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POLYMER NETWORK-POLY(ETHYLENE GLYCOL)COMPLEXES WITH SHAPE MEMORY EFFECT

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Chinese Journal of Polymer Science 2003年第1期21卷 29-33页

作者： Yi-ping cao C.W.Yip 等 InstituteofOrganicChemistry ChineseAcademyofSciencesChengdu610041China DepartmentofAppliedBiologyandChemicalTechnology hongKongPolytechnicUniversityHungHomkowloonHongKongChina

The complexes of poly(methacrylic acid-co-methyl methacrylate) network with poly(ethylene glycol) stabilized byhydrogen bonds were prepared. By introducing the poly(ethylene glycol), a large difference in storage modulus below andabove the glass transition temperature occurred and the complexes exhibited shape memory behaviors. The morphology ofcomplexes was studied by using DSC, WAXD, and DMA. The results indicate that the fixed phase of this kind of novelshape memory materials is the network, and the reversible phase is the amorphous state of PEG:PMAA complex phase. Theshape recoverability almost reaches 100%. This type of complexes can be regarded as a novel shape memory network.

关键词： Hydrogen bonded complex Shape memory effect Storage modulus ratio

Classification of microseismic events in high stress zone

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Mining Science and Technology 2009年第6期19卷 718-723页

作者： cao An-ye DOU Lin-ming YAN Ru-ling JIANG Heng lu Cai-ping DU Tao-tao lu Zhen-yu State Key Laboratory for Coal Resource and Mine Safety China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China School of Mines China University of Mining ＆ Technology Xuzhou Jiangsu 221006 China

For the purpose of having a better understanding of failure mechanisms of rock fracturing in mines, the equivalent point source models of tensile, shear and explosive seismic events were established, and the relationship between far-field seismic displacements of the waves and the corresponding equivalent forces were analyzed as well. Based on the results of a microseismic monitoring carried out in the mining progress of 9202 working face under the upper remnant coal pillar in Sanhejian Mine, the waveform features of the seismic events associated with different failure modes were further analyzed. The results show that the signals corresponding to different failure mechanisms have different radiation patterns of the seismic displacements, and different characteristics in waveform features, such as dominant frequency, energy released, the ratio of S- to P-wave energy, and so on. In addition, the rock burst happened in the high stress zone is mainly the result of the strong shear fracturing in the mining process. The results of this study have significantly improved the understanding of the characteristics of the failures associated with underground mining, and will greatly benefit the prevention and control of rock burst hazards in burst-prone mines.

关键词： rock burst microseismic monitoring failure mechanism waveform characteristics

Sustainable routes for quantitative green selenocyanation of activated alkynes

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Chinese Chemical Letters 2019年第6期30卷 1237-1240页

作者： Ling-Hui lu Zheng Wang Weng Xia ping Cheng Bo Zhang Zhong cao Wei-Min He Department of Chemistry Hunan University Changsha 410082 China Department of Chemistry Hunan University of Science and Engineering Yongzhou 425100 China School of Chemistry and Chemical Engineering Hunan University of Science and Technology Xiangtan 411201 China Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation Changsha University of Science and Technology Changsha 410114 China

Most organic reactions require the usage of volatile organic compounds in the synthesis, work-up and purification processes, thus resulting in major environmental pollution and high manufacturing cost. By using cheap biomass lactic acid as the reaction media and catalyst, a sustainable protocol for the synthesis of Z-3-selenocyanatoacrylates and analogues through green selenocyanation of activated alkynes has been achieved. A principal advantage of this protocol is that the usage of organic volatile compounds can be avoided entirely, as the conversion of substrate is almost quantitative or quantitative with a minimal amount of lactic acid employed as reaction media, and the pure products can be conveniently collected through water precipitation.

关键词： Green chemistry Organic volatile compounds Biomass Alkynes Potassium selenocyanate

Observer-based adaptive consensus control for nonlinear multi-agent systems with time-delay

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Science China(Information Sciences) 2020年第3期63卷 195-211页

作者： Wenbin XIAO Liang cao Hongyi LI Renquan lu School of Automation and Guangdong Province Key Laboratory of Intelligent Decision and Cooperative Control Guangdong University of Technology

In this paper, we consider the observer-based adaptive consensus tracking problem for a class of nonlinear time-delay multi-agent systems in the presence of input saturation. Under the assumption that the communication topology is directed and connected, a distributed adaptive consensus controller is developed based on the dynamic surface control technique. By constructing the nonlinear observer, the unmeasurable agents dynamics can be estimated. Input saturation problem is solved by a smooth function combined with an auxiliary variable. With the help of prescribed performance functions, the synchronization errors converge to the prescribed sets, which are characterized as a neighborhood of zero. According to Lyapunov stability theory, it is shown that with the proposed distributed consensus tracking approach, the consensus errors are cooperatively semi-globally uniformly ultimately bounded. Finally, a simulation example is provided to show the effectiveness of the proposed algorithm.

