Journal articles: 'Basicity'

1

Zhu, Xiang, Hong Ming Wang, Gui Rong Li, and Yu Tao Zhao. "Calculation Model of Activity for Slag System of CaO-SiO₂-Fe₂O₃." Advanced Materials Research 535-537 (June 2012): 2503–6. http://dx.doi.org/10.4028/www.scientific.net/amr.535-537.2503.

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Based on the coexistence theory of slag structure, the activity model of CaO-SiO2-Fe2O3 ternary slag system was established. The effects of Fe2O3 content and basicity on the activities of CaO and 2CaO•SiO2 were investigated. The structure units of Fe2O3 in the molten slag were discussed. The results indicate the slag basicity has a significant influence on the activities of CaO and 2CaO•SiO2. The activity of CaO increases with increasing slag basicity, while the activity of 2CaO•SiO2 increases with the increasing of slag basicity when the basicity is less than 1.8, which reaches the maximum value when the basicity is 1.8. In another word, when the slag basicity exceeds 1.8, the activity of 2CaO•SiO2 decreases with the increasing of slag basicity. In addition, the activities of CaO and 2CaO•SiO2 can be decreased by Fe2O3. Moreover, when the slag basicity is higher than 2.0, the activity of 2CaO•SiO2 increases slightly with the increasing of Fe2O3 content. The main structure units of Fe2O3 in molten slag are closely related to the slag basicity.

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2

Yokokawa, Toshio, Takashi Maekawa, and Nozomu Uchida. "Optical basicity." Bulletin of the Japan Institute of Metals 25, no. 1 (1986): 3–7. http://dx.doi.org/10.2320/materia1962.25.3.

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ISAENKO, G. E., D. A. KOVALEV, G. A. NECHKIN, D. A. CHERNAVIN, and V. A. KOBELEV. "EFFECT OF BASICITY ON COMPLEX METALLURGICAL PROPERTIES OF SINTER." Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information 78, no. 2 (March 14, 2022): 121–28. http://dx.doi.org/10.32339/0135-5910-2022-2-121-128.

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Metallurgical properties of sinter have a significant influence on its basicity. The dependence of cold and hot strength, softening point, reducibility and other physical and chemical properties of sinter on basicity was established by studies of many domestic and foreign scientists. However, taking into account essential increase of iron content in concentrate during decrease in silica content as a result of modernization of production in JSC Stoilensky GOK, the estimation of basicity influence on complex properties of sinter produced with the silica usage is actual. The results of laboratory research at Novolipetsk Iron and Steel Works with the purpose of study of sinter basicity influence on sintering process indexes, strength and high-temperature properties, including filterability of smelting products through the coke baffle are presented. The sinters of different basicity were produced in the laboratory conditions by sintering based on concentrate of Stoilensky GOK with iron content 68,0 %. The basicity of the charge CaO/SiO2 was varied in the range of 1.2‒2.0 units in steps of 0.2 units. In the process of research we selected the optimum rate of solid fuel for each charge from the condition of maximum vertical speed of sintering and sintering strength of sinter. It was found that increasing the basicity of sintering material leads to increasing cold and hot strength, narrowing interval of plastic-viscous state. The maximum vertical sintering rate and maximum specific capacity are reached at basicity 1.6. At basicity of 1.4 the minimum strength of sinter was obtained. It was established, that the sinter reducibility sharply increases at basicity of 1.6 units. With increase in basicity the temperature softening-melting interval (TSMI) of sinter decreases, which characterizes the cohesion zone. The widest TSMI is in sinter with basicity of 1.2, the narrowest – with basicity of 2.0. With increasing basicity of sinter the characteristics of the melt flow through the coke packing increases. The mixture of 55% of sinter with 2.0 basicity and 45% of unfluxed pellets from Stoilensky GOK had the best flow characteristics of the melt products and slag.

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Zeng, Q., J. L. Li, G. J. Ma, and H. Y. Zhu. "Effect of binary basicity on chromium occurrence in stainless steel slag." Journal of Mining and Metallurgy, Section B: Metallurgy 58, no. 1 (2022): 11–18. http://dx.doi.org/10.2298/jmmb210304043z.

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Comprehensive utilization of stainless-steel slag (SSS) is restrained due to the risk of Cr6+ leaching. Based on the studying the microstructure of synthetic slag (SS) containing Cr2O3 with XRD, SEM-EDS, and Image pro, the effect of binary basicity on the chromium occurrence in SSS was investigated. The results indicated that the binary basicity had a significant impact on the properties of spinel crystals. There was a positive correlation between the calcium content in spinel crystals and the SS basicity. The size of spinel crystals varied from large to small and the precipitation occurrence changed with the basicity increase. Furthermore, the chromium occurrences changed with the basicity. The chromium was produced in spinel crystals at lower basicity, but as the basicity increased to 3.0, the chromium precipitated as calcium chromate. In view of the relationship between the chromium leaching behavior and its occurrence, increasing basicity raised the Cr6+ leaching.

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Zhang, Liheng, Zixian Gao, Songtao Yang, Weidong Tang, and Xiangxin Xue. "Effect of Basicity on Sintering Behavior and Metallurgical Properties of High-Chromium Vanadium-Titanium Magnetite." Metals 10, no. 5 (April 27, 2020): 569. http://dx.doi.org/10.3390/met10050569.

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Basicity has an important effect on the behavior of high-chromium vanadium-titanium magnetite (HCVTM) sinter. The effect of basicity on sintering, reduction, and softening-melting properties was investigated in an experiment-scale sinter pot. The results showed that with the basicity increasing from 1.7 to 2.5, the vertical sinter speed, the productivity, the particle size, the reduction disintegration index (RDI), and the reducibility index (RI) increased. The yield increased first and then decreased, while the tumble index (TI) had the opposite trend. The perovskite content increased first and then stabilized, and the silico-ferrite of calcium and aluminum (SFCA) increased from the basicity of 2.3. The HCVTM sinter had a better tendency of the softening behavior with the basicity increase. In addition, the melt droplet comprehensive index S increased, which indicated that the increase in basicity negatively affected the droplet performance. As the basicity increased, the comprehensive index value increased. Considering the adverse effect of basicity on softening-melting properties, the best recommended value is 2.3.

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Volceanov, Adrian. "Basicity or Ionicity – A New Approach for Understanding Glass Properties." Advanced Materials Research 39-40 (April 2008): 129–34. http://dx.doi.org/10.4028/www.scientific.net/amr.39-40.129.

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Basicity of glass is still a challenge in spite of various attempts to measure or calculate it. The values assigned for basicity of glasses, either calculated or experimentally determined, are not always in full agreement with actual facts, and discrepancies among the theoretical ones are not unusual. For instance, SiO2 is described by a single basicity value even if the polymorphs of SiO2 are quite different. Only few attempts were made to face this challenge. Present paper deals with a novel approach on theoretical ionicity / basicity based on electronic energy levels or band structure of solids. Another major adjustment takes into account the possibility of decomposing ionicity of complex chemical bondings into a sum of binary bondings. Considering the distribution of the interbonding angles specific for vitreous systems, it is possible to estimate both a local ionicity (basicity) of bondings and a global (mean) basicity of glass. The variation of basicity (ionicity) with temperature is also presented, this finding being able to open a new view on thermal history of glass considered through chemical character of bondings.

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7

Wang, Hong Ming, Xiang Zhu, and Gui Rong Li. "Calculation Model of Mass Action Concentration for CaO-B₂O₃-SiO₂ Slag System." Advanced Materials Research 634-638 (January 2013): 3114–17. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.3114.

