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1.
Bekzat ABDIKADYR Alp KILI Onur ALEV Serkan BÜYÜKK
SE Zafer Ziya
ZTÜRK 《Turkish Journal of Chemistry》2021,45(2):295
Pristine and WO3 decorated TiO2 nanorods (NRs) were synthesised to investigate n-n-type heterojunction gas sensing properties. TiO2 NRs were fabricated via hydrothermal method on fluorine-doped tin oxide coated glass (FTO) substrates. Then, tungsten was sputtered on the TiO2 NRs and thermally oxidised to obtain WO3 nanoparticles. The heterostructure was characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) spectroscopy. Fabricated sensor devices were exposed to VOCs such as toluene, xylene, acetone and ethanol, and humidity at different operation temperatures. Experimental results demonstrated that the heterostructure has better sensor response toward ethanol at 200 °C. Enhanced sensing properties are attributed to the heterojunction formation by decorating TiO2 NRs with WO3. 相似文献
2.
Ersen G
KTÜRK 《Turkish Journal of Chemistry》2020,44(5):1285
In this study, the catalytic activity and stability of flowerlike hybrid horseradish peroxidase (HRP) nanobiocatalyst (HRP-Cu 2+ ) obtained from Cu 2+ ions and HRP enzyme in the polymerization reaction of guaiacol were analyzed. We demonstrated that HRP-Cu 2+ and hydrogen peroxide (H 2 O 2 ) initiator showed significantly increased catalytic activity and stability on the polymerization of guaiacol compared to that of free HRP enzyme. Poly(guaiacol) was observed with quite high yields (88%) and molecular weights (38,000 g/mol) under pH 7.4 phosphate-buffered saline (PBS) conditions at 60 °C with 5 weight% of HRP-Cu 2+ loading. HRP-Cu 2+ also shows very high thermal stability and works even at 70 °C reaction temperature; free HRP enzyme denatures at that temperature. Furthermore, HRP-Cu 2+ provided considerable repeated use and showed some degree of catalytic activity, even after the fourth recycle, in the polymerization of guaiacol. 相似文献
3.
shak ERK Gzde KILI Elif
ZTÜRK engül Alpay KARAOLU Nurettin YAYLI 《Turkish Journal of Chemistry》2020,44(6):1655
The volatile components of essential oil (EO), SPME, and SPME of solvent extracts ( n -hexane, methanol, and water) obtained from fresh Serapias orientalis subsp. orientalis ( Soo ) were analyzed by GC-FID/MS. EO of Soo gave 11 compounds in the percentage of 99.97%; capronaldehyde (37.01%), 2-( E )-hexenal (23.19%), and n -nonanal (19.05%) were found to be major constituents. SPME GC-FID/MS analyses of fresh plant and solvent extracts of Soo revealed 7, 12, 7, and 4 compounds within the range of 99.7% to 99.9%. Limonene (76.5%, 41.7%, and 61.3%) was the major compound in SPMEs of the n -hexane and methanol extracts. α -Methoxy- p -cresol (52.9%) was the main component in its water extract. The antimicrobial activity of EO and the solvent extracts of Soo were screened against 9microorganisms. EO showed the best activity against Mycobacterium smegmatis , with 79.5 µg/mL MIC value. The n -hexane, methanol, and water extracts were the most active against the Staphylococcus aureus within the range of 81.25–125.0 µg/mL (MIC). IC 50 values for the lipase enzyme inhibitory activity of EO and solvent extracts ( n -hexane, methanol, and water) were determined to be 59.87 µg/mL, 64.03 µg/mL, 101.91 µg/mL, and 121.24 µg/mL, respectively. 相似文献
4.
Induction of decision trees via evolutionary programming 总被引:1,自引:0,他引:1
Decision trees have been used extensively in cheminformatics for modeling various biochemical endpoints including receptor-ligand binding, ADME properties, environmental impact, and toxicity. The traditional approach to inducing decision trees based upon a given training set of data involves recursive partitioning which selects partitioning variables and their values in a greedy manner to optimize a given measure of purity. This methodology has numerous benefits including classifier interpretability and the capability of modeling nonlinear relationships. The greedy nature of induction, however, may fail to elucidate underlying relationships between the data and endpoints. Using evolutionary programming, decision trees are induced which are significantly more accurate than trees induced by recursive partitioning. Furthermore, when assessed on previously unseen data in a 10-fold cross-validated manner, evolutionary programming induced trees exhibit a significantly higher accuracy on previously unseen data. This methodology is compared to single-tree and multiple-tree recursive partitioning in two domains (aerobic biodegradability and hepatotoxicity) and shown to produce less complex classifiers with average increases in predictive accuracy of 5-10% over the traditional method. 相似文献
5.
