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Tailoring oxygen vacancies in Ni-doped In_(2)O_(3) for improved thin-film transistor stability and performance via solution processing
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作者 Fakhari Alam Sara Ajmal +3 位作者 Muhammad Asim Shahzad Ghulam Dastgeer Aamir Rasheed Gang He 《Journal of Semiconductors》 2026年第2期61-71,共11页
Doping in thin-film transistors(TFTs) plays a crucial role in tailoring material properties to enhance device performance, making them essential for advanced electronic applications. This study explores the synthesis ... Doping in thin-film transistors(TFTs) plays a crucial role in tailoring material properties to enhance device performance, making them essential for advanced electronic applications. This study explores the synthesis and characterization of TFTs fabricated using nickel(Ni)-doped indium oxide(In_(2)O_(3)) via a wet-chemical approach. The presented work investigates the effect of "Ni" incorporation in In_(2)O_(3) on the structural and electrical transport properties of In_(2)O_(3), revealing that higher "Ni" content decreases the oxygen vacancies, leading to a reduction in leakage current and a forward shift in threshold potential(V_(th)).Experimental findings reveal that Ni In O-based TFTs(with Ni = 0.5%) showcase enhanced electrical performance, achieving mobility of 7.54 cm^(2)/(V·s), an impressive ON/OFF current ratio of ~10^(7), a V_(th) of 6.26 V, reduced interfacial trap states(D_(it)) of 8.23 ×10^(12) cm^(-2) and enhanced biased stress stability. The efficacy of "Ni" incorporation is attributed to the upgraded Lewis acidity, stable Ni-O bond strength, and small ionic radius of Ni. Negative bias illumination stability(NBIS) measurements further indicate that device stability diminishes with shorter light wavelengths, likely due to the activation of oxygen vacancies. These findings validate the solution-processed techniques' potential for future large-scale, low-cost, energy-efficient, and high-performance electronics. 展开更多
关键词 thin-film transistors Ni-doped In_(2)O_(3) solution processing bias illumination stability
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The Construction of Exact Solutions of the Two-Dimensional Gardner Equation via the∂¯-Dressing Method
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作者 Binlu FENG Linlin GUI Yufeng ZHANG 《Journal of Mathematical Research with Applications》 2025年第6期758-772,共15页
The(2+1)-dimensional integrable generalization of the Gardner(2DG)equation is solved via the inverse scattering transform method in this paper.A kind of general solution of the equation is obtained by introducing long... The(2+1)-dimensional integrable generalization of the Gardner(2DG)equation is solved via the inverse scattering transform method in this paper.A kind of general solution of the equation is obtained by introducing long derivatives V_(x),V_(y),V_(t).Two different constraints on the kernel function K are introduced under the reality of the solution u of the 2DG equation.Then,two classes of exact solutions with constant asymptotic values at infinity u|x^(2)+y^(2)→∞→0 are constructed by means of the∂¯-dressing method for the casesσ=1 andσ=i.The rational and multiple pole solutions of the 2DG equation are obtained with the kernel functions of zero-order and higher-order Dirac delta functions,respectively. 展开更多
关键词 2DG equation kernel function ∂¯-dressing method rational solution multiple pole solution
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Thermoelectric Performance of CuInSe_(2)‑ZnSe Solid Solution
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作者 Chengwei Sun Wang Li +6 位作者 Chengjun Li Yingchao Wei Wenyuan Ma Xin Li Qinghui Jiang Yubo Luo Junyou Yang 《Acta Metallurgica Sinica(English Letters)》 2025年第5期823-830,共8页
