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High entropy alloys (HEAs), which is at the expense of high cost compared to traditional alloy, should not be confined to the mechanical properties, but should be employed to devise a novel combination with unique functional and mechanical performances. In this work, high entropy alloy nitride (HEAN) is utilized as a novel double absorption layer to improve solar absorption in the high temperature solar selective absorbing coatings (SSACs). Our primary motivation is to lower thermal emittance (e) and enhance solar absorptance (α). In order to realize this goal, coating design (CODE) software is employed to design and optimize the proposed HEAN based SSACs using appropriate dielectric function model. The ultimate as-deposited coating shows good optical properties with a high α value of 0.965 and a low e value of 0.086 (at 82 °C). The estimate of thermal stability tests indicates that HEAN based SSACs has the ability to resist instability in high working temperature, which keeps good optical properties (α = 0.925, e = 0.070) after annealing at 600 °C for 10 h.

Solar selective absorber coatings (SSACs), with the characteristics of efficient harvesting and conversion of solar energy into the heat work fluid, are considered to be one of the key components f...

Recent advances in high-entropy alloys have spurred many breakthroughs in the fields of high-temperature materials and optical materials and they provide incredible application potentialities for photothermal conversion systems. Solar-selective absorbers (SSAs), as key components, play a vital role in photothermal conversion efficiency and service life. The most pressing problem with SSAs is their inconsistent optical performance, an instability constraint induced by thermal stress. A feasible method of improving performance stability is the introduction of high-entropy materials, such as high-entropy alloy nitrides. In this study, enabled by an intrinsic MoTaTiCrN absorption layer, the solar configuration achieves greatly enhanced, exceptional thermotolerance and optical properties, leading to the formation of a scalable, highly efficient, and cost-effective structure. Computational and experimental approaches are employed to achieve optimum preparation parameters for thicknesses and constituents. The crystal structure of high-entropy ceramic MoTaTiCrN is fully investigated, including thickness-dependent crystal nucleation. High-temperature and long-term thermal stability tests demonstrate that our proposed SSA is mechanically robust and chemically stable. Moreover, a low thermal emittance (15.86%) at 500 °C promotes the photothermal conversion efficiency. In addition, due to the exceptional spectral selectivity (α/ε = 92.3/6.5%), thermal robustness (550 °C for 168 h), and photothermal conversion efficiency (86.9% at 550 °C under 100 sun), it is possible for our proposed SSA to enhance the practical realization of large-area photothermal conversion applications, especially for concentrated solar power systems.

The most recent advances in high-entropy materials provide impetus for the development of high-performance materials, simultaneously providing high-temperature robustness and excellent functional properties owing to the high configurational entropy and distorted lattices. Thus, in this work, double-layer high-entropy alloy nitride HfNbTaTiZrN with a well-designed metal content gradient is employed to fabricate a solar selective absorber coating (SSAC). We extensively investigated whether the coating meets the definition of a high-entropy material from the points of elemental analysis and phase structure, combined with thermodynamic calculation. Remarkably, the new, tailored SSAC exhibits an exceptionally high solar absorptance (α = 96%) and a suppressed thermal emittance (e = 8.2%) at 82 °C and omnidirectional absorption. Investigations of the long-term thermal stability indicate that the HfNbTaTiZrN-based SSAC due to the entropy-driven structural stabilization could endure heat treatment at 600 °C for 168 h, retaining a performance criterion (PC) value less than 0.05, which implies the feasibility of practical applications. More importantly, the photothermal conversion efficiency (η), which is utilized to quantitatively evaluate the performance at elevated temperatures, reaches 90.1% at a working temperature of 550 °C under 100 suns, and even after annealing at 600 °C for 168 h, the efficiency drop is still less than 5%. Overall, the combination of thermal robustness and photothermal conversion efficiency at working temperatures less than 600 °C provides significant potential to maximize solar energy harvesting and pioneers an opportunity to explore simultaneous multifunctional applications of high-entropy alloys.

