Maximum Te Research Articles

Study on effective elastic thickness of lithosphere and its tectonic significance in surrounding area of Ordos Block

Based on EIGEN6C4 gravity field model data and ETOPO1 topographic data, we adopt the correlation analysis method based on Fan wavelet to calculate and analyze the distribution characteristics of effective elastic thickness (Te) and load ratio (F) of lithosphere in surrounding of Ordos block. On this basis, the relationship between the lithosphere Te and geological structure, seismic distribution, terrestrial heat flow and crustal deformation is analyzed. The results show that the lithosphere Te in the surrounding area of the Ordos block is obviously different among the tectonic blocks. The lithosphere Te value is low in the south of Qinling orogenic belt and the east of Fen-Wei graben basin. The maximum lithosphere Te value is distributed in the northwest and northeast margin of Ordos block. The lithosphere Te value is negatively correlated with the load ratio F. Earthquakes mainly occur in areas with low lithosphere Te value. Small lithosphere Te value indicates low strength of lithosphere. In such areas, the ability to resist crustal deformation is weak, and it is easy to generate stress accumulation and breed earthquakes. The area with high terrestrial heat flow value corresponds to low lithosphere Te value, showing a negative correlation. However, this negative correlation does not exist in the northwest margin of Ordos Block and Alashan border area, and the eastern margin of Ordos Lvliangshan area. Haiyuan-Liupanshan area has strong tectonic activity, frequent earthquakes and low lithosphere Te value. The internal strain accumulation of Ordos block is small, and the lithosphere Te value is high. The strain rate of the northern Shanxi fault depression zone is large, but the lithosphere Te value is also large, it is speculated that the terrestrial heat flow is the main factor affecting the lithosphere Te value.

Thomson scattering measurements of electron temperature and electron density in laser-driven Gd plasmas

In this study, we demonstrate the laser intensity scaling of electron temperature in Gd laser-produced plasmas (LPPs) through experiment and simulation. The spatial and temporal profiles of electron density ne and temperature Te in Gd LPPs were directly measured during a drive laser pulse duration of 7 ns at a laser wavelength of 1064 nm using collective Thomson scattering. We found that the measured maximum Te value in Gd LPPs increases with increasing laser intensity IL , with the dependence , in the IL range of 1010–. Radiation-hydrodynamic simulation code of the STAR-2D was performed under identical conditions to those used in the experiment, and extended further to higher laser intensities of up to ; the simulated Te was found to be in good agreement with the experimental data over the used IL range. The simulation indicates that higher overall maximum Te typically exists 50–70 above the target and modifies the dependence as . Experiments reveal that a laser intensity of is required to achieve the optimum condition ( 100 eV and ion charge states , at –) for efficient beyond extreme ultraviolet (EUV) light source. In addition, two spot sizes (150 and 250 in diameter) were used to study the effect of the spot size on the Te profile. Our experimental findings, supported by the simulations, show that larger spots can create uniform Te profiles, higher maximum Te , and larger high-Te regions in LPPs. The results and scaling laws presented in this study provide important information for developing more powerful and energy-efficient EUV light sources.

Effect of external longitudinal magnetic field on the dynamics of pulsed plasma stream

A spectroscopic study is carried out to investigate pulsed plasma stream produced in a coaxial plasma accelerator under the influence of an external longitudinal magnetic field. The dynamics of Argon plasma stream that includes the excitations and emissions of plasma species and its different parameter variations on the application of an external longitudinal magnetic field are reported in this work. The behavior of the ionized and neutral species of argon plasma is studied from their intensity distribution profiles which indicate the occurrence of faster recombination as compared to the field-free case. The variation of pressure reveals a significant influence on the recombination and diffusion process of the plasma species. Moreover, the variation of cathode voltage leads to variation in input energy to the system which influences the ionization and excitation processes of the plasma species. A plasma density (Ne) jump is achieved from 1021–1022 m−3 at a relatively higher pressure ∼8 bar plenum pressure in presence of the magnetic field. Saturation of the emissions and excitations of plasma species are revealed from the intensity profile and electron excitation temperature (Texc) profile which occur at different pressure and voltage both for field and field-free cases. The electron temperature (Te) is estimated using the FLYCHK code by comparing the simulated charge state distributions with the experimental findings. Using known parameters in the code, the different estimated Te shows a linear and an exponential decrement respectively in the absence and presence of the magnetic field. Maximum Te of 2.2 eV is reported which decreases to 1.51 eV at a significant increase of plasma density of 1022 m−3.

