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Microstructure of β-Dicalcium Silicate after Accelerated Carbonation 被引量:1
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作者 LIU Songhui ZHANG Haibo 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第1期122-126,共5页
The present work presents the microstructure of β-Ca_2SiO_4(β-C_2S) after accelerated carbonation. The synthesis procedure of β-C_2S was examined first, and the crystalline and amorphous structure, the distribution... The present work presents the microstructure of β-Ca_2SiO_4(β-C_2S) after accelerated carbonation. The synthesis procedure of β-C_2S was examined first, and the crystalline and amorphous structure, the distribution and the pore structure of β-C_2S carbonation products were also determined by X-ray diffraction(XRD) quantitative analysis, simultaneous thermal analyzer(TG/DTA), Fourier transform-infrared spectroscopy(FT-IR), high resolution ^(29)Si magic angle spinning nuclear magnetic resonance(^(29)Si NMR), N_2-sorption techniques, and scanning electron microscopy(SEM), respectively. Test results indicate that carbonation products are dramatically formed in the initial 2 h. The main carbonation products are crystalline calcite and amorphous three-dimensional network silica gels, which contain nanometer-sized pores. The calcite, silica gels and un-carbonated β-C_2S are distributed hierarchically. 展开更多
关键词 dicalcium silicate CARBONATION silicA GELS NANOMETER SIZE pores
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Effect of inorganic salt impurities on seeded precipitation of silica hydrate from sodium silicate solution
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作者 Xiao-bin LI Xiao-bing GAO +5 位作者 Qiu-sheng ZHOU Yi-lin WANG Tian-gui QI Lei-ting SHEN Gui-hua LIU Zhi-hong PENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期3016-3028,共13页
To clarify the precipitation of silica hydrate from the real desilication solutions of aluminosilicate solid wastes by adding seeds and improve integrated waste utilization,the seeded precipitation was studied using s... To clarify the precipitation of silica hydrate from the real desilication solutions of aluminosilicate solid wastes by adding seeds and improve integrated waste utilization,the seeded precipitation was studied using synthesized sodium silicate solution containing different inorganic salt impurities.The results show that sodium chloride,sodium sulfate,sodium carbonate,or calcium chloride can change the siloxy group structure.The number of high-polymeric siloxy groups decreases with increasing sodium chloride or sodium sulfate concentration,which is detrimental to seeded precipitation.Calcium chloride favors the polymerization of silicate ions,and even the chain groups precipitate with the precipitation of high-polymeric sheet and cage-like siloxy groups.The introduced sodium cations in sodium carbonate render a more open network structure of high-polymeric siloxy groups,although the carbonate ions favor the polymerization of siloxy groups.No matter how the four impurities affect the siloxy group structure,the precipitates are always amorphous opal-A silica hydrate. 展开更多
关键词 ALUMINOsilicate sodium silicate solution siloxy group IMPURITY silica hydrate
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Natural Silicate as a Solid Support for the Calix[4]Thiophosphorus Derivative for Removal Mercury (II), as Picrate from Water
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作者 Walther B. Aparicio-Aragon Tania Deza-Ramos 《Advances in Chemical Engineering and Science》 CAS 2024年第2期74-83,共10页
Currently a technique widely used for gold extraction is mercury by amalgamation technique, the tailing produced pollutes water of all kinds, so it is necessary to develop a form of selective mitigation, for which it ... Currently a technique widely used for gold extraction is mercury by amalgamation technique, the tailing produced pollutes water of all kinds, so it is necessary to develop a form of selective mitigation, for which it is necessary to use complexing agents based on calixarene functionalized with mercury sequestering agents. These are immobilized by adding supports based on natural silica to form polymers and make them insoluble in all types of solvents, so that they can be used as an extractor and at the same time regenerate to their original properties for continuous reuse. 展开更多
关键词 Extraction AMALGAMATION Polymer Natural silicate CALIXARENE
