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81.
82.
In order to improve upon certain properties of gelatin graft copolymerization of acrylonitrile (AN) and methacrylonitrile (MAN) onto gelatin has been studied in aqueous medium using γ rays as a source of initiation. Optimum conditions for affording maximum percentage of grafting have been evaluated as a function of various reaction parameters. The grafted polyacrylonitrile (PAN) was isolated from the graft copolymer by acid hydrolysis, and the average molecular weight (Mv) of the isolated polymer has been determined viscometrically. The graft copolymers were characterized by IR spectroscopic methods and thermogravimetric analysis (TGA). Acrylonitrile was found to be more reactive than methacrylonitrile toward graft copolymerization. © 1994 John Wiley & Sons, Inc. 相似文献
83.
Scientometrics of the international journal Scientometrics 总被引:4,自引:0,他引:4
An analysis of 1317 papers published in first fifty volumes during 1978 to 2001 of the international journal Scientometrics indicates the heterogeneity of the field with emphasis on scientometric assessment. The study indicates that the US share of papers is constantly on the decline while that of the Netherlands, India, France and Japan is on the rise. The research output is highly scattered as indicated by the average number of papers per institution. The scientometric output is dominated by the single authored papers, however, multi-authored papers are gaining momentum. Similar pattern has been observed for domestic and international collaboration. 相似文献
84.
Anita R Jindal Alistair S Grandison 《Journal of the science of food and agriculture》1992,58(4):511-517
Chhana is a traditional Indian product used widely in the confectionery industry. It is produced from cow's milk by a combination of heat and acid coagulation. Chhana whey contains about 6% milk solids yet the vast majority is wasted which leads to pollution problems. This study describes the chemical composition and various options for utilisation of chhana whey using membrane processes. Chhana whey powder containing 956 g kg?1 total solids, 750 g kg?1 lactose, 21 g kg?1 protein. 60 g kg?1 fat, 65 g kg?1 ash was produced following concentration of chhana whey by reverse osmosis. Chhana whey protein concentrate powders containing 270, 350, 400 and 580 g kg?1 protein were produced following ultrafiltration or diafiltration of chhana whey. 相似文献
85.
Within a polymer thin film, free volume elements have a wide range of size and topology. This broad range of free volume element sizes determines the ability for a polymer to perform molecular separations. Herein, six permeable thermally rearranged (TR) polymers and their precursors were studied. Using atomistic models, cavity size (free volume) distributions determined by a combination of molecular dynamics and Monte Carlo methods were consistent with experimental observation that TR polymers are more permeable than their precursors. The cavity size distributions determined by simulation were also consistent with free volume distributions determined by positron annihilation lifetime spectroscopy. The diffusion, solubility and permeation of gases in TR polymers and their precursors were also simulated at 308 K, with results that agree qualitatively with experimental data. 相似文献
86.
In the present work we describe the successful application of spiro[1H-isoindole-1,9′-[9H]xanthen]-3(2H)-one, 3′,6′-bis(diethylamino)-2-[(1-methylethylidene)amino](“FD1”) as a “turn-on” early aluminum corrosion detector in epoxy coatings. Electrospray ionization mass spectrometry (ESI-MS) and 1H NMR investigations have revealed that the non-fluorescent FD1 is sensitive to low pH due to its acid-catalyzed hydrolysis to Rhodamine B hydrazide (RBH) that subsequently becomes protonated to its fluorescent ring-opened form. Both clear and filled FD1-containing smart epoxy coatings were capable of sensing acidic pH produced at the anodic site of localized aluminum corrosion at a low indicator concentration (0.5 wt%), which was demonstrated by the observation of fluorescent, bright-orange areas corresponding to localized pitting corrosion of the aluminum substrate illuminated by a handheld UV lamp. Therefore, early corrosion of aluminum can be easily and nondestructively detected via our “turn-on” fluorescence strategy. 相似文献
87.
88.
Nur Fatihah Mohd Yatim Masitah Abd. Rahim Kavitha Menon Faisal Muti Al-Hassan Rahimah Ahmad Anita Bhajan Manocha Mohamed Saleem Badrul Hisham Yahaya 《International journal of molecular sciences》2014,15(5):8835-8845
Both α- and β-thalassaemia syndromes are public health problems in the multi-ethnic population of Malaysia. To molecularly characterise the α- and β-thalassaemia deletions and mutations among Malays from Penang, Gap-PCR and multiplexed amplification refractory mutation systems were used to study 13 α-thalassaemia determinants and 20 β-thalassaemia mutations in 28 and 40 unrelated Malays, respectively. Four α-thalassaemia deletions and mutations were demonstrated. −−SEA deletion and αCSα accounted for more than 70% of the α-thalassaemia alleles. Out of the 20 β-thalassaemia alleles studied, nine different β-thalassaemia mutations were identified of which βE accounted for more than 40%. We concluded that the highest prevalence of (α- and β-thalassaemia alleles in the Malays from Penang are −−SEA deletion and βE mutation, respectively. 相似文献
89.
Anke H?llig Anita Schug Astrid V. Fahlenkamp Rolf Rossaint Mark Coburn Argon Organo-Protective Network 《International journal of molecular sciences》2014,15(10):18175-18196
Argon belongs to the group of noble gases, which are regarded as chemically inert. Astonishingly some of these gases exert biological properties and during the last decades more and more reports demonstrated neuroprotective and organoprotective effects. Recent studies predominately use in vivo or in vitro models for ischemic pathologies to investigate the effect of argon treatment. Promising data has been published concerning pathologies like cerebral ischemia, traumatic brain injury and hypoxic ischemic encephalopathy. However, models applied and administration of the therapeutic gas vary. Here we provide a systematic review to summarize the available data on argon’s neuro- and organoprotective effects and discuss its possible mechanism of action. We aim to provide a summary to allow further studies with a more homogeneous setting to investigate possible clinical applications of argon. 相似文献
90.
Nelaka Govinna Papatya Kaner Davette Ceasar Anita Dhungana Cody Moers Katherine Son Ayse Asatekin Peggy Cebe 《Polymer International》2019,68(2):231-239
Nonwoven super‐hydrophobic fiber membranes have potential applications in oil–water separation and membrane distillation, but fouling negatively impacts both applications. Membranes were prepared from blends comprising poly(vinylidene fluoride) (PVDF) and random zwitterionic copolymers of poly(methyl methacrylate) (PMMA) with sulfobetaine methacrylate (SBMA) or with sulfobetaine‐2‐vinylpyridine (SB2VP). PVDF imparts mechanical strength to the membrane, while the copolymers enhance fouling resistance. Blend composition was varied by controlling the PVDF‐to‐copolymer ratio. Nonwoven fiber membranes were obtained by electrospinning solutions of PVDF and the copolymers in a mixed solvent of N,N‐dimethylacetamide and acetone. The PVDF crystal phases and crystallinities of the blends were studied using wide‐angle X‐ray diffraction and differential scanning calorimetry (DSC). PVDF crystallized preferentially into its polar β‐phase, though its degree of crystallinity was reduced with increased addition of the random copolymers. Thermogravimetry (TG) showed that the degradation temperatures varied systematically with blend composition. PVDF blends with either copolymer showed significant increase of fouling resistance. Membranes prepared from blends containing 10% P(MMA‐ran‐SB2VP) had the highest fouling resistance, with a fivefold decrease in protein adsorption on the surface, compared to homopolymer PVDF. They also exhibited higher pure water flux, and better oil removal in oil–water separation experiments. © 2018 Society of Chemical Industry 相似文献