Population pharmacokinetics of tanezumab following intravenous or subcutaneous administration to patients with osteoarthritis or chronic low back pain.

Describe population pharmacokinetics of intravenous (IV) and subcutaneous (SC) tanezumab across Phase 2b/3 studies of osteoarthritis and chronic low back pain. Data from 10 studies of IV or SC tanezumab (2.5-20 mg every 8 wk for up to 56 wk) were included in a multistep analysis. In Step 1, a 2-compartment model with linear and nonlinear elimination (based on prior analysis of pre-2015 IV osteoarthritis studies) was expanded to include other pre-2015 studies. In Step 2, post-2015 SC studies were combined into the model. Steps 3 and 4 evaluated impact of baseline nerve growth factor (NGF) and treatment-emergent anti-drug antibodies (TE ADA). SC bioavailability was estimated at 62-76%. The key disposition parameters CL, Vc , Vp and KM were estimated to be 0.133 L d-1 , 2.6 L, 1.77 L and 31.2 μg L-1 , respectively. Plasma tanezumab concentration was predicted to reach Cmax at 8.9-11.2 days following single and multiple SC administration in typical patients within the dose range of SC Phase 3 studies (2.5-10 mg every 8 wk). Exposure of a typical patient was similar between IV and SC for the second part of the dosing interval (wk 4-8). Covariates selected on the absorption parameters were weight, age, sex and injection site. Baseline NGF had minimal effect on maximum elimination capacity and TE ADA status was associated with slightly higher tanezumab clearance (6-7%). Our model adequately described plasma tanezumab concentration vs. time following IV or SC administration. Weight was the most influential covariate with respect to absorption of tanezumab in comparison to patient population (osteoarthritis and chronic low back pain) or other demographics. There was no clinically relevant effect of baseline NGF or TE ADA on tanezumab PK.

Tracking blood pressure changes by means of non-invasive intermittent blood pressure measurements in clinical application

Abstract Considering accuracy/precision cut-offs of 5 ± 8 mmHg and cut-off values for inter-class correlation coefficients (ICC=0.37...1, from DIN EN ISO 81060-2), absolute and relative errors in time independent measurement of blood pressure changes with non-invasive intermittent devices (NiBP) are derived mathematically for mean arterial blood pressure range of 40-180 mmHg. As a clinically relevant value for change of arterial blood pressure 20% of the baseline blood pressure is considered. The mean ratio between the change of BP measured by the NiBP and measured by the invasive reference device (TE%) were proposed as quality measure for the evaluation of NiBP device tracking capability. The proposed measure TE%is theoretically independent of absolute accuracy but depends on precision and ICC of a device. NiBP devices show considerable maximum TE% of 41% in tracking mean blood pressure changes respectively. In 10% of the measurements in the low blood pressure range TE% exceeding 100%. The mean 50th/90th TE% percentile over the whole blood pressure range were 25/61%, respectively. Furthermore, TE% was relatively insensitive to assumed blood pressure range but sensitive to ICC. NiBP devices have high relative error in tracking blood pressure changes that make those devices not well-suited for tracking blood pressure changes. The proposed tracking error allows the definition of reasonable accuracy/precision requirements of NBP devices.

