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In our research, boron was added into the Nb-added high strength low alloy (HSLA) H-section steels. The contents of boron added were 4ppm, 8ppm and 11ppm, respectively. The mechanical properties of H-section steels with/without boron were examined by using uniaxial tensile test and Charpy impact test (V-notch). The morphologies of the microstructure and the fracture surfaces of the impact specimens were observed by metalloscope, stereomicroscope and electron probe. The experimental results indicate that boron gives a significant increase in impact toughness, especially in low temperature impact toughness, though it leads to an unremarkable increase in strength and plasticity. For instance, the absorbed energy at -40°C reaches up to 126J from 15J by 8ppm boron addition, and the ductile-brittle transition temperature declines by 20°C. It is shown that boron has a beneficial effect on grain refinement. The fracture mechanism is transited from cleavage fracture to dimple fracture due to boron addition.

Nanodiamonds of different sizes doped with B and N impurities are studied by density functional theory. We find that the most stable sites for the B and N dopants are different. The substitutional B tends to stay in the middle region of a nanodiamond, while the energetically preferable site for N is on the surface of the nanodiamond. The chemical bonding and electronic properties of the B- and N-doped nanodiamonds are also discussed.

In this study, the relationship between the creep ductility and rupture life of 9Cr-1.5Mo steel with boron addition at 600°C was investigated by small punch (SP) creep test from the viewpoint of the modified Monkman-Grant relation. The amount of boron addition ranged from 0.0076wt% to 0.0196 wt%. The general concept of Monkman-Grant ductility for uniaxial creep was introduced and then particularly modified for the SP creep. The microstructure of the steel was observed to analyze the effect of boron addition on the creep ductility and rupture life. Based on the modified Monkman-Grant ductility for SP creep, it was found that the boron addition improved the creep ductility and rupture life of the 9Cr-1.5Mo steel. Also, the relationship between the minimum creep displacement rate and the amount of boron addition was analyzed.

In this study, we investigated stable structures for a transition metal atom–boron (CrB) wheel-like clusters and compared them with their corresponding 3D counterparts by means of density functional theory (DFT). In addition, hydrogen storage capability of the wheel-like system was investigated. All simulations were performed at the B3LYP/TZVP level of theory. We set out a complete route to the formation of CrB wheel-like clusters. Our results showed that, some of the clusters, investigated in this work (CrB_n; n = 4, 6, 7, 8), either prefer to be in a 3D geometry rather than 2D quasi-planar or planar geometry. However, hydrogen doping has an interesting effect on both 2D quasi-planar and 3D geometries of this system. Simply it transforms the 3D structure, first, into a 2D quasi-planar, then a planar geometry. Furthermore, our results show that H–cluster interaction is too high for reversible hydrogen storage for these clusters.

Boron nitride (BN) and Titanium nitrides (TiNs) have been successfully researched recently. In order to analyze the relationship among the Boron, Nitrogen and Titanium, the ternary compounds with an orthorhombic structure Immm- are studied. We further researched on the mechanical, electronic and optical properties of new Immm-B${}_x$Ti${}_{3-x}$N₂ ($x=1,2$). The structures of BTi₂N₂ and B₂TiN₂ are mechanically stable at 0, 50 and 100 GPa. The BTi₂N₂ has the higher cutting resistance and better ductility than the B₂TiN₂. The higher Young’s modulus of B₂TiN₂ indicates the B₂TiN₂ is stiffer than BTi₂N₂. The BTi₂N₂ is harder to compress in the $Y$ direction and the B₂TiN₂ is harder in $Z$ direction. Immm-BTi₂N₂ and B₂TiN₂ have good metallicity at 0 and 100 GPa. Immm-BTi₂N₂ has the higher dielectric function than B₂TiN₂ and the plasma frequency of B₂TiN₂ is bigger than that of BTi₂N₂. We hope our work will provide some help to the experimental work about the technology of the material.

