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Lightweight Design and Verification of Gantry machining Center Crossbeam Based on Structural Bionics

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Journal of Bionic Engineering 2011年第2期8卷 201-206页

作者： ling Zhao Jianfeng ma Wuyi Chen Hongliang Guo School of Automobile and Transportation Engineering Liaocheng University Liaocheng 252059 P. R. China School of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology Beijing 100124 P. R. China School of Mechanical Engineering and Automation Beihang University Beijing 100191 P. R. China

The lightweight and high efficiency of natural structures are the inexhaustible sources for engineering improvements. The goal of the study is to find innovative solutions for mechanical lightweight design through the application of structural bionic approaches. Giant waterlily leaf ribs and cactus stem are investigated for their optimal framework and superior performance. Their structural characteristics are extracted and used in the bio-inspired design of Lin MC6000 gantry machining center crossbeam. By mimicking analogous network structure, the bionic model is established, which has better load-carrying capacity than conventional distribution. Finite Element Method （FEM） is used for numerical simulation. Results show better specific stiffness of the bionic model, which is increased by 17.36%. Finally the scaled models are fabricated by precision casting for static and dynamic tests. The physical experiments are compared to numerical simulation. The results show that the maximum static deformation of the bionic model is reduced by about 16.22%, with 3.31% weight reduction. In addition, the first four natural frequencies are improved obviously. The structural bionic design is a valuable reference for updating conventional mechanical structures with better performance and less material consumption.

关键词： lightweight design crossbeam structural bionics finite element method giant waterlily leaf

Restorable variation of cytoplasmic type of male sterile line in rice by in vitro culture

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Chinese Science Bulletin 2000年第24期45卷 2246-2250页

作者： Dinghou ling Zhenrong ma Chinese Acad Sci S China Inst Bot Guangzhou 510650 Peoples R China

Rice male sterile (MS) lines, IR66707A and IR69700A, which possess the cytoplasm of Oryza perennis and O. glumaepatula respectively, belong to the cytoplasmic type. Their sterility could be maintained but not be restored. By somatic cell culture of these two MS lines, 47 somaclones with 465 R1 plants were obtained. All of the 465 R1 plants were sterile in the spring season in Guangzhou. According to the expression of the R1 plants and the level of similarity to their donor parents, they could be divided into three types. The plants of type I were male sterile. The sterility of some somaclones of this type could be restored by the test crossing varieties or alternated to fertile by changes of some environmental conditions. The hybrid F1 of test cross from the MS somaclones in type I was fertile while the hybrid F1 from the donor MS lines was still sterile. The R1 plants of type Ⅱ were similar to the donor parents and also male sterile. The hybrid F1 from all of the plants of type Ⅱ crossed to test

关键词： somaclonal variation cytoplasm-type of MS restorable variation of male sterile rice.

Crystalline,Rheological and Mechanical Enhancement in PBAT/PPC/Silica Nanocomposites with Double Percolation Network

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Chinese Journal of Polymer Science 2022年第11期40卷 1482-1492页

作者： You-Mei ma Feng-Xiang Gao Shu-ling Zhang College of Chemistry Jilin UniversityChangchun130012China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China

Nanocomposites of blends of biodegradable poly(butylene adipate-co-terephthalate)(PBAT)and sustainable poly(propylene carbonate)(PPC)with nanosilica were prepared by melt compounding ***/PPC blend was partially miscible system with sea-island structure,and nanosilica particles were selectively dispersed in the continuous phase PBAT matrix to form the double percolation *** introduction of nanosilica into PBAT/PPC blend reduced the size of dispersed PPC phase,promoted the crystallization of PBAT in the nanocomposites,and increased the storage modulus of the *** study of rheological behaviors indicated that the double percolation network was formed at the nanosilica loading of 5 wt%,as a result,the nanocomposites exhibited the solid-like viscoelastic behavior and their relaxation time was *** the increase of the nanosilica content,the PBAT/PPC/silica nanocomposites displayed increased Young's modulus and yield strength.

关键词： Nanocomposites Selective dispersion Double percolation Enhanced properties

Sodium 4-phenylbutyrate Attenuates High-fat Diet-induced Impaired Spermatogenesis

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Biomedical and Environmental Sciences 2018年第12期31卷 876-882页

作者： WANG Er Hui YAO San qiao TAO ling XI Jin Yan Department of Nutrition and Food Hygiene College of Public Health Xinxiang Medical University Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine Xinxiang Medical University

Objective To determine the mitigating effects of sodium 4-phenylbutyrate(4-PBA) on high-fat diet(HFD)-induced spermatogenesis dysfunction. Methods male rats(n = 30) were randomly divided into three groups: control, HFD, and 4-PBA(HFD +4-PBA). After 13 weeks, rats were euthanized. Testes and epididymis were harvested for further analysis. Sex hormones were detected, and hematoxylin and eosin staining was performed to examine the histological changes in the testes. Semen samples were collected to evaluate sperm quality. Spermatogenic cell apoptosis was detected by TUNEL assay. Results Compared with the control group, the final body weight and body weight gain were significantly higher in HFD-fed rats, while the testicle/body weight ratios were lower(P mage, ameliorated the HFD-induced decrease in serum testosterone(T), and reduced the rate of testicular cell apoptosis(P male rats. Finally, 4-PBA significantly improved semen parameters in HFD rats(P matogenesis, semen quality, serum T level, and testicular cell apoptosis in rats. Treatment with 4-PBA ameliorated HFD-induced impaired spermatogenesis via inhibition of apoptosis in rats. 4-PBA may have therapeutic value in the treatment of obesity-related impairment of spermatogenesis.

