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Preparation of α-Bi_2O_3 from bismuth powders through low-temperature oxidation 被引量:4
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作者 夏纪勇 唐谟堂 +2 位作者 陈萃 金胜明 陈永明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第9期2289-2294,共6页
α-Bi2O3 powders were prepared from nanometer Bi powders through low-temperature oxidation at less than 873.15 K. XRD, SEM, TEM and HRTEM were used to characterize the structure and morphology of Bi powders and Bi2O3 ... α-Bi2O3 powders were prepared from nanometer Bi powders through low-temperature oxidation at less than 873.15 K. XRD, SEM, TEM and HRTEM were used to characterize the structure and morphology of Bi powders and Bi2O3 particles. Kinetic studies on the bismuth oxidation at low-temperatures were carried out by TGA method. The results show that bismuth beads should be reunited and oxidized to become irregular Bi2O3 powders. The bismuth oxidation follows shrinking core model, and its controlling mechanism varies at different reaction time. Within 0-10 min, the kinetics is controlled by chemical reaction, after that it is controlled by O2 diffusion in the solid α-Bi2O3 layer. The apparent activation energy is determined as 55.19 kJ/mol in liquid-phase oxidation. 展开更多
关键词 bismuth powder low-temperature oxidation α-Bi2O3 oxidation kinetics
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Synthesis of La_(0.9)Sr_(0.1)Ga_(0.8)Mg_(0.2)O_(3-δ) Powder for Solid Oxide Fuel Cell by a Nitrate-Citrate Combustion Route 被引量:2
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作者 Naiqing ZHANG, Kening SUN, Derui ZHOU and Ningning WUHarbin Institute of Technology, Harbin 150001, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第6期791-793,共3页
A nitrate-citrate combustion route to synthesize La0.9Sr0.1Ga0.8Mg0.2O3-σ powder for solid oxide fuel cell application was presented. This route is based on the gelling of nitrate solutions by the addition of citric ... A nitrate-citrate combustion route to synthesize La0.9Sr0.1Ga0.8Mg0.2O3-σ powder for solid oxide fuel cell application was presented. This route is based on the gelling of nitrate solutions by the addition of citric acid and ammonium hydroxide, followed by an intense combustion process due to an exothermic redox reaction between nitrate and citrate ions. The optimum technical parameters are that the pH value is 5, and the molar ratio of citric acid to the total metallic ion is 1.5:1. X-ray diffraction characterization of calcined gel shows that pure phase was synthesized after calcination at 1400℃for 10 h, and the TEM result shovvs the calcined powder with average particle size is about 150 nm. The grain resistance contributes to the total resistance of sintered peliet below 500℃. The conductivity of the sintered peliet at 800℃ was 0.07 S-1·cm-1 higher than the conductivity of YSZ (0.05 S-1·cm-1 at 800℃) 展开更多
关键词 La_(0.9)Sr_(0.1)Ga_(0.8)Mg_(0.2)O_(3-δ)powder Gel-combustion synthesis Solid oxide fuel cell
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Triboluminescent Complexes of Rare Earth Ⅱ.Mixed-ligand Complexes of Eu^(3+) with Thenoyltrifluoroacetone and Pyridine-N-Oxide or its Substitutive Derivatives
