Boron Absorption Research Articles

Utilizing chicken manure incineration ash as a phosphorus and silicon source to mitigate boron absorption in barley grown on boron-contaminated soil

Excessive boron (B) levels in soil can lead to toxicity in plants, impacting their growth and productivity. Effective strategies to reduce B uptake are important for improving crop performance in contaminated soils. This experiment aimed to investigate the effects of chicken manure incineration ash (CMA) and triple superphosphate (TSP) on B uptake in barley plants grown in B-contaminated soil. Before the experiment, the chemical composition and molecular structure of CMA were analyzed using XRF, XRD and SEM. The soil was contaminated with 15 mg kg−1 of B, and both TSP and CMA were applied at rates of 40, 80, and 160 mg kg−1 of phosphorus (P). Neither P source had a significant impact on plant dry weight. However, increasing doses of applied TSP and CMA increased plant P concentration while significantly decreasing B concentration. Particularly with CMA applied at 160 mg kg−1 P dose, plant B concentration decreased to the lowest level of 194 mg kg−1. Increasing P doses led to a slight decrease in plant silicon (Si) concentration. The pH of soil samples taken after the experiment slightly increased with CMA treatments compared to TSP. The available P concentration in soils increased with increasing P doses. The available B concentration decreased with increasing P doses, especially reducing to the lowest level of 2.52 mg kg−1 in soils with a 40 mg kg−1 P, CMA. In conclusion, in addition to the effect of P, the molecular structure of P is also important in reducing B uptake in barley.

Fluorinated borono-phenylalanine for optimizing BNCT: Enhancing boron absorption against hydrogen scattering for thermal neutrons.

Boron-containing compounds, such as 4-borono-phenylalanine (BPA) are used as drugs for cancer treatment in the framework of Boron Neutron Capture Therapy (BNCT). Neutron irradiation of boron-rich compounds delivered to cancer cells triggers nuclear reactions that destroy cancercells. We provide a modeling of the thermal neutron cross sectionof BPA, a drug used in Boron Neutron Capture Therapy (BNCT), to quantify the competing contributions of boron absorption against hydrogen scattering, for optimizing BNCT by minimizing thelatter. We perform the experimental determination of the total neutron scattering cross sectionof BPA at thermal and epithermal neutron energies using neutron transmission measurements. We isolate the contribution related to the incoherent scattering by hydrogen atoms as a function of the neutron energy by means of the Average Functional Group Approximation, and we calculate the probability for a neutron of being absorbed as a function of the neutron energy both for BPA and for its variants where either one or all four aromatic hydrogen atoms are substituted by 19 F, and both for the samples with natural occurrence or enriched concentration of 10 B. While referring to the already available literature for in vivo use of fluorinated BPA, we show that fluorine-rich variants of BPA increase the probability of neutrons being captured by the molecule. As the higher absorption efficiency of fluorinated BPA does not depend on whether the molecule is used in vivo or not, our results are promising for the higher efficiency of the boron neutron capturetreatment. Our results suggest a new advantage using fluorinated compounds for BNCT, in their optimized interaction with neutrons, in addition to their already known capability to be used for monitoring and pharmacokinetics studies using 19 F-Nuclear Magnetic Resonance or in 18 F-Positron EmissionTomography.

A promising modified polyvinyl chloride for adsorption of boron: Preparation, adsorption kinetics, isotherm, and thermodynamic studies

