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Chinese Journal of Polymer Science 2014年第3期32卷 371-376页

作者：曹靖 jun-xiang Feng 吴诗 College of Chemistry Xiangtan University School of Pharmacy Hubei University of Science and Technology

Novel conjugated polymers with aza-15-crown-5 as pendant groups, P1 were synthesized by the Sonogashira coupling reaction. The polymer P1 was found to show fluorescence en-hancement response towards Ba2＋. The gradual recovery and turning-point of emission intensity of polymers appeared in the addition of Ba2＋, which provided good evidence for the fluorescence amplification mechanism of conjugated polymers.

关键词： Conjugated polymer Fluorescence recovery,

GSM-MRF based classification approach for real-time moving object detection

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 250-255页

作者： xiang PAN Yi-jun WU Institute of Information and Communication Engineering Zhejiang University Hangzhou 310027 China

Statistical and contextual information are typically used to detect moving regions in image sequences for a fixed *** this paper,we propose a fast and stable linear discriminant approach based on Gaussian Single Model(GSM)and Markov Random Field(MRF).The performance of GSM is analyzed first,and then two main improvements corresponding to the drawbacks of GSM are proposed:the latest filtered data based update scheme of the background model and the linear classification judgment rule based on spatial-temporal feature specified by *** results show that the proposed method runs more rapidly and accurately when compared with other methods.

关键词： Moving object detection Markov Random Field (MRF) Gaussian Single Model (GSM) Fisher Linear Discriminant Analysis (FLDA)

Alloying Design for High Wear-Resistant Cast Hot-Forging Die Steels

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Journal of Iron and Steel Research International 2008年第4期15卷 67-72页

作者： CUI xiang-hong shan jun YANG Zi-run WEI Min-xian WANG Shu-qi DONG Chuang School of Materials Science and Engineering Jiangsu University Zhenjiang 212013 Jiangsu China Harbin Zhuoyue Information Technology Advance Limited Company Harbin 150001 Heilongjiang China State Key Laboratory of Materials Modification by Laser Ion and Electron Beams Dalian University of Technology Dalian 116024 Liaoning China

The alloying design of cast hot-forging die steels was analyzed. The relationship of the life of cast hot-forging dies with the failure patterns was studied. The thermal wear resistance was believed to be the key property for the alloying design of cast hot-forging die steels. The alloying design parameters were selected and optimized for the cast hot-forging die steel with high wear resistance. The wear resistance of the optimized cast die steel was evaluated in comparison with commercial H13 steels and 3Cr2WSV steel. In the new cast hot-forging die steel, VC is predominant carbide with Cr and Mo as the main solution elements in α-Fe. It is found that the cast die steel has significantly lower wear rate than normal H13 steel and 3Cr2W8V steel, almost the same as that of high purity H13 steel. The high wear resistance of the new cast hot-forging die steel can be attributed to its reasonable alloying design and nonsensibility to the detrimental function of S and P.

关键词： hot-forging die cast steel wear resistance alloying design

Ultrasonographic measurement of median nerve cross-sectional area reference values in a healthy Han population from Guiyang,China

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Neural Regeneration Research 2011年第24期6卷 1883-1887页

作者： jun Chen shan Wu jun Ren Department of Neurology Affiliated Hospital of Guiyang Medical College Guiyang 550004 Guizhou Province China University of Wyoming College of Health Sciences Wyoming INBRE Program Laramie WY 82071 USA

High-resolution ultrasonography was used to analyze the nerve cross-sectional area （CSA） of the median nerve at 7 sites： the wrist crease, pisiform bone, hamate bone, 6 cm proximal to the tip of the wrist crease, proximal forearm （where the nerve enters the pronator teres muscle）, 4 cm proximal to the tip of the medial epicondyle, and mid-humerus （mid-point between elbow crease and axilla） in 200 healthy volunteers from Guiyang, China. Results showed similar CSA values between the left and right sides, but the CSA 6 cm proximal to the tip of the wrist crease, proximal forearm, 4 cm proximal to tip of the medial epicondyle, and mid-humerus in males was greater than that of females. Moreover, CSA values at the wrist crease, pisiform bone, and hamate bone were greater in the middle-aged and old groups when compared to the young group, and correlated with body mass and height. Thus, reference values of median nerve CSA of the upper limbs can facilitate the analysis of abnormal nerve conditions.

