Two new isostructural multi-metal beryllium borates, m^3 Li Na4Be4B10O24F(M = Sr(1), Cd(2)), have been synthesized by spontaneous crystallization. The structures were verified by single-crystal X-ray crystallogr...Two new isostructural multi-metal beryllium borates, m^3 Li Na4Be4B10O24F(M = Sr(1), Cd(2)), have been synthesized by spontaneous crystallization. The structures were verified by single-crystal X-ray crystallography. The compounds crystallize in the trigonal space group R 3, with a = b = 9.4645(1) A, c = 38.842(8) A, V = 3013.2(6) A3, Z = 6, F(000) = 2568, Dc = 3.005 g/cm^3, Mr = 908.9, R = 0.0327, w R = 0.0678, μ = 8.160 mm-1 for Sr3 Li Na4Be4B10O24F and a = b = 9.3019(8) A, c = 37.782(7) A, V = 2831.12(9) A3, Z = 6, F(000) = 2748, Dc = 3.459 g/cm^3, Mr = 983.24, R = 0.0158, w R = 0.0455, μ = 3.586 mm-1 for Cd3 Li Na4Be4B10O24F. The structures are characterized by an infinite two-dimensional [Be8B16O40F2]∞ double layer bridged by [B12O24] groups like a sandwich structure, while the cations reside in tunnels along different directions. UV-vis-IR diffuse reflectance spectroscopy demonstrates that their cut-off edges are below 200 nm. Thermal analysis shows that they melt incongruently and their melting points are around 740-770 ℃.展开更多
This paper is devoted to the rare-earth borates described by the general formula RM3(BO3)4, M = Al, Fe, and Cr, that have non-centrosymmetric trigonal slructure of the natural mineral huntite. It give a brief review...This paper is devoted to the rare-earth borates described by the general formula RM3(BO3)4, M = Al, Fe, and Cr, that have non-centrosymmetric trigonal slructure of the natural mineral huntite. It give a brief review of a spectroscopic research on YbAI3(BO3)4 (YbAB), on a large group of magnetic iron borates, and on NdCra(BO3)4.展开更多
1 Introduction Lithium and its compounds as national strategic resources are extensively used in national defense,industrial and agricultural production.As we know,the salt lakes in the western of China are famous for...1 Introduction Lithium and its compounds as national strategic resources are extensively used in national defense,industrial and agricultural production.As we know,the salt lakes in the western of China are famous for its high展开更多
Amounts of lithium-containing salt lake brine resources are widely distributed in the four provinces named Qinghai,Tibet,Inner Mongolia and Xinjiang province,especially the salt lakes in Qinghai-Tibet Plateau are abun...Amounts of lithium-containing salt lake brine resources are widely distributed in the four provinces named Qinghai,Tibet,Inner Mongolia and Xinjiang province,especially the salt lakes in Qinghai-Tibet Plateau are abundant of展开更多
It is well known that boron exists as polyborate anions in aqueous solution.Boron atom can coordinates to three or four oxygen atoms and borate can exist as not only the monomer but also the polymer.The polymerization
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
The antiwear and friction-reducing performances of sodium borate, potassium borate and lanthanum chloride in water were evaluated on a four-ball friction tester. The topographies, element distribution and chemical cha...The antiwear and friction-reducing performances of sodium borate, potassium borate and lanthanum chloride in water were evaluated on a four-ball friction tester. The topographies, element distribution and chemical characteristics of the worn surfaces were investigated by scanning electron microscope (SEM), energy dispersion of X-ray (EDX) and X-ray photoelectron spectroscope (XPS). The results indicated that sodium borate, potassium borate and lanthanum chloride increased extreme pressure, antiwear and friction-reducing capacities of water to a certain extent, of which potassium borate was the best candidate. Combination of lanthanum chloride with sodium borate and po- tassium borate respectively further improved antiwear and friction-reducing capacities. Scratches of worn surfaces lubricated with water containing borates and lanthanum chloride were less severe than those lubricated with water containing borates alone. A tribochemical film mainly composed of oxides of lanthanum, boron and iron reduced friction and wear for water lubricant formulated with both borates and lanthanum chloride.展开更多
