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Defence Technology（防务技术） 2022年第10期18卷 1886-1894页

作者： Shuai-da Zhu Zi-chen Hu yu-qi cao xiao-xia Li yu-qi feng Xiong cao Peng Deng Shanxi Fire&Explosion-Proofing Safety Engineering and Technology Research Center North University of ChinaTaiyuan030051PR China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China

Improving the thermal decomposition performance of hexanitrohexaazaisowurtzitane(CL-20)by appropriate methods is helpful to promote the combustion performance of CL-20-based solid *** this study,we synthesized a sandwich structure of CL-20 and nanoporous carbon scaffolds film(NCS)and emphatically studied the thermal decomposition performance of the composite *** analysis and differential scanning calorimetry were used to measure the thermal decomposition process of the composite *** kinetic parameters of thermal decomposition were calculated by the thermal dynamic analysis software *** results showed that the thermal decomposition performance of the sandwich structure of CL-20 and NCS was better than *** the tested samples,NCS with a pore size of 15 nm had the best catalytic activity for the thermal decomposition of ***,the thermal decomposition curve of the composite structure at the heating rate of 1 K/min was deconvoluted by mathematical method to study the thermal decomposition *** a possible catalytic mechanism was *** excellent thermal decomposition performance is due to the sandwich structure enhances the interface reaction of CL-20 and *** work may promote the extensive use of CL-20 in the field of solid rocket propellant.

关键词： CL-20 NCS Catalysis Thermal decomposition Sandwich structure

Novel Method Fusing （2D）^2 LDA with Multichannel Model for Face Recognition

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Journal of Harbin Institute of Technology(New Series) 2015年第6期22卷 110-114页

作者： xia liu Yang cao yu cao Bo Wang School of Automation Harbin University of Science and Technology

A fusion method of Gabor features and (2D)~2LDA for face feature extraction is proposed in this paper. Gabor filters are utilized to extract multi-direction and multi-scale features from facial image to employ its robust performance for illumination,expressional variability and other factors. The extracted features have the defect of high dimension and redundancy data.(2D)~2LDA is implemented to reduce the dimension of Gabor features and select effective feature data. Finally, the nearest neighbor classifier is used to classify characteristics and complete face recognition. The experiments are implemented by using ORL database and Yale database respectively. The experimental results show that the proposed method significantly reduces the dimension of Gabor features and decrease the influence of other factors. The proposed method acquires excellent recognition accuracy and has light architectures as well.

关键词： face recognition feature extraction Gabor filer (2D)^2LDA

Exploring influence of MgO/cao on crystallization characteristics to understand fluidity of synthetic coal slags

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Chinese Journal of Chemical Engineering 2023年第1期53卷 1-13页

作者： meng Li Jianliang Xu Huixia xiao xia liu Guangsuo yu xueli Chen Institute of Clean Coal Technology East China University of Science and TechnologyShanghai 200237China State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China

The crystallization has significant influence on fluidity of slag and slag discharge of entrained-flow-bed(EFB) gasifier. The crystallization characteristics and fluidity of five synthetic slags with different MgO/cao ratios prepared on the basis of the range of oxide contents of Zhundong coal ash were investigated in this study. The results show that with the MgO/cao ratio increase, the initial crystallization temperature increases, and the main temperature range of crystallization ratio growth moves to higher temperature range gradually which causes Tp25(Tp25is the temperature corresponding to the viscosity of 25 Pa·s)to increase. Mg-rich crystals are formed preferentially than Ca-rich crystals when adding the same amount of MgO and cao during cooling. The effective slagging operating temperature range decrease from 217 ℃ for the slag with a 0:4 MgO/cao ratio to 44 ℃ for the slag with a 4:0 MgO/cao ratio with the MgO/cao ratio increase. The slags with 2:2 and 1:3 MgO/cao ratios show similar effective slagging operating temperature range, Tp25and the temperature corresponding to the viscosity of 2 Pa·***, compared with the slag with a 1:3 MgO/cao ratio, the crystallization ratio and rate of slag with a 2:2 MgO/cao ratio are lower within lower temperature range(1300–1200 ℃), causing its lower critical viscosity temperature and wider actual operating temperature range. Of the five slags, the widest effective slagging operating temperature range and the lowest Tp25of the slag with a 0:4 MgO/cao ratio due to its low crystallization ratio, and wider actual operating temperature range of the slag with a 2:2 MgO/cao ratio make the two slags suitable for slag discharge of EFB gasifier.

