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Iron nanoparticles has attracted more attention than other nanomaterials for its small particle size, high magnetism, low toxicity, surface properties and its extensive applications in science. Plant extracts, microorganisms and agricultural waste products are used for the green synthesis of these nanoparticles. Green synthesis uses metabolites obtained from plants and microorganisms as reducing and covering agents. In addition, it provides an advantage over other synthesis methods because it does not contain harsh chemicals, uses non-toxic reagents, is biocompatible and environmentally friendly. In this study, iron-iron oxide (Fe-Fe3O4) nanoparticles (LP- Fe NPs) were synthesized using lemon peel extract and optimum Fe:Lemon peel extract (Fe: LP exract) ratio was determined. Nanoparticles were characterized by X-ray diffractometer (XRD), UV-vis Spectrophotometer and Scanning Electron Microscope (SEM). The UV-vis absorption spectrum of iron nanoparticles showed a peak in the 250-350 nm range. XRD analysis results confirmed that the product is a Fe-Fe3O4 mixture. According to SEM analysis results, the largest particle size according to the 1:2 ratio was recorded as 159 nm. The smallest particle size was recorded as 66.68 nm. It has been observed that the increased lemon peel extract causes agglomeration. As a result, green synthesis of lemon peel, which is agricultural waste; It creates low-cost, environmentally friendly products.

In modern era, people are spending their time indoors around 90%. Therefore, in terms of public health, increasing indoor air quality is of great importance. In this study, it was aimed to develop pearlescent pigments that emit negative air ions in order to increase indoor air quality, and the potential of such pigments for use in composite wall paint was evaluated. For this purpose, low refractive index muscovite mica and sericite clay minerals, which were shown to emit negative ions, were combined with high refractive index TiO2. The use of two different clay minerals, different proportions of SnO2 dopant, and calcination process application were selected as experimental parameters and the effect of these parameters on the anatase-rutile phase transformation of TiO2 in the pigments was investigated. Increasing the rutile TiO2 ratio in the synthesized pigments were resulted in a better pearlescent effect and lower photocatalytic activity. In order to increase the negative air ion emitting effect of these pigments with the desired pearlescent pigment properties, these samples were also combined with extract of the Chlorophytum comosum, which also is known to emit negative air ions. As a result of the negative ion emission measurements, it was found that the samples were continued to emit negative ions without a time-dependent decrease even when not combined with the extract of C. comosum. In addition, it was showed that the prepared samples have antibacterial effect against Escherichia coli, which is abundant in indoor environments, especially in health centers such as hospitals and dispensaries, and antifungal effect against Aspergillus niger, which is known as black mold, growing on moist walls.

Potassium borate was hydrothermally synthesized from various boron minerals (H3BO3, B2O3, Na2B4O7·5H2O and Na2B4O7·10H2O) at reaction conditions of 60–90 °C and 15–120 min. The synthesized potassium borate was identified as “santite (KB5O8·4H2O)” from the X-ray diffraction (XRD) analyses results. The specific band values between B and O atoms were characterized by Fourier transform infrared and Raman spectroscopies. Multiangular particles were generally observed in the range of 3.41 μm–234.94 nm. The use of different boron sources affected the morphology. Higher reaction yields were determined in the use of boric acid (H3BO3). Optical absorption of potassium borate minerals was approximately 340 nm. AC and DC electrical properties of materials were determined by using current–voltage and capacitance voltage characteristics. Electrical resistivity values of DC were found in the range of 4.17 × 108–4.07 × 1010 Ω cm, whereas dielectric constants of AC were between 2 × 105 and 2 × 106.

