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Slope stability of reclaimed coal mines through a new water filling index

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Journal of Rock Mechanics and Geotechnical engineering 2024年第3期16卷 828-839页

作者： Antonios Mikroutsikos Alexandros i.Theocharis Nikolaos C.Koukouzas ioannis e.Zevgolis Chemical Process&energy Resources institute Centre for Research&Technology HellasAthensGreece School of Mining and Metallurgical engineering National Technical University of AthensAthensGreece

A common reclamation practice for closed coal surface mines is filling them with water to form pit *** creation and sustainability of these lakes are significantly affected by the stability of the corresponding *** present study provides a general framework for analyzing the water filling’s effect on slope stability based on a new water filling index,which can indirectly consider the factors affecting the process and efficiently quantify the filling speed’s *** assumptions of the proposed approach are thoroughly discussed,and the range of the water filling index is ***,the safety factor is calculated using the finite element method with the shear strength reduction technique during the filling process for various conditions(soil properties,slope geometry,hydraulic conditions,and water filling speed).Results are presented as normalized stability charts for practical *** the water filling,the stability gradually decreases until the reservoir reaches a critical level of 10%e40%of the total height;it then increases to even more stable conditions than the initial ***,the present analysis allows for the preliminary stability evaluation of a coal mine during the formation of a pit lake and the appropriate quantification of the water filling’s effect.

关键词： Post-coal era Open-pit flooding Stability charts Critical level

A Hybrid Cybersecurity Algorithm for Digital image Transmission over Advanced Communication Channel Models

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Computers, Materials & Continua 2024年第4期79卷 201-241页

作者： Naglaa F.Soliman Fatma e.Fadl-Allah Walid el-Shafai Mahmoud i.Aly Maali Alabdulhafith Fathi e.Abd el-Samie Department of information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of electronics and Communications Faculty of EngineeringZagazig UniversityZagazig44519Egypt Security engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of electronics and electrical Communications engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

The efficient transmission of images,which plays a large role inwireless communication systems,poses a significant challenge in the growth of multimedia ***-quality images require well-tuned communication *** Single Carrier Frequency Division Multiple Access(SC-FDMA)is adopted for broadband wireless communications,because of its low sensitivity to carrier frequency offsets and low Peak-to-Average Power Ratio(PAPR).Data transmission through open-channel networks requires much concentration on security,reliability,and *** data need a space away fromunauthorized access,modification,or *** requirements are to be fulfilled by digital image watermarking and *** paper ismainly concerned with secure image communication over the wireless SC-FDMA systemas an adopted communication *** introduces a robust image communication framework over SC-FDMA that comprises digital image watermarking and encryption to improve image security,while maintaining a high-quality reconstruction of images at the receiver *** proposed framework allows image watermarking based on the Discrete Cosine Transform(DCT)merged with the Singular Value Decomposition(SVD)in the so-called DCT-SVD *** addition,image encryption is implemented based on chaos and DNA *** encrypted watermarked images are then transmitted through the wireless SC-FDMA *** linearMinimumMean Square error(MMSe)equalizer is investigated in this paper to mitigate the effect of channel fading and noise on the transmitted *** subcarrier mapping schemes,namely localized and interleaved schemes,are compared in this *** study depends on different channelmodels,namely PedestrianAandVehicularA,with a modulation technique namedQuadratureAmplitude Modulation(QAM).extensive simulation experiments are conducted and introduced in this paper for efficient transmission of encrypted watermarked *** addition,different variants of SC-FDMA bas

关键词： Cybersecurity applications image transmission channel models modulation techniques watermarking and encryption

Nanomotion of bacteria to determine metabolic profile

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Nanotechnology and Precision engineering 2024年第1期7卷 1-9页

作者： S.N.Pleskova e.V.Lazarenko N.A.Bezrukov R.N.Kriukov A.V.Boryakov M.e.Dokukin S.i.Surodin Research Laboratory of Scanning Probe Microscopy Lobachevsky State University of Nizhny NovgorodNizhny Novgorod 603950Russia Department of Nanotechnology and Biotechnology Nizhny Novgorod State Technical University n.a.R.E.AlekseevNizhny Novgorod 603950Russia Sarov Physics and Technology institute National Research Nuclear University MEPhISarov 607186Russia

in addition to their visible motion such as swimming(e.g.,with the help ofﬂagella),bacteria can also exhibit nanomotion that is detectable only with highly sensitive instruments,and this study shows that it is possible to detect bacterial nanomotion using an AFM detection *** results show that the nanomotion characteristics depend on the bacterial strain,and that nanomotion can be used to sense the metabolic activity of bacteria because the oscillations are sensitive to the food preferences of the bacteria and the type of surrounding medium.

