Wister rats were treated with increasing MgSO 4 concentrations (0.1-30 mM). MgSO 4 induced dose-dependent inhibition of spontaneous activity. Addition of Ca 2+ (6 mM and 12 mM) stimulated uterine contractile activity and attenuated the inhibitory activity of MgSO 4 . In order to analyze the role of different subtypes of potassium channels, Ca 2+ -stimulated uteri were pretreated with glibenclamide (Glib), a selective ATP-sensitive potassium channel inhibitor (K ATP ), tetraethylammonium (TEA), a non-specific inhibitor of large conductance calcium-activated potassium channels (BK Ca ), and 4-aminopyridine (4-AP), a voltage-sensitive potassium channel inhibitor (Kv), at concentrations that had no effect per se . Pretreatment with 4-AP had no effect on MgSO 4 -mediated relaxation of Ca 2+ -stimulated uteri. The relaxing effect of MgSO 4 was potentiated by pretreatment with glibenclamide. Pretreatment with TEA attenuated the MgSO 4 -mediated decrease in frequency. Our results suggest that MgSO 4 acts as a general calcium antagonist that influences Ca 2+ -mediated potassium channels. Furthermore, it seems that MgSO 4 uterine relaxation activity is partially mediated by selective ATP-sensitive potassium channels, suggesting an ATP-dependent role. https://doi.org/10.2298/ABS180615031S Received: June 15, 2018; Revised: July 6, 2018; Accepted: July 6, 2018; Published online: July 16, 2018 How to cite this article: Sokolovic D, Drakul D, Orescanin-Dusic Z, Tatalovic N, Pecelj M, Milovanovic S, Blagojevic D. The role of potassium channels and calcium in the relaxation mechanism of magnesium sulfate on the isolated rat uterus. Arch Biol Sci. 2019;71(1):5-11.

Anhydrous sulfate minerals are abundant in the active fumaroles with highly oxidizing conditions on the scoria cones of the Tolbachik volcano. The mineral itelmenite, ideally Na2CuMg2(SO4)4, containing isomorphous admixture of Zn, was described in 2018, whereas glikinite, ideally Zn3O(SO4)2, was described in 2020. Synthetic analogs of both minerals were obtained during studies of phase formation in the Na2SO4–CuSO4–MgSO4–(ZnSO4) systems which lead to essentially different results. Solid-state syntheses resulted in formation of several compounds previously known as minerals only. Both Zn- and Mg-containing analogs of itelmenite were prepared and exhibit slight deviations from the ideal Na2CuM2(SO4)4 stoichiometry. The Mg compound could be prepared single-phase which allowed the study of its thermal expansion and IR spectroscopy. Na2CuMg2(SO4)4 and Na2CuZn2(SO4)4 were evaluated for Na+-ion diffusion. For the Zn compound, several by-products were observed which are synthetic analogs of puninite Na2Cu3O(SO4)2, as well as hermannjahnite CuZn(SO4)2 and glikinite-type (Zn,Cu)3O(SO4)2. All of them were prepared via solid-state reactions in open systems. The Na2CuMg2(SO4)4, Na2CuZn2(SO4)4 and (Zn,Cu)3O(SO4)2 were structurally characterized by the single-crystal XRD. In the Zn-bearing system, the admixture of Cu2+ likely controls the formation of itelmenite-type and glikinite-type phases. The results of the experiments allowed to deduce possible scenarios of the formation processes of itelmenite and some other endemic fumarolic minerals. Our study shows that outstanding mineralogical diversity observed in the fumaroles of the Tolbachik scoria cones is not only due to the formation from the gas enriched by transition metals and involves also intensive exchange with the host basaltic scoria. Similar processes seem also to be responsible for the recrystallization of many other mineral species observed in high-temperature fumaroles resulted from the recent eruptions.

Background Pharmacy workers in Bangladesh play an important role in managing pregnancy complications by dispensing, counselling and selling drugs to pregnant women and their families. This study examined pharmacy workers’ drug knowledge and practice for pre-eclampsia and eclampsia (PE/E) management, including antihypertensives and anticonvulsants, and determine factors associated with their knowledge. Methods A cross-sectional survey with 382 pharmacy workers in public facilities (government) and private pharmacies and drug stores assessed their knowledge of antihypertensive and anticonvulsant drugs. ‘Pharmacy workers’ include personnel who work at pharmacies, pharmacists, family welfare visitors (FWVs), sub-assistant community medical officers (SACMOs), drug storekeepers. Exploratory and multivariate logistic models were used to describe association between knowledge of medicines used in pregnancy and demographic characteristics of pharmacy workers. Results Overall, 53% pharmacy workers interviewed were drug store owners in private pharmacies while 27% FWVs/SACMOs, who are government service providers also work as drug prescribers and/or dispensers in public facility pharmacies. Majority of pharmacy workers had poor knowledge compared to correct knowledge on both antihypertensive (77.8% vs 22.3%; p 4) (82.2% vs 17.8%; p P Conclusions Pharmacy workers’ knowledge and understanding of antihypertensive and anticonvulsant drugs, particularly for prevention and management of PE/E is limited in Bangladesh. Most pharmacies surveyed are private and staffed with unskilled workers with no formal training on drugs. Expansion of maternal and newborn health programs should consider providing additional skills training to pharmacy workers, as well as regulating these medicines at informal pharmacies to mitigate any harmful practices or adverse outcomes of unauthorized and incorrectly prescribed and used drugs. It is important that correct messaging and medicines are available as drug stores are often the first point of contact for most of the women and their families.

Bi(NO3)3·5H2O/MgSO4 was developed as an efficient and green reagent for the nitration of aromatic compounds under mechanochemistry (or ball milling) condition. While aromatics with weak activating groups such as phenyl could be nitrated by this reagent with 100% conversion, aromatics with weak deactivating groups such as chloro- or bromo- could also be nitrated but with moderate conversion and regioselectivity with big para/ortho ratios. The in situ generated N2O4 or NO2 due to the decomposition of Bi(NO3)3·5H2O promoted by MgSO4 should be responsible for this mechanochemical nitration.

The accumulation of salts in building stones can lead to weathering features such as scaling, sanding or even slab detachment. To detect salts in walls at the early stages and to predict their evolution, the non-destructive technique (NDT) Infrared Thermography (IRT) was tested in a stimulated way. The main objective was to trial this technique in order to obtain more information such as the type of salt, its precise location and its concentration in building stones. Three building materials were studied, including two natural limestones and a reconstituted stone. Samples were submitted to immersion/drying tests in water and in salt solutions of Na2SO4, NaCl and MgSO4 at 7%, 14% and 26% in weight during 20 cycles of 24 h. The weight of the samples and the surface colour were recorded after each cycle. After 1, 5, 10 and 15 cycles, 3 samples were taken out for active IRT measurements. The results showed that when the porosity and the capillarity are low, the intake of salts into the porous network is low and the thermal response of the stone to heating (ΔTmax) corresponds to the salt thermal signature and has no relation with concentration. On the other hand, when the initial porosity is high, salts crystallize inside the porous network and porosity decreases. Hence, the thermal response of the porous stone is related to salt concentration and the ΔTmax increases until the stone starts to disaggregate. Active IRT is a promising NDT adapted to identify and quantify salts within building stones during the first states of accumulation.

