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Reaction Process of Chromium Slag Reduced by Industrial Waste in Solid Phase 被引量:7
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作者 SHI Yu-min DU Xing-hong +2 位作者 MENG Qing-jia SONG Shi-wei SUI Zhi-tong 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 2007年第1期12-15,共4页
M, a particular industrial waste, was selected to detoxify chromium slag at a high temperature. The carbon remaining in M reduced Cr ( Ⅳ ) of Na2 CrO4 borne in the chromium slag to Cr ( Ⅲ ) in the solid phase re... M, a particular industrial waste, was selected to detoxify chromium slag at a high temperature. The carbon remaining in M reduced Cr ( Ⅳ ) of Na2 CrO4 borne in the chromium slag to Cr ( Ⅲ ) in the solid phase reaction, and its thermodynamics and kinetics were studied. The reduction process of Na2CrO4 by carbon produced CO, whiCh'was endothermic. Under the experimental condition, the apparent activation energy was 4. 41 kJ·mol^-1 , the'apparent order of reaction for Na2 CrO4 was equal to one, and the partial pressure of CO was only 0.22 Pa at 1 330℃. 展开更多
关键词 chromium slag industrial waste reduction reaction solid phase reaction process
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FORMATION OF MANGANESE SILICIDE THIN FILMS BY SOLID PHASE REACTION 被引量:3
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作者 E. Q. Xie, W. W. Wang, N. Jiang and D. Y. He Department of Physics, Lanzhou University, Lanzhou 730000, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2002年第2期221-226,共6页
Manganese silicide MnSi_(2-x) thin films have been prepared on n-type siliconsubstrates through solid phase reaction. The heterostructures were analyzed by X-ray diffraction,Rutherford backscattering spectroscopy, Fou... Manganese silicide MnSi_(2-x) thin films have been prepared on n-type siliconsubstrates through solid phase reaction. The heterostructures were analyzed by X-ray diffraction,Rutherford backscattering spectroscopy, Fourier transform infrared transmittance spectroscopy andthe four-point probe technique. The results show that two manganese silicides have been formedsequentially via the reaction of thin layer Mn with Si substrate at different irradiation annealingstages, i.e., MnSi at 450 deg C and MnSi_(1.73) at 550 deg C. MnSi_(1.73) phase exhibits preferredgrowth after irradiation with infrared. In situ four-point probe measurements of sheet resistanceduring infrared irradiation annealing show that nucleation of MnSi and phase transformation of MnSito MaSi_(1.73) occur at 410 deg C and 530 deg C, respectively; the MnSi phase shows metallicbehavior, while MnSi_(1.73) exhibits semiconducting behavior. Characteristic phonon bands ofMnSi_(2-x) silicides, which can be used for phase identification along with conventional XRDtechniques, have been observed by FTIR spectroscopy. 展开更多
关键词 manganese silicide in situ sheet resistance solid phase reaction infrared spectra
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Acting mechanism of F,K,and Na in the solid phase sintering reaction of the Baiyunebo iron ore 被引量:2
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作者 Zhi-zhong Hao Sheng-li Wu +3 位作者 Yi-ci Wang Guo-ping Luo Hu-lin WU Xiang-guang Duan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2010年第2期137-142,共6页
The effect of F,K,and Na on the solid phase reaction of the Baiyunebo iron ore was investigated by differential thermal analysis (DTA) and X-ray diffraction(XRD).It has been identified that alkaline elements K and... The effect of F,K,and Na on the solid phase reaction of the Baiyunebo iron ore was investigated by differential thermal analysis (DTA) and X-ray diffraction(XRD).It has been identified that alkaline elements K and Na in the Baiyunebo ore instigate the formation of low melting point compounds Na2SiO3 and Na2O·Fe2O3 and the generation of molten state in the solid phase sintering.Element F in the Baiyunebo ore facilitates the formation of cuspidine compound 3CaO·2SiO2·CaF2 in the solid phase reaction.The cuspidine compound is kept in solid as one of the final products through the entire sintering process due to its high melting point.In the sintering process,CaF2and SiO2 react with CaO first and form 3CaO·2SiO2·CaF2 and 3CaO·2SiO2,so the formation of ferrites,Na2O·Fe2O3,and 2CaO·Fe2O3 is inhibited. 展开更多
