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journal of Materials Science & Technology 2019年第11期35卷 2682-2692页

作者： Xiaochen Zhou Fan Yang Xiaoyan Gong Ming zhao Yufeng Zheng Zhili Sun Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing100871China Beij.ng Percutek Therapeutics Co. LtdBeijing102600China Suzhou Innomed Medical Device Co. LtdSuzhou215123China 1707 Ralston Branch Way Sugar LandTX77479USA State Key Laboratory for Turbulence and Complex System College of EngineeringPeking UniversityBeijing100871China

Endovascular repair of the thoracic aorta with self-expanding stent-grafts has been emerging as a less invasive alternative treatment compared with conventional open *** the promising efficacy and safety of endovascular stent grafting,the stent-graft failure remains a major concern in terms of stent migration,device fatigue,and the risk of *** associated with the stent-grafts involve optimized geometrical structure,lifetime fatigue resistance,and adequate radial *** this work,a novel endovascular stent-graft system is developed specially for the treatment of Stanford type B thoracic aortic dissections(TAD).numerical study with finite element analysis(FEA)was utilized to evaluate the mechanical behaviors of the individual stent *** of the simulation were validated by experimental *** on the systematic analysis of the parametric variations,a final stent-graft system was developed by the selection and arrangement of the individual stent components,targeting an optimal performance for treatment of *** optimized solution of the stent-graft system was tested in clinical trials,showing advantageous therapeutic efficacy.

关键词： Stent-graft Thoracic aortic dissection Seal zone Fatigue safety factor Radial force Finite element analysis nitinol

Progress in mechanochromic luminescence of gold(Ⅰ) complexes

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Chinese Chemical Letters 2021年第12期32卷 3718-3732页

作者： Shiqi Cheng zhao Chen Ya Yin Yue Sun Shenghua Liu Hubei Key Laboratory of Catalysis and Materials Science College of Chemistry and Material SciencesSouth-Central University for NationalitiesWuhan 430074China jiangxi Key Laboratory of Organic Chemistry Jiangxi Science and Technology Normal UniversityNanchang 330013China Key Laboratory of Pesticide and Chemical Biology Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhan 430079China

Photophysical properties of organic and organometallic luminophors are closely related with their molecular packings, enabling the exploitation of stimuli-responsive functional luminescent *** molecules, which can change their luminescence characteristics after mechanical stimulus, have received an increasing interest due to their promising applications in multifunctional sensors and molecular switches. During the past two decades, the development of gold(Ⅰ) chemistry has been attracting the attention of plenty of researchers. Indeed, a variety of gold(I) complexes with fascinating photophysical behaviors have been discovered. This review focuses on the research progress in the different types of mechanoluminochromic gold(Ⅰ) complexes, including mono-, bi-and multi-nuclear gold(Ⅰ)systems. Their interesting luminescence behaviors of these gold(Ⅰ)-containing luminogens upon mechanical stimulus and the proposed mechanisms of their observed mechanochromic luminescence are summarized systematacially. Moreover, this review will put forward an outlook about the possible opportunities and challenges in this significative scientific field.

关键词： Gold(Ⅰ)complexes Mechanochromic luminescence Mechanisms Molecular packings Aurophilic interactions

Steady-State Cornering Properties of a non-pneumatic Tire with Mechanical Elastic Structure

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Transactions of nanj.ng University of Aeronautics and Astronautics 2017年第5期34卷 586-592页

作者： Fu Hongxun zhao Youqun Lin Fen Du Xianbin Zhu Mingmin College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

Mechanical elastic wheel(ME-wheel)is a new type of non-inflatable safety tyre,and the structure is significantly different from traditional pneumatic *** order to investigate cornering properties of ME-wheel,experimental research on mechanics characteristics of ME-wheel under steady-state cornering conditions are carried *** test of steady-state cornering properties of ME-wheel at different experimental parameter conditions is conducted by test bench for dynamic mechanical properties of *** property curves are used to analyze the steady-state cornering properties of ME-wheel,namely the variation tendency of lateral force or aligning torque with the increase of side-slip ***,evaluation indexes for cornering properties of ME-wheel are extracted and the effect of different experimental parameters(including vertical load,friction coefficient,and speed)on cornering properties of ME-wheel is contrastively *** proposed research can provide certain reference to facilitate structure parameters and cornering properties optimizing process of ME-wheel.

