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101.
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The characteristic absolute efficiency response curves of a high purity germanium detector (HPGe) for different counting geometries have been established in the energy range 50–1500 keV by measuring the absolute efficiencies using both mono-energetic and multi-gamma emitting radionuclide point calibrated sources supplied by IAEA. Several fitting functions proposed in the literature were assessed for interpolation within the intermediate energy range of interest. The values of the function parameters have been determined by using the linear least square methods. The problems associated with the measurements of experimental efficiency data at small source–detector distances and the importance of the correlation matrix in the estimation of precise uncertainties have been shown. It was found that the inclusion of correlation matrices in the propagation of error formulae plays a significant role up to 450 keV gamma-ray energy and results in a drastic reduction of errors associated with the predicted efficiencies. The discrepancy at closer counting geometries in the absence of true gamma-gamma coincidence corrections is found to reach to about 30%.  相似文献   
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Saraca asoca is an IUCN red-listed tree species that extensively famous in the Ayurvedic medicine field. Saraca asoca (Roxb.) de Wilde belongs to the family Fabaceae, has been used to treat various gynecological disorders, bacterial infections, worm infestations, haemmorhagic dysentery, uterine pain, skin diseases, cancer, circulatory, cardiovascular disorders, and many others. All parts of the Saraca asoca have medicinal values. Numerous antioxidant compounds like flavonoids, catechin, beta-sitosterol, lignin glycosides are present in the bark, leaf, and flower of Saraca asoca plant, which help to stabilize free radicals molecules that are associated with the development of cancer conditions. Currently in the cancer research study field new and more effective modes of natural therapies are recently being analyzed. Traditional medicines have been used for their preventative role against various diseases in the human population. Plant based therapy for cancer prevention is becoming more demanding due to its various unique properties such as natural chemical composition, less expensiveness, naturally available., easily orally administrable, significant chemo-protective activities, nontoxic to normal cells in the body, less side effects compared to other synthetic chemotherapeutic drugs. The chemotherapeutic drugs will be harmful to both cancer and normal cells. Additionally, some common side effects or health consequences like vomiting, nausea, bleeding, hair fall, alopecia, hyperuricemia, thrombocytopenia, bone marrow depression, mucositis are very common after chemotherapeutic drug treatment in cancer. This review paper summarizes the evidences which agree with the fact that flavonoids and other phenolic compounds in Saraca asoca plant possess significant antioxidant activity and an efficient chemopreventive characteristic against different types of cancer. This paper reviews the anticancer activities of Saraca asoca bark and flower and discusses the potential preventive roles of phenolic and flavonoids compounds, present in bark and flower of Saraca asoca in the cancer treatment process.  相似文献   
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The computational reckoning of 2-Chloropyridine-4-carboxylic acid (2CP4CA) was accomplished employing DFT/B3LYP with the root set as 6–311++G(d, p). The impact of polar protic solvents which are eco-friendly solvents (water, methanol, ethanol, 1-propanol) on 2CP4CA were analysed. To examine the solvent effect, vibrational investigations and NLO reports of 2CP4CA in dissimilar solvents were executed. Geometrical properties were also established in gas phase for 2CP4CA. Exercising VEDA program, the entire vibrational assignment was accomplished. Donor-acceptor exchanges were ascertained utilizing NBO scrutiny technique. Thermodynamic properties of 2CP4CA were analysed at different temperatures. By applying TD - DFT approach, theoretic UV–Vis absorption spectrum was procured in different solvents. In order to evaluate the complete electron concentration and sensitive spots of 2CP4CA, MEP coupled with FMO analyses were employed. HOMO along with LUMO orbitals and energy band gap were acquired for 2CP4CA employing dissimilar polar protic solvents. Additionally, ELF, LOL and charge transfer studies were also executed. RDG analysis has been exercised for revealing non-covalent interactions.  相似文献   
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The threat of phenol contamination in aquatic ecosystems is significant for the health of the earth's water systems as well as all humans on it. The present study was conducted to synthesize a cost-effective adsorbent (pea shells activated with sulfuric acid, PSASA) from agriculture waste (pea shells) and its use for effective removal of toxic 4-Aminophenol (4-AP). Newly designed PSASA exhibited significant adsorption of 4-AP which was confirmed by SEM, FT-IR, and XRD analysis. Surface topography confirmed high unevenness of the PSASA surface and the macroporous feature of the PSASA was confirmed by BET analysis. . Multiple testing was done to see how various factors affected adsorption such as adsorbent dose, temperature, pH, PZC, the effect of KCl and urea addition and the effect of the initial concentration of 4-AP. A drop in adsorption uptake of 4-AP was observed as the temperature increases from 25 °C to 45 °C. Maximum adsorption uptake (qm) was found to be 106.11 mg/g at an optimum pH of 7.0 and 25 °C. Among various adsorption isotherm models tested, Langmuir Isotherm gave the best explanation with high R2 values of experimental data. The pseudo-first-order model was found to explain the kinetics of adsorption well. The thermodynamic finding confirms the adsorption process was physical and exothermic. The adsorption of 4-AP was primarily governed by electrostatic interaction, hydrogen-bonding and π-π exchange mechanism. Because of the positive outcomes of the present research, we can use the PSASA as a cost-effective adsorbent for removing phenolic compounds.  相似文献   
109.
The kinetics of oxidation of N,N-bis(salicylaldehyde-1,2-diaminoethane) cobalt(II) complex by N-bromosuccinimide (NBS) in aqueous acid and H2O–MeOH solvent mixtures were studied spectrophotometrically over the 20–40 °C range, 0.1–0.5 mol dm?3 ionic strength, 2.2–2.8 pH range and 0–40 wt% MeOH–H2O solvent mixtures for a range of NBS and complex concentrations. The rate shows first-order dependence on both [NBS] and [complex] and decreases with pH over the range studied. The protonated form of N-bromosuccinimide was identified as the main reactive species. An inner-sphere mechanism involving free radicals is proposed.  相似文献   
110.
A novel and highly efficient approach for the synthesis of H2Me2bqb and H2Me2bpb using ionic liquid as an environmentally benign reaction medium has been developed, eliminating the need for the pyridine as a toxic solvent. The Ni(II) complex of the dianionic ligand Me2bqb2−, [Me2bqb2− = 1,2-bis(quinoline-2-carboxamide)-4,5-dimethyl-benzene dianion], has been synthesized and characterized by elemental analyses and spectroscopic methods, and the crystal and molecular structure of [Ni(Me2bqb)] (1), has been determined by X-ray crystallography. The complex exhibits distorted square-planar NiN4 coordination geometry with two short and two long Ni–N bonds (Ni–N ∼1.85 and ∼1.96 Å, respectively). The electrochemical behavior of [Ni(Me2bqb)] (1), has been studied by cyclic voltammetry and compared with the analogous complex, [Ni(Me2bpb)] (2).  相似文献   
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