In most Suzuki–Miyaura carbon-carbon cross-coupling reactions,the borabicyclo[3.3.1]nonane scaffold(9-BBN)only serves as an auxiliary facilitating the transmetalation step and thus is transformed into by-products.The...In most Suzuki–Miyaura carbon-carbon cross-coupling reactions,the borabicyclo[3.3.1]nonane scaffold(9-BBN)only serves as an auxiliary facilitating the transmetalation step and thus is transformed into by-products.There are rare examples where the 9-BBN derivatives serve as the potentially diverse C8 building blocks in cross-coupling reactions.Herein,we report a cobalt-catalyzed migratory carboncarbon cross-coupling reaction of the in situ formed 9-BBN ate complexes to afford diverse aryl-and alkyl-functionalized cyclooctenes.Preliminary mechanistic studies suggest the oxidation-induced cisbicyclo[3.3.0]oct-1-ylborane is the key intermediate in this migratory cross-coupling reaction,which promotes the development of other diverse migratory cross-coupling of borate complexes.展开更多
The prediction of new fluorooxoborates as ultraviolet(UV)/deep ultraviolet(DUV)opto-electronic functional materials from a largely unexplored chemical space is a challenging task.It has been suggested that the anionic...The prediction of new fluorooxoborates as ultraviolet(UV)/deep ultraviolet(DUV)opto-electronic functional materials from a largely unexplored chemical space is a challenging task.It has been suggested that the anionic frameworks formed by B–O and B–O–F units significantly determine the physical properties of fluorooxoborates.Therefore,the rational design of anionic frameworks could facilitate the materials discovery process.Herein,we propose that a candidate anionic framework can be efficiently derived from an existing one by slightly altering its oxygen content.Following this idea,we hypothesized the existence of a 1D[B_(3)O_(5)F]_(∞)chain from the wellknown 2D[B_(6)O_(9)F_(2_)]_(∞)layer.Accordingly,seven CaB_(3)O_(5)F structures with the expected anionic framework were successfully predicted.First-principles calculations show that all these structures have potential in the UV/DUV birefringent or nonlinear optical(NLO)material field,indicating that the 1D[B_(3)O_(5)F]_(∞)chain is indeed a promising anionic framework for achieving UV/DUV birefringent and NLO performance.展开更多
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
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
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
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
Dissolved copper and iron ions are regarded as friendly and economic catalysts for peroxymonosulfate(PMS)activation,however,neither Cu(Ⅱ)nor Fe(Ⅲ)shows efficient catalytic performance because of the slow rates of Cu...Dissolved copper and iron ions are regarded as friendly and economic catalysts for peroxymonosulfate(PMS)activation,however,neither Cu(Ⅱ)nor Fe(Ⅲ)shows efficient catalytic performance because of the slow rates of Cu(Ⅱ)/Cu(Ⅰ)and Fe(Ⅲ)/Fe(Ⅱ)cycles.Innovatively,we observed a significant enhancement on the degradation of organic contaminants when Cu(Ⅱ)and Fe(Ⅲ)were coupled to activate PMS in borate(BA)buffer.The degradation efficiency of Rhodamine B(RhB,20μmol/L)reached up to 96.3%within 10 min,which was higher than the sum of individual Cu(Ⅱ)-and Fe(Ⅲ)-activated PMS process.Sulfate radical,hydroxyl radical and high-valent metal ions(i.e.,Cu(Ⅲ)and Fe(IV))were identified as the working reactive species for RhB removal in Cu(Ⅱ)/Fe(Ⅲ)/PMS/BA system,while the last played a predominated role.The presence of BA dramatically facilitated the reduction of Cu(Ⅱ)to Cu(Ⅰ)via chelating with Cu(Ⅱ)followed by Fe(Ⅲ)reduction by Cu(Ⅰ),resulting in enhanced PMS activation by Cu(Ⅰ)and Fe(Ⅱ)as well as accelerated generation of reactive species.Additionally,the strong buffering capacity of BA to stabilize the solution pH was satisfying for the pollutants degradation since a slightly alkaline environment favored the PMS activation by coupling Cu(Ⅱ)and Fe(Ⅲ).In a word,this work provides a brand-new insight into the outstanding PMS activation by homogeneous bimetals and an expanded application of iron-based advanced oxidation processes in alkaline conditions.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