关键词： ultrasonography median nerve cross-sectional area Guiyang Han nationality

A Novel Design of a Pre-separation Panel Structure to Protect Against the Impact of an Explosion in an Aircraft Plenum Chamber

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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing Liu xiang Yang jun Liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast ***,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage ***,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation ***,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact *** calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the *** residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged *** results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location

Effect of Al_2O_3 Binder on the Precipitated Iron-Based Catalysts for Fischer-Tropsch Synthesis

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Journal of Natural Gas Chemistry 2007年第2期16卷 130-138页

作者： Hai-jun Wan Bao-shan Wu Xia An Ting-Zhen Li Zhi-Chao Tao Hong-Wei xiang Yong-Wang Li State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 Shanxi China Graduate University of Chinese Academy of Sciences Beijing 100039 China

A series of iron-based Fischer-Tropsch synthesis （FTS） catalysts incorporated with Al2O3 binder were prepared by the combination of co-precipitation and spray drying technology. The catalyst samples were characterized by using N2 physical adsorption, temperature-programmed reduction/desorption （TPR/TPD） and MSssbauer effect spectroscopy （MES） methods. The characterization results indicated that the BET surface area increases with increasing Al2O3 content and passes through a maximum at the Al2O3/Fe ratio of 10/100 （weight basis）. After the point, it decreases with further increase in Al2O3 content. The incorporation of Al2O3 binder was found to weaken the surface basicity and suppress the reduction and carburization of iron-based catalysts probably due to the strong K-Al2O3 and Fe-Al2O3 interactions. Furthermore, the H2 adsorption ability of the catalysts is enhanced with increasing Al2O3 content. The FTS performances of the catalysts were tested in a slurry-phase continuously stirred tank reactor （CSTR） under the reaction conditions of 260 ℃, 1.5 MPa, 1000 h^-1 and molar ratio of H2/CO 0.67 for 200 h. The results showed that the addition of small amounts of Al2O3 affects the activity of iron-based catalysts to a little extent. However, with further increase of Al2O3 content, the FTS activity and water gas shift reaction （WGS） activity are decreased severely. The addition of appropriate Al2O3 do not affect the product selectivity, but the catalysts incorporated with large amounts of Al2O3 have higher selectivity for light hydrocarbons and lower selectivity for heavy hydrocarbons.

关键词： Fischer-Tropsch synthesis iron-based catalyst Al2O3 binder Fe-Al2O3 interaction

A Lightweight Anonymous Device Authentication Scheme for Information-Centric Distribution Feeder Microgrid

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Computers, Materials & Continua 2021年第11期69卷 2141-2158页

作者： Anhao xiang jun Zheng Department of Computer Science and Engineering New Mexico Institute of Mining and TechnologySocorro87801NMUSA

Distribution feeder microgrid(DFM)built based on existing distributed feeder(DF),is a promising solution for modern *** contains a large number of heterogeneous devices that generate heavy network traffice and require a low data delivery *** information-centric networking(ICN)paradigm has shown a great potential to address the communication requirements of smart ***,the integration of advanced information and communication technologies with DFM make it vulnerable to cyber *** authentication of grid devices is essential for preventing unauthorized accesses to the grid network and defending against cyber *** this paper,we propose a new lightweight anonymous device authentication scheme for DFM supported by named data networking(NDN),a representative implementation of *** perform a security analysis to show that the proposed scheme can provide security features such as mutual authentication,session key agreement,defending against various cyber attacks,anonymity,and resilience against device capture *** security of the proposed scheme is also formally verified using the popular AVISPA(Automated Validation of Internet Security Protocols and Applications)*** computational and communication costs of the proposed scheme are *** results demonstrate that the proposed scheme achieves significantly lower computational,communication and energy costs than other state-of-the-art schemes.

关键词： Mutual authentication information-centric networking named data networking distribution feeder microgrid smart devices AVISPA security

Coupled Solitons in Alternating Heisenberg Ferromagnetic Chains with a Small Magnon Band Gap

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Chinese Physics Letters 2001年第10期18卷 1316-1318页

作者： ZHU shan-Hua HUANG Guo-xiang Key Laboratory for Optical and Magnetic Resonance Spectroscopy and Department of Physics East China Normal UniversityShanghai 200062 Physics Group Zhuzhou Institute of TechnologyZhuzhou 412008

The coupled soliton excitations in an alternating Heisenberg ferromagnetic chain with a small magnon band gap are considered. Based on a quasi-discrete multiple scale approach, a set of coupled mode equations is derived which describes the dynamics of strongly coupled acoustic upper cut-off and optical lower cut-off modes. Coupled magnetic band gap soliton solutions are explicitly provided and their frequency properties are discussed.