Optimization of friction stir welding parameters of dissimilar aluminium alloys 6061 and 5083 by using response surface methodology

Aluminium and its alloys are lightweight, corrosion-resistant, affordable and high-strength material and find wide applications in shipbuilding, automotive, constructions, aerospace and other industrial sectors. In applications like aerospace, marine and automotive industries, there is a need to join components made of different aluminium alloys, viz. AA6061 and AA5083. In this study friction stir welding (FSW) is used to join dissimilar plates made of AA6061-T6 and AA5083-O. The effect of varying tool pin profile, tool rotation speed, tool feed rate and tilt angle of the tool has been investigated on the tensile strength and percentage elongation of the welded joints. Box-Behkan design, with four input parameters and three levels of each parameter has been employed to decide the set of experimental runs. The regression models have been developed to investigate the influence of welding variables on the tensile strength and elongation of the welded joint. It is revealed that with the increase in welding parameters like tool rpm, tool feed rate and tilt angle of the tool, both the mechanical properties increase, reach a maximum level, followed by a decrease with further increase in the value of parameters. Amongst different types of tool pin profiles used, the FSW tool having straight cylindrical (SC) pin profile is found to yield the maximum strength and elongation of the welded joint for different combinations of welding parameters. Multiple response optimization indicates that the maximum UTS (135.83 MPa) and TE (4.35%) are obtained for the welded joint fabricated using FSW tool having SC pin profile, tilted at 1.11° and operating at tool speed and feed rate of 1568 rpm and 39.53 mm/min., respectively.

Seasonal metabolic flexibility is correlated with microclimate variation in horned larks and house sparrows.

Maximum and minimum metabolic rates in birds are flexible traits and such flexibility can be advantageous in variable climates. The climatic variability hypothesis (CVH) posits that more variable climates should result in greater metabolic flexibility for geographically distinct populations. Whether the CVH applies to sympatric species occupying microclimates differing in variability is unknown. Microclimates of open habitats are likely more variable than those of sheltered habitats. If the CVH extends to microclimates, we expect birds from open habitats to show greater flexibility than those from sheltered habitats. To test this extension of the CVH, we compared seasonal variation in microclimates and metabolic rates for sympatric horned larks Eremophila alpestris, which occupy open habitats, and house sparrows Passer domesticus, which occupy sheltered habitats. We measured operative temperature (Te, an integrative measure of the thermal environment), summit metabolic rate (Msum, maximal cold-induced metabolic rate), and basal metabolic rate (BMR, minimal maintenance metabolic rate) in summer and winter. For both winter and summer, daily minimum Te was similar between open and sheltered habitats but maximum Te was higher for open habitats. Winter microclimates, however, were colder for open than for sheltered habitats after accounting for convective differences. Both species increased Msum in winter, but seasonal Msum flexibility was greater for larks (43%) than for sparrows (31%). Winter increases in BMR were 92.5% and 11% for larks and sparrows, respectively, with only the former attaining statistical significance. Moreover, species * season interactions in general linear models for whole-organism metabolic rates were significant for BMR and showed a similar, although not significant, pattern for Msum, with greater seasonal metabolic flexibility in horned larks than in house sparrows. These results suggest that extending the CVH to sympatric bird species occupying different microclimates may be valid.

Degenerately Doped Semi‐Crystalline Polymers for High Performance Thermoelectrics

AbstractThermoelectric (TE) energy conversion in conjugated polymers is considered a promising approach for low‐energy harvesting and self‐powered temperature sensing. To enhance the TE performance, it is necessary to understand the relationship between the Seebeck coefficient (α) and electrical conductivity (σ). Typical doped polymers exhibit α–σ relationship that is distinct from that of inorganic materials due to their large structural and energetic disorder, which prevents them from achieving the maximum TE power factor (PF = α2σ). Here, an ideal α–σ relationship in the Kang–Snyder model following a transport parameter s = 1 is demonstrated with two degenerately doped semi‐crystalline polymers, poly[(4,4′‐(bis(hexyldecylsulfanyl)methylene)cyclopenta[2,1‐b:3,4‐b′]dithiophene)‐alt‐(benzo[c][1,2,5]thiadiazole)] (PCPDTSBT) and poly[(2,5‐bis(2‐hexyldecyloxy)phenylene)‐alt‐(5,6‐difluoro‐4,7‐di(thiophen‐2‐yl)benzo[c][1,2,5]thiadiazole)] (PPDT2FBT) using a sequential doping method. The results allow the realization of the PFs reaching theoretic maxima (i.e., 112.01 µW m−1 K−2 for PPDT2FBT and 49.80 µW m−1 K−2 for PCPDTSBT) and close to metallic behavior in heavily doped films. Additionally, it is shown that the PF maxima appear when the doping state switches from non‐degenerate to degenerate. Strategies towards an optimal α–σ relationship enable optimization of the PF and provide an understanding of the charge transport of doped polymers.

