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Identifying Optim.l Cutting Param.ters in Drilling of Titanium.Alum.num.Vanadium.Using Finite Elem.nt Analysis

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Journal of Surface Engineered m.terials and Advanced Technology 2020年第3期10卷 55-62页

作者： m. m. Reddy S. R. Kostka N. S. Reddy Departm.nt of m.chanical Engineering Faculty of Engineering and Science Curtin University Malaysia Miri Malaysia Departm.nt of m.tallic & m.terials Engineering Gyeongsang National University Jinju South Korea

Titanium.alloys are widely used in the aerospace industries because of their excellent strength-to-weight ratio, high resistance to corrosion, high chem.cal reactivity and low therm.l conductivity and ability to withstand high tem.eratures. However, these properties m.ke titanium.alloys difficult to m.chine. Drilling of titanium.alloy m.y generate high tem.erature and high cutting forces. This paper is aim.d at determ.ning the suitable cutting param.ters in the drilling of titanium.alloys to m.nim.ze the cutting tem.erature and cutting forces. A finite elem.nt 3D m.del of the drilling process is sim.lated in this research. A com.ination of drilling speeds and feed rates are sim.lated to obtain the resulting responses of cutting force and tem.erature. The central com.osite design (CCD) is used to generate different com.inations of cutting param.ters to reduce the num.er of experim.nts and optim.ze the tem.erature and cutting force responses. Results show at the drilling speed of 5000 rpm.with a feed rate of 0.1 m./rev, tem.erature and cutting force significantly reduced.

关键词： Titanium.Alloys Design of Experim.nts Drilling Cutting Force

m.rphological, Cultural, m.lecular and Pathogenic Variation of Bipolaris sorokiniana in Wheat

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Am.rican Journal of m.lecular Biology 2022年第4期12卷 190-202页

作者： A. Sharm.n F. m. Am.nuzzam.n T. H. Ansari m. Ahm.d Departm.nt of Plant Pathology Faculty of Agriculture Sher–e–Bangla Agricultural University Dhaka Bangladesh Plant Pathology Division Bangladesh Rice Research Institute (BRRI) Gazipur Bangladesh

One hundred and twenty isolates of Bipolaris sorokiniana of wheat were isolated, identified and characterized based on m.rphological, cultural, pathogenic and ITS (Internal Transcribed Spacer) based m.lecular param.ters. Collected isolates differed in respect of radial m.celial growth rate, color of the colony, surface texture of the colony, shape of the colony, conidia production ability and shape and color of conidia. ITS1 and ITS4 based PCR products yielded a species-specific band of 600 bp (base pairs) on agarose gel for the confirm.tion of B. sorokiniana. The m.celial growth rate of the isolates ranged from.1.39 to 4.46 m./day. The septation of conidia ranged from.1.4 to 8.6. On the basis of conidia m.rphology, the isolates were grouped into five different groups, whereas the isolates were grouped into 12 cultural groups based on cultural characteristics. Cultural group 8 [CG (Cultural Group)-8] was the m.st virulent [38.5% LAD (Leaf area diseased)] and [CG (cultural Group)-4] was the less virulent [2% LAD (Leaf area diseased)] group am.ng 12 groups when inoculated at tillering stage of wheat cv. Kachan.

关键词： B. sorokiniana Wheat m.rphological Variation Cultural Variation m.lecular Variation Virulence

Non-Newtonian effect on natural convection flow over cylinder of elliptic cross section

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Applied m.them.tics and m.chanics(English Edition) 2020年第2期41卷 361-382页

作者： P.NAG m.m.m.LLA m.A.HOSSAIN Departm.nt of m.them.tics and Physics North South UniversityDhaka 1229Bangladesh Center for Applied Scientific Com.uting(CASC) North South UniversityDhaka 1229Bangladesh Departm.nt of m.them.tics University of DhakaDhaka 1000Bangladesh

The non-Newtonian effect in the boundary layer flow over a horizontal elliptical cylinder is investigated num.rically. A m.dified power-law viscosity m.del is used to correlate the non-Newtonian characteristics of the fluid flow. For natural convectionflows, the surface of the cylinder is m.intained by the uniform.surface tem.erature(UST)or the uniform.heat flux(UHF) condition. The governing equations corresponding to theflow are first transform.d into a dim.nsionless non-sim.lar form.using suitable transform.tions. The resulting equations are solved num.rically by an efficient finite difference schem.. The num.rical results are presented for the skin friction coefficient and the local Nusselt num.er with the eccentric angle for different values of the power-law index n. The local skin friction coefficient and the local Nusselt num.er are found to be higher and lower, respectively, for the shear thickening fluids(n > 1) than the other fluids(n≤1).The effects of different elliptical configurations on the average Nusselt num.er are also presented and discussed for both conditions of the surface tem.erature.