In this paper, by using the microwave irradiation, the dehydration curves of santite (KB5O8·4H2O) were obtained and modeled. By using a different mathematical model, the kinetic parameters of the dehydration process were determined. The dehydration of santite was completed at 180, 105 and 60 min for 360, 600 and 800 W, respectively. The characterization techniques of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy were applied to the obtained santite mineral and dehydrated santite mineral. From the obtained XRD analysis, santite, its powder diffraction file number is 01-072-1688 transformed into an amorphous phase after the microwave dehydration process. From the FT-IR and Raman analyses, it can be said that partial dehydration was achieved due to the disappearance of structural H2O bands but remaining some hydroxyl bands. For the modeling results, Verma model best fits the experimental data obtained from the dehydration and the dehydration activation energy was calculated as 11.92 kW × g–1.

In this study, fresh and hardened features of gold mine tailings containing cement mortars prepared with various ratios of CuO, SiO2, and Al2O3 nanoparticles were investigated. The setting time, compressive and flexural strength, Differential thermal analysis (DTA)/Thermogravimetric analysis (TG), Brunauer-Emm ett-Teller (BET), X-ray diffraction (XRD), Fourier Transformed Infra-Red (FT-IR), Scanning Electron Microscope (SEM) and water absorption tests were carried out to observe the mechanical, thermal and durability properties of mortars. According to analyses results, the highest increment in the compressive strength was obtained for 0.2 wt% Sio(2) addition as 11.46%. BET results conformed to strength test results and lower ratios of nano-CuO and nano-SiO2 improved the microstructure of mortars when nano-Al2O3 did not show the same effects for all replacement ratios. On the other hand, 2.5 wt% nano-Al2O3 increased the water absorption resistance of mortar up to 45.22% of the reference sample. (C) 2019 Elsevier Ltd. All rights reserved.

In this study, three different types of lanthanum borates, which have the structural formulas of La3BO6, LaBO3 and La(BO2)3, were synthesized, such as diphasic and triphasic, by using the lanthanum source of La2O3 and boron sources of both H3BO3 and B2O3 via a solid-state route. The effects of reactant molar ratio, reaction temperature, time and atmosphere on the production of lanthanum borates were studied. X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Raman Spectroscopy techniques were applied to the synthesized minerals for characterization, and the scanning electron microscopy (SEM) technique was used for the determination of surface morphologies and particle sizes. In addition, the optical and electrical characteristics of synthesized lanthanum borates with the highest XRD scores were investigated.

In this study, sonochemical-assisted magnesium borate synthesis is studied from different boron sources. Various reaction parameters are successfully applied by a simple and green method. X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and Raman spectroscopies are used to characterize the synthesized magnesium borates on the other hand surface morphologies are investigated by using scanning electron microscope (SEM). The XRD analyses showed that the products were admontite [MgO(B2O3)3 · 7(H2O)] with JCPDS (Joint Committee on Powder Diffraction Standards) no. of 01-076-0540 and mcallisterite [Mg2(B6O7(OH)6)2 · 9(H2O)] with JCPDS no. of 01-070-1902. The results that found in the spectroscopic studies were in a good agreement with characteristic magnesium borate bands in both regions of infra-red and visible. According to SEM results, obtained borates were in micro and sub-micro scales. By the use of ultrasonication, reaction yields were found between 84.2 and 97.9%. As a result, it is concluded that the sonochemical approach is a practicable synthesis method to get high efficiency and high crystallinity in the synthesis magnesium borate compounds.

Lithium is the lightest of all metals and the third element in the periodic table. Recent years, lithium salts have become an important input for the energy industry. Lithium carbonate and hydroxides are the basic building blocks of Li-ion battery production. The usage areas of lithium compounds are not limited to only energy; they are also utilized in heavy-duty machines, in the aluminum industry, in nuclear power plants and for glass, ceramics, frit, and coatings in industrial sectors. Lithium has also been found to be very useful in the development of harder, smoother, and more resistant low-temperature glasses, glazes, and enamels. It is also used in very-low-melting-point vitreous compositions like aluminum enamels, colors, fluxes, and glass-seals. The use of lithium also helps in the development of low-expansion bodies, glazes, and glasses. In this study, it is intended to explore the adherence forces in the steel sheet application of different amounts of lithium in enamel frit composition and to examine surface characteristics such as ease of cleaning, gloss, and color. For chemical characterization, X-ray fluorescence (XRF) spectrometry and color measurements were done with a Minolta CM-700d spectrometer device. Bond adherence tests were performed in accordance with the TS EN 10209 standard.

