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The Effect of Relative Humidity on Maritime Tropical Aerosols

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Open Journal of Applied Sciences 2014年第6期4卷 299-322页

作者： bello idrith tijjani Fatima Sha'aibu Aliyu Aliyu Department of Physics Bayero University Kano Nigeria Department of Science Laboratory Technology School of Technology Kano State Polytechnic Kano Nigeria Girl’s Science and Technical College Kano Nigeria

The present work focused on the effect of relative humidity (RH) on some microphysical and optical properties of maritime tropical aerosols from the software package OPAC (Optical Properties of Aerosols and Clouds) data at the spectral range of 0.25 μm to 2.5 μm and eight relative humidities (0%, 50%, 70%, 80%, 90%, 95%, 98%, and 99%). The microphysical properties extracted were radii, volume mix ratio, number mix ratio and mass mix ratio as a function of RH while the optical properties were optical depth, extinction, scattering and absorption coefficients single scattering albedo, refractive indices and asymmetric parameters. The hygroscopic growth and enhancement parameters were then parameterized by using some models to determine the hygroscopicity, bulk hygroscopicity, humidification factors and some other parameters that depend on RH and/or wavelengths. The results showed that the data fitted our models very well and can be used to extrapolate the hygroscopic growth at any RH and enhancement parameters at any RH and wavelengths. The importance of determining gfmix(RH) as a function of RH and volume fractions, mass fractions and number fractions, and enhancement parameters as a function of RH. The effective radii increases with the increase in RH, while Angstrom coefficients decrease with the increase in RH and this signifies the dominance of coarse mode particles. The angstrom coefficients show that the mixture has bimodal type of distribution and the mode size increases with the increase in RH.

关键词： Microphysical Properties Optical Properties Hygroscopic Growth Parametrization Enhancement Parameters Angstrom Coefficients Effective Refractive Indices

The Effect of Relative Humidity on Continental Average Aerosols

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Open Journal of Applied Sciences 2014年第7期4卷 399-423页

作者： bello idrith tijjani Aliyu Aliyu Fatima Sha’aibu Department of Physics Bayero University Kano Nigeria Department of Science Laboratory Technology School of Technology Kano State Polytechnic Kano Nigeria Girl’s Science and Technical College Kano Nigeria

In this paper, the authors extracted and investigated the effect of relative humidity (RH) on some microphysical and optical properties of continental polluted aerosols from OPAC (Optical Properties of Aerosols and Clouds) at the spectral range of 0.25 μm to 2.5 μm and eight relative humidities (0%, 50%, 70%, 80%, 90%, 95%, 98%, and 99%). The microphysical properties extracted were radii, volume, number and mass mix ratios as functions of RH while the optical properties were optical depth, extinction, scattering and absorption coefficients single scattering albedo, refractive indices and asymmetric parameters also at eight RHs. Using the microphysical properties, effective hygroscopic growth factors and effective radii of the mixtures were determined while using optical properties we determined the enhancement parameters, effective refractive indices and angstrom coefficients. Using the effective hygroscopic growth, we determined the dependence of the effective hygroscopicity parameter as a function of RH, while using enhancement parameters;we determined the effect of humidification factor on RH and wavelengths. The effective hygroscopic growth and enhancement parameters were then parameterized using some models to determine the effective hygroscopicity parameter, bulk hygroscopicity and humidification factors. We observed that the data fitted the models very well. The effective radii decrease with the increase in RH while the effective hygroscopic growth increases with the increase in RH, and this is in line with the increase in angstrom parameters, and this shows increase in mode size with the increase in RH. The angstrom coefficients show that the mixture has a bimodal type of distribution with the dominance of fine mode particles.

关键词： Microphysical Properties Optical Properties Hygroscopic Growth Parametrization Enhancement Parameters Angstrom Coefficients Effective Refractive Indices

Numerical Analysis of the Analytical Relationships between Angstrom Coefficients of Aerosols and Their Optical Properties for Four Types of Aerosols

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Open Journal of Applied Sciences 2013年第8期3卷 490-513页

作者： idrith tijjani bello Sha’aibu Uba Salman Koki Fatima Department of Physics Ahmadu Bello University Zaria Nigeria Department of Physics Bayero University Kano Nigeria

In this paper, the authors numerically analyzed the analytical relationships between angstrom coefficients and optical properties of aerosols to the existing data extracted from OPAC at the spectral length of 0.25 μm to 2.5 μm at eight relative humidity for desert, urban, marine clean and continental clean aerosols. That is apart from their relationships with the wavelength that was determined, in this paper their relation with respect to aerosols’ type and RHs are determined. The properties extracted are scattering, absorption, and extinction coefficients and single scattering albedo. The results showed that the extinction and single scattering albedo are correct for all the aerosols but single scattering co-albedo is satisfied for only sahara and continental clean.

