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A continuous stirred tank reactor (CSTR) was operated for more than 120 days with fixed hydraulic retention time of 6 h at mesophilic temperature along with a periodic recovery phase towards hydrogen production and stimulated by the existence of 5-hydroxy methyl furfural concentration (5-HMF). Interestingly, CSTR mixed with a small amount of 5-HMF, range of 0.3–0.6 g/L showed at least 50% higher hydrogen production rate than control without 5-HMF. However, when 5-HMF concentration was higher than 0.6 g/L, the performance was significantly inhibited. The bacterial community shifted by 5-HMF from Clostridium-dominated to Lactobacillus-dominated population. Regardless of the remain 5-HMF concentration in CSTR, the microbial community and hydrogen producing performance were restored by stop mixing the 5-HMF from the feedstock. The high-rate hydrogen production of 20.0 ± 1.8 L H2/L/d was achieved in the presence of 5-HMF using the threshold information and recovery strategy.

Magnetic properties and microstructure of Sm(Co0.647Fe0.28Cu0.053Zr0.02)7.84 magnets prepared by HD powder with different residual hydrogen content (25, 715, 1512 ppm) have been investigated. The squareness and coercivity increase from 0.56 to 0.63 and 24.03 to 26.37 kOe as the hydrogen content increased from 25 to 1512 ppm. TEM results show that similar cellular structure and lamellar structures are formed in these magnets. Due to superabundant vacancies induced by hydrogen, the average grain size of final magnets increases from 50.22 to 62.29 μm with the increase of hydrogen in HD powder. Larger grain size results in fewer grain boundary areas where no clear cellular structure formed. The kerr observation indicate that the reversal domain formed at the grain boundary areas is easier to grow up, while the reversal of in-grain domain shows much harder.

We present a novel design for a wavelength-switchable nanosecond-pulsed erbium-doped fiber laser that simultaneously achieves a repetition rate of the order of hundreds of kilohertz as well as pulse energies in the hundred-nanojoule range to fulfil the requirements of photoacoustic (PA) imaging applications. Instead of conventional Q-switching of a single-wavelength output, rapid switching among multi-wavelength outputs in the 1600 nm region can be performed by tuning acousto-optic modulation frequencies under low-order active mode-locking conditions. The pulse repetition rate of the laser can be tuned from 200 kHz to 1 MHz, depending on the mode-locking order. In order to verify the potential of our proposed design for use in real-time PA applications, we detected PA signals generated by an absorbing target using a PA signal detection system with our dual-wavelength laser outputs.

Grain boundary modification induced giant coercivity enhancement from 945 kA/m to 1904 kA/m was achieved in Sm25Co48Fe20Cu5Zr2 magnets by doping 0.4 wt% CuO. Different magnetization reversal behaviors were clearly observed between un-doped and doped magnets. Compared with un-doped magnets, Cu enrichment along grain boundary promoting regular cellular structure was obviously found in doped magnet. The in-situ Kerr observation indicated that complete cellular structure could strengthen the pinning field of grain boundary regions and the propagations of magnetization reversals into interiors of grains were restrained by the modified grain boundaries, which resulted in the remarkable coercivity increment.

Film cooling techniques have been widely applied to gas turbine engines to protect the components from hot combustion gas. In this study, the shape of the laidback fan-shaped hole with a lateral expansion angle of 10 degrees was optimized through the Reynolds Averaged Navier-Stokes (RANS) analysis. Results by numerical analysis were validated with the corresponding experimental results obtained by the pressure sensitive paint technique (PSP). For optimal hole shape derivation, the design points were selected through the Latin Hypercube Sampling (LHS) method for three design variables: injection angle, metering length, and forward expansion angle. The overall averaged effectiveness was used as the objective function. Results showed that the overall film cooling effectiveness of the optimal holes derived by the response surface method and the Kriging method were higher than that of the reference hole by 4.5% and 7.5%, respectively. Generally, holes with a higher area ratio (AR) showed higher overall film cooling effectiveness. However, the interaction between each shape parameter should be considered to derive the optimal hole shape.

Spin-reorientation-transition cell boundary phases are used to improve the temperature stability of coercivity in 2:17 type SmCo magnets. A magnet with both low temperature coefficients of remanence (α) and coercivity (β) is developed. In comparison with traditional 2:17 type SmCo magnets with low temperature coefficient of remanence, this magnet exhibits comparable (BH)max and α, meanwhile the β(20–100 °C) is improved by more than two orders of magnitude. The comparative study of reversible magnetization/irreversible magnetizations indicates that the flux losses of this magnet are barely affected by temperature, which is an remarkable improvement in developing temperature-stable magnet.

