排序方式: 共有183条查询结果,搜索用时 31 毫秒
51.
Acid‐catalyzed rearrangement of 6‐phenylbicyclo[3.2.0]heptan‐6‐ol gave 1,1′‐biphenyl and 1,1′‐biphenyl‐carbaldehydes in small amounts as well as the expected rearrangement products. A detailed study of the reaction mechanism revealed that the conversion occurs via an oxidative process through the consecutive formation of cycloheptadienes, cycloheptatrienes, and 1,1′‐biphenyls. The acid‐catalyzed rearrangement of 6‐phenylbicyclo[3.2.0]hept‐2‐en‐6‐ols gave 1‐ and 2‐phenylcycloheptatrienes directly, from which 1,1′‐biphenyl and 1,1′‐biphenyl‐carbaldehydes were obtained by oxidation. 相似文献
52.
This paper provides a new idea for approximating the inventory cost function to be used in a truncated dynamic program for solving the capacitated lot-sizing problem. The proposed method combines dynamic programming with regression, data fitting, and approximation techniques to estimate the inventory cost function at each stage of the dynamic program. The effectiveness of the proposed method is analyzed on various types of the capacitated lot-sizing problem instances with different cost and capacity characteristics. Computational results show that approximation approaches could significantly decrease the computational time required by the dynamic program and the integer program for solving different types of the capacitated lot-sizing problem instances. Furthermore, in most cases, the proposed approximate dynamic programming approaches can accurately capture the optimal solution of the problem with consistent computational performance over different instances. 相似文献
53.
Sema Caglar Esra Dilek Sevim Hamamci Alisir Bulent Caglar 《Journal of Coordination Chemistry》2016,69(16):2482-2492
We report the synthesis of two square-pyramidal copper(II) complexes, [Cu(2,5-pydc)(2-aepy)(H2O)]·H2O, 1, and [Cu(2,5-pydc)(2-ampy)(H2O)]·H2O, 2 (2-aepy = 2-(aminoethyl)pyridine, 2-ampy = 2-(aminomethyl)pyridine, 2,5-pydc = pyridine-2,5-dicarboxylic acid or isocinchomeronic acid). The synthesized complexes have been characterized by X-ray diffraction, FT-IR, elemental, and thermal analysis techniques. The crystal structure of 1 was established by X-ray analysis. Powder X-ray diffraction analysis showed that the complexes are pure. The inhibition of human serum paraoxonase 1 (PON 1, EC 3.1.8.1) enzyme with these complexes were investigated. We used diethyl 4-nitrophenyl phosphate as a substrate to measure the paraoxonase activity of PON 1 enzyme spectrophotometrically. Complexes 1 and 2 decreased the in vitro PON 1 activity with different inhibition mechanisms. Complexes 1 and 2 inhibited paraoxonase activity of this enzyme as competitively and noncompetitively, respectively. 相似文献
54.
Synthesis of Some Novel Norbornene‐Fused Pyridazines as Potent Inhibitors of Carbonic Anhydrase and Acetylcholinesterase
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Ramazan Kocak Esra Turan Akın Pınar Kalın Oktay Talaz Nurullah Saracoglu Arif Dastan Ilhami Gülcin Serdar Durdagi 《Journal of heterocyclic chemistry》2016,53(6):2049-2056
The reaction of benzocyclic norbornene derivatives with tetrazines provided the 1,3‐dihydropyridazine derivatives as a single product. The dihydropyridazine derivatives have been dehydrogenated with phenyliodine bis(trifluoroacetate) to yield the corresponding pyridazines in a high yield. Two stable diazines, primary product of corresponding 1,4‐dihydropyridazine, were also isolated. Structures were then determined by 1H‐NMR, and 13C‐NMR beside to elemental analyses. The novel pyridazine derivatives ( 8 , 9 ) efficiently inhibited the cytosolic human carbonic anhydrase isoenzymes I and II (hCA I and II). In addition, these novel pyridazine derivatives ( 8 , 9 ) were evaluated for their in vitro acetylcholinesterase inhibitory activity. Ligand–receptor interactions are tested using molecular docking simulations. Obtained docking scores are in good agreement with in vitro results. 相似文献
55.
Sema Caglar Esra Dilek Bulent Caglar Ekrem Adiguzel Ersin Temel Orhan Buyukgungor 《Journal of Coordination Chemistry》2016,69(22):3321-3335
Four new neutral diclofenac-based complexes, [Co(dicl)2(2-pyet)2] 1, [Ni(dicl)2(2-pyet)2] 2, [Cu2(dicl)2(2-pyet)2] 3, and [Cu2(dicl)2(2-pypr)2] 4 have been synthesized and characterized by elemental analysis, FT-IR, thermal analysis. Complexes 1, 3, and 4 have also been characterized by X-ray single-crystal structural analysis. The compounds of Co(II) and Ni(II) have octahedral geometry with two diclofenac and two 2-pyridineethanol ligands in the coordination sphere. The compounds of Cu(II) have square-pyramidal geometry and Cu(II) ions are linked via oxygens to the bridging 2-pyridineethanol or 2-pyridinepropanol ligands. The Δν values acquired by FT-IR are in agreement with the single XRD data. Studies on the thermal properties are reported and the complexes are stable to 196, 216, 215, and 201 °C in air, respectively. Two dinuclear Cu(II) complexes have demonstrated catalytic activity on oxidation of 3,5-di-tert-butylcatechol to 3,5-di-tert-butylquinone showing saturation kinetics at high substrate concentrations. The diclofenac complexes are investigated as inhibitors of the human cytosolic isoforms hCA I and II. The complexes are good as hCA I inhibitors (Kis of 1.52–55.06 μM) but only moderately efficient as hCA II inhibitors (Kis of 0.23–5.61 μM). 相似文献
56.