关键词： tyres non-pneumatic tyre mechanical elastic structure steady-state cornering properties

Synergistic enhancement on mechanical properties and corrosion resistance of biodegradable Mg-Zn-Y alloy via V-microalloying

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journal of Magnesium and Alloys 2024年第2期12卷 530-545页

作者： jiaxin Zhang Xin Ding Ruirun Chen Wenchao Cao j.nshan Zhang Rui zhao national Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyNo.92West Dazhi StreetHarbinHeilongjiang 150001China College of Materials Science and Engineering Taiyuan University of TechnologyNo.79West Yingze StreetTaiyuanShanxi 030024China

For the sake of improving the mechanical properties and corrosion resistance of biodegradable Mg alloy synergistically,various content of element V(0,0.05,0.10,0.15,0.20 wt.%)are introduced into an Mg-Zn-Y alloy with long-period stacking ordered(LPSO)structure,and the effects of V on its microstructure,mechanical properties and corrosion resistance are investigated *** results indicate that the grains are effectively refined by V addition,and the primaryα-Mg in Mg-Zn-Y-V0.1 alloy is most significantly refined,with grain size being decreased by 62%.The amount of 18R LPSO structure is increased owing to the V *** growth mode of the second phase(W-phase and 18R LPSO structure)is transformed to divorced growth pattern,which ascribes to the thermodynamic drive force of V to promote the nucleation of LPSO ***,18R LPSO structure presents a continuous *** to grains refinement and modification of second phase,the tensile strength and strain of alloys are both enhanced ***,the ultimate tensile strength and the elongation of V0.1 alloy are 254 MPa and 15.26%,which are 41%and 61%higher than those of V-free alloy,*** to the continuously distributed 18R LPSO structure with refined grains and stable product film,the weight loss and hydrogen evolution corrosion rates of V0.1 alloy are 7.1 and 6.2 mmy^(-1),respectively,which are 42.6%and 45.4%lower than those of V-free alloy.

关键词： Corrosion Mechanical property V-microalloying LPSO SKPFM

PTB7-Th based organic solar cell with a high V_(oc) of 1.05 V by modulating the LUMO energy level of benzotriazole-containing non-fullerene acceptor

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Science Bulletin 2017年第18期62卷 1275-1282页

作者： Bo Xiao Yingjie zhao Ailing Tang Haiqiao Wang j.ng Yang Erj.n Zhou CAS Key Laboratory of nanosystem and Hierarchical Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Organic-Inorganic Composite Beijing University of Chemical Technology Beijing 100029 China

The open-circuit voltage （Voc） of classical photovoltaic polymers, such as P3HT and PTB7-Th, are always restricted when combining with fullerene derivatives, due to the difficulty of modulating the energy levels of fullerene derivatives. Thus, design of new non-fullerene small molecule acceptor （nFSMA） is very significant to match with these mature polymer donors and improve the Voc and power conversion efficiency （PCE）. Here, a new benzotriazole （BTA）-based nFSMA, BTA7 was synthesized by adopting A2----A1--D--A1--A2 type molecular backbone. By using a strong electron-accepting unit of malononitrile （M） as terminal segment A2, BTA7 demonstrates strong crystallinity, red-shifted absorption spectrum and down-shifted lowest unoccupied molecular orbital （LUMO） energy levels in comparison with BTA1 and BTA2. Organic solar cells （OSCs） based on PTB7-Th：BTA7 realized a high Voc of 1.05 V with a moderate PCE of 4.60%. The energy loss （Eloss = Eg - eVoc） of 0.53 eV is lower than the experiential minimum value of 0.6 eV, which indicates PTB7-Th still has large potential to improve the Voc and photovoltaic performance after the development of novel electron acceptors.

