The Li metal battery with ultrahigh-nickel cathode(LiNi_(x)M_(1-x)O_(2),M=Mn,Co,and x≥0.9)under high-voltage is regarded as one of the most promising approaches to fulfill the ambitious target of 400 Wh/kg.However,th...The Li metal battery with ultrahigh-nickel cathode(LiNi_(x)M_(1-x)O_(2),M=Mn,Co,and x≥0.9)under high-voltage is regarded as one of the most promising approaches to fulfill the ambitious target of 400 Wh/kg.However,the practical application is impeded by the instability of electrode/electrolyte interface and Ni-rich cathode itself.Herein we proposed an electron-defect electrolyte additive trimethyl borate(TMB)which is paired with the commercial carbonate electrolyte to construct highly conductive fluorine-and boron-rich cathode electrolyte interface(CEI)on LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)(NCM90)surface and solid electrolyte interphase(SEI)on lithium metal surface.The modified CEI effectively mitigates the structural transformation from layered to disordered rock-salt phase,and consequently alleviate the dissolution of transition metal ions(TMs)and its“cross-talk”effect,while the enhanced SEI enables stable lithium plating/striping and thus demonstrated good compatibility between electrolyte and lithium metal anode.As a result,the common electrolyte with 1 wt%TMB enables 4.7 V NCM90/Li cell cycle stably over 100 cycles with 70%capacity retention.This work highlights the significance of the electron-defect boron compounds for designing desirable interfacial chemistries to achieve high performance NCM90/Li battery under high voltage operation.展开更多
Lead-free low melting glasses,ZnO-CuO-Bi_(2)O_(3)-B_(2)O_(3)-SiO_(2)system,with fixed contents of 15 mol%CuO and 20 mol%Bi_(2)O_(3),were prepared by using melt cooling method.Structure and thermal properties of the gl...Lead-free low melting glasses,ZnO-CuO-Bi_(2)O_(3)-B_(2)O_(3)-SiO_(2)system,with fixed contents of 15 mol%CuO and 20 mol%Bi_(2)O_(3),were prepared by using melt cooling method.Structure and thermal properties of the glasses were studied by using X-ray diffractometer(XRD),infrared spectrometer(FIT-IR),thermal dilatometer and differential thermal analyzer(DTA).Chemical durability of the glasses was studied by using dissolution rate method.Wettability of glasses on substrate was tested by using button sintering experiment.It is found that alkaline resistance of the glass solders is lower than that of plate glass and the water resistance is comparable with that of plate glass.The sealing temperatures are Ts=445-490℃,while the average thermal expansion coefficient from room temperature to 300℃is in the range of(65-82)×10^(−7)℃^(−1).At sealing temperature,the glass solders have good wettability on plate glass or alumina substrate.They are not crystallized even sintered at the sealing temperature for 30 min.The solder glasses are suitable for sealing plate glass,alumina and other inorganic non-metallic materials.展开更多
Cd-rich portion of the pseudo-binary system Cd3B2O6-Zn3B2O6 was investigated. A new cadmium zinc borate, Cd2.42Zn0.58B2O6, was synthesized successfully by a traditional solid-state reaction method. The compound crysta...Cd-rich portion of the pseudo-binary system Cd3B2O6-Zn3B2O6 was investigated. A new cadmium zinc borate, Cd2.42Zn0.58B2O6, was synthesized successfully by a traditional solid-state reaction method. The compound crystallizes in the monoclinic space group C2/c with a = 17.3048, b = 8.4356, c = 10.2962 A^°, β = 93.157°, V = 1500.7(2) A^°3, Dc = 5.683 g/cm^3, F(000) = 2301, Z = 24, R = 0.0351 and wR = 0.0741. In its structure, BO3 triangle, CdO6 and CdO5 (or ZnO5) polyhedra are joined together by sharing bridging O atoms to form an intricate three-dimensional framework. A comparison of the structures of Cd2.42Zn0.58B2O6, α-Cd3B2O6 and β-Cd3B2O6 is presented. The IR spectrum confirms the presence of BO3 unit. The UV cut-off wavelength of Cd2.42Zn0.58B2O6 is 313 nm. The differential thermal analysis (DTA) suggests that Cd2.42Zn0.58B2O6 is an incongruent melting compound.展开更多
The^(10)boron neutron-capture therapy(BNCT)is an emerging antitumoral method that shows increasing biomedical interest.BNCT is based on the selective accumulation of the^(10)boron isotope within the tumor,which is the...The^(10)boron neutron-capture therapy(BNCT)is an emerging antitumoral method that shows increasing biomedical interest.BNCT is based on the selective accumulation of the^(10)boron isotope within the tumor,which is then irradiated with low-energy thermal neutrons,generating nuclear fission that produces 7lithium,4helium,andγrays.Simple catechol-borate esters have been rather overlooked as precursors of melanin biosynthesis,and therefore,a proof-of-concept approach for using dopamine-borate(DABO)as a suitable boron-containing candidate for potential BNCT is presented here.DABO can spontaneously oxidize and autopolymerize in vitro,giving a soluble,eumelaninlike brown-black poly-DABO product.Melanotic melanoma cell cultures treated with 1 mM DABO for 24 and 48 h were viable and showed no signs of damage or cell death.The stability and possible trans-esterification of DABO is shortly discussed.Chemical calculations and quantitative structure-activity relationships(QSAR)analysis of DABO and the BNCT agent BPA indicated that they should be cell permeant and accumulate within lysosomes and melanosomes.Molecular modeling allows visualization of both the DABO precursor and the structure of a borate derivative of the proposed catechol-porphycene model for eumelanin,showing interesting features from molecular orbital calculations.The main difference between DABO and other agents,such as BPA,is that it is not a boronic acid nor a boron cluster.This simple catechol-borate ester(protected from oxidation and blackening)could be administrated to living cells and organisms,in which biosynthesis of boron-melanin in melanoma melanocytes can lead to improved BNCT.展开更多