关键词： Crystallization characteristics Fluidity Slags MgO/cao

Ni-Catalyzed Chelation-Assisted Direct Functionalization of Inert C—H Bonds

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Chinese Journal of Chemistry 2020年第6期38卷 635-662页

作者： Yan-Hua liu yu-Nong xia Bing-feng Shi Department of Chemistry Zhejiang UniversityHangzhouZhejiang 310027China

During the last two decades,impressive advancements have been achieved in transition metal-catalyzed chelation-assisted C—H functionalization *** reactions in this field are still dominated by precious 4d or 5d metals(e.g.,Pd,Rh,Ir),the 3d base metals(e.g.,Ni,Co,Cu,Fe)have made significant headway partially due to their relatively large abundance,low cost,low toxicity as well as their occasionally occurred novel reactivity when compared to their noble *** review will give a comprehensive summary on Ni-catalyzed functionalization of inert C—H bonds assisted by chelation *** clarity,the content is classified by the newly formed chemical bonds,namely C—C,C—N,C—chalcogen and C—halogen bond formation.

关键词： reaction. metals Functional

Research of influence of the additional electrode on Hall thruster plume by particle-in-cell simulation

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Chinese Physics B 2020年第9期29卷 377-383页

作者： Xi-feng cao Hui liu Da-Ren yu Laboratory of Plasma Propulsion Harbin Institute of TechnologyHarbin 150001China

Hall thruster is an electric propulsion device for attitude control and position maintenance of *** discharge process of Hall thruster will produce divergent *** plume will cause erosion,static electricity,and other interference to the main components,such as solar sailboard,satellite body,and ***,reducing the divergence of the plume is an important content in the research of thruster *** additional electrode to the plume area is a way to reduce the divergence angle of the plume,but there are few related *** paper uses the particle-in-cell(PIC)simulation method to simulate the effect of the additional electrode on the discharge of the Hall thruster,and further explains the effect mechanism of the additional electrode on parameters such as the electric field and plume divergence *** simulation results show that the existence of the additional electrode can enhance the potential near the additional *** increase of the potential can effectively suppress the radial diffusion of ions,and effectively reduce the plume divergence *** simulation results show that when the additional electrode is 30 V,the half plume divergence angle can be reduced by 18.21%.However,the existence of additional electric electrode can also enhance the ion bombardment on the magnetic *** additional electrode is relatively outside,the plume divergence angle is relatively small,and it can avoid excessive ion bombardment on the magnetic *** research work of this paper can provide a reference for the beam design of Hall thruster.

关键词： Hall thruster additional electrode plume divergence

Synthesis,pharmacokinetics and in vivo antifungal activity of the novel water-soluble prodrugs of itraconazole analogue YL-24

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Chinese Chemical Letters 2013年第4期24卷 321-324页

作者： yu liu Xu-feng cao Xin liu Yong-Bing cao Wen-jing Chu yu-She Yang State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of Sciences School of Pharmacy Second Military Medical University State Key Laboratory of Drug Research Shanghai Institute of Materia MedicoChinese Academy of Sciences

To improve the aqueous solubility of an itraconazole analogue, compound 1 （YL-24）, a series of novel prodrugs were synthesized. Among these prodrugs, the phosphate disodium salt compound 7 exhibited excellent aqueous solubility （9.8 mg/mL） at near-neutral pH and sufficient stability in buffer solutions, along with favorable pharmacokinetic profiles. In particular, compounds 1 and 7 provided moderate survival efficacy in murine systemic Candida albicans SC5314 infection model, but their efficacy was weaker than that of fluconazole.

