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Whistler-mode waves have been extensively observed and investigated in terrestrial space. In this study, we present the dynamic response of whistler-mode waves to different solar wind conditions in the dayside terrestrial space based on Magnetospheric Multiscale (MMS) data. Statistical results show that the occurrence rate, amplitudes, and corresponding electron temperature anisotropy of whistler-mode waves increase with P sw in the dayside terrestrial space, which is attributed to the compression of magnetic fields in these magnetosheath and outer magnetosphere. Furthermore, whistler-mode waves under the southward interplanetary magnetic fields (IMFs) show a higher occurrence rate than that under the northward IMFs, mostly corresponding to T e ⊥/ T e ∥ > 1, and have a higher occurrence rate during quasi-radial IMFs. These results present that whistler-mode waves in these magnetosheath and outer magnetosphere are also modulated by the solar wind as clearly as the inner magnetosphere. This work advanced our understanding in the solar–terrestrial interaction. [ABSTRACT FROM AUTHOR]

To investigate the effect of various notch damages at the blade tip of a pressurized rotor blade on the aerodynamic performance, the repair margin of blade tip notch damage and obtaining its spacing in the wing polish in size is explored. Based on the Rotor 37, a model of a blade with a notch depth between 0–0.3 mm and 0.3–5 mm is obtained, and the calculation model of the single-pass aerodynamic performance before and after the damage is constructed. Numerical simulations of the full 3D viscous flow field are carried out for the design and near-surge conditions, and the data are compared and analysed. The following results are obtained: the mass flow rate increases with the notch depth; the pressure boosting capacity slightly increases and then significantly decreases when the notch depth exceeds 1 mm; the stability margin is lower than 15% after the tip notch damage exceeds 0.23 mm and decreases with the notch depth; and the tip notch does not significantly affect the aerodynamic performance of the intact blade section at the height under the notch. When the notch depth exceeds 0.23 mm, the blade starts to show a near-stall trend, and when the notch depth approaches 5 mm, it demonstrates the near-stall operating condition. [ABSTRACT FROM AUTHOR]

This study presents multiphysics analyses of the electron target cooling system of the accelerator-driven system (ADS) of the Kharkiv Institute of Physics and Technology (KIPT) using MCNP and Fluent computer programs. MCNP has been used to transport electrons, gammas, and neutrons, and to calculate the energy deposition in the target materials. The MCNP mesh-tally data have been imported into Fluent by a C subroutine that has been compiled and linked to Fluent as a user-defined function. The KIPT ADS is located in Ukraine and was in operation until February 2022. The Fluent model is based on the computer-aided design files from the manufacturing process of the target assembly. The Fluent results for the reference case match very well the literature results obtained by STAR-CCM+ during the design phase. Other cases that differ from the reference one have been analyzed; in these cases, it is assumed a malfunction of the electron accelerator or of the water cooling system. The target cooling system operates normally for all the analyzed cases except when the inlet water mass flow rate is decreased. The transient analysis showed that the target cooling system can operate for 180 s with full power when the inlet water mass flow rate is decreased down by 75%. [ABSTRACT FROM AUTHOR]

To promote the industrial application of lasers in the high precision or micromachining of carbon-fibre-reinforced polymer (CFRP) composites, this work explored a compromise process strategy for both machining quality and material removal efficiency. CFRP was cut and drilled by femtosecond pulses laser with the wavelength of 1030 nm. The effects of laser processing parameters such as pulse repetition frequency, pulse energy and power on the volume ablation rate, material removal efficiency, thermal damage and kerf taper angle were explored, and the related mechanism of infrared (IR) femtosecond laser processing CFRP was discussed. The parameters combination for IR femtosecond laser processing CFRP was determined, so that the efficiency, kerf quality and mechanical properties were qualified; namely, the repetition frequency of 100 kHz and pulse energy of 40 μJ. The tensile strength of processed samples reached 519.3 MPa, which was 10.5% higher than that of drilled samples. This study can provide practical reference and theoretical basis for the large-scale application of laser processing CFRP. [ABSTRACT FROM AUTHOR]

CHF3/Ar plasma was used to etch LiTaO3 crystal by inductively coupled plasma technology. The etched crystals under different process parameters were analyzed by surface profilometer and characterized by atomic force microscopy and scanning electron microscope. It was shown that ICP power, RIE power, and total gas flow rate had similar effects on etching rate and selectivity, while Ar/(Ar + CHF3) gas ratio had opposite effects on etching rate and selectivity, with better etching rate and selectivity at the ratio of 0.2. Our work gives a fundamental instruction for the fabrication of LiTaO3 based devices. [ABSTRACT FROM AUTHOR]

Despite a growing number of observations of whistler waves in/around the reconnection diffusion region, the origin of the whistler waves in the diffusion region and their role in reconnection remain elusive. This paper investigates the whistler‐mode waves within an electron‐scale reconnecting current sheet observed by the Magnetospheric Multiscale mission on 23 December 2016. These whistlers were observed in both the electron diffusion region (EDR) and the immediate inflow region of the electron‐scale magnetic reconnection site. The dispersion relation of these whistlers is measured and compared to predictions from linear theory for the first time in these regions. The comparison shows that the field‐aligned drifting electron component critically modifies the dispersion relation of whistlers in the EDR due to the Doppler‐shift effects. We demonstrate that these whistlers propagated into the EDR from outside rather than locally excited, however, they did not provide sufficiently large anomalous dissipation in this EDR. Plain Language Summary: Whistler‐mode waves are important plasma waves in the space plasma system, which can effectively interact with electrons to exchange energy. Whistler waves are frequently observed in various areas of magnetic reconnection, for example, outflow region, separatrix region, and diffusion region. However, the nature of whistler waves in the electron diffusion region (EDR), where the magnetic field line is broken and reconnected, is still unclear. Here, we present an observation of whistler waves in the EDR and the inflow region of magnetic reconnection. These whistler waves originate from the outside and propagate into the vicinity of the reconnection site. We measured the dispersion relation of these whistler waves for the first time within these regions and compare it with the dispersion relations predicted by linear theory. The results indicate that the effects from the drift velocity of electrons play a key role in modifying the dispersion relation of these whistlers in the EDR. Additionally, we find that these whistlers did not provide effective anomalous dissipation in this EDR. These results advance our knowledge of the source and features of whistlers in the vicinity of the reconnection site. Key Points: Observations confirm that whistler waves can propagate into the electron diffusion region (EDR) from outsideThe dispersion relation of the whistler waves is measured for the first time in the EDRThe observed whistler waves contributed to negligible anomalous effects in the EDR [ABSTRACT FROM AUTHOR]

