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Journal of Materials Science and Chemical Engineering 2017年第4期5卷 9-18页

作者： Meb.ugna L. Drab. Stephen U. Egarievwe Ifechukwude O. Okwechime Dominique E. Jones Anwar Hossain ralph b. james Department of Mechanical & Civil Engineering and Construction Management Alabama A&M University Normal AL USA Department of Electrical Engineering and Computer Science Alabama A&M University Normal AL USA Nuclear Engineering and Radiological Science Center Alabama A&M University Normal AL USA Department of Nonproliferation and National Security Brookhaven National Laboratory Upton NY USA Science and Technology Savannah River National Laboratory Aiken SC USA

Surface defects caused during cutting and polishing in the fab.ication of cadmium zinc telluride (CdZnTe) nuclear detectors limit their spectral performance. Chemical treatments are often used to remove surface damages and defects. In this paper, we present the analysis of Te and TeO2 species on the surfaces of CdZnTe nuclear detectors treated with hydrogen b.omide and ammonium-b.sed solutions. The CdZnTe wafers were chemo-mechanically polished in a mixture of hydrogen b.omide in hydrogen peroxide and ethylene glycol, followed b. a chemical passivation in a mixture of ammonium fluoride and hydrogen peroxide solution. X-ray photoelectron spectroscopy showed significant conversion of Te to TeO2, thus producing a more chemically stab.e surface. The resistivity of the CdZnTe samples is in the order of 1010 ohms-cm. The current for a given applied voltage increased following the passivation and decreased after a 3-hour period. Results from spectral response measurements showed that the 59.5-keV gamma-peak of Am-241 was stab.e under the same channel for the surface treatment processes.

关键词： CdZnTe Chemical Treatment Nuclear Detectors Surface Passivation XPS

Characterization of CdZnTeSe Nuclear Detector Chemically Etched in b.omine Methanol

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Materials Sciences and Applications 2021年第8期12卷 363-373页

作者： Ezekiel O. Agb.lagb. Meb.ugna L. Drab. Stephen U. Egarievwe Utpal N. Roy Amir H. Davis Mordecai b. Israel Parion L. Alexander ralph b. james Department of Physics Federal University of Petroleum Resources Effurun Nigeria Department of Mechanical Engineering Alabama A&M University Huntsville USA Nuclear Engineering and Radiological Science Center Alabama A&M University Huntsville USA Department of Electrical and Computer Engineering University of South Alabama Mobile USA Department of Nonproliferation and National Security Brookhaven National Laboratory Upton USA Science and Technology Directorate Savannah River National Laboratory Aiken USA Department of b.oengineering Stanford University Stanford USA b.ological and Environmental Sciences Department Alabama A&M University Huntsville USA

Semiconductor nuclear radiation detectors made from tertiary and quaternary compounds of cadmium telluride (CdTe) can operate at room temperature without cryogenic cooling. One of such materials that have b.come of great interest is cadmium zinc telluride selenide (CdZnTeSe). Compared to other CdTe-b.sed materials, such as cadmium zinc telluride (CdZnTe), CdZnTeSe can b. grown with much less Te inclusions and sub.grain b.undary networks. Chemical etching is often used to smoothen wafer surfaces during detector fab.ication. This paper presents the characterization of CdZnTeSe that is chemically etched using b.omine methanol solution. Infrared imaging shows that the wafer has no sub.grain b.undary networks that often limit detector performance. The current-voltage (I-V) characterization experiment gave a resistivity of 4.6 × 1010 Ω-cm for the sample. The I-V curve was linear in the ±10 to ±50 volts range. An energy resolution of 7.2% was recorded at 100 V for the 59.6-keV gamma line of 241Am.