关键词： SynthesisAntifungalWater-soluble prodrugsltraconazole analogue

Ammonium-dependent regulation of ammonium transporter ZmAMT1s expression conferred by glutamine levels in roots of maize

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Journal of Integrative Agriculture 2022年第8期21卷 2413-2421页

作者： HUI jing liu Zhi DUAN feng-ying ZHAO Yang LI xue-lian AN xia WU xiang-yu yuAN Li-xing College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193P.R.China

In maize,two root epidermis-expressed ammonium transporters ZmAMT1;1a and ZmAMT1;3 play major roles in highaffinity ammonium ***,the transcriptional regulation of ZmAMT1s in roots for ensuring optimal ammonium acquisition remains largely ***,using a split root system we showed that ZmAMT1;1a and ZmAMT1;3transcript levels were induced by localized ammonium supply to nitrogen-deficient *** enhanced expression of Zm AMT1s correlated with increases in ^(15)NH_(4)^(+)influx rates and tissue glutamine concentrations in *** ammonium was supplied together with methionine sulfoximine,an inhibitor of glutamine synthase,ammonium-induced expression of ZmAMT1s disappeared,suggesting that glutamine rather than ammonium itself regulated ZmAMT1s *** glutamine was supplied to nitrogen-deficient roots,expression levels of ZmAMT1s were enhanced,and negative feedback regulation could subsequently occur by supply of glutamine at a high ***,our results indicated an ammonium-dependent regulation of ZmAMT1s at transcript levels,and a dual role of glutamine was suggested in the regulation of ammonium uptake in maize roots.

关键词： ammonium transporter pH glutamine maize roots nitrogen transcriptional regulation

Quantitative and morphological differences of nerve fibers between proliferative and mature scars in two-and three-dimensional spaces

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Neural Regeneration Research 2010年第2期5卷 132-137页

作者： Yibing Wang xia Li Rui Zhang Yongqiang feng yu liu Department of Bum Provincial Hospital Affiliated to Shandong University Jinan 250021 Shandong Province China Department of Bum Weihai Municipal Hospital Weihai 264200 Shandong Province China Department of Pathology Shandong Medical College Jinan 250002 shandong Province China Department of Pathology Provincial Hospital Affiliated to Shandong University Jinan 250021 Shandong Province China

BACKGROUND： Numerous studies use fluorescent microscopy to obtain two-dimensional optical images of the morphology of nerve fibers in hypertrophic scars. In addition, current confocal microscopy studies have focused on normal, not pathological, cutaneous nerves. However, laser scanning confocal microscopy results in a three-dimensional structure of the nerve fibers. OBJECTIVE： To observe quantitative and morphological differences in nerve fibers from the proliferative and mature stage in hypertrophic scars using fluorescent and confocal microscopy. DESIGN, TIME AND SETTING： Neuropathological, comparison study was conducted at the Provincial Hospital Affiliated to Shandong University, China from June 2006 to July 2007. PARTICIPANTS： Specimens were selected from 30 patients undergoing scar restoration at the Provincial Hospital Affiliated to Shandong University of China at 1 month to 23 years following wound healing. The study comprised 20 males and 10 females. The scars were fibrous lesions, erythematous, tough, confined to skin lesions, did not exhibit ulceration or infection, exhibited telangiectasia, with or without itching and pain, and were not locally treated. Samples were equally assigned to two groups according to course of disease： proliferative group （〈 6 months） and mature group （6-24 months）. Control samples were collected from full-thickness skin from donor sites （n = 10）. METHODS： Nerve fiber morphology was observed using fluorescent and confocal microscopy following immunofluorescence of the skin specimens. The microscopic images were semi-quantitatively analyzed to acquire a positive area ratio of neurofilament protein-positive nerve fibers. MAIN OUTCOME MEASURES： Morphology and positive area ratio of neurofilament protein/positive nerve fibers was measured. RESULTS： The positive area ratio of neurofilament protein-positive nerve fibers was significantly greater in the proliferative group compared to the normal control group （P 〈 0.05）. Nerve fibers w

