Academic literature on the topic 'Boron-Nitrogen Systems'

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Journal articles on the topic "Boron-Nitrogen Systems"

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Tang, Chengchun, Yoshio Bando, Chunyi Zhi, and Dmitri Golberg. "Boron–oxygen luminescence centres in boron–nitrogen systems." Chemical Communications, no. 44 (2007): 4599. http://dx.doi.org/10.1039/b711807d.

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LU, ZHANG-HUI, and QIANG XU. "RECENT PROGRESS IN BORON- AND NITROGEN-BASED CHEMICAL HYDROGEN STORAGE." Functional Materials Letters 05, no. 01 (March 2012): 1230001. http://dx.doi.org/10.1142/s1793604712300010.

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Boron- and nitrogen-based chemical hydrogen storage materials, such as metal borohydrides, ammonia borane, hydrazine borane, metal-nitrogen-hydrogen systems, ammonia, and hydrazine, have been extensively investigated in the past years. A variety of methods have been developed to decrease the reaction temperature and enhance the reaction kinetics of these systems. This feature article is to serve as an up to date account of the recent progress in chemical hydrogen storage with the boron- and nitrogen-based materials.
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Ts, Otgontuul. "B(N) redor and B spin echo studies for structural charactreization of Si-B-N precursor ceramics." Физик сэтгүүл 18, no. 397 (March 15, 2022): 76–87. http://dx.doi.org/10.22353/physics.v18i397.811.

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A Solid-state NMR spectroscopy is employed for the structural characterization oj precursorderived Si-B-C-N ceramics. Particular emphasis is given to the structural composition of the BNCx phase which plays a key role for the unusual high temperature stability of these materials. In the present work nB('5N) REDOR and B spin echo experiments are presented for two /SN enriched precursor systems, made from substituted polysilazanes and polvsilvlcarbodiimides. which provide interatomic boron-boron and boron-nitrogen distances. The obtained results are compatible with the presence of layered structures as reported for hexagonal boron nitride [h-BJ. The derived boron-nitrogen and boron-boron distances, however, are larger than in h-BN, reflecting some layer distortions. The boron-boron distances are found to decrease with increasing pyrolysis temperature, whereas the boron-nitrogen distances remain practically unaltered at elevated pyrolysis temperatures. On the basis of the present results it is concluded that intercalated BN.and sp2-carbon layers most likely constitute the BNCX. phase. The graphite-like carbon layers are assumed to create some internal pressure, which in turn is responsible for the observed interatomic distance increase in the BN layers. However, other scenarios, like the direct incorporation of small sp1-carbon domains into the BN-sheets, cannot be ruled out completely. Further work along this line appears to be necessary to develop a comprehensive structural model for the BNCxphase in such quarternarv ceramic systems.
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Favaro, M., F. Carraro, M. Cattelan, L. Colazzo, C. Durante, M. Sambi, A. Gennaro, S. Agnoli, and G. Granozzi. "Multiple doping of graphene oxide foams and quantum dots: new switchable systems for oxygen reduction and water remediation." Journal of Materials Chemistry A 3, no. 27 (2015): 14334–47. http://dx.doi.org/10.1039/c5ta01561h.

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Mateti, Srikanth, Irin Sultana, Ying Chen, Manikantan Kota, and Md Mokhlesur Rahman. "Boron Nitride-Based Nanomaterials: Synthesis and Application in Rechargeable Batteries." Batteries 9, no. 7 (June 27, 2023): 344. http://dx.doi.org/10.3390/batteries9070344.

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Conventional boron nitride material is a resistant refractory compound of boron and nitrogen with various crystalline forms. The hexagonal form, which corresponds to graphite, is used as a lubricant and an additive to cosmetic products because of its higher stability and softness. Recently, various nanostructured boron nitride materials, including nanosheets, nanotubes, nanoparticles, and nanocomposites with diverse new properties, have been achieved through the development of advanced synthesis techniques as well as a deeper understanding of the properties and related applications. As nanostructured boron nitride materials exhibit high chemical, thermal and mechanical stability, the incorporation of nanostructured boron nitride materials into the key components (electrolytes, separators, and electrodes) of electrochemical systems can alleviate various inherent problems. This review article systematically summarizes the integration of nanostructured boron nitride into electrolytes, separators, and electrodes of lithium-ion, sodium-ion, and lithium-sulfur batteries. Various structures, synthesis methods, properties, and electrochemical performance of nanostructured boron nitride incorporated electrolytes, separators, and electrodes in rechargeable batteries are discussed. The challenges and possibilities for future application of boron nitride-based nanomaterials in electrochemical energy storage systems are also highlighted.
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Righetti, Timothy L. "Fate of Labeled Nitrogen, Zinc, and Boron in Fruit Orchard Systems." HortScience 32, no. 3 (June 1997): 556C—556. http://dx.doi.org/10.21273/hortsci.32.3.556c.

