Empowering Zn Electrode Current Capability Along Interfacial Stability by Optimizing Intrinsic Safe Organic Electrolytes

Metallic Zn is one of the most promising anodes, but its practical application has been hindered by dendritic growth and serious interfacial reactions in conventional electrolytes. Herein, ionic liquids are adopted to prepare intrinsically safe electrolytes via combining with TEP or TMP solvents. With this synergy effect, the blends of TEP/TMP with an IL fraction of ≈25 wt% are found to be promising electrolytes, with ionic conductivities comparable to those of standard phosphate-based electrolytes while electrochemical stabilities are considerably improved; over 1000 h at 2.0 mA cm⁻² and ≈350 h at 5.0 mA cm⁻² with a large areal capacity of 10 mAh cm⁻². The use of functionalized IL turns out to be a key factor in enhancing the Zn²⁺ transport due to the interaction of Zn²⁺ ions with IL-zincophilic sites resulting in reduced interfacial resistance between the electrodes and electrolyte upon cycling leading to spongy-like highly porous, homogeneous, and dendrite-free zinc as an anode material.     

Capric acid/intercalated diatomite as form-stable composite phase change material for thermal energy storage

Journal of Thermal Analysis and Calorimetry - Leakage issue and low thermal conductivity largely restrict feasibility of fatty acid in real application of thermal energy storage (TES). In this...     

Collective flow in 2.76 and 5.02 A TeV Pb + Pb collisions

In this paper, we study and predict flow observables in 2.76 and 5.02 A TeV Pb + Pb collisions, using the iEBE-VISHNU hybrid model with TRENTo and AMPT initial conditions and with different forms of the QGP transport coefficients. With properly chosen and tuned parameter sets, our model calculations can nicely describe various flow observables in 2.76 A TeV Pb + Pb collisions, as well as the measured flow harmonics of all charged hadrons in 5.02 A TeV Pb + Pb collisions. We also predict other flow observables, including \(v_n(p_T)\) of identified particles, event-by-event \(v_n\) distributions, event-plane correlations, (normalized) symmetric cumulants, non-linear response coefficients and \(p_T\)-dependent factorization ratios, in 5.02 A TeV Pb + Pb collisions. We find many of these observables to remain approximately the same values as the ones in 2.76 A TeV Pb + Pb collisions. Our theoretical studies and predictions could shed light to the experimental investigations in the near future.     

Boc或Cbz保护的L-脯氨醇衍生物的稳定性

近年来,L-脯氨醇衍生物催化的不对称Michael加成反应已经成为手性催化研究领域的热点.而在L-脯氨醇衍生物的合成中,常常涉及到L-脯氨醇氨基的保护.为此,研究了Boc和Cbz保护的脯氨醇衍生物的稳定性,发现Boc保护的L-脯氨醇在羟基被取代为易离去基团时,就变得不稳定,在67℃就发生分子内环合生成化合物y-丁内酯;而Cbz保护的L-脯氨醇衍生物的稳定性要好得多,在140℃且有三乙胺存在时,才会发生类似的分子内环合反应.     

Piezoelectricity of the ice nanotube with odd side faces

The molecular dynamics (MD) simulations have been utilized to investigate the strain effect on the polarization distribution and piezoelectric coefficient of the ice nanotube (ice-NT) with odd side faces. It is found that the polarization of the system increases under the compressive strain, and decreases with the tensile strain. The piezoelectric coefficient is about 1.3 C/m² for a single 〈5, 0〉 ice-NT with its diameter of 4.34 Å, which is superior to BaTiO₃ nanowire, the ferroelectricity of the latter with the same diameter has been vanished owning to the depolarization effect. We have also considered the axial strain energy under the different strains, and found that most of the strain energy in the compressive process seems larger than that of the stretching case.     