Toward a Structural Model for the Aluminum Tellurite Glass System

Neutron diffraction, 27Al MAS NMR, and 27Al Double Quantum MAS NMR results are presented and analyzed to determine the local environments of the cations in a series of aluminum tellurite glasses. Total scattering results show that, within a maximum Te–O distance of 2.36 Å, tellurium exhibits a mix of [TeO3E] and [TeO4E] environments (E = electron lone-pair), with a linear reduction in the average tellurium–oxygen coordination number as Al2O3 is added to the glass. This is accompanied by a linear decrease in the average aluminum–oxygen coordination number as [AlO4] units form at the expense of [AlO6] units, while the fraction of [AlO5] units remains roughly constant. A consideration of the bonding requirements of the five structural units in the glass, [TeO3E], [TeO4E], [AlO4], [AlO5], and [AlO6], has allowed a direct quantitative relationship between tellurium–oxygen and aluminum–oxygen coordination numbers to be derived for the first time, and this has been successfully extended to the boron tellurite system. Double Quantum 27Al MAS NMR indicates that, in contrast to previous reports, the shortest Al...Al separations are significantly smaller (∼3.2 Å) than expected for a uniform distribution and there is a preference for [AlO6]–[AlO6] and [AlO4]–[AlO4] corner sharing polyhedra. These associations support a new structural model which successfully applies the principle of charge balance to describe the interaction of tellurium and aluminum and identifies and explains the clustering of [AlOn] polyhedra in the glass and their preferred associations. [AlO6] and [TeO4E] units dominate the network in TeO2-rich glasses and [AlO4]− units form to stabilize the [TeO3E]+ units as alumina is added to the glass.

Simulations of Ar seeding by SOLPS-ITER for a slot-type divertor concept

In order to fulfill the requirements for future high-power and long-pulse discharges in the Experimental Advanced Superconducting Tokamak, the present lower graphite divertor will be upgraded with tungsten (W) materials. For one of the new divertor options obtained during the physics design phase, simulations of argon (Ar) seeding are performed by using the SOLPS-ITER code suite. Besides the deuterium and Ar species, all the ionization states of W species generated through physical sputtering have been included in the simulations. As the seeding rate increases, the total power dissipation dominated by Ar radiation increases gradually. Obvious Ar radiation loss in the divertor region is observed. Meanwhile, a high pressure area in the scrape-off layer side of the outer strike point is formed near the corner due to the closed structure. As a result, the outer divertor detaches before the inner divertor, and the maximum Te at the outer target reduces to 5 eV at a puffing rate of 4.0 × 1019 atoms/s. The total heat flux onto the inner and outer target plates, dominated by the charged particles, can be reduced simultaneously. The sputtering rate of W atoms along the divertor plates and the distribution of W impurities in the poloidal cross section are given. The W concentration inside the last closed magnetic flux surface can be controlled to the order of 10−5.