The present study aims to evaluate waste magnesium in magnesium borate synthesis using a novel method of ultrasonic irradiation. For this purpose, waste magnesium is used as a raw material both with boric acid (H3BO3) and boron oxide (B2O3). Syntheses are conducted by directly immersing an ultrasonic probe in a glass reactor, and the reaction parameters are set between 60–80 °C and 5–20 min. Characteristic analyses of the synthesized products are conducted by the techniques of X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, and scanning electron microscope (SEM). Products B2O3 contents and reaction yields are also investigated. Results showed that admontite [MgO(B2O3)3·7(H2O)] and mcallisterite [Mg2(B6O7(OH)6)2·9(H2O)] types of magnesium borates minerals are synthesized. SEM analysis showed that the products particle sizes are approximately between 750 nm and 3.58 μm for mcallisterite, 474 nm and 5.10 μm for admontite. The reaction yields are found between 22 and 51 %.

The hydrothermal synthesis of copper borate compounds [Cu(BO2)2] was studied, and several parameters were found to affect the synthesis. Raw materials, including CuSO4·5H2O, Na2B4O7·5H2O, Na2B4O7·10H2O, NaOH and H3BO3, were used. Reaction temperatures and reaction times between 40 °C and 100 °C and 15 and 240 min, respectively, were used. The as-synthesised copper borate was analysed using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The yields of the reactions were also calculated. Single-phase, nanoparticulate copper borate compounds (Cu(BO2)2) possessing high XRD crystal scores were obtained; the reactions used to obtain these materials were highly efficient. Electrical resistivity and optical absorbance measurements were carried out on the compounds obtained from the highest yielding reactions. The results of this study showed that even using a reaction time of 15 min, copper borate formation was successfully achieved.

In this study, compressive and flexural strength, thermal properties, and pore structure of mortars modified with two types of boron waste and different amounts of CuO nanoparticles were investigated. The binders were prepared with 3% of borogypsum or borax waste and nano-CuO at concentration up to 4%. The setting time, compressive and flexural strength at 3, 7, and 28 days, DTA/TG, XRD, BET, and water absorption tests were carried out, and optimal nano-CuO percentages were determined. It was observed that nano-CuO addition in the range 2%–2.5% can improve mechanical properties, reduce the amount of unreacted portlandite, increase water absorption resistance, and decrease the setting time for borogypsum-containing mortars. The optimum nano-CuO replacement ratio changes between 0.5%–1% for borax waste-containing mortars. The results showed that nano-CuO was able to promote hydration reactions, act as a nanofiller, and provide a kernel for nucleation reactions. En este estudio, se investigaron las resistencias a compresión y flexión, las propiedades térmicas y las estructuras porosas de morteros modificados con dos tipos de residuos de boro y distintas cantidades de nanopartículas de CuO. Los morteros se prepararon con un 3 % de boro-yeso o residuos de boro y nano-CuO, en concentraciones de hasta el 4 %. Se realizaron ensayos de tiempo de fraguado, resistencias mecánicas a 3, 7 y 28 días, ATD/TG, DRX, area BET y absorción de agua y se determinaron los porcentajes óptimos de nano-CuO. Se observó que la adición de nano-CuO en el rango del 2 – 2,5 % mejora las propiedades mecánicas, reduce la cantidad de portlandita sin reaccionar, aumenta la resistencia de absorción del agua y disminuye el tiempo de fraguado en morteros que contienen residuos de boro. Los resultados muestran que el nano-CuO favorece las reacciones de hidratación, actua como nanofiller y proporciona un punto para las reacciones de nucleación.

