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Continuous cooling transformation (CCT) diagram is an indispensable tool for new product development in the steel industry and it is traditionally plotted via extensive thermomechanical studies. To reduce the cycle time of product development, a machine-learning model to predict the CCT of a new grade (chemistry and processing parameters) has been developed in this work. The idea is to have a holistic predictive model suitable for integrated steel manufacturing plant, instead of having many models for different class of material compositions. A wide range of data set is prepared to this effect and explored with multiple regression-based machine-learning models. Light Gradient Boosting Machine (LGBM) demonstrates exceptional results amongst the rest, and it is topped off with a metallurgical constraint/correction-factor to obtain the final model. The model is validated against test data as well as against some well-established metallurgical correlations and is found to perform fairly well. [ABSTRACT FROM AUTHOR]

In transabdominal histotripsy, ultrasound pulses are focused into the body to noninvasively destroy soft tissues via cavitation. However, the ability to focus is limited by phase aberration, or decorrelation of the ultrasound pulses due to spatial variation in the speed of sound throughout heterogeneous tissue. Phase aberration shifts, broadens, and weakens the focus, thereby reducing the safety and efficacy of histotripsy therapy. This paper reviews and discusses aberration effects in histotripsy and in related therapeutic ultrasound techniques (e.g., high intensity focused ultrasound), with an emphasis on aberration by soft tissues. Methods for aberration correction are reviewed and can be classified into two groups: model-based methods, which use segmented images of the tissue as input to an acoustic propagation model to predict and compensate phase differences, and signal-based methods, which use a receive-capable therapy array to detect phase differences by sensing acoustic signals backpropagating from the focus. The relative advantages and disadvantages of both groups of methods are discussed. Importantly, model-based methods can correct focal shift, while signal-based methods can restore substantial focal pressure, suggesting that both methods should be combined in a 2-step approach. Aberration correction will be critical to improving histotripsy treatments and expanding the histotripsy treatment envelope to enable non-invasive, non-thermal histotripsy therapy for more patients. [ABSTRACT FROM AUTHOR]

This paper studies torsional wave propagation in a poro-viscoelastic medium of finite thickness. The considered medium is clamped between an inhomogeneous poro-elastic medium of finite thickness and a poro-elastic half-space. Both finite layers are initially stressed and the half-space is self-weighted. Classical dynamical coupled theories have been used to explore the problem. Interior deformations are calculated analytically. A complex frequency equation has been obtained with the aid of suitable boundary conditions. The decomposition of the complex frequency equation into real and imaginary parts provides dispersion and damping equations. These frequency equations exhibited their reliance on the variation of attenuation coefficient, dissipation factor, inhomogeneity, initial stresses, Biot's gravity, porosity and thickness ratio parameters. The impacts of the aforesaid parameters have been extensively studied and demonstrated graphically. [ABSTRACT FROM AUTHOR]

This article reports the microwave integrated detector and its processing circuit. The microwave-integrated detector is fabricated by the GaAs microwave circuit technology. The processing circuit consists of an amplifier, a filter, an analog-to-digital conversion (ADC), a micro control unit (MCU), and a liquid crystal display (LCD). The integrated detector can detect power, frequency, and phase signal of microwave. Besides, the processing circuit can process and display the collected signal. In the experiment, the microwave signal generator send a random signal to the microwave integrated detector. Then, the processing circuit can amplify and filter the signal from the detector. Finally, the LCD can display the random signal. [ABSTRACT FROM AUTHOR]

The present study was conducted to identify the kinematic variables associated with dolphin kick performance during the acceleration and deceleration phases. Nine male competitive swimmers performed 3–5 × 15-m dolphin kick swimming trials with maximum effort. The underwater motion of the dolphin kick was recorded using a digital video camera for a two-dimensional motion analysis. Upper-lower trunk and leg angles in addition to shoulder, hip, and knee joint angles were calculated as kinematic variables. The average horizontal velocity of the greater trochanter during two cycles of the dolphin kick correlated with the angular displacement of the lower trunk in the acceleration (r = −0.715, p < 0.05) and deceleration phases (r = 0.682, p < 0.05). Furthermore, greater angular displacement of the lower trunk was associated with smaller angular displacement of the upper leg and greater angular displacement of the hip, knee, and lower leg in both phases. These results suggest that the movement of the lower trunk is a key kinematic variable for dolphin kick performance, and also that swimming coaches and swimmers need to focus on the movement of the lower trunk as well as upper-lower legs in order to improve dolphin kick motion. [ABSTRACT FROM AUTHOR]

Cryogenic treatment is a thermal treatment process in which the parts are usually cooled to temperatures below −70 C (< 203 K) to induce metallurgical changes in materials. The treatment has shown a significant performance improvement in most of the ferrous materials and it's alloy, by transforming retained austenite to martensite and precipitating secondary carbides. However, the effect of such low-temperature treatment on highly stable super hard material like tungsten carbide (commonly referred to as "cemented carbide") is uncertain. But researchers have reported precipitation of eta-phase carbides, densification of cobalt binder, refinement of tungsten carbide grains, phase transformation of cobalt, and changes in residual stress in cryogenically treated tungsten carbide (WC-Co) material which resulted in increased hardness and wear resistance. Hence, this paper focuses on summarizing the cryogenic treatment parameters used in different studies, the rate of performance improvement in different applications, and reported mechanical and metallurgical changes, which would serve as a pool of knowledge for future researchers. [ABSTRACT FROM AUTHOR]

