Money Multiplier As a Determinant of Money Supply: The Case of Pakistan

Monetary policy is an important instrument for pursuing growth and stability in a less developed economy. However, it can yield desired results if and only if it is judiciously formulated and properly implemented. An appropriate formulation of monetary policy requires two basic relations to hold: (1) the demand function for money must be reasonably stable and empiri¬cally available to the monetary authorities and (2) the stock of money must be subject to control by the monetary authorities and the mechanism through which money supply is quantitatively determined in an economy should be clear to the policy-makers

Foreign Trade Regimes and Economic Development: Egypt. By Bent Hansen and Karim Nashashibi. New York: Columbia University Press. 1975. XXXV +358 pp.(Published by the National Bureau of Economic Research, New York).

The book under review is one of a series of studies conducted under the auspices of the National Bureau of Economic Research. The primary object was the empirical exploration of a classical doctrine that trade is an engine of growth. The book consists of three major parts. In part one analysis of the Egyptian trade regimes at an aggregate level, from World War II to the Sixties, is presented in five chapters. Chapter 1 outlines Egypt's foreign trade, economic development and political characteristics in a historical perspective. After discussing ninety years of free trade it moves on to explain how Egypt's industrial sector expanded through protection and the increased demand resulting from the outbreak of World War II. Thereafter, during the Nasser regime the economy underwent a metamorphosis, namely, nationalization of all industries, finance and trade. Consequently, by the end of the Sixties the public sector's share in gross dome¬stic product and investment was as high as 50 percent and 90 perecent. respectively

Excess conductivity of Cu₀.₅Tl₀.₅Ba₂Ca₃Cu₄₋yZnyO₁₂₋δ superconductors

Oxide high-Tc superconductors (HTSC) are anisotropic in character since the charge carriers have free moment in the conducting CuO₂ planes [1] whereas their motion is impeded by insulating/partially insulating MBa₂O₄₋δ (M = Y, Bi, Hg, Tl, CuTl, etc.) charge reservoir layers. In the transport process the charge carriers have to tunnel across insulating/partially insulating barriers along the c-axis and across the grain boundaries, which promote a fluctuation in the order parameter and in turn to the conductivity of the carriers. The studies of such fluctuation conductivity (FIC) may help in understanding the intrinsic mechanism of superconductivity. Here the electrical resistivity ρ(T) versus temperature data of as-prepared and oxygen post-annealed Cu₀.₅Tl₀.₅Ba₂Ca₃Cu₄₋yZnyO₁₂₋δ (y = 0, 0.5, 1.5, 2.5) samples is studied for FIC analyses in the temperature regime well above the critical temperature; such analyses have been carried out by employing Lawrence and Doniach (LD) and Maki–Thompson (MT) models. The coherence length, inter-plane coupling, exponent, dimensionality of fluctuations and the phase relaxation time of the carriers are determined from such analyses. It is observed that the crossover temperature associated with two distinct exponents fits very well with the two-dimensional (2D) and three-dimensional (3D) LD equations. The crossover temperature T0 is shifted to higher temperatures with enhanced Zn doping. The 3D LD region is shifted to higher temperature with the increased Zn doping. We have elucidated from these analyses that lower Tl content in the final compound may increase the charge carrier’s doping efficiency of MBa2O4–δ charge reservoir layer, resulting into an increase in the coherence length along the c-axis and superconductivity parameters. A small decrease in the coherence length along the c-axis ξc(0) is observed in the samples with Zn doping of y = 1.5 whereas ξc(0) increases in the samples y = 0.5, 2.5. In comparison with as-prepared samples, the ξc(0) decreases after post-annealing in oxygen atmosphere. It is most likely that a decrease in the density of charge carrier’s is promoted by oxygen diffusion in the unit cell may suppress the ξc(0). The increase oxygen diffusion is evidenced from the softening of phonon modes after postannealing in oxygen atmosphere. The decreased population of small spins of Cu atoms induced by doping of Zn is viewed in the terms of suppression of spin gap and hence the pseudo-gap in Cu₀.₅Tl₀.₅Ba₂Ca₃Cu₄₋yZnyO₁₂₋δ (y = 0, 0.5, 1.5, 2.5) samples

Performance enhancement and emissions mitigation of DI-CI engine fuelled with ternary blends of jatropha biodiesel-diesel-heptanol

