Synthesis of four series of quinoline‐based heterocycles by reacting 2‐chloroquinoline‐3‐carbonitriles with various types of isocyanides

Four distinct sets of functionalized quinolines were synthesized by reacting 2‐chloroquinoline‐3‐carbonitriles with various types of isocyanides under appropriate conditions. The palladium‐catalysed reaction of less hindered aliphatic and aromatic isocyanides with 2‐chloroquinoline‐3‐carbonitriles yielded 2‐alkyl(aryl)‐1‐imino‐1H‐pyrrolo[3,4‐b]quinolin‐3(2H)‐one derivatives; however, the catalysed reaction of more hindered isocyanides such as tert‐butyl isocyanide produced the corresponding 3‐cyanoquinoline‐2‐carboxamides. Interestingly, chloroquinoline‐3‐carbonitriles reacted with ethyl isocyanoacetate in the presence of Cs₂CO₃ to generate imidazo[1,5‐a]quinoline derivatives; notably, tosylmethyl isocyanide under the same conditions formed unprecedented 2‐tosyl‐3‐cyanoquinolines.     

Application of nanostructure ZnLI2 complex in construction of optical pH sensor

This is for the first time that application of complex nanostructure is reported as pH indicator in PVC matrix. This new optical pH sensor was constructed based on incorporation of ZnLI₂ complex nanostructure in PVC matrix. The synthesized nanostructure ZnLI₂ complex was characterized by SEM and XRD technique. The membrane solution was speared on the glass plate to provide thin film and the membrane surface morphology was investigated via field emission scanning microscope (FE‐SEM) technique. Central composite design (CCD) combined with desirability function (DF) was applied to find the best experimental composition of membrane providing the highest absorbance. These conditions were found in correspondence with 3 mg of pH indicator, 3 mg of ionic additive and 1.5 mg/mg of DBP/PVC weight ratio. Under optimum conditions, the proposed pH sensor has two linear working ranges of 4 ‐ 8 at 393 nm (R² = 0.9897) and 5 ‐ 8 (R² = 0.9982) at 570 nm with response time of 4 min. The pK_a of proposed pH optical sensor was calculated through three methods that found to be 5.63. The present optical sensor shows stability after 2 months without any significant divergence in response properties (less than 5% RSD). Furthermore, current pH optode was exhibited good repeatability (RSD = 1.14%) as well as reproducibility (RSD = 4.06%). No significant variation was observed on sensor response with increasing the ionic strength in the range of 0.0–0.5 M of sodium chloride. All above features indicated that the proposed sensor can be successfully used for detection of pH in solutions with different ionic strength.     

An experimental study on free surface vortex dynamics

In the present research, hydrodynamic behavior of free surface vortices including surface displacement of the vortex core as a function of the vortex stability, relationship between the intake hydraulic parameters and vortex strength and characteristics of the vortex vertical stretching as a function of the intake hydraulic parameters were experimentally investigated in a horizontal intake. Relationship between the vortex-induced air and vortex strength was also evaluated and compared with the previous researches. In this regard, by defining a non-dimensional parameter as intake number, relationships between intake hydraulic parameters and other investigated dynamic aspects of free-surface vortices were discussed.     

Experimental study of the subcooled flow boiling heat transfer of magnetic nanofluid in a vertical tube under magnetic field

Journal of Thermal Analysis and Calorimetry - In this study, the subcooled boiling heat transfer of a Fe3O4/water magnetic nanofluid flowing through a vertical tube has been investigated...     

Kaurene as the major constituent of the essential oils of the narcotic plant,Khat (Catha edulis Forsk)

Khat (Catha edulis Forsk) is a narcotic plant which contains significant amounts of amphetamines, like alkaloids. Herein, analysis of the essential oil composition showed that Khat has useful volatile chemicals in addition to its alkaloids. Results indicated that among 35 identified constituents including mono and sesquiterpenes, the diterpene kaurene, comprises the major part of the essential oil, around 50 percent of total. Kaurene is known as a potent biological agent for the treatment of cancer patients. The presence of kaurene at high levels indicates that the essential oil of Catha edulis can potentially be more effectively exploited rather than its narcotic stimulant amphetamine-like alkaloids.     

Mn(Ⅲ)-四芳基卟啉与高碘酸四丁基铵催化羧酸的氧化脱羧:金属、取代基和轴向阴离子配体的影响

锰四芳基卟啉与高碘酸四丁基铵(n-Bu4NIO4)和咪唑(ImH)组合,为羧酸氧化脱羧提供了一个有效的催化剂体系.中位含有吸电子基团和/或大体积芳基的中位-四芳基卟啉使金属卟啉的活性降低.咪唑的存在和金属中心的选择对金属卟啉的催化性能起关键性作用,催化体系中的反离子也有重要影响.Mn(TPP)CN/n-Bu4NIO4/ImH体系的催化活性最好.二苯基乙酸的氧化脱羧可能涉及高价的含氧锰物种与反应物间的相互作用,提出了可能的反应机理.     

The Effect of Solution pH Value on the Morphology of Ceria–Yttria Co Stabilized Zirconia Particles Prepared Using the Polymerizable Complex Method

Ceria–yttria co stabilized zirconia (CYSZ) was synthesized from solutions through the polymerizable complex method. The only difference in the preparation of the CYSZ samples was the pH of the starting solution, which was set at 1, 7 and 12, respectively. Transmission electron microscopy and scanning electron microscopy analysis revealed that the sample with the pH value of 1 had good homogeneity, low agglomeration, and a quasi-spherical shape with the particle size of 41 nm, while by increasing the pH up to 7 and 12, the particles became more disordered and no more in the range of nano sized materials (≤100 nm). Fourier transform infrared spectroscopy was employed to evaluate the bonding characteristics of the obtained gels at different pH values. thermogravimetric analysis, together with differential thermal analysis, was used to study the differences in the properties of dried gels with temperature. Crystallographic structure of the final product was also studied using X-ray diffraction.     

Ion‐Beam Sculpting of Nanowires

Nanomaterials often undergo unusual mechanical deformations compared to their bulk counterparts when irradiated with ion‐beams. This study visualizes and investigates some of the unusual interactions that can occur in nanomaterials during irradiation with medium‐energy ion‐beams using a helium‐ion microscope (HIM). Ion‐beam sculpting of semiconductor nanowires (NWs) with sub‐10 nm features is demonstrated. Moreover, irradiation‐induced growth of NWs at room‐temperature is discovered. The new concept and possible mechanism of irradiation‐induced VLS (vapor–liquid–solid) growth of NWs is introduced. These results are the basis for further fundamental and technological developments toward manipulation and visualization of ion–matter interactions at the nanoscale.