关键词： scar hypertrophic neurofilament proteins innervation nerve regeneration

Controlling of coordination state of Ru_(x)N_(y) clusters for efficient oxygen reduction electrocatalysis

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Nano Research 2024年第3期17卷 1035-1041页

作者： Weiyang Fu Yihuan yu Tongtong liu Yinliang cao Zhengping Zhang feng Wang State Key Laboratory of Chemical Resource Engineering Beijing Key Laboratory of Electrochemical Process and Technology for MaterialsBeijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Zhejiang Tianneng Hydrogen Energy Technology Co. Ltd.Huzhou 313100China

Ruthenium(Ru)is an attractive potential alternative to platinum as an electrocatalyst for the oxygen reduction reaction(ORR),in virtue of its high catalytic selectivity and relatively low *** this work,a series of well-dispersed nitrogen-coordinated Ru-clusters on carbon black(Ru_(x)N_(y)/C)were prepared by pyrolyzing different Ru-containing sandwich compounds as the Ru *** higher thermal stability of these complexed sandwich precursors(bis(1,2,3,4,5-pentamethylcyclopentadienyl)Ru(II)monomer,dichloro(p-cymene)Ru(II)dimer,and chloro(1,2,3,4,5-pentamethylcyclopentadienyl)Ru(II)tetramer)affords the control of coordinated state for the resulting Ru-clusters,in comparison of that derived from ruthenium *** the pyrolysis treatment,the Ru coordinated state in Ru_(x)N_(y)/C,with the Ru–N and Ru–Ru bonds,still showed the structural inheritance from the Ru(II)monomer,dimer,and tetramer,but using ruthenium chlorides as the Ru source resulted in the nanoscale Ru *** ORR testing exhibited that the Ru_(x)N_(y)/C sample derived from the Ru(II)tetramer(Ru_(x)N_(y)/C-T)presents the higher catalytic activity than the other obtained samples in either alkaline or acidic *** in the acidic electrolyte,Ru_(x)N_(y)/C-T shows the comparable ORR activity to that of Pt/C catalysts,and it shows the superior tolerance against methanol and *** X-ray absorption spectroscopy and density functional theory calculations demonstrate that these tetra-nuclear Ru-clusters could be the most active site due to their broadened d-orbital bands and lower energy d-band center than those of other subnano species and nanocrystals,and their favorable Yeager-type adsorption of O_(2)-molecules is also contributed to promoting O–O bond cleavage and accelerating the ORR process.

关键词： ruthenium clusters coordination environment sandwich compounds electrocatalysis oxygen reduction reaction

Infuence of Composition on Self-toughening and Oxidation Properties of Y-a-Sialons

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Journal of Materials Science & Technology 2013年第10期29卷 983-988页

作者： Chunfeng liu feng Ye Rongsen xia Lei Zhang yu Zhou yudong Huang Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of Technology School of Chemical Engineering and Technology Harbin Institute of Technology

Y-α-sialon ceramics with different compositions were hot-press sintered. Varying the m or n value in theα-Sialon general formula, both the α-sialon grain morphology and phase assemblages present diversification, therefore, affecting the toughness and hardness. Meanwhile, varying the compositional parameters also influenced the composition and structure of the intergranular glass phase, as well as its oxidation behavior at 1100-1200 ℃. The oxidation of the intergranular phase Mt in the Y-α-sialon ceramics was significantly enhanced with further rising the oxidation temperature to 1300 ℃.

关键词： α-Sialon ceramics Oxidation Y203 Self-reinforcement