|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Tribological properties of copper matrix composites reinforced with homogeneously dispersed graphene nanosheets显示文摘Graphene reinforced copper matrix composites(Gr/Cu) were fabricated by electrostatic self-assembly and powder metallurgy. The morphology and structure of graphene oxide, graphene oxide-Cu powders and Gr/Cu composites were characterized by scanning electronic microscopy, transmission electronic microscopy, X-ray diffraction and Raman spectroscopy, respectively. The effects of graphene contents,applied loads and sliding speeds on the tribological behavior of the composites were investigated. The results indicate that the coefficient of friction of the composites decreases first and then increases with increasing the graphene content. The lowest friction coefficient is achieved in 0.3 wt% Gr/Cu composite,which decreases by 65% compared to that of pure copper. The coefficient of friction of the composite does not have significant change with increasing the applied load, however, it increases with increasing the sliding speed. The tribological mechanisms of the composite under different conditions were also investigated. | Xin Gao Hongyan Yue Erjun Guo Shaolin Zhang Longhui Yao Xuanyu Lin Bao Wang Enhao Guan | 2018 | Journal of Materials Science & Technology2018,34,10: | 9 |
| 2 | Research on microstructure in as-cast 7A55 aluminum alloy and its evolution during homogenization显示文摘The microstructure of the as-cast 7A55 aluminum alloy and its evolution during homogenization were investigated by means of optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and differential scanning calorimetry (DSC) analysis. The results indicate that the microstructure of the as-cast 7A55 aluminum alloy mainly consists of the dendritic network of aluminum solid solution, Al/AlZnMgCu eutectic phases, and intermetallic compounds MgZn2, Al2CuMg, Al7Cu2Fe, and Al23CuFe4. After homogenization at 470°C for 48 h, Al/AlZnMgCu eutectic phases are dissolved into the matrix, and a small amount of high melting-point secondary phases were formed, which results in an increasing of the starting melting temperature of 7A55 aluminum alloy. The high melting-point secondary phases were eliminated mostly when the homogenization time achieved to 72 h. Therefore, the reasonable homogenization heat treatment process for 7A55 aluminum alloy ingots was chosen as 470°C/72 h. | LV Xinyu GUO Erjun LI Zhihui WANG Guojun | 2011 | Rare Metals2011,30,6: | 8 |
| 3 | Physical modeling of spent-nuclearfuel container显示文摘A new physical simulation model was developed to simulate the casting process of the ductile iron heavy section spent-nuclear-fuel container.In this physical simulation model,a heating unit with DR24 Fe-Cr-Al heating wires was used to compensate the heat loss across the non-natural surfaces of the sample,and a precise and reliable casting temperature controlling/monitoring system was employed to ensure the thermal behavior of the simulated casting to be similar to the actual casting.Also,a mould system was designed,in which changeable mould materials can be used for both the outside and inside moulds for different applications.The casting test was carried out with the designed mould and the cooling curves of central and edge points at different isothermal planes of the casting were obtained.Results show that for most isothermal planes,the temperature control system can keep the temperature differences within 6 ℃ between the edge points and the corresponding center points,indicating that this new physical simulation model has high simulation accuracy,and the mould developed can be used for optimization of casting parameters of spent-nuclear-fuel container,such as composition of ductile iron,the pouring temperature,the selection of mould material and design of cooling system.In addition,to maintain the spheroidalization of the ductile iron,the force-chilling should be used for the current physical simulation to ensure the solidification of casting in less than 2 h. | Wang Liping Guo Erjun Jiang Wenyong Xue Muyu Liu Dongrong Ren Shanzhi | 2012 | China Foundry2012,9,4: | 5 |