关键词： Angstrom Coefficients Analytical Relationships Parameterize Wavelength Dependence Optical Properties

Origin and depositional environments of source rocks and crude oils from Niger Delta Basin: Carbon isotopic evidence

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China Geology 2020年第4期3卷 602-610页

作者： Abiodun B Ogbesejana Oluwasesan M bello tijjani Ali Department of Applied Chemistry Federal University Dutsin-MaP.M.B.5001Dutsin-MaKatsina StateNigeria

Thirty-nine crude oils and twenty-one rock samples from Niger Delta Basin,Nigeria have been characterized based on their isotope compositions by elemental analysis-isotope ratio mass spectrometry and gas chromatography-isotope ratio mass *** bulk carbon isotopic values of the whole rock extracts,saturate and aromatic fractions range from–28.7‰to–26.8‰,–29.2‰to–27.2‰and–28.5‰to–26.7‰,respectively while the bulk carbon isotopic values of the whole oils,saturate and aromatic fractions range from–25.4‰to–27.8‰,–25.9‰to–28.4‰and–23.5‰to–26.9‰,*** average carbon isotopic compositions of individual alkanes(nC12-nC33)in the rock samples range from–34.9‰to–28.2‰whereas the average isotopic values of individual n-alkanes in the oils range from–31.1‰to–23.8‰.Theδ13C isotope ratios of pristane and phytane in the rock samples range from–29.2‰to–28.2‰and–30.2‰to–27.4‰respectively while the pristane and phytane isotopic values range from–32.1‰to–21.9‰and–30.5‰to–26.9‰,*** isotopic values recorded for the samples indicated that the crude oils were formed from the mixed input of terrigenous and marine organic matter and deposited under oxic to sub-oxic condition in lacustrine-fluvial/deltaic *** stable carbon isotopic compositions were found to be effective in assessing the origin and depositional environments of crude oils in the Niger Delta Basin.

关键词： Crude oils Source rocks Isotopic compositions Origin Niger Delta Basin Depositional environment Nigeria

Geochemical significance of tricyclic and tetracyclic terpanes in source rock extracts from the Offshore Niger Delta Basin,Nigeria

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Acta Geochimica 2021年第2期40卷 184-198页

作者： Abiodun B.Ogbesejana Oluwasesan M.bello tijjani Ali Uduma A.Uduma Kamaluddeen S.Kabo Oluwadurotimi O.Akintade Department of Applied Chemistry Federal University Dutsin-MaP.M.B.5001Dutsin-MaKatsina StateNigeria Department of Chemical Sciences Koladaisi UniversityIbadanOyo StateNigeria

Tricyclic and tetracyclic terpanes are important constituents of crude oil and source rock ***,they have not been reported in the Offshore Niger Delta Basin,***,the present study investigated the geochemical significance of tricyclic and tetracyclic terpanes in source rock extracts from the Offshore Niger Delta Bain,Nigeria with gas chromatography-mass spectrometry(GC-MS).The total relative abundances of tricyclic terpanes,C_(19)TT-C_(21)TT,and C_(23) TT in the rock samples ranged from 82.50 to 96.37%,50.08 to 74.17%,and 25.83 to 49.92%,*** values showed the source rocks were formed from a mixed origin(terrestrial and marine).Among the tricyclic and tetracyclic terpanes identified in the rock extracts,the conventional(C_(20)TT,C_(23)TT,C_(24)TT,C_(24)TeT)and recent(Y1,X1,Z1)were more prominent than all others,indicating mixed input of terrigenous and marine organic *** C_(24)TT/C_(23)TT,C_(24)TeT/(C_(24)TeT+C_(26)TT),C_(19)TT/C_(23)TT,C_(20)TT/C_(23)TT,C_(25)TT/C_(24)TeT,C_(25)TT/C_(26)TT,C_(19)TT/C_(20)TT,C_(24)TeT/C_(26)TT,Z1/(Z1+C_(24)TT),and Y1/(Y1+C_(24)TT)in the rock samples range from 0.33 to 1.30,0.76 to 0.90,0.18 to 0.73,0.34 to 1.05,0.33 to 1.74,0.30 to 1.39,0.31 to0.89,1.66 to 4.33,0.36 to 0.83,and 0.34 to 0.79,*** values further showed that the rock samples were formed from mixed input of terrigenous and marine organic matter and deposited under oxic to suboxic conditions in lacustrine-fluvial/deltaic ***,the C_(24)TeT/C_(20)-26TT,C_(24)TeT/C_(30)HOP,and C_(23)TT/C_(30)HOP ranged from 0.16 to 0.45,0.02 to 0.42,and 0.01 to 0.48,*** range of values suggests that source rocks were within immature to early mature ***,this study showed that tricyclic and tetracyclic terpanes were effective in determining the origin,depositional environments,and thermal maturity of source rocks in the Niger Delta Basin,Nigeria.

