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Science Letters:A synthetic Toll-like receptor 2 ligand decreases allergic immune responses in a mouse rhinitis model sensitized to mite allergen

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Journal of Zhejiang University-Science B(biomedicine & biotechnology) 2008年第4期9卷 279-285页

作者： cheng ZHOU Xiao-dong KANG Zhi CHEN Institute of Infectious Diseases the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Experimental Animal Center School of Medicine Hangzhou Teacher＇s College Hangzhou 310018 China

It has been proposed that activation of Toll-like receptors （TLRs） plays crucial roles in the polarization of adaptive immune responses. A synthetic Toll-like receptor 2 （TLR2） ligand, Pam3CSK4, has been reported to modulate the balance of Th1/Th2 responses. We evaluated the modulation effect of Pam3CSK4 on allergic immune response in a mouse rhinitis model sensitized to house dust mite allergen （HDM）. Mice were sensitized and challenged with Dermatophagoidesfarinae allergen （Der f）, and then the allergic mice were treated by Pam3CSK4. Nasal allergic symptoms and eosinophils were scored. Der f-specific cytokine responses were examined in the splenocytes and bronchoalveolar lavage fluid （BALF）. Serum level of total IgE was also detected. After establishing a mouse allergic rhinitis model with HDM, we have showed that Pam3CSK4 treatment not only ameliorated the nasal allergic symptoms remarkably but also decreased the eosinophils and total inflammation cells in BALF significantly. Analysis of cytokine profile found that IFN-7 released from either BALF or stimulated splenocytes increased markedly in Pam3CSK4-treated mice, while IL-13 decreased significantly. Moreover, serum level of total IgE was significantly lower in Pam3CSK4-treated mice than in the untreated. Thus, in an allergic rhinitis mouse model developed with HDM, Pam3CSK4 was shown to exhibit an antiallergic effect, indicating its potential application in allergic diseases.

关键词： Toll-like receptor 2 (TLR2) Ligand Allergic immune response Mite allergen

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Insensitive energetic microspheres DAAF/RDX fabricated by facile molecular self-assembly

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Defence Technology（防务技术） 2021年第5期17卷 1775-1781页

作者： Shu-jie Liu bi-dong Wu Jia-ni Xie Zhi-min Li Chong-wei An Jing-yu Wang Xiao-dong Li School of Environment and Safety Engineering North University of ChinaShanxi030051China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

Insensitive energetic materials are promising in the defense weapons ***,energetic materials still suffer from great challenges and the concern about their safety limits their *** this work,insensitive energetic explosive 3,30-diamino-4,40-azoxyfurazan/hexahydro-1,3,5-trinitro-1,3,5-triazine(DAAF/RDX)microspheres were fabricated by self-assembly ***-like DAAF/RDX was prepared by mechanical ball milling for ***/RDX composites with different mass ratios(90:10,80:20,and 70:30)were *** morphologies and structures of as-obtained DAAF/RDX composites were characterized by scanning electron microscopy(SEM),powder x-ray diffraction(PXRD)and fourier transform infrared spectroscopy(FT-IR).The results showed that DAAF/RDX microspheres exhibited regular shaped microspheres with sizes from 0.5 to 1.2 *** was no crystal transition during the modification *** thermal properties of as-obtained materials were then evaluated by differential scanning calorimetry(DSC)and materials studio ***/RDX microspheres showed an advanced decomposition peak temperature compared with rod-like DAAF/*** binding energy and peak temperature values at zeroβ_(i)(T_(P0))of DAAF/RDX(90:10)increased by 36.77 kJ/mol,1.6℃,and 58.11 kJ/mol,12.3℃compared to DAAF/RDX(80:20)and DAAF/RDX(70:30),indicating the better thermal stability of DAAF/RDX(90:10).The characteristic drop height(H_(50))of DAAF/RDX(higher than 100 cm)composites was higher than that of raw RDX(25 cm),suggesting significant improvements in mechanical *** preparation of DAAF/RDX microspheres is promising for the desensitization of RDX and useful for the formation of other materials and future wide applications.

关键词： DAAF RDX Insensitive Energetic microspheres Thermal stability

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Numerical study of short-circuiting flow and particles in a gas cyclone

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Particuology 2023年第1期72卷 81-93页

作者： Sijie dong Chenwen Wang Zihui Zhang Qinyu Cai Kejun dong Teng cheng Bo Wang Key Laboratory of Western China’s Environmental Systems of Ministry of Education Engineering Research Center of Fine Particle Pollution Control Technology and Equipment of Gansu ProvinceCollege of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Key Laboratory of Resource Environment and Sustainable Development of Oasis of Gansu Province College of Geography and Environmental ScienceNorthwest Normal UniversityLanzhou 730000China Center for Infrastructure Engineering Western Sydney UniversityPenrithNSW 2751Australia

