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• DRFC solar-hydrogen: Off-grid irrigation for arid areas. • Cost-effective: 9% lower than diesel, COE $0.529, NPC $5365. • Zero emissions vs. diesel's 993 kg/year. • Steady fuel cell: Consistent hybrid power, resilient to seasonal shifts. • Global impact: Reclaim deserts, boost food security sustainably. This study focuses on the challenges of desertification and non-arable lands in off-grid remote areas with hot and arid climates. Despite the availability of groundwater, these areas require access to electricity at night to operate the water pumps to spray the crops due to high evaporation rates during the daylight. The absence of grid electricity necessitates the utilize of diesel generators to power irrigation systems, representing a significant contributor to climate change and the depletion of fossil fuel reserves. Addressing nocturnal electrification using sustainable solutions is crucial for reclaiming such areas and eliminating the environmental impacts of diesel generators. The study introduces a novel closed-loop Discrete Regenerative Fuel Cell (DRFC) solar-hydrogen storage irrigation system designed explicitly for nocturnal utilization in water-scarce regions to rectify this concern. The study then assesses its performance compared to a conventional diesel generator system when supplying a one kW water pump for a sample land area of 10 dunams. Using the HOMER Pro simulation tool, the simulation results strongly support the assertion that the PV-hydrogen irrigation system intended in this study exhibits superior techno-economic performance compared to the conventional diesel-irrigation system. A comprehensive analysis of the net present cost (NPC) and cost of energy (COE) between the two systems reveals that the proposed system achieves values of $0.529 and $5365, respectively. In contrast, the diesel system records values of $0.572 and $5796, respectively. These findings indicate a notable 9 % reduction in overall costs associated with implementing the proposed system. Additionally, the fuel cell showed stable performance across varying months which implies a consistent and reliable contribution to the overall electrical power generation within the hybrid system, regardless of seasonal fluctuations in solar power and temperatures. Furthermore, in terms of environmental impact, our findings highlight a significant advantage of the proposed system over the diesel generator. Specifically, the proposed system produces zero carbon emissions, while emissions from the diesel generator were notably higher at 993 kg/year. It is essential to emphasize that the integration of fuel cells into the proposed system holds the potential to offer a clean source of drinking water for farmers and workers in the area. The implications of these findings can help the research community develop and facilitate the reclamation process of agricultural lands worldwide that face similar challenges to the study region. This could lead to subsequent global environmental and economic benefits, such as reducing the spread of desertification, enhancing productivity, improving food security, promoting environmental sustainability, and creating economic opportunities. [ABSTRACT FROM AUTHOR]

• A 2DOF fractional order control of a nonlinear and unstable system is investigated in this paper. • Analytical model based method is developed to design the parameters of the fractional order PD controller. • The fractional order controllers of the inner and outer loops are tuned to have a constant phase margin of the open-loop. • Based on experiment on a real ball and beam system, performance of the proposed controller is highlighted. Control engineers and researchers face challenges to design an efficient controller for Ball and beam system due to its nonlinear and unstable properties. This paper investigates two Degrees of Freedom fractional order control of the ball and beam system. It involves the model based method to design controllers' parameters for the corresponding linear model. The fractional order controllers are specially tuned to have a constant phase margin of the open-loop. This characteristic ensures the robustness of the controllers to the variations of system gain. This paper presents a proper evaluation and comparison between integer and fractional order controllers. Performance of each controller is evaluated in terms of set-point tracking, disturbance rejection, and robustness. The comparison between two controllers is validated through both simulation and experimental results. Strengths and weaknesses in the real-time control are also indicated. [ABSTRACT FROM AUTHOR]

Highly aligned titania (TiO 2 ) nanotube (NT) arrays have been grown on titanium sheet by using a self organized anodic oxidation method at different potentials (34–74 V) in a NH 4 F and ethylene glycol based electrolyte. Two sets of TiO 2 NT arrays have been fabricated with and without using cooling systems. Without cooling system, the solution temperature is increased from 25 °C (room temperature) to 63 °C with increase of anodization potential from 34 to 74 V. The temperature has been maintained to 25 °C by using water based cooling system. In both sets of samples, the pore diameter of TiO 2 NT arrays increases with increase of anodization potential. The maximum pore diameter has been (outer: 224 nm, inner: 172 nm) achieved with TiO 2 NT arrays (at 74 V) without using cooling system. The photocatalytic activity of the TiO 2 NT arrays is evaluated by the decomposition of methanol by the use of Fourier transform infrared spectrophotometer. The TiO 2 NT (at 44 V) sample has been fabricated without using cooling system, which shows the higher photocatalytic activity than the sample at other potentials. Using cooling system, the TiO 2 NT (at 54 V) sample shows the higher photo-decomposing property than the sample at other potentials. The TiO 2 NT (at 54 V) sample with cooling system shows the higher rate (photocatalytic activity) constant ( k = 0.0216) than the TiO 2 NT (at 44 V) sample without using cooling system ( k = 0.0186). The photocatalytic activity has been correlated with the nanostructural variation of TiO 2 NT arrays at different potentials without (self-grown solution temperature) and with water based cooling systems. [ABSTRACT FROM AUTHOR]