Bent Laue monochromator HEX is designed with a high-energy non-focusing X-ray monochromator for full-field imaging. The following design ideas apply to the imaging monochromator: The HEX center branch, which the monochromator serves, is white-beam compatible. The monochromator is located in the first optical enclosure with the following parameters: source to monochromator distance is 31 m; monochromator to sample distance is 73 m. Diffraction Enhanced Imaging (DEI) or Analyzer Based Imaging (ABI) uses a perfect crystal monochromator and matching analyzer to achieve sensitivity to X-ray refraction and ultra small-angle scattering on the order of 0.01 micro-radians. [Extracted from the article]

CHF3/Ar plasma was used to etch LiTaO3 crystal by inductively coupled plasmas technique. X-ray photoelectron spectroscopy was performed to investigate the etching mechanism. It was found that chemical reactions had occurred between the F plasma and the Li and Ta metal species, forming the corresponding fluorides. Some fluorides are nonvolatile, and remained on the surface during the etching period. In order to get higher etching rate, it is important to remove these metal fluorides. The combination of chemical reaction and sputtered etching was performed and could effectively remove the remaining residues. [ABSTRACT FROM AUTHOR]

Sargassum horneri (Turner) C. Agardh is a genus of brown algae and plays an important role in marine ecosystem. However, the inhabiting area of S. horneri has been decreasing sharply in China. To understand the photoacclimation and photoregulation strategies of S. horneri in responses to temperature and light, S. horneri was cultured under different temperatures [18°C (LT) and 26°C (HT)] and light intensities [60 µmol(photon) m-2 s-1 (LL) and 120 µmol(photon) m-2 s-1 (HL)] for 7 d, and then the chlorophyll a fluorescence parameters were measured. The results showed that the maximum electron transfer rate occurred at low temperature and high light (LT-HL) condition. The high temperature was the predominant factor for causing inhibition of PSII, lowering the effective quantum yield of PSII, and reducing the nonphotochemical quenching (NPQ). However, high light could improve the photoprotective ability via enhancing the NPQ. On the other hand, a strong linear relationship was observed between NPQ and the electron transport efficiency (a); the increase of NPQ could reduce the a value and avoid damage from high light stress to PSII. Therefore, S. horneri was found to be well adapted to grow under LT-HL conditions. [ABSTRACT FROM AUTHOR]

We investigate whistler‐mode waves and broadband electrostatic waves (EWs) within an ion diffusion region (IDR) at the magnetopause. The quasi‐parallel whistlers are observed in the separatrix regions associated with the electron anisotropy or loss cone, while the oblique whistlers, the Buneman‐type waves, and the oblique EWs are observed in the center of the current sheet associated with the accelerated electron or ion beams. The whistlers are linked with Buneman‐type waves by the electron Pacman distribution rather than the wave‐wave process. The accelerated cold electron beams excite the Buneman‐type instabilities and make the anisotropy or loss cone of hot electrons less apparent, which led to the conversion of the whistlers from quasi‐parallel to oblique. Additionally, the oblique EWs are associated with the ion beams produced by the multiple X‐line reconnection. These results provide a further understanding of the relation between plasma waves and plasma kinetics in the IDR. Plain Language Summary: The whistler waves and the broadband electrostatic waves are two common waves produced by magnetic reconnection in space plasma. Generally, the whistler waves have two modes, the quasi‐parallel and the oblique to the ambient magnetic field associated with different generation mechanisms. Both of them have been observed in the magnetic reconnection, but their relation is still unclear. The broadband electrostatic waves are sometimes simultaneously observed with the oblique whistlers. The relationship between them is also inconclusive. Here, we present a new view of the relation between the quasi‐parallel whistlers, the oblique whistlers, and the broadband electrostatic waves. They are linked by the evolution of electron Pacman distribution, which is composed of the hot magnetospheric population with the loss cone and the cold accelerated magnetosheath beam characteristic for magnetopause reconnection, in the reconnection diffusion region rather than the wave‐wave process. Besides, the oblique electrostatic waves associated with ion beams are observed in the diffusion region. These results advance our understanding of the relation between plasma waves and magnetic reconnection. Key Points: Large‐amplitude electromagnetic and electrostatic waves are observed in the separatrices and center of the diffusion region, respectivelyQuasi‐parallel whistlers, oblique whistlers, and Buneman‐type waves are linked via the evolution of electron Pacman distributionThe oblique broadband electrostatic waves associated with the ion beams are observed in the diffusion region [ABSTRACT FROM AUTHOR]

Two‐dimensional Hall reconnection model can explain the fast release of magnetic energy and most of its predictions have been demonstrated by in situ satellite observations. However, the three‐dimensional effect to reconnection remains poorly known. Recent numerical simulations have shown that three‐dimensional evolution is more complex than two‐dimensional in that reconnection occurs in multiple sites that are not necessarily in the primary neutral current sheet. Here, we present the first observational evidence for localized secondary reconnection at the separatrix surface of a magnetic flux rope (MFR). This secondary reconnection occurs between the axial magnetic field of the MFR, which points out‐of‐plane of the Earth's magnetopause reconnection, and the magnetospheric field. This three‐dimensional electron‐scale reconnection in the exhaust facilitates the cross‐scale energy conversion from the macro‐scale down to electron‐scale. Plain Language Summary: Magnetic reconnection releases large amounts of magnetic energy in astrophysical, space and laboratory plasmas. For the decades, the reconnection has been investigated largely based on two‐dimensional models while the three‐dimensional effect to reconnection remains poorly known. It has been shown by numerical simulation that three‐dimensional evolution, because of the freedom in the out‐of‐plane direction, is turbulent and distinct from the two‐dimension laminar reconnection in that reconnection occurs in multiple sites that are not necessarily in the primary neutral current sheet. The turbulent reconnection is characterized by the formation and interaction of multiple flux ropes, or chaotic magnetic field lines in the outflow region. Although small‐scale magnetic flux ropes and their interactions have been observed, one important missing piece is whether reconnection occurs at the region away from the neutral current sheet. Here we present the first evidence for localized secondary reconnection at the separatrix surface of the primary reconnection. This secondary reconnection occurs between the axial magnetic field of the flux rope, which points out‐of‐plane of the magnetopause reconnection, and the magnetospheric field. This three‐dimensional patchy reconnection in the exhaust facilitates the cross‐scale energy conversion from the macro‐scale down to electron‐scale and leads to a turbulent evolution of reconnection. Key Points: Three‐dimensional secondary electron‐scale reconnection was observed at the separatrix of a flux rope in the magnetosphereNew light on the destiny of flux rope from a three‐dimensional perspective: dissipation through the reconnection of the core fieldThe cross‐scale energy conversion is through the formation and dissipation of flux ropes [ABSTRACT FROM AUTHOR]