Two new borate compounds, C4H10N2·B6O8(OH)2 and (NH3CH2CH2NH3)B5O8 (OH)2, have been solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, elemental analysis and...Two new borate compounds, C4H10N2·B6O8(OH)2 and (NH3CH2CH2NH3)B5O8 (OH)2, have been solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, elemental analysis and thermal analysis. Compound 1 crystallizes in the monoclinic system, space group P21/c, with a = 8.3318(17), b = 6.2118(12), c = 12.479(3) A, β = 108.96(3)°, V = 610.8(2) A^3, Mr = 313.02, Z = 2, 13,.= 1.702 g/cm^,/J = 0.150 mm^-1, F(000) = 320, R = 0.0387 and wR = 0.0924. Its layered structure is linked by infinite covalently coordinated neutral sheets with 3,20-membered window system, which are built up from alternative B6O8(OH)2 subunits donated by two piperzazine nitrogen donors. 2 crystallizes in monoclinic, space group Co, with a = 6.7207(13), b = 11.481 (2), c = 12.564(3)A,β = 95.25(3)°, V = 965.4(3) A^3, Mr = 261.18, Z = 4, Dc = 1.797 g/cm^3,/t = 0.164 mm^-1, F(000) = 536, R = 0.0396 and wR = 0.0752. Its oxoborate structure is generated from the sheets of 3,9-membered boron rings bonded diamine molecules through electrostatic and H-bonding interactions to form a two-dimensional layered network.展开更多
A benzotriazole-containing derivative was synthesized via the Mannich reaction.The structure was characterized by NMR spectroscopy.By utilizing computational chemistry and molecular simulation,the calculation and mapp...A benzotriazole-containing derivative was synthesized via the Mannich reaction.The structure was characterized by NMR spectroscopy.By utilizing computational chemistry and molecular simulation,the calculation and mapping of atomic charge and frontier molecular orbitals with complex structure of the borate were carried out.The acid number of BTBE(nitrogen-containing heterocyclic borate)was determined by the standard test method for acid number and the open observation method.The results showed that BTBE had a low initial acid number,because the acid number was changed only after 72 hours of hydrolysis,and it was negative after the hydrolysis reached 120 hours.The extreme-pressure friction resistance of BTBE and other four base oils was also determined.For 5 kinds of base oils,the friction experiment was carried out under a load of 30 kgf,and the BTBE showed a lowest wear scar diameter(0.365 mm)along with a highest maximum non-seizure load.The results showed that the EP friction resistance of BTBE was stronger than that of other four base oils under the same test conditions.The results of hydrolysis performance showed that the synthesized nitrogencontaining heterocyclic borate had a high resistance to hydrolysis,while demonstrating broad application prospects.展开更多
As a fundamental parameter of the optical crystals,birefringence plays a vital role in many optical applications,such as phase modulation,light splitting,and polarization,especially the phase matching process of the n...As a fundamental parameter of the optical crystals,birefringence plays a vital role in many optical applications,such as phase modulation,light splitting,and polarization,especially the phase matching process of the nonlinear optical crystals.The big birefringence not only benefits to the miniaturization of related devices,but also broadens the phase-matching wavelength range of nonlinear optical crystals.The design and synthesis of crystals with large birefringence becomes a hot research topic due to its more and more important applications in the optical modulation and laser technology fields.Herein,crystals with birefringence greater than 0.05 in the borate system are reviewed and classified according to different birefringent active groups,and the relationship between structure and properties is thoroughly explored.It is hoped that this review will provide a clear understanding of what kinds of building units and arrangements would have more opportunity to get adequate birefringence in borate systems and provide the statistical references to encourage the emergence of better crystal materials with large birefringence.展开更多