L -carnitine plays physiologically important roles specifically to decrease triglycerides, very low density lipoprotein (VLDL) and cholesterol. Considering these facts, it is believed to be helpful in the reduction of cardiovascular diseases and diabetes. Physicochemical properties of L -carnitine in aqueous or mixed aqueous solutions are scarcely available in literature. Such properties will be useful in understanding the interactions of L -carnitine with other cellular components like trimethylamine-N-oxide (TMAO), dextrose ( D -glucose) and NaCl. The values of densities (ρ) and speeds of sound (u) of L -carnitine were measured over the molality range of m = 0.05 mol·kg−1 to m = 0.3 mol·kg−1 at temperature T = 293.15 K to T = 313.15 K in water and in aqueous solutions of TMAO, dextrose, and NaCl. Using these data, values of apparent molar volume (V2,m,φ) and apparent molar adiabatic compressibility (Ks,2,m,φ) have been determined. The results obtained from these measurements have been used to derive the standard partial molar volume ( V 2 , m o ), standard partial molar adiabatic compressibility ( K s , 2 , m o ), standard partial molar volume of transfer ( Δ tr V 2 , m o ) and standard partial molar isentropic compressibilities of transfer ( Δ tr K S , 2 , m o ) from water to aqueous solutions of TMAO, dextrose, and NaCl. Through Isothermal Titration Calorimetry (ITC), the enthalpies of dilution ( Δ dil H m ) of L -carnitine in water (over a temperature range of T = 293.15 K to T = 313.15 K) and in aqueous solutions of TMAO, dextrose, and NaCl have been determined. The values of standard molar enthalpy of dilution ( Δ dil H m o ) and their transfer values ( Δ tr Δ dil H m o ) have been derived from these measurements. The results have been discussed in terms of possible intermolecular interactions. The data suggest that there is overall balancing of hydrophobic and hydrophilic interactions in system containing L -carnitine and TMAO in aqueous solution, but hydrophobic effect dominates when the co-solute is NaCl or dextrose.

Background Magnesium (Mg) deficiency contributes to the pathophysiology of numerous diseases. The therapeutic use of Mg has steadily increased over time. The increased in-hospital use of intravenous (IV) magnesium sulfate (MgSO4) warrants more extensive investigation regarding the safety of the therapy. The aim of this study was to determine the safety of IV MgSO4 infusion on cardiovascular, liver, kidney, and metabolic markers in adults. Methods Twelve volunteers were randomized to one of two cross-over conditions: (a) IV infusion of MgSO4 in 5% dextrose followed by IV infusion of 5% dextrose 1 week later or (b) IV infusion of 5% dextrose followed by IV infusion of MgSO4 in 5% dextrose 1 week later. An electrocardiogram was recorded continuously during the infusions. Blood was drawn pre- and post-infusion for blood count (high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides). Results: Serum Mg increased from pre- to post-infusion in the MgSO4 + 5% dextrose group (p < 0.0001). The QRS interval length increased from pre- to post-infusion in the MgSO4 + 5% dextrose group (p < 0.04). Additionally, serum glucose concentration increased in the MgSO4 + 5% dextrose group (p = 0.04). These significant findings were modeled with gender and age as covariates. No other significant differences were found. Conclusions The administration of IV infusion of MgSO4 (4 g/100 mL) in 5% dextrose over a 4-hour treatment period poses no significant deleterious effects on cardiovascular, liver, kidney, or metabolic function. Relevance for patients IV infusion of MgSO4 may be used for certain treatment indications without significant concern for systemic or organ toxicity.

Ebru Celik Kavak,1 Funda Gulcu Bulmus,2 Ozgur Bulmus,3 Salih Burcin Kavak,1 Nevin Kocaman4 1Department of Obstetrics and Gynecology, 2Vocational School of Health Services, 3Department of Physiology, 4Department of Histology and Embryology, School of Medicine, Firat University, Elazig, Turkey Aim: The aim of the present study was to assess the protective effects of magnesium sulfate (MgSO4) on ischemia/reperfusion (I/R) induced ovarian damage in a rat ovarian torsion model.Methods: Forty-two female Sprague Dawley rats were included in the study. They were divided into six groups as Group 1, sham; Group 2, bilateral ovarian torsion; Group 3, bilateral ovarian torsion–detorsion; Group 4, MgSO4–sham; Group 5, MgSO4–bilateral ovarian torsion; Group 6, bilateral ovarian torsion–MgSO4–detorsion. Both torsion and detorsion periods lasted 3 hours. In Groups 4, 5 and 6, MgSO4 (600 mg/kg) was administered by intraperitoneal route 30 minutes before sham operation, torsion and detorsion, respectively. At the end of the study period, both ovaries were removed. One of the ovaries was used for histopathological analyses and the other for biochemical analyses.Results: In the torsion–detorsion group, all the histopathological scores were higher compared to the sham and torsion only group (p

In 2013, the U.S. Food and Drug Administration issued a safety warning that cautioned against using magnesium sulfate (MgSO4) injections for more than 5 to 7 days to stop preterm delivery due to the bone problems subsequently observed in infants. However, the warning was mainly based on case reports, and further investigation is necessary to determine whether prolonged MgSO4 use increased infant fractures. To evaluate whether prolonged MgSO4 use for tocolysis increased the risk of subsequent fractures among infants. A retrospective population-based cohort study was conducted with a new-user study design using the National Health Insurance Database in Taiwan. We included pregnant women aged between 12 and 55 years old who delivered a live-born singleton. The enrollment period was from January 1, 2012 to December 31, 2014. The exposure group was defined as pregnant women who received MgSO4 injection for >5 days during pregnancy, while those not receiving any tocolytics were the reference group. The outcome was any bone fracture among the infants during the 2-year follow-up period. Propensity score matching and Cox proportional hazards regression models were used to estimate the hazard of fractures. We further studied the effect of MgSO4 treatment with varied dosages and durations of treatment in the sensitivity analyses. Among the 4092 pregnant women in the database, 693 (16.9%) of them were included in the exposure group. The hazard ratio of infant fractures among prolonged MgSO4 users was not significantly different from that of tocolytic nonusers in adjusted models (adjusted hazard ratio (aHR) = 1.48; 95% confidence interval (CI) = 0.59–3.71). A similar lack of significance was found in the sensitivity analyses (aHR = 1.45; 95% CI = 0.40–5.28 for larger treatment dosage; aHR = 2.52; 95% CI = 0.49–12.98 for longer treatment duration). Prolonged MgSO4 tocolysis use did not increase the risk of infant fractures. Our findings reconfirmed the safety of MgSO4 as a tocolytic treatment.

Introduction: Zataria multiflora Boiss. is an indigenous herbal plant found in many parts of Iran. This herb is traditionally used as a remedy for treating gastrointestinal disorders including diarrhea. Despite the existence of few pharmacological evidences which support the antispasmodic action of Z. multiflora in vitro, there is no scientific report about therapeutic efficacy of Z. multiflora in animal models. The objective of this research was to investigate the antispasmodic activity of hydroalcoholic and hexane extracts of Z. multiflora on intestinal peristaltic movement as well as assessment of its antidiarrheal action in mice. Methods: Dried leafy branches of Z. multiflora were coarsely powdered and subjected to extraction by ethanol or hexane in a percolator apparatus. Antispasmodic activity of Z. multiflora in vivo was assessed by investigating effect of the extracts on intestinal charcoal meal transit. The antidiarrheal activity of Z. multiflora extracts was evaluated by castor oil and magnesium sulfate‑induced diarrhea. The inhibitory effects of the extracts were compared with the standard drug loperamide. Results: The antispasmodic activity of Z. multiflora (20 & 40 mg/kg) hydroalcoholic and hexane extracts was confirmed by a reduction in the distance traveled by charcoal meal alongside the small intestine. Z. multiflora extracts (20 & 40 mg/kg) also significantly attenuated the castor oil and magnesium sulfate‑induced diarrhea. Loperamide was more efficacious in reducing number of total stools in both models of diarrhea. Conclusion: The obtained results have established a pharmacological evidence for the folkloric use of the Z. multiflora as an antidiarrhoeal and spasmodic agent.