Boron is known element due to wide range of application areas. Microwave dehydration has more advantages than conventional dehydraion. Differ dehydraion mechanism, higher dehydraion rate and higher level of safety are some of this advantages. Furthermore, most of minerals give better result in microwave for temperature increase. Particle size, microwave power and sample mass are parameters which effect to dehydration directly. Structure of tincalconite is suitable for the investigation of dehydration behavior by microwave because of their five moles of crystal water. Tincalconite is a type of sodium borate mineral which has a white color, trigonal system and molecule formula of Na2B4O7•5H2O. Tincalconite contains 48.8% of boron oxide(B2O3) and 29.47% of structural water. In this study, dehydration behavior of tincalconite was studied with using microwave irradiation with the power level of 180 and 360 W. The kinetic parameters of reaction were determined by using the dehydration kinetic models of Lewis, Henderson and Pabis and Wang and Singh. Tincalconite and dehydrated tincalconite characterized by the techniques of X-ray diffraction (XRD) and Raman spectroscopy. According to the results obtained tincalconite was dehydrated successfully at the microwave power level of 360 W at 14 min, on the contrary at 180 W, only the 68% of the structural water was dehydrated. Among the models, which are applied only at 360 W, Wang and Singh model best fits the data with the coefficient of regression (R2) value of 0.9965.

Besides that today's technology provides lots of developments and benefits, it also causes environmental pollution problems. Preventing environmental pollution and cleaning of pollutants are very important issues in terms of life. The first aim of this study is the synthesis and characterization of a geopolymer, which has a porous structure, from Bergama gold mine tailings. In this way, it is desired to eliminate the negative environmental effects caused by the gold mine waste. For this purpose, geopolymer samples were synthesized in accordance with the experimental program which was designed by Design Expert Trial 7 and optimum geopolymer sample was determined by Central Composite Inscribed (CCI) design method. The second aim of this study is to use the synthesized geopolymer sample in the adsorption of Lead (Pb2+). For this reason, various adsorption studies (pH, temperature, concentration, etc.), isotherm and kinetic studies have been done. X-ray fluorescence spectrometer (XRF), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscope-Energy-dispersive X-ray (SEM-EDX) and Brunauer–Emmett–Teller (BET) analyses were carried out for the raw materials and geopolymer characterization during the studies. ICP-OES device was used in adsorption studies. The experimental results showed that Pb2+ removal by gold mine tailings based geopolymers was best fitted to Langmuir isotherm model (R2 = 0.999) and pseudo second order kinetic models (R2 = 0.993).

The rapid consumption of natural sources due to the technological development brings environmental and economic problems and makes usage of alternative sources obligatory. Fly ash is one of an industrial waste that can be used as alumina silicate source for geopolymerization. In this study, fly ash based geopolymer was synthesized by Alkali Fusion Method. The experimental set up was designed by Design Expert Trial 7 program and the optimum geopolymer synthesis conditions including additional Al2O3 ratio, curing temperature were determined by Central Composite Inscribed Design (CCI) Method. Also, ANOVA analysis and optimization were carried out. X-ray fluorescence spectrometer (XRF), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscope-Energy-dispersive X-ray (SEM-EDX) and Brunauer–Emmett–Teller (BET) analyzes were applied for the characterization studies of the raw materials and optimum geopolymer sample. According to optimization and analysis results, the optimum Al2O3 addition (%) and curing temperatures were determined as 70.76% and 36.75 °C, respectively. The degree of geopolymerization reaction for optimum geopolymer sample was found as 97%.

