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Defence Technology（防务技术） 2020年第4期16卷 747-752页

作者： chun-yan zhu Bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyChina

The contact resistance between the armature and rails is an important indicator of the contact characteristics in electromagnetic *** the contact resistance depends not only on the contact state but also on the contact stress and temperature,there are some limitations in analyzing the contact characteristics using only the contact *** this paper,the contact characteristics of the augmented railgun are analyzed by the combination of contact resistance and sliding friction ***,the theoretical calculation model of the contact resistance and friction coefficient of the augmented electromagnetic railgun is *** the contact resistance and friction coefficient are calculated by the measured values of the muzzle voltage,rail current and armature ***,the contact characteristics are analyzed according to the features of the waveforms of the contact resistance and the friction coefficient,and the analysis conclusions are verified by experimental rail *** results showed that:the aluminum melt film gradually formed on the contact surface reduces the contact resistance and the friction coefficient;the wear and erosion of the armature cause deterioration of the contact state;after the transition,the reliability of the sliding contact between the armature and rails decreases,resulting in an increase in contact resistance.

关键词： Augmented railgun Contact resistance Friction coefficient Contact characteristics

INDUCED CRYSTALLIZATION BEHAVIOR OF POLY(ETHYLENE ADIPATE) BY HIGHLY ORIENTED POLYETHYLENE

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Chinese Journal of Polymer Science 2013年第8期31卷 1173-1182页

作者： chun-zhu yan Lin Guo 常海波闫寿科 School of Chemistry and Environment Beihang University Chemistry and Chemical Engineering College Henan University State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

The crystallization behavior of poly（ethylene adipate）（PEA） on highly oriented high-density polyethylene （PE） substrate both from solution and isotropic melt was studied by means of optical microscopy, differential scanning calorimetry, atomic force microscopy and electron diffraction. The results show that the PE influences the crystallization of PEA strongly, which results in an epitaxial growth of PEA with well ordered structure. At the boundary of the PE substrate, a transcrystalline PEA layer is observed. Fine structural observation illustrates that the PEA grows on the PE substrate in edge- on lamellae with fixed orientation. Electron diffraction demonstrates that the epitaxial organization of PEA on PE occurs with both polymer chains parallel, which leads to the （00l） PEA diffractions inclined ±23.5° to the chain direction of PE crystals. Combining the real space morphological observation and electron diffraction results, it is concluded that the epitaxial PEA edge-on lamellae are folded in the {00l} lattice planes.

关键词： Poly(ethylene adipate) Polyethylene Epitaxy Orientation.

TEMPERATURE-DRIVEN SURFACE MORPHOLOGY EVOLUTION OF POLY(3-HYDROXYBUTYRATE) SINGLE LAYER AND POLY(3-HYDROXYBUTYRATE)/POLY(VINYL PHENOL) BILAYER ON Si WAFERS

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Chinese Journal of Polymer Science 2013年第3期31卷 407-418页

作者： chun-zhu yan Lin Guo 孙晓丽闫寿科 Isao Takahashi School of Chemistry and Environment Beihang University State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology School of Science and Technology Kwansei Gakuin University

The specular and off-specular X-ray reflectivities were efficiently employed to study the evolution of surface morphology as a function of temperature in a single layer of poly（3-hydroxybutyrate）（PHB） and a bilayer of PHB/poly（vinyl phenol）（PVPh） on Si substrates. The results indicate that the changes of thickness and surface roughness caused by pre-melting of PHB crystals are not obvious for the single layer, whereas the surface roughness of the PHB layer and the intensity of the off-specular X-ray reflectivity for the bilayer exhibit a remarkable non-monotonic change in the temperature range of 100-150℃; the roughness parameter evaluated by the specular X-ray reflectivity reaches its maximum at 120℃. The interaction at the interface between PVPh and PHB certainly contributes to the non-monotonic changes. Such interaction also affects the crystallization and melting behavior of PHB thin film greatly. The crystallization of PHB thin film is inhibited even on the glassy surface of PVPh sublayer, In the melting process, the PHB crystals on PVPh sublayer feature a threesection melting curve separated by a plateau region of 120-140℃.

关键词： Interface Hydrogen-bond Roughness Melt.

Magnetic resonance imaging of the zone of calcified cartilage in the knee joint using 3-dimensional ultrashort echo time cones sequences

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Chinese Medical Journal 2019年第5期132卷 562-568页

作者： Jin Liu yang Wei Ya-Jun Ma yan-chun zhu Quan Zhou Ying-Hua Zhao Department of Radiology Third Affiliated Hospital of Southern Medical University (Academy of Orthopedics Guangdong Province) Guangzhou Guangdong 510630 China Guangdong Provincial Key Laboratory of Medical Image Processing School of Biomedical Engineering Southern Medical University Guangzhou Guangdong 510515 China Department of Radiology University of CaliforniaSan DiegoSan DiegoCAUSA

