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Bioinspired polydopamine interface reinforced boron-Viton composites with high structure stability and energy releasing efficiency
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作者 Liu Yang Liu Yuezhou +2 位作者 Gao Fulei Liu Yingzhe Wang Yinglei 《Defence Technology(防务技术)》 2026年第1期330-339,共10页
Boron has attracted increasing attention in the field of high-energy explosives and propellants due to its high volume calorific value and mass calorific value.However,the complicated combustion process and low combus... Boron has attracted increasing attention in the field of high-energy explosives and propellants due to its high volume calorific value and mass calorific value.However,the complicated combustion process and low combustion efficiency hinder its wide application.To tackle this challenge,bioinspired polydopamine(PDA)interface reinforced boron-Viton composites,with high structure stability and excellent energy releasing efficiency,are designed and prepared,combining the interface regulation of PDA biomimetic materials and combustion promotion of fluoropolymers.Firstly,the stronger adsorption energy of PDA with boron compared to Viton is demonstrated by molecular dynamics simulations.Next,B@PDA@Viton is prepared by the combination of in-situ dopamine polymerization and solvent/nonsolvent method,and the double-layer core-shell structure is confirmed by XPS,FTIR,and TEM characterizations.TG-DSC analysis shows that B@PDA@Viton possesses superior thermal properties,with a 55.48%increase in oxidation heat compared to raw B.Furthermore,ignition and combustion performance tests indicate that B@PDA@Viton reduces ignition delay by 57.56%and increases heat of combustion by 68.63%relative to raw B.These findings elucidate the ignition and combustion mechanisms of B@PDA@Viton.This work not only developed high-performance boron-based composite fuels but also provided insights into the development of boron-based fuels. 展开更多
关键词 boron powder POLYDOPAMINE Ignition and combustion PROPELLANT Energetic materials
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A high-energy powder with excellent combustion reaction performance:Surface modification strategy of boron powder based on non-thermal plasma
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作者 Kangkang Li Jianyong Xu +9 位作者 Xiaoting Lei Mengzhe Yang Jing Liu Luqi Guo Pengfei Cui Dihua Ouyang Chunpei Yu He Cheng Jiahai Ye Wenchao Zhang 《Defence Technology(防务技术)》 2026年第1期289-300,共12页
The presence of a surface oxide film(B_(2)O_(3))on boron(B)particles significantly compromises their combustion efficiency and kinetic performance in fuel-rich solid propellants.This study proposes an innovative conti... The presence of a surface oxide film(B_(2)O_(3))on boron(B)particles significantly compromises their combustion efficiency and kinetic performance in fuel-rich solid propellants.This study proposes an innovative continuous modification strategy combining non-thermal plasma(NTP)etching with fluorocarbon passivation.Characterization and kinetic analysis revealed that reactive plasma species—including atomic hydrogen(H),electronically excited molecular hydrogen(H_(2)^(*)),vibrationally excited molecular hydrogen(H_(2)v),and hydrogen ions(H^(+))—dominate the reduction of B_(2)O_(3)through lowering the transition energy barrier and shifting the reaction spontaneity.Subsequent argon plasma fragmentation of C_(8)F_(18)generates fluorocarbon radicals that form conformal passivation coatings(thickness:7 nm)on purified boron surfaces.The modified boron particles exhibit 37.5℃lower exothermic peak temperature and 27.2%higher heat release(14.8 kJ/g vs.11.6 kJ/g)compared to untreated counterparts.Combustion diagnostics reveal 194%increase in maximum flame height(135.10 mm vs.46.03 mm)and 134%enhancement in flame propagation rate(4.44 cm/s vs.1.90 cm/s).This NTP-based surface engineering approach establishes a scalable pathway for developing highperformance boron-based energetic composites. 展开更多
关键词 Oxide film materials Surface modification boron powder Non-thermal plasma Combustion performance
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Boosting peroxymonosulfate activated for emerging contaminant removal:The synergy of boron doping in regulating the interfacial electric field of FeNC
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作者 Shiyu Zuo Yan Wang +2 位作者 Jinquan Wan Jianxin Yi JoséAlemáne 《Journal of Environmental Sciences》 2026年第1期97-107,共11页
