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Stress Intensity Factor for the Interaction between a Straight Crack.and a Curved Crack.in Plane Elasticity

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Acta Mechanica Solida Sinica 2016年第4期29卷 407-415页

作者： M.R.Aridi N.M.A.nik Long Z.k.Eshk.vatov Institute for Mathematical Research Universiti Putra Malaysia College of Foundation and General Studies Universiti Tenaga Nasional Mathematics Department Faculty of Science Universiti Putra Malaysia

Formulation in terms of hypersingular integral equations for the interaction between straight and curved crack. in plane elasticity is obtained using the complex variable functions method. The curved length coordinate method and a suitable numerical scheme are used to solve such integrals numerically for the unk.own function, which are later used to find the stress intensity factor, SIF.

关键词： hypersingular integral equation complex variable function method curved length coordinate method stress intensity factor

Numerical solutions for crack. in an elastic half-plane

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Acta Mechanica Sinica 2019年第1期35卷 212-227,I0006页

作者： N.R.F.Elfak.ak.re N.M.A.nik Long Z.k.Eshk.vatov Mathematics Department Faculty of ScienceUniversiti Putra Malaysia43400 SerdangSelangorMalaysia Institute for Mathematical Research Universiti Putra Malaysia43400 SerdangSelangorMalaysia Faculty of Science and Technology Universiti Sains Islam Malaysia71800 NilaiNegeri SembilanMalaysia

The behavior of the stress intensity factor at the tips of crack. subjected to uniaxial tension σχ^∞= p with traction-free boundary condition in half-plane elasticity is investigated. The problem is formulated into singular integral equations with the distribution dislocation function as unk.own. In the formulation, we mak. used of a modified complex potential. Based on the appropriate quadrature formulas together with a suitable choice of collocation points, the singular integral equations are reduced to a system of linear equations for the unk.own coefficients. Numerical examples show that the values of the stress intensity factor are influenced by the distance from the crack. to the boundary of the half-plane and the configuration of the crack..

关键词： Elastic half-plane Multiple crack. Singular integral equation Sine-shaped crack

Sicilian serpentinite xenoliths containing abiotic organics with nanodiamond clusters as k.y model for prebiotic processes

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Geoscience Frontiers 2021年第1期12卷 255-263页

作者： Sergei k.Simak.v Vittorio Scribano nikolai N.Mel’nik Germana Barone LLC“ADAMANT”Sk.lk.vo Participant Tikhoretsky 10/1-61St.Petersburg194064Russia Department of Biological Geological and Environmental SciencesUniversity of CataniaCorso Italia 55-I-95129 CataniaItaly Lebedev Physics Institute Russian Academy of SciencesLeninsky Pr.53Moscow119991Russia

Rock.fragments from the deepest parts of a buried hydrothermal system belonging to the Mesozoic Tethys Ocean entered as xenoliths in a Miocenic diatreme,hence brought to the surface,in the Hyblean Plateau(Sicily).Some xenoliths consist of strongly serpentinized ultramafic rock. bearing blebs of abiotic organic matter,where clusters of amorphous carbon nanoparticles,including nanodiamonds,are *** an occurrence conjures up established hypotheses that diamond surfaces are suitable catalytic platforms stimulating the assemblage of complex bio-organic molecules relevant to the emergence of life on *** appearance of bio-organic molecules under primitive Earth conditions is one of the major unsolved questions on the origin of *** we report new micro-Raman spectra on blebs of abiotic organic matter from a selected *** bands were related to hydrogenated nanocrystalline diamonds,with size of nearly 1-1.6 nm,formed from organics at low pressures and *** particular,diamond surfaces can give rise to crystalline interfacial water layers that may have played a fundamental role in the early biosphere evolution as a good medium for rapidly transporting positive charges in the form of hydrated ***,proton gradients in alk.line hydrothermal vents along oceanic ridges are generally viewed as k.y pre-biotic *** general,serpentinites span the entire geological record,including prebiotic *** hydrous ultramafic rock. often display evidence of abiotic carbon species,both organic and inorganic,including nanodiamonds,being also capable to give rise to chemiosmotic processes and proton gradients necessary to the organisms,such as the"Last Universal Common Ancestor"(LUCA),in the prebiotic Earth.

关键词： Hydrothermal systems Nanocarbons Sulfides Fr-t synthesis Abiogenesis LUCA,Sicily Micro-Raman

NUMERICAL SOLUTIONS FOR A NEARLY CIRCULAR CRACk.WITH DEVELOPING CUSPS UndER SHEAR LOADING

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Acta Mechanica Solida Sinica 2011年第5期24卷 439-449页

作者： N.M.A.nik Long L.F.k.o Z.k.Eshk.vatov Department of Mathematics Faculty of ScienceUniversity Putra Malaysia Institute for Mathematical Research University Putra Malaysia

In this paper, we study the behavior of the solution at the crack.edges for a nearly circular crack.with developing cusps subject to shear loading. The problem of finding the resulting force can be written in the form of a hypersingular integral equation. The equation is then trans-formed into a similar equation over a circular region using conformal mapping. The equation is solved numerically for the unk.own coefficients, which will later be used in finding the stress intensity factors. The sliding and tearing mode stress intensity factors are evaluated for crack. and displayed graphically. Our results seem to agree with the existing asymptotic solution.