Introduction: The radiofrequency ablation (RFA) of liver cancer is a desirable treatment option, as it is minimally invasive. An accurate numerical simulation can greatly help physicians better plan their surgical protocols. Previously, the displacement current in the RFA process was considered negligible, and therefore RFA simulation was modeled as a direct current (DC) system instead of an alternating current (AC) system. Our study investigated the hypothesis that the displacement current in the RFA process should not always be considered negligible. Methods: AC measurements of ex vivo bovine liver ablation were performed, and numerical simulations were also conducted to test the hypothesis that the relative permittivity would significantly decrease after the liver tissue reached a high temperature. Results: The displacement current was observed to be a sizable fraction of the conduction current, especially before the onset of the first pause. The simulation results indicated that the relative permittivity is likely to decrease to several hundred or lower at elevated temperatures. Conclusions: Our study results suggest that the DC model may be inadequate, especially before the first roll-off and that additional information could be available during RFA treatment by considering the AC nature of RFA, which could lead to improved numerical simulation. Additional measurements of tissue parameters are needed to reach the full potential of the AC model for further development of ablation control. [ABSTRACT FROM AUTHOR]

Body waves may affect phase velocity obtained from microtremor array surveys in some rare cases. Fitting theoretical phase velocities based on a surface-wave theory to observed phase velocities affected by body waves would therefore result in distorted images of subsurface S-wave velocity structure. In this study, we present a method for the theoretical calculation of phase velocities in which the full-wave field (i.e. a wavefield including not only surface waves but also body waves) is taken into account. In numerical experiments conducted in this study, in which we considered the full-wave field, we generated synthetic microtremors by randomly distributing point vibration sources on the surface of a horizontally stratified velocity model. We then determined the phase velocities by applying the spatial autocorrelation (SPAC) method to the synthetic vertical-component wave data. The phase-velocity dispersion curve thus obtained exhibited a shape with a clear peak, with a peak value (peak phase velocity) exceeding the S-wave velocity of a bedrock in the model, which was not explainable with a surface-wave (Rayleigh-wave) theory. We conducted systematic numerical experiments and clarified the following two features of the peak phase velocity: (1) the peak phase velocity becomes large as the contrast of the S-wave velocities between the surface layer and the bedrock, or the P-to-S-wave velocity ratio (related to the Poisson's ratio) in the surface layer gets large, and (2) the frequency at which peak phase velocity occurs (peak frequency) lies in the vicinity of the S-wave resonance frequency of the ground. Both the peak phase velocity and the peak frequency were theoretically reproduced by the calculation method that we propose in this study, based on a SPAC method modified to consider the full-wave field. These results imply the possible improvement in the accuracy of microtremor array survey analysis for velocity-structure inference, by applying a full-wave theory to the peak phase velocity. [ABSTRACT FROM AUTHOR]

The non-invasive, cost-effective and radiation-free methodology of ultrasound imaging procedures makes it a convenient tool for the detection of tumours. But, usually, the diagnosis efficiency and accuracy of detection is affected by speckle, intensity inhomogeneities and low contrast. For tumour detection, identifying and segmenting the tumour region is vital. In this proposed work, active contours based segmentation is employed with the initial contour achieved using a thresholding method involving a novel concept of phase gradients. Initially, the raw US image is de-speckled and enhanced using the neutrosophic transformation concept. This pre-processed US image is then thresholded using adaptive constraints derived from the mean, texture (using Gabor filters), gradient, phase information and phase gradient of the image. Then the obtained thresholded image is used as the initial mask/contour for segmentation based on active contours using localized image energies. The proposed methodology gave improved tumour boundary delineations even for challenging tumour echogenicities. [ABSTRACT FROM AUTHOR]

X-ray diffraction and calorimetric investigations were performed for 80GeS2-20Ga2S3, 82GeS2-18Ga2S3 and 84GeS2-16Ga2S3 chalcogenide glasses. It is shown that structure of these glasses is characterized by short range ordering. It is established that Ga2S3 and GeS2 phases can be crystallized in Ge-Ga-S system. Transformation of voids in crystallized (80GeS2-20Ga2S3)100-х(СsCl)x, x = 0; 5; 10; 15 chalcogenide glasses was studied by positron annihilation lifetime spectroscopy. The CsCl content in GeS2-Ga2S3 glassy matrix changed the defect-related component in positron lifetime spectra and confirmed the structural void agglomeration in comparison with the base glass. A larger amount of CsCl in (80GeS2-20Ga2S3)85(СsCl)15 glass resulted in void fragmentation due to loosening of the structure. [ABSTRACT FROM AUTHOR]

Sheet blanks from copper (M1) and aluminium alloys (AD1, AD32) with a thickness of 3 mm are joined in butt joints and overlap, butt joints - overlap joints by friction stir welding (FSW). The microstructure, mechanical properties and phase components of the welded joints obtained by the FSW are studied by using various methods of metal physics analysis, including X-ray diffraction, mechanical tensile and bending tests, etc. The test results showed that high quality of the welded joint can be achieved when tool rotation is 900 min-1 and the welding speed is 25 mm/min when the angle of tool inclination angle is 3°. The maximum value of the tensile strength is about 66 MPa. Copper and aluminium alloys are formed due to solid-phase mixing in the superplastic state (SPS), forming a characteristic shear-strip-layered structure with alternating layers in zone of weld seam cores (WSC). A mixed structure with characteristic fragments of Cu and Al is formed on the aluminium side on the side of the WSC. New intermetallic phases were not detected in the WSC centre. [ABSTRACT FROM AUTHOR]

