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Effects of complexing agents on acidic electroless nickel deposition 被引量:6
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作者 JIN Ying YU Hongying +1 位作者 YANG Dejun SUN Dongbai 《Rare Metals》 SCIE EI CAS CSCD 2010年第4期401-406,共6页
Our previous study reported the influences of different complexing agents on electroless nickel (EN) by examining the properties of the deposits. In the present work, the effects of four common-used complexing agent... Our previous study reported the influences of different complexing agents on electroless nickel (EN) by examining the properties of the deposits. In the present work, the effects of four common-used complexing agents on EN deposition rate and the stability of solution pH values were examined, either with an acetic pH buffer agent or absent of them. It is indicated that the pH buffeting effect of them is dominative when the EN solution is lack of the pH buffer. Under this situation, the EN deposition rate increases with the concentration of complexing agents increasing. The EN deposition rate decreases with fin'ther adding the complexing agent when the solution already has enough pH buffer capability. Electrochemical impedance spectroscopy obtained during EN deposition illustrates that, in this case, the enhanced reaction resistance is the main reason for a lower deposition rate. However, the influence of polarization caused by mass transfer is not negligible at high complex ratio for sodium citrate and malic acid EN solutions. 展开更多
关键词 electroless nickel complexing agents electrochemical impedance spectrum reaction resistance pH value
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Facile synthesis of La_2Mo_2O_9 nanoparticles via an EDTA complexing approach 被引量:1
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作者 CHENG Hua WANG Hongen +2 位作者 LI Liang LU Zhouguang QIAN Dong 《Rare Metals》 SCIE EI CAS CSCD 2008年第4期340-344,共5页
A facile EDTA (ethylene diamine tetraacetic acid) complexing technique has been successfully employed to prepare La2Mo2O9 nanoparticles. The as-synthesized products are characterized by X-ray diffraction (XRD), sc... A facile EDTA (ethylene diamine tetraacetic acid) complexing technique has been successfully employed to prepare La2Mo2O9 nanoparticles. The as-synthesized products are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR). The results show that a homogeneous transparent gel can be obtained with EDTA as the organic complexing reagent under the pH value of 3.0. Further thermal decomposition of the as-synthesized transparent gel by increasing the temperature up to 600℃ for 3 h results in the formation of La2Mo2O9 nanoparticles with a crystal size of about 30 nm. Moreover, the nanoparticles tend to form micrometer-sized aggregates with a three-dimensional network structure, which shows promising applications in solid oxide fuel cells (SOFC), catalysts and so on. 展开更多
关键词 inorganic non-metal materials EDTA complexing SOL-GEL La2Mo2O9 NANOPARTICLES porous structure
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Structure and Shape Control of Hydrothermally Synthesized PbTiO_3 --Effects of pH and Complexing Agents 被引量:1
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作者 XIAO Li-hua +2 位作者 CHEN Dai-rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第1期1-5,共5页
Tabular PE PbTiO 3, spherical PY PbTiO 3, and acicular PX PbTiO 3 powders were hydrothermally synthesized from triethanolamine(TEA) complexed precursor; clubbed PE PbTiO 3 powders were obtained from diethanol... Tabular PE PbTiO 3, spherical PY PbTiO 3, and acicular PX PbTiO 3 powders were hydrothermally synthesized from triethanolamine(TEA) complexed precursor; clubbed PE PbTiO 3 powders were obtained from diethanolamine(DEA) complexed precursor. The effects of pH of the hydrolyzation as well as complexing agents including TEA, DEA, and MEA(monoethanolamine) on the structure and the morphology of PbTiO 3 powders are discussed. The optimal conditions for hydrothermal syntheses of acicular and clubbed PbTiO 3 powders have been established. The products were characterized by means of XRD, TEM and other techniques. 展开更多
关键词 Lead titanate Hydrothermal synthesis complexing agent
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Study on copper complexing ligand concentrations in several China's coastal waters