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Carbonation of Dicalcium Silicate Enhanced by Ammonia Bicarbonate and Its Mechanism
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作者 周浩 刘鹏 +1 位作者 WANG Fazhou HU Chuanlin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期69-74,共6页
The strength development law of γ-type dicalcium silicate (γ-C_(2)S) under different carbonation processes was investigated,and the carbonation mechanism of γ-C_(2)S under the action of NH_(4)HCO_(3) was clarified ... The strength development law of γ-type dicalcium silicate (γ-C_(2)S) under different carbonation processes was investigated,and the carbonation mechanism of γ-C_(2)S under the action of NH_(4)HCO_(3) was clarified by using a wide range of test methods,including XRD and SEM.A method of saturated NH_(4)HCO_(3) solution as a curing agent was identified to improve the carbonation efficiency and enhance the carbonation degree of γ-C_(2)S,and then a high-strength carbonated specimen was obtained.Microhardness analysis and SEM morphology analysis were conducted on the carbonised specimens obtained under atmospheric pressure carbonisation conditions using the curing agent.It was found that γ-C_(2)S could perform carbonisation well under atmospheric pressure,which promoted the carbonisation efficiency and decreased the carbonisation cost simultaneously.Therefore,a new carbonisation process solution was proposed for the rapid carbonisation of γ-C_(2)S. 展开更多
关键词 type dicalcium silicate carbonization process curing agent atmospheric carbonization
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Synergistic strengthening mechanism of Ca^(2+)-sodium silicate to selective separation of feldspar and quartz
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作者 Bo Lin Jingzhong Kuang +3 位作者 Yiqiang Yang Zheyu Huang Delong Yang Mingming Yu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第9期1985-1995,共11页
Inhibitors are important for flotation separation of quartz and feldspar.In this study,a novel combined inhibitor was used to separate quartz and feldspar in near-neutral pulp.Selective inhibition of the combined inhi... Inhibitors are important for flotation separation of quartz and feldspar.In this study,a novel combined inhibitor was used to separate quartz and feldspar in near-neutral pulp.Selective inhibition of the combined inhibitor was assessed by micro-flotation experiments.And a series of detection methods were used to detect differences in the surface properties of feldspars and quartz after flotation reagents and put forward the synergistic strengthening mechanism.The outcomes were pointed out that pre-mixing combined inhibitors were more effective than the addition of Ca^(2+)and SS in sequence under the optimal proportion of 1:5.A concentrate from artificial mixed minerals that was characterized by a high quartz grade and a high recovery was acquired,and was found to be 90.70wt% and 83.70%,respectively.It was demonstrated that the combined inhibitor selectively prevented the action of the collector and feldspar from Fourier-transform infrared(FT-IR)and adsorption capacity tests.The results of X-ray photoelectron spectroscopy(XPS)indicated that Ca^(2+)directly interacts with the surface of quartz to increase the adsorption of collectors.In contrast,the chemistry property of Al on the feldspar surface was altered by combined inhibitor due to Na^(+)and Ca^(2+)taking the place of K^(+),resulting in the composite inhibitor forms a hydrophilic structure,which prevents the adsorption of the collector on the surface of feldspar by interacting with the Al active site.The combination of Ca^(2+)and SS synergically strengthens the difference of collecting property between quartz and feldspar by collector,thus achieving the effect of efficient separation.A new strategy for flotation to separate quartz from feldspar in near-neutral pulp was provided. 展开更多
关键词 FELDSPAR QUARTZ Ca^(2+)-sodium silicate selective adsorption flotation separation
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Effectiveness of Sodium Silicate on the Corrosion Protection of AA7075-T6 Aluminium Alloy in Sodium Chloride Solution
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作者 Francesco Rosalbino Giorgio Scavino Graziano Ubertalli 《Materials Sciences and Applications》 2024年第4期53-65,共13页
