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Two concomitant polymorphic coordination complexes (dark blue – I and black – II) with the formula (Cu2C44H60N4O4) have been synthesized and characterized crystallographically. Magnetic measurements show the presence of a strong antiferromagnetic interaction and the 2J value corresponds extremely well to the theoretically calculated one, indicating the fact that it follows nicely the magneto-structural relationship. Immobilization of the copper(II) complex 1 on a 2D-hexagonal mesoporous silica showed good catalytic efficiency in the liquid phase partial oxidation of olefins in the presence of TBHP as an oxidant.  相似文献   
73.
This work demonstrates the synthesis and characterization of core‐shell magnetic molecularly imprinted polymers based on surface imprinting using methacryloyl chloride as a functional monomer for the selective extraction of imidacloprid (template) from apple fruit. The characterization analysis results ensured the successful synthesis of the magnetic molecularly imprinted polymers owing to their heterogeneous structure and good magnetic properties. An isothermal binding test was assessed with a pseudo‐second‐order kinetic model, and the kinetic results fit well to the Freundlich isothermal model. The polymers exhibited an adsorption capacity of 5.75 mg/g for the target analyte with a good selective extraction ability. In addition, the polymers can be reused several times without significant performance loss. The molecularly imprinted polymers showed good performance in the analysis of spiked apple sample with a linear range of 0.05–1.0 mg/L, a limit of detection of 0.048 mg/L and a limit of quantification of 0.146 mg/L (S/N = 3/10). The recoveries of the samples were 77.66–96.57% and their respective relative standard deviations were 3.36–0.45%. All the results indicated that the proposed method provided good selective extraction, as qualifying the analytical standards.  相似文献   
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Quantum Hamilton-Jacobi theory and supersymmetric quantum mechanics (SUSYQM) are two parallel methods to determine the spectra of a quantum mechanical systems without solving the Schrödinger equation. It was recently shown that the shape invariance, which is an integrability condition in SUSYQM formalism, can be utilized to develop an iterative algorithm to determine the quantum momentum functions. In this Letter, we show that shape invariance also suffices to determine the eigenvalues in quantum Hamilton-Jacobi theory.  相似文献   
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Natural products represents an important source of new lead compounds in drug discovery research. Several drugs currently used as therapeutic agents have been developed from natural sources; plant sources are specifically important. In the past few decades, pharmaceutical companies demonstrated insignificant attention towards natural product drug discovery, mainly due to its intrinsic complexity. Recently, technological advancements greatly helped to address the challenges and resulted in the revived scientific interest in drug discovery from natural sources. This review provides a comprehensive overview of various approaches used in the selection, authentication, extraction/isolation, biological screening, and analogue development through the application of modern drug-development principles of plant-based natural products. Main focus is given to the bioactivity-guided fractionation approach along with associated challenges and major advancements. A brief outline of historical development in natural product drug discovery and a snapshot of the prominent natural drugs developed in the last few decades are also presented. The researcher’s opinions indicated that an integrated interdisciplinary approach utilizing technological advances is necessary for the successful development of natural products. These involve the application of efficient selection method, well-designed extraction/isolation procedure, advanced structure elucidation techniques, and bioassays with a high-throughput capacity to establish druggability and patentability of phyto-compounds. A number of modern approaches including molecular modeling, virtual screening, natural product library, and database mining are being used for improving natural product drug discovery research. Renewed scientific interest and recent research trends in natural product drug discovery clearly indicated that natural products will play important role in the future development of new therapeutic drugs and it is also anticipated that efficient application of new approaches will further improve the drug discovery campaign.  相似文献   
76.
Production of hydrogen (H2) and oxygen (O2) through electrocatalytic water splitting is one of the sustainable,green and pivotal ways to accomplish the ever-inc...  相似文献   
77.
Nano-bioremediation application is an ecologically and environmentally friendly technique to overcome the catastrophic situation in soil because of petroleum waste contamination. We evaluated the efficiency of oil-degrading bacterial consortium and silver nanoparticles (AgNPs) with or without fertilizer to remediate soils collected from petroleum waste contaminated oil fields. Physicochemical characteristics of control soil and petroleum contaminated soils were assessed. Four oil-degrading strains, namely Bacillus pumilus (KY010576), Exiguobacteriaum aurantiacum (KY010578), Lysinibacillus fusiformis (KY010586), and Pseudomonas putida (KX580766), were selected based on their in vitrohydrocarbon-degrading efficiency. In a lab experiment, contaminated soils were treated alone and with combined amendments of the bacterial consortium, AgNPs, and fertilizers (ammonium nitrate and diammonium phosphate). We detected the degradation rate of total petroleum hydrocarbons (TPHs) of the soil samples with GC-FID at different intervals of the incubation period (0, 5, 20, 60, 240 days). The bacterial population (CFU/g) was also monitored during the entire period of incubation. The results showed that 70% more TPH was degraded with a consortium with their sole application in 20 days of incubation. There was a positive correlation between TPH degradation and the 100-fold increase in bacterial population in contaminated soils. This study revealed that bacterial consortiums alone showed the maximum increase in the degradation of TPHs at 20 days. The application of nanoparticles and fertilizer has non-significant effects on the consortium degradation potential. Moreover, fertilizer alone or in combination with AgNPs and consortium slows the rate of degradation of TPHs over a short period. Still, it subsequently accelerates the rate of degradation of TPHs, and a negligible amount remains at the end of the incubation period.  相似文献   
78.
The main characteristic feature of diabetes mellitus is the disturbance of carbohydrate, lipid, and protein metabolism, which results in insulin insufficiency and can also lead to insulin resistance. Both the acute and chronic diabetic cases are increasing at an exponential rate, which is also flagged by the World Health Organization (WHO) and the International Diabetes Federation (IDF). Treatment of diabetes mellitus with synthetic drugs often fails to provide desired results and limits its use to symptomatic treatment only. This has resulted in the exploration of alternative medicine, of which herbal treatment is gaining popularity these days. Owing to their safety benefits, treatment compliance, and ability to exhibit effects without disturbing internal homeostasis, research in the field of herbal and ayurvedic treatments has gained importance. Medicinal phytoconstituents include micronutrients, amino acids, proteins, mucilage, critical oils, triterpenoids, saponins, carotenoids, alkaloids, flavonoids, phenolic acids, tannins, and coumarins, which play a dynamic function in the prevention and treatment of diabetes mellitus. Alkaloids found in medicinal plants represent an intriguing potential for the inception of novel approaches to diabetes mellitus therapies. Thus, this review article highlights detailed information on alkaloidal phytoconstituents, which includes sources and structures of alkaloids along with the associated mechanism involved in the management of diabetes mellitus. From the available literature and data presented, it can be concluded that these compounds hold tremendous potential for use as monotherapies or in combination with current treatments, which can result in the development of better efficacy and safety profiles.  相似文献   
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