AbstractA new promising N‐methyl‐D‐glucamine modified polyvinyl chloride via methyl glycinate linker (PVC‐MG‐NMDG) was designed to extract boron from tourmaline ore from the Sikait area in the South Eastern Desert of Egypt, which assays 10.43% B2O3. Specifications for PVC‐MG‐NMDG composite were executed successfully utilizing sundry approaches, such as FT‐IR, XPS, GC–MS, TGA, BET, EDX, 13C‐NMR, 1H‐NMR, ICP‐OES, and XRD, which assure an acceptable synthesis of PVC‐MG‐NMDG. Optimized factors like pH, agitation time, primary boron concentration, composite dose, co‐ions, eluting agents, and temperature have been improved. At ambient temperature, pH 9, 10 min of agitation, and 0.0138 mol/L boron ions (150 ppm), the PVC‐MG‐NMDG composite has a 25 mg/g maximal uptake. The extraction‐distribution isotherm modeling suggests that the Langmuir model, with a theoretical value of 25.38 mg/g, more closely matches the practical value of 25 mg/g than the Freundlich model. The adsorption kinetics of boron ions by PVC‐MG‐NMDG were predicted with high accuracy using a pseudo‐second order kinetic model, yielding a theoretical retention capacity of 27.93 mg/g. The extraction process was predicted, as shown by thermodynamic calculations, exothermic, spontaneous, and optimal extraction at low temperature; the thermodynamic factors controlling ΔS (−0.04 kJ/mol), ΔH (−13.74 kJ/mol), and ∆G values rise from −1.82 kJ/mol at 298 K to −0.19 kJ/mol at 338 K. Boron ions can be eluted from the overloaded composite by 0.5 M H2SO4 with a 95% efficiency rate. It was established that PVC‐MG‐NMDG composite reveals a worthy separation factor to most co‐ions and gives a good separation power. Boric acid with a boron content of 17.23% and purity of 98.56% can be obtained through alkali fusion with NaOH flux and subsequent adsorption using a PVC‐MG‐NMDG composite.Highlights A New modified polyvinyl chloride (PVC‐MG‐NMDG) was successfully prepared. The characteristics of new composite were verified via different techniques. The new composite reached its maximum boron absorption of 25 mg/g at 25°C. The extraction as an exothermic, spontaneous process at low temperature. The new composite has been applied to a real sample of Sikait tourmaline ore.

The Synergistic Effects of AMF Inoculation and Boron Deficiency on the Growth and Physiology of Camellia oleifera Seedlings

Arbuscular mycorrhizal fungi (AMF) symbiosis has been shown to improve the ability to obtain nutrients and resist adverse environmental conditions. However, there are few studies on the functions of AMF in the absorption and accumulation of boron (B). Moreover, it is still unclear whether the root colonization rates of AMF are limited by B deficiency. In this study, Camellia oleifera seedlings were planted in normal and boron-deficient substrates, and the seedlings were inoculated with Funneliformis mosseae or left uninoculated. The growth and physiological indices of C. oleifera seedlings were determined. The results of this experiment indicate that AMF inoculation increased the plant biomass, B content, B accumulation, and antioxidant enzyme activity in both normal and boron-deficient C. oleifera seedlings. Furthermore, boron deficiency resulted in a decrease in the AMF root colonization efficiency and the inhibition of C. oleifera seedlings’ growth and physiological activity. These findings suggest that AMF inoculation could improve the resistance to B-deficiency stress. Additionally, the colonization efficiency of AMF was adversely affected by B deficiency; thus, AMF play a cooperative role with B in the growth and physiological functions of plants. The results provide a theoretical basis for taking measures to solve B-deficiency stress in C. oleifera and other plants’ cultivation.

Transcriptome Analysis in Pyrus betulaefolia Roots in Response to Short-Term Boron Deficiency.

Boron (B) deficiency stress is frequently observed in pear orchards and causes a considerable loss of productivity and fruit quality. Pyrus betulaefolia is one of the most important rootstocks that has been widely used in pear production. The present study confirmed that the boron form of different tissues showed various changes, and the free boron content was significantly decreased under the short-term B deficiency condition. Moreover, the ABA and JA content also significantly accumulated in the root after short-term B deficiency treatment. A comprehensive transcriptome analysis of 24 h B deficiency treatment P. betulaefolia root was performed in this study. Transcriptome results revealed a total of 1230 up-regulated and 642 down-regulated differentially expressed genes (DEGs), respectively. B deficiency significantly increased the expression of the key aquaporin gene NIP5-1. In addition, B deficiency also increased the expression of ABA (ZEP and NCED) and JA (LOX, AOS and OPR) synthesis genes. Several MYB, WRKY, bHLH and ERF transcription factors were induced by B deficiency stress, which may relate to the regulation of B uptake and plant hormone synthesis. Overall, these findings suggested that P. betulaefolia root had adaptive responses to short-term B deficiency stress by improved boron absorption ability and hormone (JA and ABA) synthesis. The transcriptome analysis provided further information for understanding the mechanism of the pear rootstock responses to B deficiency stress.

