Development of flat sheet ultrafiltration membrane for heavy metals removal from automobile industrial wastewater / Taha Ali A. Ben Mussa

This thesis is concerned with the production of new flat sheet ultrafiltration (FSUF) membrane. This process includes formulation, fabrication, and characterization of the developed FSUF. Spiral wound module was used in the membrane system for automobile wastewater treatment. About 6,700 lit/vehicle is the average rate of wastewater generation of the automobile industry. In Malaysia, the current treatment process of the automobile industry is activated sludge process (ASP) which shows poor efficiency for heavy metal, COD and BOD5 removal and also, ASP requires high electricity consumption that increases the treatment cost. The objectives of this study are to create a new formula for FSUF membrane to minimize the concentration of heavy metals, COD and BOD5 to the allowable limits. The research work was divided into five phases which include wastewater sampling, membrane development, membrane characterization, module fabrication and wastewater treatment system fabrication. The first phase deals with the characterization of the automobile effluent such as Iron, Chromium, Zinc, Copper and Lead as well as pH, COD, and BOD5. The initial Proton effluent showed that pH and Zn comply with EQA 2009 standards A and B. In addition, COD, BOD5, Fe, Cr and SS do not comply with EQA 2009 standards A and B. Pb and Cu comply with EQA 2009 standard B but not with standard A.The second phase deals with the development, design and fabrication of flat sheet ultrafiltration membrane, 18 membranes formulas were created in stages I & II using titration and % composition processes. From stages I and II, 4 membrane formulas (M1- M4) and 14 membranes (M5- M18) were obtained respectively. In stage II, polymer (PSF) and additive (PVP) concentration are varied in 14 membranes (M5 - M18) and the concentration of the solvent (DMAc) is constant. The third phase is membrane characterization of 18 membranes to get the best performance from stages I and II. Based on flux rate, salt rejection, Spectrophotometer Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and molecular weight cut off (MWCO), one of the developed FSUF membranes was selected to be incorporated into the membrane treatment system. It shows increasing the polymer concentration in the solution causes increasing the thickness of skin and decrease the porosity of the membrane surface. The characterization showed that membranes M2 and M8 are the best membrane performance in stages I and II respectively. The flux rate of for membranes M2 and M8 are 52235 l/m2.hr and 66957 l/m2.hr respectively and that is why membrane M8 was selected to be run in the membrane system. In the fourth phase, there are four types of samples which are raw sample, raw sample after aeration process, raw sample after coagulation process and raw sample after aeration and coagulation processes in series. The last phase is to assess the efficiency of the developed FSUF membrane system. The best system performance in term of heavy metals removal is a system (C) which contains screening, the coagulation process and the developed FSUF membrane. The results of pH, BOD5, COD, (Fe), (Cr), (Zn), (Pb), (Cu), SS and Turbidity after using the membrane system (C) are 6.28, 14.3 mg/l, 24 mg/l, 0.037 mg/l, 0.036 mg/l, 0.08 mg/l, 0.071 mg/l, 0.065 mg/l, 49 mg/l and 16.6 NTU respectively. In conclusion, after using membrane system (C) in the treatment unit in Proton factory, the effluent can be discharged based on EQA 2009 standards A and B

Impact of crosstalk into high resistivity silicon substrate on the RF performance of SOI MOSFET

Crosstalk propagation through silicon substrate is a serious limiting factor on the performance of the RF devices and circuits. In this work, substrate crosstalk into high resistivity silicon substrate is experimentally analyzed and the impact on the RF behavior of silicon-on-insulator (SOI) MOS transistors is discussed. The injection of a 10 V peak-to-peak single tone noise signal at a frequency of 3 MHz ( fnoise) generates two sideband tones of *−56 dBm separated by fnoise from the RF output signal of a partially depleted SOI MOSFET at 1 GHz and 4.1 dBm. The efficiency of the introduction of a trap-rich polysilicon layer located underneath the buried oxide (BOX) of the high resistivity (HR) SOI wafer in the reduction of the sideband noise tones is demonstrated. An equivalent circuit to model and analyze the generation of these sideband noise tones is proposed