Titanium alloys have poor wear performance, with severe adhesive wear and three-body abrasion being dominant mechanisms. To extend the use of titanium to applications demanding better wear properties, modifications can be made to the alloys. This can include the addition of hard particulates or interstitial strengthening, by increasing the oxygen or nitrogen content. The metal additive manufacturing process of selective laser melting (SLM) has been shown to enable manufacture of these modified titanium alloys in situ. In this study, small amounts of boron and titanium dioxide powders were added to Ti-6Al-4V (Ti64) and processed using SLM. To compare wear performance of these modified materials, reciprocating pin on plate tests in brine solution were performed. Increased oxygen content increased the hardness of the material, which reduced wear. The presence of boron increased wear in the short term but reduced the long-term wear rate. Incorporating of oxygen and boron has been shown to improve the saline solution wear properties of Ti64 against silicon nitride.

Employing a first-principles method in combination with the empirical criterions, we have investigated the site preference of boron (B) and its effect on the mechanical properties of the binary-phase TiAl–Ti₃Al alloy. It is found that B energetically prefers to occupy the Ti-rich octahedral interstitial site, because B is more favorable to bond with Ti in comparison with Al. The occupancy tendency of B in the TiAl–Ti₃Al alloy is the TiAl/Ti₃Al interface $>$ Ti₃Al $>$ TiAl, thus B tends to segregate into the binary-phase interface in the TiAl–Ti₃Al alloy. The charge density difference shows that B at the TiAl–Ti₃Al interface will form strong B–Ti bonds and weak B–Al bonds, leading to the significant increasing of the cleavage energy $({\gamma }_{\mathrm{\text{cl}}})$ and the unstable stacking fault energy $({\gamma }_{\mathrm{\text{us}}})$. This indicates that the presence of B will strengthen the TiAl/Ti₃Al interface, but block its mobility. Further, the ratio of ${\gamma }_{\mathrm{\text{cl}}}$/${\gamma }_{\mathrm{\text{us}}}$ of the B-doped system is 4.63%, 8.19% lower than that of the clean system. Based on the empirical criterions, B will have a negative effect on the ductility of the TiAl–Ti₃Al alloy.

Low-energy protons from the cyclotron in the range of 15–30 MeV and low current have been simulated on beryllium (Be) target with a lead moderator around the target. This research was accomplished to design an epithermal neutron beam for Boron Neutron Capture Therapy (BNCT) using the moderated neutron on the average produced from ⁹Be target via (p, xn) reaction in Adiabatic Resonance Crossing (ARC) concept. Generation of neutron to proton ratio, energy distribution, flux and dose components in head phantom have been simulated by MCNP5 code. The reflector and collimator were designed in prevention and collimation of derivation neutrons from proton bombarding. The scalp-skull-brain phantom consisting of bone and brain equivalent material has been simulated in order to evaluate the dosimetric effect on the brain. Results of this analysis demonstrated while the proton energy decreased, the dose factor altered according to filters thickness. The maximum epithermal flux revealed using fluental, Fe and bismuth (Bi) filters with thicknesses of 9.4, 3 and 2 cm, respectively and also the epithermal to thermal neutron flux ratio was 103.85. The potential of the ARC method to replace or complement the current reactor-based supply sources of BNCT purposes.

The interaction of a mono-energetic neutron beam with a target layer of Boron-10 is studied to characterize the behavior of neutrons and produced charged particles inside the layer. The detection system is modeled through a Monte-Carlo simulation. The quality of the simulation method and controlling parameters is assessed with the response function. The Von Neumann rejection sampling method is used to model the interaction process. The obtained results show high agreement with previous results.

The effect of boron weight percentage in the camphoric carbon target of pulsed laser deposition on the preparation of boron-doped amorphous carbon (a-C:B) films has been studied using standard measurement techniques. XPS results showed the a-C:B films bonding properties almost unchanged at lower Bwt% up to 10 Bwt%, after which it changes with the increase of Bwt%, indicating increasing doping concentration with increase of Bwt% in the target. This phenomenon is further supported by FTIR and Visible-Raman spectroscopy analyses. The variation of bonding and structural properties are also correlated with the optical gap (E_g) and electrical resistivity (ρ) characteristics which are related to successful doping of B for low content of B in the amorphous carbon (a-C) films as the bonding, structural and E_g remain almost unchanged, and the ρ decreased untill the film deposited at 10 Bwt%. Since both the E_g and ρ decrease sharply with higher Bwt%, this phenomenon can be related to the graphitization.

