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International Journal of Otolaryngology and Head & Neck Surgery 2024年第1期13卷 1-10页

作者： Fatiou Alabi Bouraïma Cocouvi Bruno Ametonou Ulrich Bidossèssi Vodouhe François Avakoudjo Jorelle Wafo Marius Claude Flatin spéro H. R. Hounkpatin Wassi Adjibabi Faculty of Medicine University of Parakou Parakou Benin Faculty of Health Sciences University of Abomey-Calavi Cotonou Benin

Introduction: Noise is the second leading cause of hearing loss in adults after presbycusis. The objective of this work was to study hearing loss induced by the noise of mills in the markets of Parakou. Methods: This was a descriptive and analytical cross-sectional study, conducted from February 3 to June 3, 2021 in the markets of Parakou. It concerned millers and sellers located within a 5 meter radius around the mills and among whom pure-tone audiometry was performed to detect a hearing loss. Subjects with no particular medical health history, under 55 years of age and having been working in these markets since more than 12 months, were included. Results: In this study, 103 subjects were selected, including 43 millers and 61 sellers. Their average age was 29 ± 13 years. The sex ratio was 0.49. The average length of service in the profession was 8 years with the extremes of 3 months and 47 years. They were exposed to noise on average 10 hours per day and 6 days a week. The average duration of weekly noise exposure was 23 h 28 min ± 13 h 32 min with the extremes of 5 h 00 min and 52 h 30 min. The average level of noise exposure was 90 dB with the extremes of 72 and 110 dB. 24 subjects reported symptoms related to noise such as headache, tinnitus, and hearing loss, with respective proportions of 22.33%, 20.39% and 06.80%. The prevalence of noise-related hearing loss was 26.21% (n = 27/103). Subjects with a notch at 4000 Hz and normal Average Hearing Loss (AHL) (20.39%) had a seven-time greater risk of developing noise-induced hearing loss (OR = 6.58;95% CI [2.54 - 18.8], p Conclusion: Hearing loss related to the noise of mills affected both millers and sellers near the mills in markets, hence the importance of regulating mills.

关键词： Noise-Induced Hearing Loss Mills Markets Parakou

speciation of Aluminum in Acidic Natural Water Equilibria with Mineral Phase Kaolinite by Chemical Equilibrium Calculation

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Chinese Chemical Letters 2000年第3期11卷 279-282页

作者： Liu, F Bi, sp Nanjing Univ Dept Chem Nanjing 210093 Peoples R China

This paper presents a computer model using thermodynamic relationships and mass balance to investigate the speciation of aluminum in acidic natural water equilibria with mineral kaolinite. Factors affecting the distribution are discussed. Compared with the case of equilibria with gibbsite, some unique characteristics are discovered. The model is verified by analyzing practical water samples. Effect of errors in thermodynamic data on calculation is evaluated by the Monte Carlo simulation.

关键词： kaolinite aluminum speciation Monte Carlo simulation

Landslide inventory validation and susceptibility mapping in the Gerecse Hills, Hungary

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Geo-spatial Information Science 2021年第3期24卷 498-508页

作者： Dávid Gerzsenyi Gáspár Albert Department of Cartography and Geoinformatics Eötvös Loránd UniversityBudapestHungary

Landslides pose a threat to property both in the populated and cultivated areas of the Gerecse Hills (Hungary). The currently available landslide inventory database holds the records from many sites in the area, but the database is out-of-date. Here we address the problem of revising the National Landslides Cadastre landslide inventory database by creating a landslide suscept-ibility map with a multivariate model based on likelihood ratio functions. The model is applied to the TanDEM-X DEM (0.4″ res.), the current landslide inventory of the area, and data acquired from geological maps. By comparing the distributions of four variables in the landslide and non-landslide area with grid computation methods, the model yields landslide susceptibility estimates for the study area. The estimations show to what extent a certain area is similar to the sample areas, therefore, its likelihood to be affected by landslides in the future. The accuracy of the model predictions was checked in the field and compared to the results of our previous study using the SRtm-1 DEM for a similar analysis. The model gave accurate estimates when certain correction measures were applied to the input datasets. The limitations of the model, the input datasets, and the suggested correction measures are also discussed.

关键词： Landslide susceptibility landslide inventory TanDEM-X Gerecse Hills landslides geomorphometry

INTERFACE CRACK IN BIPIEZOTHERMOELASTIC MEDIA

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Acta Mechanica Solida Sinica 1996年第1期9卷 13-26页

作者： Shen, sp Kuang, ZB XIAN JIAOTONG UNIV DEPT MECH ENGNXIAN 710049PEOPLES R CHINA

By using the extended version of Eshelby-Stroh's formulation and the method of analytical continuation, the problems of interface cracks are reduced to a Hilbert problem of vector form. A general explicit closed form solution for the piezothermoelastic interface crack problem is then obtained, the whole field solutions of temperature, heat flux, displacements, electric field, stress and electric induction are given, the explicit expressions for the crack opening displacements and electric potential are also provided.

