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International Journal of Minerals,Metallurgy and Materials 2014年第1期21卷 1-11页

作者： Yotamu stephen Rainford Hara Institute for Materials Research(IMR) School of ProcessEnvironmental and Materials Engineering(SPEME)University of Leeds

Mineral sulphide （MS）-lime （CaO） ion exchange reactions （MS ＋ CaO = MO ＋ CaS） and the effect of CaO/C mole ratio during carbothermic reduction （MS ＋ CaO ＋ C = M ＋ CaS ＋ CO（g）） were investigated for complex froth flotation mineral sulphide concentrates. Phases in the partially and fully reacted samples were characterised by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The primary phases during mineral sulphide-lime ion exchange reactions are Fe304, CaSO4 Cu2S, and CaS. A complex liquid phase of Ca2CuFeO3S forms during mineral sulphide-lime exchange reactions above 1173 K. The formation mechanisms of Ca2CuFeO3S liquid phase are determined by characterising the partially reacted samples. The reduction rate and extent of mineral sulphides in the presence of CaO and C increase with the increase in CaO/C ratio. The metallic phases are surrounded by the CaS rich phase at CaO/C 〉 1, but the metallic phases and CaS are found as separate phases at CaO/C 〈 1. Experimental results show that the stoichiometric ratio of carbon should be slightly higher than that of CaO. The reactions between CaO and gangue minerals （SiO2 and A1203） are only observed at CaO/C 〉 1 and the reacted samples are excessively sintered.

关键词： sulphide minerals ion exchange carbothermic reduction lime

An incidental presentation of Herlyn-Werner-Wunderlich syndrome with secondary infertility:A case report

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Asian pacific Journal of Reproduction 2022年第5期11卷 243-246页

作者： Abiola Omobonike Adekoya adeniyi Kazeem Akiseku Ayodeji Anike Olatunji Mojisola Adejoke Olusola-Bello Department of Radiology Olabisi Onabanjo University Teaching HospitalSagamuNigeria Department of Obstetrics and Gynecology Olabisi Onabanjo University Teaching HospitalSagamuNigeria

Rationale:Herlyn-Werner-Wunderlich syndrome,also known as obstructed hemi-vagina with ipsilateral renal agenesis(OHVIRA)syndrome,is a rare congenital anomaly of the Müllerian and Wolffian *** is often asymptomatic until puberty and is usually misdiagnosed as *** concerns:A 39-year-old woman desirous of pregnancy was referred to our radiodiagnosis unit for imaging evaluation on account of secondary ***:Incidental discovery of uterine bicornis bicollis and blind-ending hemivagina was noted at ***:This necessitated the search for other genitourinary tract anomalies,and ipsilateral renal agenesis was also ***:A diagnosis of Herlyn-Werner-Wunderlich syndrome was ***:Magnetic resonance imaging(MRI)is considered the gold standard imaging modality for the assessment of uterine ***,in resource-poor centers where MRI is unavailable,a heightened clinical suspicion with the combination of available imaging modalities is important and reliable in making an accurate diagnosis,hence,successful management.

关键词： Infertility Obstructed hemivagina Renal agenesis Uterus didelphys Herlyn-Werner-Wunderlich syndrome

A new hadron spectroscopy

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Frontiers of physics 2015年第2期10卷 1-34页

作者： stephen Lars Olsen Center for Underground Physics Institute of Basic Science Daejeon 305-811 Korea

QCD-motivated models for hadrons predict an assortment of ＂exotic＂ hadrons that have structures that are more complex than the quark-antiquark mesons and three-quark baryons of the original quark-parton model. These include pentaquark baryons： the six-quark H-dibaryon~ and tetraquark, hybrid and glueball mesons. Despite extensive experimental searches, no unambiguous candidates for any of these exotic configurations have been identified. On the other hand, a number of meson states, one that seems to be a proton-antiproton bound state, and others that contain either charmed- anticharmed quark pairs or bottom-antibottom quark pairs, have been recently discovered that neither fit into the quark-antiquark meson picture nor match the expected properties of the QCD- inspired exotics. Here I briefly review results from a recent search for the H-dibaryon, and discuss some properties of the newly discovered states -the proton-antiproton state and the so-called XYZ mesons- and compare them with expectations for conventional quark-antiquark mesons and the predicted QCD-exotic states.

