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The plasma electrolytic borocarbonitriding (PEB/C/N) process on pure iron was carried out in 25% borax solution with glycerine and carbamide additives under different discharge time at 360V. The morphology and structure of PEB/C/N hardened layers were analyzed by SEM and XRD. The hardness profiles of hardened layers were measured by microhardness test. Corrosion behavior of PEB/C/N layers was evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Their wear performance was carried out using a pin-disc friction and wear tester under dry sliding test. The PEB/C/N samples mainly consisted of -Fe, Fe2B, Fe3C, FeN, FeB, Fe2O3 and Fe4N phases, and the Fe2B phase was the dominant phase in the boride layer. It was found that the thickness of boride layer increased with the discharge time and reached 14m after 60min treatment. The microhardness of the boride layer was up to 2100HV, which was much higher than that of the bare pure iron (about 150HV). After PEB/C/N treatment, the corrosion resistance of pure iron was slightly improved. The friction coefficient of PEB/C/N treated pure iron decreased to 0.129 from 0.556 of pure iron substrate. The wear rate of the PEB/C/N layer after 60min under dry sliding against ZrO2 ball was only 1/10 of that of the bare pure iron. The PEB/C/N treatment is an effective way to improve the wear behavior of pure iron. [ABSTRACT FROM AUTHOR]

Salinity affects over 33% of irrigated farmland globally. Developing a low-cost, safe, and effective material as a soil salinity mitigation option would be of significant importance. This study proposed to synthesize a hydrogel using liquefied biomass from sugarcane bagasse, polyvinyl alcohol, and sodium tetraborate decahydrate. The effectiveness of the produced hydrogel in mitigating soil salinity was evaluated based on an incubation experiment at two salinity levels (5 and 10 dS m-1). The experiment was conducted by mixing liquefied hydrogel with soil at four application rates (0, 1, 2, and 3% w/w) with three replications. Porewater and soil samples were tested for pH and electrical conductivity (EC). Soil samples were also analyzed for selected cations and anions. The results demonstrated that hydrogel significantly reduced porewater EC at both 5 and 10 dS m-1 salt solutions. In addition, hydrogel reduced Cl-, P, Ca2+, and Al3+ concentrations in soil samples with maximum reductions observed from 3% hydrogel treatment. However, pH of porewater showed a consistent increase with hydrogel application. The application of hydrogel also increased NH 4 –N at high salt level. Overall, hydrogel has shown promising results in reducing soil salinity and could potentially be used as a soil amendment for saline soils. [Display omitted] • Liquefied cellulose was prepared using sugarcane bagasse. • Hydrogel was synthesized using liquefied cellulose. • Incubation experiments were conducted using hydrogel on saline soils. • Hydrogel significantly reduced salinity in porewater and soil samples. • Hydrogel reduced Cl-, Ca2+, and Al3+ from salt affected soils. [ABSTRACT FROM AUTHOR]

The utilization potential of citric acid, sodium tetraborate decahydrate and sodium triphosphate pentabasic to control fresh state properties of sodium silicate-activated alkali-activated slag cements (AASC) has been studied. The early structural build-up, reaction kinetics, pore solution chemistry, setting behavior, and hardened properties such as microstructure, pore structure, and mechanical properties of AASC with these chemicals were investigated. Test results showed that early structural build-up, reaction kinetics and setting behavior of AASC can be well controlled by using these chemicals. The citric acid was found the most effective admixture to prolong the setting times of AASC; however, it caused a dramatic decrease in mechanical properties. On the other hand sodium triphosphate pentabasic could provide a slight delay in setting times, while sodium tetraborate decahydrate prolonged the setting times significantly without any detrimental effect on the mechanical properties. [ABSTRACT FROM AUTHOR]

In this study, the effect of accumulative roll bonding (ARB) process on the electrochemical behavior of pure copper in 0.01 M borax solution has been investigated. The microhardness tests showed that by implementing the ARB process the values of microhardness improve with increasing the number of ARB cycles. Moreover, a drastic increase of microhardness was seen (∼100%) after the second ARB cycle. Potentiodynamic polarization plots and electrochemical impedance spectroscopy (EIS) measurements showed that increasing the number of ARB cycles offer better conditions for forming the passive films. In the Mott–Schottky analysis, no evidence for n-type behavior was obtained, indicating that the oxygen vacancies and the copper interstitials do not have any significant population density in the passive films. Also, this analysis revealed that with increasing the number of ARB cycles, the acceptor density of the passive films decreased. [ABSTRACT FROM AUTHOR]