Designing transition metal nickel-cobalt-based battery-type electrode materials driven by anions is crucial for achieving rapid OH-ion transport under electrochemical activation conditions,thereby improving capacitanc...Designing transition metal nickel-cobalt-based battery-type electrode materials driven by anions is crucial for achieving rapid OH-ion transport under electrochemical activation conditions,thereby improving capacitance performance.Herein,borate anions are selected through theoretical calculations,and twodimensional(2D)defect-rich amorphous nickel-cobalt-based borate is synthesized via a facile chemical reduction method.Under potentiostatic modification,activated products(NCB-G-E)are obtained.In situ Raman spectra reveal that electron-deficient borate extracts electrons from metal centers,facilitating the oxidation state transition of Ni and Co.Theoretical calculations show that in situ adsorbed borate regulates the d-band centers of metal sites,enhancing OH^(-)intermediate adsorption.Meanwhile,borate anion adsorption accelerates the deprotonation and activation processes.Electrochemical tests demonstrate that NCB-G-E displays superior capacitance performance,with a high quality specific capacity of383.3 mA h g^(-1)and 65% retention rate at 30 A g^(-1),surpassing most nickel-cobalt-based electrodes.The assembled asymmetric supercapacitor presents an impressive energy density of 68.2 Wh kg^(-1)and good cycling stability.This work highlights the role of electron-deficient borate in tuning metal band structure and promoting oxidation state transition through synergistic defect advantages,offering new prospects for advanced battery-type energy storage materials.展开更多
As a promising candidate,the fluorooxoborate has enkindled new explorations of nonlinear optical materials to meet the deep-ultraviolet criteria.However,big challenges and open questions still remain facing this excit...As a promising candidate,the fluorooxoborate has enkindled new explorations of nonlinear optical materials to meet the deep-ultraviolet criteria.However,big challenges and open questions still remain facing this exciting new field,especially the birefringence and dispersion of refractive index which are fundamental parameters for determining the phasematching second harmonic generation wavelength.Here we designed possible anionic groups in fluorooxoborates,and analyzed the optical anisotropy to check its influence on birefringence,which was proved further by the response electronic distribution anisotropy approximation.The functional modules modulating birefringence in fluorooxoborates were explored systematically.We developed an approach for evaluating the behavior of the refractive index dispersions and found that the fluorooxoborates had small refractive index dispersions owing to the introduction of fluorooxoborate modules.Our results demonstrate that fluorooxoborates can be utilized to realize short phase-matching wavelength markedly and offer a path toward novel performance-driven materials design.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
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
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
基金supported by the National Natural Science Foundation of China(No.22171046)the Hundred-Talent Project of Fujian(No.50021113)Fuzhou University(No.0480-00489503)。
文摘In most Suzuki–Miyaura carbon-carbon cross-coupling reactions,the borabicyclo[3.3.1]nonane scaffold(9-BBN)only serves as an auxiliary facilitating the transmetalation step and thus is transformed into by-products.There are rare examples where the 9-BBN derivatives serve as the potentially diverse C8 building blocks in cross-coupling reactions.Herein,we report a cobalt-catalyzed migratory carboncarbon cross-coupling reaction of the in situ formed 9-BBN ate complexes to afford diverse aryl-and alkyl-functionalized cyclooctenes.Preliminary mechanistic studies suggest the oxidation-induced cisbicyclo[3.3.0]oct-1-ylborane is the key intermediate in this migratory cross-coupling reaction,which promotes the development of other diverse migratory cross-coupling of borate complexes.
基金supported by the National Natural Science Foundation of China(Grant No.52403305)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0880000)+1 种基金Tianchi Talent Program of Xinjiang Uygur Autonomous Region(Grant No.2024000068)Postdoctoral Fellow-ship Program(Grade C)(Grant No.GZC20232959)。
文摘The prediction of new fluorooxoborates as ultraviolet(UV)/deep ultraviolet(DUV)opto-electronic functional materials from a largely unexplored chemical space is a challenging task.It has been suggested that the anionic frameworks formed by B–O and B–O–F units significantly determine the physical properties of fluorooxoborates.Therefore,the rational design of anionic frameworks could facilitate the materials discovery process.Herein,we propose that a candidate anionic framework can be efficiently derived from an existing one by slightly altering its oxygen content.Following this idea,we hypothesized the existence of a 1D[B_(3)O_(5)F]_(∞)chain from the wellknown 2D[B_(6)O_(9)F_(2_)]_(∞)layer.Accordingly,seven CaB_(3)O_(5)F structures with the expected anionic framework were successfully predicted.First-principles calculations show that all these structures have potential in the UV/DUV birefringent or nonlinear optical(NLO)material field,indicating that the 1D[B_(3)O_(5)F]_(∞)chain is indeed a promising anionic framework for achieving UV/DUV birefringent and NLO performance.
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.
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.