To investigate the relationship between light sensing systems in the eye and circadian oscillators in the hypothalamus of subterranean rodents, we studied subterranean Mandarin voles (Lasiopodomys mandarinus) that spend their entire lives under dark conditions with degenerated eyes, and compared oscillatory expression patterns of clock genes in the hypothalamus and eye between Mandarin voles and their aboveground relatives, Brandt's voles (L. brandtii). Individuals of both vole species were kept under a 12-h light/12-h dark condition or continuous dark condition for 4 weeks. In both species, the expressions of most genes showed significant cosine rhythmicity in the hypothalamus but relatively weak rhythmicity in the eye. The number of rhythmic genes in the eye of Mandarin voles increased under the dark condition, but the opposite trend was observed in the eye of Brandt's voles. The expression levels of most clock genes in the hypothalamus of both vole species did not significantly differ between the two conditions, but unlike in Mandarin voles, these expression levels significantly decreased in the eye of Brandt's voles kept under the dark condition. In both vole species, the peak phase of most clock genes exhibited advanced or invariant change in the hypothalamus under the dark condition, and the peak phase of most clock genes showed consistent changes between the eye and hypothalamus of Mandarin voles. However, most clock genes in the eye showed a delayed phase in Brandt's voles kept under the dark condition. In conclusion, the hypothalamus plays an important role in both vole species irrespective of the light condition. However, the expression patterns of clock genes in the eye differed between the vole species, indicating that each species adapted differently to their environments. [ABSTRACT FROM AUTHOR]

In this paper, a method for characterizing solution concentration variation based on quantitative phase imaging (QPI) is proposed with advantages of visualization, non-invasiveness and high speed. Through the phase imaging system, the full-field phase shift of the solution to the reference sample is obtained, and the sampling points are determined by taking the modulus squared of the phase gradient. Phase imaging experiments based on CaCl2 solutions are implemented to verify the feasibility of this method. The experimental results demonstrate that the optical phase distribution can be used to characterize the region of concentration change conveniently. The concentration-phase function is substituted into the simulated neuronal dynamics model Chay, then the optical phase information is successfully applied to describe the bursting pattern of a neuron in simulation, which indicates a good application prospect in the fields of industry and biology. [ABSTRACT FROM AUTHOR]

Cost-effectiveness, simple processing, and high performance are crucial factors for Ti and its alloys development. The high cost of Ti and its alloys comes from both starting materials and complex fabrication and/or machining processes which could be controlled using low-cost starting materials and appropriate near-net-shape fabrication techniques. In this study, the low-cost Ti is prepared, from a mixture of pure-Ti and TiH2 powders, via a powder metallurgy route consisting mechanical milling (MM) followed by dehydrogenation, and subsequent compaction through Spark Plasma Sintering (SPS). The MM mixture of Ti and TiH2 was dehydrogenated at 1073 K, prior to sintering, for various time periods up to 10.8 ks. The microstructural evolution caused by different dehydrogenation time and its effect on the mechanical properties has been investigated. The microstructure of sintered Ti consists of controlled bimodal type acicular α and δ-hydride phases. Consequently, the bimodal-type Ti prepared from a blend of pure-Ti and TiH2 powders exhibited a superior strength of up to 675 MPa, which is higher than that of the Ti prepared by solely pure-Ti powder. [ABSTRACT FROM AUTHOR]

Studies on circadian timing in depression have produced variable results, with some investigations suggesting phase advances and others phase delays. This variability may be attributable to differences in participant diagnosis, medication use, and methodology between studies. This study examined circadian timing in a sample of unmedicated women with and without unipolar major depressive disorder. Participants were aged 18–28 years, had no comorbid medical conditions, and were not taking medications. Eight women were experiencing a major depressive episode, nine had previously experienced an episode, and 31 were control participants with no history of mental illness. Following at least one week of actigraphic sleep monitoring, timing of salivary dim light melatonin onset (DLMO) was assessed in light of <1 lux. In currently depressed participants, melatonin onset occurred significantly earlier relative to sleep than in controls, with a large effect size. Earlier melatonin onset relative to sleep was also correlated with poorer mood for all participants. Our results indicate that during a unipolar major depressive episode, endogenous circadian phase is advanced relative to sleep time. This is consistent with the early-morning awakenings often seen in depression. Circadian misalignment may represent a precipitating or perpetuating factor that could be targeted for personalized treatment of major depression. [ABSTRACT FROM AUTHOR]

The Hierarchical Factor Segmentation (HFS) method is a non-parametric statistical method for detection of the phase of a biological rhythm shown in an actogram. The detection accuracy of this method was measured on actograms showing only circadian rhythms with a constant ratio of signal to noise (S/N). In the present study, we generated 84 types of artificial actograms including circadian or circatidal rhythms by using three parameters: α/ρ, S/N and period length τ, and evaluated the effectiveness of our devised adaptation of the HFS method, the cycle-by-cycle adaptation. The results showed the effectiveness of the cycle-by-cycle adaptation was high even though S/N or τ was fluctuating through a whole actogram. These suggested that the cycle-by-cycle adaptation could be effectively applied to various kinds of rhythmic activity data. The C++ source code of the cycle-by-cycle adaptation is available on the website at . [ABSTRACT FROM AUTHOR]

Seismic wavelet estimation is the bedrock of seismic-well tying and seismic inversion but remains a challenge. Huge amounts of effort have been expended on seismic wavelet estimation and determining the amplitude and phase spectrum is a time-consuming task. In this article, we develop a workflow to determine automatically the constant phase of an estimated wavelet. This workflow begins with statistical wavelet estimation and seismic-well tying. We then extract a new seismic wavelet with a constant phase by using the well and seismic data together. To obtain the best phase for the extracted wavelet using well and seismic data, we rotate the phase of the wavelet by a user-defined increment and perform automatic seismic-well tying for each phase-rotated wavelet. The phase that reaches the maximum correlation coefficient between the synthetic and seismic data is regarded as the best phase for wavelets in each iteration. We next update the time–depth relation using the best seismic-well tie (the maximum correlation coefficient). We repeat the wavelet estimation using well and seismic data, phase rotation, automatic seismic-well tying and time–depth updating until the difference between wavelets, and time–depth relationships, in the current and previous iterations is below a user-defined threshold. [ABSTRACT FROM AUTHOR]

