Different Durations Of Time Research Articles

Economic order quantity model with production plan for sequentially convertible item

An economic quantity and production plan is developed for sequentially convertible items for deteriorating items. The initial form of an item sequentially converts into another form and different nature of items. In this process conversion cost and times need to convert the item. We have considered that demand of an item is different for different converted items, also the deterioration rates are different. For example, milk is converted into curd, curd into butter and butter into ghee after different durations of time. Managerial insights are provided for convertible items. Conversion of items needs conversion cost and conversion time.

EVALUATION OF BOTANICALS AND FUNGICIDES AGAINST SEED BORNE FUNGI AND GERMINATION OF ROUGH LEMON SEEDS

Citrus fruits are grown all over the world, including Pakistan. However, the poor storage conditions for citrus seeds in tropical and sub-tropical regions compromise their viability during growth. In this study, M. olifera (Moringa) and A. niger (Neem) leaves were used as seed coating agents and were utilized for the first time without any deep treatment of such leaves with an objective to reduce the cost of botanical fungicides and to control the harmful effects of synthetic fungicides. Topsin-M, a synthetic fungicide, was used as a reference compound to compare the results of fungicides from botanical sources than that of a traditionally available synthetic fungicide. Three different concentration of fungicide solutions (C1, C2 and C3), that were coated on the surface of seeds for different duration of time (8, 10 and 12h), were prepared. It was observed that the coating of seeds with fungicides, either botanical or synthetic, significantly improved the horticultural (germination %age and number of days required for germination) and pathological (fungi %age and number of contaminated seeds) parameters of rough lemon, as compare to control or non-coated seed samples. It is expected that the findings of this study will promote the use of botanicals as seed coating agent as they are readily available to famers and are also acceptable for the cultivation of organic crops.

A comparison of reproduction of adult Microtus fortis after existing under different density in different durations of time

A comparison of reproduction of adult Microtus fortis after existing under different density in different durations of time

Gafchromic XRQA-2 film for Strontium-90/Yttrium-90 (Sr-90/Y-90) Detection

Gafchromic XRQA-2 radiochromic film is an effective tool for quality assurance and dose assessment in kilovoltage radiotherapy and diagnostic applications. This work is done to study the response of Gafchromic XRQA-2 film for beta particle detection. Materials investigated are the beta particle source, Sr-90/Y-90 and Gafchromic XRQA-2 film. The film is exposed to Sr-90/Y-90 for different duration of time and scanned with flatbed scanner. The film is analyzed by using a ImageJ software in the red mode. The result shows that the net reflected optical density (Net ROD) increased linearly with increase in time. The Net ROD and time integrated specific surface activity increased linearly with time. The Net ROD for Sr-90/Y-90 is from 0.00 to 0.13. Thus, the Net ROD is highly related to the duration of time exposed to the beta source.

Static and dynamic signatures of anisotropic electronic phase separation in La2/3Ca1/3MnO3 thin films under anisotropic strain

The electronic phase separation (EPS) of optimally doped ${\mathrm{La}}_{2/3}{\mathrm{Ca}}_{1/3}\mathrm{Mn}{\mathrm{O}}_{3}$ (LCMO) thin films under various degrees of anisotropic strain is investigated by static magnetotransport and dynamic relaxation measurements. Three LCMO films were grown simultaneously on (001) $\mathrm{NdGa}{\mathrm{O}}_{3}$ substrates by pulsed laser deposition, and then postgrowth annealed at $780{\phantom{\rule{0.16em}{0ex}}}^{\ensuremath{\circ}}\mathrm{C}$ in ${\mathrm{O}}_{2}$ for different durations of time. With increasing annealing time, the films developed significant strains of opposite signs along the two orthogonal in-plane directions. The static temperature-dependent resistivity, $\ensuremath{\rho}(T)$, was measured simultaneously along the two orthogonal directions. With increasing annealing time, both zero-field-cooled and field-cooled $\ensuremath{\rho}(T)$ show significant increases, suggesting strain-triggered EPS and appearance of antiferromagnetic insulating (AFI) phases in a ferromagnetic metallic (FMM) ground state. Meanwhile, $\ensuremath{\rho}(T)$ along the tensile-strained [010] direction becomes progressively larger than that along the compressive-strained [100]. The enhanced resistivity anisotropy indicates that the EPS is characterized by phase-separated FMM entities with a preferred orientation along [100], possibly due to the cooperative deformation and rotation/tilting of the $\mathrm{Mn}{\mathrm{O}}_{6}$ octahedra under the enhanced anisotropic strain. The anisotropic EPS can also be tuned by an external magnetic field. During a field cycle at several fixed temperatures, the AFI phases are melted at high fields and recovered at low fields, resulting in sharp resistance changes of ratio as high as ${10}^{4}$. Furthermore, the resistivity was found to exhibit glasslike behavior, relaxing logarithmically in the phase-separated states. Fitting the data to a phenomenological model, the resulting resistive viscosity and characteristic relaxation time are found to evolve with temperature, showing a close correlation with the static measurements in the EPS states.