Peroxymonosulfate(PMS)-based advanced oxidation processes(AOPs)are an effective way to remove emerging contaminants(ECs)from water.The catalytic process involving PMS is hindered by the suboptimal electron trans-fer e... Peroxymonosulfate(PMS)-based advanced oxidation processes(AOPs)are an effective way to remove emerging contaminants(ECs)from water.The catalytic process involving PMS is hindered by the suboptimal electron trans-fer efficiency of current catalysts,the further application of AOPs technology is limited.Here,it is proposed that the interfacial electric field can be controlled by bor(B)-doped FeNC catalysts,which shows significant advantages in the efficient generation,release and participation of reactive oxygen species(ROS)in the reaction.The super exchange interaction between Fe sites and N and B sites is realized through the directional transfer of electrons in the interfacial electric field,which ensures the high efficiency and stability of the PMS catalytic process.B doping increases the d orbitals distribution at Fermi level,which facilitates enhanced electron transition activity,thereby promoting the effective generation of (1)^O_(2).At the same time,orbital hybridization causes the center of the d band to move to a lower energy level,which not only contributes to the desorption process of (1)^O_(2),but also accelerates its release.In addition,B-doping also improved the adsorption capacity of organic pollutants and shortened the migration distance of ROS,thereby significantly improving the degradation efficiency of ECs.The B-doping strategy outlined offers a novel approach to the development of FeNC catalysts,it lays a theoretical foundation and offers technical insights for the integration of PMS/AOPs technology in the ECs management. 展开更多
关键词 Interfacial electric field boron doping Electronic transfer Peroxymonosulfate Emerging contaminants
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An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes
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作者 Ying Wang Kai Zhang +10 位作者 Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu Jin Zhang Yagang Yao 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期548-558,共11页
Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their development.The primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid ... Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their development.The primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid boron.In this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B system.This approach can be adopted to form various low-melting-point AM–Mg–B–O growth systems.These growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN chains.These findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs. 展开更多
关键词 boron nitride nanotubes LOW-TEMPERATURE boron activation Density functional theory
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Low pressure synthesis of boron nitride with (C_2H_5)_2O·BF_3 and Li_3N precursor 被引量:1
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作者 王少波 徐晓伟 +1 位作者 范慧丽 李玉萍 《Journal of Central South University of Technology》 EI 2005年第1期60-63,共4页
Cubic boron nitride(c-BN) was synthesized through benzene thermal method at a lower temperature of (300℃) by selecting liquid((C2H5)2O·)BF3 and Li3N as reactants. Hexagonal boron nitride(h-BN) and orth... Cubic boron nitride(c-BN) was synthesized through benzene thermal method at a lower temperature of (300℃) by selecting liquid((C2H5)2O·)BF3 and Li3N as reactants. Hexagonal boron nitride(h-BN) and orthorhombic boron nitride(o-BN) were also obtained. The samples were characterized by X-ray powder diffractometry and Fourier transformation infrared spectroscopy. The results show that all the BF3, BCl3 and BBr3 in the same family compounds can react with Li3N to synthesize BN since the strongest bond of B—F can be broken. Compared with BBr3, liquid (C2H5)2O·BF3 is cheaper, less toxic and more convenient to operate. Li3N not only provides nitrogen source but also has catalytic effect on accelerating the formation of c-BN at low temperature and pressure. 展开更多
关键词 benzene thermal method boron nitride boron trifluoride etherate lithium nitride cubic boron (nitride ) orthorhombic boron nitride hexagonal boron nitride
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The synthesis and evaluation of novel BPA derivatives for enhanced blood-brain barrier penetration and boron neutron capture therapy
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作者 Shushan Mo Zhaoshuo Wang +8 位作者 Dandan Ding Zhengzheng Yan Yunlu Dai Jinchao Zhang Huifang Liu Tianjiao Liang Jianfei Tong Zhenhua Li Xueyi Wang 《Chinese Chemical Letters》 2025年第5期442-447,共6页
