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Journal of Central South University 2016年第2期23卷 249-257页

作者： A.karimi I.Danaee h.Eskandari m.RashvanAvei Abadan Faculty of petroleum Engineering Petroleum University of Technology Department of Chemistry K.N.Toosi University of Technology

The potential of di-(m-Formylphenol)-1,2-cyclohexandiimine as an environmentally friendly corrosion inhibitor for steel was investigated in 1 mol/L hCl using potentiodynamic polarization, electrochemical impedance spectroscopy and chronoamperometry measurements. All electrochemical measurements suggest that this compound is an excellent corrosion inhibitor for mild steel and the inhibition efficiency increases with the increase in inhibitor concentration. The effect of temperature on the corrosion behavior of mild steel with the addition of the Schiff base was studied in the temperature range from 25 °C to 65 °C. It is found that the adsorption of this inhibitor follows the Langmuir adsorption isotherms. The value of activation energy and the thermodynamic parameters such as Δhads, ΔSads, Kads and ΔGads were calculated by the corrosion currents at different temperatures using the adsorption isotherm. The morphology of mild steel surface in the absence and presence of inhibitor was examined by scanning electron microscopy(SEm) images.

关键词： corrosion inhibitor Schiffbase adsorption Langmuir adsorption isotherm

Influence of surface liquid segregation on corrosion behavior of semi-solid metal high pressure die cast aluminium alloys

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中国有色金属学会会刊：英文版 2010年第S3期20卷 837-841页

作者： E.p.mASUKU h.mLLER U.A.CURLE p.C.pISTORIUS materials Science and manufacturing Council for Scientific Industrial ResearchPretoriaSouth Africa Department of materials Science and Engineering Carnegie Mellon UniversityPittsburghUSA

The corrosion behavior(in chloride medium) of the surface layer of SSm-hpDC plates of alloys 7075-T6 and 2024-T6 was compared with that of the wrought alloys 7075-T6 and *** testing was performed in deaerated 3.5%NaCl *** separate tests,the open-circuit potential was monitored in aerated 3.5% NaCl for 30 min after *** electrochemical tests show that there is no significant difference in the pitting potential of the wrought alloys and that of the Cu-enriched surfaces of the SSm-hpDC alloys.

关键词： semi-solid metal(SSm) forming wrought aluminium alloys alloy 7075 alloy 2024 corrosion surface liquid segregation

mineralogy,m-type tetrad effect and radioactivity of altered granites at the *** Garadi shear zone,central Eastern Desert,Egypt

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Chinese Journal Of Geochemistry 2011年第2期30卷 153-164页

作者： El Nahas h.A. El Feky m.G. mira h. Nuclear materials Authority P.O. Box 530 Cairo Egypt

The G. Abu Garadi area is covered mainly by metasediments, alkali feldspar granites and stream sediments. The alkali feldspar granite is traversed by a major strike-slip fault trending in an N-S direction as well as two subordinate sets of faults trending NW to WNW for the first one and NE for the second one. These faults represent the shear zones affected by magmatic (syngenetic) as well as hydrothermal (epigenetic) activities causing alteration of the granitic rocks. The most common alteration features are albitization, greisenization and koalinitization. The mass balance calculations of the studied altered samples show enrichments in Zr, Y, Ni, U, Th and Ga and depletions in Zn, Sr, Nb, Ba, pb, Cu and V. Only the greisenized samples exhibit a significant enrichment in Nb, ∑REE budget and pronounced lanthanide tetrad effect (m-type), especially TE1,4, while weakly expressed tetrad effects are for the other albitized and koalinitized samples. mineralogically, the common accessory minerals in the altered samples include samarskite-(Y), betafite, uranothorite, zircon, fluorite and cassiterite. The greisenized granites contain high eU and eTh than the other altered types, where they are characterized by an assemblage of the radioactive minerals; samarskite-(Y), betafite, uranothorite in addition to zircon. The inter-element relationships between U and Th and also their ratios illustrate that the radioelement distribution in these granites is mainly governed by magmatic processes, in addition to post-magmatic ones. The distribution of chemical elements and the fractionation of some isovalents within the shear zone are largely controlled by the newly formed mineral phases. With respect to uranium mobilization, uranium migrated from the host alkali feldspar granites of G. Abu Garadi, while the shear zones acted as traps for the migrated uranium. moreover, U migrated in the shear zone during greisenization and albitization, and migrated out during koalinitization.

