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Experimental study about the influence of adhesive stiffness to the bonding strengths of adhesives for ceramic/metal targets

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Defence Technology（防务技术） 2016年第2期12卷 188-200页

作者： W.sEIFERT E.sTRAssBURGER s.GREFEN s.sCHAARE Fraunhofer-Institute for High-speed Dynamics Ernst-Mach-Institute(EMI)Am Christianswuhr 279400 KandernGermany Rheinmetall Ballistic Protection GmbH Neuer Weg 2447803 KrefeldGermany

The aim of the investigations presented here was to understand how the stiffness of the adhesive affects the failure of ceramic tiles adhered to metallic backings. The working hypothesis was that varying the adhesive stiffness could have the same effect on the ballistic performance as a variation of the adhesive *** different projectile/target combinations were utilized for ballistic tests in order to generate extremely different loading conditions. With targets consisting of 6 mm aluminum oxide ceramic and 6 mm aluminum backing, complete penetration occurred in each test with 7.62 mm tungsten carbide core AP ammunition at an impact velocity of 940 m/s. In contrast, with ceramic tiles of 20 mm thickness on 13 mm steel backing,no penetration of the ceramic occurred at the impact of a 7.62 mm ball round at 840 m/*** different types of adhesive(high-strength till high-flexible) were tested in both configurations. The elongation of the adhesive layer, the deformation of the metallic backing and the failure of the ceramics were observed by means of a high-speed camera during the projectile/target *** results of the ballistic tests showed that a higher fracture strain caused a larger deformation of the backing compared to adhesives, which exhibit a high tensile strength and low fracture *** experimental results indicate that the damage behavior of the ceramic/metal composites depends on the absolute elongation of the adhesive layer. This can be controlled either by the thickness or the stiffness of the bonding layer.

关键词：氧化物陶瓷粘结层金属靶刚度强度影响实验陶瓷/金属复合材料粘接

净水摄取量作为急性缺血性脑卒中预后神经影像学预测标志物的meta分析

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国际医学放射学杂志 2024年第5期 626-626页

作者： s.Ghozy m.Amoukhteh A.Hasanzadeh P.Jannatdoust m.shafie P.Valizadeh 张昕怡

目的评估净水摄取量（NWU）预测急性缺血性脑卒中（AIs）病人预后的价值。方法按现行指南进行该系统性回顾和meta分析。检索自2023年7月1日以来Pubmed、

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methane oxidative carbonylation catalyzed by rhodium chalcogen halides over carbon supports

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Journal of Natural Gas Chemistry 2008年第1期17卷 1-7页

作者： G.R.Kosmambetoval P.E.strizhak V.I.Gritsenko s.V.Volkov L.B.Kharkova O.G.Yanko O.m.Korduban L.V Pisarzhevsky Institute of Physical Chemistry of National Academy of sciences of Ukraine pr.Nauki 31Kiev03039Ukraine V.I.Vernadsky Institute of General and Inorganic Chemistry of National Academy of sciences of Ukraine pr.PaUadina 32/34Kiev03680Ukraine V.I.Vernadsky Institute of General and Inorganic Chemistry of National Academy of sciences of Ukraine pr.Palladina 32/34Kiev03680Ukraine G.V.Kurdyumov Institute of metal Physics of National Academy of sciences of Ukraine 36Vernadskij avKyiv03680Ukraine

Gas phase carbonylation of methane is studied in the presence of molecular oxygen over pure carbon carriers and carbon supported rhodium chalcogen halides. Activated carbons and fullerene blacks have been used as carbon supports. XPs and IR-spectroscopy data show the formation of rhodium chalcogen halides in solids prepared by different methods. We have found that the productivity of acetic acid by carbon supported rhodium chalcogen halides depends strongly on the carbon carrier and the method of the catalyst preparation. Namely, the catalyst with highest productivity for the acetic acid is prepared by synthesizing the rhodium chalcogen halide over the carbon support followed by thermal destruction. We have also found that rhodium chalcogen halides over activated carbons are more active compared with fullerene supported catalysts.

