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Mechanical, thermal and fire nanoclay/vinylester retardation behaviours of nanocomposites

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Frontiers of Materials science 2011年第4期5卷 401-411页

作者： K. R. VIsHNU MAHEsH H. N. NARAsIMHA murthy B. E. KUMARA sWAMY s. c. sHARMA R. sRIDHAR Niranjan PATTAR M. KRIsHNA B. s. sHERIGARA Department of P. G. studies and Research in Industrial chemistry Kuvempu University Shankaraghatta Shimoga 577451 Karnataka India Department of Mechanical Engineering R. V. College of Engineering Bangalore 560059 Karnataka India Tumkur University Tumkur 572103 Karnataka India

The dispersion of montmorillonite （MMT） in vinylester for preparing nanoclay/vinylester gel coat was reported. Two sets of MMT/vinylester specimens, namely Type I and Type 2, were prepared for comparative studies. Type I specimens were prepared using ultrasonication only, and Type 2 specimens were prepared using both ultrasonication and twin-screw extrusion. According to XRD and TEM results, Type 2 specimens showed lower levels of nanoclay agglomeration and higher levels o! exfoliation. Dsc results showed that the glass transition temperatures of Type 2 specimens are higher than those of Type 1 specimens. TGA results showed that the residual weight of 4 wt.% MMT/vinylester of Type 1 was 7.38%, while the corresponding value of Type 2 was 13,5%, indicating lower thermal degradation in the latter. MMTt vinylester/glass and MMT/vinylester/carbon specimens were fabricated and tested for mechanical and fire retardation behaviours. Type 2 based nanocomposite laminates showed greater values of ultimate tensile strength, flexural strength, interlaminar shear strength, impact strength, horizontal burning rate, and vertical burning rate than Type 1 based laminates. sEM images of tensile fractured surfaces revealed that Type 2 based laminates have no or less agglomeration of nanoclay than Type 1 based laminates.

关键词： twin-screw extrusion montmorillonite nanoclay nanocomposite vinylester

controversies in fecal incontinence

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World Journal of Gastroenterology 2025年第3期31卷 113-119页

作者： Andreia Albuquerque satish s.c.Rao school of Medicine and Biomedical sciences Fernando Pessoa UniversityGondomar 4420-096PortoPortugal Precancerous Lesions and Early cancer Management Research Group RIsE@cI-IPO(Health Research Network) Portuguese Oncology Institute of PortoPorto 4200-072Portugal Division of Gastroenterology and Hepatology Department of Internal MedicineAugusta UniversityAugustaGA 30912United States

Fecal incontinence is a common condition that can significantly impact patients’quality of *** anal sphincter injury and anorectal surgeries are common *** ultrasound and anorectal manometry are important diagnostic tools for evaluating *** are various treatment options,including diet,lifestyle modifications,drugs,biofeedback therapy,tibial and s.c.al nerve neuromodulation therapy,and *** this editorial,we will discuss.c.rrent controversies and novel approaches to fecal *** for asymptomatic anal sphincter defects after obstetric anal sphincter injury and in patients with inflammatory bowel disease is not generally recommended,but may be helpful in selected *** Garg incontinence score is a new score that includes the assessment of solid,liquid,flatus,mucous,stress and urge fecal *** tests s.c. as translumbos.c.al anorectal magnetic stimulation and novel therapies s.c. as translumbos.c.al neuromodulation therapy are promising diagnostic and treatment options,for both fecal incontinence and *** biofeedback therapy can overcome some limitations of the office-based *** muscle-derived cell implantation of the external anal sphincter has been further studied as a possible treatment *** neuromodulation may be useful in scleroderma,congenital fecal incontinence and inflammatory bowel disease but merits further study.

关键词： Fecal incontinence Endoanal ultrasound Anal sphincter defects Biofeedback Neuropathy s.c.al neuromodulation

Reduction of wave impact on seashore as well as seawall by floating structure and bottom topography

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Journal of Hydrodynamics 2020年第6期32卷 1191-1206页

作者： Amandeep Kaur s.c.Martha Department of Mathematics Indian Institute of Technology RoparRupnagarPunjabIndia

The three-dimensional problem involving diffraction of water wave by a finite floating rigid dock over an arbitrary bottom is studied for two cases(1)in the absence of wall(2)in the presence of *** problem is handled for its solution with the aid of step *** both asymmetric and symmetric arbitrary bottom profile is approximated using s.c.essive *** approximation helps to apply the matched eigenfunction expansion method,in result,system of algebraic equations are obtained which are solved to determine the hydrodynamic quantities,namely,force experienced by rigid floating dock as well as rigid seawall,free surface elevation,transmission and reflection coefficients ass.c.ated with transmission and reflected waves *** effects of various structural and system parameters are examined on these hydrodynamics *** appropriate values of length and thickness of dock,water depth and angle of incidence provide the salient information to marine and coastal engineers to design the offshore structures and creation of parabolic trench on the *** present results are compared with known results in special case of bottom *** energy balance relation is derived and checked.