关键词： quarks charmonium pentaquarks di-baryons baryonium tetraquarks

Labechia carbonaria Smith 1932 in the Early Carboniferous of England;affinity,palaeogeographic position and implications for the geological history of stromatoporoid-type sponges

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Journal of Palaeogeography 2021年第1期10卷 1-18页

作者： stephen Kershaw Consuelo Sendino Department of Life Sciences Brunel University LondonKingston LaneUxbridge UB83PHUK Department of Earth Sciences Natural History MuseumCromwell RoadLondon SW75BDUK

Stromatoporoid sponges were very abundant during the middle Palaeozoic Era and are thought to disappear at the end of the Devonian Period in the Hangenberg Crisis. However, there are records of organisms with stromatoporoid-type structure in Carboniferous strata, the subject of this study. The Viséan fossil Labechia carbonaria Smith 1932 has been discussed previously in literature and its affinity has not been confirmed. In this study, the type material of L. carbonaria collected from the middle part of the Frizington Limestone Formation(previously called Seventh Limestone), Holkerian Substage, stored in the Natural History Museum(London, UK) and British Geological Survey(Keyworth, UK) was re-examined. The Holkerian Substage, in which L. carbonaria was found, lies between ca 335–339 Ma, and the Frizington Limestone Formation ranges from topmost Arundian to upper Holkerian, so middle Frizington Limestone Formation is likely approximately 337 Ma. L. carbonaria comprises thick long pillars connected by thin curved cyst plates consistent with the structure of the stromatoporoid genus Labechia. However, a common opinion is that L. carbonaria fossils may be mistaken for fragments of rugose corals,but there are problems with assigning it to the Rugosa. In vertical section(VS) L. carbonaria could be mistaken for a transverse section(TS) of a Carboniferous rugose coral. However, in TS L. carbonaria shows the rounded cross sections of stromatoporoid pillars. If it was a coral, septal sheets of the VS of a coral should be seen. For a rugose affinity to still apply, a coral structure would have to be composed of free trabeculae, but these are not known after the middle of the Devonian Period;there are no corals of Early Carboniferous age with the structure of ***. Another interpretation, that L. carbonaria is a chaetetid, is discounted because it lacks calicles and is very different in structure from chaetetids. We conclude that L. carbonaria is a stromatoporoid. Becau

关键词： Stromatoporoids Holkerian Viséan Carboniferous Rugosa Labechia carbonaria Labechia conferta

The Physico-Chemical Water Quality of the Obafemi Awolowo University Teaching and Research Farm Lake, O.A.U. Campus, Ile-Ife, Southwest, Nigeria

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Journal of Environmental Protection 2019年第7期10卷 881-899页

作者： Adedeji Idowu Aduwo Israel Funso adeniyi Limnology and Hydrobiology Laboratory Zoology Department Obafemi Awolowo University Ile-Ife Osun State Nigeria

The physico-chemical water quality of the Obafemi Awolowo University Teaching and Research Farm Lake, Ile-Ife, Nigeria, was studied over an annual cycle (September 2006 to August 2007) almost 40 years after its impoundment in 1967. This was with a view to obtaining the then current state of physico-chemical water quality parameters with their variations in time and space as well as using some of the data obtained to evaluate the aging process of the lake for the 40 years of its existence. There was no significant (p > 0.05) horizontal variation (i.e. upstream-dowstream) in the physico-chemical characteristics of the lake whereas, Apparent-color, True color, Turbidity, Total Suspended Solids (TSS), Total Solids (TS) and Total Acidity increased significantly (p < 0.05) from the lake surface towards the bottom of the lake. On the other hand, water pH, Dissolved Oxygen (DO);Dissolved Oxygen Saturation (DO% Sat.) and Biochemical Oxygen Demand (BOD5) decreased significantly (p < 0.05) from the lake surface towards the bottom of the lake. Dissolved Oxygen (DO), Dissolved Oxygen Saturation (DO% Sat.) and Nitrate ion (NO-3) were significantly higher (p < 0.05) in the dry season than in the rainy season while, True colour, pH, Conductivity, Total Hardness, Calcium ion (Ca2+), Magnesium ion (Mg2+), Potassium ion (K+) and Sulphate ion (SO2-4) were significantly higher (p < 0.05) in the rainy season than in the dry season. The lake water could be regarded as shallow, coloured, turbid, less transparent, slightly acidic, soft and well-buffered fresh-waterbodies with evidence of aging (i.e. transforming the lake from an oligotrophic status to a eutrophic waterbody). The results indicated that the lake is suitable for most of its applications with little or no adjustments as the case may be;except probably for drinking purposes where some microbial analysis may be necessary.

