Quantification of Charge Transport and Mass Deprivation in Solid Electrolyte Interphase for Kinetically-Stable Low-Temperature Lithium-Ion Batteries.

Graphite (Gr)-based lithium-ion batteries with admirable electrochemical performance below -20 °C are desired but are hindered by sluggish interfacial charge transport and desolvation process. Li salt dissociation via Li+-solvent interaction enables mobile Li+ liberation and contributes to bulk ion transport, while is contradictory to fast interfacial desolvation. Designing kinetically-stable solid electrolyte interphase (SEI) without compromising strong Li+-solvent interaction is expected to compatibly improve interfacial charge transport and desolvation kinetics. However, the relationship between physicochemical features and temperature-dependent kinetics properties of SEI remains vague. Herein, we propose four key thermodynamics parameters of SEI potentially influencing low-temperature electrochemistry, including electron work function, Li+ transfer barrier, surface energy, and desolvation energy. Based on the above parameters, we further define a novel descriptor, separation factor of SEI (SSEI), to quantitatively depict charge (Li+/e-) transport and solvent deprivation processes at Gr/electrolyte interface. A Li3PO4-based, inorganics-enriched SEI derived by Li difluorophosphate (LiDFP) additive exhibits the highest SSEI (4.89×103) to enable efficient Li+ conduction, e- blocking and rapid desolvation, and as a result, much suppressed Li-metal precipitation, electrolyte decomposition and Gr sheets exfoliation, thus improving low-temperature battery performances. Overall, our work originally provides visualized guides to improve low-temperature reaction kinetics/thermodynamics by constructing desirable SEI chemistry.

Preparation of anthracene-based tetraperimidine hexafluorophosphate and selective recognition of chromium(III) ions.

A novel anthracene-based tetraperimidine hexafluorophosphate 3 was prepared, and its structure was determined through X-ray analysis, HRMS as well as 1H and 13C NMR spectroscopy. In the cationic moiety of 3, two (N-ethylperimidinyl-C2H4)2NCH2- arms were attached to the 9- and 10-positions of anthracene. In addition, compound 3 was used as a chemosensor to research the ability to recognize Cr3+ through fluorescence and UV titrations, HRMS, as well as 1H NMR and IR spectroscopy. The results indicate that 3 is an effective chemosensor for Cr3+.

Scavenging Radionuclide by Shapeable Porous Materials.

Nuclear energy is a competitive and environmentally friendly low-carbon energy source. It is seen as an important avenue for satisfying energy demands, responding to the energy crisis, and mitigating global climate change. However, much attention has been paid to achieving the effective treatment of radionuclide ions produced in nuclear waste. Initially, advanced adsorbents were mainly available in powder form, which meant that additional purification processes were usually required for separation and recovery in industrial applications. Therefore, to meet the practical requirements of industrial applications, materials need to be molded and processed into forms such as beads, membranes, gels, and resins. Here, we summarize the fabrication of porous materials used for capturing typical radionuclide ions, including UO2 2+, TcO4 -, IO3 -, SeO3 2-, and SeO4 2-.

Preparation of a Tetra-Imidazolium Salt and Sensing for p-Dinitrobenzene.

A macrocyclic tetra-imidazolium salt (2) based on quinoxaline was prepared and characterized. The recognition of 2 to nitro compounds was investigated by fluorescence spectroscopy, 1H NMR titrations, MS, IR spectroscopy, and UV/vis spectroscopy. The results displayed that 2 was able to effectively differentiate p-dinitrobenzene from other nitro compounds via the fluorescence method.

catena-Poly[3,3'-diethyl-1,1'-(propane-1,3-di-yl)di(1H-imidazol-3-ium) [silver(I)-di-µ-iodido-silver(I)-di-µ-iodido]].

The title compound, {(C(13)H(22)N(4))[Ag(2)I(4)]}(n), was prepared by reaction of 1,3-bis-(N-ethyl-imidazolium-1-yl)propane iodide with silver (I) oxide. In the 3,3'-diethyl-1,1'-(propane-1,3-di-yl)di(1H-imidazol-3-ium) cation, the dihedral angle between the imidazole rings is 49.3 (1)°. In the [Ag(2)I(4)](2-) anion, each Ag(I) atom is bonded to three iodide anions, the two Ag(I) atoms and two of the iodides forming Ag(2)I(2) square-planar (r.m.s. deviation = 0.01 Å) units·The remaining two iodides, which are placed on opposite sides of the square, together with their centrosymmetric counterparts, link the square-planar Ag(2)I(2) units into {[Ag(2)I(4)](2-)}(n) polymeric chains via Ag-I bonds.

[Expression of ß-catenin in human pulmonary tissues of smokers with and without chronic obstructive pulmonary disease].