UTILIZATION OF FOUR SUDANESE WILD FRUITS TO PRODUCE NECTARS

Doum (Hyphaene thebaica L), kirkir (Randia geipaeflora), karmadoda (Naucleae latifolia) and godeim (Grewia tenax) are some of the indigenous fruits in Sudan. The aim of this investigation is to process nectars from the edible part of these fruits. Doum and kirkir fruits were soaked in water in variable ratios for different durations of time to obtain the highest total soluble solids, total solids and total extractable matter. The pulps of karmadoda and godeim fruits were obtained mechanically by adding water, blanching and pulping with pulper machine. Results showed that soaking of doum and kirkir fruits at ratios 1: 4/2 h and 1: 4/8 h, respectively, were the most appropriate methods for extraction. The total solids (TS) obtained were 10.61 and 10.32 %, total soluble solids (TSS) 10.50 and 9.50%, and the total extractable matters (TEM) were 26.06 and 23.69%, respectively. However, blanching karmadoda fruit in water at a ratio of 1: 2/10 min gave total solids of 5.63% and total soluble solids of 5.00%. The nectars made were subjected to organoleptic evaluation. The results suggested that processing of nectars from forest fruits by direct extraction gave excellent sensory characteristics for human consumption.

Optical dynamic range maximization for humidity sensing by controlling growth of zinc oxide nanorods

An experimental study of the dynamic range maximization with Zinc Oxide (ZnO) nanorods coated glass substrates for humidity and vapor sensing is reported. Growth time of the nanorods and the length of the coated segments were controlled to study the differences between a reference environmental condition (normal humidity or dry condition) and water vapor concentrations. In order to achieve long dynamic range of detection with respect to nanorods coverage, several substrates with triangular patterns of ZnO nanostructures were fabricated by selective hydrothermal growth over different durations of time (5 h, 10 h and 15 h). It was found that maximum dynamic range for the humidity sensing occurs for the combination parameters of normalized length (Z) of 0.23 and normalized scattering coefficient (ζ) of 0.3. A reduction in transmittance by 38% at humidity levels of 80% with reference point as 50% humidity was observed. The results could be correlated to a first order approximation model that assumes uniform growth and the optimum operating conditions for humidity sensing device. This study provides an option to correlate ZnO growth conditions for different vapor sensing applications which can set a platform for compact sensors where modulation of light intensity is followed.

Oil Aging due to Partial Discharge Activity

Oil is the main insulation in power transformers and over long time of ageing its insulation properties can change. In this paper ageing of oil due to the exposure to electric discharges was investigated. The effect of high energy discharges (complete arc) and low energy discharges (partial discharges) on oil properties such as breakdown strength and oil conductivity was investigated.An experimental setup consisting of two spherical electrodes was designed. The adjustable distance between the two electrodes made it possible to have PD with different magnitude.The oil conductivity and breakdown strength was measured for three sets of experiments. The first group of experiments was performed on new oil in order to have a reference for comparison. In the second group of experiments the new oil samples was exposed to 1000 and 3000 lightning impulses. In the third group of experiments new oil samples was exposed to partial discharge for different duration of time. Oil conductivity and breakdown strength of these aged samples were compared with new oil. The results show that after exposure to lightning impulse oil conductivity increases and breakdown strength decreases, However PD activity for short time does not change the oil conductivity but it reduces the breakdown strength.

