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In this study, a facile method to fabricate Janus microbeads based on photonic crystals and upconversion nanoparticles is designed. The Janus microbeads can be reversed under magnetic response and generate upconversion fluorescence under near-infrared light. Three kinds of core-shell upconversion nanoparticles (UCNPs) are prepared by the solvothermal method and are mixed with Fe3O4 nanoparticles and different sizes of colloidal spheres. The Janus microbeads are assembled according to the hydrophilic property of the mixture and the hydrophobic property of substrates. The upper parts of the Janus microbeads are photonic crystals assembled with colloidal spheres, and the other parts are Fe3O4. Meanwhile, UCNPs are distributed inside the Janus microbeads. Furthermore, the Janus microbeads are prepared into different lattice patterns using special templates. In the lattice patterns, the structural colors of Janus microbeads can be displayed and disappeared by magnetic field inversion, and under external NIR irradiation, Janus microbeads can generate upconversion fluorescence to achieve multiple color display. The Janus microbeads are also applied to both sides of the bank card, and various reading information methods are designed according to different response modes, which have important applications in pattern display, response materials, and anti-counterfeiting.

Basing on the unique advantages of uniform and rapid volumetric heating of microwave irradiation, microwave hydrothermal method has been used to fabricate Br/Bi2WO6 for streamlining the preparation procedure and enhancing the photocatalytic activity. The results indicated that Br was successfully introduced into the lattice of Bi2WO6, which improved the absorption ability of visible light. Moreover, Br/Bi2WO6 exhibited smaller size and the enhanced separation efficiency of photogenerated carriers as compared with Bi2WO6. Br/Bi2WO6 exhibited superior reusability and photocatalytic activity of Rhodamine B (RhB) and tetracycline (TC). Furthermore, the enhanced photocatalytic activity of Br/Bi2WO6 was mainly ascribed to the increased specific surface area, wide UV-vis light absorption range, and high separation efficiency of photogenerated charge carriers originating from Br doping and microwave heating.

Wind erosion is the main form of soil erosion in arid and semi-arid areas. It leads to soil loss and land degradation, which aggravates ecosystem vulnerability and threatens regional sustainable development. The assessment of wind erosion and the study of its driving factors can reduce soil wind erosion and provide decision-making assistance to solve environmental problems. Southern Africa is affected by severe soil erosion, which has brought a series of development problems, such as food crises and poverty. This study used meteorological and remote sensing data, and the revised wind erosion equation model to explore the temporal and spatial dynamics of soil erosion in southern Africa from 1991 to 2015. The impact of climate dynamics on soil wind erosion was also analyzed. The results showed that wind erosion fluctuated during the study period, and it first showed a downward trend and then stabilized at a relatively low level after 2010. Soil wind erosion across 66.65% of the study area significantly decreased (p < 0.05) and near-surface wind speed was the most important factor. The change in wind speed had a positive impact on soil wind erosion across 68.18% of the area. Temperature and precipitation were significantly related to soil wind erosion over 18.96% and 24.63% of the area, respectively. Both can also indirectly affect soil wind erosion through their effects on vegetation cover. This study will help decision-makers to evaluate areas that are at high-risk from soil erosion in southern Africa and enable them to effectively protect fragile ecosystems.

Despite many successful realizations of laser operations in various micro/nanostructured lead halide perovskites (LHPs), the electron–hole plasma (EHP) lasing dynamics has only rarely been reported...