关键词： Nanomotion Bacteria Cantilever Oscillation Atomic force microscopy Metabolism

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investigation of the transformation of organic matter of carbonate deposits of the Semiluksky-Mendymsky horizon under hydrothermal conditions

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Petroleum 2024年第2期10卷 216-223页

作者： S.M.Petrov A.i.Lakhova e.G.Moiseeva A.G.Safiulina institute of Petroleum Chemistry and Nanotechnologies Kazan National Research Technological University institute of Geology and Oil and Gas Technologies Kazan Federal University

The paper presents the results of studies on the transformation of the organic matter of siliceous-clayey carbonate rocks of the Semiluksko-Mendymsky horizon of the Roma.hkino oil field in a hydrothermal fluid for an hour（with a water-to-rock ratio of 33） at 340℃ and 380℃ and pressu res of 17 and 20 *** a result of hydrothermal treatment,at 340℃ and 17 MPa,based on nitrogen porosimetry and electron microscopy data,transformations of rock-forming minerals in the rock are *** lead to an increase in the volume and average diameter of mesopores in it and the formation of micropores,as well,which improve its filtration *** the same time,the amount of kerogen in the composition of the organic matter decreases and the yield of the petroleum hydrocarbon extract increases,in which,according to the SARA analysis,the content of asphaltenes increases and the content of resins,aroma.ic and saturated hydrocarbons *** the composition of aroatic hydrocarbons,the proportion of a lkyltri methyl benzenes and dibenzothiophenes increases,phenanthrene homologues appear,and in the composition of saturated hydrocarbons,the amount of iso-structure alkanes decreases relative to the content of linear *** the temperature and pressure of the hydrothermal fluid to 380℃ and 20 MPa increases the degree of kerogen conversion from 12.4% to 23.6%.At the same time,changes occurring in the component composition of petroleum hydrocarbon extracts remains similar to the experiments carried out at 340℃ and 17 MPa;the content of naphthalenes decreases,the content of dibenzothiophenes increases and C11-C17,C19-C22alkyltrimethylbenzenes *** to iR spectroscopy,with increasing temperature and pressure of the hydrothermal fluid the intensity of the absorption bands of the aroma.ic ring,aliphatic fragments,and oxygen-containing groups increases in resins;the structural-group composition of asphaltenes changes little:aroma.icity and the content of condensed

关键词： Carbonate deposits Organic matter Hydrothermal fluid Mobile hydrocarbons

Physical activity volume,frequency,and intensity:Associations with hypertension and obesity over 21 years in Australian women

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Journal of Sport and Health Science 2024年第5期13卷 631-641页

作者： Gregore i.Mielke Ding Ding Shelley e.Keating Bruno P.Nunes Ruth Brady Wendy J.Brown School of Public Health The University of QueenslandBrisbaneQLD 4006Australia Sydney School of Public Health Faculty of Medicine and HealthThe University of SydneySydneyNSW 2006Australia The Charles Perkins Centre The University of SydneySydneyNSW 2006Australia School of Human Movement and Nutrition Sciences The University of QueenslandBrisbaneQLD 4072Australia School of Nursing Federal University of PelotasPelotasRio Grande do Sul 96010-610Brazil Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4226Australia

Background:Optimal patterns of accrual of recommended levels of physical activity(PA)for prevention of hypertension and obesity are not *** overall aim of this study was to investigate whether different patterns of accumulation of PA are differentially associated with hypertension and obesity in Australian women over 21 ***,we investigated whether,for the same weekly volume of PA,the number of sessions(frequency)and vigorousness of PA(intensity)were associated with a reduction in the occurrence of hypertension and obesity in ***:Data from the 1973-1978 and 1946-1951 cohorts of the Australian Longitudinal Study on Women's Health were analyzed(n=20,588;12%-16%with a Bachelor's or higher degree).Self-reported PA,hypertension,height,and weight were collected using mail surveys every 3 years from 1998/2000 to 2019/*** estimating equation models with a 3-year lag model were used to investigate the association of PA volume(metabolic equivalent min/week)(none;33-499;500-999;≥1000,weekly frequency(none;1-2 times;3-4times;5-7 times;≥8 times),and the proportion of vigorous PA to total volume of PA(none;0%;1%-33%;34%-66%;67%-100%)with odds of hypertension and obesity from 2000 to ***:The cumulative incidence of hypertension was 6%in the 1973-1978 and 23%in the 1946-1951 cohort;27%of women in the 1973-1978;and 15%in the 1946-1951 cohort developed obesity over the ***,a higher volume of PA was associated with reduced odds of hypertension and *** the volume of PA was considered,the odds of hypertension did not vary according to the frequency or intensity of ***,increased proportion of vigorous PA to the total volume of PA was associated with a small additional reduction in the risk of obe ***:PA volume appears to be more important than the pattern of accumulation for the prevention of hypertension and *** more sessions,particularly of vigorous-intensity PA,may provide extr