Boron minerals, considered future essential materials, can be used as raw materials in the production of boron carbide. In this study, boron carbide, the hardest material after diamond and cubic boron nitride, is characterized and the neutron shielding behavior is investigated. The characterization and structural evaluation of the boron carbide sample was performed using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Fourier Transform Infrared Spectroscopy (FT-IR) and Raman Spectroscopy. In addition, a neutron Howitzer was used to measure the neutron permeability of boron carbide samples of various thicknesses. The sample composed of 12.5 g of boron carbide powder and 3 g of Wax® had the lowest neutron permeability rate (62.1%). Pellet 3 had the smallest total macroscopic cross section of boron carbide particles, 0.722 ± 0.0071 cm−1.

The aim of this study was to synthesize zinc borate using zinc oxide, reference boric acid, and reference zinc borate (reference ZB) as the seed, and to investigate the effects of modifying agents and reaction parameters on the hydrophobicity and yield, respectively. The reaction parameters include reaction time (1–5 h), reactant ratio (H3BO3/ZnO by mass: 2–5), seed ratio (seed crystal/(H3BO3+ZnO) by mass: 0–2wt%), reaction temperature (50–120°C), cooling temperature (10–80°C), and stirring rate (400–700 r/min); the modifying agents involve propylene glycol (PG, 0–6wt%), kerosene (1wt%–6wt%), and oleic acid (OA, 1wt%–6wt%) with solvents (isopropyl alcohol (IPA), ethanol, and methanol). The results of reaction yield obtained from either magnetically or mechanically stirred systems were compared. Zinc borate produced was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and contact angle tests to identify the hydrophobicity. In conclusion, zinc borate is synthesized successfully under the optimized reaction conditions, and the different modifying agents with various solvents affect the hydrophobicity of zinc borate.

In this study, the nuclear radiation permeability properties of various boron minerals are evaluated because of their high neutron absorption and lowest transmission properties. Because of these properties boron minerals can be used at the area of neutron shielding. X-ray diffraction (XRD) analyses are done for the identification of the minerals, and then their B2O3 contents are determined experimentally. In addition, X-ray florescence (XRF) analyses are made for quantitative determination of calcium, iron, zinc and arsenic contents. The methods of Differential Thermal Analysis, Thermal Gravimetry (TG/DTA) and Differential Scanning Calorimeter (DSC) are used for obtaining the enthalpy and weight changes with temperature. Additionally, neutron permeability experiments are conducted. From the experimental results, the highest boron oxide content was found in clay containing colemanite. Iron, zinc and arsenic contents were not affecting the neutron shielding. The lowest permeability is provided by the kurnakovite mineral. Also it is observed that all of the minerals show an increase in their permeability in 12 years. It can be stated that boron minerals, specifically kurnakovite, is determined to yield the lowest neutron permeability value and therefore, the use of these materials for neutron shielding would be suitable.

This study investigated the use of solid waste fly ash in the production of lightweight concrete. Fly ash is an industrial waste obtained from the coal-fired thermal generating power plant and it is used in the production of additive construction materials. In Turkey more than 15 million tonnes of fly ash is produced each year, but only a small amount is utilised. The industrial waste fly ashes used in this study came from the power plant at Iskenderun Sugozu, Cayirhan, Tuncbilek and Seyitomer. Lightweight aggregate manufactured from the fly ash and Na-bentonite was used in a pelletisation process. The lightweight concrete manufactured from fly ash aggregate was analysed in terms of the slump and density of fresh concrete and the density, compressive strength and tensile splitting strength of hardened concrete. In the present study, the effects of fly ash aggregates from different power plant when used for lightweight concrete production purposes were investigated and the results obtained were quite satisfactory for the related design requirements.