关键词： Benzotriazole (BTA) Malononitrile Fullerene-free solar cells non-fullerene acceptor PTB7-Th

Recent research and development on forming for large magnesium alloy components with high mechanical properties

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journal of Magnesium and Alloys 2023年第11期11卷 4054-4081页

作者： Zhimin Zhang jianmin Yu Yong Xue Beibei Dong Xi zhao Qiang Wang College of Materials Science and Engineering North University of China3 Xueyuan RoadTaiyuan 030051China

The lightweight of high-end equipment relies on high mechanical properties magnesium(Mg) alloy structural components, because it is the best way to improve equipment service performance and reduce energy consumption. This article summarizes the current progress and characteristics of large-scale high-performance Mg alloy components by analyzing the strengthening-toughening mechanisms, characteristics of plastic forming, and the preparation of large high mechanical properties forging blanks. Due to the lack of breakthroughs in the key technologies for forming large-scale Mg alloy components, their uniformity of mechanical properties and consistency are poor, the forming accuracy of components is low, and the production cost is high, which limit their engineering application and restrict the lightweight level of high-end equipment. In view of the above problems, the forming trends and research directions of large-scale and high mechanical properties Mg alloy components are proposed in this paper. It can provide help for the breakthrough of the key technology of large-scale Mg alloy components with high mechanical properties and expand the application of Mg alloy in high-end products.

关键词： Mg alloys Wrought Mg alloys components Plastic forming Large-scale Mg alloys components High mechanical properties

Catalytic ozonation of thymol in reverse osmosis concentrate with core/shell Fe_3O_4@SiO_2@Yb_2O_3 catalyst:Parameter optimization and degradation pathway

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Chinese journal of Chemical Engineering 2017年第5期25卷 665-670页

作者： Liang Wang Anqi Liu zhaohui Zhang Bin zhao Yingming Xia Yun Tan State Key Laboratory of Separation Membranes and Membrane Processes Tianjin Polytechnic University Department of Environmental Engineering Tianjin Polytechnic University

In this work, a novel catalyst of Fe_3O_4@SiO_2@Yb_2O_3 was prepared and the degradation of thymol in reverse osmosis concentrate using ozonation was explored. The operational parameters, such as ozone dosage(8–48 mg·min^(-1)),initial thymol concentration(20–100 mg·L^(-1)), initial pH value(3–11), and catalyst Fe_3O_4@SiO_2@Yb_2O_3dosage(0.2–1.0 g), were studied focusing on the thymol degradation and COD removal. The results indicated that the increase in ozone dosage, initial p H value, and Fe_3O_4@SiO_2@Yb_2O_3dosage accelerated the thymol degradation and COD removal, while the increase in initial thymol concentration hampered the effect of ozonation. A pathway of thymol degradation by catalytic ozonation was proposed based on the intermediates detected by gas chromatography-mass spectrometer and ion chromatography. This paper can provide basic data and technical alternative for pollutant removal from reverse osmosis concentrate by ozonation.

关键词： Catalysis Ozonation Wastewater Thymol Degradation pathway

A salient edges detection algorithm of multi-sensor images and its rapid calculation based on PFCM kernel clustering

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Chinese journal of Aeronautics 2014年第1期27卷 102-109页

作者： Xu Guili zhao Yan Guo Ruipeng Wang Biao Tian Yupeng Li Kaiyu College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Multi-sensor image matching based on salient edges has broad prospect in applications, but it is difficult to extract salient edges of real multi-sensor images with noises fast and accurately by using common algorithms. According to the analysis of the features of salient edges, a novel salient edges detection algorithm and its rapid calculation are proposed based on possibility fuzzy C-means （PFCM） kernel clustering using two-dimensional vectors composed of the values of gray and texture. PFCM clustering can overcome the shortcomings that fuzzy C-means （FCM） cluster- ing is sensitive to noises and possibility C-means （PCM） clustering tends to find identical clusters. On this basis, a method is proposed to improve real-time performance by compressing data sets based on the idea of data reduction in the field of mathematical analysis. In addition, the idea that kernel-space is linearly separable is used to enhance robustness further. Experimental results show that this method extracts salient edges for real multi-sensor images with noises more accurately than the algorithm based on force fields and the FCM algorithm; and the proposed method is on average about 56 times faster than the PFCM algorithm in real time and has better robustness.