关键词： adaptive consensus control multi-agent systems prescribed performance time-delay unmeasurable states

Differential Responses of the Activities of Antioxidant Enzymes to Thermal Stresses between Two Invasive Eupatorium Species in China

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Journal of Integrative Plant Biology 2008年第4期50卷 393-401页

作者： ping lu Wei-Guo Sang Ke-ping Ma Key Laboratory of Vegetation and Environment Change Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Resources and Environmental Sciences College Northeast Agricuitural University Harbin 150030 China

The effect of thermal stress on the antioxidant system was investigated in two invasive plants, Eupatorium adenophorum Spreng. and E. odoratum L. The former is sensitive to high temperature, whereas the latter is sensitive to low temperature. Our aim was to explore the relationship between the response of antioxidant enzymes and temperature in the two invasive weeds with different distribution patterns in China. Plants were transferred from glasshouse to growth chambers at a constant 25 ℃for I week to acclimatize to the environment. For the heat treatments, temperature was increased stepwise to 30, 35, 38 and finally to 42 ℃. For the cold treatments, temperature was decreased stepwise to 20, 15, 10 and finally to 5 ℃. Plants were kept in the growth chambers for 24 h at each temperature step. In E. adenophorum, the coordinated increase of the activities of antioxidant enzymes was effective in protecting the plant from the accumulation of active oxygen species （AOS） at low temperature, but the activities of catalase （CAT）, guaiacol peroxidase （POD）, ascorbate peroxidase （APX）, glutathione reductase （GR）, and monodehydroascorbate reductase （MDAR） were not accompanied by the increase of superoxide dismutase （SOD） during the heat treatments. As a result, the level of lipid peroxidation in E. adenophorum was higher under heat stress than under cold stress. In E. odoratum, however, the lesser degree of membrane damage, as indicated by low monodehydroascorbate content, and the coordinated increase of the oxygen. Datoxifying enzymes were observed in heat-treated plants, but the antioxidant enzymes were unable to operate in cold stress. This indicates that the plants have a higher capacity for scavenging oxygen radicals in heat stress than in cold stress. The different responses of antioxidant enzymes may be one of the possible mechanisms of the differences in temperature sensitivities of the two plant species.

关键词： antioxidant enzyme system cold stress Eupatorium adenophorum Eupatorium odoratum heat stress invasive plants.

Self-assembled all-oxides three-phase vertically aligned nanocomposite thin film with multifunctionality

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Nano Research 2024年第9期17卷 8226-8232页

作者： Jijie Huang Yuan Fang ping lu Juanjuan lu Haiyan Wang School of Materials Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China School of Materials Engineering Purdue UniversityWest LafayetteIN 47907USA Sandia National Laboratories AlbuquerqueNew Mexico 87185USA School of Electrical and Computer Engineering Purdue UniversityWest LafayetteIN 47907USA

Multi-phase vertically aligned nanocomposite(MP-VAN)thin films represent a promising avenue for achieving complex multifunctionality,exploring novel interfacial phenomena,and enabling complex metamaterial designs and *** this study,a novel self-assembled all-oxides three-phase VAN system was conceptualized and fabricated utilizing pulsed laser deposition(PLD)with a single composite *** microstructural analysis reveals the presence of three distinct phases:LiNbO_(3),CeO_(2-x),and LiNbCe_(1-x)O_(y)within the MP-VAN ***,ferroelectric,dielectric,optical anisotropy,and magnetic properties were systematically investigated to showcase the multifunctionality inherent in these *** work presents a pioneering approach to designing and realizing MP-VAN systems,and opens up opportunities for tailoring the complex three-dimensional(3D)physical properties and property coupling of VAN films towards diverse device applications.

