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Improvement in thermal stability is especially important for the oxide/oxide composites, which are widely applied at high temperatures. Herein, the continuous alumina fiber reinforced alumina matrix (Al 2 O 3 /Al 2 O 3) composites were fabricated at 1200–1400 °C using Al 2 O 3 powders with a mean size of 0.6 μm. The Al 2 O 3 /Al 2 O 3 composite fabricated at 1300 °C achieved a high flexural strength of 392.9 ± 20.1 MPa and a high interlaminar shear strength of 20.6 ± 1.0 MPa. After exposure at 1000 °C for 100 h and 1400 °C for 10 min, the 1300 °C fabricated Al 2 O 3 /Al 2 O 3 composite showed no significant reduction in mechanical properties. A slight decrease in mechanical properties was observed after aging at 1200 °C for 100 h. The high strength retention after the heat treatment benefited from the coarse Al 2 O 3 powders, which could not be easily sintered at high temperatures. This work can expand the selection of the Al 2 O 3 /Al 2 O 3 composites for potential applications at service temperatures as high as 1400 °C for a short term. [ABSTRACT FROM AUTHOR]

The global urbanization process requires solving the issues of rural and poverty, and research on the coupling patterns and correlational effects of rurality and regional poverty governance change can provide references for promoting regional urban-rural integration and rural revitalization. Based on the analysis of the conceptual relationship and interaction mechanism between rurality and poverty, this paper revealed the spatio-temporal pattern evolution characteristics and correlational effects of the rurality index (RI) and poverty governance level (PGL) in 91 counties of the rocky desertification area of Yunnan-Guangxi-Guizhou (RDAYGG) in China from 2005 to 2020 by using the multi-index comprehensive evaluation, Person correlation coefficient, and fixed effects model. The results showed that (1) there are similarities and differences between rurality and poverty. The logic of rurality affecting poverty governance is that the dynamic trade-offs between the share of positive and negative rurality in a region will come to alter the local capacity for urban-rural coordinated development, and the ideal process is manifested in the weakening of negative rurality and the enhancement of positive rurality. (2) From 2005 to 2020, the RI of counties within the RDAYGG showed a pattern of continuous weakening, while the PGL showed a trend of gradual increase in the whole region, and both were holistically characterized by reverse dynamic change. (3) The regional PGL is closely related to the change of rurality. When other influencing factors remain unchanged, for every 10% reduction in the RI, the PGL will increase by about 0.4%. Future research needs to focus on crucial propositions such as the mixed turn of rurality in the new era, the construction of poverty theory in the latest stage, and the spatial-temporal coupling of rural development and poverty governance. • Governance of rurality and poverty is key to promoting global urban-rural integration and regional development. • Index systems for measuring rurality and regional poverty governance were constructed. • Spatio-temporal pattern and correlation effects of rurality and poverty governance change in the RDAYGG were investigated. • Rurality changes are negatively correlated with regional poverty governance. • Incorporating the perspective of rurality into formulating regional poverty reduction policies is a key breakthrough. [ABSTRACT FROM AUTHOR]