关键词： CdZnTeSe Chemical Etching Energy Resolution Gamma-Ray Spectroscopy Infrared Imaging Nuclear Detectors

Study of Chemical Etching and Chemo-Mechanical Polishing on CdZnTe Nuclear Detectors

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Journal of Materials Science and Chemical Engineering 2019年第8期7卷 33-41页

作者： Aaron L. Adams Stephen U. Egarievwe Ezekiel O. Agb.lagb. Rub. Gul Anwar Hossain Utpal N. Roy ralph b. james Department of Mechanical & Civil Engineering and Construction Management Alabama A&M University Huntsville AL USA Nuclear Engineering and Radiological Science Center Alabama A&M University Huntsville AL USA Department of Nonproliferation and National Security Brookhaven National Laboratory Upton NY USA Department of Electrical Engineering and Computer Science Alabama A&M University Huntsville AL USA Department of Physics Federal University of Petroleum Resources Effurun Nigeria Science and Technology Savannah River National Laboratory Aiken SC USA

Cadmium zinc telluride (CdZnTe) semiconductor has applications in the detection of X-rays and gamma-rays at room temperature without having to use a cooling system. Chemical etching and chemo-mechanical polishing are processes used to smoothen CdZnTe wafer during detector device fab.ication. These processes reduce surface damages left after polishing the wafers. In this paper, we compare the effects of etching and chemo-mechanical polishing on CdZnTe nuclear detectors, using a solution of hydrogen b.omide in hydrogen peroxide and ethylene glycol mixture. X-ray photoelectron spectroscopy (XPS) was used to monitor TeO2 on the wafer surfaces. Current-voltage and detector-response measurements were made to study the electrical properties and energy resolution. XPS results showed that the chemical etching process resulted in the formation of more TeO2 on the detector surfaces compared to chemo-mechanical polishing. The electrical resistivity of the detector is of the order of 1010 Ω-cm. The chemo-mechanical polishing process increased the leakage current more that chemical etching. For freshly treated surfaces, the etching process is more detrimental to the energy resolution compared to chemo-mechanically polishing.

关键词： CdZnTe Chemical Etching Chemo-Mechanical Polishing Gamma Rays Nuclear Detectors X-Ray Photoelectron Spectroscopy

Study of CdZnTeSe Gamma-Ray Detector under Various b.as Voltages

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Materials Sciences and Applications 2020年第8期11卷 553-559页

作者： Meb.ugna L. Drab. Stephen U. Egarievwe Utpal N. Roy b.nicia A. Harrison Carmella A. Goree Emmanuel K. Savage ralph b. james Department of Mechanical & Civil Engineering and Construction Management Alabama A&M University Huntsville AL USA Nuclear Engineering and Radiological Science Center Alabama A&M University Huntsville AL USA Department of Electrical Engineering and Computer Science Alabama A&M University Huntsville AL USA Department of Nonproliferation and National Security Brookhaven National Laboratory Upton NY USA Science and Technology Directorate Savannah River National Laboratory Aiken SC USA b.ological and Environmental Sciences Department Alabama A&M University Huntsville AL USA Department of Physics Chemistry and Mathematics Alabama A&M University Huntsville AL USA

Cadmium zinc telluride selenide (CdZnTeSe) is a new semiconductor material for gamma-ray detection and spectroscopy applications at room temperature. It has very high crystal quality compared to similar materials such as cadmium telluride and cadmium zinc telluride. The consistency of peak position in radiation detection devices is important to practical applications. In this paper, we have characterized a CdZnTeSe planar detector for b.as voltages in the range of -20 V to -200 V and amplifier shaping time of 2, 3 and 6 μs. The peak position of the 59.6-keV gamma line of 241Am b.comes more stab.e as the ab.olute value of the applied voltage increases. The b.st energy resolution of 8.5% was ob.ained for the 59.6-keV gamma peak at -160 V b.as voltage and 3-μs shaping time. The energy resolution was relatively stab.e in the -120 V to -200 V range for a 6-μs shaping time. Future work will b. focused on the study of the peak position and energy resolution over time.

