Lithium-metal anodes are recognized as the most promising next-generation anodes for high-energy-storage batteries.H owever,l ithium dendrites lead to irreversible capacity decayi nl ithium-metal batteries (LMBs). Besides, the strict assembly-environment conditions of LMBs are regarded as ac hallenge for practical applications.I nt his study,aworkable lithium-metal anode with an artificial hybrid layer composed of ap olymer and an alloy was designed and prepared by as imple chemical-modification strategy.T reated lithium anodes remained dendrite-free for over 1000 hinaLi-Li symmetric cell and exhibited outstanding cycle performance in high-areal-loading Li-S and Li-LiFePO 4 full cells.M oreover,t he treated lithium showed improved moisture stability that benefits from the hydrophobicity of the polymer,t hus retaining good electrochemical performance after exposure to humid air.

MXenes are very promising emerging materials for diverse applications because of their outstanding properties. However, the effect of MXene on cell growth and differentiation had barely been studied. Here, we fabricated titanium carbide (Ti3C2) MXene composite nanofibers as smart biomaterials for cell culture and tissue engineering. The composite nanofibers were fabricated by electrospinning and doping and displayed excellent hydrophilicity because of a large number of introduced functional hydrophilic groups. The nanosurface and functional groups of MXene composite nanofibers provide a good microenvironment for cellular growth. Bone marrow-derived mesenchymal stem cells (BMSCs) were applied to assess their biochemical properties. The cell test outcome demonstrated that the obtained MXene composite nanofibers had good biocompatibility and greatly improved cellular activity. These composite nanofibers enhanced BMSC’s differentiation to osteoblasts. The excellent biocompatibility combined with the nanoeffect of MXene suggested that this novel class of biomaterials has the potential to bridge the translational gap in materials sciences and stem cell-based tissue therapies and future multitask biomedical therapies based on MXene’s unique advantages.

The influence of agitation and fluid shear on nucleation of mhydroxybenzoic acid polymorphs from 1-propanol solution has been investigated through 1160 cooling crystallization experiments. The induction time has been measured at different supersaturations and temperatures in two different crystallizer setups: small vials agitated by magnetic stir bars, for which experiments were repeated 40−80 times, and a rotating cylinder apparatus, for which each experiment was repeated five times. The nucleating polymorph has in each case been identified by FTIR spectroscopy. At high thermodynamic driving force for nucleation, only the metastable polymorph (form II) was obtained, while at low driving force both polymorphs were obtained. At equal driving force, a higher temperature resulted in a larger proportion of form I nucleations. The fluid dynamic conditions influence the induction time, as well as the polymorphic outcome. Experiments in small vials show that the agitation rate has a stronger influence on the induction time of form II compared to form I. The fraction of form I nucleations is significantly lower at intermediate agitation rates, coinciding with a reduced induction time of form II. In experiments in the rotating cylinder apparatus, the induction time is found to be inversely correlated to the shear rate. The difference in polymorphic outcome at different driving force is examined in terms of the ratio of the nucleation rates of the two polymorphs, calculated by classical nucleation theory using determined values of the preexponential factor and interfacial energy for each polymorph. A possible mechanism explaining the difference in the influence of fluid dynamics on the nucleation of the two polymorphs is based on differences between the two crystal structures. It is hypothesized that the layered structure of form II is comparatively more sensitive to changes in shear flow conditions than the more isotropic form I structure. ■ INTRODUCTIONA pure substance with the potential to crystallize as more than one crystalline phase with different ordered arrangements of molecules is said to exhibit polymorphism.1 Polymorphs of active pharmaceutical ingredients (APIs) are of great importance to the pharmaceutical industry, since they can exhibit significantly different solubility and dissolution rates, and thereby have different bioavailability. At each given set of conditions, except for transition points, there is one thermodynamically stable polymorph, with the lowest free energy and solubility of all potential polymorphs. Which polymorph will actually crystallize first is subject to both thermodynamic and kinetic factors, however.2 Thermodynamically, the stable polymorph is preferred as it will have a higher driving force for nucleation. The driving force is defined as the difference in chemical potential between the supersaturated and equilibrium states of the compound in solution, and is often approximated as RT ln S, where S is the supersaturation ratio on mole fraction basis. In practice, however, ...

Quaternary tetragonal Cu(2)FeSnS(4) nanocrystals have been synthesized by a simple hot-injection method. Detailed characterizations have been made. A suitable optical band gap of 1.28 ± 0.02 eV and a notable and stable photoelectrochemical response indicate their potential for application in solar cells.

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