关键词： catalysts methane oxidative carbonylation rhodium chalcogen halides carbon supports

manta Ray Foraging Optimization with machine Learning Based Biomedical Data Classification

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Computers, materials & Continua 2022年第11期73卷 3275-3290页

作者： Amal Al-Rasheed Jaber s.Alzahrani majdy m.Eltahir Abdullah mohamed Anwer mustafa Hilal Abdelwahed motwakel Abu sarwar Zamani mohamed I.Eldesouki Department of Information systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Industrial Engineering College of Engineering at AlqunfudahUmm Al-Qura UniversityMecca24382Saudi Arabia Department of Information systems College of Science&Art at MahayilKing Khalid UniversityAbha62529Saudi Arabia Research Centre Future University in EgyptNew Cairo11845Egypt Department of Computer and self Development Preparatory Year DeanshipPrince Sattam bin Abdulaziz UniversityAlKharjSaudi Arabia Department of Information system College of Computer Engineering and SciencesPrince Sattam bin Abdulaziz UniversityAlKharjSaudi Arabia

The biomedical data classification process has received significant attention in recent times due to a massive increase in the generation of healthcare data from various *** developments of artificial intelligence(AI)and machine learning(mL)models assist in the effectual design of medical data classification ***,this article concentrates on the development of optimal stacked Long short Term memory sequence-tosequence Autoencoder(OsAE-LsTm)model for biomedical data *** presented OsAE-LsTm model intends to classify the biomedical data for the existence of ***,the OsAE-LsTm model involves min-max normalization based pre-processing to scale the data into uniform *** by,the sAE-LsTm model is utilized for the detection and classification of diseases in biomedical *** last,manta ray foraging optimization(mRFO)algorithm has been employed for hyperparameter optimization *** utilization of mRFO algorithm assists in optimal selection of hypermeters involved in the sAE-LsTm *** simulation analysis of the OsAE-LsTm model has been tested using a set of benchmark medical datasets and the results reported the improvements of the OsAELsTm model over the other approaches under several dimensions.

关键词： Biomedical data classification deep learning manta ray foraging optimization healthcare machine learning artificial intelligence

Ameliorating the re/dehydrogenation behaviour of mgH2 by zinc titanate addition

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镁合金学报(英文) 2023年第6期11卷 2205-2215页

作者： N.A.Ali N.A.sazelee m.F.md Din m.m.Nasef A.A.Jalil Haizen Liu m.Ismail Energy storage Research Group Faculty of Ocean Engineering Technology and InformaticsUniversiti Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia Department of Electrical and Electronic Engineering Faculty of EngineeringNational Defence University of MalaysiaKem Sungai BesiKuala LumpurMalaysia Center of Hydrogen Energy Institute of Future EnergyUniversiti Teknologi Malaysia81310 UTM Johor BahruJohorMalaysia Department of Chemical and Environmental Engineering Malaysia Japan International Institute of TechnologyUniversiti Teknologi MalaysiaJalan Sultan Yahya PetraKuala Lumpur 54100Malaysia Faculty of Chemical and Energy Engineering Universiti Teknologi Malaysia81310 UTM Johor BahruJohorMalaysia Guangxi Novel Battery materials Research Center of Engineering Technology State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite StructuresSchool of Physical Science and TechnologyGuangxi UniversityNanning 530004China state Key Laboratory of Featured metal materials and Life-cycle safety for Composite structures Nanning 530004China

magnesium hydride(mgH_(2))is the most feasible and effective solid-state hydrogen storage material,which has excellent reversibility but initiates decomposing at high temperatures and has slow kinetics ***,zinc titanate(Zn_(2)TiO_(4))synthesised by the solid-state method was used as an additive to lower the initial temperature for dehydrogenation and enhance the re/dehydrogenation behaviour of mgH_(2).With the presence of Zn_(2)TiO_(4),the starting temperature for the dehydrogenation of mgH_(2)was remarkably lowered to around 290℃–305℃.In addition,within 300 s,the mgH_(2)–Zn_(2)TiO_(4)sample absorbed 5.0 wt.%of H_(2)and 2.2–3.6 wt.%H_(2)was liberated from the composite sample in 30 min,which is faster by 22–36 times than as-milled mgH_(2).The activation energy of the mgH_(2)for the dehydrogenation process was also downshifted to 105.5 k J/mol with the addition of Zn_(2)TiO_(4)indicating a decrease of 22%than as-milled mgH_(2).The superior behaviour of mgH_(2)was due to the formation of mg Zn_(2),mgO and mgTiO_(3),which are responsible for ameliorating the re/dehydrogenation behaviour of mgH_(2).These findings provide a new understanding of the hydrogen storage behaviour of the catalysed-mgH_(2)system.

