Journal of Advanced Concrete Technology
·
2022
·Vol. 20
·期 3
·212-221
·
IF 2.459
Xiaoyuan Zhang,Chengyou Wu
Basic magnesium sulfate cement (BMSC) is a new type of gas-hardening magnesium cementitious material. In this study, basic magnesium carbonate was used as the raw material to obtain different active magnesium oxides by calcination at different temperatures to prepare BMSC with MgO:MgSO4:H2O = 5:1:20. The effect of different active magnesium oxides and different mineral admixtures and their content on the compressive strength of BMSC before and after soaking was analyzed, and the influence of MgO activity on the water resistance of BMSC was explored. The experimental results show that the activity of MgO has a significant impact on the water resistance of BMSC, and the water resistance of BMSC prepared from low-activity MgO is better, mainly because the hydration products of BMSC prepared by low-activity MgO are 5•1•7 phases. The MgSO4 in the 5•1•7 phase is insoluble in water; consequently, the free MgSO4 in BMSC is scarce; thus, the phase remains unchanged. After selecting low-activity MgO (T1000) and adding mineral admixtures to study its water resistance, it was found that the BMSC softening coefficient increases with an increase in the mineral admixture content. Both fly ash and silica fume were found to improve the water resistance of BMSC and increase its water resistance.
研究领域:
建筑材料学
·
无机材料科学
✓ 已验证
产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2020
·
IF 4.419
Yongshan Tan,Hongfa Yu,Shikuan Sun,Chengyou Wu,Hao Ding
Silica fume (SF) as an important supplementary cementitious material has been widely used in Portland cement, but few published articles have reported on the effect of SF on the performance and hydration mechanism of basic magnesium sulfate cement (BMSC). In the present work, the properties, microstructure and hydration mechanism of BMSC influenced by SF was studied systematically. The results show that the setting time and compressive strength of BMSC may increase with the increase of SF content, while the hydration heat will decrease with the increase of SF content. Mercury intrusion porosimetry (MIP), X-ray computed tomography (X-CT), scanning electron microscope- Energy dispersive spectrometer (SEM-EDS) results show that SF exhibits filling effect in the BMSC matrix, which makes the microstructure of BMSC matrix with SF more compact. In addition, solid-state magnetic resonance (NMR) and SEM-EDS analysis indicate that the activity of SF was excited in the BMSC matrix, resulting in the formation of M−S−H gel.
研究领域:
材料科学
·
土木工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2022
·
IF 7.693
Xiaoyuan Zhang,Huifang Zhang,Chengyou Wu
Magnesium hydroxide was calcined at different temperatures to prepare different active magnesia, and 3% and 5% B was added to the magnesia precursor to prepare basic magnesium sulfate cement (BMSC). The phase composition of the hydration products and the development of the pore structure were analysed to investigate the effect of the salt lake coexisting B impurity on the performance of BMSC. The results showed that the hydration rate of the BMSC prepared by adding B is slower, the setting and hardening times were longer, and the compressive strength was lower than those of the control group. Furthermore, B significantly affected the early compressive strength of the BMSC prepared using high-activity magnesium oxide. Mainly because the specific surface area of the magnesia calcined at a low temperature (700 °C) increased, the crystal grain size reduced, the degree of crystallinity reduced, and the number of internal defects increased. In the case of the magnesia obtained by calcining at a high temperature (1000 °C) and adding boric acid, a large number of rough magnesium borate complexes were formed on the surface, and the adjacent magnesium oxide continuously agglomerated and underwent sintering, which improved the degree of crystallinity and reduced the number of internal defects.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Yaoshan Li,Yuan Liu,Yuwei Cao,Huatai Wang,Kaitao Li,Yanjun Lin