In this paper, a 2D orthogonal cutting of hardened AISI52100 steel is developed to investigate the influence of cutting process parameters (CPP) on white layer (WL) thickness. A finite element model (FEM) based on the phase transformation mechanism and takes into account the mechanical effects is adopted to predict the WL depth. Several numerical simulations are performed in various conditions of tool geometry, tool flank wear, material properties, and cutting conditions. The predicted results of cutting forces, chip morphologies, and WL depth are physically consistent with the previous experimental investigations. The numerical results prove that formation of thick WLs is unavoidable in all cases, except for low workpiece hardness, very thin WLs are noticed. The results also confirm that the WL thickness depends on all used CPP. In particular, the cutting speed, feed, tool flank wear, and workpiece hardness are the most influencing parameters. [ABSTRACT FROM PUBLISHER]

The chiral smectic subphase with three-layer structure, SmCγ*, is now of great interest from the point of view of device technologies such as multistate or symmetric switching. We report that the unique nonlinear electrooptic response can serve as precise mark of the phase transition into three-layer structure. The problem is illustrated with the first and third harmonic electro-optic spectra. Furthermore, the characteristic response of the helical liquid crystal phases correlated with particular collective modes using the Debye-type relaxation method for the well-known prototype liquid crystal material (MHPOBC) are presented. [ABSTRACT FROM AUTHOR]

This paper studied the structural design of a ceramic core and a blade, ceramic core localization, shell preparation, casting process, core leaching technology, and the heat treatment process of a single-crystal hollow turbine blade. The results show that the single-crystal structure solidification sequence of the blade platform is consistent with the cooling sequence and the pulling-out direction of the blade. The primary dendrites were obviously enlarged with the increase of the blade thickness owing to the change in the local cooling rate. Besides, the γ′ phase had a high uniform size distribution ranging from 0.40 to 0.60 µm after heat treatment, and the cubic degree was more homogeneous in comparison with the as-cast microstructure, which are favorable for the superalloy structure. Moreover, γ′ phase size gradually increased and its quantity gradually reduced owing to the increase of the wall thickness in the growth direction. [ABSTRACT FROM AUTHOR]

Previously examined lyotropic mixtures sodium dodecyl sulphate (SDS) - 1-decanol (DeOH) - D2O were prepared in four different molar ratios,M= [D2O]/[SDS], whereM= 30, 31, 32 and 33, to study the coexistence of uniaxial discotic (ND) and calamitic (NC) nematic phases as was claimed in recent articles. Those mixtures were investigated in a specific temperature range by laser conoscopy, polarized optical microscopy (POM) and small-angle X-ray scattering (SAXS) to construct partial phase diagram. By combining the results obtained from all these techniques, we could not observe theND−NCphase coexistence in the phase diagram of SDS/DeOH/D2O after the detailed investigation, as it was formerly reported. The results obtained in this study are in a good agreement with symmetry arguments and theoretical predictions but not with literature claims. The present results are also consistent with experimental investigations of other lyotropic mixtures whose phase diagrams were previously identified. [ABSTRACT FROM PUBLISHER]

This paper compares data from various sources concerning the impact of high magnetic field (HMF) on changes that occur in pearlite with respect to microstructure, phase transition, and mechanical properties. HMF raises the transformation temperatures of both ferrite and pearlite. This effect can be enhanced by increasing the carbon content. Other alloying elements may influence austenite decomposition temperature, Curie temperature, and magnetic moment, thus either increasing or decreasing the effect of HMF on phase transformation temperature. By altering the transformation thermodynamics, HMF increases the volume fraction of proeutectoid ferrite, decreases that of cementite, and decreases the lamellar spacing. HMF introduces the microstructure anisotropy and aligns proeutectoid ferrite grains parallel to the direction of the HMF. This effect becomes smaller when the cooling rate is higher. By affecting both phase transformation and the alignment of grains, HMF affects the morphology and microstructure of proeutectic ferrite and pearlite, and, consequently, their mechanical properties and corrosion resistance. [ABSTRACT FROM AUTHOR]

Material models for steels, used widely in numerical simulations of manufacturing chains, require identification of their coefficients on the basis of measurements obtained from laboratory test. Precision of the identification highly influences modelling reliability. This is visible especially in the case of phase transformation models, which are crucial in predicting of the modern Advanced High Strength Steels (AHSS) properties after applied heat treatment. However, identification of phase transformation models for steels based on dilatometric tests presents serious difficulties. Two problems are investigated in the paper i.e. (i) efficiency of the inverse algorithms used for identification of phase transformation models, (ii) final reliability of the identified models in numerical simulations of manufacturing processes. In the work two phase transformation models were selected as an example. The first was a modified JMAK (Johnson-Mehl-Avrami-Kolmogorov) equation. The second was an upgrade of the Leblond equation, in which second order derivative with respect to time was introduced. The identification was performed by coupling the selected model with nature inspired optimization techniques and performing inverse analysis for the experimental data. Dilatometric tests performed for various cooling rates were used as an experiment, which supplies data for the inverse analysis. Finally, validation of identified models is presented by using industrial data. [ABSTRACT FROM PUBLISHER]