Green and low-carbon upcycling of ludwigite: Prepared shields against nuclear radiation hazards and shielding mechanism

The complex composition of ludwigite makes its comprehensive usage difficult. Given the rapid development of ores in nuclear shielding materials, ludwigite was proposed to prepare epoxy resin matrix nuclear shielding composites at room temperature, which could achieve green and low-carbon upcycling. The shielding performance of neutron and gamma-ray sources was evaluated using the 241Am–Be neutron source, the Co-60 gamma-ray source and the Evaluated Nuclear Data File (ENDF). Scanning electron microscopy was used to examine the microstructures. Increasing the ludwigite weight and thickness of the shielding composite increases the shielding percentage of the prepared composites. The prepared shielding composites have macroscopic cross-sections of 0.92–1.89 cm−1, which are comparable to SWX-201, which contains 5% boron. Boron absorption and hydrogen elastic scattering are the primary shielding mechanisms for neutron attenuation in 10−11–10−6 MeV. The shielding composites’ gamma-ray shielding performance is comparable to that of water and ordinary concrete. The work is significant not only for using ludwigite but also for the shielding mechanism analysis of complex multi-element composites.

New properties of boron-oxygen dimer defect in boron-doped Czochralski silicon

Silicon doped with boron is the most widely used material in modern microelectronic devices based on p-Si. Therefore, it is important to thoroughly understand boron’s role in the processes of defect-impurity interaction in Si both on growing the material and during operation of devices. In this work, interactions of boron with oxygen in Si are investigated by studying boron absorption intracenter transitions, which are known to be highly sensitive to the local environment. In boron-doped Si, two lines with maxima at 228 and 261.3 cm−1 were detected. The linear dependence of lines intensity on boron concentration and the quadratic on oxygen content testifies that the defect responsible for the lines can be identified as BsO2i. The observed absorption lines correspond to the transitions from the ground to the excited states of boron, which are shifted toward lower frequencies relative to the main transitions due to a deformation perturbation from neighboring oxygen atoms. The activation energy of annealing and ionization energy of defect are determined. The properties of the registered ВsO2i defect differ from the known ВsO2 associated with the light-induced degradation of solar cells by local configuration. The data obtained testify that the ВsO2i defects with different properties can be formed in Si and must be taken into account when developing Si:B-based devices because they can play an important role in charge carrier transfer and affect the electrical and optical parameters of the material.

Biosorption of Boron from Industrial Wastewater by Green Algae Spirogyra sp.

Introduction: Increasing the concentration of Boron in drinking water, wastewater, and irrigation have negative effects on the human environment. This pollution can be partially removed by the application of phytoremediation technologies using algae or aquatic plants. The aim of the current study was to determine the biosorption capacity of the algae Spirogyra sp. for Boron from industrial wastewater and examine the best elimination conditions using different parameters.
 Materials and Methods: In this study, 100 g of fresh algal biomass was collected from the industrial wastewater of a copper mine located in Kerman, Iran.
 At first, algae was selected among various algal species concerning abundance and resistance ability to high concentrations of Boron. Then, removal of Boron by the algal was examined in terms of algae biomass levels (2 and 4 gr), incubation time intervals (2, 12. 24. 48, and 72 hours), and different concentrations of Boron (5, 10, 15, 25, and 100 ppm) on the were examined. The experiment was factorial with a completely randomized design framework and three replications.
 Results: The results presented that the elimination of Boron from industrial wastewater was performed by biomass of algae Spirogyra sp. The maximum Boron absorption was achieved at concentrations of 5 ppm and an incubation time of 12 hours. The absorption of Boron was higher in 4 gr than in 2 gr of algae biomass treatment.
 Conclusion: It can be concluded that algae Spirogyra sp. has a strong potential for boron removal in industrial wastewater containing boron ions.

