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81.
Summary The binary and ternary copolymers are synthesized by free-radical initiated binary copolymerization of citraconic anhydride (CA) with acrylamide (AAm) and terpolymerization of acrylamide (AAm) – citraconic anhydride (CA) – vinyl acetate (VA) monomer system. Co- and terpolymerization were carried out in the presence of benzoyl peroxide (BPO) as an initiator at 70 °C in benzene under nitrogen atmosphere. Structure and monomer unit composition of the copolymers, obtained from a wide range of monomer feed were determined by elemental analysis. Structural peculiarities of synthesized PAAm, [poly (AAm-alt-CA)] and [poly(AAm-co-CA-co-VA)] were characterized by using Fourier Transform Infrared (FTIR), Uv–vis, 1H-NMR, X-ray diffraction (XRD), elemental analysis, analytical methods (titration methods) and viscometric measurements.  相似文献   
82.
The radical‐initiated terpolymerization of 3,4‐dihydro‐2H‐pyran (DHP), maleic anhydride (MA), and vinyl acetate (VA), which were used as a donor–acceptor–donor system, was carried out in methyl ethyl ketone in the presence of 2,2′‐azobisisobutyronitrile as an initiator at 65°C in a nitrogen atmosphere. The synthesis and characterization of binary and ternary copolymers, some kinetic parameters of terpolymerization, the terpolymer‐composition/thermal‐behavior relationship, and the antitumor activity of the synthesized polymers were examined. The polymerization of the DHP–MA–VA monomer system predominantly proceeded by the alternating terpolymerization mechanism. The in vitro cytotoxicities of poly(3,4‐dihydro‐2H‐pyran‐alt‐maleic anhydride) [poly(DHP‐alt‐MA)] and poly(3,4‐dihydro‐2H‐pyran‐co‐maleic anhydride‐co‐vinyl acetate) [poly(DHP‐co‐MA‐co‐VA)] were evaluated with Raji cells (human Burkitt lymphoma cell line). The antitumor activity of the prepared anion‐active poly(DHP‐alt‐MA) and poly(DHP‐co‐MA‐co‐VA) polymers were studied with methyl–thiazol–tetrazolium testing, and the 50% cytotoxic dose was calculated. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2352–2359, 2005  相似文献   
83.
Perception of universal facial beauty has long been debated amongst psychologists and anthropologists. In this paper, we perform experiments to evaluate the extent of universal beauty by surveying a number of diverse human referees to grade a collection of female facial images. Results obtained show that there exists a strong central tendency in the human grades, thus exhibiting agreement on beauty assessment. We then trained an automated classifier using the average human grades as the ground truth and used it to classify an independent test set of facial images. The high accuracy achieved proves that this classifier can be used as a general, automated tool for objective classification of female facial beauty. Potential applications exist in the entertainment industry, cosmetic industry, virtual media, and plastic surgery.  相似文献   
84.
Internet contributes to the development of science and facilitates scientific demeanors while it also serves as a ground for academic misdemeanors. Recent studies indicate that Internet facilitates and spreads academic dishonesty. The purpose of the current study is to investigate the extent of involvement of Turkish university students in academic dishonesty practices facilitated through Internet (i.e. e-dishonesty) and to question the conditions which lead to e-dishonesty. Three hundred and forty nine education faculty students from the most populated state university in Turkey were administered two Likert-Scale questionnaires developed by the researchers. After the reliability and validity conditions were met, two exploratory factor analyses were conducted. The first one revealed the factors constituting common types of e-dishonesty among undergraduate students which were fraudulence, plagiarism, falsification, delinquency, and unauthorized help. The second factor analysis exhibited individual and contextual factors triggering e-dishonesty which were named as individual factors, institutional policies and peer pressure. Results of both analyses are discussed and suggestions for further research are provided.  相似文献   
85.
Polychelates were synthesized by the addition of aqueous solutions of copper(II), cadmium(II), and nickel(II) chlorides to aqueous solutions of poly(maleic anhydride‐alt‐acrylic acid) [poly(MA‐alt‐AA)] in different pH media. The thermal properties of poly(MA‐alt‐AA) and its metal complexes were investigated with thermogravimetry and differential scanning calorimetry (DSC) measurements. The polychelates showed higher thermal stability than poly(MA‐alt‐AA). The thermogravimetry of the polymer–metal complexes revealed variations of the thermal stability by complexation with metal ions. The relative thermal stabilities of the systems under investigation were as follows: poly(MA‐alt‐AA)–Cd(II) > poly(MA‐alt‐AA)–Cu(II) > poly(MA‐alt‐AA)–Ni(II) > poly(MA‐alt‐AA). The effects of pH on the complexation and gravimetric analysis of the polychelates were also studied. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3926–3930, 2006  相似文献   
86.
Scheduling problems are becoming more and more complex everyday. This makes the current rules and algorithms difficult to comply with the requirements. New machines with the capabilities of processing more than one jobs is being developed. Sometimes one job is divided into parts and processed by more than one machine at the same time. These make the current algorithms insufficient. Artificial intelligence technologies, especially expert systems are proven to deal with such dynamic complex problems in several domains. In this study, an example of such a complex problem is introduced and knowledge-based scheduling for these kind of problems is elaborated with a real life industrial example.  相似文献   
87.
The aim of this paper was to investigate the feasibility of the removal of phosphate from aqueous solution by electro-coagulation (EC). The current density (CD) between 2.5 and 10 mA cm(-2) and duration in the limits of 5-20 min were tried for different concentrations. In order to determine optimal operating conditions, the EC process used for the phosphate removal was examined in dependence with the CD, initial concentrations and time. The results of the experimental batch processing showed high effectiveness of the EC method in removing phosphate from aqueous solutions.  相似文献   
88.
Artar A  Yanik AA  Altug H 《Nano letters》2011,11(9):3694-3700
We experimentally demonstrate for the first time a very compact plasmonic hetero-oligomer structure where the multiple radiant and subradiant modes can be tailored independently. Unlike previous approaches based on collective excitations in complex plasmonic systems, we show precise engineering of resonances leading to simultaneous spectral overlap of multiple plasmonic modes with opposite radiative character. This asymmetric behavior combined with inherent spatial features of the structure leads to directional double Fano resonances as shown with numerical analysis. A model based on temporal coupled mode theory is also provided to describe the double Fano behavior.  相似文献   
89.
New point‐of‐care diagnostic devices are urgently needed for rapid and accurate diagnosis, particularly in the management of life‐threatening infections and sepsis, where immediate treatment is key. Sepsis is a critical condition caused by systemic response to infection, with chances of survival drastically decreasing every hour. A novel portable biosensor based on nanoparticle‐enhanced digital plasmonic imaging is reported for rapid and sensitive detection of two sepsis‐related inflammatory biomarkers, procalcitonin (PCT) and C‐reactive protein (CRP) directly from blood serum. The device achieves outstanding limit of detection of 21.3 pg mL?1 for PCT and 36 pg mL?1 for CRP, and dynamic range of at least three orders of magnitude. The portable device is deployed at Vall d'Hebron University Hospital in Spain and tested with a wide range of patient samples with sepsis, noninfectious systemic inflammatory response syndrome (SIRS), and healthy subjects. The results are validated against ultimate clinical diagnosis and currently used immunoassays, and show that the device provides accurate and robust performance equivalent to gold‐standard laboratory tests. Importantly, the plasmonic imager can enable identification of PCT levels typical of sepsis and SIRS patients in less than 15 min. The compact and low‐cost device is a promising solution for assisting rapid and accurate on‐site sepsis diagnosis.  相似文献   
90.
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