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81.
Md. Forhad Mina Md. Akramul Haque Md. Khairul Hassan Bhuiyan Md. Abdul Gafur Yukihiro Tamba Tsutomu Asano 《应用聚合物科学杂志》2010,118(1):312-319
Nanocomposites of isotactic polypropylene (iPP) and multiwalled carbon nanotubes (MWCNTs) with various contents of MWCNTs were fabricated by double molding techniques. X‐ray diffraction measurements reveal a development of α‐crystal with lamellar stacks having a long period of 150 Å in the neat iPP that increases to 165 Å in 2 wt % MWCNTs‐loaded composites, indicating that MWCNTs enhance crystallization of iPP as a nucleating factor. Mechanical properties, such as tensile strength, flexural strength, Young's modulus, tangent modulus, and microhardness are found to increase with increasing MWCNTs content. Thermal analyses represent an increase of crystallization and melting temperatures and a decrease of thermal stability of the composites with increasing MWCNTs. Changes in structural, mechanical, and thermal properties of the composites due to the addition of MWCNTs are elaborately discussed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
82.
83.
Fernanda Peyronel Joseph Cooney Erzsebet Papp-Szabo Silvana Martini David Pink 《Journal of the American Oil Chemists' Society》2023,100(12):961-974
Three oleogelator molecules (Triacontane (TC), Stearic acid (SA), and Behenyl Lignocerate (BL)) were studied individually, in pairs, or all together to make an oleogel using triolein as the oil. WAXS, SAXS and USAXS were used to elucidate the solid structures from angstroms to a few micrometers. A two-dimensional mapping of atomic positions for each molecule was carried out to understand the crystalline multilayer structures formed. We assumed that the molecules were rigidly extended and that they underwent no significant (hindered) rotations so that the free energy is determined by the Lennard-Jones interactions of closely packed multilayers. TC molecules were predicted to form a tilt angle of , yielding a SAXS line at Å─1, in acceptable agreement with the measured . For SA crystals (predicted) yielding a SAXS line at compared to (observed). No mixed crystals were observed for any pair of molecules or when all three were used. USAXS data showed that SA forms large nanocrystals compared to TC and BL. All three combinations of molecular pairs showed basic scatterers smaller or similar to those of individual molecules. The theory presented here, together with the experimental results, showed why no mixed crystals are formed from two or all three molecules. Data from the USAXS region suggested that, when using all three molecules, a more compact fractal structure was obtained, compared with those if one or two of the molecules were used. 相似文献
84.
85.
Rosa M. MARTICORENA Joyce HUNTER Ramona COOK Mina KASHANI Julia DELACRUZ Elizabeth PETERSHOFER Steve MACLEOD Niki DACOURIS Philip A. McFARLANE Sandra M. DONNELLY Marc B. GOLDSTEIN 《Hemodialysis international. International Symposium on Home Hemodialysis》2009,13(3):316-321
The preference for fistulae as the hemodialysis access of choice has led to a significant number of accesses that are less than ideal for cannulation. Buttonhole cannulation is ideal for such accesses, but the technique for creation provides major challenges. In 12 patients, buttonhole tunnel tracks were created by leaving the polyurethane catheter of a Clampcath® hemodialysis needle indwelling for 10 days after the initial cannulation. After each dialysis the catheter was flushed, and dressed with an antibacterial ointment and gauze. Dialysis was carried out via the catheter during that time. After day 10, the catheter was removed, the tunnel track covered with an antibacterial dressing and the tunnel track was cannulated with a dull buttonhole needle at the next dialysis. Successful buttonhole accesses were created in 11 patients after 10 days, the 12th patient required a single sharp needle cannulation before using dull needles. During the first 2 weeks of dull needle cannulation both pain experienced on cannulation and the difficulty cannulating the access were significantly less than in the classical buttonhole technique (P<0.01). Complications during the follow-up period (6 months–1.5 years) included difficulty cannulating with a dull needle (22) and antibacterial agent induced contact dermatitis (4). There was no episode of sepsis or tunnel track infection. Initial cannulation of the fistula using a Clampcath® hemodialysis needle, leaving the polyurethane catheter indwelling for 10 days, is a simple, safe, and effective technique for the creation of buttonhole tunnel tracks. 相似文献
86.