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作者 GONG Haidong ZHANG Zhengbin LIU Chunying LIU Liansheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第1期64-77,共14页
Copper complexing ligand concentrations in the Daya Bay, Qingdao coast, Jiaozhou Bay, South China Sea and Huanghe Estuary waters were determined by the anodic stripping voltammetry technique. The distribution regulari... Copper complexing ligand concentrations in the Daya Bay, Qingdao coast, Jiaozhou Bay, South China Sea and Huanghe Estuary waters were determined by the anodic stripping voltammetry technique. The distribution regularity and the relationship with other parameters were discussed. The results were as follows: Copper complexing ligand concentrations of the South China Sea were a little higher than those of other sea areas, and they were apparently higher than those of the ocean. Compared with the subsurface layer (SSL) in the sea surface microlayer copper complexing ligand concentrations showed an enrichment phenomenon, of which the mechanism is similar to dissolved organic matter. The metal complexing ligand concentration profiles of the South China Sea showed that the value in the sea surface was the highest, then it decreased with depth accruing, and a higher value appeared at the bottom. Copper complex- ing ligand concentrations were higher than those of cadmium and lead. Ligands in each sea area exhibited a complicated property. In short, the distribution regularity of copper complexing ligand concentrations in China's coastal waters was consistent with that of other regions in the world. Meanwhile, the positive relationship between the copper complexing ligand concentrations and biological oxygen demand, chemical oxygen demand, dissolved organic carbon, and viscosity were found clearly. 展开更多
关键词 copper complexing ligand concentrations China' s coastal waters distribution regularity RELATIONSHIP
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Synthesis and Complexing Properties of Three Aminopolyphosphonic Acids with Rare Earth Ions
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作者 高锦章 赵国虎 +2 位作者 韩小茜 康敬万 王荣 《Rare Metals》 SCIE EI CAS CSCD 1999年第4期254-263,共10页
Three white crystalline aminopolyphosphonic acids, DTHMP, TTHMP and TPHMP were synthesized by a modified Mannich reaction under gentle conditions. The products were isolated and purified with a SP-Sephadex C-25 column... Three white crystalline aminopolyphosphonic acids, DTHMP, TTHMP and TPHMP were synthesized by a modified Mannich reaction under gentle conditions. The products were isolated and purified with a SP-Sephadex C-25 column. The acid-base and complexing properties of three aminopolyphosphonic acids with rare earth ions were investigated by means of potentiometric titration in aqueous medium at (25 +/- 0.1) degrees C and ionic strength I = 0.1 mol/L KNO3. The successive protonation constants of ligands and the formation constants of complexes with rare earth elements were obtained. The results show a double-double effect for lgK(MHiL) against atomic number of lanthanide. The properties are advantageous for the separation of the rare earth elements. 展开更多
关键词 rare earth elements aminopolyphosphonic acid complexing properties
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Agglomerate control in the complexing sol-gel process
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作者 尹邦跃 王零森 +1 位作者 樊毅 张金生 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第4期712-716,共5页
Nanometer ZrO2 - 8% Y2O3 (mole fraction, % ) powders were prepared by the EDTA (ethylenediaminetetraacetic acid) sol-gel process. Effects of the addition of ethylene glycol on agglomerate control was investigated. The... Nanometer ZrO2 - 8% Y2O3 (mole fraction, % ) powders were prepared by the EDTA (ethylenediaminetetraacetic acid) sol-gel process. Effects of the addition of ethylene glycol on agglomerate control was investigated. The results showed that because of the replacement of hydrogen bonds with ethylene glycol in the polymerized gel, gel stabilization and homogeneity were improved and close approach of gel particles was prevented, which led to reduction of hard agglomerates to some extent. Calcined at 4OO t for 2 h and 700 C for 2 h, the powders had a specific surface area of 35 m2/g, average particle size of 28 nm, and median particle size (d50) of 0. 44um with very sharp distribution, mostly being soft agglomerates. 展开更多
