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With the development of new materials and technology, high entropy alloy (HEA) nitride films have attracted much attention of researchers due to their excellent optical properties and mechanical properties. Herein, a novel SS/NbMoTaWN (HEAN)/NbMoTaWON (HEAON)/SiO2 coatings are prepared, which shows a high spectral selectivity of α/e = 0.944/0.12. The preparation and optimization of the coating are studied by combining experiments with ellipsometric program and CODE software. High temperature thermal stability test is performed in depth, which proves that the coating could bear 400 °C in air for 2 h, and 600 °C for 2 h in vacuum. Long-term thermal stability researches indicate that the SSACs still keep good optical properties (α = 0.902, e = 0.106) even after annealing at 600 °C for 100 h. The failure mechanism is analyzed by XRD and Raman spectra. In addition, neutral salt spray test is performed to investigate the anti-corrosion ability, which indicates the coating has a good optical performance after soaking in 3.5 wt% NaCl solution for 30 days. Obviously, this work provides a new strategy to construct solar absorber coatings based on NbMoTaW high entropy alloy.

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.

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.

In order to improve our knowledge of the mechanical effect of the roots of mixed-plantings on soil reinforcement and slope protection, the influence of roots of a mixed-planting with four herb species (Medicago sativa L., Elymus nutans Griseb., Puccinellia distanx (L.), and Poa pratensis L.) and one shrub species (Caragana korshinskii Kom.) were investigated on the shear strength characteristics of saline loess soil. The root distribution characteristics were assessed via a survey when the plants grew for one year. The effects of the root biomass density, the root mass ratio (RMR) of the fine roots to the coarse roots, the moisture content, and the salt content on the shear strength index of the rooted soil were analyzed via a triaxial compression test, and the mechanism of these effects was discussed. The results indicate that the biomass density decreased linearly with increasing depth. The RMR initially decreased with depth and then increased, exhibiting in a quadratic relationship. The cohesion of the rooted soil increased linearly as the biomass density increased. The cohesion of the rooted soil initially increased with increasing RMR and salt content, and then it decreased. The turning point of the cohesion occurred when the RMR was 0.6 and the salt content was 1.18%. The internal friction angle of the rooted soil initially increased with biomass density and then decreased, and the turning point of the internal friction angle occurred when the biomass density was 0.015 g/cm3. The relationships between the internal friction angle of the rooted soil and the RMR and salt content were exponential incremental and linear subtractive relationship, respectively. Both the cohesion and the internal friction angle of the rooted soil linearly decreased with increasing moisture content.

Flowering time, a key transition point from vegetative to reproductive growth, is regulated by an intrinsic complex of endogenous and exogenous signals including nutrient status. For hundreds of years, nitrogen has been well known to modulate flowering time, but the molecular genetic basis on how plants adapt to ever-changing nitrogen availability remains not fully explored. Here we explore how Arabidopsis natural variation in flowering time responds to nitrate fluctuation. Upon nitrate availability change, we detect accession- and photoperiod-specific flowering responses, which also feature a accession-specific dependency on growth traits. The flowering time variation correlates well with the expression of floral integrators, SOC1 and FT, in an accession-specific manner. We find that gene expression variation of key hub genes in the photoperiod-circadian-clock (GI), aging (SPLs) and autonomous (FLC) pathways associates with the expression change of these integrators, hence flowering time variation. Our results thus shed light on the molecular genetic mechanisms on regulation of accession- and photoperiod-specific flowering time variation in response to nitrate availability.

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.

Genome-wide identification of WD40-like genes reveals a duplication of COP1-like genes, one of the key players involved in regulation of flowering time and photomorphogenesis, with strong functional diversification in Rosaceae. WD40 proteins play crucial roles in a broad spectrum of developmental and physiological processes. Here, we conducted a systematic characterization of this family of genes in Rosa chinensis 'Old Blush' (OB), a founder genotype for modern rose domestication. We identified 187 rose WD40 genes and classified them into 5 clusters and 15 subfamilies with 11 of RcWD40s presumably generated via tandem duplication. We found RcWD40 genes were expressed differentially following stages of vegetative and reproductive development. We detected a duplication of CONSTITUTIVE PHOTOMORPHOGENIC1-like genes in rose (RcCOP1 and RcCOP1L) and other Rosaceae plants. Featuring a distinct expression pattern and a different profile of cis-regulatory-elements in the transcriptional regulatory regions, RcCOP1 seemed being evolutionarily conserved while RcCOP1L did not dimerize with RcHY5 and RcSPA4. Our data thus reveals a functional diversification of COP1-like genes in Rosacaeae plants, and provides a valuable resource to explore the potential function and evolution of WD40-like genes in Rosaceae plants.