Nutrient Status of Forage Corn (Zea mays L.) and Fodder Beet (Beta vulgaris L.) Irrigated with Saline Water

ABSTRACT Fertilization management is a requested tool to limit the impact of salt stress on crops grown in saline conditions. The influence of saline irrigation water on the nutrient status of forage corn and fodder beet was studied in sandy soil. The experiments were conducted in containers during two seasons. Five water electrical conductivity levels were tested: 2, 4, 6, 8, and 10 ds.m−1. The water of 0.7 ds.m−1 was considered as a control. The tested salinity levels were obtained by adding sodium chloride (NaCl) to the control water. The results showed that the biomass of forage corn and fodder beet was significantly reduced by water salinity. The nutrient status of the tested crops showed a significant increase in phosphorus (P) contents with water conductivity. The increase in P content exceeded 13% and 11% for corn and fodder beet, respectively, at conductivity level over 4 ds.m−1 compared to control. The plant potassium (K) content was significantly unaffected by saline water. The absorption of micronutrients (iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), and boron (B)) was not significantly depressed by salinity. A disturbance in magnesium (Mg) and calcium (Ca) absorption was noticed on both studied crops. The results reveal that fertilization management can be improved by considering the nutrient status shifting established at the saline conditions.

Increasing media pH contribute to the absorption of boron via roots to promote the growth of citrus

Low pH is an important limiting factor for plant development in the south of China due to problems of acid red soil and boron (B) deficiency. Whereas, there is very limited information on the relationship between media pH and B distribution in plant, the physiological process changed by the interaction of pH and B in citrus growth also unclear. This experiment was conducted on trifoliate rootstock by employing two different concentrations of B (0 or 10 μM B) under three pH levels: pH 4, pH 5, and pH 6. Our results illustrate that low pH inhibite plant growth and cause oxidative stress in the roots, resulting in cell membrane injury. The increase of pH and B addition reduce the accumulation of ROS (O2.- and H2O2) by regulating the activity of Class Ⅲ peroxidases (CIII Prxs). Moreover, increased pH improves the internal circulation of B in plants and decrease the content of lignin and cellulose in cell wall (CW). In summary, our investigation demonstrated that the increase of pH in nutrient solution can accelerate the re-distribution of B by roots to promote citrus growth. The accumulation of B in roots can protect plants from the damage of ROS by regulating the activity of CIII Prxs as well as decrease the content of lignin and cellulose are to promotes roots elongation.

Boron in Ni-Rich NCM811 Cathode Material: Impact on Atomic and Microscale Properties

Doping of Ni-rich cathode active materials with boron is a promising way to improve their cycling stability and mitigate their degradation, but it is still not understood how this effect is achieved and where the boron is located. To receive deeper insights into the impact of doping on atomic and microscale properties, B-doped Li[Ni0.8Co0.1Mn0.1]O2 (NCM811) cathode materials were synthesized by a hydroxide coprecipitation as a model compound to verify the presence and location of boron in B-doped, Ni-rich NCM, as well as its impact on the microstructure and electrochemical properties, by a combined experimental and theoretical approach. Besides X-ray diffraction and Rietveld refinement, DFT calculation was used to find the preferred site of boron absorption and its effect on the NCM lattice parameters. It is found that boron shows a trigonal planar and tetrahedral coordination to oxygen in the Ni layers, leading to a slight increase in lattice parameter c through an electrostatic interaction with Li ions. Therefore, B-doping of NCM811 affects the crystal structure and cation disorder and leads to a change in primary particle size and shape. To experimentally prove that the observations are caused by boron incorporated into the NCM lattice, we detected, quantified, and localized boron in 2 mol % B-doped NCM811 by ion beam analysis and TOF-SIMS. It was possible to quantify boron by NRA with a depth resolution of 2 μm. We found a boron enrichment on the agglomerate surface but also, more importantly, a significant high and constant boron concentration in the interior of the primary particles near the surface, which experimentally verifies that boron is incorporated into the NCM811 lattice.

Production of Ferroboron from Wastes by SHS-metallurgy and influence of Ligatures on the Structure/Properties of Cast Iron