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作者 朱文祥 花文滨 《Journal of Rare Earths》 SCIE EI CAS CSCD 1991年第1期27-30,共4页
Five triboluminescent mixed-ligand complexes of Eu^(3+)with thenoyltrifluoroacetone(TTA)and pyridine-N-oxide or its substitutive derivatives have been prepared.They are all pale yellow crystalline com- pounds with the... Five triboluminescent mixed-ligand complexes of Eu^(3+)with thenoyltrifluoroacetone(TTA)and pyridine-N-oxide or its substitutive derivatives have been prepared.They are all pale yellow crystalline com- pounds with the formula of Eu(TTA)_3·L(L=py NO.2-pie NO,3-pie NO,4-pic NO,bipy N_2O_2).Their physico-chemical properties have been studied with conductometry,UV and IR absorption and fluorescence spectroscopy.Once the complexes are touched or rubbed by a glass rod,they emit strong red triboluminescent light which is similar to the characteristic fluorescence of Eu^(3+). 展开更多
关键词 Triboluminescent complexes MIXED-LIGAND eu^(3+) TTA Pyridme-N-oxide
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Synthesis, Characterization and Properties of N,N′-Bis(6-methyl-2-pyridine-N-oxide)-1,3-Propane and Europium and Terbium Complexes
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作者 苟如虎 李岗 +2 位作者 刘波 杨汝栋 闫兰 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第S1期21-24,共4页
A new ligand, N,N′-Bis(6-methyl-2-pyridine-N-oxide)-1,3-propane (L), and some binary lanthanide complexes (Ln=Eu^(3+), Tb^(3+)) were synthesized and characterized in detail. The composition of the binary complexes wa... A new ligand, N,N′-Bis(6-methyl-2-pyridine-N-oxide)-1,3-propane (L), and some binary lanthanide complexes (Ln=Eu^(3+), Tb^(3+)) were synthesized and characterized in detail. The composition of the binary complexes was determined as LnL(NO_3)_3. They are 1∶1 electrolytes in DMF. The complexes have strong characteristic line fluorescence emission spectra, and it is also found that TbL(NO_3)_3 complex has stronger luminescence intensity than EuL(NO_3)_3 in solid state and in methanol. 展开更多
关键词 methylpicolinic acid N-oxide binary complex eu^(3+) and Tb^(3+) complexes rare earths
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A New Combustion Process for Nanosized BaCe_(0.95)Y_(0.05)O_(3-δ) Powders 被引量:1
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作者 孟波 谭小耀 +1 位作者 张宝砚 杨乃涛 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第5期658-662,共5页
Nanosized BaCe_(0.95)Y_(0.05)O_(3-δ) powders with the homogeneous composition were synthesized by a new combustion process based on the Pechini method. A polymeric precursor sol was formed by use of citric acid and e... Nanosized BaCe_(0.95)Y_(0.05)O_(3-δ) powders with the homogeneous composition were synthesized by a new combustion process based on the Pechini method. A polymeric precursor sol was formed by use of citric acid and ethylene glycol as the chelating agents of metal ions. The perovskite-type BaCe_(0.95)Y_(0.05)O_(3-δ) powders with uniform shape and smaller than 40 nm in sized were obtained through the combustion of the polymeric precursor sol at the existence of nitric acid and ammonium hydroxide. It was found the particle size could be controlled by modulating the quantities of nitric acid and ammonium hydroxide, the quantities of the residue, carbonate ions were also affected by the quantities of the citric acid and ethylene glycol. 展开更多
