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Journal of Power and Energy Engineering 2020年第2期8卷 1-19页

作者： abubakar alkali Centre for Process Integration & Membrane Technology School of Engineering Robert Gordon University Aberdeen UK Department of Petroleum and Natural Gas Engineering Baze University Abuja Nigeria

The electroless plating of palladium and palladium alloy membranes is fast becoming an important and enabling technology. This is more so when juxtaposed with the rising demand for high purity hydrogen for applications particularly in proton exchange membrane fuel cells (PEMFC). The effect of process factors such as sensitization and activation during surface modification, concentration of the reducing agent, plating temperature, time, pH, additives, air aeration on plating efficiency, quality of the palladium film and deposit morphology is reviewed with the aim of identifying areas requiring further investigation. The paper also reviews how these process factors could be optimised for better plating efficiency and overall membrane quality. The concentration of the reducing agent has been identified as the limiting factor on plating efficiency albeit other process factors separately impact on the plating efficiency. Furthermore, bulk precipitation caused by concentration of the reducing agent has been identified as a major problem during electroless plating with hydrazine based plating baths. To ameliorate this problem, a multi step addition of the hydrazine reducer in separate portions has been recommended.

关键词： Electroless Plating Hydrogen Palladium Membranes Plating Efficiency Process Factors

A Comparison of the Inhibiting Effect of CO and CO2 to Hydrogen Permeation and n-Value in Pd and Pd/Ag Membranes Prepared on Alumina Support

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Journal of Power and Energy Engineering 2019年第12期7卷 1-14页

作者： abubakar alkali Karimatu Abdullahi School of Engineering Robert Gordon University Riverside East Aberdeen UK Department of Petroleum and Natural Gas Engineering Baze University Abuja Nigeria Department of Petroleum Chemistry Baze University Abuja Nigeria

The mitigation of the CO inhibition effect in palladium membranes is necessary due to its significance in the efficiency of membrane reactors and hydrogen production systems. In this work, the hydrogen separation performance of a Pd and Pd/Ag membrane both of thickness 2 μm is investigated using a mixed gas with composition (H2 = 50%, CO = 28%, CO2 = 10%, CH4 = 8%, N2 = 4%) at temperature 623 - 873 K and pressure (0.05 - 0.4 bar) was investigated. The component gases CO and CO2 were observed to inhibit hydrogen permeation through the membrane and lead to deviations from Sievert’s law for n values 0.55 and 0.62 for the Pd membrane and unity for the Pd/Ag membrane. For the Pd/Ag membrane, the concentration of CO in the permeate stream was reduced as a result of the addition of Ag. The effect of the component gases to hydrogen permeation was observed to be lower for the Pd/Ag membrane. Annealing the membrane in hydrogen at high temperature decreased the inhibition effect and enhanced hydrogen permeation through the membrane.

关键词： Membrane Separation Palladium Membranes CO Inhibition Hydrogen Permeation n-Value Electroless Plating Alternative Energy Gas Permeation

Preliminary Evaluation of Soils from Kwalkwalawa （Sokoto） and Bakolori （Talata Mafara） Regions Used for Rice and Fishing Activities

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Journal of Agricultural Science and Technology(B) 2015年第4期5卷 247-251页

作者： abubakar Baba Misau Lawali abubakar Lawali alkali Argungu Department of Animal Production Faculty of Agriculture and Agricultural Technology Abubakar Tafawa Balewa University P.M.B. 0248 Bauchi 74241 Nigeria Department of Crop Science Usman Danfodio University (UDU) Sokoto 840212 Nigeria Department of Forestry and Fisheries Usman Danfodio University (UDU) Sokoto 840212 Nigeria