CuInSe_(2) is an N-type diamond-like semiconductors thermoelectric candidate for power generation at medium temperature with its environmentally friendly and cost-effective properties.However,the intrinsic high therma... CuInSe_(2) is an N-type diamond-like semiconductors thermoelectric candidate for power generation at medium temperature with its environmentally friendly and cost-effective properties.However,the intrinsic high thermal conductivity of CuInSe_(2) limits the enhancement of its thermoelectric performance.Herein,we investigate the thermoelectric performance of N-type CuInSe_(2) materials by incorporating ZnSe through a solid solution strategy.A series of(CuInSe_(2))_(1-x)(ZnSe)_(x)(x=0.0,0.2,0.4,0.6,0.8,1.0)samples were synthesized,forming continuous solid solutions,while introducing minor porosity.ZnSe solid solution effectively reduces the lattice thermal conductivity of the CuInSe_(2) matrix at near-room temperatures,but has a weaker effect at higher temperatures.Due to the intrinsic low carrier concentration of the system,resulting in high resistivity,the maximum figure of merit(ZT)of(CuInSe_(2))0.8(ZnSe)0.2 reaches 0.08 at 773 K.Despite the relatively low ZT,the solid solution strategy proves effective in reducing the lattice thermal conductivity near-room temperature and offers potential for cost-effective thermoelectric materials. 展开更多
关键词 THERMOELECTRIC CuInSe_(2) ZNSE Solid solution
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Adsorption process for purifying vanadium from chromium-contaminated leaching solutions using zirconium-based adsorbents
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作者 Biao Yuan Fujin Sun +5 位作者 Pingting Chen Kunpeng He Pan Wu Changjun Liu Jian He Wei Jiang 《Chinese Journal of Chemical Engineering》 2025年第6期125-137,共13页
With the development of vanadium redox flow battery technology,the demand for pure vanadium is rapidly increasing.The separation of vanadium from vanadium-chromium leaching solutions are critical step in the productio... With the development of vanadium redox flow battery technology,the demand for pure vanadium is rapidly increasing.The separation of vanadium from vanadium-chromium leaching solutions are critical step in the production of purity-vanadium.This study presents an innovative adsorption process that utilizes amorphous ZrO_(2)(AZrO) for the selective separation of V(Ⅴ) and Cr(Ⅵ).In this process,a high adsorption capacity for V(V) at 64.5 mg·g^(-1) was achieved,while the capacity for Cr(Ⅵ) is relatively low at 24.1 mg·g^(-1),demonstrating good separation performance.This is mainly caused by the large specific surface area and mesoporous structure,which are favorable for molecular diffusion and mass transfer.The kinetic analysis shows that the adsorption process follows pseudo-second-order kinetic process with chemisorption being the rate-controlling process.AZrO showed excellent separation performance in mixed solutions over a wide range of concentrations.After five cycles,AZrO retained over 73% of its capacity,indicating good stability.In mixed solutions containing up to 40 g·L^(-1) of V(Ⅴ) and 3 g·L^(-1) of Cr(Ⅵ),the innovative adsorption process successfully achieved effective separation and purification.By an adsorption-desorption process using 0.1 mol·L^(-1) NaOH,a 99.02% V(Ⅴ)-rich solution was obtained from a high concentration sodium vanadium slag leaching solution,demonstrating its effectiveness for practical industrial applications. 展开更多
关键词 Adsorption Amorphous ZrO2 Leaching solution Separation PURIFICATION
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Technical methods of carbon capture by seawater-based solution mineral carbonation
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作者 Shanshan Liu Jinming Song +4 位作者 Xuegang Li Huamao Yuan Liqin Duan Guorong Zhong Zhibo Wang 《Acta Oceanologica Sinica》 2025年第11期1-15,共15页
With global industrialization and the excessive use of fossil fuels,greenhouse gas emissions have substantially increased,particularly the concentrations of carbon dioxide(CO_(2)),which have had profound impacts on gl... With global industrialization and the excessive use of fossil fuels,greenhouse gas emissions have substantially increased,particularly the concentrations of carbon dioxide(CO_(2)),which have had profound impacts on global warming and extreme climate events.As a key technology to combat climate change,mineral carbonation has been widely recognized as an effective technique for CO_(2)sequestration and utilization.In recent years,seawater-based solutions(including desalination brine and seawater-based wastewater)have become a research hotspot in mineral carbonation due to their strong alkalinity,high content of Ca^(2+)and Mg^(2+),and lower costs compared to chemical solvents.This article comprehensively reviews the CO_(2)mineral carbonation mechanisms based on seawater-based solutions,highlighting recent research achievements and potential development trends in capturing CO_(2)through the pH swing method,modified Solvay process,chemical precipitation method,and chemical absorption method.By comparing the use of seawater-based solutions for mineral carbonation with traditional techniques,this study evaluates its advantages and the challenges it may face in practical applications,aiming to provide a more accurate assessment of the impact and future development of this technology. 展开更多
