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defence Technology（防务技术） 2018年第1期14卷 64-69页

作者： C.U.Atuanya d.i.Ekweghiariri C.m.Obele department of metallurgical and materials Engineering Nnamdi Azikiwe UniversityAwkaAnambra StateNigeria department of Polymer and Textile Engineering Nnamdi Azikiwe UniversityAwkaAnambra StateNigeria

mild steel is commonly used in the construction of Pipeline. The major problem of this Pipeline is corrosion. Effort is make my researchers to combat this problem. in this work Co-deposition of Ni-CoSiO_2 composite coating on mild steel was reported with the view to reduce this problem. The SiO_2 was varies from 5 to 25 wt% in the deposition. The microstructure, hardness values and potentiodynamic polarization in simulated sea water were determined. The results show that XRd pattern of the Ni Co deposited mild steel revealed the presence hard phases of NiO, Co_5Ni, Co_2Ni_3, Ni Co5 while that of Ni-CoSiO_2 deposited mild steel revealed the presence harder phases of NiOSiO_2, CoNi_7Si_2, Co_5Ni_2Si_3. The NiCo-25 SiO_2 deposited sample has smaller particle size than Ni-10 Co coating. Coating thickness of 110.7 mm was obtained for Ni-10 Co coating, while coating thickness of 135.7, 157.7, 165.0 mm were obtained at Ni-10 Co-x SiO_2(x=10, 15, 25 wt%). 99.90% corrosion resistance was achieved at Ni-Co-25 SiO_2. This improvement in corrosion resistance after composites coating could be attributed to the hard and fine structure obtained after coating.

关键词： Co-deposition Corrosion microstructure and coating

Chemically mediated interactions between Grapevine, Aphid, Ladybird, and Ant in the Context of insect Chemical Ecology

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Phyton-international Journal of Experimental Botany 2024年第7期93卷 1523-1542页

作者： Taghreed Alsufyani Noura J.Alotaibi Nour Houda m’sakni mona A.Almalki Eman m.Alghamdi department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia department of Biology College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Chemistry department Faculty of ScienceKing AbdulAziz UniversityP.O.Box 80200Jeddah21589Saudi Arabia

This study simpliﬁes the complex relationship among grapevine plants,aphids,ladybirds,and ants,which is essential for effective pest management and ecological *** study investigated the impact of aphid attacks and the presence of ants and ladybirds on the volatile compounds proﬁle released into the chemosphere of the community consisting of the common vine Vitis vinifera,the aphid Aphis illinoisensis,the ladybird Cocci-nella undecimpunctata-and the ant Tapinoma *** study aims to analyze the volatile compounds emitted by the grapevine and surrounding insects in response to these intricate *** extraction of volatile organic compounds(VOCs)was carried out using closed-loop stripping(CLS)and then analyzed via gas chromatography-mass spectrometry(GC-mS)and principles coordinated analysis(PCA)was *** grapevine was exposed to different types and order of treatments,including non-infested,aphid-infested,aphid-infested with ant,aphid-infested with ladybird,and various combinations of ant and *** the aphid attack,the outcomes uncovered massive alterations in the volatile compound proﬁ*** grapevine displayed distinct emissions of germacrene d,an alcohol,and an alkene compared to non-infested *** characteristic VOC proﬁle was the share of infested grapes in the presence of ants,with benzene derivatives and sesquiterpenes dominating the *** coexistence of ladybirds with ants and aphids resulted in a dif-ferent volatile proﬁle characterized by elevated levels of aldehydes,ketones,α-farnesene,and its hydroxy *** was concluded that the emission of VOCs into the chemosphere of the grapevine communities varied qualitatively and quantitatively depending on the level of the relationship complexity within each community in response to the infestation of grapevines by aphids,the presence of ladybirds as natural predators,and the presence of ant as *** grapevine’s status-dependent compounds

关键词： Aphids Aphis illinoisensis volatile organic compounds chemosphere pest management gas chromatography-mass spectrometry closed-loop stripping

Effect of the mesh Transparency on the Electrical Characteristics of dC Pseudo discharge

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Plasma Science and Technology 2015年第6期17卷 481-487页

作者： m.A.Abd AL-HALim A.ABU-HASHEm d.i.mOUBARAK Physics department Faculty of ScienceBenha University Basic Science department Thebes High Institute of Engineering