Aluminoborates(ABOs)show wide ultraviolet(UV)transmittance,and are one of the important types of UV and deep-UV nonlinear optical(NLO)materials.In recent years,the combination of AlO_(n)(n=4,5,6)polyhedra or their flu...Aluminoborates(ABOs)show wide ultraviolet(UV)transmittance,and are one of the important types of UV and deep-UV nonlinear optical(NLO)materials.In recent years,the combination of AlO_(n)(n=4,5,6)polyhedra or their fluorinated analogues with different polyborate anions leads to a rich variety of crystalline ABOs.In this review,we summarize the recent developments of UV and deep-UV NLO inorganic ABOs.These ABOs can be grouped into three types in terms of their compositions:(i)aluminum oxyborates,(ii)alkali/alkaline earth metal aluminoborates,and(iii)alkali/alkaline earth metal aluminoborate fluorides and fluoroaluminoborates.We discuss the synthesis,structural features,NLO properties,as well as related structure-performance relationships of these non-centrosymmetric ABOs.Finally,the future perspectives in this field are discussed.展开更多
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
Main observation and conclusion A new Rh(Ⅲ)-catalyzed direct C—H alkenylation of 2,3-unsubstitued indoles with alkenyl borates through C—H activation followed by transmetallation was described.This protocol provide...Main observation and conclusion A new Rh(Ⅲ)-catalyzed direct C—H alkenylation of 2,3-unsubstitued indoles with alkenyl borates through C—H activation followed by transmetallation was described.This protocol provides an efficient method for the synthesis of terminal C2-alkenylindoles under mild conditions,and also shows broad substrate scope and high functional group tolerance with respect to both components.Furthermore,the C2-alkenylated indole can be easily transformed into carboline derivative,which is an important polycyclic indole moiety in natural products and drug molecules.展开更多
Many kinds of borate can be obtained from salt-water solution of different compositions by artificial synthesis. However, borates have not yet been found in any evaporation process of natural B-bearing brines. M. G. V...Many kinds of borate can be obtained from salt-water solution of different compositions by artificial synthesis. However, borates have not yet been found in any evaporation process of natural B-bearing brines. M. G. Valyashko obtained 'eutecticborate' (MgO·B2O3·×H2O) from eutectic saturation brine (B2O3:1.2%) after 4-year reservation.展开更多
Lanthanide borates containing post transition metal main group elements, including Ga(Ⅲ), Ge(Ⅳ), Sb(Ⅴ) and Te(Ⅵ), as well as lanthanide salts of the oxyanions of lone pair cations, such as I(Ⅴ), Se(Ⅳ...Lanthanide borates containing post transition metal main group elements, including Ga(Ⅲ), Ge(Ⅳ), Sb(Ⅴ) and Te(Ⅵ), as well as lanthanide salts of the oxyanions of lone pair cations, such as I(Ⅴ), Se(Ⅳ) and Te(Ⅳ), were reviewed. The post transition metal main group elements in lanthanide borates adopt octahedral or tetrahedral geometry only. In the structure of lanthanide galloborates, only octahedral GaO6 was found while both octahedral GeO6 and tetrahedral GeO4 appeared in borogermanates. The fifth period elements Sb(Ⅴ) and Te(VI) prefer octahedral coordination geometry in lanthanide borates system. The second groups introduced to lanthanide oxyanions of lone pairs are mainly focused on do TM units, such as WO4 tetrahedron, VO5 square pyramid or MoO6 octahedron, and rigid tetrahedral groups like sulfate SO4, silica SiO4 or selenate SeO4 units. Divalent cations like Pb(Ⅱ) and magnetic ions of Cu(Ⅱ) or Mn(Ⅱ) were also included. The structure chemistry of lanthanide ions in these systems is rich. Coordination numbers from six to ten are discovered, yielding a wide range of coordination geometries including the pentagonal bipyramid, square antiprism, metabidiminished icosahedron, tricapped trigonal prism, capped triangular cupola, etc. The connectivity modes between the Ln polyhedra are miscellaneous, from 3D network, to 2D layer, 1D chain, tetramer, trimer, dimer and finally monomer. A number of compounds display NCS structures and strong SHG response, and many lanthanide compounds exhibit good luminescent properties in visible and IR region.展开更多