关键词 iron ore solid phase sintering alkaline elements reaction temperature reaction product MECHANISM
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Thermal stability of Mg_2 Si epitaxial film formed on Si(111) substrate by solid phase reaction 被引量:2
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作者 王喜娜 王勇 +8 位作者 邹进 张天冲 梅增霞 郭阳 薛其坤 杜小龙 张晓娜 韩晓东 张泽 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期3079-3083,共5页
A single crystalline Mg2Si film was formed by solid phase reaction (SPR) of a Si(111) substrate with an Mg overlayer capped with an oxide layer(s),which was enhanced by post annealing from room temperature to 10... A single crystalline Mg2Si film was formed by solid phase reaction (SPR) of a Si(111) substrate with an Mg overlayer capped with an oxide layer(s),which was enhanced by post annealing from room temperature to 100℃ in a molecular beam epitaxy (MBE) system.The thermal stability of the Mg2Si film was then systematically investigated by post annealing in an oxygen-radical ambient at 300℃,450℃ and 650℃,respectively.The Mg2Si film stayed stable until the annealing temperature reached 450℃ then it transformed into amorphous MgOx attributed to the decomposition of Mg2Si and the oxidization of dissociated Mg. 展开更多
关键词 MG2SI solid phase reaction thermal stability
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Solid-phase Synthesis of PNA Monomer by Ugi Four-component Condensation Reaction 被引量:2
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作者 WenHaoWANG XiaoMinZOU XinZHANG YiQiuFU PingXU 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第5期585-588,共4页
关键词 Peptide nucleic acids (PNA) Ugi four-component condensation reaction (U-4CR) solid-phase synthesis Isocyanide.
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Effect of Annealing Temperature and Atmosphere to Surface Solid Phase Reaction of Sapphire Substrates and Spin-Coated Copper Nitrate Gel Films
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作者 Takashi Ehara 《Journal of Materials Science and Chemical Engineering》 2018年第5期1-10,共10页
The solid-phase reaction of sapphire (Al2O3) substrates and spin-coated copper nitrate films was studied. X-ray diffraction analysis revealed that a CuO fraction was observed by annealing at temperatures higher than ... The solid-phase reaction of sapphire (Al2O3) substrates and spin-coated copper nitrate films was studied. X-ray diffraction analysis revealed that a CuO fraction was observed by annealing at temperatures higher than 800℃. In addition, crystalline CuAlO2 was formed at annealing temperatures in the range of 900℃ – 1000℃ by solid-phase reaction of the spin-coated films and sapphire substrate. Crystalline CuAlO2 was formed by annealing at 1000℃ for 5 - 10 h, and CuAl2O4 was formed by annealing at 1000℃ for 15 h. When annealing under N2 flow, Cu2O was observed rather than CuAlO2. For a sample annealed in air at 1000℃ for 5 h, X-ray photoelectron spectroscopy measurements at various depths from surface revealed that Cu2+ ions are located around the surface, which suggests that the CuO fraction is present near the surface while the CuAlO2 fraction is located at greater depths from the surface of the samples. The depth profile of the sample suggests that there is no pure CuAlO2 layer in the sample, but that crystalline CuAlO2 is present in the sample as a mixture with CuO and Al2O3. 展开更多
关键词 solid-phase reaction Sapphire Substrate CuAlO2 CuO X-RAY Dif-fraction X-RAY PHOTOELECTRON Spectroscopy
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Solid Phase Synthesis of 1,4-Disubstituted 1,2,3-Triazole from Polystyrene-supported Selenium Resin
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作者 Wei Ming XU Lu Ling WU Xian HUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第5期603-605,共3页
We report here a solid-phase synthesis of 1, 4-disubstituted 1, 2, 3-triazole using polystyrene-supported selenium resin. The resin used here not only works as a simple linker, but also assists the crucial α-alkylati... We report here a solid-phase synthesis of 1, 4-disubstituted 1, 2, 3-triazole using polystyrene-supported selenium resin. The resin used here not only works as a simple linker, but also assists the crucial α-alkylation reaction and selenoxide syn-elimimation, which ensures the purity of the products. 展开更多
关键词 solid-phase synthesis 1 3-dipolar cycloaddition α-alkylation reaction 1 2 3-triazole.