Thesolubility and the metastable zone width of sodium tetraboratedecahydrate in solutions containing lithium chloride have been measuredat temperature a range of (20 to 35) °C. It is found that thelithium impurity has a salt-in effect on the solubility of sodiumtetraborate decahydrate. The metastable zone width broadens with anincrease of the impurity concentrations. This increase can be attributedto the absorption mechanism on the crystal surface. The apparent nucleationorder of sodium tetraborate decahydrate with and without impuritywas calculated by a modified regression method. The results show thatthe addition of lithium impurity has no great effect on the apparentnucleation order of sodium tetraborate decahydrate. [ABSTRACT FROM AUTHOR]

Abstract: Flocculation behavior of two clay rock samples with different dolomite and clay mineral (smectite) contents was examined using a non-conventional, medium-anionic polyacrylamide-based flocculant in borax solutions. The samples were representative of two major types of gangue material discarded from the borax processing plant at Kirka/Turkey as borax-saturated tailings stream which present serious disposal problems from technical and environmental points of view. The effect of the dissolved borax concentration by itself, and the effects of Ca2+ and Mg2+ ions at a constant borax concentration of 3% w/v were investigated with dispersions flocculated at the buffered pH9.4. Flocculation efficiency was mainly assessed by the supernatant turbidity. Increasing the borax concentration decreased the supernatant turbidity. The effect was attributed to the reduced negative electric field around the dolomite and clay mineral particles due to the high ionic strength and the adsorption of sodium cations on the surfaces of the clay mineral particles, facilitating the hydrogen bonding of the amide groups of the flocculant. Ca2+ ions were essential for improving the floc formation and obtaining clear supernatants, but Mg2+ ions were detrimental to floc formation and turbidity removal. Positively-charged adsorbed calcium-hydroxo species on the particles should have promoted stronger salt linkages with the negative pendant groups of the flocculant. The adverse effect of Mg2+ was attributed to its higher hydration energy and the likely precipitation of Mg(OH)2 on particle surfaces. FTIR studies provided some supporting evidence for the suggested mechanisms of flocculant adsorption. [Copyright &y& Elsevier]

Abstract: Selecting an appropriate paper deacidification agent is very important for the deacidification of paper. The use of three deacidification agents (i.e., iso-butylamine, calcium propionate, and borax) is studied for the deacidification of paper using the immersion treatment by investigating the paper surface pH, alkaline residue, paper whiteness, strength, and other performance indicators. Results show the deacidification by borax solution not only results in the promotion of a proper pH range, high level of alkali reserves, and ignorable influence to paper appearance, but also to the enhancement of the mechanical intensities of paper even after artificial aging. Supercritical carbon dioxide (CO2SCF), as a solvent system, is used in the deacidification of acidic papers using the borax solution of water and alcohol. CO2SCF improved the deacidification process by significantly improving the pH value and the base residual value. The borax in supercritical fluids can be better combined with cellulose hydroxyl to improve the mechanical properties of paper substantially. The treatment of borax in CO2SCF could be an alternative for acidic papers. Aside from improving the pH and depositing a sufficient alkaline residual, CO2SCF also strengthens the mechanical properties of treated papers. [Copyright &y& Elsevier]

Abstract: A ceramic coating was formed on the surface of AZ31 magnesium alloy by plasma electrolytic oxidation (PEO) in the silicate solution with and without borax doped. The composition, morphology, elements and roughness as well as mechanical property of the coating were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and reciprocal-sliding tribometer. The results show that the PEO coating is mainly composed of magnesia. When using borax dope, boron element is permeating into the coating and the boron containing phase exist in the form of amorphous. In addition, the microhardness and compactness of the PEO coating are improved significantly due to doped borax. [Copyright &y& Elsevier]

In the present work, membrane electrolysis of nearly saturated borax solution prepared from borax pentahydrate (Na2B4O7.5H2O) was studied. Monolayer cation-exchange membrane (Nafion 551) was used as a separator in a two-compartment electrolysis cell for the production of sodium hydroxide and boric acid. The anolyte concentration was adjusted in order to obtain a Na2O/B2O3 mol ratio of 0.1 by dissolving boric acid and borax pentahydrate together. Experiments were performed in continuous operation mode by feeding nearly saturated borax solution. The effects of different catholyte concentrations (10, 20, and 30% NaOH) on the current efficiency and the specific energy consumption were calculated and the quality of boric acid products was determined. [ABSTRACT FROM AUTHOR]

