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Journal articles on the topic 'Alkali elements'

Author: Grafiati

Published: 4 June 2021

Last updated: 17 June 2025

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Philip, Jackson, Wuerz Roland, Hariskos Dimitrios, Lotter Erwin, Witte Wolfram, and Powalla Michael. "Effects of heavy alkali elements in Cu(In,Ga)Se2 solar cells with efficiencies up to 22.6%." Physica Status Solidi RRL 10, no. 8 (2016): 583–86. https://doi.org/10.1002/pssr.201600199.

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We report on the use and effect of the alkali elements rubidium and caesium in the place of sodium and potassium in the alkali post deposition treatment (PDT) as applied to Cu(In,Ga)Se2 (CIGS) solar cell absorbers. In order to study the effects of the different alkali elements, we have produced a large number of CIGS solar cells with high efficiencies resulting in a good experimental resolution to detect even small differences in performance. We examine the electrical device parameters of these fully functional devices and observe a positive trend in the I–V parameters when moving from devices without PDT to KF-, RbF-, and eventually to CsF-PDT. A diode analysis reveals an improved diode quality for cells treated with heavier alkalis. Furthermore, secondary ion mass spectrometry (SIMS) measurements reveal a competitive mechanism induced within the class of alkali elements in the CIGS absorber induced by the alkali post deposition treatment.

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Nusbaum, Robert L., and S. Kerry Gant. "Alkali Metasomatism and Fossil Geothermal Activity: Wah Wah Springs Tuff, Utah." Mountain Geologist 24, no. 1 (1987): 26–29. http://dx.doi.org/10.31582/rmag.mg.24.1.26.

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Variable degrees of widespread alkali metasomatism have been detected within Wah Wah Springs Tuff samples collected in southwestern Utah. Highly altered samples show (1) strong periodic enrichment trends for alkali metals (except Na) at the expense of alkaline earth elements (except Ba), and (2) complete to partial replacement of andesine phenocrysts by K-feldspar: Mildly altered samples show (1) similar but less extreme enrichments and depletions compared to highly altered samples, and (2) no megascopic evidence of alteration. Cs is the most sensitive of the elements enriched by the alteration, followed by Rb and K20. Greater tendency toward fixation of heavy alkalis at low temperatures accompanying the addition of K-feldspar and the reduction of andesine explains. relative alteration trends. The lack of prvximal mineralization and widespread nature of alkali metasomatism associated with minor pmpylitic alteration suggests fossil geothermal activity in this part of Utah.

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Stone, H. E. N. "Valency relations between alkali and alkali earth elements and elements of second and third long periods." Materials Science and Technology 3, no. 3 (1987): 171–75. http://dx.doi.org/10.1179/mst.1987.3.3.171.

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Magee Jr., C. W., and C. A. Norris. "Alkali element background reduction in laser ICP-MS." Geoscientific Instrumentation, Methods and Data Systems 4, no. 1 (2015): 75–80. http://dx.doi.org/10.5194/gi-4-75-2015.

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Abstract. Alkali backgrounds in laser ablation ICP-MS analyses can be enhanced by electron-induced ionisation of alkali contamination on the skimmer cone, reducing effective detection limits for these elements. Traditionally, this problem is addressed by isolating analyses of high-alkali materials onto a designated cone set, or by operating the ICP-MS in a "soft extraction" mode, which reduces the energy of electrons repelled into the potentially contaminated sampling cone by the extraction field. Here we present a novel approach, where we replace the traditional alkali glass tuning standards with synthetic low-alkali glass reference materials. Using this vitreous tuning solution, we find that this approach reduces the amount of alkali contamination produced, halving backgrounds for the heavy alkali elements without any change to analytical procedures. Using segregated cones is still the most effective method for reducing lithium backgrounds, but since the procedures are complimentary, both can easily be applied to the routine operations of an analytical lab.

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Magee, C. W., and C. A. Norris. "Alkali element background reduction in laser ICP-MS." Geoscientific Instrumentation, Methods and Data Systems Discussions 4, no. 2 (2014): 609–26. http://dx.doi.org/10.5194/gid-4-609-2014.

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Abstract. Alkali backgrounds in laser ablation ICP-MS analyses can be enhanced by electron-induced ionization of alkali contamination on the skimmer cone, reducing effective detection limits for these elements. Traditionally, this problem is addressed by isolating analyses of high alkali materials onto a designated cone set, or by operating the ICP-MS in a "soft extraction" mode, which reduces the energy of electrons repelled into the potentially contaminated sampling cone by the extraction field. Here we present a novel approach, where we replace the traditional alkali glass tuning standards with synthetic low-alkali glass reference materials. Using this vitreous tuning solution, we find that this approach reduces the amount of alkali contamination produced, halving backgrounds for the heavy alkali elements without any change to analytical procedures. Using segregated cones is still the most effective method for reducing lithium backgrounds, but since the procedures are complimentary both can easily be applied to the routine operations of an analytical lab.

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Shidling, P. D., G. S. Giri, D. J. van der Hoek та ін. "Thermalization of different alkali and alkali-earth elements at the TRIμP facility". Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 622, № 1 (2010): 11–16. http://dx.doi.org/10.1016/j.nima.2010.07.048.

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KIRAN KUMAR, P. V., and M. V. SURYANARAYANA. "Precision two-photon spectroscopy of alkali elements." Pramana 83, no. 2 (2014): 189–219. http://dx.doi.org/10.1007/s12043-014-0789-3.

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Nahara, Annisa Ridha, Erlinda Ningsih, Raden Darmawan, and Sri Rachmania Juliastuti. "Optimization of Sidoarjo Mud Akaline Fusion Process Using Taguchi Method." Diffusion Foundations and Materials Applications 37 (December 24, 2024): 61–68. https://doi.org/10.4028/p-phldd4.

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Sidoarjo mud contains 48.3% silica which is considered as the biggest impurity when compared to the content of rare earth metals which are 0.3% Eu and 0.02% Yb. The hydrothermal process is used to bind silica as a form of silica extraction activity in the Sidoarjo mud so that the Rare Earth Elements are purified further because their uses are urgently needed. This process compares the alkalis in the form of Na2CO3 and K2CO3 which are basic salts which will then be compared to the most optimum conditions of the two alkalis. Each alkali will be processed under operating conditions following the Taguchi method which aims to minimize research and optimize research results. Based on the research results, it was found that K2CO3 provided better silica recovery than Na2CO3 under operating conditions with a K2CO3 concentration of 2 M, 1 hour soaking time, 700°C melting temperature and 3 hours melting time, giving 95.24% silica recovery. In addition, by using the Taguchi method it can be analyzed that the main factors affecting the melting of the alkali are the melting time, the concentration of the alkali, the temperature of the melting, and the immersion time.