The Sichuan Basin,with an area of about 20×104 km2,is situated at 102.5°~110°E and 27.67°~32.67°N.The underground brine resources in Sichuan basin are a type of comprehensive liquid mineral re...The Sichuan Basin,with an area of about 20×104 km2,is situated at 102.5°~110°E and 27.67°~32.67°N.The underground brine resources in Sichuan basin are a type of comprehensive liquid mineral resource.Pingluo展开更多
1 Introduction A salt lake is a naturally occurring complex body of water and salt interaction.More than 700 salt lakes are widely distributed in the area of the Qinghai-Tibet Plateau.Most of the salt lakes are famous...1 Introduction A salt lake is a naturally occurring complex body of water and salt interaction.More than 700 salt lakes are widely distributed in the area of the Qinghai-Tibet Plateau.Most of the salt lakes are famous for their abundance of lithium,potassium,magnesium,and boron resources.It is展开更多
Oleic acid (denoted as OA) surface-caped lanthanum borate nanorods, abbreviated as OA/LaBO3·H2O, were prepared via hydrothermal method. The microstructures of the as-prepared OA/LaBO3·H2O nanorods were chara...Oleic acid (denoted as OA) surface-caped lanthanum borate nanorods, abbreviated as OA/LaBO3·H2O, were prepared via hydrothermal method. The microstructures of the as-prepared OA/LaBO3·H2O nanorods were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The friction and wear properties of OA/LaBO3·H2O nanorods in rapeseed oil were evaluated with a four-ball tribo-tester. The results show that the as-prepared OA/LaBO3·H2O nanorods are hydrophobic and display nanorods morphology with uniform diameter of about 50 nm and length of up to 500 nm. In the meantime, OA/LaBO3·H2O nanorods can obviously improve the anti-wear and friction-reducing capacities of rapeseed oil, and the optimal anti-wear and friction-reducing properties of rapeseed oil were obtained at an OA/LaBO3·H2O content of 1% (mass fraction).展开更多
The effect of interface reaction on the fractal dimensions of fracture surface in aluminum borate whisker-reinforced aluminum alloy 6061 composite was investigated. The composite was fabricated by squeeze-casting tech...The effect of interface reaction on the fractal dimensions of fracture surface in aluminum borate whisker-reinforced aluminum alloy 6061 composite was investigated. The composite was fabricated by squeeze-casting technique. The fracture surfaces created in tensile test were measured by vertical sectioning method. Fractal phenomena were found in two plots, in which the measuring units were from 3 to 15 μm and 1 to 5 μm, respectively. The relation was established between the tensile properties and fractal dimension with measuring units of 3-15 μm. The results show that the ultimate tensile strength increases while the fracture surface roughness increases with fractal dimension increasing due to the change in fracture mode depending on the degree of interface reaction status induced by heat treatment. But when the measuring units are 1-5 μm, fractal dimension does not change with heat treatment.展开更多
According to the compositions of the underground gasfield brines in the west of Sichuan Basin,the phase equilibria in the ternary systems KBr-K2B4O7-H2O and KCl-K2B4O7-H2O at 373 K were studied using the isothermal di...According to the compositions of the underground gasfield brines in the west of Sichuan Basin,the phase equilibria in the ternary systems KBr-K2B4O7-H2O and KCl-K2B4O7-H2O at 373 K were studied using the isothermal dissolution equilibrium method.The solubilities of salts and the densities of saturated solutions in these ternary systems were determined.Using the experimental data,phase diagrams and density-composition diagrams were constructed.The two phase diagrams were simple co-saturation type,each having an invariant point,two univariant curves and two crystallization regions.The equilibrium solid phases in the ternary system KBr-K2B4O7-H2O are potassium bromide (KBr) and potassium tetraborate tetrahydrate (K2B4O7·4H2O),and those in the ternary system KCl-K2B4O7-H2O are potassium chloride (KCl) and potassium tetraborate tetrahydrate (K2B4O7·4H2O).Comparisons of the phase diagrams of the two systems at different temperatures show that there is no change in the crystallization phases,but there are changes in the size of the crystallization regions.As temperature increases,the solubility of K2B4O7·4H2O increases rapidly,so the crystallization field of K2B4O7·4H2O becomes smaller.展开更多
The microstructural features and the consequent mechanical properties were characterized in aluminium borate whisker(ABOw)(5, 10 and 15 wt.%) reinforced commercially-pure aluminium composites fabricated by conventiona...The microstructural features and the consequent mechanical properties were characterized in aluminium borate whisker(ABOw)(5, 10 and 15 wt.%) reinforced commercially-pure aluminium composites fabricated by conventional powder metallurgy technique. The aluminium powder and the whisker were effectively blended by a semi-powder metallurgy method. The blended powder mixtures were cold compacted and sintered at 600 ℃. The sintered composites were characterized for microstructural features by optical microscopy(OM), scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS), transmission electron microscopy(TEM) and X-ray diffraction(XRD) analysis. Porosity in the composites with variation in ABOw contents was determined. The effect of variation in content of ABOw on mechanical properties, viz. hardness, bending strength and compressive strength of the composites was evaluated. The dry sliding wear behaviour was evaluated at varying sliding distance at constant loads. Maximum flexural strength of 172 MPa and compressive strength of 324 MPa with improved hardness around HV 40.2 are obtained in composite with 10 wt.% ABOw. Further increase in ABOw content deteriorates the properties. A substantial increase in wear resistance is also observed with 10 wt.% ABOw. The excellent combination of mechanical properties of Al-10 wt.%ABOw composites is attributed to good interfacial bonds, less porosity and uniformity in the microstructure.展开更多
