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For the purpose of manufacturing the automotive B-pillars with tailored properties, based on the proposed partition induction heating-quenching process, the partition controllable induction heating-stamping process of high-strength boron alloyed steel plates with designable temperature patterns is experimentally investigated. The temperature distribution of the various low temperature region patterns on the steel plates can be arbitrarily customized after heating for 30 s by properly arranging the magnetizer groups. Furthermore, the temperature field of the test B-pillar is customized. The temperature in the low temperature region of the heated B-pillar is 600 °C, which is lower than the start temperature of austenite transformation (AC1 = 750 °C), while the temperature in the high temperature region is 950 °C, which realizes fully austenization. After stamping and quenching, different microstructures are generated in the test B-pillar corresponding to the different temperature regions. The microstructures of the stamped test B-pillar in the low temperature region are mixture microstructures of ferrite + pearlite, while the fine lath martensite microstructures are transformed in the high temperature region. In terms of mechanical properties, the tensile strengths according to the low temperature region and high temperature regions are 438 and 1610 MPa, while the uniform elongation is 14.8% and 6.5% respectively, which meets the design requirements of the B-pillars with tailored properties. The specimens with a tensile strength difference ratio greater than 1: 3.5 and an elongation difference ratio greater than 1: 2.2 are obtained, which indicates the partition controllable induction heating-stamping process provides a new way to achieve automobile lightweight and significantly increasing the safety.

The slender special-shaped shells possess both shell and beam characteristics, which are widely used in practical engineering. A slender special-shaped shell under bending with some complex cracks, such as a frost flower-shaped crack and circumferential periodic cracks in a pipeline, is actually a typical three-dimensional complex crack problem with many different singular stress fields and stress intensity factors. In the present article, a very simple and practical technique based on the elementary mechanics and the concept of the conservation law is proposed to determine the stress intensity factors. The results from present method are shown to agree well with available solutions and FEM. In particular, the present method can also be easily applied to the other similar cracked structural shells.

We propose an effective design of a 2-mm-thick tungsten anti-scattering grid for medium-energy X-ray imaging. First, the Monte Carlo simulation is carried out firstly, which indicates that the ratio of direct to scattered radiation can reach as high as 1.54. The grid for the testing is produced using precision mechanical drilling technology, with the typical size of 52.1×52.1 mm(2). Clear edge of the sample can be visualized in the image when the designed grid is used and the quality of the image is substantively improved.

Conversion of perfluoroalkyl acid (PFAA) precursors in the environment has been a hotspot research in recent years. This study firstly determined the spatial distribution of PFAAs and their precursors including 8:2 fluorotelomer unsaturated acid (8:2 FTUCA), perfluorooctane sulfoneamide (FOSA), and diperfluorooctane sulfonamido ethanol-based phosphate (di-SAmPAP), then investigated the conversion of the potential precursors in the seawater and sewage treatment plants (STPs) effluents. The results indicated that the target pollutants showed a typical concentration gradient from nearshore to offshore. And the obviously increased concentration of perfluorinated carboxylic acids (△[PFCAs]) after oxidation treatment can verify the existence of PFAA precursors in the seawater and STP effluents. The concentrations of PFCAs with carbon atom numbers 4–9 (PFCAC4-C9) revealed the most increase. Moreover, the levels of △[PFCAs] and the ratios of △[PFCAs] to their concentration before oxidation (△[PFCA]/[PFCA]before oxidation) indicated obvious spatial variations in the seawater and STP effluents. The higher levels of △[PFCAC4-C12] and the lower ratios of ∑△[PFCAC4-C12]/∑[PFAA]before oxidation were observed in the STP effluents, which implied that precursors might be decomposed during the sewage treatment process. These results suggested the STP effluents might have an important effect on the PFAAs levels of seawater.

An open-celled porous Cu has been successfully prepared by using rock candy particles as space-holders. Resultant material exhibits uniformly distributed and interconnected pores. Results of damping test show that a relaxational internal friction peak arises at around 260 °C. Corresponding to the appearance of this peak the storage modulus has a softening valley. This peak has been ascribed to the sliding of grain boundaries under the applied stresses during damping test. It is also found that compared with the solid Cu, the damping capacity of the porous Cu has been significantly enhanced due to the effect of pores and the micro-plastic deformation in the Cu matrix.