Pre-stimulus phase has been shown to influence temporal judgments concerning order, causality and simultaneity. One hypothesis is that phase cycles frame discrete perceptual snapshots over time. Yet, existing studies have explored the effect of pre-stimulus phase on fine-grained temporal judgments whereas no study has shown whether pre-stimulus phase influences sub-second temporal judgments lasting several phase cycles. If effects of phase on fine-grained temporal judgments reflect perceptual framing, then the perception of longer intervals might show some dependency on the frequency of phase cycles. Higher frequencies should promote increased temporal resolution and discrimination. We tested the relationship between the phase and frequency of oscillations and temporal judgments for longer durations. Participants judged the relative duration of two successive intervals lasting several phase cycles each. Pre-stimulus alpha-band and beta-band phase was associated with subsequent temporal judgments, although not sensitivity, therein providing evidence that pre-stimulus phase is related to temporal judgments that span a longer time-scale than has been previously demonstrated. Although we report evidence that peak-frequency of the alpha-band is related to one measure of task performance, this study does not provide evidence that higher peak frequencies of alpha- or beta-band activity are related to improved duration discrimination of longer intervals. [ABSTRACT FROM AUTHOR]

Undulatory underwater swimming (UUS) is one of the major skills contributing to performance in competitive swimming. UUS has two phases- the upbeat is performed by hip extension and knee flexion, and the downbeat is the converse action. The purpose of this study was to determine which kinematic variables of the upbeat and downbeat are associated with prone UUS performance in an elite sample. Ten elite participants were filmed performing three prone 20 m UUS trials. Seven landmarks were manually digitised to calculate eighteen kinematic variables, plus the performance variable- horizontal centre of mass velocity (VCOM). Mean VCOM was significantly correlated with body wave velocity (upbeat r = 0.81, downbeat r = 0.72), vertical toe velocity (upbeat r = 0.71, downbeat r = 0.86), phase duration (upbeat r = -0.79), peak hip angular velocity (upbeat r = 0.73) and mean knee angular velocity (upbeat r = -0.63), all significant at P < 0.05. A multiple stepwise regression model explained 78% of variance in mean VCOM. Peak toe velocity explained 72% of the variance, and mean body wave velocity explained an additional 6%. Elite swimmers should strive for a high peak toe velocity and a fast caudal transfer of momentum to optimise underwater undulatory swimming performance. [ABSTRACT FROM AUTHOR]

Metastable Bi2SiO5phase powders were synthesized successfully by Pechini sol-gel method using a simple starting hydro-alcoholic solution consisting of Bi(NO3)3 · 5H2O, TEOS, citric acid, and PEG-6000. The effects of Bi/Si molar ratio, citric acid, and PEG-6000 on the properties of pure Bi2SiO5powders were investigated. The crystalline phase and fluorescence properties were characterized. The process of Pechini sol-gel method and the effect of purity on fluorescence properties were studied in this paper. X-ray diffraction results illustrate that single phase of Bi2SiO5can be obtained at 650°C for 1 h. Furthermore, the maximum fluorescence emission wavelength of the powders is located at 355 nm, which represents the band gap of Bi2SiO5powders is 3.49 eV. [ABSTRACT FROM PUBLISHER]

The solid solution of (1-x)Bi0.4871Na0.4871La0.0172TiO3-x(Bi0.95Ho0.05)FeO3((1-x)BNLT-xBHF) withx= 0.03–0.09 lead-free ceramics was prepared by the conventional solid-state reaction route. Mixed powders were calcined at 900°C for 4 h. The ceramics were sintered at 1150°C which was the optimum sintering temperature. Densification, phase and microstructure were characterized via Archimedes' method, X-ray diffraction technique and scanning electron microscopy, respectively. The bulk density data of the studied ceramics showed that the concentration of BHF in (1-x)BNLT-xBHF solid solution improved densification of this ceramic system. Only single perovskite phase was observed in XRD patterns of the sintered samples for all conditions. The SEM micrographs for samples with low concentrations of BHF were homologous and smaller grain size than when increasing the concentration of the BHF. The correlation of the properties and the concentration of BHF of these studied ceramics are discussed and compared with other ferroelectric ceramics. [ABSTRACT FROM PUBLISHER]

Microstructural modifications and mechanical properties of samples manufactured from conventional and nanocomposite WC/Co12 powders by means of Selective laser melting (SLM) are compared after processing with the same parameter set. Studying their homogeneity reveals that in both samples coarse and fine carbides segregate in the molten pool. X-ray diffraction (XRD) analysis shows significant changes in the microstructure and crystalline phases present in the WC/Co mixture and after SLM. Thermal decomposition of WC leads to the formation of W2C dicarbides and the appearance of the complex Co-W-C ternary phase. No residual pure cobalt after SLM was detected in the samples. The Williamson–Hall method allows determining coherent WC domain sizes of conventional and nanostructured powders (56 ± 6 nm and 10 ± 3 nm, respectively) and microstrains (∼0 for both) as well as their modifications after SLM processing (180 ± 50 nm and 2 ⋅ 10−3 ± 4 ⋅ 10−4for the nanophased sample, and 330 ± 100 nm and 2 ⋅ 10−3 ± 4 ⋅ 10−4for the conventional one, respectively). The microhardness of the part produced from the nanophased powder is slightly increased in both the coarse (∼1496 HV0.3) and fine (∼1542 HV0.3) carbide segregation regions compared to the sample obtained from the conventional powder (1384 HV0.3and 1515 HV0.3for coarse and fine regions, respectively). [ABSTRACT FROM AUTHOR]

The effect of Ti in Fe substrate on the morphology and growth of Zn–Fe alloy phases in (Zn–0.2 wt.%Al)/Fe diffusion couples was investigated using optical and scanning electron microscopy. It is shown that ζ phase layer does not exist in (Zn–0.2 wt.%Al)/Fe couple, but it can be clearly observed in (Zn–0.2 wt.%Al)/(Fe–Ti) diffusion couples. Increasing of dissolved Ti in Fe substrate delays the disappearance of the ζ phase and promotes the formation of δk phase. The δp phase grows toward the ζ phase layer in the form of arborescence. The growth of total intermetallic phase layers in all diffusion couples is controlled by diffusion of Zn and Fe atoms within the layers at 380 °C. The thickness of total intermetallic layer increases with increasing of dissolved Ti in Fe substrate and reaches the maximum when Ti content is 0.4 wt.%. [ABSTRACT FROM AUTHOR]