Environmental sampling is a critical component of the post decontamination verification process following a bioterrorism event. The current work was performed to produce a less labor-intensive method for processing cellulose sponge-wipes used for sampling areas potentially contaminated with low concentrations (i.e., post-decontamination) of Bacillus anthracis spores . An alternative fast-analysis processing method was compared to the processing protocol validated by the Centers for Disease Control and Prevention (CDC) for the Laboratory Response Network (LRN). Glazed tile coupons (1102 cm 2) were inoculated with 50, 500, or 5000 spores of Bacillus thuringiensis subsp. kurstaki (Btk), then sampled with cellulose sponges. Sampling was limited to a 25- by 25-cm area and performed in the same manner as the CDC sampling method. Samples were then processed using either the alternative “Fast Analysis” method or the “CDC method”. Three different analysts repeated the tests at each concentration utilizing each method. Mean recoveries, labor time, and potentially hazardous waste produced were compared for the two methods. The mean percent recoveries and standard errors for the samples processed using the “CDC method” were 39.9 ± 6.7, 43 ± 7.6, and 36.8 ± 10.1 for the 5000, 500, and 50 spore loading levels, respectively; compared to 54.2 ± 12.9, 64.2 ± 21.7, and 45.2 ± 8.6 for the “Fast Analysis” method. At each titer tested the “Fast Analysis” method resulted in a statistically significant higher percent recovery. Furthermore, analysts processed samples utilizing the “Fast Analysis” method in less than half the time and generated half as much potentially hazardous waste compared to the “CDC method”.

The high-coercivity Nd-Fe-B magnets with “core-shell” structure grains were prepared by doping TbCu powders and hot pressing after pre-sintering in the traditional powder metallurgy process. The coercivity for the hot-pressed pretreated Nd-Fe-B magnet is obviously enhanced to 28.6 kOe from 24.3 kOe by TbCu alloy doping. The Tb contents at the shell structure of grain in the hot-pressed pretreated magnet is 5.7 wt% while that in the dual-alloy magnet is 3.0 wt%. The enrichment of Tb elements in the shell layer further enhances the anisotropy of the grain surface and effectively improves the utilization efficiency of heavy rare earths. The existence of the hard (Tb, Nd)2Fe14B shell, which can effectively inhibit the reverse nucleation of magnetic domains, contribute to enhance the coercivity with few reduction of the remanence. Compared with the grain boundary diffusion process, this technology can be used to prepare large pieces of high performance Nd-Fe-B bulk magnets without diffusion depth limit.

A three-dimensional (3D) multiphase Eulerian computational fluid dynamics (CFD) model was developed to investigate the effect of a simultaneous three-angular motion (roll, yaw and pitch) on the performance of an air-water-oil separator. The dynamic mesh method with a 3D rotational matrix was used to simulate the three-phase separator under simultaneous three-angular motion. The pressures at water and oil outlets were adjusted by a user-defined function based on a proportional control algorithm. The CFD model was validated against experimental free oscillations of an immiscible two-fluid system under a pitching motion. The simultaneous three-angular motion with an amplitude 2° and a period of 8 s showed an oil purity of 98% and an oil recovery of 99%, which were comparable to those of the onshore separator. However, the 4° simultaneous three-angular motion deteriorated the oil recovery to 92% and the water purity to 75%. As the separation performance of the pitching motion was similar to that of the simultaneous three-angular motion, the performance of the three-phase separator can be tested simply by the pitching motion.

A three-phase transient Eulerian computational fluid dynamics (CFD) model was developed to investigate the effect of three angular motions (rolling, yawing, and pitching) on the separation efficiency of an air–water–oil separator. The horizontal cylindrical separator included a feed inlet, a gravity separation zone with a coalescer for water and oil separation, and a mist elimination zone. The CFD model consisted of the continuity, momentum, and standard k-e turbulence equations. The CFD equations were solved in a moving reference frame to take into account the angular motions. The exit pressures at the water and oil outlets were controlled using a user-defined function since the CFD model without pressure control resulted in backflow from the water outlet, which was not realistic. CFD cases, such as no motion, rolling, yawing, 2° pitching, and 4° pitching with a period of 8 s were simulated with exit pressure control. The angular motions with pressure control showed a stable cyclic behavior with a high oil separation efficiency. However, the 4° pitching motion decreased the oil recovery to 93% with 77% water purity at the water outlet.