Effects of aging on the microstructures and damping behaviors of a porous CuAlMn shape memory alloy were studied. It is found that after aging at 350 °C both the damping capacity of the alloy in the martensite state and the height of the internal friction peak arising from the reverse martensitic transformation increase due to the refining of martensitic structure and the annihilation of quenched-in vacancies. It is also found that the atomic ordering and the annihilation of quenched-in vacancies can promote the reverse martensitic transformation to take place, resulting in a significantly decreased temperature of the internal friction peak.

The freight railway line connecting Hailaer and Aershan in Inner Mongolia was improved to a passenger railway line, where roadbed surface layer was improved by the formation rehabilitation machine. Deteriorated ballast was reused after being crushed and mixed with river sand. Laboratory tests were conducted to firstly obtain the initial gradations of the aggregates including the deteriorated ballast, crushed deteriorated ballast, river sand and rock powder. Then the weight ratio of the crushed deteriorated ballast, sand and rock powder was investigated to make the mixed filler meet the gradation requirement specified in Chinese national railway criterion. The weight ratio was finally selected as 6:4:0 by considering the influence of seasonal freeze-thaw and wind-blow sand intrusion on roadbed stability. Field tests were also performed to obtain the sub grade reaction modulus K 30 and bearing capacity of the improved roadbed. The tested basic bearing capacity of the improved roadbed is 0.21 MPa and larger than the regulated lower threshold 0.18 MPa, which indicates that the weight ratio of the backfill aggregates provided by laboratory tests satisfies the compacting criterion.

Stress-relaxation method was first used by Liu and Jonas in 1980s for following the kinetics of strain induced precipitation of carbonitrides in austenite. Since then, the method has been widely employed for studying not only the precipitation kinetics but also the recovery and recrystallization processes in steels and other alloys. In the present paper, the principle and the worldwide usage of the method were reviewed. The dependence of stress relaxation rate on the occurrence of precipitation, recovery and recrystallization was interpreted based on a dislocation model. The capabilities and the limitations of the method were discussed and ways to overcome the existing limitations were also proposed.

We analyzed the effects of the polymorphisms of the follicle-stimulating hormone receptor (FSHR) gene on egg production in a Beijing You chicken population divergently selected for egg number, egg weight, and BW across 3 generations. The FSHR gene encodes the receptor of follicle-stimulating hormone, which controls follicular development and recruitment in the ovary. Seven SNP of the FSHR gene were investigated in 768 pedigreed hens from the G2 generation. Association analysis revealed that g.-310AG, g.-181AT, and g.159CT were associated with egg number at different weeks of age (P0.05) and that g.75470AG and g.75860GA were associated with egg weight at first egg (P0.05). The favorable allele of g.-181AT and g.159CT had increased frequencies not only in the high line but also over the 2 generations (G2 vs. G1) within the high line. To confirm the association study, we tested for FHSR mRNA expression level in the chicken ovaries. The results showed that the homozygous favorable genotypes of g.-181AT and g.-310AC increased the FSHR mRNA expression level compared with the other genotypes (P = 0.001 and P = 0.026, respectively). Hence, our findings implied that the SNP g.-181AT could be a potential genetic marker for egg performance in the Beijing You chicken, but further replications of our study in other chicken populations are needed to verify such effects detected here.

A model, which can be used to illustrate the process of nucleation of hydrogen induced cracking (HIC) in steels during sour service, was developed with the aid of Gibbs theory. A set of criteria for crack nucleation were then derived from the model. Metallurgical parameters influencing the criteria and thusly the susceptibility of the material to HIC, which are measurable and controllable in industrial processing, were also advanced in the present article.

Growth and reproduction are 2 economically important traits in the poultry industry. Janus kinase 2 (JAK) participates in the JAK2/signal transducer and activator of transcription 5 growth hormone signaling pathway, which plays important roles in the processes of growth and reproduction. The present study was designed to investigate the association of JAK2 SNP and haplotypes with growth as well as with reproductive traits in chickens. Fourteen JAK2 SNP were identified by pooled DNA sequencing, and 5 of these were genotyped for 768 Beijing You hens by using a matrix-assisted laser desorption/ionization-time of flight mass spectrometry assay. For 5 growth traits, BW at 17 wk of age was significantly associated with JAK2 C28109928T and A28135099G (P < 0.05). The 2 SNP were strongly related to BW at first egg, egg weight at first egg, and egg weight at 36 wk of age (P < 0.05). The SNP JAK2 C28122751T was found to be associated with BW at first egg and egg weight at 36 wk of age (P = 0.041 and P = 0.046, respectively), whereas JAK2 G28132240C was related to egg number at 40 wk of age (P < 0.01). Further haplotype analyses showed that 4 haplotypes checked in the population had no distinct influence on growth traits but were associated with 7 reproductive traits, namely, age at first egg; BW at first egg; egg weight at first egg; egg weight at 36 wk of age; and egg numbers at 32, 36, and 40 wk of age (P < 0.05). The results indicated that the JAK2 polymorphisms could be potential molecular markers to improve laying performance and growth traits in chickens.