Waste, generated during the industrial process negatively affects the environment, but at the same time it is a valuable raw material and can be used to produce new marketable products. The study of the effectiveness of Self-propagating High temperature Synthesis (SHS) methods, which are characterized by the simplicity of the necessary equipment, the purity of the final product and the high processing speed, is under the wide scientific and practical interest to solve the set problem. The work describes technological aspects of production of ferro boron by the method of SHS - metallurgy from iron-containing wastes of rolled production for alloying of cast iron and results of effect of alloying element on degree of boron assimilation with liquid cast iron. Features of Fe-B system combustion have been investigated and the main parameters to control the phase composition of synthesis products have been experimentally established. Effect of overloads on patterns of cast ligatures formation and mechanisms of structure formation of SHS products was studied. It has been shown that an increase in the content of hematite Fe2O3 in iron-containing waste leads to an increase in the content of phase FeB and accordingly, the amount of boron in the ligature. Boron content in ligature is within 3-14%, and phase composition of obtained ligatures consists of Fe2B and FeB phases. Depending on the initial composition of the wastes, the yield of the end product reaches 91 - 94%, and the extraction of boron is 70 - 88%. Combustion processes of high exothermic mixtures allow obtaining a wide range of boron-containing ligatures from industrial wastes. In view of the relatively low melting point of the obtained SHS-ligature, the positive dynamics of boron absorption by liquid iron is established. According to the obtained data, the degree of absorption of the ligature by alloying gray cast iron at 1450 ° C is 80 - 85%. When combined with the treatment of liquid cast iron with magnesium, followed by alloying with the developed ligature, boron losses are reduced by 5-7%. At that uniform distribution of boron micro-additives in volume of treated liquid metal is provided.

Effect of Different Levels of Borax and Gypsum on Soil Chemical Properties and Yield of Finger Millet (Eleusine corocana L) in Southern Dry Zone of Karnataka

A field experiment was carried out in Kharif 2016 on B-deficient sandy loam soil at College of Agriculture, VC Farm, Mandya to study the effect of graded levels borax (5, 10, 15 and 20 kg ha1) and gypsum (100 and 200 kg ha-1) on yield and soil chemical properties of irrigated finger millet (Eleusine corocana L.) in Southern Dry Zone of Karnataka. A significantly higher grain yield of 45.95 q ha-1 (17.56% higher than the control) and a B:C ratio of 3.06 were also recorded at T12 compared with RDF + FYM (T1). Due to application of borax and gypsum, the pH, EC, and organic carbon content in soil during flowering stage and at crop harvest were non-significant. However, at the flowering and harvest of the crop, the T4 treatment had the lowest pH (7.49 and 7.43, respectively), whereas the T12 (flowering stage) and T10 (after harvest) treatments had the highest pH (7.65 and 7.67, respectively). Higher soil NPK values were detected in all treatments at flowering stage compared to after the crop was harvested. Application of borax 10kg ha-1 + 100 kg gypsum ha-1 along with RDF and FYM had a significantly higher exchangeable calcium content after harvest (6.77 cmol kg-1) than T1 (5.23 cmol kg-1). Sulphur content in soil at flowering stage and after harvest of crop was found to be significant among the treatments due to application of different levels of gypsum. High levels of borax applied treatments, i. e. T5 (T1+20 kg borax ha-1) and T15 (T5 + 200 kg gypsum ha-1) recorded significantly higher content of B at flowering stage (4.18 and 4.09 mg kg-1, respectively) and at harvest of crop (3.88 and 3.68 mg kg-1, respectively) when compared to T1 (1.32 and 1.16 mg kg-1, respectively). Therefore finger millet absorption of boron may be reduced by using borax with a greater dosage of gypsum (200 kg ha-1). As a result, optimising the Ca/B ratio in the soil and plant is critical for increasing irrigated finger millet yields.

Fly ash–GGBS geopolymer in boron environment: A study on rheology and microstructure by ATR FT-IR and MAS NMR

The present study focuses on the use of borax composite sodium silicate activator (B) in place of water glass (S) in the fly ash–GGBS composite (4:1) geopolymerization. The substituent is favoured as it delivers advantages such as increased setting time and workability by mitigating the agglomeration of flocks without affecting the compressive strength of the geopolymer. Microstructural changes of boroaluminosilicate were studied with the help of ATR-FT-IR and MAS NMR. Rheology studies indicated that the borax composite pastes display shear thinning behaviour with low yield stress and fit well with the Bingham model. In-situ ATR-FT-IR spectrum revealed the severing of silica bonds by soluble [BO4] and its incorporation into the silicate backbone resulted in the drop in of Si–O–T asymmetry vibration response. The NMR spectral changes of 29Si,27Al and 11B nuclei environment in geopolymeric tetrahedral network showed that the fraction of [SiO4] and [BO4] increases upon borax addition with the diminished fraction of B3 non-rings without any specific changes in Al coordination. The tetrahedral boron absorption band in the wave numbers at 1380–1310 cm−1 and1134 cm–1is observed in FT-IR and its configuration is compatible in the reaction product.