Nanometer crystal samarium borate with a particle size of 20~40?nm was prepared using replacing solvent drying technique. The wear resistance and load carrying capacity of 500SN base oil could be improved and the fri...Nanometer crystal samarium borate with a particle size of 20~40?nm was prepared using replacing solvent drying technique. The wear resistance and load carrying capacity of 500SN base oil could be improved and the friction coefficient could be decreased by the addition of nanometer samarium borate. But the dosage of samarium borate nanoparticles had to be controlled at a relatively low level, a higher concentration of nanoparticles was not of beneficial to the tribological performance of the oil. The optimal dosage of nanometer samarium borate is 1.0%. Tribochemical reactions took place in the tribological process, which resulted in the formation of deposition products including diboron trioxide and disamarium trioxide. Fe 2B and FeB were also found on the wear scar. The improvement of tribological properties of the oil comes from the formation of deposition layer and permeating layer. [展开更多
A novel ternary borate, sodium strontium pentaborate, NaSrB5O9, has been prepared by solid-state reaction below 800 ℃. The single-crystal X-ray structural analysis showed that NaSrB5O9 crystallizes in monoclinic, spa...A novel ternary borate, sodium strontium pentaborate, NaSrB5O9, has been prepared by solid-state reaction below 800 ℃. The single-crystal X-ray structural analysis showed that NaSrB5O9 crystallizes in monoclinic, space group P21/c with a = 6.499(2), b = 13.979(3), c = 8.045(2)A, β = 106.92(2)°, V = 699.2(3)A^3, Z = 4, Mr = 308.66, Dc = 2.932 g/cm^3, μ = 7.804 mm^-1, F(000) = 584, R = 0.0264 and wR = 0.0621 for 2426 observed reflections and 146 variables. NaSrB5O9 is a layered compound containing double ring B5O11 building units composed of two BO4 tetrahedra and three BO3 triangles. Each B5O11 unit is connected to four other equivalent units through exocyclic oxygen atoms to form a two-dimensional ∞^2 [B5O9]^3- layer. Symmetry-center related layers are stacked along the b axis and held together by Na^+ and Sr^2+ cations via electrostatic interactions.展开更多
The structure of LiSrY2(BO3)3 has been solved by single-crystal X-ray diffraction analysis at 298 and 113 K on different diffractometers.It crystallizes in trigonal with space group P-3m1(No.164).The cell paramete...The structure of LiSrY2(BO3)3 has been solved by single-crystal X-ray diffraction analysis at 298 and 113 K on different diffractometers.It crystallizes in trigonal with space group P-3m1(No.164).The cell parameters at room temperature are as follows:a = 10.3345(9),c = 6.4049(11) ,V = 592.41(13) 3,Z = 3,Mr = 448.81,F(000) = 618,μ = 21.327 mm-1 and Dc = 3.774 g/cm3.The crystal structure consists of gear-like [BY6O33] groups which are linked together by corner-sharing to form a two-dimensional layer parallel to the ab plane.These layers are connected one after another by sharing oxygen atoms with B(2) atoms along the c direction to construct a three-dimensional framework.Li and Sr atoms just occupy the cavities formed by oxygen atoms.In addition,the vibrational spectroscopy of LiSrY2(BO3)3 and photoluminescence properties of the Eu3+ doped LiSrY2(BO3)3 were also studied.展开更多
The complexation reaction between borate ions and phenol-formaldehyde resol resin in aqueous solution was studied by pH measurement, small model molecules and infrared spectroscopy. The results show that the complexat...The complexation reaction between borate ions and phenol-formaldehyde resol resin in aqueous solution was studied by pH measurement, small model molecules and infrared spectroscopy. The results show that the complexation can proceed completely and rapidly at room temperature. Borate ion attacks phenol hydroxyl groups and adjacent position hydroxymethyl groups on the phenol ring of the resin, and forms the coordinate bond between boron atom in borate ion and oxygen atom in the hydroxyl groups. The complexation is a quantitative reaction. The complex is a six member ring containing two oxygens and one boron. The complexation can release hydrogen ions resulting in the decreasing pH in the resin solution.展开更多
Dy^3+-doped borate glasses (LBLB) with high effective visible fluorescence emission were synthesized. The absorption spectrum and fluorescence spectrum of this glass were measured and analyzed. By using J-O theory,...Dy^3+-doped borate glasses (LBLB) with high effective visible fluorescence emission were synthesized. The absorption spectrum and fluorescence spectrum of this glass were measured and analyzed. By using J-O theory, the oscillator strengths for some absorption transitions were calculated according to the absorption spectra. The intensity parameters Ω1 (t = 2, 4, 6) of Dy^3+ were determined by using a least-squares fitting approach, and the values are 4.04 × 10^-20, 1.30 × 10^-20 and 1.82 × 10^-20 cm, respectively. The root-mean-square deviation δrma was calculated. Under UV light excitation, Dy^3+-doped borate glasses (LBLB) emit intense yellowish white lights. The excitation spectrum indicates that argon laser is the effective excitation source in Dy^3+-doped LBLB glasses展开更多
