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191.
Hussain A Gadadhar S Goswami TK Karande AA Chakravarty AR 《Dalton transactions (Cambridge, England : 2003)》2012,41(3):885-895
Lanthanide(III) complexes [Ln(pyphen)(acac)(2)(NO(3))] (1, 2), [Ln(pydppz)(acac)(2)(NO(3))] (3, 4) and [La(pydppz)(anacac)(2)(NO(3))] (5), where Ln is La(III) (in 1, 3, 5) and Gd(III) (in 2, 4), pyphen is 6-(2-pyridyl)-1,10-phenanthroline, pydppz is 6-(2-pyridyl)-dipyrido[3,2-a:2',3'-c]phenazine, anacac is anthracenylacetylacetonate and acac is acetylacetonate, were prepared, characterized and their DNA photocleavage activity and photocytotoxicity studied. The crystal structure of complex 2 displays a GdO(6)N(3) coordination. The pydppz complexes 3-5 show an electronic spectral band at ~390 nm in DMF. The La(III) complexes are diamagnetic, while the Gd(III) complexes are paramagnetic with seven unpaired electrons. The molar conductivity data suggest 1 : 1 electrolytic nature of the complexes in aqueous DMF. They are avid binders to calf thymus DNA giving K(b) in the range of 5.4 × 10(4)-1.2 × 10(6) M(-1). Complexes 3-5 efficiently cleave supercoiled DNA to its nicked circular form in UV-A light of 365 nm via formation of singlet oxygen ((1)O(2)) and hydroxyl radical (HO˙) species. Complexes 3-5 also exhibit significant photocytotoxic effect in HeLa cancer cells giving respective IC(50) value of 0.16(±0.01), 0.15(±0.01) and 0.26±(0.02) μM in UV-A light of 365 nm, while they are less toxic in dark with an IC(50) value of >3 μM. The presence of an additional pyridyl group makes the pydppz complexes more photocytotoxic than their dppz analogues. FACS analysis of the HeLa cells treated with complex 4 shows apoptosis as the major pathway of cell death. Nuclear localization of complex 5 having an anthracenyl moiety as a fluorophore is evidenced from the confocal microscopic studies. 相似文献
192.
Anjali Upadhyay A. K. Singh A. K. Jain Vinod Kumar Gupta Koteswara Rao Bandi 《Electroanalysis》2012,24(7):1630-1638
Preliminary studies on the two Schiff bases N2‐((3H‐indol‐3‐yl)methylene)‐6‐phenyl‐1,3,5‐triazine‐2,4‐diamine (L1) and N2,N4‐bis((3H‐indol‐3‐yl)methylene)‐6‐phenyl‐1,3,5‐triazine‐2,4‐diamine (L2) have shown that they can act as Sm3+ selective electrodes. The performances of a polymeric membrane electrode and a coated graphite electrode based on L2 were compared and the CGE proved to be better, as it shows a low detection limit of 1.8×10?8 mol L?1, a Nernstian slope of 19.6±0.4 mV decade?1 of activity with a response time of 11 s in the pH range of 3.0–9.0. The CGE was used to determine Sm3+ in medicinal plants and soil samples. It was also used to determine fluoride ions in mouthwash samples and in toothpaste. 相似文献
193.