The influence of sodium silicate on the corrosion behaviour of aluminium alloy 7075-T6 in 0.1 M sodium chloride solution was studied by open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) tec... The influence of sodium silicate on the corrosion behaviour of aluminium alloy 7075-T6 in 0.1 M sodium chloride solution was studied by open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) techniques. Scanning electron microscopy (SEM) was used to characterize the AA7075-T6 surface. Silicate can significantly reduce corrosion deterioration and the inhibition efficiency increases with the concentration of Na<sub>2</sub>SiO<sub>3</sub>. The corrosion inhibition mechanism involves the formation of a protective film over the alloy surface by adsorption of aluminosilicate anions from solution, as has also been suggested by others in literature. 展开更多
关键词 Aluminium Alloy 7075-T6 silicate Sodium Chloride Electrochemical Impedance Spectroscopy (EIS) Scanning Electron Microscopy (SEM)
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Reclamation of CO_(2) sodium silicate used sands by steam leaching 被引量:1
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作者 Ji-jun Lu Wei He +1 位作者 Lei Yang Hua-fang Wang 《China Foundry》 SCIE EI CAS CSCD 2023年第6期537-544,共8页
The bond film on the surface of the CO_(2) sodium silicate used sands is not easy to decompose,therefore,it is difficult to reclaim used sands.A new reclamation method of CO_(2) sodium silicate used sands was develope... The bond film on the surface of the CO_(2) sodium silicate used sands is not easy to decompose,therefore,it is difficult to reclaim used sands.A new reclamation method of CO_(2) sodium silicate used sands was developed by steam leaching,which can reduce the water consumption of reclamation and improve the removal effect of sodium silicate bond film.Firstly,the leaching effect of the sodium silicate sands after 20/200/400/600/800/1,000°C heat preservation treatment was simulated.Furthermore,the influence of the leaching time on the removal effect of the sodium silicate bond film was studied.Finally,the casting properties of the reclaimed sands after the leaching reclamation treatment were tested.The results show for simulated used sands after 30 min of steam leaching,the removal ratio of the alkali exceeds 84.1%,the removal ratio of silicate is 86.2%,and the removal ratio of carbonate is 93.6%.The removal rate of alkali,silicate and carbonate is relatively low in the leaching time of 30-50 min.Considering the reclamation effect and cost,the leaching time is controlled in 30 min.Water consumption is only 60%of the mass of used sands for 30 min steam leaching,while it is 200%for wet reclamation.Morphological analysis shows that most of the hazardous substances in the used sands are removed in 30 min steam leaching,and the reclaimed sands surface after steam leaching in 50 min is as smooth as new sands.After 30 min of steam leaching,the alkali removal effect of the factory used sands can reach 81.5%,the water consumption by the steam leaching reclamation is 58%of the mass of the used sand,which is similar to the result of simulated used sands.The performance of reclaimed sands obtained after 30 min steam leaching is better than that of new sands when the amount of sodium silicate added is 6%of the mass of the reclaimed sands and the CO_(2) blowing time is 15 s:the 24 h ultimate compressive strength of reclaimed sands is 5.6 MPa(equated with new sands),and the collapsibility compressive strength is 5.2 MPa,which is lower than the collapsibility compressive strength of new sands(7.7 MPa).This indicates that the reclamation of CO_(2) sodium silicate used sands by steam leaching is a feasible method. 展开更多
关键词 sodium silicate sands steam leaching simulated temperature RECLAMATION
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Structure, Formation, Properties, and Application of Calcium and Magnesium Silicate Hydrates System—A Review 被引量:1
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作者 肖建敏 LI Hui HU Yaru 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期604-615,共12页
In order to expand the advantages of strong durability and high compressive strength of calcium silicate hydrates(C-S-H),at the same time to make up for the poor early mechanical strength of magnesium silicate hydrate... In order to expand the advantages of strong durability and high compressive strength of calcium silicate hydrates(C-S-H),at the same time to make up for the poor early mechanical strength of magnesium silicate hydrates (M-S-H),we present the features and advantages of C-S-H and M-S-H and a comprehensive review of the progress on CaO-MgO-SiO_(2)-H_(2)O.Moreover,we systematically describe natural calcium and magnesium silicate minerals and thermodynamic properties of CaO-MgO-SiO_(2)-H_(2)O.The effect of magnesium on C-S-H and calcium on M-S-H is summarized deeply;the formation and structural feature of CaO-MgO-SiO_(2)-H_(2)O is also explained in detail.Finally,the development of calcium and magnesium silicate hydrates in the future is pointed out,and the further research is discussed and estimated. 展开更多