关键词 inorganic nonmetallic materials nanosized powder perovskite-type oxides BaCe_(0.95)Y_(0.05)O_(3-δ) combustion synthesis rare earths
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Effect of micro-Al_(2)O_(3) powders on oxidation and corrosion behaviors of low-carbon MgO-C refractories
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作者 Yang Chen Zeng-yi Li +4 位作者 Hao-bo Tan Yu-ran Fu Jun Ding Cheng-ji Deng Chao Yu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2024年第6期1522-1534,共13页
To solve the problem of poor high-temperature service performance caused by low carbonization of MgO-C refractories,low-carbon MgO–C refractories with excellent thermal shock,oxidation and corrosion resistances were ... To solve the problem of poor high-temperature service performance caused by low carbonization of MgO-C refractories,low-carbon MgO–C refractories with excellent thermal shock,oxidation and corrosion resistances were successfully designed by using SiC whiskers as reinforcing phases and introducing micro-Al_(2)O_(3) powders as additives.The results indicated that the addition of micro-Al_(2)O_(3) powders optimized the internal structure of the material,like the columnar β-Si_(3)N_(4) with a stepped distribution and the mosaic structure formed between granular and flaky Mg_(2)SiO_(4),which synergistically strengthened and toughened the material and gave the material excellent mechanical properties and thermal shock resistance.Specifically,the cold modulus of rupture and cold crushing strength after thermal shock were increased by 4.1 and 20.3 MPa,respectively.Moreover,the addition of micro-Al_(2)O_(3) powders promoted the formation of fine particles of Mg_(2)SiO_(4),MgAl_(2)O_(4) and MgO,as well as a dense protective layer of Mg_(2)SiO_(4) in the material under high-temperature environment.Furthermore,spinel and high-temperature solid solution were formed in the corrosion environment.The oxidation and corrosion resistances were greatly improved by 41%and 15%,respectively. 展开更多
关键词 Low-carbon MgO-C refractory oxidation resistance Corrosion resistance Thermal shock resistance Micro-Al_(2)O_(3)powder
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Catalytic Performance for Oxidative Coupling of Methane over Eu_2O_3 Catalysts Promoted by Alkaline Earth Flourides
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作者 龙瑞强 万惠霖 《Journal of Rare Earths》 SCIE EI CAS CSCD 1997年第4期22-26,共5页
The catalytic performance of oxidative coupling of methane(OCM) over Eu 2O 3 catalysts promoted by alkaline earth fluorides was studied The results showed that C 2 hydrocarbon selectivity and yield over the fluor... The catalytic performance of oxidative coupling of methane(OCM) over Eu 2O 3 catalysts promoted by alkaline earth fluorides was studied The results showed that C 2 hydrocarbon selectivity and yield over the fluoride promoted Eu 2O 3 catalysts were apparently higher than those over pure Eu 2O 3; the OCM performance increased according to the sequence of CaF 2 Eu 2O 3≈BaF 2 Eu 2O 3<SrF 2 Eu 2O 3 under the same conditions XRD experiment indicated that rhombohedral EuOF phase formed in the fresh BaF 2 Eu 2O 3 catalyst, while the exchange of F - and O 2- did not apparently happen in the fresh CaF 2 Eu 2O 3 and SrF 2 Eu 2O 3 catalysts Pyridine TPD and CO 2 TPD measurements found that, after adding SrF 2 to Eu 2O 3, the catalyst surface acidity decreased, whereas the surface basic strength increased slightly, resulting in an improvement in C 2 selectivity and yield 展开更多
