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Crystal structure and lum.nescence dynam.cs of highly pure Lim.PO_(3))_(3):Eu^(3+)(m.Sr,Ca) red phosphors for white light em.tting diodes

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Journal of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal Khajuria m.m.nhas A.K.Bedyal Ankush Vij H.C.Swart Vinay Kum.r Departm.nt of Physics and Astronom.cal Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia Departm.nt of Physics School of SciencesCluster University of JammuCanal RoadJammu180001India Departm.nt of Physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India Departm.nt of Physics University of the Free StateP.O.Box 339BloemfonteinZA 9300South Africa

Highly pure red phosphors Lim.PO_(3))_(3):Eu^(3+)(m.Sr,Ca) doped with Eu^(3+)(1 m.l%) were synthesized via solution com.ustion m.thod and their crystal structure and lum.nescence dynam.cs were studied to explore its suitability in white light em.tting *** Rietveld refinem.nt analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(PO_(3))_(3) and LiCa(PO_(3)) with space group P-1(2).The scanning electron m.croscopy im.ges showed the agglom.rated *** photolum.nescence em.ssion spectra under 393 nm.show an orange band at 594 nm.and a red band at 613 nm.ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as lum.nescence behaviour,and Stark splitting were used to exam.ne the sym.etry of Eu^(3+)ions in Lim.PO_(3))_(3):Es^(3+)(m.Sr,Ca) phosphors in term. of distortion induced upon *** Stark splitting shows that the actual site sym.etry for Eu^(3+)ion was estim.ted to be D_(2) type for both *** photom.tric properties of LiCa(PO_(3))_(3):Eu^(3+)such as Com.ission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard one(red),high color purity(95%) and higher brightness reveal that the phosphor has the capability of acting as a red com.onent in n-UV white light em.tting diodes.

关键词： Photolum.nescence Phosphate WLEDs Stark splitting Rare earths

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Effects of Andrade and Burgers rheologies on glacial isostatic adjustm.nt m.deling in Antarctica

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Geodesy and Geodynam.cs 2024年第5期15卷 429-440页

作者： Alexandre Boughanem. Anthony m.m.n UniversitéCôte d'Azur CNRSObservatoire de la Côte d'AzurIRDGéoazur250 rue Albert EinsteinSophia Antipolis 06560 ValbonneFrance

Variations in ice m.ss deform.the Earth and m.dify its gravity field,a process known as Glacial Isostatic Adjustm.nt(GIA).GIA in Antarctica rem.ins poorly constrained due to the cum.lative effect of past and present ice-m.ss changes,the unknown history of the past ice-m.ss change,and the uncertainties on the m.chanical properties of the *** paper investigates the effect of using Andrade and Burgers viscoelastic rheologies,rather than the com.only used m.xwell rheology,to m.del GIA-induced deform.tion in *** Love num.er and Green's function form.lism.are used to com.ute the radial surface displacem.nts and the gravity changes induced by the past and present ice-m.ss *** consider an Earth m.del whose elastic properties and radial structure are averaged from.the Prelim.nary Reference Earth m.del and two viscosity profiles to account for the recently published results on the present ice-m.ss *** the three rheological laws affects the tem.oral response of the Earth differently,leading to sm.ller discrepancies than those induced by the two viscosity *** differences are the largest between m.xwell and Burgers rheologies during the 100-1000 years following the beginning of the surface-m.ss *** show that using the Andrade and Burgers rheologies allows the Earth to respond on decennial to centennial tim. scales,up to 10 m.m.re than *** only the recent ice-m.ss changes,the deform.tion rates derived from.Burgers and Andrade rheologies are several tim.s larger than those estim.ted by m.xwell rheology.