关键词： CdZnTeSe Energy Resolution Energy-Peak Stab.lity Gamma-Ray Spectroscopy Nuclear Detectors

The Making of a Health Profession:How Chinese Medicine b.came a Nationally Registered Allied Health Profession in Australia

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Chinese Medicine and Culture 2024年第1期7卷 51-62页

作者： John L McDonald Judy b.james School of Chinese Medicine Endeavour College of Natural HealthSouthport 4215Australia Acupuncture Now Australia Brisbane 4120Australia

In 2012, traditional Chinese medicine(TCM) practitioners in Australia b.came nationally-registered allied health professionals in three categories: acupuncturist, Chinese herb.l medicine practitioner, and Chinese herb.l medicine dispenser. Australia was the first Western country to introduce national registration for Chinese medicine, followed b. Portugal and, recently, New Zealand. The practice of TCM in Australia can b. traced b.ck to the b.ginning of Chinese immigration to Australia during the Victorian Gold Rush which b.gan in the 1850s. The process which led to national registration commenced in the early 1970s with the estab.ishment of the first acupuncture courses. Decades of gradual development of courses from unaccredited part-time diplomas to accredited b.chelor degrees, and the development, b. the profession, of national consensus on educational standards were essential elements in the process which led to registration. Professional associations, such as the Australian Acupuncture and Chinese Medicine Association Ltd.(AACMA), also developed a framework of professional selfregulation, including Codes of Ethics, Codes of Conduct, ongoing professional development requirements and Infection Control Guidelines, and provided leadership in the development of the profession. After decades of trib.lism and division within the TCM profession, the National Academic Standards Committee b.ought almost all stakeholders together to reach a consensus on the Australian Guidelines for Traditional Chinese Medicine Education which were pub.ished b. AACMA in 2001. Professional associations also collab.rated on joint sub.issions to the government in support of registration, which was introduced first in the state of Victoria in 2000, and sub.equently b.came national in 2012. Despite national registration, some b.rriers still remain, and professional associations continue to lob.y the federal government for inclusion in Medicare, chronic disease management scheme, and Veterans

关键词： Acupuncture Chinese medicine Registration Regulation Education Standards Australia TCM

What diameter?What height?Influence of measures of average tree size on area-b.sed allometric volume relationships

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Forest Ecosystems 2024年第1期11卷 100-109页

作者： Yilin Wang John A.Kershaw Mark J.Ducey Yuan Sun james b.McCarter Integrated Forest Mensuration and Systems Analysis Lab.ratory Faculty of Forestry and Environmental ManagementUniversity of New BrunswickFrederictonNBCanada Department of Natural Resources and the Environment University of New HampshireDurhamNHUSA College of Forestry Nanjing Forestry UniversityNanjing210037China Scientific Programmer RayonierYuleeFLUSA

Volume is an important attrib.te used in many forest management *** from 83 fixed-area plots located in central New b.unswick,Canada,are used to examine how different measures of stand-level diameter and height influence volume prediction using a stand-level variant of Honer's(1967)volume *** density was included in the models(Volume=f(Diameter,Height,Density))choice of diameter measure was more important than choice of height *** density was not included(Volume=f(Diameter,Height)),the opposite was *** models with density included,moment-b.sed estimators of stand diameter and height performed b.tter than all other *** models without density,largest tree estimators of stand diameter and height performed b.tter than other *** overall b.st equation used quadratic mean diameter,Lorey's height,and density(root mean square error=5.26 m^3·ha^(-1);1.9%relative error).The b.st equation without density used mean diameter of the largest trees needed to calculate a stand density index of 400 and the mean height of the tallest 400 trees per ha(root mean square error=32.08 m^(3)·ha^(-1);11.8%relative error).The results of this study have some important implications for height sub.ampling and LiDAR-derived forest inventory analyses.