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Nitrogen, boron, and zinc are the major deficiencies encountered in Oregon tree fruit production. Much of our current management strategies are based on studies evaluating the uptake and plant mobility of labeled N, Zn, and B. Because mature trees differ from young plants, most of our experiments are conducted on fully bearing trees. Nitrogen strategies emphasize applying minimal amounts to avoid excess vigor and poor fruit quality. Our goal is to produce moderately vigorous trees with low fruit N, while still maintaining adequate tree reserves for early spring growth. Labeled 15N studies suggest that the later N is applied, the less is partitioned into leaves and fruit, with more N incorporated into storage tissues. Postharvest foliar applications of urea can also produce high bud N levels in combination with moderate vigor and low fruit N. Partitioning differences from various timings also result in different utilization efficiencies, especially if one considers N losses from pruning. Early N applications may have smaller efficiencies because pruning losses are greater. Although plant B is thought to be immobile, foliar-applied B is rapidly mobilized out of the leaf. Postharvest foliar B applications are an excellent way to ensure that buds have adequate B levels the following spring. Unlike N and B, Zn is not mobilized out of the leaf where it is applied. Sprays directly to young tissues in the spring are the only practical ways of increasing Zn levels.
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Zang, Chuan Yi, Lun Jian Chen, and Li Xue Chen. "HPHT Growth and IR Characterizaton of Large Diamond Crystals in FeNi-C-FeS Systems." Advanced Materials Research 339 (September 2011): 491–95. http://dx.doi.org/10.4028/www.scientific.net/amr.339.491.

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By temperature gradient method (TGM), with Invar alloy as solvent catalyst, FeS and boron as additives, large diamond crystals are grown under high pressure and high temperature (HPHT) of about 5.4GPa and 1550K. With the content of FeS increased, the colors of grown crystals would be changed from transparent yellow to opaque gray-black, and the quality of diamond crystals could also be destroyed markedly. When both boron and FeS co-doped, the negative effect of FeS on crystal quality could be eliminated somewhat. To a certain content of FeS, with the boron content increased, the crystal color would be changed from opaque gray-black to transparent yellow, and boron content needed is related directly to FeS content in growth systems. The nitrogen content in diamond lattice decreases greatly, with FeS content increased in the growth system, and a 1050cm-1 absorption peak in IR spectrum is also present in diamond crystals grown in FeNi-FeS-C system.
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Enyashin, A. N., Yu N. Makurin, and A. L. Ivanovskii. "Quantum chemical study of the electronic structure of new nanotubular systems: α-graphyne-like carbon, boron–nitrogen and boron–carbon–nitrogen nanotubes." Carbon 42, no. 10 (2004): 2081–89. http://dx.doi.org/10.1016/j.carbon.2004.04.014.

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Palmer, Michael H., and John A. Blair-Fish. "Quadrupole Coupling Assignments in Inorganic Periodic Systems by ab initio Calculation of Electric Field Gradients." Zeitschrift für Naturforschung A 49, no. 1-2 (February 1, 1994): 137–45. http://dx.doi.org/10.1515/zna-1994-1-222.

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Abstract Ab initio SCF calculations were performed in the unit cell environment, making use of the periodic behaviour to compute a wave-function for the bulk material. Electric field gradient (EFG) calcula­tions were performed on the resulting wave-functions, and these are compared with experimental quadrupole coupling parameters. Examples of inorganic molecular and ionic crystals (nitrogen, chlorine and lithium nitride) and minerals or partially covalent lattice structures (alumina, petalite, α-quartz, boron oxide, boron nitride and sulphur nitride) are described. The effects of the basis set in these calculations are considered, and the limitations imposed by the nature of the calculation are described.
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Hirai, Masato, Naoki Tanaka, Mika Sakai, and Shigehiro Yamaguchi. "Structurally Constrained Boron-, Nitrogen-, Silicon-, and Phosphorus-Centered Polycyclic π-Conjugated Systems." Chemical Reviews 119, no. 14 (March 12, 2019): 8291–331. http://dx.doi.org/10.1021/acs.chemrev.8b00637.

