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151.
The preparation of novel 3-, 4-, 6-, and 13-amino-tetradecanoic acid methyl esters (2a–d) obtained by the reduction of 3-, 4-, 6-, and 13-oximino-tetradecanoic acid methyl esters (1a–d), was investigated. Oximino esters were reduced to afford the corresponding amino esters using NaBH4–ZrCl4 reducing system with good yields (58–82%). However, the reduction of oximino esters with LiAlH4 and BH3. Tetrahydrofuran gave the corresponding novel 3-, 4-, 6-, and 13-oximino alcohols (3a–d), and 3-, 4-, 6-, and 13-amino alcohols (4a–d) respectively with good chemical yields. 相似文献
152.
Mustafa Sahin Hatice Korkmaz Nuriye Kocak Ozlem Sahin Serdar Karakurt 《高分子科学杂志,A辑:纯化学与应用化学》2017,54(5):288-300
The metal complexes of Zn(II), Ni(II), Cu(II) and Pb(II) with asymmetrical Schiff bases were synthesized. The asymmetrical Schiff base was obtained through the condensation of 1,2-phenylenediamine, 4-methyl-1,2-phenylenediamine, 2-hydroxy-1-napthaldehyde and biphenyl-4-carbaldehyde. The new Schiff base ligands (L1' and L2') and their metal complexes were characterized by TG/DTG, FT-IR, 1H-NMR, UV–Vis, ESR, powder XRD, elemental analysis, magnetic moment and fluorescence studies. The powder XRD studies indicate that Co(II) and Cu(II) complexes are amorphous, while Ni(II) and Zn(II) complexes are crystalline. The anticarcinogenic effects of L1' and L2' were also investigated against colon (SW-620) and cervical cancer (HeLa) cell lines and compound L2' was found to possess the highest anticarcinogenic potential, with 16.7 µM and 27.5 µM of IC50 values for HeLa and SW620 cells, respectively. 相似文献
153.
A viscoelastic analysis is presented for model tube tooling, draw-down and combined geometry flows encountered in the cable coating industries. The work investigates the development of stress fields and studies the effect of varying entry flow stress boundary conditions. The analysis takes into account tube tooling and draw-down flow sections individually, and in combination. The flow behaviour of cable-coating grade low density polyethylene is studied assuming a viscoelastic, isothermal flow, and employing a Taylor–Petrov–Galerkin finite element scheme with an exponential Phan-Thien–Tanner constitutive model. © 1998 John Wiley & Sons, Ltd. 相似文献
154.
Journal of Thermal Analysis and Calorimetry - Thermodynamic properties and glass transition temperature (Tg) of heat pump dried scallop adductors with (SA-C) and without (SA) sodium alginate... 相似文献
155.
Hatice Busra Tinmaz Irem Arslan Mehmet Atilla Tasdelen 《Journal of polymer science. Part A, Polymer chemistry》2015,53(14):1687-1695
Well‐defined star polymers consisting of tri‐, tetra‐, or octa‐arms have been prepared via coupling‐onto strategy using photoinduced copper(I)‐catalyzed 1,3‐dipolar cycloaddition click reaction. An azide end‐functionalized polystyrene and poly(methyl methacrylate), and an alkyne end‐functionalized poly(ε‐caprolactone) as the integrating arms of the star polymers are prepared by the combination of controlled polymerization and nucleophilic substitution reactions; whereas, multifunctional cores containing either azide or alkyne functionalities were synthesized in quantitatively via etherification and ring‐opening reactions. By using photoinduced copper‐catalyzed azide–alkyne cycloaddition (CuAAC) click reaction, reactive linear polymers are simply attached onto multifunctional cores to form corresponding star polymers via coupling‐onto methodology. The chromatographic, spectroscopic, and thermal analyses have clearly demonstrated that successful star formations can be obtained via photoinduced CuAAC click reaction. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1687–1695 相似文献
156.
Ecem Aydan Alkan Seza Goker Hatice Sarigul Erol Yıldırım Yasemin Arslan Udum Levent Toppare 《Journal of polymer science. Part A, Polymer chemistry》2020,58(7):956-968
Two novel conjugated near-infrared (NIR) absorbing donor–acceptor type copolymers comprising benzodithiophene as the donor and [1,2,5]chalcogenazolo[3,4-f]-benzo[1,2,3]triazole derivatives as the acceptors, spaced with thiophene as the π-bridge, were designed and synthesized via Stille polycondensation reaction. The effect of acceptor strength on optoelectronic properties was targeted and investigated. Branched alkyl chains (the extended 2-octyl-1-dodecyl alkyl chain; C8C12) were introduced to 5H-[1,2,3]triazolo[4′,5′:4,5]benzo[1,2-c][1,2,5]thiadiazole and 5H-[1,2,3]triazolo[4′,5′:4,5]benzo[1,2-c][1,2,5]selenadiazole for enhanced solubility of polymers which ease the processability hence device constructions. The strongly electron-withdrawing units lead to a substantial change in the absorption properties via promotion of the intramolecular charge transfer band alongside the π–π* transition. The resultant soluble polymers were characterized via cyclic voltammetry to determine highest occupied molecular orbital and lowest unoccupied molecular orbital energy levels as −5.00 and −3.92 eV for PSBT and −4.86 and −4.04 eV for PSeBT, respectively. Electronic band gaps of the copolymers were calculated as 1.08 eV for PSBT and 0.82 eV for PSeBT, respectively. NIR absorbing copolymers were used to construct electrochromic devices. 相似文献
157.
Prnová Anna Valúchová Jana Mutlu Nurshen Parchovianský Milan Klement Róbert Plško Alfonz Galusek Dušan 《Journal of Thermal Analysis and Calorimetry》2020,142(1):129-138
Journal of Thermal Analysis and Calorimetry - Yttrium aluminate glasses (76.8 mol% of Al2O3, 23.2 mol% of Y2O3) doped with Er3+ and Nd3+ ions at different concentration levels... 相似文献
158.
用胺甲基树脂与5-氟-2-羟基苯甲醛,5-氟-3-氯-2-羟基苯甲醛,5-氟-3-甲基-2-羟基苯甲醛反应合成了3种新颖的高分子担载席夫碱和它们Cr(Ⅲ)配合物,并用元素分析、磁化率、IR、1HNMR、UV-Vis、TG/DTA对其进行了表征。就一些革兰氏阳性菌(芽孢杆菌属腊状芽孢杆菌(Bacillus cereus sp),单核细胞增生李斯特菌4b(Listeria monocytogenes 4b),藤黄微球菌(Micrococcus luteus),金黄色葡萄球菌(Staphylococcus aureus)表皮葡萄球菌(Staphylococcus epidermis))和革兰氏阴性菌(布鲁氏菌(Brucella abortus),大肠杆菌(Escherichia coli),恶臭假单胞菌SP(Pseudomonas putidasp.),痢疾志贺氏菌10(Shigella dysenteria type 10),伤寒杆菌H(Salmonella typhi H)和酵母菌(念珠菌)(yeast(Candida albicans))用井扩散法对高分子担载席夫碱和它们Cr(Ⅲ)配合物的生物学活性进行了筛选。 相似文献
159.
160.