关键词： Arbitrary bottom step approximation hydrodynamic quantities

An Inverse Approach for Extracting Elastic-plastic Properties of Thin Films from small scale sharp Indentation

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Journal of Materials science & Technology 2012年第7期28卷 626-635页

作者： Z.s. Ma Y.c. Zhou s.G. Long c.s. Lu Key Laboratory of Low Dimensional Materials ~ Application Technology of Ministry of Education Xiangtan Uni-versity Xiangtan 411105 China Faculty of Materials Optoelectronics and Physics Xiangtan University Xiangtan 411105 China Department of Mechanical Engineering Curtin University of Technology Perth WA 6845 Australia

An inverse method for extracting the elastic-plastic properties of metallic thin films from instrumented sharp indentation has been proposed in terms of dimensional analysis and finite element modeling. A wide range of materials with different elastic modulus, yield strength, and strain-hardening exponent were *** to the Nix-Gao model for the depth dependence of hardness H,the relationship between elastic modulus E and indentation depth h can be expressed as By combiningthese two formulas, we find that there is a relationship between yield stress and indentation depth h：where σyO is the yield strength ass.c.ated with the strain-hardening exponent n, the true hardness Ho and the true elastic modulus *** constant, whichis only related to n, and hH and hE are characteristic lengths for hardness and elastic modulus. The results obtained from inverse analysis show that the elastic-plastic properties of thin films.c.n be uniquely extracted from the solution of this relationship when the indentation size effect has to be taken into account.

关键词： Indentation Elastic-plastic properties Metal thin films Inverse analysis

Urban china in Transformation:Hybrid Economy,Juxtaposed space,and New Testing Ground for Geographical Enquiries

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chinese Geographical science 2011年第1期21卷 1-16页

作者： George c s LIN Department of Geography University of Hong Kong

History has brought us into a significant moment when the majority of the human kind has taken up resi-dence in urban settlements. The focus of global urbanization has shifted to the developing world and the center of manufacturing is no longer confined to the Global North. This paper provides a periodical assessment of the current status of china's urban transformation in the global context of a shifting emphasis of industrialization and urbaniza-tion. china's phenomenal urban transformation deserves a special attention not only because of its unparalleled scale and speed but also because of its distinct trajectory of growth that does not conform to normal theoretical ex-pectations. The results of assessment revealed an urban economy with remarkable hybridity, a s.c.ety that is in-creasingly stratified, polarized, and segregated, and a juxtaposed urban space undergoing restless and pervasive transformation. A decentering world should entail a decentering knowledge production. A critical reflection upon the chinese patterns and processes of urban transformation has identified 4 main issues with great potentials for inno-vative knowledge production, namely: 1) privatization and economic development; 2) state, s.c.ety, and space; 3) urbanization of capital, labor, and land; and 4) the environment and chinese political ecology. The paper closes with the remark that a rapidly transforming urban china has presented itself as a fertile and resourceful testing ground for critical and innovative geographic enquiries.

关键词： urban geography urbanization chinese cities political economy china

compressive strength, Pore size Distribution and chloride-ion Penetration of Recycled Aggregate concrete Incorporating class-F Fly Ash

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Journal of Wuhan University of Technology(Materials science) 2006年第4期21卷 130-136页

作者：寇世聪 c s Poon Department of civil and structural Engineering The Hong Kong Polytechnic University Hung HomKowloon Hong Kong

The effects of fly ash on the compressive strength, pore size distribution and chloride-ion penetration of recycled aggregate concrete were investigated. Two series of concrete mb：tures were prepared. The concrete mixtures in series I had a water-to-binder ratio and a cement content of 0.55 and 410 kg/ m^3 , respectively. The concrete rnixtures in series II had a water-to-binder ratio and a cement content of 0.45 and 400 kg/ ml respectively. Recycled aggregate was ased as 20% , 50% , and 100% replacements of natural coarse aggregate in the concrete mixtures in both series. In cutdition, fly ash was used as 0% , 25% and 35% by weight replacements of cement. The results show that the compressive strengths of the concrete decreased as the recycled aggregate and the fly ash contents increased. The total porosity and average porosity diameter of the concrete increased us the recycled aggregate content increased. Furtherrruore , an increase in the recycled aggregate content decreased the resistance to chloride ion penetration. Nevertheless, the replacement of cement by 25% fly ush improved the resistance to chloride ion penetration and pore diameters and reduced the total porosity of the recycled aggregate concrete.

