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Mechanical properties of polypropylene Composites Reinforced with Macadamia Nutshell Fibers

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Journal of Renewable Materials 2019年第10期7卷 1047-1053页

作者： Joyce de p.Cipriano N.C.Zanini I.R.Dantas D.R.Mulinari Faculdade de Tecnologia/FAT/UERJ Rodovia Presidente Dutra km 298 Polo IndustrialResende27537-000Brazil Universidade Federal Fluminense Avenida dos Trabalhadores420Vila Santa CecíliaVolta Redonda27255-125Brazil

The use of natural fibers as an additive in polymeric matrices has attracted interest of the automotive industries,for its low cost,mechanical properties,biodegradability and ***,the hydrophilic nature of the fiber makes polymer compatibility *** surface treatments can be used to enhance the fiber/matrix *** the present work,polypropylene(pp)composites reinforced with fibers from macadamia nutshell were obtained and *** nutshell fibers were treated by an alkaline treatment with sodium hydroxide(NaOH 4%)to improve adhesion between fibers and *** were characterized by techniques of Scanning Electron Microscopy(SEM)and X-Ray Diffraction(XRD).The pp was mixed with the macadamia fibers(treated and untreated),in proportions of 5 and 10%(wt/wt)using a thermokinetic *** tensile,flexural and impact specimens(pure pp and composites)were prepared by an injection molding process and tested for evaluation of mechanical *** results showed that the insertion of treated fibers in the pp matrix increased the stiffness of the ***,the composites reinforced with untreated fibers presented higher impact energy absorption when compared to composites reinforced with treated fibers.

关键词： Macadamia nutshell polypropylene alkaline treatment mechanical properties

Regeneration of tree species in the sub-tropical forest of Alaknanda Valley, Garhwal Himalaya, India

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Forestry Studies in China 2013年第2期15卷 89-97页

作者： Radha BALLABHA J. K. TIWARI p. TIWARI Department of Botany and Microbiology HNB Garhwal UniversitySrinagar Garhwal 246174 Uttarakhand India

We studied the regeneration of tree species in the sub-tropical forest of Alaknanda Valley in Garhwal Himalaya, India. The overall regeneration status was fairly good in the study area. Seedling density ranged between 520 and 1,240 seedlings per ha while the density of saplings varied between 400 and 800 saplings per ha. Out of eight sites studied, five sites, viz., A1, A2, B1, B2 and C2 contained the highest number of seedlings （280-480 per ha） and saplings ,（200-440 per ha） for pinus roxburghfi and remaining three sites viz., C1, D1 and D2 represented the highest number of seedlings （240-400 per ha） and saplings （200-240 per ha） for Anogeissus latifolius. The DBH class distribution of the tree species revealed that the highest number of individuals was concentrated in the lower diameter classes while smallest numbers were found in the higher diameter classes. Species such as Acacia catechu, Anogeissus latifolius, Dalbergia sissoo, Engelhardtia spicata, Lannea coromandelica, Mallotus philippensis and pinus roxburghii have the larg- est number of saplings and seedlings in the lower DBH classes, suggesting that they have good regeneration potential. Other spec es such as Aegle marmelos, Bauhinia variegata, Bombax ceiba, Cassia fistula, Erythrina variegata, Haldinia ：cordifolia, Mangifera indica, Ougeinia oojeinensis, phyllanthus emblica, Syzygium cumini, Terminalia alata and Toona hexandra have either no or very small number of saplings in the lower DBH classes which indicates that the status of these species implies poor regeneration.

关键词： Garhwal Himalaya disturbances regeneration tree species

Synthesis and electrical properties of BaBiO_(3)and high resistivity BaTiO_(3)-BaBiO_(3)ceramics

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Journal of Advanced Dielectrics 2016年第4期6卷 53-60页

作者： Nitish Kumar Stephen L.Golledge David p.Cann Materials Science School of Mechanical Industrialand Manufacturing Engineering Oregon State UniversityCorvallisOregon 97331USA School of Materials Science and Engineering The University of New South Wales New South Wales 2052 Australia CAMCOR Surface Analytical Facility University of Oregon Eugene Oregon 97403USA