A magnetic fluid is a stable colloidal solution composed of magnetic particles, surfactant, and a carrier fluid. Magnetic fluids have numerous applications. In this study, we used the computational fluid dynamics model to simulate the behavior of a magnetic fluid in a 2-D square under different conditions such as different positions and intensities of the magnetic source. The preliminary model was established and used in conjunction with experimental data obtained from a present study, in order to determine the influence of particle size and mass fraction on fluid behavior. Our results show that particles with a smaller size have better ability to dissipate heat, and a larger mass fraction would provide a stronger driving force which leads to the velocity and temperature profile. We anticipate that our model would be useful to develop newer applications of magnetic fluids and magnetic flow.

This paper will discuss the design and construction of BESIII, which is designed to study physics in the tau-charm energy region utilizing the new high luminosity BEPCII double ring e+e- collider. The expected performance will be given based on Monte Carlo simulations and results of cosmic ray and beam tests. In BESIII, tracking and momentum measurements for charged particles are made by a cylindrical multilayer drift chamber in a 1 T superconducting solenoid. Charged particles are identified with a time-of-flight system based on plastic scintillators in conjunction with dE/dx (energy loss per unit pathlength) measurements in the drift chamber. Energies of electromagnetic showers are measured by a CsI(Tl) crystal calorimeter located inside the solenoid magnet. Muons are identified by arrays of resistive plate chambers in the steel magnetic flux return. The level 1 trigger system, Data Acquisition system and the event filter system based on networked computers will also be described., 57 pages, 75 figures

In view of the problem of convergence of positioning and inaccuracy of social functioning for a large number of local colleges and universities in our country, this paper draws lessons from Ernest Boyer’s new paradigm of scholarship and its enlightenment on the diversified development of scholarship in America’s local colleges and universities, re-examines the mission of local colleges and universities for the local services in our country, and puts forward suggestions on diversified development of scholarship for local colleges and universities.

Milk yield from 158 Brangus cows bred to 6 sire breeds (Bonsmara, Brangus, Charolais, Gelbvieh, Hereford, Romosinuano) was measured for 3 yr to estimate relationships of milk yield of cows and postweaning ADG of their calves on 2 postweaning systems (dry lot or wheat pasture). Milk yield was measured monthly 6 times per year and averaged over 1 mo. Calf postweaning ADG was calculated from the initiation of postweaning management treatments in the fall to the end of spring grazing in April. Calf ADG was regressed on dam 24-h milk yield, and interactions of linear and quadratic regression coefficients with calf sire breed and postweaning treatment of calf were evaluated. In general, regression analyses indicated that calf postweaning ADG was linearly related to dam milk yield, but the relationships depended on the calf sire breed and postweaning treatment (P < 0.01). On dry-lot management, greater cow milk production was associated with lesser postweaning ADG in Gelbvieh- (P < 0.05) and Bonsmara-sired (P < 0.01) calves, whereas greater cow milk production was associated with greater postweaning ADG in Brangus-sired calves (P < 0.01), and a similar trend was observed in Charolais-sired (P < 0.19) calves. On wheat pasture management, greater cow milk production was associated with greater postweaning ADG in Gelbvieh-sired calves (P < 0.11), with a trend for greater cow milk production to be associated with lower postweaning ADG in Romosinuano-sired calves (P < 0.25). Results indicate that accurate determination of the relationship of dam milk production and calf postweaning ADG will require consideration of both calf postweaning management and calf sire breed.

