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Studies on Mechanical Properties of Full-Biodegradable Starch-PVA-Polyester Films

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Chemical Research in Chinese Universities 2003年第1期19卷 107-111页

作者： RAN xiang-hai GAO Ge 等 ChangchunInstituteofAppliedChemistry ChineseAcademyofSciencesChangchun130022P.R.China CollegeofChemistry JilinUniversityChangchun130023P.R.China

A kind of full biodegradable film material is discussed in this article. The film material is composed of starch, PVA, degradable polyesters(PHB, PHB V, PCL) with built plasticizer, a cross linking reinforcing agent and a wet strengthening agent. It contains a high percentage of starch, costs cheap and is excellent in weather fastness, temperature resistance and waterproof and it could be completely biodegraded. The present paper deals mainly with a new technical route using a new type of electromagnetic dynamic blow molding extruder and some effects on mechanical properties of the system.

关键词： Starch PVA Degradable polyester Full biodegradable Mechanical properties

INVESTIGATION ON SOUND ABSORPTION PROPERTIES OF KAPOK FIBERS

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Chinese Journal of Polymer Science 2013年第3期31卷 521-529页

作者： hai-fan xiang Dong Wang Hui-chao Liu 赵宁徐坚 Beijing National Laboratory for Molecular Sciences Laboratory of Polymer Physics and ChemistryInstitute of ChemistryChinese Academy of Sciences Graduate University of the Chinese Academy of Sciences

Sound absorption properties of natural kapok fibers have been investigated. Kapok fibrous assemblies with different bulk density, thickness, fiber length and orientation were manufactured, and their acoustical performances were evaluated by using an impedance tube instrument. Results show that the kapok fiber has excellent acoustical damping performance due to its natural hollow structure, and the sound absorption coefficients of kapok fibrous assemblies are significantly affected by the bulk density, thickness and arrangement of kapok fibers but less dependent on the fiber length. Compared with assemblies of commercial glass wool and degreasing cotton fibers, the kapok fiber assemblies with the same thickness but much smaller bulk density may have the similar sound absorption coefficients. Theoretical modelling of the acoustical damping performance of kapok fibers shows a good agreement with the experimental data. All the results demonstrate that kapok fiber is a promising light and environment-friendly sound absorption material.

关键词： Kapok fiber Hollow structure Sound absorption coefficient Bulk density.

Flow field fusion simulation method based on model features and its application in CRDM

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Nuclear Science and Techniques 2022年第3期33卷 89-102页

作者： Si-Tong Ling Wen-Qiang Li Chuan-Xiao Li hai xiang School of Mechanical Engineering Sichuan UniversityChengdu 610065China Innovation Method and Creative Design Key Laboratory of Sichuan Province Chengdu 610065China

The control rod drive mechanism(CRDM)is an essential part of the control and safety protection system of pressurized water *** CRDM simulations are mostly performed collectively using a single method,ignoring the influence of multiple motion units and the differences in various features among them,which strongly affect the efficiency and accuracy of the *** this study,we constructed a flow field fusion simulation method based on model features by combining key motion unit analysis and various simulation methods and then applied the method to the CRDM simulation *** performs motion unit decomposition through the structural hierarchy of function-movement-action method,and the key meta-actions are identified as the nodes in the flow field *** established a fused feature-based multimethod simulation process and processed the simulation methods and data according to the features of the fluid domain space and the structural complexity to obtain the fusion simulation *** to traditional simulation methods and real measurements,the simulation method provides advantages in terms of simulation efficiency and accuracy.