关键词： Inundation Oligotrophic Eutrophic Aging Man-Made Spillway

Groundwater--sustainability issues and governance needs

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Episodes 2006年第4期29卷 238-243页

作者： stephen Foster IAH President World Bank GW-MATE Director

This paper provides a global overview of groundwater resource sustainability concerns and corresponding governance （management and protection） requirements, with special emphasis on the developing world and on Asia in particular. It is based on an opening plenary address to the International Association of Hydrogeologists （IAH） 34th Congress on the theme ＇Groundwater-- Present Status ＆ Future Tasks＇, celebrated in Beijing, China in the year of the IAH 50th Anniversary on 9 October 2006.

关键词：地下水资源资源管理可持续发展灌溉农业水供应

Combining solar power with coal-fired power plants,or cofiring natural gas

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Clean Energy 2018年第1期2卷 1-9页

作者： stephen Mills IEA Clean Coal Centre Apsley House176 Upper Richmond RoadLondon SW152SHUK

Coal-fired power operators continue to look for ways to increase the efficiency and extend the working lives of their plants by improving operational flexibility and reducing environmental *** possible options are explored here:combining solar energy with coal-fired power generation,and cofiring natural gas in coal-fired *** techniques show *** on the individual circumstances,both can increase the flexibility of a power plant whilst reducing its *** some cases,plant costs could also be ***,any solar-based system is limited geographically to locations that receive consistently high levels of solar ***,although many coal-fired plants already burn limited amounts of gas alongside their coal feed,for cofiring at a significant level,a reliable,affordable supply of natural gas is *** is not the case *** for each technology,there are niche and mainstream locations where the criteria can be *** need for good solar radiation means that the uptake of coal-solar hybrids will be *** natural gas has wider potential:currently,the largest near-term market appears to be for application to existing coal-fired plants in the ***,where gas is available and affordable,potential markets also exist in some other countries.

关键词： coal-fired power plant coal-solar hybrid power generation solar power cofiring hybrid

Mutagenic Effects of Gamma Radiation on Eight Accessions of Cowpea (Vigna unguiculata [L.] Walp.)

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American Journal of Plant Sciences 2016年第2期7卷 339-351页

作者： Festus Olakunle olasupo Christopher Olumuyiwa Ilori Brian Peter Forster Souleymane Bado Department of Crop Protection and Environmental Biology University of Ibadan Ibadan Nigeria Plant Breeding Section Cocoa Research Institute of Nigeria Ibadan Nigeria Biohybrids International Ltd. Reading UK Plant Breeding and Genetics Laboratory Joint FAO/IAEA Agriculture and Biotechnology Laboratory International Atomic Energy Agency Laboratories Seibersdorf Austria