Routers have the ability to output statistics about packets and flows of packets that traverse them. Passive traffic measurement increasingly employs sampling at the packet level. However, knowing the number and length of the original flows is necessary for some applications. This paper provides an algorithm that uses flow statistics formed from sampled packet stream to infer the absolute frequencies of lengths of flows in the unsampled stream. We achieve this through statistical inference and by exploiting heavy-tailed feather. We also investigate the impact on our results of different packet sampling rate. The theoretical analysis demonstrates that the computational complexity is well under control, and the experiment results show the inferred distributions are accurate in most cases.

It has frequently been observed that the ductility or elongation of a material can significantly be affected by its grain size. Poor ductility with low elongation has been found in ultrafine-grained (UFG) steels when their grain size is smaller than a critical value. The so called instability of plasticity is a well known drawback for UFG steels and has greatly prevented them from wider application. Although the instability has been attributed to the lack of strain hardening capacity of ultrafine-grained materials, its mechanism is still unclear. In this paper, a newly developed model for predicting the dependence of uniform elongation on grain size is described, using which the instability of plasticity in UFG steels can be explained. The model is based on a strain hardening model for polycrystalline metals that was previously developed by the present author and was modified in the present study to take the grain size effect into account. The uniform elongation calculated using the model is in good agreement with that experimentally measured in two steels. It was found that the elongation begins to decrease rapidly when the grain size is reduced to below 2μm - a clear sign of the occurrence of the instability of plasticity.

Particle acceleration by direct current electric field in the current sheet has been extensively studied, in which an electric and a magnetic field are generally prescribed, and a power law distribution of the electron energy is obtained. Based on MHD numerical simulations of flares, this paper aims at investigating the time evolution of the electron energy spectrum during solar flares. It turns out that the model reproduces the soft–hard–hard spectral feature which was observed in some flares.

Cooler Storage Ring (CSR) of Heavy Ion Research Facility in Lanzhou (HIRFL) consists of a main ring (CSRm) and an experimental ring (CSRe). Two particular C-type dipoles with embedded windings are used in the injection beam line of CSRm. They also act as the prototype dipoles of CSRe. The windings are designed to improve the field quality by their trimming current. The current impacts on field homogeneity and multipole components are investigated by a hall sensor and a long coil, respectively. The experiment shows that a field homogeneity of plusmn1.0times10-3 can be reached by adjusting the trimming currents, though the multipole components change correspondingly. In our case, the quadrupole component is decreased to a low level with the octupole, decapole and 12-pole ones increased slightly when the trimming current is optimized

The magnet design, fabrication, and measurement of HIRFL-CSR (Heavy Ion Research Facility in Lanzhou Cooling Storage Ring) are presented. All magnets will be laminated and welded with an armor-coated surface between two big endplates made of sticking glue 0.5 mm-thick sheets. The dipole of CSRm was chosen an H type with an air circle on the pole to improve the field uniformity. The dipole of CSRe was chosen the C type with an air circle and two air slots on the pole to improve the field homogeneity. Its reproducibility of magnet to magnet was adjusted with inserting small laminating pieces before demountable pole ends to reach less than plusmn2times10-4 at optimized field level. CSRm quadrupoles diameter is 170 mm and has two different lengths, and its endplates were made with punching pieces after coating with epoxy glue, there is chamfered directly on the pole ends to reduce 12th-order contribution of field and without the demountable pole ends. CSRe main quadrupoles diameter is 240 mm and has two different lengths, and its endplates were also made with punching pieces coated with epoxy glue, there is also chamfered directly on the pole ends to reduce 12th-order contribution of field like CSRm

The age hardening, stress corrosion cracking (SCC) and hydrogen embrittlement (HE) of an Al-Zn-Mg-Cu 7175 alloy were investigated experimentally. There were two peak-aged states during ageing. For ageing at 413 K, the strength of the second peak-aged state was slightly higher than that of the first one, whereas the SCC susceptibility was lower, indicating that it is possible to heat treat 7175 to high strength and simultaneously to have high SCC resistance. The SCC susceptibility increased with increasing Mg segregation at the grain boundaries. Hydrogen embrittlement (HE) increased with increased hydrogen charging and decreased with increasing ageing time for the same hydrogen charging conditions. Computer simulations were carried out of (a) the Mg grain boundary segregation using the embedded atom method and (b) the effect of Mg and H segregation on the grain boundary strength using a quasi-chemical approach. The simulations showed that (a) Mg grain boundary segregation in Al-Zn-Mg-Cu alloys is spontaneous, (b) Mg segregation decreases the grain boundary strength, and (c) H embrittles the grain boundary more seriously than does Mg. Therefore, the SCC mechanism of Al-Zn-Mg-Cu alloys is attributed to the combination of HE and Mg segregation induced grain boundary embrittlement.