A Fe-based multi-component alloy, 60Fe-12Cr-10Mn-15Cu-3Mo, which presents higher yield stress than typical stainless steels (such as 304, 316, and 340), was used to investigate the thermal stability of irradiation-induced defects. Neutron irradiation was carried out at approximately 323 and 643 K using up to 1.3 × 10−3 and 4.5 × 10−4 dpa (displacements per atom), respectively. While no defects were accumulated at the high temperature of 643 K, single vacancies were formed after irradiation at the low temperature of 323 K to 1.3 × 10−3 dpa, and the vacancies became mobile at 423 K. As a result, vacancy clusters were formed. However, as the annealing temperature increased the size of vacancy clusters decreased. Coincidence Doppler broadening measurements indicated that Cu precipitates were the sites of vacancy cluster formation, and the recovery of vacancy clusters became prominent while annealing the irradiated sample at temperatures higher than 423 K. Recovery of vacancy clusters at 573 K, which was not a high temperature, was also observed even in the sample that was irradiated using 2.5 MeV Fe ions at room temperature to 0.6 dpa at damage peak. [ABSTRACT FROM AUTHOR]

In order to investigate the interactive effects of simulated acid rain and copper (Cu) on macroalgae, Sargassum horneri was cultured under pH of 8.2, 5.6, 4.5 and Cu concentrations of 0, 25, 100 µg L-1. Under the medium concentration of Cu, moderate pH mitigated the toxicity of Cu on S. horneri, while the low pH and high Cu concentration reduced the contents of chlorophyll (Chl) a and carotenoids. Furthermore, pH had no interaction with Cu on maximal Chl fluorescence or electron transport efficiency, while effective PSII quantum yield, maximum electron transport rate, and saturating irradiance were obviously affected by pH and Cu, and the interactive effects were significant. Additionally, with the increasing Cu concentration and decreasing pH, nonphotochemical quenching and regulated energy dissipation dropped sharply, while nonregulated energy dissipation increased. Therefore, the high concentration of Cu and low pH had synergistic effects on the photosynthetic performance and growth of S. horneri. [ABSTRACT FROM AUTHOR]

Dipolarization fronts (DFs) are important for energy conversion, particle acceleration, and flux transport in the magnetotail. The partition of energy conversion between ions and electrons and the energy dissipation at DFs are not well understood. In this paper, we present a statistical study of energy conversion and dissipation of 122 DFs observed by Magnetospheric Multiscale mission in the magnetotail. Statistically, electromagnetic energy transfers to plasma at DF. The released energy is mainly transferred to ions rather than electrons. On average, ions gain energy across the whole DF, while electrons gain energy at the leading part but lose energy at the trailing part of DFs. Joule dissipation J · (E+ve × B) can be either positive or negative at DFs, and its average value is very small. The kinetic energy dissipation parameter Pi − D does not exhibit clear signatures at the DFs; hence, it is not suitable for quantifying the energy dissipation at DF. Key Points: Statistical study of the energy conversion and dissipation at DFs observed by MMSElectromagnetic energy released at DF mainly goes to heat and accelerate ionsAverage Joule dissipation across DF is very small, and the parameter Pi − D is not suitable for quantifying the energy dissipation at DF [ABSTRACT FROM AUTHOR]

Through phase‐space analysis of Dumond diagrams for a flat Bragg crystal, a single bent Laue crystal and a monochromator consisting of double‐bent Laue crystals, this work shows that it is possible to match the flat Bragg crystal to both the single‐crystal and double‐crystal Laue monochromators. The matched system has the advantage that the phase space of the bent crystal's output beam is much larger than that of the flat crystal, making the combined system stable. Here it is suggested that such a matched system can be used at synchrotron facilities to realize X‐ray dark‐field imaging, analyzer‐based imaging and diffraction‐enhanced imaging at beamlines using double‐Laue monochromators. [ABSTRACT FROM AUTHOR]

Al doped p-type 6H silicon carbide was irradiated by low energy electrons to create primary defects. Two deep levels at EV+0.36 eV and EV+0.81 eV were created by this irradiation. Isochronal annealing study was carried out on the electron irradiated sample to investigate the annealing out of the two primary defects and the creation of thermal annealing-induced secondary defects. Four more deep hole traps (0.45, 0.56, 0.74, and 0.71 eV above the valence band) were formed during the whole annealing process up to a temperature of 1600 °C. All the electron irradiated deep level defects were annealed out after the 1600 °C annealing. [ABSTRACT FROM AUTHOR]

A model is presented in this article to investigate the dependence of effective magnetostriction of the magnetostrictive composites on the parameters of components including the elastic modulus, permeability, and volume fraction, etc. Concentrating on the two-component magnetostrictive composites and choosing the two components to be general magnetostrictive materials, this model yields, analytically, the effective magnetostriction of composites by means of the method of complex potential. In terms of the analysis of this model, the magnetostrictive composites can be roughly divided into two kinds. One kind is that the matrix material is nonmagnetic or a material with very low magnetostriction, in which the effective magnetostriction is independent of the permeability of components. Another kind is the case in which the two components have close magnetostriction, and the effective magnetostriction of the composites generally depends on the elastic and the magnetic parameters of both components and the volume fraction. Unlike the first kind of composite, in a certain range, effective magnetostriction of this kind of composite can be improved by increasing the permeability of matrix. In addition, dependence of the effective magnetostriction on the other parameters of the components has also been discussed systematically. To evaluate the accuracy of this model, comparisons are made between the theoretical values and the experimental results published in the literature, which indicate that predictions of this model agree qualitatively with the experimental data. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Magnetic holes have been widely observed in various space plasma systems. The origin of magnetic holes and their influence to background plasma are under debate. In this paper, we show a kinetic‐scale electron vortex magnetic hole in a nonideal region of an active X line, which was observed by the Magnetospheric Multiscale mission at the dayside magnetopause. Intense current and nonideal electric field in the electron frame were observed within the magnetic hole, which led to a strong energy dissipation. Thus, the electron vortex magnetic hole probably provided an additional energy dissipation channel besides the electron diffusion region adjacent to the hole. We suggest that magnetic reconnection provided favorable conditions for the formation of this kinetic‐scale magnetic hole and is an important source of magnetic holes in space plasma. Key Points: First evidence for reconnection‐driven kinetic‐scale magnetic holeThe hole was associated with an electron vortex and was observed in the vicinity of an electron diffusion regionThe hole probably provided an additional energy dissipation channel besides the electron diffusion region [ABSTRACT FROM AUTHOR]