关键词： CRDM Flow field simulation Motion unit analysis Simulation method fusion

Riboflavin/ultraviolet A-induced collagen cross-linking in rabbit corneal scar

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International Journal of Ophthalmology(English edition) 2019年第1期12卷 46-50页

作者： You-Huan Cai Tai-xiang Liu hai-xiang Li Guizhou Ophthalmic Hospital the Affiliated Hospital of Zunyi Medical College

AIM: To evaluate the biomechanical stability of the corneal scar treating with riboflavin and ultraviolet A(UVA). METHODS: Totally 86 New Zeal rabbits were divided into control group(group A, n=8) and trauma groups [group B(n=27), group C(n=24) and group D(n=27)]. Then groups B, C and D were divided into three sub-groups according to the time points of sacrifice, i.e. groups Ba, Ca and Da(4 wk, n=8); Bb, Cb and Db(6 wk, n=8); Bc(n=11), Cc(n=8) and Dc(8 wk, n=11). The right corneas of these 78 rabbits in the trauma groups were penetrated. Group B were only sutured. Group C were treated with corneal cross-linking(CXL) immediately after suturing. Group D were treated with CXL seven days after suturing. The corneal scar strips of 4.0×10.0 mm2 were cut and the stress and Young's modulus at 10% strain were evaluated. Samples from the three rabbits of group Bc and three of group Dc were used to measure the expression of alpha smooth muscle action(α-SMA). RESULTS: The mechanical strength of the corneal scar increased with time, and was strongest at 8 wk after the injury. The ultimate stress of corneal scar(group D) were 2.17±0.52 MPa, 2.92±0.63 MPa, and 4.21±0.68 Mpa at 4 wk, 6 wk and 8 wk, respectively; Young's modulus were 10.94±1.57 MPa, 11.16±2.50 MPa, and 13.36±2.10 Mpa, which were higher than that of other groups except for normal control. The expression of α-SMA in group B and group D were 0.28±0.11 and 0.65±0.20, respectively, and the difference was statistically significant(P=0.048). CONCLUSION: CXL with riboflavin/UVA at seven days after suturing improved the biomechanical properties of corneal scars most effectively in the present study.

关键词： crosslinking cornea biomechanics corneal penetrating injury rabbit

Analysis of Crack Tip Stress of Transversal Crack on Slab Corner During Vertical-Horizontal Rolling Process by FEM

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Journal of Iron and Steel Research International 2008年第3期15卷 19-26页

作者： YU hai-liang LIU xiang-hua WANG Guo-dong The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Behavior of transversal crack notched on slab corner during vertical-horizontal rolling process was simulated by FEM. The crack tip stress in the whole rolling process was obtained. Influences of the friction coefficient, the initial crack size, the edger roll profile, and the groove fillet radii of grooved edger roll on crack tip stress were analyzed. For vertical rolling, the tension stress appears at crack tip near the slab top surface and the compression stress appears at crack tip near the slab side surface for the flat edger roll; however, the compression stress appears at crack tip near the slab top surface and the tension stress appears at crack tip near the slab side surface in the exit stage for the grooved edger roll. For horizontal rolling, the tension stress appears at crack tip just at the exit stage for the flat edger roll, and the tension stress appears in whole rolling stage; the tension stress value near the slab side surface is much larger than that near the slab top surface for the grooved edger roll.

关键词： transversal crack vertical-horizontal rolling process crack tip stress FEM

Microstructure and Mechanical Properties of Hot-Rolled Fe-Mn-C-Si TWIP Steel

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Journal of Iron and Steel Research International 2011年第12期18卷 45-48,64页

作者： ZHANG Li LIU xiang-hai SHU Kang-ying Hangzhou Aichi Engineering Vehicles Co Ltd Hangzhou 310018 Zhejiang China Department of Materials Seience and Engineering China Jiliang University Hangzhou 310018 Zhejiang China

Mechanical properties and microstructural evolution of the hot-rolled Fe-Mn-C-Si TWIP steel were investigated and the deformation mechanism was *** results showed that the tensile strength and elongation were about 1050 MPa and 60%,*** hot-rolled steel had high specific energy absorption and impact toughness between-120 ℃ and 20 ℃.Some inhomogeneous dislocation zones were observed in the undeformed *** of deformation twins and twin-dislocation interactions were observed in the deformed *** effect was the major deformation mechanism for the excellent mechanical properties.