关键词 Rare earths oxidative coupling of methane eu 2O 3 Alkaline earth fluoride
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Relationship between powder characteristic and internal oxidation of Al in Cu-Al pre-alloyed powders
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作者 Shuhua LIANG Xianhui WANG +1 位作者 Liang FANG Zhikang FAN 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2009年第1期71-80,共10页
Since Cu-Al powder characteristics have important effects on the preparation of Cu/Al2O3 composite, the apparent activation energy of Al internal oxidation reaction in Cu-Al pre-alloyed powders with different characte... Since Cu-Al powder characteristics have important effects on the preparation of Cu/Al2O3 composite, the apparent activation energy of Al internal oxidation reaction in Cu-Al pre-alloyed powders with different characteristics was calculated in the present investigation. The microstructure and properties of the synthesized Cu/Al2O3 were studied. The results show that high-energy milling can obviously promote internal oxidation of Al in Cu-Al powders in the same solid solubility. At the same milling conditions and internal oxidation parameters, the solid solution of Al in Cu either in low or high amount will result in the poor microstructure and properties of the Cu/Al2O3 composite. Subsequently, when high-energy milling and internal oxidation are synchronously used to prepare the Cu/Al2O3 composite, there should be an appropriate solubility and milling effect for the pre-alloyed powders. 展开更多
关键词 powder characteristic Internal oxidation Cu/Al2O3 composite material Solid solution Reaction rate
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Ce^(3+)和Y^(3+)掺杂对Ca_2MgSi_2O_7:Eu^(2+)荧光粉发光性能的影响 被引量:4
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作者 章少华 胡江峰 +1 位作者 王建军 谢冰 《材料导报》 EI CAS CSCD 北大核心 2010年第6期8-10,共3页
在还原气氛下,采用高温固相法合成了Ca2MgSi2O7:Eu2+,R3+(R3+=Ce3+,Y3+)系列荧光粉。结果表明,少量稀土离子的掺入没有改变晶体的物相结构。在Ca2MgSi2O7:Eu2+荧光粉中,Ce3+和Y3+的掺入对荧光强度的影响较大,且与掺杂元素、掺杂量相关... 在还原气氛下,采用高温固相法合成了Ca2MgSi2O7:Eu2+,R3+(R3+=Ce3+,Y3+)系列荧光粉。结果表明,少量稀土离子的掺入没有改变晶体的物相结构。在Ca2MgSi2O7:Eu2+荧光粉中,Ce3+和Y3+的掺入对荧光强度的影响较大,且与掺杂元素、掺杂量相关。当掺杂Ce3+和Y3+的量分别为0.007mol和0.05mol时,所得荧光粉在532nm处的发光强度分别是未掺杂时的127%和117%。结果表明,在Ca2MgSi2O7中Ce3+与Eu2+存在能量传递,Ce3+的加入显著敏化了Eu2+的发光,导致荧光强度的进一步提高;Y3+的掺杂可以使荧光粉的粒径减小,并导致基质中的电荷缺陷而敏化Eu2+发光,从而使荧光强度进一步提高。 展开更多
关键词 荧光粉 Ca_2MgSi_2O_7:eu^2+ CE^3+ Y^3+ 发光性能
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CaSiO_3∶Eu^(3+)荧光粉的合成及光谱性质 被引量:2
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作者 邓岳锋 甘树才 +1 位作者 宋艳华 曹林 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2005年第2期225-227,共3页
利用高温固相法合成了CaSiO3∶Eu3+荧光粉,确定其最佳的合成条件为:烧结温度1200℃;烧结时间3h;助熔剂用量3%;激活剂的配比为2%(摩尔分数).对合成样品进行了荧光光谱分析,结果表明,该荧光粉的光谱中609nm处出现很强的发射峰,归属为Eu3+... 利用高温固相法合成了CaSiO3∶Eu3+荧光粉,确定其最佳的合成条件为:烧结温度1200℃;烧结时间3h;助熔剂用量3%;激活剂的配比为2%(摩尔分数).对合成样品进行了荧光光谱分析,结果表明,该荧光粉的光谱中609nm处出现很强的发射峰,归属为Eu3+的5D0→7F2跃迁发射. 展开更多
关键词 荧光粉 偏硅酸钙 eu^3+ 光谱性质