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二硒化钴电催化剂的制备及氧还原性能测试 被引量:1
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作者 杨晓玲 孙怡然 +3 位作者 晁佳钰 支东彦 陈健壮 沈建华 《化学试剂》 CAS 2024年第1期53-58,共6页
具有高附加值的绿色环保型氧化剂——过氧化氢(H_(2)O_(2))的需求日益增加,急需发展绿色且安全的H_(2)O_(2)合成新方法。两电子氧还原反应(2e-ORR)是一种制备H_(2)O_(2)的高效方法,其中催化剂的高效率和高选择性是2e-ORR的关键。对二硒... 具有高附加值的绿色环保型氧化剂——过氧化氢(H_(2)O_(2))的需求日益增加,急需发展绿色且安全的H_(2)O_(2)合成新方法。两电子氧还原反应(2e-ORR)是一种制备H_(2)O_(2)的高效方法,其中催化剂的高效率和高选择性是2e-ORR的关键。对二硒化钴(CoSe_(2))电催化剂的制备和性能测试实验进行了探索。首先,通过联氨还原法制备钴纳米粒子;然后,通过简单的固相反应并在不同温度下退火制备CoSe_(2)电催化剂;最后,通过一系列的表征方法对CoSe_(2)电催化剂的表面形貌、晶型、电化学及其稳定性等进行了研究。为2e^(-)ORR电催化剂CoSe_(2)的进一步研究和应用开发提供借鉴。 展开更多
关键词 氧还原反应 过氧化氢 固相反应 CoSe_(2) 电催化剂
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Wittig反应实验的绿色化改进
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作者 刘宇芳 张彩红 袁茂森 《应用化学》 CAS CSCD 北大核心 2024年第4期586-592,共7页
传统的有机化学实验教学中,大多侧重实验技能的训练,设置实验内容时对实验安全性、经典性和可重复性等因素考虑较多,而对反应的绿色化、新方法和新技能等重视程度不够。为此,经典的有机反应也需要不断改进,本文将需要在大量有机溶剂中... 传统的有机化学实验教学中,大多侧重实验技能的训练,设置实验内容时对实验安全性、经典性和可重复性等因素考虑较多,而对反应的绿色化、新方法和新技能等重视程度不够。为此,经典的有机反应也需要不断改进,本文将需要在大量有机溶剂中进行的传统Wittig反应改进为无溶剂的固相研磨反应,使得合成方法更加简单、绿色、安全和高效。设计合成了3个不同推拉型(D-π-A)二苯乙烯结构分子,优化了反应条件,测定了它们的光谱性质,并对其进行比较,讨论其构性关系,不仅引入绿色化学理念,而且对知识进行扩展,增加了实验的新颖性、探索性和趣味性,提升了学生创新能力。 展开更多
关键词 绿色化学 WITTIG反应 固相研磨合成 构性分析 基础有机化学实验
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天然石膏制备烧石膏晶须试验研究
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作者 陈秋菊 姚金 +2 位作者 丁文金 孙红娟 彭同江 《化工矿物与加工》 CAS 2024年第4期1-7,共7页
基于我国天然石膏资源丰富、但产品附加值低的现状,根据溶解-再结晶理论,以天然石膏为原料、硝酸为助剂,采用常压酸化法开展了高附加值烧石膏晶须制备试验研究,考查了固液比、硝酸浓度和反应温度对所得产物物相与显微形貌的影响。研究... 基于我国天然石膏资源丰富、但产品附加值低的现状,根据溶解-再结晶理论,以天然石膏为原料、硝酸为助剂,采用常压酸化法开展了高附加值烧石膏晶须制备试验研究,考查了固液比、硝酸浓度和反应温度对所得产物物相与显微形貌的影响。研究结果表明:样品中烧石膏晶须的质量分数随着硝酸浓度和反应温度的升高而升高,样品中晶须的质量分数随着固液比的增大呈先升高后降低的趋势;优化条件下所得样品的物相主要为烧石膏相,另有极少量的石膏相和硬石膏相,样品中晶须的长度为509~650μm,长径比为43~62。研究成果可为天然石膏的高值化利用提供参考。 展开更多
关键词 天然石膏 烧石膏 晶须 硝酸 物相 形貌 固液比 反应温度
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铪钛酸钡陶瓷制备及其压电性能的微观机制研究
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作者 李雄伟 尹红梅 +2 位作者 周恒为 赵兴宇 黄以能 《电子元件与材料》 CAS 北大核心 2024年第3期277-283,共7页
采用传统固相反应法制备系列BaHf_(x)Ti_(1-x)O_(3)陶瓷,通过对陶瓷的压电、铁电、相组成、晶粒尺寸的测试和分析,发现:所有BaHf_(x)Ti_(1-x)O_(3)陶瓷样品均具有纯钙钛矿结构,室温均为铁电体具有压电性;在x<0.1时室温压电系数为195~... 采用传统固相反应法制备系列BaHf_(x)Ti_(1-x)O_(3)陶瓷,通过对陶瓷的压电、铁电、相组成、晶粒尺寸的测试和分析,发现:所有BaHf_(x)Ti_(1-x)O_(3)陶瓷样品均具有纯钙钛矿结构,室温均为铁电体具有压电性;在x<0.1时室温压电系数为195~327p C/N,x=0.02时,压电系数、剩余极化强度和平均晶粒尺寸最大,分别为327pC/N,13.3μC/cm^(2)和37.2μm,大晶粒尺寸和四方-正交-三方多相共存是其具有大压电系数的主要原因。 展开更多
