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This article deals with an experimental investigation of thermal performance of mechanical draft wet cooling towers by changing various parameters such as hot water temperature, water flow rate, air mass flow rate and stage numbers of packing. In fact, this research attempts to focus on packing density influences with an emphasis on the role of stage numbers of packing. The results imply that coefficient of efficiency is in direct relation with air mass flow rate, hot water temperature and stage numbers of packing, while it diminishes by increasing the water flow rate. On the other hand, thermal images are provided for visualizing temperature distribution within the studied cooling tower. Afterward, these images are utilized so as to obtain pertinent temperature histograms and also temperature distribution along the vertical and horizontal directions for three packings. Finally, regression analysis is employed in order to derive design equations from the measured data. [ABSTRACT FROM AUTHOR]

One of the most fundamental properties of nanofluids is their viscosity. To determine the viscosity of these fluids, many models based on experimental or theoretical studies have been developed. However, the bulk of these models either offer outcomes that are inaccurate or are restricted to a certain operating condition. As a result, determining the viscosity of nanofluids is a difficult undertaking. In this work, a novel model based on Least Squares Support Vector Machines (LSSVM) was provided to predict the viscosity of hybrid nano-lubricants of MWCNT-metal oxide nanoparticles/engine oil. Metal oxide nanoparticles including Al 2 O 3 , ZnO, SiO 2 , TiO 2 , CuO, and MgO, and engine oils including 5W50, 10W40, 20W50, SAE40, and SAE50 were considered in the studied hybrid nano-lubricants. The reliability of the proposed model was determined by comparing its outputs to experimental data obtained at various temperatures, nanoparticles' concentrations, shear rates, and solid volume fractions. Additionally, the LSSVM model's coefficient of determination for all data was found to be 0.99649, demonstrating its high accuracy. Moreover, using the Monte-Carlo technique, the sensitivity analysis of the input variables on the output was computed which showed that the most sensitive variables for this model are shear rate, lubricant density, and nanoparticles volume fraction. This work highlights the requirement for a trustworthy approach to determine the viscosity of hybrid nano-lubricants and suggests one. [ABSTRACT FROM AUTHOR]

Wet cooling towers play a prominent role in the transfer of waste heat from industrial thermodynamic cycles. However it is a complicated task to dictate and optimize their operational conditions on account of different mass and heat transfer mechanisms between water and air flows. In this research, air mass flow rate, hot water temperature, water flow rate and stage numbers of packing are changed experimentally in order to investigate their influences on the cooling tower performance. As a matter of fact, this research attempts to focus on packing density effects with an emphasis on the role of stage numbers of packing. Consequently, the obtained results indicate that coefficient of efficiency is in direct relation with the hot water temperature, stage numbers of packing and air mass flow rate, while it diminishes by increasing the water flow rate. On the other hand, the captured thermal images and pertinent temperature histograms are investigated so as to visualize and calculate the temperature distribution within the studied cooling tower. Eventually, mathematical equations are derived from regression analysis of the measured data to recommend some practical procedures for the sake of reaching optimum operating conditions of forced draft wet cooling towers. [ABSTRACT FROM AUTHOR]

Natural draft wet cooling towers are one of the most widely-used types of wet cooling towers in the large-scale power plants. In the present research, the heat transfer performance of natural draft counter-flow wet cooling towers is investigated under cross-wind and windless conditions by virtue of an innovative wind-creator setup provided so as to implement intrinsic features of the natural wind speed profile precisely. As a matter of fact, this investigation will focus on the influences of cross-wind velocity, inlet water temperature and water flow rate on the water temperature difference and cooling efficiency of the studied cooling tower, with an emphasis on the role of wind speed features. Interestingly, a twofold trend is exhibited by the water temperature difference and cooling efficiency with respect to variation of the cross-wind velocity. Furthermore, to have a more applicable study, regression analysis of the experimental results is utilized for the sake of developing general mathematical equations and thus facilitating further analyses. Finally, these mathematical equations are employed in order to recommend a guideline for the purpose of reaching optimum operating conditions of natural draft wet cooling towers. [ABSTRACT FROM AUTHOR]