Low-melting eutectic diffusion has emerged as a practical approach to enhance the coercivity of hot-deformed Nd–Fe–B magnets. Herein, we report a high-efficient stress-induced eutectic diffusion method to develop high-coercivity hot-deformed Nd–Fe–B magnets. In this method, fast Pr–Cu eutectic diffusion is accomplished with the hot-pressed and hot-deformed processes simultaneously. The coercivity of diffusion-processed magnets is substantially increased by about 33% with a slight remanence loss. The applied stress effectively controls the distribution of Pr–Cu eutectic and relieves the remanence loss. Microstructure analysis confirms that the Pr–Cu concentration gradient constructed in hot-pressed precursors effectively suppresses the near-surface grain growth during the hot-deformation process and reduces the lateral/longitudinal ratio of platelet-shaped grains. The formation of thick and continuous Pr-rich grain boundaries weakens the exchange coupling between neighboring grains, offering more “pinning” sites for domain wall displacement. Partially Pr-substitution improves the locally magnetically “hardening” of 2:14:1 main phases. The optimized structural and magnetic characterizations hinder the nucleation and propagation of reversed magnetic domains at low magnetic fields, which is beneficial to coercivity enhancement. These findings clarify the characteristics of the stress-induced diffusion method and give a new insight into the structural modulation for Nd–Fe–B materials.

Balanced usages of the high-abundance rare-earth elements, such as La, Ce and Y, have attracted tremendous interests of the industrial and scientific societies because of the economic and environmental merits. One of the key issues is of understanding the whole process metallurgical behavior of the high-abundance rare-earth elements in order to optimize the microstructures for a high magnetic performance of the RE-Fe-B sintered magnets, which contain a high concentration of the high-abundance rare-earth elements. In this work, we systematically characterized the metallurgical behaviors during the whole process of strip casting, sintering and annealing for the magnets (Nd0.75LRE0.25)30.5FebalAl0.1Cu0.1B1 (LRE = La, Ce and Y, wt. %). During the strip casting (SC), La and Ce mainly distribute in the grain boundary phase while Y distributes uniformly in the 2:14:1 matrix phase grains. Under the sintering and annealing, La is squeezed out from the 2:14:1 matrix phase to segregate in the grain boundaries, while Ce and Y migrate from the grain boundary to the 2:14:1 matrix phase. The crystalline structures of matrix phase and grain boundary phase of Nd-La/Ce/Y-Fe-B are tetragonal phase (space group P42/mnm) and hcp-Re2O3. The investigations of the grain boundary of Nd-La/Ce/Y-Fe-B magnets demonstrate that the grain boundary of the magnet with Ce is thicker than that of magnets with La and Y. The different metallurgical behaviors of elements La, Ce and Y are attributed to the different solidification temperature and substitution energy of Re2Fe14B phases. Core-shell grain structure was formed in the case of Y-containing magnets. Elemental analysis demonstrates that Y prefers to locate in the core of the grain boundary and Nd distributes in the shell of the grain boundary.

The effects of Ho substitution for Nd on the microstructure, corrosion resistance and thermal stability of the Nd-Fe-B magnets were investigated. The (Nd,Ho)-O phase was formed with increasing Ho substitution. The results of potentiodynamic polarization and highly accelerated stress test show improved corrosion resistance with increasing Ho substitution. The optimum mass loss 0.29 mg/cm2 is achieved. Moreover, the average temperature coefficients for remanence and coercivity in the range of 25–150 °C are both closer to zero, indicating improved thermal stability. The mechanisms for the improved corrosion resistance and thermal stability are discussed in relation to the microstructure featuring the (Nd,Ho)-O phase.

In this work, the effect of Zr content on magnetic properties and electrical resistivity of Sm(CobalFe0.09Cu0.09Zrx)7.68 (x = 0.020, 0.025, 0.030, 0.035) high temperature magnets has been investigated. More Zr content results in the decrease of average cell size and the increase of the density of lamellar structure. In addition, a large number of phase boundaries between lamellar phase and cellular structure have also been formed. The intrinsic coercivity of 550 °C enhances from 3.21 kOe to 6.05 kOe with the increase of Zr content. Furthermore, electrical resistivity shows obviously different variation in different directions with increasing Zr content. At room temperature and 127 °C, the electrical resistivity improves from 68.2 μΩ cm to 91.7 μΩ cm and from 87.1 μΩ cm to 103.3 μΩ cm with increasing x from 0.020 to 0.035 in the direction parallel to c-axis, respectively. However, there is only a slight increase in the electrical resistivity in the direction perpendicular to c-axis. The rise of electrical resistivity in different directions has been discussed. Research results indicate that increasing the density of the lamellar phase is an effective way to increase electrical resistivity in the 2:17-type Sm-Co magnets.