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According to the coexistence theory of melted slag structure, a calculation model of mass action concentrations for CaO-B2O3-SiO2 slag system has been established, by which the mass action concentrations of all structure units in CaO-B2O3-SiO2 systems are calculated. The results indicate that the activities of CaO and 2CaO•SiO2 can be decreased effectively by B2O3. Furthermore, when the slag basicity is higher than 2.0, the activity of 2CaO•SiO2 increases firstly and then decreases with the increasing of B2O3 content. The activity of CaO increases with the increasing of slag basicity. When the basicity is less than 2.2, the activity of 2CaO•SiO2 increases with the increase of slag basicity. Moreover, when the basicity is 2.2, the activity of 2CaO•SiO2 reaches the maximum value. In another word, the activity of 2CaO•SiO2 decreases with the increase of slag basicity on the condition that the slag basicity exceeds 2.2. B2O3 exists in the slag in the form of CaO•B2O3, 2CaO•B2O3 and 3CaO•B2O3.

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Li, Jianli, Qiang Zeng, Qiqiang Mou, and Yue Yu. "Effect of Basicity on Precipitation of Spinel Crystals in a CaO-SiO2-MgO-Cr2O3-FeO System." High Temperature Materials and Processes 38, no. 2019 (February 25, 2019): 867–72. http://dx.doi.org/10.1515/htmp-2019-0043.

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AbstractThe comprehensive utilization of stainless steel slag is one of major problems to be solved at “green steelworks”. Precipitation of spinel crystals can effectively detoxify residue. The effect of basicity defined by ω(CaO)/ ω(SiO2) ratio on precipitation of spinel crystals in a CaO-SiO2-MgO-Cr2O3-8 wt% FeO system has been determined with such tools as FactSage 7.1, SEM-EDS, IPP 6.0 and XRD. The FactSage 7.1 results showed that the rate of spinel phase enrichment with chromium was about 98% for the system basicity less than 1.4 and about 78% above this value. The precipitation of solid particles in solution appeared to be significantly influenced by basicity. With its increase the solid phase grew, the liquid one reduced, the particle diffusion was limited, and the growth of spinel crystals was inhibited. The spinel crystal size increased rapidly with decrease of basicity. When basicity increased from 0.6 up to 1.0, the crystal size decreased sharply from 12.30 μm down to 6.22 μm, and the reduction constituted as much as 49.43%. When basicity increased from 1.0 up to 2.2, the spinel crystal size moderately decreased from 6.22 μm down to 4.47 μm. Therefore, reduction of basicity is conducive to spinel crystal enrichment with chromium what appears to be a key factor to control basicity at detoxification of the chromium-containing steel slag.

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9

Agbodan, Kokou Agbékonyi, Oudjaniyobi Simalou, Gneiny Whad Tchani, and Koffi Jondo. "Etude de l’influence de la basicité sur l’enthalpie de réaction des sels N-méthoxycarbonyl-(oxy)-pyridiniums." International Journal of Biological and Chemical Sciences 14, no. 4 (August 17, 2020): 1489–98. http://dx.doi.org/10.4314/ijbcs.v14i4.26.

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Les hétérocycles sont importants, aussi bien dans les domaines biologique, médicinal et thérapeutique (vitamines, hormones, antibiotiques, etc), que dans le secteur industriel et technologique (inhibiteurs de corrosion, colorants, agents stabilisants, pesticides, herbicides. Les chloroformiates ou chlorocarbonates sont les esters dérivés de l’acide chloroformique. La chimie des N-oxydes hétérocycliques (pyridine et N-oxydes) a connu un important développement au cours des dernières années. L’objectif principal du présent travail est l’étude de l’action du métoxycarbonylchloride sur la pyridine et certains de ses dérivés. Après avoir trouvé les conditions optimales, de nouveaux composés à base de pyridine ont été synthétisés. En remplaçant l’ion chlorure par d’autres ions, les produits synthétisés ont été cristallisés avec un bon rendement. La structure des produits a été caractérisée à l’aide de la spectroscopie infra rouge et la résonnance magnétique nucléaire. Spécifiquement, l’influence de la basicité du noyau hétérocyclique sur les enthalpies de formation des sels produits a été étudiée. En conclusion, la réaction chimique de formation est exothermique avec ΔH° < 0 pour tous les sels étudiés. En utilisant les constantes de Hammett sur le noyau de la pyridine, l’étude a monté que ces chaleurs de réaction dépendent de la basicité du noyau hétérocyclique. En perspective on peut envisager une étude de l’influence de la basicité des différents noyaux pyridiniques sur les effets de conjugaison polaire directe sur le groupe azoté dans les sels N-méthoxycarbonyl-(oxy)-pyridiniums.Mots clés: Pyridine N-Oxyde, chloroformiates, synthèse, constante de Hammett. English Title: Study of the influence of basicity on the enthalpy of reaction of N-methoxycarbonyl- (oxy) -pyridinium salts Heterocycles are important, as well in the biological, medicinal and therapeutic fields (vitamins, hormones, antibiotics, etc.), as in the industrial and technological sector (corrosion inhibitors, dyes, stabilizing agents, pesticides, herbicides). Chloroformates or chlorocarbonates are esters derived from chloroformic acid. The chemistry of heterocyclic N-oxides (pyridine and N-oxides) has experienced significant development in recent years. The main objective of this work is to study the action of metoxycarbonylchloride on pyridine and some of its derivatives. After finding the optimal conditions, new pyridine-based compounds were synthesized. By replacing the chloride ion with other ions, the synthesized products have been crystallized with good yield. Specifically, the influence of the basicity of the heterocyclic nucleus on the enthalpies of salt formation produced has been studied. The enthalpies formation of salt produced have been determined. In conclusion, the chemical reaction of formation is exothermic with ΔH ° < 0 for all the salts studied. Using Hammett's constants on the pyridine nucleus, the study has shown that these reaction heats depend on the basicity of the heterocyclic nucleus. In perspective, we can study the influence of the basicity of the different pyridine rings on the effects of direct polar conjugation on the nitrogen group in the N-methoxycarbonyl- (oxy) -pyridinium salts.Keywords: Pyridine N-Oxide, chloroformates, synthesis, Hammett constant.

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10

Strandkvist, Ida, Kjell Pålsson, Anton Andersson, Jenny Olofsson, Andreas Lennartsson, Caisa Samuelsson, and Fredrik Engström. "Minimizing Chromium Leaching from Low-Alloy Electric Arc Furnace (EAF) Slag by Adjusting the Basicity and Cooling Rate to Control Brownmillerite Formation." Applied Sciences 10, no. 1 (December 19, 2019): 35. http://dx.doi.org/10.3390/app10010035.

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Brownmillerite is connected to chromium leaching when present in steel slags. To prevent chromium leaching, brownmillerite in slag should be prevented. Two methods for decreasing brownmillerite content in low-alloy electric arc furnace (EAF) slag were investigated: decreasing the basicity and increasing the cooling rate. The methods were tried on both laboratory scale and in full-scale production. In the laboratory scale experiments, chromium leaching decreased as the basicity decreased until brownmillerite was no longer present, slower cooling resulted in increased chromium leaching, and faster cooling decreased chromium leaching. In full-scale production, basicity modified single batches, with a basicity below 2.2, generally leached less chromium than slag batches with higher basicity, thus verifying the correlation between basicity and chromium leaching seen in laboratory scale experiments. The cooling process in the full-scale experiments was achieved either by letting the slag cool by itself in the air or by water spraying. The water-sprayed slag, which cooled faster, had less chromium leaching than the air-cooled slag. The full-scale production experiments confirmed that both decreasing basicity below 2.2 and increasing the rate of cooling could be used to decrease chromium leaching.