Boron neutron capture therapy(BNCT)has emerged as a promising treatment for cancers,offering a unique approach to selectively target tumor cells while sparing healthy tissues.Despite its clinical utility,the widesprea... Boron neutron capture therapy(BNCT)has emerged as a promising treatment for cancers,offering a unique approach to selectively target tumor cells while sparing healthy tissues.Despite its clinical utility,the widespread use of fructose-BPA(F-BPA)has been hampered by its limited ability to penetrate the blood-brain barrier(BBB)and potential risks for patients with certain complications such as diabetes,hyperuricemia,and gout,particularly with substantial dosages.Herein,a series of novel BPA derivatives were synthesized.After the primary screening,geniposide-BPA(G-BPA)and salidroside-BPA(S-BPA)exhibited high water solubility,low cytotoxicity and safe profiles for intravenous injection.Furthermore,both G-BPA and S-BPA had demonstrated superior efficacy in vitro against the 4T1 cell line compared with F-BPA.Notably,S-BPA displayed optimal BBB penetration capability,as evidenced by in vitro BBB models and glioblastoma models in vivo,surpassing all other BPA derivative candidates.Meanwhile,GBPA also exhibited enhanced performance relative to the clinical drug F-BPA.In brief,G-BPA and S-BPA,as novel BPA derivatives,demonstrated notable safety profiles and remarkable boron delivery capabilities,thereby offering promising therapeutic options for BNCT in the clinic. 展开更多
关键词 boron neutron capture therapy(BNCT) Novel BPA derivatives boron drug development BBB penetration Glioblastoma
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Exploiting selective isotope exchange of amino–phenolic networks for boron-10 isotopologue separation
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作者 Nanjiong Pang Yunxiang He +4 位作者 Mingyao Wang Xiaoling Wang Junling Guo Xuepin Liao Bi Shi 《Chinese Chemical Letters》 2025年第10期270-275,共6页
Although the demand of ^(10)B separation has arisen in the 1930s,^(10)B/^(11)B are among the most difficult isotopes to separate due to the extremely similar relative atomic mass.Herein,we report an efficient separati... Although the demand of ^(10)B separation has arisen in the 1930s,^(10)B/^(11)B are among the most difficult isotopes to separate due to the extremely similar relative atomic mass.Herein,we report an efficient separation of ^(10)B isotopologue by engineering amino-galloyl synergistic materials via a selective adsorption and isotope exchange reaction,achieving a record-high single-stage separation factor of 1.048 with ^(10)B abundance up to 21.42%.^(11)B MAS NMR results and DFT calculations reveal that the galloyl groups exhibit inherent high affinity for B(OH)4-,forming tetrahedral sp^(3) B-galloyl complexes.The relatively higher ^(10)B–O bond energy of ^(10)B-galloyl complexes facilitates the isotope exchange between11B in B-galloyl complexes and ^(10)B in B(OH)_(3).Flowthrough dynamic separation in fixed-bed demonstrates the feasibility and potential of large-scale deployment of this method in real-world,suggesting a promising avenue for the exploitation of more efficient enrichment of ^(10)B for the sustainable nuclear energy and biomedical research. 展开更多
关键词 boron isotopologue separation Amino-phenolic networks POLYPHENOL boron isotope exchange ^(10)B enrichment
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Using Targeted Phonon Excitation to Modulate Thermal Conductivity of Boron Nitride
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作者 Dongkai Pan Tianhao Li +3 位作者 Xiao Wan Zhicheng Zong Yangjun Qin Nuo Yang 《Chinese Physics Letters》 2025年第7期449-453,共5页
Recent advancements in thermal conductivity modulating strategies have shown promising enhancements to the thermal management capabilities of two-dimensional materials.In this article,both the iterative Boltzmann tran... Recent advancements in thermal conductivity modulating strategies have shown promising enhancements to the thermal management capabilities of two-dimensional materials.In this article,both the iterative Boltzmann transport equation solution and the two-temperature model were employed to investigate the efficacy of targeted phonon excitation applied to hexagonal boron nitride(hBN).The results indicate significant modifications to hBN's thermal conductivity,achieving increases of up to 30.1%as well as decreases of up to 59.8%.These findings validate the reliability of the strategy,expand its scope of applicability,and establish it as a powerful tool for tailoring thermal properties across a wider range of fields. 展开更多
关键词 thermal conductivityachieving thermal management capabilities boron nitride targeted phonon excitation iterative boltzmann transport equation solution hexagonal boron nitride hbn thermal conductivity modulating strategies thermal conductivity
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Symmetry-Breaking Strain Drives Significant Reduction in Lattice Thermal Conductivity:A Case Study of Boron Arsenide
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作者 Kaile Chen Xin Jin Xiaolong Yang 《Chinese Physics Letters》 2025年第12期358-374,共17页