There are different mass and heat transfer mechanisms between water and air flows inside wet cooling towers (WCTs) so that it is a very difficult task to manage or optimize their operations. In this experimental work, the WCT performance is parametrically investigated in order to understand effects of water flow rate, inlet water temperature, type and arrangement of packing, and mass flow rate of air. Three different types of PVC packings (7, 9 and 18 ribs) are studied in this article separately to investigate influences of rib numbers. Furthermore, operation of the WCT is investigated by changing the inlet water temperature, rib numbers of packing, and flow rate of air and water. Ultimately, a guideline is proposed to reach optimum operating conditions of WCTs by virtue of mathematical equations derived from regression analysis of the measured data. [ABSTRACT FROM AUTHOR]

• Study addresses adoption of conservation agricultural initiatives (CAIs). • Compatibility and observability affect adoption. • Farm revenue affects CAIs adoption. • Electrical conductivity and organic carbon content are significantly different between the two groups of farms. • Topographical information indicates that CAIs farms are with a gradient of less than 5%. Over the past decades, agro-ecological measures, such as conservation agricultural initiatives (CAIs) have been widely implemented in developing countries, in like manner with Tabriz city as would be a leading case situated in northwest Iran. In light of linear discriminant analysis (LDA), this cross-sectional research calls on a knowledge gap respecting the differentiation of farmers who become involved in CAIs (adopters) from those not involved (non-adopters), as three data modules, including attitudinal, soil testing, and topographical data, were used. The study takes advantage of a sample of 382 respondents, stratified as regards the geographical location of their farms. Using theory-triangulation, the theoretical foundation enfolds demographic theory, the theory of planned behavior, innovation diffusion model, and resource-based model. The results of hierarchical LDA provide evidence that the hypothesized model is entitled to be fitted with data and accordingly three variables including (1) observability, (2) farm revenue, and (3) compatibility ascertain adopter farmers from non-adopter ones. Furthermore, it was revealed that the soil dynamic quality features, such as electrical conductivity, EC, (dS m−1) (Mann-Whitney U = 353, P < 0.05) and organic carbon content, OC (%), (Mann-Whitney U = 935.5, P < 0.05) were significantly different between the two groups of farms, while carbonate calcium equivalent, CCE (%) (Mann-Whitney U = 935.5, P > 0.05) showed no significant differences. Likewise, the topographical data analyzed in ArcGIS software make manifest that CAIs farms have more steady topographic features rather non-CAI farms and are also situated in the regions with a gradient of less than 5%. In conclusion, the paper delivers management implications for the agricultural extension and authorities of the agricultural research centers who tend to promote CAIs in on-site and off-site farmlands. [ABSTRACT FROM AUTHOR]

Kisspeptin is a multifunctional neurohormone, primarily involved in the regulation of reproduction. We tested whether peripheral administration of kisspeptin10 (KP-10) via intraperitoneal injection or slow release affects reproductive hormones and metabolites in Sterlet sturgeon (Acipenser ruthenus). Plasma and mucus 17β-estradiol (E 2), and testosterone (T), plasma and follicular vitellogenin (VTG) and calcium (Ca) as well as glucose and lipids were determined. Mature Sterlet sturgeon were grouped into six groups: saline i.p injection (control), human kisspeptin (hKP-10) i.p injection; acipenser kisspeptin (aKP-10) i.p injection; hKP-10 (slow release); aKP-10 (slow-release) and no treatment control. No effect for KP-10 on sturgeon body weight was found after 4 weeks of treatment. Multivariate analysis revealed a significant disparity in plasma E 2 levels. It was significantly different between groups (time, P = 0.0022). E 2 in epithelia mucosa showed significant difference between and within groups in the acute group (time, P = 0.0252; treatment, P = 0.0423; time × treatment, P = 0.0429). T levels were unaffected by treatments (P > 0.05). The presence of synthetic aKP-10 led to an elevation in oocyte and plasma VTG levels (P < 0.05). Prolonged exposure to this peptide resulted in an increase in plasma calcium levels. Simultaneously, there was an augmentation in the number of mature follicles. Regardless of the duration of exposure, aKP-10 significantly elevated plasma glucose levels in Sterlet (P < 0.0). Additionally, KP-10 led to an increase in plasma lipids and cholesterol in Sterlet. Overall, our data support an involvement for KP-10 in the regulation of gonadal steroid hormones, oocyte maturation and metabolite levels in sturgeon, suggesting a positive role for this peptide in the reproductive physiology of this species. [Display omitted] • KP-10 administration increased plasma 17β-estradiol levels in Sterlet sturgeon. • Surface epithelial mucosa served as an immediate hormonal indicator post aKP-10 administration. • Peripheral KP-10 modulated vitellogenic development and calcium levels in Sterlet sturgeon. • Metabolite factors such as glucose and lipids were increased by KP-10 in Sterlet sturgeon. [ABSTRACT FROM AUTHOR]

