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Zirconium dioxide nanomaterials doped with samarium were produced through a bio-template method, utilizing citric acid as a fuel. Various advanced methods, for instance, XRD, TEM, EDX, PL, XPS, and UV–Vis spectrophotometry, were employed to characterize the compositions. XRD analysis confirmed that all peaks corresponded to the tetragonal phase of ZrO₂, with no presence of impurities from other phases. The elemental composition was analyzed using EDX, verifying the presence of Zr, Sm, and O. The energy gap widening concerning the pure ZrO₂ may be the well-known Moss–Burstein shift. This shift was linked to an increase in the bandgap (from 5.25eV to 5.54eV) with increasing concentrations of Sm. This observation was made during the analysis of the photocatalysis of pure ZrO₂ and various concentrations of Sm-doped ZrO₂ for Methylene Blue. The augmentation of Sm doping resulted in an improvement in the efficiency of removing Methylene Blue, increasing the removal rate from 35% to 80%.

The study of haemin-catalysed oxidation reactions was extended to substituted aromatic rings. Both electron-donating and electron-withdrawing substituents on aromatic rings act as para- and meta-directing agents in the presence of tetrakis(2,6-dichlorophenyl)porphyrin iron(III) chloride as catalyst and m-chloroperbenzoic acid as oxidant. A new kinetic method for measuring relative rates of epoxidation of alkenes and related compounds has been developed; while steric hindrance results in decreasing the rate of hydroxylation, electron-rich and electron-withdrawing substituents were found to increase the rate of hydroxylation. A linear relationship between the logarithm of the relative rate of hydroxylation and σ Hammet is obtained, although electron-donating and electron-withdrawing substituents fit separate lines. Addition of pyridine to haemin was shown to increase the yield of epoxidation but decrease the yield of aromatic hydroxylation.

In this paper we have tried to develop a semi-empirical formula for estimation of starting time of reactions during mechanical alloying process according to self-propagating high temperature synthesis (SHS) mechanism. For this purpose, three SHS systems containing Ti–C, Mo–Si and Si–C were selected and their behaviors were observed. Aforementioned systems were milled in a planetary ball mill equipped with temperature sensor detector of cups. Samplings were done at different times of discontinuously milling. To change mills' energy, stainless steel and tungsten carbide balls were used. In order to detect the phases and characterizations of milled powder, XRD instrument was utilized. Results showed that all productions were synthesized after sudden increase in temperature. Maximum measured temperature and critical time had up and downtrends for production of TiC, MoSi₂ and SiC, respectively. Crystalline size of milled powder had nano-meter scale. By using experimental data along with theoretical equations, a semi-empirical formula between critical time for transformation of raw materials to productions, type of milled system and ball mill parameter can be presented with high accuracy. According to calculated formula, critical time was related to ball mill energy and Gibbs free energy of milled system with direct and inverse proportionality, respectively.

We investigate higher order entropies for compressible fluid models and related a priori estimates. Higher order entropies are kinetic entropy estimators suggested by Enskog expansion of Boltzmann entropy. These quantities are quadratic in the density ρ, velocity v, and temperature T renormalized derivatives. We investigate governing equations of higher order entropy correctors and related differential inequalities in the natural situation where the volume viscosity, the shear viscosity, and the thermal conductivity depend on temperature, essentially in the form T^ϰ, as given by the kinetic theory of gases. Entropic inequalities are established when ‖log ρ‖_BMO, , ‖log T‖_BMO, ‖h∂_x ρ/ρ ‖_L^∞, , ‖ h∂_xT/T‖_L^∞, and are small enough, where is a weight associated with the dependence of the local mean free path on density and temperature. As an example of application, we investigate global existence of solutions when the initial values log(ρ₀/ρ_∞), , and log(T₀/T_∞) are small enough in appropriate spaces.

Many physiological and anatomical changes occurring during the pregnancy period have been widely documented and reported in the literature. This study involved the participation of pregnant subjects, divided into their respective trimester periods, with post-partum normal subjects. Kinetics analyses were performed on each subject using the Peak Motus 2000 system, and comparison between the pregnant subjects in different trimester, and also the post-partum normal subjects, were conducted. The step width generally increases as the subject is progressing through her pregnancy periods. From the average, the step width increases from 0.168 m in the first trimester to 0.350 m in the third trimester, which is an increase of nearly 50%. It can be generally appreciated that the step width increases as the pregnancy period progresses. It shows that these increases may be attributed to the increase of the body weight of the subject as she gains more weight towards the end of her pregnancy.