Kwalkwalawa is an area noted for extensive rice production and fishing activities, while Talata Mafara is a site used mainly for rice production. Soils of the two areas were taken and evaluated for potentialities of rice-cum-fish culture. Three replicate soil samples were collected in October 2004 and 2005 from three sampling sites within the study area at 0-15 cm and 15-30 cm depth. Analysis of the samples indicated that at Kwalkwalawa the soil pH was 7.35 and 7.28 for 0-15 cm and 15-30 cm depth, respectively, and 6.75 and 6.67 for Talata Mafara, respectively, during 2004. During 2005, the pH at Kwalkwalawa was 6.75 and 7.18, while at Talata Mafara ranged between 5.63 and 5.14. Organic carbon content at Kwalkwalawa estimated during 2004 was 1.12 g/kg and 0.81 g/kg for 0-15 cm and 15-30 cm, whereas at Talata Mafara amounted 0.93 g/kg and 0.11 g/kg. During 2005, noted values of organic carbon at Kwalkwalawa lowered to 0.45-0.28 g/kg and at Talata Mafara lowered to 0.38-0.06 g/kg. Total nitrogen （N） at Kwalkwalawa during 2004 was 0.04 g/kg and 0.03 g/kg for 0-15 cm and 15-30 cm, at Talata Mafara it was both 0.04 g/kg for both depths. During 2005, at Kwalkwalawa, total N was 0.04 g/kg and 0.03 g/kg, and at Talata Mafara it was 0.05 g/kg for both depths. Available phosphorus （P） at Kwalkwalawa during 2004 was 1.93 mg/kg and 2.03 mg/kg for 0-15 cm and 15-30 cm, at Talata Mafara it was 1.59 mg/kg and 1.63 mg/kg. During 2005, available P was 5.82 mg/kg and 6.13 mg/kg for Kwalkwalawa and 1.67 mg/kg and 1.91 mg/kg for Talata Mafara, at 0-15 cm and 15-30 cm, respectively. Analysis of clay content indicated that at Kwalkwalawa the clay content was 11 g/kg for both depths during 2004 and 16.5 g/kg during 2005, and the soil texture was classified as sandy loam during both seasons. At Talata Mafara during 2004, the clay content was 73 g/kg and 93 g/kg for 0-15 cm and 15-30 cm. During 2005, it was 84 g/kg and 103 g/Kg. The soil was classified as loamy sand after fitting it into te

关键词： Evaluation soils rice fish culture.

Assessment of the Level of Knowledge of the Nature of Highly Pathogenic Avian Influenza Demonstrated by the Nigerian Veterinary Laboratory Staff Involved in HPAI Diagnosis in Nigeria

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Open Journal of Veterinary Medicine 2015年第4期5卷 89-92页

作者： Bello Rabi’u alkali Kyauta Bulus Tanyigna Yahaya abubakar Yabo Department of Veterinary Microbiology Usmanu Danfodiyo University Sokoto Nigeria National Institute for Policy and Strategic Studies (NIPSS) Kuru Jos Nigeria Department of Veterinary Physiology and Biochemistry Usmanu Danfodiyo University Sokoto Nigeria

The study was designed to evaluate the level of knowledge of Nigerian Veterinary Laboratory Staff on the nature of Highly Pathogenic Avian Influenza (HPAI) disease using structured questionnaires. The study comprised the Staff of National Veterinary Research Institute (NVRI) and five reference Veterinary Teaching Hospitals (VTH) designated for HPAI diagnosis. A total of 69 questionnaires were distributed to the laboratory staff. Questions on the general nature of the disease such as the cause, signs, mode of transmission, methods of identification, lesions, control and prevention, etc. were asked. The results showed that 77.38% of the staff answered all the questions correctly indicating their considerable knowledge of the HPAI disease. Considerable percentage of the staff listed correctly the equipment used for serology (36.23%) and RT-PCR (31.88%). Interestingly only 13.04% of the staff listed correctly the equipment used in rapid tests despite the fact that they are simpler and recommended for all P2 laboratories. In conclusion, the veterinary laboratory staff assessed demonstrated a significant level of knowledge on HPAI diagnosis;however, most of their laboratories lack the structure, organization, funds and basic facilities required for effective HPAI diagnosis.