关键词 calcium and magnesium silicate hydrates thermodynamic properties STABILITY structural feature
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Selecting the Technology of Sodium Silicate Modified Poplar with the Highest Performance by Fuzzy Orthogonal Method 被引量:1
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作者 Xiaoqian Bi Pengfei Guan +3 位作者 Ping Li Yuan Zhang Xingong Li Yingfeng Zuo 《Journal of Renewable Materials》 SCIE EI 2023年第5期2399-2415,共17页
Sodium silicate modification can improve the overall performance of wood.The modification process has a great influence on the properties of modified wood.In this study,a new method was introduced to analyze the wood ... Sodium silicate modification can improve the overall performance of wood.The modification process has a great influence on the properties of modified wood.In this study,a new method was introduced to analyze the wood modification process,and the properties of modified wood were studied.Poplar wood was modified with sodium silicate by vacuum-pressure impregnation.After screening using single-factor experiments,an orthogonal experiment was carried out with solution concentration,impregnation time,impregnation pressure,and the cycle times as experimental factors.The modified poplar with the best properties was selected by fuzzy mathematics and characterized by SEM,FT-IR,XRD and TG.The results showed that some lignin and hemicellulose were removed from the wood due to the alkaline action of sodium silicate,and the orderly crystal area of poplar became disorderly,resulting in the reduction of crystallinity of the modified poplar wood.FT-IR analysis showed that sodium silicate was hydrolyzed to form polysilicic acid in wood,and structural analysis revealed the formation of Si-O-Si and Si-O-C,indicating that sodium silicate reacted with fibers on the wood cell wall.TG-DTG curves showed that the final residual mass of modified poplar wood increased from 25%to 67%,and the temperature of the maximum loss rate decreased from 343℃ to 276℃.The heat release and smoke release of modified poplar wood decreased obviously.This kind of material with high strength and fire resistance can be used in the outdoor building and indoor furniture. 展开更多
关键词 Poplar wood sodium silicate impregnation modification fuzzy orthogonal method process optimization flame retardant
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Influence of Na_(2)SiO_(3)/NaOH Ratio on Calcined Magnesium Silicate Based Geopolymer——Experimental and Predictive Study
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作者 Premkumar R Ramesh Babu Chokkalingam +1 位作者 Meyyappan PL Shanmugasundaram M 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第5期1077-1085,共9页
This study aims to investigate the behavior of alkali activated mortar,which is made of naturally available magnesium silicate as source material.For magnesium silicate,ultrafine natural steatite powder(UFNSP)is used ... This study aims to investigate the behavior of alkali activated mortar,which is made of naturally available magnesium silicate as source material.For magnesium silicate,ultrafine natural steatite powder(UFNSP)is used as the primary source of binder,and the activation is initiated through the alkali liquid which is proportioned in various combinations of silicate to hydroxide ratio(Na_(2)SiO_(3)/Na OH)ratio,and this ratio in this study varies from 1 to 3.The UFNSP is calcined at two difierent temperatures,700 and 1000℃.The mortar mix is proportioned as 1:3 between powder and the fine aggregate,and the mortar is prepared with hydroxide molarity(M)of 10 M.The mortar is cured for 48 hours at 60℃and the compressive strength was studied.All the mix were studied for its microstructural behavior along with compressive strength.The mix proportion of the mortar,and the results obtained through microstructural characterization were combinedly formed as input for artificial neural network(ANN)predictive modelling.The model is designed to predict the compressive strength,which is trained through Bayesian regularization algorithm with varying hidden neurons of 7 to 10.This experimental and predictive study shows that the strength is influenced by both Na_(2)SiO_(3)/Na OH ratio and calcination process.And the ANN is influenced by mainly calcination temperature and uncorrelation occurs in selected samples of 1000℃calcined UFNSP mix. 展开更多