Background: The zone of calcified cartilage (ZCC) plays an important role in the pathogenesis of osteoarthritis (OA) but has never been imaged in vivo with magnetic resonance (MR) imaging techniques. We investigated the feasibility of direct imaging of the ZCC in both cadaveric whole knee specimens and in vivo healthy knees using a 3-dimensional ultrashort echo time cones (3D UTE-Cones) sequence on a clinical 3T scanner. Methods: In all, 12 cadaveric knee joints and 10 in vivo healthy were collected. At a 3T MR scanner with an 8-channel knee coil, a fat-saturated 3D dual-echo UTE-Cones sequence was used to image the ZCC, following with a short rectangular pulse excitation and 3D spiral sampling with conical view ordering. The regions of interests (ROIs) were delineated by a blinded observer. Singlecomponent T2* and T2 values were calculated from fat-saturated 3D dual-echo UTE-Cones and a Carr-Purcell-Meiboom-Gill (T2 CPMG) data using a semi-automated MATLAB code. Results: The single-exponential fitting curve of ZCC was accurately obtained with R2 of 0.989. For keen joint samples, the ZCC has a short T2* ranging from 0.62 to 2.55 ms, with the mean ±standard deviation (SD) of 1.49 ±0.66 ms, and with 95% confidence intervals (CI) of 1.20-1.78 ms. For volunteers, the short T2* ranges from 0.93 to 3.52ms, with the mean±SD of 2.09±0.56 ms, and the 95% CI is 1.43 to 2.74ms in ZCC. Conclusions: The high-resolution 3D UTE-Cones sequence might be used to directly image ZCC in the human knee joint on a clinical 3T scanner with a scan time of more than 10 min. Using this non-invasive technique, the T2* relaxation time of the ZCC can be further detected.

关键词： Ultrashort echo time T2* relaxation time Zone of calcified cartilage Articular cartilage

Physicochemical Properties and Gastric Mucosa Irritation of Cantharidin-hydroxypropyl-β-cyclodextrin Inclusion Complex

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Chinese Herbal Medicines 2012年第3期4卷 224-229页

作者： Lin-na AN Yun-jie DANG chun-hui HU chun-yan zhu Institute of Medicinal Plant Development Chinese Academy of Medical SciencesBeijing 100193China

Objective To increase the solubility and relieve the mucous irritation of cantharidin (CA) by preparing cantharidin-hydroxypropyl-β-cyclodextrin (CA/HP-β-CD) inclusion complex. Methods The inclusion complex was prepared by co-evaporation method and characterized by differential scanning calorimetry (DSC), X-ray diffractometry (XRD), and nuclear magnetic resonance (NMR). Results The disappearance of CA as well as the shift of exothermic peaks shown in DSC results indicated the complexation phenomenon. XRD results showed that the crystalline CA pattern had disappeared, and in NMR results, H-5 shifted from δ 3.731 to 3.695 after complexation and H-2 shifted from δ 3.626 to 3.598, which suggested that part of the drug had entered the HP-β-CD cavity to form an inclusion complex. The solubility increased 10.3 times after complexation and the mucous irritation of CA was relieved remarkably. Conclusion Through complexation with HP-β-CD, the solubility and dissolution rate of CA are improved significantly, and the irritation of musous is relieved.

关键词： cantharidin dissolution hydroxypropyl-β-cyclodextrin mucous irritation solubility

Successful cure of a patient with urosepsis using a combination of extracorporeal membrane oxygenation and continuous renal replacement therapy:A case report and literature review

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Chinese Journal of Traumatology 2020年第6期23卷 372-375页

作者： chun-yan zhu Ai-Jun Pan Qing Mei Ting Chen Department of Critical Care Medicine The First Affiliated Hospital of USTCHefei 230032China Department of Critical Care Medicine The Second People's Hospital of HefeiHefei 230009China

Holmium laser lithotripsy(HLL)is one of the common surgical methods for *** causes minor surgical trauma,but complications are not *** membrane oxygenation(ECMO)treatment of sepsis is common,but venoarterial(VA)-ECMO treatment of urosepsis has not been reported *** this article,we reported a 67-year-old female patient with refractory septic shock caused by HLL under percutaneous nephroscope,involving breathing,heart,kidney and other organs,and organs support treatment was ineffective for the ***,we successfully treated the patient under VA-ECMO with continuous renal replacement therapy(CRRT).Combined ECMO and CRRT may provide a solution for addressing refractory *** we present the case and review relevant literature,so as to provide a treatment strategy for patients with refractory urogenic sepsis and to reduce the mortality rate.