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Norouzzadeh, Payam, Jerzy S. Krasinski, Charles W. Myles, and Daryoosh Vashaee. "Type VIII Si based clathrates: prospects for a giant thermoelectric power factor." Physical Chemistry Chemical Physics 17, no. 14 (2015): 8850–59. http://dx.doi.org/10.1039/c5cp00729a.

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Lichtenberg, Andreas, Lidia Inderdühnen, Aida Lichtenberg, and Sanjay Mathur. "Heterobimetallic Uranium(V)-Alkali Metal Alkoxides: Expanding the Chemistry of f-Block Elements." Molecules 30, no. 11 (2025): 2361. https://doi.org/10.3390/molecules30112361.

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Heterobimetallic uranium(V) alkoxides incorporating monovalent alkali metal counterions display remarkable structural versatility, dictated by the steric demands of the alkoxide ligands and the ionic radius of the alkali metal. Compounds of the general formula [UM(OtBu)6] (UM-OtBu-type: M = Na, K, Rb, Cs) were obtained by: (i) reacting [U(OtBu)5(py)] with equimolar amounts of alkali metal silylamides in tert-butyl alcohol, and (ii) oxidative transformation of [UM2(OtBu)6] (M = Na, K, Rb, Cs) upon reaction with iodine. Trans-alcoholysis of uranium heterobimetallic tert-butoxides with sterically less demanding iso-propyl alcohol yields oligomeric or polymeric iso-propoxide derivatives of the general formula [UM(OiPr)6]n, where the nuclearity depends on the alkali metal (n = 2 for M = Li; n = ∞ for M = Na, K, Rb). The capacity of alkali metal ions to adopt flexible coordination geometries results in different structural types ranging from finite clusters to infinite chains, with [ULi(OiPr)6]2 (ULi-OiPr-1) found to be dimeric, whereas [UM(OiPr)6]∞ (UM-OiPr-2-type, M = Na, K) and [URb(OiPr)6]∞ (URb-OiPr-3) exhibit a polymeric architecture. These findings provide fresh insights into the structure-directing influence of alkali metals on actinide coordination chemistry and broaden the chemistry of actinide alkoxides. All compounds were unambiguously characterized in both solution and solid-state through NMR and IR spectroscopic studies, as well as single crystal X-ray diffraction analysis.

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Neupane, Birat. "Regression Analysis for Better Understanding of Group I Elements." International Journal of Research and Review 11, no. 11 (2024): 531–37. https://doi.org/10.52403/ijrr.20241153.

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The compatibility of mathematical prediction and their agreement with the experimental data goes long way back in the history of science – most notably Physics. One of the important branches of mathematics is statistics and regression analysis is the vital element in this realm. The precise analysis and organizing of varying data have been possible due to the statistical calculations such as regression analysis. Through the intricate calculations of raw data using statistics, it has been easier for scientists to discover patterns and logical connection within the diverse range of data and information. Purpose: One of the important factors to distinguish the unique character of an element is its ionization energy or the energy required to make the electrons free from its atomic orbit or shell. Here, in this research, I have used the concept of Bohr’s atomic theory to determine the ionization energy of Hydrogen using mathematical analysis. Similarly, I have gathered the experimentally verified ionization energy data of other Group I alkali metals, and then I have used those data to establish logical connection between the elements using the mathematical concept of regression analysis. At last, I have shown how the ionization energy of Hydrogen varies greatly from the data obtained from the line of regression; Also, I have used the experimentally found regression equation to predict the ionization energy of the new hypothetical alkali metals having atomic number 119: which is yet to be experimentally verified. The main aim of this research was to show the mathematical relationship of the alkali metals and their compatibility with each other based on statistical analysis. Similarly, another purpose was to hypothetically establish the same coherent relationship between the alkali metals and unverified hypothetical element 119 using the underlying concept of statistics and mathematics. Statistical Methods: The atomic model of the, Danish physicist, Niels Bohr is used as a base model to calculate the ionization energy of Hydrogen; however, due to the limitation of the Bohr’s concept, the same method cannot be used to calculate the ionization energy of multiple electron system atoms. For this reason, experimentally verified ionization energy of alkali metals is taken as a raw data for the computational calculation of the line of regression and their corresponding equations. Keywords: Bohr’s atomic model, Regression analysis, Group I alkali metals, ionization energy (ground state level energy), Rydberg Constant, Planck Constant.

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Tanaka, Kazuya, and Naoko Watanabe. "Size distribution of alkali elements in riverbed sediment and its relevance to fractionation of alkali elements during chemical weathering." Chemical Geology 411 (September 2015): 12–18. http://dx.doi.org/10.1016/j.chemgeo.2015.05.025.

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VENKATARAMANAN, NATARAJAN SATHIYAMOORTHY, HIROSHI MIZUSEKI, and YOSHIYUKI KAWAZOE. "HYDROGEN STORAGE ON NANOFULLERENE CAGES." Nano 04, no. 05 (2009): 253–63. http://dx.doi.org/10.1142/s1793292009001733.

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In this paper, we discuss and compare various nanocage materials proposed theoretically as storage medium for hydrogen. Doping of transition elements leads to clustering which reduces the gravimetric density of hydrogen, while doping of alkali and alkali-earth metals on the nanocage materials, such as carborides, boronitride, and boron cages, were stabilized by the charger transfer from the dopant to the nanocage. Further, the alkali or alkali-earth elements exist with a charge, which are found to be responsible for the higher uptake of hydrogen, through a dipole–dipole and change-induced dipole interaction. The binding energies of hydrogen on these systems were found to be in the range of 0.1 eV to 0.2 eV, which are ideal for the practical applications in a reversible system.

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Owsiak, Z., J. Zapała-Sławeta, and P. Czapik. "Diagnosis of concrete structures distress due to alkali-aggregate reaction." Bulletin of the Polish Academy of Sciences Technical Sciences 63, no. 1 (2015): 23–29. http://dx.doi.org/10.1515/bpasts-2015-0003.

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Abstract Damage and defects observed in concrete elements, such as a network of microcracks, popouts and eflorrescence can be caused by a variety of deleterious processes. The causes can include mechanical (overloading), physical (freeze-thaw cycle) or chemical exposure (sulphate corrosion, alkali-aggregate reaction). This paper analyses distress due to alkali-silica reaction, detected in selected concrete structures. The analysed concrete elements exhibited cracking, exudations and surface popouts. Identification of the presence of hydrated sodium-potassiumcalcium silicate gel can be considered the primary symptom suggestive of an alkali-silica reaction attack. Other damage-causing mechanisms can occur simultaneously.

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Berdibekov, A.T., V.M. Yurov, A.V. Dolya, and S.A. Guchenko. "PRIMARY CRACKS IN ATOMICALLY SMOOTH CRYSTALS OF ALKALINE ELEMENTS." Annali d'Italia 41 (March 27, 2023): 109–19. https://doi.org/10.5281/zenodo.7774494.

