Natural Science Journal of Xiangtan University最新文献

{"title":"Geochemical Signatures of Bara Basin Aquifers, Kordofan State, Sudan","authors":"S. H. Mohamed, Hamed Mangoshi Mangoshi, Salah M. Mahgoub, Abuagla Y. Ahmed","doi":"10.47941/nsj.1222","DOIUrl":"https://doi.org/10.47941/nsj.1222","url":null,"abstract":"Purpose: In this paper, geochemical investigation has been carried out to study the concentrations of major cations; Sodium (Na+), Potassium (K+), Magnesium (Mg2+), and Calcium (Ca2+), and major anions; Chloride (Cl-), Bicarbonate (HCO3-), Nitrate (NO3-) and Sulphate (SO42-), other parameters such as (pH), Electric conductivity and T.D.S were also studied in all water samples taken from wells in Bara basin. \u0000Methodology: Forty five (45) water samples have been collected from wells. Lab works were done at Groundwater and Wadis Directorate (GWD), Khartoum State according to Sudanese Standards and Metrology Organization, (2002), to study the major cations and major anions. \u0000Findings: The results revealed that the average value of pH was (7.9) E.C values were (843.4 μS/cm) and T.D.S values were (59 mg/l). The average concentrations of the major cations obtained were; Na+ (126.3), K+ (5.22), Mg2+ (28.30), Ca2+(66.41) and the major anions (mg/l) were; Cl- (159.00), HCO3- (165.30), NO3- (156.70) and SO42- (164.70). The (Na/Cl) ratio is (2.47) is also high which reflects the abundance of (Na+) ions relative to the Chloride (Cl-) ions which confirmed the light-salty nature of groundwater. Geochemical mass balance calculations indicate that upper aquifer is mainly affected by the dissolution and dolomitization processes of major anions. \u0000Unique Contribution to Theory, Policy and Practice: This process is highly developed in the central west part of the basin due to the abundance of Sulphate (SO42-), Bicarbonate (HCO3-), Magnesium (Mg2+), and Calcium (Ca2+) ions. High values of E.C, T.D.S, Ca2+, and SO42- are mainly presents as a saline water resource  in some villages. Two types of water are  classified  here these are : i). Na-HCO3 type  and ii). Ca- Cl -SO4 type. The study concluded that water samples from Almakser, Hamdan-2, Um-Zeeraga-2, and Al-Zareeba-2 villages have very high concentrations of  E.C, T.D.S Ca2-, Cl-, NO3- and SO42-, which may suggest that water samples are not fit for human consumption, according to guidelins by W.H.O (1984). This paper recommends further study on  water quality.","PeriodicalId":18894,"journal":{"name":"Natural Science Journal of Xiangtan University","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85290924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TiO2–CU Thin Film Material for Optical Hydrogen Gas Sensor Applications","authors":"Joseph Kamau Kamau","doi":"10.47941/nsj.1011","DOIUrl":"https://doi.org/10.47941/nsj.1011","url":null,"abstract":"Purpose: Several scientific researches are underway to investigate the possibility of using various green energies. Hydrogen gas is a candidate of such research, since its use as a fuel in automobiles releases pure water, a recyclable biproduct. But, the leakages of the gas are detrimental to its application due to its low auto ignition energy of 20 μj, wider air flame limit of 4-75 % and high flame velocity of 3.46 ms-1. This study involved fabrication of an optical gas sensor for sensing the leakage levels of hydrogen gas to a surrounding. \u0000Methodology: Titanium dioxide thin films of thicknesses 47.7, 56.2, 82.3, 100.4 and 120.5 nm were deposited on both microscope and FTO glass slides using DC magnetron sputtering technique and characterized as primate and annealed at 400 and 500oC. Copper (Cu) catalytic layers of 5.6, 10.2, 17.3 and 21.0 nm were deposited using EDWARDS AUTO 306 Magnetron sputtering system on an optimized 100.4 nm TiO2 sample, annealed at 400oC. Optical properties were deduced from transmittance and absorbance spectra measured using 1800 Shimadzu spectrophotometer in the optimum range of 280-800 nm through simulation. The optical behavior of the films was generated using SCOUT software and analyzed using ORIGIN 9.1 64-bit software. \u0000Results: The energy band gap decreased with material thickness from 4.2±0.05 eV for 47.7 nm film to 3.9±0.05 eV for 100.4 nm films. 