In this study, the solubility of anhydrous magnesium sulfate (MgSO 4 ) in ethanol solutions with concentrations ranging from 10 % to 50 % was determined at 15–50 °C. Next, the results were correlated by using the Apelblat model, polynomial empirical equation, ideal solution equation of state model, and Van’t Hoff–Jouyban–Acree model. The results indicated that all four models exhibited correlation coefficients greater than 97 %, and average relative deviations of 3.82 %, 4.24 %, 3.96 %, and 3.96 %, respectively. Notably, the Apelblat model was found to be more accurate and reliable in correlating the solubility of MgSO 4 in ethanol solutions with different concentrations. Further, the Van’t Hoff equation was applied to determine the enthalpy and entropy of dissolution. Herein, a certain amount of anhydrous ethanol was added to the zinc (Zn) electrolytic waste solution (ZEWS) to crystallize Zn 2+ and Mg 2+ through the solvent crystallization method, with the precipitation rates reaching 20.13 % and 39.38 %, respectively. The concentration of Mg 2+ reduced to below 15 g⋅L −1 , meeting the quality standard of ZEWS. The XRD, TG, and SEM analyses of the output salt mix crystallization confirmed the primary components to be MgSO 4 ·7H 2 O and ZnSO 4 ·7H 2 O, with the morphological features primarily consisting of short rods and some crystal agglomerates. This study shows that the removal of Mg 2+ from Zn smelting process can be effectively achieved by the proposed solvent crystallization method.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
Minerals
·
2023
·Vol. 13
·期 3
·318
·
IF 2.5
Yingli Chen,Xiyun Yang,Linglong Wu,Lirong Tong,Jing Zhu
This paper describes a leaching-purifying-precipitation process to recover magnesium from serpentine acid-leaching solution and to synthesize high purity Mg(OH)2and 4MgCO3·Mg(OH)2·4H2O. Fe, Al, and Cr in the leaching solution were removed using the oxidation precipitation method with active MgO as a precipitant and H2O2as an oxidant. Ni, Co and Mn were removed by Na2S precipitation to obtain a pure MgSO4solution. Mg2+ions were first precipitated with NH3·H2O to synthesize Mg(OH)2, followed by NH4HCO3precipitation to obtain 4MgCO3·Mg(OH)2·4H2O. A small part of MgSO4coprecipitates with Mg(OH)2to form MgSO4·5Mg(OH)2·3H2O. The Mg(OH)2was aged with a diluted NaOH solution to remove the sulfur; the two-stage precipitation percentage of Mg is 96.3%. Mg(OH)2has a purity of 98.48% with a sulfur content of 0.28%. This process provides a promising method for the high-efficiency recovery of Mg and the large-scale production of the high purity of Mg(OH)2from the serpentine.Keywords:serpentine;two-stage counter current leaching;remove impurity;MgSO4·5Mg(OH)2·3H2O;high purity Mg(OH)2
研究领域:
冶金工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 14
·8792-8803
·
IF 4.036
Shi-Jie Li,Xiang-Yu Yang,Li-Sheng Deng,Yong-Chun Fu,Ming-Jun Pang,Ti Dong,Yi-Song Yu,Ling-Na Su,Shang Jiang
In this research, the core objective is to explore the effect of super-absorbent polymer material (poly(sodium acrylate)) on the heat storage performance of magnesium sulfate and to investigate the heat transfer behavior of 13X-zeolite, nano-aluminum oxide (nano-Al2O3) and poly(sodium acrylate) modified magnesium sulfate in a reactor. Finally it provides support for future material and reactor design. All characterizations and performance tests were done in the laboratory and a numerical simulation method was used to investigate the heat transfer behavior of the reactor. Through hydrothermal treatment, bulk MgSO4·6H2O was changed into nanoparticles (200–500 nm) when composited with poly(sodium acrylate), 13X-zeolite and nano-Al2O3. Among these materials, MgSO4·6H2O shows the highest activation energy (36.8 kJ mol−1) and the lowest energy density (325 kJ kg−1). The activation energy and heat storage energy density of nano-Al2O3 modified composite material MA-1 are 28.5 kJ mol−1 and 1305 kJ kg−1, respectively. Poly(sodium acrylate) modified composite material, MPSA-3, shows good heat storage energy density (1100 kJ kg−1) and the lowest activation energy (22.3 kJ mol−1) due its high water-absorbing rate and dispersing effect. 13X-zeolite modified composite material MZ-2 shows lower activation energy (32.4 kJ mol−1) and the highest heat storage density (1411 kJ kg−1), which is 4.3 times higher than that of pure magnesium sulfate hexahydrate. According to the heat transfer numerical simulation, hygroscopic additives could prominently change the temperature distribution in the reactor and efficiently release heat to the thermal load side. The experimental and numerical simulation temperatures are similar. This indicates that the result of the numerical simulation is very close to the actual heat transfer behavior. This reactor could output heat at around 50 °C and absorb heat in the range of 100–200 °C. All these results further prove the strategy that thermochemical nanomaterial synthesis technology combined with material-reactor heat transfer numerical simulation is feasible for future material and reactor design.