关键词： Hydrogen storage solid-state storage mgH_(2) Additive Zn_(2)TiO_(4)

Analysis of Differences in Productivity,Profitability and soil Fertility Between Organic and Conventional Cropping systems in the Tropics and sub-tropics

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Journal of Integrative Agriculture 2014年第10期13卷 2299-2310页

作者： Te Pas C m Rees R m school of Geosciences University of Edinburgh Carbon management Centre Scotland's Rural College

Organic farming aims to stimulate soil fertility by avoiding the use of synthetic fertiliser inputs, relying instead on locally available natural resources. It is regarded by many as a sustainable alternative to conventional fanning because it ensures higher biodiversity, restricts environmental pollution, prevents land degradation and is easy to apply for smallholder and subsistence farmers. Although widely practiced and studied in temperate regions, little is known about the potential overall benefits of organic farming in the tropics and subtropics. This paper addresses this gap by undertaking an analysis of the differences between organic and conventional agriculture in the tropics and sub-tropics based on an extensive literature review including 88 papers with 458 data pairs. The comparison is based on three main indicators： yield, gross margin and soil organic carbon （sOC）. The differences between the organic and conventional systems for each of these main indicators is represented by the ratio of the value of the indicator in the organic system divided by the corresponding value in the conventional system. This was initially calculated for each data pair individually, and grouped by a variety of explanatory factors, such as precipitation, human development level, soil texture, crop type, organic input type, time after conversion and certification. The results demonstrate that under organic management, yields were on average 26% higher, gross margins 51% higher and soil organic carbon 53% higher than under conventional management. The highest yield increases in organic cropping systems were achieved in the least developed countries, in arid regions and on coarse soils. For gross margins, certification was the main reason for differences between organic and conventional systems. Certified farmers, mostly located in developed countries, receive significantly higher prices. Furthermore, organic farming in the driest regions results in higher profits than in other

关键词： organic farming conventional fanning tropics subtropics carbon sequestration yield soil quality soil organic carbon

Early microrecanalization of vas deferens following biodegradable graft implantation in bilaterally vasectomized rats

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Asian Journal of Andrology 2009年第3期11卷 373-378页

作者： Christopher m. simons Barry R. De Young Thomas s. Griffith Timothy L. Ratliff Erin Jones surya K. mallapragada moshe Wald Department of Urology University of Iowa Iowa City IA 52242-1089 USA Department of Pathology University of Iowa Iowa City IA 52242-1089 USA Department of Chemical and Biological Engineering Iowa State University Ames IA USA

We evaluated a biodegradable graft for reconstruction of rat vasa deferentia with long obstructed or missing segments. A total of 47 sprague-Dawley rats underwent bilateral vasectomy and were divided into groups according to length of the vas deferens affected （0.5, 1, 1.5 cm）. After 8 weeks, poly-（D,L-lactide）（PDLA） grafts were used to reconnect the vas deferens, Grafts and adjoining vasa deferentia were excised 8 and 12 weeks later and evaluated microscopically. At 8 weeks, microscopic changes included a robust inflammatory response around the grafts. All grafts were still intact but in the early stages of degradation. No microtubules, indicative of vas deferens recanalization, were identified. One specimen showed evidence of healing and neovascularization at the interface zone between the vas deferens and the graft. At 12 weeks, grafts were further degraded but still present. microscopic evaluation showed decreased inflammation. seven specimens showed neovascularization at the interface zone; two of these showed distinct epithelialized vas deferens microcanals at the graft edges. One specimen showed a microcanal spanning the entire 0.5-cm graft. A time period of 8 weeks is not ample enough for vas deferens regeneration in the setting of a biodegradable PDLA graft; however, early evidence of re-growth was seen at 12 weeks. A longer healing time should permit further biodegradation of the graft, as well as re-growth and possible eventual reconnection of the vas deferens, allowing passage of sperm. These findings suggest a potential role for biodegradable grafts in the reconstruction ofvas deferens with long obstructed segments.