• Several playa surfaces have developed on geomorphic surfaces of Urmia Playa Lake. • Erodible fraction varied between 40% and 90% among playa surfaces. • Playa surface type was a determining factor in its resilience to wind erosion. • Abandoned agricultural lands had the highest erodible fraction. • Salt crusts and clay flats were more resilience against wind erosion. Despite the great extent of Urmia Playa Lake (UPL), researchers have rarely ever studied the development of playa surfaces and their vulnerability to dust emission. Therefore, we aimed the current research to study the formation of UPL surfaces and how their physicochemical, mineralogical and geomorphological characteristics affect their susceptibility to wind erosion. An area of 41 km2 was chosen including lands from UPL and adjacent Agricultural Lands (AL). Different playa surfaces were identified on different geomorphic surfaces and mapped using Landsat images. Later, 75 soil samples from depth of 0–5 cm of different map units were collected and subjected to physicochemical analysis. Soil Erodible Fraction (EF) was also measured as an index for the wind erodibility of the examined soil surfaces. X-Ray Diffraction (XRD) and X-Ray Fluorescence (XRF) analysis of soil samples from three playa surfaces with significantly different EF values were also conducted. Major reasons for the development of different playa surfaces were found to be basically related to geomorphic surfaces on which they have developed, size and mineralogical composition of the sediments as well as the landscape position and depth to the groundwater. Statistical analysis of EF of different playa surfaces and AL showed that Salt Crusts (SC) had the lowest mean EF value due to the formation of a thin layer of salt on its surface as it has developed on low stand geomorphic surface being fine-textured by nature and rich in Na, Mg and Cl ions. Abandoned Agricultural lands (AA) and AL had the highest mean EF values. High sand content of soils with anthropogenic origin along with conventional tillage practices resulting in soil organic matter loss and over grazing were the major reasons of their high EF. Therefore, these surfaces need to be monitored carefully and to be of high priority of conservation and dust control programs in the region. [ABSTRACT FROM AUTHOR]

Under the fifth strategic development plan of Iran, the government is necessitated to trigger the agro-ecological initiatives like conservation agriculture (CA) by stimulating farmers to become involved in the schemes as efficiently as possible, along the lines of global policies to enhance environmentally-friendly development. This study, as being the case, calls for the knowledge gap of motivation-intention-behavior, investigating the association of diverse motivations of 382 farmers in Tabriz, East Azerbaijan, with the soil conservation behavior (SCB), also inclusive of the contribution of CA features, including relative advantage, compatibility, complexity, observability, and testability, as the farmers were stratified to low and high SCB. The theoretical framework consists of the theory of planned behavior (TPB) and motivational model (MM), the former is commonly used and the latter has the potential to be given much attention, conceptualized by well-being, identity, hedonistic, and idealistic concepts. The study provides evidence that 70.42% of farmers adhere to and carry out SCB at a low rate; whereas, 29.58% of the rest has a high adoption rate. The results also illustrate that attitude towards CA contributes to influencing SCB, as well as the significant and positive impact of PBC on behavioral intention and SCB. While well-being motivation has a negative impact on attitude towards CA, behavioral intention, and SCB, identity and hedonistic motivations have a significant and positive impact on attitude and SCB that are mediated by behavioral intention. The paper concludes that (1) the agricultural extension needs to change farmers' attitudes by making farmers aware of the relative advantage, compatibility, and testability of CA, (2) farmers should receive technical, financial, and educational support to increase their volitional control on CA, (3) it is strongly suggested addressing the primary obstacles to SCB, which are facilitated by delivering the subsidized agricultural inputs (e.g., fertilizer, fuel, and livelihoods) to farmers with well-being motivations, (4) the agricultural extension is also recommended recognizing farmers with identity and hedonistic incentives, they are as a reference group and are imitated by non-adopter or slowly adopter farmers. • Study addresses the intake of conservation agriculture. • Attitude towards conservation agriculture affects soil conservation behavior. • Behavioral control affects behavioral intention and soil conservation behavior. • Well-being motivations affect attitude towards conservation agriculture negatively. • Identity and hedonistic motivations affect intention and soil conservation behavior. [ABSTRACT FROM AUTHOR]