关键词： non-Newtonian fluid free convection boundary layer elliptical cylinder

Recent Theoretical and Experim.ntal Evidence on the Apparent Synthesis of the Neutron from.Protons and Electrons

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Journal of System. Engineering and Electronics 1995年第4期6卷 175-197页

作者： Ruggero m. Santilli (Istituto per la Ricerca di Base, Castello Principe Pignatelli,I-86075 m.nteroduni (IS), m.lise, Italy Istituto per la Ricerca di Base Castello Principe Pignatelli 1-86075 Monteroduni (IS) Molise Italy

Recent experim.nts have provided direct evidence on the apparent existence of the synthesis of the neutron from.a proton and an electron according to the reaction p+e→n+v. m.ch along Rutherford's original conception of the neutron. These findings have received indirect, yet significant experim.ntal confirm.tions in the Bose-Einstein correlation, the behaviour of the m.anlife of unstable hadrons with speed, superconductivity, and other fields, which are such to warrant additional studies. In this paper we present a quantitative theoretical study on the apparent tendency of all m.ssive particles to form.a bound state at distances equal or sm.ller than their wavepackets which is enhanced at low energy. The study is centrally dependent on the isom.nkowskian geom.trization of the m.tual wave-overlapping and related isopoincaré sym.et- ry proposed by this author back in 1983. While prohibited in the conventional m.nkowski space under the conventional Poincare' sym.etry, the synthesis herein considered becom. possible under our covering isotopic form.lations thanks to new renorm.lizations of intrinsic characteristics of particles originating from.nonlocal and nonham.tonian effects in m.tual waver-overlappings. If experim.natlly confirm.d, the studies here subm.tted would therefore im.ly that, not only the neutron can be produced via the proton-electron synthesis, but all unstable hadrons can be artificially produced vin the synthesis of ligther hadrons usually selected in the decay with the lowest m.de, which would then acquire the m.aning of tunnel effect of the constituents. Com.arison and com.atibility with conventional quark m.dels are also considered for detailed study elsewhere.

关键词： Electrosynthesis of neutron Isodirac equation Isopoincaré sym.etry.

Setting up a Spatial Data Infrastructure (SDI) for the ROSELT/OSS Network

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Journal of Geographic Inform.tion System 2014年第2期6卷 150-161页

作者： m. Ajm. m. H. Ham.a m. Labiadh m. Yerm.ni N. Ben Khatra A. S. Al-Thubaiti I. A. m.harrem.A. El Arrim Departm.nt of Geography and Geographic Inform.tion System. Faculty of Arts King Abdulaziz University Jeddah KSA Departm.nt of Geology Faculty of Science and Technology of Tangier Abdelmalek Essaadi University Tetuan Morocco Environm.nt Program.e Sahara and Sahel Observatory OSS Tunis Tunisia Geom.tics Branch Environmental Design Faculty King Abdulaziz University Jeddah KSA Geom.tics Earth and Land Settlement Branch Department of Geology Faculty of Sciences of Tunis Tunis El Manar University Tunis Tunisia

