Improving rheological properties of Gambe clay for drilling fluid application using fermentable polymers

There are abundant bentonitic clay deposits in Nigeria. However, it does not meet commercial standard for drilling mud formulation, because it is composed of calcium montmorillonite. Therefore, there is need for the clay to be enhanced and polymers have been identified as enhancement agents. The work was aimed at improving the rheological properties of Gambe clay for drilling fluid formulation using the fermentable polymers (xanthan gum, locust bean gum and tamarind seed gum). The clay was obtained from Gambe town in Adamawa State, Nigeria. The clay was beneficiated for quartz removal and chemical beneficiated with 6 wt% of Na2CO3. The mineral composition and the cation exchange capacity of the clay was determined using X-ray diffraction analysis and ammonium acetate saturation method, respectively to find out its quality for drilling mud formulation. Drilling mud was formulated by mixing of 22.5 g of the clay to 350 ml of water with a high speed mixer to obtain a homogenous mixture. The polymer enhancers were also added to the mixture. The effect of the fermentable polymer at different concentration on the rheological properties of the formulated drilling fluid was investigated employing FANN 35SA viscometer. It was found that 0.93 wt% of the tamarind seed gum, locust bean gum and xanthan gum in the formulated drilling fluid enhanced the yield point from 0.72 Pa to 7.2 Pa, 12.48 Pa and 16.36 Pa, and the gel strength from 0 Pa to 8.35 Pa, 10.44 Pa and 68.92 Pa of the formulated mud respectively. The mud enhanced with 0.80 wt% of the enhancers had high rheological properties than imported clay.Keywords: Drilling mud, Gambe clay, tamarind seed gum, locust bean gum, rheological propertie

Effect of blending on fuel gas composition of pyrolysed plastic wastes

An investigation into the effects of blending on the gaseous product distribution of plastic wastes was carried out. Waste Low Density Polyethylene (LDPE) and waste High Density Polyethylene (HDPE) samples were subjected to thermal pyrolysis in an electric tubular furnace. First, the effect of heating rate on the volume of the gaseous products was studied. Heating rate values of 22oC/min, 26oC/min and 32oC/min were used with results showing that a higher heating rate favoured the production of non-condensable gases in HDPE but caused a persistent decrease in LDPE. The investigation into the effects of blending was then carried out at a temperature range of 480oC – 600oC and heating rate of 22oC/min using blends of 0%, 20%, 40%, 50%, 60%, 80% and 100% LDPE in HDPE. The gaseous product was analysed by gas chromatography and results obtained showed a similarity in hydrocarbon product distribution for both LDPE and HDPE gas products. 100% LDPE showed a composition of 21.84%, 47.39%, 20.78%, 8.40%, and 1.59%; and 100% HDPE showed a composition of 18.88%, 46.91%, 22.89%, 9.59%, and 1.73% for C1, C2, C3, C4, and C5+ hydrocarbon molecules respectively. The presence of LDPE in blends of LDPE-HDPE favoured the production of C1 up to 99 mol. %.Keywords: pyrolysis, waste plastics, LDPE, HDPE, fuel ga

Detection of Multidrug-Resistant Acinetobacter baumannii among Gram-Negative Bacteria Isolated from Clinical Samples

Acinetobacter baumannii is an aerobic, Gram -negative cocco-bacilli, non-fermentative, non-motile, and non-fastidious organism belonging to the genus Acinetobacter. The A. baumannii has emerged as a worldwide nosocomial pathogen causing about 80%25 of nosocomial infections comprising ventilator-acquired pneumonia, bacteremia, meningitis, urinary tract infections, skin and soft tissues infections associated with high mortality rate of approximately 63.3%25. Although literature shows sufficient information about the drug resistant A. baumannii, there has been inadequate reports on the antibiotic resistance level of this bacterium in the study area. The aim of this research was to detect Multidrug-resistant A. baumannii isolates among Gram-negative bacteria isolated from Federal Teaching Hospital, Gombe, Nigeria. A total of 1008 clinical samples were collected and cultured on MacConkey agar and Blood agar plates at 37o C for 18-24 hours. Following the incubation period, discrete colonies obtained were subjected to Gram staining. The Gram-negative isolates were identified based on conventional biochemical tests with further use of VITEK 2 COMPACT (BioMérieux, France) for confirmation of A. baumannii amongst the Gram-negative organisms. The results obtained showed that 263 Gram-negative organisms were isolated. A. baumannii accounted for 8.5%25 prevalence. Most of the A. baumannii isolated were from the male patients (75%25) within the age range of 33-48 years. Antibiotic susceptibility test using Kirby Bauer method in accordance with CLSI guidelines was done on 20 A. baumannii isolates. The isolates were more sensitive to levofloxacin (60%25), followed by Gentamicin (55%25), then Ciprofloxacin and Tetracycline (50%25) respectively. High level of resistance to Ceftriaxone (80%25), Cefepime (75%25), Ceftazidime (65%25), Piperacillin-Tazobactam (55%25), Ampicillin%252FSulbactam (60%25), Tigecycline (60%25), Meropenem (55%25) and Amikacin (60%25). This study revealed that 15 (75%25) of the A. baumannii were found to be multidrug-resistant. Therefore, antibiotic stewardship is necessary to combat further dissemination of this organism

