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991.
Maleic acid, present in the effluent from organic intermediate producing industries, is an industrially important raw material. Its use in manufacture of alkyd and polyester resins, surface coatings, lubricant additives, plasticizers, co-polymers and agricultural chemicals, makes it necessary to explore for best possible techniques to recover it from aqueous solutions. The present work investigates the recovery of maleic acid from aqueous solution at ambient temperature. N–Methyl–n, n–dioctyloctan–1–ammonium chloride, (commercially known as Aliquat 336) is used as an extractant with three different diluents, belonging to different chemical classes: an aromatic hydrocarbon, a ketone, and an acetate. The chemical extraction results are reported in the terms of distribution coefficient, degree of extraction, and loading ratios. The results were modeled by mass action equilibria model as well as differential evolution technique. Differential evolution algorithm has been prepared. The model and experimental observations were compared and fairly good agreement was observed.  相似文献   
992.
993.
Upconversion nanoparticles (UCNPs) convert near‐infrared into visible light at much lower excitation densities than those used in classic two‐photon absorption microscopy. Here, we engineered <50 nm UCNPs for application as efficient lanthanide resonance energy transfer (LRET) donors inside living cells. By optimizing the dopant concentrations and the core–shell structure for higher excitation densities, we observed enhanced UCNP emission as well as strongly increased sensitized acceptor fluorescence. For the application of these UCNPs in complex biological environments, we developed a biocompatible surface coating functionalized with a nanobody recognizing green fluorescent protein (GFP). Thus, rapid and specific targeting to GFP‐tagged fusion proteins in the mitochondrial outer membrane and detection of protein interactions by LRET in living cells was achieved.  相似文献   
994.
The aim of this work is to estimate sums involving P(n), the largest prime factor of an integer \({n \geqq 2}\) under digital constraints \({{f(P(n)) \equiv a}{\rm mod} b}\), for every \({a \in \mathbb{Z}}\) and an integer \({b \geqq 2}\) where f is a strongly q-additive function with integer values (i.e. \({f(aq^j + b) = f(a) + f(b)}\), with \({(a, b, j) \in \mathbb{N}^3}\), \({{0 \leqq b} < q^j}\)). We also estimate the cardinality of the set \({\{{n \leqq x, f(P(n) + c)} \equiv {a {\rm mod} b}, P(n) \equiv l {\rm mod} k\}}\), where \({c \in \mathbb{Z}}\), \({k \geqq 2}\).  相似文献   
995.
Journal of Cluster Science - Herein we report the hydrothermal synthesis, characterization and biological applications of h-MoO3 and silver doped MoO3 nanoparticles (NPs). The phase formations of...  相似文献   
996.
Innovation in electronic devices has created a demand for energy storage systems. Recently, rechargeable Al-ion batteries (AIBs) have received significant attention owing to their high gravimetric capacity and low cost. In this study, the electrochemical performances of pristine, etched, and electropolished Al negative electrodes via surface modification were investigated to determine their efficiency in AIBs. Herein, pristine, etched, and electropolished Al acted as the negative electrodes (anodes), and pure graphite and aluminum chloride (AlCl3)/1-ethyl-3-methylimidazolium chloride ([EMIm]Cl) were used as the positive electrode (cathode) and ionic liquid electrolyte, respectively. This new type of electropolished Al-based battery cell shows good cyclability and high performance compared to pristine and etched Al electrodes. The electropolished Al electrode stabilized at an average capacity of 50 mAh g−1 over 10,000 cycles at an ultrafast current rate of 5,000 mA g−1.  相似文献   
997.
A series of 30 non-covalent imidazo[1,2-a]quinoxaline-based inhibitors of epidermal growth factor receptor (EGFR) were designed and synthesized. EGFR inhibitory assessment (against wild type) data of compounds revealed 6b, 7h, 7j, 9a and 9c as potent EGFRWT inhibitors with IC50 values of 211.22, 222.21, 193.18, 223.32 and 221.53 nM, respectively, which were comparable to erlotinib (221.03 nM), a positive control. Furthermore, compounds exhibited excellent antiproliferative activity when tested against cancer cell lines harboring EGFRWT; A549, a non-small cell lung cancer (NSCLC), HCT-116 (colon), MDA-MB-231 (breast) and gefitinib-resistant NSCLC cell line H1975 harboring EGFRL858R/T790M. In particular, compound 6b demonstrated significant inhibitory potential against gefitinib-resistant H1975 cells (IC50 = 3.65 μM) as compared to gefitinib (IC50 > 20 μM). Moreover, molecular docking disclosed the binding mode of the 6b to the domain of EGFR (wild type and mutant type), indicating the basis of inhibition. Furthermore, its effects on redox modulation, mitochondrial membrane potential, cell cycle analysis and cell death mode in A549 lung cancer cells were also reported.  相似文献   
998.
999.
3,4-Epoxyalcohols undergo regioselective cyclization in the presence of CeCl3·7H2O in ref1uxing acetonitrile to afford tetrahydrofuran derivatives in good yields. On the other hand epoxyalcohols afforded 1-chloro-3-substituted-2-propanols under microwave irradiation using CeCl3·7H2O supported on SiO2 under solvent-free conditions.  相似文献   
1000.
Kim D  Raj A  Zhu L  Masel RI  Shannon MA 《Lab on a chip》2008,8(4):625-628
We propose a new type of micro/nano fluidic mixer based on non-equilibrium electrokinetics and demonstrate its mixing performance. We fabricate the device with two-step reactive ion etching, one for nanochannels and one for microchannels. Mixing is achieved by strong vortex structures formed near the micro/nano channel interface. We expect the proposed device to be beneficial in the development of micro total analysis systems, since it is simple in its design with minimal fabrication complications.  相似文献   
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