Abstract We have investigated two solid-state phase transformations-nitriding of the ternary alloy FeCuB ribbons and martensitic phase transformation in the FeCuBN ribbons using x-ray diffraction, Auger Electron spectroscopy, and scanning electron microscopy. We also studied the diffusion kinetics of nitrogen in FeCuB ribbons and found the activation energy of N to diffuse in the FeCuB matrix and the diffusion coefficient of N at different temperatures. We investigated the evolution of the microstructure during nitriding process and found a layered growth of iron nitride in the FeCuB matrix. Finally, the martensitic phase transformation of the FeCuBN ribbons was also optimized, and the optimizing parameters for the martensitic phase transformation of FeCuB ribbons were reported. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Primary liver cancer incidence is still on the rise at the global level. • Pronounced increases in liver cancer incidence were mostly observed in countries with high socio-demographic indexes. • Liver cancer has been alleviated in some regions due to the control of HBV and HCV infections. • HCV-related liver cancer might be an important public health issue in the near future. Background & Aims Liver cancer is a common malignant neoplasm worldwide. The etiologies for liver cancer are diverse and the incidence trends of liver cancer caused by specific etiologies are rarely studied. We therefore aimed to determine the pattern of liver cancer incidence, as well as temporal trends. Methods We collected detailed information on liver cancer etiology between 1990–2016, derived from the Global Burden of Disease study in 2016. Estimated annual percentage changes (EAPCs) in liver cancer age standardized incidence rate (ASR), by sex, region, and etiology, were calculated to quantify the temporal trends in liver cancer ASR. Results Globally, incident cases of liver cancer increased 114.0% from 471,000 in 1990 to 1,007,800 in 2016. The overall ASR increased by an average 0.34% (95% CI 0.22%–0.45%) per year in this period. The ASR of liver cancer due to hepatitis B, hepatitis C, and other causes increased between 1990 and 2016. The corresponding EAPCs were 0.22 (95% CI 0.08–0.36), 0.57 (95% CI 0.48–0.66), and 0.51 (95% CI 0.41–0.62), respectively. The ASR of liver cancer due to reported alcohol use remained stable (EAPC = 0.10, 95% CI −0.06–0.25). This increasing pattern was heterogeneous across regions and countries. The most pronounced increases were generally observed in countries with a high socio-demographic index, including the Netherlands, the UK, and the USA. Conclusions Liver cancer remains a major public health concern globally, though control of hepatitis B and C virus infections has contributed to the decreasing incidence in some regions. We observed an unfavorable trend in countries with a high socio-demographic index, suggesting that current prevention strategies should be reoriented, and much more targeted and specific strategies should be established in some countries to forestall the increase in liver cancer. Lay summary Liver cancer is a common malignant neoplasm worldwide. The incidence patterns of liver cancer caused by different etiologies varied considerably across the world. In this study, we aim to determine the pattern of liver cancer incidence as well as the temporal trends, thereby facilitating the establishment of more tailored prevention strategies for liver cancer. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) have attracted wide attention because of their unique structure and properties. However, the prepared CNTs often present agglomeration state, which destroys the excellent properties of single carbon nanotubes and seriously affects the application of carbon nanotubes. How to effectively disperse carbon nanotubes has become an urgent problem to be solved. There are many factors affecting the dispersion of carbon nanotubes. In this paper, the effects of three aspects of surfactant, ultrasonic oscillation and centrifugation on the dispersion of carbon nanotubes and fiscal policies for the development of nano high-tech industry are mainly studied. [ABSTRACT FROM AUTHOR]

Rural issues, such as land fragmentation, eco-environment destruction, industrial lag and rural hollowing, can be seen as the external manifestation of the imbalance between the supply and demand of rural land use functions. Land consolidation, by virtue of its important role in regulating rural land use functions, has been proven to be multifunctional and endowed with the connotation of relieving rural issues and promoting rural development. This paper theoretically and practically explored the modes of rural development promoted by land consolidation from the perspective of land use multifunctionality for the first time and discussed its internal mechanisms. Results showed that by changing the type and intensity of rural land use functions, land consolidation can exert important influences on industrial structure, living conditions, ecological environment, and cultural construction, thereby contributing to rural development. Although the modes of rural vitalisation promoted by land consolidation from rural land use functions can be divided into intensity-adjustment mode and type-conversion mode, these two modes in practice often coexist or interconvert as the research scale changes. The intensity-adjustment mode in Jinzhuang Village that far from a megacity is largely influenced by the bottom-up forces and market demands, while the type-conversion mode in Dongheng Village that near to a megacity is largely the result of the joint effect of the position advantage, policy, and local industrial foundation. Lessons learned and policy recommendations were proposed in light of these two case studies. These findings will provide new insight into micro-level land use for other rural areas in China and even other developing countries to address rural issues and facilitate urban-rural development. [ABSTRACT FROM AUTHOR]