Turkey has 955,297 thousand tonnes of B 2 O 3 reserves which correspond to 72.1% of the world. Colemanite (Ca 2 B 6 O 11 ·5H 2 O), ulexite (NaCaB 5 O 9 ·8H 2 O) and borax (tincal) (Na 2 B 4 O 7 ·10H 2 O) are the most important boron minerals that are used in production of boric acid and different kinds of borates. During these production processes, boron including wastes form and these wastes pollute the environment. To minimize the pollution caused by these wastes, they are evaluated in different kinds of processes such as cement and concrete production. Borogypsum is one of the boron wastes that is used in cement mortar production. In this study the aim was to compare the calcined and non-calcined borogypsum addition to clinker and also investigate its effects on cement mortar. Moreover, to see how borogypsum addition affected the cement properties, different ratios of borogypsum between 1% and 7% were used. Also setting time and consistency analyses were applied to fresh mortar; compressive strength and splitting tensile strength of 3, 7, and 28 days were investigated according to the Turkish Standard (TS EN 196-1). X-ray diffraction (XRD) analysis was realized for characterization of the chemical structure of 28-days mortars. 3% was the ratio at which the optimum results were obtained for both calcined and non-calcined borogypsum.

In today's automotive industry in order to protect car bodies from corrosion, spray or immersion type zinc phosphating processes are applied. In both types, nickel and chromium are widely used though they are harmful to human health and environment. In this study, car body's corrosion performance, coated by no nickel (0 ppm) and low nickel (100, 200, 300 ppm) immersion type zinc phosphating (without chromium passivation) processes, are compared to the bodies that are coated by spray and immersion type processes including nickel (500–700 ppm) and chromium. After analyzing coating weight, composition, morphology of the crystals and salt spray test corrosion performance of car bodies specimens coated by no nickel and low nickel processes are as good as the ones coated by spray and immersion phosphating processes including nickel and chromium. In developing environment consciousness, it is inevitable to favor no nickel or low nickel processes since they give no harm to nature and human health.

Borogypsum, which consists mainly of gypsum crystals, B2O3 and some impurities, is formed during the production of boric acid from colemanite, which is an important borate ore. In this study, the effect of borogypsum and calcined borogypsum on the physical properties of ordinary Portland cement (OPC) has been investigated. The calcination temperature and transformations in the structures of borogypsum and natural gypsum were determined by differential thermal analysis (DTA), thermogravimetric analysis (TGA) and X-ray diffraction (XRD) techniques. Thermal experiments were carried out between ambient temperature and 500 °C in an air atmosphere at a heating rate of 10 °C min−1. After calculation of enthalpy and determination of conversion temperatures, borogypsum (5% and 7%), hemihydrate borogypsum (5%) and natural gypsum (5%) were added separately to Portland cement clinker and cements were ground in the laboratory. The final products were tested for chemical analysis, compressive strength, setting time, Le Chatelier expansion and fineness properties according to the European Standard (EN 196). The results show that increasing the borogypsum level in Portland cement from 5% to 7% caused an increase in setting time and a decrease in soundness expansion and compressive strength. The cement prepared with borogypsum (5%) was found to have similar strength properties to those obtained with natural gypsum, whereas a mixture containing 5% of hemihydrate borogypsum was found to develop 25% higher compressive strength than the OPC control mixtures at 28 days. For this reason, utilization of calcined borogypsum in cement applications is expected to give better results than untreated borogypsum. It is concluded that hemihydrate borogypsum could be used as a retarder for Portland cement as an industrial side. This would play an important role in reducing environmental pollution.

Magnesium borates are significant compounds due to their advanced mechanical and thermal durability properties. This group of minerals can be used in ceramic industry, in detergent industry, and as neutron shielding material, phosphor of thermoluminescence by dint of their extraordinary specialties. In the present study, the synthesis of magnesium borate via hydrothermal method from sodium borates and physical properties of synthesized magnesium borate minerals were investigated. The characterization of the products was carried out by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and Raman spectroscopies, and differential thermal analysis and thermal gravimetry (DTA/TG). The surface morphology was examined by scanning electron microscopy (SEM). B2O3content was determined through titration. The electrical resistivity/conductivity properties of products were measured by Picoammeter Voltage Source. UV-vis spectrometer was used to investigate optical absorption characteristics of synthesized minerals in the range 200–1000 nm at room temperature. XRD results identified the synthesized borate minerals as admontite [MgO(B2O3)3·7(H2O)] with code number “01-076-0540” and mcallisterite [Mg2(B6O7(OH)6)2·9(H2O)] with code number “01-070-1902.” The FT-IR and Raman spectra of the obtained samples were similar with characteristic magnesium borate bands. The investigation of the SEM images remarked that both nano- and microscale minerals were produced. The reaction yields were between 75.1 and 98.7%.

