Sustainable Development and Environmentally Friendly Energy Systems

People are relying upon oil for primary energy and this will continue for a few more decades. Other conventional sources may be more enduring but are not without serious disadvantages. The renewable energy resources are particularly suited for the provision of rural power supplies and a major advantage is that equipment such as flat plate solar driers, wind machines, etc., can be constructed using local resources. Without the advantage results from the feasibility of local maintenance and the general encouragement, such local manufacture gives to the buildup of a small-scale rural-based industry. This communication comprises a comprehensive review of energy sources, the environment, and sustainable development. It includes the renewable energy technologies, energy efficiency systems, energy conservation scenarios, energy savings in greenhouses environment and other mitigation measures necessary to reduce climate change. This study gives some examples of small-scale energy converters, nevertheless, it should be noted that small conventional, i.e., engines are currently the major source of power in rural areas and will continue to be so for a long time to come

Promotion and Implementation of Bioenergy for a Better Environment

- There is strong scientific evidence that the average temperature of the earth's surface is rising and this may be attribute to increased concentration of carbon dioxide (CO2), and other greenhouse gases (GHGs) in the atmosphere as released by burning fossil fuels. One of the chief sources of greenhouse gases is burning of fossil fuels. Biogas from biomass appears to have potential as an alternative energy source, which is potentially rich in biomass resources. In the present paper, current literature is reviewed regarding the ecological, social, cultural and economic impacts of biogas technology. In this article an attempt has been made to give an overview of present and future use of biomass as an industrial feedstock for production of fuels, chemicals and other materials. However, to be truly competitive in an open market situation, higher value products are required

Performance, Modeling, Measurements, and Simulation of Energy Efficient for Heat Exchanger, Refrigeration and Air Conditioning

Over the years, all parts of a commercial refrigerator, such as the compressor, heat exchangers, refrigerant, and packaging, have been improved considerably due to the extensive research and development efforts carried out by academia and industry. However, the achieved and anticipated improvement in conventional refrigeration technology are incremental since this technology is already nearing its fundamentals limit of energy efficiency is described is ‘magnetic refrigeration\u27 which is an evolving cooling technology. The word ‘green\u27 designates more than a color. It is a way of life, one that is becoming more and more common throughout the world. An interesting topic on ‘sustainable technologies for a greener world\u27 details about what each technology is and how it achieves green goals. Recently, conventional chillers using absorption technology consume energy for hot water generator but absorption chillers carry no energy saving. With the aim of providing a single point solution for this dual-purpose application, a product is launched but can provide simultaneous chilling and heating using its vapor absorption technology with 40% saving in heating energy. Using energy efficiency and managing customer energy use has become an integral and valuable exercise. The reason for this is green technology helps to sustain life on earth. This not only applies to humans but to plants, animals and the rest of the ecosystem. Energy prices and consumption will always be on an upward trajectory. In fact, energy costs have steadily risen over last decade and are expected to carry on doing so as consumption grows

Epicyclic oscillations of fluid bodies Paper II. Strong gravity

Fluids in external gravity may oscillate with frequencies characteristic of the epicyclic motions of test particles. We explicitly demonstrate that global oscillations of a slender, perfect fluid torus around a Kerr black hole admit incompressible vertical and radial epicyclic modes. Our results may be directly relevant to one of the most puzzling astrophysical phenomena -- high (hundreds of hertz) frequency quasiperiodic oscillations (QPOs) detected in X-ray fluxes from several black hole sources. Such QPOs are pairs of stable frequencies in the 3/2 ratio. It seems that they originate a few gravitational radii away from the black hole and thus observations of them have the potential to become an accurate probe of super-strong gravity.Comment: submitted to Classical and Quantum Gravit

Quasi-Periodic Oscillations from Magnetorotational Turbulence

Quasi-periodic oscillations (QPOs) in the X-ray lightcurves of accreting neutron star and black hole binaries have been widely interpreted as being due to standing wave modes in accretion disks. These disks are thought to be highly turbulent due to the magnetorotational instability (MRI). We study wave excitation by MRI turbulence in the shearing box geometry. We demonstrate that axisymmetric sound waves and radial epicyclic motions driven by MRI turbulence give rise to narrow, distinct peaks in the temporal power spectrum. Inertial waves, on the other hand, do not give rise to distinct peaks which rise significantly above the continuum noise spectrum set by MRI turbulence, even when the fluid motions are projected onto the eigenfunctions of the modes. This is a serious problem for QPO models based on inertial waves.Comment: 4 pages, 2 figures. submitted to ap

Effect of some tillage methods and sowing dates on bulk density, soil moisture and sorghum yield in the rainfed areas of northern Gedarif , Gedarif State , Sudan

