检索结果-南通市图书馆

HIGH-TEMPERATURE Ac MAGNETIc PROPERTIES OF NANOcRySTALLINE FINEMET ALLOyS WITH co ADDITION

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2007年第5期20卷 327-333页

作者： y.H. Ding X. liu S.S. Zhao y. Long R.c. ye y.Q. chang F.R. Wan School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China college of Science Tianjin University of Technology Tianjin 300191 China

High-temperature Ac magnetic properties for （Fe0.5co0.5）73.5cu1Nb3Si13.5B9 alloy annealed at various temperatures have been investigated using an impedance analyzer. Annealing temperature Ta has obvious effects on high-temperature Ac magnetic properties of the alloy. The Hopkinson peak appears only in the amorphous alloy when Ta≤703K. As Ta increases above 733K, the real part of the complex initial permeability μi′descends gradually, μi′decreases more slowly with temperature in the high temperature range. The high-temperature （about 750K） Ac initial permeability for the alloy annealed at Ta= 763K has been found to maintain a stable high value of 950 up to a frequency of- 1 × 10^5Hz. Partial substitution of co for Fe in the F73.5cu1Nb3Si13.5B9 alloy leads to an increase of around 110K of the curie temperature of the amorphous phase, much higher than Ge-containing Finemet alloy.

关键词： high temperature nanocrystalline permeability spectra

The Development of a Renewable-Energy-Driven Reverse Osmosis System for Water Desalination and Aquaculture Production

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2013年第8期12卷 1357-1362页

作者： clark c K liu Department of civil and Environmental Engineering and Water Resources Research CenterUniversity of Hawaii at Manoa

Water and energy are closely linked natural resources - the transportation, treatment, and distribution of water depends on low-cost energy; while power generation requires large volumes of water. Seawater desalination is a mature technology for increasing freshwater supply, but it is essentially a trade of energy for freshwater and is not a viable solution for regions where both water and energy are in short supply. This paper discusses the development and application of a renewable-energy-driven reverse osmosis （RO） system for water desalination and the treatment and reuse of aquaculture wastewater. The system consists of （1） a wind-driven pumping subsystem, （2） a pressure-driven RO membrane desalination subsystem, and （3） a solar-driven feedback control module. The results of the pilot experiments indicated that the system, operated under wind speeds of 3 m s-~ or higher, can be used for brackish water desalination by reducing the salinity of feedwater with total dissolved solids （TDS） of over 3 000 mg L-1 to product water or permeate with a TDS of 200 mg L-~ or less. Results of the pilot experiments also indicated that the system can remove up to 97% of the nitrogenous wastes from the fish pond effluent and can recover and reuse up to 56% of the freshwater supply for fish pond operation.

关键词： renewable energy desalination pressure-driven membrane processes aquaculture fish pond

Overcoming the strength-ductility trade-off by tailoring grain-boundary metastable Si-containing phase in β-type titanium alloy

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第9期68卷 112-123页

作者： X.Luo L.H.liu c.yang H.Z Lu H.W.Ma Z.Wang D.D.Li L.c.Zhang y.y.Li National Engineering Research center of Near-net-shape Forming for Metallic Materials South China University of TechnologyGuangzhou510640China State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China Key Laboratory of Automobile Materials of MOE Department of Materials ScienceJilin UniversityChangchun130012China School of Engineering Edith Cowan University270Joondalup DriveJoondalupPerthWA 6027Australia

It is well accepted that grain-boundary phases in metallic alloys greatly deteriorate the mechanical *** our work,we report on a novel strategy to prepare high strength-ductility β-type(Ti69.71 Nb23.72Zr4.83Ta1.74)97Si3(at.%)(TNZTS) alloys by tailoring grain-boundary metastable Si-containing ***,the thin shell-shaped metastable S1 phase surrounding the columnar β-Ti grain was intercepted successfully via nonequilibrium rapid solidification achieved by selective laser melting(SLM).Subsequently,the thin shell-shaped metastable(Ti,Nb,Zr)5 Si3(called S1) phase was transformed into globular(Ti,Nb,Zr)2 Si(called S2) phase by the solution heat ***,the globular S2 phases reinforced TNZTS alloy exhibits ultrahigh yield strength of 978 MPa,ultimate strength of 1010 MPa and large elongation of 10.4 %,overcoming the strength-ductility trade-off of TNZTS alloys by various ***,the reported yield strength herein is 55 % higher than that of conventionally forged TNZT *** analysis indicates the globularization process of the metastable S1 phase is controlled by the model of termination *** quantitative analysis on strengthening mechanism demonstrates that the increase in yield strength of the heat-treated alloys is mainly ascribed to the strengthening of the precipitated silicide and the dislocations induced by high cooling *** obtained results provide some basis guidelines for designing and fabricating β-titanium alloys with excellent mechanical properties,and pave the way for biomedical application of TNZTS alloy by SLM.

