Enhancing Droplet Quality of Edible Ink in Single and Multi-Drop Methods by Optimization the Waveform Design of DoD Inkjet Printer

The multi-drop method with a good droplet quality is a big challenge in inkjet technology. In this study, optimization of Drop on Demand (DoD) inkjet printer waveform design was conducted. The effectiveness of the waveform design, so-called W waveform, from previous study as a preliminary vibration for the multi-drop ejection method was investigated. The unmodified W waveform was proven not to be an effective waveform for lower viscosity of liquid, especially when compared by the standard waveform obtained from a print-head manufacturer. Edible ink with a viscosity below the optimum range for print-head specifications was employed as the operating liquid. The preliminary vibration W waveform was modified to improve the droplet quality of the edible ink. It was proven that a 40% adjusted voltage of the rear wave of the W waveform was effective as the optimum waveform design for edible ink. The droplet quality of the multi-drop ejection method for grey-scale technology was improved by optimizing the W waveform design.

Simulation of radial oscillations of a spring-loaded roll in a roll compactor

Carried out simulation of oscillations of a spring-loaded roll in a roll compactor when interacting the powder being compacted with the rolls. Considering the separation of the feed and compaction areas in the contact area of the roll with the material being compacted, we obtain the dependence of the force acting on the roll on the gap size between the rolls. It is shown that this dependence is non-linear, and it can be described with a sufficiently high accuracy degree by an exponential function with a negative exponent in the working range. The given numerical solution of the equation of free nonlinear oscillations of the spring-loaded roll has shown that considering the deformation of the material being compacted leads to a reduction of the natural frequency of the system by 20–25 % compared to the case, where the pressure force of the powder on the roll is assumed to be independent of the gap size. The nonlinearity of the dependence of the pressure force on the gap also leads to the increase by 10 % in the calculated values of the maximum displacements. The developed approach to the calculation of oscillations of the spring-loaded roll in the roll compactor enables to take into account the peculiarities of deformation of the powder being compacted during its interaction with the rolls. In addition, it allows estimating the frequencies and oscillation amplitudes and setting the optimum range of spring rate values, at which the occurrence of resonance in the machine is not possible.

Examine the optimal position of controls and display in computer numerical control machines

In Engineering Industries suffering due to industrial wound and ill health, of the Computer Numerical Control machines operators are in the increasing trend, in the subjective analysis which we carried out for the CNC machine, the operators expressing the discomfort at the neck, upper back, lower back, shoulder, and arm because of working with the keys in the controls and viewing the display. The aim of this examination is to identify the most favourable location of control and display through various muscles that activate while performing in CNC machine operations. We introduce surface Electromyogram (EMG) to determine the muscle activity and deliberate on plane of the body close to respective muscles of an operator.The muscle activity measured for all the twenty subjects, at five different levels to find out the best optimal location for controls and display to establish the findings of the subjective study. Though there is no clear trend when all the subjects are aggregated, it is seen that 90 cm-100 cm be the optimum range for the midpoint of the control panel and 143cm-148 cm appears to be the optimum range for the midpoint of the display. Since changes in muscle activity are comparatively small for all the six muscles taken for study, however, the effect of cumulative activity borne over a shift, week, month, and year are to be considered. Muscle activity may increase in repetitive head/finger movements. These combined effects are to be captured for the ergonomic design of the CNC operator interface.

Temperature Effect on Seed Germination Performance of a Local Variety of Onion in Bangladesh

Seed germination performance test of Taherpuri onion (a local variety of onion) under six different temperatures (15, 20, 25, 30, 35 and 40°C) was the main goal of this experiment. Germination percentage (GP) was calculated at highest 60.25% at 25°C, and the highest germination rate 20.08 was observed in the same temperature condition. The lowest germination performance (13.25 % germi-nation and 3.32 seeds per day as germination rate) was found at 40°C temperature. Finally, the authors mentioned the temperature 20 to 30°C as optimum range, and suggested the temperature 25°C as best suited for obtaining highest results in case of both germination percentage and germination rate of these seeds. To produce maximum seedlings of the local variety of onion, the mentioned temperature should be followed by the local farmers.