An investigation of the influence of the magnetic field induced by electrostatic discharge (ESD) current on magnetic tunnel junction (MTJ) device is presented in the paper. The transient magnetic field generated by the ESD current is not considered in the traditional CMOS ESD protection strategy, which may be a reason of the degradation of the performance and the robustness of STT-MRAM. An ESD protection circuit of STT-MRAM is proposed in the paper, including the diode-based ESD devices, the filter circuit and the power clamp. Based on the waveform analysis of the three ESD standard test models, including HBM, MM and CDM, a filter circuit is added in the ESD device to decrease the influence of the high frequency components on the magnetic device. The diode-based ESD devices are integrated in the ESD structure, which is used for the ESD window of STT-MRAM for its low operating voltage. Based on the operation mechanism of the STT-MRAM, its ESD window allows a low operating voltage, thus the diode-based devices are chosen to be integrated in the ESD device. The distribution and magnitude of the magnetic field are studied in the paper. The results show that the ESD protection circuit of STT-MRAM can effectively suppress the magnetic field generated by the ESD current, hence increasing the stability of STT-MRAM. Under the influence of the HBM, MM and CDM events, the ESD disturbance probability of the MTJ device are 2.0 × 10−12, 5.8 × 10−9 and 1.1 × 10−12 respectively. The influence of the memory density and the distance between pads and memory array are also investigated in this paper. The ESD protection strategy proposed in the paper can be adopted for the future high performance STT-MRAM. • The data stored in the MTJs can be destroyed by the induced magnetic field of ESD. • The influence of different ESD standard test models on MTJs have been studied. • The magnetic field and duration time of ESD events cause the magnetic reversal. [ABSTRACT FROM AUTHOR]

Abstract: The rhenium (I) complex [Re(CH3CN)3Br2(NO)] catalyzes the homogeneous hydrosilylation of a variety of substituted acrylonitriles, which were converted into the corresponding silyl-substituted alkanes with high regioselectivity of up to 94%. The products were analyzed by 1H NMR and GC–MS. A rhenium specific mechanism is proposed for the hydrosilylation of olefins. [Copyright &y& Elsevier]

Abstract: Composite films of whey protein isolate and TiO2 are formed through three simultaneous processes, i.e., the self-assembly of protein–protein, TiO2–TiO2, and the association of protein–TiO2. All the processes could be controlled by adjusting TiO2 concentration in the blended system. The self-assembly of protein–protein molecules constituted the main network of the composite film. A low TiO2 concentration (<0.25%) dispersed the TiO2 nanoparticles in the protein matrix, reinforced the association of protein–TiO2, reduced the ability of UVC absorption, and promoted the fluorescence and tensile strength of the composite films. In contrast, a high TiO2 concentration (>0.25%) enhanced the self-assembly of TiO2–TiO2 nanoparticles, brought fluorescent quenching, and produced a decline of the tensile strength and water vapor permeability. The transmittance of the visible, UVA, and UVB lights showed a first order exponential decay relative to the TiO2 concentration. [Copyright &y& Elsevier]

As a new clean renewable energy, Perovskite solar cells (PSC) has become a research hotspot. The multi-step diffusion method can effectively control the composition and proportion of the precursor liquid, regulate the crystallization process and the final morphology of the perovskite film, thereby obtaining a smooth and dense high-quality perovskite film; The introduction of micro-Mg element makes the Fermi energy level of TiO 2 electron transport layer move up, enhances conductivity, and reduces surface defect states. Correspondingly, after Mg doping, the series resistance of planar perovskite battery decreases, the electron transmission speed becomes faster, and the charge collection efficiency is improved under high bias voltage; In the process of deposition of perovskite film by one-step inverse solvent method, polystyrene (PS) is introduced to cover the surface of polycrystalline perovskite film and fill the grain boundary to form a protective layer covering single grain. On the one hand, PS coating can effectively inhibit the volatilization and phase separation of organic components in perovskite films at high temperature, and maintain the stability of film components and phase, on the other hand, PS coating can effectively prevent the corrosion of perovskite film by water, and improve the moisture stability and self-repair ability of the film. In addition, since the self-adhesive porous carbon has good flexibility, compressibility, and adhesion to the electrode, it can be applied to perovskite solar cells. After the pressure is transferred, the carbon counter electrode can form an excellent interface contact with the hole transport layer, which promote the interface charge extraction and solve the interface contact problem existing in carbon-based perovskite batteries for a long time. The purpose of the paper is to provide the basis for exploring the technology of PSCs preparation on a large scale. [ABSTRACT FROM AUTHOR]