Objectives To assess Asian data from Global Prevalence Study on Infections in Urology (GPIU study) which has been performed more than 10 years. Methods Seventeen Asian countries participated in the GPIU study between 2004 and 2013. Data for these countries were collected from the web-based GPIU database. The point prevalence of urinary tract infections (UTI) and antimicrobial susceptibility of representative pathogens were analysed for Asian geographic regions. Results A total of 6706 patients (5271 male, 1435 female) were assessed during the study period, and 659 patients were diagnosed with a UTI (9.8%). Of these UTI patients, 436 were male and 223 were female. Mean patient age was 54.9 ± 19.3 years. Pyelonephritis and cystitis were the most common clinical diagnoses, representing 30.7% and 29.9% of patients, respectively. Escherichia coli was the most frequently identified uropathogen (38.7%). For the patients with urinary tract infection, cephalosporins were the most frequently used antibiotics (34.4%), followed by fluoroquinolones (24.1%), aminoglycosides (16.8%). Fluoroquinolone resistance was relatively high (ciprofloxacin 54.9%, levofloxacin 39.0%), and cephalosporin resistance 42% (42.5–49.4%). Of the antibiotics evaluated, uropathogens had maintained the highest level of susceptibility to amikacin and imipenem (24.9% and 11.3% resistance rates, respectively). Conclusion Uropathogens in many Asian countries had high resistance to broad-spectrum antibiotics. Knowledge of regional and local resistance data and prudent use of antibiotics are important for proper management of UTI in Asian countries.

The anisotropic hot deformed magnets consisting of Nd-rich and Ce-rich 2:14:1 main phases were prepared using dual alloy process. After heat treatment, crystallographic alignment was improved and compositional heterogeneity reduced. Coercivity and remanence descended with increasing Ce-Fe-B addition, and then were improved after diffusing heat treatment compared with magnets without heat treatment. Moreover, the magnetization behaviors of magnets were discussed and the coercivity mechanism was controlled by inhomogeneity of the domain wall pinning. The interaction domains were observed and the moment of Ce-rich grain was prior to reversal by comparison with Nd-rich grain in an applied field due to the lower magnetocrystalline anisotropy.

Thermal stability of coercivity and domain structure in sintered Nd–Fe–B magnets with various grain sizes has been studied. Microstructure analysis shows that the improved thermal stability arises from the grain morphology beneficial to a small effective demagnetization factor Neff. In-situ magnetic domain evolution during thermal demagnetization indicates that lower surface stray field in fine-grained magnets suppresses the reversion of domain in high temperature condition, which results from temperature-dependent competition between the local demagnetizing field and effective anisotropy field of surface grains.

In this study, we presented an effective approach for the substantial coercivity enhancement of Dy-free sintered Nd-Fe-B magnets with Ga-doping. The coercivity was substantially enhanced from 10.1 kOe to 19.8 kOe by effective microstructure optimization and phase constitution regulation in antecedent alloys. A good isolation of 2:14:1 grains by Nd-rich intergranular phase is obtained in final magnets accompanying with the formation of intermetallic Nd6Fe13Ga phase. However, when dehydrogenating above 500 °C, masses of preformed Nd6Fe13Ga phases are detected in the initial strip casting alloys and the homologous magnet suffers an unanticipated degradation of coercivity. Magnetic domain observation and thermal magnetic analysis imply a pronounced difference in the magnetism of grain boundary (GB) phases, which closely associated with the composition homogeneity of Nd-rich phases in antecedent alloys. The mechanism of the coercivity variation in the sintered magnets with different GBs magnetism is discussed based on magnetic behavior analysis.

High coercivity of hot-deformed Nd 2 Fe 14 B magnets was obtained by grain boundary diffusion. Comparable squareness and similar magnetic properties for samples diffusing from side and pole surfaces show little discrepancies if quantities of the infiltrated PrNd-Cu low eutectic alloys is enough to obtain sufficient diffusion. However, the microstructures and higher characteristic peak ratios show preferable orientation of grains near surfaces of the sample diffused from side surfaces than that from pole surfaces. Amorphous Nd-rich phases and crystal Fe-rich phases were both observed in the diffused magnets. The enhancement of coercivity is considered to be resulted from grain boundary optimization and magnetic isolation which is caused by the thickened nonmagnetic intergranular phases.

Radiological release incidents can potentially contaminate widespread areas with radioactive materials and de-contamination efforts are typically focused on populated areas, which means radionuclides may be left in forested areas for long periods of time. Large wildfires in contaminated forested areas have the potential to reintroduce these radionuclides into the atmosphere and cause exposure to first responders and downwind communities. One important radionuclide contaminant released from radiological incidents is radiocesium ((137)Cs) due to high yields and its long half-life of 30.2 years. An Eulerian 3D photochemical transport model was used to estimate potential ambient impacts of (137)Cs re-emission due to wildfire following hypothetical radiological release scenarios. The Community Multiscale Air Quality (CMAQ) model did well at predicting levels and periods of increased PM2.5 carbon due to wildfire smoke at routine surface monitors in California during the summer of 2016. The model also did well at capturing the extent of the surface mixing layer compared to aerosol lidar measurements. Emissions from a large hypothetical wildfire were introduced into the wildland-urban interface (WUI) impacted by a hypothetical radiological release event. While ambient concentrations tended to be highest near the fire, the highest population committed effective dose equivalent by inhalation to an adult from (137)Cs over an hour was downwind where wind flows moved smoke to high population areas. Seasonal variations in meteorology (wind flows) can result in differential population impacts even in the same metropolitan area. Modeled post-incident ambient levels of (137)Cs both near these wildfires and further downwind in nearby urban areas were well below levels that would necessitate population evacuation or warrant other protective action recommendations such as shelter-in-place. These results suggest that 1) the modeling system captures local to regional scale transport and levels of PM2.5 from wildfire and 2) first responders and downwind population would not be expected to be at elevated risk from the initial inhalathion exposure of (137)Cs re-emission.