Two new belt-like borates Na_(4)[B_(9)O_(14)(OH)_(3)]·0.5H_(2)O(1)and Na_(5)[B_(9)O_(14)(OH)_(4)](2)have been synthesized under solvothermal conditions.Both compounds contain unprecedented B_(9)O_(16)(OH)_(n)^((n...Two new belt-like borates Na_(4)[B_(9)O_(14)(OH)_(3)]·0.5H_(2)O(1)and Na_(5)[B_(9)O_(14)(OH)_(4)](2)have been synthesized under solvothermal conditions.Both compounds contain unprecedented B_(9)O_(16)(OH)_(n)^((n+5))−[n=3(1),4(2)]clusters,which are constructed from four B_(3)O_(3) rings via three BO_(4) tetrahedra.Compound 1 exhibits a rare 1D belt with two types of 8-membered ring(MR)windows based on B_(9)O_(16)(OH)_(3)^(8−) clusters.Compound 2 features two different 1D belts built by different B_(9)O_(16)(OH)_(4)^(9−) units,which is first discovered in borate family.UV-Vis diffuse reflectance spectra reveal that compounds 1 and 2 have the cut-off edges below 190 nm,indicating that they may have potential application in deep UV(DUV)region.展开更多
The design and synthesis of new deep-ultraviolet(DUV)optical materials are important but challenging.It is well known that the polarizability anisotropy of linear[BO_(2)]^(−)is larger than those of[BO_(3)]^(3−)and[BO_...The design and synthesis of new deep-ultraviolet(DUV)optical materials are important but challenging.It is well known that the polarizability anisotropy of linear[BO_(2)]^(−)is larger than those of[BO_(3)]^(3−)and[BO_(4)]^(5−),which is the better choice for exploring excellent optical materials.Here,we search for such crystals in borate systems based on the unusual fundamental structural unit[BO_(2)]^(−).By combining the linear[BO_(2)]^(−)with the traditional triangular[BO_(3)]^(3−)and tetrahedral[BO_(4)]^(5−)units,a new mixed metal borate,Rb_(5)Ba_(2)(B_(10)O_(17))_(2)(BO_(2))was obtained via high-temperature solution method.It exhibits excellent optical properties including a DUV transmission window(188 nm)and suitable birefringence(0.06).It also has good thermal stability and its crystal plates can be prepared easily.Furthermore,the strategies of designing borates with[BO_(2)]^(−)units have been proposed from the transformation of crystal framework and the preparation method.展开更多
Two new alkaline metal borates containing 1D{B5}/{B6}oxoboron helical chains,namely Na0.5[B5O8(OH)2]0.5[B5O6(OH)2]0.5·0.5H3O(1)and NaKCs[B6O9(OH)3](2)were synthesized under solvothermal conditions.Compound 1 cont...Two new alkaline metal borates containing 1D{B5}/{B6}oxoboron helical chains,namely Na0.5[B5O8(OH)2]0.5[B5O6(OH)2]0.5·0.5H3O(1)and NaKCs[B6O9(OH)3](2)were synthesized under solvothermal conditions.Compound 1 contains the interesting alternative left-and right-handed helical{[B5O8(OH)2][B5O6(OH)2]}2-({B5}-1 and{B5}-2)1D chains and compound 2 possesses the similar[B6O11(OH)3]7-({B6})chains.Their 1D chains are further assembled into 2D layers and 3D supramolecular frameworks through O-H…O hydrogen bonds.In addition,the UV cutoff edge of compounds 1 and 2 is both below 190 nm.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
Both numerical and experimental studies of the stability and electronic properties of barium–sodium metaborate Ba_(2)Na_(3)(B_(3)O_(6))_(2)F(P63/m) at pressures up to 10 GPa have been carried out. Electronic-structur...Both numerical and experimental studies of the stability and electronic properties of barium–sodium metaborate Ba_(2)Na_(3)(B_(3)O_(6))_(2)F(P63/m) at pressures up to 10 GPa have been carried out. Electronic-structure calculations with HSE06 hybrid functional showed that Ba_(2)Na_(3)(B_(3)O_(6))_(2)F has an indirect band gap of 6.289 eV. A numerical study revealed the decomposition of Ba_(2)Na_(3)(B_(3)O_(6))_(2)F into the BaB_(2)O_(4),Na BO_(2), and NaF phases above 3.4 GPa at 300 K. Subsequent high-pressure high-temperature experiments performed using ‘Discoverer-1500’DIA-type apparatus at pressures of 3 and 6 GPa and temperature of 1173 K confirmed the stability of Ba_(2)Na_(3)(B_(3)O_(6))_(2)F at 3 GPa and its decomposition into BaB_(2)O_(4), NaBO_(2), and NaF at 6 GPa, which was verified by energy-dispersive X-ray analysis and Raman spectroscopy. The observed Raman bands of the Ba_(2)Na_(3)(B_(3)O_(6))_(2)F phase were assigned by comparing the experimental and calculated spectra. The experimental Raman spectra of decomposition reaction products obtained at 6 GPa suggest the origin of a new high-pressure modification of barium metaborate BaB_(2)O_(4).展开更多
基金supported by the National Natural Science Foundation of China(No.50972149,61138004,51402316)the National Instrumentation Program(No.2012YQ120048)