关键词： nearly circular crack numerical method Galerk.n method stress intensity factors hypersingular integral equation shear loading conformal mapping

Bak.-Hardening Response of High Martensite Dual-Phase Steel with Different Morphologies and Volume Fractions

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Acta Metallurgica Sinica(English Letters) 2014年第2期27卷 279-289页

作者： Mustafa Trk.en Sleyman Gndz Department of Metallurgy Kocaeli University Hereke Vocational School Department of Manufacturing Engineering Technology FacultyKarabk University

Bak.-hardening behaviour of carbon steel with different martensite morphologies and volume fraction was investigated. The specimens with fibrous and bulk. martensite were prestrained in tension by 4%. After this, they were unloaded and bak. hardened at 180 ℃ for 10-160 min. It was found that dual-phase steel samples which were bak. hardened at 180 ℃ for 20 rain showed an increase in the yield stress （YS） and ultimate tensile stress （UTS） but a decrease in ductility. Further increase in the bak.-hardening time of 80 or 160 min has reduced the YS and UTS, but increased the ductility. △σ （increase in stress due to bak. hardening）, YS and UTS values are higher for the microstructure containing fibrous martensite compared to the microstructure-containing bulk. martensite. It was also observed that at a given bak.ng temperature Aa, YS and UTS increased by volume of martensite.

关键词： Dual-phase steel Bak. hardening Martensitic transformation

Synthesis of ion imprinted polymers for selective recognition and separation of rare earth metals

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Journal of Rare Earths 2017年第2期35卷 177-186页

作者： Mashitah M.Yusoff nik Rohani nik Mostapa Md Shaheen Sark.r Tapan k.mar Biswas Md Lutfor Rahman Sazmal Effendi Arshad Mohd Sani Sarjadi Ajayk.mar D.k.lk.rni Faculty of Industrial Sciences and Technology University Malaysia Pahang Faculty of Science and Natural Resources Universiti Malaysia Sabah Department of Applied Sciences MIT Academy of Engineering

Lanthanide-ion imprinted polymers（L-IIPs） were synthesized by stoichiometric amounts of rare earth ions and the cavities in the polymers were created for the corresponding lanthanide ions. The maximum sorption capacities were estimated to be 125.3, 126.5, 127.6, 128.2 and 129.1 mg/g for Pr, nd, Sm, Eu and Gd, respectively at p H 6. In the selectivity study, the L-IIPs exhibited good selectivity to the specific rare earth ions in the presence of coexisting cations. The imprinting results were found to be excellent with some rare earth ions over other competitor rare earth ions with the same charges and close ionic radius.

关键词： ion-imprinted polymers rare earths separation adsorption lanthanide-ions

Isolation,characterization and identification of plant growth-promoting rhizobacteria from the rhizosphere of Acacia mangium at sandy BRIS soil

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Frontiers of Agricultural Science and Engineering 2024年第3期11卷 499-513页

作者： Zak.ah MUSTAPHA Radziah OTHMAN nik Nurnaeimah nik MUHAMMAD NASIR Dhiya Dalila ZAWAWI Mohd k.airi CHE LAH Hafizan JUAHIR School of Agriculture Science and Biotechnology Faculty of Bioresources and Food IndustryUniversiti Sultan Zainal AbidinBesut Campus22200 BesutTerengganuMalaysia Department of Land Management Faculty of AgricultureUniversiti Putra Malaysia43400 SerdangSelangorMalaysia Faculty of Plantation and Agrotechnology Universiti Technologi MARA Cawangan Pahang26400 JengkaPahangMalaysia

This study has isolated,characterized,and identified potential plant growthpromoting rhizobacteria(PGPR)with multiple PGP characteristics(N_(2)-fixation,P-and k.solubilization,IAA,and siderophores production)from the rhizosphere BRIS soil of Acacia mangium.A total of 24 pure colonies were isolated and only 8 colonies were selected for further evaluation of the growth rate in 5%organic molasses medium supplemented with 2%k.O_(3).Based on the biochemical,potential PGP characteristics and growth performance,3 superior PGPR strains were selected and identified as Paraburk.olderia unamae(UA1),Bacillus amyloliquefaciens(UA6),and Enterobacter asburiae(UAA2)by partial sequencing of the 16S rRNA *** selected bacterial strains either in single or mixed(UA1+UA6+􀀁UAA2)cultures have shown a significant biochemical estimation of the PGP *** strain has its own PGPR traits superiority with UA1 showing the best PGP characteristic followed by UA6 and *** use of mixed bacterial strains was beneficial as it showed the best performance in N_(2)-fixation,siderophores production,and significant effect on corn phenology,growth and yield compared to using a single *** types of microbes showed potential to be used as biofertilizer and should be exploited more.