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An alkali metal crystal consists of a surface layer of size R(I), which we will call the σ1 phase, and a base material, which we will call the σ2 phase. Since the surface energy of the layer R(I) with σ1 is 2 times less than the surface energy of the bulk phase, the destruction of the metal starts from the surface layer. Moreover, for an alkali metal, destruction begins from the (111) face. For crystals with identical atoms, the share of space occupied by them in one cube is 68% for alkali metals. The rest (32%) is occupied by empty space. After relaxation, we will call this space the maximum field of primary cracks. For us, the most important thing is the fact that the length of this crack L is equal to the thickness of the surface layer of the alkali metal R(I). This crack length reflects the peculiarity that it is associated not only with the geometry of crystal lattices, but also with the physical properties of crystals. We have proposed a model for calculating the length of primary cracks that appear in metals due to the presence of a surface layer R(I). Griffiths considered the change in the energy of a body with a crack under loading and obtained an energy criterion for failure. Our calculation of the crack length L for lithium Li gave L = 2.6 nm. For lithium Li, the average crack length is L = 2.2 nm, which does not differ much from our formula. This is to talk about the validity of our model.

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Wu, Yu Feng, Rui Qing Li, Qi Jun Zhang, and Wei Wang. "Extraction of Rare Earth Elements from Waste Trichromatic Fluorescent Phosphors." Advanced Materials Research 788 (September 2013): 279–82. http://dx.doi.org/10.4028/www.scientific.net/amr.788.279.

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Two methods, direct acid leaching, alkali fusion and acid leaching, were adopted to deal with the Waste Trichromatic Fluorescent Phosphors (WTFPs). The research results showed that using the direct acid leaching method can only dissolved the Red phosphors. And yet, high-temperature alkali fusion could effectively destroy the Mg-Al spinel structure of the components of the Blue and the Green phosphors, and make REEs dissolved completely. The acid leaching efficiency of REEs could reach 100% when the weight ratio of NaOH with WTFPs is 6:1, and the calcination temperature is 900 °C and the reaction time is 4 hrs.

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Le, Hai Son, Xuan Dinh Luu, Dinh Viet Nguyen, Cong Trinh Bui, Vladimir A. Karelin, and Andrey A. Smorokov. "The decomposition possibility of vietnamese monazite concentrate by the pressure alkali method." Bulletin of the Tomsk Polytechnic University Geo Assets Engineering 336, no. 3 (2025): 208–21. https://doi.org/10.18799/24131830/2025/3/4949.

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The authors have studied the decomposition of monazite concentrate by alkali. They investigated the necessary decomposition conditions such as temperature, time, particle size and the ratio between alkali and monazite concentrate by mass (wt/wt). The decomposition is best performed at >140°C, within 8 hours, the required alkali and monazite concentrate ratio was 1,4/1, the ore particle size needs to be smaller than 48 mm. The decomposition efficiency was also only about 70%. If the desired recovery efficiency was higher than 90%, the alkali/concentrate ratio by mass needed to be at least 4/1, resulting in a large amount of residual alkali. To improve this process, the authors studied the decomposition of monazite concentrate by alkali under pressure. The monazite was taken from Ham Tan deposit. The effecting parameters such as temperature, time, ratio between NaOH/concentrate by mass and particle size of the concentrate were investigated. The results showed that, under the effect of pressure, decomposition occurs faster, more thoroughly and decomposition efficiency increases. The suitable temperature for concentrate decomposition was from 180 to 210°C, corresponding to a pressure of 4 to 7 at. The decomposition time was also reduced to 2 hours and the particle size of the concentrate was also larger to 55 mm with 70% alkali and ratio of alkali/concentrate was 1/1. The decomposition efficiency of rare earth elements reached 95%, while under the same conditions, U was 50% and Th was 77%. When the reaction time increased, the efficiency of rare earth elements decomposition did not change much, but the decomposition efficiency of radioactive elements tended to increase. For particle sizes >55 mm, the process efficiency decreased sharply, and changes in reaction conditions were needed to increase the decomposition efficiency.

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Libotean, Dan Alexandru, Alexandru Chira, and Ferdinánd-Zsongor Gobesz. "Textile-Reinforced Concrete Structural Elements." Műszaki Tudományos Közlemények 8, no. 1 (2018): 61–66. http://dx.doi.org/10.33894/mtk-2018.08.07.

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Abstract The textile reinforced concrete is a material with increased mechanical properties that can allow the production of lighter structural elements. The alkali-resistant textile reinforcement is not affected by corrosion. A structural facade panel and a light pole were modeled in order to study their behavior in the case of wind pressure. The developed numerical simulations were calibrated according to available data from the literature. These simulations revealed information potentially useful in the planning of further experimental tests.

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Jak, Evgueni, and Peter Hayes. "The Use of Thermodynamic Modeling to Examine Alkali Recirculation in the Iron Blast Furnace." High Temperature Materials and Processes 31, no. 4-5 (2012): 657–65. http://dx.doi.org/10.1515/htmp-2012-0103.

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AbstractIt is widely recognized that alkali metals, such as, potassium and sodium can cause operational problems in the iron blast furnace. These elements can influence properties, such as, the softening and melting of ores, formation of scaffolds, coke properties, and refractory life. It has been established that recirculation of these elements occurs within the furnace. In the lower furnace vaporization occurs in the high temperature hearth and bosch regions, and condensation occurs in the upper furnace below or in the cohesive zone. For these reasons the input of alkalis into the furnace is strictly controlled.Optimized thermodynamic databases describing slags in the system Al2O3-CaO-FeO-Fe2O3-Na2O-K2O-MgO-SiO2 have been developed and, combined with the computer software FactSage; these databases have been used to predict the possible behaviour of alkalis in the blast furnace and to examine the effects of changing process variables on reactor performance. To demonstrate this approach to process modeling the furnace is considered as a two-stage equilibrium reaction system and the results of initial analysis are reported.

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Watanabe, Yoko, Yasuo Kojima, Toshihiro Ona, et al. "HISTOCHEMICAL STUDY ON HETEROGENEITY OF LIGNIN IN EUCALYPTUS SPECIES II. THE DISTRIBUTION OF LIGNINS AND POLYPHENOLS IN THE WALLS OF VARIOUS CELL TYPES." IAWA Journal 25, no. 3 (2004): 283–95. http://dx.doi.org/10.1163/22941932-90000366.