研究领域:
材料科学
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能源工程
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
American Journal of Translational Research
·
2025
·Vol. 17
·期 3
·2005
·
IF 1.6
Xiaolan Zhuang,Xingxing Li,Shikai Yu,Lin Zeng,Yuping Xu,Tingting Hu,Sailong Wan
Objective: This study aimed to evaluate the clinical efficacy of labetalol (LBT) combined with magnesium sulfate (MgSO 4 ) in improving symptoms and pregnancy outcomes in patients with hypertensive disorders of pregnancy (HDP). Methods: A total of 122 HDP patients admitted between January 2020 and June 2024 were included. Among them, 56 patients (control group) received MgSO 4 alone, while 66 patients (research group) received a combination of LBT and MgSO 4 . Comparative analyses were conducted to evaluate therapeutic effectiveness, symptom improvement (edema, hypertension, and proteinuria), brain-related symptoms (nausea and vomiting, sluggishness, blurred vision, dizziness, and headache), pregnancy outcomes (placental abruption, neonatal asphyxia, fetal distress, and postpartum hemorrhage), blood pressure indicators (systolic (SBP) and diastolic blood pressure (DBP)), fetal umbilical artery hemodynamics (systolic-to-diastolic flow velocity ratio (S/D) and pulsatility index (PI)), and high-sensitivity C-reactive protein (hs-CRP). Results: The research group demonstrated significantly better outcomes than the control group, including a higher overall therapeutic effectiveness rate, faster resolution of edema, hypertension, and proteinuria, a lower incidence of adverse pregnancy events, and more pronounced reductions in SBP, DBP, S/D, PI, and hs-CRP levels after treatment (all P < 0.05). Conclusion: The combination of LBT and MgSO 4 is highly effective in improving symptoms and pregnancy outcomes in HDP patients, outperforming MgSO 4 monotherapy. This approach has strong potential for broader clinical application.
研究领域:
妇产科学
·
药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials
·
2024
·Vol. 17
·期 15
·3628
·
IF 3.1
Yuxiao Wu,Peini Shi,Qingsong Yang,Na Zhang
As one of the raw materials of basic magnesium sulfate cement (BMSC), the activity of light-burned magnesium oxide (MgO) has an important effect on the hydration rate, hydration products, and mechanical properties of BMSC. To reveal the influence of packaging method, storage environment, and storage time on the activity of MgO and the mechanical properties of BMSC, an experiment was conducted by using ordinary woven bags, peritoneal woven bags, and plastic and paper compound bags to store the finished BMSC and the raw materials (light-burned MgO, MgSO4·7H2O, fly ash, and a chemical additive) under the conditions of natural environment, sealed environment, and wet environment, respectively. Comparative analysis of the effects of packaging method, storage conditions, and storage time on the activity of MgO and the mechanical properties of BMSC was performed through the mechanical strength test of mortar specimens. The results showed that in a sealed environment, the loss of a-MgO content in light-burned MgO was minimized, which was more conducive to keeping the mechanical properties of BMSC stable. In the wet environment, the mechanical strength of BMSC was significantly reduced in the early stage (1 day) due to the significant reduction in the activity of MgO, and the mechanical strength of the finished BMSC and prepared BMSC after 120 days of storage was still lost, regardless of the packaging method. However, the storage environment and packaging method had relatively little effect on the late mechanical strength (28 days) of BMSC. It is advisable to use ordinary woven bags for packaging in natural and sealed environments as this is more economical for engineering applications. Plastic and paper compound bags are superior to ordinary woven bags and peritoneal woven bags in wet environments.