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Dissertations / Theses on the topic "Boron-Nitrogen Systems"

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Cui, Jian. "Synthesis and characterization of new boron-nitrogen and boron-nitrogen-phosphorus systems." [Fort Worth, Tex.] : Texas Christian University, 2009. http://etd.tcu.edu/etdfiles/available/etd-03162010-123538/unrestricted/Cui.pdf.

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Kurata, Ryohei. "Studies on Electronic Properties of Nitrogen-and Boron-Containing π-Electron Systems." Doctoral thesis, 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225623.

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京都大学
0048
新制・課程博士
博士(工学)
甲第20398号
工博第4335号
新制||工||1672(附属図書館)
京都大学大学院工学研究科分子工学専攻
(主査)教授 関 修平, 教授 今堀 博, 准教授 伊藤 彰浩, 教授 白川 昌宏
学位規則第4条第1項該当
Doctor of Philosophy (Engineering)
Kyoto University
DGAM
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Giustra, Zachary Xavier. "Studies of BN-Isosteres of Carbocyclic Systems." Thesis, Boston College, 2018. http://hdl.handle.net/2345/bc-ir:108092.

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Thesis advisor: Shih-Yuan Liu
The first three chapters of this dissertation elaborate on certain facets of the isosteric relationship between different types of boron-nitrogen-containing heterocycles and the corresponding all-carbon compounds. In this vein, Chapter 1 describes selective photoisomerization of aromatic 1,2-dihydro-1,2-azaborines to BN-analogues of bicyclo[2.2.0]hexa-2,5-diene (Dewar benzene). In one instance, the photoisomer product was further derivatized into a series of disubstituted cyclobutanes through manipulations of the boron functionality. Chapter 2 discloses a combined experimental/theoretical mechanistic investigation of preliminary hydrogen release from the amine borane unit in a pair of BN-cycloalkanes. In Chapter 3, the kinetics of complementary dehydrogenation of the alkyl units in a BN-cyclohexene derivative are compared with those of related six-membered carbocycles. Chapter 4 treats with the separate subject of enantioselective silylation of glycerol by a catalytic strategy centered around reversible covalent binding of substrate hydroxyl groups
Thesis (PhD) — Boston College, 2018
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
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Kukreja, Ratandeep. "Synthesis of Thin Films in Boron-Carbon-Nitrogen Ternary System by Microwave Plasma Enhanced Chemical Vapor Deposition." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1285688216.

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"Synthesis and Characterization of New Boron-Nitrogen and Boron-Nitrogen-Phosphorus Systems." Texas Christian University, 2010. http://etd.tcu.edu/etdfiles/available/etd-03162010-123538/.

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Nkambule, Sifiso Musa. "Computational study of random boron-carbon-nitrogen systems." Thesis, 2010. http://hdl.handle.net/10539/8487.

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Elastic properties, total formation energies and cell parameters of B-C structures are studied by molecular dynamics (MD) simulation. A well tested empirical Tersoff interatomic potentialfor simulation using a General Utility Lattice program (GULP). The results are compared with the available experimental results for Diamond and BC5. The work is extended to the study of B-C-N materials. We compare with available experimental results for BN and BC2N. The Bulk Modulus, Shear Modulus, Young’s Modulus and Elastic constants are obtained strongly implying hardness comparable to that of diamond. The Novel B-C and B-C-N material are proposed to be ultra-hard materials with different chemical and electrical properties from those of diamond and with potentially very useful application such as advanced abrasives, high temperature electronics and semiconductors.
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Book chapters on the topic "Boron-Nitrogen Systems"

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Bunting, R. K. "Boron-Nitrogen Systems." In Inorganic Reactions and Methods, 83–86. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470145326.ch47.

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Tomashik, Vasyl. "Boron – Carbon – Nitrogen." In Refractory metal systems, 444–73. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-88053-0_19.

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Tomashik, Vasyl´. "Boron – Nitrogen – Titanium." In Refractory metal systems, 83–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-02700-0_7.

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Tomashik, Vasyl. "Boron – Iron – Nitrogen." In Iron Systems, Part 1, 457–71. Berlin, Heidelberg: Springer Berlin Heidelberg, 2008. http://dx.doi.org/10.1007/978-3-540-69761-9_20.

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Bunting, R. K. "Interconversions in Boron-Nitrogen Systems." In Inorganic Reactions and Methods, 89. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470145326.ch51.