关键词： m 类型四个效果改变的花岗石 G。Abu Garadi 砍地区中央东方沙漠埃及

Regression analysis of squeezing-induced hybrid nanofluid flow in Darcy-Forchheimer porous medium

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 193-208页

作者： K.mUhAmmAD m.SARFRAZ Department of humanities and Sciences School of Electrical Engineering and Computer Science National University of Sciences and Technology Department of mathematics Quaid-i-Azam University

This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing velocity. The space between these plates contains a Darcy-Forchheimer porous medium. A mixture of water-based fluid with gold(Au) and silicon dioxide(Si O2) nanoparticles is formulated. In contrast to the conventional Fourier's heat flux equation, this study employs the Cattaneo-Christov heat flux equation. A uniform magnetic field is applied perpendicular to the flow direction, invoking magnetohydrodynamic(mhD) effects. Further, the model accounts for Joule heating, which is the heat generated when an electric current passes through the fluid. The problem is solved via NDSolve in mAThEmATICA. Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow, energy transport, and skin *** findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies. It is observed that the squeezing motion generates additional pressure gradients within the fluid, which enhances the flow rate but reduces the frictional drag. Consequently, the fluid is pushed more vigorously between the plates, increasing the flow velocity. As the fluid experiences higher flow rates due to the increased squeezing effect, it spends less time in the region between the plates. The thermal relaxation, however, abruptly changes the temperature, leading to a decrease in the temperature fluctuations.

关键词： Nanofluidics

malaria prevalence in north-eastern Nigeria:A cross-sectional study houben Ch^(1*),Fleischmann h^2,Gǜckel m^3

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Asian pacific Journal of Tropical medicine 2013年第11期6卷 865-868页

作者： houben Ch Fleischmann h Gckel m Diagnostic Center mmm group & Specialist hospital Yola Hospital RoadP.M.B.2266YolaAdamawa.StateNigeria medical mission Institute Tropical MedicineHermann Schell Str 797074 WrzburgGermany helios Kliniken Schwerin Wismarsche Str 393-39719049 SchwerinGermany

Objective:To assess the prevalence of malaria parasitemia in north-east Nigeria and to evaluate the measures for the prevention of ***:A village in north-eastern Nigeria was selected for the cross sectional study at the height of the rainy season in october 2011.A total of 550 inhabitants of a hamlet were recruited for this *** obtaining the consent individuals received a structured interview and were tested for malaria parasites in their blood *** testing positive for malaria were given a course of artemesinin-based combination therapy（ACT）.Results:A total of 497 inhabitants representing approximately 90 percent of the population participated:a quarter of the study group carried malaria parasitesexclusively plasmodium falciparum（***）-representing a *** parasite rate（pfpR） of 24.5%.Besides,53/138 in the age group of 2 to hildren tested positive for *** representing a pfpR2-10 value of 38.4%.malaria control measures were used in just under a third（157/497） of this *** these measures 28/157（17.8%） still tested positive for ***:The malaria burden is overestimated for this region in north-east *** findings support an intermediate pattern of malaria *** 30%bed nets coverage for malaria control is well below the WhO estimates for 2011.

关键词： malaria control malaria endemicity malaria prevalence malaria transmission

Use of two fungal species to induce agarwood resin formation in Gyrinops walla

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Journal of Forestry Research 2019年第2期30卷 721-726页

作者： S.m.C.U.p.Subasinghe h.I.D.hitihamu K.m.E.p.Fernando Department of Forestry and Environmental Science University of Sri Jayewardenepura Department of Botany University of Sri Jayewardenepura

Gyrinops walla Gaertn. is the only species growing in Sri Lanka that belongs to the agarwood family,Thymelaeaceae. Although agarwood resin induction and extraction from Aquilaria species of the same family have been practised for many decades in Southeast Asian region,the ability of producing agarwood resins in G. walla was discovered recently. Since previous studies were on agarwood resins formed due to natural causes, the present study was conducted to identify the potential fungal species that are capable of artificially inducing agarwood resin formation in G. walla. Since this is the first ever study conducted on artificial inducement of agarwood resin formation in ***, Aspergillus niger and Fusarium solani were selected owing to their high abundance in the naturally formed agarwood resinous tissues collected from 25 G. walla *** fungal species were separately grown in yeast extract glucose agar and used to inoculate healthy G. walla trees under aseptic conditions. Three holes were made for each tree and 2 g of fungal culture including the medium were placed in each hole. Tissue discoloration, characteristic aroma, resin content and resin constituents were checked at10 cm intervals above and below the inoculation points for a period of 1 year. Results revealed that tissue discoloration and resin content were higher in the trees inoculated with A. niger. Other than at 10 cm above and below the inoculation points, samples collected at all locations had significantly higher resin contents when inoculated with A. niger compared to F. solani. Sixteen agarwood resin constituents, which were also recorded in Aquilaria species, were identified from the discolored tissues using GC–mS analysis. Jinkohol, agarospirol and 2(2-phenyl)chromone derivatives were found in all discolored tissues collected at 10-cm intervals of the trees inoculated with both fungi. b-Seline, c-eudesmol and valerenal were found in nine of 10 sample points on the stem. c-Elemene was recor