关键词： Physical activity Frequency intensity incidences epidemiology Women

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Factors that influence the results of indirect decompression employing oblique lumbar interbody fusion

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World Journal of Orthopedics 2024年第8期15卷 734-743页

作者： Andrey e Bokov Svetlana Y Kalinina Mingiyan i Khaltyrov Alexandr P Saifullin Anatoliy A Bulkin Department of Neurosurgery Institute of Traumatology and OrthopedicsPrivolzhsky Research Medical UniversityNizhny Novgorod603005Russia Department of Traumatology Orthopedics and NeurosurgeryPrivolzhsky Research Medical UniversityNizhny Novgorod603005Russia

BACKGROUND indirect decompression is one of the potential benefits of anterior reconstruction in patients with spinal *** the other hand,the reported rate of revision surgery after indirect decompression highlights the necessity of working out prediction models for the radiographic results of indirect decompression with assessing their clinical *** To assess factors that influence radiographic and clinical results of the indirect decompression in patients with stenosis of the lumbar *** This study is a single-center cross-sectional evaluation of 80 consecutive patients(17 males and 63 females)with lumbar spinal stenosis combined with the instability of the lumbar spinal *** underwent single level or bisegmental spinal instrumentation employing oblique lumbar interbody fusion(OLiF)with percutaneous pedicle screw *** results of the indirect decompression were assessed using computerized tomography,while MacNab scale was used to assess clinical *** After indirect decompression employing anterior reconstruction using OLiF,the statistically significant increase in the disc space height,vertebral canal square,right and left lateral canal depth were detected(Рe median(M)relative vertebral canal square increase came toМ=24.5%with 25%-75%quartile border(16.3%;33.3%)if indirect decompression was achieved by restoration of the segment *** patients with the reduction of the upper vertebrae slip,the median of the relative increase in vertebral canal square accounted for 49.5%with 25%-75%quartile border(2.35;99.75).Six out of 80 patients(7.5%)presented with unsatisfactory results because of residual nerve root *** critical values for lateral recess depth and vertebral canal square that were associated with indirect decompression failure were 3 mm and 80 mm2 *** indirect decompression employing anterior reconstruction is achieved by the increase in disc height al

关键词： indirect decompression Anterior reconstruction Central lumbar spinal stenosis Degenerative spondylolisthesis Lateral recess stenosis Spinal instability Oblique lateral interbody fusion

Hydroxyapatite composites with carbon allotropes:Preparation,properties,and applications

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Particuology 2024年第5期88卷 239-265页

作者： Boris i.Kharisov Oxana V.Kharissova Lucy T.González Yolanda Peña Méndez igor e.Uflyand idalia Gómez de la Fuente Universidad Autónoma.de Nuevo León Ave.UniversidadCiudad UniversitariaSan Nicolás de los GarzaNuevo León 66455Mexico Tecnologico de Monterrey Escuela de Ingeniería y CienciasMonterreyNuevo Leon 64890Mexico Department of Chemistry Southern Federal UniversityRostov-on-DonRussia

Hydroxyapatite(HA)and its composites with inorganic additives,dopants,and polymers is a rapidly developing branch in the materials *** particular,carbon allotropes are widely used in these composites being widely applied for medical *** a gap of insufficient generalization of recent achievements in the field of the HA/Carbon composites,in this review we present the state of the art of the field of HA composites and hybrids with classic carbon allotropes and *** composites are known for carbon nanotubes,nanofibers,graphene and its oxidized forms,as well as,in a lesser grade,for graphite,fullerenes,nanodiamonds,carbon nanofoams,*** composites can be fabricated by a variety of classic and less-common methods,such as co-precipitation(with or without ultrasonic treatment),CVD,hot isostatic pressing,hydrothermal,spark plasma sintering,biomimetic mineralization,thermal and plasma spray,electrochemical and electrophoretic deposition,self-assembling,3D printing,electrospinning,and lyophilisation,among *** of various synthesis techniques can be also carried out for composite *** or synthetic HA can be used as it is for further interaction with carbon allotropes or it can be first prepared and then reacted with carbon counterpart;similarly,carbon allotropes can be introduced into the interaction with HA directly or they can be first synthesized,in particular from *** biocompatible composites can be produced in the form of coatings,powders,and scaffolds and can additionally contain quantitative amounts of third phases,frequently natural or synthetic *** these composites,especially with O-containing functionalizing groups,HA disadvantages could be considerably decreased with simultaneous enhancement of mechanical properties,becoming similar to human bone,chemical stability and biocompatibility,as well as possessing antibacterial ***→G reduction and higher HA decoration were obs