关键词： TWIP steel hot-rolling microstructure mechanical property deformation twin

Fabrication and luminescent properties of Eu(BMPPA)3BPy complex and its functionalized silica nanocomposites

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Chinese Chemical Letters 2016年第10期27卷 1602-1606页

作者： Hong-xiang Huang Wen-Li He xiang-hai Sheng wen-Jie wu Department of Macromolecular Science and State Key Laboratory of Molecular Engineering of Polymers Shanghai 200433China Department of Chemistry Fudan UniversityShanghai 200423China

Luminescent silica nanocomposites functionalized with a Eu-complex have been prepared and characterized. The europium complex is composed of 2,2＇-bipyridyl （BPy） and 2-（4-bromomethyl）- phenylpropionic acid （BMPPA）, which contains highly active benzyl bromide substituents and can covalently bind with poly（4-vinylpyridine）（P4VP）-modified silica nanoparticles （nanoSiO2P4VP） to form nanoSiO2P4VPEuBIy composites. Microscopic images revealed that the nanoSiO2P4VPEuBPy composites easily formed aggregates, due to an inter-particle binding caused by the benzyl bromide among the composites. The as-prepared nanocomposites showed the typical emissions of Eu（III） ions at the wavelengths from 580 nm to 750 nm designated to the SDo- 7Fn transitions. Time-resolved fluorescence decay measurements revealed that the emission lifetime was approximately 0.204 ms and 0.5？6 ms for the nanoSiO2EuBPy composites, a little shorter than that in the Eu（BMPPA）3BPy complex.

关键词： Eu-complexNanocompositesSilica nanoparticlesFluorescence

Ensemble Bayesian method for parameter distribution inference:application to reactor physics

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Nuclear Science and Techniques 2023年第12期34卷 216-228页

作者： Jia‑Qin Zeng hai‑xiang Zhang He‑Lin Gong Ying‑Ting Luo School of Mathematics Sichuan UniversityChengdu 610065China Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China

The estimation of model parameters is an important subject in *** this area of work,the prevailing approach is to estimate or calculate these as deterministic *** this study,we consider the model parameters from the perspective of random variables and describe the general form of the parameter distribution inference *** this framework,we propose an ensemble Bayesian method by introducing Bayesian inference and the Markov chain Monte Carlo(MCMC)*** on a finite cylindrical reactor and a 2D IAEA benchmark problem show that the proposed method converges quickly and can estimate parameters effectively,even for several correlated parameters *** experiments include cases of engineering software calls,demonstrating that the method can be applied to engineering,such as nuclear reactor engineering.

关键词： Model parameters Bayesian inference Frequency distribution Ensemble Bayesian method KL divergence

The phylogenetic status of typical Chinese native pigs: analyzed by Asian and European pig mitochondrial genome sequences

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Journal of Animal Science and Biotechnology 2013年第2期2013卷 145-151页

作者： Guanghui Yu hai xiang Jikun Wang Xingbo Zhao National Engineering Laboratory for Animal Breeding Ministry of Agricultural Key Laboratory of Animal Genetics Breeding and Reproduction State Key Laboratory for Agribiotechnology College of Animal Science and Technology China Agricultural University

China is one of the most diverse countries, which have developed 88 indigenous pig breeds. Several studies showed that pigs were independently domesticated in multiple regions of the world. The purpose of this study was to investigate the origin and evolution of Chinese pigs using complete mitochondrial genomic sequences (mtDNA) from Asian and European domestic pigs and wild boars. Thirty primer pairs were designed to determine the mtDNA sequences of xiang pig, Large White, Lantang, Jinhua and Pietrain. The phylogenetic status of Chinese native pigs was investigated by comparing the mtDNA sequences of complete coding regions and D-loop regions respectively amongst Asian breeds, European breeds and wild boars. The analyzed results by two cluster methods contributed to the same conclusion that all pigs were classified into two major groups, European clade and Asian clade. It revealed that Chinese pigs were only recently diverged from each other and distinctly different from European pigs. Berkshire was clustered with Asian pigs and Chinese pigs were involved in the development of Berkshire breeding. The Malaysian wild boar had distant genetic relationship with European and Asian pigs. Jinhua and Lanyu pigs had more nucleotide diversity with Chinese pigs although they all belonged to the Asian major clade. Chinese domestic pigs were clustered with wild boars in Yangtze River region and South China.

关键词： Mitochondrial DNA Origin and evolution Phylogenetic analysis Pig