The current economic growth model has changed from efficiency development to innovation development. Ecological environment and other problems are still very prominent, the industry is lack of close integration, universities and scientific research institutions lack a sound science and technology service system. The purpose of this study is to explore the functions of eco-innovation ecosystem based on smart city blockchain, put forward relevant policy recommendations, and provide theoretical and practical guidance for the development of an innovation ecosystem. Through the methods of network survey, macro cluster analysis and typical case analysis, present study analyzes the development of derivative products and the research status of an innovation ecosystem. Blockchain can be regarded as a trusted distributed database. Four core mechanisms, namely P2P network communication mechanism, blockchain account book storage mechanism, password mechanism and consensus mechanismare used to ensure the distributed, tamper-proof and non-repudiation characteristics of the system, which makes the blockchain system "honest" and "transparent". It has the characteristics of a wide range, cross-subject, high efficiency and low cost in application. Taking the city as an example, this paper investigates the development of the green building industry and the relationship between the innovation ecosystem. The results showed that the α coefficient reliability index of all variables was above 0.8 in terms of ecological reliability and validity, which proved that all the scales in this study had good reliability, KM0 values were more than 0.7, and the degree of freedom was high, and all the scales had high convergence validity. Among the research objects associated with the ecosystem, "technological innovation" accounts for the largest proportion of 28% in the region, and the lowest proportion is 5% of high-tech enterprises. [ABSTRACT FROM AUTHOR]

• An insole-like wearable gait tracking device was used for collecting quantitative gait features. • A supervised dimension reduction method was proposed for summarizing the quantitative gait pattern associated with cerebral small vessel disease. • People with the identified gait pattern had a 25 % higher risk of a high CSVD burden. • Our model provides insights into the underlying neurobiological mechanisms and can help to identify CSVD patients in older adults. Sensor-based wearable devices help to obtain a wide range of quantitative gait parameters, which provides sufficient data to investigate disease-specific gait patterns. Although cerebral small vessel disease (CSVD) plays a significant role in gait impairment, the specific gait pattern associated with a high burden of CSVD remains to be explored. We analyzed the gait pattern related to high CSVD burden from 720 participants (aged 55–65 years, 42.5 % male) free of neurological disease in the Taizhou Imaging Study. All participants underwent detailed quantitative gait assessments (obtained from an insole-like wearable gait tracking device) and brain magnetic resonance imaging examinations. Thirty-three gait parameters were summarized into five gait domains. Sparse sliced inverse regression was developed to extract the gait pattern related to high CSVD burden. The specific gait pattern derived from several gait domains (i.e., angles, phases, variability, and spatio-temporal) was significantly associated with the CSVD burden (OR=1.250, 95 % CI: 1.011–1.546). The gait pattern indicates that people with a high CSVD burden were prone to have smaller gait angles, more stance time, more double support time, larger gait variability, and slower gait velocity. Furthermore, people with this gait pattern had a 25 % higher risk of a high CSVD burden. We established a more stable and disease-specific quantitative gait pattern related to high CSVD burden, which is prone to facilitate the identification of individuals with high CSVD burden among the community residents or the general population. [ABSTRACT FROM AUTHOR]