关键词 magnesium silicate silicate alkali activation GEOPOLYMER UFNSP prediction
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Thermoluminescent response of gamma irradiated Na^(+)–Cu^(+) ionexchanged silicate glass in large dose range
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作者 Safa Toumi Khaled Farah 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第5期22-32,共11页
The introduction of metals into vitreous matrices is the origin of various interesting phenomena;in particular,the presence of copper ions in glass has been the subject of considerable research because of its numerous... The introduction of metals into vitreous matrices is the origin of various interesting phenomena;in particular,the presence of copper ions in glass has been the subject of considerable research because of its numerous applications.The ion-exchange process is primarily used to introduce copper ions into glass matrices.The thermoluminescence(TL)of silicate glass was studied to evaluate its potential as gamma-sensitive material for dosimetric applications;the effect of copper doping on the thermoluminescent sensitivity was investigated using the Cu-Na ion-exchange technique for different concentrations and doping conditions,over a wide dose range of 10 mGy to 100 kGy.The results showed that Cu doping significantly improved the sensitivity of the glasses to gamma radiation.After the ion-exchange,two peaks appeared in the glow curves at approximately 175 and 230°C,respectively,which possibly originated from the Cu^(+) centers,along with a weak TL peak at around 320℃.We also attempted to explain the origin of the observed thermoluminescence by exploiting the Electron paramagnetic resonance(EPR)spectra.The results clearly show quenching of the TL emission with increasing copper concentrations.The present work indicates that the thermoluminescence response of these glasses to gamma rays can be reasonably measured in the range of 0.001-100 kGy.This study also facilitates the understanding of the basic TL mechanism in this glass system. 展开更多
关键词 Cu-Na ion-exchange silicate glass THERMOLUMINESCENCE Gamma irradiation Electron paramagnetic resonance
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Improvement of Selected Morphological, Physiological, and Biochemical Parameters of Banana (Musa acuminata L.) Using Potassium Silicate under Drought Stress Condition Grown in vitro
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作者 Hosny Abdel Aziz Mohamed Sharaf +7 位作者 Magdy Omar Ahmed Abou El-Yazied Nada Ibrahim AlJwaizea Shaimaa Ismail Mohamed M.A.Omar Khadiga Alharbi Amr Elkelish Moataz Tawfik 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第4期1019-1036,共18页
Drought stress has become more common in recent years as a result of climate change impacts on the production of banana crops and other fruit trees.The growth and productivity of Musa spp are severely impacted by the ... Drought stress has become more common in recent years as a result of climate change impacts on the production of banana crops and other fruit trees.The growth and productivity of Musa spp are severely impacted by the gradual degradation of water resources and the erratic distribution pattern of annual precipitation amount.The aim of the work includes increased drought tolerance in light of water scarcity in the world as a result of the bananas’being gluttonous for water needs.This investigation was carried out from 2019 to 2020 to study the effect of potassium silicate on morphological growth and biochemical parameters of Musa acuminata L under drought stress by PEG.As a result,drought stress reduced the morphological characteristics such as shoots number,shoot length,roots number,and survival percentage and biochemical characteristics such as chlorophyll a,b,carotenoids,stomatal status,and RWC.While proline content increased in the leaf of M.acuminata L.Media complemented with K2SiO3(2 to 6 mM)either individually or in combination with PEG led to an improvement in all morphological and biochemical characteristics.The activities of CAT,POD,and PPO enzymes increased significantly compared to control.Furthermore,the lowest PPO,CAT,and POD activity were achieved.Additionally,K2SiO3 treatments under drought stress successfully enhanced the leaf stomatal behavior.Our results suggest that K2SiO3 can help to maintain plant integrity in the tested cultivar under drought stress. 展开更多
