Treatment of Sewage by using Two-Stage Rotating Biological Contactor (RBC)

The rotating biological contactor (RBC) process offers the specific advantages of a bio-film system in treatment of wastewater for removal of soluble organic substance. The present review of RBC focus on parameter like materials used in fabrication of RBC Unit, media used for development of bio-film, HRT, organic and hydraulic loading rate, influent wastewater characteristics, Analysis treated wastewater characteristics, submergence variation, constant RPM, sizing of the reactor. In present study, a lab scale two stage RBC reactor is fabricated to treat sewage. Here work is carried out to check the performance and efficiency of two stage RBC reactor to treat sewage by varying submergence and maintaining constant speed (RPM).From present study, the two stages RBC is varied with 2 submergences for constant speed of disc as 4 RPM with different COD loading rate at optimum HRT. The result obtained when the disk submergence was 40%, the COD removal efficiency for tank1 was 90.31% and for tank1+tank2 were 93.8%. Hence optimum COD loading rate was 640 mg/L at optimum 2hrs HRT and when the disk submergence was 45%, the COD removal efficiency for tank1 was 90.76 % and for tank1+tank2 were 94.6 %. Hence optimum COD loading rate was 520 mg/L at optimum HRT of 1 hr. Keywords: Two stage Rotating Biological contactor (RBC), sewage, Optimum COD Loading Rate and HRT

Generation of Groundwater Quality Index Map: A Case Study

Reliance on groundwater has been rapidly increasing, especially in the arid and semiarid regions, resulting in its overexploitation leading to deterioration of quality. Kurmapalli Vagu basin of Andhra Pradesh, a semi-critical region with respect to the stage of groundwater development is a good example. Its monitoring and assessment is imperative for devising preventive measures against health hazards. Groundwater samples from twenty five locations were collected and analyzed for various physico-chemical parameters in terms of Water Quality Index (WQI) to determine its suitability for drinking purposes. Seven locations were found to have WQI value within the limits. High values of WQI were mostly due to high content of Fluorides. WQI Contour map was generated to study spatial distribution of quality of groundwater. Suitable remedial measures and groundwater augmenting structures are proposed in the study area to improve the quality of groundwater. Keywords: Groundwater, WQI, Fluorosis, Groundwater augmenting structures

Qualitative observation of reversible phase change in astrochemical ethanethiol ices using infrared spectroscopy

Here we report the first evidence for a reversible phase change in an ethanethiol ice prepared under astrochemical conditions. InfraRed (IR) spectroscopy was used to monitor the morphology of the ice using the Ssingle bondH stretching vibration, a characteristic vibration of thiol molecules. The deposited sample was able to switch between amorphous and crystalline phases repeatedly under temperature cycles between 10 K and 130 K with subsequent loss of molecules in every phase change. Such an effect is dependent upon the original thickness of the ice. Further work on quantitative analysis is to be carried out in due course whereas here we are reporting the first results obtained

Coupled Phonons, Magnetic Excitations and Ferroelectricity in AlFeO3: Raman and First-principles Studies

We determine the nature of coupled phonons and magnetic excitations in AlFeO3 using inelastic light scattering from 5 K to 315 K covering a spectral range from 100-2200 cm-1 and complementary first-principles density functional theory-based calculations. A strong spin-phonon coupling and magnetic ordering induced phonon renormalization are evident in (a) anomalous temperature dependence of many modes with frequencies below 850 cm-1, particularly near the magnetic transition temperature Tc ~ 250 K, (b) distinct changes in band positions of high frequency Raman bands between 1100-1800 cm-1, in particular a broad mode near 1250 cm-1 appears only below Tc attributed to the two-magnon Raman scattering. We also observe weak anomalies in the mode frequencies at ~ 100 K, due to a magnetically driven ferroelectric phase transition. Understanding of these experimental observations has been possible on the basis of first-principles calculations of phonons spectrum and their coupling with spins

Radiative Phase Transitions and Casmir Effect Instabilities

Molecular quantum electrodynamics leads to photon frequency shifts and thus to changes in condensed matter free energies often called the Casimir effect. Strong quantum electrodynamic coupling between radiation and molecular motions can lead to an instability beyond which one or more photon oscillators undergo a displacement phase transition. The phase boundary of the transition can be located by a Casimir free energy instability.Comment: ReVTeX4 format 1 *.eps figur

Mind over matter: investigation of materialization of intentions

In this article, we present our investigation of materialization of intentions using the input-output data based Six Sigma methodology for problem solving. The investigation is inspired by our respective Gurus, the wisdom of present and past seers, and the works of several scientists. We present two examples of materialization of intentions (change of pH and levitation). The pH example is preliminary requiring additional experimentation. We believe that the evidence presented is very supportive of the hypothesis of materialization of intentions. We hope this paper will contribute towards the unfolding of a Copernican-like revolution which will have profound positive impact on humanity

Perspectives in Marine Aquatic Resources and Health Management

Aquatic resources are now regarded as major contributors to provisioning services that include health-food supply and pharmaceutical products. There are tremendous opportunities to advantageously make use of the rich biodiversity; and the provisioning, regulatory, cultural and supporting services of our seas to meet the emerging demands of humankind. Since biodiversity and ecosystem functioning is inextricably linked to human societies, we have to value the services of both, considering the growing costs of biodiversity loss and ecosystem degradation. A greener environment with enhanced ecosystem services will be beneficial to the ecological and human well-being

Effect of water-wall interaction potential on the properties of nanoconfined water

Much of the understanding of bulk liquids has progressed through study of the limiting case in which molecules interact via purely repulsive forces, such as a hard-core potential. In the same spirit, we report progress on the understanding of confined water by examining the behavior of water-like molecules interacting with planar walls via purely repulsive forces and compare our results with those obtained for Lennard-Jones (LJ) interactions between the molecules and the walls. Specifically, we perform molecular dynamics simulations of 512 water-like molecules which are confined between two smooth planar walls that are separated by 1.1 nm. At this separation, there are either two or three molecular layers of water, depending on density. We study two different forms of repulsive confinements, when the interaction potential between water-wall is (i) $1/r^9$ and (ii) WCA-like repulsive potential. We find that the thermodynamic, dynamic and structural properties of the liquid in purely repulsive confinements qualitatively match those for a system with a pure LJ attraction to the wall. In previous studies that include attractions, freezing into monolayer or trilayer ice was seen for this wall separation. Using the same separation as these previous studies, we find that the crystal state is not stable with $1/r^9$ repulsive walls but is stable with WCA-like repulsive confinement. However, by carefully adjusting the separation of the plates with $1/r^9$ repulsive interactions so that the effective space available to the molecules is the same as that for LJ confinement, we find that the same crystal phases are stable. This result emphasizes the importance of comparing systems only using the same effective confinement, which may differ from the geometric separation of the confining surfaces.Comment: 20 pages, 10 figure

A micro-convection model for thermal conductivity of nanofluids

Increase in the specific surface area as well as Brownian motion are supposed to be the most significant reasons for the anomalous enhancement in thermal conductivity of nanofluids. This work presents a semi-empirical approach for the same by emphasizing the above two effects through micro-convection. A new way of modeling thermal conductivity of nanofluids has been explored which is found to agree excellently with a wide range of experimental data obtained by the present authors as well as the data published in literature