Copper coating was deposited on the surface of aluminum borate whisker by an electroless plating method.This method was used to modify the interfacial property of squeeze-casting aluminum borate whisker reinforced 606...Copper coating was deposited on the surface of aluminum borate whisker by an electroless plating method.This method was used to modify the interfacial property of squeeze-casting aluminum borate whisker reinforced 6061Al matrix composite.Interface observation indicates that the spinel reaction(MgAl2O4) is hindered by the copper coating,and the difference in interfacial reaction degree affects the tensile property and aging behavior of the composite.For the composite with less spinel reaction(MgAl2O4),its peak-aging process are postponed due to less depletion of magnesium.On the fracture surface of copper-coated composite dimples and fractures of whiskers are more,but on the fracture surface of uncoated composite pull-out of whiskers are more than that on the coated one.In uncoated composite the fracture generally originates from the near-interface-region.展开更多
Tribological properties of 150SN mineral oil and lubricating oils containing triethanolamine borate(TBE)with and without electromagnetic field impact were evaluated on a modified four-ball tribo-tester.The characteris...Tribological properties of 150SN mineral oil and lubricating oils containing triethanolamine borate(TBE)with and without electromagnetic field impact were evaluated on a modified four-ball tribo-tester.The characteristics of the worn surfaces were studied by scanning electronic microscopy(SEM),energy dispersive spectrometry(EDS)and X-ray photoelectron spectroscopy(XPS).Moreover,the tribological mechanisms are discussed from the viewpoint of physical effect and chemical effect.The results indicated that the friction coefficients and wear scar diameters(WSDs)lubricated by 150SN mineral oil under electromagnetic field were higher than those without electromagnetism impact.The WSDs of steel balls lubricated by TBE-doped oils under electromagnetic field were smaller than those obtained from non-electromagnetic field,but the friction coefficients were higher than those under non-electromagnetic field.A protective coating consists of wear particles could be formed on the frictional surface due to the physical effect of electromagnetic field on wear debris.The electromagnetic field could facilitate the interaction of elemental boron and nitrogen in TBE with metal interfaces,and contributes to forming tribo-chemical reaction film to reduce friction and wear.展开更多
A novel inorganic-organic hybrid borate,[Al2(fum)(H3BO3)(OH) 4]n·n(H3BO3) (1,H2fum = fumaric acid) ,has been synthesized and characterized by single-crystal X-ray diffraction,FTIR and elemental analysis...A novel inorganic-organic hybrid borate,[Al2(fum)(H3BO3)(OH) 4]n·n(H3BO3) (1,H2fum = fumaric acid) ,has been synthesized and characterized by single-crystal X-ray diffraction,FTIR and elemental analysis. Crystal data for compound 1: orthorhombic,space group Pnma,a = 14.108(3) ,b = 6.9412(14) ,c = 14.995(3)A,V = 1468.3(5)A^3,Z = 4,Mr = 359.72,Dc = 1.627 g/cm^3,μ = 0.254 mm^-1,F(000) = 736,the final R = 0.0492 and wR = 0.1650 with I 〉 2σ(I) . In compound 1,each Al^Ⅲ ion is coordinated by six oxygen atoms to adopt a distorted octahedral geometry. Both fumarate anion and the coordinated boric acid act as bidentate bridging ligands to link two neighboring Al^Ⅲ centers simultaneously. Each Al^Ⅲ ion is bridged by two μ2-hydroxyl ligands to construct an infinite wave-like [Al2(fum)(H3BO3)(OH) 4]n chain. These one-dimensional chains form hydrogen bonds with free boric acid molecules giving rise to a three-dimensional supramolecular network.展开更多
Two new nonmetal borates, [(C2H10N2)]2[B14O20(OH)6] 1 and [C8H22N4][B5O6(OH)4]2 2, have been synthesized under mild conditions and characterized by single-crystal X-ray diffraction, FTIR, elemental analysis and ...Two new nonmetal borates, [(C2H10N2)]2[B14O20(OH)6] 1 and [C8H22N4][B5O6(OH)4]2 2, have been synthesized under mild conditions and characterized by single-crystal X-ray diffraction, FTIR, elemental analysis and thermogravimetric analysis. Crystal data for compound 1: triclinic, space group P^-1, a = 8.4979(17), b = 8.8498(18), c = 10.065(2)A^°, α = 95.01(3), β = 96.99(3), γ = 116.82(3)°, V= 661.8(3)A^°^3, Z= 1, Mr = 697.63, Dc = 1.751 g/cm^3,μ = 0.163 mm^-1, F(000) = 356, the final R = 0.0372 and wR = 0.0968 (I 〉 2σ(I)); and those for compound 2: monoclinic, space group P21/c, a = 9.1867(18), b= 14.118(3), c = 10.334(2)A^°, β = 91.48(3)°, V = 1339.8(5)A^°^3, Z = 2, Mr = 610.46, Dc = 1.513 g/cm^3,μ = 0.135 mm^-1, F(000) = 632, the final R = 0.0350 and wR = 0.0912 (I 〉 2σ(I)). For both 1 and 2, the anionic units are interlinked via O-H…O hydrogen bonds to form a 3D supramolecular network, while the protonated cations are located in the free space of the inorganic borate framework and interact with the anions by electrostatic attraction and extensive N-H…O hydrogen bonds.展开更多
Tris(trimethylsilyl)borate(TMSB) has been intensively studied to improve the performances of lithiumion batteries. However, it is still an interesting issue needed to be resolved for the research on the Li^(+) solvati...Tris(trimethylsilyl)borate(TMSB) has been intensively studied to improve the performances of lithiumion batteries. However, it is still an interesting issue needed to be resolved for the research on the Li^(+) solvation structure affected by TMSB additive. Herein, the electrochemical tests, quantum chemistry calculations, potential-resolved in-situ electrochemical impedance spectroscopy measurements and surface analyses were used to explore the effects of Li^(+) solvation structure with TMSB additive on the formation of the cathode electrolyte interface(CEI) film in LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)/Li half cells. The results reveal that the TMSB additive is easy to complex with Li^(+) ion, thus weaken the intermolecular force between Li^(+) ions and ethylene carbonate solvent, which is benefit for the cycle performance. Besides, the changed Li^(+) solvation structure results in a thin and dense CEI film containing compounds with Si–O and B–O bonds which is favorable to the transfer of Li^(+) ions. As a result, the performances of the LNCM811/Li half cells are effectively improved. This research provides a new idea to construct a high-performance CEI film by adjusting the Li^(+) solvation structures.展开更多