关键词 Musa acuminata L potassium silicate photosynthetic pigments STOMATA enzymatic activity
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Study on the Attack of Molten Silicates on Plasma-Sprayed Thermal Barrier Coatings
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作者 Roberto Fernando Martins Karl Friehe +3 位作者 Cecília Chaves Guedes e Silva Dolores Ribeiro Ricci Lazar Antônio Augusto Couto Carlos Roberto Camello Lima 《Journal of Minerals and Materials Characterization and Engineering》 2023年第5期115-130,共16页
Thermal barrier coating (TBC) revolutionized the industry by allowing higher operating temperatures for equipment, such as gas turbines in the aeronautical industry. However, at high temperatures, the TBC is exposed t... Thermal barrier coating (TBC) revolutionized the industry by allowing higher operating temperatures for equipment, such as gas turbines in the aeronautical industry. However, at high temperatures, the TBC is exposed to the attack of molten silicates, known as CMAS (Calcium-Magnesium-Alumino-Silicate), which are particles from the environment that infiltrate the TBC, causing delamination. In this study, samples coated with TBC by thermal spray and covered with CMAS were evaluated at temperatures of 1200˚C and 1250˚C. For each temperature, exposure times of 1 h and 5 h were used. Samples with longer exposure time had a considerable volume increase. The main contribution of this work was to demonstrate the non-wettability of the CMAS, even in the 5-h heat treatments, which prevented its infiltration in the deeper regions. The conditions to guarantee the formation of the silicate and its consequent wettability are also discussed. 展开更多
关键词 Thermal Barrier Coatings Molten silicates Thermal Spray
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Variation in concentration of dissolved silicate in the Eastern Philippine deep sea
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作者 Ruixue XIA Qiang XIE +3 位作者 Weiqiang WANG Hongzhou XU Xuekun SHANG Yeqiang SHU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1454-1463,共10页
Upper Circumpolar Deep Water(UCDW)and North Pacifi c Deep Water(NPDW)coexist in the upper deep layer(i.e.,with a 1.2-2.0-℃potential temperature range and a 2000-4100-dbar pressure range)of the Eastern Philippine Sea.... Upper Circumpolar Deep Water(UCDW)and North Pacifi c Deep Water(NPDW)coexist in the upper deep layer(i.e.,with a 1.2-2.0-℃potential temperature range and a 2000-4100-dbar pressure range)of the Eastern Philippine Sea.They have similar properties in potential temperature and salinity,while have a signifi cant diff erence in dissolved silicate.Based on the repeated observations along a 137°E transect from the World Ocean Database(WOD18),this study revealed the interannual variability of dissolved silicate in the upper deep layer of the Eastern Philippine Sea.Dissolved silicate increased in 1995,1996,2005,2006,and 2007,and decreased in 1997,2000,2001,2002,and 2004.Composition analysis showed that the large diff erence between positive and negative dissolved silicate anomalies occurred mainly at~15°N and north of 25°N,with the concentration reaching 4.25μmol/g.Further analysis indicated that the interannual dissolved silicate variability was related to the zonal current variation in the upper deep layer.The relatively strong(weak)westward current transport increased(decreased)NPDW to the Eastern Philippine Sea,thereby resulting in increased(decreased)dissolved silicate. 展开更多
关键词 interannual variability North Pacific deep water upper deep layer dissolved silicate zonal velocity variability
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Early Triassic Silicic Volcanics of South China:Petrogenesis and Constraints on the Geodynamic Evolution of the Paleo-Tethys Ocean Region
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作者 WANG Yabo LIU Lei +2 位作者 ZHAO Zengxia LIU Xijun HUANG Wenmin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期617-629,共13页