Unhealthy sleep behaviors are associated with higher risks of osteoporosis (OP), while prospective evidence is limited. This study aimed to prospectively investigate this association, quantify the attributable burden of OP incidence reduction due to unhealthy sleep behaviors, and explore potential modifications by genetic risk factors. This longitudinal cohort study was conducted utilizing data from the UK Biobank, comprising 293,164 participants initially free of OP and with requisite sleep behaviors data at baseline. We followed the participants after recruitment until November 30, 2022, to ascertain incident OP. We assessed the associations of five sleep behaviors including sleep duration, chronotype, insomnia, daytime napping, and morning wake-up difficulties, as well as sleep behavior patterns identified based on the above sleep behaviors, with the risk of OP, using Cox models adjusted for multiple confounders. The analyses were then performed separately among individuals with different OP susceptibility, indexed by standard polygenetic risk scores(PRS) for OP. Our secondary outcome was OP with pathologic fracture. Subgroup and sensitivity analyses were performed. Additionally, attributable risk percent in the exposed population (AR%) and population attributable fraction (PAF) of sleep behaviors were calculated. Over a median follow-up of 13.7 years, 8253 new-onset OP cases were documented. Unhealthy sleep behaviors, such as long or short sleep duration, insomnia, daytime napping, morning wake-up difficulties, and unhealthy sleep patterns, were associated with elevated risks of OP (HRs ranging from 1.14 to 1.46, all P -value <0.001) compared to healthy sleep behaviors. Similar associations were observed for OP with pathologic fractures. Insomnia exhibited the largest AR% of 39.98 % (95%CI: 36.46, 43.31) and PAF of 33.25 % (95%CI: 30.00, 36.34) among healthy sleep patterns and components. A statistically significant multiplicative interaction was noted between sleep behaviors and OP PRS on OP risk (all P -interaction <0.001). Four unhealthy sleep behaviors and sleep behavior patterns were associated to increased OP risk, with insomnia contributing the most to OP incidence, while genetic risk for OP modified this association. These findings underscore the crucial role of adhering to healthy sleep behaviors for effective OP prevention. • Unhealthy sleep behaviors were associated with higher risks of osteoporosis. • Insomnia's attributable risk for osteoporosis was the highest among sleep behaviors. • Genetic risk modified the association between sleep behaviors and osteoporosis. [ABSTRACT FROM AUTHOR]

Abstract: A highly effective, economical, and environmentally friendly method using of CAN as oxidant and water as solvent for oxidative coupling of N,N-dialkylarylamines was reported. [Copyright &y& Elsevier]

Molybdenum disulfide (MoS 2) 2D-material is considered as one of potential candidates for next generation optoelectronic devices due to its tunable bandgap, relatively high carrier mobility, and good light absorption, etc. From the perspective of circuit simulation and system verification, an equivalent circuit model of MoS 2 /p-Si photodiode is required. In the paper, the optical response and the carrier transmission process of MoS 2 /p-Si photodiode are analyzed theoretically. A SPICE (Simulation Program with Integrated Circuit Emphasis) equivalent circuit model of MoS 2 /p-Si photodiode is proposed, which can be used to simulate the photoelectric characteristics of the 2D device. Based on the established SPICE model of MoS 2 /p-Si photodiode, the simulation results are consistent with the experimental results of MoS 2 /p-Si photodiode devices. The trans -impedance amplifier (TIA) is designed for MoS 2 /p-Si photodiode, and the set-up SPICE model is used to verify the designed TIA circuit. It shows that the SPICE model has potential application for the simulation of the opto-electrical system including the cutting-edge 2-D photo diode. [ABSTRACT FROM AUTHOR]

Monolithic CMOS sensor Particulate matter (PM) pollution in the air seriously endangers human health. The concentration of PM becomes an important indicator of the air quality. Traditional PM detector is generally based on MCU system, in which an embedded algorithm is used for counting the number of the scattered pulses. In the paper, a monolithic light scattering particle CMOS sensor is proposed and designed. The novel PM sensor IC, which combines the photometer method with CMOS circuit, can replace the traditional embedded system, with the benefits of high speed, high precision while low cost. The designed sensor shows the detection speed less than 2 μs, the detection error less than 0.01 mg/m3, and the overall layout area less than 1 mm2. The novel particle CMOS sensor proposed in this paper shows rapid and high-precision detection, while also reducing the manufacturing cost. It can be applied widely in the particle sensing scenarios, including the air pollution and water quality checking, etc.. [ABSTRACT FROM AUTHOR]