关键词： Heisenberg soliton magnetic

Biological Evaluation of Lysionotin:a Novel Inhibitor of 5-Lipoxygenase for Anti-glioma

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Chinese Journal of Integrative Medicine 2024年第9期30卷 826-834页

作者： SHAO Xin-xin CHEN Cong LIU Jie LI Qing-jun HE shan QI xiang-hua FU Xian-jun WANG Zhen-guo The First Clinical College of Medicine Shandong University of Traditional Chinese MedicineJinan250355China Institute for Literature and Culture of Chinese Medicine Shandong University of Traditional Chinese MedicineJinan250355China Key Laboratory of Classical Theory of Traditional Chinese Medicine Ministry of EducationShandong University of Traditional Chinese MedicineJinan250355China College of Pharmacy Shandong University of Traditional Chinese MedicineJinan250355China Experimental Center Shandong University of Traditional Chinese MedicineJinan250355China Neurology Department Affiliated Hospital of Shandong University of Traditional Chinese MedicineJinan250014China Marine Traditional Chinese Medicine Research Center Qingdao Academy of Traditional Chinese MedicineShandong University of Traditional Chinese MedicineQingdao266114Shandong ProvinceChina

Objective:To explore the potential mechanism of lysionotin in treating ***:First,target prediction based on Bernoulli Naïve Bayes profiling and pathway enrichment was used to predict the biological activity of *** binding between 5-lipoxygenase(5-LO)and lysionotin was detected by surface plasmon resonance(SPR)and molecular docking,and the inhibitory effects of lysionotin on 5-LO and proliferation of glioma were determined using enzyme inhibition assay in vitro and cell viability analysis,***,the pharmaceutical effect of lysionotin was explored by cell survival rate analysis and liquid chromatography with tandem mass spectrometry(LC-MS/MS).The protein expression,intracellular calcium ion concentration and cytoskeleton detection were revealed by Western blot,flow cytometry and fluorescence labeling,***:Target prediction and pathway enrichment revealed that lysionotin inhibited 5-LO,a key enzyme involved in the arachidonic acid metabolism pathway,to inhibit the proliferation of *** docking results demonstrated that 5-LO can be binding to lysionotin through hydrogen bonds,forming bonds with His600,Gln557,Asn554,and *** analysis further confirmed the interaction between 5-LO and ***,enzyme inhibition assay in vitro and cell survival rate analysis revealed that 50%inhibition concentration of lysionotin and the median effective concentration of lysionotin were 90 and 16.58µmol/L,respectively,and the results of LC-MS/MS showed that lysionotin inhibited the production of 5S-hydroperoxy-eicosatetraenoic acid(P<0.05),and moreover,the LC-MS/MS results indicated that lysionotin can enter glioma cells well(P<0.01)and inhibit their *** blot analysis demonstrated that lysionotin can inhibit the expression of 5-LO(P<0.05)and downstream leukotriene B4 receptor(P<0.01).In addition,the results showed that lysionotin affected intracellular calcium ion concentration by inh

关键词： 5-lipoxygenase inhibitor lysionotin 5-lipoxygenase leukotriene B4 calcium ion cytoskeleton

Yield Evaluation of Twenty-Eight Alfalfa Cultivars in Hebei Province of China

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Journal of Integrative Agriculture 2014年第10期13卷 2260-2267页

作者： ZHANG Tie-jun KANG jun-mei GUO Wen-shan ZHAO Zhong-xiang XU Yu-peng YAN Xu-dong YANG Qing-chuan Institute of Animal Science Chinese Academy of Agricultural Sciences Cangzhou Technical College

Cultivar selection is important for alfalfa （Medicago sativa L.） hay production. From 2009 to 2012, a field study was conducted to evaluate the dry matter yield （DMY） of 28 cultivars in Cangzhou District of Hebei Province, China, and to determine the most suitable cultivars for this province and other zones with similar climate conditions. 28 alfalfa cultivars were sown in late March of 2009 and were harvested for hay four times in each subsequent year. The results showed that the climatic conditions resulted in significant differences in annual DMY among years, with the second year being the highest and the first year the lowest. The top five cultivars with the highest total DMY were L2750 （62.75 t ha^-1）, Hom （62.72 t ha^-1）, 86-266 （61.55 t ha^-1）, German （61.44 t ha^-1） and Zhongmu 1 （61.18 t ha^-1）, respectively. Across all four years, first harvest had the highest ratios to annual DMY except the cultivar of Rambler, while the fourth harvest had the lowest ratio. There were positive correlation relationships between DMY of each harvest and annual DMY, and the correlation coefficients were all significant in four years. And the path coefficients of first harvest were always the highest in four years. The qualities showed small variations among these cultivars and the cultivar L3750 presented the highest crude protein in both years. Crude protein had significant positive correlation with relative feed value （RFV） in both years while crude fiber had significant negative correlation with RFV and crude fiber.

关键词： alfalfa cultivars yield forage quality