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51.
The ever‐increasing demand for rechargeable batteries induces significant pressure on the worldwide metal supply, depleting resources and increasing costs and environmental concerns. In this context, developing the chemistry of anion‐inserting electrode organic materials could promote the fabrication of molecular (metal‐free) rechargeable batteries. However, few examples have been reported because little effort has been made to develop such anionic‐ion batteries. Here we show the design of two anionic host electrode materials based on the N‐substituted salts of azaaromatics (zwitterions). A combination of NMR, EDS, FTIR spectroscopies coupled with thermal analyses and single‐crystal XRD allowed a thorough structural and chemical characterization of the compounds. Thanks to a reversible electrochemical activity located at an average potential of 2.2 V vs. Li+/Li, the coupling with dilithium 2,5‐(dianilino)terephthalate (Li2DAnT) as the positive electrode enabled the fabrication of the first all‐organic anionic rechargeable batteries based on crystallized host electrode materials capable of delivering a specific capacity of ≈27 mAh/gelectrodes with a stable cycling over dozens of cycles (≈24 Wh/kgelectrodes).  相似文献   
52.
One of the emerging challenges in the field of 3D characterization of nanoparticles by electron tomography is to avoid degradation and deformation of the samples during the acquisition of a tilt series. In order to reduce the required electron dose, various undersampling approaches have been proposed. These methods include lowering the number of 2D projection images, reducing the probe current during the acquisition, and scanning a smaller number of pixels in the 2D images. A comparison is made between these approaches based on tilt series acquired for a gold nanoparticle.  相似文献   
53.
Nonlinear Dynamics - The fluctuation of ions concentration across the cell membrane of neuron can generate a time varying electromagnetic field. Thus, memristors are used to realize the coupling...  相似文献   
54.

It is well known that clothes used in sporting activity are a barrier for heat exchange between the environment and athlete, which should help in thermoregulation improvement. However, it is difficult to evaluate which top is best for each athlete according to the characteristics of the sport. Researchers have tried to measure the athlete’s temperature distribution during exercise at the base layers of tops with different approaches. The aim of this case study was to investigate the use of thermography for thermo-active base layer evaluation. Six new base layers were measured on one cyclist volunteer during a progressive training on a cycloergometer. As a control condition, the skin temperature of the same volunteer was registered without any layer with the same training. A training protocol was selected approximate to cycling race, which started from the warm-up stage, next the progressive effort until the race finished and at the end “cool-down” stage was over. In order to show which layer provided the strongest and weakest barrier for heat exchange in comparison with environment, the temperature parameters were taken into consideration. The most important parameter in the studies was the temperature difference between the body and the layers, which was changing during the test time. The studies showed a correlation between the ergometer power parameter and the body temperature changes, which has a strong and significant value. Moreover, the mass of every layer was checked before and after the training to evaluate the mass of the sweat exuded during the test. From this data, the layer mass difference parameter was calculated and taken into consideration as a parameter, which may correspond with the mean heart rate value from each training. A high and positive correlation coefficient was obtained between the average heart rate and the mass difference for the base layers. Thermal analysis seems to have a new potential application in the objective assessment of sports clothing and may help in choosing the proper clothes, which could support heat transfer during exercising and protect the body from overheating.

  相似文献   
55.
Ambient‐temperature sodium–sulfur (Na–S) batteries are considered a promising energy storage system due to their high theoretical energy density and low costs. However, great challenges remain in achieving a high rechargeable capacity and long cycle life. Herein we report a stable quasi‐solid‐state Na‐S battery enabled by a poly(S‐pentaerythritol tetraacrylate (PETEA))‐based cathode and a (PETEA‐tris[2‐(acryloyloxy)ethyl] isocyanurate (THEICTA))‐based gel polymer electrolyte. The polymeric sulfur electrode strongly anchors sulfur through chemical binding and inhibits the shuttle effect. Meanwhile, the in situ formed polymer electrolyte with high ionic conductivity and enhanced safety successfully stabilizes the Na anode/electrolyte interface, and simultaneously immobilizes soluble Na polysulfides. The as‐developed quasi‐solid‐state Na‐S cells exhibit a high reversible capacity of 877 mA h g?1 at 0.1 C and an extended cycling stability.  相似文献   
56.