| 4 | Tuning the intermolecular interaction of A_(2)-A_(1)-D-A_(1)-A_(2) type non-fullerene acceptors by substituent engineering for organic solar cells with ultrahigh V_(OC) of ~1.2 V显示文摘For non-fullerene acceptors(NFAs)with linear A_(2)-A_(1)-D-A_(1)-A_(2) backbone,there are three kinds of possible intermolecular interaction,A_(1)-A_(1),A_(1)-A_(2) and A_(2)-A_(2) stacking.Hence,it is a huge challenge to control this interaction and investigate the effect of intermolecular stacking model on the photovoltaic performance.Here,we adopt a feasible strategy,by utilizing different substituent groups on terminal A2 unit of dicyanomethylene rhodanine(RCN),to modulate this stacking model.According to theoretical calculation results,the molecule BTA3 with ethyl substituent packs via heterogeneous interaction between A_(2) and A_(1) unit in neighboring molecules.Surprisingly,the benzyl group can effectively transform the aggregation of BTA5 into homogeneous packing of A_(2)-A_(2) model,which might be driven by the strong interaction between benzyl and A1(benzotriazole)unit.However,different with benzyl,phenyl end group impedes the intermolecular interaction of BTA4 due to the large steric hindrance.When using a BTA-based D-π-A polymer J52-F as donor according to“Same-A-Strategy”,BTA3-5 could achieve ultrahigh open-circuit voltage(VOC)of 1.17–1.21 V.Finally,BTA5 with benzyl groups realized an improved power conversion efficiency(PCE)of 11.27%,obviously higher than that of BTA3(PCE=9.04%)and BTA4(PCE=5.61%).It is also worth noting that the same trend can be found when using other four classic p-type polymers of P3HT,PTB7,PTB7-Th and PBDB-T.This work not only investigates the intermolecular interaction of A_(2)-A_(1)-D-A_(1)-A_(2) type NFAs for the first time,but also provides a straightforward and universal method to change the interaction model and improve the photovoltaic performance. | Xiaochen Wang Ailing Tang Jing Yang Mengzhen Du Jianfeng Li Gongqiang Li Qiang Guo Erjun Zhou | 2020 | Science China Chemistry2020,63,11: | 5 |
| 5 | Rotary impeller refinement of 7075Al alloy显示文摘The effects of four parameters, gas flow, rotational speed, refining time, and stewing time, on the rotary impeller refinement of 7075 Al were studied. The effects of C2Cl6 refining, rotary impeller refining, and composite refining of 7075 Al alloy were compared with each other. The results showed that the greatest impact parameter of rotary impeller refinement was rotational speed, followed by gas flow, refining time, and stewing time. The optimum purification parameters obtained by orthogonal analysis were as follows: rotor speed of 400 r/min, inert gas flow of 0.4 mL/h, refining time of 15 min, and stewing time of 6 min. The best degassing effect can be obtained by the composite refining of C2Cl6 and rotary impeller. The degassing rate of C2Cl6, rotary impeller, and composite refining was 34.5%, 69.2%, and 78%, respectively. The mechanical properties of the specimen refined by rotary impeller were higher than those by C2Cl6 refining, but lower than those by composite refining. | WANG Liping GUO Erjun HUANG Yongchang LU Bin | 2009 | Rare Metals2009,28,3: | 4 |
| 6 | Effect of Bi on graphite morphology and mechanical properties of heavy section ductile cast iron显示文摘To improve the mechanical properties of heavy section ductile cast iron, bismuth(Bi) was introduced into the iron. Five castings with different Bi content from 0 to 0.014 wt.% were prepared; and four positions in the casting from the edge to the center, with different solidifi cation cooling rates, were chosen for microstructure observation and mechanical properties test. The effect of the Bi content on the graphite morphology and mechanical properties of heavy section ductile cast iron were investigated. Results show that the tensile strength, elongation and impact toughness at different positions in the fi ve castings decrease with a decrease in cooling rate. With an increase in Bi content, the graphite morphology and the mechanical properties at the same position are improved, and the improvement of mechanical properties is obvious when the Bi content is no higher than 0.011wt.%. But when the Bi content is further increased to 0.014wt.%, the improvement of mechanical properties is not obvious due to the increase of chunky graphite number and the aggregation of chunky graphite. With an increase in Bi content, the tensile fracture mechanism is changed from brittle to mixture ductile-brittle fracture. | Song Liang Guo Erjun Tan Changlong | 2014 | China Foundry2014,11,2: | 4 |