BACKGROUND: In neonates, birth asphyxia is a serious condition. It results in high risk of morbidity and mortality. It is also associated with permanent neuro developmental deficits among survivors. OBJECTIVES: The main objective of the study is comparing the efficacy of intravenous magnesium sulphate (MgSO4) with placebo in neonates with severe birth asphyxia in terms of neurological outcome. METHOD: A total of 66 subjects were recruited in Pediatrics Medicine Unit-II, DHQ Hospital, Faisalabad from April 2011 to December 2011. Neonates divided into two groups A & B (33 patients in each group) with history of birth asphyxia. Neonates of group-A were given MgSO4 through I.V route(3 doses 250 mg/kg/dose, 24 hours interval) and group B received normal saline(3 doses 1 ml/kg/dose 24 hours interval). During stay in NICU all Neonates were regularly neurologically assessed. RESULTS: Mean age (hour) was observed 2.82±1.35 and 3.24±1.60 in both A and B groups respectively. Total of 18(54.5%) subjects in group A and 19(57.6%) subjects in group B had 37-38 weeks while, 15(45.5%) and 14(42.4%) subjects had 39-40 weeks of gestational age respectively. At discharge time, neurological findings (neonatal reflexes) were improved in 25(75.8%) subjects in A group and 15(45.4%)subjects in B group. Statistically significant P value was found to be 0.002 for oral feed (sucking). Normal CT brain was seen in 28(84.9%) subjects in group A and 17(51.5%) subjects in group B. CONCLUSION: Neurological outcome at discharge were improved with the treatment of postnatal I/V magnesium sulfate in neonates with severe birth Asphyxia when given early after birth having severe perinatal asphyxia.

Introduction: The aim of this systematic review is to investigate the effects of perioperative intravenous administration of MgSO4 on postoperative pain, analgesic consumption and adverse effects in patients undergoing orthopedic surgery. Methods: Two investigators independently searched for articles on randomized controlled trials (RCTs) from 1998 to 2016 in Pubmed, Web of science and Google scholar. We evaluated clinical outcomes, comparing postoperative pain scores, cumulative analgesic consumption, time to first analgesia, and adverse effects between orthopedic surgery patients with and without the administration of MgSO4. Results: After screening 2350 articles, 11 RCTs (with a total sample size of 535 subjects) were included in this systematic review. Perioperative intravenous administered MgSO4 could reduce postoperative pain intensity compared with control in 6 trials (55%), but without significant difference in 5 trials (45%). With MgSO4 treatments, postoperative analgesic consumption was significantly reduced in 8 trials (73%), and without significant difference in 2 trials (18%). Two trials evaluated the time to first request of analgesic after surgery and showed prolong of 2.3 hours and 93 minutes respectively. MgSO4 group had less postoperative nausea (relative risk [RR] = 0.32, 95% confidence interval [CI] = 0.12–0.82, number needed to harm [NNH] = 8.8), vomiting (RR = 0.38, 95% CI = 0.15–0.92, NNH = 9.7), and shivering (RR = 0.31, 95% CI = 0.11–0.88, NNH = 5.2). Conclusion: Perioperative intravenous administration of MgSO4 in orthopedic surgery could reduce postoperative analgesic consumption and adverse effects such as vomiting, nausea, and shivering. These trials do not provide convincing evidence of beneficial effects on postoperative pain intensity and the time to first analgesic request. More trials should be conducted for the roles of MgSO4 in pain management for orthopedic surgery. However, intravenous MgSO4 administration should be considered as a strategy to relieve postoperative pain in orthopedic surgery patients.

Shivering, as a result of impaired thermoregulatory, is frequent during surgery under spinal anesthesia. The purpose of this study was to compare the anti-shivering effect between intravenous MgSO4 and pethidine during transurethral resection of the prostate under spinal anesthesia.This study was a randomized double-blind controlled trial in 42 patients with American Society of Anesthesiologist (ASA) physical status II or III, aged 60−70 years who underwent transurethral resection of the prostate at the central operating theater of Dr. Hasan Sadikin General Hospital Bandung within March–September 2014. The patients were divided into MgSO4 group and pethidine group. Characteristics of data, the incidence of shivering, body core temperature, vital signs monitoring, and adverse events were recorded. Antishivering effect of MgSO4 was better compared to pethidine, with the incidence of shivering in operating theatre was 4/21 vs 9/21. However, in the recovery room, the incidence of shivering was the same for both groups (1/21). It is concluded that the administration of intravenous MgSO4 before spinal anesthesia clinically reduces the incidence of shivering during surgery and has a better anti-shivering effect compared to intravenous pethidine.

Background Magnesium sulfate (Mg SO 4 ) has been used as a common therapy for preeclampsia and eclampsia for many years. Mg SO 4 decreases peripheral vascular resistance so as to reduce maternal blood pressure. Whether placental blood vessels react to Mg SO 4 in the same patterns as that in maternal vessels is largely unknown. Methods and Results This study compared placental vessels ( PV ) versus nonplacental vessels (non‐ PV ) in human and animal models. Mg SO 4 ‐caused vascular dilation was significantly weaker in PV than that in non‐ PV . Prostaglandin I 2 synthetase affected Mg SO 4 ‐mediated vasodilatation in PV , not in umbilical vessels, while cyclooxygenase did not influence Mg SO 4 ‐induced relaxation in both PV and non‐ PV . Mg 2+ ‐caused vasodilatation was mainly through calcium channels. In PV , calcium channel activities were significantly weaker in PV than that in non‐ PV . Relative mRNA expression of CACNA 1D , CACNB 2 , and CACNB 3 was significantly higher in PV than those in umbilical vessels, despite the fact that the expression of CACNA 1F was less in PV . The contractile phenotype of smooth muscle cell marker ( CALD 1) was less and the synthetic phenotype ( MYH 10) was more in PV than that in UV . Conclusions These results demonstrated that PV were characterized by much weaker responses to Mg SO 4 compared with nonplacental vessels. The difference was related to weaker calcium channel activity and minor contractile phenotype smooth muscle cells in PV , providing important information for further understanding treatments with Mg SO 4 in preeclampsia.

Objective: To compare the effectiveness of Morphine alone and Morphine with MgSo4 in pain management after CABG surgery. Methods: This randomized control trial was conducted in the department of anesthesia and critical care Choudhary Pervaiz Ellahi Institute of Cardiology, Multan from November 2016 to June 2017. All collected data was entered and analyzed by using computer software SPSS version 23.1. Quantitative data like age, VAS score was analyzed and presented as mean and standard deviation. Similarly qualitative data like gender and ASA status was calculated and presented as frequency and percentages. Independent sample T-test was applied for significance of VAS score. P value ≤0.05 was considered as significant. Results: A total number of 150 patients of both genders were included in this study. The main outcome variables of our study were VAS score. It was observed that, in group (M), the mean VAS score after 4, 12 and 24 hours of operation was 5.24±1.61, 5.8±2.27 and 5.44±2.27 respectively. And in group (MM), the mean VAS score after 4, 12 and 24 hours of operation was 4.36±2.58, 3.48±2.10 and 4.12±1.05 respectively. It was noted that both groups had statically significant difference of VAS score, as group (M) had higher VAS score than group (MM). Conclusion: Morphine with Mgso4 has better efficacy as compared to morphine alone when used as analgesic agent after CABG surgery.