The structures of tripotassium digallium tris(phosphate), K3Ga2(PO4)3, and trisodium gallium bis(phosphate), Na3Ga(PO4)2, have different irregular one‐dimensional alkali ion‐containing channels along the a axis of the orthorhombic and triclinic unit cells, respectively. The anionic subsystems consist of vortex‐linked PO4 tetrahedra and GaO4 tetrahedra or GaO5 trigonal bipyramids in the first and second structure, respectively.  相似文献   
57.
Polysulfonylamines. CLXXXIV. Crystal Structures of Molecular Triphenylphosphanegold(I) Di(4‐X‐benzenesulfonyl)amides: Isomorphism and Close Packing (X = Me, F, Cl, NO2) vs. Structure‐Determining C–X···Au/O Halogen Bonds (X = Br, I) In order to study the structure‐determining influence that halogen bonding can exert during the course of crystallization, solid‐state structures are compared for two previously reported and four new molecular gold(I) complexes of the type Ph3P–Au–N(SO2–C6H4–4‐X)2, each featuring linear P,N coordination at gold and two phenyl rings with varying p‐substituents X = Me, F, Cl, NO2, Br or I. The compounds were synthesized by reactions of Ph3PAuX (X = Cl or I) with the corresponding silver di(arenesulfonyl)amides, crystallized from dichloromethane, and characterized by low‐temperature X‐ray diffraction. The Me, F, Cl and NO2 congeners are isomorphic and crystallize without solvent inclusion in the chiral orthorhombic space group P212121 (Z′ = 1). These structures are governed by isotropic close packing via three‐dimensional 21 symmetry, incidentally supported by an invariant set of C–H···O=S hydrogen bonds, CH/π interactions and π/π stackings of aromatic rings; in particular, the hard halogen atoms of the fluoro and the chloro homologues are not involved in X···Au, X···O or X···X interactions. The higher homologues, with soft halogen atoms, were obtained as a dichloromethane hemisolvate for X = Br and a corresponding monosolvate for X = I, each triclinic in the centrosymmetric space group (Z′ = 1). Here, the primary structural effect is implemented by infinite chains in which translation‐related molecules are connected for the bromo compound by a bifurcated Au···Br(2)···O=S interaction, for the iodo congener by an equivalent Au···I(2)···O=S interaction and a short halogen bond C–I(1)···O=S. The latter bond is stronger than a similar C–Br···O=S interaction and induces a conformational adjustment of the (CSO2)2N group from the normal twofold symmetry in the bromo compound to an energetically unfavourable asymmetric form in the iodo homologue. In both cases, pairs of antiparallel molecular catemers are associated into strands via sixfold phenyl embraces, the strands are stacked to form layers, the solvent molecules are intercalated between adjacent layers, and the crystal packings are reinforced by a number of C–H···O=S hydrogen bonds and interactions of aromatic rings.  相似文献   
58.
A novel single lithium‐ion (Li‐ion) conducting polymer electrolyte is presented that is composed of the lithium salt of a polyanion, poly[(4‐styrenesulfonyl)(trifluoromethyl(S‐trifluoromethylsulfonylimino)sulfonyl)imide] (PSsTFSI?), and high‐molecular‐weight poly(ethylene oxide) (PEO). The neat LiPSsTFSI ionomer displays a low glass‐transition temperature (44.3 °C; that is, strongly plasticizing effect). The complex of LiPSsTFSI/PEO exhibits a high Li‐ion transference number (tLi+=0.91) and is thermally stable up to 300 °C. Meanwhile, it exhibits a Li‐ion conductivity as high as 1.35×10?4 S cm?1 at 90 °C, which is comparable to that for the classic ambipolar LiTFSI/PEO SPEs at the same temperature. These outstanding properties of the LiPSsTFSI/PEO blended polymer electrolyte would make it promising as solid polymer electrolytes for Li batteries.  相似文献   
59.