Understanding the relationships among multiple ecosystem services could improve the landscape capacity to provide benefits to human society. However, the underlying mechanisms shaping ecosystem services relationships are still unclear although some studies have been conducted to explore how natural and socioeconomic factors influence the relationships among ecosystem services. In this study, the karst landscape in southwestern China, a vulnerable system with intensive human activities, was focused on, aiming to explore relationships between ecosystem services and associated social and ecological factors. The results showed that the distribution of eight individual ecosystem services were spatially heterogeneous and clustered based on the characteristics of the karst landscape. The relationships between provisioning services and regulating services, such as grain production and net primary productivity, as well as water yield and soil retention, were quite different between high karst coverage regions and low karst coverage regions. Among five ecosystem service bundles identified, ecosystem services in the urban development bundle were mainly determined by socioeconomic factors, while in the other four bundles of multifunction, grain production, habitat conservation, and carbon sequestration, ecosystem services were dominated by ecological factors. However, socioeconomic factors (i.e. population density and night-time light intensity) appeared to explain the overall ecosystem service delivery more than karst terrain. This study provided insights for sustainable ecosystem management in a vulnerable karst region through exploring social-ecological factors of the relationships among ecosystem services.

Wind erosion is the main cause of land degradation and desertification in drylands. Severe wind erosion affects regional ecological security and endangers the health of people. The Horqin Sandy Land is one of the largest sandy lands in China. It suffers from severe wind erosion and is one of the main sources of sand storms in the Beijing–Tianjin–Hebei region. The spatiotemporal dynamics of wind erosion and its driving factors were explored in this study by using the Revised Wind Erosion Equation to evaluate wind erosion in the Horqin Sandy Land from 2001 to 2016. The year was divided into four phases according to the distribution of the wind erosion modulus, and the differences between the annual scale and the seasonal scale wind erosion characteristics were analyzed. The annual average wind erosion across the Horqin Sandy Land from 2001 to 2016 was 5.50 t/hm2, and wind erosion showed an obvious downward trend at a speed of 0.82 t/hm2/a. High intensity wind erosion mainly occured from March to May, which accounted for 67.95% of the total erosion per year. Although the wind erosion in each phase of the year showed downward trends, the rate in the spring was substantially higher than that in other phases. The main reasons for the decrease in wind erosion were the reduction in wind speed and the restoration of vegetation, with the contribution of −55.78% and −42.68%, respectively. Vegetation coverage dominated the decline in wind erosion in a number of areas, but areas with severe wind erosion were dominated by wind speed. Furthermore, wind speed in the spring was the dominant factor driving the decline in wind erosion across the Horqin Sandy Land. Major wind erosion control programs should be aimed to restore vegetation in severely desertified areas of the Horqin Sandy Land.

The effect of Fe3O4 content and microwave reaction time on the properties of Fe3O4/ZnO magnetic nanoparticles (ZnO MNPs) was investigated. The corresponding structural properties of the ZnO MNPs were demonstrated by a series of characterization techniques including Brunauer–Emmett–Teller (BET), X–ray diffraction (XRD), field emission scanning electron microscopy (FE–SEM), high resolution transmission electron microscopic (HR–TEM), X-ray photoelectron spectroscopy (XPS), UV–Vis diffuse reflectance (UV–vis DRS), Fourier transformed infra-red (FT–IR) spectroscopy and vibrating sample magnetometer (VSM). Photocatalytic activity of the ZnO MNPs was evaluated by choosing 4–Nitrophenol (4–NP) as the target pollutant. The Characterization and experimental results indicated that the ZnO MNPs containing 20% Fe3O4 exhibited the largest specific surface area, pore volume and average pore diameter along with the strongest UV‒light absorption capacity. Moreover, diameters of the spherical ZnO MNPs decreased with the increase of Fe3O4 contents. Furthermore, saturation magnetization of the ZnO MNPs increased with increasing Fe3O4 contents, and the ZnO MNPS with 20% and 30% Fe3O4 contents exhibited good superpara–magnetic behavior and coercivity, respectively. The best degradation of 4–NP was exhibited in ZnO MNPS with 30% Fe3O4 content. On the other hand, the best photocatalytic activity was exhibited by ZnO MNPs prepared by 30 min microwave reaction time. The morphology was independent of microwave reaction time, while agglomerates of the ZnO MNPs were observed with increasing microwave reaction time up to 60 min. The study comprehensively discovered that the ZnO MNPs prepared with 20% Fe3O4 content and 30 min microwave reaction time exhibited enhanced degradation of 4–NP up to 99% within 120 min. As a conclusion, Fe3O4 content and microwave reaction time played an important role in the structural fabrication, photodegradation properties and reusability of ZnO MNPs. The current study could be deemed of great potential for the preparation and applications of ZnO MNPs in environmental remediation.