     The study was carried out during three consecutive seasons (2005/06, 2006/07 and 2007/08) under rain-fed conditions, to investigate the effect of some tillage methods and sowing dates  of  sorghum (Sorghum bicolor L.) on soil moisture  content, bulk density and sorghum grain  yield  in  northern Gedarif area, at the pilot farm of the Faculty of Agricultural  and Environmental Sciences, University of  Gedarif, Gedarif, Sudan. The experiment was laid out in a split plot design with three replicates. Main plots were assigned to three tillage methods; which were:  Zero tillage (ZT), offset disc as post harvest tillage(PHT) and farmers practice which was  wide level disc (WLD) as control, while sub-plots were assigned  to two sowing dates  which were early sowing date (S1) and late sowing date (S2). Post-harvest tillage treatment (PHT) resulted in significantly higher soil moisture content in the three growing seasons  compared to the other two treatments. Combined analysis indicated that ZT resulted in  significantly higher soil bulk density  in comparison with WLD and PHT treatments  for the three depths. The 3-years average grain yield for PHT, WLD and ZT were 1113 kg/ha, 976 kg/ha and 885 kg/ha, respectively.  The respective increase in yield was  26% and 14%.                                                                                                                                                                              The study was carried out during three consecutive seasons (2005/06, 2006/07 and 2007/08) under rain-fed conditions, to investigate the effect of some tillage methods and sowing dates  of  sorghum (Sorghum bicolor L.) on soil moisture  content, bulk density and sorghum grain  yield  in  northern Gedarif area, at the pilot farm of the Faculty of Agricultural  and Environmental Sciences, University of  Gedarif, Gedarif, Sudan. The experiment was laid out in a split plot design with three replicates. Main plots were assigned to three tillage methods; which were:  Zero tillage (ZT), offset disc as post harvest tillage(PHT) and farmers practice which was  wide level disc (WLD) as control, while sub-plots were assigned  to two sowing dates  which were early sowing date (S1) and late sowing date (S2). Post-harvest tillage treatment (PHT) resulted in significantly higher soil moisture content in the three growing seasons  compared to the other two treatments. Combined analysis indicated that ZT resulted in  significantly higher soil bulk density  in comparison with WLD and PHT treatments  for the three depths. The 3-years average grain yield for PHT, WLD and ZT were 1113 kg/ha, 976 kg/ha and 885 kg/ha, respectively.  The respective increase in yield was  26% and 14%.                                                                                                                                                                       &nbsp

The Kozai Mechanism and the Evolution of Binary Supermassive Black Holes

We consider the dynamical evolution of bound, hierarchical triples of supermassive black holes that might be formed in the nuclei of galaxies undergoing sequential mergers. The tidal force of the outer black hole on the inner binary produces eccentricity oscillations through the Kozai mechanism, and this can substantially reduce the gravitational wave merger time of the inner binary. We numerically calculate the merger time for a wide range of initial conditions and black hole mass ratios, including the effects of octupole interactions in the triple as well as general relativistic periastron precession in the inner binary. The semimajor axes and the mutual inclination of the inner and outer binaries are the most important factors affecting the merger time. We find that for a random distribution of inclination angles and approximately equal mass black holes, it is possible to reduce the merger time of a near circular inner binary by more than a factor of ten in over thirty percent of all cases. We estimate that a typical exterior quadrupole moment from surrounding matter in the galaxy may also be sufficient to excite eccentricity oscillations in supermassive black hole binaries, and also accelerate black hole mergers

Effect of Gum Arabic in Management of Malnourished Children Aged 6 – 59 Months

Background: Malnutrition is globally the most important risk factor for morbidity and mortality, contributing to more than half of deaths in children worldwide. Gum Arabic is indigestible food ingredient with a potential effect as prebiotic and antidiarrheal. Aim of the study: To determine the effect of gum Arabic in management of malnourished children aged 6- 59 months and its effect on edema, diarrhea, and mood changes among them. Method:  This is an interventional, open-label randomized, controlled trial, hospital-based study conducted among 162 malnourished child admitted to Ahmed Gasim Teaching Hospital and Mohammed Elamin Hamid Pediatric Hospital during Jan. – July 2015. Participants were selected randomly, and equally distributed to control group (81 malnourished children) who were managed as guided by the WHO developed protocol for managing malnutrition and study group (81 malnourished children) received gum Arabic in addition to management protocol and the both groups received management for 2 weeks (30 mg/day for children > 1 year and 15 mg/day for children < 1 year). Results: Out of 162 malnourished children, 54.3% had age of 13- 24 months, males were 64.2%. On starting, 72.8% had weight for height <-3SD, 46.3% of them had diarrhea, 35.2% had edema, 65.4 were irritable and 24.1% were apathetic. On 14th day, in study and control groups, mean WFH increased by 9.26% and 7.6% respectively, diarrhea stopped in 97.06% and 78.05% respectively, edema subsided in 96.7% and 57.1% respectively, Also, 98.6% from study group and 73.2% from control group were active and smiling. The variation in the 4 assessed variables was revealed statistically significant (P value < 0.05). Conclusion and recommendation: Gum Arabic found to have positive effect when added to the WHO management protocol for severe acute malnutrition. Wide and well-established use of gum Arabic as Prebiotic will increase its economic values. Keywords: Gum Arabic, Malnourished, Childre

Fungal infections of grapevine roots in phylloxera-infested vineyards

Wounds caused by feeding of grape phylloxera on grape roots can become infected with a variety of fungi. Fusarium roseum, F. oxysporum and Pythium ultimum are important in Vitis vinifera Chardonnay wounds whereas F. oxysporum and Cephalosporium sp. are important for the moderately tolerant rootstock AXR#1. Proportion of root lengths infected in the phloem parenchyma were measured in two vineyards through the 1996 growing season and into the winter. Infection rates were highest in spring (as measured in May) but decreased to a low level by the end of summer. There was a second infection peak in fall. We suggest that the decline in fungal infections was due to death of highly infected roots and their removal from the sampled pool of roots. Loss of roots is a logical cause of vine decline and explains why there have been poor correlations between phylloxera populations and vine damage symptoms