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71.
Ample biodegradable eggshell powder (ESP)/wheat protein isolate (WPI) composite films were made by solution casting method of altering the WPI solution and fused with ESP particles in the percentage of 5, 10, 20, 30, and 40% (w/w) and asses the properties, i.e., physical, mechanical, and thermal as a function of ESP concentration. Determine the unification of ESP particles into the WPI matrix by X‐ray diffraction, fluorescence spectra, and SEM analysis. The data clearly showed the successful incorporation of ESP particles and good compatibility with the WPI and also mechanical properties and thermal stability of composite film increasing with the increasing ratio of ESP. Microstructural evaluation confirmed the aggregation and distribution of ESP particles within the WPI matrix and validated the results of functional properties of the WPI/ESP film. The results confirmed that the composite films have potential applications in the field of food and medicinal packaging especially for photosensitive medicines in a very simple and cheap way. POLYM. COMPOS., 37:3280–3287, 2016. © 2015 Society of Plastics Engineers 相似文献
72.
Biochemical and toxicological studies on the effect of high and low erucic acid rapeseed oil on rats
Rats were fed on diets containing rapeseed oil, either containing low or high erucic acid content as well as the hydrogenated ones for 6 weeks. Body weight gain, biochemical and pathological parameters were investigated. The data showed high body weight gain for rats fed diets containing low erucic rape oil (LERo) compared with those fed either the high erucic rape oil (HERo), the hydrogenated or the partially hydrogenated oil diets. All rats showed non significant changes for total lipids, total cholesterol, GPT and GOT, except the partially hydrogenated rape oil diet which showed significant decrease for total cholesterol. Alkaline phosphatase however showed a significant decrease, while plasma phospholipids showed significant increase in rats fed on the hydrogenated oil diet. Triglycerides indicated non significant increase except in the group that received low erucic rape oil diet. Histopathological study showed changes in all tissues examined (liver and kidney). 相似文献
73.
Oveisi H Beitollahi A Jiang X Sato K Nemoto Y Fukata N Yamauchi Y 《Journal of nanoscience and nanotechnology》2011,11(8):6926-6933
Here we report synthesis of ordered mesoporous titania films with various amounts of Ga content. The influence of Ga contents on mesostructural ordering, surface morphology, thermal stability, and anatase crystallinity is carefully investigated, by using grazing incidence small angle X-ray scattering (GISAXS), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), and Raman spectroscopy. The presence of highly dispersed Ga contents in the titania frameworks can promote the thermal stability of mesoporous titania structures, resulting that the anatase crystallization successfully proceeds without collapse of mesostructures. 相似文献
74.
75.
STUDY OBJECTIVE: To evaluate physician prescribing practices for the initial therapy for tuberculosis (TB) according to the recommendations of the Centers for Disease Control and Prevention (CDC) and American Thoracic Society (ATS). DESIGN: Cross-sectional study. SETTING: Statewide TB surveillance system in New Jersey, 1994 to 1995. PATIENTS: We studied 1,230 culture-positive TB patients who were alive at diagnosis and whose isolates were tested for isoniazid susceptibility. RESULTS: Almost all TB patients (98%) were reported from counties with an isoniazid-resistant proportion of 4% or more, which is the minimum level for implementation of an initial four-drug regimen recommended by CDC/ATS. Overall, 36% of the 1,230 patients were not initially treated with four or more drugs. Multivariate analyses found that non-Hispanic white patients were more likely to be treated with fewer than four drugs than were non-Hispanic black patients. Private practitioners and physicians at chest clinics were about five times more likely to prescribe fewer than four drugs initially than were physicians at the hospital where a national TB center is located. CONCLUSION: A substantial proportion of physicians did not initially treat their TB patients according to the CDC/ATS recommendations. The results suggest that New Jersey physicians should be better informed about the recommendation and the high level of drug resistance in the communities they serve to assure that TB patients receive appropriate initial therapy. 相似文献
76.
Saeed Ahmed Muhammad Khalid Khan Atta Ur Rehman 《International Journal of Electronics》2016,103(7):1228-1235
In this article, we develop an analytic theory for a perfect electromagnetic conductor (PEMC) plate embedded in lossy medium. The duality transformation introduced by Lindell and Sihvola is applied to study the electromagnetic wave scattering by a PEMC plate. Perfect electric conductor and perfect magnetic conductor are the limiting cases of PEMC media. Here, we study monoscattering by PEMC plate embedded in four different soil models. Numerical results are discussed and compared with the available literature. 相似文献
77.