A dC pseudo discharge for air has been studied. Air pressure is used in the range between 0.7 Torr and 12 Torr. The breakdown occurs between a plane cathode and a mesh anode at transparencies of 19%, 46%, and 65%. The current-voltage characteristic curves of the discharge, which are measured at different pressures, distances, and mesh transparences, take effect in the region of abnormal glow. The discharge voltage decreases as the air pressure increases, while more voltage is needed to maintain the discharge when either the mesh transparency or the inter- electrode distance is increased. An increment of mesh transparency causes high negative potential behind the mesh due to the high concentration of electrons, which accumulate and collide with neutral atoms. Paschen curves deviate from the expected regular one. The left side of Paschen curves appears at inter-electrode distance of 1 mm, whereas the right side appears at inter-electrode distance of 5 mm. The intermediate region is observed only at 3 mm distance between the two electrodes. For the transparency range used in this work, it is found that the decrement of the breakdown voltage, on the right side, depends on the mesh transparency. For different electrode separations, the measured Paschen curves are coincident and deviate from the standard ones of Paschen＇s law.

关键词： pseudo discharge mesh transparency Paschen curves

Study of Thermal and Hydraulic Performances of Circular and Square Ribbed Rough microchannels Using LBm

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Journal of Thermal Science 2015年第6期24卷 549-556页

作者： m.A.Taher H.d.Kim Y.w Lee department of mechanical and Automotive Engineering Pukyong National University department of mechanical Engineering Andong National University

The effects of roughness geometries and relative roughness height at the slip flow regime to investigate the thermal and hydraulic performances of microchannel have been considered in the present article using a thermal Lattice Boltzmann method(TLBm).A two dimensional 9-bit(d2Q9)single relaxation time(SRT)model is used to simulate this *** micro-flows,the local density variation is still relatively small,but the total density changes,therefore,in order to account this density variation and its effect on the kinematic viscosityν,a new relaxation time proposed by Niu et al.[13]is *** roughness geometry is modeled as a series of square and circular riblets with a relative roughness height from 0%to 10%of the channel *** friction coefficients in terms of Poiseuille number(Pn)and the dimensionless heat transfer rate in terms of Nusselt number(Nu)have been discussed in order to analyze the roughness *** thermal-hydraulic performance(η)is calculated considering the simultaneous effects of thermal and fluid friction(pressure drop)at the slip flow regime at Knudsen number,Kn,ranging from 0.01 to 0.10 with other controlling parameters for both kind of *** results have been compared with previous published works and it is found to be in very good agreement.

关键词： Lattice-Boltzmann Friction factor Knudsen number Surface Roughness

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Occupational diseases and Environmental medicine 2024年第2期12卷 142-159页

作者： Adjobimey mênonli mikponhoué Rose dégbey Cyriaque Hountohotègbé Esdras Guédou Alexandre Lawani Affousath Ayélo Paul Hinson Antoine Unité de Recherche et d&#8217Enseignement en Sant&#233 au Travail et Environnement FSS Cotonou Benin Service de Santé au Travail du Centre National Hospitalier Universitaire de Pneumo-Phtisiologie Cotonou Benin Occupational Health Service at the Referral Hospital Construction Site Abomey-Calavi Benin inter-Faculty Center for Environmental Training and Research for Sustainable development (CiFREd) Abomey-Calavi Benin

introduction: work-related accidents are frequent and serious in the construction sector. The aim of the study was to determine the frequency and factors associated with occupational accidents on the construction site of a referral hospital in Benin. methods: A cross-sectional study was carried out. The sample size was calculated using the Schwartz form adjusted for the number of workers on site and was 129 workers. Random sampling was used. The dependent variable was work-related accidents. The other variables were socio-demographic and occupational characteristics. data were collected through a questionnaire survey. medians and proportions were calculated. An association was sought using Chi-square and Fisher tests with a threshold of p Results: A total of 132 workers were included. Their median age was 30 years with an iTQ of [27 - 38];men were the most represented 126 (95.45%) with a level of education higher than or equal to high school in 101 (76.52%) and in the majority with a permanent status 85 (64.39%). Seniority of more than 5 years was observed in 92 (69.7%). workers working more than 8 hours of overtime per week numbered 57 (43.18%). Exposure to vibrating objects was 49 (37.12%). in terms of psychosocial constraints, 82.58% had high psychological demands;79.53% low decision-making latitude;50.76% low social support. The frequency of work-related accidents was 6.82%, and the only associated factor was the type of worker (p = 0.016). On the other hand, there were 10.2% accidents among workers handling vibrating objects versus 4.98% among those not using them. with regard to psychosocial constraints, the following frequencies were recorded respectively: 6.42% among those with high psychological demand versus 8.7% among those with low psychological demand;7.62% among those with low decision-making latitude versus 3.7% among those with high decision-making latitude;8.96% among those with low social support versus 4.62% among those with high support. Conclusi