Parametrization of the Relativistic (σ−ω\sigma-\omega) Model for Nuclear Matter

We have investigated the zero-temperature equation of state (EoS) for infinite nuclear matter within the $(\sigma-\omega)$ model at all densities $n_{\mathrm{B}}$ and different proton-neutron asymmetry $\eta\equiv(N-Z)/A$. We have presented an analytical expression for the compression modulus and found that nuclear matter ceases to saturate at $\eta$ slightly larger than $0.8$. Afterward, we have developed an analytical method to determine the strong coupling constants from the EoS for isospin symmetric nuclear matter, which allow us to reproduce all the saturation properties with high accuracy. For various values of the nucleon effective mass and the compression modulus, we have found that the quartic self-coupling constant $G_4$ is negative, or positive and very large. Furthermore, we have demonstrated that it is possible (a) to investigate the EoS in terms of $n_{\mathrm{B}}$ and $\eta$; and (b) to reproduce all the known saturation properties without $G_4$. We have thus concluded that the latter is not necessary in the $(\sigma-\omega)$ model.Comment: 15pp; article published online: August 06, 2010 by Phys. Rev.

False synergy between vancomycin and β-lactams against glycopeptide-intermediate Staphylococcus aureus (GISA) caused by inappropriate testing methods

ABSTRACTThe combination of vancomycin and β-lactams is often considered synergistic and has been recommended for the treatment of glycopeptide-intermediate Staphylococcus aureus (GISA) infections. In this study, the combination of vancomycin or teicoplanin with different β-lactams was tested. When using NaCl 4% w/v, for better expression of heterogeneous resistance to β-lactams, with a longer (48-h) incubation period and a higher (107 CFU/mL) inoculum, the association of vancomycin with β-lactams was antagonistic. However, a synergistic effect was observed for teicoplanin under the same conditions

On the Numerical Solution Of Schrodinger Equation

In the beginning, we start with reviewing basic concepts such as inner product and Hilbert spaces ; then we introduce Schrodinger Equation focusing on the solution of time–dependent and time–independent  with a stress on the harmonic oscillator  problem which will be the ingredient for our subject ; namely, the numerical solution of . The numerical solution of is then tackledusing the so–called potential morphing method .Calculations were carried  out for the ground state of the  which represents the frame of reference to work with. The obtained results were compared with similar ones and found to be in very good agreement. Finally, a brief discussion related to possible future work is given ; moreover recent  works on the subject are exposed t

International Lattice Data Grid

We propose the co-ordination of lattice QCD grid developments in different countries to allow transparent exchange of gauge configurations in future, should participants wish to do so. We describe briefly UKQCD's XML schema for labelling and cataloguing the data. A meeting to further develop these ideas will be held in Edinburgh on 19/20 December 2002, and will be available over AccessGrid.Comment: Lattice2002(plenary

Development Of Eco-friendly Chitosan-g-polyacrylamide Preformed Particle Gel For Conformance Control In High-temperature And High-salinity Reservoirs

Oil and gas extraction has become challenging nowadays due to the accompanying amount of excess produced water that results in poor recoverability of hydrocarbon, besides other environmental and economic isues. A recent and efficient technology for conformance control is the injection of preformed particle gels (PPGs), which results in a more practical production process. Nevertheless, existing treatments fail in high-temperature reservoirs, are extremely sensitive to salinity, and are hazardous. The characteristics of the designed PPG, such as mechanical strength and thermal durability, is mainly depend on their crosslinking method. Polysaccharides-based gels prepared by physical crosslinking are weaker than the ones crosslinked by strong covalent bonding. This paper uses one of the polysaccharides and proposes an environmentally friendly PPG for water shutoff applications in reservoirs of high temperature (≤130 °C) and high salinity (200,000 ppm), named chitosan grafted polyacrylamide crosslinked with N, N′-methylene bisacrylamide, synthesized chemically by microwave assisted method. The PPG\u27s chemical compositions, grafting and crosslinking mechanism have been investigated by FTIR spectroscopy and SEM techniques. Swelling kinetics, swelling capacity, and mechanical strength measurements were conducted in different conditions to evaluate the influence of the reservoir conditions, such as salinity, temperature, and pH, on the PPG stability. TGA experiments were also performed to examine the thermal stability. Results have shown that the grafting method has produced a PPG with improved mechanical strength, thermal durability, and salt insensitivity. These results are consistent with the testing observations, where the swelling capacities and the storage modulusof Cs/PAMBA samples, with different MBA content, in deionized water were 2.72–11.64 g/g and 4272.1–22,687 Pa, respectively, while they are 2.52–13.82 g/g and 3699.6–22,910, respectively, in saline solution of TDS 67.2976 g/L. The PPGs are thermally stable and resist temperatures up to 130 °C. Besides being eco-friendly, the Cs/PAMBA showed good long-term thermal stability in high-temperature and high-salinity environments