基金financially supported by the National Key Research and Development Program of China(2022YFE0206300)the National Natural Science Foundation of China(U21A2081,22075074,22209047)+1 种基金the Natural Science Foundation of Hunan Province(2022JJ40140)the Hunan Provincial Department of Education Outstanding Youth Project(22B0864,23B0037)。
文摘The Li metal battery with ultrahigh-nickel cathode(LiNi_(x)M_(1-x)O_(2),M=Mn,Co,and x≥0.9)under high-voltage is regarded as one of the most promising approaches to fulfill the ambitious target of 400 Wh/kg.However,the practical application is impeded by the instability of electrode/electrolyte interface and Ni-rich cathode itself.Herein we proposed an electron-defect electrolyte additive trimethyl borate(TMB)which is paired with the commercial carbonate electrolyte to construct highly conductive fluorine-and boron-rich cathode electrolyte interface(CEI)on LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)(NCM90)surface and solid electrolyte interphase(SEI)on lithium metal surface.The modified CEI effectively mitigates the structural transformation from layered to disordered rock-salt phase,and consequently alleviate the dissolution of transition metal ions(TMs)and its“cross-talk”effect,while the enhanced SEI enables stable lithium plating/striping and thus demonstrated good compatibility between electrolyte and lithium metal anode.As a result,the common electrolyte with 1 wt%TMB enables 4.7 V NCM90/Li cell cycle stably over 100 cycles with 70%capacity retention.This work highlights the significance of the electron-defect boron compounds for designing desirable interfacial chemistries to achieve high performance NCM90/Li battery under high voltage operation.
基金National Natural Science Foundation of China(52172070)Jiangxi Provincial Natural Science Foundation(20242BAB25222)Jiangxi Provincial Graduate Innovation Special Fund Project(YC2022-S882 and YC2023-S808).
文摘Lead-free low melting glasses,ZnO-CuO-Bi_(2)O_(3)-B_(2)O_(3)-SiO_(2)system,with fixed contents of 15 mol%CuO and 20 mol%Bi_(2)O_(3),were prepared by using melt cooling method.Structure and thermal properties of the glasses were studied by using X-ray diffractometer(XRD),infrared spectrometer(FIT-IR),thermal dilatometer and differential thermal analyzer(DTA).Chemical durability of the glasses was studied by using dissolution rate method.Wettability of glasses on substrate was tested by using button sintering experiment.It is found that alkaline resistance of the glass solders is lower than that of plate glass and the water resistance is comparable with that of plate glass.The sealing temperatures are Ts=445-490℃,while the average thermal expansion coefficient from room temperature to 300℃is in the range of(65-82)×10^(−7)℃^(−1).At sealing temperature,the glass solders have good wettability on plate glass or alumina substrate.They are not crystallized even sintered at the sealing temperature for 30 min.The solder glasses are suitable for sealing plate glass,alumina and other inorganic non-metallic materials.
基金supported by the Special Foundation for Young Scientists of Beijing(No.2014000020124G009)
文摘Cd-rich portion of the pseudo-binary system Cd3B2O6-Zn3B2O6 was investigated. A new cadmium zinc borate, Cd2.42Zn0.58B2O6, was synthesized successfully by a traditional solid-state reaction method. The compound crystallizes in the monoclinic space group C2/c with a = 17.3048, b = 8.4356, c = 10.2962 A^°, β = 93.157°, V = 1500.7(2) A^°3, Dc = 5.683 g/cm^3, F(000) = 2301, Z = 24, R = 0.0351 and wR = 0.0741. In its structure, BO3 triangle, CdO6 and CdO5 (or ZnO5) polyhedra are joined together by sharing bridging O atoms to form an intricate three-dimensional framework. A comparison of the structures of Cd2.42Zn0.58B2O6, α-Cd3B2O6 and β-Cd3B2O6 is presented. The IR spectrum confirms the presence of BO3 unit. The UV cut-off wavelength of Cd2.42Zn0.58B2O6 is 313 nm. The differential thermal analysis (DTA) suggests that Cd2.42Zn0.58B2O6 is an incongruent melting compound.
文摘The^(10)boron neutron-capture therapy(BNCT)is an emerging antitumoral method that shows increasing biomedical interest.BNCT is based on the selective accumulation of the^(10)boron isotope within the tumor,which is then irradiated with low-energy thermal neutrons,generating nuclear fission that produces 7lithium,4helium,andγrays.Simple catechol-borate esters have been rather overlooked as precursors of melanin biosynthesis,and therefore,a proof-of-concept approach for using dopamine-borate(DABO)as a suitable boron-containing candidate for potential BNCT is presented here.DABO can spontaneously oxidize and autopolymerize in vitro,giving a soluble,eumelaninlike brown-black poly-DABO product.Melanotic melanoma cell cultures treated with 1 mM DABO for 24 and 48 h were viable and showed no signs of damage or cell death.The stability and possible trans-esterification of DABO is shortly discussed.Chemical calculations and quantitative structure-activity relationships(QSAR)analysis of DABO and the BNCT agent BPA indicated that they should be cell permeant and accumulate within lysosomes and melanosomes.Molecular modeling allows visualization of both the DABO precursor and the structure of a borate derivative of the proposed catechol-porphycene model for eumelanin,showing interesting features from molecular orbital calculations.The main difference between DABO and other agents,such as BPA,is that it is not a boronic acid nor a boron cluster.This simple catechol-borate ester(protected from oxidation and blackening)could be administrated to living cells and organisms,in which biosynthesis of boron-melanin in melanoma melanocytes can lead to improved BNCT.
