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A fast-running method for blast load prediction shielding by a protective barrier

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Defence Technology（防务技术） 2020年第2期16卷 308-315页

作者： S.-h.Sung j.-W.Chong Agency for Defense Development Yuseong P.O.Box 35DaeJeon395-600South Korea

This study presents a simplified blast load prediction method on structures behind a protective *** proposed method is basically an empirical approach based on Kingery-Bulamsh(K-B)chart and finite element(FE)analysis *** this end,this study divides the structure into three regions by three critical *** loads at each critical point can be calculated based on K-B chart and an approximation according to FE analysis ***,peak reflected overpressure and impulse distributed on the structure can be approximately estimated by linearly connecting blast loads at each critical *** order to confirm a feasibility of the proposed method,a series of numerical simulations were carried *** simulation results were compared with FE analysis results which are presented in the open *** such comparisons,it was found that the proposed method is applicable to predict blast loads on structures behind a protective barrier.

关键词： Blast loads Protective barrier Shock wave Fast running model Kingery-Bulmash

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

Magnetic Properties of Ni Nanoparticles and Ni(C) Nanocapsules

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journal of Materials Science & Technology 2002年第2期18卷 99-100页

作者： Z.j.Li G.h.Wen 等 ShenyangNationalLaboratoryforMaterialsScienceandInternationalCentreforMaterialsPhysics InstituteofMetalResearchChineseAcademyofSciencesShenyang110016China DepartmentofPhysics H

Structure and magnetic properties of Ni nanoparticles and Ni(C) nanocapsules were studied. The carbon atoms hardly affect the lattice of Ni to form Ni-C solid solution or nickel carbides. The large thermal irreversibility in zero-field-cooled and zero-field magnetization curves indicates magnetic blocking with a wide energy barrier. Saturation magnetization, remanent magnetization and coercivity of Ni(C) nanocapsules decrease with increasing temperature.

关键词： Nanoparticles Nanocapsules Magnetic properties

A comparison study of Ce/La and Ca microalloying on the bio-corrosion behaviors of extruded Mg-Zn alloys

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journal of Magnesium and Alloys 2020年第4期8卷 1269-1280页

作者： j.h.Chu L.B.Tong Z.h.jiang D.N.Zou Q.j.Wang S.F.Liu h.j.Zhang School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055China State Key Laboratory of Rare Earth Resources Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Lab of Automobile Materials College of Materials Science and EngineeringJilin UniversityNanling CampusChangchun 130025China

The influences of Ca and Ce/La microalloying on the microstructure evolution and bio-corrosion resistances of extruded Mg-Zn alloys have been systematically investigated in the current *** with single Ca or Ce/La addition,the Ca-Ce/La cooperative microalloying results in an outstanding grain refinement,because the fine secondary phase particles effectively hinder the recrystallized grain *** coarse Ca2Mg6Zn3 phases promote the formation of Ca3(PO4)2 or hydroxyapatite particles during the immersion process and accelerate the dissolution of the corrosion product film,which destroys its integrity and results in the deterioration of anti-corrosive *** Ce/La elements can be dispersed within the conventional Mg7Zn3 phases,which reduce the internal galvanic corrosion between Mg matrix and the secondary phases,leading to an obvious improvement of corrosion ***,the Ca-Ce/La cooperative microalloying achieves a homogenous fine-grained microstructure and improves the protective ability of surface film,which will pave a new avenue for the design of biomedical Mg alloys in the coming future.

关键词： Extruded Mg-Zn alloy Ca and Ce/La microalloying Microstructure evolution Bio-corrosion behaviors

The Gas-to-Dust Relation in the Dark Cloud L1523-Observational Evidence for CO Gas Depletion

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Chinese journal of Astronomy and Astrophysics 2008年第6期8卷 686-692页

作者： h.G.Kim B.G.Kim j.h.jung Korea Astronomy and Space Science Institute 61-1 Hwaam Yuseong Daejeon 305-348 Korea

Correlation between gas and dust column density has been studied for the dark globule L1523. The 13CO（j=1→0） emission is used for tracing the gas, and the IR emissions, for tracing the dust constituent. In order to match the beam resolution between the images, a beam de-convolution algorithm based on the Maximum Correlation Method （MCM） was applied on the Infrared Astronomical Satellite （IRAS） data. The morphology of 13CO column density map shows a close correlation to that of 100μm dust optical depth. The distribution of the optical depth at 100 μm follows that of gas column density more closely than does the flux map at either 60 or 100μm. The ratio of the 13CO column density to the 100μm optical depth shows a decreasing trend with increasing dust optical depth in the central part, indicating possible molecular gas condensation onto dust particles. The excessive decrease in the CO column density in the envelope may most probably be due to the photo-dissociation of CO molecules.