Short-circuiting flow is an important secondary flow in gas cyclones, which has a negative impact on the separation performance. To improve the understanding of the short-circuiting flow and guide the optimization of gas cyclones, this paper presents a numerical study of a cyclone using computational fluid dynamics. Based on the steady flow field, three methods were adopted to investigate the formation mechanism and characteristics of the short-circuiting flow and particles. The temporal variation of the tracer species concentration distribution reveals that the formation mechanism of the short-circuiting flow is the squeeze between the airflows entering the annular space of the gas cyclone at different times. The short-circuiting flow region, distinguished through the spatial distribution of the moments of age, is characterized by a small mean age and a large coefficient of variation. The proportion of the short-circuiting particles increases with the increase of the inlet velocity only for small particles. But with the increase of particle size, the proportion of the short-circuiting particles decreases faster at higher inlet velocities, resulting in significant differences in collection efficiency curves.

关键词： Gas cyclone Short-circuiting flow Computational fluid dynamics Species transport Moment of age Particle tracking

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Analysis of the factors affecting thermal evolution of hot rolled steel during coil cooling

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Journal of University of Science and Technology Beijing 2006年第2期13卷 139-143页

作者： Jiefeng cheng Zhengdong Liu Han dong Yong Gan Central Iron and Steel Research Institute Beijing 100081 China

The thermal evolution of steel coil during cooling was simulated and investigated by the use of in-house Q-CSP software. The dependence of the thermal evolution of steel coil on cooling methods, temperature distribution of the strip before coiling, coil size and steel grades was also discussed. The study plays a significant role in helping steel makers to better understand and control the cooling process.

关键词： steel coil temperature distribution cooling method simulation

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Zircon U-Pb Ages and Sr-Nd-Hf Isotopic Characteristics of the Huichizi Granitic Complex in the North Qinling Orogenic Belt and Their Geological Significance

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Journal of Earth Science 2018年第3期29卷 492-507页

作者： Youwei Chen Ruizhong Hu Xianwu bi Shaohua dong Yue Xu Ting Zhou State Key Laboratory of Ore Deposit Geochemistry Chinese Academy of Sciences

The Huichizi granite complex is the largest Paleozoic 1-type intrusion located in the North Qinling orogenic belt （NQB）. In this study, we present systematic geochemical element data, zircon U-Pb ages, Ln-Hf isotopic data, and Sr-Nd isotopic data for the Huichizi granites. In terms of mineral and chemical compositions, these granites are biotite monzonitic and alkali-feldspar granites, both of which are characterized by high SiO2 and total alkali contents and low MgO, TiO2, and TFeO contents. These granites are weakly peraluminous （A/CNK values are 1-1.06 for biotite mon- zonitic granites and 1.04-1.09 for alkali-feldspar granites） and possess the geochemical characteristics of adakitic rocks, e.g., high Sr contents （319 ppm-633 ppm）, Sr/Y ratios （18.5-174）, and （La/Yb）N ratios （17.6-57） and low MgO （0.04 wt.%-0.83 wt.%）, Y （3.0 ppm-17.2 ppm）, and heavy rare-earth element （HREE） contents. This indicates that these rocks were most likely derived from the partial melting of a thickened lower crust. In situ zircon U-Pb dating of these granites yields Early Caledonian ages （437 Ma for biotite monzonitic granites and 424 Ma for alkali-feldspar granites）, indicating that the Huichizi granitic complex is the product of multi-periodic magmatism. The positive but varying zircon tHe（t） values （＋0.6 to ＋8.5） suggest that this thickened lower crust was mainly juvenile, i.e., accreted from depleted mantle during the Neo-Mesoproterozoic Period, but involved the ancient recycled crust. biotite monzonitic granites formed during crust thickening at the extrusion stage, whereas the alkali granites formed during crust thickening at the extension stage （post extrusion）. The Huichizi granite complex witnessed the process of extrusion to extension because of the collision between the NCB and the Qinling microcontinent in the Caledonian.

关键词： U-Pb age Sr-Nd-Hf isotope Huichizi granitic complex adakitic granite North Qinling orogen.

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Environmental Simulation Experiments of 3D-C/SiC Composites with Different PyC Interfacial Layers

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Journal of Materials Science & Technology 2003年第z1期19卷 77-80页

作者： Ning dong Yongdong XU Laifei cheng Litong ZHANG State Key Laboratory of Solidification Northwestern Polytechnical University Xi′an 710072 China State Key Laboratory of Solidification Northwestern Polytechnical University Xi′an 710072 China State Key Laboratory of Solidification Northwestern Polytechnical University Xi′an 710072 China State Key Laboratory of Solidification Northwestern Polytechnical University Xi′an 710072 China

A series of 3D-C/SiC composites with different pyrolytic carbon (PyC) interracial layers (about 20～300 nm thick)were prepared by chemical vapor infiltration. Simulation experiments at different temperatures were performed byexposing C/SiC specimens in single and coupling gases partial pressure atmospheres, namely, O2, H2O vapor andmolten salt (Na+) vapor. It suggested that at intermediate temperature range (about 600～800℃) a dramatic effectof PyC thickness on the weight and strength change of C/SiC was shown, which was mainly influenced by O2 partialpressure; at high temperature range (about 1200～1300℃) the effect was not obvious relatively, which might beinfluenced by H2O vapor partial pressure; and finally at very high temperature range (＞1500℃) the molten saltvapor was the factor of most possibility affecting the weight change of C/SiC.