Recent research has revealed that cubic boron arsenide(BAs)exhibits a non-monotonic pressure dependence of lattice thermal conductivity(κ_(L))under isotropic strain.Here,through rigorous first-principles calculations... Recent research has revealed that cubic boron arsenide(BAs)exhibits a non-monotonic pressure dependence of lattice thermal conductivity(κ_(L))under isotropic strain.Here,through rigorous first-principles calculations,we unveil that anisotropic strain induces a monotonic reduction in the κ_(L) of BAs-a striking contrast to the isotropic scenario.The results show that applying uniaxial[100]strain leads to the lifting of phonon band degeneracy,accompanied by an overall softening of the phonon spectrum.These modifications significantly increase phonon-phonon scattering channels by facilitating the fulfillment of selection rules,resulting in a concurrent increase in both three-and four-phonon scattering rates.Consequently,κ_(L) exhibits a dramatic suppression of nearly 80%under large tension at room temperature.Meanwhile,we unexpectedly observe that the uniaxial strain suppresses κ_(L) much more strongly in the direction perpendicular to the strain than along the stretching direction.This work establishes the fundamental understanding of the thermal conductivity behavior of BAs under anisotropic strain and opens a promising avenue for manipulating solid-state heat transport by tuning lattice crystal symmetry. 展开更多
关键词 phonon band degeneracy lifting phonon band degeneracyaccompanied softening phonon spectrumthese boron arsenide boron arsenide bas exhibits lattice thermal conductivity symmetry breaking strain anisotropic strain
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Study on hydrogen-based reduction of boron-bearing iron concentrate and separation of slag-iron at low temperatures
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作者 LI Yu GUO Zhancheng 《Baosteel Technical Research》 2025年第2期13-22,共10页
The hydrogen-based reduction and electric smelting technology is a green and low-carbon process for treating low-grade ore and complex symbiotic iron ore.In this study,the hydrogen-based reduction of boron-bearing iro... The hydrogen-based reduction and electric smelting technology is a green and low-carbon process for treating low-grade ore and complex symbiotic iron ore.In this study,the hydrogen-based reduction of boron-bearing iron concentrate and the low-temperature separation compared with the high-temperature melting separation of slag and iron from a boron-bearing iron concentrate were studied.The metallization rate of the boron-bearing iron concentrate reached 99.63%after hydrogen-based reduction at 1050℃,and the metallic iron was interwoven with olivine(Mg_(2)SiO_(4))in the reduced ore.In addition,the high-temperature melting separation of iron and slag could be accomplished at 1550℃for 60 min,where boron was mainly distributed in the form of a glass phase in the slag with a mass fraction of B_(2)O_(3)of 22.69%,and 0.35%of boron(mass fraction)was melted into liquid iron.By contrast,iron and slag were efficiently separated at a lower temperature(1300℃)for 10 min and enhanced by super-gravity.Almost all the boron content was enriched into a suanite phase in the slag with a considerably high mass fraction of B_(2)O_(3)(35.61%)and a high recovery ratio(99.37%),and the mass fraction of boron decreased to 0.15%in iron.Compared with high-temperature melting separation,low-temperature separation combined with hydrogen-based reduction greatly improved the enrichment of boron in slag and prevented the melting of boron into iron. 展开更多
关键词 boron-bearing iron concentrate hydrogen-based reduction electric smelting low-temperature separ-ation boron enrichment
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Molybdenum-doped carbon nitride as an efficient heterogeneous catalyst for direct amination of nitroarenes with arylboronic acids 被引量:1
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作者 Wen-Jing Li Jun-Bo Wang +2 位作者 Yu-Heng Liu Mo Zhang Zhan-Hui Zhang 《Chinese Chemical Letters》 2025年第3期282-289,共8页
Heterogeneous metal-catalyzed chemical conversions with a recyclable catalyst are very ideal and challenging for sustainable organic synthesis.A new bipyridyl-Mo(IV)-carbon nitride(CN-K/Mo-Bpy)was prepared by supporti... Heterogeneous metal-catalyzed chemical conversions with a recyclable catalyst are very ideal and challenging for sustainable organic synthesis.A new bipyridyl-Mo(IV)-carbon nitride(CN-K/Mo-Bpy)was prepared by supporting molybdenum complex on C_(3)N_(4)-K and characterized by FT-IR,XRD,SEM,XPS and ICP-OES.Heterogeneous CN–Mo-Bpy catalyst can be applied to the direct amination of nitroarenes and arylboronic acid,thus constructing various valuable diarylamines in high to excellent yields with a wide substrate scope and good functional group tolerance.It is worth noting that this heterogeneous catalyst has high chemical stability and can be recycled for at least five times without reducing its activity. 展开更多