In order to deal with dead-zone nonlinearity in the input function through variable structure control theory, a new robust decentralised control scheme is proposed for a class of uncertain large-scale interconnected dynamic systems. Dead-zone characteristics are quite commonly encountered in actuators, such as electric servomotors and electronic circuits. Therefore, in addition to the uncertainties in the system, one must also be concerned with dead-zone nonlinearity in controller design. The proposed variable structure controller ensures the global reaching condition of the sliding mode of the uncertain composite system in the presence of input dead-zone nonlinearity. Also, in the sliding mode, the investigated uncertain composite system remains insensitive to the uncertainties and disturbances, and behaves like a linear system. Furthermore, it is shown that the proposed control law can be applied to uncertain large-scale systems with and without input nonlinearities. Nevertheless, this cannot be guaranteed by the traditional variable structure control design for the systems without dead-zone nonlinearity. Illustrative examples are given to verify the validity of the developed controller.

The magnet in the beam line injection from a Separate Sector Cyclotron (SSC) to Cooling Storage Ring (CSR) was selected as CSR magnet fabrication's R&D. A method to obtain good field homogeneity was attempted in a C type dipole prototype. This method is not enlarged the dipole gap and need only two different very smaller power supply and easy operated and little cost. Because the C type dipole prototypes have a larger bending angle and smaller radius, it is very difficulty to stack and fabrication. The quadrupole prototype in the CSRm injection beam line is four fold assembly quadrupole. Its coils were made with a special vacuum epoxy impregnation technology, which is not necessary to use the complicated and expensive impregnating mold. Its maximum pole tip field was designed to reach near 10 000 Gs. All prototypes' fabrication and field measurement results will be present in detailed in this paper.

The magnet design choices and calculations for HIRFL-CSR (Heavy Ion Research Facility in Lanzhou Cooling Storage Ring) are presented. CSR desires the dipole magnet field uniformity B/B/sub 0/ /spl les/ /spl plusmn/10/sup -4/ and good field width reaching to /spl plusmn/ 70 mm and /spl plusmn/110 mm for the main ring and experimental ring respectively. For the dipole of CSRm, an H type was chosen with an air circle on the pole to improve the field homogeneity that was obtained with 2-D and 3-D code calculations. For CSRe, because the demand by the physics experiments, the dipole was chosen as C type. Many ideas were adopted to reduce its size, for it is very difficult to fabricate such a large laminated dipole in our country. All quadrupole lenses need field nonlinear gradient better than /spl plusmn/ 2 /spl times/ 10/sup -3/ in the good field region which width is 80 mm and /spl plusmn/ 140 mm for the main ring and experimental ring respectively. All magnets will be laminated of 0.5 mm-thick sheets of cold rolled electrical steel with an armor-coated surface.

The structure and magnetic properties of multilayer Co 82 Pt 18 /C films with equal CoPt and C layer thickness have been studied as a function of annealing temperature and film thickness. In general, annealing leads to the breakup of the continuous films and the formation of a laterally heterogeneous morphology consisting of separate CoPt and C regions. For individual layer thickness ⩾5.3 nm, annealing has no significant effect on the crystallographic structure and magnetic properties of the films. In both the as-deposited and annealed states, the films have HCP structure with perpendicular c -axis orientation and exhibit perpendicular magnetic anisotropy. The structure of these films appears to be associated with the growth of the CoPt on the C layers. For films with individual layer thickness of 1.3 and 2.7 nm, the structure and magnetic properties are strongly affected by annealing. In the as-deposited state, films have a fine grain structure and coercivities of a few Oe. Annealing leads to the breakup of the multilayer structure at about 300°C and the formation of ∼20 nm HCP and FCC magnetic grains, with the HCP grains exhibiting in-plane c -axis texture. Annealed films have large in-plane coercivities (maximum of 2.77 kOe) and random in-plane magnetic anisotropy. The increase in coercivity with annealing temperature above ∼375°C is primarily associated with an increase in switching volume.