The quest for safer antithrombotic treatment regimens in patients with coronary artery disease: new strategies and paradigm shifts

ABSTRACTIntroduction: Despite the undeniable benefits on reducing ischemic adverse events, antiplatelet regimens including dual antiplatelet therapy (DAPT) with aspirin and P2Y12 receptor inhibitors are associated with an increased risk of bleeding. The awareness of the unfavorable prognostic implications associated with bleeding complications have somewhat hampered the enthusiasm towards the use of more potent antiplatelet treatment regimens or prolonged use of DAPT. This awareness also has prompted a series of investigations geared towards the identification of antithrombotic treatment regimens which are efficacious at reducing ischemic recurrences while also safe in terms of bleeding risk profile.Areas covered: The present manuscript focuses on new approaches for improving the safety profile of antithrombotic treatment regimens, including most recent updates from clinical trials, as well as future perspectives in the field.Expert commentary: Results of ongoing trials testing new antithrombotic treatment regimens, including new drugs, new combinations, which may be used for different duration of time according to the individual’s risk of thrombotic and bleeding complications, may lead to paradigm shifts in secondary prevention of atherothrombotic events in patients with coronary artery disease.

Phase transformation kinetics in rolled U-10 wt. % Mo foil: Effect of post-rolling heat treatment and prior γ-UMo grain size

The effect of sub-eutectoid heat treatment on the phase transformation behavior in rolled U-10 wt.% Mo (U10Mo) foils was systematically investigated. The as-cast 5 mm thick foils were initially homogenized at 900 °C for 48 h and were hot rolled to 2 mm and later cold rolled down to 0.2 mm. Three starting microstructures were evaluated: (i) hot + cold-rolled to 0.2 mm (as-rolled condition), (ii) hot + cold-rolled to 0.2 mm + annealed at 700 °C for 1 h, and (iii) hot + cold-rolled to 0.2 mm + annealed at 1000 °C for 60 h. Annealing of as-rolled materials at 700 °C resulted in small grain size (15 ± 9 μm average grain size), while annealing at 1000 °C led to very large grains (156 ± 118 μm average grain size) in rolled U10Mo foils. Later the samples were subjected to sub-eutectoid heat-treatment temperatures of 550 °C, 500 °C, and 400 °C for different durations of time starting from 1 h up to 100 h. U10Mo rolled foils went through various degrees of decomposition when subjected to the sub-eutectoid heat-treatment step and formed a lamellar microstructure through a cellular reaction mostly along the previous γ-UMo grain boundaries. The least amount of cellular reaction was observed in the large-grain microstructure at all temperatures. Conversely, a substantial amount of cellular reaction was observed in both the as-rolled and the small-grain microstructure. After 100 h of heat treatment at 500 °C, the volume fraction of the lamellar phase was found to be 4%, 22%, and 82% in large-grain, as-rolled, and small-grain samples, respectively.

Barrier Heights of Au on Diamond with Different Terminations Determined by X-ray Photoelectron Spectroscopy

Barrier heights of Au on hydrogen-/oxygen-/fluorine-/nitrogen-terminated diamond (H-/O-/F-/N-diamond) have been investigated by X-ray photoelectron spectroscopy. All of the H-/O-/F-/N-diamond surfaces have been formed on different areas of one diamond sample. An Au film with a thickness of 4 nm was evaporated to form Au/diamond contacts. Barrier height values for Au on H-/O-/F-/N-diamond contacts were determined to be −0.19, 1.71, 2.29, and 2.39 eV, respectively. Then, the surface of Au/diamond contacts was treated by 1000 eV Ar+ bombardment with different duration of time, resulting in a pinned barrier height of 1.83 eV independent of contact structures. In the end, the spatial distribution of the energy band diagram has been calculated by solving Poisson’s equation.