This paper will review several phenomena and applications of pneumatic conveying which are unusual in nature and not found in the standard applications of pneumatic conveying in solid processing. The effect of reduced gravity of pneumatic conveying in the space shuttle will be cited along with other earth-based reduced-gravity experiments. In our laboratory, we studied the relationship between dilute and dense-phase conveying proposing a thermodynamic analogy in interpreting pneumatic conveying operations. We also explored the potential to relate the different parameters in pneumatic conveying to a generalized phase diagram. Our laboratory also studied many facets of electrostatics and their effect from elimination of the effect to utilization in the development of flowmeters. It was found that the use of a Roots blower in conveying dilute-phase cement yields some fascinating results that show drag reduction. Also showing unexpected results were the conveyance of particles that undergo a physical transformation when being conveyed at high temperatures. Besides these phenomena, considered another paper considered the effects of soft particles and fibrous material (Klinzing 2015). [ABSTRACT FROM AUTHOR]

The interpenetrating double metal phase composite is anisotropic. According to the structural and mechanical properties, the cutting process becomes more complicated. In this work, experimental investigation was systematically studied by means of turning experiments, and focused on cutting force and surface roughness; extra attention has been paid to the cutting phenomena in the zone of reinforcing phase and bimetal interface. Cutting force performance is similar to the ordinary materials, but there are several impact forces in cutting process. In addition, it is easy to produce cracks and exfoliations at metal/metal interface. These phenomena will lead to the decline of the machined surface quality. [ABSTRACT FROM PUBLISHER]

CulnSe2 as one l-lll-VI ternary compound with direct band gap, has become one of the most promising photovoltaic materials due to high optical absorption coefficient and conversion efficiency. CulnSe2 films were prepared by electrodeposition with CuCl2·2H2O, lnCl3, SeO2 as raw materials. The phases of product films were analyzed by X-ray diffraction (XRD) and the morphology was characterized by scanning electron microscope (SEM). Experimental results show that dense and continuous CulnSe2 films can be obtained under conditions of deposition potential - 0.5 V, pH 2.5 and raw materials ratio 6:8:12:50, and the XRD diffraction peaks of CulnSe2 film are corresponding to (111), (220) and (311) crystal planes respectively, it consists of many rods with about 1 μm length; While the CulnSe2 film obtained under conditions of deposition potential -0.5 V, pH 2.0, and CuCl2·2H2O, lnCl3, SeO2 and C6H5Na3O7&#1832H2O with concentrations of 6 mmol/L, 8 mmol/L, 6 mmol/L, 5 mmol/L respectively, shows different XRD diffraction peaks corresponding to (112), (220) and (312) crystal planes respectively, it consists of many non-uniform particles with diameters about 0.5-1.5 μm distribute on the film surface with dense, continuous and unsmooth morphology. [ABSTRACT FROM AUTHOR]

A general classification of separation methods is attempted. The two criteria were phase transformations and interfacial transfers. All separation methods of homogenous mixtures were divided into five groups: (i) methods that are based on the formation of new phases by substances to be separated; (ii) methods that are based on differences in the interphase distribution processes, chromatographic methods being singled out as a separate group; (iii) membrane methods that are based on induced transfers of substances from one phase into another one across a third phase, which separates the two; (iv) separation methods within a single phase that are based on velocity and direction differences in spatial displacement of particles of substances to be separated within one fluid phase under the action of various fields; and (v) combined methods working combining previously listed methods. Descriptions of each group of separation methods include their intragroup classification and information on the most important techniques as well as the least known of them. These descriptions are in the form of reviews of fundamental and most important publications, regardless of the time they appeared. For the well-known classical methods of the first group all necessary information can be found in university textbooks. [ABSTRACT FROM PUBLISHER]

In this study, Ti and Al elemental powders were used to prepare mixed powder by mechanical alloying. The morphology and phase compositions of mixed powders with different milling durations were investigated by scanning electron microscope, transmission electron microscope and X-ray diffraction. Experimental results show that powders are rapidly refined in the early stage of ball milling. However, during the process of milling, powder particle size reaches to a certain extent and change of particles size is minimal. Analyses show that intermetallic compounds, e.g. Ti3Al, TiAl and TiAl2, are synthesised in the composite powder during such high-energy milling process. A small amount of amorphous products are found in the 40 hours-milled powder. By high-energy ball milling, powder of Ti-45Al can be refined to nanoscale and synthesised intermetallic compounds. It is beneficial for the formation of sintered microstructure of fine and density. In this study, 40 hours-milled powder is found more suitable for following sintering. [ABSTRACT FROM AUTHOR]

The transformation characteristics of low-carbon high strength low alloy steel for various cooling rates were systematically investigated by means of dilatometric measurements and microstructure observations. According to the results, it is recognised that the increase of the cooling rate could lead to microstructure evolution from a mixture of polygonal ferrite, acicular ferrite and bainite ferrite to the dual phase of acicular ferrite and bainite ferrite. The kinetics mechanism of the phase transformation was further studied by a modified analytical phase transformation model, which involves site saturation, diffusion/interface-controlled growth, impingement correction for randomly distributed growing particles. It is demonstrated that diffusion-controlled polygonal ferrite and acicular ferrite phase transformation precedes the interface-controlled bainite ferrite phase transformation. For the diffusion-controlled growth, the transformation is slowed down with the increase of the cooling rate, which prevents the diffusion process to some degree and increases the diffusion activation energy QD. For the interface-controlled growth, the interface migration activation energy shows a declining trend with the increase of cooling rate, thus promoting the transformation. [ABSTRACT FROM AUTHOR]