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溶胶-凝胶法制备超细Y_2O_3: Eu^(3+) 被引量:6
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作者 周建国 姜伟 +3 位作者 赵凤英 安英格 刘欣凤 阮慎康 《河南师范大学学报(自然科学版)》 CAS CSCD 1998年第2期105-108,共4页
以金属醇盐为原料,采用溶胶-凝胶法制备出均匀的、体心立方结构的Y2O3Eu3+超细粉末.借助TG-DTA、IR、XRD和SEM等分析手段,研究了凝胶的转变过程和粉末的结构,观察了粉末的形貌和粒径.结果表明:在423℃... 以金属醇盐为原料,采用溶胶-凝胶法制备出均匀的、体心立方结构的Y2O3Eu3+超细粉末.借助TG-DTA、IR、XRD和SEM等分析手段,研究了凝胶的转变过程和粉末的结构,观察了粉末的形貌和粒径.结果表明:在423℃煅烧已有Y2O3Eu3+相生成,经850℃煅烧即得单-Y2O3Eu3+相超微粉,平均晶粒尺寸为53nm;煅烧温度进一步升高。 展开更多
关键词 溶胶-凝胶法 氧化钇 超细粉末
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Eu^(3+)掺杂二氧化钛纳米粉末的制备及发光性质研究 被引量:3
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作者 刘国敬 胡晓云 +3 位作者 潘静 张德恺 韩永举 叶岩溪 《菏泽学院学报》 2009年第5期70-74,共5页
以钛酸四丁酯为前驱物,利用溶胶-凝胶法制备了Eu3+掺杂TiO2纳米粉末.首先对纳米粉末的发光性质进行了一定的研究,找出了纳米晶发光效率最佳激发波长,然后用最佳激发波长对不同退火温度下摩尔分数为0.5%Eu3+离子掺杂TiO2纳米晶和同一退... 以钛酸四丁酯为前驱物,利用溶胶-凝胶法制备了Eu3+掺杂TiO2纳米粉末.首先对纳米粉末的发光性质进行了一定的研究,找出了纳米晶发光效率最佳激发波长,然后用最佳激发波长对不同退火温度下摩尔分数为0.5%Eu3+离子掺杂TiO2纳米晶和同一退火温度下不同摩尔分数Eu3+离子掺杂的纳米晶进行激发,对发射光谱进行分析,从而得到制备纳米晶的最佳退火温度和最佳Eu3+离子掺杂的摩尔分数. 展开更多
关键词 eu3+掺杂TiO2 纳米粉末 制备 发光性质
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碱土金属氟化物促进Eu_2O_3催化剂的甲烷氧化偶联性能 被引量:1
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作者 龙瑞强 陈明树 +1 位作者 卢维奇 万惠霖 《中国稀土学报》 CAS CSCD 北大核心 1997年第3期197-201,共5页
考察了碱土金属氟化物促进的Eu2O3在甲烷氧化偶联反应中的催化性能。发现在Eu2O3中添加碱土金属氟化物后,碳二烃(C2)的选择性和收率都有明显提高。当Eu2O3摩尔含量相同时,催化性能按CaF2Eu2O3≈BaF... 考察了碱土金属氟化物促进的Eu2O3在甲烷氧化偶联反应中的催化性能。发现在Eu2O3中添加碱土金属氟化物后,碳二烃(C2)的选择性和收率都有明显提高。当Eu2O3摩尔含量相同时,催化性能按CaF2Eu2O3≈BaF2Eu2O3<SrF2Eu2O3顺序递增。XRD分析结果表明,在新鲜的BaF2Eu2O3催化剂中出现了菱形EuOF新相,而在其它两类催化剂中氟氧离子交换不明显,这种差异与碱土金属氟化物中阳离子半径的差别有关。吡啶(Py)和CO2TPD测试表明,Eu2O3中添加SrF2后,表面酸性减弱,碱强度稍有增加,有利于C2选择性的提高。 展开更多
关键词 甲烷氧化偶联 碱土金属 氟化物 催化剂 氧化铕
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铝阳极氧化多孔膜制备及Eu^(3+)组装 被引量:1
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作者 阳福 刘应亮 《发光学报》 EI CAS CSCD 北大核心 2005年第2期233-236,共4页
在草酸体系中,采用二次阳极氧化法可制备大面积有序铝阳极氧化多孔膜(AAO),用X射线粉末衍射(XRD)仪进行物相分析,利用扫描电子显微镜(SEM)表征多孔膜的形貌。研究表明,低温条件下制备的多孔膜孔径大小分布均匀,有序性好。微孔在膜的表... 在草酸体系中,采用二次阳极氧化法可制备大面积有序铝阳极氧化多孔膜(AAO),用X射线粉末衍射(XRD)仪进行物相分析,利用扫描电子显微镜(SEM)表征多孔膜的形貌。研究表明,低温条件下制备的多孔膜孔径大小分布均匀,有序性好。微孔在膜的表面沿二维空间规则排列,具有一定的六方对称准周期性,孔道相互平行且与铝基底垂直。低温条件下,草酸体系中电解获得的AAO膜以无定形结构存在,经过800℃高温退火后转化为γAl2O3。通过水热反应法,获得了Eu3+的铝阳极氧化多孔膜组装体(AAO∶Eu3+ ),研究了组装体系的光谱特性。结果表明,这种方法制备的发光材料具有非常高的组装浓度,其发光具有很高的色纯度。 展开更多
关键词 阳极氧化 多孔膜 退火 eu^3+ 水热反应法
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SiO_(2)包覆对SrAl_(2)O_(4):Eu^(2+),Dy^(3+)及其复合涂层发光性能影响
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作者 胡春霞 闫旺 +1 位作者 胡伟 李晶 《机械研究与应用》 2021年第4期28-31,共4页
以正硅酸乙酯(TEOS)为前驱体,采用溶胶-凝胶法制得SiO_(2)-SrAl_(2)O_(4)包覆粉体,利用超音速等离子喷涂技术在45#钢基体上制备了Cu-14Al-X/SrAl_(2)O_(4)(未包覆/包覆)复合涂层。采用扫描电子显微镜、X射线衍射仪和激光粒度分析仪对SrA... 以正硅酸乙酯(TEOS)为前驱体,采用溶胶-凝胶法制得SiO_(2)-SrAl_(2)O_(4)包覆粉体,利用超音速等离子喷涂技术在45#钢基体上制备了Cu-14Al-X/SrAl_(2)O_(4)(未包覆/包覆)复合涂层。采用扫描电子显微镜、X射线衍射仪和激光粒度分析仪对SrAl_(2)O_(4):Eu^(2+),Dy^(3+)磷光粉和SiO_(2)-SrAl_(2)O_(4)包覆粉体进行表征。利用荧光分光光度计对包覆前后磷光粉及Cu-14Al-X/SrAl_(2)O_(4)(未包覆/包覆)复合涂层的发光性能进行分析,探究超音速等离子喷涂过程中SiO_(2)表面包覆防猝灭工艺效果。结果表明:SiO_(2)包覆膜层未改变SrAl_(2)O_(4):Eu^(2+),Dy^(3+)磷光粉的晶体结构,对磷光粉的发光性能影响不大,可起到有效的隔离和保护作用,使磷光粉的发光性能得到改善,防猝灭效果较好。 展开更多
关键词 SiO_(2)包覆 SrAl_(2)O_(4):eu^(2+) Dy^(3+)磷光粉 发光性能
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Synthesis of Fe_3O_4 Magnetic Powder from Spent Pickling Liquors 被引量:1