Background Circular RNAs (circRNAs) are possible biomarkers for many diseases, but the knowledge of circRNAs in the peripheral blood mononuclear cells (PBMCs) of patients with systemic lupus erythematosus (SLE) remains limited. This study aimed to assess the expression of circRNAs in PBMCs from patients with SLE and healthy individuals by RNA sequencing (RNA-seq). Methods In total, 128 circRNAs were significantly differentially expressed including 39 upregulated and 89 downregulated circRNAs in four new-onset SLE patients compared with three healthy controls. After verification of the four candidate circRNAs in 49 patients with SLE and 37 controls using quantitative real-time polymerase chain reaction (qRT-PCR) assays, a previously undescribed circRNA with potential translation activity, circPTPN22, was selected to confirm its clinical significance. Results Bioinformatics analysis demonstrated that the parent gene of circPTPN22 was protein tyrosine phosphatase non-receptor type 22 (PTPN22), a potent regulator of T cell activation. The downregulation of circPTPN22 in patients with SLE was strongly negatively correlated with their Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores. circRNA-miRNA-mRNA co-expression network analysis indicated a correlation between circPTPN22 and the miRNAs and mRNAs related to immunological regulation including the development of SLE. Patients with higher SLEDAI scores had lower circPTPN22 expression levels, and long-term hormone treatment significantly increased circPTPN22 levels. Receiver operating characteristic curve analysis indicated that circPTPN22 has good diagnostic value for SLE. Conclusion Our data demonstrated the aberrant expression of circRNAs in patients with SLE compared with healthy controls; circPTPN22 might function as a diagnostic and disease severity indicator in SLE. [ABSTRACT FROM AUTHOR]

Highlights • Interface crack between magnetoelectroelastic and orthotropic materials is studied. • Full-field solution in the cracked bi-materials is given. • Crack propagation can either be enhanced or retarded. Abstract In this paper, an interface crack between magnetoelectroelastic and orthotropic half-spaces under anti-plane shear and in-plane electric and magnetic loadings has been studied. By using integral transform techniques the mixed boundary value problem for interface crack was reduced to the solution of singular integral equations, which can be further reduced to solving a Riemann-Hilbert problem with closed form solution. An analytic full-field solution for stresses, electric fields, magnetic fields, electric displacement and magnetic induction in the cracked bi-materials is given, and of particular interests, the analytical expression of the stresses, electric displacements and magnetic inductions along the interface has been obtained. The crack sliding displacements (CSDs) of the interface crack are provided, and it is found that the stress distributions inside the orthotropic material are dependent on the elastic stiffness of the orthotropic material. The results of the stress intensity factors indicate that the crack propagation can either be enhanced or retarded depending on the magnitude and direction of the electric and magnetic loadings. [ABSTRACT FROM AUTHOR]

Summary: Pregnant women and infants are at an increased risk of severe disease after influenza infection. Maternal immunization is a potent tool to protect both these at‐risk groups. While the primary aim of maternal influenza vaccination is to protect the mother, a secondary benefit is the transfer of protective antibodies to the infant. A recent study using the tetanus, diphtheria and acellular pertussis (Tdap) vaccine indicated that children born to mothers immunized in the second trimester of pregnancy had the highest antibody titres compared to children immunized in the third trimester. The aim of the current study was to investigate how the timing of maternal influenza immunization impacts infant antibody levels at birth. Antibody titres were assessed in maternal and cord blood samples by both immunoglobulin (Ig)G‐binding enzyme‐linked immunosorbent assay (ELISA) and haemagglutination inhibition assay (HAI). Antibody titres to the H1N1 component were significantly higher in infants born to mothers vaccinated in either the second or third trimesters than infants born to unvaccinated mothers. HAI levels in the infant were significantly lower when maternal immunization was performed less than 4 weeks before birth. These studies confirm that immunization during pregnancy increases the antibody titre in infants. Importantly, antibody levels in cord blood were significantly higher when the mother was vaccinated in either trimesters 2 or 3, although titres were significantly lower if the mother was immunized less than 4 weeks before birth. Based on these data, seasonal influenza vaccination should continue to be given in pregnancy as soon as it becomes available. Maternal immunization is a potent tool to protect pregnant women and their newborn infants against influenza. In this study we investigated the effect of different timing of influenza immunization in pregnancy on the transfer of antibody to the infant. Antibody levels in cord blood were significantly higher when the mother was vaccinated in either trimesters 2 or 3, although titres were significantly lower if the mother was immunized less than 4 weeks before birth. [ABSTRACT FROM AUTHOR]

The interest in flexible stretchable printed electronics has increased because of the wide applications, especially for wearables devices. The conventional manufacturing processes were time consuming and expensive, which led to developing of stretchable interconnects using screen printing. In this research, meander patterns of varying meander angles were designed and screen-printed on thermoplastic polyurethane substrates. Silver inks and carbon inks were used to print the circuits, which were subjected to tensile tests while their changes in resistance were measured. The electrical characteristics were utilised to determine the elastic limits of the circuits and the conditions for cyclic tests of up to 10,000 cycles. It was found that the maximum strain at break of the silver ink was 47%. Carbon ink had a higher initial resistance value and the maximum strain at break was 125%. The best stretchability was obtained at the 0° meander angle, a curing time of 30 min and curing temperature of 130 °C with oven cooling. [ABSTRACT FROM AUTHOR]

Abstract By assuming that Young's modulus and Poisson's ratio of a linearly elastic and isotropic material vary along the radial direction in a panel with a circular hole and deformed by a far field uniaxial tensile traction, we first analytically find the stress concentration factor, K , at the hole. The problem is solved by superposing solutions of two problems – one of uniform biaxial tension and the other of pure shear. The solutions of the first and the second problem are, respectively, in terms of hypergeometric functions and Frobenius series. Subsequently, we analytically study the material tailoring problem for uniform biaxial tension, and give explicit variation of Young's modulus to achieve a prespecified K. For the panel loaded by a far field uniaxial tensile traction, we show that the K can be reduced by a factor of about 8 by appropriately grading Young's modulus and Poisson's ratio in the radial direction. By plotting K versus the two inhomogeneity parameters, we solve the material tailoring problem for a panel loaded with a far field uniaxial traction. The analytical results should serve as benchmarks for verifying the accuracy of approximate/numerical solutions for an inhomogeneous panel. [ABSTRACT FROM AUTHOR]