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11

Ning, Zhe, Xiyu Wang, and Songtao Yang. "Influence of Vanadium–Titanium Sinter Basicity on Cohesive Dripping Properties of Blast Furnace Comprehensive Burden." Minerals 14, no. 3 (March 11, 2024): 293. http://dx.doi.org/10.3390/min14030293.

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Vanadium–titanium ore possesses significant mining and utilization value. The basicity of vanadium–titanium sinter has a direct impact on the formation, location, thickness, permeability, and heat exchange of the cohesive zone in the blast furnace. This paper investigated the influence of increasing the basicity of the sinter on the comprehensive burden’s cohesive dripping properties in the blast furnace, while keeping the final slag basicity constant. This study was conducted through cohesive dripping property experiments. The findings indicated that as the sinter basicity in the comprehensive burden structure increased and the corresponding increase in the proportion of pellets occurred, the softening performance of the comprehensive burden improved, the cohesive zone became thinner, the lower edge of the cohesive zone shifted upward, and the softening melting properties became better in general. With an increase in the sinter basicity, the dripping difference pressure of the comprehensive burden decreased, and the dripping rate firstly increased and then decreased. An increase in the sinter basicity of the comprehensive burden structure promoted V reduction, and the V element yield and Cr element yield of the sinter were both increased; the optimal sinter basicity was 2.5, and the corresponding pellet proportion was 42%.

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12

Ping, Wang, Wu Hao, Chun Tie-jun, Zhou Song, and Zhou Tian-bao. "Reduction swelling mechanism of hematite fluxed briquettes." High Temperature Materials and Processes 41, no. 1 (January 1, 2022): 172–80. http://dx.doi.org/10.1515/htmp-2022-0023.

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Abstract The reduction swelling behaviors of the fluxed briquettes with basicity (CaO/SiO2) in the range of 0.33–1.33 were determined by adding analytical-grade CaO. Results showed that with the increase of basicity, the diameter, volume, and porosity of briquettes increased gradually, whereas the diameter, volume, and porosity of briquettes decreased when the basicity was greater than 0.83. The volume and porosity of briquettes decreased gradually with the increase in firing temperature. The reduction swelling index (RSI) reached the maximum at the basicity of 0.83. The RSI of fluxed briquettes was fired at 1,230°C, and that at the basicity of 0.83 was 20.12% after 60 min of reduction. The RSI of the fluxed briquettes was 3.16% when the basicity of briquettes was 0 upon firing at 1,300°C. The reducibility and swelling were positively correlated with internal porosity. The higher the swelling of briquettes, the denser was the distribution of iron whiskers. The lower the swelling of briquettes, the more closely the iron particles connected.

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13

Shi, Benjing, Deqing Zhu, Jian Pan, and Zhaocai Wang. "Research on the Preparation of Sinter for COREX Reduction Process by Varying Basicity and MgO Content." Minerals 12, no. 2 (February 6, 2022): 207. http://dx.doi.org/10.3390/min12020207.

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Sinter has been introduced into the composite burden of the COREX ironmaking process in China to lower the material cost, but the proportion is limited due to its poor low-temperature reduction degradation performance in the shaft furnace. This work dealt with the preparation of sinter for the COREX process by varying the MgO content and basicity. Their effects on the sintering and reduction properties under reducing condition simulating COREX shaft furnace were investigated, and the changes in the mineralogy of sinter with different MgO content and basicity were explored. The results showed that increasing MgO content affected the sinter strength and solid fuel consumption but restrained reduction degradation of sinter in the shaft furnace. In the basicity range of 0.8–2.6, the strength, RDI+6.3 and RDI+3.15 of sinter all presented a V-shaped curve and the minimum value occurred at a basicity of approximately 1.6. By comprehensive consideration, sinter with 2.35%+ MgO and 2.2+ basicity for COREX process was proposed and verified in industrial tests. Sinter with higher MgO content contained less SFCA and hematite, while glass and SFCA were dominant in the binding phase in sinter with low basicity (0.8) and high basicity (2.6) respectively and were associated with the relatively higher sinter strength. The changes in the mineralogy of sinter determined the variations of RDI of sinter with different MgO content and basicity, by affecting the sinter strength and the probable reduction of inner stress.

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14

Turchaninov, V. K., and L. V. Baikalova. "Basicity of azoles." Russian Chemical Bulletin 43, no. 9 (September 1994): 1512–15. http://dx.doi.org/10.1007/bf00697138.

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Peters, Maike V, Ragnar S Stoll, Andreas Kühn, and Stefan Hecht. "Photoswitching of Basicity." Angewandte Chemie International Edition 47, no. 32 (July 28, 2008): 5968–72. http://dx.doi.org/10.1002/anie.200802050.

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16

Drenth, W., and A. Hogervorst. "Basicity of alkynylphosphines." Recueil des Travaux Chimiques des Pays-Bas 87, no. 1 (September 2, 2010): 41–44. http://dx.doi.org/10.1002/recl.19680870107.

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17

Chen, Lin Zhi, Robert Flammang, Andre Maquestiau, Robert W. Taft, Javier Catalan, Pilar Cabildo, Rosa M. Claramunt, and Jose Elguero. "Thermodynamic basicity vs. kinetic basicity of diazoles (imidazoles and pyrazoles)." Journal of Organic Chemistry 56, no. 1 (January 1991): 179–83. http://dx.doi.org/10.1021/jo00001a036.

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18

Honeyands, Tom, Thi Bang Tuyen Nguyen, David Pinson, Paul R. J. Connolly, Mark I. Pownceby, James Manuel, Leanne Matthews, John Leedham, Tejbir Singh, and Damien P. O’Dea. "Variation in Iron Ore Sinter Mineralogy with Changes in Basicity." Minerals 12, no. 10 (September 30, 2022): 1249. http://dx.doi.org/10.3390/min12101249.

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The target basicity of iron ore sinter is set by blast furnace slag composition requirements, and therefore varies with the proportion of acid burden such as lump iron ore and pellets. Increasing the lump proportion of the burden will increase the target sinter basicity. The mineralogy of sinter produced with a range of basicity between 1.0 and 3.0 was analysed using optical point counting under reflected light microscopy. Sinter from BlueScope Steel’s industrial sinter strand was analysed over a 30-year period, during which time a wide range of iron ore fines blends were utilised and several significant process modifications made. These data were compared with the mineralogy of sinters produced in a pilot-scale sinter pot, a laboratory-scale milli-pot, and small-scale sinter analogues. The mineralogy of the sinters from all scales followed a predictable trend with basicity, generally following the diagram proposed by Bagnall. At a basicity of 1.0, high temperatures were required to produce sinter with adequate strength, resulting in bonding phases dominated by magnetite and glass. Increasing basicity to 2.0 decreased the required sintering temperature and changed the mineralogy to a majority of hematite and SFCA. Further increases in basicity to 3.0 further decreased the required sintering temperature and increased the SFCA and dicalcium silicate content.

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Metelkin, A. A., O. Yu Sheshukov, M. V. Savel’ev, O. I. Shevchenko, and D. K. Egiazar’yan. "Application of ionic theory to calculate sulfide capacity of slags." Izvestiya. Ferrous Metallurgy 64, no. 2 (April 2, 2021): 104–11. http://dx.doi.org/10.17073/0368-0797-2021-2-104-111.