关键词 铪钛酸钡 固相反应 微观机制 压电系数
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气固两相介质协同抑制瓦斯爆炸实验及分子动力学研究
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作者 谯永刚 华杰 +2 位作者 袁丹萍 张泽宇 左文哲 《爆炸与冲击》 EI CAS CSCD 北大核心 2024年第5期167-178,共12页
针对传统单相抑爆介质效果不佳的问题,提出气固两相介质通过不同抑爆原理的协同作用,实现高效快速抑制瓦斯爆炸。研究使用NaHCO3粉体与CO_(2)气体协同抑制瓦斯爆炸的方法,选用标准20 L球形爆炸测试装置,并通过密度泛函理论对甲烷爆炸微... 针对传统单相抑爆介质效果不佳的问题,提出气固两相介质通过不同抑爆原理的协同作用,实现高效快速抑制瓦斯爆炸。研究使用NaHCO3粉体与CO_(2)气体协同抑制瓦斯爆炸的方法,选用标准20 L球形爆炸测试装置,并通过密度泛函理论对甲烷爆炸微观反应机理中各反应物、过渡态、产物进行构型优化,在此基础上进行后续计算。结果表明:体积分数为16%的CO_(2)和质量浓度为0.35 g/L的NaHCO3单相介质对瓦斯爆炸具有优良的抑制效果,但0.1 g/L粉体存在时会使最大升压速率提升17.9%;气固两相介质抑爆相较单相CO_(2)、单相NaHCO3粉体使最大爆炸压力降低,采用体积分数为8%的CO_(2)协同0.125 g/L粉体时,瓦斯爆炸最大爆炸压力降低72.42%,最大升压速率降至2.345 MPa/s,抑制效果达到最优;但当体积分数为4%的CO_(2)协同0.05 g/L粉体时会使最大爆炸升压速率上升93.68%,反应呈现出一定的加剧现象;量子化学计算表明,在气固两相介质协同抑制瓦斯爆炸的过程中,NaHCO3粉体裂解会吸收反应体系中的热量,其分解产物会与混合体系中的OH·、H·优先反应,阻碍O·的产生,将链式过程抑制在CH2O阶段,进而抑制链式反应的传递过程;NaHCO3粉体分解产生的CO_(2)与混合体系中的CO_(2)稀释了混合体系中甲烷的体积分数,减少甲烷与氧气分子之间碰撞发生的概率,对反应进程起到有效抑制作用。 展开更多
关键词 抑制瓦斯爆炸 气固两相介质协同 反应机理 混合体系 吸热 分子动力学
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温度在四氧化三钴制备中的影响分析
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作者 辛勇诚 《化工管理》 2024年第20期139-141,149,共4页
温度在四氧化三钴生产中是一个重要的控制因素,不稳定会导致粉末指标大的波动。采用两种温度工艺合成球形碳酸钴,利用XRD和TEM分析其生长机理,不同温度下呈现不同的优势生长面,高温下为多晶结构,低温单晶,通过SEM看高温碳酸钴表面颗粒... 温度在四氧化三钴生产中是一个重要的控制因素,不稳定会导致粉末指标大的波动。采用两种温度工艺合成球形碳酸钴,利用XRD和TEM分析其生长机理,不同温度下呈现不同的优势生长面,高温下为多晶结构,低温单晶,通过SEM看高温碳酸钴表面颗粒呈棒状,低温为细颗粒堆叠。以低温合成的球形碳酸钴为原料,采用高温煅烧方法,制备球形四氧化三钴。系统研究了不同温度和不同升温速率下热性能、粒径、物相的变化。通过这些条件实验揭示了改变温度条件及不同升温速率下碳酸钴的生长规律及其内在分解原理。 展开更多
关键词 烧结 碳酸钴合成 四氧化三钴 固相反应 烧结机理
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Phase Transformation of Nanosized Zirconia 被引量:1
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作者 刘欣梅 阎子峰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第4期424-432,共9页
The nanosized zirconia was synthesized via solid state reaction in the presence of surfactant. The results indicate that crystal phase of zirconia can be controlled by tuning the synthesis parameters such as OH^-/Zr m... The nanosized zirconia was synthesized via solid state reaction in the presence of surfactant. The results indicate that crystal phase of zirconia can be controlled by tuning the synthesis parameters such as OH^-/Zr