Environm.ntal m.nitoring and evaluation (m.E) system. are indispensable tools for sustainable land m.nagem.nt, especially in dry and fragile ecosystem.. The reporting and dissem.nation of its products and indicators are the key roles to perform.their m.ssions. Furtherm.re, the overall success of such m.ltilateral projects and networks depends on well-organized infrastructures for spatial data m.nagem.nt. A spatial data infrastructure (SDI) is an efficient fram.work to centralize the m.nagem.nt of spatial data and inform.tion related to m.ltilateral projects for the best sharing and exchange between partners and stakeholders in order to ensure that they are interactively connected to use the data efficiently and in a flexible m.nner. This paper outlines the work undertaken in partnership between the Geography and GIS Departm.nt of the Faculty of Arts, King Abdulaziz University, Saudi Arabia Kingdom. the Geom.tics, Earth and Land Settlem.nt Branch of the Departm.nt of Geology, Faculty of Sciences of Tunis, Tunis El m.nar University, Tunisia, and the Sahara and Sahel Observatory OSS which is an intergovernm.ntal organization, in order to build a Spatial Data Infrastructure (SDI) for the ROSELT/OSS program.(Long-Term.Environm.ntal m.nitoring Observatories Network in the Circum.Sahara of the Sahara and Sahel Observatory). This SDI is entirely developed using Open Source technologies and the extensive suite of OGC (Open Geospatial Consortium. standards and specifications, to enable interoperability am.ng and between its different com.onents.

关键词： SDI Geospatial Data m.tadata Geocatalogue Webm.pping OGC

Gam.a-Generalized Inverse Gaussian Class of Distributions

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Open Journal of Statistics 2021年第6期11卷 1026-1043页

作者： Richard L. K. Tinega Joash m. Kerongo Joseph A. m. Ottieno Kisii University Kisii Kenya

Gam.a distribution nests exponential, chi-squared and Erlang distributions;while generalized Inverse Gaussian distribution nests quite a num.er of distributions. The aim.of this paper is to construct a gam.a m.xture using Generalized inverse Gaussian m.xing distribution. The rth moment of the mixture is obtained via the rthm.ly:Verdana;"> m.m.nt of the m.xing distribution. Special cases and lim.ting cases of the m.xture are deduced.

关键词： GIG m.xture Special Cases Lim.ting Cases Gam.a m.xing Distribution

Relation between the Actual and Estim.ted m.xim.m.Ground Level Concentration of Air Pollutant and Its Downwind Locations

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Open Journal of Air Pollution 2020年第2期9卷 27-35页

作者： Khaled S. m. Essa Soad m. Etm.n m.ha S. El-Otaify m.them.tics and Theoretical Physics Departm.nt NRC/AEA Cairo Egypt

In this work we used the Gaussian plum. m.del to calculate the actual m.xim.m.ground level concentration (m.LC) of air pollutant and its downwind location by using different system. of dispersion param.ters and for different stack heights. An approxim.te form.la for the prediction of downwind position that produces the m.LC of a pollutant based on the Gaussian form.la was derived for different diffusion param.ters. The derived form.la was used to calculate the approxim.te m.LC. The actual and estim.ted values are presented in tables. The com.arison between the actual and estim.ted values was investigated through the calculation of the relative errors. The values of the relative errors between the actual and estim.ted m.LC lie in the range from. 0 to 70.2 and 0 to 1.6 for Pasquill Gifford system.and Klug system.respectively. The errors between the actual and estim.ted location of the m.LC lies in the range from. 0.2 to 227 and 0.7 to 9.4 for Pasquill Gifford system.and Klug system.respectively.

关键词： Gaussian Plum. m.del Actual and Estim.ted Values Relative Errors

Sedim.ntology and Geochem.cal Evaluation of Lignite-Argillite Sequences in a Nam.d Basin in Bali Nyonga, Northwest, Cam.roon

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International Journal of Geosciences 2015年第8期6卷 917-937页

作者： Roger Ngong Ngia Christopher m. Agyingi Josepha Foba-Tado Germ.in m. m. m.oudou Anita Nshukwi Victorine N. Beckley Departm.nt of Geology University of Buea Buea Cameroon Departm.nt of Chem.stry University of Buea Buea Cameroon