Surface Quality of Planed Beech Wood (Fagus sylvatica L.) Thermally Treated for Different Durations of Time

Thermally treating wood improves its dimensional stability and durability. The chemical changes brought about by a heat treatment also affect the mechanical properties of wood. Consequently, a heat treatment also influences how a wood surface responds to machining. This study examined the impact of heat treatments at 200 C between 1 h and 6 h on the subsequent surface quality of planed beech wood (Fagus sylvatica L.). The new approach was that surface quality was assessed by following a tested method from previous research regarding the measuring and evaluation recommendations meant to reduce the biasing effect of wood anatomy, Also, a large number of roughness parameters were used for interpretation of the combined effect of processing and wood anatomy after filtering the data with a robust filter. Among those, Rk is the parameter that is least biased by wood anatomy and that best expresses the effect of processing alone. Electron micrographs were taken to visually assess the resultant surfaces. The results showed a gradual increase in processing roughness, as distinctively measured by Rk, which increased with longer durations of the treatment. Vessel cavities were deeper than those caused by processing and that influenced, among other parameters, Ra, which is most commonly used in literature to assess surface quality. The ray tissue, especially, exhibited both greater pull-out of fibers and a sort of plasticization with increased treatment time. The length of the thermal treatment reduced surface waviness. The results also showed that it was necessary to calculate the roughness parameters to differentiate between two similar surfaces rather than relying on visual and tactile assessments alone.

Effects of drainage duration on mineral wetland soils in a Prairie Pothole agroecosystem

Recent flooding of agricultural land in the northern Prairie Pothole Region – coupled with intensification of agriculture – has resulted in renewed efforts to drain Prairie Potholes. Drainage is used to improve growing conditions and increase the amount of land that can be cultivated. The aim of this study was to determine if duration of agricultural drainage improved growing conditions and nutrient availability, by measuring physical (i.e. structure and bulk density) and chemical properties (i.e. C, N, and P). Forty-two wetlands and paired midslopes were selected in the Prairie Pothole Region in the Black soil zone of southeastern Saskatchewan. Drainage duration of wetlands ranged from 0 to 50 years. Results suggest drainage does improve growing conditions and nutrient availability for agricultural production, but these changes vary across wetlands drained for different durations of time. Compared with undrained soils, changes were greatest in soils drained from 20 to 34 years, but decreased after 36 years becoming more similar to cultivated midslope positions. Some drainage benefits include increased nitrification and greater available PO4−3 at a depth of 0–15cm. Phosphorus sorption decreased with drainage duration and P desorption increased in soils drained from 7 to 34 years. This could result in greater available N and P for crop uptake, but could also lead to greater nutrient losses. Additionally, bulk density increased and microaggregates decreased with drainage duration. Compared with undrained soils, drainage did not have a significant effect on macroaggregates, soil organic carbon, water extractable organic carbon, light fraction, total N, NO3− , and mineralization. It is likely other agricultural practices used in conjunction with drainage, such as tillage, fertilizer additions, and crop removal, are affecting how these soil properties change over time. The resulting quantitative data from this study provides an excellent resource for planning management strategies to improve nutrient use efficiency and reduce losses to the environment.

Factors Influencing the Direct Electrochemical Reduction of Nb2O5 Pellets to Nb Metal in Molten Chloride Salts

Powder compacted and sintered Nb2O5 pellets were cathodically polarised against graphite anode in calcium chloride melt at 1173 K to study the influence of various factors on the electrochemical reduction of the oxide. The parameters were; duration and temperature of electrolysis, open porosity of pellets, nature of anode, mode of electrolysis and configuration of the oxide cathode. The experiments were also conducted in KCl, KCl-25 mol% CaCl2 and NaCl melts to understand the effect of melt composition on the electroreduction. Different Ca–Nb–O and Nb–O intermediates were found in the pellets electrolysed for different durations of time in CaCl2 melt which eventually reduced to Nb. The current efficiency of the process decreased with increasing duration of electrolysis. Decrease in electrolysis temperature from 1173 to 1073 K led to the decrease in the rate of reduction of the oxide pellets. Pellets with high open porosity reduced faster. Carbon contamination of the melt was relatively less when pyrolytic graphite was used as anode. Of all the melts studied, the reduction was found to be better in calcium chloride melt, that too when alumina crucible was used as container of the melt.