molar ratio, crystallizing temperature and time. It can be transformed among amorphous, tetragonal and monoclinic phases. The transformation is driven by particle size. The research shows the nanocrystalline zirconia possesses the higher thermal stability compared with amorphous framework. The "glow exotherm" can be observed for the amorphous samples. Otherwise, it is in the absence for nanocrystalline samples. Herein, the reason for retention of tetragonal zirconia is demonstrated. 展开更多
关键词 solid state reaction ZIRCONIA NANOSIZE phase transformation
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Reduction reaction in Al-CuO powder mixturedriven by mechanical alloying
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作者 吴进明 郑史烈 +1 位作者 李志章 吴年强 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第4期717-722,共6页
The solid state reduction reaction of Al-10 % CuO mixed powders during mechanical alloying was investigated using XRD, DTA and TEM. The CuO is believed to be gradually reduced by Al, and controlled by diffusion of ato... The solid state reduction reaction of Al-10 % CuO mixed powders during mechanical alloying was investigated using XRD, DTA and TEM. The CuO is believed to be gradually reduced by Al, and controlled by diffusion of atoms and ions. Reduced Cu spontaneously reacts with Al to form a metastable equilibrium of Al (Cu) with Al4Cu9 phase during ball-milling, instead of CuAl2 and Al(Cu), which is only observed after annealing. 展开更多
关键词 solid state reaction mechanical ALLOYING phase TRANSFORMATION
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Solid state synthesis and characterization of iron(Ⅱ) pyrophosphate Fe_2P_2O_7
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作者 Zheng Wei Xiao Guo Rong Hu Zhong Dong Peng Ke Du Xu Guang Gao 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第12期1525-1527,共3页
Offwhite pure Fe2P207 was synthesized through solid phase reaction using Fe203 and NH4H2PO4 in argon atmosphere. The reaction products of Fe203 and NHaH2PO4 at a series of temperatures from 400 to 900 ℃ were characte... Offwhite pure Fe2P207 was synthesized through solid phase reaction using Fe203 and NH4H2PO4 in argon atmosphere. The reaction products of Fe203 and NHaH2PO4 at a series of temperatures from 400 to 900 ℃ were characterized by XRD. Comparison and analysis of XRD patterns of resultant products indicated well-crystallized Fe2P207 could be obtained over 630 ℃ and Fe2P207 prepared at 700 ℃ was triclinic in cell type. Comparison of the cell parameters proved that the as-prepared Fe2P207 belonged to β- Fe2P207 in crystal phase and SEM showed its size distribution was 0.5-2 μm. 展开更多