Simulation Methods Development for an EV Battery Pack in Terms of Thermal and Safety Aspects

This paper is the representation of our effort at modelling a LiFePO4 battery pack for an electric vehicle (EV) and further carrying out simulations on it. The process involves creating a single cell and then making a combination of these cells to form a battery pack. The simulations assist us in monitoring the thermal behaviour of the 60Ah battery pack after working for a stipulated amount of time at 1 and 2 C rates. It can be observed that the battery pack may experience thermal shock or thermal runaway leading to the failure of battery pack. Hence it is of paramount importance that we keep a check on the temperature range of the battery. The pack functions best when its temperature is maintained in the range of 288K-308K. This is a challenge in the absence of cooling. Hence, we used air and PCM (RT15 & RT31) as coolants to accomplish the objective of maintaining the temperature of battery pack within the optimum range.

COMPARATIVE STUDY OF SEVEN BRANDS OF LEVOFLOXACIN 500 MG FILM-COATED TABLET MARKETED IN YEMEN

Objective: The objective of the current study was to evaluate the quality control parameters of seven brands of levofloxacin 500 mg film-coated tablet available in the Yemeni market. Methods: Physicochemical parameters assay was performed for seven brands of levofloxacin 500 mg film-coated tablet. Each brand was subjected to official and unofficial in vitro quality control tests, including weight variation, thickness, hardness, friability, disintegration, dissolution, and content uniformity assay by High-Performance Liquid Chromatography (HPLC). Results: Out of seven, six brands of levofloxacin 500 mg film-coated tablet passed official specified assay tests according to the United States Pharmacopeia (USP) specifications. They showed a similar profile of thickness ranged between±0.01 and 0.10%, friability ranged between 0.01% and 0.34%, disintegration time ranged between 3.00 and 15.00 min, dissolution percentage ranged between 90.650 and 103.05 and content uniformity ranged between 93.62 and 107.12%. Regarding weight variation and hardness, six brands passed the weight variation test and only three brands showed optimum range (10-20 kg) of hardness test. Only one brand failed to pass the weight variation test, and four brands failed to pass the optimum range (10-20 kg) of hardness. Conclusion: There are no remarkable differences between the seven brands regarding in vitro quality control tests of content uniformity, thickness, friability, disintegration, and dissolution. Even though four brands were above the optimum range of hardiness, they showed complete disintegration and dissolution within the acceptable limit. Regular assessment of marketed drugs is required to ensure bioequivalent to their innovators.

CHEMICO-BIOLOGICAL INTERACTION OF SELECTED TETRAHYDROPYRIMIDINES

Tetrahydropyrimidines (THPMs) attracted attention as a very important class of aza heterocycles with broad pharmacological activities during the past years. In many studies have been proven that THPMs have anticancer, anti-inflammatory, antimicrobial, antioxidant, antifungal, anti-HIV activity. Bearing in mind our interest in medicinal and Biginelli chemistry, we investigated interaction with important biomacromolecules (DNA, BSA) and our earlier synthetized THPMs derivatives with proven very good cytotoxic activity.[1] Investigation of affinity of compounds A and B (Figure 1) to bind to bovine serum albumin (BSA) is based on the fact that the efficiency of drugs depends on their ability to bind for carrier protein. Binding properties were investigated by using the fluorescence emission titration of BSA with A and B. The obtained values of Ka, which are in optimum range which is considered to be 106-107M-1 indicate that both compounds have great ability to bind to BSA. In addition, Ka values for A-BSA and B-BSAshow that both compounds are suitable for drug-cell

Assessment of Salts Effect in Sugar-aqueous System

In the present study, the preferential salvation of salts in sugar-aqueous systems has been considered. It is carried out by using conductometric observation of analytical grade sugar and plantation white sugar aqueous system with salts viz. CaCl2, MgCl2, KCl, NaCl. It shows that the conductivity is in a linear relationship with the electrolytes and non-sugar present in both analytical grade sugar and plantation white sugar over a range of 5 to 25 W/V percent. The optimum range of concentration found to be for both the sugars is about 20%. Encouraging results could be obtained in the determination of sugars i.e. non-electrolytes and electrolytes in aqueous sugar solution products. The present study shows valid technological interest to understand the Maillard reaction due to the adoption of MgCl2 salt in place of sulphite. These sugars–salts complexes are responsible for the formation of molasses which leads to substantial loss of sugar of around ten percent of the total sugar present in cane.