The functional application of high entropy alloys, which emerge as a novel multi-principal component alloy, has been constantly expanding in the field of solar photothermal harvesting from optical materials to high temperature materials due to their excellent properties. A solar spectrally selective absorbing coating requires such materials that show not only outstanding optical properties but also prominent thermal stability. It is desirable but challenging to fabricate high performance solar absorbing coatings. A prospective strategy for the preparation of solar absorbing coatings is the introduction of high entropy alloys. In this work, we have developed a simple, cost-conscious, scalable and highly efficient solar selective absorbing coating using a single layer high entropy nitride AlCrTaTiZrN by choosing appropriate elemental compositions. The as-deposited coatings show an outstanding spectral selectivity of α/e = 92.8%/5.1% or 91.6%/5.1%. High temperature thermal stability tests are performed in depth, indicating that the coating could endure annealing treatment at 800 °C for 2 h with insignificant reflectance spectrum variation. A prolonged period of thermal stability characterization presents that this coating could maintain good optical performance after annealing at 650 °C for 300 h. Furthermore, high temperature thermal emittance can be suppressed to as low as 15.4% at 600 °C, which contributes to the state-of-the-art photothermal conversion efficiency under 100 suns (87.7% at 600 °C, and 84.6% at 650 °C). Overall, the high entropy nitride AlCrTaTiZrN based coating contributes to good thermal stability and optical properties, showing great potential for extensive applications in solar energy harvesting.

With the rapid advance of science and technology, it is essential to research and develop new intrinsic solar absorber coatings with the simple production process and excellent photo-thermal conversion efficiency. Herein, we have developed a novel AlCrMoTaTiN intrinsic absorber layer by radio frequency (RF) reactive sputtering method via adjusting the deposition time and the flow rate of N2. The AlCrMoTaTiN intrinsic absorber layer exhibits a high absorptance of 0.752 and a low emittance of 0.074 at 82 °C. The AlCrMoTaTiN/Al2O3 solar absorber coating is deposited by using Al2O3 works as an anti-reflective layer and the spectral selectivity (α/e) is 0.929/0.082. This coating also possesses a good thermal stability, which can be stabilized at 300 °C in air and 500 °C in vacuum for 2 h, respectively. In addition, a prolonged period of thermal stability characterization is carried out, which indicates that this coating could keep good optical performance after annealing at 600 °C for 100 h. The corresponding failure mechanism is obtained by analyzing the Raman spectroscopy and XRD. Obviously, the AlCrMoTaTiN/Al2O3 solar absorber coating has a broad application prospect in large-scale and efficient industrial production.

The aim of the present study was to explore the roles and possible molecular mechanism of the alleviating effect of sevoflurane pre‑treatment on the extracorporeal circulation and to investigate the possible involvement of the Toll‑like receptor (TLR3) signaling pathway. A total of 64 male Sprague Dawley rats were randomly divided into three groups: The sham operation group (H group; n=8), cardiopulmonary bypass (CPB) group (C group; n=24) and sevoflurane pre‑conditioning group (S group; n=32). The C group was subjected to tracheal intubation and mechanical ventilation, vessel puncture and catheter placement in the right femoral artery and right internal jugular vein, while no CPB was performed in the H group. The S group was pre‑treated with 2.4% sevoflurane for 1 h prior to establishing the CPB model. The CPB in the C and S groups was performed for 1 h. Blood of the rats was analyzed and clinical parameters were detected prior to, during and at various time‑points after CPB. In addition, eight rats from the C and S groups each were sacrificed at these time‑points and brain tissue samples were analyzed. The levels of the brain damage‑specific protein S100‑β as well as IL‑6 and IFN‑β in the serum were detected by ELISA; furthermore, the expression levels of TLR3 and TIR‑domain‑containing adapter‑inducing interferon‑β (TRIF) in the left hippocampus were assessed by ELISA and/or western blot analysis. The right hippocampus was assessed for neuronal apoptosis by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. The mean arterial pressure, heart rate and hematocrit were significantly decreased following CPB (P

With the Internet expanding quickly and there being a tremendous underlying market for digital content distributing, it brings a new technology that protects digital content from pirating and destroying--digital rights management (DRM),DRM not only protects content by encrypting, but also protects the content creator and owners rights and interests. The article primarily studies the multimedia courseware DRM in the distance network learning system. It firstly introduces the DRM based theory, then presents a DRM structure model and functional model, which is very important for the ulterior development.

The fuzzy adaptive integral sliding mode control is used, take advantage of sliding mode switching surface weaken the steady-state error and improve robust performance and the precision of steady-state of single maglev guiding system. the output of fuzzy adaptive controller is used to replace the output of switch control for the chattering problem of sliding mode control, and the adaptive control is introduced to estimate and adjust the fuzzy and clear gravity center value. Simulation results show that system achieves good performance with strong robustness.