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作者 Xingyao Wang Feifei Lv 《Transactions of Tianjin University》 EI CAS 2018年第1期45-50,共6页
Spent pickling liquors pose a serious environmental problem in most industrialized countries, mainly owing to their corrosive properties and their ferrous iron and hydrochloric acid content. In this paper, spent pickl... Spent pickling liquors pose a serious environmental problem in most industrialized countries, mainly owing to their corrosive properties and their ferrous iron and hydrochloric acid content. In this paper, spent pickling liquor was used as an inexpensive raw material to prepare Fe304 magnetic powder via an oxidation method. Being able to recover the dissolved iron from spent pickling liquors would not only salvage a valuable material but also render the effluent environmentally benign. The structure of the Fe_3O_4 magnetic powder was characterized by X-ray diffraction. The morphology and size were characterized by scanning electron microscopy and transmission electron microscopy. Their magnetic properties were tested at room temperature by a vibrating sample magnetometer. In addition, the saturation magnetization of Fe_3 O_4 products can be further enhanced to 96.1 emu/g after purification. 展开更多
关键词 SPENT PICKLING LIQUOR FE3O4 magnetic powder oxidATION
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片状YBO_3:Eu^(3+)荧光粉的水热合成及其光致发光性质
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作者 张利 许泳吉 《广州化工》 CAS 2012年第8期106-108,共3页
利用水热法在低温下制备了YBO3∶Eu3+发光材料,并利用X-射线衍射(XRD)、场发射扫描电子显微镜(SEM)、荧光光谱(PL)手段对样品进行表征。结果表明:180℃下水热法制备的YBO3∶Eu3+荧光粉为纳米片状结构;当Eu3+掺杂浓度为6%时,YBO3∶Eu3+... 利用水热法在低温下制备了YBO3∶Eu3+发光材料,并利用X-射线衍射(XRD)、场发射扫描电子显微镜(SEM)、荧光光谱(PL)手段对样品进行表征。结果表明:180℃下水热法制备的YBO3∶Eu3+荧光粉为纳米片状结构;当Eu3+掺杂浓度为6%时,YBO3∶Eu3+达到最大的发光强度。 展开更多
关键词 YBO3eu3+ 水热法 荧光粉 片状 光致发光
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Effects of Heat-treatment Temperature on Eu^(3+) and Li^+ Co-doped ZnO Photoluminescence by Sol-gel Process 被引量:1
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作者 卢忠远 HE +5 位作者 Fangfang 许丕池 TENG Yuancheng WANG Bing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第1期20-23,共4页
The photoluminescence (PL) characteristics of Eu^3+ and Li^+ co-doped ZnO PL materials against heat-treatment temperature were discussed. The PL xerogel and powder samples were prepared by solgel process. The emis... The photoluminescence (PL) characteristics of Eu^3+ and Li^+ co-doped ZnO PL materials against heat-treatment temperature were discussed. The PL xerogel and powder samples were prepared by solgel process. The emission spectra of all samples showed two broad bands peaking at 590 nm and 620 nm under UV-Vis excitation. But the relative intensity of red PL (620 nm) was much greater than that of green PL (590 nm) of the same sample, that s to say, the red color was the main luminescence. With heat-treatment temperature increase, the two kinds of colors PL intensity decreased, and both the red and green PL intensity of the xerogel samples was much greater than those of powder samples respectively. The XRD patterns revealed that Eu^3+ ions were successfully incorporated in ZnO crystals in xerogel samples. When heat-treatment temperature reached 350 ℃, the Eu^3+ began to separate out of the ZnO crystals and Eu2O3 crystals came into being. When the powder sample was subjected to UV-Vis excitation, the energy transfered from the host ZnO emission to Eu^3+ became weaker than the xerogel sample. 展开更多