关键词： Selective laser melting βtitanium alloys Heat treatment

carbon-supported ceNcl as an efficient catalyst for cO_(2)cycloaddition

在线全文

学校读者我要写书评

暂无评论

Nano Research 2025年第1期18卷 157-163页

作者： Li liu Lingling Zhang Xiang chu Baokang Geng Huilin Wang Zongxiang Li Xiao Wang Shuyan Song Hongjie Zhang School of Applied chemistry and Engineering University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Sinocare Incorporation Changsha 410221China Department of chemistry Tsinghua UniversityBeijing 100084China

The cycloaddition reaction of cO_(2)with epoxide not only effectively reduces the concentration of cO_(2)in the atmosphere,but also has excellent industrial application value and up to 100%atom utilization,but there are difficulties in separation and recovery of traditional homogeneous catalysts,harsh reaction conditions of traditional heterogeneous catalysts,and activation of cO_(2)*** this paper,an easily synthesized heterogeneous catalyst ceNcl/c was used to catalyze the cycloaddition reaction of cO_(2)with styrene oxide,with a high yield of 92.7%,a high selectivity of 96.7%,a turnover numbers(TON)value of 349,and a good stability demonstrated in six cycle tests(equivalent to 216 h of testing).Through comprehensive studies,it was shown that ceNcl/c contains Lewis acid-base centers as active centers,which can effectively reduce the energy barrier required for ring opening of the reaction substrate,enhance the adsorption and activation of cO_(2),and promote the formation of intermediates,which led to the acquisition of excellent catalytic activity.

关键词： cO_(2)cycloaddition heterogeneous catalysis ceNcl Lewis acid/base

Pinless Friction Stir Spot Welding of Mg-3Al-1Zn Alloy with Zn Interlayer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2016年第1期32卷 76-88页

作者： R.Z.Xu D.R.Ni Q.yang c.Z.liu Z.y.Ma college of Materials Science and Engineering Shenyang Aerospace University Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

With the addition of a thin Zn interlayer, 2.4 mm thick Mg-3AI-1Zn alloy sheets were friction stir spot welded （FSSW） using a pinless tool with fiat, convex and concave shoulder shapes. The results showed that an alloying reaction took place between the Mg substrate and Zn interlayer during FSSW, forming a discontinuous intermetallics layer composed of dispersive （α-Mg ＋ MgZn） eutectic structure under- neath the shoulder and a Mg-Zn intermetallics bonding zone at the outside of the joints. This alloying reaction increased the bonded area and eliminated the hook defects, thereby producing sound FSSWjoints with a shallow keyhole without hook defects. The increase of plunge depth was beneficial to the Mg-Zn diffusion, thereby increasing the tensile-shear load of the joints. However, excessive plunge depths re- sulted in a decrease of the effective sheet thickness, reducing the strength of the joints. At a small plunge depth, the convex and concave shoulders were more beneficial to the interface reaction than the fiat shoul- der. The maximum joint load of 6.6 kN was achieved by using the concave shoulder at a plunge depth of 1.0 mm. A post-welding heat treatment promoted the dissolution of the discontinuous reaction layer in the joints; however, it led to the occurrence of void defects, influencing the bonding strength.

关键词： Friction stir spot welding Magnesium alloys Zn interlayer Hook defects

Spectral measurements of hypervelocity flow in an expansion tunnel

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2019年第1期35卷 24-31,I0002页

作者： c.K.yuan K.Zhou y.F.liu Z.M.Hu Z.L.Jiang State Key Laboratory of High-Temperature Gas Dynamic Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences. University of chinese Academy of Sciences Beijing 100049China china Academy of Aerospace Aerodynamics Beijing 100074China

Atmospheric reentry vehicles and planetary probes fly through the atmosphere at hypervelocity speed. At such speed, there is a significant proportion of heat load to the vehicle surface due to radiative heating. Accurate prediction needs a good knowledge of the radiation spectrum properties. In this paper, a high-speed camera and spectrograph coupled to an intensified charge-coupled device have bee n impleme nted to inv estigate the rad i at io n flow over a semi-cylinder model. The experiments were carried out in the JF16 expansi on timnel with secondary shock velocity of 7.9 km·s^-1. Results show that the emissio n spectrum comprises several atomic lines and molecular band systems. We give detailed data of the radiation spectrum, shock shape, shock detached distance and radiation intensity varying with space and wavelength. This valuable experimental dataset will be helpful to validate computational fluid dynamics codes and radiation models, which equates to increased prediction accuracy of radiation heating. Also, some suggestions for spectral measurement in hypervelocity flow field were list in the end.