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Shih, Jheng-Hong, Jhao-Ying Wu, and Ming-Fa Lin. "Electronic and Optical Properties of Boron-/Carbon- and Nitrogen-Substituted Silicene Systems." In Diverse Quasiparticle Properties of Emerging Materials, 177–89. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003322573-8.

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Meller, Anton. "The System Boron-Nitrogen." In B Boron Compounds, 1–261. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-662-06141-1_1.

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Quesnel, Benoît, Christophe Scheffer, and Georges Beaudoin. "The Light Stable Isotope (Hydrogen, Boron, Carbon, Nitrogen, Oxygen, Silicon, Sulfur) Composition of Orogenic Gold Deposits." In Isotopes in Economic Geology, Metallogenesis and Exploration, 283–328. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-27897-6_10.

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AbstractOrogenic gold deposits formed in various terranes of most ages since the Paleoarchean and generally consist of quartz veins hosted in shear zones formed at the ductile brittle transition under greenschist to lower amphibolite metamorphic conditions. Vein mineralogy is dominated by quartz with various amounts of silicates, carbonates, phyllosilicates, borates, tungstates, sulfides, and oxides. The isotopic composition of these minerals and fluid inclusions has been investigated since the 1960s to constrain the characteristics of orogenic fluid systems involved in the formation of gold deposits worldwide. This review is based on 8580 stable isotope analyses, including δ18O, δD, δ13C, δ34S δ15N, δ11B, and δ30Si values, from 5478 samples from 558 orogenic gold deposits reported in the literature from 1960 to 2010. This contribution describes the variability of the light stable isotopic systems as function of the minerals, the age of the deposits, their regional setting, and their country rocks. The temperature of isotopic equilibrium of orogenic gold veins is estimated from mineral pairs for oxygen and sulfur isotopes. Based on these temperatures, and on fractionation between mineral and fluid components (H2O, CO2 and H2S), the isotopic composition of fluids is estimated to better constrain the main parameters shared by most of auriferous orogenic fluid systems. Orogenic gold deposits display similar isotopic features through time, suggesting that fluid conditions and sources leading to the formation of orogenic gold deposits did not change significantly from the Archean to the Cenozoic. No consistent secular variations of mineral isotope composition for oxygen (−8.1‰ ≤ δ18O ≤ 33‰, n = 4011), hydrogen (−187‰ ≤ δD ≤ −4‰, n = 246), carbon (−26.7‰ ≤ δ13C ≤ 12.3‰, n = 1179), boron (−21.6‰ ≤ δ11B ≤ 9‰, n = 119), and silicon (−0.5‰ ≤ δ30Si ≤ 0.8‰, n = 33) are documented. Only nitrogen (1.6‰ ≤ δ15N ≤ 23.7‰, n = 258) and sulfide sulfur from deposits hosted in sedimentary rocks (−27.2‰ ≤ δ34S ≤ 25‰, n = 717) display secular variations. For nitrogen, the change in composition is interpreted to record the variation of δ15N values of sediments devolatilized during metamorphism. For sulfur, secular variations reflect incorporation of local sedimentary sulfur of ultimate seawater origin. No significant variation of temperature of vein formation is documented for orogenic gold deposits of different ages. Quartz-silicate, quartz-carbonate and sulfide-sulfide mineral pairs display consistent temperatures of 360 ± 76 °C (1σ; n = 332), in agreement with the more common greenschist facies hostrocks and fluid inclusion microthermometry. Fluid sources for orogenic gold deposits are complex but the isotopic systems (hydrogen, boron, carbon, nitrogen, oxygen, sulfur) are most consistent with contributions from metamorphic fluids released by devolatilization of igneous, volcano-sedimentary and/or sedimentary rocks. The contribution of magmatic water exsolved from magma during crystallization is not a necessary component, even if permissible in specific cases. Isotopic data arrays can be interpreted as the result of fluid mixing between a high T (~550 °C)—high δ18O (~10‰)—low δD (~−60‰) deep-seated (metamorphic) fluid reservoir and a low T (~200 °C)—low δ18O (~2‰)—high δD (~0‰) upper crustal fluid reservoir in a number of orogenic gold deposits. The origin of the upper crustal fluid is most likely sea- or meteoric water filling the host rock porosity, with a long history of water–rock isotope exchange. Mixing of deep-seated and upper crustal fluids also explains the large variation of tourmaline δ11B values from orogenic gold veins. Regional spatial variations of oxygen and hydrogen isotope compositions of deep-seated fluid reservoirs are documented between orogenic gold districts. This is the case for the Val-d’Or (Abitibi), Coolgardie and Kalgoorlie (Yilgarn) where the oxygen isotope composition of the deep-seated fluid end-member is 4‰ lower compared to that from the Timmins, Larder Lake, and Kirkland Lake districts (Abitibi). However, both mixing trends converge towards a common, low δ18O upper crustal fluid end-member. Such variations cannot be related to fluid buffering at the site of deposition and suggest provinciality of the fluid source. The contribution of meteoric water is mainly recorded by fluid inclusions from Mesozoic and Cenozoic age deposits, but micas are not systematically in isotopic equilibrium with fluid inclusions trapped in quartz from the same vein. This suggests late involvement of meteoric water unrelated to deposit formation. Yet, a number of deposits with low δD mica may record infiltration of meteoric water in orogenic gold deposits. Isotope exchange between mineralizing fluid and country rocks is documented for oxygen, carbon, sulfur and silicon isotopes. Large variations (> 10‰) of sulfide δ34S values at the deposit scale are likely related to evolving redox conditions of the mineralizing fluid during reaction with country rocks. Deposits hosted in sedimentary rocks show a shift to higher δ18O values as a result of fluid/rock oxygen exchange with the regional sedimentary country rocks.
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"Al-B-N (Aluminium - Boron - Nitrogen)." In Light Metal Systems. Part 1, 56–66. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/10915943_8.

