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1.
Diels-Alder cycloaddition of furfural to C60 in toluene has been realised. UV-VIS, FTIR and 1H-NMR investigations suggest that the conjugated structure of furfural was changed into a non-conjugated structure in the product.  相似文献   
2.
Energy demand is increasing by the years. Population's needs and technological investments bring the new approach about generating energy. It is considered that fossil fuels will not be able to respond to all energy requirements after approximately 150 years. Turkey imports nearly all of its petroleum and so this causes major economic problems. Turkey, as a major cereal producer, has a huge potential to grow energy crops and other cellulosic biomaterials and can obtain plant's residues, which are suitable to produce second generation bioethanol (SGB). With domestic production, bioethanol can reduce the dependence of petroleum for Turkey, and greenhouse gas emissions can be decreased. Taking into account Turkey's situation in fuel–oil consumption, costliness of gasoline and environmentally hazardous specification of fossil fuels, bioethanol gains more importance and increases in value. Especially, SGB production is rising. Foodstuffs are valuable, and producing ethanol from directly those materials can cause a crisis in Turkey because lignocellulosic bioethanol is becoming prominent. In this regard, bioethanol production in Turkey becomes a major alternative to petroleum and may be a key to new and clean energy source. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
3.
Poly (methyl methacrylate) (PMMA)–starch composites were prepared by emulsion polymerization technique for L‐asparaginase (L‐ASNase) immobilization as highly activated support. The hydroxide groups on the prepared composites offer a very simple, mild and firm combination for enzyme immobilization. The pure PMMA and PMMA‐starch composites were characterized as structural, thermal and morphological. PMMA‐starch composites were found to have better thermal stability and more hydrophilic character than pure PMMA. L‐ASNase was immobilized onto PMMA‐starch composites contained the different ratio of starch (1, 3, 5, and 10 wt %). Immobilized L‐ASNase showed better performance as compared to the native enzyme in terms of thermal stability and pH. Km value of immobilized enzyme decreased approximately eightfold compared with the native enzyme. In addition to, immobilized L‐ASNase was found to retain 60% of activity after 1‐month storage period at 4 °C. Therefore, PMMA‐starch composites can be provided more advantageous in terms of enzymatic affinity, thermal, pH and storage stability as L‐ASNase immobilization matrix. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43421.  相似文献   
4.
5.
Infrared absorption in polymer and glass-based thick film resistors has been measured between 400 and 1500 cm–1. Sample structures are discussed on the basis of X-ray, Fourier transform-infrared and resistance-temperature data. It is shown that in polymer-based thick film resistors, the particulate phase is mostly responsible for the infrared absorption between 400 and 900 cm–1, whereas the infrared absorption at higher wave numbers is related to the continuous phase. In glass-based thick film resistors, absorption is mostly determined by the highly doped glass. The results indicate that thick film resistors can be used as an absorbent coating in the 400–1500 cm–1 region by suitable selection of the continuous and particulate phases.  相似文献   
6.
Lipoid proteinosis is a rare autosomal recessive disorder with a chronic, benign course. There is no generally accepted systemic therapy apart from the experimental oral use of dimethyl sulphoxide (DMSO) and etretinate in two single cases. We treated two sisters and an unrelated man with lipoid proteinosis with longterm oral DMSO (60 mg/kg/d). At the end of an average treatment time of 3 years, DMSO was withdrawn because it produced no beneficial effects with regard to their skin, mucosal lesions or hoarseness. Additionally, one patient showed progression of her disease with worsening hoarseness and onset of dyspnea, requiring surgical removal of vocal cord infiltrates. Three patients with lipoid proteinosis failed to show any beneficial response to long term treatment with DMSO.  相似文献   
7.

In this paper, we introduced some similarity measures for bipolar neutrosophic sets such as; Dice similarity measure, weighted Dice similarity measure, Hybrid vector similarity measure and weighted Hybrid vector similarity measure. Also we examine the propositions of the similarity measures. Furthermore, a multi-criteria decision-making method for bipolar neutrosophic set is developed based on these given similarity measures. Then, a practical example is shown to verify the feasibility of the new method. Finally, we compare the proposed method with the existing methods in order to demonstrate the practicality and effectiveness of the developed method in this paper.

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8.
A new polymeric adsorbent bearing both hydrophilic groups providing swelling in water and amidoxime groups for chelating with uranyl ions (UO22+), has been developed and its adsorptive ability for recovering uranium from aqueous media has been investigated. The polymers obtained by irradiating the solution of polyethylene glycol (PEG) in acrylonitrile (AN) are defined as interpenetrating polymer networks (IPNs) and the adsorbent has been obtained by applying the amidoximation reaction to the IPNs with a conversion ratio of ∼ 60%. Kinetics of the conversion reaction of the cyano (CN) group to the amidoxime (HONCNH2) group has been studied by reacting with hydroxylamine (NH2OH) solution at a molar ratio of NH2OH/CN = 1.25 in aqueous media at three different temperatures, 30, 40, and 50°C, for 3–4 days. The degree of amidoximation ratio was determined by UO22+ ion adsorption and FTIR spectrometry and the UO22+ ion adsorption values were found by both UV and gamma spectrometry and also by gravimetry. It was found that the polymeric adsorbent has a very high adsorption ability for uranium and quite a good stability in aqueous media. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 2475–2480, 1997  相似文献   
9.
In this study, the case properties and diffusion kinetics of AISI 440C and AISI 52100 steels borided in Ekabor-II powder were investigated by conducting a series of experiments at temperatures of 1123, 1173 and 1223 K for 2, 4 and 8 h.The boride layer was characterized by optical microscopy, X-ray diffraction technique and micro-Vickers hardness tester. X-ray diffraction analysis of boride layers on the surface of the steels revealed the existence of FeB, Fe2B and CrB compounds.The thickness of boride layer increases by increasing boriding time and temperature for all steels. The hardness of the boride compounds formed on the surface of steels AISI 52100 and AISI 440C ranged from 1530 to 2170 HV0.05 and 1620 to 1989 HV0.05, respectively whereas Vickers hardness values of untreated steels AISI 440C and AISI 52100 were 400 HV0.05 and 311 HV0.05, respectively. The activation energies (Q) of borided steels were 340.426 kJ/mol for AISI 440C and 269.638 kJ/mol for AISI 52100. The growth kinetics of the boride layers forming on the AISI 440C and AISI 52100 steels and thickness of boride layers were also investigated.  相似文献   
10.
Poly(2,2′-(1,4-phenylenedivinylene) bis-8-hydroxyquinaldine)/multi-walled carbon nanotube-modified glassy carbon electrode (poly(PBHQ)/MWCNTs/GCE) was developed and applied for the electrochemical estimation of vitamin B-12 (VB-12). Compared to multi-walled carbon nanotube-modified glassy carbon electrode, well-defined redox peaks were observed in phosphate buffer solution at pH 2.5. In contrast with the ill-defined redox peaks observed with unmodified glassy carbon electrode surfaces. The poly(2,2′-(1,4-phenylenedivinylene) bis-8-hydroxyquinaldine-based electrode displayed a good linear range of 0.1 to 10 μM VB-12 with a low detection limit of 0.01 μM. To further study the practical applicability of the proposed sensing procedure, the estimation of real samples was employed with satisfactory consequences. In addition, MWCNTs were used as sorbent for solid phase extraction (SPE) of vitamin B-12 from cereal food samples. Solid phase extraction parameters, such as the amount of MWCNTs, sample volume, pH, and type and amount of the eluent, were optimized.  相似文献   
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