关键词： graft infertility male vas deferens

Genitourinary melanoma:An overview for the clinician

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Asian Journal of Urology 2022年第4期9卷 407-422页

作者： Danielle K.DePalo Kelly m.Elleson michael J.Carr Philippe E.spiess Jonathan s.Zager Department of Cutaneous Oncology Moffitt Cancer CenterTampaFLUSA Department of surgery University of LouisvilleLouisvilleKYUSA Department of Genitourinary Oncology Moffitt Cancer CenterTampaFLUSA

Genitourinary (GU) melanoma is a rare presentation of melanoma accounting for approximately 0.5% of all *** melanomas include primary melanomas of the vulva,vagina,uterine cervix,ovary,penis,scrotum,urethra,bladder,ureter,and *** melanomas are often diagnosed in advanced stages and stigma is thought to contribute to delays in *** the likely diagnosing provider,it is imperative that dermatologists,urologists,and gynecologists are aware of these uncommon sites of *** there have been major advances in the treatment of melanomas as a whole in the last 10 years,their applications to GU melanomas have often been *** melanomas have not been included in many of the major phase II clinical trials which brought contemporary advanced treatments to market and the prognoses for GU melanomas remain *** to the rarity of GU melanomas,much of the literature provides gener alized recommendations across multiple different organs affected by GU melanomas or omits certain topics,making it difficult to appreciate the funda-mentals of the individual *** review aimed to provide background information on the pathogenesis and epidemiology of the different sites of GU melanomas and categorize data specific to the presentation,staging,treatment,and prognosis of each type of GU melanoma to guide the *** was also meant to encourage a multidisciplinary approach to the management of these patients as it spans the expertise of surgical oncologists,medical oncologists,radiation oncologist,dermatologists,urologists,and gynecologists.

关键词： Genitalia Female male melanoma Rare diseases staging Treatment Urinary tract

Unexpected ecotone dynamics of a sand dune vegetation complex following water table decline

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Journal of Plant Ecology 2016年第1期9卷 40-50页

作者： Csaba Tölgyesi márta Zalatnai LászlóErdős Zoltán Bátori Nicole Rosemary Hupp LászlóKörmöczi Department of Ecology University of SzegedSzeged H-6726Hungary Wildlife Biology Program College of Forestry and ConservationUniversity of Montana32 Campus DriveMissoulaMontanaMT 59812USA

Aims Central Hungarian inland dune ranges harbor heterogeneous grassland vegetation with an extensive network of ecotones,arranged perpendicular to topography-driven hydrologic *** area suffers from severe aridification due to climate change and local anthropogenic factors,which have led to a dramatic decline of the water *** a result,groundwater is no longer reachable for lowlying plant communities;thus,we expect they are bound to undergo profound *** study investigates how the plant communities respond to this changing environment over time by monitoring ecotones,since they are frequently the hotspots of ecosystem *** monitored five ecotones along permanent belt transects for 15 years to characterize their dynamic response,and to identify the internal structural changes of the plant communities the ecotones *** Ecotones were delineated with the split moving window *** dynamics of two ecotone parameters,location and contrast,were analyzed with linear regression models incorporating two independent variables:study year as a measure of time since the loss of groundwater,and precipitation as a possible driver of interannual *** internal changes of the patches separated by the ecotones were analyzed using plant functional *** Findings Precipitation had no detectable effect on the ecotone descriptors,but study year influenced ecotones in an unusual *** position of the ecotones appeared to be very stable in time;their dynamics are stationary,not directional as we *** contrasts had clear tendencies;two ecotones disappeared,one new one was formed and two ecotones showed no *** internal changes of the patches over time were dramatic,showing a shift toward more xeric and more open plant assemblages in most stretches of the ***,the dynamic response of the vegetation was not patch expansion ***,but fusion ***,which profoundly restructured the vegetati

关键词： groundwater decline plant functional group sand dune vegetation split moving window stationary ecotone