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"B-Li-N (Boron - Lithium - Nitrogen)." In Light Metal Systems. Part 4, 1–6. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/11008514_7.

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Conference papers on the topic "Boron-Nitrogen Systems"

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Yuko Hatanaka, Sadao Takeuchi, Koji Iwasaki, Hidenori Gamo, Kiyoharu Nakagawa, Toshihiro Ando, and Mikka Nishitani-Gamo. "Cathodoluminescence spectroscopic study of the boron-nitrogen co-doping diamond films." In 2008 International Conference on Control, Automation and Systems (ICCAS). IEEE, 2008. http://dx.doi.org/10.1109/iccas.2008.4694640.

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BAMANE, SWAPNIL, KRISHAN KANHAIYA, HENDRIK HEINZ, and GREGORY ODEGARD. "FORCE FIELD PARAMETERIZATION AND MOLECULAR DYNAMICS SIMULATION OF EPOXY INTERACTION WITH BORON NITRIDE NANOTUBE SURFACES." In Proceedings for the American Society for Composites-Thirty Seventh Technical Conference. Destech Publications, Inc., 2022. http://dx.doi.org/10.12783/asc37/36444.

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Wettability is a key phenomenon in understanding solid-liquid interface behavior in composite materials and is important in the manufacturing of boron nitride nanotube (BNNT)-based composite materials. Wettability is often quantified by calculating the contact angle values of liquid resin droplets on reinforcement surfaces. Determining contact angle values using experimental techniques for nanomaterials like BNNT is challenging and costly. Computational simulations with interface calculation capabilities offer an easier approach to solve this problem. In this study, a molecular dynamics framework is used to determine the contact angle values of various epoxy systems on the BNNT surface. The Interface Force-Field (IFF) was used for this study. Forcefield parameters were developed to describe the interaction of boron (B) atoms, nitrogen (N) atoms, and the pi electrons that dominate the out-of-plane behavior of two-dimensional B-N materials. A single layer BNNT surface was modelled as shown in “Figure 1”. For wetting simulations, the selection of resin system is based on a combination of EPON 862 and EPON 828 monomers with aromatic amine hardeners and aliphatic amine hardeners. The results are dependent on the chemical groups present in the resin system, temperature, and the charges on the atoms in the functional groups. The EPON 828 systems show overall better wettability than EPON 862 systems irrespective of choice of hardener.
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Klesnar, Helmuth, and Peter Rogl. "The ternary system uranium - boron - nitrogen." In Boron-rich solids. AIP, 1991. http://dx.doi.org/10.1063/1.40810.

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Ottens, Werner, Eberhard Roos, Hans Kockelmann, and Rolf Hahn. "Optimization of Stuffing Box Stem Sealings in Valves by Means of Surface Treatment and Coating." In ASME 2010 Pressure Vessels and Piping Division/K-PVP Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/pvp2010-25043.