This work was carried out to investigate the comparative effects of phosphorus and boron doing in vapor–liquid–solid (VLS) growth. Doped Si microneedles were grown by VLS mechanism at the temperature of 700 °C or less using Au as the catalyst. VLS growth using in-situ doping with the mixed gas of Si 2 H 6 and PH 3 produced phosphorus doped n-Si microneedles at Au dot sites, whereas, the mixed gas of Si 2 H 6 and B 2 H 6 produced boron doped p-Si microneedles. The variation of growth rate, diameter, resistivity, impurity concentration and carrier (electron, hole) mobility of these n-Si and p-Si microneeedles were investigated and compared with the variation of dopant gas (PH 3 or B 2 H 6 ) flow, with a fixed flow of Si gas (Si 2 H 6 ). This comparative study shall be helpful while fabricating devices by growing n-Si and p-Si microneedles one above another by multistep (2-step or 3-step) VLS growth. [ABSTRACT FROM AUTHOR]

In this study, an attempt has been made for tailoring the surface features of an 18 vol% porosity containing Ti 23Nb alloy manufactured via powder metallurgy method. The aim was enhancing the wear resistance without sacrificing the mechanical properties. For this purpose, porous Ti 23Nb alloys having hardness of 280 HV 0.025 were subjected to thermal oxidation (TO) at 600 °C in air for two different holding times. TO duration of 6 h, which introduced a ~ 0.5 μm thick TiO 2 -rutile type exterior oxide layer (OL), provided surface hardness of 620 HV 0.025. Extension of TO duration to 60 h caused covering of the surfaces with a ~ 3.0 μm thick OL and increase of surface hardness to 980 HV 0.025. As the result of the increased surface hardness, TO'ed. alloys showed superior sliding wear resistance coupled with a reduction in friction coefficient (COF) against alumina ball in 1.5× simulated body fluid (SBF) when compared to the as-sintered state. Despite having the highest surface hardness, the alloy TO'ed. for 60 h exhibited slightly higher wear loss and COF than the alloy TO'ed. for 6 h. More important than this, the alloy TO'ed. for 60 h collapsed at a compressive stress well below the yield strength of the alloy TO'ed. for 6 h, which exhibited almost similar compressive stress-strain curve with that of the as-sintered alloy. From this perspective 6 h appeared as a promising TO duration for the examined porous alloy to be used in biomedical applications as it preserves the mechanical properties while providing remarkable enhancement in the wear resistance. [Display omitted] • Surface hardness of 18 vol% porosity containing Ti 23Nb increased upon TO • Wear resistance is remarkably increased after TO at 600 °C in air for 6 and 60 h • TO duration of 60 h dramatically reduced the compressive strength • TO of 6 h provided the lowest wear rate and COF without sacrificing strength [ABSTRACT FROM AUTHOR]

The measurement of impact force by use of a piezoelectric force transducer or similar device is complicated by: (i) the transducer is mechanically resonant, and the output signal is therefore not necessarily a direct measure of the input force, particularly if the contact time is near to the period of resonance; and (ii) the transducer’s mechanical characteristics, such as mass and stiffness, mean that the transducer itself affects the impact characteristics and force profile. This paper describes an attempt to measure impact force profiles without the use of a separate force transducer. However it has been found that the technique is not suitable due to poor repeatability. [ABSTRACT FROM AUTHOR]

Abstract: A new series of 1H- and 2H-pyrazole derivatives (35 final compounds) has been designed and synthesized in this study. A selected group (13 compounds) was then tested over a panel of 60 cancer cell lines at a single dose concentration of 10μM. At this concentration, six compounds have showed moderate to strong mean inhibitions, and were further tested at five-dose testing mode to determine their IC50 over the 60 cell lines. The IC50 values of the tested compounds indicated high potency (as for compound 10f) as well as high efficacy (as for compound 11e). Accordingly, compound 10f was then tested at a single dose concentration of 10μM over a panel of 54 kinases to determine its kinase inhibitory profile. The compound has showed good selectivity towards FLT3 kinase, associated with a moderate potency, with an IC50 value of 1.74μM. [Copyright &y& Elsevier]

Abstract: A new series of N-substituted-2-aminopyrimidines based on the ‘4-(pyridin-3-yl)pyrimidin-2-amine’ scaffold of Imatinib has been designed and synthesized. A selected group from the target compounds was tested over a panel of 60 cancer cell lines at a single dose concentration of 10μM, and the two most active compounds, 25b and 30, were further tested in a five-dose testing mode to determine their IC50 values over the 60 cell lines. Compound 30 has showed good potencies and high efficacies, and was accordingly tested at a single dose concentration of 10μM over a panel of 54 kinases. At this concentration, the compound has showed multiple inhibitions over a number of oncogenic kinases, including ABL1, AKT1, LCK, C-SRC, PIM1, FLT3, FYN, and KDR. A molecular modeling study was made by docking of the most active compound 30 and its inactive analog 29 into the kinase domain of ABL1 to investigate their possible binding interactions. [Copyright &y& Elsevier]