关键词： thin film three-phase vertically aligned nanocomposite multifunctionality ferroelectricity optical anisotropy

A novel mutation in FBN1 gene in autosomal dominant Marfan syndrome and macular degeneration in a Chinese consanguineous family

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International Journal of Ophthalmology(English edition) 2019年第5期12卷 725-730页

作者： ping-Bo Ouyang Yuan Zhao Ying-Qian Peng lu-Si Zhang Jian cao Yun Li Department of Ophthalmology the Second Xiangya Hospital of Central South University Hunan Clinical Research Center of Ophthalmic Disease Department of Cardiovascular Surgery the Second Xiangya Hospital of Central South University

AIM: To report a novel mutation in FBN1 gene in a Chinese consanguineous family with common Marfan syndrome(MFS) phenotype and an unusual bilateral macular degeneration. METHODS: Ophthalmic, cardiovascular and systemic examinations were performed, and genomic DNA extracted from all living family members. The 24-32 exon mutations of FBN1 gene were screened by Sanger Sequencing in all family members and 100 unrelated healthy Chinese individuals. RESULTS: In the four-generation family, classic MFS phenotypes were observed in all 5 patients, 2 of them had peculiar phenotype of bilateral macular degeneration. Mutation screening in FBN1 identified a heterozygous missense mutation(c.3932 A>G, p.Y1311 C) with co-segregation. This mutation was found with the MFS phenotypes in all 5 patients but not in unaffected members or unrelated controls. CONCluSION: A Chinese consanguineous MFS family with uncommon bilateral macular degeneration and an unreported c.3932 A>G mutation in FBN1 was identified. Our finding expands the FBN1 mutation spectrum and its possible role in the pathogenesis of Marfan syndrome.

关键词： Marfan syndrome fibrillin-1 autosomal dominant heterozygous mutation

How should congenital absence of cruciate ligaments be treated? A case report and literature review

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World Journal of Clinical Cases 2019年第19期7卷 3082-3089页

作者： Ran lu Dong-ping Zhu Neng Chen He Sun Ze-Hui Li Xue-Wei cao Department of Orthopedics Guangdong Provincial Hospital of Traditional Chinese Medicine

BACKGROUND Hypoplasia of bilateral cruciate ligaments is a rare congenital *** diagnosis of such diseases and indications for the various treatment options require further analysis and *** SUMMARY The patient is a 26-year-old Chinese woman who has been suffering from knee pain since the age of 8 years,2-3 episodes a *** years ago,due to the practice of advanced yoga poses,the frequency of left knee pain increased,requiring prompt medical *** resonance imaging demonstrated an absence of both anterior and posterior cruciate ligaments of both knees with abnormal posterior tilting of the tibial *** subluxation of the knee joint was also found,therefore tibial osteotomy was *** patient reported at the 24 mo follow-up that the frequency of pain and instability had been reduced and function *** Osteotomy may be an effective method to treat patients with congenital cruciate ligament deficiency with posterior tibial plateau *** diagnosis of congenital cruciate ligament deficiency shall be based on the combination of patient’s medical history,clinical manifestations,and findings from imaging to avoid possible *** on the symptoms,frequency of attacks,and intent of the individual,appropriate treatment options shall be identified.

关键词： Congenital Dysplasia Cruciate ligament Congenital deformity Osteotomy Case report

Semi-solid Thixoforming Simulation of Al-Cu-Mn-Ti Alloy Parts via AnyCasting

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Journal of Materials Science & Technology 2007年第3期23卷 359-362页

作者： ping WANG Jianzhong CUI Guimin lu Key Laboratory of Ministry of Education for Electromagnetic Processing of Materials Northeastern University Shenyang 110004 China

The software AnyCasting was used to simulate the thixotropic die-casting process of semi-solid Al-Cu-Mn-Ti alloy slurry to form the parts of a particular shape, especially on how the in-gate size of die and injection speed affect the process. The results showed that the die cavity can be filled well with the semi-solid slurry in form of laminar flow under conditions that the temperature of the semi-solid slurry is 640℃ and that of die 200-240℃, thickness of in-gate is 11 mm and, more important, the injection speed should be changed from 0.1 to 1.0 m/s when 60% of die cavity has been filled. The simulation result is highly proved in conformity to the actual die-casting specimens in accordance to the filling process as simulated. Moreover, the hardness of the specimens is up to 116.6 HV after the treatment of solid solution plus underaging, i.e. 45.7% higher than that in conventional ones.

关键词： Al-Cu-Mn-Ti alloy Seml-solid die casting Laminar flow Hardness