Shape-controllable synthesis of crystalline Ni complex particles via AOT-based microemulsions

This article presents a simple method for the fabrication of shape-controllable Ni complex particles via an AOT-based single microemulsion. In this approach, Ni(2+)/N2H4/EG solution is used as the dispersed phase, and cyclohexane is used as the continuous phase to obtain a microemulsion by the aid of the anionic surfactant AOT. The primary Ni complex particles with diameters of 20-30 nm were first formed in the reverse micelles and then self-organized into spindle-like, ellipse-like, cuboid, and cubic morphologies, depending on the reaction conditions. When aged at 100 degrees C for 24 h, these Ni complex particles changed into crystalline Ni. A possible evolution mechanism of the Ni complex particles with different morphologies is also discussed.     

Suppressing the fragmentation of fragile molecules in helium nanodroplets by coembedding with water: possible role of the electric dipole moment

When fragile molecules such as glycine, polyglycine, alkanes, and alkanethiols are embedded in liquid helium nanodroplets, electron-impact ionization of the beam leads to fragmentation which is as extensive as that of isolated gas-phase molecules. However, it turns out that if a few molecules of water are coembedded with the peptide and alkane chains, their fragmentation is drastically reduced or completely eliminated. On the other hand, the fragmentation of alkanethiols remains unaffected. On the basis of these observations, it is proposed that the fragmentation "buffering" effect may correlate with the magnitude of the impurity's electric dipole moment, which steers the migration of the ionizing He(+) hole in the droplet.     

A novel coupled system of non-local integro-differential equations modelling Young’s modulus evolution,nutrients’ supply and consumption during bone fracture healing

During fracture healing, a series of complex coupled biological and mechanical phenomena occurs. They include: (i) growth and remodelling of bone, whose Young’s modulus varies in space and time; (ii) nutrients’ diffusion and consumption by living cells. In this paper, we newly propose to model these evolution phenomena. The considered features include: (i) a new constitutive equation for growth simulation involving the number of sensor cells; (ii) an improved equation for nutrient concentration accounting for the switch between Michaelis–Menten kinetics and linear consumption regime; (iii) a new constitutive equation for Young’s modulus evolution accounting for its dependence on nutrient concentration and variable number of active cells. The effectiveness of the model and its predictive capability are qualitatively verified by numerical simulations (using COMSOL) describing the healing of bone in the presence of damaged tissue between fractured parts.     

Poly(cyclotriphosphazene-co-phloroglucinol)PCPP as a solid phase extractant for preconcentrative separation of uranium(VI) from aqueous solution

Poly(cyclotriphosphazene-co-phloroglucinol) (PCPP) microspheres, a new solid phase extraction for extracting uranium(VI), synthesized via one-pot precipitation copolymerization. The PCPP microspheres were characterized by FT-IR, SEM/EDS, zeta potential and N₂ adsorption/desorption isotherms. Through the extraction experiment to evaluate the extraction behavior of the PCPP microspheres for uranium(VI). The extractant can achieve the optimal effect under the conditions of contact time with 60 min, pH = 3.5, initial concentration 100 mg L⁻¹ and extractant dosage 0.70 g L⁻¹. The extraction behavior obeyed with the pseudo second-order model and Langmuir isotherm model.

     

Immobilization of ionic liquid with polyelectrolyte as carrier

An all-purpose approach to immobilize ionic liquids onto solid supports is proposed by chemical grafting on a polyelectrolyte carrier.     

Chemisorptive characterization of Mn2+ cation effects on fused iron-catalysts

Volumetric and pulse chemisorptions of carbon monoxide (CO) have been developed to characterize effects of Mn²⁺ cations on an industrial doubly promoted fused iron catalyst. Addition of Mn²⁺ cations induces an increase in Fe dispersity, Fe electronic density and stability of the Mn²⁺-containing iron catalyst, where the same increase is observed by XPS and SEM. These effects explain why the activity of Mn²⁺-containing iron catalysts is improved. Mn²⁺ , . Mn²⁺ Fe, Fe , XPS SEM. . Mn²⁺ .     

An Efficient and General Method for Formylation of Aryl Bromides with CO2 and Poly(methylhydrosiloxane)

The formylation of aryl halides with CO₂ to generate aryl aldehydes is challenging. Herein, we report a novel synthesis of aryl aldehydes by formylation of aryl bromides with CO₂ and a waste silane, poly(methylhydrosiloxane) (PMHS). It has been discovered that a simple combination of 1,3‐bis(diphenyphosphino)propane (DPPP)‐chelated Pd catalyst, Pd(DPPP)Cl₂, with 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) is able to effectively catalyze the reaction, leading to aryl aldehydes in moderate to excellent yields, and without any by‐products in most cases. Moreover, this route could be extended to the formylation of aryl iodides with high efficiency. This approach is simple, less costly, and environmentally friendly, and also widens the applications of CO₂ to form value‐added chemicals by the construction of new C?C bonds.