Structures of Ionic Di(arenesulfonyl)amides. 6. Limits to the Formation of Lamellar Metal Di(arenesulfonyl)amides: Three Lithium Complexes and One Cadmium Complex According to low‐temperature X‐ray studies, the new compounds LiN(SO2C6H4‐4‐X)2 · 2 H2O, where X = COOH ( 1 ) or COOMe ( 2 ), LiN(SO2C6H4‐4‐CONH2)2 · 4 H2O ( 3 ), and Cd[N(SO2C6H4‐4‐COOH)2]2 · 8 H2O ( 4 ) crystallize in the triclinic space group P1 ( 1 – 3 : Z′ = 1; 4 : Z′ = 1/2, Cd2+ on an inversion centre) and display almost perfectly folded anions approximating to mirror symmetry. The lithium ions in 1 – 3 have distorted tetrahedral environments respectively set up by two O=S groups drawn from different anions and two water molecules, two O=S groups of a chelating anion and two water molecules, or one O=C group and three water ligands, whereas the cation of 4 is fully hydrated to form an octahedral [Cd(H2O)6]2+ complex. The structure refinements for 3 and 4 were marred by positional disorder of the non‐coordinating N(SO2)2 moieties. Compounds 1 and 4 extend a previously described series of lamellar metal di(arenesulfonyl)amides where the two‐dimensional inorganic component is comprised of cations, N(SO2)2 groups and water molecules and the outer regions are formed by the 4‐substituted phenyl rings. Both crystal packings are governed by self‐assembly of parallel layers through exhaustive hydrogen bonding between carboxylic groups, and there is good evidence that the labile inorganic networks, generated via Li–O and hydrogen bonds in 1 or solely hydrogen bonds in 4 , are efficiently stabilized by the strong cyclic (COOH)2 motifs within the interlayer regions. In the absence of these, the lamellar architecture is seen to collapse in 2 and 3 , where the carboxyl groups are replaced by methoxycarbonyl or carbamoyl functions and the inorganic components are segregated in parallel tunnels pervading the anion lattices.  相似文献   
60.
Metal Salts of Benzene‐1,2‐di(sulfonyl)amine. 4. Hydrophobically Wrapped Two‐Dimensional Polymers: Crystal Structures of the Isostructural Metal Complexes [M{C6H4(SO2)2N}(H2O)] (M = K, Rb) and of the Structurally Related Ammonium Salt [(NH4){C6H4(SO2)2N}(H2O)] The previously unreported compounds KZ · H2O ( 1 ), RbZ · H2O ( 2 ) and NH4Z · H2O ( 3 ), where Z is Ndeprotonated ortho‐benzenedisulfonimide, are examples of layered inorgano‐organic solids, in which the inorganic component is comprised of metal or ammonium cations, N(SO2)2 groups and water molecules and the outer regions are formed by the planar benzo rings of the anions. The metal complexes 1 and 2 were found to be strictly isostructural, whereas 3 is structurally related to them by a non‐crystallographic mirror plane ( 1 – 3 : monoclinic, space group P21/c, Z = 4; single crystal X‐ray diffraction at low temperatures). In each structure, the five‐membered 1,3,2‐dithiazolide heterocycle possesses an envelope conformation, the N atom lying about 40 pm outside the mean plane of the S–C–C–S moiety. The metal complexes feature two‐dimensional coordination networks interwoven with O–H…O hydrogen bonds originating from the water molecules. The metal centres adopt an irregular nonacoordination formed by five sulfonyl O atoms, two N atoms and two μ2‐bridging water molecules; each M+ is connected to four different anions. When NH4+ is substituted for M+, the metal–ligand bonds are replaced by N+–H…O hydrogen bonds, but the general topology of the lamella is not affected. In the three structures, the lipophilic benzo groups protrude obliquely from the surfaces of the polar lamellae and display marked interlocking between adjacent layers.  相似文献   
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