Investigation of the effect of coagulation bath composition on PVDF/CA membrane by evaluating critical flux and antifouling properties in lab‐scale submerged MBR
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Mohammad Hossein Razzaghi Maryam Tavakolmoghadam Fatemeh Rekabdar Fatemeh Oveisi 《Water and Environment Journal》2018,32(3):366-376
Ultrafiltration membranes were prepared from blends of poly(vinylidene fluoride) (PVDF)/cellulose acetate (CA) via phase inversion method. The effect of different coagulation bath compositions on the morphology and performance of the blend membrane prepared from casting solution of PVDF/CA with ratio of 80/20 was investigated using sewage wastewater. NaCl and ethanol were used as additives of coagulation bath. Fouling analysis was conducted with Bovine Serum Albumin solution and critical flux evaluation was performed using a lab‐scale membrane bioreactor. In terms of morphological structure, the macrovoids decreased and changed to finger‐like structure. The irreversible fouling reduced and the flux recovery ratio (FRR) of the modified membranes increased remarkably while the reversible fouling caused by deposition of foulants on the surface of the membranes increased. The maximum values of FRR and critical flux of irreversibility were reached by the membrane which was prepared in the coagulation bath containing the highest concentration of NaCl. 相似文献
78.
Ayman M. Atta 《应用聚合物科学杂志》2012,124(4):3276-3285
Ultrafine well‐dispersed Fe3O4 magnetic nanoparticles were directly prepared in aqueous solution using controlled coprecipitation method. The synthesis of Fe3O4/poly (2‐acrylamido‐2‐methylpropane sulfonic acid) (PAMPS), Fe3O4/poly (acrylamide‐co‐2‐acrylamido‐2‐methylpropane sulfonic acid) poly(AM‐co‐AMPS) and Fe3O4/poly (acrylic acid‐co‐2‐acrylamido‐2‐methylpropane sulfonic acid) poly(AA‐co‐AMPS) ‐core/shell nanogels are reported. The nanogels were prepared via crosslinking copolymerization of 2‐acrylamido‐2‐methylpropane sulfonic acid, acrylamide and acrylic acid monomers in the presence of Fe3O4 nanoparticles, N,N′‐methylenebisacrylamide (MBA) as a crosslinker, N,N,N′,N′‐tetramethylethylenediamine (TEMED) and potassium peroxydisulfate (KPS) as redox initiator system. The results of FTIR and 1H‐NMR spectra indicated that the compositions of the prepared nanogels are consistent with the designed structure. X‐ray powder diffraction (XRD) and transmission electron microscope (TEM) measurements were used to determine the size of both magnetite and stabilized polymer coated magnetite nanoparticles. The data showed that the mean particle size of synthesized magnetite (Fe3O4) nanoparticles was about 10 nm. The diameter of the stabilized polymer coated Fe3O4 nanogels ranged from 50 to 250 nm based on polymer type. TEM micrographs proved that nanogels possess the spherical morphology before and after swelling. These nanogels exhibited pH‐induced phase transition due to protonation of AMPS copolymer chains. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
79.
Crosslinked acrylamide (AM) and 2‐acrylamido‐2‐methylpropanesulfonic acid (AMPS) homopolymers and copolymers were prepared by free radical solution polymerization using N,N′‐methylenebisacrylamide as the crosslinker. The chemical structures of hydrogels were characterized by FTIR analysis and the results were consistent with the expected structures. These hydrogels were used for the separation of Cd(II), Cu(II), and Fe(III) ions from their aqueous solutions. The influence of the uptake conditions such as pH, time and initial feed concentration on the metal ion binding capacity of hydrogel was also tested. The selectivity of the hydrogel towards the different metal ions tested was Cd(II) > Cu(II) > Fe(III). It was observed that the specific interaction between metal ions and ionic comonomers in the hydrogel affected the metal binding capacity of the hydrogel. The recovery of metal ions was also investigated in acid media. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
80.
Atta Ul Haq Joonwon Lim Je Moon Yun Won Jun Lee Tae Hee Han Sang Ouk Kim 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(22):3829-3833
Polymer grafting from graphitic carbon materials has been pursued for several decades. Unfortunately, currently available methods mostly rely on the harsh chemical treatment of graphitic carbons which causes severe degradation of chemical structure and material properties. A straightforward growth of polyaniline chain from the nitrogen (N)‐doped sites of carbon nanotubes (CNTs) is presented. N‐doping sites along the CNT wall nucleate the polymerization of aniline, which generates seamless hybrids consisting of polyaniline directly grafted onto the CNT walls. The resultant materials exhibit excellent synergistic electrochemical performance, and can be employed for charge collectors of supercapacitors. This approach introduces an efficient route to hybrid systems consisting of conducting polymers directly grafted from graphitic dopant sites. 相似文献