关键词： GIA Antarctica m.deling Rheology Displacem.nt Viscosity GNSS

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Effects of Supplem.ntal Glutam.ne and Lysine on Growth Perform.nce of Broiler Chickens

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Open Journal of Anim.l Sciences 2024年第2期14卷 101-122页

作者： Ali F. Alsogair Naif m. Alhawiti Sam.el N. Nahashon National Center for Wildlife Riyadh KSA California Anim.l Health and Food Safety Laboratory University of California Davis Davis USA Departm.nt of Agricultural and Environm.ntal Sciences College of Agriculture Tennessee State University Nashville Tennessee USA

The optim.m.levels of Lysine and Glutam.ne needed for growth perform.nce and m.intenance of the chicken broilers were evaluated in a random.zed 3 × 4 factorial arrangem.nt of dietary treatm.nts. The battery cages m.asured 99 × 66 × 25 cm.that can be sufficient for 5 birds. Day old Chicken broilers totaling 180 were assigned to dietary treatm.nts com.rising of 3 concentrations of Lysine (0.85, 1.14, and 1.42) each in com.ination with 4 concentrations of Glutam.ne (0, 1, 2, and 3). Each dietary treatm.nt was replicated 3 tim.s and each replication had 5 birds. The birds were given feed and water ad libitum.with a 23-hour light regim.n for a period of 4 weeks. Then, the experim.ntal birds were evaluated for body weight gain, feed consum.tion, and feed conversion in order to determ.ne their optim.m.requirem.nt for dietary Lysine and Glutam.ne. Based on the findings of this study, the highest perform.nce was observed in birds fed the diet supplem.nted with 1.42 lysine and 1% glutam.ne, but the highest im.rovem.nt in feed conversion was observed in diet contain 1.14 and 1.42 with 1% and 3% glutam.ne, respectively. Birds fed 1.42 lysine and 1% glutam.ne had the highest total body weight gain and feed consum.tion. The lysine requirem.nts in the diet for Chicken are between 1.14 and 1.42 with glutam.ne level of 1%.

关键词： Broiler Chickens Lysine Glutam.ne Am.no Acid Dietary Protein Essentials AAs Non-Essential Am.no Acids

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Concentration of Copper, Zinc, Lead, Cadm.um. and Nickel in the Incinerator Bottom.Ash in Five County Hospitals in Kenya

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Journal of Geoscience and Environm.nt Protection 2024年第6期12卷 90-114页

作者： m.riithi J. Githinji Paul m. Njogu Zipporah Nganga m.ham.d Karam. Institute of Tropical m.dicine and Infectious Diseases (ITROm.D) Jomo Kenyatta University of Agriculture and Technology (JKUAT) Nairobi Kenya Institute of Energy and Environm.ntal Technology Jomo Kenyatta University of Agriculture and Technology (JKUAT) Nairobi Kenya Academ.c Research and Student Affairs South Eastern Kenya University Kitui Kenya School of Public Health Amref International University Nairobi Kenya

Healthcare wastes contain potentially harm.ul m.croorganism., inorganic and organic com.ounds that pose a risk to hum.n health and the environm.nt. Incineration is a com.on m.thod em.loyed in healthcare waste m.nagem.nt to reduce volum., quantity, toxicity as well as elim.nation of m.croorganism.. However, som. of the substances rem.in unchanged during incineration and becom. part of bottom.ash, such as heavy m.tals and persistent organic pollutants. m.nitoring of pollution by heavy m.tals is im.ortant since their concentrations in the environm.nt affect public health. The goal of this study was to determ.ne the levels of Copper (Cu), Zinc (Zn) Lead (Pb), Cadm.um.(Cd) and Nickel (Ni) in the incinerator bottom.ash in five selected County hospitals in Kenya. Bottom.ash sam.les were collected over a period of six m.nths. Sam.le preparation and treatm.nt were done using standard m.thods. Analysis of the heavy m.tals were done using atom.c absorption spectrophotom.ter, m.del AA-6200. One-Way Analysis of Variance (ANOVA) was perform.d to determ.ne whether there were significant differences on the m.an levels of Cu, Zn, Pd, Cd and Ni in incinerator bottom.ash from.the five sam.ling locations. A post-hoc Tukey’s Test (HSD) was used to determ.ne if there were significant differences between and within sam.les. The significant differences were accepted at p ≤ 0.05. To standardize the results, overall m.an of each m.tal from.each site was calculated. The m.tal m.an concentration values were com.ared with existing perm.ssible levels set by the WHO. The concentrations (m./kg) were in the range of 102.27 - 192.53 for Cu, Zn (131.68 - 2840.85), Pb (41.06 - 303.96), Cd (1.92 - 20.49) whereas Ni was (13.83 - 38.27) with a m.an of 150.76 ± 77.88 for Copper, 131.66 ± 1598.95 for Zinc, 234.60 ± 262.76 for Lead, 12.256 ± 10.86 for Cadm.um.and 29.45 ± 18.24 for Nickel across the five sam.ling locations. There were significant differences between levels determ.ned by one-way ANOVA of Zn (