基金Project supported by China National Nature Science Foundation (No. 41173071)the Research Fund for the Doctoral Program of Higher Education from the Ministry of Education of China (20115122110001)+1 种基金the Sichuan Youth Science and Technology Innovation Research Team Funding Scheme (2013TD0005)Innovation Team of CDUT(KYTD201405)
文摘The Sichuan Basin,with an area of about 20×104 km2,is situated at 102.5°~110°E and 27.67°~32.67°N.The underground brine resources in Sichuan basin are a type of comprehensive liquid mineral resource.Pingluo
基金Financial supports from the NSFCs (21106103, 21276194 and 21306136)the Specialized Research Funds for the Doctoral Program of Chinese Higher Education (20101208110003 and 20111208120003)+1 种基金the Natural Science Foundation of Tianjin (12JCQNJC03400)the Senior Professor Program for TUST (20100405)
文摘1 Introduction A salt lake is a naturally occurring complex body of water and salt interaction.More than 700 salt lakes are widely distributed in the area of the Qinghai-Tibet Plateau.Most of the salt lakes are famous for their abundance of lithium,potassium,magnesium,and boron resources.It is
基金Project(50975282)supported by the National Natural Science Foundation of China
文摘Oleic acid (denoted as OA) surface-caped lanthanum borate nanorods, abbreviated as OA/LaBO3·H2O, were prepared via hydrothermal method. The microstructures of the as-prepared OA/LaBO3·H2O nanorods were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The friction and wear properties of OA/LaBO3·H2O nanorods in rapeseed oil were evaluated with a four-ball tribo-tester. The results show that the as-prepared OA/LaBO3·H2O nanorods are hydrophobic and display nanorods morphology with uniform diameter of about 50 nm and length of up to 500 nm. In the meantime, OA/LaBO3·H2O nanorods can obviously improve the anti-wear and friction-reducing capacities of rapeseed oil, and the optimal anti-wear and friction-reducing properties of rapeseed oil were obtained at an OA/LaBO3·H2O content of 1% (mass fraction).
基金Project (20070213042) supported by Specialized Research Fund for the Doctoral Program of Higher Education, China
文摘The effect of interface reaction on the fractal dimensions of fracture surface in aluminum borate whisker-reinforced aluminum alloy 6061 composite was investigated. The composite was fabricated by squeeze-casting technique. The fracture surfaces created in tensile test were measured by vertical sectioning method. Fractal phenomena were found in two plots, in which the measuring units were from 3 to 15 μm and 1 to 5 μm, respectively. The relation was established between the tensile properties and fractal dimension with measuring units of 3-15 μm. The results show that the ultimate tensile strength increases while the fracture surface roughness increases with fractal dimension increasing due to the change in fracture mode depending on the degree of interface reaction status induced by heat treatment. But when the measuring units are 1-5 μm, fractal dimension does not change with heat treatment.
基金supported by the Open Fund (PLC201204) of State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation (Chengdu University of Technology)the National Natural Science Foundation of China (Grant No. 41373062,40973047, 41172118)+1 种基金the Specialized Research Fund (20125122110015) for the Doctoral Program of Higher Education of Chinathe youth science and technology innovation team of Sichuan Province, China(2013TD0005)
文摘According to the compositions of the underground gasfield brines in the west of Sichuan Basin,the phase equilibria in the ternary systems KBr-K2B4O7-H2O and KCl-K2B4O7-H2O at 373 K were studied using the isothermal dissolution equilibrium method.The solubilities of salts and the densities of saturated solutions in these ternary systems were determined.Using the experimental data,phase diagrams and density-composition diagrams were constructed.The two phase diagrams were simple co-saturation type,each having an invariant point,two univariant curves and two crystallization regions.The equilibrium solid phases in the ternary system KBr-K2B4O7-H2O are potassium bromide (KBr) and potassium tetraborate tetrahydrate (K2B4O7·4H2O),and those in the ternary system KCl-K2B4O7-H2O are potassium chloride (KCl) and potassium tetraborate tetrahydrate (K2B4O7·4H2O).Comparisons of the phase diagrams of the two systems at different temperatures show that there is no change in the crystallization phases,but there are changes in the size of the crystallization regions.As temperature increases,the solubility of K2B4O7·4H2O increases rapidly,so the crystallization field of K2B4O7·4H2O becomes smaller.
基金support provided by the Central Instrument Facility Centre(CIFC)of IIT(BHU)the Department of Ceramic Engineering especially Advance Refractory Lab(ARL)of IIT(BHU)Varanasi。
文摘The microstructural features and the consequent mechanical properties were characterized in aluminium borate whisker(ABOw)(5, 10 and 15 wt.%) reinforced commercially-pure aluminium composites fabricated by conventional powder metallurgy technique. The aluminium powder and the whisker were effectively blended by a semi-powder metallurgy method. The blended powder mixtures were cold compacted and sintered at 600 ℃. The sintered composites were characterized for microstructural features by optical microscopy(OM), scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS), transmission electron microscopy(TEM) and X-ray diffraction(XRD) analysis. Porosity in the composites with variation in ABOw contents was determined. The effect of variation in content of ABOw on mechanical properties, viz. hardness, bending strength and compressive strength of the composites was evaluated. The dry sliding wear behaviour was evaluated at varying sliding distance at constant loads. Maximum flexural strength of 172 MPa and compressive strength of 324 MPa with improved hardness around HV 40.2 are obtained in composite with 10 wt.% ABOw. Further increase in ABOw content deteriorates the properties. A substantial increase in wear resistance is also observed with 10 wt.% ABOw. The excellent combination of mechanical properties of Al-10 wt.%ABOw composites is attributed to good interfacial bonds, less porosity and uniformity in the microstructure.