文摘Two new isostructural multi-metal beryllium borates, m^3 Li Na4Be4B10O24F(M = Sr(1), Cd(2)), have been synthesized by spontaneous crystallization. The structures were verified by single-crystal X-ray crystallography. The compounds crystallize in the trigonal space group R 3, with a = b = 9.4645(1) A, c = 38.842(8) A, V = 3013.2(6) A3, Z = 6, F(000) = 2568, Dc = 3.005 g/cm^3, Mr = 908.9, R = 0.0327, w R = 0.0678, μ = 8.160 mm-1 for Sr3 Li Na4Be4B10O24F and a = b = 9.3019(8) A, c = 37.782(7) A, V = 2831.12(9) A3, Z = 6, F(000) = 2748, Dc = 3.459 g/cm^3, Mr = 983.24, R = 0.0158, w R = 0.0455, μ = 3.586 mm-1 for Cd3 Li Na4Be4B10O24F. The structures are characterized by an infinite two-dimensional [Be8B16O40F2]∞ double layer bridged by [B12O24] groups like a sandwich structure, while the cations reside in tunnels along different directions. UV-vis-IR diffuse reflectance spectroscopy demonstrates that their cut-off edges are below 200 nm. Thermal analysis shows that they melt incongruently and their melting points are around 740-770 ℃.
基金supported in part by the Russian Foundation for Basic Research (07-02-01185)the Russian Academy of Sciences under thgrams for Basic Research
文摘This paper is devoted to the rare-earth borates described by the general formula RM3(BO3)4, M = Al, Fe, and Cr, that have non-centrosymmetric trigonal slructure of the natural mineral huntite. It give a brief review of a spectroscopic research on YbAI3(BO3)4 (YbAB), on a large group of magnetic iron borates, and on NdCra(BO3)4.
基金Financial supports from the NNSFCs (Grants 21276194 and 21306136)the Specialized Research Fund for the Doctoral Program of Chinese Higher Education (Grant 20101208110003)the Opening Funds of Tianjin Key Laboratory of Marine Resources and Chemistry for Tianjin University of Science and Technology (Grant 201206)
文摘1 Introduction Lithium and its compounds as national strategic resources are extensively used in national defense,industrial and agricultural production.As we know,the salt lakes in the western of China are famous for its high
基金Financial support from the State Surface Project of National Natural Science of China (21276194)the Specialized Research Fund for the Doctoral Program of Chinese Higher Education (20101208110003)the Key Pillar Program of Tianjin Municipal Science and Technology (11ZCKGX02800)
文摘Amounts of lithium-containing salt lake brine resources are widely distributed in the four provinces named Qinghai,Tibet,Inner Mongolia and Xinjiang province,especially the salt lakes in Qinghai-Tibet Plateau are abundant of
基金Financial supports from the NNSFCs (Grants 201276194 and 201306136)the Funds of Tianjin Key Laboratory of Marine Resources and Chemistry in TUST (Grants 201303 and 201206)the Natural Science Fund of TUST (Grant 20130112)
文摘It is well known that boron exists as polyborate anions in aqueous solution.Boron atom can coordinates to three or four oxygen atoms and borate can exist as not only the monomer but also the polymer.The polymerization
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the National Natural Science Foundation of China (50275147)Program for New Century Excellent Talents in Chinese University (NCET-04-1002)Program for Innovative Groups in Chongqing’s Higher Schools
文摘The antiwear and friction-reducing performances of sodium borate, potassium borate and lanthanum chloride in water were evaluated on a four-ball friction tester. The topographies, element distribution and chemical characteristics of the worn surfaces were investigated by scanning electron microscope (SEM), energy dispersion of X-ray (EDX) and X-ray photoelectron spectroscope (XPS). The results indicated that sodium borate, potassium borate and lanthanum chloride increased extreme pressure, antiwear and friction-reducing capacities of water to a certain extent, of which potassium borate was the best candidate. Combination of lanthanum chloride with sodium borate and po- tassium borate respectively further improved antiwear and friction-reducing capacities. Scratches of worn surfaces lubricated with water containing borates and lanthanum chloride were less severe than those lubricated with water containing borates alone. A tribochemical film mainly composed of oxides of lanthanum, boron and iron reduced friction and wear for water lubricant formulated with both borates and lanthanum chloride.
