Advances in Applied Science and Technology Vol. 3

Montmorillonite-silica Nanocomposite for Dye Removal from Solution

Shehu Zaccheus — 2019-06-20

Dyes are used in various industries such as pharmaceutical, cosmetic, paper, leather, food stuff, plastics, and textile etc. The dye effluents are discharged into environment by either water or land. The discharge of these effluents into the receiving environments results in hazardous health problems as most of these dyes have carcinogenic effects on the living organisms. Congo red was removed on Montmorillonite-silica nanocomposite from solution by adsorption process. The adsorption parameters studied were adsorbent dose, initial concentration and contact time. The optimum adsorption parameters were found to be 2 mg/L, 1.5 g and 40 minutes for initial concentration, adsorbent dose and contact time respectively with removal percentage of 84.10%. Pseudo first and second order kinetics were used for the studies. Pseudo second order best fit the adsorption process with R = 1 than the Pseudo first order which has R 2 = 0.933. Experimental data were best fitted by the Langmuir Isotherm with R 2 =0.9024 other than the Freundlich Isotherm, R 2 =0.568. The RL of 0.994 of the Langmuir isotherm shows the favourability of the adsorption process. The maximum adsorption capacity by Langmuir isotherm was found to be 172. 40 mg/g. The adsorption process of Congo red was carried out using Montmorilonite silica nanocomposite. From the experimental data the percentage removal of 84.10% obtained at an optimum initial concentration of 2 mg/l, an optimum adsorbent dose of 1.5 g and optimum contact time of 40 minutes. Experimental data were best fitted by the Langmuir Isotherm with R 2 =0.9024 other than the Freudlich Isotherm, R 2 =0.568. The pseudo second order kinetic with R 2 = 1 best fit the adsorption process other than the pseudo second order kinetics, R 2 =0.933. Therefore, montmorillonite-silica nanocomposite obtained from montmorillonite clay and Rice husk ash can serve as a cost-effective adsorbent in the removal of Congo red dye.

Assay of Vitamin B6 (Pyridoxine Hydrochloride) Utilizing Isocratic Reversed Phase High Performance Liquid Chromatography

Ronald Bartzatt — 2019-06-20

Aims: To demonstrate an analysis for vitamin B6 from commercial aqueous nutritional drinks and solid tablets, utilizing isocratic conditions with high performance liquid chromatography (HPLC) and UV detection at 290 nm.
Study Design: Vitamin B6 in the form of pyridoxine hydrochloride is assayed by HPLC from various samples.
Place and Duration of Study: Department of Chemistry, Durham Science Center, University of Nebraska, Omaha Nebraska from May to August 2016.
Methodology: Utilizing a reversed-phase C-18 column with eluent solvent (19% ethanol, 77% water, 4% acetic acid), the samples were prepared in sample solvent (19% ethanol, 81% distilled water). Detection of vitamin B6 was accomplished at 290 nm. Analysis of samples was done following solubilizing in aqueous conditions having ethanol at 10% to 20% (v/v). Column pressure at 1900 psig, rise time 0.1 with flow rate 1.0 mL/minute. Elution peak for vitamin B6 occurred consistently at 1.6 minutes. Nutritional samples, aqueous samples, and solid pills were prepared in aqueous solvent with various levels of ethanol.
Results: Levels of vitamin B6 detected were as low as 4.4029x10 -5 1 molar to 7.8081x10 molar. Sensitivity for vitamin B6 was highest at 290 nm. Reverse phase isocratic conditions is shown to be effective for determination of vitamin B6 in aqueous based samples. Standard curves applied are highly linear in range from zero to 7.8081x10 -4 molar (y = 112,521,145.5x + 2,818.6), having coefficient of determination (R 2 = 0.9948) with very strong positive correlation coefficient (r= 0.9974). Percent recovery of vitamin ranged from 95% to 105%. Amounts of vitamin present in drinks from same manufacturer were consistent.
Conclusion: Utilizing reversed phase column, isocratic solvent conditions with ethanol in water, and a UV detector set at 290 nm is effective for determination of vitamin B6. Ethanol-water solvent system is effective. Vitamin B6 was found in various amounts in nutritional drinks tested. Percent recovery of vitamin averaged 101% with a standard deviation of 2.4%. Pyridoxine hydrochloride was effectively assayed from aqueous samples, vitamin preparations, and vitamin tablets. The methodology presented in this study will be useful for quality control analysis for commercial production. Analysis methods for vitamin assay are a necessary objective to ensure quality control of commercial products and medicinal applications.