关键词： durability properties recycled aggregate concrete fly ash

热致液晶共聚酯/PA6/RsMA原位复合材料 ***对热致液晶共聚酯/PA6共混体系的增容作用

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材料研究学报 2001年第3期15卷 348-352页

作者：解孝林 LI R.K.Y. TJONG s.c. 华中科技大学化学系武汉市430074 香港城市大学

选用ＶｅｃｔｒａＡ９５０热致液晶共聚酯（ＬＣＰ），制备热致液晶共聚酯（ＬＣＰ）／聚ＭＫＲ６（ＰＡ６）／苯乙烯一马来酸酐无规共聚物（ＲＳＭＡ）三元共混物，采用注射成型的方法实现原位复合测定复合材料的熔体流变性能、... 详细信息

选用ＶｅｃｔｒａＡ９５０热致液晶共聚酯（ＬＣＰ），制备热致液晶共聚酯（ＬＣＰ）／聚ＭＫＲ６（ＰＡ６）／苯乙烯一马来酸酐无规共聚物（ＲＳＭＡ）三元共混物，采用注射成型的方法实现原位复合测定复合材料的熔体流变性能、ＦＴＩＲ光谱、动态力学性质和共混物形态结构，研究了ＲＳＭＡ对聚酰胺６／热致液晶共聚酯共混体系的增容作用．结果表明，ＲＳＭＡ的加入提高了ＬＣＰ／ＰＡ６共混体的熔体粘度；ＲＳＭＡ与ＬＣＰ和ＰＡ６发生酯化、酰胺化反应，改善了ＬＣＰ与ＰＡ６之间的相容性，使两者的玻璃化温度相互靠近，提高了ＬＣＰ在ＰＡ６基体中的分散，增强了两相之间的界面粘接．

关键词：热致液晶共聚酯聚酰胺6 苯乙烯-马来酸酐无规共聚物增容作用改性原位复合材料

A Note on the Dynamics of the Logistic Family Modified by Fuzzy Numbers

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Acta Mathematicae Applicatae sinica 2022年第4期38卷 741-752页

作者： J.s.c.NOVAs Department of Applied Mathematics and statistics Technical University of CartagenaC/Doctor Flemming Sn30202CartagenaSpain

In this paper,we consider a modification of the well-known logistic family using a family of fuzzy *** dynamics of this modified logistic map is studied by computing its topological entropy with a given *** computation allows us to characterize when the dynamics of the modified family is ***,some attractors that appear in bifurcation diagrams are ***,we will show that the dynamics induced by the logistic family on the fuzzy numbers need not be complicated at all.

关键词： logisitic family topological entropy chaos Zadeh's extension fuzzy numbers

The myth of “minima” and “maxima”,the species of Physalis in the Indian subcontinent

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植物分类学报 2007年第2期45卷 239-245页

作者： Vatsavaya s RAJU c s REDDY K G RAJARAO Department of Botany Kakatiya UniversityWarangal 506009 India Forestry & Ecology Division National Remote Sensing AgencyHyderabad 500008 India Department of Botany Andhra UniversityWaltair 530003 India

The status of the names, Physalis minima L. and P. maxima Mill. (solanaceae), and their alleged presence on the Indian subcontinent are discussed. The issues of nativity and identity of Linnaean Physalis minima are long-debated while the use of the name P. maxima Mill. and its report from India are recent. The available evidence indicates that the name "P. minima L." is misapplied to two different elements, viz., P. angulata L. and P. lagascae Roem. & schult. The name Physalis minima L. may be rejected as nomen confusum, for which the paper provides the primary information. As on today, it is submerged under the synonymy of P. angulata L. The correct name for the widely known P. minima is P. lagascae. The name "P. maxima Mill." applied to the escape and naturalized weed in the Indian subcontinent and elsewhere is to be substituted by P. pruinosa L., a name misapplied to P. grisea (Waterf.) M. Martínez.

关键词：酸浆属植物酸浆值植物分类植物命名