关键词 CO_(2)sequestration and utilization seawater-based solution mineral carbonation
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Navigating the Blockchain Trilemma:A Review of Recent Advances and Emerging Solutions in Decentralization,Security,and Scalability Optimization
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作者 Saha Reno Koushik Roy 《Computers, Materials & Continua》 2025年第8期2061-2119,共59页
The blockchain trilemma—balancing decentralization,security,and scalability—remains a critical challenge in distributed ledger technology.Despite significant advancements,achieving all three attributes simultaneousl... The blockchain trilemma—balancing decentralization,security,and scalability—remains a critical challenge in distributed ledger technology.Despite significant advancements,achieving all three attributes simultaneously continues to elude most blockchain systems,often forcing trade-offs that limit their real-world applicability.This review paper synthesizes current research efforts aimed at resolving the trilemma,focusing on innovative consensus mechanisms,sharding techniques,layer-2 protocols,and hybrid architectural models.We critically analyze recent breakthroughs,including Directed Acyclic Graph(DAG)-based structures,cross-chain interoperability frameworks,and zero-knowledge proof(ZKP)enhancements,which aimto reconcile scalability with robust security and decentralization.Furthermore,we evaluate the trade-offs inherent in these approaches,highlighting their practical implications for enterprise adoption,decentralized finance(DeFi),and Web3 ecosystems.By mapping the evolving landscape of solutions,this review identifies gaps in currentmethodologies and proposes future research directions,such as adaptive consensus algorithms and artificial intelligence-driven(AI-driven)governance models.Our analysis underscores that while no universal solution exists,interdisciplinary innovations are progressively narrowing the trilemma’s constraints,paving the way for next-generation blockchain infrastructures. 展开更多
关键词 Blockchain trilemma SCALABILITY DECENTRALIZATION SECURITY consensus algorithms sharding layer-2 solutions DAG-based architectures cross-chain interoperability blockchain optimization
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Hydrogen production from dry reforming of methane,using CO_(2)previously chemisorbed in the Li_(6)Zn_(1-x)Ni_(x)O_(4)solid solution
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作者 Yocelin B.González-González Fernando Plascencia-Hernández +1 位作者 Rubén Mendoza-Cruz Heriberto Pfeiffer 《Journal of Environmental Sciences》 2025年第3期535-550,共16页
Li_(6)ZnO_(4)was chemically modified by nickel addition,in order to develop different compositions of the solid solution Li_(6)Zn_(1-x)Ni_(x)O_(4).These materials were evaluated bifunctionally;analyzing their CO_(2)ca... Li_(6)ZnO_(4)was chemically modified by nickel addition,in order to develop different compositions of the solid solution Li_(6)Zn_(1-x)Ni_(x)O_(4).These materials were evaluated bifunctionally;analyzing their CO_(2)capture performances,aswell as on their catalytic properties for H_(2)production via dry reforming of methane(DRM).The crystal structures of Li_(6)Zn_(1-x)Ni_(x)O_(4)solid solution samples were determined through X-ray diffraction,which confirmed the integration of nickel ions up to a concentration around 20 mol%,meanwhile beyond this value,a secondary phase was detected.These results were supported by XPS and TEM analyses.Then,dynamic and isothermal thermogravimetric analyses of CO_(2)capture revealed that Li_(6)Zn_(1-x)Ni_(x)O_(4)solid solution samples exhibited good CO_(2)chemisorption efficiencies,similarly to the pristine Li_(6)ZnO_(4)chemisorption trends observed.Moreover,a kinetic analysis of CO_(2)isothermal chemisorptions,using the Avrami-Erofeev model,evidenced an increment of the constant rates as a function of the Ni content.Since Ni^(2+)ions incorporation did not reduce the CO_(2)capture efficiency and kinetics,the catalytic properties of thesematerialswere evaluated in the DRM process.Results demonstrated that nickel ions favored hydrogen(H_(2))production over the pristine Li_(6)ZnO_(4)phase,despite a second H2 production reaction was determined,methane decomposition.Thereby,Li_(6)Zn_(1-x)Ni_(x)O_(4)ceramics can be employed as bifunctional materials. 展开更多