关键词 Heterogeneous catalysis Carbon nitride MOLYBDENUM NITROARENES boronic acids AMINATION
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Multi boron-doping effects in hard carbon toward enhanced sodium ion storage 被引量:1
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作者 Peng Zheng Wang Zhou +7 位作者 Ying Mo Biao Zheng Miaomiao Han Qin Zhong Wenwen Yang Peng Gao Lezhi Yang Jilei Liu 《Journal of Energy Chemistry》 2025年第1期730-738,共9页
Hard carbon (HC) has been considered as promising anode material for sodium-ion batteries (SIBs).The optimization of hard carbon’s microstructure and solid electrolyte interface (SEI) property are demonstrated effect... Hard carbon (HC) has been considered as promising anode material for sodium-ion batteries (SIBs).The optimization of hard carbon’s microstructure and solid electrolyte interface (SEI) property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly desirable.Herein,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage sites.In-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy (FTIR/EIS) and X-ray photoelectron spectroscopy (XPS) analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate performance.As a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling performance.In general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance. 展开更多
关键词 Hard carbon Sodium-ion batteries boron doping Pore structure Electrode/electrolyte interphases
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Boron cluster-based TADF emitter via through-space charge transfer enabling efficient orange-red electroluminescence 被引量:1
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作者 Xiao Yu Dongyue Cui +8 位作者 Mengmeng Wang Zhaojin Wang Mengzhu Wang Deshuang Tu Vladimir Bregadze Changsheng Lu Qiang Zhao Runfeng Chen Hong Yan 《Chinese Chemical Letters》 2025年第3期232-238,共7页
Thermally activated delayed fluorescence(TADF)materials driven by a through-space charge transfer(TSCT)mechanism have garnered wide interest.However,access of TSCT-TADF molecules with longwavelength emission remains a... Thermally activated delayed fluorescence(TADF)materials driven by a through-space charge transfer(TSCT)mechanism have garnered wide interest.However,access of TSCT-TADF molecules with longwavelength emission remains a formidable challenge.In this study,we introduce a novel V-type DA-D-A’emitter,Trz-mCzCbCz,by using a carborane scaffold.This design strategically incorporates carbazole(Cz)and 2,4,6-triphenyl-1,3,5-triazine(Trz)as donor and acceptor moieties,respectively.Theoretical calculations alongside experimental validations affirm the typical TSCT-TADF characteristics of this luminogen.Owing to the unique structural and electronic attributes of carboranes,Trz-mCzCbCz exhibits an orange-red emission,markedly diverging from the traditional blue-to-green emissions observed in classical Cz and Trz-based TADF molecules.Moreover,bright emission in aggregates was observed for Trz-mCzCbCz with absolute photoluminescence quantum yield(PLQY)of up to 88.8%.As such,we have successfully fabricated five organic light-emitting diodes(OLEDs)by utilizing Trz-mCzCbCz as the emitting layer.It is important to note that both the reverse intersystem crossing process and the TADF properties are profoundly influenced by host materials.The fabricated OLED devices reached a maximum external quantum efficiency(EQE)of 12.7%,with an emission peak at 592 nm.This represents the highest recorded efficiency for TSCT-TADF OLEDs employing carborane derivatives as emitting layers. 展开更多
关键词 Thermally activated delayed fluorescence Through-space charge transfer CARBORANE boron clusters Organic light-emitting diodes
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Preparation of Low Ratio Magnesium Ccement by Acid Leaching Treatment of Boron Mud
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作者 YANG Mei ZHANG Mingzhe CHEN Hao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期120-129,共10页
The effects of liquid-solid ratio and reaction time on the leaching rate of magnesium at room temperature were investigated,as well as the effects of the molar ratio of MgO/MgCl_(2),the amount of water added,and the a... The effects of liquid-solid ratio and reaction time on the leaching rate of magnesium at room temperature were investigated,as well as the effects of the molar ratio of MgO/MgCl_(2),the amount of water added,and the amount of acid-impregnated slag dosed on the compressive strength and water resistance of LR-MOC.The results showed that the magnesium element in the boron mud could be maximally leached under the conditions of 1:1 concentration of hydrochloric acid at room temperature,liquid-solid ratio of 2.5 mL·g^(-1),and reaction time of 5 h,and the main products were amorphous SiO_(2) as