关键词 PREPARATION solid phase reaction CHARACTERIZATION
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基于EMMS-1M曳力模型的空气反应器气固流动及化学反应特性数值分析
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作者 李慧君 王业库 +1 位作者 鲁许鳌 张久意 《动力工程学报》 CAS CSCD 北大核心 2023年第7期815-822,834,共9页
针对传统曳力模型难以准确预测气固相间曳力的问题,考虑到计算精度和模型通用性,选用经过介尺度修正的EMMS-1M曳力模型耦合双流体模型,模拟了颗粒直径和进口气速对空气反应器冷态流化和热态化学反应的影响。结果表明:颗粒直径减小和进... 针对传统曳力模型难以准确预测气固相间曳力的问题,考虑到计算精度和模型通用性,选用经过介尺度修正的EMMS-1M曳力模型耦合双流体模型,模拟了颗粒直径和进口气速对空气反应器冷态流化和热态化学反应的影响。结果表明:颗粒直径减小和进口气速增加,使床层气体压力分布更加均匀,床层轴向颗粒体积分数降低,床层颗粒返混现象减弱,颗粒轴向速度增加,温度升高促进反应正向进行,氧气转化率升高;进口气速增加,使颗粒在床层分布均匀,气固混合彻底,促进了化学反应,但进口气速过高,会携带出大量的颗粒,且在床层的停留时间减少,不利于气固化学反应的发生。 展开更多
关键词 气固两相流 化学反应 介尺度 数值模拟
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Spontaneous Changes of Solid 5,7-di-<i>tert</i>-butylspiro(2,5)octa-4,7-diene-6-one in Storage Conditions at Room Temperature
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作者 Alexandre A. Volodkin Gennady E. Zaikov +3 位作者 Lydia N. Kurkovskaja Sergey M. Lomakin Irina M. Levina Elena V. Koverzanova 《Advances in Chemical Engineering and Science》 2015年第3期299-304,共6页
On an example of spontaneous changes 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one at room temperature, a new example of condensations in a solid station is opened. The single crystal of 2-(3’, 5'-di-tert-but... On an example of spontaneous changes 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one at room temperature, a new example of condensations in a solid station is opened. The single crystal of 2-(3’, 5'-di-tert-butyl-4'-hydroxy-phenyl)-ethyloxy-p-cresole is produced as result of a structure transformation 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one in a solid phase at room temperature except a single crystal at transformation 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one a new substance is formed too. Spectrums 1Н and 13С NMR differ from similar spectrums of initial compound and the single crystal. New substance represents an admixture of isomeric compounds, capable reversible to be transformed in initial 5,7-di-tert-butylspiro(2,5) octa-4,7-diene-6-one and 2-(3’, 5'-di-tert-butyl-4'-hydroxyphenyl)-ethyloxy-p-cresole. 展开更多