The only occurrence of Lower Triassic silicic volcanic rocks within the South China Block is in the Qinzhou Bay area of Guangxi Province.LA-ICP-MS zircon U-Pb dating reveals that volcanic rocks of the Beisi and Banba ... The only occurrence of Lower Triassic silicic volcanic rocks within the South China Block is in the Qinzhou Bay area of Guangxi Province.LA-ICP-MS zircon U-Pb dating reveals that volcanic rocks of the Beisi and Banba formations formed between 248.8±1.6 and 246.5±1.3 Ma,coeval with peraluminous granites of the Qinzhou Bay Granitic Complex.The studied rhyolites and dacites are characterized by high SiO_(2),K_(2)O,and Al_(2)O_(3),and low MgO,CaO,and P_(2)O_(5) contents and are classified as high-K calc-alkaline S-type rocks,with A/CNK=0.98-1.19.The volcanic rocks are depleted in high field strength elements,e.g.,Nb,Ta,Ti,and P,and enriched in large ion lithophile elements,e.g.,Rb,K,Sr,and Ba.Although the analyzed volcanic rocks have extremely enriched zircon Hf isotopic compositions(ε_(Hf)(t)=-29.1 to-6.9),source discrimination indicators and high calculated Ti-in-zircon temperatures(798-835℃)reveal that magma derived from enriched lithospheric mantle not only provided a heat source for anatectic melting of the metasedimentary protoliths but was also an endmember component of the S-type silicic magma.The studied early Triassic volcanics are inferred to have formed immediately before closure of the Paleo-Tethys Ocean in this region,as the associated subduction would have generated an extensional setting in which the mantle-derived upwelling and volcanic activity occurred. 展开更多
关键词 GEOCHEMISTRY silicic volcanic rocks mantle contribution Olenekian-Anisian Paleo-Tethys oceanic plate subduction
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Study on Multi-Scale Tensile Strength and Tensile Strain of Calcium Silicate Hydrate Layered Nanocomposites Under External Physical Field
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作者 Lei FAN Lele ZHANG 《Research and Application of Materials Science》 2023年第1期1-4,共4页
Calcium silicate hydrate(C-S-H)is the mainly strength source of cement-based materials,but there is little basic research.In this paper,molecular dynamics method is applied to analyze the multi-scale tensile strength ... Calcium silicate hydrate(C-S-H)is the mainly strength source of cement-based materials,but there is little basic research.In this paper,molecular dynamics method is applied to analyze the multi-scale tensile strength and tensile strain of C-S-H layered materials under the condition of external physical fields(temperature and strain rate).The results show that the tensile strength and strain of C-S-H model decrease with temperature raises.The temperature(from 1 K to 600 K)has obvious influence on the tensile strain and strength of C-S-H layered materials.In addition,at(0.00025 ps^(-1)-0.001 ps^(-1)),the tensile strain and strength of C-S-H layered materials are less sensitive to strain rate.The whole model is closer to a 3-dimensional deformation.However,at(0.001 ps^(-1)-0.005 ps^(-1)),the dynamic load effect begins to increase,and the work done by the load per unit time increased.The tensile strain and strength of C-S-H layered materials indicates intensified by the change of strain rate.The energies are randomly distributed in the system,not concentrated in a certain area. 展开更多
关键词 Hydrated calcium silicate External physical field Multiscale Mechanical properties Molecular dynamics
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Adsorption of sodium polyacrylate at interface of dicalcium silicate-sodium aluminate solution 被引量:5
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作者 于海燕 潘晓林 +3 位作者 丁婷婷 张武 刘涵 毕诗文 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第10期2323-2326,共4页
The adsorption isotherm of sodium polyacrylate on dicalcium silicate(2CaO-SiO2) in sodium aluminate solution at 80 ℃ was studied.The type of surface adsorption of sodium polyacrylate is saturated adsorption,and the... The adsorption isotherm of sodium polyacrylate on dicalcium silicate(2CaO-SiO2) in sodium aluminate solution at 80 ℃ was studied.The type of surface adsorption of sodium polyacrylate is saturated adsorption,and the adsorption behavior belongs to L-type,according with the monolayer adsorption model of Langmuir equation.The surface coverage of sodium polyacrylate is 1.06 mol/μm2.The relation curve between the surface pressure and the molecular area of adsorption film was obtained by Gibbs formula.The variation of interfacial energy caused by adsorption as well as the relationship between the relation curve and the type of adsorption was discussed. 展开更多
关键词 sodium aluminate solution sodium polyacrylate dicalcium silicate INTERFACE ADSORPTION
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Leaching kinetics of zinc silicate in ammonium chloride solution 被引量:4
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作者 杨声海 李浩 +3 位作者 孙彦伟 陈永明 唐朝波 何静 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第6期1688-1695,共8页