研究领域:
建筑材料学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY
·
2023
·
IF 9
Yige Hu,Hang Wang,Hu Chen,Yang Ding,Changtian Liu,Feng Jiang,Xiang Ling
Magnesium nitrate hexahydrate (MNH) was considered as a promising medium- and low-temperature phase change material (PCM) owing to high latent heat, weak corrosion, and low price. While supercooling performance greatly restricted the application of such PCM. In this work, MNH-based composite PCM containing a novel nucleating agent was prepared. Supercooling behavior and thermophysical properties of composites were analyzed. Additionally, thermal performance of composites in a fin-plate heat storage unit was investigated. Results showed that 2 wt% magnesium sulfate heptahydrate (MSH) effectively suppressed supercooling performance and was chemically compatible with MNH. Composites containing 2 wt% MSH and 2 wt% sodium carboxymethyl cellulose (CMC) performed favorable thermal properties, including supercooling degree of 0.6 °C, phase change temperature of 89 °C, latent heat of 166.88 J/g, and heat storage density of 220.78 J/g. Effective working temperature of the composite should be no more than 140 °C. Magnesium sulfate tetrahydrate (MST) was actually the real component in MSH that inhibited the supercooling of MNH. Compared with paraffin, encapsulated MNH-based composite PCM with a 6720 kJ higher heat storage capacity possessed a much shorter charging/discharging time due to the higher thermal conductivity . The results might provide a foundation for the practical application of MNH.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2025
·
IF 7.2
Jiaxin Pan,Xiaowei Huang,Longsheng Zhao,Depeng Liu,Ting'an Zhang,Zongyu Feng
The investigation of the leaching mechanisms of ion adsorption rare earth ores (IAREO) using MgSO 4 is significantly hindered by the complex mineral composition. In this study, the direct analogue of the natural IAREO sample, Y-kaolinite, was prepared and used to investigate the leaching mechanisms of rare earths from kaolinite under varying initial MgSO 4 concentrations and pH. The results of X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray absorption fine structure (XAFS) data indicate that the Y-kaolinite prepared exhibits a similar composition, micromorphology and coordination structure with nature IAREO sample. The coordination number and bond length of Y–O are 9.2±1.4 and 0.23±0.010 nm, respectively. The results of batch desorption experiments and sequential chemical extractions show that lowering the initial pH from 5.00 to 2.00 significantly enhances the desorption of rare earths from Y-kaolinite. Specifically, the additional desorption amounts are 0.52 mmol/kg for inorganic hydroxy Y (Hy-Y) and 0.40 mmol/kg for ion-exchangeable Y (Ex-Y). The enhancement mechanism was revealed by density functional theory (DFT) and Visual MINTEQ. The desorption of Hy-Y and Ex-Y is directly and indirectly enhanced by hydrogen ions, respectively. The desorption of Hy-Y is consistent with the dissolution behavior of the Y hydroxyl compound at lower pH. The desorption of Ex-Y is promoted by [Al(H 2 O) 6 ] 3+ released from Hy-Al by hydrogen ions. Additionally, when the concentration of MgSO 4 is 100 mmol/L and initial pH is 2.00, the desorption rate of rare earths is 87.1%, while the adsorption rate of magnesium is 63.1% and the stoichiometry ratio of Y 3+ to Mg 2+ is 1.04, which indicates that adequate hydrogen ions reduce the consumption of MgSO 4 and enhance the leaching of rare earth. These finding provide valuable insights into optimizing the selective leaching of rare earths from IAREO.
研究领域:
地球科学
·
矿物加工
·
环境化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Wan-Long Li,Xiao-Wei Luo,Wan-Ting Lin,Si-Yuan Zhang,Zi-Lu Zhang,Zi-Jun Zhang,Zhi-Kang Xu,Ling-Shu Wan
Traditional polyamide nanofiltration (NF) membranes are not applicable to high-temperature separation because of insufficient thermal stability. Modulation of the interfacial polymerization process is effective in improving the high-temperature separation performance of NF membranes. Herein, we introduce an interfacial polymerization strategy modulated with acid acceptors to prevent HCl, a byproduct in interfacial polymerization, from protonating amine monomers, and hence increase the compactness and thermal stability of the polyamide selective layers. The thickness, water contact angles, and charge properties were investigated. The optimized NF membranes show high-temperature separation performance with 97.7 % rejection to MgSO 4 and 24.4 L·m −2 ·h −1 ·bar −1 of permeance at 85 °C. The membranes also exhibit thermally stable separation performance at different salt concentrations, applied pressure, cycling temperature variations, and 100-h long-term operations. This study presents an inspiring method for preparing thermostable polyamide membranes.
研究领域:
膜科学
·
高分子化学
·
分离技术
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2022
·
IF 9.794
Xue Mu,Chuankai Fu,Renlong Li,Chunyu Du,Yunzhi Gao,Geping Yin,Pengjian Zuo
Silicon oxide (SiO x ), consisting of nanosized Si crystallites and oxide matrix (SiO y , y near 2), is regarded as one of the most promising anode materials for next-generation high energy density lithium-ion batteries (LIBs). Commonly, modulating oxygen content and surface chemistry are favorable to the lithium ions storage performances of SiO x anode. Here, an AlCl 3 –MgSO 4 assisted low-temperature (250 °C) etching technique is adopted to modify the commercial micron-sized SiO x anode, this novel modification method tunes the O/Si ratio on the surface of SiO x . Impressively, the modified SiO x anode exhibits a high reversible capacity of 480 mAh g −1 at 1A g −1 after 200 cycles and good rate capability of above 110 mAh g −1 at 10 A g −1 . This work provides a simple and feasible modification strategy to the development of high performance SiO x anode.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
电池技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）