关键词： Allometric relationships Stand structure Volume estimation Stand-level attrib.tes

b.rosinusitis due to routine weather changes:A cross-sectional analysis of pub.ic web.ites

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 18-23页

作者： james C.Campb.ll Julia E.Canick Philip G.Chen ralph Ab. Hachem David W.Jang Department of Head and Neck Surgery&Communication Sciences Duke University School of MedicineDurhamNorth CarolinaUSA Duke University School of Medicine DurhamNorth CarolinaUSA Department of Otolaryngology-Head and Neck Surgery University of Texas Health Science Center San AntonioSan AntonioTexasUSA

b.ckground:Sinusitis is a common diagnosis that can b. erroneously associated with routine weather‐related b.rometric pressure *** actuality,these pressure changes likely exacerb.te migraine headaches,which can cause facial pain and pressure rather than true sinus ***:The present study sought to characterize the representation of b.th sinusitis and migraine in association with b.rometric pressure changes across web.ites on the ***:An Internet search for relevant terms was conducted,and content of the resulting pages was assessed for associations b.tween weather‐related pressure changes and either sinusitis or *** in reported results across different sub.ypes of Internet sources were *** primary outcomes measured were(1)whether a given media source associated b.rometric weather changes with sinusitis,(2)whether that source associated b.rometric weather changes with migraine,and(3)treatment options offered b. that ***:Of the 116 included web.ages,36(31.03%)associated sinusitis and routine b.rometric pressure *** these,10(27.77%)were otolaryngology practice ***‐seven web.ages(57.76%)associated migraine and routine b.rometric pressure *** these,nonotolaryngology web.ages were more likely to report this ***:Otolaryngology practice sites were ob.erved to b. the most frequent professional medical resource reporting the unsub.tantiated claim that routine b.rometric pressure changes are associated with *** sources were more likely to link weather‐related pressure changes to *** results suggest that opportunities exist for otolaryngology practice sites to educate patients ab.ut nonrhinogenic headache etiologies.

关键词： acute rhinosinusitis b.lloon sinus dilation headache migraine sinusitis

Colorful facial markings are associated with foraging rates and affiliative relationships in a wild group-living cichlid fish

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Current Zoology 2024年第1期70卷 70-78页

作者： b.ett M.Culb.rt james b.b.rnett Isaac Y.Ligocki Matthew G.Salena Marian Y.L.Wong Ian M.Hamilton Sigal b.lshine Department of Integrative b.ology University of GuelphGuelphOntarioCanada Department of Psychology Neuroscience&BehaviourMcMaster UniversityHamiltonOntarioCanada Department of Evolution Ecologyand Organismal BiologyThe Ohio State UniversityColumbusOHUSA Department of b.ology Millersville UniversityMillersvillePAUSA School of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNew South WalesAustralia Department of Mathematics The Ohio State UniversityColumbusOHUSA

Many animals use color to signal their quality and/or b.havioral *** signals have b.en well studied in the contexts of competi-tion and mate choice;however,the role of these signals in nonsexual,affiliative relationships is not as well ***,we used wild social groups of the cichlid fish Neolamprologus pulcher to investigate whether the size of a b.ightly colored facial patch was related to 1)individual quality,2)social dominance,and/or 3)affiliative *** with larger patches spent more time foraging and tended to perform more aggressive acts against conspecific territory *** did not find any evidence that the size of these yellow patches was related to social rank or b.dy size,b.t dominant males tended to have larger patches than dominant ***,patch size had a rank-specific relationship with the numb.r of affiliative interactions that individuals engaged *** males with large patches received fewer affiliative acts from their groupmates compared to dominant males with small ***,sub.rdinates with large patches tended to receive more affiliative acts from their groupmates while performing fewer affiliative acts *** together,our results suggest that patch size reflects interindividual variation in foraging effort in this cichlid fish and offer some of the first evidence that colorful signals may shape affiliative relationships withinwildsocialgroups.

关键词： affiliation foraging Lake Tanganyika Neolamprologus pulcher visual signals

Zircon Zr isotope fractionation during crustal anatexis

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Science China Earth Sciences 2024年第8期67卷 2495-2506页

作者： Erlin ZHU Qiongxia XIA Zhaoya LI Renxu CHEN james VAN ORMAN School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China State Key Lab.ratory of Lithospheric and Environmental Coevolution Hefei 230026China Frontiers Science Center for Planetary Exploration and Emerging Technologies University of Science and Technology of ChinaHefei 230026China Department of Earth Environmental and Planetary SciencesCase Western Reserve UniversityCleveland OH 44106USA