Different morphologies of zinc oxide (ZnO) nanorods and nanotubes, which were grown under the same conditions but different dissolving processes, are prepared in our experiment through hydrothermal method. After the growth process, cooling down the reactor naturally or dissolving at a constant temperature of 40 °C, preferential dissolution will occur at different places on the tip of ZnO nanorods. During the dissolution process, different dissolution rates on the entire surface of nanorod will lead to different nanostructures. ZnO nanorods and nanotubes on Cu substrates display the same PL property with strong green emission but weak UV emission, while ZnO nanorods on Si substrates exhibits a relatively strong UV emission.

The objective of this paper is to explore the synergistic combination of coagulation with biological processes for drinking water treatment on the basis of on‐site biofilters and jar tests. Three raw water sources in China were tested. Zeta potential was chosen as a major parameter. Experimental results indicated that biological processes can result in significant change of zeta potential of water flow, making the zeta potential of effluent less negative than that of raw water. The observation of biofilm morphology with scanning electronic microscope showed that the biofilm is in the shape of a cobweb and can hold a large number of turbidity particles. The combination of biotreatment with coagulation can enhance process efficiency and save coagulant significantly. Results in this paper suggested that further explorations are needed to determine the best support medium for biofilm growth and the best combination of coagulation with biotreatment in different situations.

A unified theoretical model for work-hardening of polycrystalline metals has been developed by considering the effect of dislocation structure formation on dislocation storage and dynamic recovery rates during deformation. The model consists of two structural parameters: a factor of mean dislocation number associated with a dislocation-band-site at the steady state of deformation, in addition to another more conventional parameter, the mean dislocation density or flow stress. The model can be applied to a wide range of deformation conditions and the two well known work-hardening laws, i.e. the Kocks model suitable for low temperature deformation and Roberts model has been validated by using reported derived directly from the unified model as special cases. The model has been validated by using reported experimental data for high purity aluminum. Good agreement has been obtained between the theory and the measurements.

Recently, ZnO-based semiconductors have been attracting increasing attention as promising candidates for optoelectronic applications in ultraviolet (UV) regions [1,2]. Because ZnO has a very large exciton binding energy (60 meV), it allows ef‹cient excitonic emission at high temperature [3]. As is well known, an exciton-related lasing process can easily achieve higher gain and lower threshold, ZnO desirable to develop optoelectronic devices based on excitonic effect. In addition, in order to obtain high-performance light-emitting diode (LED) devices, one of the key techniques is to construct a heterojunction to realize double con‹nement actions for electrons and photons in optoelectronic devices. Because the ionic radius of Mg2+ (0.57 A) is close to that of Zn2+ (0.6 A), MgxZn1−xO alloy is considered to be a suitable potential barrier material by doping Mg as a substitute for Zn2+ ion in ZnO [4,5]. However, ZnO and MgO belong to wurtzite structure and rocksalt structure, respectively. The difference between ZnO and MgO with regard to their thermally stable structure results in phase separation of MgxZn1−xO at high Mg composition. It is suggested that the Mg content of x = 0.33 is the solubility limit of MgxZn1−xO thin ‹lms for the wurtzite structure [7]. Hence, the main researches are concentrated on the growth andCONTENTS9.1 Introduction 223 9.2 Experimental 2269.2.1 Materials Growth 226 9.2.2 Characterization Techniques 227

The absence of experimental neutron reactors, safe hot-cell testing environments, and sufficient time and funding encourage the use of ion-irradiation simulation to study the behavior of fission and fusion materials. It was observed that ion induced preferential sputtering phenomenon occurs in some ion-implanted and -simulated studies. No detailed discussion has been presented, however, concerning the effects of the preferential sputtering phenomenon, such as phase transform (fcc[r arrow]bcc) and its influences, initiating intergranular cracks in slow strain rate tensile (SSRT) testing, TEM specimen preparation difficulties, and so on. Therefore, the objective of this research is to investigate the preferential sputtering phenomenon and its influences on the SSRT of commercial purity AISI 304 austenitic stainless steel. The preferential sputtering (the grain boundary etching and surface slip bands) phenomenon occurred during H[sup +] and Ni[sup +2] ion-irradiation. It was found that the degree of preferential sputtering increased as the fluence increased. It was found that the ion-induced preferential sputtering phenomenon would cause both difficulties in preparing the TEM specimens and the initiating of intergranular cracks. Simultaneously, preferential sputtering would affect the amount of intergranular surface cracking in SSRT tests.