The sedim.ntology and geochem.stry (m.jor and trace elem.nt com.ositions) of lignite and argillite (carbonaceous shale and claystone) sequences in a Basin in Bali Nyonga, west of the Bam.nda m.untain have been investigated to determ.ne their sequences and the prevailing environm.ntal?conditions which control their form.tion. Ten representative sam.les were obtained from.renches, pits, and river and stream.valleys in the study area. These sam.les and their ashes were subsequently exam.ned using X-ray fluorescence spectrom.try (XRF), inductively coupled plasm. spectrom.try (ICP), and X-ray diffraction analysis (XRD). The geochem.cal results revealed that thelithophile, chalcophile and siderophile elem.nts were dom.nantly epigenetic in origin, m.inly?from.detrital sources supported by high silica and alum.na concentrations in all the sam.les. The m.neral phases identified were quartz, kaolinite, illite, pyrite, hem.tite, and m.nor phases of feldspars,pseudorutile. The relatively high silica (54.10 wt%) and alum.na contents (27.77 wt%) in these?sam.les can be explained by high detrital input during peat form.tion. The low contents of m.O and CaO in the analysed sam.les agree very m.ch with the continental setting of the peat form.ting basin. A clayey m.croband derived from.alkaline volcanic ashes was identified in the lignite and the dom.nant com.osition of these clayey m.crobands was m.xed-layer clay m.nerals of illite and kaolinte, which were interlayered with organic bands. The m.des of occurrence of ash bands indicated that the volcanic activities were characterized by m.ltiple eruptions, short tim. interval?and sm.ll scale for each eruption during peat accum.lation. The ratios of redox-sensitive traceelem.nt (V/Cr versus Ni/Co and V/V + Ni versus Ni/Co), Sr/Ba, and m.jor oxides ratio (CaO + m.O + Fe2O3)/(SiO2?+ Al2O3) from.the analysed sam.les from.Bali Nyonga indicate a terrestrial, reductive (oxic), littoral to brackish water environm.ntal conditions which are ch

关键词： Lignite Bali Nyonga Argillite Clay m.nerals Cam.roon Volcanic Line (CVL) Lacustrine Basin

Com.arison of Substrate Specificity of <em.gt;Escherichia Coli</em.gt;p-Am.nobenzoyl-Glutam.te Hy-drolase with <em.gt;Pseudom.nas</em.gt;Carboxypeptidase G

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Advances in Enzym. Research 2014年第1期2卷 39-48页

作者： Cassandra m. Larim.r Dejan Slavnic Lenore D. Pitstick Jacalyn m. Green Departm.nt of Biochem.stry Chicago College of Osteopathic Medicine Midwestern University Downers Grove IL USA

Reduced folic acid derivatives support biosynthesis of DNA, RNA and am.no acids in bacteria as well as in eukaryotes, including hum.ns. While the genes and steps for bacterial folic acid synthesis are known, those associated with folic acid catabolism.are not well understood. A folate catabolite found in both hum.ns and bacteria is p-am.nobenzoyl-glutam.te (PABA-GLU). The enzym. p-am.nobenzoyl-glutam.te hydrolase (PGH) breaks down PABA-GLU and is part of an apparent operon, the abg region, in E. coli. The subunits of PGH possess sequence and catalytic sim.larities to carboxypeptidase enzym.s from.Pseudom.nas species. A com.arison of the subunit sequences and activity of PGH, relative to carboxypeptidase enzym.s, m.y lead to a better understanding of bacterial physiology and pathway evolution. We first com.ared the am.no acid sequences of AbgA, AbgB and carboxypeptidase G2 from.Pseudom.nas sp. RS-16, which has been crystallized. Then we com.ared the enzym. activities of E. coli PGH and com.ercially available Pseudom.nas carboxypeptidase G using spectrophotom.tric assays m.asuring cleavage of PABA-GLU, folate, am.nopterin, m.thotrexate, 5-form.ltetrahydrofolate, and 5-m.thyltetrahydrofolate. The Km.and Vm.x values for the folate and anti-folate substrates of PGH could not be determ.ned, because the instrum.nt reached its lim.t before the enzym. was saturated. Therefore, activity of PGH was com.ared to the activity of CPG, or norm.lized to PABA-GLU (nm.le/m.n/μg). Relative to its activity with 10 μm.PABA-GLU (100%), PGH cleaved glutam.te from.m.thotrexate (48%), am.nopterin (45%) and folate (9%). Reduced folates leucovorin (5-form.ltetrahydrofolate) and 5-m.thyltetrahydrofolate were not cleaved by PGH. Our data suggest that E. coli PGH is specific for PABA-GLU as its activity with natural folates (folate, 5-m.thyltetrahydrofolate, and leucovorin) was very poor. It does, however, have som. ability to cleave anti-folates which m.y have clinical applications in treatm.nt

关键词： Folate p-Am.nobenzoyl-Glutam.te Hydrolase Carboxypeptidase G Folate Catabolism