The solubility and ultra solubility of borax decahydrateboth inpure and impure solutions have been determined in the temperaturerange from (0 to 30) °C by means of the conventional polythermalmethod using the laser technique. The metastable zone width and theapparent nucleation order of borax were calculated. The effects andthe action mechanism of KCl on metastable zone property of borax werestudied. It was found that the presence of KCl made an increase inthe solubility and a decrease in the metastable zones of borax. However,the trends in the changes of metastable zone width at low impurityconcentrations were different from high concentrations because ofthe adsorption equilibria on the crystals. [ABSTRACT FROM AUTHOR]

Summary The efficacy of 30% aqueous urea solution, borax powder and spore suspensions of Phlebiopsis gigantea and Trichoderma harzianum against establishment of artificially inoculated Heterobasidion abietinum on Abies cilicica was tested both in the field and in a simulated stump treatment experiment carried out in a growth chamber. In the field, in each of the four selected stands 20 fresh stumps per control agent were treated and 20 stumps were left as untreated controls. In two of the stands, the treatments were applied in June and in the two others in November. Stumps were sampled twice, at 6- and 12-months after treatment. In the growth chamber, 10 log pieces per treatment and control were used, and sampling performed after 6-week incubation. Results of the urea and borax treatments were consistent between the experiments; the mean efficacies were 98.8 and 99.4% in the growth chamber, and 80.2-91.3 and 89.4-90.1% in the two samplings of the field experiment, respectively. Despite the high efficacies of the P. gigantea (85.9%) and T. harzianum (97.5%) treatments in the growth chamber, efficacies of these biological control agents in the field were 47.1-49.2 and 61.3-65.5%, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The sensitive determination of cyanide in wastewaters using modified GC electrode with silver hexacyanoferrate nanoparticles (SHFNPs) immobilized on multiwall carbon nanotube (MWCNT) was reported. The immobilization of SHFNPs on MWCNT was confirmed by transmission electron microscopy (TEM). The TEM image showed that the SHFNPs retained the spherical morphology after immobilized on MWCNT. The size of SHFNPs was examined around 27nm. The GC/MWCNT-SHFNPs was used for the determination of cyanide in borax buffer (BB) solution (pH 8.0). Using square wave voltammetry, the current response of cyanide increases linearly while increasing its concentration from 40.0nM to 150.0μM and a detection limit was found to be 8.3nM (S/N=3). The present modified electrode was also successfully used for the determination of 5.0μM cyanide in the presence of common contaminants at levels presenting in industrial wastewaters. The practical application of the present modified electrode was demonstrated by measuring the concentration of cyanide in industrial wastewater samples. Moreover, the studied sensor exhibited high sensitivity, good reproducibility and long-term stability. [ABSTRACT FROM AUTHOR]

Abstract: (2S)-2-Fmoc-amino-3-(5′-deoxyuridinylamino)-3-oxopropyloxyacetic acid was synthesized from l-serine as a monomer for preparing the second-generation peptide ribonucleic acid with an oxa-peptide backbone (oxa-PRNA). The ether linkage was incorporated to improve the modest solubility in aqueous solution of the original PRNA with an iso-glutamine backbone, without harming the ability of the amino-uridine side chain to switch the anti/syn nucleobase orientation by adding borax. Indeed, CD spectral examinations revealed that the Fmoc-protected oxa-PRNA uridine monomer (Fmoc-oxa-PRNA(U)), synthesized in three steps, switched the nucleobase orientation from anti to syn in phosphate buffer upon addition of borax. Homo-12mers of oxa-PRNA(U) with and without Arg end caps were prepared in moderate yields by the Fmoc solid-phase synthesis. Both of the N- and C-terminus-capped oxa-PRNA(U) 12mers thus synthesized were shown to hybridize with the complementary DNA 12mer (d(A12)) with stabilities comparable to that observed for the natural pair. [Copyright &y& Elsevier]

Cotton stalks mill were converted to liquid products by using organic solvents (methanol, 1-butanol, and 2-butanol) with catalysts (5 or 10% borax or ulexite) and without catalyst in an autoclave at temperatures of 540, 560, and 580 K. The liquid products were extracted by liquid-liquid extraction (benzene and diethyl ether). The yields from supercritical methanol (10% borax), 1-butanol (10% borax), and 2-butanol (10% borax) conversions were 54.1, 66.8, and 28.0 (at 580 K), respectively. In the noncatalytic run with methanol was 37.4 at the same temperature. [ABSTRACT FROM AUTHOR]