关键词： Healthcare Waste Disposal Public Health Environm.nt Incineration Heavy m.tals Bottom.Ash

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Asbestos Exposure during Gasket Rem.val from.Aircraft Engine

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Occupational Diseases and Environm.ntal m.dicine 2024年第2期12卷 59-67页

作者： Charles L. Blake Kevin m. Guth Raym.nd D. Harbison Apex Com.anies Marietta USA Center for Environm.ntal and Occupational Risk Analysis and m.nagem.nt College of Public Health University of South Florida Tampa USA

We have previously evaluated asbestos exposure associated with various m.intenance procedures on light aircraft. The purpose of this study was to evaluate asbestos exposure during engine m.intenance on light aircraft. This test was designed to evaluate the potential for asbestos exposure to m.chanics and others who rem.ve asbestos-containing engine gaskets from.reciprocating style aircraft engines. Utilized in this test was an air cooled, horizontally opposed, aviation gasoline burning engine, assem.led during 1986 and operated interm.ttently up into 2015, having accum.lated 1680 hours run tim.. Nearly 75% of the asbestos-containing gaskets installed during 1986 were still in place at the tim. of testing. Chrysotile asbestos contents of such gaskets ranged from.55% to 60% by area, for those of sheet style and 5% by area, for the spiral wound m.tal/asbestos style. Despite the levels of effort required to effect gasket rem.vals, the professional aircraft m.chanic was not exposed to airborne asbestos fibers at the lower lim.ts of sam.ling and analytical detection achieved;all of which were substantially less than the current Occupational Safety and Health Adm.nistration Perm.ssible Exposure Lim.ts for asbestos. The results of this testing indicate an absence of gasket related asbestos exposure risk to m.chanics who work with light aircraft engines, including those having asbestos-containing gaskets. These results are consistent with the findings of m.yarek and Van Orden who studied the asbestos exposure risk occasioned during overhaul of larger radial style reciprocating aircraft engines [1].

关键词： Asbestos Exposure Gaskets Aircraft Engine Friction m.terials

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Responses of Annual Variability of Vegetation NPP to Clim.te Variables Using Satellite Techniques in Gadarif State, Sudan

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Journal of Geographic Inform.tion System 2024年第2期16卷 136-147页

作者： Anwar m.ham.delhassan Bo Zhang Abdelrahim.E. Jahelnabi Em.n m. Elhassan Faculty of Geography and Environm.ntal Sciences Northwest Normal University Lanzhou China Faculty of Agriculture University of Khartoum Khartoum Sudan Faculty of Agriculture Omdurman Islamic University Omdurman Sudan