| 7 | Effects of RE,V,Ti and B composite modification on the microstructure and properties of high chromium cast iron containing 3% molybdenum显示文摘The effects of RE, V, Ti and B on the microstructure and properties of high chromium cast iron containing 3% molybdenum under as-cast and heat treatment conditions were investigated with the method of comparing experiments. The results show that with the increase of RE content, the primary austenite of high chromium cast iron is obviously refined. The morphology of carbide is changed from netlike and lath to small multiangular isolated blocks or massive blocks, the isolated degree of carbide is improved obviously, and the size is significantly refined. The addition of V and B into high chromium cast iron can refine the microstructure, reduce coarse columnar crystals and make the carbide smaller and uniform. Through composite modification with RE, V, Ti and B, the hardness, wear resistance and impact toughness of high chromium cast iron are increased conspicuously. After heat treatment, the hardness of high chromium iron is increased significantly, but the toughness and wear resistance do not show great improvement. | GUO Erjun WANG Lihua WANG Liping HUANG Yongchang | 2009 | Rare Metals2009,28,6: | 4 |
| 8 | Influences of different degassing processes on refining effect and properties of 4004 Al alloy显示文摘In order to improve the plasticity of 4004 Al alloy and subsequently the productivity of 4004 Al foil, the research studied in detail the influence of the rotary impeller degassing process on the refining effect of 4004 Al alloy, in which the impacts of four major parameters: gas flow, rotational speed, refining time, and stewing time, on degassing rate of 4004 Al alloy was systematically studied by using an orthogonal experiment methodology. Results show that the rotational speed has the greatest impact on the degassing of 4004 Al alloy, followed by gas flow and refining time; stewing time has the least impact. The optimum purification parameters obtained by current orthogonal analysis were: rotor speed of 500 r·min-1, inert gas flow of 0.4 mL·h-1, refining time of 15 min, and stewing time of 6 min. Degassing rate using the optimum parameters reaches 68%. In addition, the comparison experiments among C2Cl6 refining, rotary impeller degassing, and combined treatment of C2Cl6 refining and rotary impeller degassing for 4004 Al alloy were performed. The experimental data indicated that the combined treatment of C2Cl6 refining and rotary impeller degassing has the best degassing effect. Degassing rate of C2Cl6 refining, rotary impeller degassing and combined refining treatment is 39%, 69.1% and 76.9%, respectively. The mechanical properties of the specimen refined by rotary impeller degassing were higher than those by C2Cl6 refining, but lower than those by combined refining treatment. | Wang Liping Cao Guojian Guo Erjun Wang Guojun Lü Xinyu | 2013 | China Foundry2013,10,2: | 2 |
| 9 | Gradual chlorination at different positions of D-π-A copolymers based on benzodithiophene and isoindigo for organic solar cells显示文摘Isoindigo(IID)has been widely used as strong acceptor unit(A)to construct narrow bandgap polymers in organic field effect transistors(OFETs)and organic solar cells(OSCs).Combing with IID,we chose benzodithiophene(BDT)as the donor unit(D)and thieno[3,2-b]thiophene(TT)as theπbridge to construct a new type of D-π-A polymer PE70.Based on PE70,we adopt the chlorination strategy to fine-tune photoelectric characteristics and film morphology,and then developed PE74 and PE75.By blending with non-fullerene acceptor(NFA)Y6,device based on PE74 with chloride substitution on the BDT unit showed increasing photovoltaic performance.In addition,further chlorine substitution on the IID(PE75)would greatly reduce the non-radiative voltage loss(ΔV3),and the distorted molecular conformation also took responsible for the excessive recombination.As results,PE74:Y6-based device achieves a power conversion efficiency(PCE)of 11.06%with open-circuit voltage(VOC)of 0.76 V,which are higher than those of PE70:Y6(PCE of 10.40%and VOC of 0.72 V)and PE75:Y6-based device(PCE of 6.24%and VOC of 0.84 V).This work demonstrates the regularity of the photovoltaic performance caused by chlorination strategy in polymer in the non-fullerene OSC devices,which provide important insights into highperformance photovoltaic materials. | Jialing Zhou Bao Zhang Yanfang Geng Qing Guo Qiang Guo Erjun Zhou | 2021 | Materials Reports(Energy)2021,1,4: | 1 |