关键词： Assessment Veterinary Laboratory Highly Pathogenic Avian Influenza

Haematological Profile of Pregnant Women Attending Antenatal Clinic in Bauchi, Nigeria

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Open Journal of Obstetrics and Gynecology 2020年第12期10卷 1776-1787页

作者： abubakar Saidu Kadas Kenneth Okwong Okon Calvin Chama Mohammed alkali Yusuf Bara Jibrin Sulayman Tunde Balogun Mohammed Aminu Baffa Lamaran Makama Dattijo abubakar Shehu Department of Obstetrics and Gyneacology Abubakar Tafawa Balewa Teaching Hospital Bauchi Nigeria Department of Medical Microbiology Federal Medical Centre Makurdi Nigeria Department of Internal Medicine Abubakar Tafawa Balewa Teaching Hospital Bauchi Nigeria Department of Clinical Pharmacology and Therapeutics College of Medical Sciences University of Maiduguri Maiduguri Nigeria

Introduction: Haematological profile of pregnant women provides vital information on physiological changes in pregnancy progress, outcome and possible maternal-foetal complications. The study assessed the haematological profile of pregnant women attending the antenatal clinic. Methodology: The cross-sectional study was conducted at the antenatal clinic of Abubakar Tafawa Balewa Teaching Hospital, Bauchi between July and September 2018 among pregnant women attending the antenatal clinic. Study participant was recruited on voluntary basis and study questionnaire and informed consent administered. Blood samples are collected and analysed using System x haematology autoanalyser. Result: A total of 191 study participants comprised of 141 pregnant women at different trimester stages and 50 non-pregnant. Mean haematocrit, haemgloblin, white blood count and platelet count of 35.8 ± 9.0, 11.6

关键词： Heamatological Profile Pregnant Women Antenatal Clinic Bauchi Nigeria

Approach to Calibrated Simulation Tool for Improved Building Performance

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Approach to Calibrated Simulation Tool for Improved Building...

Low Level of Hepatitis B Surface Antigen Screening in a Tertiary Health Facility in Nigeria 2000-2014: Imperative for Provider Initiated Testing and Counselling for Hepatitis B Virus?

The 2nd International Conference on Green Building Technologies and Materials(GBTM2012)

作者： Suleiman Alivu Shika Maimunah Sapri Ibrahim Sipan alkali Ibrahim abubakar Aminu Umar Usman Bukar Wakawa Center for Real Estate Studies Faculty of Geoinformation and Real Estate81310Universiti Teknologi Malaysia Department of Architecture Faculty of Built Environment81310Universiti Teknologi Malaysia

Simulation tools represent continuous,stochastic processes in buildings by discrete timestep, deterministic model *** models make assumptions when representing real *** models more closely represent the operation of the real building and allow Energy Conservation Measures(ECM) to be investigated at finer resolution,using fewer *** paper presents a systematic,evidence-based approach to calibrated simulation. This approach yields a calibrated model that is based solely on referenced sources of information about the *** proposed methodology builds on some of the best techniques from the reviewed literature and combines these with an evidence-based approach that uses version control software to track the calibration *** the process produces a single,deterministic model for an inherently stochastic process(building operation),such an approach can produce meaningful conclusions where sub-utilities hourly measured data and significant resources for further investigation and measurement are available.

关键词： Energy Existing buildings Simulation Tools

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Open Journal of Epidemiology 2020年第3期10卷 251-264页

作者： Elon Warnow Isaac Iliya Jalo Yaya Saidu alkali Ayomikun Ajani Joshua Difa abubakar John Tunde Aremu Christianah Oluwaseun Oyeniyi Mohammed Hassan Danlami Department of Paediatrics College of Medical Sciences Gombe State University Gombe Nigeria Department of Paediatrics Federal Teaching Hospital Gombe Nigeria Department of Community Medicine College of Medical Sciences Gombe State University Gombe Nigeria Department of Medicine Federal Teaching Hospital Gombe Nigeria Infectious Diseases Training and Research Group Gombe Nigeria Department of Molecular Microbiology Federal Teaching Hospital Gombe Nigeria