关键词 PHOTOLUMINESCENCE eu^3+ and Li^+ co-doped ZnO UV-Vis excitation xerogel powder
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Effect of Al^3+ on Photoluminescence Properties of Eu^3+-Doped BaZr(BO3)2 Phosphors
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作者 李光昱 李岚 +2 位作者 王达健 张晓松 陶怡 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第8期2063-2065,共3页
We discuss the influence of Al^3+ on the charge transfer state (CTS) and the photoluminescence properties of BaZr(BO3)2:Eu. The results reveal that there is a red shift which is about 20nm for the charge transfe... We discuss the influence of Al^3+ on the charge transfer state (CTS) and the photoluminescence properties of BaZr(BO3)2:Eu. The results reveal that there is a red shift which is about 20nm for the charge transfer state when doping with Al^3+ and indicate the formation of ‘free' electrons due to the change of microstructures. In addition, the influence or Al^3+ doping on the PPR is analysed and a new explanation is raised based on the photo luminescent mechanism. It is the CTS intensity rather than the CTS energy that influences the peak-peak ratio. 展开更多
关键词 LUMINESCENT PROPERTIES oxideS eu3
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Comparative Assessment on Microstructure and Properties of in-situ TiC+Ti_(5)Si_(3)Reinforced TiAl-Sn-Zr Matrix Composites by Spark Plasma Sintering and Argon Protected Sintering 被引量:1
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作者 姚辉 许晓静 +4 位作者 CAI Chengbin LI Chen CHEN Fenghua LIU Yangguang XIAO Yishui 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第1期199-205,共7页
The effects of SiC particles(SiCp)on high temperature oxidation behavior of titanium matrix composites(TMCs)under different powder metallurgy processes were investigated.In situ Ti C+Ti_(5)Si_(3)reinforced titanium ma... The effects of SiC particles(SiCp)on high temperature oxidation behavior of titanium matrix composites(TMCs)under different powder metallurgy processes were investigated.In situ Ti C+Ti_(5)Si_(3)reinforced titanium matrix composites were prepared by discharge plasma sintering(SPS)and argon protective sintering(APS).The results show that the two processes have a negligible effect on the composition and hardness of the samples,but the hardness of the two samples is significantly improved by adding SiCp.The apparent porosity of SPS process is obviously smaller than that of APS process,whereas,the apparent porosity increases slightly with the addition of SiCp.The oxide layer thickness and mass gain of the samples obtained by SPS process are smaller than those obtained by APS process.The oxide thickness and mass gain of both processes are further reduced by adding SiCp.The SPS composites showed the best high temperature oxidation resistance.Therefore,TMCs with Si Cp by SPS can effectively improve the high-temperature oxidation behavior of the materials. 展开更多
关键词 powder metallurgy titanium matrix composites High-temperature oxidation TiC and Ti_(5)Si_(3) Ti-Al-Sn-Zr
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