The successful deposition of boron (B)-doped p-type (p-C:B) and phosphorous (P)-doped n-type (n-C:P) carbon (C) films, and fabrication of p-C:B on silicon (Si) substrate (p-C:B/n-Si) and n-C:P/p-Si cells by the technique of pulsed laser deposition (PLD) using graphite target is reported. The cells' performances are represented in the dark I–V rectifying curve and I–V working curve under illumination when exposed to AM 1.5 illumination condition (100 mW/cm², 25°C). The open circuit voltage (V_oc) and short circuit current density (J_sc) for p-C:B/n-Si are observed to vary from 230–250 mV and 1.5–2.2 mA/cm², respectively, and to vary from 215–265 mV and 7.5–10.5 mA/cm², respectively, for n-C:P/p-Si cells. The p-C:B/n-Si cell fabricated using the target with the amount of B by 3 Bwt% shows highest energy conversion efficiency, η = 0.20%, and fill factor, FF = 45%, while, the n-C:P/p-Si cell with the amount of P by 7 Pwt% shows highest energy conversion efficiency, η = 1.14%, and fill factor, FF = 41%. The quantum efficiencies (QE) of the p-C:B/n-Si and n-C:P/p-Si cells are observed to improve with Bwt% and Pwt%, respectively. The contributions of QE are suggested to be due to photon absorption by carbon layer in the lower wavelength region (below 750 nm) and Si substrates in the higher wavelength region. The dependence of B and P content on the electrical and optical properties of the deposited films, and the photovoltaic characteristics of the respective p-C:B/n-Si and n-C:P/p-Si heterojunction photovoltaic cells, are discussed.

This paper reports on the successful deposition of boron (B)-doped p-type (p-C:B) and phosphorus (P)-doped n-type (p-C:P) carbon (C) films, and the fabrication of p-C:B on silicon (Si) substrate (p-C:B/n-Si) and n-C:P/p-Si cells by a pulsed laser deposition (PLD) technique using a graphite target at room temperature. The boron and phosphorus atoms incorporated in the films were determined by X-ray photoelectron spectroscopy (XPS) to be in the range of 0.2–1.75 and 0.22–1.77 atomic percentages, respectively. The cells performances have been given in the dark I–V rectifying curve and I–V working curve under illumination when exposed to AM 1.5 illumination conditions (100 mW/cm², 25°C). The open circuit voltage (V_oc) and short circuit current density (J_sc) for p-C:B/n-Si are observed to vary from 230 to 250 mV and from 1.5 to 2.2 mA/cm², respectively; they vary from 215 to 265 mV and from 7.5 to 10.5 mA/cm², respectively, for n-C:P/p-Si cells. The p-C:B/n-Si cell fabricated using the target with the amount of boron by 3 weight percentages (Bwt%) showed the highest energy conversion efficiency, η = 0.20% and fill factor, FF = 45%. The n-C:P/p-Si cell fabricated using the target with the amount of 7 Pwt% showed the highest η = 1.14% and FF = 41%. The quantum efficiency (QE) of the p-C:B/n-Si and n-C:P/p-Si cells were observed to improve with Bwt% and Pwt%, respectively. The contribution of QE in the lower wavelength region (below 750 nm) may be due to photon absorption by the carbon layer, in the higher wavelength region it was due to the Si substrates. In this paper, the dependence of the boron and phosphorus content on the electrical and optical properties of the deposited films and the photovoltaic characteristics of the respective p-C:B/n-Si and n-C:P/p-Si heterojunction solar cells are discussed.

Segregation of boron on surface has been studied using the periodical calculations within the local density approximation. The obtained segregation energy (enthalpy) of about -1.9 eV is close to the published data of experimental studies and previous cluster semiempirical calculations. The influence of plane-wave basis set cutoff energy and the slab unit cell depth on the value of segregation energy has been investigated.