Anisotropic Nd-Fe-B magnets with WC addition were prepared by hot deformation process. The effect of WC addition on the compressive and bending strength of hot-deformed Nd-Fe-B magnets has been investigated. The results suggest that the mechanical properties of hot-deformed magnets without WC addition show distinct anisotropy. Meanwhile, WC addition lowers the mechanical anisotropy in two directions parallel and perpendicular to c-axis, especially the compressive strength. The optimum mechanical properties are obtained at 1.0 wt % WC addition without sacrificing the magnetic properties. The observation for microstructure reveals that the fracture mechanism of hot-deformed magnets is a typical intergranular fracture and the crack is prior to propagate along the ribbon boundary. The improved mechanical properties might be attributed to both the grain refinement at ribbon boundaries and the reinforced effect of WC addition.

The coercivity of sintered Nd-Fe-Cu-B magnets is markedly enhanced from 12.57 to 21.70 kOe while the remanence decreases from 13.80 to 13.49 kGs by grain boundary diffusion of TbF3 powder for 2 h. Microstructure analysis suggests that, during the diffusion process, F diffuses into the magnets easily and forms a new F-rich phase. The enrichment of F in grain boundary near the surface leads to the Cu movement into the interior and the Cu reduction in the surface of magnets. Diffusion of Tb leads to an increase of local total rare earth elements content. Under the combined effect of Cu reduction and increase of local total rare earth elements content, grain growth area is formed and further diffusion is suppressed. That excessive Tb diffuses into matrix phase leads to a decrease in remanence. When the grain growth area is removed, the deterioration of remanence recovers to 13.80 kGs without any reduction of coercivity.

High performance (La, Ce, Pr, Nd)-Fe-B anisotropic nanocrystalline magnets were fabricated through die-upsetting process by incorporating misch-metal in Nd-Fe-B magnets via dual alloy method. Although coercivity decrease with the increase of misch-metal monotonously, there are no significant decrease in remanence. Magnet with remanence of 13.46 kGs and maximum energy product of 43.5 MGOe was obtained with 30 wt% misch-metal substitution, which is quite promising in practical application. High remanence was resulted from good texture and microstructure analysis revealed that Ce tended to diffuse into 2:14:1 phase uniformly, while the excessive La tended to assemble into the interface of melt-spun ribbons.

HDDR processed Nd-Fe-B powders blended with Nd-Cu powders were hot-pressed and then hot-deformed to obtain fully dense, anisotropic magnets. The microstructure evolution in hot-pressed and hot-deformed HDDR magnets was studied to illustrate the impact of Nd-Cu diffusion on coercivity and deformation ability. It was found that the coercivity and the deformation ability were improved significantly by Nd-Cu addition. The coercivity of hot-deformed magnets was increased from 3.81 kOe to 13.01 kOe after 2 wt% Nd-Cu additions and the annealing at 900 °C for 2 h. Scanning electron microscopy and transmission electron microscopy observations revealed that the variation in coercivity was attributed to the diffusion of Nd-Cu along the grain boundaries during hot pressing and hot deformation.

A Dy-Cu eutectic injection process accompanying by hot deformation had the potential to fabricate the high-performance die-upset magnets. The good fluidity of Dy-Cu eutectic liquid accelerated the formation of near-surface texture and suppressed largely the grain growth during subsequent heat treatment. By the high-temperature microstructure evolution, the maximum energy product of injected magnets was substantially increased by 17.8%, from 45 to 53 MGOe. The near-surface microstructure of injected magnets was studied to clarify the effect of inhomogeneous Dy-Cu distribution on the texture and grain size.

Anisotropic ultrafine-grained Nd-Fe-B magnets with WC addition were prepared by hot deformation. With WC nano-particles addition of ~ 1.0 wt.%, the squareness was optimized and the coercivity of the hot-deformed magnets increased substantially by 2.16 kOe, from 15.59 to 17.75 kOe without expense of the remanent magnetization. The observation for microstructure revealed that the WC nano-particles mainly existed on the interfaces of melt-spun ribbons. Meanwhile, due to the local compressive stress induced by the hard WC nano-particles, the deformability of neighboring grains was remarkably enhanced which leads to the reduction of the coarse grain regions.