An experimental and CFD study on gas flow field distribution in the growth process of multi‐walled carbon nanotube arrays by thermal chemical vapor deposition

Multi‐walled carbon nanotube arrays (MWCNTAs) were grown by thermal chemical vapor deposition (TCVD) in a horizontal furnace reactor. The scanning electron microscopy (SEM) results show that MWCNTAs grown on the bottom and the central of the quartz tube are different in one experiment. Moreover, the MWCNTAs grown on the central position are more aligned and longer than those on the bottom. A computational fluid dynamics (CFD) model was employed to investigate the gas flow field impact on the MWCNTAs growth. The results show that gas circulations appear after carrier gas and carbon source are injected into the quartz tube. Because of the existence of gas circulations, the gas flow field at the central of the quartz tube is more stable, which is conducive to the growth of MWCNTAs. The CFD simulation results match well with the experimental data.     

钠盐溶液中U(Ⅵ)的电化学电子转移与晶化研究

采用循环伏安法分析钠盐溶液中U(Ⅵ)的电化学行为, 恒电位电化学还原处理U(Ⅵ), 利用交流阻抗谱分析电化学还原反应中的过程动力学特性, 利用X射线衍射、 扫描电子显微镜和电子能谱等方法分析了U(Ⅵ)的电化学晶化. 结果表明, 在钠盐溶液中, U(Ⅵ)可通过电化学反应先还原成低价的U(V)并进一步还原为U(Ⅳ), U(Ⅳ)一步氧化为U(Ⅵ), U(Ⅳ)/U(Ⅵ)之间的电化学转化过程受扩散控制, 且U(Ⅵ)的电化学电子转移易受环境pH值的影响; 恒电位还原4 h时, 溶液中U(Ⅵ)的去除率可达90%, U(Ⅵ)的结晶固化产物主要以固态的(UO₂)₆O₂(OH)₈·6H₂O(水铀矿) 和UO₂的形式附着在工作电极上.     

Ball-milled Ni-Mn-Zn hydroxide for alkaline secondary battery

In our previous study, Mn-substituted nickel hydroxide (Ni_0.8Mn_0.2(OH)₂) was prepared by a simple ball milling method to reduce the cost of nickel hydroxide for alkaline secondary battery, but compared to the Ni(OH)₂ electrode, the Ni_0.8Mn_0.2(OH)₂ one showed an obvious decrease in its discharge potential. In this paper, Zn and Mn co-substituted nickel hydroxide (Ni_0.8Mn_0.2???x Zn _x (OH)₂, x?=?0–0.075) is prepared by ball milling. The results of the cyclic voltammetry (CV) tests illustrate that the co-reduction of Mn(IV) to Mn(III) and NiOOH is observed on the Ni_0.8Mn_0.2???x Zn _x (OH)₂ electrodes, and it has a lower reduction potential than NiOOH. The co-substitution of Zn can effectively increase the co-reduction potential. The ball-milled Ni_0.8Mn_0.15Zn_0.05(OH)₂ electrode has a similar capacity (about 270 mAh g^?1 at a 0.2C rate) and cycling durability to the commercial Ni(OH)₂ with ball milling treatment, but the former has better high-power performance.     

Miscibility and Crystallization Behavior of Poly (Ethylene Terephthalate)/Phosphate Glass Hybrids

Fundamental studies on miscibility and crystallization behavior of poly (ethylene terephthalate) (PET) and inorganic phosphate glass (Pglass) hybrids were conducted. The Flory–Huggins interaction parameter (χ) value of ?0.075 for the PET/Pglass hybrids was obtained using the Nishi–Wang equation, demonstrating that the Pglass and PET components were miscible in the melt state. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed the phase separation occurred during quenching from the melt. The phase boundaries between PET and Pglass were blurred, which indicated partial compatibility of the components in the solid state. Contact angle measurements indicated the interfacial tension of PET/Pglass hybrids was 1.5 mN/m, and the work of adhesion was 78.0 mN/m at 28 °C. Based on the Hoffman–Lauritzen theory, the nucleation constant (K_g) and fold surface free energy (σ_e) of PET/Pglass hybrids were less than those of neat PET.