Mutagenesis is used for creating new genetic variability in cultivar improvement. Optimal mutagenic treatment is required for effective mutation induction in crop species. Therefore, radio-sensitivity of cowpea accessions to gamma irradiation was investigated. Seeds of eight cowpea accessions were irradiated with 60Co gamma radiation doses of 100, 200, 300, 400 and 500 Gy. The seeds were sown in pots to evaluate the treatment effects on seed germination (SG), seedling survival (SS) and growth habits of M1 generation. Data were analyzed using descriptive statistics. Low rates of SG (10% - 45%) were recorded at higher doses (500 - 400 Gy) in Ife Brown (IB) and its derivatives, whereas high SG rates (74% - 94%) were observed in IT90K-284-2 across all treatments. Percentage SS was inversely related to gamma dosage. A wide range of LD50 for SG (329 - 1054 Gy) and SS (149 - 620 Gy) were observed across the cowpea accessions. Low LD50 scores for SG (329 - 516 Gy) and SS (149 - 357 Gy) were observed among cowpea with rough seed coat, whereas cowpea with smooth seed coat recorded higher LD50 for SG (521 and 1054 Gy) and SS (449 and 620 Gy). Seed germination LD50 and SS LD50 were highly correlated with mean coat thickness (0.899 and 0.937) than mean seed weight (0.621 and 0.678). Gamma irradiation of cowpea seed at low dosage (100 Gy) increased the vigor of M1 seedlings with respect to primary leaf area, terminal leaflet area, seedling height and plant height at six weeks. Doses of 200 Gy and above resulted in a progressive reduction in vigor of plant and seed setting of cowpea. Radio-sensitivity varied with cowpea genotype and was associated with seed testa texture, thickness and seed weight. Low gamma irradiation treatment (100 Gy) may be used to enhance seedling vigor, vegetative growth and yield of cowpea at M1 generation.

关键词： Cowpea Mutagenesis Radio-Sensitivity Gamma Irradiation Optimum Mutation Treatment

The Power Allocation Game on A Network:A Paradox

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IEEE/CAA Journal of Automatica Sinica 2018年第4期5卷 771-776页

作者： Yuke Li A.stephen Morse the department of political science yale university ieee the department of electrical engineering yale university

The well-known Braess paradox in congestion games states that adding an additional road to a transportation network may increase the total travel time, and consequently decrease the overall efficiency. This paper presents a paradox in a similar spirit and involves a distributed resource allocation game on networks, namely the power allocation game between countries developed in Li and Morse(2017). The paradox is that by having additional friends may actually decrease a country's total welfare in equilibrium. Conditions for this paradox to occur as well as the price of anarchy results are also derived.

关键词： Friends paradox price of anarchy resource allocation game success survival utility

Prediction of Facial Height, Width, and Ratio from Thumbprints Ridge Count and its Possible Applications

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Journal of Forensic Science and Medicine 2017年第4期3卷 223-228页

作者： Lawan Hassan Adamu Samuel adeniyi Ojo Barnabas Danborno Samuel Sunday Adebisi Magaji Garba Taura Department of Anatomy Faculty of Basic Medical SciencesBayero UniversityKanoKano State Department of Human Anatomy Faculty of MedicineAhmadu Bello University Department of Veterinary Anatomy Faculty of Veterinary MedicineAhmadu Bello UniversityZariaKaduna StateNigeria Department of Anatomy College of MedicineUniversity of BishaSaudi Arabia

The fingerprints and face recognition are two biometric processes that comprise methods for uniquely recognizing humans based on certain number of intrinsic physical or behavioral *** objectives of the study were to predict the facial height(FH),facial width,and ratios from thumbprints ridge count and its possible *** was a cross-sectional study.A total of 457 participants were recruited.A fingerprint live scanner was used to capture the plain *** facial photograph was captured using a digital ***’s correlation analysis was used for the relationship between thumbprint ridge density and facial linear ***‑wise linear multiple regression analysis was used to predict facial distances from thumbprint ridge *** result showed that in males the right ulnar ridge count correlates negatively with lower facial width(LFW),upper facial width/upper FH(UFW/UFH),lower FH/FH(LFH/FH),and positively with UFH and UFW/*** right and left proximal ridge counts correlate with LFW and UFH,*** males,the right ulnar ridge count predicts LFW,UFW/LFW,UFW/UFH,and LFH/*** upper face height I,LFW,height of lower third of the face,UFW/LFW was predicted by right radial ridge ***,height of lower third of the face,and LFH/FH were predicted from left ulnar ridge count whereas left proximal ridge count predicted *** females only,the special upper face height I was predicted by right ulnar ridge *** conclusion,thumbprint ridge counts can be used to predict FH,width,ratios among Hausa *** possible application of fingerprints in facial characterization for used in human biology,paleodemography,and forensic science was demonstrated.

关键词： Facial dimensions facial ratios Hausa ethnic group ridge count