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Nanocomposites produced with samarium(III) molybdate/N, P co-doped reduced graphene oxide (Sm2MoO6/NPRGO) combination may be very useful in the field of supercapacitors due to the active interaction between these two components. In this study, we used the sonochemical method, which is quite simple and cheap, to produce Sm2MoO6/NPRGO nanocomposite, which draws attention with its high-quality electrochemical performance. Surface and structural properties of Sm2MoO6 nanoparticles, NPRGO and Sm2MoO6/NPRGO nanocomposite structures were studied by X-ray photoemission spectroscopy (XPS), nitrogen adsorption/desorption studies, scanning electron microscopy, and X-ray diffraction analysis. The symmetric supercapacitive performance of the Sm2MoO6/NPRGO electrode exhibits a specific capacitance of 689 F g−1 (at 2 mV s−1) and could maintain 99.9% capacity after 4000 charge–discharge cycles. Additionally, the symmetric supercapacitors based on nanocomposite electrode demonstrate a high energy density (23.2 W h kg−1 at 250 W kg−1), outstanding power density (8000 W kg−1 at 14.4 W h kg−1). Generally, this nanocomposite was synthesized for the first time and its supercapacitive properties were investigated. The nanocomposite electrode exhibited good supercapacitor response, remarkable rate performance and excellent cycling stability in both 0.5 M Na2SO4 electrolyte.

Here, cerium (IV) molybdate nanoparticles (CeMo2O8) are anchored on the surface of an N, P co-doped reduced graphene oxide nanocomposite by a stepwise sonochemical approach and further investigated as an electrode for supercapacitors. The cerium (IV) molybdate/N, P co-doped reduced graphene oxide symmetric electrode exhibits an outstanding specific capacitance of 638 F g−1 at 2 mV s−1. The prominent electrochemical capacitive properties of nanocomposite electrode are attributed to the merits of high electrically conductive N, P co-doped reduced graphene oxide and short ion transport channels provided by CeMo2O8 nanoparticles together with the synergistic effect between the two combinations. Furthermore, the symmetric supercapacitor based on CeMo2O8/N, P co-doped reduced graphene oxide electrodes demonstrates a high energy density (29.7 W h kg−1 at 500 W kg−1), good power density (16,000 W kg−1 at 14.3 W h kg−1), and remarkable cycling stability (102.9% capacitance retention after 4000 cycles at 100 mV s−1). The results clearly show that co-doping small amounts of N and P onto the reduced graphene oxide, through a simple impregnating method, significantly improves the supercapacitive performance of the nanocomposite electrode.

Acquiring knowledge on the complex behaviors of bridges in an earthquake is of utmost importance for designing safe transportation systems. Earthquakes like Northridge 1994 showed that skewed angle in the bridge could lead to the failure of abutment and column because of the intensified demand for deck rotation around the vertical axis, especially in the near-fault zone. The present study attempted to examine how the skewed angle change affects the seismic response of curved and skewed bridges. To this end, a software model of two curved and skewed bridges verified through a field test was obtained. The results showed that the skewed angle change in far-fault zones has no significant effect on the seismic responses of these bridges, while in near-fault zones its effect is remarkable. In ramp bridges, the torsional force increases in the columns next to the abutment.

In this research, a new android app for smartphones for estimating some water quality parameters in carp fish ponds such as pH, electrical conductivity (EC), total dissolved solids (TDS), and turbidity is presented. Contact imaging was used to acquire images from the samples. To estimate pH, EC, TDS, and turbidity values, 12 features were extracted from each image. Features were used as input to the artificial neural network models. The performance of the models was evaluated by the R2 and RMSE parameters. Based on the results, the network with a structure of 12-15-4 was selected as the best model. The values of R2 for estimating pH, TDS, EC, and turbidity were 0.913, 0.993, 0.994, and 0.958, respectively, while the corresponding values for the RMSE were 0.054, 1.835, 3.766, and 0.262, respectively. Finally, this model was successfully implemented on an app named WaterApp on the android smartphone. For testing the app on the smartphone, the performance of the model was evaluated again using new images. According to the results, the R2 values for validation data by the developed WaterApp for pH, EC, TDS, and turbidity were 0.88, 0.913, 0.884, and 0.944, respectively.

French tarragon (Artemisia dracunculus L.) is a perennial herb in the family Asteraceae that is widely cultivated throughout the word. In order to study the effect of foliar application of Ca(NO3)2 and KNO3 on vegetative traits, essential oil yield, content and composition, a field experiment was conducted. Treatments including four levels of Ca(NO3)2 and KNO3 fertilizers (0, 1.5, 3, and 6 g/l) were set up in a factorial experiment based on Randomized Completely Block Design with three replications. The results showed that Ca(NO3)2 application significantly affected all tarragon vegetative traits, but had no significant effect on essential oil content. Furthermore, essential oil yield increased with Ca(NO3)2 treatments by an average of 64.4% compared to the control. Ca(NO3)2 fertilization increased leaf K and Ca contents. The gradual increase of Ca(NO3)2 rates decreased estragole by 18.6%. On the other hand, KNO3 fertilization significantly increased all of plant growth characters, leaf K and Ca contents. Foliar KNO3 application significantly increased essential oil content and the yield by an average of 42.5% and 119.6%, respectively. The lowest content percentage of estragole (76.83%) is obtained from 1.5 g/l KNO3 decreased by 0.6% an average when compared to the control. The interactive application of Ca(NO3)2 and KNO3 significantly affected the number of branch/plant, leaf K content and all of the essential oil constituents. Interactive treatment of Ca(NO3)2 and KNO3 decreased estragole content by an average of 12.9%. In general, it can be concluded that foliar application of Ca(NO3)2 and KNO3 can considerably improve the productivity traits, essential oil content, yield and composition of tarragon plant.

Artemisia dracunculus L. (tarragon), known as “tarkhun” in Iran, is a perennial herb in the Asteraceae family, which has a long history of use in culinary traditions. A factorial experiment based on the Randomized Completely Block Design with three replications was used. The treatments were performed at four level of foliar applications of Ca(NO3)2 and KNO3 fertilizers (including control (sprayed with water), 1.5, 3 and 6 gl -1 ). This experiment was conducted at field conditions in a farm in “Ray” in 2010. The results showed that Ca(NO3)2 application significantly increased plant height, fresh and dry matter yield by an average of 10.1, 35.8 and 33.5%, respectively. Essential oil content was not significantly affected with Ca(NO3)2 fertilization. Nevertheless, Ca(NO3)2 application increased essential oil content by an average of 64.4% compared with the control. Ca (NO3)2 foliar application increased N and Ca content of leaf tissues. The concentrations of P, K, Mg, Fe, Mn, Zn and Cu significantly affected by Ca(NO3)2 levels. Plant height, fresh and dry matter yield, essential oil content and yield significantly increased with KNO3 foliar application by an average of 4.4, 60.5, 50.4, 42.5 and 119.6%, respectively compared with the control. The KNO3 application significantly increased N, K, Fe, Mn and Zn concentrations compared with the control. Also, leaf P, Ca, Mg and Cu contents were influenced by KNO3 fertilization. The interaction between Ca(NO3)2 and KNO3 treatments was significant in leaf N, K, Mg, Fe, Mn, Zn and Cu contents.