Highlights • A macro device model of SBD in 22 nm CMOS node is developed based on the actual device structure. • A novel iterative algorithm is employed during the model parameter extraction. • The developed SBD model can accurately reflect the DC and RF characteristics of the 22 nm device. • The iterative algorithm proposed in this paper is suitable for the SBD devices below 22 nm node. Abstract RF Schottky Barrier Diode (SBD) device can be compatible with deep submicron CMOS process, which is a research edge-cutting technology in the field of microelectronics. An accurate device model is highly required by the relevant circuit simulation work. In this paper, a macro device model of SBD in 22 nm CMOS node is developed based on the actual device structure. To increase its accuracy, a novel iterative algorithm is employed during the model parameter extraction. The simulation results are consistent with experimental data in frequency range from 10 MHz to 10 GHz, indicating that the developed SBD model can accurately reflect the DC and RF characteristics of the 22 nm device. Moreover, the application of the developed RF SBD device model is verified based on RF energy harvesting circuit in terms of the output voltage and efficiency, showing the feasibility of the developed SBD model in RF integrated circuit. [ABSTRACT FROM AUTHOR]

In order to ensure the consistency of the fabricated devices in batches, calibration is required on CMOS temperature sensor before delivery to compensate the tracking errors of the devices. In the paper, a wafer-level three-step calibration technique for BJT-based CMOS temperature sensor is proposed and fabricated based on TSMC 180-nm-BCD technology. The calibration approach is based on the wafer level, with the simplified calibration process. The strategy of the fuse burning directly maps with the proposed three-step calibration approach. The technique shows encouraging results in removing the error band of the sensor response caused by processing variations in batch fabrication. The calibrated sensor can realize an inaccuracy (±3δ) within ±0.3 °C from −40 °C to 125 °C. The temperature sensor with the calibration module in the paper has great potential application in mobile phones, battery management, disk drives and other fields, etc.. • The technique can effectively reduce the error caused by process variations. • The strategy of the fuse burning directly maps with the calibration approach. • The chip is calibrated during the wafer level test based on probe station. • The technique can realize an inaccuracy (±3δ) within ±0.3 °C from −40 °C to 125 °C. [ABSTRACT FROM AUTHOR]

To optimize nonlinearity and temperature drift of silicon piezoresistive pressure sensor, novel calibration algorithm based on Pade approximation is adopted in the paper. The output data of the pressure sensor is processed by the novel algorithm to remove the influences of the cross-sensitivity and the unexpected jump points. High accuracy up to 0.01% FS can be achieved based on the algorithm. Compared with the other published algorithms, the proposed algorithm shows the merits of high accuracy, less memory consumption, and low cost. The algorithm can have potential application in the field of the intelligent sensor with the requirement of high output accuracy. [Display omitted] • A calibration algorithm based on Pade approximation is proposed to optimize the output of silicon piezoresistive pressure sensor, which greatly reduces the computational effort and cost while ensuring high accuracy. • The whole calibration process for silicon piezoresistive pressure sensor is optimized in the paper. • The strategy of Pre-processing Pade is suitable not only on the silicon pressure sensor, but also on the other sensors which need to be calibrated to get rid of the environment influence and the process variations. [ABSTRACT FROM AUTHOR]

Abstract: A highly regioselective and inexpensive nitration of N,N-dialkylanilines by cerium(IV) ammonium nitrate (CAN) in acetonitrile under room temperature to yield p-nitryl-N,N-dialkylanilines in good yields was reported. [Copyright &y& Elsevier]

Grignard reagents undergo Michael addition reactions to methyl 2-halogenoacrylate compounds to afford polysubstituted cyclopropane in high yields. [Copyright &y& Elsevier]