| 10 | The first application of isoindigo-based polymers in non-fullerene organic solar cells显示文摘Although isoindigo(IID)-based polymers can realize high charge mobility,these materials are currently confined to fullerenebased organic solar cells(OSCs).Herein,we designed a pair of alternative D-π-A type copolymers,PE71 and PE72,to expand the application in non-fullerene OSCs,where benzo[1,2-b:4,5-b′]thiophene(BDT),thieno[3,2-b]thiophene(TT)and IID units were used as D,A andπ-bridge,respectively.The aim of optimizing the length of alkyl chains on TT bridge is to ensure polymer solubility,crystallinity as well as miscibility with acceptor molecules.We find that PE71 and PE72 exhibit similar optical and electronic properties,but PE71 with shorter hexyl chain tends to aggregate into fiber-like structure.In the end,Y6 is selected as the electron acceptor because of suitable energy levels and complementary absorption spectrum.Finally,PE71:Y6 device realizes a power conversion efficiency(PCE)of 12.03%,which is obviously higher than that of PE72:Y6 device(9.74%)and is also the highest value for IID-based photovoltaic polymers.The charge transport,molecular aggregation,film morphology and energy loss analysis were systematically investigated.The improved photovoltaic performance of PE71:Y6 mainly originates from the better interpenetrating network structure toward facilitating exciton seperation and free charge carrier transportation.Our results indicate that IID-based D-π-A polymers can also be utilized in non-fullerene OSCs and the alkyl chains on the thieno[3,2-b]thiopheneπ-bridge have a vital effect on the photovoltaic performance. | Bao Zhang Ning An Hongbo Wu Yanfang Geng Yanming Sun Zaifei Ma Weiwei Li Qiang Guo Erjun Zhou | 2020 | Science China Chemistry2020,63,9: | 1 |
| 11 | Integral Lift- ing and Seismic Isolation Retrofil of Great Hall of Nan- jing Museum显示文摘 | Tong Guo Erjun Wu Aiqun Li | 2012 | Journal of Performance of Construc- ted Facilities2012,,6: | 1 |
| 12 | Selective fluorination on donor and acceptor for management of efficiency and energy loss in non-fullerene organic photovoltaics显示文摘Although fluorination has been proved effective to modulate optoelectronic properties and film morphology,knowledge of managing power conversion efficiency(PCE)and energy loss(Eloss)of organic photovoltaics(OPVs)by selective fluorination on the donor and/or acceptor is lacking.Herein we designed and synthesized three 1,2,3-benzotriazole(BTA)-based linear polymers(PE45,PE46 and PE47)with different numbers of fluorine atom substitution on the conjugated phenyl side chain.Two classic non-fullerene acceptors(NFAs)Y5(without fluorination)and Y6(with fluorination)were utilized to manage the device efficiency and energy loss.The results revealed that increasing fluorine substitutions on polymer donor improved the OPV efficiencies when the fluorinated Y6 was used as the acceptor,whereas decreased the PCEs when the non-fluorinated Y5 was used as the acceptor.The energy loss declined with the growing fluorine substitutions on polymer donor,and Y5 systems gave the lower values in comparison with the corresponding Y6 cases.It turns out that PE47:Y6 achieved the highest PCE of 15.58%with an open-circuit voltage(VOC)of 0.84 V(Eloss=0.56 e V)due to the highest and balanced hole/electron mobilities,suppressed bimolecular recombination and fibril network morphology,which is the highest value in the BTA-based polymers.Furthermore,PE47:Y5 attained an ultralow non-radiative energy loss of 0.15 e V,which is one of the lowest values among the reported OPVs.Our work could not only give a direct path on how to manage the efficiency and energy loss by selective fluorination on donor and acceptor,but also show a deep understanding on charge generation,transport and collection induced by selective fluorination. | You Chen Peng Lei Yanfang Geng Ting Meng Xiangyu Li Qingdao Zeng Qing Guo Ailing Tang Yufei Zhong Erjun Zhou | 2023 | Science China Chemistry2023,66,4: | 0 |
| 13 | Side chain engineering of quinoxaline-based small molecular nonfullerene acceptors for high-performance poly(3-hexylthiophene)-based organic solar cells显示文摘Poly(3-hexylthiophene)(P3HT)is one of the most used semiconducting polymers for organic photovoltaics because it has potential for commercialization due to its easy synthesis and stability.Although the rapid development of the small molecular non-fullerene acceptors(NFAs)have largely improved the power conversion efficiency(PCE)of organic solar cells(OSCs)based on other complicated p-type polymers,the PCE of P3HT-based OSCs is still low.In addition,the design principle and structure-properties correlation for the NFAs matching well with P3HTare still unclear and need to be investigated in depth.Here we designed a series of NFAs comprised of acceptor(A)and donor(D)units with an