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The article considers the issues of sulfur removal in the ladle-furnace unit. The sulfur distribution coefficient depends on sulfide capacity of the slag, sulfur activity coefficient, oxidizing potential of the medium and equilibrium constant. The sulfide capacity CS of slags is one of the most important characteristics of refining capacity of the slags used in extra-furnace steel processing. One of the factors affecting the sulfide capacity is temperature. The formula was proposed showing the dependence of sulfide capacity on the optical basicity and temperature, in the temperature range of 1650 – 1400 °C and when the optical basicity Λ is not more than 0.75; the error of the presented formula does not exceed 6 %. The formula for calculating the optical basicity is proposed, which takes into account the influence of basic, acidic oxides and amphoteric oxide Al2O3. It is shown that slags, completely consisting of a homogeneous phase, have an increased optical basicity of aluminum oxide. Heterogeneous slags have a reduced optical basicity of Al2O3 in comparison with homogeneous slags. Perhaps, this fact can be explained by the fact that in homogeneous slags there is a deficiency of the basic oxide CaO and in the conditions under consideration Al2O3 compound begins to exhibit more basic properties than acidic ones, thus, in homogeneous slags, the optical basicity of aluminum oxide is increased and approaches optical basicity of CaO oxide. Calculations carried out on the basis of real heats have shown that with an increase in the content of Al2O3 oxide in the slag, its optical basicity decreases. Known value of the optical basicity makes it possible to determine sulfide capacity of the slag, sulfur distribution coefficient between metal and slag, and, accordingly, final sulfur content in the metal. The research results have shown that it is advisable to apply the ionic theory of slags for the sulfide capacity determination.

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Meilong, Hu, Wei Ruirui, Gao Leizhang, Liu Lu, and Bai Chenguang. "Effect of the Basicity on the Crystallization Behavior of Titanium Bearing Blast Furnace Slag." High Temperature Materials and Processes 37, no. 3 (March 26, 2018): 193–200. http://dx.doi.org/10.1515/htmp-2016-0058.

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AbstractBasicity of titanium bearing blast furnace (BF) slag is critical for its crystallization behavior. Thermodynamics calculation indicates that rutile is the main phase after crystallization (or at room temperature). It precipitates during the cooling when the basicity of the slag is lower than 0.7. With increasing basicity, perovskite appears and becomes the main phase instead which contains titanium. Crystallization temperature of perovskite is higher than that of rutile and the other phases. Namely, perovskite crystallizes firstly from the molten slag during decreasing temperature. XRD analysis shows that CaTi21O38 is the main phase with a basicity of 0.6. CaMg0.39Al0.87Ti0.48Si1.26O6, CaTiSiO5 and CaMgSi2O6 are the main crystallization phases with a basicity of 0.8. The difference between experimental and thermodynamics calculation is due to the complicate crystallization behavior of the multiple slag under super cooling rate. When the slag basicity increases to 1.1, the main precipitatied phase is perovskite, which agrees well with theory calculation. In addition, the crystal structure of the synthesized titanium bearing slag is basically similar regardless of the basicity.

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Jun, Jin Oh, Joongwon Lee, Ki Hyuk Kang, and In Kyu Song. "Synthesis of Dimethyl Carbonate from Ethylene Carbonate and Methanol Over Nano-Catalysts Supported on CeO2–MgO." Journal of Nanoscience and Nanotechnology 15, no. 10 (October 1, 2015): 8330–35. http://dx.doi.org/10.1166/jnn.2015.11248.

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A series of CeO2(X)–MgO(1−X) (X = 0, 0.25, 0.5, 0.75, and 1.0) nano-catalysts were prepared by a co-precipitation method for use in the synthesis of dimethyl carbonate from ethylene carbonate and methanol. Among the CeO2(X)–MgO(1−X) catalysts, CeO2(0.25)–MgO(0.75) nano-catalyst showed the best catalytic performance. Alkali and alkaline earth metal oxides (MO = Li2O, K2O, Cs2O, SrO, and BaO) were then supported on CeO2(0.25)–MgO(0.75) by an incipient wetness impregnation method with an aim of improving the catalytic performance of CeO2(0.25)–MgO(0.75). Basicity of the catalysts was determined by CO2-TPD experiments in order to elucidate the effect of basicity on the catalytic performance. The correlation between catalytic performance and basicity showed that basicity played an important role in the reaction. Yield for dimethyl carbonate increased with increasing basicity of the catalysts. Among the catalysts tested, Li2O/CeO2(0.25)–MgO(0.75) nano-catalyst with the largest basicity showed the best catalytic performance in the synthesis of dimethyl carbonate.

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Zhang, Shu Qing, Xiu Ling Lv, Li Hong Zhang, and Na Hui Zhang. "Application in the Experimental Data Analysis of the Slag Viscosity with Minitab Software." Advanced Materials Research 753-755 (August 2013): 1857–61. http://dx.doi.org/10.4028/www.scientific.net/amr.753-755.1857.

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The single factor variance of viscosity experimental data of blast furnace slag was calculated by Minitab software. The influence of slag basicity and chemical compositions on the slag viscosity was obtained. The results show that there have insignificant effects on the slag viscosity when the slag basicity is over than 1.02, MgO content is less than 11.95% or TiO2 content is less than 12.57%. While the slag basicity can be influenced significantly with the slag basicity less than 1.02, MgO content over than 13.95% and TiO2 content over 13.57%. The Al2O3 content of the slag should be less than 12.75%.

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Cohen, Peter A., and Louis A. Cohen. "Correlation of the effects of alkyl substituents on the basicities of indoles." Canadian Journal of Chemistry 70, no. 1 (January 1, 1992): 282–84. http://dx.doi.org/10.1139/v92-039.

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Alkyl groups at C-2 of indole increase basicity at the site of protonation, C-3, while alkyl groups at C-3 decrease basicity. These opposing effects can be incorporated, for both the isomeric mono- and 2,3-dialkylindoles, into a single linear free energy correlation, pKa = −10.05Σσ −3.94, in which [Formula: see text] and Ds is the double bond stabilization parameter at C-3. An analogous correlation for N-methylindoles, pKa = −8.64Σσ −2.80, reveals that the effect of N-alkylation on basicity is predictable but not additive. Keywords: alkylindoles, carbon basicity, free energy correlation, substituent effects, N-alkyl effect.

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Wang, Hong Ming, Gui Rong Li, Xiang Zhu, and Yu Tao Zhao. "Calculation Model of Mass Action Concentrations for CaO-Al₂O₃-SiO₂ Slag System." Applied Mechanics and Materials 217-219 (November 2012): 39–42. http://dx.doi.org/10.4028/www.scientific.net/amm.217-219.39.

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According to the coexistence theory of melted slag structure, a calculation model of mass action concentrations for CaO-Al2O3-SiO2 slag system has been established, by which the mass action concentrations of all structure units in CaO-SiO2-Al2O3 systems are calculated. The effects of Al2O3 content and slag basicity on the mass action concentrations are investigated. The results indicate that both basicity and the content of Al2O3 have remarkable effects on mass action concentrations of CaO, 2CaO•SiO2, CaO•SiO2, CaO•Al2O3 and 2CaO•SiO2•Al2O3, etc. Furthermore, the effects of Al2O3 content on mass action concentrations are relevant with slag basicity. The basicity has more influences on mass action concentrations of CaO, CaO•SiO2, 2CaO•SiO2 and 3CaO•SiO2, whereas the basicity has little effect on mass action concentrations of other structure units in CaO-SiO2-Al2O3 system.