OBJECTIVE: To investigate the expression of ß-catenin in pulmonary tissues of smokers with and without chronic obstructive pulmonary disease (COPD). METHODS: Pulmonary tissues were obtained from patients who had underwent pneumonectomy in Tongji Hospital. The subjects were assigned into non-smokers without COPD (control group), smokers without COPD (smoker group) and smokers with COPD (smoker + COPD group) based on their pulmonary functions and smoking history, with 12 subjects each group. The specimens were obtained as far from the tumor focus (> 5 cm) as possible. Immunofluorescence staining, Western blot and real-time quantitative reverse transcriptase polymerase chain reaction (RT-PCR) were used to investigate the expression and localization of ß-catenin in pulmonary tissues. Numerical data were expressed as the mean ± standard deviation, and were assessed for significance by one-way analysis of variance followed by a Student-Newman-Keuls test for multiple comparisons. The difference of enumeration data was detected by Chi-Square test. Relationship was estimated by Pearson correlation. RESULTS: Immunofluorescence analysis revealed that ß-catenin mainly expressed in the cell membrane of epithelial cells. There was also a positive expression in the cytoplasm and the nuclei of the epithelial cells. The number of alveolar epithelial cells with ß-catenin expressed in the cytoplasm and(or) nucleus was (1.2 ± 0.6)/HP in smokers + COPD group. And the protein and mRNA expression of ß-catenin in pulmonary tissues in smokers + COPD group were 0.26 ± 0.11 and 0.351 ± 0.129, respectively, which were significantly less than those of the smoker group and the control group [(5.0 ± 2.5)/HP and (8.4 ± 3.5)/HP, 0.62 ± 0.23 and 1.00 ± 0.50, 0.60 ± 0.14 and 1.03 ± 0.27]. The differences among the 3 groups were significant (F = 12.809 - 38.776, P < 0.05). Correlation analysis between ß-catenin expression and pulmonary function suggested that the protein and mRNA expression of ß-catenin positively related with FEV(1)%pred (P < 0.05) and FEV(1)/FVC (r = 0.402 - 0.558, P < 0.05). CONCLUSION: ß-catenin expression significantly was decreased in smokers with COPD, and ß-catenin level in the lungs was positively correlated with pulmonary function.

Development of a five-stage solid-state linear transformer driver.

In this paper, the development of a five-stage solid-state linear transformer driver (LTD) is described. Each stage consists of eight compact pulse generating modules and a magnetic core. The pulse generating modules contain a multilayer-ceramic-capacitor-based pulse-forming network (PFN) and an insulated-gate bipolar transistor (IGBT) switch array, as well as magnetic switches, which are used to speed up the pulse front. To prevent damage from the reverse voltage to the IGBT switch, a reverse voltage absorption circuit was added to the PFN. For this study, a larger cross-sectional core with improved output characteristics was adopted. The developed five-stage LTD has the advantages of long life, low jitter, fast rising edge, and so on. The device can provide a 35 kV, 119 ns, 4.3 kA square pulse train with a maximum frequency of 50 Hz. On this basis, a 50-stage LTD of output 500 kV, which would serve as a high-power microwave driver source, is under development.

A solid-state pulse generator based on multilayer ceramic capacitors and insulated gate bipolar transistors.

A solid-state pulse-forming network (PFN) module was designed using multilayer ceramic capacitors (MLCCs). In addition, an all-solid-state pulse generator was fabricated with a Blumlein line that consisted of two PFN single lines and an insulated gate bipolar transistor (IGBT) switch array. This generator was integrated on printed circuit boards (PCBs). The stage capacitors of the PFN were composed of MLCCs connected in series and parallel. To obtain a compact structure, folded, copper-clad wires were used as interstage inductors. The copper-clad wires were structurally optimized to reduce coupling between adjacent interstage inductors. A relatively fast rising waveform edge was obtained using an IGBT gate-boosting circuit and magnetic switch technology. A square-wave pulse with a rise time of 27 ns, a voltage of 5 kV, a width of 120 ns, a maximum repetition rate of 100 Hz, and an evaluated lifetime of 109 pulses was obtained on a load of 6.6 Ω. With its compact size, fast rise time, and long lifetime, the fabricated pulse generator can be used as a component in linear transformer drivers or Marx generators.

1-Butyl-3-(1-naphthyl-meth-yl)benzimidazolium hemi{di-µ-iodido-bis-[diiodidomercurate(II)]} dimethyl sulfoxide monosolvate.

In the title compound, (C(22)H(23)N(2))[Hg(2)I(6)](0.5)·(CH(3))(2)SO, the 1-butyl-3-(1-naphthyl-meth-yl)benzimidazolium anion lies across a centre of inversion. The dihedral angle between the benzimidazolium and naphthalene ring systems is 81.9 (3)°. In the crystal structure, π-π stacking inter-actions are observed between the imidazolium ring and the unsubstituted benzene ring of the naphthalene ring system, with a centroid-centroid separation of 3.510 (5) Å. In the centrosymmetric anion, the Hg(II) atoms are in a distorted tetrahedral coordination. The dimethyl sulfoxide solvent mol-ecule is disordered over two sites with occupancies of 0.615 (9) and 0.385 (9).

Bis(1,3-diethyl-benzimidazolium) tetra-bromidomercurate(II).