关键词： Gyrinops walla Agarwood resin Aspergillus niger Fusarium solani Inoculation

Design of small-area multi-bit antifuse-type 1 kbit OTp memory

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Journal of Central South University 2009年第3期16卷 467-473页

作者：李龙镇 LEE J h KIm T h JIN K h pARK m h hA p B KIm Y h Department of Electronic Engineering Changwon National University Department of Computer Science and Technology Yanbian University

A multi-bit antifuse-type one-time programmable （OTp） memory is designed, which has a smaller area and a shorter programming time compared with the conventional single-bit antifuse-type OTp memory. While the conventional antifuse-type OTp memory can store a bit per cell, a proposed OTp memory can store two consecutive bits per cell through a data compression technique. The 1 kbit OTp memory designed with magnachip 0.18 μm CmOS （complementary metal-oxide semiconductor） process is 34% smaller than the conventional single-bit antifuse-type OTp memory since the sizes of cell array and row decoder are reduced. And the programming time of the proposed OTp memory is nearly 50% smaller than that of the conventional counterpart since two consecutive bytes can be compressed and programmed into eight OTp cells at once. The layout area is 214 μm× 327 μ,, and the read current is simulated to be 30.4 μA.

关键词： multi-bit OTp programming time antifuse memory data compression

Longwall mining,shale gas production,and underground miner safety and health

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International Journal of mining Science and Technology 2021年第3期31卷 523-529页

作者： D.W.h.Su p.Zhang h.Dougherty m.Van Dyke R.Kimutis Center for Disease Control and prevention(CDC) National Institute for Occupational Safety and Health(NIOSH)Pittsburgh Mining Research Division(PMRD)PittsburghPA 15236USA

This paper presents the results of a unique study conducted by the National Institute for occupational Safety and health(NIOSh)from 2016 to 2019 to evaluate the effects of longwall-induced subsurface deformations on shale gas well casing integrity and underground miner safety and *** both deep-cover and shallow-cover instrumentation sites,surface subsidence measurements,subsurface inplace inclinometer measurements,and underground pillar pressure measurements were conducted as longwall panels were *** of the deep-cover and shallow-cover test site results with those from a similar study under medium cover reveal an interesting longwall-induced response *** shallow and medium covers,measured horizontal displacements within the abutment pillar are one order of magnitude higher than those measured under deep *** the other hand,measured vertical compressions under deep cover are one order of magnitude higher than those under shallow and medium ***,FLAC3 Dsimulations of the casings indicate that,in all three cases,the p-110 production casings remain intact under longwall-induced deformations and compressions,which has serious implications for future mine design in areas where shale gas wells have been drilled ahead of mining.

关键词： Longwall mining Coal Gas miner Safety health

Cohomogeneity One de Sitter Space S1 n

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Acta mathematica Sinica,English Series 2010年第10期26卷 1915-1926页

作者： p.AhmADI S.m.B.KAShANI h.ABEDI Department of pure mathematics Faculty of Mathematical SciencesTarbiat Modares University Group of mathematics School of Sciences Bu-Ali Sina University

In this paper we study the cohomogeneity one de Sitter space S1 n. We consider the actions in both proper and non-proper cases. In the first case we characterize the acting groups and orbits and we prove that the orbit space is homeomorphic to R. In the latter case we determine the groups and consequently the orbits in some different cases and prove that the orbit space is not hausdorff.

关键词： Cohomogeneity one Lorentzian space de Sitter space

INITIAL COEFFICIENT ESTImATES FOR SOmE SUBCLASSES OF m-FOLD SYmmETRIC BI-UNIVALENT FUNCTIONS

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Acta mathematica Scientia 2016年第3期36卷 863-871页

作者： h.m.SRIVASTAVA S.GABOURY F.GhANIm Department of mathematics and Statistics University of Victoria China medical University Department of mathematics and Computer Science University of Québec at Chicoutimi Department of mathematics College of SciencesUniversity of Sharjah

In the present investigation, we consider two new general subclasses B∑m（T, λ; α）and B^∑m （τ λ;β） of Em consisting of analytic and m-fold symmetric bi-univalent functions in the open unit disk U. For functions belonging to the two classes introduced here, we derive non-sharp estimates on the initial coefficients [a-~＋ll and │a2＋1│. Several connections to some of the earlier known results are also pointed out.

关键词： analytic functions bi-univalent functions m-Fold symmetric functions m-Fold symmetric bi-univalent functions