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111.
Blended‐salt electrolytes showing synergistic effects have been formulated by simply mixing several lithium salts in an electrolyte. In the burgeoning field of next‐generation lithium batteries, blended‐salt electrolytes have enabled great progress to be made. In this Review, the development of such blended‐salt electrolytes is examined in detail. The reasons for formulating blended‐salt electrolytes for lithium batteries include improvement of thermal stability (safety), inhibition of aluminum‐foil corrosion of the cathode current collector, enhancement of performance over a wide temperature range (or at a high or low temperature), formation of favorable interfacial layers on both electrodes, protection of the lithium metal anode, and attainment of high ionic conductivity. Herein, we highlight key scientific issues related to the formulation of blended‐salt electrolytes for lithium batteries.  相似文献   
112.
Three different kinds of cyclic imides with imido protons are chosen to interact with Hg(II): succinimide, the simplest cyclic imide (five-membered ring); phthalimide (conjugated five-membered ring); and 1,8-naphthalimide (conjugated six-membered ring). Based on the results of MS, (1)H-NMR, XPS, IR spectroscopy and fluorescence response analyses, it is suggested that N-unsubstituted cyclic imides react specifically with Hg(II) and form imide-Hg-imide complexes through an imido proton-metal exchange process. The reaction is reversible and occurs rapidly at moderate to high pH. This discovery expands the comprehension of the specific interaction of Hg(II) with the nucleobase thymine, and may open up new possibilities in designing novel ligands for sensing and removing Hg(II) based on cyclic imides.  相似文献   
113.
A fluorinated tetraphenylbenzidine derivative, N,N′-diphenyl-N,N′-bis(2-fluorophenyl)-1,1′-biphenyl-4,4′-diamine (C36H26F2N2, Mr = 524.59) was synthesized via the palladiumcatalyzed Buchwald-Hartwig reaction of N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine with 2-fluoroiodobenzene (yield: 75%) and structurally characterized. It crystallizes in monoclinic, space group P21/n with a = 9.820(7), b = 14.305(11), c = 10.233(8) , β = 108.973(9)o, V = 1359.3(18) 3, Z = 2, Dc = 1.282 g/cm3, μ(MoKα) = 0.084 mm-1, F(000) = 548, S = 1.018, the final R = 0.0439 and wR = 0.0928. It presents a linear centrosymmetric framework constituted by a linkage of biphenyl as a bridge and two fluorinated diphenylamine moieties. The UV-Vis absorption and fluorescence spectra of the title compound were also investigated. This compound emits intense blue fluorescence with a peak wavelength of 406 nm in film.  相似文献   
114.
A novel lipase gene from Aspergillus fumigatus, afl1-1, was cloned and expressed with a molecular mass of 38 kDa in Escherichia coli for the first time. The recombinant lipase had a preference for short carbon chain p-nitrophenyl esters, especially toward C2 p-nitrophenyl ester and exhibited potent hydrolysis activity that had not been observed. The optimum pH and temperature of this new enzyme were 8.5 and 65 °C, respectively. The recombinant lipase (AFL1-1) is an alkaline enzyme which was stable in the pH range 6.0~8.5 for 16 h (at 4 °C) and at 30~50 °C for 1 h. It is an intracellular enzyme which was purified approximately 8.47-fold with an overall yield of 86.1% by single-step Ni-NTA affinity purification, with a very high specific activity of approximately 1.00?×?10(3) U mg(-1) on a standard substrate of p-nitrophenyl acetate. The Michaelis-Menten kinetic parameters V (max) and K (m) of the lipase were 1.37 mM mg(-1) min(-1) and 14.0 mM, respectively. Ca(2+) and other metal ions could not activate the lipase. According to the homology analysis and site-directed mutagenesis assay, the catalytic triad of the recombinant lipase was identified as Ser-165, Asp-260, and His-290 residues.  相似文献   
115.
为获得可见光响应的储能光催化材料,以离子交换法获得的钨酸溶液与可见光响应光催化剂K4Ce2Ta10-xNbxO30(x=0,5,10)为原料,制备了K4Ce2Ta10-xNbxO30-WO3(x=0,5,10)复合光催化剂。采用XRD,TEM,BET,UV-V is等方法表征了材料的物理化学特性,通过电化学方法和抗菌实验对其储能特性进行表征,分析和研究了K4Ce2Ta10-xNbxO30能带结构对其光催化储能效应的影响及作用机制。研究结果表明,稀土元素Ce贡献于K4Ce2Ta10-xNbxO30能带结构的调变,使得K4Ce2Ta10-xNbxO30-WO3复合光催化材料具有可见光储能特性,在黑暗中也显示出一定的储能抗菌效应。该材料的储能性能受Nb含量和K4Ce2Ta10-xNbxO30的导带位置的影响:随着Nb含量的增加,光生电子还原能力下降,导致储能性能降低。  相似文献   
116.
The impact propylene copolymer(IPC)and isotactic polypropylene(iPP)were separately selected to prepare laminates with high density polyethylene(HDPE)by hot press.The peel forces of IPC/HDPE and i’PP/HDPE laminates were examined,and it was found that the welded joint strength in IPC/HDPE laminate was dramatically higher than that of iPP/HDPE laminate.According to the special microstructure of IPC,the co-crystallization of the ethylene segments in ethylene-propylene block copolymer(EbP)component of IPC and the PE chain in HDPE was proposed to explain the high-strength welding.The DSC results indicated that there indeed existed some interaction between IPC and HDPE,and the crystallizable PE component in IPC could affect the crystallization of HDPE.The scanning electron microscope(SEM) observations of IPC/HDPE blends demonstrated that HDPE tended to stay with the PE-rich EbP chains to form the dispersed phase,indicating the good miscibility between HDPE and EbP components of IPC.According to the above results,the effect of co-crystallization of the PE components of the IPC and HDPE on the high weld strength of IPC/HDPE laminate was confirmed.  相似文献   
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119.
The inhibition of α-glucosidase is a clinical strategy for the treatment of type 2 diabetes mellitus (T2DM), and many natural plant ingredients have been reported to be effective in alleviating hyperglycemia by inhibiting α-glucosidase. In this study, the α-glucosidase inhibitory activity of fisetin extracted from Cotinus coggygria Scop. was evaluated in vitro. The results showed that fisetin exhibited strong inhibitory activity with an IC50 value of 4.099 × 10−4 mM. Enzyme kinetic analysis revealed that fisetin is a non-competitive inhibitor of α-glucosidase, with an inhibition constant value of 0.01065 ± 0.003255 mM. Moreover, fluorescence spectrometric measurements indicated the presence of only one binding site between fisetin and α-glucosidase, with a binding constant (lgKa) of 5.896 L·mol−1. Further molecular docking studies were performed to evaluate the interaction of fisetin with several residues close to the inactive site of α-glucosidase. These studies showed that the structure of the complex was maintained by Pi-Sigma and Pi-Pi stacked interactions. These findings illustrate that fisetin extracted from Cotinus coggygria Scop. is a promising therapeutic agent for the treatment of T2DM.  相似文献   
120.
李姣姣  王志玺 《中国物理 B》2010,19(10):100310-100310
This paper presents monogamy relations for three-qubit quantum states by using convex-roof extended negativity, which inspires studying the difference between the three entanglement measures, concurrence, negativity and convexroof extended negativity. It finds that the convex-roof extended negativity is a stronger entanglement measure than concurrence in multipartite higher-dimensional quantum system.  相似文献   
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