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Acta Metallurgica Sinica(English Letters) 2018年第4期31卷 337-350页

作者： Jin-Long fu Hong-jun Jiang Kai-Kun Wang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Wuxi Turbine Blade Co. LtdWuxi 214174JiangsuChina

A modified strain-induced melt activation（SIMA）process consisting of homogenization,equal-channel angular pressing（ECAP）and subsequent heating to the semisolid temperatures was introduced to prepare the 7075 aluminum alloy with superior thixotropic *** effects of both the homogenization and the number of ECAP passes,as well as the isothermal temperatures on the microstructural evolution,were *** results indicate that ideal microstructure wherein fine and globular solid grains surrounded by uniform liquid films can be achieved through ECAP deformation-recrystallization *** the number of ECAP passes accelerates the recrystallization of strained grains,thus reducing the average grain size and improving the grain ***,higher holding temperatures and prolonged soaking time can improve the growth of the solid *** main coarsening mechanisms,*** and Ostwald ripening,contribute to the growth of the solid grains simultaneously and *** tensile strength of the 7075 alloys after four-pass ECAP-based SIMA and T6 heat treatment is relatively lower than the as-received billet,while the elongation of SIMA processed samples is much higher than that of as-received *** the number of ECAP passes improves the tensile strength for alloys with and without T6 treatment due to the fine grain strengthening mechanism.

关键词： Semisolid Aluminum Equal-channel angular pressing Mierostructural evolution Tensileproperty

Modification of Sn–1.0Ag–0.5Cu solder using nickel and boron

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Rare Metals 2015年第11期34卷 783-788页

作者： jun-Feng Qu jun Xu Qiang Hu fu-Wen Zhang Shao-Ming Zhang National Engineering Research Center for Nonferrous Metal Composites General Research Institute for Nonferrous Metals Technology Department Beijing COMPO Advanced Technology Co. Ltd.

Effects of Ni and B additions on the microstructure and growth behavior of the intermetallic compound(IMC) of Sn–1.0Ag–0.5Cu alloys(SAC105) were investigated in this study. Results show that microadditions of Ni and B result in volume fraction of primary Sn increasing and the grain size decreasing observably. It is found that a large number of fine reinforcement particles with network-like shape are found in the solder, and the thickness of interfacial IMC layer in the solder joint is grew less than that of SAC105 with longer aging time. Shear test results reveal that as-soldered solder joints of microalloyed SAC105 have better shear strength than that of SAC105 solder alloy.

关键词： Lead-free solder Sn–1.0Ag–0.5Cu Interfacial reacti

Cu_2ZnSnS_4 thin films prepared by sulfurization of ion beam sputtered precursor and their electrical and optical properties

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Rare Metals 2006年第Z1期25卷 315-319页

作者： ZHANG jun SHAO Lexi fu Yujun XIE Erqing School of Physics Science and Technology Zhanjiang Normal University Zhanjiang 524048 China School of Physics Science and Technology Lanzhou University Lanzhou 730000 China School of Physics Science and Technology Zhanjiang Normal University Zhanjiang 524048 China School of Physics Science and Technology Lanzhou University Lanzhou 730000 China School of Physics Science and Technology Lanzhou University Lanzhou 730000 China

Cu2ZnSnS4 (CZTS) thin films were successfully prepared by sulfurization of ion bean sputtered precursors on soda-lime glass substrate. The single phase of stannite-type structure CZTS films were obtained as revealed in EDS and XRD analysis when the ratios of the constituents of CZTS thin films are close to stoichiometric by optimizing the conditions of precursor preparation and sulfurization. A low sheet resistivity as about 0.156 Ω·cm and a high absorption coefficient as 1×104 cm-1 were achieved in this method by Hall effect measurements and UV-VIS spectrophotometer. The optical band-gap energy of the CZTS sample is about 1.51 eV, which is very close to the optimum value for a solar-cell absorber.

关键词： Cu2ZnSnS4 thin film solar-cell ion beam sputtering

Three dimensional nonlinear shock waves in inhomogeneous plasmas with different size dust grains and external magnetized field

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Plasma Science and Technology 2020年第3期22卷 1-7页

作者： Liping ZHANG jun fu junyan SU School of Sciences Lanzhou University of TechnologyLanzhou 730050People’s Republic of China

The evolution of three dimensional nonlinear shock waves is investigated in a dusty plasma with inhomogeneous particles’density,nonadiabatic dust charge variation,external magnetized field and power law dust size *** this purpose,a modified nonlinear Korteweg-de Vries Burgers equation containing variable coefficients is obtained by reductive perturbation *** effects of inhomogeneity,dust size distribution,external magnetized field,dust charge variation and obliqueness parameter on shock structures are numerically examined in great ***,research results show that oscillatory shock waves and monotone shock waves exist and transform each other in this system.

