Molecules of siloles are almost non‐fluorescent but their nanoaggregates are highly emissive, exhibiting aggregation‐induced emission (AIE). The AIE‐active aggregates are cytocompatible with living cells, stain cytoplasms of HeLa cells indelibly without contaminating another type of cell line in a co‐culture system, and remain visible for a long period of time.

In the present work, we demonstrate crystallographically textured n-type BiTeSe nanomaterials with exceptional thermoelectric figures of merit produced by consolidating disk-shaped BiTeSe colloidal nanocrystals (NCs). Crystallographic texture was achieved by hot pressing the asymmetric NCs in the presence of an excess of tellurium. During the hot press, tellurium acted both as lubricant to facilitate the rotation of NCs lying close to normal to the pressure axis and as solvent to dissolve the NCs approximately aligned with the pressing direction, which afterward recrystallize with a preferential orientation. NC-based BiTeSe nanomaterials showed very high electrical conductivities associated with large charge carrier concentrations, n. We hypothesize that such large n resulted from the presence of an excess of tellurium during processing, which introduced a high density of donor Te antisites. Additionally, the presence in between grains of traces of elemental Te, a narrow band gap semiconductor with a work function well below BiTeSe , might further contribute to increase n through spillover of electrons, while at the same time blocking phonon propagation and hole transport through the nanomaterial. NC-based BiTeSe nanomaterials were characterized by very low thermal conductivities in the pressing direction, which resulted in ZT values up to 1.31 at 438 K in this direction. This corresponds to a ca. 40% ZT enhancement from commercial ingots. Additionally, high ZT values were extended over wider temperature ranges due to reduced bipolar contribution to the Seebeck coefficient and the thermal conductivity. Average ZT values up to 1.15 over a wide temperature range, 320 to 500 K, were measured, which corresponds to a ca. 50% increase over commercial materials in the same temperature range. Contrary to most previous works, highest ZT values were obtained in the pressing direction, corresponding to the c crystallographic axis, due to the predominance of the thermal conductivity reduction over the electrical conductivity difference when comparing the two crystal directions.

A composite polymer electrolyte (CPE) based on garnet Li7La3Zr2O12 (LLZO) nanofiber-incorporated PVDF-HFP is reported.

In chemical product design one tries to find a product which exhibits the desired (target) behavior specified a priori. The identity of the ingredients of chemical-based products maybe unknown at the start, but some of their desired qualities and functions are usually known. A systematic model-based computer-aided methodology for design and verification of a class of chemical-based products (liquid formulations) is presented. This methodology is part of an integrated three-stage approach for design/ verification of liquid formulations where stage-1 generates a list of feasible product candidates and/or verifies a specified set through a sequence of predefined activities (work-flow). Stage-2 and stage-3 (not presented here) deal with the planning and execution of experiments, for product validation. Four case studies have been developed to test the methodology. The computer-aided design (stage-1) of a paint formulation and an insect repellent lotion are presented.

A study of the nature of interstitial flows within trickle-bed reactors is presented. Based on physical concepts, a theory is developed to predict the transition boundaries for various flow regimes for nonfoaming liquids. The effects of factors such as bed porosity, size of monodispersed spherical catalyst particles, interfacial tension, viscosity, density, and the gas and liquid flow rates, on flow transitions are considered. Experimental data in the literature are used to confirm the theory and the agreement is good. K. M. NG Chemical Engineering DepartmentUniversity of Massachusetts Amherst, MA 01003 SCOPEIn the design and scale-up of cocurrent down-flow tricklebed reactors, it is imperative to predict which flow regime to expect for a given reactor system and a specified set of operating conditions, since the flow pattern may significantly affect the reactor performance. The present approach relies heavily on empirical flow maps, a typical example of which is a plot of gas flow rate vs. liquid flow rate, with the observed flow regime indicated on the plot for all flow rate combinations. Although this direct approach provides useful information, there are two major drawbacks. First, most flow maps are derived from pilot-scale reactor data and are valid only within a narrow range of operating conditions, usually moderate temperature and pressure, under which the data are obtained. Second, these flow maps do not demonstrate the interplay of various factors such as wettability, interfacial tension, viscosity, bed porosity, and others, on transitions between flow regimes.To resolve this difficulty it is the objective of this paper to put these flow maps on a theoretical basis by providing analytical predictions of flow regime transitions. Six flow regimes are considered: partial wetting trickle flow, complete wetting trickle flow, pulsing flow, spray flow, and bubble and dispersed bubble flows. CONCLUSIONS AND SIGNIFICANCEA model is developed to predict the flow regime map for a given reactor system and a specific set of operating conditions. It has two major components: a porous medium model for granular beds and physical mechanisms for flow transitions. To generate such a flow map, physical parameters such as packing particle size, bed porosity, pressure, temperature, and others are the only required inputs, a list of which is shown in both Tables 1 and 2. The five transition curves designated by different letters of the alphabet, and the equations for calculating them are summarized below.A. Partial wetting to complete wetting, Eqs. 8 and 9 B. Trickling to pulsing, Eqs. (Figure 7) is also found to be in agreement with experimental data. Based on this model, the flow map for a high-pressure airwater system is calculated (Figure 8). It shows that the flow map for a high-pressure system deviates significantly from that of a low-pressure, pilot-scale unit, from which flow maps are usually generated.Thus, this more rigorous hydrodynamic model of the bed allows a priori prediction of a flow regime map. In addition, ...

Bottom-up approaches for producing bulk nanomaterials have traditionally lacked control over the crystallographic alignment of nanograins. This limitation has prevented nanocrystal-based nanomaterials from achieving optimized performances in numerous applications. Here we demonstrate the production of nanostructured Bi SbTe alloys with controlled stoichiometry and crystallographic texture through proper selection of the starting building blocks and the adjustment of the nanocrystal-to-nanomaterial consolidation process. In particular, we hot pressed disk-shaped Bi SbTe nanocrystals and tellurium nanowires using multiple pressure and release steps at a temperature above the tellurium melting point. We explain the formation of the textured nanomaterials though a solution-reprecipitation mechanism under a uniaxial pressure. Additionally, we further demonstrate these alloys to reach unprecedented thermoelectric figures of merit, up to ZT = 1.96 at 420 K, with an average value of ZT = 1.77 for the record material in the temperature range 320-500 K, thus potentially allowing up to 60% higher energy conversion efficiencies than commercial materials.

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