In this paper presents the effects of the combined action of two aggressive environments. Then determine the effect of the content of sulphate ions or chloride on the growth of microorganisms and the possible impact of chemical-biological corrosion properties of moisture, mechanical structure of the ceramic materials. To assess changes in the samples as a result of corrosion-induced chemical and fungi, the following parameters were selected: a chemical analysis, the goal was to determine the content of sulphate ions or chloride; pH; colony-forming units; mass moisture and absorbability of water, and research on the microstructure under the scanning electron microscope. The results allowed to formulate a number of statements: ceramic materials are resistant to mould; original ceramic salt contamination of chloride ions or sulphate did not stop the operation of the biological environment; by the co-operation of both aggressive environments, material properties change.

Background Since acute respiratory failure (ARF) is a life-threatening complication, particularly in the gestational period, differential diagnosis and rapid treatment are required. Among the various causes of sudden onset of ARF, thyroid storm is a rare cause in a parturient complicated with well-controlled hyperthyroidism. In this case report, we describe a parturient with hyperthyroidism in whom a thyroid storm manifesting congestive heart failure and pulmonary edema developed just before an emergency ceasarean section, even though hyperthyroidism was well-controlled with antithyroid drugs. Case presentation A 36-year-old pregnant woman was diagnosed as having clinical chorioamnionitis, and an emergency cesarean section was performed at 25 weeks of pregnancy. She had a complication of hyperthyroidism accompanied by mild mitral regurgitation, and she had been treated with methimazole. She was treated with ritodrine and MgSO4 for the threat of premature delivery. At the preoperative consultation, her percutaneous oxygen saturation (SpO2) was 98% on room air. When she was admitted to the operating room, her heart rate and blood pressure were 130 beats/min and 196/78 mmHg, respectively. SpO2 was 88% on room air without any symptoms; however, just after starting oxygen administration via a facemask, she complained of severe respiratory distress and became agitated. Partial pressure of arterial oxygen was 108 mmHg with an inspiratory oxygen fraction of 1.0. Chest radiography revealed pulmonary congestion, and transesophageal echocardiography revealed normal right ventricular function without an embolus and severe mitral regurgitation with preserved left ventricular function. Contrast-enhanced computed tomography after the operation revealed no pulmonary embolus but revealed a pulmonary effusion, and free triiodothyronine level was increased at the onset of dyspnea. Therefore, we diagnosed the causes of sudden onset of dyspnea as pulmonary edema and congestive heart failure induced by a thyroid storm. Conclusion Sudden onset of a thyroid storm just before a cesarean section occurred in a patient with several risk factors of thyroid storm and pulmonary edema, including pregnancy, treatment with tocolytic agents, and infection. The involvement of these multiple factors was considered to be the cause of the sudden onset of the thyroid storm and the cause of rapidly progressive pulmonary edema.

The platelet count, mean platelet volume, and other hematological parameters were compared in blood samples anticoagulated with MgSO 4 and EDTA. A total of 15 samples were taken, and the platelet counts were observed to be significantly high in MgSO 4 -anticoagulated blood samples ranging from 53 × 10 3 to 499 × 10 3 /µL, whereas in EDTA-anticoagulated blood samples, the counts ranged from 10 × 10 3 to 353 × 10 3 /µL. This increased platelet count was also statistically significant with the P value being .005. The morphology of red blood cells and white blood cells in Leishman-stained smears from MgSO 4 -anticoagulated blood was below average. In conclusion, MgSO 4 can be used as an alternative anticoagulant only to estimate the platelet counts in EDTA-induced pseudothrombocytopenia.

Aim of the experiment was evaluation of the effect of reduced calcium and magnesium content in the broiler chickens diet on its parameters of fattening, bone strength and calcium and magnesium content in liver. The trial was performed with cockerels of Ross 308 hybrid (n = 160) which were fattened in cage batteries from day 11th to 36th day of age. Cockerels were divided into 4 groups (differ in various intake levels of calcium and magnesium) in four replications. The maize-wheat-soybean basal diet contained 2.33 g Ca and 1.58 g Mg per kilogram. Calcium was added by CaCO3 and magnesium by MgSO4. Control group (C) received feed mixture with added CaCO3 in dose of 19.49 g.kg-1 and 0.41 g.kg-1 of MgSO4. Three experimental groups contain added CaCO3 in dose of 11.83 g.kg-1 and 0g.kg-1 MgSO4 (group Exp1); CaCO3 11.83 g.kg-1 and 0.41 g.kg-1 MgSO4 (group Exp2); CaCO3 19.49 g.kg-1 and 0g.kg-1 MgSO4 (group Exp3), respectively. The feed consumption was daily monitored and the cockerels were weighed twice a week. At the end of the study the experimental animals were weighted and slaughtered by decapitation. The weight of carcasses, liver and proportion of breast and thigh muscle was determined in the selected chickens (n = 24). The atomic absorption spectrometry was used for Ca and Mg evaluation in liver tissues. Bone strength parameter was measured at the femur bone. The statistically significant differences (p >0.05) were not detected between control and experimental groups in the case of studied parameters of fattening, bone strength and calcium and magnesium content in the chicken´s liver. Based on the obtained results it could be concluded the reduction of determined elements in the chicken diet did not deteriorate parameters of yield, elements content in liver tissue as well as the bone strength of broiler chickens.

Isopiestic (vapor pressure) measurements were made for aqueous mixtures of Mg(NO3)(2) and MgSO4 at T = (298.15 +/- 0.01) K with Mg(NO3)(2) ionic strength fractions y = (0.19691, 0.42542, 0.60113, 0.79583, and 1), along with a separate series of measurements for MgSO4(aq), y = 0, all using KCl(aq) as the reference standard. The resulting 44 molality-based osmotic coefficients for the ternary mixtures, ionic strength range I-m = (2.5924-8.4583) mol-kg(-1), were modeled with an extended form of Pitzer's ion interaction model, both with the usual Pitzer mixing terms and also with Scatchard's neutral electrolyte model mixing terms, and also with the Clegg-Pitzer-Brimblecombe model based on the mole-fraction-composition scale. The molality-based osmotic coefficients phi of these mixtures at each fixed ionic strength fraction fall in a regular order between those of the corresponding limiting binary solutions with no crossovers in this ionic strength range. Model parameters for Mg(NO3)(2)(aq) and MgSO4(aq) at T = 298.15 K needed for these calculations were evaluated by using the present isopiestic results along with other sets of reliable osmotic coefficients gleaned from the published literature. Our osmotic coefficients for the ternary system are compared with those from a previous isopiestic study and a hygrometric study and the present results were judged to be more accurate. For this ternary system, both mixing parameters are needed for the extended Pitzer model with Pitzer mixing terms {standard uncertainty of fit u(phi)= 7.0 x 10(-3)} whereas three parameters gave a significantly better fit when the Scatchard mixing terms are used {standard uncertainty of fit u(phi) = 4.0 x 10(-3); the fits with two Scatchard mixing parameters did slightly better than the fit with both Pitzer mixing terms}, as did the Clegg-Pitzer-Brimblecombe model with three mixing parameters {standard uncertainty of fit u(phi) = 5.9 x 10(-3)}, with use of the three Scatchard mixing parameters giving the most precise representation of the experimental results. Including higher-order electrostatic mixing terms did not improve the representations but had the opposite effect.