关键词： Occupational injury Building and Civil Engineering Construction Environment

Recoil polarimetry in meson photoproduction at mAmi

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Chinese Physics C 2009年第12期33卷 1373-1376页

作者： m.H. Sikora d.i. Glazier d.P. watts University of Edinburgh King’s Buildings Edinburgh EH9 3JZ United Kingdom

The nucleon excitation spectrum remains poorly known, with the masses, widths, Em couplings and even existence of many states not well established. A program of experiments using meson photoproduction off the nucleon is being carried out to improve this situation. A new large acceptance recoil polarimeter has been developed by the Edinburgh group for use in such reactions with the Crystal Ball at mAmi. This work summarizes the procedure used to measure recoil polarization with the new device and presents some preliminary results for the double polarization observable Cx in the reaction γp→pπ, compared to the current partial wave analysis.

关键词： polarimeter meson photoproduction polarization observable recoil

microstructure change in Fe-based metallic glass and nanocrystalline alloy induced by liquid nitrogen treatment

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Journal of materials Science & Technology 2021年第10期69卷 1-6页

作者： m.C.Ri d.w.ding Y.H.Sun w.H.wang institute of Physics Chinese Academy of SciencesBeijing100190China Songshan Lake materials Laboratory Dongguan523808China

The effects of acyclic liquid nitrogen(LN)treatment in a temperature range of-196℃to 50℃on the thermal and magnetic stability of Fe78Si9B13 and Fe73.5Si13.5B9Nb3Cu1 glassy ribbons have been *** intrinsic heterogeneities of the metallic glasses can be activated through cryogenic thermal cycling,making irreversible structural changes after the treatment and inducing rejuvenation to the *** microstructural changes of both Fe-based metallic glass(mG)and nanocrystalline alloy induced by LN treatment were *** experimental results show that the LN treatment could effectively rejuvenate the Fe-Si-B mGs and change their thermomechanical and magnetic *** on the partially-crystallinity and well-known magnetic constants,the increase of the energy at the order of 10m J/g and magnetic domain wall movement and rotation at the order of 5-6μm and 0.5°-0.8°are found for FiNEmET-type amorphous alloy after LN *** is also found that LN treatment can contribute a little stored energy to the magnetic domain wall movement and magnetic domain rotation.

关键词： metallic glasses Cryogenic thermal treatment Soft magnetic materials Rejuvenation Stored energy domain wall

Linear and nonlinear optical analysis on semiorganic-proline cadmium chloride single crystal

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Chinese Physics B 2018年第4期27卷 476-482页

作者： mohd Anis m i Baig S S Hussaini m d Shirsat mohd Shkir H A Ghramh department of Physics Sant Gadge Baba Amravati University Amravati-444602 Maharashtra India Ram meghe College of Engineering and management Amravati-444701 Maharashtra India Crystal Growth Laboratory Department of Physics Milliya Arts Science and Management Science College Beed431122 Maharashtra India RUSA Center for Advanced Sensor Technology Department of Physics Dr. Babasaheb-Ambedkar-Marathwada University A urangabad-431005 Maharashtra India Research Center for Advanced materials Science (RCAmS) King Khalid University P. O. Box 9004 Abha-61413 Saudi Arabia Advanced Functional materials & Optoelectronic Laboratory (AFmOL) Department of Physics College of Science King Khalid University P. O. Box 9004 Ahha-61413 Saudi Arabia

in the current investigation,L-proline cadmium chloride monohydrate（LPCC） single crystal is grown by a slow solvent evaporation technique to identify its credibility for nonlinear optical device *** constituent elements of LPCC crystal are determined by the energy dispersive spectroscopic（EdS） *** single crystal x-ray diffraction technique is used to determine the structural dimensions of LPCC *** UV-visible studies are carried out within a wavelength range of 200 nm–1100 nm to determine the optical transmittance of LPCC *** linear optical parameters of LPCC crystal are evaluated using the transmittance data to discuss its importance for distinct optical *** Nd：YAG laser assisted Kurtz–Perry test is carried out to determine the enhancement in second harmonic generation efficiency of LPCC crystal with reference to KdP *** Z-scan technique is employed to assess the third order nonlinear optical（TONLO） properties of LPCC crystal at 632.8 *** Z-scan data are utilized to evaluate the TONLO refraction,absorption and susceptibility of LPCC *** color oriented luminescence behavior of LPCC crystal is investigated within a spectral range of 350 nm–700 *** dependence of dielectric constant and dielectric loss on temperature and frequency is evaluated through the dielectric measurement studies.