文摘Nanometer crystal samarium borate with a particle size of 20~40?nm was prepared using replacing solvent drying technique. The wear resistance and load carrying capacity of 500SN base oil could be improved and the friction coefficient could be decreased by the addition of nanometer samarium borate. But the dosage of samarium borate nanoparticles had to be controlled at a relatively low level, a higher concentration of nanoparticles was not of beneficial to the tribological performance of the oil. The optimal dosage of nanometer samarium borate is 1.0%. Tribochemical reactions took place in the tribological process, which resulted in the formation of deposition products including diboron trioxide and disamarium trioxide. Fe 2B and FeB were also found on the wear scar. The improvement of tribological properties of the oil comes from the formation of deposition layer and permeating layer. [
基金Supported by the Talent Training Funds of Beijing (20051D0501501)the Funding Project for Academic Human Resources Development in Institutions of Higher Learning under the Jurisdiction of Beijing Municipality, and the Natural Science Foundation of Beijing (No. 2073021)
文摘A novel ternary borate, sodium strontium pentaborate, NaSrB5O9, has been prepared by solid-state reaction below 800 ℃. The single-crystal X-ray structural analysis showed that NaSrB5O9 crystallizes in monoclinic, space group P21/c with a = 6.499(2), b = 13.979(3), c = 8.045(2)A, β = 106.92(2)°, V = 699.2(3)A^3, Z = 4, Mr = 308.66, Dc = 2.932 g/cm^3, μ = 7.804 mm^-1, F(000) = 584, R = 0.0264 and wR = 0.0621 for 2426 observed reflections and 146 variables. NaSrB5O9 is a layered compound containing double ring B5O11 building units composed of two BO4 tetrahedra and three BO3 triangles. Each B5O11 unit is connected to four other equivalent units through exocyclic oxygen atoms to form a two-dimensional ∞^2 [B5O9]^3- layer. Symmetry-center related layers are stacked along the b axis and held together by Na^+ and Sr^2+ cations via electrostatic interactions.
基金supported by the Major Research Project of Xi’an University of Arts and Science (No.zd200906)the Special Fund of Education Committee of Shaanxi Province (No.09JK743)
文摘The structure of LiSrY2(BO3)3 has been solved by single-crystal X-ray diffraction analysis at 298 and 113 K on different diffractometers.It crystallizes in trigonal with space group P-3m1(No.164).The cell parameters at room temperature are as follows:a = 10.3345(9),c = 6.4049(11) ,V = 592.41(13) 3,Z = 3,Mr = 448.81,F(000) = 618,μ = 21.327 mm-1 and Dc = 3.774 g/cm3.The crystal structure consists of gear-like [BY6O33] groups which are linked together by corner-sharing to form a two-dimensional layer parallel to the ab plane.These layers are connected one after another by sharing oxygen atoms with B(2) atoms along the c direction to construct a three-dimensional framework.Li and Sr atoms just occupy the cavities formed by oxygen atoms.In addition,the vibrational spectroscopy of LiSrY2(BO3)3 and photoluminescence properties of the Eu3+ doped LiSrY2(BO3)3 were also studied.
文摘The complexation reaction between borate ions and phenol-formaldehyde resol resin in aqueous solution was studied by pH measurement, small model molecules and infrared spectroscopy. The results show that the complexation can proceed completely and rapidly at room temperature. Borate ion attacks phenol hydroxyl groups and adjacent position hydroxymethyl groups on the phenol ring of the resin, and forms the coordinate bond between boron atom in borate ion and oxygen atom in the hydroxyl groups. The complexation is a quantitative reaction. The complex is a six member ring containing two oxygens and one boron. The complexation can release hydrogen ions resulting in the decreasing pH in the resin solution.
文摘Dy^3+-doped borate glasses (LBLB) with high effective visible fluorescence emission were synthesized. The absorption spectrum and fluorescence spectrum of this glass were measured and analyzed. By using J-O theory, the oscillator strengths for some absorption transitions were calculated according to the absorption spectra. The intensity parameters Ω1 (t = 2, 4, 6) of Dy^3+ were determined by using a least-squares fitting approach, and the values are 4.04 × 10^-20, 1.30 × 10^-20 and 1.82 × 10^-20 cm, respectively. The root-mean-square deviation δrma was calculated. Under UV light excitation, Dy^3+-doped borate glasses (LBLB) emit intense yellowish white lights. The excitation spectrum indicates that argon laser is the effective excitation source in Dy^3+-doped LBLB glasses
文摘Copper coating was deposited on the surface of aluminum borate whisker by an electroless plating method.This method was used to modify the interfacial property of squeeze-casting aluminum borate whisker reinforced 6061Al matrix composite.Interface observation indicates that the spinel reaction(MgAl2O4) is hindered by the copper coating,and the difference in interfacial reaction degree affects the tensile property and aging behavior of the composite.For the composite with less spinel reaction(MgAl2O4),its peak-aging process are postponed due to less depletion of magnesium.On the fracture surface of copper-coated composite dimples and fractures of whiskers are more,but on the fracture surface of uncoated composite pull-out of whiskers are more than that on the coated one.In uncoated composite the fracture generally originates from the near-interface-region.