The presence of antibiotic residues in the aquatic environment poses a potential risk to living organisms due to the development of antibiotic resistance in bacteria. In the present study, the removal of isoniazid by commercial powdered activated carbon was studied in aqueous solutions. The adsorption experiments were done as a function of time, concentration, temperature, and pH in order to understand the adsorption mechanism. The Langmuir and the Freundlich isotherms were used to model the equilibrium data. The results showed that isoniazid was physisorbed on the surface of the activated carbon by π–π dispersion interactions. 相似文献
57.
In this paper, we investigated the spectrum of the operator \(L(\lambda )\) generated in Hilbert Space of vector-valued functions \(L_{2}(\mathbb {R}_{+},C_{2})\) by the system and the integral boundary condition of the type where \(\lambda \) is a complex parameter, \(q_{i},\,i=1,2\) are complex-valued functions and \(\alpha ,\beta \in \mathbb {C}\). K(x, t) is vector fuction such that \(K(x,t)=(K_{1}(x,t),K_{2}(x,t)),\,K_{i}(x,t)\in L_{1}(0,\infty )\cap L_{2}(0,\lambda ),\,i=1,2\). Under the condition we proved that \(L(\lambda )\) has a finite number of eigenvalues and spectral singularities with finite multiplicities.
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$$\begin{aligned} iy_{1}^{'}(x,\lambda )+q_{1}(x)y_{2}(x,\lambda )&=\lambda y_{1}(x,\lambda )\\ -iy_{2}^{'}(x,\lambda )+q_{2}(x)y_{1}(x,\lambda )&=\lambda y_{2}(x,\lambda ),x\in \mathbb {R}_{+}:=(0,\infty ), \end{aligned}$$
$$\begin{aligned} \int _{0}^{\infty }K(x,t)y(t,\lambda ){\mathrm {dt}}+\alpha y_{2}(0,\lambda )-\beta y_{1}(0,\lambda )=0 \end{aligned}$$
$$\begin{aligned} \left| q_{i}(x)\right| \le ce^{-\varepsilon \sqrt{x}},c>0,\varepsilon >0,i=1,2 \end{aligned}$$
58.
Çiftçi Gönül Yenilmez Şenkuytu Elif İncir Saadet Elif Eçik Esra Tanrıverdi Zorlu Yunus Ölçer Zehra Uludağ Yildiz 《Mikrochimica acta》2017,184(7):2307-2315
Microchimica Acta - This paper describes an amperometric method for studying DNA-drug candidate interactions. It uses an automatted electrochemical biosensor (MiSens®) based on real-time... 相似文献
59.
Investigation of Luminescence Properties of Eu3+, Dy3+ and Gd3+ Doped MgAl2Si2O8 Red‐emitting Phosphors
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Rare‐earth‐doped aluminosilicates of alkaline earth MgAl2Si2O8: Eu3+, Dy3+ and MgAl2Si2O8: Eu3+, Gd3+ were synthesized by the solid state reaction method at 1300 oC. The phosphors were characterized by X‐ray powder diffraction (XRD), photoluminescence (PL), thermoluminescence (TL) and scanning electron microscopy (SEM). X‐ray powder diffraction studies show that the phosphors were crystallized in the triclinic crystal system. The phosphors show characteristic broad band phosphorescence of Eu3+. This broad band phosphorescence has red emission bands in the range of 580–705 nm corresponding to 5D0 → 7Fj (j:0,2,3,4) transitions of Eu3+. 相似文献
60.
Amperometric Lactate Biosensor Based on Carbon Paste Electrode Modified with Benzo[c]cinnoline and Multiwalled Carbon Nanotubes
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Ali Cihan Çelik Funda Öztürk Pınar Esra Erden Ceren Kaçar Esma Kılıç 《Electroanalysis》2015,27(12):2820-2828
Amperometric lactate biosensor based on a carbon paste electrode modified with benzo[c]cinnoline and multiwalled carbon nanotubes is reported. Incorporation of benzo[c]cinnoline acting as a mediator and multiwalled carbon nanotubes providing a conduction pathway to accelerate electron transfer due to their excellent conductivity into carbon paste matrix resulted in a high performance lactate biosensor. The resulting biosensor exhibited a fast response, high selectivity, good repeatability and storage stability. Under the optimal conditions, the enzyme electrode showed the detection limit of 7.0×10?8 M with a linear range of 2.0×10?7 M–1.1×10?4 M. The usefulness of the biosensor was demonstrated in serum samples. 相似文献