Since many applications of YBCO tapes operate in external magnetic fields, it is necessary to investigate the magneto-angular dependence of critical current and n-values in coated conductors. In this paper, five commercial YBCO tapes with different microstructures produced by three different manufacturers are chosen. The selected samples have a width of 2.0, 4.0, 4.8, 6.0 or 12 mm, with copper, brass or stainless steel laminations. The critical current density dependence Jc(B, θ) and n-values characteristics n(B, θ) of the tapes are comprehensively measured under various magnetic fields and orientations. Afterwards, the obtained experimental data sets are successfully fitted using a novel multi-objective model which considers the material anisotropy. By using this approach, a fitting function Ic(B, θ) can always be obtained to accurately describe the experimental data, regardless of the fabrication and width differences of the superconducting tapes. Moreover, our experiment shows that when subject to different external magnetic fields, the angular dependence of n-values characteristics is directly correlated with the corresponding critical current profiles. Our results are helpful to predict the critical current of electromagnetically interacting 2G HTS wires, thereby improving the design and performance of the devices made from YBCO tapes. [ABSTRACT FROM AUTHOR]

This work investigated bonding strength of wood from pine, oak and nyatoh, glued with polyvinyl acetate and rubber-based contact adhesive, and exposed to accelerated soaking in water for 2, 4, 6, 12 and 24 hours. The bonding strength of each sample was determined using a universal testing unit. Surface roughness of the samples was also measured using a profilometer. Control samples had the highest bonding strength values for all three types of species. Soaked pine samples did not have any bonding strength for both adhesives, while the rest of the samples had bonding strength reduction. Oak samples had the highest average roughness value of 7.13 pm and the highest bonding strength in all conditions. Data from this work would provide initial information for utilisation of such species in bonding applications where possible water contact is expected. [ABSTRACT FROM AUTHOR]

In this work, we investigated how elastomeric mold properties could affect the final replication accuracy in hot roller embossing. Amorphous polyethylene terephthalate was used as the polymer substrate. It was discovered that for dense features, the elastomeric mold provided better replication results compared to a metal mold. The experimental results revealed that embossing with larger pitch sizes such as 300 and 400 µm achieved better replication accuracy than that with smaller pitch sizes such as 100 and 200 µm. The side-wall surface areas of the features on the mold affected the embossing process, resulting in different degrees of replication accuracy. [ABSTRACT FROM AUTHOR]

The brittle fracture of the weld joint at low stresses is controlled by high-strength steel characteristics and welding defects. Based on fracture mechanics, the fracture behavior of the weld-base metal interface of a high-strength steel weld joint was studied to reveal the critical locations of the latter. From tensile fracture experiments of 45 steel welded specimens, the load-displacement curve and the fracture modes of weld joints were obtained. The results indicate that the critical loads and fracture modes are influenced by the crack slope angle. The maximum load of interface fracture in weld joints is less than that of the failure in the base metal mainly related to the existence of initial defects in the weld joint. The fracture surface morphology was also detected. It is considered that the fracture surface is influenced by different fracture locations and different microstructure of the weld and base metals. In addition, the critical stress intensity factors of a weld interface crack were calculated based on the critical load and the finite element linear extrapolation method. The linear fracture assessment criteria were proposed, which will be applicable to safety evaluation for the weld joints of high-strength steel structures. [ABSTRACT FROM AUTHOR]

Low-temperature photoluminescence spectroscopy has revealed a series of features labeled S1, S2, S3 in n-type 6H-SiC after neutron and electron irradiation. Thermal annealing studies showed that the defects S1, S2, S3 disappeared at 500 °C. However, the well-known D1 center was only detected for annealing temperatures over 700 °C. This experimental observation not only indicated that the defects S1, S2, S3 were a set of primary defects and the D1 center was a kind of secondary defect, but also showed that the D1 center and the E1, E2 observed using deep level transient spectroscopy might not be the same type of defects arising from the same physical origin. [ABSTRACT FROM AUTHOR]

Some high-speed rotating micro-machines and micro-vibration devices rely on the use of whirling micro-shafts subject to the effect of gravity and magnetic fields. At present, the consequences of the interaction between the elastic deformation of such shafts and the magnetic/gravitational field effects remain unresolved. Focusing on micro-scale whirling shafts with very high torsional rigidity, this study presents a theoretical treatment grounded in the theory of micro-continuum elasticity to examine the ramification of this interaction. The differential transformation method (DTM) is used to obtain extensive numerical results for qualitative assessments of the magnetic-gravitational effects interaction on standing, hanging and horizontally positioned spinning micro-scale shafts. The influence of bearing-support flexibility on the response of the whirling micro-shaft is also considered with rotational and translational springs. The gravitational sag reduces the stability of whirling standing micro-shafts and increases that of the hanging micro-shafts. Further, for all the micro-shafts configurations investigated, the magnetic field is observed to stiffen the response of the shaft and favorably shifts the critical points of vibration of the whirling shafts forward. [ABSTRACT FROM AUTHOR]

The study revealed that loss of ductility in an amorphous Fe-alloy coating on a steel substrate composite structure was essentially prevented from occurring, following radiation with modest neutron doses of ∼2 × 10 18 n/cm 2 . At the higher neutron dose of ∼2 × 10 19 , macroscopic stress-strain analysis showed that the amorphous Fe-alloy nanostructured coating, while still amorphous, experienced radiation-induced embrittlement, no longer offering protection against ductility loss in the coating-substrate composite structure. Neutron irradiation in a corrosive environment revealed exemplary oxidation/corrosion resistance of the amorphous Fe-alloy coating, which is attributed to the formation of the Fe 2 B phase in the coating. To establish the impact of elevated temperatures on the amorphous-to-crystalline transition in the amorphous Fe-alloy, electron microscopy was carried out which confirmed the radiation-induced suppression of crystallization in the amorphous Fe-alloy nanostructured coating. [ABSTRACT FROM AUTHOR]

Tomographic reconstruction algorithms offer a means by which a tilt-series of transmission images can be combined to yield a three dimensional model of the specimen. Conventional reconstruction algorithms assume that the measured signal is a linear projection of some property, typically the density, of the material. Here we report the use of multislice simulations to investigate the extent to which this assumption is met in HAADF-STEM imaging. The use of simulations allows for a systematic survey of a range of materials and microscope parameters to inform optimal experimental design. Using this approach it is demonstrated that the imaging of amorphous materials is in good agreement with the projection assumption in most cases. Images of crystalline specimens taken along zone-axes are found to be poorly suited for conventional linear reconstruction algorithms due to channelling effects which produce enhanced intensities compared with off-axis images, and poor compliance with the projection requirement. Off-axis images are found to be suitable for reconstruction, though they do not strictly meet the linearity requirement in most cases. It is demonstrated that microscope parameters can be selected to yield improved compliance with the projection requirement. [ABSTRACT FROM AUTHOR]