Improved Dual Electrothermal Microgripper based on a Chevron actuator

M. Tecpoyotl-Torres — 2019-06-20

In Micro-Electro-Mechanical Systems (MEMS) technology, there is an important interest in the characterization of devices using dynamic analysis, which is a technique to determine the dynamic behavior of a structure or component, involving time, inertia and the possibly damping of the structure. This paper is focused on the analysis and simulation of an improved dual microgripper and its components: microcantilever and chevron. In addition, a movement amplifier based on an arrangement of beams was also designed in order to improve the opening of each jaw of the top gripper.

Dual microgrippers are designed on silicon and implemented using Professional Autodesk Inventor. Top gripper is initially closed, while the down one is initially open.

The analytical response of the microgripper components was acquired with Steady-State Thermal, Static Structural, and Modal modules of Ansys Workbench Software.

The dynamic behavior, resonance frequencies for chevron actuator and dual microgrippers are presented. Simulation results show the modal shapes of all analyzed devices, determining their respective modal frequencies.

A comparison between initial and improved dual microgrippers was also performed. About the top grippers, the increment showed by the improved microgripper in total displacement is of 24.4%, and the temperature distribution only showed a little reduction (7%). For the case of the down gripper, the total displacement decrease in approximately 50%, force remains without change and its temperature shows a little decrement (7.2%).

In both dual microgrippers, the biggest temperature value resides in the chevron inside, at the top part of its shuttle, with 162.76°C. Supply voltage was considered from 0 to 7 V. This swept could be useful to determine the more appropriate voltage level to obtain a desirable response. In each analyzed device, their corresponding modal shapes, using FEA, were determined. The modal shapes analysis allow to understand the performance of the analyzed devices, at the correspondent frequency. From the comparison between initial and improved dual microgrippers, implemented with Silicon, special attention was given to the top grippers. Total displacement showed by the improved microgripper has a maximum value of 0.86 µm. Third natural frequency remains almost without change (4.7%), increasing at 70.38 kHz and the temperature distribution only showed a little reduction (7%, maximum temperature was of 131.49°C), which is better for practical applications. For the case of the down grippers of improved dual microgripper, the total displacement decrease in approximately 50% (with a value of 0.18 µm), force remains without change (3.8 µN) and its temperature decreases (7.2%), at 162.77°C, which is also better for practical applications. These parameters values of the improved dual microgripper are illustrative for possible applications.

Superluminal Hydrogen Atom in a Constant Magnetic Field in (3+1)-dimensional Spacetime (I)

Emmanuel D. K. Gazoya — 2019-06-20

In this paper, we have checked Stern-Gerlach experiment with the aim to study generic effect of an applied magnetic ﬁeld onto transversely directed beam of hydrogen-like atoms. The ultrarelativistic phenomenon of spin of a Dirac particle (especially, electron spin) producing a continuum of linear angular momentum with the known result of superluminal propagation, suggests the feasibility of similar dynamics for a charged hydrogen-like particle under applied magnetic ﬁeld, in spacetime. Another mechanism, very important but popularly less comprehensible, which sustains this linear momentum is known to be helical plane wave expansion. Hydrogen-like spherical waves cannot perform this function due to the perturbation caused by the successive random orientations of their atomic magnetic moment. It is therefore of vital import to investigate experimentally, as well as analytically, the possibility of transformation from hydrogen-like spherical wave expansion to its probable plane wave function, if we would extend our special subatomic theory of superluminal particles to the atomic (hydrogen-like) level.

Physicochemical Characterization and the Effect of Flow-Distance on Correlation between Chemical and Biochemical Oxygen Demands of Industrial Wastewaters