关键词： Biofertilizer corn organic molasses medium PGP characteristic phytohormone potassium nitrate siderophores

Pancreatic cancer survival trends in the US from 2001 to 2014:a CONCORD-3 study

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Cancer Communications 2023年第1期43卷 87-99页

作者： Maja nikšić Pamela Minicozzi Hannah k.Weir Heather Zimmerman Maria J Schymura Judith R Rees Michel P Coleman Claudia Allemani 无 Cancer Survival Group Department of Non-Communicable Disease EpidemiologyLondon School of Hygiene&Tropical MedicineKeppel StreetLondon WC1E 7HTUK Centre for Health Services Studies University of KentCanterbury CT27NFUK Division of Cancer Prevention and Control Centers for Disease Control and PreventionAtlantaGA 30333USA Montana Central Tumor Registry Chronic Disease Prevention and Health Promotion BureauPO Box 2029511400 BroadwayHelenaMT 59620-2951USA Bureau of Cancer Epidemiology New York State Cancer RegistryNew York State Department of Health150 BroadwayAlbanyNY 12204-2719USA New Hampshire State Cancer Registry Norris Cotton Cancer Centerand Department of EpidemiologyGeisel School of MedicineDartmouth CollegeDartmouth-Hitchcock Medical CenterOne Medical Center DriveLebanonNH 03756USA Cancer Division University College London Hospitals NHS Foundation Trust250 Euston RoadLondon NW12PGUK US CONCORDWork.ng Group

Back.round:Survival from pancreatic cancer is low *** the US,the 5-year relative survival has been slightly higher for women,whites and younger patients than for their counterparts,and differences in age and stage at diagnosis[Corrections added Nov 16,2022,after first online publication:a new affiliation is added to Maja nikšić]may contribute to this *** aimed to examine trends in survival by race,stage,age and sex for adults(15-99 years)diagnosed with pancreatic cancer in the ***:This population-based study included 399,427 adults registered with pancreatic cancer in 41 US state cancer registries during 2001-2014,with followup to December 31,*** estimated age-specific and age-standardized net survival at 1 and 5 ***:Overall,12.3%of patients were black.,and 84.2%were *** 9.5%of patients were diagnosed with localized disease,but 50.5%were diagnosed at an advanced stage;slightly more among black.,mainly among *** substantial changes were seen over time(2001-2003,2004-2008,2009-2014).In general,1-year net survival was higher in whites than in black.(26.1%vs.22.1%during 2001-2003,35.1%vs.31.4%during 2009-2014).This difference was particularly evident among patients with localized disease(49.6%in whites vs.44.6%in black. during 2001-2003,60.1%vs.55.3%during 2009-2014).The survival gap between black. and whites with localized disease was persistent at 5 years after diagnosis,and it widened over time(from 24.0%vs.21.3%during 2001-2003 to 39.7%vs.31.0%during 2009-2014).The survival gap was wider among men than among ***:Gaps in 1-and 5-year survival between black. and whites were persistent throughout 2001-2014,especially for patients diagnosed with a localized tumor,for which surgery is currently the only treatment modality with the potential for cure.

关键词： pancreatic cancer race/ethnicity stage net survival population-based cancer registries

Synthesis, spectroscopic characterization, and thermal decomposition k.netics of some lanthanide(III) nitrate complexes of 2-(N-o-hydroxyacetophenone) amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene

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Journal of Rare Earths 2008年第4期26卷 463-468页

作者： k. Mohanan M. Thank.mony B. Sindhu k.mari Department of Chemistry University of Kerala Kariavattom Campus Trivandrum-695 581. Kerala India

Complexes of La（Ⅲ）, Ce（Ⅲ）, Pr（Ⅲ）, nd（Ⅲ）, Sm（Ⅲ）, Eu（Ⅲ）, Gd（Ⅲ）, Dy（Ⅲ）, Yb（Ⅲ）, and Lu0ID with 2-（N-o- hydroxyacetophenone）amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene （HAAT） formed by the condensation of o-hydroxyacetophenone and 2-amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene were synthesized and characterized on the basis of elemental analyses, molar conductance measurements, magnetic susceptibility data, UV-Visible, IR, and NMR spectral studies. The spectral data revealed that the ligand acted as a neutral tridentate coordinating to the metal ion through ONO donor sequence. A coordination number nine was proposed for the complexes. Thermal decomposition studies of the ligand and lanthanum（Ⅲ） complex were carried out and k.netic parameters were calculated using Coats-Redfem equation. The decomposition reactions followed random nucleation mechanism with one nucleus on each particle.

关键词： lanthanides o-hydroxyacetophenone molar conductance magnetic susceptibility thermal study rare earths