Background
Pentachloronitrobenzene (PCNB) and hexachlorobenzene (HCB) are highly toxic and widespread in every environmental compartment. Some of metabolic products such as amino/nitro containing chlorinated aromatic compounds can be determined by gas chromatography coupled with electron capture detector (GC-ECD). However, it is difficult to identify some of chlorophenolic and chloroquinolic intermediates produced from PCNB and HCB by the above mentioned technique. Therefore, for analysis of these compounds and their metabolites, we have developed a high performance liquid chromatography (HPLC) based method.Results
The extraction of PCNB and HCB from soil and minimal salt medium was carried out with ethyl acetate and hexane respectively with good recoveries (98% for PCNB and 97% for HCB). The validation of the proposed extraction and HPLC method was done by analysis of PCNB and HCB biodegradation and their metabolites identification from anaerobic enriched soil samples.Conclusion
A rapid, sensitive and simple HPLC based analytical method was developed for the analysis of PCNB, HCB and their possible intermediates. 相似文献6.
We consider the thermoelastic plate under the presence of along range memory. We find uniform rates of decay (in time)of the energy, provided that suitable assumptions on the relaxationfunctions are given. Namely, if the relaxation decays exponentiallythen the first order energy also decays exponentially. Whenthe relaxation g satisfies -c1g(t)1+1/p g'(t) -cog(t)1+1/p; and g,g1-1/p L1 (R) withp > 2 then the energy decays as 1/(1+t)p. A new Liapunov functionalis built for this problem. 相似文献
7.
Anghelescu AV DeLisle RK Lowrie JF Klon AE Xie X Diller DJ 《Journal of chemical information and modeling》2008,48(5):1041-1054
We describe and demonstrate a method for the simultaneous, fully flexible alignment of multiple molecules with a common biological activity. The key aspect of the algorithm is that the alignment problem is first solved in a lower dimensional space, in this case using the one-dimensional representations of the molecules. The three-dimensional alignment is then guided by constraints derived from the one-dimensional alignment. We demonstrate using 10 hERG channel blockers, with a total of 72 rotatable bonds, that the one-dimensional alignment is able to effectively isolate key conserved pharmacophoric features and that these conserved features can effectively guide the three-dimensional alignment. Further using 10 estrogen receptor agonists and 5 estrogen receptor antagonists with publicly available cocrystal structures we show that the method is able to produce superpositions comparable to those derived from crystal structures. Finally, we demonstrate, using examples from peptidic CXCR3 agonists, that the method is able to generate reasonable binding hypotheses. 相似文献
8.
Using integer and noninteger n-Slater type orbitals in single- and double-zeta approximations, the Hartree-Fock-Roothaan calculations were performed for the ground states of first ten cationic members of the isoelectronic series of He atom. All the noninteger parameters and orbital exponents were fully optimized. In the case of noninteger n-Slater type orbitals in double zeta basis sets, the results of calculations obtained are more close to the numerical Hatree-Fock values and the average deviations of our ground state energies do not exceed 2×10-6 hartrees of their numerical results. 相似文献
9.
10.
ÜMMÜHAN OCAK HALIT KANTEKIN YAŞAR GÖK H. BASIR ŞENTÜRK 《Journal of inclusion phenomena and macrocyclic chemistry》2006,55(1-2):87-91
The selective liquid–liquid extraction of various transition metal cations from the aqueous phase to the organic phase was carried out using a 14-membered N2O2S2-macrobicycle. Metal picrates such as Pb2+, Co2+, Zn2+, Ni2+,Cu2+ and Cd2+ were used in this extraction studies. It was found that the ligand showed moderate selectivity towards Pb2+ only among the other metals. The extraction constant (log K
ex) was determined to be 13.8 for Pb2+ complex. 相似文献