关键词： Spectral measurement Hypervelocity flow Radiation Expansion tunnel

Fabrication of carbon-supported Al2O3 nanoparticles via spontaneous cross-linking to enhance selective hydrogenation of furfural

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy.c.emistry 2025年第1期100卷 612-620页

作者： Weiwei yu Xinbao Zhang Hongyu chen yanan Wang Shaoguo Li Fucun chen Zhenni liu Xiujie Li Xiangxue Zhu State Key Laboratory of catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of c=c over c=***,a novel Al2O3/c-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al2O3nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and *** obtained carbon-supported Al2O3hybrid catalyst has a high ratio （31%） of Al species in pentahedral-coordinated *** introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of c=O and the accessibility of active *** the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al2O3/c-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-***,Al2O3/c-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on *** work provides an innovative and facile strategy for fabrication of carbon-supported Al2O3hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route.

关键词： Selective hydrogenation Furfural Furfuryl alcohol cross-linking MPV route

Hydrogen-bonded organic framework-ionic liquid composite quasisolid electrolyte for high-performance lithium battery

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2025年第1期18卷 332-340页

作者： Junmei Zhang yatao Wu chenye Wang yong liu Zhirong yang Shiyue Zhou Wenpeng Li Wenjia Wu Jingtao Wang School of chemical Engineering Zhengzhou UniversityZhengzhou 450001China

Ionic liquids(ILs)hold great promise as highperformance electrolyte material due to their unique advantages including nonvolatility,high thermal stability and high ionic ***,the IL-based electrolytes always suffer from serious ion aggregation and high viscosity at low temperatures,leading to significantly decline in ionic ***,hydrogen-bonded organic framework-ionic liquid composite quasi-solid electrolyte(high temperature treatment(HT)-HOF-IL cQSE)was prepared through confining the IL electrolytes(ILEs)into the pore of HOF lamellar *** weak hydrogen bonding interactions within HOF nanosheets,together with the generated interactions between ILE and HOF,enable uniform and continuous distribution of ILE in HOF lamellar *** effectively inhibits the ion migration of ILE,which meanwhile serves as Li+transfer sites,affording high ionic conductivity of 5.7×10^(-5)S·cm-1 at-60 ℃,with high lithium-ion transference number of 0.69,whereas ILEs usually lose ionic conduction ability at such low *** assembled Li symmetrical cell can stably.c.cle at 0.2 mA·cm^(-2)and^(-2)0 ℃ for more than 1500 *** LiFePO_(4)|HT-HOF-IL cQSE|Li cell shows excellent cycling performance at 0.5 c at a wide temperature range of^(-2)0 to 60 ℃.This work may pave a new avenue for the development of high-performance IL-based composite electrolytes.

关键词： ionic liquid hydrogen-bonded organic framework low-temperature ionic conductivity lithium-ion transference number quasi-solid electrolyte

Engineering of Fe d-band center in Fe_(3)O_(4)/ceO_(2)hetero-nanoparticles via orbital coupling for high-efficiency oxygen reduction electrocatalysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2025年第1期18卷 129-139页

作者： Jiayi liu Jingwen yin yingzi Lin Mingxin Pang Huan Pang Songtao Zhang Lin Xu Jun yang yawen Tang Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Center of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023Chin a 2 State Key Laboratory of Multiphase complex Systems Center of MesoscienceInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of chemistry and chemical Engineering Yangzhou UniversityYangzhou 225009China Testing center Yangzhou UniversityYangzhou 225009China

The deliberate engineering of the d-band center of metal site represents an effective strategy to boost the intrinsic electrocatalytic performance toward the oxygen reduction reaction(ORR).Herein,following a heterointerfaceinduced orbital coupling rationale,we report a judicious design of an efficient ORR electrocatalyst consisting of Fe_(3)O_(4)/ceO_(2)hetero-nanoparticles in-situ encased into N-doped carbon nanofibers(abbreviated as Fe_(3)O_(4)/ceO_(2)@N-cNFs hereafter).The theoretic calculations uncover that the Fe_(3)O_(4)/ceO_(2)heterointerface-triggered orbital coupling can cause the down shift of the d-band center positions of Fe sites,which leads to the weakened chemisorption of oxygenated groups and lowered energy barrier for the potential-determining step,ultimately dramatically boosting the ORR intrinsic *** a consequence,the well-designed Fe_(3)O_(4)/ceO_(2)@N-cNFs display admirable ORR activity with a half-wave potential of 0.84 V and outstanding structural/electrochemical stability in an alkaline electrolyte,surpassing the commercial Pt/c benchmark and a majority of recently reported Fe_(3)O_(4)-based *** encouragingly,the Fe_(3)O_(4)/ceO_(2)@N-cNFsincorporated Zn-air battery outperforms the Pt/c-assembled counterpart with higher power density,larger energy density,and excellent cycling stability,serving as a competent candidate for ORR-involved renewable energy *** study offers an innovative approach for the rational manipulation of the d-band center and interfacial electron behavior of active sites toward the optimization of electrocatalytic performance.

关键词： hetero-nanoparticles electrospinning interfacial engineering orbital coupling oxygen reduction reaction