120.5 nm films showed higher energy gap of 4.0±0.05 eV. Transmittance decreased with increase in thickness probably due to agglomeration of film particles. The energy gap of the 100.4 nm, TiO2 thin films annealed at 400oC was 3.9±0.05 eV. This is a material quality of the anatase phase. The copper surface layer increased absorption in the higher wavelength region. The energy band gaps were reduced from 3.9 to 3.8±0.05 eV with increased coverage. Self-limiting at 17.3 nm copper overlayer realized increased energy gap to 4.1±0.05 eV. A lower energy band gap range of 3.9-3.8±0.05 eV was realized when FTO substrates were used. The transmittance decreased with increased H2 gas concentration. The optical energy gap reduced from 4.1±0.05 eV in 0 ccm to 3.9±0.05 eV in 50 ccm of hydrogen gas concentration. The sensitivity increased from 0.3 % in 0ccm to 3.9 % in 50 ccm hydrogen gas concentration. An average sensitivity of 2.0 % was realized for films fabricated on FTO substrate. This is higher than 1.7 % reported earlier. The material gas sensing potential was done at room temperature. The fabricated sensor material showed higher sensitivity and lower temperature operation and is furthermore, expected to be cheaper and safer \u0000Unique Contribution to Theory, Policy and Practices: Though, in order to realize a more portable stand-alone gas sensor, an investigation on an ideal photon type source that incorporates the material is recommended. Further, extension of this study on structure and morphology of the film is essential to understand its sensing behavior.","PeriodicalId":18894,"journal":{"name":"Natural Science Journal of Xiangtan University","volume":"121 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73566060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"EVALUATION OF COW BONE AND SNAIL SHELL FOR SURFACE TREAMENT OF LOW CARBON STEEL","authors":"Oinu Timothy Oinu, D.T. Gundu Gundu, G. Nyior","doi":"10.47941/nsj.932","DOIUrl":"https://doi.org/10.47941/nsj.932","url":null,"abstract":"Purpose: In this study, selected calcareous wastes (cow bone and snail shell) were evaluated for use in surface carburizing of low carbon steel. \u0000Methodology: Pack carburization process was used for the surface hardening of mild steel at 800 oC as the carburizing temperature. The soaking period of 2 hours was used and water was used as quenching medium. The specimens were subsequently tempered at 500. Mechanical tests such as hardness, impact, microstructural and wear resistance were carried out on the samples using standardized methods. \u0000Results: The results obtained showed that the sample carburized with snail shell gave a higher hardness value than sample carburized with cow bone and untreated sample. In the charpy impact test carried out, it was observed that the sample carburized by snail shell has higher energy value than sample carburized with cow bone. For microstructural analysis test, it was seen that sample carburized by cow bone gave equiaxed and finer grains than sample carburized with snail shell and untreated sample, and for wear rate test, sample carburized by snail shell, has a better wear rate than sample carburized by cow bone and untreated sample.","PeriodicalId":18894,"journal":{"name":"Natural Science Journal of Xiangtan University","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89433898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phytochemical and Antimicrobial Activity of Piperine Extract and Essential Oil of Piper nigrum Leaves","authors":"O. I. Ojo, Ezenwa Valentine Chukwuma, A. Ezeike, Adedayo Adedayo","doi":"10.47941/nsj.732","DOIUrl":"https://doi.org/10.47941/nsj.732","url":null,"abstract":"Phytochemical and antimicrobial activities of the Piperine extract and essential oil extract from Piper nigrum leaves were evaluated. The phytochemicals were determined using Harborn standard qualitative and quantitative analysis methods. The antimicrobial assay was carried out using agar well diffusion method and the test organisms were Staphylococcus aureus, Salmonella spp, E. coli and Aspergillus spp. The study revealed that the flavonoid, tannin, saponin, glycosides, phenol, and alkaloids content  of Piperine extract of Piper nigrum are as follows 1.1 % ± 0.1, 71.58 mg/l ±0.1, 1.4 % ± 0.4, 4.7 % ± 0.03, 7.59 mg ± 0.1 and 1.5 % ± 0.3 respectively. The antimicrobial assay of Piperine extract showed zones of inhibition for Staphylococcus aureus , Salmonella spp, E. coli  and Aspergillus spp  are as follows: 18.0 mm, 19.0 mm, 21.0 mm and 18.0 mm respectively. While zone of inhibition for the essential oil for Staphylococcus aureus, Salmonella spp, E. coli and Aspergillus spp  are as follows:  33.0 mm, 40.0 mm, 47.0 mm and 8.0 mm respectively. The result obtained from this study shows that essential oil has more zone of inhibition than Piperine extract leaves and this indicates that essential oil can be more effective in the treatment of disease caused by all these organisms.","PeriodicalId":18894,"journal":{"name":"Natural Science Journal of Xiangtan University","volume":"128 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79149229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"EVALUATION OF SELECTED DRINKING WATER QUALITY PARAMETERS USING CCME-WQI IN NAKURU MUNICIPALITY, KENYA","authors":"Margaret Mwikali