基金the Natural Science Foundation of Henan Province (0611021600, 0311050500)the Key Discipline Foundation of Zhoukou Normal University
文摘Two new borate compounds, C4H10N2·B6O8(OH)2 and (NH3CH2CH2NH3)B5O8 (OH)2, have been solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, elemental analysis and thermal analysis. Compound 1 crystallizes in the monoclinic system, space group P21/c, with a = 8.3318(17), b = 6.2118(12), c = 12.479(3) A, β = 108.96(3)°, V = 610.8(2) A^3, Mr = 313.02, Z = 2, 13,.= 1.702 g/cm^,/J = 0.150 mm^-1, F(000) = 320, R = 0.0387 and wR = 0.0924. Its layered structure is linked by infinite covalently coordinated neutral sheets with 3,20-membered window system, which are built up from alternative B6O8(OH)2 subunits donated by two piperzazine nitrogen donors. 2 crystallizes in monoclinic, space group Co, with a = 6.7207(13), b = 11.481 (2), c = 12.564(3)A,β = 95.25(3)°, V = 965.4(3) A^3, Mr = 261.18, Z = 4, Dc = 1.797 g/cm^3,/t = 0.164 mm^-1, F(000) = 536, R = 0.0396 and wR = 0.0752. Its oxoborate structure is generated from the sheets of 3,9-membered boron rings bonded diamine molecules through electrostatic and H-bonding interactions to form a two-dimensional layered network.
文摘A benzotriazole-containing derivative was synthesized via the Mannich reaction.The structure was characterized by NMR spectroscopy.By utilizing computational chemistry and molecular simulation,the calculation and mapping of atomic charge and frontier molecular orbitals with complex structure of the borate were carried out.The acid number of BTBE(nitrogen-containing heterocyclic borate)was determined by the standard test method for acid number and the open observation method.The results showed that BTBE had a low initial acid number,because the acid number was changed only after 72 hours of hydrolysis,and it was negative after the hydrolysis reached 120 hours.The extreme-pressure friction resistance of BTBE and other four base oils was also determined.For 5 kinds of base oils,the friction experiment was carried out under a load of 30 kgf,and the BTBE showed a lowest wear scar diameter(0.365 mm)along with a highest maximum non-seizure load.The results showed that the EP friction resistance of BTBE was stronger than that of other four base oils under the same test conditions.The results of hydrolysis performance showed that the synthesized nitrogencontaining heterocyclic borate had a high resistance to hydrolysis,while demonstrating broad application prospects.
基金supported by Shanghai Cooperation Organization Science and Technology Partnership Program(2020E01039)the Scientific Instrument Developing Project,CAS(YJKYYQ20210033)+3 种基金CAS Youth Interdisciplinary Team(JCTD-2021–18)the West Light Foundation of CAS(2021-XBQNXZ-004)the Outstanding Youth Science Fund Project of Natural Science Foundation of Xinjiang(2022D01E90)Key Training Object of Talent Project of Urumqi。
文摘As a fundamental parameter of the optical crystals,birefringence plays a vital role in many optical applications,such as phase modulation,light splitting,and polarization,especially the phase matching process of the nonlinear optical crystals.The big birefringence not only benefits to the miniaturization of related devices,but also broadens the phase-matching wavelength range of nonlinear optical crystals.The design and synthesis of crystals with large birefringence becomes a hot research topic due to its more and more important applications in the optical modulation and laser technology fields.Herein,crystals with birefringence greater than 0.05 in the borate system are reviewed and classified according to different birefringent active groups,and the relationship between structure and properties is thoroughly explored.It is hoped that this review will provide a clear understanding of what kinds of building units and arrangements would have more opportunity to get adequate birefringence in borate systems and provide the statistical references to encourage the emergence of better crystal materials with large birefringence.
基金supported by the National Natural Science Foundation of China(Grant 21975224).