Micrometer‐sized polymer particles with encapsulated ultraviolet (UV) absorbent, fluorescent agent, and blue pigment were successfully prepared by microsuspension polymerization utilizing the Self‐assembling of Phase Separated Polymer method. The particles were characterized by optical microscope and particle size distribution analysis, and they were evaluated on their usefulness for cosmetic using UV spectrometry, colorimetry, VISIA? Evolution, and bioassay. The capsule particles had multifunctional properties, which are very attractive in the cosmetic field, especially in whitening, brightening, the improvement of face‐texture, and less noticeable pores in face, as well as the protection from UV. Moreover, bioactivities of the particles under the UV irradiation, which were examined with the films prepared from capsule components, revealed not only makeup effect but also the activation of human epidermal keratinocytes. The results suggest the importance of blue light in the field of cosmetics. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
87.
Mina Martini Iolanda Altomonte Rossana Pesi Maria Grazia Tozzi Federica Salari 《International Dairy Journal》2013,28(1):36-39
A trial was carried out on seven Massese ewes, from which individual milk samples were taken during lactation. All the enzyme activities investigated (oxidase activity of xanthine oxidoreductase, gamma-glutamyltranspeptidase, alkaline phosphatase and 5′-nucleotidase) were affected by the lactation phase, with the exception of the dehydrogenase activity of xanthine oxidoreductase (XOR). A higher oxidase activity (XO) of XOR was found when the diameter of milk fat globules was smaller. In addition, the absence of XO in colostrum led to the hypothesis that its antibacterial role is independent of its activity. The increase in alkaline phosphatase activity during lactation requires further research to better define the criteria for pasteurised sheep milk. 相似文献
88.
Xiaoquan Lu Junying Ma Ruiping Sun Mina Nan Fanfu Meng Jie Du Xiaoyan Wang Hui Shang 《Electrochimica acta》2010,56(1):251-256
Substituent effects of iron porphyrin complexes on the structures and kinetic processes have been examined for the first time. Basing on the premise that iron porphyrin is functional analogous to heme, a series of iron porphyrin derivatives bearing different substituents at the meso positions of the corrole ring are investigated as to their electrochemistry, the relationships among the electron transfer (ET) processes, their structures, and orbital energies. The good coherence between the experiment and theory indicates that the ET rate can be accelerated when electron-donating substituents are introduced to the iron porphyrin ring. Finally, the implications of the results are discussed in the influence of stability of iron porphyrin complexes on the ability to carry molecular oxygen, which may suggest it possible to dominate the biological activity of heme by selecting the appropriate substituents to iron porphyrin ring. 相似文献
89.
In this introduction, the authors discuss work–family research in the context of occupational health psychology (OHP), describe the special contributions of articles in this special issue, and outline directions for the next generation of research in the field of OHP. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
Angel M Zamarreo Jose M García‐Mina Rodrigo G Cantera 《Journal of the science of food and agriculture》2003,83(15):1607-1612
This paper describes a new and convenient methodology for studying the performance of products used in the treatment of ruminal acidosis. The method is based on potentiometric titration of the increase in buffer capacity and acid consuming capacity after the addition of products to a suitable medium at physiological rumen pH values. The testing medium is a mixture of buffer substances (phosphate, maleate and volatile fatty acids) that mimics real ruminal fluid in chemical composition, pH and temperature, providing useful experimental results allowing easy testing of antacids. This methodology was applied to the testing of four raw materials (sodium bicarbonate, two calcium carbonates and magnesium oxide). Results in good agreement with theoretical predictions and field experience were obtained. Copyright © 2003 Society of Chemical Industry 相似文献