Journal of Physical and Theoretical Chemistry
Volume:17 Issue: 3, Autumn and Winter 2021

Sensor synthesis synthesized PbS functionalized with gelatin quantum dots have been considered as novel drugs sensors due to their ultrafine size, photo-stability and excellent fluorescent properties. In this study, a facile method was developed for the preparation of fluorescent water-soluble PbS quantum dots with gelatin sensor. The fluorescence of the PbS quantum dots sensor functionalized with gelatin synthesis is selectively and sensitively enhanced by addition of the Phenylpropanolamine (PPA) drug-induced aggregation of sensor PbS with gelatin. This finding was further used to design a fluorometric method for the determination of (PPA) drug, The reaction is followed fluoremetrically by measuring the absorbance at 335 nm. 2.5×10-2 molL-1 PbS with gelatin sensor, calibration graph in the rang of 0.05 - 10.0 µg L-1 (PPA) drug. The absorbance is linear from 0.05 up to 100.0 µg L−1 in aqueous solution with repeatability (RSD) of 3.5% at a concentration of 10.0 µg L−1 and a detection limit of 2.2 µg L−1 by the fixed-time method of 60 sec. The relative standard deviation for 10.0 µg L-1 (PPA) drug is %95. The applicability of the method was demonstrated by the determination of the (PPA) drug in urine and blood samples

The applicability of Mn-doped Fe2O4 nanoparticles loaded on activated carbon for removing Phenol from aqueous solutions has been reported. This novel material was characterized by different techniques such as FT-IR, XRD and SEM. The influence of nanoparticle dosage, pH of the sample solution, individual Phenol concentration, contact time between the sample and the adsorbent, temperature, and ionic strength of the sample solution were studied by performing a batch adsorption technique. The maximum removal of 5-25 mg L-1 of individual Phenol from an aqueous sample solution at pH 6.0 for Phenol was achieved within 30 min when an adsorbent amount of 0.1 g was used. It was shown that the adsorption of Phenol follows the Langmuir isotherm model best described the experimental adsorption data with maximum adsorption capacities of 4.27 mg/g. The kinetic data were best described by the pseudo-second order model (R2 = 0.9997) explains equilibrium data. Isotherms had also been used to obtain the thermodynamic parameters such as free energy (ΔG0), enthalpy (ΔH0) and entropy (ΔS0) of adsorption. The negative value of (ΔGo, ΔHo and ΔSo) confirmed the sorption process was endothermic reflects the affinity of Mn-doped Fe2O4 nanoparticles loaded on activated carbon functionalized towards Phenol. These results indicate that the pretreatment of Mn-doped Fe2O4 nanoparticles loaded on activated carbon can optimize the removal of Phenol from aqueous solution.

Quantitative structure–property relationship (QSPR) models establish relationships between different types of structural information to their properties. In the present study the relationship between the molecular descriptors and quantum properties consist of the heat capacity (Cv/J mol-1K-1) entropy (S/J mol-1K-1) and thermal energy (Eth/kJ mol-1) of 100 alkenes is represented. Genetic algorithm (GA) and backward-multiple linear regressions (BW-MLR) were successfully developed to predict quantum properties of alkenes. Molecular descriptors were calculated with Dragon software and the genetic algorithm (GA) method was used to selected important molecular descriptors. The quantum properties were obtained from quantum-chemistry technique at the Hartree-Fock (HF) level using the ab initio 6-31G* basis sets. The predictive powers of the BW-MLR models were discussed by using leave-one-out (LOO) cross-validation and external test set. Results showed that the predictive ability of the models was satisfactory, and the 2D matrix-based descriptors, topological, edge adjacency and Connectivity indices could be used to predict the mentioned properties of 100 alkenes

The aims this work to investigate the effects of (n=1, 2, 3) H+ ions functionalizing on the surface of B12N12 nanocage to detect and adsorb 5-Flucytosine (5-FC) drug using density functional theory at the WB97XD/6-31G(d, p) level of theory using Gaussian 09 software. The calculated results indicate that the adsorption of 5-FC drug on the surface of pristine and nH+ functionalized B12N12 nanocage is exothermic, and adsorption process in the presence of nH+ functionalized is more favorable than the pristine model. The thermodynamic results demonstrate that the adsorption of 5-FC on the surface of nH+ functionalized B12N12 nanocage in both the gaseous phase and in the presence of water or ethanol is spontaneous. The gap energy value of nH+ functionalized of B12N12 nanocage is more than the original value and so the conductivity of the system is lower than the pristine model. The AIM and RDG results confirm that the interaction between 5-FC with B12N12 is noncovalent type. The nonlinear optical (NLO) results show that the polarizability (α) and hyperpolarizability (β) of all adsorption models is in range (202.30 to 214.34 a.u.) and (42.18 to 603.98 a.u.) respectively, the NLO and TD-DFT results demonstrate that the optical properties of nanocage in the presence of 5-FC drug and nH+ functionalized change significantly. These results can be useful for making carrier, delivery, and detection of drugs in the biological system.

Precipitation method was applied to synthesize pure and PbS (1−x) Mn (x = 0%, 5%, 10% and 15%) nanoparticles. There have been reports on the usefulness of Mn-doped PbS (PbS:Mn) nanoparticles in removal Benzyl Paraben (BP) dye from aqueous solutions. The distinctive features of this novel material were identified using different techniques like BET, XRD, SEM and FT-IR. The optimal conditions for the (BP) dye removal were found to be 2, 15 min, 100 mg/L, and 0.1 g for pH, contact time and adsorbent dosage, respectively. Regarding the Kinetic models both pseudo-first-order and pseudo-second-order diffusion models of (BP) dye revealed that the kinetic of adsorption process followed second-order equation model. After using various Isotherm models to fit the experimental equilibrium data with, the adequacy and applicability of Langmuir model has been proven. Adsorption mechanism for these adsorbents was considered to be physical which was confirmed by the E (kJ mol-1) obtained from Dubinin–Radushkevich isotherm for pure PbS, PbS/Mn-5%, PbS/Mn-10% and PbS/Mn-15% were roughly -710.0, -780.0, -830.0 and -920.0 (kJmol-1) respectively. The thermodynamic parameters including enthalpy, entropy and Gibbs energy were calculated for the adsorption of these (BP) dye using Mn-doped PbS nanoparticles suitable, spontaneous and exothermic. The maximum adsorption capacity of the (BP) dye for pure PbS, PbS/Mn-5%, PbS/Mn-10% and PbS/Mn-15% were roughly 80.0, 105.0, 131.0 and 145.0 mg/g, respectively. The findings revealed the appropriateness of Mn-doped PbS (PbS:Mn) nanoparticles as an adsorbent for (BP) dye deletion from aqueous solutions.

Flotation is a main technique for extraction of elements from ores with suitable grades, which is based on separating valuable particles from unwanted particles. Apatite with the formula of P2O5 can be extracted by flotation method. There are some gangue components in apatite. Hematite is one of the most important gunge minerals in phosphate ore. Fatty acids are the traditional collectors for apatite flotation but they have a poor selectivity against phosphate minerals. So, auxiliary reagents are needed. In this work, we formulated two collector packages with the same fatty acids and Nonylphenol ethoxylated (NPE) as anionic and nonionic surfactants but different in auxiliary reagents, and made a comparison between them in apatite flotation. Auxiliary reagents are polyethylene oxide (PEO) and paraffin. The results indicated that selectivity due to utilize PEO is better but for recovery, using paraffin is suitable. PEO can improve selectivity of the collector but paraffin can increase the collecting ability.