文摘Aluminoborates(ABOs)show wide ultraviolet(UV)transmittance,and are one of the important types of UV and deep-UV nonlinear optical(NLO)materials.In recent years,the combination of AlO_(n)(n=4,5,6)polyhedra or their fluorinated analogues with different polyborate anions leads to a rich variety of crystalline ABOs.In this review,we summarize the recent developments of UV and deep-UV NLO inorganic ABOs.These ABOs can be grouped into three types in terms of their compositions:(i)aluminum oxyborates,(ii)alkali/alkaline earth metal aluminoborates,and(iii)alkali/alkaline earth metal aluminoborate fluorides and fluoroaluminoborates.We discuss the synthesis,structural features,NLO properties,as well as related structure-performance relationships of these non-centrosymmetric ABOs.Finally,the future perspectives in this field are discussed.
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We are grateful to the National Natural Science Foundation of China(No.21302064)the Natural Science Foundation of Hubei Province(No.2017CFB690).
文摘Main observation and conclusion A new Rh(Ⅲ)-catalyzed direct C—H alkenylation of 2,3-unsubstitued indoles with alkenyl borates through C—H activation followed by transmetallation was described.This protocol provides an efficient method for the synthesis of terminal C2-alkenylindoles under mild conditions,and also shows broad substrate scope and high functional group tolerance with respect to both components.Furthermore,the C2-alkenylated indole can be easily transformed into carboline derivative,which is an important polycyclic indole moiety in natural products and drug molecules.
文摘Many kinds of borate can be obtained from salt-water solution of different compositions by artificial synthesis. However, borates have not yet been found in any evaporation process of natural B-bearing brines. M. G. Valyashko obtained 'eutecticborate' (MgO·B2O3·×H2O) from eutectic saturation brine (B2O3:1.2%) after 4-year reservation.
基金This work was supported by the National Natural Science Foundation of China (Grants 21773244, 21373222, and 21231006), the CAS Youth Innovation Promotion Association, and the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant XDB20000000).
文摘Lanthanide borates containing post transition metal main group elements, including Ga(Ⅲ), Ge(Ⅳ), Sb(Ⅴ) and Te(Ⅵ), as well as lanthanide salts of the oxyanions of lone pair cations, such as I(Ⅴ), Se(Ⅳ) and Te(Ⅳ), were reviewed. The post transition metal main group elements in lanthanide borates adopt octahedral or tetrahedral geometry only. In the structure of lanthanide galloborates, only octahedral GaO6 was found while both octahedral GeO6 and tetrahedral GeO4 appeared in borogermanates. The fifth period elements Sb(Ⅴ) and Te(VI) prefer octahedral coordination geometry in lanthanide borates system. The second groups introduced to lanthanide oxyanions of lone pairs are mainly focused on do TM units, such as WO4 tetrahedron, VO5 square pyramid or MoO6 octahedron, and rigid tetrahedral groups like sulfate SO4, silica SiO4 or selenate SeO4 units. Divalent cations like Pb(Ⅱ) and magnetic ions of Cu(Ⅱ) or Mn(Ⅱ) were also included. The structure chemistry of lanthanide ions in these systems is rich. Coordination numbers from six to ten are discovered, yielding a wide range of coordination geometries including the pentagonal bipyramid, square antiprism, metabidiminished icosahedron, tricapped trigonal prism, capped triangular cupola, etc. The connectivity modes between the Ln polyhedra are miscellaneous, from 3D network, to 2D layer, 1D chain, tetramer, trimer, dimer and finally monomer. A number of compounds display NCS structures and strong SHG response, and many lanthanide compounds exhibit good luminescent properties in visible and IR region.
基金This work was supported by the National Natural Science Foundation of China(Nos.21831001,21571016,91122028)the National Natural Science Foundation of China for Distinguished Young Scholars(No.20725101).
文摘Two new belt-like borates Na_(4)[B_(9)O_(14)(OH)_(3)]·0.5H_(2)O(1)and Na_(5)[B_(9)O_(14)(OH)_(4)](2)have been synthesized under solvothermal conditions.Both compounds contain unprecedented B_(9)O_(16)(OH)_(n)^((n+5))−[n=3(1),4(2)]clusters,which are constructed from four B_(3)O_(3) rings via three BO_(4) tetrahedra.Compound 1 exhibits a rare 1D belt with two types of 8-membered ring(MR)windows based on B_(9)O_(16)(OH)_(3)^(8−) clusters.Compound 2 features two different 1D belts built by different B_(9)O_(16)(OH)_(4)^(9−) units,which is first discovered in borate family.UV-Vis diffuse reflectance spectra reveal that compounds 1 and 2 have the cut-off edges below 190 nm,indicating that they may have potential application in deep UV(DUV)region.