Radiation synthesis of polyvinyl alcohol/acrylic acid/magnesium oxide composite hydrogel for removal of boron from its aqueous solution

Various compositions of polyvinyl alcohol/acrylic acid Poly(PVA/AAc) hydrogels are prepared using of gamma radiation. The properties of the prepared poly(PVA/AAc) hydrogel and poly(PVA/AAc/magnesium oxide (MgO)) composite hydrogel were characterized by various techniques such as fourier transform infrared (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy. The TEM and XRD patterns of MgO nanoparticles indicate that the MgO with average particle size ranged from 18.11 nm to 45.6 nm. The gel (%) of the prepared poly(PVA/AAc) hydrogel with different contents of AAc increased with increasing both irradiation dose and AAc content. The swelling (%) of poly(PVA/AAc) hydrogel at different irradiation doses and different AAc contents found to be decreased with increasing both irradiation dose and AAc contents. The effect of incorporation of MgO nanoparticles into the poly(PVA/AAc) hydrogel matrix for absorption of boron from aqueous solution under various factors such as different concentrations of boron, different concentrations of MgO, and at different treatment times was investigated. From the study, the modified poly(PVA: AAc/MgO) composite hydrogel with composition (80:20 vol.%/5 wt%) has higher substitution, macroporous structure and characterized by better performance in swelling and boron uptake capacity than poly(PVA/AAc) hydrogel with composition (80/20 vol.%). The high absorption of boron indicates complex formation via ion exchange and chelation between poly(PVA/AAc/MgO) and boron due to the presence of different moieties provided by acrylic–acrylic, acrylic-PVA, and PVA-PVA.

Microalloying of low carbon steel with boron and a method for determining the effective concentration of dissolved boron

Goal. The effect of boron on the properties of steel is considered. It has been established that hardenability improves due to the influence of boron, which is not bound in oxides, nitrides or other compounds. This boron is in solid solution in austenite and is called an “effective” boron. The mechanism of increasing the hardenability of steel due to such boron is associated with inhibition of the occurrence of crystallization centers of ferrite and bainite. Methodology.The effective fraction of boron in dissolved state in austenite is determined by the method of electrochemical phase analysis. The microalloying of low-carbon steel 08kp with boron is tested on industrial heats under conditions of Martin workshop of JSC «Zaporozhstal». Smelting and teeming of steel were performed according to the requirements of operating technology. The input of ferroboron into metal took place while letting out the heats into the ladle after completion of the ferromanganese input. All the experimental heats were blown through in the ladle with argon to appearance of the furnace slag. For microalloying the ferroboron of the grade FB20 was used. At the by-sheet sorting of the experimental ingot of the heat (the average content of boron in the heat - 0,00138%), sampling of metal rolled stock was brought off on 5 horizons by the height. In every sample the chemical analysis for the content of boron was executed in 3th points, corresponding to the edge of roll, ¼ on the width and axis. Results of the chemical analysis are presented in the table 1. At the average content of boron in the heat - 0,00138%, the content of boron was distributed along the height and width of the ingot was distributed from 0,0008% (-0,00058%) to 0,0024% (+ 0,00102%). Results. The technology of microalloying low-carbon steel with boron has been mastered with obtaining a guaranteed content of at least 0,0008%. Putting a ferroboron into the ladle with a flow rate of 0.26 - 0.31 kg / t followed by purging the metal in a ladle with pure argon provides the boron content in the steel 0.0009 - 0.0015%. The absorption of boron during microalloying depends on the fractional composition of boron-containing material. For a fraction of less than 3 mm, assimilation is 29%, and for a fraction of 5-10 mm, 76% of the assimilation values obtained for an optimal fraction of 20-40 mm. Boron in 08kp steel increases the tensile strength by 4.5% and the yield strength by 2.6% compared with the average values of this steel without boron.