关键词： shock structures inhomogeneity nonadiabatic dust charge fluctuation dust size distribution

Morphology and distribution of precipitates and their effects on compression cracks in Fe-6.5Si-0.02B electrical steel

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Journal of Iron and Steel Research International 2018年第1期25卷 99-107页

作者： Zhi-hao Zhang jun-li Wang Hua-dong fu Institute for Advanced Materials and Technology Universityof Science and Technology Beijing Beijing 100083 China Beijing Amorphous Energy Conservation Materials IndustryAlliance Beijing 100081 China

Morphology and distribution of precipitates in the Fe-6.5Si-0.02B alloy were characterized, and these effects on room- temperature compression cracks were investigated. The results showed that the precipitate in the Fe-6.5Si-0.02B alloy is FezB with body-centered tetragonal structure, and its nano-hardness is 15.0 GPa which is higher than that of the matrix （- 8.5 GPa）. In the as-cast alloys, most of the intragranular precipitates are coarse lath-like with the length of 5-15 μm and width of 2-5 μm, and the precipitates formed at the grain boundaries are of about 2-3 μm in width. After oil quenching followed by heat treatment at 1100 ℃ for more than 30 min, the precipitates inside grains are refined with a size of several hundred nanometers and the precipitates at the grain boundaries are refined with a size of 〈 1 μm. After compression test, transgranular and intergranular cracks occur in the as-cast alloys with coarse precipitates. For the quenched alloys with fine precipitates, the number of cracks decreases significantly, and no transgranular cracks happen because some cracks are blocked or the propagation direction is changed by grain boundary.

关键词： Fe-6.5 wt% Si alloy Precipitates Nano-hardness Room-temperature compression

Effects of initial grain size and strain on grain boundary engineering of high-nitrogen CrMn austenitic stainless steel

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International Journal of Minerals,Metallurgy and Materials 2018年第8期25卷 922-929页

作者： Zhen-hua Wang Jian-jun Qi Wan-tang fu School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China HBIS Group Technology Research Institute Shijiazhuang 050023China

18 Mn18 Cr0.5 N steel with an initial grain size of 28–177 μm was processed by 2.5%–20% cold rolling and annealing at 1000°C for 24 h,and the grain boundary character distribution was examined via electron backscatter *** strain(2.5%) favored the formation of low-Σ *** this strain,the fraction of low-Σ boundaries was insensitive to the initial grain ***,specimens with fine initial grains showed decreasing grain size after grain boundary engineering *** fraction of low-Σ boundaries and the(Σ9 + Σ27)/Σ3 value decreased with increasing strain; furthermore,the specimens with fine initial grain size were sensitive to the ***,the effects of the initial grain size and strain on the grain boundary engineering were discussed in detail.

关键词： grain boundary engineering grain boundary character distribution grain size strain austenitic stainless steel

Effects of thiocyanate anions on switching and structure of poly(N-isopropylacrylamide) brushes

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Chinese Physics B 2019年第6期28卷 262-269页

作者： Xin-jun Zhao Zhi-fu Gao Xinjiang Laboratory of Phase Transitions and Microstructures of Condensed Matter Physics Yili Normal UniversityYining 835000China Laboratory of Micro-Nano Electro Biosensors and Bionic Devices Yili Normal UniversityYining 835000China Xinjiang Astronomical Observatory Chinese Academy of Sciences150Science 1-StreetUrumqi 830011China

In this work, we investigate the effects of thiocyanate anions on the switching and the structure of poly(Nisopropylacrylamide)(PNIPAM) brushes using a molecular theory. Our model takes into consideration the PNIPAM–anion bonds, the electrostatic effects and their explicit coupling to the PNIPAM conformations. It is found that at low thiocyanate anion concentration, as the anion concentration of thiocyanate increases, thiocyanate anions are more associated with PNIPAM chains through the PNIPAM–anion bonds, which contributes to stronger electrostatic repulsion and leads to an increase of lower critical solution temperature(LCST). By analyzing the average volume fractions of PNIPAM brushes,it is found that the PNIPAM brush presents a plateau structure. Our results show that the thiocyanate anions promote phase segregation due to the PNIPAM–anion bonds and the electrostatic effect. According to our model, the reduction of LCST can be explained as follows: at high thiocyanate anion concentration, with the increase of thiocyanate concentration, more ion bindings occurring between thiocyanate anions and PNIPAM chains will result in the increase of the hydrophobicity of PNIPAM chains;when the increase of electrostatic repulsion is insufficient to overcome the hydrophobic interaction of PNIPAM chains, it will lead to the reduction of brush height and LCST at high thiocyanate anion concentration. Our theoretical results are consistent with the experimental observations, and provide a fundamental understanding of the effects of thiocyanate on the LCST of PNIPAM brushes.