For external disturbances and parameter perturbation problem of Electromagnetic guiding system, the adaptive sliding mode control method is used, take advantage of sliding mode switching surface eliminate the steady-state error and increase the precision at steady-state and robust performance of single electromagnetic guiding system. Matlab Simulation results show that the proposed control strategy shows good tracking performance and strong robustness

Olympic torches are the fantastic combination of successful design, appropriate materials and optimum processing which are the basic concept concepts in the major of Materials science and engineering. London Olympic torch was designed to be a three-sided pyramidal in shape, reflecting the features of the Olympic host country and the implication of designers. The material of Olympic torch selected aluminum alloys with a lightweight, high-strength, low thermal conductivity and environmentally friendly recycle; if low weight and high strength are key criteria for the torch, perhaps we can look forward to the incorporation of grapheme in the 2016 Olympic Games torch. The processing of Olympic torch involved laser cutting for 8000 holes and physical vapor deposition for gold-colored titanium nitride film on the surface of the aluminum plates, which embodied the best manufacturing route and the host country's technological capabilities.

Objective To investigate the association between birth defects and dietary nutrient intake in a high risk area of China. Methods A dietary survey was performed and serum folic acid was measured in women whose pregnancy was affected by neural tube defects (NTDs) or unaffected by any birth defects (BDs) in Zhongyang and Jiaokou Counties in Shanxi Province of China. Results The local average consumption of foods including dark green vegetables, fruits, fat and meat, and nutrient intake ( e.g. energy, protein, retinol, riboflavin, vitamin E, and selenium) were lower than the national average level. In women of childbearing age, these regions, the intake of nutrients was much lower than the recommended nutrient intake (9%-77%). The case-control dietary nutrition study of women whose pregnancy was affected by BDs (including NTDs and congenital heart defects) demonstrated that, in early pregnancy, adequate nutrition ( i.e. eating meat, fresh vegetables, fruit more than once a week) was a protective factor, while eating germinated potatoes was a risk factor. The geometrical mean (p5-p95) of serum folic acid in women with NTD birth defects was 9.6 nmol/L (3.6, 23.03), which was significantly lower than that in normal women (14.03 nmol/L). Conclusion Women of childbearing age in the two counties of Shanxi Province, China, have a marked insufficient intake of some nutrients, especially folic acid, zinc, vitamins A and B12. This nutrient deficiency may be an important risk factor for the high prevalence of birth defects in these regions. Therefore, adequate dietary nutrition in early pregnancy can prevent BDs.

Background Metabolic syndrome (MetSyn) increases the incidence of cardiovascular disease. Information on changes in prevalence of MetSyn in developing countries is limited. This study aims to compare MetSyn prevalence and its associated vascular risk over the period between 2002 and 2010 in a population which has had the world’s fastest economic development over the past three decades. Methods Two health surveys were conducted by using the multistage cluster random sampling method in a Chinese population of 85 million in southern China. The participants received a full medical check-up, including measurement of blood pressure (BP), obesity indices, fasting lipids and glucose levels. Data describing socio-economic status and lifestyle factors were also collected through interview. Metabolic syndrome was defined in accordance with the International Diabetes Federation criteria. Results A total of 3,561 participants from Survey 2010 were included in the data analysis. Women had a significantly higher prevalence of MetSyn than men. Comparison between the two surveys shows that age-standardized prevalence of MetSyn increased fourfold (from 5.4% in 2002 to 21.3% in 2010) in those ≧ 20 years. Among the MetSyn components, prevalence of hyperglycaemia has increased most (from 9.1% to 53.1%). The age-standardized prevalence of central obesity, hypertension, hypertriglyceridaemia and low HDL-cholesterol increased from 13.5% to 25.4%, from 23.6% to 40.8%, from 12.1% to 17.4% and from 32.1% to 71.1%, respectively. Differences between rural and urban residents in the prevalence in MetSyn and its components narrowed in 2010. Conclusions Cardiovascular risk escalated dramatically in this population between 2002 and 2010. The escalation may relate to the rapid economic development, which led to accelerating changes in nutrition, lifestyle, and socio-economic status. Our findings suggest that health transition in rapidly developing second- and third-world countries may be much faster than what has been observed in Western countries., published_or_final_version

This paper introduces the wavelet transform, and based on which brings forward a new computer doable method. When an image is processed by multi-level 2-dimension dispersed wavelet transform, we can get two data information: the low frequency and the high frequency, after that, we add some random data to the high frequency, and then reconstruct the image. When testing, we use the same wavelet decomposition method to detect the correlation between the high frequency and the random data. This method can be used to avoiding the image forgery.