关键词： Tricyclic terpanes Tetracyclic terpanes Source rocks Niger delta Gas chromatography-mass spectrometry(GC-MS)

Effect of Varying Aerosol Concentrations and Relative Humidity on Visibility and Particle Size Distribution in Urban Atmosphere

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Journal of Atmospheric Science Research 2021年第3期4卷 14-28页

作者： Ummulkhair Abdulkarim bello tijjani Department of Physics Sa’adatu Rimi College of Education KanoP.M.B.3218Kano StateNigeria Department of Physics Bayero University KanoP.M.B.3011Kano StateNigeria

Atmospheric aerosol concentrations have been found to change constantly due to the influence of source,winds and human activities over short time *** has proved to be a constraint to the study of varied aerosol concentrations in urban atmosphere alongside changing relative humidity and how it affects visibility and aerosol particle size *** this research simulation was carried out using Optical Properties of Aerosols and Clouds(OPAC 4.0)average concentration setup for relative humidity(RH)0-99%at visible wavelength 0.4-0.8μm to vary the concentrations of three aerosol components:WASO(Water-soluble),INSO(Insoluble)and *** Angstrom exponents(α),the curvatures(α2)and atmospheric turbidities(β)were obtained from the regression analysis of Kaufman’s first and second order polynomial equations for *** research determined the mean exponent of the aerosol size growth curve(μ)from the effective hygroscopic growth(geff)and the humidification factors(γ)from visibility enhancement f(RH,λ).The mean exponent of aerosol size distributions(υ)was determined fromμandγ.The results showed that with varied WASO,INSO and SOOT concentrations respectively at different RH,aerosol particle size distributions showed bimodal characteristics with dominance of fine mode *** atmospheric conditions prevailed with increasing turbidity.

关键词： Aerosol concentration Humidification factor Hygroscopic growth Particle size distribution Visibility enhancement

Abattoir as a Tool for Veterinary Extension and Communication Services: A Practical Demonstration of Its Implementation

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Open Journal of Veterinary Medicine 2019年第1期9卷 1-10页

作者： Shehu AbdulQadir Zailani Sani bello Nma Nuhu Abubakar Hassan Kanti Madu Ahmad tijjani Tinau Department of Animal Health Technology Bauchi State College of Agriculture Bauchi State Nigeria Department of Animal Health Niger State Ministry of Livestock and Fisheries Minna Niger State Nigeria Department of Agricultural Extension and Management Bauchi State College of Agriculture Bauchi Nigeria Department of Animal Health and Production Technology Federal College of Horticulture Dadin-Kowa Gombe State Nigeria Department of Animal Health Technology College of Agriculture and Animal Science Kaduna Kaduna State Nigeria

Considering the widespread disease transmission among butchers/meat inspectors and a possible risk of exposure to diseases due to the attitude of some butchers and nature of meat inspector’s jobs. Ignorance and lack of awareness of such dangers has also been identified to be responsible for some of the problems encountered in most instances as well as the presence of some predisposing factors for diseases. In view of the above, this model is developed as a means of demonstrating the use of the abattoir and other registered related slaughter premises in the provision of the physical facility, where the primary role of extension personnel to develop the capacity and capability of target groups in the abattoir and livestock producing community, in order to enhance animal/zoonotic disease surveillance and control. The model if adopted and fully utilized will create awareness among target groups of dangers of disease transmission and ways of curtailing such problems, government through their agencies, professionals and private organizations should be involved in the implementation of this model in order to achieve the desired response.

关键词： Abattoir Extension Disease Transmission

Use of Laryngeal Mask Airway in the Management of a Difficult Airway: A Case Report

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Open Journal of Anesthesiology 2013年第2期3卷 97-101页

作者： Elizabeth Ogboli-Nwasor Ahmad tijjani Lawal Department of Anaesthesia Ahmadu Bello University (ABU) Teaching Hospital Zaria Nigeria Department of Surgery Ahmadu Bello University (ABU) Teaching Hospital Zaria Nigeria

Background: Difficulty in management of the airway occurs most frequently in patients who have Mallampati grade III and IV, and other unfavourable airway findings like short neck, restriction in range of motion of the temporoman-dibular joints and inadequate neck flexion and extension. Because of unavailability of fibreoptic bronchoscopes or inexperience in their use, laryngeal mask airway (LMA) has become a common and acceptable airway management option. This is a case report of a postmenopausal woman who had her airway managed with LMA following initial failed intubation necessitating a rescheduling of the operation. Result: The patient had a successful surgery and postoperative recovery was uneventful. Conclusion: The LMA is a useful option in the management of an anticipated or unexpected difficult airway, especially in resource-poor settings where fibreoptic bronchoscopes may not be readily available.

关键词： Laryngeal Mask Airway Anticipated Difficult Airway