The leaching kinetics of zinc silicate in ammonium chloride solution was investigated. The effects of stirring speed (150?400 r/min), leaching temperature (95-108 ℃, particle size of zinc silicate (61-150 μm... The leaching kinetics of zinc silicate in ammonium chloride solution was investigated. The effects of stirring speed (150?400 r/min), leaching temperature (95-108 ℃, particle size of zinc silicate (61-150 μm) and the concentration of ammonium chloride (3.5-5.5 mol/L) on leaching rate of zinc were studied. The results show that decreasing the particle size of zinc silicate and increasing the leaching temperature and concentration of ammonium chloride can obviously enhance the leaching rate of zinc. Among the kinetic models of the porous solids tested, the grain model with porous diffusion control can well describe the zinc leaching kinetics. The apparent activation energy of the leaching reaction is 161.26 kJ/mol and the reaction order with respect to ammonium chloride is 3.5. 展开更多
关键词 zinc silicate ammonium chloride LEACHING KINETICS porous diffusion control
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Self-healing mechanism of composite coatings obtained by phosphating and silicate sol post-sealing 被引量:8
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作者 林碧兰 卢锦堂 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第8期2723-2728,共6页
Silicate sol post-treatment was applied to form a complete composite coating on the phosphated zinc layer. The chemical compositions of the coatings were investigated using XPS. The coated samples were firstly scratch... Silicate sol post-treatment was applied to form a complete composite coating on the phosphated zinc layer. The chemical compositions of the coatings were investigated using XPS. The coated samples were firstly scratched and then exposed to the neutral salt spray(NSS) chamber for different time. The microstructure and chemical compositions of the scratches were studied using SEM and EDS. And the non-scratched coated samples were compared. The self-healing mechanism of the composite coatings was discussed. The results show that during corrosion, the self-healing ions in composite coatings dissolve, diffuse and transfer to the scratches or the defects, and then recombine with Zn2+ to form insoluble compound, which deposits and covers the exposed zinc. The corrosion products on the scratches contain silicon, phosphorous, oxygen, chloride and zinc, and they are compact, fine, needle and flake, effectively inhibiting the corrosion formation and expansion of the exposed zinc layer. The composite coatings have good self-healing ability. 展开更多
关键词 corrosion SELF-HEALING phosphate coatings silicate zinc
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Influence of sodium silicate on manganese electrodeposition in sulfate solution 被引量:2
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作者 薛建荣 钟宏 +2 位作者 王帅 李昌新 武芳芳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第4期1126-1137,共12页
The influences of sodium silicate on manganese electrodeposition in sulfate solution were investigated. Manganese electrodeposition experiments indicate that a certain amount of sodium silicate can improve cathode cur... The influences of sodium silicate on manganese electrodeposition in sulfate solution were investigated. Manganese electrodeposition experiments indicate that a certain amount of sodium silicate can improve cathode current efficiency and initial pH 7.0?8.0 is the optimized pH for high cathode current efficiency. The analyses of scanning electron microscopy (SEM) and X-ray diffraction (XRD) indicate the compact morphology and nanocrystalline structure of electrodeposits. X-ray photoelectron spectrometry (XPS) analysis shows that the elements of Mn, Si and O exist in the deposit. The solution chemistry calculations of sulfate electrolyte and sodium silicate solution indicate that species of Mn2+, MnSO4, Mn(SO4)2?2 , Mn2+, MnSiO3, Mn(NH3)2+, SiO32?and HSiO3? are the main active species during the process of manganese electrodeposition. The reaction trend between Mn2+ and Si-containing ions is confirmed by the thermodynamic analysis. In addition, polarization curve tests confirm that sodium silicate can increase the overpotential of hydrogen evolution reaction, and then indirectly improve the cathode current efficiency. 展开更多
关键词 ELECTRODEPOSITION MANGANESE sodium silicate electrodeposit structure hydrogen evolution reaction
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