Ceramics of the composition BaBiO_(3)(BB)were sintered in oxygen to obtain a single phase with monoclinic I2/m symmetry as suggested by high-resolution X-ray diffraction.X-ray photoelectron spectroscopy confirmed the presence of bismuth in two valence states—3þand 5þ.Optical spectroscopy showed presence of a direct bandgap at-2.2 eV and a possible indirect bandgap at-0.9 *** combined with determination of the activation energy for conduction of 0.25 eV,as obtained from ac impedance spectroscopy,suggested that a polaron-mediated conduction mechanism was prevalent in *** BB ceramics were crushed,mixed with BaTiO_(3)(BT),and sintered to obtain BT–BB solid *** the ceramics had tetragonal symmetry and exhibited a normal ferroelectric-like dielectric *** ac impedance and optical spectroscopy,it was shown that resistivity values of BT–BB were orders of magnitude higher than BT or BB alone,indicating a change in the fundamental defect equilibrium conditions.A shift in the site occupancy of Bi to the A-site is proposed to be the mechanism for the increased electrical resistivity.

关键词： BaBiO_(3) BaTiO_(3) conduction mechanism transport properties synchrotron X-ray photoelectron spectroscopy impedance spectroscopy defects.

MULTIpLE-SCATTERING DETERMINATION TO THE LOCAL ADSORpTION GEOMETRY OF SO_2/pd(111)

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 81-86页

作者： S. Cao J.C. Tang p. Zhu L. Wang S.L Shen Dept. of phys. Zhejiang Univ. Hangzhou 310027 China

We have calculated the sulphur 1s near edge X-ray absorption fine structure (NEXAFS) spectra of SO2 adsorbed on pd (111) in terms of the Multiple-Scattering Cluster (MSC) method. The origin of the resonances in the NEXAFS spectra has been revealed. By the MSC calculation and a (DV)-Xα study we have for the first time identified two weak features existing in S K-edge NEXAFS of SO2/pd(111) system, which are attributed to the interaction between the adsorbate and the substrate. Moreover, MSC calculation together with the reliability factor (R-factor) analysis are employed to determine the local adsorption structures. These results are broadly in agreement with those of Fourier-transform analysis of the surface extended X-ray absorption fine structure (SEXAFS).

关键词： Absorption Geometry palladium Scattering Sulfur dioxide X ray spectroscopy

Simulated Microbe Removal around Finger Rings Using Different Hand Sanitation Methods

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International Journal of Oral Science 2009年第3期1卷 136-142页

作者： Archana A. Alur Madhavi J. Rane James p. Scheetz Douglas J. Lorenz Lawrence Gettleman Ballard High School Louisville Kentucky USA School of Medicine University of Louisville Louisville Kentucky USA School of Dentistry University of Louisville Louisville Kentucky USA School of public Health & Information Sciences University of Louisville Louisville Kentucky USA

Aim It is our opinion that the CDC and the WHO have underestimated cross-contamination under examination gloves in dental clinics while wearing jewelry, such as finger rings. These agencies only ＂recommend＂ removing jewelry, and only washing hands for 15 seconds with soap and warm water before donning gloves. This study examined several washing procedures and finger rings using simulated microbes. Methodology A gloved robber hand manikin was made and fitted with a flesh disposable vinyl glove. Four fingers were fitted with rings or no ring, dusted with simulated microbes, and washed with a scrub brush for 5, 15, and 25 seconds under 20℃ and 40℃ water alone, or with liquid hand soap. Light levels （in lux） of fluorescent powder before and after washing were measured and delta scores calculated for changes in light levels, equivalent to effectiveness of hand washing procedures. A full-factorial, 3-factor analysis of variance （ANOVA） was used to test for differences among levels of the three study factors-time, temperature, and soap use. Tukey＇s post hoc honestly significant difference （HSD） test was applied to significant factors to examine pair-wise differences between factor levels. Results It was found that the longer the hands with rings were washed with a scrub brush under flowing water, the more simulated microbes were removed. By 25 seconds, all methods were essentially the same. Simulated microbes were more difficult to remove from the palm compared to the back of the hand. The liquid hand soap used in this study was more effective with warm water than cold. When given a choice of washing with cold water up to 15 seconds, it would be preferable not to use soap to remove simulated microbes. Qualitatively, the outer surface of finger rings were more effectively cleaned than the crevice below the ring, and the ring with a stone setting appeared to accumulate and retain simulated microbes more than other rings. Conclusion The most effective treatment was washing wi

