Ljudsko djelovanje u 21. stoljeću, pod utjecajem je 4. industrijske revolucije koja na dnevnoj bazi mijenja način na koji društvo živi, napreduje i egzistira. Neočekivanom pojavom pandemije, kao ...pozitivan odgovor, uslijedila su brojna digitalna rješenja koja su potaknula još veći razvoj i promet, kako web tako i mobilnih aplikacija te ostalih digitalnih rješenja. Glavni cilj ovog rada je istražiti postupke digitalizacije, digitalnih rješenja, tehnologija i aplikacija koje su se koristile tijekom pandemije te ukazati na napredak digitalnih rješenja razvijenih u novim, nepoznatim okolnostima kao i identificirati moguće izazove u njihovom daljnjem razvoju i primjeni te predložiti moguća rješenja. U radu se opisuje uloga tehnologije u olakšavanju svakodnevnih aktivnosti u izvanrednim okolnostima te se identificiraju prednosti i mogući izazovi u primjeni digitalnih rješenja u takvim okolnostima. U tu se svrhu opisuju najutjecajnije web aplikacije i digitalne tehnologije te njihova uloga u osiguranju normalnog tijeka života u izazovnim vremenima.
Human activity in the 21st century is under the influence of the fourth industrial revolution, which is changing the way society lives, develops and exists on a daily basis. The unexpected appearance of the pandemic as a positive reaction was followed by numerous digital solutions that stimulated even greater development and traffic, both web and mobile applications and other digital solutions. The main objective of this paper is to examine digitalization processes, digital solutions, technologies and applications used during the pandemic and to show the progress of digital solutions developed under new, unknown circumstances, as well as to identify possible challenges in their further development and application and to propose possible solutions. The paper describes the role of technology in facilitating everyday activities in exceptional circumstances and highlights the benefits and potential challenges of applying digital solutions in such circumstances. It describes the most influential web applications and digital technologies and their role in ensuring the normal course of life in difficult times.
We investigated ceria nanoparticle/strongly charged polyelectrolyte solution interface on the example of adsorption of a strong polyelectrolyte poly(sodium 4-styrenesulfonate), PSS, on cerium oxide ...nanoparticles to quantitatively characterize the above-mentioned interface. The obtained results could enable a better prediction of nanoparticles behavior in polyelectrolyte solution which could lead to improved applications of ceria nanoparticles. We initially both synthetized and characterized ceria nanoparticles. For the characterization X-ray powder diffraction (XRD), bright-field scanning transmission electron microscopy (TEM), dynamic light scattering (DLS), and electrophoretic mobility measurements were used. Results revealed that nanoparticles are spherical with primary ceria nanoparticles diameter (nanocrystallite size) of approximately 3.5 nm. Results of high-resolution TEM, DLS, and electrophoretic mobility measurements after adsorption of PSS showed that polyelectrolyte-coated nanoparticles were obtained. The comparison of average hydrodynamic diameters of uncoated and PSS-coated ceria nanoparticles leads to the assumed thickness of the polyelectrolyte layer of δ ≈ 9 nm. Finally, for the quantitative interpretation of polyelectrolyte adsorption on ceria nanoparticles, the application of the modified Ohshima model was examined. In that respect, the adsorption parameters such as charge density of the polyelectrolyte layer electrophoretic softness and adsorption density were determined. It was thus shown that Ohshima model could be applied for studying ceria nanoparticle/strongly charged polyelectrolyte solution interface and that the obtained results could serve as a basis for further tailored applications of polyelectrolytes as stabilizing agents for nanoparticles.
The solvent and temperature effects of the hosting of adamantyl mannoside with β‐cyclodextrin in water and structured organic solvents is investigated experimentally and by using molecular dynamics ...simulations. In hydrogen‐bonded solvents, efficient binding is observed, indicating to a solvophobically driven complexation. More information can be found in the Full Paper by R. Ribić, J. Požar et al. on page 5208.
The effects of solvent and temperature on the complexation of adamantyl mannoside with β‐cyclodextrin and 6‐O‐monotosyl‐6‐deoxy‐β‐cyclodextrin were explored experimentally and by means of molecular ...dynamics simulations. Efficient binding was observed only in hydrogen‐bonded solvents, which indicated solvophobically driven complexation. The stability of the inclusion complex was considerably higher in aqueous media. A pronounced temperature dependence of ΔrH○ and ΔrS○, resulting in perfect enthalpy–entropy compensation, was observed in water. The complexation thermodynamics was in line with classical rationale for the hydrophobic effect at lower temperatures and the nonclassical explanation at higher temperatures. This finding linked cyclodextrin complexation thermodynamics with insights regarding the effect of temperature on the hydration water structure. The complexation enthalpies and entropies were weakly dependent on temperature in organic media. The signs of ΔrH○ and ΔrS○ were in accordance with the nonclassical hydrophobic (solvophobic) effect. The structures of the optimized product corresponded to those deduced spectroscopically, and the calculated and experimentally obtained values of ΔrG○ were in very good agreement. This investigation clearly demonstrated that solvophobically driven formation of cyclodextrin complexes could be anticipated in structured solvents in general. However, unlike in water, adamantane and the host cavity behaved solely as structure breakers in the organic media explored so far.
Favorable guest conditions: The effects of solvent and temperature on the complexation of adamantyl mannoside with β‐cyclodextrin and 6‐O‐monotosyl‐6‐deoxy‐β‐cyclodextrin are explored experimentally and by means of molecular dynamics simulations. Efficient binding is observed only in hydrogen‐bonded solvents, which indicates solvophobically driven complexation.
Invited for the cover of this issue is Josip Požar with collaborators from the University of Zagreb. The image depicts the differences in high‐ and low‐temperature water effect on the complexation ...thermodynamics of adamantyl mannoside with β‐cyclodextrin. Read the full text of the article at 10.1002/chem.202000282.
“The results obtained in organic media clearly demonstrated that efficient hosting is not a water‐limited phenomenon.” Read more about the story behind the cover in the Cover Profile and about the research itself on page 5208 ff. (DOI: 10.1002/chem.202000282).
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