基金financial support provided by the Basic Science and Frontier Technology Research Project of Chongqing (CSTC, 2017jcyjAX0058)
文摘Tribological properties of 150SN mineral oil and lubricating oils containing triethanolamine borate(TBE)with and without electromagnetic field impact were evaluated on a modified four-ball tribo-tester.The characteristics of the worn surfaces were studied by scanning electronic microscopy(SEM),energy dispersive spectrometry(EDS)and X-ray photoelectron spectroscopy(XPS).Moreover,the tribological mechanisms are discussed from the viewpoint of physical effect and chemical effect.The results indicated that the friction coefficients and wear scar diameters(WSDs)lubricated by 150SN mineral oil under electromagnetic field were higher than those without electromagnetism impact.The WSDs of steel balls lubricated by TBE-doped oils under electromagnetic field were smaller than those obtained from non-electromagnetic field,but the friction coefficients were higher than those under non-electromagnetic field.A protective coating consists of wear particles could be formed on the frictional surface due to the physical effect of electromagnetic field on wear debris.The electromagnetic field could facilitate the interaction of elemental boron and nitrogen in TBE with metal interfaces,and contributes to forming tribo-chemical reaction film to reduce friction and wear.
基金supported by the Ningbo Natural Science Foundation (2009A610052)the "Qianjiang Talent" Programs of Zhejiang Province (2009R10032)the K. C. Wang Magna Fund in Ningbo University
文摘A novel inorganic-organic hybrid borate,[Al2(fum)(H3BO3)(OH) 4]n·n(H3BO3) (1,H2fum = fumaric acid) ,has been synthesized and characterized by single-crystal X-ray diffraction,FTIR and elemental analysis. Crystal data for compound 1: orthorhombic,space group Pnma,a = 14.108(3) ,b = 6.9412(14) ,c = 14.995(3)A,V = 1468.3(5)A^3,Z = 4,Mr = 359.72,Dc = 1.627 g/cm^3,μ = 0.254 mm^-1,F(000) = 736,the final R = 0.0492 and wR = 0.1650 with I 〉 2σ(I) . In compound 1,each Al^Ⅲ ion is coordinated by six oxygen atoms to adopt a distorted octahedral geometry. Both fumarate anion and the coordinated boric acid act as bidentate bridging ligands to link two neighboring Al^Ⅲ centers simultaneously. Each Al^Ⅲ ion is bridged by two μ2-hydroxyl ligands to construct an infinite wave-like [Al2(fum)(H3BO3)(OH) 4]n chain. These one-dimensional chains form hydrogen bonds with free boric acid molecules giving rise to a three-dimensional supramolecular network.
基金supported by the Natural Science Foundation of Ningbo City (2007A610022) K. C. Wong Magna Fund in Ningbo University
文摘Two new nonmetal borates, [(C2H10N2)]2[B14O20(OH)6] 1 and [C8H22N4][B5O6(OH)4]2 2, have been synthesized under mild conditions and characterized by single-crystal X-ray diffraction, FTIR, elemental analysis and thermogravimetric analysis. Crystal data for compound 1: triclinic, space group P^-1, a = 8.4979(17), b = 8.8498(18), c = 10.065(2)A^°, α = 95.01(3), β = 96.99(3), γ = 116.82(3)°, V= 661.8(3)A^°^3, Z= 1, Mr = 697.63, Dc = 1.751 g/cm^3,μ = 0.163 mm^-1, F(000) = 356, the final R = 0.0372 and wR = 0.0968 (I 〉 2σ(I)); and those for compound 2: monoclinic, space group P21/c, a = 9.1867(18), b= 14.118(3), c = 10.334(2)A^°, β = 91.48(3)°, V = 1339.8(5)A^°^3, Z = 2, Mr = 610.46, Dc = 1.513 g/cm^3,μ = 0.135 mm^-1, F(000) = 632, the final R = 0.0350 and wR = 0.0912 (I 〉 2σ(I)). For both 1 and 2, the anionic units are interlinked via O-H…O hydrogen bonds to form a 3D supramolecular network, while the protonated cations are located in the free space of the inorganic borate framework and interact with the anions by electrostatic attraction and extensive N-H…O hydrogen bonds.
基金supported by the National Natural Science Foundation of China(51962019)the Natural Science Foundation of Gansu Province(20JR5RA469)+1 种基金the Education Department of Gansu Province:"Star of Innovation"Project for Outstanding Graduate Students(2021CXZX-455)the Lanzhou University of Technology Hongliu First-class Discipline Construction Program。
文摘Tris(trimethylsilyl)borate(TMSB) has been intensively studied to improve the performances of lithiumion batteries. However, it is still an interesting issue needed to be resolved for the research on the Li^(+) solvation structure affected by TMSB additive. Herein, the electrochemical tests, quantum chemistry calculations, potential-resolved in-situ electrochemical impedance spectroscopy measurements and surface analyses were used to explore the effects of Li^(+) solvation structure with TMSB additive on the formation of the cathode electrolyte interface(CEI) film in LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)/Li half cells. The results reveal that the TMSB additive is easy to complex with Li^(+) ion, thus weaken the intermolecular force between Li^(+) ions and ethylene carbonate solvent, which is benefit for the cycle performance. Besides, the changed Li^(+) solvation structure results in a thin and dense CEI film containing compounds with Si–O and B–O bonds which is favorable to the transfer of Li^(+) ions. As a result, the performances of the LNCM811/Li half cells are effectively improved. This research provides a new idea to construct a high-performance CEI film by adjusting the Li^(+) solvation structures.