关键词 Dry reforming of methane(DRM) CO_(2)chemisorption H_(2)production Solid solution Li_(6)ZnO_(4)
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Effect of ammonia solution on the electrochemical properties of magnesium manganese oxide material for aqueous zinc-ion batteries
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作者 Wasim Akram Syed Ashok Kumar Kakarla +2 位作者 Hari Bandi R.Shanthappa Jae Su Yu 《Journal of Magnesium and Alloys》 2025年第7期3271-3286,共16页
Aqueous zinc(Zn)-ion batteries(AZIBs)have gained significant interest in energy storage due to several unique advantages.Utilizing waterbased electrolytes enhances environmental sustainability,while the abundance and ... Aqueous zinc(Zn)-ion batteries(AZIBs)have gained significant interest in energy storage due to several unique advantages.Utilizing waterbased electrolytes enhances environmental sustainability,while the abundance and affordability of Zn offer economic benefits.Manganese(Mn)-based materials,commonly used as cathodes in these batteries,provide high theoretical capacity,high electrical conductivity,and good structural stability.However,these materials suffer from capacity degradation over repeated cycles due to structural collapse and limited conductivity.To address this problem,we synthesized a magnesium(Mg)-and Mn-based composite,Mg^(2+)-Mn_(3)O_(4),using the hydrothermal method with an optimized amount of ammonium hydroxide(NH_(4)OH)solution.This approach effectively stabilizes the structure during cycling,enhancing both capacity retention and conductivity.The Zn^(2+)/H+intercalation/deintercalation process was confirmed by experimental results and ex-situ X-ray diffraction analysis,which demonstrates that Mg^(2+),along with optimized NH_(4)OH amount,prevents structural collapse and improves conductivity.Under optimal process conditions,the composite electrode(Mg^(2+)-Mn_(3)O_(4)–8 ml)achieved a capacity of 173.58 mA h g^(-1) at 0.5 A g^(-1),with excellent rate performance of 71.39 mA h g^(-1) at 10 A g^(-1).Remarkably,even at 5 A g^(-1),the electrode maintained a capacity of 86.87 mA h g^(-1) over 2100 cycles,underscoring the role of Mg^(2+)and NH_(4)OH in enhancing the reversible insertion/extraction stability of Zn^(2+)in Mn-based layered materials.This study presents a novel strategy for metal-ion incorporation in Mn-based AZIBs,offering insights into the optimization of cathode materials and advancing research on associated storage mechanisms. 展开更多
关键词 Ammonia solution Metal-ion incorporation Mg^(2+)-intercalated Mn_(3)O_(4) Cathode material Aqueous zinc-ion batteries
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A technological process for extracting vanadium from leaching solution of sodium roasting of vanadium slag by manganese salt pretreatment
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作者 Mengxia Liu Tao Jiang +4 位作者 Jing Wen Zibi Fu Tangxia Yu Changqing Li Xinyu An 《Chinese Journal of Chemical Engineering》 2025年第5期219-231,共13页
The ammonium salt precipitation method is frequently utilized for extracting vanadium from the leaching solution obtained through sodium roasting of vanadium slag.However,Na^(+)and NH_(4)^(+)ions in the vanadium preci... The ammonium salt precipitation method is frequently utilized for extracting vanadium from the leaching solution obtained through sodium roasting of vanadium slag.However,Na^(+)and NH_(4)^(+)ions in the vanadium precipitation solution can not be effectively separated,leading to a large amount of ammonia-nitrogen wastewater which is difficult to treat.In this study,the manganese salt pretreatment process is used to extract vanadium from a sodium roasting leaching solution,enabling the separation of vanadium and sodium.The vanadium extraction product of manganese salt is dissolved in acid to obtain vanadium-containing leaching solution,then