Radiation-enhanced and -induced phases precipitation, radiation-induced solute segregation and radiation-induced preferential sputtering have been observed in the irradiated stainless steels. Austenite([gamma]) to ferrite([alpha]) phase transformation has been reported in austenitic stainless steels following neutron- and ion-irradiation, long-term thermal aging and mechanical deformation. Irradiation-assisted stress corrosion cracking (IASCC) has recently become an important issue related to cracking of in-core components in Light Water Reactors (LWR's). It therefore leads to a possibility that the IASCC susceptibility may be related to the austenite stability of stainless steel. The lacks of neutron irradiation environments, preparation and testing equipment, and sufficient time and expense force the use of ion-irradiating simulation experiments for fission and fusion materials research and development. The purpose of this study is to investigate the proton irradiation-induced phase transformation ([gamma][yields][alpha]) phenomenon in commercial purity AISI 304L austenitic stainless steel and the influences on its intergranular stress corrosion cracking (IGSCC) susceptibility.

High performance Resistive Random Access Memory (RRAM) based on HfOx has been prepared and its temperature instability has been investigated in this work. With increasing temperature, it is found that: leakage current at high resistance state increases, which can be explained by the higher density of traps inside dielectrics (related to trap-assistant tunneling), leading to a smaller On/Off ratio; set and reset voltages decrease, which may be attributed to the higher oxygen ion mobility, in addition to the reduced potential barrier to create / recover oxygen ions (or oxygen vacancies); temperature impact on the RRAM retention degradation is more serious than electrical bias., {"references":["G. Baek, D. C. Kim, M. J. Lee, H. J. Kim, E. K. Yim, M. S. Lee, J. E.\nLee, S. E. Ahn, S. Seo, J. H. Lee, J. C. Park, Y. K. Cha, S. O. Park, H. S.\nKim, I. K. Yoo, U. I. Chung, J. T. Moon, and B. I. Ryu, \"Multi-layer\ncross-point binary oxide resistive memory (OxRRAM) for post-NAND\nstorage application,\" in IEDM Tech. Dig., 2005, pp. 750-753.","D. C. Kim, S. Seo, S. E. Ahn, D. S. Suh, M. J. Lee, B. H. Park, I. K. Yoo,\nI. G. Baek, H. J. Kim, E. K. Yim, J. E. Lee, S. O. Park, H. S. Kim, U. I.\nChung, J. T. Moon, and B. I. Ryu, \"Electrical observations of\nfilamentary conductions for the resistive memory switching in NiO\nfilms,\" Appl. Phys. Lett., vol. 88, p. 202102, May 2006.","D. B. Strukov, G. S. Snider, D. R. Stewart, and R. S. Williams, \"The\nmissing memristor found,\" Nature, vol. 453, pp. 80-83, May 2008.","R. Dong, D. S. Lee, W. F. Xiang, S. J. Oh, D. J. Seong, S. H. Heo, H. J.\nChoi, M. J. Kwon, S. N. Seo, M. B. Pyun, M. Hasan, and H. Hwang,\n\"Reproducible hysteresis and resistive switching in metal- Cux O -metal\nheterostructures,\" Appl. Phys. Lett., vol. 90, p. 042107, Jan 2007.","H. Y. Lee, P. S. Chen, T. Y. Wu, Y. S. Chen, C. C. Wang, P. J. Tzeng, C.\nH. Lin, F. Chen, C. H. Lien, and M. J. Tsai, \"Low power and high speed\nbipolar switching with a thin reactive ti buffer layer in robust HfO2\nbased RRAM,\" in IEDM Tech. Dig., 2008, pp. 297-300.","N. Xu, B. Gao, L. F. Liu, B. Sun, X. Y. Liu, R. Q. Han, J. F. Kang, and\nB. Yu, \"A unified physical model of switching behavior in oxide-based\nRRAM,\" in VLSI Symp., 2008, pp. 100-101.","C. Kittel, \"Introduction to solid state physics (8th ed),\" pp. 585-591.","R. Meyer, L. Schloss, J. Brewer, R. Lambertson, W. Kinney, J. Sanchez,\nand D. Rinerson, \"Oxide dual-layer memory element for scalable nonvolatile\ncross-point memory technology,\" in NVMTS Proc., 2008, pp. 1-\n5"]}