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Chai, Yifan, Yingjie Fan, Xing Gao, Guoping Luo, Yici Wang, Shengli An, and Jinzhou Liu. "Effect of Basicity on the Reduction Swelling Performance of Pellets Prepared from Bayan Obo Iron Ore Concentrate Based on Microscopic Characterization." Crystals 12, no. 10 (October 2, 2022): 1399. http://dx.doi.org/10.3390/cryst12101399.

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The development of blast furnace smelting technology with a high proportion of pellets is an important means for improving the utilization rate of complex co-associated mineral resources. The effect of basicity on the reduction swelling performance of pellets prepared from Bayan Obo iron ore concentrate is characterized by the aspects of microscopic morphology, element distribution and weight-loss behavior. The results show that with the increase in basicity, the reduction swelling rate and the weight-loss rate of pellets follows the change rule by first increasing and then decreasing. With a basicity of 0.8, the pellets have the largest swelling rate (75.743%) and the largest weight-loss rate (24.77%). The reduction swelling rate is proportional to the porosity and inversely proportional to the amount-of-liquid phase. In the first stage of reduction, pellets with a basicity of 0.8 changed from tabular to granular, and there were a large number of cracks. In the third stage of reduction, pellets with a basicity of 0.8 had coarse iron whiskers. In the same reduction stage, the amount of K and Na elements in the pellets with a basicity of 0.8 entering the iron oxide lattice was much larger than that in the pellets with a different basicity. As the reduction progresses, the ability of alkali metals to enter the iron oxide gradually increases.

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26

Shen, Yingying, Junkai Chong, Ziniu Huang, Jianke Tian, Wenjuan Zhang, Xingchang Tang, Wanwu Ding, and Xueyan Du. "Viscosity and Structure of a CaO-SiO2-FeO-MgO System during a Modified Process from Nickel Slag by CaO." Materials 12, no. 16 (August 12, 2019): 2562. http://dx.doi.org/10.3390/ma12162562.

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There is a high iron content in nickel slag that mainly exists in the fayalite phase. Basic oxide can destroy the stable structure of fayalite which is beneficial to the treatment and comprehensive utilization of nickel slag. The research was based on the composition of the raw nickel slag, taking the CaO-SiO2-FeO-MgO system as the object and CaO as a modifier. The effect of basicity on the melting characteristics, viscosity and structure of the CaO-SiO2-FeO-MgO system was studied. The relationship between the viscosity and structure of the CaO-SiO2-FeO-MgO system was also explored. The results show as follows: (1) When the basicity is lower than 0.90, the primary phase of the slag system is olivine phase. When the basicity is greater than 0.90, the primary phase of the slag system transforms into monoxide. When the basicity is 0.90, olivine and monoxide precipitate together as the temperature continues to decrease. At the same time, the liquidus temperature, softening temperature, hemispherical temperature, and flow temperature all reach the lowest value. (2) With the increase of basicity, the critical viscosity temperature of the CaO-SiO2-FeO-MgO system decreases first and then increases. Critical viscosity temperature is the lowest at the basicity of 0.90, which is 1295 °C. (3) When the slag system is heterogeneous, the viscosity of the molten slag increases rapidly because of the quantity of solid phase precipitated from the CaO-SiO2-FeO-MgO system. (4) When the slag system is in a homogeneous liquid phase, the molar fraction of O0 decreases with the increase of basicity and the mole fraction of O−, and O2− increases continuously at the basicity of 0.38~1.50. The silicate network structure is gradually depolymerized into simple monomers, resulting in the degree of polymerization, and the viscosity, being reduced. The mole fraction of different kinds of oxygen atoms is converged to a constant value when the basicity is above 1.20.

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27

Zhi, Jian-Ming, Jie Li, Jia-Hao Wang, Tian-Yu Jiang, and Ze-Yi Hua. "Effect of Basicity on the Microstructure of Sinter and Its Application Based on Deep Learning." Computational Intelligence and Neuroscience 2021 (September 9, 2021): 1–14. http://dx.doi.org/10.1155/2021/1082834.

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The influence of the evolution rule of basicity (0.6∼2.4) on the mineral composition and microstructure of sinter is studied by using a polarizing microscope, and the comprehensive application analysis of the drum index, vertical sintering speed, and yield of sinter shows that, over the course of an increase in basicity (0.6∼1.0), the mineral structure changed from the original porphyritic-granular structure to a porphyritic structure. At the same time, there was no calcium ferrite phase in the bonding phase at a basicity of less than 1.0; therefore, the downward trend of the three indicators is obvious. When the basicity was further increased to approximately 1.6, the main structure of the mineral phase changed from a corrosion structure to an interweaving corrosion structure. Because of the existence of a porphyritic-granular structure, the structure of the mineral phase was extremely inhomogeneous and most complex near the basicity of 1.6; although a small amount of calcium ferrite displayed an acicular structure, the drum index appeared to show a very low value. With an increase in basicity to 2.0, the mineral phase structure was dominated by an interweaving corrosion structure with a uniform framework, and the content of calcium ferrite reached the highest value. Moreover, a clear acicular structure developed, and the drum index also increased to the highest value. At a basicity of more than 2.0, a mineral structure began to appear and the corrosion, porphyritic-granular structure, and the drum index also showed a slightly declining trend. Therefore, in the actual production process, basicity should be avoided as far as possible at around 1.0 and 1.6 and it should be controlled at around 2.0. At the same time, based on the mineral facies data set of this paper, the convolutional neural network is used to carry out a simple prediction model experiment on the basicity corresponding to the mineral facies photos, and the effect is quite good, which provides a new idea and method for the follow-up study of mineral facies.

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28

Raczyńska, Ewa D., Jean-François Gal, Pierre-Charles Maria, and Hamid Saeidian. "Push–Pull Effect on the Gas-Phase Basicity of Nitriles: Transmission of the Resonance Effects by Methylenecyclopropene and Cyclopropenimine π-Systems Substituted by Two Identically Strong Electron Donors." Symmetry 13, no. 9 (August 24, 2021): 1554. http://dx.doi.org/10.3390/sym13091554.

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The gas-phase basicity of nitriles can be enhanced by a push–pull effect. The role of the intercalated scaffold between the pushing group (electron-donor) and the pulling (electron-acceptor) nitrile group is crucial in the basicity enhancement, simultaneously having a transmission function and an intrinsic contribution to the basicity. In this study, we examine the methylenecyclopropene and the N-analog, cyclopropenimine, as the smallest cyclic π systems that can be considered for resonance propagation in a push–pull system, as well as their derivatives possessing two strong pushing groups (X) attached symmetrically to the cyclopropene scaffold. For basicity and push–pull effect investigations, we apply theoretical methods (DFT and G2). The effects of geometrical and rotational isomerism on the basicity are explored. We establish that the protonation of the cyano group is always favored. The push–pull effect of strong electron donor X substituents is very similar and the two π-systems appear to be good relays for this effect. The effects of groups in the two cyclopropene series are found to be proportional to the effects in the directly substituted nitrile series X–C≡N. In parallel to the basicity, changes in electron delocalization caused by protonation are also assessed on the basis of aromaticity indices. The calculated proton affinities of the nitrile series reported in this study enrich the gas-phase basicity scale of nitriles to around 1000 kJ mol−1.

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Bilalov, B. T., S. M. Farahani, and F. A. Guliyeva. "The Intuitionistic Fuzzy Normed Space of Coefficients." Abstract and Applied Analysis 2012 (2012): 1–11. http://dx.doi.org/10.1155/2012/969313.

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Intuitionistic fuzzy normed space is defined using concepts oft-norm andt-conorm. The concepts of fuzzy completeness, fuzzy minimality, fuzzy biorthogonality, fuzzy basicity, and fuzzy space of coefficients are introduced. Strong completeness of fuzzy space of coefficients with regard to fuzzy norm and strong basicity of canonical system in this space are proved. Strong basicity criterion in fuzzy Banach space is presented in terms of coefficient operator.