vanadium is extracted by hydrolysis and vanadium precipitation,and V_(2)O_(5)is obtained after impurity removal and calcination.The results show that the rate of vanadium extraction by manganese salt is 98.23%.The vanadium extraction product by manganese salt is Mn_(2)V_(2)O_(7),and its sodium content is only 0.167%.Additionally,the acid solubility of vanadium extraction products by manganese salt is 99.52%,and the vanadium precipitation rate of manganese vanadate solution is 92.34%.After the removal of manganese and calcination process,the purity of V_(2)O_(5)product reached 97.73%,with a mere 0.64%loss of vanadium.The Mn_(2)^(+)and NH_(4)^(+)ions in the solution after vanadium precipitation are separated by precipitation method,which reduces the generation of ammonia-nitrogen wastewater.This is conducive to the green and sustainable development of the vanadium industry. 展开更多
关键词 Sodium roasting leaching solution of vanadium slag Manganese salt pretreatment Acid dissolution Vanadium precipitation by hydrolysis V_(2)O_(5)
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Engineering surface and subsurface oxygen vacancies of Ce_(x)Zr_(1-x)O_(2) solid solution for enhanced total toluene oxidation
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作者 Yang Yu Mingjia Zhang +5 位作者 Huangang Shi Jifa Qu Yongheng Xiong Wenyi Tan Xinlei Ge Qijie Jin 《Journal of Environmental Sciences》 2025年第12期39-49,共11页
Most studies have shown that oxygen vacancies on Ce_(x)Zr_(1-x)O_(2) solid solution are important for enhancing the catalytic oxidation performance.However,a handful of studies investigated the different roles of surf... Most studies have shown that oxygen vacancies on Ce_(x)Zr_(1-x)O_(2) solid solution are important for enhancing the catalytic oxidation performance.However,a handful of studies investigated the different roles of surface and subsurface oxygen vacancies on the performance and mechanisms of catalysts.Herein,a series of zirconium doping on CeO_(2) samples(CeO_(2),Ce_(0.95)Zr_(0.05)O_(2),and Ce_(0.8)5Zr_(0.15)O_(2))with various surface-to-subsurface oxygen vacancies ratios have been synthesized and applied in toluene catalytic oxidation.The obtained Ce_(0.95)Zr_(0.05)O_(2) exhibits an excellent catalytic performance with a 90%toluene conversion at 295℃,which is 68℃lower than that of CeO_(2).Additionally,the obtained Ce_(0.95)Zr_(0.05)O_(2)catalyst also exhibited good catalytic stability and water resistance.The XRD and HRTEM results show that Zr ions are incorporated into CeO_(2) lattice,forming Ce_(x)Zr_(1-x)O_(2) solid solution.Temperature-programmed experiments reveal that Ce_(0.95)Zr_(0.05)O_(2) shows excellent lowtemperature reducibility and abundant surface oxygen species.In-situ DRIFTS tests were used to probe the reaction mechanism,and the function of Zr doping in promoting the activation of oxygen was further determined.Density functional theory(DFT)calculations indicate that the vacancy formation energy and O_(2) adsorption energy are both lower on Ce_(0.95)Zr_(0.05)O_(2),confirming the reason for its superior catalytic performance. 展开更多
关键词 Ce_(x)Zr_(1-x)O_(2)solid solution Toluene oxidation Surface oxygen species DFT calculations
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Effect of B_(2)O_(3) and Na_(2)B_(4)O_(7) on phosphorus enrichment in Ca_(2)SiO_(4)–Ca_(3)(PO_(4))_(2) solid solutions
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作者 Xin Ping Fang Zhang +2 位作者 Jun Peng Hong-tao Chang Shuang Liu 《Journal of Iron and Steel Research International》 2025年第6期1502-1513,共12页
To separate the phosphorus-containing phase from steel slag,the effects of B_(2)O_(3)and Na_(2)B_(4)O_(7)on the enrichment of phosphorus-containing phases in Ca_(2)SiO_(4)–Ca_(3)(PO_(4))_(2)(C_(2)S–C_(3)P)solid solu... To separate the phosphorus-containing phase from steel slag,the effects of B_(2)O_(3)and Na_(2)B_(4)O_(7)on the enrichment of phosphorus-containing phases in Ca_(2)SiO_(4)–Ca_(3)(PO_(4))_(2)(C_(2)S–C_(3)P)solid solution were comparatively analyzed through theoretical calculations and experimental investigations.The results indicate that the optimum reaction temperature between B_(2)O_(3)and C_(2)S–C_(3)P is 800℃.The phase compositions of C_(2)S–C_(3)P equilibrium system with 5 wt.%B_(2)O_(3)at 800℃ included Ca_(3)(PO_(4))_(2),CaSiO_(3)and Ca11B_(2)Si_(4)O_(22),among which the content of Ca_(3)(PO_(4))_(2)was the highest.For C_(2)S–C_(3)P with 5 wt.