Abstract: The efficacy of the RapidChek Select, an alternative rapid method based on lateral flow technology, for the screening of Salmonella in meat and meat products, was compared with the current ISO reference culture-based method. Of the 265 routine samples examined, 61 were found to be positive for Salmonella by both methods. The percentage of agreement between the results of two methods was determined as 98%. All presumptive positive results obtained by the RapidCheck Select were confirmed to be positive by ISO method. For five samples ISO method gave positive result, while RapidChek Select gave negative result. The limit of detection (LOD50) of RapidChek Select and ISO methods for minced beef meat samples were 1.00cfu/25g and 0.63cfu/25g, respectively. For sausage samples, LOD50 of both methods were 2.00cfu/25g. As a result, the high agreement between two methods and the comparable detection limits of two methods showed that the RapidChek Select is an efficient alternative method for the screening of Salmonella in meat and meat products. [Copyright &y& Elsevier]

Estimation of drill cuttings particle sizes provides near real-time information that can be utilized in drilling operations. The analysis and interpretations of these rock samples is largely manual. Results are qualitative and can be inconsistent. We propose a practical automated method for estimating drill cuttings particle sizes using digital images. The proposed method is robust and combines several well-known and time-tested techniques like: K-means clustering, numerically stable ellipse fitting, and standard morphological operations. Images are first preprocessed and clustered based on color values. The resultant grain mask is enhanced using binary morphological operations. Measurements are then extracted from the mask based on the major and minor axis fitted to the particles. The developed method is tested on drill cuttings digital images from four wells with varying lithologies and particle sizes. Sensitivity analysis on imperfect images shows the robustness of the methodology. The automated results validated against manual measurements show a difference of less than ten percent. Performance of the algorithm is in the order of seconds, which allows for its use in near real-time applications. • A method for automated drill cuttings size estimation is developed. • The automated results validated against manual measurements show a difference of less than ten percent. • The proposed method runtime is in the order of seconds per image, allowing near real-time applications. [ABSTRACT FROM AUTHOR]

Extensive research on the effect of spark-plasma sintering and free forging on the microstructure, transformation temperature, and superelasticity of Ti-23 at% Nb shape-memory alloys (SMAs) was undertaken. Based on the obtained results, it was found that the specimen showed significant results after deformation than the homogenization step, from which it can be concluded that the deformation has considerable effects on the mechanical properties and shape-memory characteristics of Ti-based SMAs. The microstructure of homogenized and deformed Ti-23 at% Nb SMAs consists of β, α, α′ and ω phases, while the sintered sample shows only β and α phases. Endothermic and exothermic peaks of the austenite ↔ martensite transformation are seen in the homogenized sample, then after being deformed, the exothermic peak disappeared. The highest austenite start and finish temperatures were observed with the deformed sample due to disappearance of TiNb 4 intermetallic compounds and a high percentage of β phase. The ductility of the deformed sample shows the highest value compared with the homogenized sample due the elimination of coarse α precipitates and brittle intermetallic compounds of TiNb 4 , along with the suppression of the brittle ω phase and retaining β matrix. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To reach the upper thoracic vertebrae, a number of extensive approaches have been proposed. The purpose of this study is to provide a clear perspective for the selection of surgical approaches in patients who undergo vertebral body resection, reconstruction, and stabilization for upper thoracic and cervicothoracic junction instabilities. Methods: Seventeen patients with upper thoracic or cervicothoracic junction (C7-T6) instability underwent surgery between January 1999 and May 2004. All patients presented with pain and/or neurological deficits. The causes of instabilities were 10 traumas and 7 pathological fractures. The approach chosen was primarily dictated by 3 factors including (1) type of injury, (2) level of lesion, and (3) time of admission. Ventral surgical approach was performed to all pathological and traumatic fractures causing anterior spinal cord compression. Level of lesion determined the selection of the type of ventral surgical approach, namely, supramanubrial, transmanubrial, or lateral transthoracic. On the other hand, combined (anterior and posterior) approach was performed to all late admitted trauma patients. Results: Twelve anterior, 2 combined (anterior and posterior), and 3 posterior approaches were performed in this study. Anterior approaches included 3 transmanubrial, 5 upper lateral transthoracic, and 4 supramanubrial cervical dissection procedures for decompression, fusion, and plate-screw fixation depending on the levels of the lesion. The mean follow-up period was 18 months, ranging from 10 to 58 months. Nonunion or instrument-related complications were not observed. The postoperative neurological conditions were statistically significantly better than the preoperative ones (P = .003). Conclusion: Consideration of the type of injury, level of lesion, and time of admission can provide a perspective for the selection of side of surgical approach for this transitional part of the spinal column. This study also suggests that supramanubrial cervical approach achieves sufficient exposure up to T2, transmanubrial approach for T3, and lateral transthoracic approach below T3. [Copyright &y& Elsevier]