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We examined the effects of polyphenols on the analysis of lignin by histochemical methods, namely, the Mäule color reaction coupled with microspectrophotometry and ultraviolet microspectrophotometry, in wood of Eucalyptus camaldulensis and E. globulus. Thin sections and wood meals were extracted with solutions of alkali at different concentrations. The amounts of alkali-soluble extractives increased with increasing concentrations of NaOH. By contrast, there was no clear correlation between amounts of Klason lignin and the concentration of NaOH. The visible-light absorption spectra of cell walls of all woody tissues from both species changed after alkali extraction. In particular, the spectra of cell walls of vessel elements changed considerably, even when only a dilute solution of alkali was used. Ultraviolet absorption spectra did not show clear changes after extraction with alkali. These results indicate that polyphenols in cell walls affect the results of histochemical analysis. Therefore, a preliminary extraction with alkali, namely, extraction with a 1% solution of NaOH, is needed to assess the precise distribution of lignins in the cell walls of Eucalyptus wood by histochemical methods. The cell walls of wood fibers of Eucalyptus camaldulensis contained both guaiacyl and syringyl units and those of vessel walls contained mostly guaiacyl units. However, the cell walls of wood fibers in Eucalyptus globulus contained mainly syringyl units, while those of vessel elements contained both guaiacyl and syringyl units. Syringyl-type polyphenols, which have spectra similar to those of syringyl-type lignins, were found in the cell walls of wood fibers and vessel elements and in cell corners among wood fibers in both species of Eucalyptus.

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Գույումջյան, Հ․Պ․, та Շ․Վ․ Խաչատրյան. "ՍԵՎԱՆԻ ՕՖԻՈԼԻՏԱՅԻՆ ԳՈՏՈՒ ԿԱՐԲՈՆԱՏԻՏՆԵՐՆ ՈՐՊԵՍ ՆՈՐ ՖՈՐՄԱՑԻՈՆ ՏԻՊ". Proceedings of the YSU C: Geological and Geographical Sciences 50, № 1 (239) (2016): 3–10. http://dx.doi.org/10.46991/pysu:c/2016.50.1.003.

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In the article genetical problems of carbonatites of the Sevan ophiolite zone are discussed. According to the authors, carbonatites are genetically related to hyperbasites and are a new formation type of mantle rocks, which absolutely differ from classic carbonatites of alkaline ultrabasite complexes. The issue of impossibility of the occurrence of alkali-ultramafites and alkali-carbonatites from depleted of alkali elements magma of the upper mantle has been discussed.

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Zhao, Dong Nan, Zheng Liang Xue, Wei Wang, Yi Shan Li, and Sheng Qiang Song. "Process Analysis of Pb and Zn during Producing Iron Nuggets by Iron Bearing Dust." Advanced Materials Research 402 (November 2011): 173–78. http://dx.doi.org/10.4028/www.scientific.net/amr.402.173.

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Using the secondary iron bearing dust as raw material, to make high basicity and coal mixed briquette, and then the briquettes are rapid self-reduced to produce iron nuggets at high temperature, at the same time of obtain more pure iron nuggets, the removal rate of alkali metal elements Pb is above 90%,Zn is about removed completely, so as to solve the problem of the damage of alkali metal elements, and this can make great contributions to the energy conservation and emission reduction, and environment protection.

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Anenburg, Michael, John A. Mavrogenes, Corinne Frigo, and Frances Wall. "Rare earth element mobility in and around carbonatites controlled by sodium, potassium, and silica." Science Advances 6, no. 41 (2020): eabb6570. http://dx.doi.org/10.1126/sciadv.abb6570.

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Carbonatites and associated rocks are the main source of rare earth elements (REEs), metals essential to modern technologies. REE mineralization occurs in hydrothermal assemblages within or near carbonatites, suggesting aqueous transport of REE. We conducted experiments from 1200°C and 1.5 GPa to 200°C and 0.2 GPa using light (La) and heavy (Dy) REE, crystallizing fluorapatite intergrown with calcite through dolomite to ankerite. All experiments contained solutions with anions previously thought to mobilize REE (chloride, fluoride, and carbonate), but REEs were extensively soluble only when alkalis were present. Dysprosium was more soluble than lanthanum when alkali complexed. Addition of silica either traps REE in early crystallizing apatite or negates solubility increases by immobilizing alkalis in silicates. Anionic species such as halogens and carbonates are not sufficient for REE mobility. Additional complexing with alkalis is required for substantial REE transport in and around carbonatites as a precursor for economic grade-mineralization.

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Toyoda, Shoichi, Kimihisa Ito, and Masanori Tokuda. "Extraction of Rare Earth Elements by Alkali Hydrothermal Process." Materials Science Forum 70-72 (January 1991): 221–34. http://dx.doi.org/10.4028/www.scientific.net/msf.70-72.221.

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Balakrishnan, S., V. Midhun Reddy, and R. Nagarajan. "Ultrasonic coal washing to leach alkali elements from coals." Ultrasonics Sonochemistry 27 (November 2015): 235–40. http://dx.doi.org/10.1016/j.ultsonch.2015.05.014.

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Bouabdallah, Fouzia, Mohamed Fouzi Habita, Noureddine Ferhoune, and Nadjette Rehamnia. "Damages caused by alkali reactive concrete in structural elements." International Journal of Sustainable Materials and Structural Systems 3, no. 1 (2017): 79. http://dx.doi.org/10.1504/ijsmss.2017.092259.

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Rehamnia, Nadjette, Mohamed Fouzi Habita, Fouzia Bouabdallah, and Noureddine Ferhoune. "Damages caused by alkali reactive concrete in structural elements." International Journal of Sustainable Materials and Structural Systems 3, no. 1 (2017): 79. http://dx.doi.org/10.1504/ijsmss.2017.10013397.

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Spišiak, Ján, Roberta Prokešová, Juraj Butek, and Viera Šimonová. "Neogene Alkali Basalts from Central Slovakia (Ostrá Lúka Lava Complex); Mineralogy and Geochemistry." Minerals 12, no. 2 (2022): 195. http://dx.doi.org/10.3390/min12020195.

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Ostrá Lúka basalts are a product of the final phase of Neogene volcanism in Central Slovakia. Their major and trace elements composition is alkaline, a feature confirmed by light rare earth elements (LREE) relative enrichment and some incompatible trace elements ratios. The basalts contain rare surrounded gabbro cumulates. Their peculiarity is a strong zonation of olivines and clinopyroxene. The significant zonation probably indicates a short stop of the melt at shallow depth. The Sr, Nd and Pb isotope compositions indicate an origin from a moderately depleted mantle source. The mineral and chemical composition of the basalts is similar to the Pannonian basin alkali basalts and the Western and Central Europe alkali basalts.

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Narendra Babu, K., and Ansom Sebastian. "On the Genesis of Indian Beryls." Journal Geological Society of India 51, no. 3 (1998): 323–30. http://dx.doi.org/10.17491/jgsi/1998/510306.