Recovering waste metal without the need for remelting in solid-state recycling of metal chips can create green production. The overall process of solid-state recycling should be run at the lowest possible cost to remain competitive. High temperature and prolonged preheating time for billet's homogenization in hot extrusion to consolidate the chips conflicts with the aim of minimizing energy usage. Therefore, optimizing the effect of preheating temperature and time prior to hot extrusion is important. This study investigates the effects of preheating temperature and preheating time on the extrudates' quality. Milling chips of AA6061 were cold compacted and hot extruded through a flat-face die using preheating temperatures of 400, 500, and 550 °C for 1-6 h of preheating time. The mechanical and physical properties and microstructure of the extruded profiles were compared. The results revealed that higher acceptable strength and ductility were obtained at 500 °C with 2 h of preheating time. On top of that, temperature increase was the main criterion that results in the highest tensile strength; nevertheless, it was subjected to trade-off in ductility. The profile extruded at 500 and 550 °C had gained a close tensile strength. The study includes the prediction of the chip's welding quality through the damage evolution on the extrudate's structure. It was implemented with the help of DEFORMTM 3D finite element method (FEM) software, and the normalized Cockcroft and Latham (C & L) fracture criterion was chosen. The results of the simulations were compared and validated by the experimental results. [ABSTRACT FROM AUTHOR]

Nowadays, superconducting high field magnets are used in numerous applications due to their superior properties. High temperature superconductors (HTS) are usually used for production of circular pancake or racetrack coils. However different geometries of HTS coils might be required for some specific applications. In this study, the HTS coil wound on a rectangular frame was fully characterized in homogeneous DC background field. The study contains measurements of critical current angular dependencies. The critical current of the entire coil and two selected strands under different magnitudes and orientations of external magnetic fields are measured. The critical regions of the coil in different angular regimes are determined. This study brings better understanding of the in- field performance of HTS coils wound on frames with right-angles. [ABSTRACT FROM AUTHOR]

Engineering the electronic band structure of two-dimensional electron liquids (2DELs) confined at the surface or interface of transition metal oxides is key to unlocking their full potential. Here we describe a new approach to tailoring the electronic structure of an oxide surface 2DEL demonstrating the lateral modulation of electronic states with atomic scale precision on an unprecedented length scale comparable to the Fermi wavelength. To this end, we use pulsed laser deposition to grow anatase TiO2 films terminated by a (1 × 4) in-plane surface reconstruction. Employing photostimulated chemical surface doping we induce 2DELs with tunable carrier densities that are confined within a few TiO2 layers below the surface. Subsequent in situ angle-resolved photoemission experiments demonstrate that the (1 × 4) surface reconstruction provides a periodic lateral perturbation of the electron liquid. This causes strong backfolding of the electronic bands, opening of unidirectional gaps and a saddle point singularity in the density of states near the chemical potential. [ABSTRACT FROM AUTHOR]

Lumbar spinal surgery is most commonly performed under general anaesthesia. However, spinal anaesthesia has also been used. We aimed to systematically review the comparative evidence. We only included randomised, controlled trials in this meta-analysis and calculated the risk ratio or standardised mean difference for haemodynamics, blood loss, surgical time, analgesic requirement, nausea and/or vomiting, and length of hospital stay. Eight studies with a total of 625 patients were included. These were considered to be at high risk of bias. Compared with general anaesthesia, the risk ratio (95% CI) with spinal anaesthesia for intra-operative hypertension was 0.31 (0.15-0.64), I2 = 0% (p = 0.002); for intra-operative tachycardia 0.51 (0.30-0.84), I2 = 0% (p = 0.009); for analgesic requirement in the postanaesthesia care unit 0.32 (0.24-0.43), I2 = 0% (p < 0.0001); and for nausea/vomiting within 24 h postoperatively 0.29 (0.18-0.46), I2 = 12% (p < 0.00001). The standardised mean difference (95% CI) for hospital stay was -1.15 (-1.98 to -0.31), I2 = 89% (p = 0.007). There was no evidence of a difference in intra-operative hypotension and bradycardia, blood loss, surgical time, analgesic requirement within 24 h postoperatively, and nausea/vomiting in the postanaesthesia care unit. We conclude that spinal anaesthesia appears to offer advantages over general anaesthesia for lumbar spine surgery. [ABSTRACT FROM AUTHOR]

The demand for LCD (liquid crystal display) screens will maintain a rapid growth in the next decade. The high-speed edge-grinding process is important in this industry. One issue is the subsurface damage (SSD) induced by the edge-grinding. Glass is very sensitive to the micro-cracks of the processed surface. To investigate the SSD generated by the edge-grinding process, two grinding wheels with different grit sizes and bonding materials were employed to shape the edges of ultra-thin normal-glass panels and LCD-glass panels with 12 sets of grinding conditions. The cross-sectional microscopy, as a simple and direct assessment method, was utilized to measure the depths of subsurface cracks. It was found that bonding material, diamond concentration, and grit size imposed influences on the material removal mechanism of the edge-grinding process. The edge-grinding conducted using a wheel with grit size = 22-36 μm, diamond concentration = 100, and bonding material = resin induced little damage to the glass samples. With the smooth edge ground, the majority of the material was removed by plastic deformation. However, the subsurface damage of the LCD glass was smaller than that of the normal glass induced under the same grinding condition, and the LCD showed better machinability. The density of SSD of the LCD glass was also less than that of the normal glass. [ABSTRACT FROM AUTHOR]

Vibratory finishing has been widely used for surface polishing, burnishing, edge finishing, texturing, and cleaning with a wide variety of different media. Medium properties and their motions dominate material removal efficiency and surface treatment quality in the vibratory finishing process. In this study, medium kinematic model and movement simulation of vibratory finishing were developed. Medium motion simulation was verified through a digit video recorded by a high-speed camera. It was found that medium kinematic path line is a circular-feeding helical motion, which is determined by the angular velocity ratio between the rolling and feeding, the rotation direction, and vibratory finishing machine configuration. Material removal intensity model was further established based on the kinematic model in order to better understand the vibratory finishing process. The optimal fixing location and orientation of workpiece were obtained through the analysis of the kinematic model. Finishing experiments were further carried out for the Ti6Al4V test pieces which were fixed onto the wall of a vibratory bowl. The surface roughness, Ra values (with initial surface roughness of 1.50 μm), approached to 0.13 μm after processing time of 2.5 h and 0.10 μm after processing time of 6.0 h. Surface quality of finished test pieces has been significantly improved as compared with the existing method (i.e., loosed workpiece in the vibratory bowl), whereby the surface roughness, Ra values (with initial surface roughness of 1.50 μm), tapered off (saturated) to about 0.52 μm with the increase of processing time. [ABSTRACT FROM AUTHOR]