关键词 complexing EDTA SOL-GEL process ZrO2 (Y2O3) AGGLOMERATION
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The Effect of Improving soil Fertility on Status of Organo-mineral Complexing in Chestnut soils
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作者 Liu Shuqing Huo Xiliang(Agricultural University of Hebei,Baoding 071001) 《河北农业大学学报》 CAS CSCD 北大核心 1995年第S1期41-46,共6页
TheEffectofImprovingsoilFertilityonStatusofOrgano-mineralComplexinginChestnutsoils¥LiuShuqing;HuoXiliang(Agr... TheEffectofImprovingsoilFertilityonStatusofOrgano-mineralComplexinginChestnutsoils¥LiuShuqing;HuoXiliang(AgriculturalUniversi... 展开更多
关键词 CHESTNUT complexing
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Positively charged nanofiltration membrane fabricated by poly(acid–base) complexing effect induced phase inversion method for heavy metal removal 被引量:1
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作者 Chunli Liu Weihui Bi +2 位作者 Dongliang Chen Suobo Zhang Hongchao Mao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第11期1685-1694,共10页
Poly(arylene ether ketone)s with carboxylic groups(PAEK-COOH)is a good membrane fabrication material,a kind of polyacids,while polyethylenimine(PEI)is a weak organic base,a kind of polybases.Those polyacids and polyba... Poly(arylene ether ketone)s with carboxylic groups(PAEK-COOH)is a good membrane fabrication material,a kind of polyacids,while polyethylenimine(PEI)is a weak organic base,a kind of polybases.Those polyacids and polybases would form ionic complexation at the interface of two liquid phases.In this paper,PAEK-COOH/N-methyl pyrrolidone(NMP)/1,4-dioxane(DO)mixture,employed as polymer casting solution and aqueous solution of PEI,used as coagulation bath,respectively.Then ion complexation induced phase inversion process is applied to prepare positively charged nanofiltration membrane with thinner but denser separation skin layer.The complexing reaction at the interface of two liquid phases has great influence on the kinetic aspects of phase inversion process,which in accordance would affect the morphology and performance of the membrane.The obtained membrane,fabricated via the ion complexation induced phase inversion method,is positively charged,has high water permeability,and possesses high rejection towards divalent cations,such as Mg^(2+),Ca^(2+),Pb^(2+)etc.,which could be used for removal of heavy metals from polluted water.At the optimal condition,the pure water flux of the PAEK-COOH-PEI nanofiltration membrane is 24.3 L·m^(-2)·h^(-1),with MgCl_2rejection of 92.2%. 展开更多
关键词 POLYELECTROLYTE complex Carboxylated polymer POLYETHYLENIMINE NANOFILTRATION Water PURIFICATION
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Syntheses,Crystal Structures and Complexing Properties of 1,3-Distal Calix[4]arene Schiff Bases 被引量:1
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作者 LI Liang GU Wei-wei YAN Chao-guo 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第1期38-45,共8页
Novel 1,3-distal p-tert-butylcalix[4]arene Schiff bases were efficiently synthesized in three steps. At first p-tert-hutylcalix[4]arene was reacted with N-2-hydroxyethylphthalimide catalyzed by TPP/DEAD or alkylated w... Novel 1,3-distal p-tert-butylcalix[4]arene Schiff bases were efficiently synthesized in three steps. At first p-tert-hutylcalix[4]arene was reacted with N-2-hydroxyethylphthalimide catalyzed by TPP/DEAD or alkylated with ω-hatoalkylphthalimide in the system of K2CO3/KI/CH3COCH3 to give 1,3-distal diphthalimidoalkyl calixarenes, which were in turn hydrazinolyzed to give diaminoalkyl calixarenes. Then with the aid of the condensation of active calixarene amines with salicylaldehyde, 2-hydroxy-l-naphthaldehyde or pyridine-2-carboxaldehyde, a series of 1,3-distal calixarene Schiff bases was prepared in satisfied yields. The single crystal structures and complexing properties of these Schiff bases for transition metal ions were studied. 展开更多
关键词 CALIXARENE Schiffbase Crystal structure Metal complex UV spectroscopy
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Studies on the Synthesis and Complexing Behavior of Crown Ethers with External Coordination Center 被引量:1
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作者 Jing Chao TAO Yang Jie WU* +1 位作者 Shang Jie XU Da Peng ZOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第6期479-482,共4页