Design of a Si-based Lattice-matched GeSn/SiGeSn Multi-quantum-well Laser

By calculating the heterojunction band alignment of GeSn/SiGeSn, a Ge0.9Sn0.1/Si0.14Ge0.71Sn0.15 multi-quantum-well laser was designed, where three Ge0.9Sn0.1 layers act as wells separated by three Si0.14Ge0.71Sn0.15 layers as barriers. The maximum TE gain reaches 7000 cm−1 at 0.5 eV, and the maximum TM gain reaches 5500 cm−1 at 0.52 eV. The modal gain of the Ge0.9Sn0.1/Si0.14Ge0.71Sn0.15 multi-quantum-well laser we proposed and designed can reach 100 cm−1 with a current density of 5 kA/cm2. The result indicates that it is possible to obtain a Si-based laser.

Magnetic resonance fingerprinting with dictionary-based fat and water separation (DBFW MRF): A multi-component approach.

PurposeTo obtain a fast and robust fat‐water separation with simultaneous estimation of water T1, fat T1, and fat fraction maps.MethodsWe modified an MR fingerprinting (MRF) framework to use a single dictionary combination of a water and fat dictionary. A variable TE acquisition pattern with maximum TE = 4.8 ms was used to increase the fat–water separability. Radiofrequency (RF) spoiling was used to reduce the size of the dictionary by reducing T2 sensitivity. The technique was compared both in vitro and in vivo to an MRF method that incorporated 3‐point Dixon (DIXON MRF), as well as Cartesian IDEAL with different acquisition parameters.ResultsThe proposed dictionary‐based fat–water separation technique (DBFW MRF) successfully provided fat fraction, water, and fat T1, B0, and B1+ maps both in vitro and in vivo. The fat fraction and water T1 values obtained with DBFW MRF show excellent agreement with DIXON MRF as well as with the reference values obtained using a Cartesian IDEAL with a long TR (concordance correlation coefficient: 0.97/0.99 for fat fraction–water T1). Whereas fat fraction values with Cartesian IDEAL were degraded in the presence of T1 saturation, MRF methods successfully estimated and accounted for T1 in the fat fraction estimates.ConclusionThe DBFW MRF technique can successfully provide T1 and fat fraction quantification in under 20 s per slice, intrinsically correcting T1 biases typical of fast Dixon techniques. These features could improve the diagnostic quality and use of images in presence of fat.

Feasible portfolios under tracking error, β, α and utility constraints

The investment nous of active managers is judged on their ability to outperform specified benchmarks while complying with strict constraints on, for example, tracking errors, β and Value at Risk. Tracking error constraints give rise to a tracking error frontier – an ellipse in risk/return space which encloses theoretically possible (but not necessarily efficient) portfolios. The β frontier is a parabola in risk/return space and defines the threshold of portfolios subject to a specified β requirement. An α - TE frontier is similarly shaped: portfolios on this frontier have a specified TE for a maximum TE. Utility and associated risk aversion have also been explored for constrained portfolios. This paper contributes by establishing the impossibility of satisfying more than two constraints simultaneously and explores the behavior of these constraints on the maximum risk-adjusted return portfolio (defined arbitrarily here as the optimal portfolio).

Interchangeability of Procalcitonin Measurements Using the Point of Care Testing i-CHROMATM Reader and the Automated Liaison XL.

Our aim was to verify if procalcitonin (PCT) measurements using the new point-of-care testing i-CHROMATM are interchangeable with those of Liaison XL. One hundred seventeen serum samples were processed sequentially on a Liaison XL and i-CHROMATM. Statistical analysis was done using the Passing-Bablok regression, Bland-Altman test, and Cohen's Kappa statistic. Proportional and constant differences were observed between i-CHROMATM and Liaison XL. The 95% CI of the mean bias% was very large, exceeding the maximum allowable TE% and the clinical reference change value. However, the concordance between methods at the clinical relevant cutoffs was strong, with the exception of the 0.25 ng/mL cutoff which was moderate. Our data suggest that i-CHROMATM is not interchangeable with Liaison XL. However, while the strong concordance at the clinical relevant cutoffs allows us to consider i-CHROMATM a suitable option to Liaison XL to support clinicians' decision-making; nevertheless, the moderate agreement at the 0.25 ng/mL cutoff recommends caution in interpreting the data around this cutoff.