Abstract: Surface oxide films were grown on 99.99% copper and brass (copper–zinc alloy, Cu77Zn21Al2) in 0.1molL−1 borax solution at open circuit potential and were characterized using various experimental techniques. The composition of the passive films formed in situ on the different materials was studied using differential reflectance spectroscopy. The thickness of the oxide layers on copper and brass was compared by chronopotentiometric curves and potentiodynamic reductions. The electrical properties of each oxide were analyzed by means of electrochemical impedance spectroscopy. Their influence on the oxygen reduction reaction was also investigated using voltammetry hydrodynamic tools such as the rotating disk electrode. The results show that the incorporation of Zn to Cu in brass changes the composition and the thickness of the surface film. The films grown on brass tend to be thicker but less resistive and Zn compounds incorporate to the film. This is supported by results from reflectance and impedance spectroscopy. The kinetics of oxygen reduction is strongly inhibited on oxidized electrodes, particularly in the case of brass. The global number of exchanged electrons remains close to four and seems to be independent of the presence of surface oxides. [Copyright &y& Elsevier]

The overall growth kinetics of ammonium pentaborate, borax decahydrate, and boric acid crystals in pure solutions were analyzed using a two-step mass transfer model. Four different linear expressions of the two-step mass transfer model (TSM), which include the widely used expressions of Sobczak and Karpinski, were discussed. The influence of linearization for an assumed second-order reaction kinetics on the mass transfer and reaction steps was studied for various crystallization systems with overall growth kinetic order ranging from 1 to ≥2. The overall growth kinetics of ammonium pentaborate and borax decahydrate were used to study the effect of linearization as a function of temperature and seed size. The complexities in using the linearized TSM expression to predict the mechanism of the crystal growth process in pure solutions were discussed. A Type 3 expression of Karpinski that successfully represents the overall crystal growth kinetics was determined to be successful in representing two-step growth of borax decahydrate and ammonium pentaborate crystals. Type 1 and Type 4 expressions were determined to be inappropriate for the studied crystallization systems, because they either poorly fit the growth kinetics or produce kinetic parameters without physical meaning. The Sobczak expression well-represents the overall crystal growth kinetics of second order or more, and the Karpinski expression was determined to be successful in representing the overall crystal growth kinetics of order near or equal to unity. [ABSTRACT FROM AUTHOR]

Abstract: The duplex copper oxide layer formation process in 0.1M borax solution has been investigated using different potential/time programs, open circuit potential decay, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM). The importance of time in the stability attained by the different oxide species was underscored. The diffusional processes involved in the duplex layer formation and oxide thickness values dependent on experimental conditions were characterized and estimated respectively through EIS data. [Copyright &y& Elsevier]

The article offers a study regarding the photoelectrochemical copper (Cu) electrode behavior in buffered borax solutions with BTA-type inhibitors. The study employed materials and methods including photoelectrochemical technique, measurement of Cu electrode photoresponse in buffered borax solutions. Results show that Cu electrode photoresponse in buffered borax solutions with BTA exhibits n-type response in anodic polarization.

Abstract: Effects of sodium nitrite–borax blend on low carbon steel corrosion in industrial water medium at various temperatures, various inhibitors concentration of sodium nitrite and borax and at various rotational speeds of the specimens have been studied by gravimetric and polarization measurements. Optimization of the three variables was made and correlating the results obtained by using Box–Wilson statistical method. The process was considered as adsorption of inhibitor ions in oxide layer which form a passive film on the metal surface. The Langmuir isotherm was found to be the best description for the adsorption process. Thermodynamic parameters were evaluated and discussed. [Copyright &y& Elsevier]

Conventional glass-ionomer cements with varying amounts (5-15%) of borax (Na2B4O7.10H20) as modifier were prepared. These mixtures were spatulated with an aqueous solution of polyacrylic acid with a powder to liquid (P/L) ratio of 1.5:1. Properties such as working time, setting time, compressive strength, diametral tensile stength, solubility and fluoride release of these cements were determined. It was observed that the working time and setting time of the resultant cements shortened with the addition of borax. Certain physical properties such as compressive and diametral tensile strength, solubility and disintegration of these glass-ionomer cements deteriorated with borax addition but fluoride release from them was unaffected. [ABSTRACT FROM AUTHOR]