A hybrid approach integrating Affinity Diagram, AHP and fuzzy TOPSIS for sustainable city logistics planning 总被引:1,自引:0,他引:1
City logistics initiatives are steps taken by municipal administrations to ameliorate the condition of goods transport in cities and reduce their negative impacts on city residents and their environment. Examples of city logistics initiatives are urban distribution centers, congestion pricing, delivery timing and access restrictions. In this paper, we present a hybrid approach based on Affinity Diagram, AHP and fuzzy TOPSIS for evaluating city logistics initiatives. Four initiatives namely vehicle sizing restrictions, congestion charging schemes, urban distribution center and access timing restrictions are considered.The proposed approach consists of four steps. The first step involves identification of criteria for assessing performance of city logistics initiatives using Affinity Diagram. The results are four categories of criteria namely technical, social, economical and environmental. In step 2, a decision making committee comprising of representatives of city logistics stakeholders is formed. These stakeholders are shippers, receivers, transport operators, end consumers and public administrators. The committee members weight the selected criteria using AHP. In step 3, the decision makers provide linguistic ratings to the alternatives (city logistics initiatives) to assess their performance against the selected criteria. These linguistic ratings are then aggregated using fuzzy TOPSIS to generate an overall performance score for each alternative. The alternative with the highest score is finally chosen as most suitable city logistics initiative for improving city sustainability. In the fourth step, we perform sensitivity analysis to evaluate the influence of criteria weights on the selection of the best alternative.The proposed approach is novel and can be practically applied for selecting sustainable city logistics initiatives for cities. Another advantage is its ability to generate solutions under limited quantitative information. An empirical application of the proposed approach is provided. 相似文献
194.
Anjali Dhasmana J. P. Barthwal B. R. Pandey B. Ali K. P. Bhargava S. S. Parmar 《Journal of heterocyclic chemistry》1981,18(3):635-637
Eight 1-aryl-3-(2-pyridyl)thiobarbiturates were synthesized and evaluated for their anticonvulsant property and their ability to inhibit succinate dehydrogenase activity of rat brain homogenates. These substituted thiobarbiturates (100 mg./kg., i.p.) provided 20–60% protection against pentylenetetrazol-induced convulsions in albino mice. Low toxicity of these compounds was reflected by their high approximate LD50 values which were found to range from 500–1000 mg./kg. All substituted thiobarbiturates (ImM) inhibited in vitro succinate dehydrogenase activity and the degree of inhibition ranged from 10–72%. 相似文献
195.
Vandana A. Mooss Abhijit A. Bhopale Pravin P. Deshpande Anjali A. Athawale 《Chemical Papers》2017,71(8):1515-1528
In the present work, a set of polyaniline–graphene oxide (PANI–GO) nanocomposites which exhibit superior properties in terms of shelf life, processability and conductivity due to the synergistic effect of GO and PANI, have been synthesized by varying the concentration of highly non-conducting GO with respect to aniline. The obtained materials were characterized by UV–Vis, FTIR, XRD, Raman, TGA as well as FESEM, TEM analysis. The results reveal that nanocomposites show better dispersibility, crystallinity, thermal stability, and conductivity. Further, the synthesized composites have been tested for their anti-corrosion properties. The potentiodynamic results reveal that PANI nanocomposites with 1% GO exhibited long-term anti-corrosion behavior with a corrosion rate of 6.5 × 10?5 mm year?1, which is much lower than its individual components and commercial-grade red oxide. Also, it possesses highest impedance modulus ~33 kΩ cm2 and real impedance ~32 kΩ cm2, maximum coating resistance ~14.81 × 103 Ω cm2 and minimum coating capacitance after 96 h of immersion in 3.5% mass NaCl than those exhibited by all other coated samples. Higher concentration of GO could not retard the corrosion rate confirming that hydrophilicity of GO play an important role in the redox mechanism of PANI. 相似文献
196.
Subhash Chander Seema Lakhanpal Anjali Krishnamurthy Bipin K. Srivastava V. K. Aswal 《Pramana》2004,63(2):345-350
Magnetization measurements are reported on a nano-particle sample of Znsubstituted spinel ferrite Fe2.8Zn0.2O4 in the temperature range 20–300 K. Analysis of small-angle neutron scattering data shows the sample to have a log-normal particle size distribution of median diameter 64.4 Å and standard deviation 0.38. Magnetization evolves over a long period of timet going nearly linearly with logt. Magnetic anisotropy, estimated by fitting M-logt curve, shows many fold increase over that of bulk particle sample. Major enhancement owes to disordered moments in surface layer. In the nano-particle state as well increasing amount of Zn causes anisotropy to decrease. 相似文献
197.
Structural Chemistry - Streptococcus pneumoniae is a major cause of serious infections responsible for mortality worldwide. The ATP-dependent bacterial MurF enzyme catalyzes the addition of... 相似文献