基金supported by the National Natural Science Foundation of China(51872325,51922014,61835014,51972336)the Shanghai Cooperation Organization Science and Technology Partnership Program(2020E01039)+6 种基金Xinjiang Tianshan Youth Program-Outstanding Young Science and Technology Talents(2020Q004)the CAS Youth Interdisciplinary Team(JCTD-2021-18)the West Light Foundation of Chinese Academy of Sciences(2021-XBQNXZ-004)the Scientific Instrument Developing Project,Chinese Academy of Sciences(YJKYYQ20210033)Fujian Innovation Academy,Chinese Academy of Sciences,Key Research Program of Frontier Sciences,Chinese Academy of Sciences(ZDBS-LY-SLH035)Xinjiang Outstanding Young Scientific and Technological Talents(2020Q004)the International Partnership Program of CAS(1A1365kysb20200008)。
文摘The design and synthesis of new deep-ultraviolet(DUV)optical materials are important but challenging.It is well known that the polarizability anisotropy of linear[BO_(2)]^(−)is larger than those of[BO_(3)]^(3−)and[BO_(4)]^(5−),which is the better choice for exploring excellent optical materials.Here,we search for such crystals in borate systems based on the unusual fundamental structural unit[BO_(2)]^(−).By combining the linear[BO_(2)]^(−)with the traditional triangular[BO_(3)]^(3−)and tetrahedral[BO_(4)]^(5−)units,a new mixed metal borate,Rb_(5)Ba_(2)(B_(10)O_(17))_(2)(BO_(2))was obtained via high-temperature solution method.It exhibits excellent optical properties including a DUV transmission window(188 nm)and suitable birefringence(0.06).It also has good thermal stability and its crystal plates can be prepared easily.Furthermore,the strategies of designing borates with[BO_(2)]^(−)units have been proposed from the transformation of crystal framework and the preparation method.
基金Supported by the National Natural Science Foundation of China(Nos.21571016,21831001 and 91122028)the National Natural Science Foundation of China for Distinguished Young Scholars(No.20725101).
文摘Two new alkaline metal borates containing 1D{B5}/{B6}oxoboron helical chains,namely Na0.5[B5O8(OH)2]0.5[B5O6(OH)2]0.5·0.5H3O(1)and NaKCs[B6O9(OH)3](2)were synthesized under solvothermal conditions.Compound 1 contains the interesting alternative left-and right-handed helical{[B5O8(OH)2][B5O6(OH)2]}2-({B5}-1 and{B5}-2)1D chains and compound 2 possesses the similar[B6O11(OH)3]7-({B6})chains.Their 1D chains are further assembled into 2D layers and 3D supramolecular frameworks through O-H…O hydrogen bonds.In addition,the UV cutoff edge of compounds 1 and 2 is both below 190 nm.
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financially supported by the Russian Science Foundation (No.21-19-00097)。
文摘Both numerical and experimental studies of the stability and electronic properties of barium–sodium metaborate Ba_(2)Na_(3)(B_(3)O_(6))_(2)F(P63/m) at pressures up to 10 GPa have been carried out. Electronic-structure calculations with HSE06 hybrid functional showed that Ba_(2)Na_(3)(B_(3)O_(6))_(2)F has an indirect band gap of 6.289 eV. A numerical study revealed the decomposition of Ba_(2)Na_(3)(B_(3)O_(6))_(2)F into the BaB_(2)O_(4),Na BO_(2), and NaF phases above 3.4 GPa at 300 K. Subsequent high-pressure high-temperature experiments performed using ‘Discoverer-1500’DIA-type apparatus at pressures of 3 and 6 GPa and temperature of 1173 K confirmed the stability of Ba_(2)Na_(3)(B_(3)O_(6))_(2)F at 3 GPa and its decomposition into BaB_(2)O_(4), NaBO_(2), and NaF at 6 GPa, which was verified by energy-dispersive X-ray analysis and Raman spectroscopy. The observed Raman bands of the Ba_(2)Na_(3)(B_(3)O_(6))_(2)F phase were assigned by comparing the experimental and calculated spectra. The experimental Raman spectra of decomposition reaction products obtained at 6 GPa suggest the origin of a new high-pressure modification of barium metaborate BaB_(2)O_(4).