%Na_(2)B_(4)O_(7)equilibrium system,Ca_(3)(PO_(4))_(2),CaSiO_(3),Ca11B_(2)Si_(4)O_(22)and Na_(2)Ca_(2)P_(2)O_(8)were independent at 390–690℃.Ca_(3)(PO_(4))_(2)and Ca_(2)SiO_(4)precipitated in the solid solution when the addition of B_(2)O_(3)was more than 6 wt.%,and the content of Ca_(3)(PO_(4))_(2)raised with the increase in the addition of B_(2)O_(3).The main phases in the C_(2)S–C_(3)P solid solution with Na_(2)B_(4)O_(7)were(Ca_(2)SiO_(4))0.05[Ca_(3)(PO_(4))_(2)],Ca_(2)SiO_(4)and Na_(3)Ca_(6)(PO_(4))_(5)at 650℃.And when the addition of Na_(2)B_(4)O_(7)exceeded 6 wt.%,the content of Na_(3)Ca_(6)(PO_(4))_(5)increased significantly.There was no precipitation of Ca_(3)(PO_(4))_(2)or boron-containing phase in the samples with Na_(2)B_(4)O_(7),but a small proportion of Ca_(3)(PO_(4))_(2)transformed into(Ca_(2)SiO_(4))0.05[Ca_(3)(PO_(4))_(2)],and Ca^(2+)was partially replaced by Na^(+)to generate Na_(3)Ca_(6)(PO_(4))_(5).As a result,the temperature for Na_(2)B_(4)O_(7)to enrich the phosphorus-containing phase in C_(2)S–C_(3)P solid solution was lower than that for B_(2)O_(3).However,the grade of the phosphorus-containing phase for Na_(2)B_(4)O_(7)was lower than that for B_(2)O_(3). 展开更多
关键词 B_(2)O_(3) Na_(2)B_(4)O_(7) Ca_(2)SiO_(4)-Ca_(3)(PO_(4))_(2)solid solution Phosphorus enrichment
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Low-dose X-ray induced long afterglow NIR luminescence from Cr^(3+)doped Zn_(1-x)Cd_(x)Ga_(2)O_(4)spinel solid solutions
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作者 Tingting Zhao Wenzhi Sun +4 位作者 Shuya Wang Wei Meng Chunqing Fu Xiaoyan Fu Hongwu Zhang 《Journal of Rare Earths》 2025年第2期246-252,I0001,共8页
The low-dose X-ray induced long afterglow near infrared(NIR)luminescence from Cr^(3+)doped Zn_(1-x)Cd_(x)Ga_(2)O_(4)spinel solid solutions was investigated.The structure analysis shows the good formation of Zn_(1-x)Cd... The low-dose X-ray induced long afterglow near infrared(NIR)luminescence from Cr^(3+)doped Zn_(1-x)Cd_(x)Ga_(2)O_(4)spinel solid solutions was investigated.The structure analysis shows the good formation of Zn_(1-x)Cd_(x)Ga_(2)O_(4)spinel solid solutions,which possesses a cubic spinel structure with Fd3m space group.The formation of Zn_(1-x)Cd_(x)Ga_(2)O_(4)spinel solid solutions induces the obvious increase of long afterglow near infrared luminescence excited by low-dose X-ray,When the content of doped Cd^(2+)reaches 0.1,the low-dose X-ray induced long afterglow NIR luminescence is the maximum.More importantly,only 5 s Xray irradiation can induce more than 6 h NIR afterglow emission,of which the afterglow luminescent intensity is still 5 times stronger than the background intensity after 6 h.The thermoluminescent results show that under the 5 s exposure of X-ray,the trap density of Zn_(0.9)Cd_(0.1)Ga_(2)O_(4):Cr^(3+)is much higher than that of ZnGa_(2)O_(4):Cr^(3+).The replacement of Cd^(2+)ions with large radius at Zn^(2+)sites causes the increase of de fects and dislocations,which results in the obvious increase of trap co ncentrations.And the addition of high-z number elements Cd^(2+)would enhance the X-ray absorption of the solid solutions,which thus can be easily excited by low-dose X-ray.Zn_(0.9)Cd_(0.1)Ga_(2)O_(4):1%Cr^(3+)solid solution is a potential candidate of lowdose X-ray induced long afterglow luminescent materials. 展开更多
关键词 Zn_(1-x)Cd_(x)Ga_(2)O_(4):1%Cr^(3+) Phosphors Solid solutions X-ray induced long afterglow luminescence Rare earths
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电镀实验的理论分析与教学建议——探究铁钉镀铜实验中电镀液的选择
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作者 温利权 安德成 刘红云 《化学教育(中英文)》 北大核心 2026年第3期89-94,共6页
简单的电镀实验是高中学生必做实验,教材在“铁钉镀铜”实验中以CuSO_(4)溶液为电镀液,并未明确说明能否选择Cu(NO_(3))_(2)或CuCl_(2)等其他铜盐溶液作为电镀液。实验发现,如果使用CuCl_(2)或Cu(NO_(3))_(2)作为电镀液,电解过程中均存... 简单的电镀实验是高中学生必做实验,教材在“铁钉镀铜”实验中以CuSO_(4)溶液为电镀液,并未明确说明能否选择Cu(NO_(3))_(2)或CuCl_(2)等其他铜盐溶液作为电镀液。实验发现,如果使用CuCl_(2)或Cu(NO_(3))_(2)作为电镀液,电解过程中均存在副反应,不适宜用作课堂演示实验;若使用铜氨溶液作为电镀液,不仅可使生成的铜镀层致密光亮,还可避免铁电极腐蚀。但文献调研发现,生产实际中则需用Cl-作为电镀液的添加剂或使用Cu(NO_(3))_(2)作为精炼铜的电解液。因此课堂教学中教师应注意知识在不同阶段的局限性和适用性,悉心引导学生关注具体实验条件对实验结果的影响、关注具体实践要求下的条件选择。 展开更多
关键词 电镀 铁钉镀铜 硝酸铜 氯化铜 铜氨溶液
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3-氯-2-氟苯磺酰胺合成与纯化
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作者 周永生 单凯 +1 位作者 方建波 顾浩 《广东化工》 2026年第4期29-31,59,共4页