All-sky search for long-duration gravitational wave transients with initial LIGO

We present the results of a search for long-duration gravitational wave transients in two sets of data collected by the LIGO Hanford and LIGO Livingston detectors between November 5, 2005 and September 30, 2007, and July 7, 2009 and October 20, 2010, with a total observational time of 283.0 days and 132.9 days, respectively. The search targets gravitational wave transients of duration 10-500 s in a frequency band of 40-1000 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. All candidate triggers were consistent with the expected background; as a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. For signals from black hole accretion disk instabilities, we set upper limits on the source rate density between 3.4×10-5 and 9.4×10-4 Mpc-3 yr-1 at 90% confidence. These are the first results from an all-sky search for unmodeled long-duration transient gravitational waves. © 2016 American Physical Society

All-sky search for long-duration gravitational wave transients with initial LIGO

We present the results of a search for long-duration gravitational wave transients in two sets of data collected by the LIGO Hanford and LIGO Livingston detectors between November 5, 2005 and September 30, 2007, and July 7, 2009 and October 20, 2010, with a total observational time of 283.0 days and 132.9 days, respectively. The search targets gravitational wave transients of duration 10-500 s in a frequency band of 40-1000 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. All candidate triggers were consistent with the expected background; as a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. For signals from black hole accretion disk instabilities, we set upper limits on the source rate density between 3.4×10-5 and 9.4×10-4 Mpc-3 yr-1 at 90% confidence. These are the first results from an all-sky search for unmodeled long-duration transient gravitational waves. © 2016 American Physical Society

Erratum: "A Gravitational-wave Measurement of the Hubble Constant Following the Second Observing Run of Advanced LIGO and Virgo" (2021, ApJ, 909, 218)

[no abstract available

Rancang Bangun Data Warehouse (Studi Kasus) di PDAM Kabupaten Cilacap

Accurate and fast decision making process is highly needed as information technology is advancing. Facilities to prepare, store and use crucial data is needed in strategic decision making process. These data processing facilities are crucial in storing all the necessary information accumulated by the company which later on can be summarized. Data Warehouse is highly needed to improve the company performance. The goal of this research is the create Data Warehouse based on the needs in PDAM in Cilacap Regency. The creation of Data Warehouse Architecture uses Framework Data Warehouse and the Database Cycle which is illustrated using the star schema with the objective to easily understand and use the available information. This development architecture is created based on the present operational condition of the company. Several things which must be noted are that it must be user friendly in its interface and information flexibility. The adopted method is the SDLC method which is divided into several stages: The planning phase needs assessment, solution and architectural design, construction, deployment and maintenance. The planning phase is done through the identification of problems, identifying the system objective and the feasibility study. The next phase is the analyzing of needs which is done by analyzing the current usage of information within the company, determining the user needs and the system. The software architectural design phase is done by designing the database system by creating the activity diagram, DFD, and persistent data. The construction phase is done through the system implementation and development in the form of prototype. The deployment phase is done through deploying the system that has been developed. The maintenance phase is done by maintaining the system by focusing on information and technology update. The final result as the presentation media is in the form of web-based system application development which creates the smooth work-flow and is engineered to be easily accessed with the purpose to get benefits from the sources of information. The system of strategic decision making process can be implemented quickly to give fast services as part of productive decision process

Coverage response modeling for auto base paints formulation

Response Surface Methodology (RSM) was used to investigate the effects of binder, solvent, and pigment concentrations on the coverage response. The optimum coverage response of the auto base paint formulated was 1.5m2. Statistical analysis of the results showed that the data were adequately fitted by a second-order polynomial model Analysis of variance (ANOVA) also showed that the interactions between the independent parameters (binder, solvent, and pigment) have significant effects on the response (coverage). Diagnostics case statistics indicated that, the optimum experimental value of the cover age equal that of the predicted. This showed a good relationship between the actual and predicted response as evidenced in the R2 value of 0.9204 and a standard deviation of 0.1 obtained

Dynamic Mechanical Properties and Surface Morphology of Glass/Jute/Kevlar Fibres reinforced Hybrid Composite

Communication in Physical Sciences, 2021, 7(4): 438-443 Authors: Elijah  Danladi*, Paul.A.P. Mamza, S.A. Yaro, M.T. Isa, E. R. Sadiku and S.S. Ray Received: 18 November 2021/Accepted 08 December 2021 The strength and application of polymers can significantly be affected by their mechanical properties, which indicates that measures aimed at altering their mechanical properties will also affect their strength and possible applications The purpose of this study is to investigate the dynamic mechanical properties of the glass/jute /Kevlar hybrid fibres reinforced polypropylene using dynamic mechanical analysis, (DMA) to establish the interfacial bond in relation to storage modulus, loss modulus and damping factor. The samples were prepared using Carver Press at a temperature of 190 oC and a pressure of 500 psi using 1 mm thin films of polypropylene. The results obtained showed that the hybrid composites have a poor interfacial bond which led to molecular motion as the temperature was increasing. The loss modulus was also high, likewise the damping factor. The Scanning Electron Microscope (SEM) micrograms also supported these findings by showing the delamination on impacted samples. These make the hybrid composite a good material for rigid body armor application