The aim of the present work is to determine the influence of technologically produced boron surface layers on the friction parameters in the sliding pairs under the conditions of mixed friction. The tribological evaluation included ion nitrided, pack borided, laser borided, quenched and tempered surface layers and TiB₂ coating deposited on 38CrAlMo_5-10, 46Cr₂ and 30MnB₄ steels. Modified surface layers of annular samples were matched under test conditions with counter-sample made from AlSn₂₀ bearing alloy. Tested sliding pairs were lubricated with 15 W/40 Lotos mineral engine oil. The tribological tests were conducted on a T-05 block on ring tester. The applied steel surface layer modification with boron allows surface layers to be created with pre-determined tribological characteristics required for the elements of kinematic pairs operating in the conditions of sliding friction. Pack boronizing reduces the friction coefficient during the start-up of the frictional pair and the maximum start-up resistance level is similar to the levels of pairs with nitrided surface layers.

The mechanism of boron-enhanced diffusion from a thin boron layer deposited on the surface in the case of silicon crystal doping is proposed and investigated. It was supposed that lattice contraction occurs in the vicinity of the surface due to the difference between the atomic radii of boron and silicon. This lattice contraction provides a stress-mediated diffusion of silicon self-interstitials from the near-surface region to the bulk of a semiconductor. Due to the stress-mediated diffusion, the near-surface region is depleted of silicon self-interstitials, and simultaneous oversaturation of this species occurs in the bulk. In this way, a strong nonuniform distribution of silicon self-interstitials in the vicinity of the surface is formed without regard to the large migration length of this species. The oversaturation of the bulk of a semiconductor with nonequilibrium self-interstitials allows one to explain the boron-enhanced diffusion of impurity atoms. The strong nonuniform distribution of these point defects also results in a specific form of boron concentration profile in the vicinity of the surface. Good agreement of the calculated boron profile with the experimental data for the entire doped region was obtained within the limit of the proposed model.

The second-order optical nonlinearity (SON) of thermally poled fused silica was shown for the first time to be significantly improved by the implantation of multi-energy boron (B) ions, and the outcomes were compared with those obtained from the implantation of multi-energy argon (Ar) ions. Second-harmonic (SH) signals in both samples grew roughly linearly as the poling temperature rose. Samples with Ar implants showed a greater increase in SH signal with rising poling temperature. A qualitative explanation for the formation of ${\chi }^{(2)}$ in poled samples can be found in a model of charge hopping and migration through defects. The diminished SH signal in the B-implanted sample is probably caused by the negative charge trapping layer, as well as by B${}_{2\alpha }$ and E${}^{\prime }$ center defects.

Recent advances in the chemistry of main group porphyrin complexes are surveyed. New, unprecedented structural types for porphyrin complexes which have been revealed from the recent reports of boron and tellurium porphyrins are described. Advances in the preparation and reactivity of Group 14 (silicon and tin) and Group 15 porphyrin complexes are discussed. A systematic variation in the out-of-plane distortion (ruffling) of light element Group 14 and 15 porphyrin complexes has become apparent now that a significant number of structurally characterized examples are at hand.

As ²¹³Bi, a spontaneous alpha-emitting radioisotope, and ¹⁰B, a neutron-activated source of alpha particles, have been found to be potential tools in the treatment of cancer patients, a novel bismuth porphyrin, bearing both boron atoms and a strap with a hanging carboxylic group, was synthesized.

Organometallic porphyrins with a metal, metalloid or phosphorus fragment directly attached to their carbon framework emerged for the first time in 1976, and these macrocycles have been intensively investigated in the past decade. The present review summarises for the first time all reported examples as well as applications of these systems.

In this paper, we describe some observations from the attempted reaction of Br-BsubPc with phenol in DMF and DMAc. During these efforts, we found that Br-BsubPc reacts with the respective solvents to produce axially substituted formate-BsubPc and acetate-BsubPc. When no phenol is present the reaction proceeds to completion in a relatively short period of time. However, when phenol was present in DMF the reaction produced a mixture of formate-BsubPc, phenoxy-BsubPc, and HO-BsubPc. Similar results were found for the less-reactive Cl-BsubPc and MsO-BsubPc. Aside from these observations, it was found that simple heating in wet acetone of Br-BsubPc quantitatively produced HO-BsubPc after a facile workup. This method of producing HO-BsubPc removes the high temperatures, long reaction times, and harmful chemicals required in other synthetic methods. These results are relevant to anyone considering the reaction of BsubPcs in polar aprotic solvents.