A2-A1-D-A1-A2 configuration.These NFAs are abbreviated as Qx3,Qx3 b and Qx3c,where indaceno[1,2-b:5,6-b′]dithiophene(IDT),quinoxaline(Qx)and 2-(1,1-dicyanomethylene)rhodanine serve as the middle D,bridged A1 and the end group A2,respectively.By subtracting the phenyl side groups appended on both IDT and Qx skeletons,the absorption spectra,energy levels and crystallinity could be regularly modulated.When paired with P3 HT,three NFAs show totally different photovoltaic performance with PCEs of 3.37%(Qx3),6.37%(Qx3b)and 0.03%(Qx3 c),respectively.From Qx3 to Qx3b,the removing of phenyl side chain in the middle IDT unit results in the increase of crystallinity and electron mobility.However,after subtracting all the grafted phenyl side groups on both IDT and Qx units,the final molecule Qx3 c exhibits the lowest PCE of only 0.03%,which is mainly attributed to the serious phase-separation of the blend film.These results demonstrate that optimizing the substituted position of phenyl side groups for A2-A1-D-A1-A2 type NFAs is vital to regulate the optoelectronic property of molecule and morphological property of active layer for high performance P3HT-based OSCs. | Bo Xiao Qianqian Zhang Gongqiang Li Mengzhen Du Yanfang Geng Xiangnan Sun Ailing Tang Yingliang Liu Qiang Guo Erjun Zhou | 2020 | Science China Chemistry2020,63,2: | 0 |
| 14 | Efect of residual Al content on microstructure and mechanical properties of Grade B+Steel for castings for locomotives显示文摘The bogie made of Grade B+ steel is one of the most important parts of heavy haul trains. Some accidents were found to be the result of fracture failure of the bogies. It is very important to find the reason why the fracture failure occurred. Because Al was added for the final deoxidation during the smelting process of the Grade B+Steel, residual Al existed to some extent in the castings. High residual Al content in the bogie casting was presumed to be the reason for the fracture. In this work, the influence of residual Al content in the range of 0.015wt.% to 0.3wt.% on the microstructure and mechanical properties of the Grade B+ Steel was studied. The experimental results showed that when the residual Al content is between 0.02wt.% and 0.20wt.%, the mechanical properties of the steel meet the requirements of technical specification for heavy haul train parts, and the fracture is typical plastic fractures. If the residual Al content is less than 0.02wt.%, the microstructures are coarse, and the mechanical properties can not meet the demand of bogie steel castings. When the residual Al content is more than 0.2wt.%, the elongation, reduction of area, and low-temperature impact energy markedly deteriorate. The fracture mode then changes from plastic fracture to cleavage brittle fracture. Therefore, the amount of Al addition for the final deoxidation during the smelting process must be strictly controlled. The optimum addition amount needs to be controlled within the range of 0.02wt.% to 0.20wt.% for the Grade B+Steel. | Wang Kaifeng Guo Erjun Cao Guojian Wang Liping Feng Yicheng Jiang Wenyong Tao Chunguo | 2013 | China Foundry2013,10,6: | 0 |
| 15 | The development of A-DA’D-A type nonfullerene acceptors containing non-halogenated end groups显示文摘Compared with perovskite solar cells and silicon solar cells,the excessive voltage loss(Vloss)becomes a stubborn stone that seriously hinders the further improvement of organic photovoltaic(OPV).Thus,many researchers focus on finding an effective material system to achieve high-performance OPVs with low Vloss.In recent 5 years,acceptor-donor-acceptor’-donor-acceptor(A-DA’D-A)type non-fullerene acceptors(NFAs)have attracted great attention because of their promising photovoltaic performance.Among them,A-DA’D-A type NFAs containing non-halogenated end group(NHEG)exhibit the large potential to achieve high open-circuit voltage(VOC)for the state-of-the-art OPVs,because of high-lying molecular energy levels and decreasing Vloss.In this review,we systematically summarize the recent development of A-DA’D-A type NHEG-NFAs and the impact of different NHEGs on the optoelectronic properties as well as the photovoltaic performance.In addition,we especially analyze the Vloss of NHEG-NFAs in the binary and ternary OPV devices.At last,we provide perspectives on the further molecular design and future challenges for this kind of materials as well as suggested solutions. | Hongxing Liu Tingting Dai Jialing Zhou Helin Wang Qing Guo Qiang Guo Erjun Zhou | 2023 | Nano Research2023,16,12: | 0 |