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Non-photochemical laser-induced nucleation (NPLIN) in supersaturated potassium bromide (KBr) solutions with the addition of acidic polymers is reported here for the first time. Upon absorbing the incident laser, crystallites are immediately induced along the laser pathway in the solution, eventually growing into needle-shaped crystals of varying sizes. When comparing induction time, nucleation probability, and crystal habits with spontaneous nucleation, the results suggest that NPLIN creates a distinct morphological pathway, transforming cubic crystals into needle-like structures. Additionally, it improves crystallization probability and growth rate. This paper aims to realize control from crystal nucleation to crystal growth by adding acidic polymers to the process of laser-induced nucleation, potentially influencing crystal morphology modification in NPLIN. With 19 wt% acidic polymers added to the solution as additives, control over both crystal growth and morphological modifications was observed: cubic KBr crystals with square patterns were produced through laser irradiation, and there was a varying reduction in both the number and growth rate of the crystals. The influence of acidic polymers on the solution environment was analyzed to determine the reasons for the variations in crystal quantity and growth speed. The underlying mechanisms responsible for the changes in crystal shape were also discussed.

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The performances of reactive adsorbents, H3PO4/C (activated carbon) and H3PO4/A (Amberlyst 35), in removing NH3 from a waste-gas stream were investigated using a breakthrough column. Accelerated aging tests investigated the effects of the water content on the performance of the adsorbents. Results of breakthrough tests show that the adsorption capacity greatly decreased with the drying time of H3PO4/C preparation. Synchrotron XRPD indicated increased amorphous phosphorus species formation with drying time. Nitrogen adsorption-desorption isotherms results further suggested that the evaporation of water accommodated in macropores decreases adsorption capacity besides the formation of the amorphous species. Introducing water moisture to the NH3 stream increases the adsorption capacity concomitant with the conversion of some NH4H2PO4 to (NH4)2HPO4. Due to the larger pore of cylindrical type and more hydrophilic for acidic porous polymer support, as opposed to slit-type for the activated carbon, the adsorption capacity of H3PO4/A is about 3.4 times that of H3PO4/C. XRPD results suggested that NH3 reacts with aqueous H3PO4 to form NH4H2PO4, and no significant macropore-water evaporation was observed when acidic porous polymer support was used, as evidenced by N2 isotherms characterizing used H3PO4/A.

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The paper presents the results of inverse gas chromatographic (IGC) research on two novel polysiloxanes: poly{dimethylsiloxane-co -[4-(2,3-difluoro-4-hydroxyphenoxy)butyl]methylsiloxane} and poly{dimethylsiloxane-co -[4-(4-hydroxyphenoxy)butyl]methylsiloxane}, dubbed PMFOS and PMOS respectively, designed for use as chemosensitive coatings for acoustoelectronic sensors. These materials contain phenolic functional substituents that differ by the presence of fluorine atoms. The materials' solvation properties were identified by IGC with application of an LSER solvation model at temperatures ranging from 40 to 120 °C. In the case of both polysiloxanes, the research revealed that the dominant type of intermolecular interaction was the formation of acidic hydrogen bonds. The material with fluorine-activated hydroxyl groups, PMFOS, is much more acidic and less basic than the other one and thus more interesting. According to LSER, PMFOS exhibits high affinity and selectivity to hydrogen bond bases. In addition, the material retains its properties even at a temperature of 120 °C.

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Barium sulfate (barite) scale poses significant challenges for processes ranging from water treatment to fossil fuel production. Here, we identify alginate (a polysaccharide derived from brown algae) as a potent, "green" alternative to commercial barite demineralizing agents. Unlike conventional treatments of inorganic scales that require caustic conditions, alginate polymers dissolve barite at near-neutral conditions. In this study, we benchmark the demineralizing efficacy of alginate against a commercial dissolver, diethylenetriaminepentaacetic acid (DTPA), using a combination of bulk dissolution assays, scanning probe microscopy, and molecular dynamics simulations. Time-resolved rates of dissolution measured in a microfluidic device show that demineralization is enhanced more than an order of magnitude under flow. In situ atomic force microscopy reveals that alginate and DTPA exhibit distinct mechanisms of surface dissolution; and surprisingly, their binary combination in alkaline media results in a synergistic cooperativity that enhances the overall rate of barite dissolution. These studies collectively demonstrate a unique approach to demineralization using an inexpensive and abundant biopolymer that enables environmentally friendly treatment of inorganic scales.

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A linear hydrogen-bond acidic (HBA) linear functionalized polymer (PLF), was deposited onto a bare surface acoustic wave (SAW) device to fabricate a chemical sensor. Real-time responses of the sensor to a series of compounds including sarin (GB), dimethyl methylphosphonate (DMMP), mustard gas (HD), chloroethyl ethyl sulphide (2-CEES), 1,5-dichloropentane (DCP) and some organic solvents were studied. The results show that the sensor is highly sensitive to GB and DMMP, and has low sensitivity to HD and DCP, as expected. However, the sensor possesses an unexpected high sensitivity toward 2-CEES. This good sensing performance can't be solely or mainly attributed to the dipole-dipole interaction since the sensor is not sensitive to some high polarity solvents. We believe the lone pair electrons around the sulphur atom of 2-CEES provide an electron-rich site, which facilitates the formation of hydrogen bonding between PLF and 2-CEES. On the contrary, the electron cloud on the sulphur atom of the HD molecule is offset or depleted by its two neighbouring strong electron-withdrawing groups, hence, hydrogen bonding can hardly be formed.

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