In this study, zinc borate (ZB) was synthesized by reacting zinc oxide and boric acid in the presence of standard ZB (w/w, in terms of boric acid) in order to promote crystallization. The effects of seed, H3BO3/ZnO (boric acid/zinc oxide) ratio, reaction time, water volume, reaction temperature and cooling temperature on yield were investigated for pilot-scale equipment. The results indicated that the addition of seed (w/w) to a saturated solution of reactants increased the yield of the reaction. The results of reaction yields obtained from either magnetically or mechanically stirred systems were compared. At various reaction times, the optimal yield was 86.78 % in a saturated aqueous solution. The products were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and Thermogravimetric / Differential Thermal Analysis (TG/DTA). The results displayed that ZB was successfully produced under the optimized reaction conditions and the product synthesized had high thermal stability.DOI: http://dx.doi.org/10.5755/j01.ms.19.2.4432

Magnesium borates are one of the major groups of boron minerals that have good neutron shielding performance. In this study, dehydrated magnesium borates were synthesized by solid-state method using magnesium oxide (MgO) and boron oxide (B2O3), in order to test their ability of neutron shielding. After synthesizing the dehydrated magnesium borates, characterizations were done by X-ray Diffraction (XRD), fourier transform infrared (FT-IR), Raman spectroscopy, and scanning electron microscopy (SEM). Also boron oxide (B2O3) contents and reaction yields (%) were calculated. XRD results showed that seven different types of dehydrated magnesium borates were synthesized. 1000°C reaction temperature, 240 minutes of reaction time, and 3 : 2, 1 : 1 mole ratios of products were selected and tested for neutron transmission. Also reaction yields were calculated between 84 and 88% for the 3 : 2 mole ratio products. The neutron transmission experiments revealed that the 3 : 2 mole ratio of MgO to B2O3neutron transmission results (0.618–0.655) was better than the ratio of 1 : 1 (0.772–0.843).

The physical and mechanical properties of monocrystals Bi 2 Te 3 , alloyed by two kinds of impurity are investigated: being easy diffusionable and hard diffusionable. Easy diffusibility of the additive (nickel, iron, silver, copper) at the certain parities (ratio) inside quintet and in among slide space can consolidate or “to loosen” layers.

The level-to-level and island growth of nano-layers: copper, nickel and boron realizes spontaneously between the layers Te1-Te1 in the process of the directed crystallization of bismuth telluride (doped by easily diffusing impurities). This was proved by the electron-microscopic photos of the chipped surface (0001) Bi2Te3, Bi2Te3 and Bi2Te3 . The wide set of island sizes 50-200 nm was revealed. The appearance nature of nano-layers, islands and their enlargement in the interlaminar space of the layered crystal of bismuth telluride is the same as on the open surfaces of the systems semiconductor-metal. The two-dimensional islands, which combining form the wetting layer of nano-thickness appear on the initial steps of the growth. It is established, that the copper layers, nano-sized by the height, are charged with extremal behavior of Hall thermoelectromotive force and other kinetic parameters Bi2Te3 . The temperature dependencies of coefficients of Hall, electroconductivity, mobility and other kinetic parameters revealed the oscillation character. These extremums can be connected with the consecution of the phase transfers, known as order-disorder transfers, connected with positional order. The anomal increase of the mobility of the charge carriers (more, than in 5 times) in the direction along axes of the (0001) Bi2Te3 layers at the temperature 105K is observed so it will be a great improvement that can be used in nano satellites.