关键词： ISM: clouds ISM: dust ISM: molecules

Cyclic behavior of reinforced sand under principal stress rotation

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journal of Rock Mechanics and Geotechnical Engineering 2017年第4期9卷 585-598页

作者： Alaa h.j. Al-rkaby A. Chegenizadeh h.R. Nikraz Department of Civil Engineering School of Civil and Mechanical Engineering Curtin University Perth Australia

Although the cyclic rotation of the principal stress direction is important,its effect on the deformation behavior and dynamic properties of the reinforced soil has not been reported to *** carried out on large-scale hollow cylinder samples reveal that the cyclic rotation of the principal stress direction results in significant variations of strain components(ε,ε,εand γ) with periodic characteristics despite the deviatoric stress being constant during *** oscillation can be related to the corresponding variations in the stress components and the anisotropic fabric that rotate continuously along the principal stress *** under rotation appears to develop a plastic *** trends are observed for reinforced sand,but the shear interaction,the interlocking between particles and reinforcement layer,and the confinement result in significant reductions in the induced strains and associated irrecoverable plastic *** of the strains occur in the first cycle,and as the number of cycles increases,the presence of strains becomes very small,which is almost *** indicates that the soil has reached anisotropic critical state(ACS),where a stable structure is formed after continuous orientation,realignment and rearrangement of the particles accompanied with increasing cyclic *** in the range of 60°-135° produces more induced strains even in the presence of the reinforcement,when compared with other *** relates to the extension mode of the test in this range in which σ>σand to the relative approach between the mobilized plane and the weakest horizontal *** results in an increase in shear modulus while it appears to have no effect on the damping *** cycles of rotation result in an increase in shear modulus and lower damping ratio due to the densification that causes a decrease in shear strain and less dissipation of energy.

关键词： Cyclic rotation Principal stress direction Reinforced sand Strain components Damping ratio Shear modulus

Leaching of rare earths from fine-grained zirconosilicate ore

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journal of Rare Earths 2016年第9期34卷 908-916页

作者： h.Lim D.Ibana j.Eksteen Western Australia School of Mines Curtin University7 Conlon StreetWaterford6152 Australia Mining and Metallurgy Western Australia School of MinesLocked Bag l7Kalgoorlie6433Australia

Leaching of rare earths Y, La and Ce by sulphuric acid from fine-grained zirconosilicate ore was investigated using Ta-guchi method of experimental design. An orthogonal array of L8, 27 which denotes 7 factors at 2 levels was chosen to consider the various factors relevant to the leaching process： baking time, baking temperature, acid dosage, leaching time, leaching temperature, grind size and dilution. Statistical analysis showed that sulphation baking was a significant step for the leaching of rare earths from the whole-of-ore and optimized leaching of rare earths involved the following condition： baking for 3 h at 320 ℃ at 3.2 g acid/g ore acid dosage followed by water leaching at 20 ℃ for 1 h and dilution of 20 mL water/g ore using 300 um grind size. The effect of each leaching factor was also discussed.

关键词： rare earths yttrium lanthanum cerium zirconosilicate leaching Taguchi

Beyond first-line chemotherapy for advanced pancreatic cancer:An expanding array of therapeutic options?

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World journal of Gastroenterology 2014年第9期20卷 2224-2236页

作者： Evan j Walker Andrew h Ko University of California Helen Diller Family Comprehensive Cancer Center San Francisco CA 94115 United States

While an increasing number of therapeutic options are now available for the first-line treatment of locally advanced or metastatic pancreatic cancer,the optimal choice for treatment in the second-line setting and beyond is less well defined.A variety of cytotoxic agents,either alone or in combination,have been evaluated,although primarily in the context of small single-arm or retrospective *** regimens have been associated with median progression-free survival rates in the range of 2-4 mo and overall survival rates between 4-8mo,highlighting the very poor prognosis of patients who are candidates for such *** therapies studied in this chemotherapy-refractory setting,meanwhile,have produced even worse efficacy *** the current article,we review the clinical evidence for treatment of refractory disease,primarily in patients who have progressed on front-line gemcitabine-based *** the process,we highlight the limitations of the available data to date as well as some of the challenges in designing appropriate clinical trials in this salvage setting,including how to select an appropriate control arm given the absence of a wellestablished reference standard,and the importance of incorporating predictive biomarkers and quality of life measures whenever possible into study design.

关键词： Pancreatic cancer Refractory Second-line chemotherapy Gemcitabine

hysteresis loop behaviors of ferroelectric thin films: A Monte Carlo simulation study

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Chinese Physics B 2015年第11期24卷 492-496页

作者： C.M.Bedoya-hincapié h.h.Ortiz-varez E.Restrepo-Parra j.j.Olaya-Flrez j.E.Alfonso PCM Computational Applications Universidad Nacional de Colombia Univesidad Santo Tomás Universidad de Caldas AFIS Análisis de Fallas Integridad y Superficies Universidad Nacional de Colombia Grupo de Ciencia de Materialesy superficies Departamento de Física Universidad Nacional de Colombia

The ferroelectric response of bismuth titanate Bi4Ti3O12 （BIT） thin film is studied through a Monte Carlo simulation of hysteresis loops. The ferroelectric system is described by using a Diffour hamiltonian with three terms： the electric field applied in the z direction, the nearest dipole-dipole interaction in the transversal （x-y） direction, and the nearest dipole-dipole interaction in the direction perpendicular to the thin film （the z axis）. In the sample construction, we take into consideration the dipole orientations of the monoclinic and orthorhombic structures that can appear in BIT at low temperature in the ferroelectric state. The effects of temperature, stress, and the concentration of pinned dipole defects are assessed by using the hysteresis loops. The results indicate the changes in the hysteresis area with temperature and stress, and the asymmetric hysteresis loops exhibit evidence of the imprint failure mechanism with the emergence of pinned dipolar defects. The simulated shift in the hysteresis loops conforms to the experimental ferroelectric response.

关键词： ferroelectrics bismuth titanate hysteresis loop dipolar defects