关键词： dental exam gloves finger ring jewelry crosscontamination hand hygiene microbes fluorescent powder dental health care workers

New Families in the Stable Homotopy of Spheres Revisited

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Acta Mathematica Sinica,English Series 2002年第1期18卷 95-106页

作者： LIN Jin Kun Department of Mathematics. Nankai University. Tianjin 300071. p. R. China Department of Mathematics Nankai University Tianjin P. R. China

This paper constructs a new family in the stable homotopy of spheres π_(t-)S represented by h_ngoY_3 ∈E_2~6(,t) in the Adams spctral sequence which revisits the b_(n-1goY3)-elements ∈π_(-7)S con- structced in[3]. ... 详细信息

关键词： Stable homotopy of spheres Adams spectral sequence Toda-Smith spectrum Adams resolution

The Synthetic Evaluation of Warhead Overall Efficiency

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Journal of Systems Engineering and Electronics 2003年第1期14卷 12-17页

作者： Gu Xiaohui & Cao Bing College of Mechanics, Nanjing University of Science & Technology, Nanjing 210094, p. R. China College of Mechanics Nanjing University of Science & Technology Nanjmg 210094 P. R. China

The evaluation system of smart ammunition warhead overall efficiency has been established in this paper. Allkinds of evaluation methods have been analyzed. Having led the concept of hierarchical structure into technique for orderpreference by similarity to ideal solution (TOpSIS) method, we put forward the step TOpSIS method which is suitable forevaluating the overall efficiency of smart ammunition warheads. In the calculation of index weight, the graded weight cal-culus is put forward which hardly relies on the subjectivity of decision-makers and can reflect the sensitivity and compatibili-ty of the index. In the graded weight calculation, the proportional-arithmetic weight value calculus and sensitivity-compati-bility weight value calculus are given respectively.

关键词： Step analysis TOpSIS method Warhead Efficiency evaluation.

A Way to Find All the Optimal Solutions in Linear programming

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Journal of Systems Engineering and Electronics 2000年第2期11卷 11-16页

作者： Zuo Xiaode Xue Shengjia & Luo Lei(Management School, Jinan University Guangzhou 510632, p. R. China) Management School Jinan University Guangzhou 510632 P. R. China

With the expression theorem of convex polyhedron, this paper gives the general expression for the solutions in standard linear programming problems. And the calculation procedures in determining the optimal solutions ... 详细信息

关键词： Linear programming Convex polyhedron Optimal solution Simplex method

Defective maintenance of intracellular Ca2+ homeostasis is linked to increased muscle fatigability in the MG29 null mice

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Cell Research 2004年第5期14卷 373-378页

作者： Marco A. p. BROTTO,Ramakrishnan Y. NAGARAJ,Leticia S. BROTTO,Thomas M. NOSEK Department of physiology and Biophysics UMDNJ-Robert Wood Johnson Medical School piscataway NJ 08854 USA Department of physiology and Biophysics UMDNJ-Robert Wood Johnson Medical School piscataway NJ 08854 USA Department of physiology and Biophysics UMDNJ-Robert Wood Johnson Medical School piscataway NJ 08854 USA Department of physiology and Biophysics School of Medicine Case Western Reserve University Cleveland OH 44106 USA

Mitsugumin 29 (MG29) is a transmembrane protein that is normally found in the triad junction of skeletal muscle. Our previous studies have shown that targeted deletion of mg29 from the skeletal muscle resulted in abnormality of the triad junction structure, and also increased susceptibility to muscle fatigue. To elucidate the basis of these effects, we investigated the properties of Ca2+-uptake and -release in toxin-skinned Extensor Digitorium Longus (EDL) muscle fibers from control and mg29 knockout mice. Compared with the control muscle, submaximal Ca2+-uptake into the sarcoplasmic reticulum (SR) was slower and the storage of Ca2+ inside the SR was less in the mutant muscle, due to increased leakage process of Ca2+ movement across the SR. The leakage pathway is associated with the increased sensitivity of Ca2+/caffeine -induced Ca2+ release to myoplasmic Ca2+. Therefore, the increased fatigability of mutant EDL muscles can result from a combination of a slowing of Ca2+ uptake, modification of Ca2+-induced Ca2+ release (CICR), and a reduction in total SR Ca2+ content.

关键词： MG29 mutant skeletal muscle skinned fibers ECC Ca2+ uptake CICR.