关键词： piezothermoelastic interface crack heat

Laser-based manufacturing concepts for efficient production of tailor welded sheet metals

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Advances in Manufacturing 2014年第3期2卷 193-202页

作者： Marius sp?ttl Hardy Mohrbacher WISCO Lasertechnik GmbH RavensburgGermany NiobelCon bvba SchildeBelgium

Laser welding is an established manufacturing technology for a large variety of automotive applications due to its attractive properties such as low heat input, high precision and fast welding speed. Especially when welding high strength steels, which are dominantly used in today＇s car body construction, the low heat input by laser welding bears significant advantages with regard to the properties of the weld seam. The exploitation of the full application potential of laser welding in mass production requires an appropriate manufacturing concept and corresponding auxiliary technologies. The present paper demonstrates the integration of laser welding into the surrounding manu- facturing concepts by a modular setup with different levels of automation. This approach offers flexible solutions for individual needs thereby optimizing investment cost, labor cost and productivity. Recently available laser sources enable exceptionally high welding speed on thin gauged sheet metals but require efficient material handling con- cepts to utilize the full speed potential. Industrial concepts are presented offering efficient material handling and high process robustness for mass production welding.

关键词： Laser welding Tailored blanks Tailoredcoils Material handling Process robustness Laser beamsplitting Turbo-welding Weld edge conditioning

New Sesquiterpene from Senecio flammeus

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Chinese Chemical Letters 1996年第10期7卷 913-914页

作者： Hu, JF Bai, sp Jia, ZJ LANZHOU UNIV INST ORGAN CHEMSTATE KEY LAB APPL ORGAN CHEMLANZHOU 730000PEOPLES R CHINA

A new eudesmane sesquiterpene 1 beta, 4 beta, 6 alpha, 15-tetrahydroxyeudesmane isolated from Senecio flammeus and its structure determined on the basis of spectral data are reported.

关键词： New Sesquiterpene from Senecio flammeus

Microstructure and Properties of WC-Co/NiCrBSi Brazing Coating

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Journal of Materials Science & Technology 1999年第3期15卷 283-285页

作者： Lu, sp Guo, Y Chen, LS Acad Sinica Inst Met Res Shenyang 110015 Peoples R China

Through rolling technology, a flexible metal cloth consisting of metal powder (NiCrBSi powder or WC-Co powder) and organism in a certain ratio were made, which could be used as brazing coating raw materials. WC-Co/NiCrBSi wear coating was fabricated through high temperature vacuum brazing after the flexible metal clothes were assembled on 42CrMo steel surface. The tensile strengths of coating self and coating/matrix approached to 100 similar to 140 MPa and 300 similar to 360 MPa, respectively, at different brazing parameters. Effect of Co on the wear property of the coating was analyzed. The abrasive wear property of WC-Co/NiCrBSi brazing coating is better than WC-17Co/NiCrBSi flame overlaying and CoCrW overlaying.

关键词： WC Co Microstructure and Properties of WC-Co/NiCrBSi Brazing Coating

Adhesive bonding of composite aircraft structures:Challenges and recent developments

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Science China(Physics,Mechanics & Astronomy) 2014年第1期57卷 2-11页

作者： PANTELAKIS sp. TSERPES K.I. Laboratory of Technology & Strength of Materials Department of Mechanical Engineering & Aeronautics University of Patras Patras 26500 Greece

In this review paper,the challenges and some recent developments of adhesive bonding technology in composite aircraft structures are *** durability of bonded joints is defined and presented for parameters that may influence bonding *** is also,a numerical design approach for composite joining profiles used to realize adhesive *** is shown that environmental ageing and pre-bond contamination of bonding surfaces may degrade significantly fracture toughness of bonded ***,it is obvious that additional research is needed in order to design joining profiles that will enable load transfer through shearing of the *** findings,together with the limited capabilities of existing non-destructive testing techniques,can partially explain the confined use of adhesive bonding in primary composite aircraft structural parts.

关键词： adhesive bonding fracture toughness finite element analysis

Sequence variations of the S7 ribosomal protein gene in primitive cyprinid fishes: Implication on phylogenetic analysis

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Chinese Science Bulletin 2002年第19期47卷 1638-1643页

作者： Wang, XZ He, sp Chen, YY Chinese Acad Sci Inst Hydrobiol Wuhan 430072 Peoples R China

Cyprinidae is the largest fish family in the world and contains about 210 genera and 2010 species. Appropriate DNA markers must be selected for the phylogenetic analyses of Cyprinidae. In present study, the 1st intron of the S7 ribosomal protein (r-protein) gene is first used to examine the relationships among cyprinid fishes. The length of the 1st intron obtained by PCR amplification ranges from 655 to 859 bp in the 16 cyprinid species investigated, and is 602 bp in Myxocyprinus asiaticus. Out of the alignment of 925 nucleotide sites obtained, the parsimony informative sites are 499 and occupy 54% of the total sites. The results indicate that the 1st intron sequences of the S7 r-protein gene in cyprinids are rich in informative sites and vary remarkably in sequence divergence from 2.3% between close species to 66.6% between distant species. The bootstrap values of the interior nodes in the NJ (neighbor-joining) and MP (most-parsimony) trees based on the present S7 r-protein gene data are higher than

关键词： S7 ribosomal protein gene phylogeny Cyprinidae se-quence variations intron.