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Abstract Beryl samples collected from pegmatites of Bihar, Rajasthan, Andhra Pradesh and Kerala. Showed marked correlations between chemical constituents and physical parameters. The following are the major observations of this study: (i) Specific gravity and refractive index vary with alkali elements, (ii) unit cell dimensions vary with divalent metal ions and alkali elements, (iii) Be content correlates with refractive index, unit cell dimension c and also with Li content. Beryl samples are alkali-poor and form two distinct populations with alkali concentration of 0.594-0.863 wt% and 1.468-1.871 wt%. These two chemical types of beryls possibly tally with two generations, one of primary zones and the other of late phase cleavelandite. The data also showed that the analysed beryls from Indian pegmatites contain extremely low concentrations of rare alkalies. Correlation of Al with divalent metal ions; and Be with Li signifies that both octahedral and tetrahedral substitutions can take place in these beryls. In the structural formula the sum (Al3++Me2+), in all cases, showed close proximity to 2 justifying octahedral substitution.

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Awad, Hamdy A., Ibrahim Abu El-Leil, Aleksey V. Nastavkin, et al. "Statistical analysis on the radiological assessment and geochemical studies of granite rocks in the north of Um Taghir area, Eastern Desert, Egypt." Open Chemistry 20, no. 1 (2022): 254–66. http://dx.doi.org/10.1515/chem-2022-0131.

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Abstract Granite rocks are currently one of the foremost raw materials that can be used for various economic purposes such as ornamentation and building materials, because they do not possess radioactive concentrations and have good physical and mechanical properties. The granite rocks of north Um Taghir are connected to neoproterozoic rocks and integrated to the north Arabian-Nubian Shield (ANS), which lies in Northeast Africa. Inductively coupled plasma mass spectrometry (ICP-MS) and X-ray fluorescence analysis, concurrent to some statistical analysis, have been carried for major oxides and some trace elements to extract much fundamental information by following certain mathematical methods. The exposed granite rock units in north Um Taghir are classified into four rock units represented by tonalite, granodiorite, monzogranite, and alkali-feldspar granite which are cut by different types of dikes. The magma of tonalite and granodiorite is low-to-medium K calc-alkaline affinity, while the magma of monzogranite and alkali-feldspar granite is medium-to-high K calc-alkaline affinity, and of metaluminous to peraluminous nature. Granite rocks show a slightly depletion of fractionated patterns from light rare earth elements (LREEs) to heavy rare earth elements (HREEs) with slightly positive to negative Eu anomalies from tonalite to monzogranite and alkali-feldspar granites. The statistical criteria have been achieved to explore the significant differences of radiological hazard parameters among samples. It is obvious that there is no homogeneity among samples; furthermore, in Kruskal–Wallis test, Mann–Whitney test, and Pearson correlation coefficient, it can be noticed that there are significant differences between each pair of samples: tonalite, monzogranite; tonalite, alkali-feldspar granite; granodiorite, monzogranite; and granodiorite, alkali-feldspar granite. There is a strong direct relationship among granodiorite and both tonalite and alkali-feldspar granite, and among alkali-feldspar granite and tonalite and granodiorite. There is a strong inverse relationship among monzogranite and tonalite, granodiorite, and alkali-feldspar granite. As stated by all results, it can be mentioned that the granite rocks have a worthy result of mechanical and physical properties. So that they can be used for various economic purposes.

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Santosh, M. "Geochemistry of feldspars from the Ambalavayal Molybdenite Prospect, Kerala." Journal Geological Society of India 27, no. 2 (1986): 185–93. http://dx.doi.org/10.17491/jgsi/1986/270202.

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Abstract Major and trace element geochemistry of coexisting alkali feldspar and plagioclase pairs from granite and alkali feldspars from the associated pegmatites of the Ambalavayal molybdenite prospect in Wynad district, Kerala, are presented. The element levels in both the feldspars show an overall comparability with the values reported from elsewhere. The nature of distribution of elements between coexisting feldspars is generally consistent with their crystal chemical behaviour. X-ray studies of alkali feldspars show a triclinic symmetry with the triclinicity values ranging from 0.2955 for feldspar from the granite to 0.6742 for feldspar from the pegmatite. Mol per cent feldspar end members range from Or56.43Ab40.52An3.05in alkali feldspar of the granite to Or74.00Ab22.51An3.19 in alkali feldspar of the pegmatite. The crystallization temperature of the alkali feldspar-plagioclase pairs in the granite is estimated to be between 704-740°C and that of alkali feldspar in the pegmatite to be between 525-580°C.

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Song, Xiaoqian, Yuhang Su, Jingwen Zheng, Zhonghua Zhang, Zhengwei Liang, and Zhonghua Tang. "Study on the Effects of Salt Tolerance Type, Soil Salinity and Soil Characteristics on the Element Composition of Chenopodiaceae Halophytes." Plants 11, no. 10 (2022): 1288. http://dx.doi.org/10.3390/plants11101288.

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With the continuous increase in saline–alkali land, sustainable development of the global environment and ecology have been seriously affected. This study compared the absorption and accumulation patterns of 11 elements in different parts (roots, stems and leaves) of different leaf Na regulation strategies of the pioneer plant Chenopodiaceae in saline–alkali land and evaluated the effects of soil nutrient status and soil salinity on the distribution of plant elements. The results showed that the changes in the content of Ca, Mg and Na in plants are affected by the salt-tolerant type and on different parts. Soil salinity had no significant effect on element concentrations in different parts of plants. The Pearson correlation coefficient showed that the correlation between plants and soil elements was different, and different parts of plants had the characteristics of selective absorption of soil elements. The salt tolerance type and soil mineral element concentrations explained most of the variation observed in element concentrations in Chenopodiaceae plants; the soil salinity property played only a minor role. It was concluded that the genetic factors are the prerequisite in the composition pattern of leaf elements in Chenopodiaceae, and soil factors are the key to determining element accumulation. These conclusions provide an effective reference for evaluating plant breeding and its response to environmental change in saline–alkali arid areas in Hulunbuir grassland and other parts of the world.

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Che, Dong, Mianping Zheng, Yuanyi Zhao, et al. "High Degree of Differentiation and Enrichment of Li, Rb and Cs in Potassic-Ultrapotassic Volcanic Rocks: An Example from the Lhasa Block, Tibet." Minerals 13, no. 3 (2023): 342. http://dx.doi.org/10.3390/min13030342.

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Post-collisional potassic-ultrapotassic volcanic rocks are widely developed in the Lhasa block, Qinghai-Tibet region. In this paper, it was observed for the first time that dilute alkali elements–Li, Rb, and Cs–exhibit supernormal enrichment in the research data of numerous potassic-ultrapotassic volcanic rocks in the Lhasa block. At the same time, there are few studies on the genesis of enrichment. Currently, 568 sets of published volcanic rock data and 8 sets of measured data in the Lhasa block are sorted in detail, and the genesis of dilute alkali element enrichment is explained by means of geochemical research methods. It is believed that the high degree of magmatic fractionation of potassic-ultrapotassic volcanic rocks in the Lhasa block is the main reason for the abnormal enrichment of dilute alkali elements such as Li, Rb, and Cs. The abnormal enrichment area is mainly located in the central and western parts of the Lhasa block with an age range of 25–13 Ma. The discrimination range of Zr/Hf and Nb/Ta with a high degree of differentiation of potassic-ultrapotassic volcanic rocks in the Lhasa block is divided by analogy with the research results of highly fractionated granites, which provides a reference for the study of the supernormal enrichment of dilute alkali elements in potassic-ultrapotassic volcanic rocks in this area.