Heavy metals are widely distributed contaminants in natural environments and their potential threats to human health have attracted worldwide concerns due to the food chain. Therefore, great efforts have been made to reduce them to a safe level in soil. Compared with the traditional methods, the method using plants to remove them has been accepted as a feasible and efficient way. Herein, the geochemical behavior of heavy metals and the restoration methods with phytoremediation were reviewed. In addition, issues on heavy metal speciation as well as its influencing factors, phytoremediation mechanism, phytoremediation effect and vegetation selection principle used for phytoremediation were discussed.

Moisture and salt content of soil are the two predominant factors influencing its shear strength. This study aims to investigate the effects of these two factors on shear strength behavior of loess in the Xining Basin of Northeast Qinghai-Tibet Plateau, where such geological hazards as soil erosion, landslides and debris flows are widespread due to the highly erodible loess. Salinized loess soil collected from the test site was desalinized through saltleaching in the laboratory. The desalinized and ovendried loess samples were also artificially moisturized and salinized in order to examine how soil salinity affects its shear strength at different moisture levels. Soil samples prepared in different ways (moisturizing, salt-leaching, and salinized) were measured to determine soil cohesion and internal friction angle. The results show that salt-leaching up to 18 rounds almost completely removed the salt content and considerably changed the physical components of loess, but the soil type remained unchanged. As salt content increases from 0.00% to 12.00%, both the cohesion and internal friction angle exhibit an initial decrease and then increase with salt content. As moisture content is 12.00%, the salt content threshold value for both cohesion and internal friction angle is identified as 3.00%. As the moisture content rises to 16.0% and 20.00%, the salt content threshold value for cohesion is still 6.00%, but 3.00% for internal friction angle. At these thresholds soil shear strength is the lowest, below which it is inversely related to soil salinity. Beyond the thresholds, however, the relationship is positive. Dissimilar to salinity, soil moisture content exerts an adverse effect on shear strength of loess. The findings of this study can provide a valuable guidance on stabilizing the engineering properties of salinized loess to prevent slope failures during heavy rainfall events.

This study aims to assess the hydrological effects of four herbs and four shrubs planted in a selfestablished test area in Xining Basin of northeastern Qinghai-Tibet Plateau, China. The Rainfall-Intercepting Capability (RIC) of the herbs and shrubs was evaluated in rainfall interception experiment at the end of the third, fourth and fifth month of the growth period in 2007. The leaf transpiration rate and the effects of roots on promoting soil moisture evaporation in these plants were also assessed in transpiration experiment and root-soil composite system evaporation experiment in the five month’s growth period. It is found that the RIC of the four studied herbs follows the order of E. repens, E. dahuricus, A. trachycaulum and L. secalinus; the RIC of the four shrubs follows the order of A. canescens, Z. xanthoxylon, C. korshinskii and N. tangutorum. The RIC of all the herbs is related linearly to their mean height and canopy area (R2 ≥ 0.9160). The RIC of all the shrubs bears a logarithmic relationship with their mean height (R2 ≥ 0.9164), but a linear one with their canopy area (R2 ≥ 0.9356). Moreover, different species show different transpiration rates. Of the four herbs, E. repens has the highest transpiration rate of 1.07 mg/(m2·s), and of the four shrubs, A. canescens has the highest transpiration rate (0.74 mg/(m2·s)). The roots of all the herbs and shrubs can promote soil moisture evaporation. Of the four herbs, the evaporation rate of E. repens root-soil composite system is the highest (2.14%), and of the four shrubs, the root-soil composite system of A. canescens has the highest evaporation rate (1.41%). The evaporation rate of the root-soil composite system of E. dahuricus and Z. xanthoxylon bears a second-power linear relationship with evaporation time (R2 ≥ 0.9924). The moisture content of all the eight root-soil composite systems decreases exponentially with evaporation time (R2 ≥ 0.8434). The evaporation rate and moisture content of all the plants’ root-soil composite systems increases logarithmically (R2 ≥ 0.9606) and linearly (R2 ≥ 0.9777) with root volume density. The findings of this study indicate that among the four herbs and four shrubs, E. repens and A. canescens possess the most effective hydrological effects in reducing the soil erosion and shallow landslide in this region.