Enhanced thermoelectric performance of CNT/P3HT composites with low CNT content.

Carbon nanotubes (CNTs) have emerged as one of the leading additives for improving the thermoelectric properties of organic materials due to their unique structure and excellent electronic transport properties. However, since as-grown CNTs generally possess different diameters, it is of high interest to determine the influence of the diameter of carbon nanotubes on the thermoelectric properties of CNT/poly(3-hexylthiophene) (P3HT) composite films. Herein, we prepared CNT/P3HT composite films with diameters of <8 nm, 8–15 nm, 20–30 nm, 30–50 nm and >50 nm and studied their thermoelectric properties. It was found that the diameter of CNTs had an important influence on the TE performance of the composite films. The P3HT-dCNT (<8 nm) and P3HT-dCNT (8–15 nm) composite films exhibited almost the same thermoelectric performance and almost more than double that of the other three composite films with increased CNT diameter. The different mass fractions of CNT/P3HT composite films have also been investigated. The maximum TE power factor of CNT (d < 8 nm)/P3HT composite films reached 49.0 μW mK−2 at the mass fraction of 95 wt% P3HT, that is, 5 wt% CNTs. This superior TE power factor of CNT (d < 8 nm)/P3HT composite films can be ascribed to the fully connected interlayer of the P3HT polymer and also the heterogeneous dispersion of short-length CNTs.

Origin of the Dongsha Event in the South China Sea

Post-rift tectonic activities have been widely observed in the northern continental margin of the South China Sea, especially during the late Miocene. Large numbers of faults became active. Unconformities, uplift of faulted blocks, sequence tilting, erosion along the Dongsha massif and canyon incision were also discriminated at this stage in the Pearl River Mouth basin (PRMB) and the area to the east. This tectonism has been named Dongsha Event. A number of hypotheses have been put forward to explain the mechanism of the Dongsha Event, such as high-velocity lower crustal flow, magmatic underplating, and arc–continent collision. To investigate the tectonic dynamics, sequence contact relationships, fault activities, and magmatism were analyzed along large numbers of seismic profiles that cover the eastern PRMB and Southwest Taiwan Basin. The timing, affected regions, and differences in the intensity of tectonic deformation were assessed, upon which the plate bending model was favored. In order to check the reasonableness of plate bending model, effective elastic thickness and other geodynamic parameters were calculated constrained by uplift area width and regarding the trench as sediment filling. A maximum Te value of ~27 km and a minimum value of ~4 km were obtained. Integrating with the former stress field calculation, we conclude that the Dongsha Event was mainly affected by subduction and collision of the South China Sea toward the Philippine Sea plate. This event commenced at about 10 Ma and peaked at around 3.6 Ma. Although the high effective elastic thickness required is a problem to be addressed, this research provides by far the most comprehensive evidences to the mechanism of the Dongsha Event.

Pedestal and Er profile evolution during an edge localized mode cycle at ASDEX Upgrade

The upgrade of the edge charge exchange recombination spectroscopy diagnostic at ASDEX Upgrade has enabled highly spatially resolved measurements of the impurity ion dynamics during an edge-localized mode cycle (ELM) with unprecedented temporal resolution, i.e. 65 μs. The increase of transport during an ELM induces a relaxation of the ion, electron edge gradients in impurity density and flows. Detailed characterization of the recovery of the edge temperature gradients reveals a difference in the ion and electron channel: the maximum ion temperature gradient is re-established on similar timescales as , which is faster than the recovery of . After the clamping of the maximum gradient, Ti and Te at the pedestal top continue to rise up to the next ELM while ne stays constant which means that the temperature pedestal and the resulting pedestal pressure widen until the next ELM. The edge radial electric field Er at the ELM crash is found to reduce to typical L-mode values and its maximum recovers to its pre-ELM conditions on a similar time scale as for ne and Ti. Within the uncertainties, the measurements of Er align with their neoclassical predictions for most of the ELM cycle, thus indicating that Er is dominated by collisional processes. However, between 2 and 4 ms after the ELM crash, other contributions to flow, e.g. zonal flows or ion orbit effects, could not be excluded within the uncertainties.