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Gumiński, Cezary. "Solubility and the periodic table of elements." Pure and Applied Chemistry 87, no. 5 (2015): 477–85. http://dx.doi.org/10.1515/pac-2014-0935.

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AbstractInteresting general tendencies of changes of solubilities of elements and groups of compounds may be observed when the corresponding solubility data are arrayed according to the increasing atomic number of the elements. Such trends are exemplified with the data of various systems (metallic and salt-water type) evaluated in several volumes of the IUPAC-NIST Solubility Data Series. The solubilities of elements in mercury as well as in liquid alkali metals, when ordered according their atomic numbers, change roughly in a corresponding way as the temperatures and energies of melting or boiling points of the elements. However, majority of transition metals dissolved in alkali metals are subject to some side reactions with nonmetallic impurities that may drastically elevate their concentration levels. The solubilities of intermetallic compounds in mercury depend primarily on the energies of formation of these intermetallics in the binary alloys and then on the dissolution energies of the component metals in mercury. It has been observed that the experimental solubilities of metal halates in water show quite well defined periodical changes. The arrayed solubility data of rare earth metal fluorides and chlorides in water display quite smooth changes with the increasing atomic numbers if the solutes are isomorphic. Some exceptions from the smooth changes for rare earth metal bromides and iodides are explained. These general observations are useful in evaluating and predicting solubilities in experimentally unknown systems.

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Scharfe, Sandra, and Thomas F. Fässler. "Polyhedral nine-atom clusters of tetrel elements and intermetalloid derivatives." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 368, no. 1915 (2010): 1265–84. http://dx.doi.org/10.1098/rsta.2009.0270.

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Homoatomic polyanions have the basic capability for a bottom-up synthesis of nanostructured materials. Therefore, the chemistry and the structures of polyhedral nine-atom clusters of tetrel elements [E 9 ] 4− is highlighted. The nine-atom Zintl ions are available in good quantities for E = Si–Pb as binary alkali metal (A) phases of the composition A 4 E 9 or A 12 E 17 . Dissolution or extraction of the neat solids with aprotic solvents and crystallization with alkali metal-sequestering molecules or crown ethers leads to a large variety of structures containing homoatomic clusters with up to 45 E atoms. Cluster growth occurs via oxidative coupling reactions. The clusters can further act as a donor ligand in transition metal complexes, which is a first step to the formation of bimetallic clusters. The structures and some nuclear magnetic resonance spectroscopic properties of these so-called intermetalloid clusters are reviewed, with special emphasis on tetrel clusters that are endohedrally filled with transition metal atoms.

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George, Lyci, and Surendra K. Saxena. "Structural stability of metal hydrides, alanates and borohydrides of alkali and alkali- earth elements: A review." International Journal of Hydrogen Energy 35, no. 11 (2010): 5454–70. http://dx.doi.org/10.1016/j.ijhydene.2010.03.078.

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Artamonova, I. V., L. A. Lesnova, S. M. Rusakova, and E. B. Godunov. "Evaluation of alkali metals salts solubility." Izvestiya MGTU MAMI 7, no. 1-3 (2013): 5–8. http://dx.doi.org/10.17816/2074-0530-67744.

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Calculation of alkali metals salts solubility is made using two approaches: thermodynamic (or power) and on values of charge and ionic radius sizes. The estimation of salts and oxyhydroxides solubility for elements of 1А subgroups of periodic table is given.

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Santosh, M. "Granite-Molybdenite System of Ambalavayal, Kerala: Part I. Geochemistry and Petrogenesis of the Granite." Journal Geological Society of India 32, no. 2 (1988): 83–105. http://dx.doi.org/10.17491/jgsi/1988/320204.

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Abstract The 595 Ma old granite pluton punctures Precambrian low-alumina trondhjemites and occurs spatially related to the Moyar and Calicut fault-lineament. Mineralogically, it is a quartz-alkali-feldspar granite. Molybdenite occurs as disseminated flakes in the granite and associated pegmatites and as flaky aggregates in quartz veins. K: Na : Ca relationship suggests an adamellitic composition, whereas SiO2 vs. Log10K2O/MgO proportions confirm its alkaline nature. In Harker variation diagrams, the oxide weight percentages show overall magmatic trends. Among trace elements, the notable features are low large ion lithophile element contents, moderate to high transition element levels and extremely high light rare earth element values. High SiO2, K2O and Na2O values, with low abundance of Ba, Rb and Sr and enrichment of Nb and Zr are typical features comparable to alkali granites elsewhere. The Rb, Nb and Y characteristics denote a within-plate affinity. Petrochemical features indicate derivation of the granite from an alkali-enriched partial melt through quartz and alkali feldspar fractionation. The extremely high K/Rb values imply a K-enriched, Rb-depleted deep crustal source. The enrichment of LREE and HFS elements indicate an active role of CO2-rich volatiles in the petrogenetic regime.

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Siddique, Salman, and Jeong Gook Jang. "Mechanical Properties, Microstructure, and Chloride Content of Alkali-Activated Fly Ash Paste Made with Sea Water." Materials 13, no. 6 (2020): 1467. http://dx.doi.org/10.3390/ma13061467.

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The aim of the present study is to investigate the potential of sea water as a feasible alternative to produce alkali-activated fly ash material. The alkali-activated fly ash binder was fabricated by employing conventional pure water, tap water, and sea water based alkali activating solution. The characteristics of alkali-activated materials were examined by employing compressive strength, mercury intrusion porosimetry, XRD, FT-IR, and 29Si NMR along with ion chromatography for chloride immobilization. The results provided new insights demonstrating that sea water can be effectively used to produce alkali activated fly ash material. The presence of chloride in sea water contributed to increase compressive strength, refine microstructure, and mineralogical characteristics. Furthermore, a higher degree of polymerization on the sea water-based sample was observed by FT-IR and 29Si NMR analysis. However, the higher amount of free chloride ion even after immobilization in sea water-based alkali-activated material, should be considered before application in reinforced structural elements.

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Marsich, Lucia, Loredana Moimas, Valter Sergo, and Chiara Schmid. "Raman spectroscopic study of bioactive silica-based glasses: The role of the alkali/alkali earth ratio on the Non-Bridging Oxygen/Bridging Oxygen (NBO/BO) ratio." Spectroscopy 23, no. 3-4 (2009): 227–32. http://dx.doi.org/10.1155/2009/418698.

