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101.
Keggin type Cobalt and Manganese substituted phosphotungstates were synthesized and characterized by various physicochemical techniques. They were efficiently used for liquid phase non-solvent oxidation of styrene under mild reaction conditions. It was found that the catalytic systems are efficient in achieving higher conversions with high turn over numbers (TONs) and are selective towards benzaldehyde (BA). The complexes behaved as homogeneous catalysts under present oxidation conditions and were efficiently regenerated after a simple workup and reused up to two cycles.  相似文献   
102.
Molecular Diversity - Herein, we identified a potent lead compound RRA2, within a series of 54 derivatives of 1,2,4-triazolethiols (exhibit good potency as an anti-mycobacterial agents) against...  相似文献   
103.
104.

Rapid and onsite detection of nitroaromatic explosive 2,4,6-trinitrotoluene (TNT) is very crucial for the safety and security of human life as well as for the environment. In this present work, we demonstrate the feasibility for employing Folic Acid (FA) as a fluorescent as well as a colorimetric probe for the detection of TNT. This probe was synthesized by a simple one-step process. The developed probe shows an emission maximum at 490 nm upon excitation at 420 nm. On adding TNT, the fluorescence of the FA probe is quenched. Also, it shows a good selectivity towards TNT over other similar organic compounds such as 4-nitrophenol (4-NP), 2,4-dinitrophenol (2,4-DNP) and picric acid (PA). The limit of detection (LoD) of TNT was found to be 1.9398 µM. Colorimetric detection was conducted and paper strip assay was developed for the practical applications.

Graphical Abstract
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105.
Features of the two thin-film techniques, atomic layer deposition (ALD) and molecular layer deposition (MLD), are combined to build up a stable novel inorganic-organic hybrid material of the (-Ti-N-C6H4-O-C6H4-N-)n type, deposited from successive pulses of TiCl4 and 4,4′-oxydianiline precursors. Depositions in the temperature range of 160-230 °C resulted in unstable films, while the films obtained in the temperature range of 250-490 °C were found stable in atmospheric air. The growth rate increased with increasing temperature, from 0.3 Å per cycle at 160 °C to 1.1 Å per cycle at 490 °C.  相似文献   
106.
Thyroid tumors display diverse spectrum of histopathological groups with geographic variation in its prevalence. Influence of iodine deficiency (a major causative factor) in its etiology, prevalence, or aggressiveness is debatable which reflects the existence of various genetic events in pathogenesis. The present study was undertaken to study the role of Microsatellite instability (MSI) or LOH (loss of heterozygosity), an indicator of defective mismatch repair system as a genetic change and to explore it as a prognostic marker in thyroid tumors. Tumor tissues from total thyroidectomy surgical specimens and blood (matched control) of 36 patients from iodine deficient areas (10 benign; 26 malignant) were obtained after their consent. Urinary iodine analysis was done by alkali ash method for which 10 ml of urine was collected from 18 patients before surgery. Genomic DNA, isolated from tumor tissue and blood was amplified by polymerase chain reaction (PCR) using mono and dinucleotide markers - BAT-26, BAT-40, TGF(RII, IGFIIR, hMSH3, BAX, D2S123, D9S283, D9S851 and D18S58. PCR products were analysed on 8% denaturing polyacrylamide gel followed by autoradiography. Of total, 66.6% of tumors [70% (7/10) benign and 65.4% malignant cases (17/26)] showed MSI/LOH. Strong association of MSI/LOH with low iodine (P = 0.01) and with AMES risk groups i.e. age (P = 0.02), tumor size (P = 0.04) and metastases (P = 0.002) in thyroid tumors was observed. This may help in predicting the biological behaviour and strengthening the hypothesis that iodine deficiency has influence on MSI in thyroid tumors. Our results further substantiate the risk group classification and help in deciding the treatment modality in particular patient.  相似文献   
107.
    
We have carried out a combined experimental and theoretical investigation of the structures and properties of a family of cadmium phosphochlorides with varying Cl/Cd and P/Cd ratios, Cd2P3Cl, Cd4P2Cl3, Cd3PCl3, and Cd7P4Cl6. Their optical band gaps are in the visible region and the values are sensitive to the Cl/Cd and P/Cd ratios, leading to an increase and decrease, respectively. First‐principles calculations were used to understand the bonding and electronic structures. All phosphochlorides except Cd2P3Cl possess direct band gaps. The calculated dielectric constants and Born effective charges illustrate the bonding, hybridization, and ionic character in these compounds. The band positions indicate the thermodynamic feasibility to perform water splitting. All systems can be used in the hydrogen evolution reaction (HER), where Cd7P4Cl6 has the highest activity and Cd3PCl3 the lowest. The apparent quantum yield is highest in Cd7P4Cl6 (20.1 %) even without the assistance of a co‐catalyst. The HER activity can be understood on the basis of photoelectrochemical measurements.  相似文献   
108.
    
Developing fluorescent sensor is most advantages in recent years to detect metal ions from biological and environmental systems. Hence, three new donor (carbazole)–acceptor (pyrazine) conjugated polymers (P1–P3) were synthesized by Wittig route. The polymers was structurally confirmed using FTIR, NMR spectroscopy and expressed excellent emission behavior (480–520 nm) towards various polarity of the solvents. Luminescent quantum yield of the polymers P1–P3 were 0.64, 0.69, and 0.72 in chloroform with optical band gap of 2.13, 2.10, and 2.06 eV respectively. Excellent thermal stability with an onset decomposition temperature of P1–P3 was 320, 340, and 200°C under nitrogen atmosphere. Cyclic voltammetry results depicted that the LUMO and HOMO was 3.41 to 3.45 eV and–5.72 to–5.65 eV respectively. Spherical and rod shaped surface morphology of the polymer thin film has been observed from AFM technique. The fluorescence sensitivity of the polymers has been detected towards to Cd2+ ion and its ability of the limit of detection (LOD) was found to be (0.8–1.3) × 10–5 M. This kind of cadmium ion sensing fluorescent polymer probe is highly useful for biomedical applications.  相似文献   
109.
    
Mild steel has been considerably exploited in various manufacturing and commercial fields due to its tremendous mechanical performance. However, mild steel's high susceptibility to corrosion under acidic conditions leads to vast economic losses and environmental consequences. Inhibitors used for steel corrosion in the acidic medium are ordinarily polar heteroaromatic molecules with electronegative atoms. Acridines are one type of inhibitor with several advantages, such as heteroatoms, functional groups and their polarity, double bond conjugation, and importantly efficient and non-hazardous synthetic routes. The polar moieties of such inhibitors are considered to augment their adsorption on steel surface, thus creating a shielding to inhibit steel corrosion. Acridine analogs are N-heterocyclic organic compounds that can be easily produced owing to impeccable inhibition capacity. The current review discusses the chemistry, synthesis, corrosion inhibition mechanism, and properties of acridines and their derivatives.  相似文献   
110.
    
Journal of Solid State Electrochemistry - We have developed a method which is adaptable and straightforward for the production of a negative electrode material based on Si/carbon nanotube (Si/CNTs)...  相似文献   
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