Anomalous electron heating effects on the E region ionosphere in TIEGCM

AbstractWe have recently implemented a new module that includes both the anomalous electron heating and the electron‐neutral cooling rate correction associated with the Farley‐Buneman Instability (FBI) in the thermosphere‐ionosphere electrodynamics global circulation model (TIEGCM). This implementation provides, for the first time, a modeling capability to describe macroscopic effects of the FBI on the ionosphere and thermosphere in the context of a first‐principle, self‐consistent model. The added heating sources primarily operate between 100 and 130 km altitude, and their magnitudes often exceed auroral precipitation heating in the TIEGCM. The induced changes in E region electron temperature in the auroral oval and polar cap by the FBI are remarkable with a maximum Te approaching 2200 K. This is about 4 times larger than the TIEGCM run without FBI heating. This investigation demonstrates how researchers can add the important effects of the FBI to magnetosphere‐ionosphere‐thermosphere models and simulators.

Effect of nature and pressure of ambient environments on the surface morphology, plasma parameters, hardness, and corrosion resistance of laser-irradiated Mg-alloy

AbstractThe influence of nature and pressure of ambient environment on the surface modification, plasma parameters, hardness, and corrosion resistance of Mg-alloy has been investigated. Nd: YAG laser (1064 nm, 10 ns, 25 mJ) at a fluence of 1.3 J cm−2 has been employed as an irradiation source. Targets of Mg-alloy were exposed in the ambient environments of argon (Ar), neon (Ne), and helium (He) at pressures ranging from 5 to 760 Torr. Scanning electron microscope has been employed to investigate the surface morphology of the irradiated targets. It reveals the formation of cavities, cones, droplets, ripples, and islands on the surface of the irradiated sample. Laser-induced breakdown spectroscopy technique was employed to measure electron temperature (Te) and electron number density (Ne) of Mg-alloy. The value of electron temperature ranges from 6628 to 12,855 K, whereas the value of electron number density varies from 5.4 × 1017 to 19.2 × 1017 cm−3. The maximum Te and Ne are observed in Ar and minimum in case of He. It was also revealed that both the surface morphology and plasma parameters are strongly dependent upon nature and pressure of environmental gases. The maxima of Te is achieved at a pressure of 10 Torr for all the three ambient environments that is, Ar, Ne, and He; whereas maxima of Ne is achieved at different pressures, that is, at 760 Torr for Ar, at 200 Torr for Ne, and at 50 Torr for He. The hardness and corrosion resistance of irradiated Mg-alloy have been explored using Vickers Micro-hardness tester and Potentio-dynamic polarization technique, respectively. It was investigated that as compared with un-irradiated target, the hardness as well as corrosion resistance of the laser-irradiated target has been increased significantly in all environments. Plasma parameters, mechanical, and electrical properties of laser-irradiated Mg-alloy have been correlated with induced surface modifications and are strongly influenced by environmental conditions.

Tellurium n-type doping of highly mismatched amorphous GaN1−xAsx alloys in plasma-assisted molecular beam epitaxy

In this paper we report our study on n-type Te doping of amorphous GaN1−xAsx layers grown by plasma-assisted molecular beam epitaxy. We have used a low temperature PbTe source as a source of tellurium. Reproducible and uniform tellurium incorporation in amorphous GaN1−xAsx layers has been successfully achieved with a maximum Te concentration of 9×1020cm−3. Tellurium incorporation resulted in n-doping of GaN1−xAsx layers with Hall carrier concentrations up to 3×1019cm−3 and mobilities of ~1cm2/Vs. The optimal growth temperature window for efficient Te doping of the amorphous GaN1−xAsx layers has been determined.