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151.
Nowakowska-Oleksy A Cabaj J Olech K Sołoducho J Roszak S 《Journal of fluorescence》2011,21(4):1625-1633
The benzothiadiazole – arylene alternating conjugated oligomers have been designed and synthesized via Suzuki coupling reaction. The structures and properties of the conjugated oligomers were characterized by 1HNMR, 13CNMR, UV–vis absorption spectroscopy, photoluminescence (PL) spectroscopy. The luminescent measurements demonstrate that polybenzothiadiazoles
are good chromophores able to form thin films by Langmuir-Blodgett (LB) technique, making them suitable for further applications.
Also the electrical properties of obtained films confirm the good potential of these novel aryl-based π-conjugated polymers
for the development of various electrical and electrochemical solid-state devices. 相似文献
152.
Joanna Olczyk Jadwiga Sjka-Ledakowicz Anetta Walawska Anna Antecka Katarzyna Siwiska-Ciesielczyk Jakub Zdarta Teofil Jesionowski 《Molecules (Basel, Switzerland)》2020,25(23)
One of the directions of development in the textiles industry is the search for new technologies for producing modern multifunctional products. New solutions are sought to obtain materials that will protect humans against the harmful effects of the environment, including such factors as the activity of microorganisms and UV radiation. Products made of natural cellulose fibers are often used. In the case of this type of material, it is very important to perform appropriate pretreatment before subsequent technological processes. This treatment has the aim of removing impurities from the surface of the fibers, which results in the improvement of sorption properties and adhesion, leading directly to the better penetration of dyes and chemical modifiers into the structure of the materials. In this work, linen fabrics were subjected to a new, innovative treatment being a combination of bio-pretreatment using laccase from Cerrena unicolor and modification with CuO-SiO2 hybrid oxide microparticles by a dip-coating method. To compare the effect of alkaline or enzymatic pretreatment on the microstructure of the linen woven fabrics, SEM analysis was performed. The new textile products obtained after this combined process exhibit very good antimicrobial activity against Candida albicans, significant antibacterial activity against the Gram-negative Escherichia coli and the Gram-positive Staphylococcus aureus, as well as very good UV protection properties (ultraviolet protection factor (UPF) > 40). These innovative materials can be used especially for clothing or outdoor textiles for which resistance to microorganisms is required, as well as to protect people who are exposed to long-term, harmful effects of UV radiation. 相似文献
153.
Saba Noor Muhammad Waseem Umer Rashid Muhammad Anis-ur-Rehman Wajid Rehman Khalid Mahmood 《中国化学快报》2014,25(5):819-822
We have prepared silica,SiO2coated NiO and NiO coated SiO2by sol-gel method.The physicochemical properties of the desired materials were investigated by surface charge properties,scanning electron microscopy(SEM),energy dispersive X-ray(EDX) spectroscopy,surface area measurements and X-ray diffraction(XRD) analyses.The point of zero charge(PZC) of the solid was determined by the salt addition method.In coated materials,two PZC values were noted representing the surface charge of their counterparts.The SEM image of SiO2coated NiO displays a uniform coating of silica on the surface of NiO whereas in case of NiO coated SiO2,a honeycomb like appearance was observed with highly porous structures.In the diffractograms of NiO,the characteristic peaks were suppressed in NiO coated silica however,no diffraction peak could be seen in SiO2coated NiO.Batch adsorption technique was applied for the removal of Pb2+ions from aqueous solution.The sorption trend for Pb2+ions was observed in the order of NiO coated SiO2〉 SiO2coated NiO 〉 NiO 〉 SiO2.This trend confirms that the coated materials have more sorption capacities than their parent counterparts. 相似文献
154.
Behrooz Maleki Saba Hemmati Reza Tayebee Sirous Salemi Yasaman Farokhzad Mehdi Baghayeri Farrokhzad Mohammadi Zonoz Elahe Akbarzadeh Rohollah Moradi Azam Entezari Mohammad Reza Abdi Samaneh Sedigh Ashrafi Fereshteh Taimazi Majid Hashemi 《Helvetica chimica acta》2013,96(11):2147-2151
A convenient synthesis of sulfonamides and sulfonyl azides from thiols is described. In situ preparation of sulfonyl chlorides from thiols was accomplished by oxidation with chloramine‐T (=N‐chlorotosylamide=N‐chloro‐4‐methylbenzenesulfonamide), tetrabutylammonium chloride (Bu4NCl), and H2O. The sulfonyl chlorides were then further allowed to react with excess amine or NaN3 in the same pot. 相似文献
155.
It is known, since the work of Landor et al, that α-allenic alcohols can be specifically obtained by treating the monotetrahydropyranyl ether of a butyn-1,4-diol with lithium aluminium hydride (1). In this reaction, which can be also realized with another leaving group (halogen, ammonium) (2), the allenic linkage is formed by an SN 2′ process where the nucleophilic hydride is transferred from the initially formed alcoholate (scheme 1). 相似文献
156.
Giorgio Chelucci M. Antonietta Cabras A. Saba 《Journal of heterocyclic chemistry》1994,31(5):1289-1291
A procedure of general application to the synthesis of alkyl-substituted 2-cyano-6-(2-pyridyl)pyridines from alkylpyridines is outlined. 相似文献
157.
158.
Simona Biagini Mariano Casu Adolfo Lai Maura Monduzzi Giuseppe Saba 《Journal of Molecular Liquids》1983,26(1):41-48
A new approach to investigate the conformational properties of the Ni(II) complexes of maleic and succinic acids is reported. The use of C-13 and H-1 paramagnetic shifts and relaxation rates together with an INDO analysis on suitable radical models of the ligands proved a powerful tool in elucidating the conformation of the Ni(II) complex with the partially rigid maleic acid. 相似文献
159.
160.
Zbigniew Florjanczyk Witold Kuran Jadwiga Sitkowska Andrzej Zikowski 《Journal of polymer science. Part A, Polymer chemistry》1987,25(1):343-351
Polymerization of vinyl chloride in the presence of systems containing a transition metal compound/Lewis base and an organoaluminum compound of a different length of carbon chain have been carried out. The influence of the structure and the concentrations of particular components on the polymerization yield and molecular weight of the products has been determined. The polymerization of vinyl chloride proceeds according to the free radical mechanism, and the effectiveness of such types of initiators decreases with an increase in the length of the substituent chain in the organoaluminum chain. When using ethyl derivatives, the maximum degree of vinyl chloride conversion is about 75%, and for polystyryl or polyisoprenylaluminum of an average polymerization degree of 50–100, the conversion did not exceed 0.5%. The maximum polymerization degree of vinyl chloride in block copolymers containing polyisoprenyl or polystyryl units was 90–300. 相似文献