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Raman spectra of bioactive glasses of the Na2O–K2O–MgO–CaO–B2O3–P2O5–SiO2to be used in bone reconstruction systems have been collected from samples with three different concentrations of alkali and alkali earth elements. Compositions were chosen with a constant total amount of modifiers and formers, with only minor changes among the formers. The ratio of Non-Bridging Oxygens to Bridging Oxygens (NBO/BO) has been obtained from the Raman spectra and reported as a function of the alkali/alkali earth ratio, showing a linear increase. Dissolution tests indicate also a linear dependence of the amount of Na+, K+and Ca++ions leached in water on the alkali/alkali earth ratio. Consequently a calibration plot correlating the NBO/BO ratio with the amount of Na+, K+and Ca++ions leached in water has been obtained, thus demonstrating the sensitivity of the method, given that the changes from one glass composition to the other are of the order of some points in percentage among the glass modifiers.

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Kobayashi, Sengo, Koji Murakami, Kiyomichi Nakai, and Makoto Hino. "Microstructures and Cohesiveness of Alkali- and Heat-Treated Films on a Ti-15Zr-4Nb-4Ta Alloy." Materials Science Forum 539-543 (March 2007): 3706–11. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.3706.

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Microstructures of alkali- and/or heat-treated films on a Ti-15Zr-4Nb-4Ta alloy were analyzed by means of scanning electron microscopy, thin film X-ray diffraction and Auger electron spectroscopy. The cohesiveness of films was also evaluated by scratch tests. The films were formed by immersion in 5M aqueous NaOH solution at 60 °C for 86.4 ks (alkali treatment) followed by heating at 400–600 °C for 3.6 ks. The film on alloy formed by alkali treatment exhibits the same strucutre as that formed on an alkali-treated titanium. Compositional gradient of alloying elements, Zr, Nb and Ta, is detected in the film. The cohesion of alkali-treated film is considerably increased by the heat treatment, and the maximum cohesion is obtained by heating at 600 °C. The increase in cohesion of alkali-treated film by heat treatment is due to both the diffusion of Zr into film and the formation of sodium titanate on substrate.

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Aryanto, Noor C. D., and E. Suparka. "THE PETROLOGY CHARACTERISTIC OF GRANITOID ROCK BASED ON GEOCHEMICAL ANALYSIS OF BAJAU CAPE COAST AND ITS SURROUNDING, WEST KALIMANTAN." BULLETIN OF THE MARINE GEOLOGY 28, no. 1 (2016): 13. http://dx.doi.org/10.32693/bomg.28.1.2013.51.

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The aim of this study is to identify of petrology characteristic based on geochemical analysis in order to know the granitoid rock type. Administratively, the study area is in the City and District of Singkawang, West Kalimantan Province, at coordinate 108Â°48'30â€ - 109Â°1'30â€ E and 0Â°40'30â€ - 0Â°54'30â€ N and, situated Â± 145 km to the north of Pontianak City. The outcrop of granitoid along Bajau Cape coast and its surrounding, had been analyzed petrographically and geochemically using AAS method. Based on analysis of five samples show that the ratio mole of Al2O3/(CaO+Na2O +K2O) > 1 ranged between 1.12 and 1.7, while the rest of three samples are moderately aluminous, with a ratio value between 0.5 and 1.0. The ratio between K2O and (K2O+Na2O+CaO) ranges 0.07 to 0.55 (moderate) that forms alkali feldspar normative ranges from 3.8 to 15.89 wt%. This ratio shows that granite alkali feldspar is classified to be calc-alkaline series. Petrographically, this rock is porfiritic texture, hollocrystalline, granular hypodiomorphic and biotite present as phenocryst, yellowish brown, euhedral, thin and platy. The content of oxides element (Na2O and MgO) tend to decrease, whereas of other oxides elements, namely Al2O3, TiO2, K2O, FeO and CaO increased, parallel with the raising of SiO2. Therefore, the Singkawang Granitoid can be grouped as alkali feldspar granite, syeno-granite and quartz monzonite.   Keywords: petrography, geochemstry, major elements, calc-alcaline affinity, granitoid type and Bajau Coast, West Kalimantan.    Penelitian ini bertujuan untuk mengidentifikasi karakteristik petrologi, berdasarkan analisa geokimia sehingga jenis batuan granitoidnya dikenali. Secara administratif, daerah penelitian termasuk ke dalam Kota dan Kabupaten Singkawang, Provinsi Kalimantan Barat, pada koordinat 108Â°48'30â€ - 109Â°1'30â€ BT and 0Â°40'30â€ - 0Â°54'30â€ LU dan terletak Â± 145 km, arah utara dari Kota Pontianak. Singkapan batuan granitoid sepanjang pantai Tanjung Bajau dan sekitarnya telah dianalisis secara petrografi dan geokimia dengan menggunakan AAS. Berdasarkan 5 contoh yang dianalisa menunjukan perbandingan mol Al2O3/(CaO+Na2O +K2O) > 1, yakni berkisar antara 1,12-1,7, sedangkan 3 contoh sisanya bersifat peraluminus sedang, dengan nilai ratio antara 0.5-1.0. Perbandingan antara K2O dan (K2O+Na2O+CaO) berkisar antara 0,07-0,55 (sedang) yang membentuk alkali normatif feldspar berkisar 3,84 â€“ 15,89% (berat). Perbandingan tersebut menunjukan batuan Granit alkali feldspar yang tergolong dalam seri batuan kalk-alkali. Secara petrografi, batuan tersebut menunjukkan tekstur porfiritik, holokristalin, hipidiomorfik granular dengan biotit hadir sebagai fenokris, coklat kekuningan, euhedral, pipih dan sedikit berlembar. Kandungan unsur oksida (Na2O dan MgO) cenderung mengalami penurunan, sedangkan unsur oksida lainnya, yaitu Al2O3, TiO2, K2O, FeO dan CaO mengalami kenaikan sejalan dengan makin bertambahnya SiO2. Maka dengan demikian Granitoid Singkawang dapat dikelompokan menjadi granit alkali feldspar, syenit-granit dan kuarsa-monsonit.   Kata kunci: Petrografi, geokimia, senyawa utama, afinitas kalk-alkalin, batuan granitoid dan Pantai Bajau, Kalimantan Barat.

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Watanabe, Yoko, Yuzou Sano, Takayuki Asada, and Ryo Funada. "Histochemical Study of the Chemical Composition of Vestured Pits in two Species of Eucalyptus." IAWA Journal 27, no. 1 (2006): 33–43. http://dx.doi.org/10.1163/22941932-90000135.