O. M. Myina — 2019-06-20

This work was carried out to establish the effects of the activities of a cluster of industries in Jos-South Local Government Area of Plateau State, Nigeria, on the environmental quality of the industrial area. Some physicochemical parameters – temperature, pH, turbidity, suspended solids (SS), total solids (TS), total hardness, alkalinity, biological oxygen demand (BOD), chemical oxygen demand (COD), heavy metals (Cu 2+ , Co 2+ , Fe 2+ & Zn 2+ ), phosphates, nitrates, sulphates and chlorides – of the wastewaters from the various industries were investigated using standard protocols. Also, the influence of flow-distance on the empirical correlation between biochemical oxygen demand (BOD) and chemical oxygen demand (COD) of the wastewaters was investigated. Wastewater samples were collected at point-sources and at 25, 50, 75 and 100 m distances from the point-sources. Sampling was done twice a week for a full seasonal cycle at peak production period (morning and evening). The samples’ pH was adjusted to 7 using 0.5 M acid for basic samples and 1.0 M alkali for acidic samples, de-chlorinated using 0.0125 M Na 2 S 2 O and seeded when necessary and then diluted with de-ionized water. The ranges of the parameters were as follows: temperature: 22 – 32°C, pH: 5.5 – 10.4, SS: 0 – 1,300 mg/L, TS: 200 – 1.400 mg/L, sulphate: 0.37 – 1.37 mg/L, nitrites: 0.10 – 1.09 mg/L and phosphate: 14.80 – 21.83 mg/L. The phosphate values, especially, were in excess of the maximum contamination limit specified by Federal Environmental Protection Agency (FEPA) and World Health Organization (WHO); and are capable of triggering eutrophication, which will in turn increase BOD/COD values. Concentrations of heavy metals, determined by Atomic Absorption Spectrophotometry (AAS), ranged as follows: 0.07 – 2.01 mg/L for Cu 3 2+ , 0.58 – 3.27 mg/L for Fe , 0.01 – 3.18 mg/L for Zn 2+ and 0.11 – 0.18 mg/L for Co 2+ whose specified standard is not available. BOD values ranged between 5.34 – 25.88 mg/L while COD values ranged from 727.30 –8,308.66 mg/L. Some BOD 5 values were in excess of the allowable limit while all COD values were observed to be very high. This implies an appreciable level of pollution exists here and recipient water bodies of these wastewaters are at risk of being polluted. COD and BOD 5 of the wastewaters from different sources highly correlated with correlation coefficients ranging 0.9396-0.9985. The empirical correlation between COD and BOD 5 5 was generally maintained despite the distance of flow of the wastewater from point-source and contributions of washings from farmlands and other human activities i.e. the correlation between COD and BOD for wastewaters was not affected by flow distance. The correlation equations for the industries may, therefore, be used to deduce rapid effluent quality from chemical oxygen demand (COD) of sample from any point along the effluent flow path.

Characteristics of Spinning Black Holes

Dipo Mahto — 2019-06-20

Aims: The present paper derives an expression for the frequency or wavelength of Hawking radiation emitted by spinning black holes in terms of the event horizon , when the quantum theory of radiation , energy of Hawking radiation and event horizon of the spinning black holes are used. This frequency or wavelength of Hawking radiation may be regarded as the characteristics of spinning black holes and this work is s / 2 extended to derive an expression for the change in the frequency of Hawking radiation with respect to radius of event horizon .
Study Design: The secondary data for the frequencies and wavelengths of Hawking radiation has been calculated from the primary data of rest masses for stellar – mass black holes in XRBs and in AGN resulting the wavelength & and frequency . Our result corresponds to the result of research work entitled: Frequency of Hawking radiation from black holes by Mahto et al. published in International Journal of Astrophysics and Space Science (2013).
Place and Duration of Study: This work has been completed in the department of Physics of Marwari College under T.M.B.U. Bhagalpur from Jan 2016 to Aug 2016.
Methodology: This research work is completely theoretical and the total work has been doneusing Laptop at Marwari College Bhagalpur and University Department of Physics, T.M.B.U. Bhagalpur.

Conclusion: The frequencies/wavelengths of Hawking radiation either emitted from spinning black holes or nonspinning black holes are the same and only depends on their mass. This may be also regarded as the characteristics of spinning black holes in addition to the mass, spin and charge. The mass of black holes are mainly responsible for their identification and characterization and independent from spinning character.

A Comparison of Map-Based Methods for Handling Type-2 and Type-3 Problems of Digital Circuit Design

Ali Muhammad Ali Rushdi — 2019-06-20

With the advent of digital computers, several prominent problems of digital circuit design emerged. A particular elementary class of these problems, (called Type-2 problems) can be divided into two subclasses depending on whether an honest translator is possible or a sneaky translator is warranted. The case of an honest translator is simply an inverse problem of logic, in which knowledge of the vectorial function Z(X) is utilised to produce its inverse vectorial function X(Z). Though an old method of solving type-2 problems was known almost half a century ago, two modern map-based methods are now possible, namely the method of Boolean-equation solving and the method of input-domain constraining. The paper aims to expose and illustrate these two novel methods, with stress on comparing them together and demonstrating their superiority to (as well as an agreement with) the old conventional method. This purpose is achieved by way of three typical classical examples for which conventional solutions are somewhat tedious and cumbersome, while modern solutions are simple and insightful. Throughout these examples, the Karnaugh map is effectively utilised, either in its conventional version or in its variable-entered version. The Boolean-equation-solving method seems to involve certain unwarranted steps that might be possibly skipped. However, its map-based variant is an effective method for handling a related class of digital-design problems called Type-3 problems. An example of a Type-3 problem is given to show how this method resolves and circumvents a certain discrepancy that conventional techniques fell short of handling completely. The present study exposed, illustrated, and compared the two methods of Boolean-equation solving and input-domain constraining, which are novel methods for handling Type-2 problems of digital circuit design. Three typical classical examples are presented, for which known conventional methods of solution are somewhat tedious and cumbersome, while the map-based methods of solution presented herein are simple and insightful. Throughout these examples, the Karnaugh map is effectively utilised, either in its conventional version or in its variable-entered version. When used with Type-2 problems, the Boolean-equation-solving method seems to involve certain unwarranted steps that might be possibly skipped. However, its map-based variant is an effective method for handling a related class of digitaldesign problems called Type-3 problems. An example of a Type-3 problem is given to show how this method resolves and circumvents a certain discrepancy that conventional techniques fell short of handling completely.

