Estimation of the Quantity of Water in the Abandoned Underground Mine of Gold Fields Ghana Limited Tarkwa: A Potential Source to Augment Water Supply to Tarkwa Municipality

The Tarkwa district is an important gold mining area in the Southwestern part of Ghana. The main source of potable water supply to the Tarkwa Nsuaem Municipality is from the Bonsa River treatment plant managed by the Ghana Water Company Limited (GWCL). The River is under threat from serious contamination by illegal mining ("galamsey") activities within its catchment area. Consequently, the amount of water supplied to the Municipality has not kept pace with its growing population due to increasing treatment cost and supply difficulties. The need to find alternative and sustainable sources of potable water supply to augment that from GWCL to the Municipality has become imperative. A large void volume created as a result of the abandoned underground mine operated by Gold Fields Ghana Limited (GFGL), after its closure in 1999 has flooded. This potential water resource is being pumped out daily, and wasted, sometimes spilling-over to low lying areas around the mine when allowed to reach its decant level. This study estimated the quantity of water in the Abontiakoon Vertical Shaft (AVS) which is part of the large underground void using survey production figures and post-closure void filling parameters resulting in 2.8 x 106 m3 and 2.9 x 106 m3 respectively. The rate of recharge to the underground water was also estimated to ascertain the sustainability of the void water should it be considered for use by employing the model of predicting rebound on “void filling” basis and average dewatering rate before closure at 2 535 m3/day and 2 618 m3/day respectively; indicating that recharge to the AVS reservoir is about 6 x 106 gal/day or 30% of current daily water supply deficit in the TNM. The estimated potential volume of mine water in storage in the entire Tarkwa underground void is 32 x106 m3. Two samples of the mine water were taken in November 2011 and February 2015 for quality analysis, in order to have a fair knowledge of the water quality parameters. The quality of the underground water was found to be potentially good, and not likely to cause any health threats, or water quality problems. Depth sampling is recommended to determine the chemical profile of the reservoir. Keywords: Reservoir, Municipality, Bonsa River, Contamination, Tarkw

A Dynamic Proxy Oriented Approach for Remote Data Integrity checking along with Secure Deduplication in Cloud

In Cloud computing users store data over remote servers instead of computer�s hard drive. This leads to several security problems since data is out of the control of the user. So, to protect against the security attacks and to preserve the data integrity in the cloud, Huaqun Wang et.al proposed proxy oriented remote data integrity checking (RDIC). However, this scheme only focuses on one-way validation i.e clients have to know whether their files are stored integrally in the cloud. But this scheme does not address the problem of duplication which is essential with increasing demand for cloud storage. And as users are untrusted from the perspective of the server, there is a need to prove the ownership of the files. The proposed work considers the requirement of mutual validation. In this paper we propose a new construction of Identity based RDIC along with secure deduplication. The proposed scheme avoids burden of complex key management and flexible as it support anyone to verify the contents of the data apart from the data owner and incurs less computation cost as token generation is done by the proxy instead of user

digital design and wooden architecture for arte sella land art park

Digital design is increasingly sinking the construction sector, shaping and validating architecture according to various criteria and introducing the wood industry to the 4.0 approach. Within the study entitled "Architecture at Arte Sella", parametric design, structural validations and CNC procedures are exploited to help define, control and assess several architectural woodworks, created with famous designers. This contribution describes the design and construction experiences of Atsushi Kitagawara (2017) and Kengo Kuma (2018–2019), the two masterpieces installed in the land art park of Arte Sella (Trento, Italy) and developed, thanks to the Politecnico di Milano team, from design to mock-ups, testing and construction

The Geometry and Structural Analysis of the Gold Deposits of Chirano Mine

The Chirano Mine gold deposit is a typical example of a structurally controlled deposit developed along the Kumasi Basin and the Sefwi Belt margin structure. The area has undergone various regimes of structural deformations. Consequently, all the Chirano deposits are intimately associated with shears and faults along a single continuous structural corridor known as the Chirano Shear Zone (CSZ). The CSZ geometry has been categorised into three major zones namely: (i) Laminated veins in shears, (ii) Breccia and (iii) Ductile to brittle ductile zones. The shear veins trend NE-SW and N-S, are laminated and occur in the sheared fabric close to the footwall. Penetrative foliated zones varying from a few centimeters to several meters constitute the ductile to brittle-ductile structures. Gold grades are much higher within this zone. Analysis of cataclasis intensity recorded in drill core confirms a semi brittle form of deformation within the mineralised domain. The CSZ has different orientations in dip and strike from the south of the mining lease to the north. The subtle changes in orientation are deposit dependent. The structure has a sinuous shape and tends to pinch and swell. The current geometry and the distribution of stratigraphy and orebodies at Chirano is a manifestation of the complex interplay of magmatic and hydrothermal events in the area.  Keywords: Ductile, Brittle-Ductile, Breccia, Chirano Shear Zone, Chirano Lode Horizo

Effect of Hot Water Extraction on pyrolysis of tender coconut fruit biomass: kinetic and thermodynamic parameters