Selective laser melting (SLM) offers great possibilities to fabricate metal tools with a complex geometry, but there are limitations regarding some materials. This work focuses on the fabrication of AISI 420 stainless steel using SLM for the application of plastic injection mold. The melt characteristic of the powders was firstly concluded, and then the microstructure, phase composition, and hardness were characterized using scanning electron microscopy, X-ray diffraction, and Rockwell hardness test, respectively. The results showed that cellular microstructure was observed along the direction of the maximum heat flow. The proportion of the phases varies with the change of SLM processing parameters, which directly affects on the hardness of the parts. The relative density over 99% was obtained and the highest hardness presents 50.7 HRC, which meets the requirement of plastic injection molding application. [ABSTRACT FROM PUBLISHER]

Purpose: To analyze the extent and prevalence of the placebo effect in prior early-phase glaucoma clinical studies. Methods: Articles were evaluated on phase I and II trials of glaucoma medicines that became commercially available after 1977 with a placebo arm that involved glaucoma patients. Results: We included 23 studies with 23 treatment arms with a total of 1703 patients in articles evaluating 10 different glaucoma medications. This study showed that at 8 AM ( n = 18), the average decrease in placebo from untreated baseline was 2.3 ± 1.6 mm Hg (9%), while for the diurnal curve ( n = 17), the mean decrease was 1.4 ± 1.1 mm Hg (6%). At 8 AM, 8/18 treatment arms had greater than 2 mm Hg intraocular pressure (IOP) decrease, and all had at least some reduction in IOP. For the diurnal curve, 4 of 17 studies had reduced IOP greater than 2 mm Hg. One treatment arm had no placebo effect. Conclusions: This study suggests that a placebo effect is common in glaucoma clinical trials and potentially could limit the ability to evaluate the efficacy of a new medicine. [ABSTRACT FROM AUTHOR]

As a promising gas-sensing material, tungsten tri-oxide with a wide band gap has attracted much attention. However, the preparation of tungsten tri-oxide nanomaterials in alkaline solution faces difficulties because of the weak solubility of the tungsten source. Here, the influence of pH values on the final products was investigated in detail. The results showed that pH value played no role in the phase for the final product. However, it had an obvious impact on the morphology evolution. Gas-sensing properties showed that the sensitivity increased with the increase of synthesised time because of improved crystallinity. Moreover, the sensitivity of the product synthesised in an alkaline environment was obviously higher than that of the product synthesised in an acid environment . [ABSTRACT FROM AUTHOR]

The effect of rapid solidification of a suction cast specimen on the microstructure, magnetocrystalline anisotropy, and magnetic-field-induced strain of the Co1.36Ni1.21AlFe0.12alloy was investigated. The results show that a dual-phase structure consists of L10-type twin martensite with a small amount of coexisting A1-type divorced eutectic γ phase in the specimen. After rapid solidification, the network divorced eutectic γ phase was smashed to pieces by strong suction force and the grain grew in a preferred orientation. At the same time, the specimen after rapid solidification has high magnetocrystalline anisotropy and excellent shape recovery. The trend of twin martensitic rearrangements was evaluated by the O'Handley model, and a relatively large magnetic-field-induced strain was obtained in the specimen with rapid solidification. [ABSTRACT FROM PUBLISHER]

In this study we have performed pharmacophore modeling and built a 3D QSAR model for pyrido-indole derivatives as Janus Kinase 2 inhibitors. An efficient pharmacophore has been identified from a data set of 51 molecules and the identified pharmacophore hypothesis consisted of one hydrogen bond acceptor, two hydrogen bond donors and three aromatic rings, i.e. ADDRRR. A powerful 3D-QSAR model has also been constructed by employing Partial Least Square regression analysis with a regression coefficient of 0.97 ( R2) and Q2 of 0.95, and Pearson-R of 0.98. [ABSTRACT FROM AUTHOR]

A new method to generate cylindrical vector beam carrying helical phase is proposed based on a multiple elliptical core fiber integrated with gold wire. Both the light field distributions in near- and far-field are considered. The simulation results show that the multiple core fiber filled with gold wire in the center can only support low-loss transmission for the analogous azimuthally polarized (AP) light field with discrete rotational symmetric profile in a broadband range, because the resonant coupling between the surface plasmon modes and the fiber core-guided supermodes. The far-field patterns for different number core are demonstrated to represent an effective AP beam. It also acts as an effective broadband transmission filter for azimuthal modes. [ABSTRACT FROM AUTHOR]

The evolution of the carbides and mechanical properties of 7Cr17MoV stainless steel used as cutlery material during cold rolling was investigated in this study. The results demonstrate that the microstructure of the rolled steel is composed of pearlite and spheroidal carbides. After cold rolling, the aggregation of carbides was no longer evident, and the carbides appeared to be small in size and uniformly distributed, whereas carbides in hot-rolled strips are clearly aggregated. Decreasing the thickness of the cold-rolled strips decreased the size of the carbide particles while increasing their number, which improved the particle distribution. A large number of fine, even nano-scaled carbides were observed in the material. The carbide phase, which primarily consisted of M23C6, did not change during cold rolling and annealing. The tensile strength and yield strength first decreased and then increased, and the elongation increased as the thickness of the cold-rolled strips decreased. Dimples and inclusion particles were readily observed upon tensile fracture. The inclusions are identified to be primarily carbides and oxide inclusions. [ABSTRACT FROM PUBLISHER]

