Microtexture Analysis of the Alumina Scale in Thermal Barrier Coatings

Transmission electron microscopy‐based grain orientation mapping method was employed to investigate the microtexture of the alumina scale formed in commercial thermal barrier coatings (TBCs) with two standard types of Pt‐enriched bond coats. Reliable orientation/phase maps with a spatial resolution down to 2 nm were acquired on the alumina grains. It was observed that the alumina scale on the Pt‐aluminide β‐phase bond coat has a stronger c‐axis texture normal to the bond coat surface, in comparison with that on the Pt‐diffused γ/γ′‐phase bond coat. The microtexture of the alumina scale could affect its effective coefficient of thermal expansion, which is a contributor to the severity of the bond coat rumpling mechanism of TBCs failure.     

Optimizing Approach of Water Allocation to Off-Takes During Reduced Flows

Multi-objective optimization models with an index were developed based on farmers’ preferences, local requirements, supplies available at the head of the canal, system losses, crop demand about different growth stages, and field soil moisture balance. The models were applied using linear programming. The Model 1 determines the cropping pattern by maximizing net economic benefits using a monthly basis lumped volume available at the head of the canal and is set to the minimum and maximum area constraints along with the constraint of minimum main crop area. The areas for different crops given by the first model form input for the Model 2. The other inputs of Model 2 included periodic supply available at the head of the primary canal (7-day period in this study), root growth depth, demand, and soil moisture constants. The Model 2 optimizes the sum of relative yields of all the crops and provide the irrigation levels of various crops for specified periods. Finally, the distributed area and irrigation levels determined by Model 2 are used in conjunction with the losses to decide flow rates of off takes. The complete program was implemented in the West branch irrigated area of Mirpurkhas subdivision. The results showed that the resources were allocated to off-takes in a competitive and conflict-free manner.

     

Dynamic Similarity of Six Bar Ball Tensegrity Structure in Compression and Expansion Processes

Tensegrity structures have identical members in an orientation that have correlated dynamics under external force. To study this interdependent dynamics in different members in compression and expansion processes, it is vital to analyze the dynamics of the whole structure. In this study, six bar tensegrity structure was studied under compression and expansion, and interdependent movement of different members of the structure in both processes was obtained. First, the relationship between external force and members force densities was analytically developed based on the assumption that each bar moves with the same distance when an external force is applied on the six bar tensegrity ball structure along one plane that either compresses or expands the structure. Then, two individual simulations were carried out to analyze the movement of each bar in compression and expansion under the effect of external force, and elongation in all strings was studied in both processes. Finally, comparative dynamic study of different members in compression and expansion of the structure with the effect of external force was performed, which were categorized according to dynamic symmetry.     

Managing Saline Water Intrusion in the Lower Indus Basin Aquifer

In view of the declining surface water sources for irrigated agriculture in Pakistan, farmers are compelled to extract groundwater in order provide to security against uncertain canal supplies during critical crop growth periods. However saline water intrusion can be a major hindrance to the sustainable groundwater development. Against this background, a study was conducted with a three dimensional finite element model (FEMGWST) based on the Galerkin weighted residual method being developed to simulate groundwater flow and the saline water intrusion from underlying poor quality aquifer in response to groundwater pumping through low capacity partially penetrated wells. The model was calibrated with field data collected in the district Khairpur of the Lower Indus Basin. The stability of the model for transient groundwater flow and solute transport against different time marching schemes were evaluated. This study showed that the explicit and the Crank-Nicolson time marching schemes developed the numerical oscillating, the global error and the convergence problem. The calibrated model was applied to predict the impacts of different well configurations on the pumped water quality and on the development of saline water mound at the bottom of the well. It was observed that the saline water intrusion into the fresh groundwater layer was directly related to the well discharge, pumping time and inversely to the thickness of fresh-saline water interface and the number of well strainers installed. The model results suggested that intermittent pumping through multi strainer wells could effectively be used to suppress the saline water intrusion. However multi strainers wells were found to induce saline water intrusion when the thickness of fresh-saline water interface was reduced to 4 m.     

Online Banking Information Systems Acceptance: An Empirical Examination of System Characteristics and Web Security

Prior work on the technology acceptance model (TAM) is mainly devoted to the influence of TAM’s core motivational factors and their impact on behavioral intent toward IS acceptance. Relatively little research has focused on what specific system design characteristics motivate individuals toward IS acceptance. This article identified specific systems design factors and examined their impact on TAM’s motivational factors through the TAM. The findings will help designers to design and implement better user-accepted systems.     

The nexus between misallocation of land resources and green technological innovation: a novel investigation of Chinese cities

Clean Technologies and Environmental Policy - As an important production factor, land resources significantly impact green technology innovation. However, the misallocation of land resources caused...     

Big-Data Processing Techniques and Their Challenges in Transport Domain

This paper describes the fundamentals of cloud computing and current big-data key technologies. We categorize big-data processing as batch- based, stream- based, graph- based,DAG-based, interactive-based, or visual-based according to the processing technique. We highlight the strengths and weaknesses of various big-data cloud processing techniques in order to help the big-data community select the appropriate processing technique. We also provide big data research challenges and future directions in aspect to transportation management systems.     

Synthesis,Characterization, and Exploration of Antimicrobial Activity of Copper Complex of Diamide Derivative of p-tert-butylcalix[4]arene

Calixarenes are a versatile class of compounds, which possesses wide applications in various fields including biological as well as pharmaceutical sciences. In the present study, amide derivative of calix[4]arene (3) was synthesized and characterized by modern analytical techniques such as elemental analysis and Fourier transform infrared spectroscopy (FT-IR). Complexation property of 3 with essential metals was explored by UV-Vis spectroscopy. The results revealed that 3 shows good selectivity toward Cu²⁺. Job's plot analysis suggests that 3 forms complex with Cu²⁺ in 1:2 stoichiometric ratio. Antimicrobial activity of 3 and its Cu²⁺ complex was also determined and it was observed that 3 is more efficient against R. stolonifer as compared to its action against bacteria, because for fungus it shows “Minimum Inhibitory Concentration” (MIC) value equal to 1.5 µg/mL, while for bacteria MIC is 3 µg/mL. However, it was found that complex is more efficient in action than 3. Oxidation state of metal, overtone concept, and Tweedy's chelation theory justifies the increased activity of metal complex. Cu²⁺ complex shows higher antimicrobial activity toward Escherichia coli (E. coli) (Gram-negative) bacteria by showing MIC value 0.37 µg/mL. While for Staphylococcus albus (S. albus) (Gram-positive) bacteria and Rhizopus stolonifer (R. stolonifer) fungal species, it shows MIC value equal to 0.75 µg/mL.