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We analyzed the chemical composition of vestures of vessel elements and wood fibres of Eucalyptus camaldulensis and Eucalyptus globulus by ultraviolet (UV) microscopy, transmission electron microscopy (TEM) after staining with potassium permanganate (KMnO4) or the PATAg reaction, and field-emission scanning electron microscopy (FE-SEM). Samples were treated with dilute solutions of NaOH at various concentrations. Before treatment with alkali, the vestures on the secondary walls of vessel elements and wood fibres were visible on UV micrographs taken at 280 nm and were strongly stained by KMnO4. Vestures were strongly stained by the PATAg reaction in samples that had been treated with 0.1% NaOH. However, treatment with higher concentrations of NaOH dissolved the vestures. FE-SEM observations showed that the process of dissolution of vestures during alkali extraction differed between the two species. It appears that vestures in Eucalyptus woods consist mainly of alkali-soluble polyphenols and polysaccharides. In addition, the chemical composition of vestures may differ between the two species of Eucalyptus that we examined.

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Zhang, Guishan, Ren Peng, Hongxin Qiu, et al. "Origin of Northeast Fujian Basalts and Limitations on the Heterogeneity of Mantle Sources for Cenozoic Alkaline Magmatism across SE China: Evidence from Zircon U-Pb Dating, Petrological, Whole-Rock Geochemical, and Isotopic Studies." Minerals 10, no. 9 (2020): 770. http://dx.doi.org/10.3390/min10090770.

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Cenozoic alkali basalts in Southeast (SE) China generally are genetically related to intracontinental rifting. Hence, they can be used to probe the nature of their underlying mantle sources and aid studies of the tectonic background in this region. This paper focuses on the Shanhoujian alkali basalts located in Bailing County, northeastern Fujian, SE China. We herein report their petrology, whole-rock major, and trace element geochemistry, and Sr-Nd isotopic composition and provide a new zircon U-Pb age for the basalts (~40 Ma, Eocene). These data help to constrain the petrogenesis of alkali basalts, their mantle source, and tectonic settings. The basalts are characterized by high Mg# (58.21–63.52) with Na2O/K2O > 1. MgO content is weakly correlated with CaO and Cr content but shows no correlation with Ni and Fe2O3 (total). Such features suggest that fractionation of clinopyroxene rather than olivine was important. In terms of trace elements, the alkali basalts display: (1) enrichment in La, Ce, Rb, Ba, Nb, and Ta and depletion in K, Pb, Zr, Hf, and Ti and (2) notable fractionation of light rare earth elements from heavy rare earth elements. Determined (87Sr/86Sr)i is in the range of 0.7041–0.7040 and εNd (t) is between +3.2 and +3.3. The Shanhoujian alkali basalts show a notable affinity to oceanic island basalts (OIBs) with little assimilation of crustal materials. They were derived from a pyroxenite and carbonated peridotite mantle source metasomatized by sediments carried by the subduction plate at different depths. The primary magmas of these basalts were derived from partial melting of this metasomatized mantle source during upwelling of the asthenospheric mantle as an intracontinental rift formed through extension in this part of SE China.

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Alum, Benedict Nnachi. "Saponification Process and Soap Chemistry." INOSR APPLIED SCIENCES 12, no. 2 (2024): 51–56. http://dx.doi.org/10.59298/inosras/2024/12.2.515600.

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Saponification is the process of converting fats or oils into glycerol and soap by reacting with alkalis such as potassium or sodium hydroxide. This process is crucial for understanding the chemical makeup of soap and its applications. This review article focuses on the product's historical and modern applications while providing a thorough understanding of the chemistry and saponification process. This article explains the process of saponification, which turns natural fats or oils into soap and glycerol by using an alkali like KOH or NaOH. We explain the steps involved in saponification, which include the hydrolysis of the ester link, the creation of soap molecules, and the impact of the fatty acid chain on the soap's properties. Glycerol, another economically useful byproduct, has multiple uses across many industries and a reputation for sustainability. We also assess the impact of several factors on the soaps, such as temperature, alkali content, mixing techniques, curing times, and additive usage. This paper reviews the valid literature in depth using a thorough historical, scientific, and industrial examination of soap manufacture, including saponification techniques and soap chemistry. Using the bibliometric approach, this review draws attention to the scientific and technological elements of soap manufacture, as well as its wide range of uses in the disciplines of pharmacy, hygiene, and cosmetics. Keywords: Saponification, Soap chemistry, Alkali, Fatty Acids, Glycerol.

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Chang, Chuangchuang, Xiaoping Zou, Jin Cheng, Tao Ling, Yujun Yao, and Dan Chen. "Applied Trace Alkali Metal Elements for Semiconductor Property Modulation of Perovskite Thin Films." Molecules 24, no. 22 (2019): 4039. http://dx.doi.org/10.3390/molecules24224039.

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With the rapid consumption of energy, clean solar energy has become a key study and development subject, especially the when new renewable energy perovskite solar cells (PSCs) are involved. The doping method is a common means to modulate the properties of perovskite film. The main work of this paper is to incorporate trace amounts of alkali metal elements into the perovskite layer and observe the effects on the properties of the perovskite device and the majority carrier type of the perovskite film. Comparative analysis was performed by doping with Na+, K+, and Rb+ or using undoped devices in the perovskite layer. The results show that the incorporation of alkali metal ions into the perovskite layer has an important effect on the majority carrier type of the perovskite film. The majority carrier type of the undoped perovskite layer is N-type, and the majority carrier type of the perovskite layer doped with the alkali metal element is P-type. The carrier concentration of perovskite films is increased by at least two orders of magnitude after doping. That is to say, we can control the majority of the carrier type of the perovskite layer by controlling the doping subjectively. This will provide strong support for the development of future homojunction perovskite solar cells. This is of great help to improve the performance of PSC devices.

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Bellham, Peter, Michael S. Hill, and Gabriele Kociok-Köhn. "Alkali metal-mediated dehydrocoupling of Me2NH·BH3." Dalton Transactions 44, no. 27 (2015): 12078–81. http://dx.doi.org/10.1039/c5dt00178a.

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Bis(trimethylsilyl)amide derivatives of the group 1 elements (Li, Na, K) are competent pre-catalysts for the dehydrocoupling of Me2NH·BH3via the formation of intermediates containing [H3BNMe2BH2Me2N]− anions.

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Kawakita, Yukinobu, Makoto Yao, and Hirohisa Endo. "Electronic and Atomic Structures of Liquid Tellurium Containing Alkali Elements." Journal of the Physical Society of Japan 66, no. 5 (1997): 1339–50. http://dx.doi.org/10.1143/jpsj.66.1339.

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Srivalli, H., L. Nirmal, and R. Nagarajan. "Effect of cavitation on removal of alkali elements from coal." Journal of Physics: Conference Series 656 (December 3, 2015): 012107. http://dx.doi.org/10.1088/1742-6596/656/1/012107.

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Matsukata, Masahiko, Eiichi Kikuchi, and Yoshiro Morita. "Migration of alkali and alkaline earth elements into carbon black." Fuel 71, no. 6 (1992): 705–7. http://dx.doi.org/10.1016/0016-2361(92)90176-o.

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