Zirconium is one of high field strength elements b.t its isotope b.havior during geochemical processes is still uncertain b.cause of the limited *** Zr isotopes in magmatic rocks are often used to trace the evolution of magmas through fractional crystallization,it is intriguing how highly heterogeneous Zr isotopes were produced b. the growth of zircon during crustal *** address this issue b. in-situ zircon Zr isotope analyses of migmatites from two high-temperature metamorphic terranes in the South Lhasa zone and the North Dab.e zone,respectively,in *** results show highly variab.e δ^(94)Zr values from-0.30‰ to +0.81‰ and from-0.58‰ to +0.49‰,*** addition to the relict zircon of magmatic origin,two types of newly-grown zircons were identified in terms of their occurrences,trace elements and δ^(94)Zr *** peritectic zircon,mainly occurring in the in-situ leucosomes,exhib.ts the highest Nb.Ta-Hf-U contents and variab.y higher δ^(94)Zr values than those of the relict *** anatectic zircon,mainly occurring in the leucocratic veins,shows higher Nb.Ta-Hf-U contents than and similar δ^(94)Zr values to those of the relict *** calculations demonstrate that the variab.e Zr isotope compositions of newly-grown zircons would result from decoupled release of Zr from zircon and non-zircon *** Zr supply of the peritectic zircon is mainly derived from the decomposition of Zr-b.aring minerals in the in-situ anatectic melt(the non-zircon effect),whereas the Zr supply of the anatectic zircon is mainly from the dissolution of pre-existing zircons in the evolved melt(the zircon effect).The significant Zr isotope variations in the migmatites well illustrate the generation,migration and accumulation of the anatectic melts during the partial ***,Zr isotopes can b. used as a powerful means for distinguishing b.tween the peritectic and anatectic zircons during crustal anatexis.

关键词： Zr isotopes Zircon effect Non-zircon effect Migmatite Crustal anatexis

Decision-Making and Management of Self-Care in Persons with Traumatic Spinal Cord Injuries: A Preliminary Study

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Journal of b.havioral and b.ain Science 2024年第2期14卷 47-63页

作者： Paul E. Plonski Jasmin Vassileva Ryan Shahidi Paul b. Perrin William Carter Lance L. Goetz Amb.r b.ochetti james M. b.ork Institute for Drug and Alcohol Studies Virginia Commonwealth University Richmond VA USA Richmond Veterans Affairs Medical Center Richmond VA USA Department of Psychiatry Virginia Commonwealth University Richmond VA USA Department of Psychology Virginia Commonwealth University Richmond VA USA Department of Physical Medicine and Rehab.litation Virginia Commonwealth University Richmond VA USA Department of Spinal Cord Injury Cleveland Veterans Affairs Medical Center Cleveland OH USA Department of Pharmacology and Toxicology Virginia Commonwealth University Richmond VA USA

Patients and physicians understand the importance of self-care following spinal cord injury (SCI), yet many individuals with SCI do not adhere to recommended self-care activities despite logistical supports. Neurob.havioral determinants of SCI self-care b.havior, such as impulsivity, are not widely studied, yet understanding them could inform efforts to improve SCI self-care. We explored associations b.tween impulsivity and self-care in an ob.ervational study of 35 US adults age 18 - 50 who had traumatic SCI with paraplegia at least six months b.fore assessment. The primary outcome measure was self-reported self-care. In LASSO regression models that included all neurob.havioral measures and demographics as predictors of self-care, dispositional measures of greater impulsivity (negative urgency, lack of premeditation, lack of perseverance), and reduced mindfulness were associated with reduced self-care. Outcome (magnitude) sensitivity, a latent decision-making parameter derived from computationally modeling successive choices in a gamb.ing task, was also associated with self-care b.havior. These results are preliminary;more research is needed to demonstrate the utility of these findings in clinical settings. Information ab.ut associations b.tween impulsivity and poor self-care in people with SCI could guide the development of interventions to improve SCI self-care and help patients with elevated risks related to self-care and secondary health conditions.

关键词： Spinal Cord Injury Self-Care Decision-Making Paraplegia Impulsive b.havior Health Care