关键词： molecular theory PNIPAM brushes effect of thiocyanate anions

Fault Early Diagnosis of Rolling Element Bearings Combining Wavelet Filtering and Degree of Cyclostationarity Analysis

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Journal of Shanghai Jiaotong university(Science) 2005年第4期10卷 446-448,455页

作者： zhou fu-chang（周福昌） CHEN Jin（陈进） HE jun（何俊） BI Guo （毕果） LI fu-cai （李富才） ZHANG Gui-cai （张桂材） State Key Lab. of Vibration Shock and Noise Shanghai Jiaotong Univ. Shanghai 200240 China

The vibration signals of rolling element bearing are produced by a combination of periodic and random processes due to the machine’s rotation cycle and interaction with the real world. The combination of such components can give rise to signals, which have periodically time-varying ensemble statistical and are best considered as cyclostationary. When the early fault occurs, the background noise is very heavy, it is difficult to disclose the latent periodic components successfully using cyclostationary analysis alone. In this paper the degree of cyclostationarity is combined with wavelet filtering for detection of rolling element bearing early faults. Using the proposed entropy minimization rule. The parameters of the wavelet filter are optimized. This method is shown to be effective in detecting rolling element bearing early fault when cyclostationary analysis by itself fails.

关键词： cyclostationary degree of cyclostationarity fault diagnosis rolling element bearings

Water quality forecast through application of BP neural network at Yuqiao reservoir

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1482-1487页

作者： ZHAO Ying NAN jun CUI fu-yi GUO Liang School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

This paper deals with the study of a water quality forecast model through application of BP neural network technique and GUI (Graphical User Interfaces) function of MATLAB at Yuqiao reservoir in Tianjin. To overcome the shortcomings of traditional BP algorithm as being slow to converge and easy to reach extreme minimum value,the model adopts LM (Leven-berg-Marquardt) algorithm to achieve a higher speed and a lower error rate. When factors affecting the study object are identified,the reservoir's 2005 measured values are used as sample data to test the model. The number of neurons and the type of transfer functions in the hidden layer of the neural network are changed from time to time to achieve the best forecast results. Through simulation testing the model shows high efficiency in forecasting the water quality of the reservoir.

关键词： Water quality forecast BP neural network MATLAB Graphical User Interfaces (GUI)

Implantable versatile oxidized bacterial cellulose membrane for postoperative HNSCC treatment via photothermal-boosted immunotherapy

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Nano Research 2023年第1期16卷 951-963页

作者： jun-Jie zhou Xiao-Hong Li Peng-Yu He fu-Yu Qi Muhammad Wajid Ullah Shu-Jin Li Yuan-Tong Liu Lin-Lin Bu Guang Yang Zhi-jun Sun The State Key Laboratory Breeding Base of Basic Science of Stomatology(Hubei-MOST)&Key Laboratory of Oral Biomedicine Ministry of Education School&Hospital of StomatologyWuhan UniversityWuhan 430079China Department of Oral Maxillofacial Head Neck Oncology School&Hospital of StomatologyWuhan UniversityWuhan 430079China Key Laboratory of Artificial Micro-and Nano-Structures of Ministry of Education School of Physics and Technology Wuhan UniversityWuhan 430079China Department of Biomedical Engineering College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China Biofuels Institute School of the Environment and Safety EngineeringJiangsu UniversityZhenjiang 212013China

The recurrence of head and neck squamous cell carcinoma(HNSCC)after surgical resection continues to pose a major challenge to cancer *** HNSCC exhibits a low response rate to immune checkpoint blockade(ICB),while photothermal therapy(PTT)can increase the infiltration of immune cells to make tumors more susceptible to cancer *** this regard,we designed and constructed a novel multifunctional nanocomposite comprised of oxidized bacterial cellulose(OBC),thrombin(TB),and gold nanocages(AuNCs)containing anti-programmed death 1(PD-1)antibody(αPD-1@AuNCs),which allows the combination of therapies with remarkable postoperative antitumor immunity to control local tumor ***αPD-1@AuNCs displayed high light-to-heat conversion efficiency and induced pyroptosis under near infrared(NIR)irradiation,which activated a potent antitumor immune *** importantly,the therapeutic system could induce tumor pyroptosis and enhance antitumor immune response by increasing T-cell infiltration and reducing the immune suppressive cells,when combined with local ICB therapy,which effectively avoided the tumor recurrence in a HNSCC postoperative mice ***,the newly developed multifunctional nanocomposites could be a promising candidate for the treatment of postoperative HNSCC.

关键词： head and neck squamous cell carcinoma(HNSCC) oxidized bacterial cellulose pyroptosis immunotherapy postoperative treatment