The present study investigated the adequacy of the interaction between the center of mass (COM) and the center of pressure (COP) for maintaining dynamic stability during Tai Chi Chuan (TCC) Push Hands movements in a fixed stance. The COM of the whole body and COP were calculated. Four TCC experts, with 10.3 ± 1.7 years' experience in the Push Hands technique, and 4 TCC beginners, with 2.5 ± 1.3 years' Push Hands experience, were recruited. An Expert Vision Eagle motion analysis system collected kinematic data and 4 Kistler force plates collected the ground reaction force data. The expert group of TCC practitioners showed a significantly more vertical (P = 0.001) direction in the neutralizing circle, and significantly larger values for anterior–posterior (A–P) (P = 0.006) and vertical (P = 0.0004) displacement in the enticing circle, than the beginner group. Compared with the beginner group, the expert group demonstrated significantly greater velocity A–P (P = 0.001) and vertical (P = 0.001) COM displacements in the enticing circle. A significant extent main effect (P = 0.0028) was observed for the COP_A–P excursion between the expert and beginner groups during Push Hands movements. The greater A–P force generated by both groups during the initiation of the Push Hands cycle probably reflects the more rapid and forward-oriented nature of this movement. The TCC beginners might have difficulties with movement transfers because of disruptions in the temporal sequencing of the forces. Overall, results indicated that the initial experience-related differences in COM transfers are reflected in the Push Hands movement cycle.

The goal of this study was to investigate the differences in ground reaction force during a Tai Chi Chuan (TCC) pushing movement between those with and without TCC experience through a detailed 3D dynamic analysis of the lower extremities. Seven TCC practitioners who had practiced the TCC push-hands movement for 6.0 ± 4.8 years and eight males without any TCC experience were recruited in this study. An eight-camera Expert Vision Eagle motion analysis system and two Kistler force plates were used to collect kinematic data (100 Hz) and the ground reaction force (1000 Hz). About 34 retro-reflective markers were placed on anatomical significant locations that determine embedded axes for segments. Results showed that the angular motions of the knee joint were different between the two groups, both in pattern and magnitude. Compared with the TCC group, the non-TCC group had significantly smaller peak abduction angles at the ankle joint (p < 0.05). The magnitude of the vertical force of the TCC group was greater, whereas the medial and posterior shear forces were smaller. The significant difference in vertical force (p < 0.05) and fraction opponent force of vertical force were found significantly different (p < 0.05) between the two groups. The patterns of the anteroposterior component of the ground reaction force during pushing were different, but those for the other two components were similar. Different lower-limb kinematics and kinetics were found between those with and those without TCC experience during TCC pushing movement and it was also found that the TCC practitioners could generate more effective force transfer than the group with no prior TCC experience. It was further concluded that vertical force plays an important role in a pushing movement, and posterior force exerted from the opponent was absorbed and transformed into anterior force to help the TCC practitioners remain stable.

Background: Although there are a few studies on kinetic and kinematic parameters of scoliotic subjects, it is still controversial whether gait performance of scoliotic subjects differs from that of normal subjects or not. Moreover, there is lack of information regarding joint contact force of scoliotic on convex and concave sides. Therefore, this study examined these issues.

Method: Two groups of children (healthy and children with scoliosis, each group consisting of 5 subjects) participated in this study. The force applied on leg and motions of body parts were evaluated using a Kistler force plate and motion analysis system, respectively. Joint contact forces, muscles length were evaluated in both groups and on both sides (in scoliotic subjects) with OpenSim software. The difference in the parameters between healthy children and scoliotic subjects, and also concave and convex sides, was determined using the independent $t$ test. $P$ value was set at $\le 0.05$.

Results: The results of this study showed that there was no difference between the forces applied on the leg, range of motions of the joints (hip, knee, ankle, pelvic and trunk), muscles length and joint contact force, neither between normal and children with scoliosis, nor between concave and convex sides $(p>0.05)$.

Conclusion: The findings revealed that scoliosis deformity with curve less than $40^{\circ }$ does not have any significant effect on joint contact force, kinetic and kinematic parameters.