Abstract: Reactions of low oxidation state rhenium–nitrosyl complexes with polyamine ligands have been examined. Rhenium(II)–nitrosyl complexes gave an array of unstable products that were difficult to isolate cleanly. The rhenium(I)–nitrosyl complex [ReBr2(NO)(NCMe)3] gave multiple products which were more easily isolated. The major product from the reaction of [ReBr2(NO)(NCMe)3] with the potentially pentadentate ligand N1,N1,N2-tris(2-pyridinylmethyl)-1,2 ethanediamine was the dicationic species [Re(NO)(N5)]2+, which was isolated as the bis-tetraphenylborate salt. The other major product [ReBr2(NO)(NCMe){py-CH2NH∼CH2CH2N(CH2-py)2}], was separated from a number of other neutral species via chromatography. This species contains the same potentially pentadentate ligand, only here it is coordinated through only two of its amine functional groups. Left dangling is the secondary amine and both of its pyridyl groups. Both amine complexes are diamagnetic and both display their respective parent ions in the ESI(+) mass spectra. The dication [Re(NO)(N5)]2+ shows its half mass parent peak at 275 m/z while [ReBr2(NO)(NCMe){py-CH2NH∼CH2CH2N(CH2-py)2}] shows its parent peak at 751 m/z. The infrared spectrum of [ReBr2(NO)(NCMe){py-CH2NH∼CH2CH2N(CH2-py)2}] displays its ν(N O) at 1676cm−1. And the infrared spectrum of [Re(NO)(N5)](BPh4)2 displays its ν(N O) at 1714cm−1. [Copyright &y& Elsevier]

We have combined radio frequency (RF) plasma with hot filament (HF) chemical vapor deposition (CVD) together to investigate diamond growth. By modifying the conventional RF apparatus and tungsten arrangement in RF system, we systematically investigated the process of nucleation, interlayer formation and growth by atom force microscopy (AFM), X-ray diffraction (XRD) and Raman spectra. The experimental results showed that at low substrate temperature, nano-crystal diamond and other non-diamond carbons formed. The interface between the film and the substrate contained four components: SiC, tungsten (W), W/WC or W2C, W–δ-WB and W/Si2W. High-quality diamond film can only be prepared at Ts>700 °C by RF+HF-CVD and the contamination from tungsten filaments has been remarkably reduced by pre-heating the filament in CH4+H2 atmosphere and placing it as near the upper electrode as possible. Furthermore, large area diamond film can be easily synthesized by HF+RF-CVD method, which has more advantages than other methods. [Copyright &y& Elsevier]

Abstract: Fe (001) thin films with different crystal lattice were epitaxially grown on single crystal MgO substrates under the various sputtering pressures. It is found in this paper that the tetragonality and magnetic anisotropy of Fe thin film is tuned by varying the working sputtering pressures. The tunability of the crystal lattice and the magnetic anisotropy of Fe films were characterized by X-ray reflectivity, X-ray diffraction and vibrating sample magnetometer. The tunable structure and magnetic properties of Fe thin films may attribute to the rearrangement of Fe atoms on MgO substrate induced by controlling the atomic kinetic energy under different sputtering pressure. [Copyright &y& Elsevier]

• Considered the temperature rise of MTJ in parallel state and anti-parallel state. • Considered the TDDB model in parallel and anti-parallel states. • Considered self-heating effects in the TDDB model. Spin-transfer torque magnetic random access memory (STT-MRAM) is one of the most promising candidates for "universal memory" with the ultra-fast access speed, radiation resistance and theoretically unlimited endurance. However, there are many practical aspects that could degrade the life-time of STT-MRAM. In this paper, degradation on the life-time of the STT-MTJ device is observed experimentally, which is attributed to the so-called "self-heating effect" of the device. Simulation on the device is conducted on the self-heating effect to obtain the internal temperature inside the device. The self-heating effect of the STT-MTJ device is analyzed and its influence on the life-time degradation of the STT-MTJ is included in the time dependent dielectric breakdown model (TDDB, 1/E model). This inclusion should improve the accuracy of the estimation on the life-time. [ABSTRACT FROM AUTHOR]