关键词： male infertility Sodium 4-phenylbutyrate Obesity Spermatogenesis Semen Testis

Flexible Robotic Grasping Strategy with Constrained Region in Environment

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International Journal of Automation and computing 2017年第5期14卷 552-563页

作者： Chao ma Hong qiao Rui Li Xiao-Qing Li School of Automation and Electrical Engineering University of Science and Technology Beijing State Key Laboratory of management and Control for Complex Systems Institute of AutomationChinese Academy of Sciences

Grasping is a significant yet challenging task for the robots. In this paper, the grasping problem for a class of dexterous robotic hands is investigated based on the novel concept of constrained region in environment, which is inspired by the grasping operations of the human beings. More precisely, constrained region in environment is formed by the environment, which integrates a bio-inspired co-sensing framework. By utilizing the concept of constrained region in environment, the grasping by robots can be effectively accomplished with relatively low-precision sensors. For the grasping of dexterous robotic hands, the attractive region in environment is first established by model primitives in the configuration space to generate offline grasping planning. Then, online dynamic adjustment is implemented by integrating the visual sensory and force sensory information, such that the uncertainty can be further eliminated and certain compliance can be obtained. In the end, an experimental example of BarrettHand is provided to show the effectiveness of our proposed grasping strategy based on constrained region in environment.

关键词： Grasping strategy compliant grasping dexterous robotic hands attractive region in environment constrained region inenvironment.

Present and future of hydrology

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Water Science and Engineering 2013年第3期6卷 241-249页

作者： Xiao-fang RUI Ning-ning LIU qiao-ling LI Xiao LIANG College of Hydrology and Water Resources Hohai University

The complexities of hydrological phenomena, the causes that lead to these complexities, and the essences and defects of reductionism are analyzed. The driving forces for the development of hydrology and the formation of branch subjects of hydrology are discussed. The theoretical basis and limitations of existing hydrology are summarized. Existing misunderstandings in the development of the watershed hydrological model are put forward. Finally, the necessity of the expansion of hydrology from linear to nonlinear is discussed.

关键词： hydrological phenomenon hydrological theory hydrological method hydrologicalmodel reductionism nonlinear

A New Phosphine-Amine-Oxazoline Ligand for Ru-Catalyzed Asymmetric Hydrogenation of N-Phosphinylimines

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Chinese Journal of Chemistry 2018年第12期36卷 1151-1155页

作者： Xiaochen ma Lin qiao Guixia Liu Zheng Huang State Key laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RdShanghai 200032China

A series of chiral phosphine‐amine‐oxazoline (PAO) ligands with an NH moiety were synthesized and applied to the ruthenium‐catalyzed asymmetric hydrogenation of N ‐phosphinylimines. The ligand bearing phenyl groups at the phosphorus moiety and isopropyl at the oxazoline moiety exhibits good activity and excellent enantioselectivity (up to 99% ee ). This catalytic system provides an efficient and mild approach to access enantioriched amines.

关键词： amines chiral ligand hydrogenation imines ruthenium

Polymorphisms in genes involved in folate metabolism as maternal risk factors for Down syndrome in China

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第2期9卷 93-99页

作者： Shao-shuai WANG Fu-yuan qiao ling FENG Juan-juan LV Department of Obstetrics and Gynecology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

Objective: To explore the relationship between genetic polymorphisms in methylenetetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR), the central enzymes in folate metabolism that affects DNA methylation and synthesis, and the risk of Down syndrome in China. Methods: Genomic DNA was isolated from the peripheral lymphocytes of 64 mothers of children with Down syndrome and 70 age matched control subjects. Polymerase chain reaction and restriction fragment length polymorphism were used to examine the polymorphisms of MTHFR 677C→T, MTRR 66A→G and the relationship between these genotypes and the risk of Down syndrome was analyzed. Results: The results show that the MTHFR 677C→T polymorphism is more prevalent among mothers of children with Down syndrome than among control mothers, with an odds ratio of 3.78 (95% confidence interval (CI), 1.78～8.47). In addition, the homozygous MTRR 66A→G polymorphism was independently associated with a 5.2-fold increase in estimated risk (95% CI, 1.90～14.22). The combined presence of both polymorphisms was associated with a greater risk of Down syndrome than the presence of either alone, with an odds ratio of 6.0 (95% CI, 2.058～17.496). The two polymorphisms appear to act without a multiplicative interaction. Conclusion: MTHFR and MTRR gene mutation alleles are related to Down syndrome, and CT, TT and GG gene mutation types increase the risk of Down syndrome.

关键词： Tetrahydrofllate dehydrogenase Ligases Down syndrome Folate

A facile approach to construct hybrid multi-shell calcium phosphate gene particles

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第4期11卷 292-297页

作者： Zhi-xue XU Ran ZHANG You-xiang WANG qiao-ling HU MOE Key Laboratory of macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 31002 7 China

The calcium phosphate (CaP) particles have attracted much attention in gene therapy. How to construct stable gene particles was the determining factor. In this study,hybrid multi-shell CaP gene particles were successfully constructed. First,CaP nanoparticles served as a core and were coated with DNA for colloidal stabilization. The ξ-potential of DNA-coated CaP nanoparticles was -15 mV. Then polyethylenimine (PEI) was added and adsorbed outside of the DNA layer due to the electrostatic attraction. The ξ-potential of hybrid multi-shell CaP particles was slightly positive. With addition of PEI,the hybrid multi-shell particles could condense DNA effectively,which was de-termined by ethidium bromide (EtBr) exclusion assay. The hybrid particles were spherical and uniform with diameters of about 150 nm at proper conditions. By simple modification of PEI,the hybrid multi-shell CaP gene particles were successfully constructed. They may have great potential in gene therapy.

关键词： Calcium phosphate Polyethylenimine (PEI) Hybrid Gene