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 Sichuan Science and Technology Program(No.2021YJ0385)the Project in Yangtze River Ecological Environment Protection and Restoration(No.2022-LHYJ-02-0509-08).
文摘Dissolved copper and iron ions are regarded as friendly and economic catalysts for peroxymonosulfate(PMS)activation,however,neither Cu(Ⅱ)nor Fe(Ⅲ)shows efficient catalytic performance because of the slow rates of Cu(Ⅱ)/Cu(Ⅰ)and Fe(Ⅲ)/Fe(Ⅱ)cycles.Innovatively,we observed a significant enhancement on the degradation of organic contaminants when Cu(Ⅱ)and Fe(Ⅲ)were coupled to activate PMS in borate(BA)buffer.The degradation efficiency of Rhodamine B(RhB,20μmol/L)reached up to 96.3%within 10 min,which was higher than the sum of individual Cu(Ⅱ)-and Fe(Ⅲ)-activated PMS process.Sulfate radical,hydroxyl radical and high-valent metal ions(i.e.,Cu(Ⅲ)and Fe(IV))were identified as the working reactive species for RhB removal in Cu(Ⅱ)/Fe(Ⅲ)/PMS/BA system,while the last played a predominated role.The presence of BA dramatically facilitated the reduction of Cu(Ⅱ)to Cu(Ⅰ)via chelating with Cu(Ⅱ)followed by Fe(Ⅲ)reduction by Cu(Ⅰ),resulting in enhanced PMS activation by Cu(Ⅰ)and Fe(Ⅱ)as well as accelerated generation of reactive species.Additionally,the strong buffering capacity of BA to stabilize the solution pH was satisfying for the pollutants degradation since a slightly alkaline environment favored the PMS activation by coupling Cu(Ⅱ)and Fe(Ⅲ).In a word,this work provides a brand-new insight into the outstanding PMS activation by homogeneous bimetals and an expanded application of iron-based advanced oxidation processes in alkaline conditions.
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.
基金supported by the National Natural Science Foundation of China(22478422,22238012,and 22178384)Science Foundation of China University of Petroleum,Beijing(2462024QNXZ003)CHN Energy Investment Group(GJNY23-23)。
文摘Designing transition metal nickel-cobalt-based battery-type electrode materials driven by anions is crucial for achieving rapid OH-ion transport under electrochemical activation conditions,thereby improving capacitance performance.Herein,borate anions are selected through theoretical calculations,and twodimensional(2D)defect-rich amorphous nickel-cobalt-based borate is synthesized via a facile chemical reduction method.Under potentiostatic modification,activated products(NCB-G-E)are obtained.In situ Raman spectra reveal that electron-deficient borate extracts electrons from metal centers,facilitating the oxidation state transition of Ni and Co.Theoretical calculations show that in situ adsorbed borate regulates the d-band centers of metal sites,enhancing OH^(-)intermediate adsorption.Meanwhile,borate anion adsorption accelerates the deprotonation and activation processes.Electrochemical tests demonstrate that NCB-G-E displays superior capacitance performance,with a high quality specific capacity of383.3 mA h g^(-1)and 65% retention rate at 30 A g^(-1),surpassing most nickel-cobalt-based electrodes.The assembled asymmetric supercapacitor presents an impressive energy density of 68.2 Wh kg^(-1)and good cycling stability.This work highlights the role of electron-deficient borate in tuning metal band structure and promoting oxidation state transition through synergistic defect advantages,offering new prospects for advanced battery-type energy storage materials.
基金supported by the National Natural Science Foundation of China(51922014,11774414,51972336 and 61835014)the Key Research Program of Frontier Sciences,CAS(ZDBSLY-SLH035)+2 种基金Tianshan Innovation Team Program(2018D14001)the Western Light Foundation of CAS(Y92S191301)Fujian Institute of Innovation,CAS。
文摘As a promising candidate,the fluorooxoborate has enkindled new explorations of nonlinear optical materials to meet the deep-ultraviolet criteria.However,big challenges and open questions still remain facing this exciting new field,especially the birefringence and dispersion of refractive index which are fundamental parameters for determining the phasematching second harmonic generation wavelength.Here we designed possible anionic groups in fluorooxoborates,and analyzed the optical anisotropy to check its influence on birefringence,which was proved further by the response electronic distribution anisotropy approximation.The functional modules modulating birefringence in fluorooxoborates were explored systematically.We developed an approach for evaluating the behavior of the refractive index dispersions and found that the fluorooxoborates had small refractive index dispersions owing to the introduction of fluorooxoborate modules.Our results demonstrate that fluorooxoborates can be utilized to realize short phase-matching wavelength markedly and offer a path toward novel performance-driven materials design.
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(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.