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The optimization of the frictional behavior of valve stems in stuffing box sealing systems by means of stem surface treatment and coating is subject of a research project carried out at MPA Stuttgart. Low friction should lead to a high compression and densification of the packing already during assembly resulting in a reduced drop of packing stress with service time and improved tightness. Several surface treatment and coating technologies (Nitrogen and Boron Hardening, inductive coat, Si- and Me-DLC, AlTiN, Chromium-Nitride Multilayer, Tungsten-Carbide and Chromium-Carbide) were examined. Friction tests were carried out at 400 °C followed by leakage tests (160 bar, test fluid Nitrogen) on simulated stuffing box sealings with usual graphite packings and coated or surface treated stems in comparison to a “standard” stem without coating and surface treatment. These combined friction and leakage tests were accompanied by mechanical, technological and metallographical investigations. Visual inspection of the stems after the friction tests suggests a classification in 3 categories depending on the graphite adhesion to the stem surface. Some coatings caused a deterioration (increase of leakage rate) compared to the standard stem (without any coating or surface treatment). In the other cases the leakage rates were comparable to that of the standard stem. Most favorable behavior was observed for the stem with inductive coat. This technology can be seen as a repair technology for damaged stems.
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BHUSAL, SHUSIL, JONGHOON LEE, and AJIT K. ROY. "STRUCTURAL AND ELECTRONIC PROPERTIES OF BCN NANOFLAKES VIA GRAPH THEORY." In Thirty-sixth Technical Conference. Destech Publications, Inc., 2021. http://dx.doi.org/10.12783/asc36/35864.

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Boron-carbon-nitride (BCN), a ternary system, enables us to compose a wide variety of novel materials due to their unique mechanical, thermal, and electrical properties. We study two-dimensional structures called nanoflakes made of boron, carbon, and nitrogen atoms arranged in hexagonal lattice structures. The physical properties of these nanostructures, in general, are functions of the overall shape, stoichiometric ratio of boron carbon and nitrogen atoms, and their distribution. In this study, we utilize graph theory to randomly generate these structures, forming three different phases: hexagonal graphene, hexagonal boron nitride, and hexagonal BCN in various proportions. We perform density functional theory (DFT) simulations to obtain the optimized nanoflake structures and analyze the electronic structure. Our results have important implications for future studies of novel materials based on BCN nanoflakes and their experimental realizations.
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Gao, Ya-Dong, De-Dong He, Ke Gong, Guang-Yu Shi, Si-Yuan Chen, Chen-Xi Zhu, and Shi-Wei Jing. "Simulation Research on Explosives Detection System Based on D-D Sealed Neutron Generator." In ASME 2021 Power Conference. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/power2021-65387.

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Abstract A prompt gamma neutron activation analysis (PGNAA) system based on a deuterium-deuterium (D-D) sealed neutron generator was designed using the MOCA code for explosive detection. The system is mainly composed of four parts: D-D sealed neutron generator, moderator, shielding, and Lutetium Yttrium OxyorthoSilicate (LYSO) scintillation detectors. Polyethylene (PE) was selected as the moderator and the optimal thickness was 7cm. Lead, PE, and boron-containing polyethylene were used as shielding materials. In the optimized model, the LYSO detector is used to measure eighteen materials, such as wood, melamine, glucose, and nylon, and so on. Firstly, the nitrogen characteristic peak of 10.8 MeV was analyzed to determine whether the material contained nitrogen. Then, the ratio of characteristic peak counts of C/O and O/N were calculated to distinguish explosives from nitrogen containing materials. Finally, dinitrobenzene, nitroglycerin, TNT, and ammonium nitrate can be separated from nitrogenous substances by a discriminant algorithm. The final device can be used to detect the chemical composition of the threat substances, and the maximum dose rate of the system meets the limits of international protection standards.
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Reports on the topic "Boron-Nitrogen Systems"

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Besmann, T. M. Chemical vapor deposition in the silicon-carbon and boron-carbon-nitrogen systems. Office of Scientific and Technical Information (OSTI), November 1988. http://dx.doi.org/10.2172/6567811.

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Shaw, S. Y., G. M. Scheide, C. E. Davis, P. Mukherjee, and R. H. Neilson. Derivative Chemistry of the 1,3,2-Diazaboracyclohexane Ring System. Boron-Nitrogen Polymer Precursors. Fort Belvoir, VA: Defense Technical Information Center, January 1989. http://dx.doi.org/10.21236/ada204050.

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