关键词： Extracorporeal membrane oxygenation Continuous renal replacement therapy Sepsis Refractory

Sequence structure controllable polymerization-induced self-assembly

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Science China Chemistry 2024年第1期67卷 390-397页

作者： Zi-Xuan Chang Ren-Man zhu chun-yan Hong Wen-Jian Zhang Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China Key Laboratory of Environment-Friendly Polymeric Materials of Anhui Province Anhui UniversityHefei 230601China

Polymerization-induced self-assembly(PISA)combines synthesis and self-assembly of artificial polymers in one-pot,which brings us one step closer to emulating ***,the reported PISA formulations primarily focus on developing nano-objects with new chemical compositions and rarely on structural regulation of polymers with specific ***,sequence structure controllable polymerization-induced self-assembly(SCPISA)is reported by using 7-(2-methacryloyloxyethoxy)-4-methylcoumarin(CMA)as a *** the copolymerization of 2-hydroxyethyl methacrylate(HEMA)and CMA,controlled incorporation of CMA units into the polymer chains can be realized by programmable light/heat ***-based P(HEMA-co-CMA)copolymers with the same composition but different sequence structures generate a range of ***,the morphologies of the resultant nano-objects can also be controlled by regulating the feed molar ratio of CMA and HEMA,which is similar to the conventional PISA,but the synthesis procedure is obviously simplified in *** versatility of the methodology is further demonstrated by the fabrication of different functional nano-objects with sequence structure-dependent morphologies in SCPISA systems with different functional monomers.

关键词： polymerization-induced self-assembly sequence-controlled polymers PET-RAFT polymerization

Genetic Analysis and Molecular Mapping of Two SMV-Resistance Traits in Soybean:Adult-Plant Resistance and Resistance to Seed Coat Mottling

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Agricultural Sciences in China 2010年第1期9卷 11-18页

作者： WANG Kun LI Wen-fu ZHANG Lei LIU chun-yan zhu Xiao-shuang CHEN Qing-shan HU Guo-hua Agriculture Academy Northeast Agricultural University/Crop Research and Breeding Center of Land-Reclamation of Heilongjiang Province/ National Research Center of Soybean Engineering and Technology/Soil Fertility and Environmental Resources Institute Heilongjiang Academy of Agricultural Sciences Harbin 150090 P.R.China

Soybean mosaic virus （SMV） could lead to adult-plant system diseases, and cause mottling of soybean seeds. Genetic analysis and molecular mapping were conducted using an F2 population and derived F3 families from two crosses of Dongnong 3C624 （susceptible）x Dongnong 8143 （resistant） and Dongnong 3C628 （susceptible）× Tie 6915 （resistant）. Simple sequence repeat （SSR） markers with bulked segregation analysis （BSA） were used to conduct genetic mapping of the resistance to SMV1 in the segregating populations. The results indicated that resistance to SMV1 in adultplants and the resistance to seed coat mottling in Dongnong 8143 and Tie 6915 was separately controlled by one single dominant gene. The two dominant genes were identified to be linked on the MLG F by Mendel＇s genetics and SSR genetic mapping. The order and distance of markers DPRSMV1 and DSRSMV1 were Sat 229-6.9 cM-DSRSMV1-4.6 cM-Sat_317-3.6 cM-DPRSMV1-5.2 cM-Satt335. The order and distance of markers TPRSMV1 and TSRSMV1 was Satt160-16.1 cM-TPRSMV1-7.3 cM-Satt516-2.0 cM-TSRSMV1-4.5 cM-Sat_133. This research provides the useful information for breeders to select the two types of SMV resistance simultaneously in soybean breeding through molecular marker-assisted selection （MAS）.

关键词： soybean SMV seed coat mottling genetic analysis SSR gene mapping

Development of a DFN-based probabilistic block theory approach for bench face angle design in open pit mining

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3047-3062页

作者： Jianhua yan Xiansen Xing Zhihai Li Weida Ni Liuyuan Zhao chun zhu Yuanyuan He School of Earth Sciences and Engineering Hohai UniversityNanjing210098China POWERCHINA Huadong Engineering Corporation Limited Hangzhou311122China Zhejiang Huadong Construction Corporation Limited Hangzhou310004China The Seventh Geological Brigade of Hubei Geological Bureau Yichang443000China

In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation *** this reason,bench face angle,as one of the controlling parameters associated with block instabilities,should be carefully designed for sustainable *** study introduces a discrete fracture network(DFN)-based probabilistic block theory approach for the fast design of the bench face angle.A major advantage is the explicit incorporation of discontinuity size and spatial distribution in the procedure of key blocks *** proposed approach was applied to a granite mine in ***,DFN models were generated from a multi-step modeling procedure to simulate the complex structural characteristics of pit ***,a modified key blocks searching method was applied to the slope faces modeled,and a cumulative probability of failure was obtained for each ***,a bench face angle was determined commensurate with an acceptable risk level of *** simulation results have shown that the number of hazardous traces exposed on the slope face can be significantly reduced when the suggested bench face angle is adopted,indicating an extremely low risk of uncontrolled block instabilities.

关键词： Open pit mine Bench face angle Block theory Probabilistic approach Discrete fracture network modeling Fractured rock slope

Direct conversion of CO and H_(2)O to hydrocarbons at atmospheric pressure using a TiO_(2-x)/Ni photothermal catalyst

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Science China Materials 2024年第3期67卷 1009-1010页

作者： yan zhu School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210093China

Generating high-value chemical compounds by catalytically converting carbon resources—typically derived from coal and biomass, etc.—is crucial. It is more meaningful to achieve“carbon neutrality” and lower production costs by utilizing industrial waste carbon sources, such as steel mill waste gases,which are typically intended for direct emission or burning into CO_(2).

关键词： typically utilizing meaningful