关键词： C/SiC, Interfacial layer, Simulation experiment

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Novel Terpolymers of Poly(p-dioxanone-co-trimethylene carbonate-co-Lphenylalanine)： Synthesis, Characterization, Thermal Properties and Copolymerization Mechanism

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Chinese Journal of Polymer Science 2016年第5期34卷 594-605页

作者： Li-nan Li cheng-dong Xiong 陈栋梁 chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China University of Chinese Academy of Sciences Beijing 100049 China

In order to exploit the biological functions of materials, a series of new random terpolymers were synthesized by the ring-opening polymerization of p-dioxanone, trimethylene carbonate, and L-phenylalanine N-carboxyanhydride（L-PheNCA） in the presence of stannous octoate. The terpolymers were characterized by 1H-NMR, 13C-NMR, FTIR, and gel permeation chromatography. The effects of the reactant ratio, catalyst dosage, reaction temperature and time on the copolymerization were investigated, and were found to regulate the composition of the terpolymer. Increases in the reaction temperature, polymerization time, L-Phe-NCA monomer amount, and catalyst content generated a product with a slightly decreased molecular weight. The crystallinity of the terpolymer was investigated by differential scanning calorimetry and polarized optical microscopy. A reasonable mechanism for the polymerization was proposed based on the obtained results.

关键词： polymerization crystallinity calorimetry permeation monomer phenylalanine carbonate slightly dosage biodegradable

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Electrodynamic response study on railgun launcher based on electromechanical coupling model

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Defence Technology（防务技术） 2019年第4期15卷 655-665页

作者： Hong-cheng Xiao dong-mei Yin Bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and Technology

The electrodynamic behavior of a medium caliber railgun launcher has been studied based on an electromechanical coupling model,which uses a unified modeling method for both electromagnetic and electromechanical *** model adopts a material equivalent method to simulating the sliding contact behavior for the in-bore *** embedded node encoding program during field meshing operation provides good load transfer accuracy between electromagnetic field and mechanical *** properties of in-bore magnetic field are firstly simulated and a subsequent dynamic analysis is conducted by mapping element results from electromagnetic analysis step to structure analysis *** electromechanical-elastic response of the barrel is studied under the excitation *** numerical model has shown reliability compared to experimental results.

关键词： Railgun launcher Sliding contact Dynamic properties Elastic response

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Catalytic Oxidation of Hexanol to Hexanal with H_2O_2 Over P-W Heteropoly Compounds

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Chemical Research in Chinese Universities 2001年第3期17卷 293-298页

作者： ZHOU Guang-dong GUO Xiao-hong LIU Yan bi Ying-li ZHEN Kai-ji Department of Chemistry Jilin UniversityChangchun 130023P.R.China

The syntheses of Keggin and Dawson-structural phospho-tungsto heteropoly compounds and their Peroxo-derivatives(PCWP), and the catalytic performance over this series of catalysts for the selective oxidation of hexanol to hexylaldehyde are reported. By means of IR, NMR and UV-DRS techniques the catalysts were characterized and a comparison of the structural properties of these catalysts before and after the reaction was made. The correlation between the catalytic performance and the structure of this series of catalysts was discussed as well.

关键词： P-W Heteropoly compound Hexanol Hexanal

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Mechanism of α-Cr precipitation and crystallographic relationships between α-Cr and δ phases in Inconel 718 alloy after long-time thermal exposure

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International Journal of Minerals,Metallurgy and Materials 2010年第3期17卷 312-317页

作者： Zhong-nan bi Jian-xin dong Mai-cang Zhang Lei Zheng Xi-shan Xie School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

To study the precipitation mechanism of α-Cr phase in Inconel 718 alloy, the samples after long-time aging at 650 and 677℃ were examined by microstructural observations and chemical phase analysis methods. Combining the thermodynamics and kinetics calculation results, α-Cr always precipitates in the vicinity of δ phase, because δ phase rejects Cr into the γ-matrix when growing. The selected area diffraction patterns confirm that the crystallographic relationships of α-Cr with 6 phase are （010）d/（1- 10）*** and [100]d/If 11 ]α-Cr- A graphic model is also presented to show the crystallographic relation between α-Cr and δ phases.

关键词： Inconel 718 precipitation mechanism crystallography thermodynamics kinetics

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