Introduction: Viral hepatitis is a major public health challenge that requires an urgent response. Reducing mortality requires major scale-up in prevention, testing and treatment access;coverage in HBV vaccination, testing and treatment is low and must accelerate massively to achieve the 2030 targets. Less than 1% of HBV-infected individuals are diagnosed in Sub-Sahara Africa, despite the availability of rapid tests with good diagnostic accuracy. Materials and Methods: This was retrospective cross sectional study conducted in Federal Teaching Hospital Gombe, in North East Nigeria. All children and adults who presented to the out-patient departments, and those that were admitted irrespective of their HIV and or Hepatitis C virus status and had Hepatitis B and/or Hepatitis B envelope antigen test were conducted between 2000 to 2015. All children and adults were tested using the Hospital standard for Hepatitis B surface antigen test strip. Results: Between 2000 and 2014, 739,456 children and adults were admitted and reviewed in the outpatient units of the Federal Teaching Hospital Gombe;there were 685,552 adults and 53,904 children. Children constituted 7.3% (53,904/739,456) of admissions and outpatient consultations. 2.8% (210/7570), 3.3% (773/23,783), 3.6% (1145/32,142), 5.2% (1694/33,043), 3.3% (986/29,216), 1.9% (661/3321), 0.1% (53/41,626), 0.2% (113/46,634), 2.6% (1418/54,423), 5.4% (3717/69,696), 3.7% (2332/62,086), 3.5% (3241/90,623), 3.2% (2881/89,398), 3.8% (2428/62,687), 2.8% (1835/63,208) of children and adults were tested for HBsAg in 2000, 2001, 20002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 and 2014 respectively. 23,487 children and adults were tested for HBsAg with a cumulative testing rate of 3%. Overall 4465/23,487 children and adults were seropositive for HBsAg giving a cumulative prevalence of 19%. Conclusion: HBV screening in our health facility is very low

关键词： Hepatitis B Testing Provider Initiated Counseling and Testing Sub-Saharan Africa

Electrical and Dielectric Characterization of Na0.5Li0.5Zr2(PO4)3

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Open Journal of Physical Chemistry 2011年第3期1卷 94-103页

作者： Umaru Ahmadu Kasim Uthman Isah abubakar Ohinoyi Musa Tomas Salkus 不详

Na0.5Li0.5Zr2(PO4)3has been synthesized by solid state reaction and characterized by thermogravimetry/ differential thermal analyses (TGA/DTA) in the temperature range 300 - 1573 K. X-ray diffraction measure- ments have been carried out to determine the phase of the composition and scanning electron microscopy (SEM) for microstructure evaluation. Impedance spectroscopy at different temperatures (310 - 600 K) and frequencies (300 kHz - 1 GHz) have been carried out and the dielectric relaxation behaviour was determined under the same conditions. A dc conductivity maximum value of 0.25 S/m at 580 K was observed. However, the mixed alkali effect was not observed. The material exhibited relaxation behaviour with a peak in the dielectric permitivity at 469 K. There were no structural transformations observed.

关键词： NZP Impedance Spectroscopy Dielectric Relaxation Electrical Conductivity

Sero-Prevalence of H. pyloriAntibodies among Asymptomatic Rural Population in Bauchi State, Nigeria—A Preliminary Study

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Open Journal of Gastroenterology 2020年第11期10卷 301-310页

作者： Mohammed alkali Kenneth O. Okon Yusuf B. Jibrin Sabo Umar Abdulrazak Toyin Godiya I. Darie Farouk Buba Sulayman T. Balogun Binta Lasan Department of Internal Medicine Abubakar Tafawa Balewa University Teaching Hospital Bauchi Nigeria Department of Medical Microbiology Federal Medical Centre Makurdi Nigeria Department of Chemical Pathology Abubakar Tafawa Balewa University Teaching Hospital Bauchi Nigeria Department of Medicine College of Medical Sciences University of Maiduguri Maiduguri Nigeria Department of Clinical Pharmacology and Therapeutics College of Medical Sciences University of Maiduguri Maiduguri Nigeria Department of Microbiology Abubakar Tafawa Balewa University Teaching Hospital Bauchi Nigeria

Helicobacter pylori infection is a major public health problem globally, with high prevalence in developing countries associated with poor sanitation, low standard of living, urban-rural disparity and increased gastrointestinal pathologies. This preliminary study determined the seroprevalence of H. pylori infection among asymptomatic rural population and association of sociodemographic variables on the result outcome. A total of 250 asymptomatic volunteered participants were screened for H. pylori antibodies, using rapid immunochromatographic strips. 44.8% (112/250) were seropositive, and showed increased prevalence with the age group, years (8.0%), 18 - 39 years (23.5%) and 40 -

Low Level of Hepatitis B Surface Antigen Screening in a Tertiary Health Facility in Nigeria 2000-2014: Imperative for Provider Initiated Testing and Counselling for Hepatitis B Virus?

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