Effect of reinforcing particles on hydrolytic degradation behavior of poly (lactic acid) composites

Abstract In this study, degradation behavior of polylactic acid (PLA) composite reinforced with different types of particles (titanium dioxide, multi-walled carbon nanotubes, surface-treated multi-walled carbon nanotubes, and graphene nanoplatelets) were investigated. Samples were prepared by extrusion and injection molding. Hydrolytic degradation was induced by immersing the specimen in a sodium hydroxide solution. Particles can affect the crystallization kinetics of PLA matrix which may affect the degradation behavior. In order to examine the crystallization kinetics and crystallinity of PLA matrix, differential scanning calorimetry and X-ray diffraction measurements were employed. Annealing was done for different durations of time in order to control the crystallinity of the matrix. The results show that the crystallization rate was remarkably increased due to the addition of particles and that there was an optimal concentration of particles. The degradation rate of most of the PLA composites was faster than that of neat PLA, indicating that the interface between the particle and the PLA matrix was not perfect. Meanwhile, the degradation rate of PLA reinforced with multi-walled carbon nanotubes became slower due to increased crystallinity.

Effect of addition of water-soluble salts on the hydrogen generation of aluminum in reaction with hot water

Aluminum powder was ball milled for different durations of time with different weight percentages of water-soluble salts (NaCl and KCl). The hydrogen generation of each mixture in reaction with hot water was measured. A scanning electron microscope (SEM) as well as energy-dispersive spectroscopy (EDS) were used to investigate the morphology, surfaces and cross sections of the produced particles. The results show that the presence of salts in the microstructure of the aluminum considerably increases the hydrogen generation rate. At shorter milling times, the salt covers the aluminum particles and becomes embedded in layers within the aluminum matrix. At higher milling durations, salt and aluminum phases form composite particles. A higher percentage of the second phase significantly decreases the milling time needed for activation of the aluminum particles. Based on the EDS results from cross sections of the milled particles, a mechanism for improvement of the hydrogen generation rate in the presence of salts is suggested.

Direct Carburization of Tungsten Trioxide by Mechanical Alloying

Tungsten carbide is the choice of predilection for producing parts requiring good wear resistance. In this context it is produced in large quantities by the carburization of tungsten trioxide under a stream of hydrogen at elevated temperature followed by grinding to achieve the required fineness. This work aims to study the conditions in which tungsten carbide can be produced by mechanical alloying method. Using this method would facilitate obtaining carbide through a simple and easy to use technology without prohibitive costs, directly by an end user. For this purpose the thermodynamic study is conducted to establish the conditions under which the carburizing reaction can take place. The condition for the reaction to occur spontaneously is reaching a temperature of 621°C. Carrying out this reaction in a system without external energy input seems impossible. Mechanical alloying experiments were carried out in a Fritch Pulverisette 7 premium line planetary mill, equipped with two bowls of 80ml capacity lined with sintered tungsten carbide. Each bowl contained 200 g of tungsten carbide balls with dimensions of 10 mm and 12 mm. The balls/load ratio was 10:1. Grinding was performed in steps of 3 hours, with breaks for sampling, with rotation speeds of 600 and 800 rpm. Tests conducted showed complete conversion of raw materials into tungsten carbide after different durations of time.

EFFECT OF WET TROPICAL WEATHERING ON THE STRENGTH OF SANDSTONE

The influence of moisture content to the strength of wet tropically weathered sandstone of Jurong Formation found in Nusajaya, Johor was studied. The rock materials have been affected by weathering action; hence the alteration of its engineering properties is incontestable due to these effects. A total of 36 samples representing various weathering grades were collected from the field and tested at various moisture content by immersing them in water at different duration of time, ranging from 15, 30 and 60 minutes. Point load tests for the determination of the strength index Is(50) of the rock were then carried out. For weathered sandstone (Grade II to IV), the mean initial moisture content ranges from 0.15% to 11.00% respectively, while the initial mean strength index has maximum and minimum values of 7.76 MPa and 0.38 MPa. The results reveal that there is a significant relationship between the weathering grades, moisture absorption and strength. The moisture absorption is dependent on the amount of clay minerals present in the rock material, which indirectly affects the strength, as observed with the increment of weathering state. In conclusion, this study indicates that sandstone with higher moisture content and increase in weathering grade exhibits lower strength values.