Ce-Fe-B sintered magnets with enhanced coercivity were prepared by the powder metallurgy method. The mechanism of the coercivity enhancement in Ce-Fe-B sintered magnets with the low-melting point intergranular additive was discussed in details. It was speculated that the low coercivity of Ce-Fe-B sintered magnet was related to the irregular sharps and relatively low magneto-anisotropy field of the matrix phase. After introducing a 20 wt.% Nd-based intergranular additive, the coercivity markedly increased from 108 Oe to 2560 Oe due to the formation of thin and continuous grain boundary layers and the surface modification of the matrix phase grains. Additionally, the formation of the high anisotropy field (Nd,Ce) 2 Fe 14 B shell was beneficial to the increase of the coercivity as well. This work suggested that adding low-melting point intergranular additives was effective to fabricate the practical Ce-Fe-B sintered magnets.

A dual-alloy method was applied to tune the distribution of Ce for enhancing the performance of Nd-Ce-Fe-B sintered magnets with a nominal composition of (Nd 0.75 Ce 0.25 ) 30.5 Fe bal Al 0.1 Cu 0.1 B. In comparison to the single alloy of (Nd 0.75 Ce 0.25 ) 30.5 Fe bal Al 0.1 Cu 0.1 B, the coercivity was enhanced from 10.3 kOe to 12.1 kOe and the remanence was increased from 13.1 kG to 13.3 kG for the magnets with a dual-alloy method. In addition, the remanence temperature coefficient α and coercivity temperature coefficient β were also slightly improved for the magnet with the dual alloys. The results of microstructure characterizations show the uniform distribution of Ce for the magnet with a single alloy, and the coexistence of the Ce-rich and Ce-lean regions for the magnet with the dual alloys. In combinations with the nucleation of reversal domains and magnetic recoil curves, the property enhancement of magnets with a dual-alloy method was well explained.

Nuclear or radiological terrorism in the form of uncontrolled radioactive contamination presents a unique challenge in the field of nuclear decontamination. Potential targets require an immediate decontamination response, or mitigation plan to limit the social and economic impact. To date, experience with urban decontamination of building materials - specifically hard, porous, external surfaces - is limited to nuclear weapon fallout and nuclear reactor accidents. Methods are lacking for performing wide-area decontamination in an urban environment so that in all release scenarios the area may be re-occupied without evaluation and/or restriction. Also lacking is experience in developing mitigation strategies, that is, methods of mitigating contamination and its resultant radiation dose in key areas during the immediate aftermath of an event and after lifesaving operations. To date, the tremendous strategy development effort primarily by the European community has focused on the recovery phase, which extends years beyond the release event. In this review, we summarize the methods and data collected over the past 70 years in the field of hard, external surface decontamination of radionuclide contaminations, with emphasis on methods suitable for response to radiological dispersal devices and their potentially unique physico-chemical characteristics. This review concludes that although a tremendous amount of work has been completed primarily by the European Community (EU) and the United Kingdom (UK), the few studies existing on each technique permit only very preliminary estimates of decontamination factors for various building materials and methods and extrapolation of those values for use in environments outside the EU and UK. This data shortage prevents us from developing an effective and detailed mitigation response plan and remediation effort. Perhaps most importantly, while the data available does include valuable information on the practical aspects of performing the various remediation methods including costs, coverage rates, manpower, pitfalls, etc., it lacks the details on lessons learned, best practices, and standard procedures, for instance, that would be required to develop a mitigation strategy. While the urban decontamination problem is difficult and there is much more research to do, the existing literature provides a framework for a response plan. Using this framework, in conjunction with computer modeling and relevant data collection, can lead to development of appropriate plans and exercises that would permit development of a mitigation and remediation response.

Two kinds of lamella phases were observed in the phase transformations during aging of Sm(Co 0.695 Fe 0.2 Cu 0.08 Zr 0.025 ) 7.2 magnets, which formed before and after the disappearance of microtwins respectively. Microtwins appeared with the precipitation of disordered 2:17R phases and disappeared with 2:17R phase ordering. Dy was introduced to investigate these transformations by stabilizing the 2:17H phases. A simplified atomic model was given to describe the formation of microtwins and a reasonable assumption was proposed as well to clarify the mechanism of these transformations.

The electroplating pretreatment of NdFeB magnets was simulated in this study, and the effect of the pickling process on element, matrix morphology and texture was discussed. The results showed that in the ordinary circumstance the acid solution concentration should be below 4 mol/L and the pickling time was within 120 s. However the concentration was lower than 1 mol/L and the time was about 30 s in the ultrasonic environment. The precoating technology sequentially was studied. The results revealed that there were two main reactions of the corrosion and displacement in the precoating process, and these two reactions were more obvious in the grain boundary. The electrochemical analysis illustrated that the corrosion and displacement reactions were affected obviously by the current density and the precoating solution temperature, usually the current density was controlled about 0.3 A/dm 2 , and the temperature was about 318 K in the precoating process.