Free feeding (FF) with a high fat diet (HFD) causes excessive body weight gain, whereas restricted feeding (RF) with a HFD attenuates body weight gain. The effects of timing of feeding with a HFD (day vs. night) and feeding duration on energy homeostasis have not yet been investigated. In this study, we fed mice a HFD or a normal diet (ND) twice a day, during their active and inactive periods, on a schedule. The amount of food was regulated by feeding duration (2, 4 or 8 h). First, we investigated the effects of 4-h RF during active-inactive periods (ND-ND, HFD-HFD, ND-HFD or HFD-ND). Among all the 4-h RF groups, mice consumed almost the same amount of calories as those in the FF[ND] group, even those fed a HFD. Body weight and visceral fat in these three groups were lower than that in the FF[HFD] group. Second, we investigated the effects of RF duration. Body weight and visceral fat were higher in the 8-h groups than in the 4-h groups. Body weight and visceral fat were higher in the 2-h groups than in the 4-h groups even though the 2-h groups had less food. Third, we investigated the effects of eating a HFD during the inactive period, when RF duration was extended (2, 6 or 12 h). Mice were fed with a HFD during the inactive period for 2 h and fed with a ND during the active period for 2, 6 or 12 h. Body weight and visceral fat in these mice were comparable to those in the FF[ND] mice. The results of our first set of experiments suggest that 4-h RF was an adequate feeding duration to control the effect of a HFD on obesity. The results of our second set of experiments suggest 2-h RF (such as speed-eating) and 8-h RF, representative of eating disorders, are unhealthy feeding patterns related to obesity. The results of our third set of experiments suggest that eating a HFD for a short period during the night does not affect body weight and visceral fat. Taken together, these results indicate that consideration to feeding with a HFD during the inactive period and restricting eating habits relieve the risks of body weight gain and visceral fat accumulation. [ABSTRACT FROM AUTHOR]

A new type of quenching and partitioning steels using martensitic microstructure prior to the quenching and partitioning process was developed. High tensile strength with large total elongation was obtained, leading to superior mechanical properties. The difference between the new type and conventional quenching and partitioning steels was studied. Excellent mechanical properties were attributed to the high volume fraction of total retained austenite, considerable amount of acicular retained austenite and the plasticization of ferrite laths. [ABSTRACT FROM PUBLISHER]

Lead-free piezoelectric ceramics (1−x)Bi0.5(Na0.8K0.2)0.5TiO3-x(Ba0.98Nd0.02)TiO3or (1−x)BNKT-xBNdT (x = 0.05–0.15 mol fraction) were synthesized by conventional mixed-oxide method. All samples had relative densities more than 98% of theoretical values. All compositions had pure perovskite structure and BNdT effectively diffused into BNKT lattice during sintering to form solid solutions. Grain size and shape were slightly affected by BNdT addition. The addition of BNdT into BNKT was also found to affect dielectric, ferroelectric and piezoelectric performances with the maximum values (Tm= 328°C, ϵr= 1736, tanδ = 0.0714, Pr= 21.91 μC/cm2, d33= 228 pC/N) observed in 0.89BNKT-0.11BNdT composition. [ABSTRACT FROM AUTHOR]

Homogenization treatment of as-cast Zn-16Al alloy was investigated. Effects of various parameters on the microstructure transformation and the mechanical properties were researched with the methods of hardness test, tensile test, scanning electron microscopy analysis, etc. The results indicate that 360°C × 8 h with furnace cooling is the most reasonable homogenization process for Zn-16Al alloy. Additionally, a new kind of needle-shaped or shuttle-shaped η phase is observed during the furnace-cooled homogenization, which exhibits an extremely regular distribution with an included angle of 120° and a location between the lamellar eutectoids (α + η). The formation of the new η phase is mainly attributed to the Al-depleted-zones left behind by the decomposition of supersaturated α phase. The α′ phase precipitating from eutectoid reaction α → α′ + η contains a much higher Al-content than that of original α phase. [ABSTRACT FROM PUBLISHER]

Circadian rhythm disturbances have been associated with bipolar disorder (BD) during both the mood episodes and the periods of remission. Circadian phase preferences for the evening have been reported for remitted patients, whereas the amplitude and stability of their rhythms have never been assessed using questionnaires. The primary aim of our study was the validation of a French version of the Circadian Type Inventory (CTI), whereas its secondary aim was the comparison between remitted patients with BD and healthy controls for rhythm stability and amplitude and for phase preference. For this purpose, we used the CTI and the Composite Scale of Morningness (CSM) that assesses phase preference ('morning' or 'evening' type). First, we report here on the validation of the French version of the 11-item Circadian Type Inventory in a sample of 140 remitted patients with BD and 156 healthy controls. Principal components analysis revealed a two-factor structure (FR: flexibility/rigidity scale corresponding to rhythm stability; LV: languid/vigorous scale corresponding to rhythm amplitude) explaining 52% of the variance in the control group and 47% in the bipolar group. Cronbach's alpha was 0.75 for FR and 0.73 for LV. The test-retest reliability was 0.74 for FR and 0.86 for LV (3 wks) and 0.62 for FR and 0.72 for LV (6 mos). LV and FR scores correlated with the Composite Scale of Morningness score ( p < 0.00001 and p = 0.0002, respectively). Second, as compared with controls, patients with BD were more languid ( p < 0.00001) and showed an evening preference ( p = 0.0003), but they did not differ from the controls with regard to flexibility/rigidity. The French version of the CTI appeared to have satisfactory psychometrics characteristics. Bipolar patients exhibited not only abnormalities in phase preference but also in amplitude as measured by languidity. Since circadian rhythm dysfunction has been shown to predict poor functioning and mood relapses in interepisodic patients with BD, this tool would appear to be a promising, easy-to-use, measure of the amplitude and flexibility of circadian rhythms that could enrich the arsenal of assessments used in clinical settings. [ABSTRACT FROM AUTHOR]