以稀氨水和3-氯-2-氟苯磺酰氯混合液作为底液,向底液中滴加26.5%的氨水,制备3-氯-2-氟苯磺酰胺(CFBS)粗品,考察反应时间、反应温度和底液pH值对粗品收率的影响。再分别采用冷却结晶法和溶剂析出法对粗品进行纯化,对两种工艺进行了对比... 以稀氨水和3-氯-2-氟苯磺酰氯混合液作为底液,向底液中滴加26.5%的氨水,制备3-氯-2-氟苯磺酰胺(CFBS)粗品,考察反应时间、反应温度和底液pH值对粗品收率的影响。再分别采用冷却结晶法和溶剂析出法对粗品进行纯化,对两种工艺进行了对比。结果表明,在反应温度50℃、反应时间60 min、底液pH=10.9条件下,所得粗品纯度最好(92.8%),收率最高(86.6%);以乙醇为溶剂对粗品进行四步冷却结晶,所得产品纯度最好(99.8%),收率最高(95.0%)。本工艺所制得产品纯度好、收率高,溶剂可回收利用,对环境友好。 展开更多
关键词 3-氯-2-氟苯磺酰胺 底液 合成 冷却结晶 纯化
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模糊差分方程X_(n+1)=δ_(n)+(X_(n))/(X_(n-1))的动力学性质
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作者 张更容 袁美兰 《安徽大学学报(自然科学版)》 北大核心 2026年第1期1-9,共9页
差分方程作为动力系统重要分支之一,一直以来都受到学术界的广泛关注.近年来,由于在应用差分方程解决实际问题时,参数的波动和变化带来了方法的转变,故模糊差分方程的研究引起了该领域众多学者的关注.论文中模糊差分方程X_(n+1)=δ_(n)+... 差分方程作为动力系统重要分支之一,一直以来都受到学术界的广泛关注.近年来,由于在应用差分方程解决实际问题时,参数的波动和变化带来了方法的转变,故模糊差分方程的研究引起了该领域众多学者的关注.论文中模糊差分方程X_(n+1)=δ_(n)+(X_(n))/(X_(n-1)),n=0,1,2,…的动力学性质将被展开讨论,其中,初始条件X_(-1),X_(0)是正模糊数,参数δn是2周期正模糊数序列.研究得到,该模糊差分方程存在唯一正解X_(n),且每一正解都收敛于唯一的2周期解. 展开更多
关键词 模糊差分方程 存在性 唯一性 2周期解 全局渐近稳定性
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补肾止颤方对帕金森病模型大鼠多巴胺能神经元铁死亡及Nrf2调控SLC7A11/GSH/GPX4信号通路的影响
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作者 胡玉英 陈伟营 +3 位作者 宋曦 黎晓东 刘姗姗 罗智慧 《中医杂志》 北大核心 2026年第2期188-195,共8页
目的从铁死亡角度探讨补肾止颤方治疗帕金森病(PD)的可能作用机制。方法70只SD大鼠随机分为对照组、模型组、核转录因子E2相关因子2(Nrf2)抑制剂组、多巴丝肼组及补肾止颤方低、中、高剂量组,每组10只。除对照组外,其余各组大鼠采用蛋... 目的从铁死亡角度探讨补肾止颤方治疗帕金森病(PD)的可能作用机制。方法70只SD大鼠随机分为对照组、模型组、核转录因子E2相关因子2(Nrf2)抑制剂组、多巴丝肼组及补肾止颤方低、中、高剂量组,每组10只。除对照组外,其余各组大鼠采用蛋白酶抑制因子皮下注射建立PD大鼠模型。造模2周后,Nrf2抑制剂组大鼠予ML385小分子化合物50 mg/kg腹腔注射,隔日1次,共3次,其余各组大鼠于同时间点予2 ml/kg生理盐水腹腔注射。造模4周后,补肾止颤方低、中、高剂量组分别给予补肾止颤方颗粒剂溶液1.0、1.5、2.0 ml/(100 g·d)灌胃,多巴丝肼组则予多巴丝肼片200 mg/(100 g·d)灌胃,对照组、模型组、Nrf2抑制剂组大鼠均以生理盐水按2.0 ml/(100 g·d)灌胃。各组大鼠灌胃3周后,采用网格实验、爬杆实验进行行为学检测,对PD大鼠的运动功能进行评估;采用qRT-PCR法检测大鼠中脑黑质Nrf2 mRNA表达,Western Blot法检测Nrf2、溶质载体家族7成员(SLC7A11)、谷胱甘肽过氧化物酶4(GPX4)蛋白水平,ELISA法检测谷胱甘肽(GSH)、丙二醛(MDA)含量、亚铁离子(Fe^(2+))、GPX4含量,荧光酶标仪检测活性氧(ROS)水平。结果与对照组比较,模型组大鼠网格实验移动潜伏期、爬杆时间均增加,中脑黑质区GSH、GPX4含量降低,Fe^(2+)、MDA含量升高,Nrf2、SLC7A11、GPX4蛋白水平均降低,ROS水平升高,Nrf2 mRNA表达下降(P<0.05);Nrf2抑制剂组上述各指标与模型组变化趋势相同,且程度较模型组更显著,与模型组、对照组比较差异均有统计学意义(P<0.05)。与模型组比较,多巴丝肼组和补肾止颤方低、中、高各剂量组各指标均改善(P<0.05),且补肾止颤方高剂量组和多巴丝肼组各指标均较补肾止颤方低、中剂量组改善更为显著(P<0.05);补肾止颤方高剂量组和多巴丝肼组改善情况差异均无统计学意义(P>0.05)。结论补肾止颤方可能通过激活中脑黑质Nrf2表达,调控SLC7A11/GSH/GPX4信号通路,从而抑制脂质过氧化和铁死亡,达到治疗PD的目的。 展开更多
关键词 帕金森病 铁死亡 补肾止颤方 脂质过氧化 核转录因子E2相关因子2 溶质载体家族7成员 谷胱甘肽 谷胱甘肽过氧化物酶4
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Selective recovery of lead from zinc oxide dust with alkaline Na_2EDTA solution 被引量:8
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作者 刘青 杨声海 +2 位作者 陈永明 何静 薛浩天 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1179-1186,共8页
The selective recovery of lead from the zinc oxide dust using an alkaline Na2EDTA solution was investigated. The effects of temperature, leaching time, Na2EDTA concentration and initial NaOH concentration on the leach... The selective recovery of lead from the zinc oxide dust using an alkaline Na2EDTA solution was investigated. The effects of temperature, leaching time, Na2EDTA concentration and initial NaOH concentration on the leaching rates of lead and zinc were studied. The following optimized leaching conditions were obtained: liquid-to-solid ratio 5:1 mL/g, stirring speed 650 r/min, Na2EDTA concentration 0.12 mol/L, initial NaOH concentration 0.5 mol/L, leaching temperature 70 ℃, leaching time 120 min. Under the optimized conditions, the average leaching rates of lead, zinc, fluoride and chloride are 89.92%, 0.94%, 62.84% and 90.02%, respectively. The filtrate was used to electrowin lead powders. The average current efficiency of electrowinning is about 93% and lead content is higher than 98% under the conditions of temperature of 60 ℃, current density of 200 A/m2, H3PO4 concentration of 1.5 g/L, and lead ion concentration of above 5 g/L. The consumption of Na2EDTA and the direct current are about respectively 0.218 kg and 0.958 kW·h for per kilogram of lead powder. 展开更多
关键词 LEAD zinc oxide dust alkaline Na2EDTA solution ELECTROWINNING LEACHING
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Removal of S^(2-) ion from sodium aluminate solutions with sodium ferrite 被引量:4
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作者 李小斌 牛飞 +4 位作者 谭杰 刘桂华 齐天贵 彭志宏 周秋生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第5期1419-1424,共6页