International audience; Study about magnesium sulfate − water vapor equilibrium proved to be very interesting especially on the use of dehydration-hydration reactions for the heat storage application in recent research. Heat is realized by hydration of lower hydrates as this reaction is exothermic. Therefore, reversible reaction, endothermic thermal dehydration of higher hydrates, is used for charging of system and in this state the energy can be stored over long time. Even if magnesium sulfate appears as promising candidate with high theoretical energy density of 2.8 GJ/m−3, technological process is rather complicated. The main problem that thermodynamic and kinetic data are poorly understood to present. In these study salt hydrates equilibrium of magnesium sulfate was investigated by new approach. It makes possible to understand the dehydration reaction of MgSO4·6H2O for heat storage application. Dehydration reaction under various water vapor pressures and temperatures were investigated by thermogravimetric analysis. The result showed that water content in the solid phase is a function of temperature for given water vapor pressure. So, we can conclude that this magnesium sulfate − water vapor system is bivariant and some hydrates appear as the non-stoichiometric hydrates.

Damask rose (Rosa damascena Mill.) is one of the most high-value essential oil-bearing plants in the world. However, the flower yield and quality of essential oil of R. damascena are largely influenced by the pruning practices and balanced supply of plant nutrition. The objective of this study was to test the hypothesis whether the pruning system and foliar fertilization of MgSO4 would influence the flower yield, growth and secondary metabolites profile of R. damascena. A field experiment of 10 treatment combinations comprising two pruning systems (complete and partial) and five levels of MgSO4 (water spray, MgSO4 @ 5.0g L-1, 10.0g L-1,15.0g L-1, and 20.0g L-1) was conducted. The experiment was conducted in randomized block design with factorial arrangement. Overall, the flower yield ranged from 503.66 to 1114.47 g bush-1, while oil content varied from 0.039 to 0.046% of the fresh flower. Irrespective of foliar spray, partial pruning produced significantly (P ≤ 0.05) higher flower yield (893.02 and 503.66 g bush-1) compared with complete pruning system in both the years. Regardless of pruning system, the foliar application of MgSO4 @ 15.0g L-1 registered about 26–38% higher flower yield compared with water spray control. The major constituents of essential oil were citronellol (19.75–48.88%), E-geraniol (9.63–29.6%), Z-citral (0.07–5.97%), nonadecane (6.76–22.32%), and heneicosane (2.87–10.21%). The principal component analysis revealed that the major hydrocarbons such as nonadecene, nonadecane, and heptadecane are positively and highly correlated with each others. The results suggest that higher yield and quality of R. damascena can be achieved through partial pruning system in combination with foliar application MgSO4 under rainfed acidic conditions.

ISBN: 9781510843240 - Thème: Kinetics; International audience; Renewable energies are regarded as one of solutions for reducing the consumption of fossil fuels and limiting the global warming increases. However, these sources are intermittent most of the time. Energy storage systems can allow to make compatible the supply and the energy demand both spatially and temporally. For example the available solar energy exceeds the domestic demand during summer but during winter the total heating demand exceeds the solar supply. So the main role of energy storage systems is to valorize the excess of solar energy in summer to fulfil the heat demand in the winter. Among the various technologies of heat storage, processes based on a reversible chemical reaction present the most important energy density. A large number of potentially interesting materials has been performed in the last decade. Among all these reactive solid/gas systems, the couple magnesium sulfate/water vapor is presented as the most promising candidate. However, the use of magnesium sulfate powder is difficult in a storage reactor because the particles rapidly form agglomerates during cycle dehydration/hydration, thus liming gas transfer and causing reversibility issues and low temperature lift. Therefore, system performance is consequently low. Composite materials developed by impregnation of a hygroscopic salt such as magnesium sulfate into a porous matrix appear as an interesting solution for the heat storage technology. This material allows reducing the problem of gas transfer and further to benefice the heat due to a chemical reaction upon the salt and the heat of adsorption upon the porous material. Composite of zeolite and magnesium sulfate shows the best performances, sufficient power for a low-energy building and good cyclability. However the development of such a system is technologically challenging, the main obstacle is the incomplete understanding of the physico-chemical phenomena involved. The present work reports the study of dehydration of magnesium sulfate and the mechanism of reaction poorly studied up to now. Dehydration of solid magnesium sulfate in a controlled atmosphere was monitored by thermogravimetry and physico-chemical characterizations have been realized. The results obtained from these experiments show that the water content in the solid phase of magnesium sulfate is a function of a temperature at a constant water vapour pressure. And at a constant temperature, the water content varies with a water vapour pressure. Thus this system is bivariant and some magnesium sulfate hydrates appear as the non-stoichiometric hydrates. This result is new compared to the literature review. In consequence a thermodynamic model has been written and applied to the experimental results. Also, we present a kinetic model allowed to report experimental data and to describe the laws of variation of parameters with the temperature and the partial pressure of water pressure.

kullanmıştır. Doğal taşlar, sıcaklık değişiklikleri, nem, tuz kristalizasyonu, donma vb. çeşitli doğal süreçlerin etkisiyle ayrışmaya maruz kalırlar. Tuzlar, tarihi yapılardaki gözenekli malzemelerin ayrışmasına neden olan en önemli faktörlerden biridir. Kireçtaşları, doğada bol bulunan ve çalışılması kolay taşlar olduğundan yüzyıllardır yaygın olarak kullanılan yapı malzemeleridir. Günümüzde kireçtaşları, hem modern binalarda ana malzeme olarak hem de süsleme ve kaplama malzemesi olarak kullanılmaktadır. Bu çalışmada, kireçtaşı ve mermer üzerinde tuzların etkileri incelenmiştir. Çalışmanın amacı, tortul ve metamorfik kökenli, Kırklareli-Pınarhisar’ın bol-iri fosilli, az fosilli, fosilsiz kalkerleri ile Marmara Beyazı mermerleri yapı taşlarındaki çözünür tuz kristalizasyonunun mekanizmasını belirlemektir. Test yöntemi, Building Research Establishment (BRE) standartlarının, yapı malzemeleri için kullandığı dayanıklılık deneyleridir. Deney süresince, kayacın yapısal değişimi, görünümleri ve örneklerdeki değişiklikler gözlenmiş ve örnek yüzeylerinde oluşan her renk değişimi kaydedilmiştir. Doğal ortam koşullarında oluşabilecek gerçek tuz miktarını temsil etmek amacıyla %1 ve %3 oranlarında Na2SO4 ve MgSO4 etkilerine maruz bırakılarak yapı taşının bozulma miktarı, bozulma şekli ve renk değişimi incelenmiştir. Çalışmanın sonucunda tortul kayaçların (kireçtaşı) ağırlık kaybının metamorfik kayaçların (mermer) ağırlık kaybından daha fazla olduğu belirlenmiştir, Mankind has always used stone as building material to create monuments and other structures through out history. Long period of time exposure to temperature changes, moisture, salt crystallization, and frost create damages and disintegration in natural stones. Salt deterioration is one of the most important factors causing weathering on porous materials in historical buildings. Since limestone is one of the most common building materials used for so many centuries, because the availability and easy to work on. Limestone nowadays is still used in modern buildings either as main structural material or decorative coating elements. In this study concentration is given to salt effects on limestone and marbe. The purpose of this study is to explain the mechanism of dissoluble salt crystallization in the building stones of the fossiliferous or non-fossiliferous limestones and Marmara white marble. The test method is the durability experiments which have been used for the building material according to Building Research Establishment (BRE) standards. In the experiments, the structural change of the rocks, their visual features and other modifications have been observed and the differentiation in the rock color has been noted. To examine the degree of decomposition, alteration type and the color change in the rocks, the samples, as a whole, are subject to the effect of solutions containing a bulk Na2SO4 and MgSO4 grade of 1.0 to 3.0 percent. The results show that the mass decrease of the limestones is higher than those of the marbles