Electrical and optical characteristics of boron doped nanocrystalline diamond films

Boron doped diamond is a prospective material which can be used as a conductive and optically transparent thin-film electrode in a variety of optoelectronic applications. In this work, we present the results of the temperature resolved electrical conductivity, optical reflection, transmission and absorption of thin boron doped nanocrystalline diamond films grown by a microwave plasma enhanced chemical vapor deposition. Optical transmittance, reflectance and absorptance properties of layers were studied by a photo-thermal deflection spectroscopy analysis. Raman spectroscopy with various excitation wavelengths was employed for the analysis of nanocrystalline diamond layers. The measured position, shift and broadening of the characteristic boron doped diamond Raman lines were used for the determination of the boron concentration. Correlation between the results of the atomic boron concentration estimated via the Raman analysis and measured electrical conductivity values is presented.

Synaptic silicon-nanocrystal phototransistors for neuromorphic computing

The incorporation of augmentative functionalities into a single synaptic device is greatly desired to enhance the performance of neuromorphic computing, which has brain-like high intelligence and low energy consumption. This encourages the development of multi-functional synaptic devices with architectures that are capable of achieving demanded synaptic plasticity. Here we take advantage of the remarkable optical absorption of boron (B)-doped silicon nanocrystals (Si NCs) to make synaptic phototransistors, which can be stimulated by both optical and electrical spikes. The optical and electrical stimulations enable a series of important synaptic functionalities for the synaptic Si-NC phototransistors, well mimicking biological synapses. It is interesting that the synergy of the photogating and electrical gating of the synaptic Si-NC phototransistors leads to the implementation of aversion learning and logic functions. We show that a spiking neural network based on the synaptic Si-NC phototransistors may be trained for the recognition of handwritten digits in the modified national institute of standards and technology (MNIST) database with a recognition accuracy around 94%. The energy consumption of the synaptic Si-NC phototransistors may be rather low, which should help advance energy-efficient neuromorphic computing.

Boron effect on processing properties of middle-carbon structural steels of the common product range

The object of study is low-alloyed boron-containing structural steels. The research method is analysis of the deoxidation effect on the boron uptake degree and the quality of the metal according to the statistical processing of current production meltings. The objective is to determine the optimum degree of steel deoxidation in order to obtain stable mechanical properties of the finished metal. The distinguishing features of boron steels production have been analyzed. It has been shown that the efficiency of microalloying with boron depends on the deoxidation technology and heat treatment in the production cycle. Under Ilyich Iron and Steel Works of Mariupol (MMKI) conditions, the absence of heat treatment departments for thin rolled products and the limited variability of operations for thick rolled products restricts the possibility of producing boron-containing steels. The structure of boron-containing steels production over the period from 2016 till 2018 has been analyzed. It has been shown that these are mainly medium-carbon structural steels of the common product range, alloyed with manganese and aluminum. In the absence of modern means of secondary treatment, boron microalloying (PB 20, lumps of 10-50 mm in size) is carried out after complete deoxidation of the metal, while the degree of boron absorption is quite substantial and amounts to 77-92%. Using A36 steel as an example, the basic mechanical properties of finished rolled products have been analyzed. The stabilization of mechanical properties within narrower limits and the possibility to reduce the aluminum consumption by 8-10% are considered to be the result of boron positive effect on the steel quality. The optimal content of acid-soluble aluminum in metal should be 0,028-0,032%. Saving aluminum will make it possible to use stronger nitride-forming elements such as titanium to stabilize the quality indicators of the finished metal

Short Term Effects of Dietary Boron on Mineral Status in Dairy Cows*

Aim of this study was to obtain knowledge on boron supplemented diet to mineral status of body fluids and feces in short term nutrition of dairy cattle. A total of 24 healthy Holstein dairy cows were used. The animals were fed with standard ration, and boron at three different doses was added to experimental' diets as boron compound: borax, for 10 days. Boron and other macro and trace minerals were determined in serum, milk, urine and feces samples taken on 0 and 11st days. In this study, there were no overt signs of toxicosis, and a pivotal knowledge was obtained in dairy cattle fed with boron supplemented diet on boron absorption, excretion, and its interaction with other minerals. Boron could not completely absorb from gastrointestinal tract. Urine was the most important excretion way of boron. More less boron was also eliminated by milk. Boron levels in body fluids (serum and milk, p less then 0.000) were increasingly changed based on the dose. Boron, among minerals, provided a striking increase for Ca (p less then 0.003) and Mg (p less then 0.028) levels in serum by increasing absorption of these minerals. This topic is worth evaluating as an alternative approach in the prevention of hypocalcemia in transition cows.