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30

Zhu, Xin Hua, Li Guang Zhu, Yu Liu, and Peng Fei Wang. "Effect of Basicity on Continuous Casting Mold Flux Properties." Advanced Materials Research 567 (September 2012): 62–65. http://dx.doi.org/10.4028/www.scientific.net/amr.567.62.

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Basicity is an important parameter which can determine the performance of continuous casting fluxes, and it have different effects on flux of various physical and chemical properties. This paper discusses the relationship and impact between basicity and the physical and chemical properties of flux, Which proved how changes of basicity affect physical and chemical properties of flux, and then how it affects the flux function .

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31

Yu, Huixiang, Xinhua Wang, Jing Zhang, and Wanjun Wang. "Laboratory Study on Oxide Inclusions in High-Strength Low-Alloyed Steel Refined by Slag with Basicity 2–5." High Temperature Materials and Processes 34, no. 7 (January 10, 2015): 675–82. http://dx.doi.org/10.1515/htmp-2014-0116.

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Abstract Non-metallic inclusions in high-strength low-alloyed steel refined by slag with basicity (B) 2–5 and Al2O3 content 20%–30% (in mass percent) were investigated by slag–metal equilibrium experiments in laboratory and thermodynamic calculations. Most inclusions in equilibrium were quasi-spherical CaO-MgO-Al2O3-SiO2 system and the sizes were less than 5 µm. The average content ratio, CaO/Al2O3 and CaO/SiO2 of the inclusions, increased with slag basicity increasing when Al2O3 content in slag was around 25%, MgO/Al2O3 and CaO/Al2O3 increased with Al2O3 content in slag decreasing when slag basicity was around 3.3. The MgO/Al2O3 of the inclusions was influenced mainly by Al2O3 content in slag and CaO/Al2O3 was influenced mainly by slag basicity. To make the inclusions out of relative lower melting region (<1,773 K), the values of CaO/Al2O3, MgO/Al2O3 and (CaO+MgO)/Al2O3 of the inclusions should be enhanced by increasing basicity and decreasing Al2O3 content in slag properly.

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32

Kruk, Mikalai M., Dmitry V. Klenitsky, Lev L. Gladkov, and Wouter Maes. "Corrole basicity in the excited states: Insights on structure–property relationships." Journal of Porphyrins and Phthalocyanines 24, no. 05n07 (May 2020): 765–74. http://dx.doi.org/10.1142/s1088424619501797.

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Steady-state fluorescence measurements and quantum-chemical DFT geometry optimizations are applied to extend the structure–property relationships between the free-base corrole macrocycle conformation and its basicity to the lowest excited S[Formula: see text] and T[Formula: see text] states. Direct basicity estimation in the lowest excited S[Formula: see text] state is demonstrated by means of fluorescence quantum yield measurements. The long wavelength T1 tautomer is found to retain its basicity in the S[Formula: see text] state, whereas the short wavelength T2 tautomer shows a noticeable decrease in basicity in the S[Formula: see text] state, which is related to the in-plane tilting of the pyrrole ring to be protonated. The conformational changes upon going from the ground to the lowest excited T[Formula: see text] state and the influence of the meso-aryl substitution pattern on the overall degree of distortions and tilting of the pyrrole ring to be protonated are also discussed from the point of view of macrocycle basicity.

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33

Laurence, Christian, Jérôme Graton, Michel Berthelot, and Mohamed J. El Ghomari. "The Diiodine Basicity Scale: Toward a General Halogen-Bond Basicity Scale." Chemistry - A European Journal 17, no. 37 (August 10, 2011): 10431–44. http://dx.doi.org/10.1002/chem.201101071.

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34

Buchori, Luqman, I. Istadi, P. Purwanto, Louis Claudia Marpaung, and Rahmatika Luthfiani Safitri. "Roles of K2O on the CaO-ZnO Catalyst and Its Influence on Catalyst Basicity for Biodiesel Production." E3S Web of Conferences 31 (2018): 02009. http://dx.doi.org/10.1051/e3sconf/20183102009.

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This research aimed to study the effect of K2O impregnation on the basicity of the CaO-ZnO catalyst and its effect on biodiesel production. The effect of mole ratio of CaO to ZnO catalyst and %wt K2O were also studied. The mole ratio of CaO to ZnO catalyst was varied at 1:1, 1:1.5, 1:2, 1:3, and 3:1, while the %wt K2O was varied at 1, 3, and 5 %. The catalyst basicity was determined by titration method. The basicity of the catalyst increased after the CaO-ZnO catalyst was impregnated with K2O in all mole ratios of CaO-ZnO catalyst. The addition of K2O as a promoter also increase the basicity. The highest basicity was obtained at the CaO-ZnO mole ratio of 3:1 and 5%wt K2O. The tranesterification process was carried out in a batch reactor at a methanol to oil mole ratio of 15:1, a reaction temperature of 60°C, a reaction time of 4 h, and a catalyst loading of 5%wt oil. The FAME yields obtained were 41.33%. These results proved that K2O plays a role in enhancing the catalyst basicity. In addition, K2O also serves as a binding agent to improve the mechanical properties of the catalyst.

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35

Ju, Jian-tao, Qi-di Li, Xiang-Dong xing, Xin-tai Jiang, Gui-qing Zhao, and Feng-lin Lu. "Effect of high basicity on compressive strength and microstructure of iron ore pellets containing TiO₂." Metallurgical Research & Technology 120, no. 3 (2023): 306. http://dx.doi.org/10.1051/metal/2023032.

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A laboratory study is carried out to characterize the effect of basicity (varying 1.5–3.5) on magnetite iron ore pellets containing TiO2 (content 5%). Green pellets are made by the laboratory scale balling disc and roasted at a horizontal tube furnace with 1220 °C. Thermogravimetric analysis (‘TG’) is used to analyze the thermal decomposition of green pellets. X-ray diffraction (‘XRD’), scanning electron microscope and energy dispersive spectroscopy (‘SEM-EDS’) are utilized to systematically analyze the phase composition, microstructure and elemental distribution of the pellets. The findings show that as the basicity increases the porosity increases first and then decreases while the compressive strength is opposite to porosity to decrease first and then increases. With the increases of basicity, CaO responded with Fe2O3 and TiO2 to form CaFe2O4, Ca2Fe2O5 and CaTiO3. ‘TG’ find basicity has a negative effect on pellet oxidation. Factsage7.1 software shows that with the increase of basicity, the liquid content increases. The ‘SEM-EDS’ result present that CaTiO3 is formed around hematite, impeding the hematite connection, increasing porosity and reducing compressive strength. Being depend on the experimental results, a schematic of the oxidation mechanism is presented, providing the theoretical foundations for the study of high basicity pellets.

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36

Cheng, Gongjin, Xuezhi Liu, He Yang, Xiangxin Xue, and Lanjie Li. "Sintering and Smelting Property Investigations of Ludwigite." Processes 10, no. 1 (January 13, 2022): 159. http://dx.doi.org/10.3390/pr10010159.