travail. Résumé L’amphotéricine B est actuellement le traitement de référence des mycoses systémiques malgré sa toxicité vis-à-vis des cellules animales, qui est liée à son insolubilité en milieu aqueux. Pour cette raison diverses formulations lipidiques d’amphotéricine B ont été développées afin d’augmenter son index thérapeutique mais qui reste malheureusement trop onéreuse. Plusieurs stratégies ont été proposées pour améliorer l’index thérapeutique de l’amphotéricine B dont la modulation de l’environnement physico-chimique. Le pH de la solution joue un rôle important dans l’activité de cette molécule. C’est pourquoi nous avons étudié l’effet de l’action combinée du pH et des sels MgSO4 et MgCl2 sur la toxicité sélective de l’amphotéricine B envers les globules rouges humaines. Il ressort de notre travail que la présence des sels MgSO4 et MgCl2 réduit la toxicité de Fungizone® envers les globules rouges humaines mais cette réduction est beaucoup plus importante en présence de MgSO4 qu’en présence de MgCl2. A pH 5,4 la Fungizone® est moins toxique. Le taux d’hémolyse est réduit en présence de MgSO4 à concentration égale à 10-1M. Mots clés : Amphotéricine B, Fungizone®, toxicité sélective, pH, érythrocytes, MgSO4, MgCl2. Abstract Amphotericin B is currently the standard treatment of systemic fungal infections despite his vis-à-vis toxicity animal cells, which is related to its insolubility in aqueous medium. For this reason various lipid formulations of amphotericin B have been developed to increase the therapeutic index but which is unfortunately too expensive. Several strategies have been proposed to improve the therapeutic index of amphotericin B with the modulation of the physico-chemical environment. The pH of the solution plays an important role in the activity of this molecule. That is why we have studied the effect of the combined action of pH and MgSO4 and MgCl2 salts on selective toxicity of amphotericin B to human red blood cells. It is clear from our work that the presence of MgSO4 and MgCl2 salts reduces the toxicity of Fungizone® towards human red blood cells but this reduction is much greater in the presence of MgSO4 in the presence of MgCl2. At pH 5.4 the Fungizone® is less toxic. The hemolysis rate is reduced in the presence of MgSO4 concentration equal to 10-1M. Keywords: Amphotericin B, Fungizone®, selective toxicity, pH, erythrocytes, MgSO4, MgCl2. ملخص هى دبن بٍ انعلاج انق بٍس ي الانخهبببث انفطز تٌ انجهبس تٌ عهى انزغى ي س تًٍ خلا بٌ انذ ىٍا وجهب amphotéricine B ال نىجه، وانذي زٌحبظ إنى انذوبب ف وسظ يبئ .ً نش بٌدة يؤشز انعلاج ونك انذي هى نلأسف يكهفت amphotéricine B نهذا انسبب وضعج يخخهف انص غٍ انذهى ي ال نهغب تٌ. يع حعذ مٌ انب ئٍت انف شٍ بٌئ تٍ وانك بًٍٍئ تٍ. ال amphotéricine B وقذ اقخزدج عذة اسخزاح جٍ بٍث نخذس اليؤشز انعلاج لل نه ذًهىل حهعب دورا هبيب ف شَبط هذا انجشيء. pH ع س تًٍ MgCl و 2 MgSO هذا هى انسبب ف أ بَُ درس بُ حأث زٍ انع مً ان شًخزك ي درجت انذ ىًضت و الأيلاح 4 نخلا بٌ انذو انذ زًاء انبشز تٌ. amphotéricine B ال ذَى خلا بٌ انذو انذ زًاء ف الا سَب Fungizone® قٌهم ي س تًٍ MgCl و 2 MgSO و خٌضخ ي ع هً بُ أ وجىد الأيلاح 4 .MgCl و ف وجىد 2 MgSO ونك هذا انخخفضٍ هى أكبز بكث زٍ ف ظم وجىد 4 .10-1 M سٌبوي MgSO هى أقم س تًٍ. خٌى خفض يعذل ا ذَلال انذو ف وجىد حزك شٍ 4 Fungizone® ال pH ف 5,4 ،MgSO س تًٍ ا خَقبئ تٍ، درجت انذ ىًضت، انكز بٌث انذ زًاء، 4 ،Fungizone®، amphotéricine B كلمات البحث: ال .MgCl2

Kluyveromyces marxianus is a thermotolerant, crabtree-negative yeast, which preferentially directs metabolism (e.g., from the tricarboxylic acid cycle) to aerobic alcoholic fermentation. Thus K. marxianus has great potential for engineering to produce various materials under aerobic cultivation conditions. In this study, we engineered K. marxianus to produce and secrete a single-chain antibody (scFv), a product that is highly valuable but has historically proven difficult to generate at large scale. scFv production was obtained with strains carrying either plasmid-borne or genomically integrated constructs using various combinations of promoters (PMDH1 or PACO1) and secretion signal peptides (KmINUss or Scα-MFss). As the wild-type K. marxianus secretes endogenous inulinase predominantly, the corresponding INU1 gene was disrupted using a Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR)—associated protein (CRISPR–Cas9) system to re-direct resources to scFv production. Genomic integration was used to replace INU1 with sequences encoding a fusion of the INU1 signal peptide to scFv; the resulting construct yielded the highest scFv production among the strains tested. Optimization of growth conditions revealed that scFv production by this strain was enhanced by incubation at 30 °C in xylose medium containing 200 mM MgSO4. These results together demonstrate that K. marxianus has the potential to serve as a host strain for antibody production. Electronic supplementary material The online version of this article (10.1186/s13568-018-0588-1) contains supplementary material, which is available to authorized users.

Bu çalışma, prepartum dönemde sütçü inek rasyonlarına anyonik tuz (MgCl2 veya MgSO4) ilavesinin metabolik profil, peripartum hastalıklar ve gebelik oranı üzerine etkilerini belirlemek amacıyla yürütülmüştür. Kırk beş baş Holstein ırkı inek gebeliğin son 3 haftasından başlayarak vücut kondüsyon skorları benzer olan 3 gruba ayrılmıştır. Prepartum dönemde 21 gün süreyle, kontrol grubuna anyonik tuz içermeyen toplam karışım rasyon (TMR) yedirilirken, muamele gruplarından birine 30 g/gün/inek MgCl2, diğerine ise 30 g/gün/inek MgSO4 ilave edilen TMR verilmiştir. Postpartum dönemde tüm gruplar tek bir toplam karışım rasyonla beslenmiştir. Postpartum 30. günden sonra gruplardaki ineklere Presynch-Ovsynch senkronizasyon protokolü uygulanmış ve sabit zamanlı tohumlama yapılmıştır. Çalışma postpartum 8. haftada sonlandırılmıştır. Toplam karışım rasyon içerisine MgCl2 ilave edilen grupta, MgSO4 ilave edilen ve kontrol grubuna nazaran süt verimi artmıştır. Anyonik tuz ilavelerinin serum AST ve ALT konsantrasyonlarını azalttığı, serum glukoz, HDL, IgG, Ca ve Mg konsantrasyonlarını arttırdığı belirlenmiştir. Grupların sağlık ve üreme performanslarının benzer olduğu saptanmıştır. Sonuç olarak, prepartum dönemde TMR içerisine anyonik tuz ilave edilmesinin süt verimi ve kan biyokimyasında değişimlere yol açabileceği söylenebilir.