The study of air-plasma treatment on corn starch/poly(ε-caprolactone) films

In spite of usefulness of synthetic polymers in every aspects of life, the environmental hazards limit their use. Starch based biodegradable polymers is one of the solutions to it. Packaging has a major share in use of synthetic polymers. For packaging application, it is necessary to have good surface and barrier properties of the material. Plasma surface modification of materials is a promising solution to enhance surface properties. In the present paper, cornstarch/poly(ε-caprolactone) (CSPCL) films were treated in air-plasma for different durations of time. The effect of air-plasma treatment on surface properties and biodegradation was studied. The extent of etching was evaluated from weight change (%) study. Changes in surface chemical composition were analyzed using ATR-FTIR and XPS. The contact angle and surface free energy (SFE) study indicate that air-plasma treatment leads to hydrophilization of CSPCL films. The changes in surface topography of plasma processed films were analyzed using AFM and SEM. The roughness caused by etching and increase in surface free energy facilitates the improvement in adhesive properties like printability and peel strength. Changes in barrier properties were studied using water vapor and oxygen transmission rate. Effect of air-plasma treatment on biodegradation of treated and untreated samples was studied by simulating natural biodegradation conditions in a controlled environment using indoor soil burial method and with a single bacterial system comprising of a commonly occurring soil bacterium, Bacillus subtilis MTCC 121. While the soil system is indicative of biodegradation due to macro as well as micro elements, a single microbial system will identify the interaction between the microorganisms and modified surface thus showing the effect of air-plasma treatment on the degradation process. Biodegradation by indoor soil burial method was assessed by measuring loss in tensile properties and growth of soil micro flora on surface by optical light microscopy (OLM). Biodegradation by B. subtilis was assessed by measuring increase in its number along with the changes it brought about in the sample surface by optical light microscopy and SEM. It was observed that such surface modifications enhanced the biodegradation rate along with finding application in packaging field, thus providing a green solution for the increasing packaging utilization and addressing environmental concerns.

High pressure destruction kinetics along with combined effect of potassium sorbate and high pressure against Listeria monocytogenes in Indian white prawn muscle

High hydrostatic pressure treatment not only inactivates the pathogenic and spoilage microorganisms present in the food but also preserves its sensory and organoleptic characters and nutrient value. In this study, the high-pressure destruction kinetics of an important food-borne pathogen Listeria monocytogenes ATCC 19115 was studied in Indian white prawn (Fenneropenaeus indicus) muscle. Headless muscle of prawn was artificially spiked with L. monocytogenes ATCC 19115 at the level of approximately 107 CFU/g. The spiked samples were vacuum-packed in an ethylene vinyl alcohol (EVOH) pouch and then subjected to high-pressure treatment at different pressure levels (250, 300, 350 and 400 MPa) for different durations of time. Pressure D values were estimated at different pressure levels. The pressure D values at 250, 300, 350 and 400 MPa were estimated as 34.521, 11.806, 5.92 and 5.099 min, respectively. It was observed that, even after 400 MPa pressure treatment for 12 min, the concentration of the L. monocytogenes population was found to be 3.387 Log10 CFU/g. The combination of high pressure and potassium sorbate dip treatment (in acidic pH) was found to be very useful in inactivating L. monocytogenes. Potassium sorbate (0.1 %) dip for 15 min coupled with 250 and 350 MPa pressure reduced the level of L. monocytogenes by 2.345 and 5.908 Log10 CFU/g, respectively. Thus, it can be concluded that pressure treatment alone is not sufficient enough to inactivate this pathogen in prawn muscle. The combination of potassium sorbate with high-pressure treatment is a promising approach to inactivate L. monocytogenes in Indian white prawn muscle.