The rising consumption of fossil fuels has lead to massive depletion of the petroleum reserves. The combustion of diesel has contributed to serious environmental problems which prove to be detrimental for human life and biodiversity. In order to meet the challenges of energy security and pollution control, researchers have come with ternary blends comprising of jatropha biodiesel-diesel-alcohol blend in different volumetric proportions. Ternary blends can serve the dual purpose of alternate and sustainable fuel for the modern transport sector. Besides, they offer huge potential in improving the engine performance and lowering the exhaust emissions. Biodiesel and alcohol are derived from renewable sources of agricultural feed stocks. The physical–chemical properties of both biodiesel and alcohol are similar to those of conventional diesel. Many studies have reflected that higher alcohols prove to be better additives than lower alcohols in biodiesel. The present work deals with the analysis of performance and emissions of diesel engine fueled with ternary blends. The preparation of four test fuel samples (ternary blends) were done, namely DBHep10 (D = 40%, B = 50%, Heptanol = 10%), DBHep20 (D = 40%, B = 40%, Heptanol = 20%), DBHep30 (D = 40%, B = 30%, Heptanol = 30%) and DBHep40 (D = 40%, B = 20%, Heptanol = 40%). The test fuels were tested in CRDI diesel engine at varied engine loads of 5 Nm, 10 Nm, 15 Nm and 20 Nm, while the engine speed was kept constant at 1800 rpm. The ternary blends resulted in higher BTE and lower BSFC with increased volumetric proportion of heptanol. The CO and UHC emissions were reduced for ternary blends than diesel, however NOx emission got increased. The use of heptanol up to 40% as additives in biodiesel-diesel blends showed huge potential as alternate and sustainable fuel

Comprehensive analysis of design software application in solar distillation units

The use of solar stills in rural regions are becoming increasingly popular as it is an economical solution for drinking water from saline water sources. Many researchers have worked for the improvement of conventional solar still to enhance productivity. Costly and time-consuming processes of operation in solar stills encourage many scholars to analyze mathematical simulation. This paper presents comprehensive reviews of the application of different design software to solar still systems. Design software is essential for developing and analyzing the mathematical models and predicting the most suitable performance parameters for the enhanced production rate of distilled water for still systems. Numerical modeling of solar still systems is necessary to analyze and investigate air movement, temperature variation for knowing water temperature, and air temperature through software like CFD, MATLAB, FORTRAN, TRYNSYS AutoCAD. The simulation technique's application using CFD is made with TRNSYS, FLUENT, ANSYS, FORTRAN and MATLAB which are useful tools to develop such mathematical models for the prediction of flow parameters. Engineering Equation Solver (EES) package and COMSOL Multiphysics solve the differential energy balance equation. All newly developed software employed for the utility of still solar systems is discussed. This article provides a comprehensive overview of the various software tools used in solar still to help researchers, scientists, and academicians

Parabolic trough solar collectors: A sustainable and efficient energy source

Fossil fuels are a finite resource that is becoming increasingly expensive. Solar energy is a renewable resource that has the potential to provide a lifetime supply of energy. Parabolic trough solar collectors are a type of solar thermal collector that can be used to generate electricity. This paper discusses the potential advantages and challenges of using parabolic trough solar collectors. One of the main advantages of parabolic trough solar collectors is their scalability. They can be used to generate electricity on a small scale, such as for a home or business, or on a large scale, such as for a power plant. Parabolic trough solar collectors are also reliable and have a long lifespan. They are not as susceptible to weather damage as other types of solar collectors, such as photovoltaic panels. However, there are some challenges associated with using parabolic trough solar collectors. One challenge is that they require large land areas. Another challenge is that they can be expensive to maintain. Despite the potential, further research is essential to address these issues. Future prospects lie in optimizing land use, enhancing maintenance strategies, and advancing collector technology to harness the full potential of parabolic trough solar collectors. Overall, parabolic trough solar collectors are a promising technology for generating electricity from solar energy. However, more research is needed to address the challenges associated with this technology

A comparative analysis of friction stir and tungsten inert gas dissimilar AA5082-AA7075 butt welds

The aluminium alloys AA5082 and AA7075 were welded using friction stir welding (FSW) and tungsten inert gas (TIG) welding. The effect of these two (FSW and TIG) welding processes on the tensile and fatigue properties of dissimilar AA5082-AA7075 butt welded joints were studied. The S-N curve for both, FSW and TIG, joints were established. The results exhibited that the tensile and fatigue properties of dissimilar FSW welded butt joints are better than those of dissimilar TIG welded butt joints. The fatigue strength for FSWed and TIG welded joint is determined as 40 MPa for 106 cycles and 30 MPa for 105 cycles of fatigue life, respectively. The micro-hardness of the joints is also studied for both joints. The hardness for TIG joint is lower than the FSWed joint in the welded zone