The synthesis, characterization of five ditopic or tritopic crown compounds were reported in this paper together with the preparation of the corresponding hetero-dinuclear and hetero-trinuclear complexes with differen... The synthesis, characterization of five ditopic or tritopic crown compounds were reported in this paper together with the preparation of the corresponding hetero-dinuclear and hetero-trinuclear complexes with different metal cations. 展开更多
关键词 Polytopic crown ether hetero-polynuclear complex CO-ORDINATION
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Complexing Properties of Acid Alizarin Violet with Copper, Cobalt and Nickel in Micellar Media Containing SDS, CTAB and TX-100
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作者 Fawwaz Jumean Magdy El-Dakiky +3 位作者 Adnan Manassra Manal Abdul Kareem Mohammad Abu Alhaj Mustafa Khamis 《American Journal of Analytical Chemistry》 2014年第1期1-7,共7页
The interaction of the dye acid alizarin violet (AVN) with three transition metals was followed spectrophotometrically in water and in micellar solutions of the cationic cetyltrimethylammonium bromide (CTAB), the anio... The interaction of the dye acid alizarin violet (AVN) with three transition metals was followed spectrophotometrically in water and in micellar solutions of the cationic cetyltrimethylammonium bromide (CTAB), the anionic sodium dode- cyl sulfate (SDS) and the nonionic triton X-100 (TX-100). The stoichiometric ratios for the complexes of AVN with each metal ion were determined by the mole ratio and the continuous variation methods. In water, the metal to dye ratios in the complexes were 1:2, 1:3 and 1:1 for Cu2+, Co2+ and Ni2+, respectively. For Ni2+ the ratio changed to 1:3 in micellar CTAB. All other ratios were unchanged in the three micellar solutions. The formation constant (βn) of the complex in water was 1.00 × 1010 for Cu2+, 4.66 × 1014 for Co2+ and 9.03 × 104 for Ni2+. βn decreased in micellar TX-100: for Cu2+ to 6.88 × 108, for Co2+ to 1.56 × 1014 and for Ni2+ to 8.65 × 104. By contrast, micellar CTAB increased βn for Cu2+ and Ni2+. For Cu2+, the increase was to 5.19 × 1010, but for Ni2+ a large jump was observed, to 1.16 × 1015. For Co2+, βn dropped to 2.16 × 1014 in CTAB. Micellar SDS decreased βn for Cu2+ and Co2+ complexes to 5.38 × 109 and 1.76 × 1014, respectively, but increased that of the Ni2+ complex to 4.40 × 105. These observations were explained in terms of structural properties. 展开更多
关键词 COMPLEXATION AVN MICELLIZATION
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全耳内镜下耳屏软骨-软骨膜复合体在上鼓室外侧壁重建中的临床应用
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作者 田爱民 邹明臻 孔磊 《中国耳鼻咽喉头颈外科》 CSCD 2024年第6期395-398,共4页
目的探究全耳内镜下耳屏软骨-软骨膜复合体在上鼓室外侧壁重建中的临床应用。方法选取2020年6月~2023年6月间徐州市中心医院收治的58例进行上鼓室外侧壁重建的胆脂瘤患者,根据采用修复材料的不同分为对照组及观察组各29例。对照组采用... 目的探究全耳内镜下耳屏软骨-软骨膜复合体在上鼓室外侧壁重建中的临床应用。方法选取2020年6月~2023年6月间徐州市中心医院收治的58例进行上鼓室外侧壁重建的胆脂瘤患者,根据采用修复材料的不同分为对照组及观察组各29例。对照组采用耳屏软骨膜进行上鼓室外侧壁重建,观察组采用耳屏软骨-软骨膜复合体进行上鼓室外侧壁重建,两组患者均于全耳内镜下进行手术。统计患者术中出血量、手术时间,术后3个月复查听力情况、干耳情况及耳道功能改善情况,术后随访6个月鼓膜愈合情况。结果与术前比较,术后3个月气导听阈、气骨导差降低(P<0.05),与对照组比较,观察组气导听阈、气骨导差降低(P<0.05);与对照组比较,观察组干耳率、耳道功能良好率、听力提高成功率均升高,干耳时间缩短,但耳屏愈合时间增加(P<0.05);与对照组比较,观察组手术时间缩短,术中出血量减少(P<0.05);观察组、对照组术后并发症总发生率分别为13.79%、24.14%,二者比较差异无统计学意义(P>0.05);观察组愈合良好率高于对照组(86.21%vs.62.07%)(P<0.05),两组患者耳膜穿孔(10.34%vs.24.14%)、鼓膜移位(3.45%vs.6.90%)及鼓膜回缩(0.00%vs.6.90%)发生情况比较,差异无统计学意义(P>0.05)。结论全耳内镜下耳屏软骨-软骨膜复合体在上鼓室外侧壁重建中有利于改善患者听力,有利于术后恢复。 展开更多
关键词 胆脂瘤(Cholesteatoma) 鼓室成形术(Tympanoplasty) 耳软骨(Ear Cartilage) 复合体(Compomers) 上鼓室外侧壁重建(reconstruction of lateral attic wall) 耳屏软骨-软骨膜复合体(tragus cartilage-perichondrium complex) 耳内镜(otoendoscopy)
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Recent Progress in Reinforcement Learning and Adaptive Dynamic Programming for Advanced Control Applications 被引量:2
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作者 Ding Wang Ning Gao +2 位作者 Derong Liu Jinna Li Frank L.Lewis 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期18-36,共19页
Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and ... Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and its applications to various advanced control fields. First, the background of the development of ADP is described, emphasizing the significance of regulation and tracking control problems. Some effective offline and online algorithms for ADP/adaptive critic control are displayed, where the main results towards discrete-time systems and continuous-time systems are surveyed, respectively.Then, the research progress on adaptive critic control based on the event-triggered framework and under uncertain environment is discussed, respectively, where event-based design, robust stabilization, and game design are reviewed. Moreover, the extensions of ADP for addressing control problems under complex environment attract enormous attention. The ADP architecture is revisited under the perspective of data-driven and RL frameworks,showing how they promote ADP formulation significantly.Finally, several typical control applications with respect to RL and ADP are summarized, particularly in the fields of wastewater treatment processes and power systems, followed by some general prospects for future research. Overall, the comprehensive survey on ADP and RL for advanced control applications has d emonstrated its remarkable potential within the artificial intelligence era. In addition, it also plays a vital role in promoting environmental protection and industrial intelligence. 展开更多
关键词 Adaptive dynamic programming(ADP) advanced control complex environment data-driven control event-triggered design intelligent control neural networks nonlinear systems optimal control reinforcement learning(RL)
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Historical biogeography and evolutionary diversification of Lilium(Liliaceae): New insights from plastome phylogenomics 被引量:1
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作者 Nian Zhou Ke Miao +4 位作者 Changkun Liu Linbo Jia Jinjin Hu Yongjiang Huang Yunheng Ji 《Plant Diversity》 SCIE CAS CSCD 2024年第2期219-228,共10页
Here, we infer the historical biogeography and evolutionary diversification of the genus Lilium. For this purpose, we used the complete plastomes of 64 currently accepted species in the genus Lilium(14plastomes were n... Here, we infer the historical biogeography and evolutionary diversification of the genus Lilium. For this purpose, we used the complete plastomes of 64 currently accepted species in the genus Lilium(14plastomes were newly sequenced) to recover the phylogenetic backbone of the genus and a timecalibrated phylogenetic framework to estimate biogeographical history scenarios and evolutionary diversification rates of Lilium. Our results suggest that ancient climatic changes and geological tectonic activities jointly shaped the distribution range and drove evolutionary radiation of Lilium, including the Middle Miocene Climate Optimum(MMCO), the late Miocene global cooling, as well as the successive uplift of the Qinghai-Tibet Plateau(QTP) and the strengthening of the monsoon climate in East Asia during the late Miocene and the Pliocene. This case study suggests that the unique geological and climatic events in the Neogene of East Asia, in particular the uplift of QTP and the enhancement of monsoonal climate, may have played an essential role in formation of uneven distribution of plant diversity in the Northern Hemisphere. 展开更多
关键词 Asian monsoon Climatic changes Distribution range Evolutionary complexity Radiative diversification Species diversity Qinghai-Tibet Plateau(QTP)
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COMPLETE KAHLER METRICS WITH POSITIVE HOLOMORPHIC SECTIONAL CURVATURES ON CERTAIN LINE BUNDLES(RELATED TO A COHOMOGENEITY ONE POINT OF VIEW ON A YAU CONJECTURE) 被引量:1
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作者 段晓曼 关庄丹 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期78-102,共25页
In this article,we study Kahler metrics on a certain line bundle over some compact Kahler manifolds to find complete Kahler metrics with positive holomorphic sectional(or bisectional)curvatures.Thus,we apply a strateg... In this article,we study Kahler metrics on a certain line bundle over some compact Kahler manifolds to find complete Kahler metrics with positive holomorphic sectional(or bisectional)curvatures.Thus,we apply a strategy to a famous Yau conjecture with a co-homogeneity one geometry. 展开更多
关键词 Kahler Metrics complete Riemannian metrics open complex manifolds holomorphic bisectional curvature C*bundle almost homogeneous manifolds