The synthesis of sodium ferrite and its desulfurization performance in S2 -bearing sodium aluminate solutions were investigated. The thermodynamic analysis shows that the lowest temperature is about 810 K for synthesi... The synthesis of sodium ferrite and its desulfurization performance in S2 -bearing sodium aluminate solutions were investigated. The thermodynamic analysis shows that the lowest temperature is about 810 K for synthesizing sodium ferrite by roasting the mixture of ferric oxide and sodium carbonate. The results indicate that the formation process of sodium ferrite can be completed at 1173 K for 60 min, meanwhile raising temperature and reducing NazCO3 particle size are beneficial to accelerating the formation of sodium ferrite. Sodium ferrite is an efficient desulfurizer to remove the S2- in aluminate solution, and the desulfurization rate can reach approximately 70% at 373 K for 60 min with the molar ratio of iron to sulfur of 1:1-1.5:1. Furthermore, the desulfurization is achieved by NaFeS2·2H2O precipitation through the reaction of Fe(OH)4 and S^2- in aluminate solution, and the desulfurization efficiency relies on the Fe(OH)4^- generated by dissolving sodium ferrite. 展开更多
关键词 sodium ferrite S^2- sodium aluminate solution DESULFURIZATION
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Measurements of zinc oxide solubility in sodium hydroxide solution from 25 to 100 °C 被引量:3
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作者 陈爱良 徐冬 +2 位作者 陈星宇 张文勇 刘旭恒 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第6期1513-1516,共4页
The solubility of zinc oxide in sodium hydroxide solution was measured in a closed polytetrafluoroethylene vessel from 25 to 100 ℃. The ZnO solubility was determined by employing the method of isothermal solution sat... The solubility of zinc oxide in sodium hydroxide solution was measured in a closed polytetrafluoroethylene vessel from 25 to 100 ℃. The ZnO solubility was determined by employing the method of isothermal solution saturation. The results show that only ZnO solid exists in the equilibrium state in the low concentration alkali regions, and the solubility of zinc oxide is almost invariable with temperature. With the increase of alkali concentration, equilibrium solid turns from ZnO to NaZn(OH)3 suddenly, this mutation is called invariant point. The alkali concentration of the invariant points increases with increasing temperature, but the solubility of NaZn(OH)3 decreases with increasing alkali concentration at the same temperature. At the same Na2O concentration, the higher the temperature is, the higher the solubility of NaZn(OH)3 is. 展开更多
关键词 ZnO solubility sodium hydroxide solution Na2O-ZnO-H2O system equilibrium phase diagram
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Influence of solution treatment on microstructure and properties of in-situ Mg_2Si/AZ91D composites 被引量:4
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作者 彭蕾 陈刚 +2 位作者 赵玉涛 黄康 邵阳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2365-2371,共7页
The influence of solution treatment on the microstructure and properties of Mg2Si/AZ91D composites fabricated from Mg-SiO2 system via in-situ processing method was investigated.The results show that coarse Chinese scr... The influence of solution treatment on the microstructure and properties of Mg2Si/AZ91D composites fabricated from Mg-SiO2 system via in-situ processing method was investigated.The results show that coarse Chinese script shape Mg2Si phases can be formed by adding SiO2 into AZ91D magnesium alloy with Si content up to 1.5% of the alloy melt.During solution treatment,the morphology and distribution of the coarse Chinese script shape Mg2Si phases are modified.Meanwhile,the β-Mg17Al12 phase is dissolved into the magnesium matrix.With increasing holding time,the coarse Mg2Si phases tend to dissolve,break and spheroidize.After solution treatment at 420 ℃ for 16 h,Mg2Si phases become the finest and relatively well-distributed phase.The tensile strength and elongation are increased by 14.9% and 38.9%,respectively.It is believed that the Mg2Si phases continuously dissolve and break,and finally the spheroidized Mg2Si particles are obtained due to the interface tension of Mg2Si/Mg interface. 展开更多
关键词 Mg2Si/AZ91D composites solution treatment spheroidized Mg2Si particle interface tension
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