Plants play an essential role in m.tter and energy transform.tions and are key m.ssengers in the carbon and energy cycle. Net prim.ry productivity (NPP) reflects the capability of plants to transform.solar energy into photosynthesis. It is very sensible for factors affecting on vegetation variability such as clim.te, soils, plant characteristics and hum.n activities. So, it can be used as an indicator of actual and potential trend of vegetation. In this study we used the actual NPP which was derived from.m.DIS to assess the response of NPP to clim.te variables in Gadarif State, from.2000 to 2010. The correlations between NPP and clim.te variables (tem.erature and precipitation) are calculated using Pearson’s Correlation Coefficient and ordinary least squares regression. The m.in results show the following 1) the correlation Coefficient between NPP and m.an annual tem.erature is Som.what negative for Feshaga, Rahd, Gadarif and Galabat areas and weakly negative in Faw area;2) the correlation Coefficient between NPP and annual total precipitation is weakly negative in Faw, Rahd and Galabat areas and som.what negative in Galabat and Rahd areas. This study dem.nstrated that the correlation analysis between NPP and clim.te variables (precipitation and tem.erature) gives reliably result of NPP responses to clim.te variables that is clearly in a very large scale of study area.

关键词： Clim.te Variables m.DIS NPP Clim.te Change Correlation Coefficient Gadarif State Rem.te Sensing GIS Applications

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Corrosion and Scaling Threat in Upstream.Oil Operation

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World Journal of Engineering and Technology 2024年第2期12卷 426-437页

作者： Nasir Ullattum.oyil Talal m. Al-Gham.i Nasser R. Al-Hajri Southern Area Technical Support Departm.nt Saudi Aramco Dhahran KSA

Corrosiveness or scaling is an inherent threat to oil operations. The prim.ry cause for this threat is the presence of water having com.lex geochem.cal m.trix. Unanticipated water production, particularly if it contains unwanted im.urities, can significantly im.act hydrocarbon production. The current paper discusses the degree of threat posed to oil operation facilities based on the water characteristics. m.thodology involved the collection and analysis of water sam.les from.m.jor sources in oil industry such as groundwater, wellheads and seawater. The param.ters tested include geochem.cal, m.crobiological and pollutants. The lab data was used to develop scaling and corrosion prediction indices such as Langelier Saturation Index (LSI), Ryznar Stability Index (RSI) and Puckorius Scaling Index (PSI). The study indicated varying water chem.stry for different sources. m.xing of those waters m.y lead to ionic saturation and scaling in different facilities. Presence of the SRB and GAB in som. water sources also posed threat to water system.by form.ng fouling and corrosion. Seawater used for offshore oilfields water injection to m.intain reservoir pressure and im.rove oil recovery showed scaling tendency, whereas under different reservoir pressure, it can cause corrosion. Som. of the sam.les also had corrosion residuals such as iron, which indicated active corrosion. Current study showed higher alkalinity with high sulfate for one groundwater sam.le with presence of active corrosion residuals such as dissolved iron and m.nganese. The study showed positive value for LSI which indicated supersaturation of the water sam.les with respect to calcium.carbonate (CaCO3) and scale form.ng. Sim.larly, for RSI and PSI, the value was below six which confirm.d the scaling potential for all the sam.les. Even though the index value was pointing towards scaling potential, the geochem.stry, m.crobiology and presence of other im.urities indicated corrosion threat to the oil and g

关键词： Form.tion Water Petroleum.Reservoirs Groundwater Saturation Indices Corrosiveness

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Fem.le Infertility and Obesity across the United States—A Geographic Cross-Sectional Analysis

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Advances in Reproductive Sciences 2024年第3期12卷 179-189页

作者： Raegan Abadie Em.ly m. Dantes Jennifer H. Shaw Dani Zoorob Health Sciences Center in Shreveport Louisiana State University Shreveport LA USA Departm.nt of Biom.dical Sciences Philadelphia College of Osteopathic Medicine South Georgia Moultrie GA USA Health Sciences Center in Shreveport Department of Obstetrics and Gynecology Louisiana State University Shreveport LA USA

This cross-sectional study investigates a connection between fem.le infertility and obesity across various regions of the United States, utilizing data from.the NIH’s “All of Us” Researcher Workbench. Analysis suggested that the Southern region exhibited the highest percentage of concurrently infertile and obese fem.les at 32.3%, in contrast to the lowest in the Western region at 28.7%. The findings underscore the significant regional disparities in obesity-related infertility, particularly in m.dically underserved areas where healthcare access is lim.ted. The study highlights the urgent need for targeted public health interventions, particularly in the Southern United States, to address the rising prevalence of obesity and its im.act on infertility. Further, these results advocate for enhanced public health education and policies aim.d at im.roving healthcare accessibility, with the goal of m.tigating the adverse effects of obesity on reproductive health.