Adsorptive Sequestration of Nitrophenol from Phenol Mixture onto Locust Bean Tree Sawdust

Abdur-Rahim Adebisi Giwa — 2019-06-20

The efficacy of an adsorbent prepared from sawdust of Locust bean tree to remove 4-Nitrophenol (4NP), from its aqueous solution and from binary and ternary mixture of phenols (with phenol or / and chlorophenol) was studied. Batch adsorption procedures were carried out to investigate the kinetics, isotherms and thermodynamics of the adsorptive removal, as well as the influence of sawdust dosage, pH, initial concentration of the phenols and temperature on the efficiency of the process. Equilibrium was attained at 12 hours, with the optimum sawdust concentration of 5 g/L. The kinetics of the adsorption could best be described by pseudo-second order model, while Freundlich isotherm gave the best fit in all the systems studied. The adsorption process was thermodynamically nonspontaneous at low temperatures as ∆G was positive; but it was endothermic in the single, binary and ternary systems.

Electrochemical, Spectrochemical and Quantum Chemical Studies on Dimedone as Corrosion Inhibitor for Copper in Acetonitrile

Pipat Chooto — 2019-06-20

A number of techniques have been applied in the investigation of inhibition abilities of dimedone (DMD) for copper in acetonitrile at 25°C. By potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), the corrosion resistance was found to be increased with inhibitor concentration up to 93.68% inhibition efficiency at 3.00 mM, indicating that DMD molecules can cumulatively adsorb on the copper surface and finally form a protective film on copper-solution interface. This is also supported by the decreasing of copper oxidation in cyclic voltammogram. Polarization curves revealed that DMD is of mixed type inhibitor.

The adsorption of DMD on copper surface obeys the Langmuir isotherm and the adsorption mechanism is of physisorption type. The values of standard energy of adsorption (∆G^o_ads) were found to be in good agreement for both polarization and impedance techniques to be -8.17 and -8.43 kJmol^-1 respectively. Fourier Transform Infrared spectroscopy (FT-IR) confirmed the interaction of copper with oxygen on DMD. The mole ratio method suggested that the complexation ratio of copper-DMD is 1:2. Scanning electron microscopy (SEM) of copper surface after immersion in DMD solution indicates the presence of a protective layer on the electrode surface. The frontier molecular orbital energy E_HOMO (highest occupied molecular orbital), E_LUMO (lowest unoccupied molecular orbital) and the Mulliken charge distribution obtained from Quantum chemical calculations revealed (∆E) for DMD 0.2091 hartree, reflecting strong adsorption of the molecules on copper surface. The enhanced corrosion inhibition is possibly due to the compact film structure blocking electron transfer at the electrode surface. This provides a typical example in understanding the system as well as interpretation of the data by both traditional and advanced technology to support the newly coming technology which would make science much more fruitful.

Analytical-numerical Methods Researches of Chaotic Systems

Ismailov Bahram Israfil — 2019-06-20

In this article the theoretical substantiation on the developed mathematical model of the analysis of transient processes of interacting heterogeneous hyperchaotic systems of fractional order is given.

The model represents a thermodynamically spectrum of the dimensions of Poincare’s return time. The thermodynamic category in open system is the entropy of Tsallis in fractional space.

Nanostructure Thin Films Prepared by Using PLD and SILAR Method

Ho Soon Min — 2019-06-20

There are several types of binary, ternary and quaternary thin films have been prepared using pulsed laser deposition (PLD) and successive ion layer adsorption and reaction (SILAR) method. These methods have many advantages such as able to control the dimensions, the growth rate, film thickness and produce nano-particles. In this work, PLD and SILAR methods were briefly discussed. Experimental results for the films prepared using these two deposition techniques from literature review will be described. Characterization of thin films using various tools (SEM, EDAX, XRD, XPS, FTIR, UV-Visible spectrophotometer, Raman Spectra) showed these deposition techniques were suitable to prepare metal chalcogenide thin films.