Keli, T. Munyao, E. Kipkorir","doi":"10.47941/nsj.678","DOIUrl":"https://doi.org/10.47941/nsj.678","url":null,"abstract":"Purpose: Reliable baseline information on overall quality status of drinking water at spatial and temporal scales is important in drinking water management systems, ensuring access to clean and safe drinking water. The study aimed at determining the suitability of natural and treated water for drinking in Nakuru Municipality, Kenya. An attempt was also made to explore the applicability of CCME-WQI (Canadian Council of Ministers of the Environment Water Quality Index) in evaluation of groundwater quality data for drinking uses. \u0000Methodology: The study adopted a stratified random sampling technique that was employed systematically in conjunction with point and line techniques to create stratas/sampling components while ensuring each water cluster was represented through the sampling process. Analytical values of electrical conductivity, pH, selenium, cadmium, chloride and fluoride were used to determine quality status of water sourced from river and boreholes and as input parameters in calculation of index values. The evaluation and characterization of natural borehole water quality for drinking purposes was made using the water quality index (WQI) of the Canadian Council of Ministries of the Environment (CCME). \u0000Results: The quality of natural and treated drinking water was found to be fresh in pH, chloride and electrical conductivity but contaminated in selenium, cadmium and fluoride in line with respective regulatory standards for drinking water. Based on the CCME-WQI, index values for all sampled sites representing natural borehole water were calculated in a range of 29.83 to 37.71 with an average value of 31.05 and ranked as poor. \u0000Unique contribution to theory, practice and policy: Considering the limitations associated with the conventional methods in water quality monitoring, there is need to utilize other scientific based methods that can fill in the gaps to improve the current state of governance and practice of drinking water management systems. The CCME-WQI method as applied in this study can be utilized in evaluation of water quality monitoring data to facilitate water resources operational management and their allocation for different uses.","PeriodicalId":18894,"journal":{"name":"Natural Science Journal of Xiangtan University","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87667307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"LAMINAR HEAT TRANSFER WITH VISCOUS DISSIPATION FOR NEWTONIAN FLUIDS FLOWING IN PARALLEL HEATED PLATES WITH ONE PLATE MOVING","authors":"M. U. Uwaezuoke","doi":"10.47941/nsj.345","DOIUrl":"https://doi.org/10.47941/nsj.345","url":null,"abstract":"The paper investigates basic analytical expressions for Nusselt number with effect of viscous dissipation on the heat transfer between parallel heated plates with one plate moving, where the focus is on hydro-dynamically and thermally fully developed flow of Newtonian fluids with constant properties, neglecting the axial heat conduction in the fluids and through the walls. Thermal boundary conditions considered are: both plates kept at different constant heat fluxes, both plates kept at equal constant heat fluxes, and one plate insulated. From the analysis, new expressions for Nusselt numbers have been found, as a function of various definitions of the Brinkman number.","PeriodicalId":18894,"journal":{"name":"Natural Science Journal of Xiangtan University","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90757612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The theory of the perturbation for Landau-Ginzburg-Higgs equation","authors":"Pan Liu-xian, Zuo Wei-ming, Yan Jia-ren","doi":"10.7498/aps.54.1","DOIUrl":"https://doi.org/10.7498/aps.54.1","url":null,"abstract":"The first-order and second-order effects of perturbation on Landau-Ginzburg-Higgs Soliton have been derived,namely,both the slow time-dependence of the soliton parameters and the first-order and second-order correction has been obtained.","PeriodicalId":18894,"journal":{"name":"Natural Science Journal of Xiangtan University","volume":"28 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2004-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72904725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Superconvergence of Least-Squares Mixed Finite Element Approximations Over Quadrilaterals","authors":"Yanping Chen, Manping Zhang","doi":"10.1007/978-1-4615-0113-8_9","DOIUrl":"https://doi.org/10.1007/978-1-4615-0113-8_9","url":null,"abstract":"","PeriodicalId":18894,"journal":{"name":"Natural Science Journal of Xiangtan University","volume":"24 1","pages":"135-144"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90406083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}