Impact Of Composition And Salinity On Swelling And Gel Strength Of Poly (acrylamide-co-acrylic Acid) Preformed Particle Gel

The effects of various material compositions and reservoir environments on the ultimate strength and swelling kinetics of a commercial preformed particle gel (PPG) have been investigated. This study used different ratios of acrylamide and acrylic acid copolymers with a specific crosslinker concentration. Results have indicated that increasing the acrylic acid proportion enhances the PPGs\u27 ability to swell but weakens their network structure. In contrast, increasing the crosslinker content decreases the swelling ratio and increases the gel strength. The highest equilibrium swelling capacity among the six preformed particle gel samples was obtained for PPG2, which has the highest acrylic acid amount and the lowest crosslinker content, with a swelling ratio of 2400 g/g in deionized water and 59.8 g/g in brine 1 (67535.8 mg/l). On the contrary, PPG5, with the lowest acrylic acid and highest crosslinker content, has a swelling capacity of 239 g/g and more than 17 g/g in distilled and brine 1, respectively. Yet, PPG5 has the highest swollen gel strength of 615.5 Pa in deionized water and 3344 Pa in brine 1. The PPGs\u27 swelling ratios showed stepwise improvements along with increasing temperature, notably after 50 °C, yet the storage modulus (G′) was negatively affected. The PPGs revealed the highest swelling behavior in pH 6–8, decreasing dramatically in more acidic and basic conditions. The swelling ratios of the PPGs in brine 1 at 50 °C were between 12 and 32 g/g, having strengths in the range of 566–5508 Pa, depending on the crosslinker ratio. The PPGs also demonstrated the ability to compete with other commercial PPGs as they have shown physical and thermal stability when aging at 50 °C, specifically those with high crosslinker content (PPG5)

Synthesis by the polyol process and ionic conductivity of nanostructured La2Mo2O9 powders

International audienceLa2Mo2O9 nanostructured powders were synthesized by the polyol process. The effects of the nature of the polyol, the refluxing time, the hydrolysis ratio, the metal concentration and the addition of hydroxide ions, on the purity and morphology of the powders are determined. Two main morphologies are observed, the particles being in the shape of platelets or spheres, with respectively diethylene glycol or ethylene glycol as solvent. A specific surface area of 24 m2/g was reached by varying the metal concentration. The conductivity measurements were recorded on pellets that present in some cases a closed porosity, the relative density reaching 95% without any milling step. According to the synthesis parameters, the grain conductivity can be slightly increased, the total conductivity remaining only slightly lower than that of pellets made of powders synthesized by solid state reaction

An Agent-based Simulator for the Gastrointestinal Pathway of Listeria monocytogenes

We developed an agent-based gastric simulator for a human host to illustrate the within host survival mechanisms of Listeria monocytogenes. The simulator incorporates the gastric physiology and digestion processes that are critical for pathogen survival in the stomach. Mathematical formulations for the pH dynamics, stomach emptying time, and survival probability in the presence of gastric acid are integrated in the simulator to evaluate the portion of ingested bacteria that survives in the stomach and reaches the small intestine. The parameters are estimated using in vitro data relevant to the human stomach and L. monocytogenes. The simulator predicts that 5%–29% of ingested bacteria can survive a human stomach and reach the small intestine. In the absence of extensive scientific experiments, which are not feasible on the grounds of ethical and safety concerns, this simulator may provide a supplementary tool to evaluate pathogen survival and subsequent infection, especially with regards to the ingestion of small doses