Speciation and kinetics of carbon dioxide absorption by N-methylcyclohexylamine (MCHA) and 2,6-dimethylpiperidine (DMPD) emulsion absorbents were evaluated. The physical solubility, diffusivity, and carbon dioxide absorption rate were measured as a function of temperature (293, 303, 313, and 323 K) and amine concentration (10, 20, 30, and 40 wt%) by using a semibatch reactor and wetted wall column (WWC). The results showed that the rate of carbon dioxide absorption by the MCHA and DMPD emulsion absorbents increased with the carbon dioxide partial pressure and amine concentration. Using the physical data and absorption rate, the rate constants for carbon dioxide absorption by MCHA and DMPD were evaluated. Based on the pseudo-first-order reaction, the rate constants were determined to be k2,MCHA = 2.698 × 107 exp(− 2458/T) and k2,DMPD = 1.002 × 106 exp(− 1511/T). Notably, the activation energies for carbon dioxide absorption by the emulsion absorbents containing MCHA or DMPD were lower than those of alkanolamine solutions.

An 11-month-old boy with unilateral Wilms tumor had an unusual presentation, with dilated hypertensive cardiomyopathy, acute myocarditis, pulmonary edema, and congestive heart failure secondary to the Wilms tumor and requiring intensive care. After surgery, all of the findings were normalized. According to the literature review there were reported previously in only seven cases with dilated cardiomyopathy. Wilms tumor should be included in the differential diagnosis of any child with dilated cardiomyopathy and an abdominal mass, regardless of the presence of hypertension, especially less than one year old. Also, vasoactive mediators including renin should be evaluated in the case of hypertension.

This study examined whether somatic symptoms and sleep quality can be indicators of depression and suicide risk in Korean military conscripts. In October and November of 2016, a total of 1,937 conscripts completed a survey that included the patient health questionnaire (PHQ) 9, PHQ15, the Mini International Neuropsychiatric Interview Plus suicidality module, and the Pittsburgh sleep quality index. Four groups were formed by depression and suicide risk status. Results from analyses of covariance indicated that overall, the severity of somatic symptoms and aspects of sleep quality were higher in conscripts with both depression and suicide risk, and greater associations of depression with somatic symptoms and sleep quality. The results of logistic regression analyses indicated that moderate to high levels of somatic symptoms and poorly perceived health were associated with the risk of depression and suicide, respectively. Poor sleep quality was associated with a higher risk of depression, but it was not significantly related to suicide risk after accounting for depression, which showed a greater association with suicide risk. Monitoring somatic and sleep complaints along with perceived health are needed as potential markers of depression and suicide risk among military conscripts.

Kinetic and enzymatic inhibition experiments were performed to investigate the effects of methanethiol (MT) and hydrogen sulfide (H2S) on methane oxidation by a methane-oxidizing consortium. In the coexistence of MT and H2S, the oxidation of methane was delayed until MT and H2S were completely degraded. MT and H2S could be degraded, both with and without methane. The kinetic analysis revealed that the methane-oxidizing consortium showed a maximum methane oxidation rate (Vmax) of 3.7 mmol g-dry cell weight (DCW)(-1) h(-1) and a saturation constant (Km) of 184.1 μM. MT and H2S show competitive inhibition on methane oxidation, with inhibition values (Ki) of 1504.8 and 359.8 μM, respectively. MT was primary removed by particulate methane monooxygenases (pMMO) of the consortium, while H2S was degraded by the other microorganisms or enzymes in the consortium. DNA and mRNA transcript levels of the pmoA gene expressions were decreased to ∼10(6) and 10(3)pmoA gene copy number g-DCW(-1) after MT and H2S degradation, respectively; however, both the amount of the DNA and mRNA transcript recovered their initial levels of ∼10(7) and 10(5)pmoA gene copy number g-DCW(-1) after methane oxidation, respectively. The gene expression results indicate that the pmoA gene could be rapidly reproducible after methane oxidation. This study provides comprehensive information of kinetic interactions between methane and sulfur compounds.

The movement of non-indigenous aquatic species (up to about 6000 species) along with ballast water into foreign countries during the shipping process poses concerns to human and environmental health as well as aquatic biodiversity. The International Maritime Organization (IMO) is expected to impose tighter regulations on ballast water discharges in the near future, and consequently, the development of more efficient ballast water treatment processes is required. In this study, the hydrodynamic performance of a static mixer in a ballast system for the complete mixing of injected chemicals and ballast water flowing in the main pipe was numerically investigated. Through several steps (design of mixer shape using numerical methods, CFD simulations, and validation tests), the performance of the static mixer was evaluated. The CFD simulation results showed that the target fluid (water + chemical) was completely mixed at a distance equal to 8 times the pipe diameter downstream of the mixer outlet, and the mixing quality was about 95%. Furthermore, the results of the CFD simulations and the validation tests were in agreement. The results of this study suggest that the use of a static mixer in the disinfection and neutralization system stabilizes the system and minimizes the amount of chemicals consumed.