Naturally fermented dairy products contain a rich microbial biodiversity. This study aimed to provide an overview on the bacterial microbiota biodiversity of 85 samples, previously collected across a wide region of China, Mongolia, and Russia. Data from these 85 samples, including 55 yogurts, 18 naturally fermented yak milks, 6 koumisses, and 6 cheeses, were retrieved and collectively analyzed. The most prevalent phyla shared across samples were Firmicutes, Proteobacteria, Bacteroidetes, and Actinobacteria, which together accounted for 99% of bacterial sequences. The predominant genera were Lactobacillus, Lactococcus, Streptococcus, Acetobacter, Acinetobacter, Leuconostoc, and Macrococcus, which together corresponded to 96.63% of bacterial sequences. Further multivariate statistical analyses revealed significant differences in the microbiota structure across sample geographic origin and type. First, on the principal coordinate score plot, samples representing the 3 main sample collection regions (Russia, Xinjiang, and Tibet) were mostly located respectively in the upper left, lower right, and lower left quadrants, although slight overlapping occurred. In contrast, samples from the minor sampling areas (Inner Mongolia, Mongolia, Gansu, and Sichuan) were predominantly distributed in the lower left quadrant. These results suggest a possible association between sample geographical origin and microbiota composition. Second, bacterial microbiota structure was stratified by sample type. In particular, the microbiota of cheese was largely distinct from the other sample types due to its high abundances of Lactococcus and Streptococcus. The fermented yak milk microbiota was most like that of the yogurts. Koumiss samples had the lowest microbial diversity and richness. In conclusion, both geographic origin and sample type shape the microbial diversity of naturally fermented milk. [ABSTRACT FROM AUTHOR]

Fixed abrasive polishing has some advantages in generating good planarization surfaces with low defects. The surfaces after polishing have better uniformity, and the material removal rate is much higher than that of the traditional chemical mechanical polishing using loose abrasives. One of the most important factors that have significant effects on the uniformity of the polished surface is the pad wear profile. The pad wear profile after a long time of polishing is almost concave, and it has been challenging to create a flat surface. Therefore, there is a requirement for creating a better pad wear profile to improve quality of machined surfaces in chemical-mechanical polishing processes. In this paper, kinematic aspects of the effects of operation parameters on the pad wear profile are investigated, combining with conditioner sizes, pattern, and positions. Based on that, a new model, including new designs of the conditioner and pad, is proposed. This new model has created a convex pad wear profile instead of a concave one. According to the result of the new model, the pad shape after the conditioning process is more uniform than the old one conditioned by the old model. The result was validated by an algorithm which was validated by the experiments reported in our previous paper. [ABSTRACT FROM AUTHOR]

Previous studies suggest that ropivacaine causes the least neurotoxicity among local anaesthetics. Most data derive from a single injection of ropivacaine into the subarachnoid space. The histological changes and behavioural effects of repeated intrathecal administration have yet to be studied. We examined the possible neurotoxicity of multiple doses of intrathecal ropivacaine in rats. Rats received 0.12 ml/kg body weight ropivacaine in normal saline at concentrations of 0.25%, 0.5%, 0.75% and 1.0% at 90-minute intervals via an implanted intrathecal catheter (ID 0.12 mm, OD 0.35 mm) for 48 hours. At L3, the spinal cord and posterior roots were examined by light and electron microscopy. We performed in situ TUNEL assay to evaluate apoptosis in the spinal cord. Sensory threshold to noxious stimulation along with behavioural change were also studied. Both 0.75% and 1.0% ropivacaine induced neuronal injury characterised by infiltration of inflammatory cells, vacuolation of myelin sheaths and axons, abnormal morphology of neurons and apoptosis in the spinal cord, mainly in posterior roots and the adjacent posterior white matter Compared to controls, the percentage of maximum possible effect did not show any significant differences between the rats treated with variable concentrations of ropivacaine or tested with either heat or mechanical stimulation. As expected, the recovery time to normal ambulation was prolonged as the ropivacaine concentration was increased. Ropivacaine can induce neurotoxicity and trigger apoptosis in a dose-dependent manner after repeated intrathecal administration. Although the clinical safety profile of ropivacaine appears favourable compared with other local anaesthetics, it is possible our findings have clinical significance. [ABSTRACT FROM AUTHOR]

Marie Unna hereditary hypotrichosis ( MUHH) is a rare autosomal dominant genodermatosis characterized by coarse, wiry, twisted hair developing during early childhood, with subsequent progressive hair loss. Recently, mutations in U2 HR, an inhibitory upstream open reading frame in the 5′ untranslated region of the human hairless gene ( HR), were identified as the underlying cause of MUHH. We investigated two unrelated Chinese multigenerational families with MUHH. By sequencing U2 HR in the two families, we identified two previously reported mutations, c.1A >T (p.Met1?) and c.104A>G (p*35Wext1263*). Both these mutations cosegregated with the disease phenotype in the two families. [ABSTRACT FROM AUTHOR]

In the grinding of thin-walled and honeycomb-structured components made up of Hastelloy, undesired burrs are often created. The formed burrs negatively affect the quality of the products. Subsequent deburring increases overall manufacturing process time and cost. This work was focused on development of high-speed grinding process and grinding strategies to reduce burr size and improve ground surface quality. An electroplated Cubic Boron Nitride (CBN) wheel with miniature concave and convex asperities on its circumferential working surface was developed. Grinding performance with the designed CBN wheel was compared with a normal CBN wheel without surface asperities. Special fixtures with the function of adjusting honeycomb orientation (change of grinding direction) were purposely designed and fabricated. Design of experiment (DOE) was adopted for optimization of grinding parameters. It was found that less burr (even burr-free) grinding was achieved with the utilization of the specially designed CBN wheel with concave and convex asperities under optimal grinding conditions investigated, i.e., rotational speed of 5,000 RPM, depth of cut of 25 μm, and feed rate of 7,500 mm/min. [ABSTRACT FROM AUTHOR]