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Effect of FA/O complexing agents and H_2O_2 on chemical mechanical polishing of ruthenium in weakly alkaline slurry 被引量:2
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作者 段波 安卫静 +1 位作者 周建伟 王帅 《Journal of Semiconductors》 EI CAS CSCD 2015年第7期154-158,共5页
This paper investigated the effect of FA/O and hydrogen peroxide (H2O2) on ruthenium (Ru) removal rate (RR) and static etching rate (SER). It was revealed that Ru RR and SER first linearly increased then slowl... This paper investigated the effect of FA/O and hydrogen peroxide (H2O2) on ruthenium (Ru) removal rate (RR) and static etching rate (SER). It was revealed that Ru RR and SER first linearly increased then slowly decreaseed with the increasing H2O2 probably due to the formation of uniform Ru oxides on the surface during polishing. Their corrosion behaviors and states of surface oxidation were analyzed. In addition, FA/O could chelate Ru oxides (such as (RuO4)2- and RUO4- changed into soluble amine salts [R(NH3)4] (RuO4)2) and enhance Ru RR. The non-ionic surfactant AD was used to improve the Ru CMP performance. In particular, the addition of AD can lead to significant improvement of the surface roughness. 展开更多
关键词 Ru chemical mechanical polishing FA/O complexing agents hydrogen peroxide non-ionic surfactant AD
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Solvent extraction and separation of light rare earth elements (La, Pr and Nd) in the presence of lactic acid as a complexing agent by Cyanex 272 in kerosene and the effect of citric acid,acetic acid and Titriplex Ⅲ as auxiliary agents 被引量:14
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作者 Eslam Kashi Razieh Habibpour +1 位作者 Hesamoddin Gorzin Armin Maleki 《Journal of Rare Earths》 SCIE EI CAS CSCD 2018年第3期317-323,共7页
At present, the use of rare earth elements(REEs) has become an inevitable necessity in many modern industries. In general, liquid extraction is the best commercial method for extracting REEs due to its ability to co... At present, the use of rare earth elements(REEs) has become an inevitable necessity in many modern industries. In general, liquid extraction is the best commercial method for extracting REEs due to its ability to control high volumes of liquids with electrical load. With the aim of improving a separation technology that would be superior to the existing extraction systems, the extraction behaviors of La(Ⅲ),Pr(Ⅲ), and Nd(Ⅲ) from an HCI medium with Cyanex 272 in the presence of the complexing agent lactic acid(HLac) and auxiliary agents citric acid(H3 Cit), acetic acid(HAc), and Titriplex Ⅲ have been reported.The effect of pH and lactic acid concentration has been examined. The use of lactic acid as a complexing agent leading to a high extraction of REEs with Cyanex 272 at pH = 5 was compared with systems without lactic acid. The results show that the use of acetic acid along with lactic acid leads to an increase in the extraction percentage of LREEs. While use of citric acid and Titriplex Ⅲ reduces the extraction percentage of LREEs. Finally, the presence of Titriplex Ⅲ together with lactic acid could lead to an increase in the separation factor of Pr and Nd. 展开更多
关键词 Light rare earth elements(LREEs) Solvent extraction Cyanex 272 Lactic acid complexing agent Auxiliary agents Rare earths
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A novel complex-high-order graph convolutional network paradigm:ChyGCN
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作者 郑和翔 苗书宇 顾长贵 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期665-672,共8页
In recent years,there has been a growing interest in graph convolutional networks(GCN).However,existing GCN and variants are predominantly based on simple graph or hypergraph structures,which restricts their ability t... In recent years,there has been a growing interest in graph convolutional networks(GCN).However,existing GCN and variants are predominantly based on simple graph or hypergraph structures,which restricts their ability to handle complex data correlations in practical applications.These limitations stem from the difficulty in establishing multiple hierarchies and acquiring adaptive weights for each of them.To address this issue,this paper introduces the latest concept of complex hypergraphs and constructs a versatile high-order multi-level data correlation model.This model is realized by establishing a three-tier