well as a small amount of magnesium olivine which had not been completely reacted.The LR-MOC prepared using the acid-soaked mixture could reach a softening coefficient of 0.85 for 28 d of water immersion when the molar ratio of MgO/MgCl_(2) was 2.2,the amount of water added was 0 g,and the acid-soaked slag dosing was 40 wt%,which also led to an appreciable late-strength,with an increase of 19.4%in compressive strength at 28 d compared to that at 7 d.Unlike previous studies,LR-MOC prepared in this way has a final strength phase that is not the more easily hydrolysed 3-phase but the lath-like 5-phase.For this phenomenon,we analyzed the mechanism and found that,during the acid leaching process,a part of amorphous SiO_(2) dissolved in the acid leaching solution formed a silica sol,in which Mg^(2+)played a bridging role to make the silica sol more stable.With the addition and hydrolysis of MgO,the silica sol gel coagulation slows down,providing a capping layer to inhibit the hydrolysis of the 5-phase crystals and providing some strength after coagulation.The amorphous SiO_(2) in the other part of the acid-impregnated slag generated M-S-H gel with Mg^(2+)and OH-,which synergised with the dense structure composed of interlocking crystals to improve the water resistance of LR-MOC. 展开更多
关键词 boron mud magnesium chloride-oxygen cement acid immersion water resistance silica sol
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Significantly Enhanced Oxygen Reduction Reaction Activity in Co-N-C Catalysts through Synergistic Boron Doping
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作者 Chang Lan Jing-Sen Bai +8 位作者 Xin Guan Shuo Wang Nan-Shu Zhang Yu-Qing Cheng Jin-Jing Tao Yu-Yi Chu Mei-Ling Xiao Chang-Peng Liu Wei Xing 《电化学(中英文)》 北大核心 2025年第9期56-68,共13页
The weak adsorption energy of oxygen-containing intermediates on Co center leads to a considerable performance dis-parity between Co-N-C and costly Pt benchmark in catalyzing oxygen reduction reaction(ORR).In this wor... The weak adsorption energy of oxygen-containing intermediates on Co center leads to a considerable performance dis-parity between Co-N-C and costly Pt benchmark in catalyzing oxygen reduction reaction(ORR).In this work,we strategi-cally engineer the active site structure of Co-N-C via B substitution,which is accomplished by the pyrolysis of ammonium borate.During this process,the in-situ generated NH_(3)gas plays a critical role in creating surface defects and boron atoms substituting nitrogen atoms in the carbon structure.The well-designed CoB_(1)N_(3)active site endows Co with higher charge density and stronger adsorption energy toward oxygen species,potentially accelerating ORR kinetics.As expected,the resulting Co-B/N-C catalyst exhibited superior ORR performance over Co-N-C counterpart,with 40 mV,and fivefold en-hancement in half-wave potential and turnover frequency(TOF).More importantly,the excellent ORR performance could be translated into membrane electrode assembly(MEA)in a fuel cell test,delivering an impressive peak power density of 824 mW·cm^(-2),which is currently the best among Co-based catalysts under the same conditions.This work not only demon-strates an effective method for designing advanced catalysts,but also affords a highly promising non-precious metal ORR electrocatalyst for fuel cell applications. 展开更多
关键词 Oxygen reduction reaction Proton exchange membrane fuel cell Single-atom catalyst Co-N-C boron doping
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Effect of Na_2CO_3 on reduction and melting separation of ludwigite/coal composite pellet and property of boron-rich slag 被引量:3
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作者 王广 薛庆国 王静松 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第1期282-293,共12页
The effects of Na_2CO_3 on the reduction and melting separation behavior of ludwigite/coal composite pellet, the desulfurization ratio and the property of the separated boron-rich slag were investigated at laboratory ... The effects of Na_2CO_3 on the reduction and melting separation behavior of ludwigite/coal composite pellet, the desulfurization ratio and the property of the separated boron-rich slag were investigated at laboratory scale in the present work. Na_2CO_3 could improve the reduction rate of the composite pellet to some extent. The melting separation of the composite pellet became increasingly difficult with the increase of Na_2CO_3 in the pellet due to the sharply increasing of the melting point of slag. The sulfur content of the iron nugget gradually decreased from 0.27% to 0.084%(mass fraction) with the Na_2CO_3 content in the pellet increasing from 0 to 6%. The efficiency of extraction of boron(EEB) of the slow cooled boron-rich slag decreased from 86.46% to 59.52% synchronously. Na_2CO_3 had obviously negative effect on melting separation of the composite pellet and boron extraction of the boron-rich slag. 展开更多