Objectives: Potential gene therapy application of single and co-expression of interleukin 1 (IL-1) receptor antagonist (IL-1Ra) and transforming growth factor-β1 (TGF-β1) to alter disease progression was investigated in an in-vivo rabbit model of osteoarthritis (OA).Method: Sixteen young adult rabbits were randomly and equally divided into four groups: blank control group, IL-1Ra transfection group, TGF-β1 transfection group, and IL-1Ra/TGF-β1 double transfection group. Histological examinations were performed to monitor disease progression after haematoxylin and eosin (H&E) staining of articular cartilage. Immunohistochemistry was used to detect IL-1Ra and TGF-β1 in synovial membrane tissues. Exogenous IL-1Ra and TGF-β1 content was assessed in joint lavage fluid using an enzyme-linked immunosorbent assay (ELISA).Results: ELISA measurements from the joint lavage fluid showed high expressions of IL-1Ra and TGF-β1 in the single and double transfection groups. Remarkably, concomitant reductions in IL-1β and tumour necrosis factor alpha (TNF-α) levels were observed in these single and double transfection groups. Radioimmunoassay (RIA)-based detection showed that IL-1β and TNF-α levels in the gene transfection groups were significantly lower compared to the blank control group, in parallel experiments. Importantly, injection of IL-1Ra and TGF-β1 expressing cartilage cells into joints led to a significant inhibition of cartilage matrix degradation. Finally, IL-1Ra and TGF-β1 expression in tissues correlated with disease reversal in the experimental group, with improved tissue architecture and collagen deposition.Conclusions: Our results reveal that both single- and double-gene transfection of IL-1Ra and TGF-β1 promote extensive repair of damaged cartilage, and double transfections showed better recovery than single transfections, suggesting that co-expression of IL-1Ra and TGF-β1 inhibits degeneration and improves repair of articular cartilage in OA. [ABSTRACT FROM AUTHOR]

In the process of mechanism creative design, structure synthesis is the primary and the most important issue. This paper proposes a systematic and automatic synthesizing method of fixed-axle gear sets by means of morphological analysis. And the process is implemented to synthesize Electrified Mechanical Transmission (EMT) schemes which are parallel hybrid electric transmission composed of fixed-axle gear sets. First, independent design parameters as well as feasibility constraints and consistency conditions are defined by analyzing the structure and functions of EMT. According to these boundary conditions, structure variables such as the quantity of components and their connection relationship are solved. Then, the scheme quantity of each structure type is synthesized. Secondly, based on the abstraction of practical mechanisms with topology models, the corresponding adjacency matrixes are derived, and they are used to filtering unqualified schemes and retrieve all potential transmission paths of the remaining schemes. These potential transmission paths are further used to find out the layout and operating mode of each scheme. Finally, all schemes satisfying the structural and functional requirements are synthesized. For example, one EMT prototype is built based on one of the final schemes found and an ICE car is modified to adapt to such transmission. Vehicle test results verify the effectiveness and feasibility of the chosen transmission scheme. [ABSTRACT FROM AUTHOR]

We investigate with large-scale molecular dynamics simulations texture evolution in nanocrystalline Cu under planar shock wave loading. Five representative initial textures are explored under varying impact strengths. On the basis of Euler angles, we perform orientation mapping and texture analysis, including orientation distribution functions, pole figures, and inverse pole figures. Shock compression induces a weak but apparent ⟨ 110 ⟩ textures in nanocrystalline Cu initially with no texture, and a ⟨ 100 ⟩ fiber texture, and an incomplete weak ⟨ 110 ⟩ texture in nanocrystalline Cu initially with a { 100 } ⟨ 100 ⟩ recrystallization texture; such texture changes can be attributed to deformation twinning and dislocation slip and traced back to grains initially with ⟨ 100 ⟩. A ⟨ 100 ⟩ texture and a { 100 } ⟨ 100 ⟩ cube texture component are induced via twinning in nanocrystalline Cu initially with the ⟨ 111 ⟩ and β fiber textures, respectively, and can be traced back to grains initially with ⟨ 111 ⟩. [ABSTRACT FROM AUTHOR]

Roll-to-roll thermal embossing is a rising trend for large area processing of micro structures. However, pile-ups are formed when micro channel patterns are fed perpendicularly to the feeding direction of the embossing. Thus, there is a need to study the pile-up formation in order to reduce it for quality embossed patterns. In this work, polymethyl methacrylate and polypropylene films are used as the polymer substrates and the pile-up formation at various embossing temperature points or under various embossing pressures in the roll-to-roll embossing process is investigated. It is discovered that for polypropylene, there is a transition temperature range. Before this range, the lead pile-up is higher than the lag pile-up, while after this temperature range, the lag pile-up is higher than the lead pile-up. For polymethyl methacrylate, the lead pile-up is higher than the lag pile-up. By using a high embossing temperature and a high embossing pressure, it is able to reduce the pile-up formation and achieve good embossed patterns. [ABSTRACT FROM AUTHOR]

Fixed abrasive chemical-mechanical polishing (CMP) is an efficient surface finishing method. The non-uniformity of substrates after polishing is one of the most interesting things in current trends in research. One of the reasons for the non-uniformity is pad wear. The pad in this polishing process has abrasive grains embedded on the surface. Researching on the pad wear will help improve the pad conditioning process to get a better pad surface. Some studies have used kinematic motion to show the correlation between the cutting path density and the pad wear. However, the effect of contact time between the conditioner's grains and the pad surface on the pad wear non-uniformity has not been integrated yet. In this research, an analytical model was established by combining of the kinematic motions and the contact time to investigate the pad wear non-uniformity. The results indicated that the cutting path density and the contact time near the pad center are more than that near the pad edge. They could be the main reasons of the non-uniformity of the pad wear. The model results showed a good agreement with experiments. [ABSTRACT FROM AUTHOR]

We report the formation of a nonmagnetic band insulator at the isopolar interface between the antiferromagnetic Mott-Hubbard insulator LaTiO3 and the antiferromagnetic charge transfer insulator LaFeO3. By density-functional theory calculations, we find that the formation of this interface state is driven by the combination of O band alignment and crystal field splitting energy of the t2g and eg bands. As a result of these two driving forces, the Fe 3d bands rearrange and electrons are transferred from Ti to Fe. This picture is supported by x-ray photoelectron spectroscopy, which confirms the rearrangement of the Fe 3d bands and reveals an unprecedented charge transfer up to 1.2 ± 0.2 e-/interface unit cell in our LaTiO3/LaFeO3 heterostructures. [ABSTRACT FROM AUTHOR]