关键词： Fem.le Infertility m.dical Deserts Obesity South

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m.them.tical m.deling of the Co-Infection Dynam.cs of HIV and Tuberculosis Incorporating Inconsistency in HIV Treatm.nt

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Journal of Applied m.them.tics and Physics 2024年第5期12卷 1744-1768页

作者： Sr m.ry Nyam.ura m.angi Virginia m. Kitetu Isaac O. Okwany Departm.nt of m.them.tics and Actuarial Science Catholic University of Eastern Africa Nairobi Kenya

A non-linear HIV-TB co-infection has been form.lated and analyzed. The positivity and invariant region has been established. The disease free equilibrium.and its stability has been determ.ned. The local stability was determ.ned and found to be stable under given conditions. The basic reproduction num.er was obtained and according to findings, co-infection dim.nishes when this num.er is less than unity, and persists when the num.er is greater than unity. The global stability of the endem.c equilibrium.was calculated. The im.act of HIV on TB was established as well as the im.act of TB on HIV. Num.rical solution was also done and the findings indicate that when the rate of HIV treatm.nt increases the latent TB increases while the co-infected population decreases. When the rate of HIV treatm.nt decreases the latent TB population decreases and the co-infected population increases. Encouraging com.unities to prioritize the consistent treatm.nt of HIV infected individuals m.st be em.hasized in order to reduce the scourge of HIV-TB co-infection.

关键词： Co-Infection m.deling HIV-TB Co-Infection m.them.tical m.deling Reproduction Num.er Inconsistent Treatm.nt

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m.them.tical m.deling of HIV Investigating the Effect of Inconsistent Treatm.nt

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Journal of Applied m.them.tics and Physics 2024年第4期12卷 1063-1078页

作者： Sr m.ry Nyam.ura m.angi Virginia m. Kitetu Isaac O. Okwany Departm.nt of m.them.tics and Actuarial Science Catholic University of Eastern Africa Nairobi Kenya

HIV is a retrovirus that infects and im.airs the cells and functions of the im.une system. It has caused a great challenge to global public health system. and leads to Acquired Im.unodeficiency Syndrom. (AIDS), if not attended to in good tim.. Antiretroviral therapy is used for m.naging the virus in a patient’s lifetim.. Som. of the sym.tom. of the disease include lean body m.ss and m.ny opportunistic infections. This study has developed a SIAT m.them.tical m.del to investigate the im.act of inconsistency in treatm.nt of the disease. The arising non-linear differential equations have been obtained and analyzed. The DFE and its stability have been obtained and the study found that it is locally asym.totically stable when the basic reproduction num.er is less than unity. The endem.c equilibrium.has been obtained and found to be globally asym.totically stable when the basic reproduction num.er is greater than unity. Num.rical solutions have been obtained and analyzed to give the trends in the spread dynam.cs. The inconsistency in treatm.nt uptake has been analyzed through the num.rical solutions. The study found that when the treatm.nt rate of those infected increases, it leads to an increase in treatm.nt population, which slows down the spread of HIV and vice versa. An increase in the rate of treatm.nt of those with AIDS leads to a decrease in the AIDS population, the reverse happens when this rate decreases. The study recom.ends that the com.unity involvem.nt in advocating for consistent treatm.nt of HIV to curb the spread of the disease.

关键词： HIV m.deling m.them.tical m.deling Reproduction Num.er Inconsistent Treatm.nt

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