关键词 LUDWIGITE carbon composite pellet reduction and melting separation DESULFURIZATION boron-rich slag boron extraction
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Unraveling boron-organic template interactions in[B,Al]-ZSM-5 zeolite using solid-state NMR spectroscopy
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作者 Yongxiang Wang Shuangqin Zeng +8 位作者 Pengfei Wang Mingji Zheng Weidong Huang Yueying Chu Ningdong Feng Guodong Qi Qiang Wang Jun Xu Feng Deng 《Magnetic Resonance Letters》 2025年第2期69-78,共10页
Organic structure directingagents(OSDAs),suchas tetrapropylammonium(TPA)cations,serve as crucial templates for the formation of zeolite frameworks.These organic molecules interact with inorganic species,guiding the as... Organic structure directingagents(OSDAs),suchas tetrapropylammonium(TPA)cations,serve as crucial templates for the formation of zeolite frameworks.These organic molecules interact with inorganic species,guiding the assembly of the zeolite structure.In this study,we inves-tigate the complex interplay between boron species and TPA cations during the crystallization of[B,Al]-ZSM-5 zeolites.Two-dimensional(2D)11B-{1H}cross-polarization heteronuclear correlation(CP-HECTOR)NMRexperiments elucidate distinct interactions between two boron species,B(IV)-1 and B(IV)-2,and the propyl chain of the TPAs.Amorphous B(IV)-1 species exhibit a strong preference for proximity to the nitrogen cation center of the OSDAs,while framework B(IV)-2 species engage with components situated at greater distances from the cation center.Moreover,13C-{11B}symmetry-based resonance-echo saturation-pulse double-resonance(S-RESPDOR)experiments revealed that framework boron species preferentially occupy the straight channels of the MFI structure,as evidenced by their interaction with specificmethyl groups on the TPAmolecules.This observation provides valuable insights into the crystallization mechanism of boron-based zeolites,suggesting that the conformation and orientation of the OSDA molecules play a critical role in determining the location of boron atoms within the zeolite framework. 展开更多
关键词 OSDAs Solid-state NMR boron Zeolites CRYSTALLIZATION
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Transcription factor BnaA1.WRKY53 is involved in regulation of auxin-induced leaf curling under boron deficiency in Brassica napus
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作者 Jinliang Yao Rui Cui +4 位作者 Beibei Fang Sheliang Wang Xiangsheng Ye Zhaojun Liu Fangsen Xu 《The Crop Journal》 2025年第4期1068-1080,共13页
Brassica napus(oilseed rape)is sensitive to boron(B)deficiency and exhibits young leaf curling in response to low-B stress at the seedling stage,which leads to reduced photosynthesis and plant growth.So far,no gene ha... Brassica napus(oilseed rape)is sensitive to boron(B)deficiency and exhibits young leaf curling in response to low-B stress at the seedling stage,which leads to reduced photosynthesis and plant growth.So far,no gene has been identified to be involved in B deficiency induced leaf curling.Our previous results showed the transcription factor BnaA1.WRKY53 might be involved in B-deficiency tolerance.However,altered BnaA1.WRKY53 expression does not influence B concentration in shoot,root and leaf cell walls,which suggests Bna A1.WRKY53 might be involved in other biological processes.Indeed,phenotypic and anatomical analyses revealed that BnaA1.WRKY53 negatively regulated the leaf curling induced by leaf epinasty by suppressing the overexpansion of palisade cells under B deficiency.Further transcriptome enrichment analysis of differentially expressed genes(DEGs)between wild-type and BnaA1.WRKY53overexpression line showed auxin response pathway was enriched.In addition,Arabidopsis DR5::GFP auxin reporter line showed B deficiency caused predominant auxin signal accumulation in the adaxial side and concomitant adaxial cell expansion,which indicated that B deficiency may induce leaf curling by altering auxin distribution.Phytohormone quantification and gene expression analysis demonstrated that BnaA1.WRKY53 prevent auxin overaccumulation in leaves by suppressing auxin biosynthetic genes under B deficiency.Furthermore,exogenous 1-naphthlcetic acid(NAA)treatment experiments revealed that high auxin could induce leaf curling and BnaA1.WRKY53 expression.Overall,these findings demonstrate that auxin and the transcription factor BnaA1.WRKY53 synergistically regulate leaf curling to maintain an optimal leaf area under B deficiency,and provide novel insights into the resistance mechanisms against B-deficiency-induced leaf curling in oilseed rape. 展开更多
关键词 Brassica napus boron deficiency Leaf curling Leaf epinasty Adaxial side AUXIN WRKY