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In this paper, orthogonal experiments are designed to study the sintering and smelting characteristics of the ludwigite ore. The predominant influencing factors of the optimal ratio, basicity and carbon content on different single sintering indexes, including the vertical sintering speed, yield rate, drum strength and low-temperature reduction pulverization index, are firstly explored by the range analysis method, and the main influencing factors on comprehensive indexes are obtained by a weighted scoring method based on different single index investigation. Considering the sintering characteristics, the primary and secondary influencing factors are: ordinary ore ratio, carbon content and basicity, and the optimal ore blending scheme is: basicity 1.7, ordinary ore blending ratio 60% and carbon content 5%. In terms of the smelting characteristics, the research obtains the order of the influencing factors on the softening start temperature, softening end temperature, softening zone, smelting start temperature, dripping temperature, smelting-dripping zone, maximum pressure difference and gas permeability index of the ludwigite sinters by simply considering various single smelting indexes. On this basis, considering the comprehensive softening-melting-dripping characteristics, the primary and secondary influencing factors are: carbon content, ordinary ore ratio and basicity, and the optimal ore blending scheme is: basicity 1.9, ordinary ore blending ratio 60% and a carbon content of 5.5%. Comprehensively, considering the sintering and smelting property of the ludwigite ore, the primary and secondary influencing factors are: carbon content, ordinary ore ratio and basicity, and the optimal ore blending scheme is: basicity 1.9, ordinary ore blending ratio 60% and a carbon content of 5.5%.

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Diao, Jiang, Zhaoqun Ke, Lu Jiang, Zhen Zhang, Tao Zhang, and Bing Xie. "Structural Properties of Molten CaO–SiO2–P2O5–FeO System." High Temperature Materials and Processes 36, no. 9 (September 26, 2017): 871–76. http://dx.doi.org/10.1515/htmp-2016-0054.

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AbstractThe structural properties of molten CaO–SiO2–P2O5–FeO slag system with varying slag basicity have been investigated by molecular dynamic (MD) simulations using the pairwise potential model. The result shows that more than 95 % Si and 98 % P are four coordinated and form tetrahedral structures. Non-bridging oxygen occupies a predominant position in the system. With basicity increasing from 0.6 to 1.5, the proportion of non-bridging oxygen increases from 66.3 % to 77.3 %, whilst the bridging oxygen decreases from 30.1 % to 10.2 %. Both the result of MD simulations and Raman spectroscopic analysis show the proportion of Q0 increases with increasing slag basicity, whilst Q2 and Q3 decrease. The degree of polymerization of CaO–SiO2–P2O5–FeO system decreases with increasing slag basicity.

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38

Song, Hanlin, Jinpeng Zhang, and Xiangxin Xue. "Kinetics on Chromium-Bearing Vanadia-Titania Magnetite Smelting with High-Basicity Pellet." Processes 9, no. 5 (May 6, 2021): 811. http://dx.doi.org/10.3390/pr9050811.

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The effects of high-basicity pellet on smelting chromium-bearing vanadia-titania magnetite are investigated via thermodynamic smelting and non-isothermal kinetics experiments. The thermodynamic results indicated that the high-basicity pellet significantly affects and ameliorates the softening-melting-dripping behaviors during the smelting process. As the high-basicity pellet ratio increased from 0 wt.% to 52 wt.%, the range of softening temperature [T40–T4] decreased from 121 °C to 84 °C and the melting-dripping temperature [Td–Ts] decreased from 224 °C to 169 °C. Moreover, the apparent activation energy of non-isothermal kinetics also decreased from 99.91 kJ·mol−1 to 66.74 kJ·mol−1. Additionally, the reaction mechanism of high-basicity pellet on smelting chromium-bearing vanadia-titania magnetite was investigated via thermodynamic calculations of Gibbs free energy and characterizations of the titanium slag. Therefore, combined with the lowest permeability index, the fastest non-isothermal reduction rate, the highest recovery of valuable elements and the minimum content of titanium carbonitride, the preferable high-basicity pellet ratio was considered to be 11~23 wt.%.

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39

Yang, Wenkui, Jian Yang, Runhao Zhang, Han Sun, and Yunlong Qiu. "Effect of the Basicity on Mineralogical Phases and Micro-Structure of Dephosphorization Slag in the New Double Slag Converter Steelmaking Process." Metals 11, no. 9 (September 17, 2021): 1480. http://dx.doi.org/10.3390/met11091480.

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In the present work, the effect of the basicity at the lower range from 0.98 to 2.13 on dephosphorization of hot metal at 1623 K was studied through high-temperature laboratorial experiments. With the increase of the basicity from 0.98 to 2.13, the P and C contents in hot metal rapidly decrease and increase at first, and then gradually decrease and increase, respectively. From the scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray diffraction (XRD) results, with the increase of the basicity, the phase containing the high P content changes from the matrix phase into the phosphorus (P)-rich phase. Under the present experimental conditions, the P-rich phase can only be precipitated from the liquid slag when the basicity is higher than 1.55, which is a benefit to the dephosphorization. As the Raman intensity of the P-O-Ca structure unit in the P-rich phase is significantly higher than that of the P-O-Si structure unit, most of the phosphorus in the P-rich phase exists in the P-O-Ca structure unit and a small amount of phosphorus exists in the P-O-Si structure unit. With the increase of the basicity of the dephosphorization slag, the activity coefficient of P2O5, γ(P2O5) , in the liquid phase decreases, while the basicity in the liquid phase increases.

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40

Park, Sun-Young, Taeg Gyum Kim, Manjaly J. Ajitha, Kijeong Kwac, Young Min Lee, Heesu Kim, Yousung Jung, and Oh-Hoon Kwon. "The critical size of hydrogen-bonded alcohol clusters as effective Brønsted bases in solutions." Physical Chemistry Chemical Physics 18, no. 36 (2016): 24880–89. http://dx.doi.org/10.1039/c6cp01650b.

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Hydrogen-bonded clustering of alcohol molecules increases their basicity (proton affinity) significantly, so that alcohol dimers can accept a proton which otherwise is impossible due to insufficient basicity as a monomer.

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41

Zhang, Jin Zhu, and Jun Huang. "Influence of Flux on Sintering Property of Imported Hematite Ore." Advanced Materials Research 322 (August 2011): 139–43. http://dx.doi.org/10.4028/www.scientific.net/amr.322.139.

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The microstructure and compressive strength were investigated by means of optical microscopy, X-ray diffraction, and tensile testing machine. The influence of basicity, SiO2 and Al2O3 content on sintering property of hematite ore was studied. The results show that when the silica content was either 5.3% or 5.6%, the best result of the compressive strength of samples obtained at middle basicity. While the silica content was up to 5.9%, the greatest value of the compressive strength of samples attained at lower basicity.

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Isaenko, G. E., V. N. Titov, E. A. Andreeva, V. A. Kobelev, A. G. Nechkin, and D. A. Chernavin. "Estimation of hot metal desulfurization by intermediate and final blast-furnace slag when using pellets of different basicity in blast-furnace charge." Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information 79, no. 7 (August 21, 2023): 559–65. http://dx.doi.org/10.32339/0135-5910-2023-7-559-565.