关键词： crystal growth dielectric studies nonlinear optical materials optical studies

Recovery rates of persistent post-COVid-19 olfactory dysfunction using psychophysical assessment:A longitudinal cohort study

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world Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 79-87页

作者： Jeremy P.Tervo Patricia T.Jacobson Brandon J.Vilarello Tiana m.Saak Francesco F.Caruana Liam w.Gallagher Joseph B.Gary david A.Gudis Paule V.Joseph d.P.devanand Terry E.Goldberg Jonathan B.Overdevest Columbia University Vagelos College of Physicians and Surgeons New YorkNew YorkUSA department of Otolaryngology-Head and Neck Surgery New York-Presbyterian/Columbia University Irving Medical CenterNew YorkNew YorkUSA department of Otolaryngology-Head and Neck Surgery University of PittsburghPittsburghPennsylvaniaUSA department of Otolaryngology-Head and Neck Surgery University of MinnesotaMinneapolisMinnesotaUSA National institute of Alcohol Abuse and Alcoholism Section of Sensory Science and Metabolism&National Institute of Nursing ResearchBethesdaMarylandUSA New York-Presbyterian/Columbia University irving medical Center New YorkNew YorkUSA

Objectives:Persistent olfactory dysfunction(Od)following loss of smell associated with SARS-CoV-2 infection is a major feature of long *** on the prevalence of persistent Od predominantly rely on self-reported olfactory *** studies have tracked longitudinal rates of recovery using psychophysical assessment among patients presenting for evaluation of persistent Od beyond a window of acute *** anchored in standardized testing methods are needed to counsel patients who fail to acutely regain their sense of *** study aims to quantify the degree of persistent Od in post-COVid-19 patients who experience subjective and psychophysical ***:we grouped participants presenting for Od evaluation into cohorts based on both subjective and psychophysical olfactory status at a baseline assessment and assessed their olfactory abilities with a visual analogue scale and the Sniffin'Sticks extended test at baseline and 1-year time *** had confirmed a history of COVid-19 by lab evaluation or clinical diagnosis if lab evaluation was not ***:Baseline olfactory evaluation was completed by 122 participants,53 of whom completed the 1-year follow-up *** participants presenting with perceived Od,74.5%had confirmed psychophysical Od at baseline,with 55.1%at 1-year *** had reliable trends in self-rated versus psychophysically tested olfactory function at both time *** total threshold,discrimination,and identification(Tdi)score improved by+3.25 points in the cohort with psychophysical Od(p=0.0005),with this improvement largely attributable to an increase in median threshold scores(+2.75 points;p=0.0004).Conclusions:Od persists in a significant number of patients who fail to acutely recovery their sense of smell after COVid-19,with many demonstrating lingering deficits at *** in threshold,but not discrimination or identification,most significantly mediate improvement

关键词： long COVid olfaction post-COVid condition smell dysfunction

Effect of synthesis conditions and surrounding medium on luminescence properties of YVO_4:Eu^(3+) nanopowders

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Journal of Rare Earths 2015年第2期33卷 129-134页

作者： E.V.Golyeva d.V.Tolstikova i.E.Kolesnikov m.d.mikhailov St.Petersburg State Polytechnical University St.Petersburg 195251 Russia Scientific and Technological institute of Optical material Science VNTs S.I.Vavilov State Optical InstituteSt.Petersburg 192171 Russia St.Petersburg State University St.Petersburg 199034 Russia

Nanocrystalline yttrium vanadate doped with europium ions powders were synthesized via sol-gel method based on decomposition of metal-polymer complex. X-ray diffraction analysis showed that samples had pure tetragonal phase without any impurities. Scanning electron microscopy and static light scattering technique were used to study morphology and size of prepared nanoparticles. Average diameter of the nanoparticles was about 40 nm. The changes in structural and luminescence properties were observed as a function of the first and second calcination temperature. The optimal conditions for synthesis of nanoparticles were determined as Т1=500℃, t1=1 h; Т2=950 ℃, t2=1.5 h. The effect of different media surrounding the nanoparticles on their luminescence properties and lifetime was investigated and discussed in terms of effective refractive index. it was found that the observed lifetime of YVO4：Eu^3＋ 5 at.% nanophosphor was decreased from 0.64 ms in air（nmed=1） to 0.45 ms in chalcogenide glass As39S61（nmed=2.39）.

关键词： nanopowders rare earths luminescence effective refractive index lifetime