Effect of pre-treatment of tender coconut fruit bio-mass powder with hot water on physico-chemical properties and thermal degradation behavior were investigated. The physico-chemical parameters were evaluated using ASTM standard protocols. The thermal degradation behavior was studied at heating rates of 10, 15 and 20oC/min under inert (N2) atmospheric conditions using TG/DTG techniques. The activation energies at each heating rate were determined using Flynn-Wall-Ozawa (FWO), Kissinger-Akahira-Sunose (KAS), Starink, and Tang models. The pre-treatment with hot water improved the proximate and ultimate analyses parameters and calorific value. The higher heating values (HHV) for untreated and treated tender coconut fruit biomass were 18.57 and 21.26 kJ/kg, respectively. The values of activation energy (Eα) for the un-treated biomass powder were estimated to be 389.25, 397.81 and 398.77 and 397.97kJ/mol for FWO, KAS, Tang, and Starink models, respectively and for the treated biomass these were 125.43, 118.61, 118.99 and 118.94kJ/mol, respectively. On an average the Eα of the treated coconut biomass was nearly three times lower than that for the untreated biomass. The results indicated that pre-treatment with hot water improved the fuel characteristics and thermal degradation behavior of the tender coconut shell biomass. The water extract exhibited high COD and BOD values and might be used as the feed-stock for biogas generation

Liquid phase immunoassay utilizing magnetic marker and high Tc superconducting quantum interference device

We have developed a liquid phase immunoassay system utilizing a magnetic marker and a superconducting quantum interference device (SQUID). In this system, the magnetic marker was used to detect the biological material called antigen. The magnetic marker was designed so as to generate a remanence, and the remanence field of the markers that bound to the antigens was measured with the SQUID. The measurement was performed in a solution that contained both the bound and free (or unbound) markers, i.e., without using the so-called bound/free (BF) separation process. The Brownian rotation of the free markers in the solution was used to distinguish the bound markers from the free ones. Using the system, we conducted the detection of biological material called IgE without BF separation. At present, we could detect the IgE down to 7 pg (or 39 amol

Surgical strategy of abdominal aortic aneurysm with preoperative renal failure

Objectives:To determine the effect of preoperative renal failure on the outcome of patients suffering from infrarenal abdominal aortic aneurysm (AAA).Method:During the period from January 1979 to August 1995, 364 patients with AAA were admitted to our hospital and 323 underwent elective reapir. The patients were retrospectively analysed in three groups. Group I was composed of 273 patients with a normal renal function who underwent an aneurysm repair. Group II was composed of 50 patients who demonstrated a preoperative renal dysfunction (creatinine above 2.0 mg/dl or creatinine clearance below 40 ml/min) and underwent an operation, including three patients maintained on chronic haemodialysis. Group III was composed of 18 patients with a renal dysfunction who did not undergo repair, including one patient maintained on chronic haemodialysis.Results:The operative mortality rate of groups I and II were 0.4% and 2.0%, respectively, although no significant difference was observed. The incidence of postoperative cardiac and pulmonary complications were also comparable in two groups. No patients required acute haemodialysis. The 5-year survival rate of group II (44%) was significantly higher than that of group III (20%), and seven of the 18 patients (39%) in group III ultimately died of a rupture of the AAA.Conclusions:Patients with chronic renal failure can undergo an abdominal aortic aneurysm repair based on the same indications as those without renal failure

Responses of phytoplankton assemblages to iron availability and mixing water masses during the spring bloom in the Oyashio region, NW Pacific

Spring phytoplankton blooms play a major role in the carbon biogeochemical cycle of the Oyashio region, western subarctic Pacific, where the seasonal biological drawdown effect on seawater pCO 2 is one of the greatest among the world\u27s oceans. However, the bloom often terminates before depleting macronutrients, and the initiation and magnitude of the bloom is heterogeneous. We conducted a high resolution taxonomic and physiological assessment of phytoplankton in relation to the different physicochemical water masses of Coastal Oyashio Water (COW), Oyashio water (OYW), and modified Kuroshio water (MKW) in the Oyashio region from April to June 2007. Massive diatom blooms were found in April. Then, chlorophyll a concentration, cell abundance of diatom taxa, and the maximum photosystem II photochemical efficiency (F v /F m ) were positively correlated with the mixing ratios of COW, suggesting that the spring bloom in April was strongly affected by the intrusion of COW. In the OYW, intensive blooms occurred from the middle of May under low dissolved iron (DFe) concentration (\u3c 0.26 nM). Redundancy analysis showed that while diatom blooms accompanied by COW were related to DFe concentration, this was not the case in the OYW. These results indicated that diatoms in the OYW possess different iron adaptation strategies compared with diatoms in the water masses affected by COW. This led to the spatial heterogeneity of the Oyashio spring bloom. The results presented here demonstrate that water mass characterization with detailed assessments of phytoplankton taxonomy and physiological status can improve our understanding of marine ecosystems

Sterol Composition of the Indian Green Lipped Mussel Perna virdis

Sterol composition of green lipped mussel Perna virdis was analysed using GCMS. Cholesterol was found to be the dominant sterol (54.162% of the total sterol content). Other sterols such as Cholesta-5,22-dien-3-ol (3β), ergosta-5,22-dien-3-ol (3 β,22E, 24S),  26,26-dimethyl-5,24 (28)-Ergostadien-3β-ol, 26-nor-5cholesten- 3β-ol, stigmasterol and γ sitosterol were also detected. Presence of phytosterols like stigmasterol and γ sitosterol underlines high nutritional potential and food value of this bivalve mollusk