In the title compound, (C(11)H(15)N(2))(2)[HgBr(4)], the tetra-coordinated Hg(II) center of the complex anion adopts a distorted tetra-hedral geometry [Hg-Br = 2.5755 (8)-2.623 (11) Šand Br-Hg-Br = 103.78 (19)-116.4 (3)°]. One of the Br atoms is disordered over two sites [site-occupancy factors = 0.51 (6) and 0.49 (6)]. The N-C-N angles in the cations are 110.7 (6) and 111.4 (7)°. In the crystal packing, a supra-molecular chain is formed via both weak inter-molecular C-H⋯Br hydrogen bonds and π-π aromatic ring stacking inter-actions [centroid-centroid separation = 3.803 (1) Å].

1-Benzyl-imidazolium hexa-fluoro-phosphate-1-benzyl-imidazole (1/1).

In the title compound, C(10)H(11)N(2) (+)·PF(6) (-)·C(10)H(10)N(2), the H atom involved in protonation is disordered equally between the cation and the neutral mol-ecule. The dihedral angle between the phenyl and imidazole rings is 82.6 (2)°. In the crystal structure, there are head-to-tail π-π stacking inter-actions between imidazole rings; the inter-planar separation is 3.295 (1) Šand the centroid-centroid separation is 3.448 (3) Å. In the centrosymmetric anion, two F atoms are disordered over two positions; the refined site-occupancy factors are 0.855 (11) and 0.145 (11).

NHC Pd(II) and Ag(I) Complexes: Synthesis, Structure, and Catalytic Activity in Three Types of C-C Coupling Reactions.

Four bis-benzimidazolium salts, 1,4-bis[1'-(N-R-benzimidazoliumyl)methyl]-2,3,5,6-tetramethylbenzene 2X- (L 1 H 2 ·(PF 6 ) 2 : R = ethyl, X = PF6; L 2 H 2 ·Br 2 : R = picolyl, X = Br; L 3 H 2 ·Br 2 : R = benzyl, X = Br; and L 4 H 2 ·Br 2 : R = allyl, X = Br), and their three N-heterocyclic carbene (NHC) Pd(II) and Ag(I) complexes, L 1 Pd 2 Cl 4 (1), L 2 Ag 2 Br 2 (2), and L 4 (AgBr) 2 (3), as well as one anionic complex L 3 H 2 ·(Ag 4 Br 8 ) 0.5 (4), have been synthesized and characterized. Complex 1 adopts a funnel-like type of structure, complex 2 adopts a cyclic structure, and complex 3 is an open structure. In the crystal packing of 1-4, one-dimensional polymeric chains and two-dimensional supramolecular layers are formed via intermolecular weak interactions, including hydrogen bonds, π-π interactions, and C-H···π contacts. The catalytic activities of NHC Pd(II) complex 1 in three types of C-C coupling reactions (Suzuki-Miyaura, Heck-Mizoroki, and Sonogashira reactions) were studied. The results show that this catalytic system is efficient for these C-C coupling reactions.

Cobalt(II), copper(II), zinc(II) and cadmium(II) complexes based on dibenzimidazolyl bidentate ligands with alkanyl linkers: crystal structure, weak interactions and conformations.

Eight metal complexes, {[Co(bibim-4)2(H2O)2](NO3)2}n (1), {[Cu(bibim-4)2(NO3)](NO3)}n (2), [Co(bibim-3)(TP)]n (3), [Zn2(bibim-3)]2(OAc)4] (4), [Co(bibim-2)(NO3)2]n (5), [Zn(bibim-4)(NO3)2]n (6), [Zn(bibim-4)(OAc)2]n (7) and [Cd(bibim-4)(NO3)2(DMF)]n (8) (bibim-2 = 1,2-bis(benzimidazol-l-yl)ethane, bibim-3 = 1,3-bis(benzimidazol-l-yl)propane, bibim-4 = 1,4-bis(benzimidazol-l-yl)butane and TP = terephthalate) have been prepared by means of the self-assembly of Co(II), Cu(II), Zn(II) or Cd(II) salts, dibenzimidazolyl bidentate ligands bearing alkanyl linkers and terephthalic acid. These complexes are structurally characterized by X-ray diffraction analyses. In complexes 1 and 2, 2D network layers with macrometallocycles are formed via metal centers and the ligand bibim-4. A 2D network layer with macrometallocycles in 3 is formed via Co(II) centers, the ligand bibim-3 and terephthalate molecules. In complex 4, a 20-membered macrometallocycle is formed by two bibim-3 ligands and two Zn(II) atoms. In complexes 5­8, 1D polymeric chains are formed via metal centers and the bibim-2 or bibim-4 ligands. In the crystal packings of complexes 1­8, 2D supramolecular layers and 3D supramolecular frameworks are formed via intermolecular weak interactions, including π­π interactions and hydrogen bonds. The different types of π­π interactions from the benzimidazole ring as well as the conformations of the ligands and metal complexes are described. Additionally, the fluorescence emission spectra of the ligands and metal complexes are reported.