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Preparation and application of nano dendritic polyurethane for high-efficiency boron adsorption
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作者 Pengyu Sun Feiyu Gao +4 位作者 Wei Shi Hengyuan Zhang Shiao Du Wei Chen Meng Li 《Chinese Journal of Chemical Engineering》 2025年第6期209-221,共13页
Boron adsorbents with high adsorption capacities have long been a focus of research for a long time.This study used small molecular polyols with different hydroxyl groups as functional monomers and as end-capping agen... Boron adsorbents with high adsorption capacities have long been a focus of research for a long time.This study used small molecular polyols with different hydroxyl groups as functional monomers and as end-capping agents,functional dendritic polyurethanes with nano structure were successfully prepared by one-pot method.The single molecule size and surface morphology were characterized by dynamic light scattering,transmission electron microscopy and scanning electron microscopy,and the molecular size in the dry state was 11 to 18 nm.The prepared materials were used as the boron adsorbents,and the effects of pH,time,boron solution concentration and temperature on the adsorption were studied.The results showed that the capacity of adsorbed boron could reach 110-130 mg·g^(-1).Adsorption was a homogeneous monolayer adsorption controlled by chemisorption,and adsorption thermodynamics showed that was a spontaneous endothermic process.Adsorption behavior was best described by the pseudo-second-order kinetic model and the Langmuir isotherm.This study also showed that it was difficult for ortho/meta-hydroxyl groups to chelate with H_(3)BO_(3) and other polyborates,and the chelates mainly had good chelating properties with B(OH)_(4)^(-),and the chelates formed had large steric hindrance.At the same time,increasing the number of hydroxyl groups of functional monomers was beneficial to increase the adsorption capacity of materials.In addition,the cyclic adsorption/desorption experiments showed that DPUs have good cyclic stability.At the same time,the adsorption results of the original salt lake brine showed that other metal ions in the brine had little effect on the adsorption of boron,and the adsorption capacity was as high as52.93 mg·g^(-1),and the maximum adsorption capacity was obtained by Adams-Bohart model to58.80 mg·g^(-1).The outstanding selectivity and adsorption capacity of these materials have broad potential application,and are expected to be used for the efficient adsorption and removal in boroncontaining water bodies. 展开更多
关键词 boron ADSORBENT Dendritic polyurethane CHELATION
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Investigating the effect of NiO and NiF_(2)on boron carbide combustion
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作者 Siyi Zhang Yue Jiang +3 位作者 Dunhui Xu Jingxuan Li Changlu Zhao Lijun Yang 《Defence Technology(防务技术)》 2025年第10期60-70,共11页
Boron-based fuels,recognized for their high energy density and potential in energetic applications,encounter challenges such as long ignition delays and incomplete combustion,which result in reduced combustion efficie... Boron-based fuels,recognized for their high energy density and potential in energetic applications,encounter challenges such as long ignition delays and incomplete combustion,which result in reduced combustion efficiency and limited performance in aerospace propulsion.In this study,boron carbide(B4C)is investigated as an alternative fuel to pristine boron due to its favorable gas-phase combustion.Both metal oxide(nickel oxide(NiO))and metal fluoride(nickel fluoride(NiF_(2)))are selected as oxidizing modifiers to enhance the reactivity of B4C.A method combining laser ignition with optical diagnostics is employed to investigate the enhancing effects of different oxidizers on the ignition and combustion characteristics of B4C.Both NiO and NiF_(2)can significantly increase the combustion radiation intensity and reduce the time to maximum intensity of B4C.Differential scanning calorimetry,in-situ X-ray diffraction,and Fourier transform infrared spectroscopy were used for simultaneous thermal analysis of the B4C composite powders.Combined thermal analysis showed that the effects of NiO and NiF_(2)on promoting B4C combustion is mainly achieved via the formation of NimBn and the release of a large number of gas products.It is reasonable to speculate that the phase separation at the B2O3/NimBn interface forms new pathways for oxygen diffusion and reaction with the B core.The difference in the combustion mechanism of B4C with NiO and NiF_(2)lies in the gas phase products,i.e.,CO_(2)and BF3,respectively,thus leading to significant differences in their reaction processes. 展开更多
关键词 boron carbide THERMITE Metal fluoride Energetic materials Combustion mechanism
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