Background Previous reports mostly from Europe suggested an association between an occurrence of narcolepsy and an influenza A(H1N1)pdm09 vaccine adjuvanted with AS03 (Pandemrix ® ). During the 2009 H1N1 pandemic vaccination campaign, the Korean military performed a vaccination campaign with one type of influenza vaccine containing MF59-adjuvants. This study was conducted to investigate the background incidence rate of narcolepsy in South Korean soldiers and the association of the MF59-adjuvanted vaccine with the occurrence of narcolepsy in a young adult group. Methods To assess the incidence of narcolepsy, we retrospectively reviewed medical records of suspicious cases of narcolepsy in 2007–2013 in the whole 20 military hospitals of the Korean military. The screened cases were classified according to the Brighton Collaboration case definition of narcolepsy. After obtaining the number of confirmed cases of narcolepsy per 3 months in 2007–2013, we compared the crude incidence rate of narcolepsy before and after the vaccination campaign. Results We included 218 narcolepsy suspicious cases in the initial review, which were screened by the diagnostic code on the computerized disease registry in 2007–2013. Forty-one cases were finally diagnosed with narcolepsy in 2007–2013 (male sex, 95%; median age, 21 years). The average background incidence rate of narcolepsy in Korean soldiers was 0.91 cases per 100,000 persons per year. During the 9 months before vaccination implementation (April to December 2009), 6 narcolepsy cases occurred, whereas during the next 9 months (January to September 2010) including the 3-month vaccination campaign, 5 cases occurred. Conclusions The incidence of narcolepsy in South Korean soldiers was not increased after the pandemic vaccination campaign using the MF59-adjuvanted vaccine. Our results suggest that the MF59-adjuvanted H1N1 vaccine did not contribute to the occurrence of narcolepsy in this young adult group.

The effect on mechanical properties and magnetic properties of hot-deformed magnets with different rare earth (RE) content has been investigated. The results show that the optimal comprehensive magnetic properties are obtained at 13.09 at% RE. The bending strength parallel to c-axis orientation increases with the increasing of RE content, while that perpendicular to c-axis orientation exhibits decrease. Moreover, the micro magnetic structure was observed and the coercivity mechanism of the hot-deformed magnet sample was discussed.

The microstructure of die-upset nanocomposite magnets with different height reduction was studied to investigate the mechanism of texture development in processes of die upsetting coupled with Nd–Cu grain boundary diffusion. At beginning stage of die upsetting process, inhomogeneous Nd–Cu grain boundary diffusion results in two kinds of different grain boundary microstructures. As for adjacent grains with grain boundary phase, the stress-induced solution-precipitation underlies the formation of the platelet-shaped grains and texture enhancement. Whereas there are two types of texture enhancement for the neighboring grains without grain boundary phase: grain boundary sliding and grain devouring. As die upsetting further proceeds, the stress-induced solution precipitation is the dominant mechanism for texture enhancement due to fuller Nd–Cu grain boundary diffusion.

Liquid phase sintering is used to optimize the magnetic properties and temperature stability of (SmGdDy)(Co, Fe, Cu, Zr) z sintered magnet. DyCo 0.51 and Sm 0.67 Dy 0.11 Gd 0.22 (Co 0.693 Fe 0.201 Cu 0.081 Zr 0.0252 ) 7.94 alloys are chosen as liquid phase and main phase, respectively. (SmGdDy)(Co, Fe, Cu, Zr) z permanent magnets are prepared with different content of liquid phase. XRD analysis shows that all magnets consist of Th 2 Zn 17 -type phase and CaCu 5 -type phase. Cellular structure studies indicate that the H1-5 cell boundary phase shifts gradually from thin and part of discontinuous to thick and continuous. The cell size decreases with the increase of the content of liquid phase. In addition, the Cu content in cell boundary phase is getting lower with the increase of LP adding ratio. The homogeneous and continuous cellular structure is got when the adding ratio of liquid phase is 3 wt% and the highest intrinsic coercivity is achieved at room temperature (23.88 kOe) and 200 °C (12.06 kOe). It’s interesting to find that temperature dependence of remanence ( α ) and the temperature dependence of intrinsic coercivity ( β ) can be optimized with the increase of the content of liquid phase, in which the α (20–100 °C) and β (20–200 °C) are −0.0075%/°C and −0.140%/°C for the magnet with 5 wt% liquid phase, and −0.016%/°C and −0.322%/°C for the magnet with 1 wt% liquid phase.