Wastewater discharge from textile industries contribute much to water pollution and threaten the aqua ecosystem balance. Synthesis of agriculture waste based adsorbent is a smart move toward overcoming the critical environmental issues as well as a good waste management process implied. This research work describes the adsorption of methylene blue dye from aqueous solution on nickel oxide attached magnetic biochar derived from mangosteen peel. A series of characterization methods was employed such as FTIR, FESEM analysis and BET surface area analyzer to understand the adsorbent behavior produced at a heating temperature of 800${}^{\circ }$C for 20min duration. The adsorbate pH value was varied to investigate the adsorption kinetic trend and the isotherm models were developed by determining the equilibrium adsorption capacity at varied adsorbate initial concentration. Equilibrium adsorption isotherm models were measured for single component system and the calculated data were analyzed by using Langmuir, Freundlich, Tempkin and Dubinin–Radushkevich isotherm equations. The Langmuir, Freundlich and Tempkin isotherm model exhibit a promising R²-correlation value of more than 0.95 for all three isotherm models. The Langmuir isotherm model reflectsan equilibrium adsorption capacity of 22.883mg$\cdot$g${}^{-1}$.

Due to its mechanical properties and ease of use, vinyl ester resin is enjoying increasing consideration. This resin normally is produced by reaction between epoxy resin and unsaturated carboxylic acid. In the present study, bis-phenol A based epoxy resin and methacrylic acid was used to produce vinyl ester resin. The reaction was conducted under both stoichiometric and non-stoichiometric conditions in the presence of triphenylphosphine as catalyst. The stoichiometric and non-stoichiometric experiments were conducted at 95, 100, 105 and 110°C and at 90 and 95°C respectively. The first order rate equation and mechanism based rate equation were examined. Parameters are evaluated by least square method. A comparison of mechanism based rate equation and experimental data show an excellent agreement. Finally, Arrhenius equation and activation energy were presented.

The selective oxidation of sulfides with hydrogen peroxide to give sulfoxides was carried out in aqueous solution by water-soluble manganese porphyrin as mimics of cytochrome P450-like catalyst. Different factors that influencing the selective oxidation of sulfides, for example, catalyst, amount of catalyst, solvent and reaction temperature were investigated. MnTE4PyP (meso-tetrakis(N-ethylpyridinium-4-yl) manganese porphyrin) was efficient and selective catalyst for oxidation of various sulfides. The reaction showed first-order dependence in both [sulfide] and [H₂O₂], and a fractional order respect to catalyst. Oxygen atom transfer mechanism involves high-valence intermediate was proposed, which was supported by kinetic orders and spectrophotometric evidences.

MIL-101(Cr)/AC was synthesized by in situ incorporation of activated carbon powder via hydrothermal method. The water stability, n-hexane adsorption and regeneration of the MIL-101(Cr)/AC were experimentally measured. The results showed that the MIL-101(Cr)/AC exhibited the larger surface area (3319.3m²/g) than that of MIL-101(Cr) and AC, respectively. The addition of activated carbon was beneficial to improve the yield of MIL-101(Cr)/AC. The pore structure parameter and XRD of the MIL-101(Cr)/AC changed little after in water for 24h. Furthermore, the adsorption capacity of MIL-101(Cr)/AC for n-hexane was 786mg/g, which increased to 23.0% and 27.7% compared with MIL-101(Cr) and AC, respectively. Kinetic fitting of data indicated that the pseudo-first order model can more accurately describe the adsorption process of n-hexane on MIL-101(Cr)/AC and the intraparticle diffusion was not the sole rate-controlling step. Besides, the regeneration efficiency of MIL-101(Cr)/AC was over 92% after 10 consecutive n-hexane adsorption/desorption cycles.

Si₃N₄–SiC composites were fabricated by spark plasma sintering at 1700${}^{\circ }$C for 480 S with MgSiN₂ and Y₂O₃ as additives. The morphology and phase characterization of the composites were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The values of $n$ parameter indicate that the grain boundary reaction is the rate controller at 1500${}^{\circ }$C and diffusion becomes the controlling step at 1550${}^{\circ }$C. The nanohardness and Young’s modulus attained the maximum value of 18.5 and 316GPa, respectively.

The adsorption behavior of acetic acid on zeolite 13X was studied at 25°C, 35°C and 45°C in a batch experiment. Experimental data were applied to pseudo-first-order and pseudo-second-order adsorption kinetic models, and tested against Langmuir and Freundlich isotherms. Thermodynamic parameters (ΔG, ΔH and ΔS) of adsorption were also calculated. The data fit the pseudo-second-order kinetic model and Freundlich isotherm well. The calculated values of ΔG, ΔH and ΔS indicate that the adsorption is spontaneous and endothermic; it causes an increased extent of randomness at the solid-solution interface.