structure of complexes-hypergraphs-vertices.Specifically,we start by establishing hyperedge clusters on a foundational network,utilizing a second-order hypergraph structure to depict potential correlations.For this second-order structure,truncation methods are used to assess and generate a three-layer composite structure.During the construction of the composite structure,an adaptive learning strategy is implemented to merge correlations across different levels.We evaluate this model on several popular datasets and compare it with recent state-of-the-art methods.The comprehensive assessment results demonstrate that the proposed model surpasses the existing methods,particularly in modeling implicit data correlations(the classification accuracy of nodes on five public datasets Cora,Citeseer,Pubmed,Github Web ML,and Facebook are 86.1±0.33,79.2±0.35,83.1±0.46,83.8±0.23,and 80.1±0.37,respectively).This indicates that our approach possesses advantages in handling datasets with implicit multi-level structures. 展开更多
关键词 raph convolutional network complex modeling complex hypergraph
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A novel variable-order fractional chaotic map and its dynamics
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作者 唐周青 贺少波 +3 位作者 王会海 孙克辉 姚昭 吴先明 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期281-290,共10页
In recent years,fractional-order chaotic maps have been paid more attention in publications because of the memory effect.This paper presents a novel variable-order fractional sine map(VFSM)based on the discrete fracti... In recent years,fractional-order chaotic maps have been paid more attention in publications because of the memory effect.This paper presents a novel variable-order fractional sine map(VFSM)based on the discrete fractional calculus.Specially,the order is defined as an iterative function that incorporates the current state of the system.By analyzing phase diagrams,time sequences,bifurcations,Lyapunov exponents and fuzzy entropy complexity,the dynamics of the proposed map are investigated comparing with the constant-order fractional sine map.The results reveal that the variable order has a good effect on improving the chaotic performance,and it enlarges the range of available parameter values as well as reduces non-chaotic windows.Multiple coexisting attractors also enrich the dynamics of VFSM and prove its sensitivity to initial values.Moreover,the sequence generated by the proposed map passes the statistical test for pseudorandom number and shows strong robustness to parameter estimation,which proves the potential applications in the field of information security. 展开更多
关键词 CHAOS fractional difference variable order MULTISTABILITY COMPLEXITY
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Solar hydrogen production from electrochemical ammonia splitting powered by a single perovskite solar cell
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作者 Anna MBeiler Wenhui Li +2 位作者 Alisa Denisiuk Emilio Palomares Antoni Llobet 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期292-295,共4页
For carbon-free electrochemical fuel formation,the electrochemical cell must be powered by renewable energy.Obtaining solar-powered H_(2) fuel from water typically requires multiple photovoltaic cells and/or junctions... For carbon-free electrochemical fuel formation,the electrochemical cell must be powered by renewable energy.Obtaining solar-powered H_(2) fuel from water typically requires multiple photovoltaic cells and/or junctions to drive the water splitting reaction.Because of the lower thermodynamic requirements to oxidize ammonia compared to water,solar cells with smaller open circuit voltages can provide the required potential for ammonia splitting.In this work,a single perovskite solar cell with an open-circuit potential of 1.08 V is coupled to a 2-electrode electrochemical cell employing hybrid electroanodes functionalized with Ru-based molecular catalysts.The device is active for more than 30 min,producing N_(2) and H_(2) in a 1:2.9 ratio with 89%faradaic efficiency with no external applied bias.This work illustrates that hydrogen production from ammonia can be driven by conventional semiconductors. 展开更多
关键词 Ammonia oxidation Redox catalysis Perovskites Solarfuels Transitionmetal complexes
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