关键词 solid-phase reactions 5 7-Di-tert-butylspiro(2 5)octa-4 7-diene-6-one 2-(3’ 5'-di-tert-butyl-4'-hydroxyphenyl)-ethyloxy-p-cresole NMR and IR Spectroscopy
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一步固相反应制备铝改性活性炭对矿井水中氟化物的超快去除 被引量:1
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作者 齐永辉 包一翔 +9 位作者 李俏 王蕾 李井峰 张海琴 吴敏 陈静允 钟金魁 郭强 蒋斌斌 李海祥 《煤炭科学技术》 EI CAS CSCD 北大核心 2023年第S01期461-469,共9页
矿井水中(F^(−))超标已成为制约我国西部矿区煤炭绿色开发的主要挑战之一。针对该问题,开发了机械化学法一步固相反应制备Al改性活性炭(AC-Al)的方法,解决了常规水热法改性活性炭产生废液废渣、制备周期长的问题,并实现了矿井水中F^(−)... 矿井水中(F^(−))超标已成为制约我国西部矿区煤炭绿色开发的主要挑战之一。针对该问题,开发了机械化学法一步固相反应制备Al改性活性炭(AC-Al)的方法,解决了常规水热法改性活性炭产生废液废渣、制备周期长的问题,并实现了矿井水中F^(−)的快速、高效去除。研究了Al添加量、pH、共存阴离子和有机物、吸附剂投加量及反应时间等对除氟性能的影响。AC-Al除氟性能与Al添加量成正比,添加量为0.32 g,吸附反应30 s时,水中F^(−)去除率达到80%以上。pH在3~10范围内,F^(−)去除率均大于80%,具有良好的水质适应性。吸附过程更符合Langmuir模型,即为单层吸附,理论饱和吸附量为1.47 mg/g。吸附过程符合准一级动力学模型。硫酸根离子、氯离子和碳酸氢根离子(1000 mg/L时)、腐殖酸对F^(−)去除没有影响,氯离子和碳酸氢根离子质量浓度为3000 mg/L时,除氟率分别降低约21%和11%。AC-Al投加量为10 g/L时,矿井水中F^(−)去除率达84.9%(30 s内),质量浓度从4.85 mg/L降低至0.73 mg/L,满足《地表水环境质量标准》(GB3838—2002)中F^(−)浓度限值(I、II、III类),矿井水中F^(−)吸附过程同样符合准一级动力学模型。元素面分布表明,Al均匀地负载于活性炭表面;F^(−)均匀吸附在AC-Al上,与Al分布特征相似,证明Al是F^(−)吸附潜在活性位点。X射线光电子能谱结果表明,F^(−)吸附前后,AC-Al表面的Al元素结合能从74.20 eV升高至74.28、77.80 eV等2种状态,说明Al与F结合形成了Al-FOH、Al-F化学键,是快速稳定除氟的直接原因。同时,AC-Al吸附剂上的Al溶出量很低(0.34μg/g)。机械化学法制备的Al改性活性炭除氟效果良好,可为除氟吸附剂制备提供新的普适性技术路径,同时为解决矿井水除氟问题提供技术支撑。 展开更多
关键词 矿井水 吸附除氟 固相反应 活性炭 铝改性
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室温固相法制备硼化铁及电催化分解水产氢性能 被引量:1
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作者 刘紫城 童瑞杰 +1 位作者 李越湘 彭绍琴 《南昌大学学报(理科版)》 CAS 北大核心 2023年第2期134-140,147,共8页
采用室温固相反应和煅烧后处理相结合的方法,成功合成了高活性的硼化铁析氢催化剂。通过扫描电子显微镜(SEM)、X射线衍射仪(XRD)、X射线光电子能谱仪(XPS)、电感耦合等离子发射光谱仪(ICP)等技术表征了硼化铁催化剂的组成、结构和形貌... 采用室温固相反应和煅烧后处理相结合的方法,成功合成了高活性的硼化铁析氢催化剂。通过扫描电子显微镜(SEM)、X射线衍射仪(XRD)、X射线光电子能谱仪(XPS)、电感耦合等离子发射光谱仪(ICP)等技术表征了硼化铁催化剂的组成、结构和形貌。和传统的溶液法制备的硼化铁相比,室温固相法制备出的硼化铁表现出更加优异的析氢性能,在碱性电解质溶液中,在100 mA·cm^(-2)的电流密度下,固相法制备的硼化铁的HER过电位为303 mV,塔菲尔斜率为65 mV·dec^(-1),分别低于溶液法制备的硼化铁的402 mV和80 mV·dec^(-1)。其原因是固相法制备的硼化铁含有比溶液法制备的硼化铁更高的硼含量、更好的导电性。室温固相法制备硼化铁消耗的硼氢化钠要远小于溶液法,且大大减少废水排放,有利于降低制备成本和环境保护,有良好的应用前景。 展开更多
关键词 电催化分解水 析氢反应 过渡金属硼化物 硼化铁 室温固相反应
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