The newly increasing development of abruptly high entropy alloy nitride (HEAN), especially the refractory HEAN, manifests excellent mechanical, corrosion resistance , and optical properties, which exhibits a wide application prospect in the field of coatings. Herein, we develop a high entropy nitride NbMoTaWN-based solar selective absorber coatings (SSACs), providing a potential to strengthen structural and optical advance through component selection and structure design. The coating exhibits a high solar absorptance (α) of 0.936 and a low thermal emittance ( e ) of 0.126 at 82 °C. Investigation on structural and optical robustness demonstrates that the NbMoTaW HEAN-based SSAC could endure heat treatment at 500 °C for 10 h in vacuum environment. In addition, through the evolution of XRD and Raman spectra after annealing, the failure mechanism of coatings annealed in vacuum at 500 °C for 10 h and 400 °C in air for 5 h are obtained. Obviously, the advantages such as low-cost preparation, easily scalable production, convenient technology process, and repeatability in this work promise potentially valuable applications for photothermal conversion techniques.

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.

A novel TiC-TiN/Al2O3 tandem solar selective absorbing coating was successfully deposited on Si (1 0 0) and stainless steel (SS) substrates by reactive RF magnetron sputtering deposition. The spectral characteristics, microstructure, thermal stability and solar-thermal conversion efficiency of the coating before and after a long annealing in vacuum were investigated systematically. The optical constants of the coating are measured by an Ultraviolet–visible-near-infrared (UV/Vis/NIR) spectrometer, and the chemical composition analysis, structure information and surface morphology are investigated using XRD, XPS and FESEM. An excellent absorptance (α = 0.92) and a low emittance (e = 0.11) at 82 °C are obtained by the as-prepared coatings. After annealed at 500 °C for 100 h in vacuum, there is no significant change in micromorphology and optical properties of the coating, which produces a good solar-thermal conversion efficiency. These results indicate that it can be applied as a potential coating material to a high temperature concentrated solar power (CSP) system.

Bio-synthesis of nano-metal oxide particles is gaining lot of significance and recommended as promising substitute not only physical methods but also chemical methods. Here in, we demonstrate the nano-zinc oxide (nano-ZnO) particles were successfully prepared by an eco-friendly process using plant Barleria gibsoni (B. gibsoni) aqueous leaf extract. The water leaf extract of B. gibsoni responsible for not only reducing source but also protective agent. The prepared nano-ZnO particles were studied by UV–Vis diffuse reflectance (UV-DRS), Photoluminescence (PL), Fourier transform (FT-IR) infrared spectroscopy, X-ray diffraction spectroscopy (X-RD), transmission electron microscopy (TEM), thermal stability was studied by thermogravimetric and differential thermal (TG-DTA) analysis and particle size by zeta sizer, dynamic light scattering (DLS). UV-DRS spectrum of nano-ZnO particles showed below at wave length 400 nm. FT-IR spectra showed that plant metabolites like polyphenols, flavonoids and amino acids etc., are act as reducing and protective agent. X-RD studies revealed the formed nano-ZnO particles have hexagonal (wurtzite) structure. TEM analysis confirmed the range of nanoparticles between 30 and 80 nm, which is supported by DLS analysis. The antibacterial property of synthesized nano-ZnO particles was tested with bacterial pathogens showed good results. The developed nano-ZnO gel act as an efficient and superior another tropical antimicrobial formulations for healing of burn infections. Moreover, the formulated nano-ZnO gel exhibited a remarkable wound healing potential in rats.

Tectonic uplift is the primary control upon the low relief yet moderately undulating plateau landscapes that make up much of the source zone of the Yellow River. Steep ravines and gullies are restricted to mountain ranges at the northern and southern margins. This contrasts starkly with the deeply dissected landscapes at the eastern margin of the Qinghai–Tibet Plateau. Although the high elevation induces low mean annual temperatures, diurnal temperature ranges are high. Precipitation is sparse but concentrated, and gales are frequent. Hillslope processes such as landslides, debris flows, solifluction and soil erosion are extensively developed in the region. This chapter presents an overview of hillslope stability in the Yellow River Source Zone. First, the landscapes and topography of the Yellow River Source Zone are introduced. Landslide, debris flow, soil erosion (aeolian and rill/gully) and freeze-thaw processes are shown to be key drivers of patterns and rates of grassland degradation. Human activities and climate change are key agents of landscape change. The influence of vegetation management upon hillslope stability and in reducing geological disasters is demonstrated. Vegetation plantation and increased vegetation cover enhance the mechanical and hydrologic effects of hillslope protection, increasing soil shear strength and interception of rainfall.