关键词： DaM reduction Edge detection Fuzzy clustering Possibility fuzzy C2means(PFCM)

nitrogen removal from coal gasification wastewater by activated carbon technologies combined with short-cut nitrogen removal process

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journal of Environmental Sciences 2014年第11期26卷 2231-2239页

作者： Qian zhao Hongj.n Han Baolin Hou Haifeng Zhuang Shengyong jia Fang Fang State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology

A system combining granular activated carbon and powdered activated carbon technologies along with shortcut biological nitrogen removal （GAC-PACT-SBnR） was developed to enhance total nitrogen （Tn） removal for anaerobically treated coal gasification wastewater with less need for external carbon resources. The Tn removal efficiency in SBnR was significantly improved by introducing the effluent from the GAC process into SBnR during the anoxic stage, with removal percentage increasing from 43.8%49.6% to 68.8%-75.8%. However, the Tn removal rate decreased with the progressive deterioration of GAC adsorption. After adding activated sludge to the GAG compartment, the granular carbon had a longer service-life and the demand for external carbon resources became lower. Eventually, the Tn removal rate in SBnR was almost constant at approx. 43.3%, as compared to approx. 20.0% before seeding with sludge. In addition, the production of some alkalinity during the denitrification resulted in a net savings in alkalinity requirements for the nitrification reaction and refractory chemical oxygen demand （COD） degradation by autotrophic bacteria in SBnR under oxic conditions. PACT showed excellent resilience to increasing organic loadings. The microbial community analysis revealed that the PACT had a greater variety of bacterial taxons and the dominant species associated with the three compartments were in good agreement with the removal of typical pollutants. The study demonstrated that pre-adsorption by the GAC-sludge process could be a technically and economically feasible method to enhance Tn removal in coal gasification wastewater （CGW）.

关键词： Coal gasification wastewater Short-cut nitrogen removal Granular activated carbon PCR-DGGE Denitrification enhancement

Plasma enhanced chemical vapor deposition of excellent a-Si：H passivation layers for a-Si：H/c-Si heteroj.nction solar cells at high pressure and high power

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Frontiers in Energy 2017年第1期11卷 85-91页

作者： Lei zhao Wenbin ZHAnG j.ngwei CHEn Hongwei DIAO Qi WAnG Wenj.ng WAnG Key Laboratory of Solar Thermal Energy and Photovoltaic System of Chinese Academy of Sciences Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China GCL System Integration Technology Co. Ltd Shanghai 201406 China

The intrinsic a-Si：H passivation layer inserted between the doped a-Si：H layer and the c-Si substrate is very crucial for improving the performance of the a-Si：H/c- Si heteroj.nction （SHj） solar cell. The passivation performance of the a-Si：H layer is strongly dependent on its microstructure. Usually, the compact a-Si：H deposited near the transition from the amorphous phase to the nanocrystalline phase by plasma enhanced chemical vapor deposition （PECVD） can provide excellent passivation. However, at the low deposition pressure and low deposition power, such an a-Si：H layer can be only prepared in a narrow region. The deposition condition must be controlled very carefully. In this paper, intrinsic a- Si：H layers were prepared on n-type Cz c-Si substrates by 27.12 MHz PECVD at a high deposition pressure and high deposition power. The corresponding passivation perfor- mance on c-Si was investigated by minority carrier lifetime measurement. It was found that an excellent a-Si：H passivation layer could be obtained in a very wide deposition pressure and power region. Such wide process window would be very beneficial for improving the uniformity and the yield for the solar cell fabrication. The a-Si：H layer microstructure was further investigated by Raman and Fourier transform infrared （FTIR） spectro-scopy characterization. The correlation between the microstructure and the passivation performance was revealed. According to the above findings, the a-Si：H passivation performance was optimized more elaborately. Finally, a large-area SHj solar cell with an efficiency of 22.25% was fabricated on the commercial 156 mm pseudo-square n-type Cz c-Si substrate with the opencircuit voltage （Voc） of up to 0.732 V.

关键词： PECVD high pressure and high power,a-Si:H microstructure passivation heteroj.nction solar cell