Introduction: Considering the high incidence of preterm labor and its known complications, and that human myometrium contains receptors for human chronic gonadotropin (hCG) and that hCG can inhibit myometrial contractions on vitro, made me study treating effects of hCG on preterm labor. This clinical trial study was carried out to compare the effect of hCG, and magnesium sulfate (mgso4) on prevention of preterm labor Materials and methods: The study group included 101 women at weeks 22-35 of the gestation with intact membranes and cervical dilatation less than 4cm in preterm labor in referrals of obstetric – clinics in Khorramabad city during the years 2001-2003. The case and control groups were treated with hCG protocol of the dosage consisted of one single dose of hCG 5000 1v and 10000 units of hCG in 5oo dextrose as a drip of 20 drops per minute. Treatment continued until preterm labor arrested and then complications of mother and fetus were recorded. On condition of a successful cease of labor, the patients were discharged and followed uptill deliven time. Findings: Both groups were similar to each other regarding maternal age, gravity, and gestational age . Mean delay of labor was 22/68 days after administration of hCG and 24/27 days for (mgso4) that was not significant. The number of newborns that admitted in NICU were 9 (18%) for hCG and were 9(17/8%) for magso4. Mean weight at labor was 2334gr and 2287gr for hCG and mgso4. The complaint rate was 100% and 0% for magnesium sulfate and hCG groups respectively (P

International audience; We study mutual diffusion of associated electrolyte in water. A theory based on the Smoluchowski equation and on the mean spherical approximation is proposed. It is found to be valid up to molar concentrations. The values of the association constant obtained for ZnSO4 and MgSO4 aqueous solutions are consistent with further methods of measurements. Thanks to the elimination of fast variables method, the theory can be generalised to any association in solution. Comparison with molecular dynamics and Brownian dynamics simulations in the case of MgSO4 indicates that the pair is a global association phenomenon since it corresponds to several association phenomena (contact ion pair and solvent separated ion pair).

We study hydrated magnesium sulfate minerals from first-principles calculations based on densityfunctional theory. We determine the heat of hydration for MgSO4\textperiodcenterednH2O, compute the Raman and infrared spectra for several phases and calculate the S isotope partitioning as a function of hydration. We find that epsomite and meridianiite with, respectively, n = 7 and n = 11 water molecules per MgSO4 unit are particularly stable with respect to other individual or combinations of hydration states. The Raman spectra of all phases present clear SO4 features that are easily identifiable. We use this to show one can use the vibrational spectroscopic information as an identification tool in a remote environment, like the martian surface. We discuss the character and atomic displacement pattern of all vibration modes and compute the 34S/32S partitioning; this work shows that hydration favors enrichment in the lighter S isotope 32S with respect to the heavier 34S, which is accumulated in the less hydrous structures. We show for the first time that the signature of 34S/32S partitioning could be observed by in situ spectroscopy on the surface of Mars. Moreover this can be related to the diurnal cycle of hydration and dehydration and hence it can improve the modeling of the water circulation on Mars.

Bu çalışmada pomza ve zeolit içeren yüksek dayanımlı betonun “YDB. MgSO4 çevresel etkisi altında rijit yol kaplaması olarak kullanılabilirliği araştırılmıştır. Bu kapsamda, üretilen beton için taze beton deneyleri, basınç dayanımı deneyi ve aşınma direnci deneyleri yapılmıştır. Üretilen betonda bağlayıcı olarak kullanılan çimento, pomza ve zeolit üzerinde fiziksel, kimyasal ve mekanik deneyler yapılmıştır. Yüksek dayanımlı beton “YDB. karışım dizaynı gerçekleştirilirken çimentoya ikame edilmek suretiyle sırasıyla %0 Pomza+%15 Zeolit (0P15Z), %5 Pomza+%10 Zeolit (5P10Z), %10 Pomza+%5 Zeolit (10P5Z) ve %15 Pomza+%0 Zeolit (15P0Z) olmak üzere dört tip YDB üretilmiştir. Sonuç olarak, MgSO4 çevresel etkisi altında kalan YDB’ların sadece yüzeylerinde “candlot tozu ve kalsiyum sülfoalimünat. gibi birtakım reaksiyon ürünleri oluşmuştur. Ancak betona zarar veren bu ürünlerin betonun merkezine doğru nüfuz edemediği görülmüştür. Diğer taraftan gözle görülebilir çatlak oluşmadığı, özellikle ilerleyen yaşlarda numunenin ayrıtlarında çok hafif kopmalar olduğu tespit edilmiştir. Aşınma dayanımı değerlerinin ise tüm beton türlerinde ASTM C944-99’de öngörülen değerlerin altında olduğu tespit edilmiştir. In this study, pumice and zeolite containing high-strength concrete under the environmental impact of MgSO4 as the availability of rigid pavement was investigated. In this context, experiments produced concrete for concrete, compressive strength and abrasion resistance tests were conducted. Physical, chemical and mechanical experiments have been made on the cement, pumice and zeolite which were used as binders in concrete High-strength concrete "HSC" cement mix design is being realized through the substitution to be 0% pumice + 15% Zeolite (0P15Z), 5% pumice + 10% Zeolite (5P10Z), 10% pumice + 5% zeolite (10P5Z) and 15% pumice +% 0 Zeolite (15P0Z) respectively. HSC to four types were produced. As a result, under the influence of environmental MgSO4 only the surfaces of the remaining HSC "candlot powder and calcium sulfoalimunat such as" some reaction products were formed. However, damage to concrete, these products were unable to penetrate toward the center of the concrete. On the other hand does not create visible cracks, especially in later times in the edges of the sample was found to be of very light break. Abrasion resistance of concrete values for all types of the predicted values under ASTM C944-99 that have been determined.

Apresentação efetuada nos Seminários de Física, Universidade do Minho, 2013, We use classical atomistic molecular dynamics simulations and polarizable models to investigate the dynamics of rotation of room temperature water in the vicinity of magnesium sulfate ions. At infinite Mg2+-SO4 2- separation, both ions strongly slow down the rotation of water in their first hydration shell but only weakly affect molecules in their second hydration shell. At 12 Å Mg2+-SO4 2- separation, a small population of water molecules halfway between the ions rotates more slowly than the equivalent population near the isolated ions, indicating that pairs of anions and cations slow down water rotation in a cooperative manner. Surprisingly, this subpopulation consists exclusively of water molecules in the second or third hydration layers of either ion. In contrast, for a 5 Å Mg2+-SO4 2- separation intense cooperative slowdown of water rotation is observed in the first hydration layer of each ion, and much weaker effects are present in the outer hydration layers. For both small and large Mg2+-SO4 2- distances, cooperative slowdown is larger in multi-ion systems than in systems with a single pair of ions. Our results broadly support the existence of long-range cooperative slowdown of water rotation by ions, initially proposed based on experimental measurements (Tielrooij et al., 2010, Science, 328, 1006), but reveal a much more complex picture of the effect. The dependence of cooperative slowdown on the anion-cation distance, ion concentration and the position of water molecules relative to the ions obtained from simulations can be used to refine the interpretation of experimental measurements to obtain further insight into these systems., Max Planck institute for colloids and interfaces, Golm, Alemanha

Apresentação efetuada no Computer Simulation and Theory of Macromolecules, Hunfeld, 2013, Max Planck institute for colloids and interfaces, Golm, Alemanha

To evaluate and compare the effectiveness of magnesium sulfate (MgSO4) and mannitol in the treatment of posterior reversible encephalopathy syndrome (PRES) in eclamptic women. This retrospective analysis includes 62 eclamptic women between 22 and 40 weeks of gestation who were diagnosed with PRES in a tertiary care center. To treat neurological symptoms, 34 women received magnesium sulfate (Group 1) and the remaining 28 received 20% mannitol (Group 2) at the discretion of treating physician. Ten patients from both Group 1 (29%) and Group 2 (35.7%) were normotensive at admission. 59 of 62 patients presented with seizure. All patients underwent fluid attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI). Parietooccipital region and cerebellum were the most commonly affected areas. The duration of treatment was significantly shorter in Group 1 than Group 2 (p < 0.001). Neurological examinations and the recovery after treatment were significantly better in favor of MgSO4 group (p = 0.039). Mannitol is not superior to magnesium sulfate in achieving neurological recovery. Magnesium sulfate seems to be the agent of choice for treatment of PRES.

