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71.
We demonstrate mass-producible, mobile, self-loading microcontainers that can be used to encapsulate both non-living and living objects, thus forming three-dimensionally patterned, mobile microwells.  相似文献   
72.
Kingslin Mary Genova  F.  Selvasekarapandian  S.  Vijaya  N.  Sivadevi  S.  Premalatha  M.  Karthikeyan  S. 《Ionics》2017,23(10):2727-2734
Ionics - Blend polymer electrolytes with optimized composition (92.5 PVA:7.5 PAN) doped with lithium triflate (LiCF3SO3) have been prepared in different concentrations by solution casting...  相似文献   
73.
One pot synthesis of three structurally different Ni(II) thiosemicarbazone complexes 1, 2 and 3 were obtained from the reaction between [NiCl(2)(PPh(3))(2)], 1,2-bis(diphenylphosphino)ethane, and [H(2)-(Sal-tsc)]. The obtained products were characterized by various spectral and analytical techniques. From the X-ray crystallographic analysis, an unexpected N-arylation on the coordinated salicylaldehydethiosemicarbazone was found in complex 2. The comparative biological evolutions such as DNA/protein binding, antioxidant, cytotoxicity (MTT, LDH, and NO) and cellular uptake studies have been examined for [Ni(Sal-tsc)(PPh(3))] (1) and [(Ni(Sal-tsc))(2)(μ-dppe)] (3). When comparing the cytotoxicity of the complexes, 1 exhibited higher activity than 2 and 3 and by comparing with standard cis-platin, both of them were found to exhibit better activity under identical conditions.  相似文献   
74.
The ternary lead bismuth magnesium borophosphate glass system (LBMBPE) with molar concentrations of (50-x) PbO-xBi2O3-25MgHPO4-24B2O3-1Er2O3 (x=10, 20, 30 and 40) was prepared using Melt quenching technique. The amorphous nature of these glass samples were confirmed with XRD studies, The spectral data from the optical absorption studies was employed to compute the spectroscopic parameters such as Racah coefficients (E1, E2 and E3), spin-orbit coupling (ξ4f), configuration interaction factor (α) and Judd-Ofelt intensity parameters (Ωλ, λ=2, 4 and 6). The IR spectra exhibit the presence of vibrational modes of phosphates, borate radicals, bismuth, lead and magnesium ions. The Judd-Ofelt parameterization indicates the covalency and vibrationonic frequencies of the ligands with rare earth ions. The radiative parameters such as radiative transition probabilities (A), the total radiative transitional probabilities (AT), radiative life times (τR), branching ratios (β) and absorption cross sections (∑) were computed for certain lasing levels. The effect of compositional changes on the optical band gap is also reported. The glass systems thus developed indicate their potential lasing candidature.  相似文献   
75.
Advances in the field of micro electro mechanical systems and their uses now offer unique opportunities in the design of ultrasensitive analytical tools. The analytical community continues to search for cost-effective, reliable, and even portable analytical techniques that can give reliable and fast response results for a variety of chemicals and biomolecules. Microcantilevers (MCLs) have emerged as a unique platform for label-free chem-sensor or bioassay. Several electronic designs, including piezoresistive, piezoelectric, and capacitive approaches, have been applied to measure the bending or frequency change of the MCLs upon exposure to chemicals. This review summarizes mechanical, fabrication, and electronics approaches to increase the sensitivity of MCL sensors.  相似文献   
76.
Effective atomic numbers (Zeff) of three polymers, an alloy, a compound and an element have been determined for photoelectric process at 59.54 keV from the accurately measured total attenuation coefficients, for γ ray attenuation. Possible conclusions are drawn on electron binding effects and K-edge effects.  相似文献   
77.
Two new flavonoids, 5, 7, 2', 5'-tetramethoxyflavanone (1) and 5-hydroxy-7, 2'-dimethoxyflavone (2), together with two known flavones, skullcapflavone I (3) and echioidin (4) were isolated from the whole plant of Andrographis rothii. The structures of the new compounds were established by extensive one- and two-dimensional (1D- and 2D-) NMR spectral studies.  相似文献   
78.
Russian Journal of General Chemistry - Large-scale enantioselective synthesis of the chiral amine unit of HCV NS5A inhibitor Elbasvir has been accomplished in six steps, with 55% overall yield. The...  相似文献   
79.
Water-dispersible two-dimensional (2D) materials are desirable for diverse applications. Aqueous dispersions make processing safer and greener and enable evaluation of these materials on biological and environmental fronts. To evaluate the effects of 2D materials with biological systems, obtaining dispersions without additives is critical and has been a challenge. Herein, a method was developed for obtaining additive-free aqueous dispersions of 2D materials like transition metal dichalcogenides and hexagonal boron nitride (h-BN). The nanosheet dispersions were investigated through spectroscopic and microscopic methods, along with the role of size on stability. The aqueous media enabled investigations on cytocompatibility and enzymatic degradation of molybdenum disulphide (MoS2) and h-BN. Cytocompatibility with mixed glial cells was observed up to concentrations of 100 μg mL−1, suggesting their plausible usage in bioelectronics. Besides, biodegradation using human myeloperoxidase (hMPO) mediated catalysis was investigated through Raman spectroscopy and electron microscopy. The findings suggested that additive-free 2H-MoS2 and h-BN were degradable by hMPO, with 2H-phase exhibiting better resistance to degradation than the 1T-phase, while h-BN exhibited slower degradation. The findings pave a path for incorporating 2D materials in the burgeoning field of transient bioelectronics.  相似文献   
80.
Diversely functionalized nitrogen-containing heteroaromatic building blocks, fine chemicals and active pharmaceutical or agrochemical ingredients are conveniently prepared via CN bond formation as the key step. Since beginning of the last decade, there has been a flurry of intense research in forging CN bonds using iron catalysts due to their low cost, high natural abundance and non-toxic nature. The present review offers an overview of CN bond forming reactions involving aryl, allyl, propargyl and unactivated alkyl electrophilic substrates with nitrogen nucleophiles via the regular cross coupling reactions catalyzed by iron. In the miscellaneous section, a set of novel transformations facilitated by iron are included as well.  相似文献   
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