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n the process of blast-furnace smelting, up to 90% of coke sulfur is captured by the iron ore charge, accumulating in hot metal in the amount that was absorbed from the gas phase. Desulphurization of cast iron occurs when it interacts first with the intermediate, and at the final stage, with the final blast-furnace slag. In this regard, it is of interest to evaluate the desulfurizing properties of the intermediate and final slag, which affect the sulfur content in hot metal. Melting mixtures of pellets of different basicity and sinter in a blast furnace leads to the formation of primary and intermediate slags of different chemical composition. When smelting hot metal in blast furnaces, mainly unfluxed pel-lets and fluxed sinter are used. In the course of the study, mixtures of sinter and pellets of different basicity were pre-pared, which ensured the production of final blast-furnace slag with a basicity of CaO/SiO2 = 1.15 units. The mixtures were reduced and melted in graphite crucibles with the smelting products filtered through a coke nozzle. The coeffi-cients of sulfur distribution between intermediate slag and hot metal obtained from iron ore charge with different basicity of sinter and pellets were determined. The lowest sulfur distribution coefficient between the intermediate slag and hot metal is observed when the basicity of the pellets is in the range of 0.5‒1.2 units. To increase the desulfurization capacity of the intermediate slag, it is advisable to use unfluxed and fluxed pellets with a basicity of 0.25 units in the blast-furnace charge and an sinter with a basicity of 1.78‒1.87 units. Studies of the kinetics of the interaction of hot metal and final blast-furnace slag have shown that the final slag provides a high degree of desulfurization of hot metal during their interaction for 1 hour or more

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Lian, Shuang Shii, You Yu Lin, Gu Ling Zhang, and Mu Rong Lu. "A Fast Method for Determining Physical Properties of Slags with Contact Angle." Advanced Materials Research 306-307 (August 2011): 467–70. http://dx.doi.org/10.4028/www.scientific.net/amr.306-307.467.

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In order to have good dephosphorization, it is beneficial to know the proper physical properties, including the melting point and viscosity of slag with fixed lime activity for steel refining, slag foaming and reaction in steel making. A fast way to determine the melting point and viscosity of complex multi-component slags is needed to control the quality of steel. In this study, experimental slag of FetO-CaO-SiO2-MgO-MnO-Al2O3 is obtained with electro slag remelting technique. The liquidus temperature of slag is determined with a video-based contact angle meter recorded with a high-speed camera and verified with an isopleth phase diagram of slag constructed with thermodynamic software FACTSAGE. The viscosity of liquid slag can be estimated with the optical basicity and liquidus temperature obtained from the calculated isopleth phase diagram, then it was compared with the experimental value measured by the rotating torque viscometer. The results indicated that substantial error between the calculated temperature of isopleth phase diagram and the value determined with method of contact angle in high basicity slag. On the other hand, minor difference exists between calculated liquidus temperature and measured temperature in low basicity slag. The viscosity estimated from the optical basicity and liquidus temperature of isopleth phase diagram show the similar behavior. It has good correlation between the calculated value and experimental value in low basicity, however, deviations are found in the range of high basicity.

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Long, Xiao, Wenbo Luo, Xiang Li, Shaolei Long, Honggang Ma, Dayang Luo, and Congxin Zheng. "Structure and Heat Transfer Characteristic Evolution of CaO-SiO2-CaF2-Based Solid Mold Flux Film upon Solidification." Metals 14, no. 1 (December 19, 2023): 1. http://dx.doi.org/10.3390/met14010001.

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In this study, two typical commercially used CaO-SiO2-CaF2-based mold fluxes with different basicities were adopted. Solid slag films of the two mold fluxes were obtained by immersing an improved water-cooled copper probe in the molten fluxes for different probe immersion times and molten slag temperatures. The film thickness, closed porosity, and roughness of the film surfaces in contact with the copper probe were measured. The heat flux through the solidified films and the comprehensive thermal conductivity of the films were both calculated. The results indicated that compared with the heat flux through high-basicity films, the heat flux through low-basicity films exhibited high fluctuation due to the evolution of fusion cracks within the glass layer. High-basicity mold fluxes resulted in higher thickness, growth velocity, surface roughness, and devitrification velocity of the films. With the growth and crystallization of the slag films, the comprehensive thermal conductivity of the high-basicity films increased significantly. For the low-basicity films, their comprehensive thermal conductivity first decreased and then increased after the solidification time exceeded 30 s. The comprehensive thermal conductivity of the high- and low-basicity films ranged from 0.63 to 0.91 and 0.62 to 0.81 W/(m·K), respectively. The results provide a novel method for analyzing the potential effect of the structural factors of slag films on heat transfer control and controlling the heat transfer behavior of slag films.

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Korzhenevskaya, N. G., V. I. Rybachenko, V. V. Kovalenko, S. N. Lyashchuk, and A. N. Red’ko. "Phenylhydrazines. Structure and basicity." Russian Journal of Organic Chemistry 43, no. 10 (October 2007): 1475–80. http://dx.doi.org/10.1134/s1070428007100119.

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Brauman, John I., and Chau Chung Han. "Carbon and proton basicity." Journal of the American Chemical Society 110, no. 17 (August 1988): 5611–13. http://dx.doi.org/10.1021/ja00225a002.

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Voronkov, M. G., V. V. Belyaeva, and K. A. Abzaeva. "Basicity of silatranes (Review)." Chemistry of Heterocyclic Compounds 47, no. 11 (February 2012): 1330–38. http://dx.doi.org/10.1007/s10593-012-0918-1.

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Morini, Marcela A., Rossana M. Minardi, Pablo C. Schulz, Jorge E. Puig, and María E. Hernández-Vargas. "Basicity of dodecyltrimethylammonium hydroxide." Colloids and Surfaces A: Physicochemical and Engineering Aspects 103, no. 1-2 (October 1995): 37–40. http://dx.doi.org/10.1016/0927-7757(95)03148-7.

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Shi, Xiaofang, Yu Wang, Bingjie Wang, and Lizhong Chang. "Effect of Basicity and Al2O3 Content in Slag on Cleanliness of Electroslag Ingot." Metals 13, no. 4 (March 23, 2023): 642. http://dx.doi.org/10.3390/met13040642.

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In order to clarify the mechanism for the increase in oxygen content during electroslag remelting, this paper analyzes in detail the effect of slag components on the gas content and number, size and composition of inclusions in electroslag ingots. The results show that, when the CaF2-MgF2-CaO-MgO-SiO2 slag system is used for electroslag remelting, the oxygen content in electroslag ingots decreases clearly with the increase in slag basicity. When the basicity is 14~3.3, the oxygen content in electroslag ingots is only 9~11 ppm. When the basicity drops to 2.3, the oxygen content increases to 20 ppm. The slag with high basicity also leads to a decrease in the number and size of inclusions with high Ca content. When the CaF2-MgF2-CaO-MgO-SiO2-Al2O3 slag system is used for electroslag remelting, with the increase in the Al2O3 content in slag with the same basicity, the oxygen content and inclusions in electroslag ingots gradually increase. However, the Al content in inclusions increases and the Ca content decreases. The decomposition of SiO2 and Al2O3 in slag is the main reason for the decrease in the cleanliness of electroslag ingots.

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Dumitrescu, Ovidiu, and Dorel Radu. "Basicity-Gibbs Free Energy Relationships for Binary Alkali Silicates." Advanced Materials Research 39-40 (April 2008): 169–72. http://dx.doi.org/10.4028/www.scientific.net/amr.39-40.169.

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In present paper there are presented such correlations for the silica-alkali systems (M2O – SiO2) where reliable thermodynamic data exists from the thermal equilibrium diagrams. It was observed that with the saturation of SiO2 tetrahedron with metal ions, the difference in basicity between the reactants is diminished, in the order SiO2 → disilicate → metasilicate → orthosilicate, and that confirms the role of driving force for these reactions of the acid-base interaction between oxides and the intermediate silicates formed. Also, there were proposed some correlations between the standard formation Gibbs free energy, (Gº298), and basicity percentage, pB, for the binary compounds from the same oxide systems. Considering the fact that for a system at equilibrium, reaction constant Kp depends on the reaction free Gibbs energy (rG0 298) and temperature, a correlation between basicity difference through basicity percentage, pB, and rG0 298 is proposed.

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Journal articles on the topic 'Basicity'

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