Purpose: The plant, Cinnamomum zeylanicum (Laureceae), is a small, ever green plant which is native to southern India and it has been reported to possess a number of medicinal properties. The purpose of the present study was to evaluate the anti-diarrhoeal activity of the aqueous extract of the bark of Cinnamomum zeylanicum which is used traditionally as folk medicine, by using a castor oil and MgSO4 (Magnesium Sulphate) induced diarrhoea model. Methods: The aqueous extract of the bark of this plant at graded doses (100mg/kg, 200mg/kg body weight) was investigated for its anti-diarrhoeal activity in terms of the reduction in the rate of defaecation and the consistency of faeces in castor oil, Mgso4 induced diarrhoea. To understand the mechanism of its antidiarrhoeal activity, its effect was further evaluated on the gastrointestinal transit time with charcoal meal. Results: The bark extract showed significant (p

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2005, Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2005, Birçok bor kimyasalının üretiminde kullanılan borik asit, Türkiye’de ve Avrupa’da, kolemanitin sülfürik asit ile reaksiyonu sonucu üretilmektedir. Reaksiyon 80-102C arasında gerçekleşebilmekte ve oluşan yan ürün jipsin filtrasyonu yapıldıktan sonra sıcak berrak çözelti soğutularak borik asit kristallendirilmektedir. Kolemanitten sülfürik asit kullanımı ile borik asit üretiminde karşılaşılan en önemli sorun, cevherdeki magnezyumlu bileşiklerin kullanılan asitle reaksiyona girerek çözeltide çözünürlüğü çok yüksek olan MgSO4 oluşturmasıdır. MgSO4’ün prosesten hiçbir doğal çıkışı olmadığından; MgSO4 konsantrasyonu prosesten çözelti atılması ile dengelenmekte, bu çözelti kaybı ise proses veriminin önemli ölçüde düşmesine neden olmaktadır. Ticari borik asit kristallerinde sülfat miktarının 150 ppm’den az olması istenmektedir ve gelecek yıllarda bu değerin 50 ppm’in altına düşmesi beklenmektedir. Yüksek verimli ve düşük sülfat içerikli borik asit üretimi için ise sisteme giren magnezyumun düşük değerde tutulması gerekmektedir. Borik asit çözeltilerine magnezyum geçtikten sonra alınabilecek önlemler sınırlıdır ve ekonomik olarak en uygun çözüm, çözeltiye minimum miktarda magnezyum geçişini sağlamaktır. Bu nedenle bu çalışmada, zayıf bir asit olan ve kolemanit cevherindeki kil minerallerine etki etmeyen propiyonik asit kullanımıyla sisteme giren magnezyum miktarının azaltılıp azaltılamayacağı, değişik konsantrasyonlardaki sülfürik asit-propiyonik asit karışımları ile kolemanit cevheri reaksiyona sokularak araştırılmıştır. Deneyler kesikli reaktörde yürütülmüş ve reaksiyonun ilerleyişi iletkenlik ölçülerek sürekli takip edilmiş ve kimyasal analizlerle desteklenmiştir. Reaksiyon için kullanılan asit karışımındaki propiyonik asit oranındaki artmanın reaksiyon hızını kısmen düşürdüğü, çözeltiye geçen magnezyum konsantrasyonunun ise azalttığı belirlenmiştir., Boric acid is produced in Turkey and Europe mainly by the reaction of colemanite with sulfuric acid leading to crystallization of gypsum. The reaction can be carried out at 80-102C. Gypsum is removed by filtration and boric acid is crystallized by cooling the filtrate. The most important problem in boric acid production from colemanite ores with H2SO4 is the formation of MgSO4 coming from the gang mineral (magnesium borat and clay minerals). The amount of MgSO4 is balanced by the discharge of the solution from the process and this leads to decrease the efficiency of the process. It is desired that the amount of sulfate should be smaller than 150 ppm in the commercial boric acid crystals. It is expected that it will be smaller than 50 ppm in the near future. Therefore the inlet amount of magnesium should be kept in low level in high recovery process. The precautions are limited when magnesium concentration reaches a certain level in the solution. The most appropriate solution is to achieve the minimum magnesium inlet to the solution. For this reason, in this study, the accumulation of magnesium impurity will be controlled by the use of propionic acid which does not decompose the clay minerals. The reaction of colemanite with varying sulfuric acid-propionic acid mixtures has been investigated. The experiments have been carried out in a batch reactor and the progress of the reactions has been determined by measuring the conductivity and the results were supported by the chemical analysis. It was found that the dissolution rate and the amount of magnesium passing into the solution decreases with increasing propionic acid concentration in prepared acid mixtures for the reactions., Yüksek Lisans, M.Sc.

U radu je ispitivan utjecaj amorfnog SiO2 na otpornost cementnog morta i tijek korozijskih procesa prema djelovanju agresivnog okoliša sulfatnih iona mjerenjem promjena mehaničkih čvrstoća i promjena volumena uzoraka uslijed bubrenja, te određivanjem promjena modula elastičnosti u određenim vremenskim intervalima. Ispitivanja su provedena na cementnim mortovima pripremljenim od industrijskog portland cementa tipa CEM II-S 42, 5, oznake PC30z45s uz zamijenski dodatak filtarske SiO2 prašine od 0, 2, 5, 8, 11 i 15 mas. %. Mort na bazi sulfatno-otpornog cementa upotrebljen je kao referentni uzorak. Radi usporedbe dobivenih rezultata, uzorci morta bez i s dodatkom filtarske SiO2 prašine su istovremeno tretirani u vodovodnoj vodi. Rezultati ispitivanja otpornosti mortova u agresivnoj otopini MgSO4 (masene koncentracije od 25000 mg/L) pokazali su da su uzorci s većim dodatkom filtarske SiO2 prašine (iznad 8 mas.%)otporniji prema korozijskom djelovanju magnezijevog sulfata. Ovi uzorci manje bubre čak i od referentnog uzorka na bazi sulfatno-otpornog cementa. Uzorak bez dodatka filtarske SiO2 prašine raspao se poslije 60 dana boravka u otopini MgSO4 kao posljedica bubrenja zbog velike količine gipsa i etringita, što je potvrđeno rendgenskom difrakcijskom analizom, te TEM istraživanjima. Dobivena matematička ovisnost Ed =f(C), koja povezuje dinamički modul elastičnosti(Ed) s tlačnom čvrstoćom (C) mortova bez i s dodatkom SiO2 prašine dobro slijedi Britanski standard za beton, B.S. CP 100-72.