关键词： Hydroxyapatite Carbon nanotubes Graphene Quantum dots Fullerenes Nanodiamonds

enhancing high-temperature oxidation resistance(at 1000 °C) of nickel superalloy obtained by laser powder bed fusion via reactive electric spark treatment

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Transactions of Nonferrous Metals Society of China 2024年

作者： S.K.MUKANOV M.i.PeTRZHiK A.e.KUDRYASHOV e.A.NAUMOVA F.A.BASKOV P.A.LOGiNOV e.A.LeVASHOV National University of Science and Technology MiSiS

The high-temperature oxidation resistance of the nickel superalloy grown by the Laser Powder Bed Fusion (LPBF) has been significantly increased as a result of in-situ formation of a thermal barrier layer (α-Al2O3+ CaMoO4) during oxidative annealing of surface layers modified by electric spark treatment (eST). The reactive eST of the LPBF-built items based on nickel eP741NP alloy was carried out with low-melting Al-12%Si， Al-6%Ca-0.6%Si and Al-7%Ca-1%Mn electrodes. it was found that at eST done by Al-7%Ca-1%Mn electrode an intermetallic (β-NiAl + γ’-Ni3Al) 15 microns thick layer reinforced by spherical oxide (CaMe)O nanoparticles was formed. Formation of that structure increases the wear resistance of LPBF nickel superalloy by 4.5 times. Further oxidative annealing at 1000 °C lead to a formation of continuous two-layered coating with an inner layer of α-Al2O3and an outer layer of CaMoO4， which together act as an effective barrier preventing the diffusion of oxygen into the volume of the superalloy.

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Antibacterial HA-coatings on bioresorbable Mg alloy

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Journal of Magnesium and Alloys 2024年第5期12卷 1965-1985页

作者： K.V.Nadaraia D.V.Mashtalyar M.A.Piatkova A.i.Pleshkova i.M.imshinetskiy M.S.Gerasimenko e.A.Belov V.V.Kumeiko D.N.Kozyrev K.A.Fomenko V.V.Mostovaya B.R.Torpanov A.R.Biktimirov i.S.Osmushko S.L.Sinebryukhov S.V.Gnedenkov institute of Chemistry FeB RAS 159 Pr.100-letiya VladivostokaVladivostok 690022Russia Far eastern Federal University 10 Ajax BayRussky IslandVladivostok 690922Russia A.V.Zhirmunsky National Scientific Center of Marine Biology FeB RAS 17 St.PalchevskogoVladivostok 690041Russia Regional Clinical Dermatovenerological Dispensary 18 V St.GamarnikaVladivostok 690033Russia NMiC“Treatment and Rehabilitation Center” 3 Ivankovskoe highwayMoscow 125367Russia

in this study,a calcium-phosphate coating was formed on a Mg-Mn-Ce alloy by the plasma electrolytic oxidation(PeO).The antibiotic vancomycin,widely used in the treatment of infections caused by Staphylococcus aureus(***),was impregnated into the *** with vancomycin showed high bactericidal activity against *** mechanical and electrochemical properties of the formed coatings were studied,as well as in vitro cytotoxicity tests and in vivo tests on mature male rats were *** to SeM,eDS,XRD and XPS data,coatings had a developed morphology and contained hydroxyapatite,which indicates high *** analysis of roughness of coatings without and with vancomycin did not reveal any differences,confirming the high roughness of the *** electrochemical tests,an increase in corrosion resistance by more than two times after the application of PeO coatings was *** to the results of an in vivo study,after 28 days of the implantation of samples with calcium phosphate PeO coating and vancomycin,no signs of inflammation were observed,while an inflammatory reaction developed in the area of implantation of bare alloy,followed by *** release tests from the coatings show a sharp decrease in the concentration of the released antibiotic on day 7 and then a gradual decrease until day *** the experiment,no significant deviations in the condition and behavior of the animals were observed;clinical tests did not reveal a systemic toxic reaction.

关键词： Bioactive coatings Biocompatibility Mg alloy Plasma electrolytic oxidation Hydroxyapatite Vancomycin

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