This paper aimed to explore the effects of Spartina alterniflora invasion on the contents and structure of soil dissolved organic matter (DOM, including dissolved organic carbon (DOC), dissolved organic nitrogen (DON), dissolved organic phosphorus (DOP), and dissolved organic sulphur (DOS)) in the Yanghe estuary, by the aid of ultraviolet-visible spectrum, three-dimensional fluorescence spectrum, and Fourier transform infrared spectroscopy. Soil samples were collected at 0–60 cm depths in different invasion years (0, 1, 5, and 8). The results showed that the DOC increased gradually with the increase of invasion time of S.alterniflora; whereas the contents of DON and DOP decreased. In the vertical section, all the DOM showed a decreasing trend with the increase of the soil profile except the DOC content in SAF-5 and SAF-8 plots (The SAF-5 and SAF-8 represent for the invasion time of 5 years and 8 years). The spectral analysis showed that the macromolecules of DOM increased after the invasion. The molecular weight and number of molecules of DOM changed after invasion. The changes were mainly concentrated in refractory macromolecules. S.alterniflora had a significant effect on the number of structural units and functional groups of soil DOM. The intensity of functional group peaks became stronger, and aromatic, aliphatic, and carbohydrate substances increased. In addition, the quantity and quality of soil DOM input by S.alternifolia strongly affect the complexity of DOM chemical structure. With the increase of invasion time, the degree of humification increases and the structure of DOM tends to be more complex. The findings of this study indicate that the invasion of S.alternifolia would enhance DOM owing to greater amount of biomass.

Ecosystem services are essential for the well-being of humans, and the measurement of ecosystem service provision and consumption is an effective approach for estimating regional sustainability. In this work, an ecosystem service footprint (ESF) model was presented to calculate ecosystem service consumption in China from 2000 to 2014. Seven service footprints were estimated in this model, namely, food provision, raw material provision, freshwater provision, energy (hydropower) provision, air purification, climate regulation, and tourism and leisure. Results showed that from 2000 to 2014, the average annual ESF was 2.78 ha per capita, and the provisioning, regulation, and cultural service footprints were 1.56, 1.20, and 0.02 ha per capita, respectively. ESF exhibited an increasing trend during this period. National ecosystem services presented a slight upward deficit, with the eastern region having the highest deficit and a slight surplus in the western region. Each provincial-level administrative region can be classified into one of four categories based on two dimensions, gross domestic product (GDP) and their ecosystem service surplus (ESS) or deficit (ESD) situation. High GDP values and ESD situation provinces are mainly located in coastal areas, whereas low-GDP and ESS situation provinces are located in the northwest and southwest regions. The model is expected to provide scientific basis and direction for optimizing environmental management.

Long-range ordered macroporous inverse opal hydrogel particles with methanephosphonic acid (MPA) imprinted sites have been designed and prepared through a sacrificial template method for the in situ molecule recognition process. The hydrogel particles showed well specific selectivity to MPA and obvious reflection peak shift which can be recognized by naked eyes. Because of the hydrogen bond interaction between MPA and polymethacrylic acid (PMAA), the macropores of the hydrogel matrix gradually swell during the recognition process. The prepared MPA imprinted crystal colloidal arrays hydrogel particles can be used as the colorimetric sensors for the detection of the existence of the MPA, achieving a 120 nm large red shift of its reflection peak leading to the interaction between the MPA and the imprinting sites. In addition, the size of the hydrogel particles is systematically studied, which inspires us to obtain the appropriate range of MPA sensor by controlling the size of the hydrogel particles to fit the different standard. In combination with food safety, hydrogen affinity molecularly imprinted polymer (MIP) inverse opal suspension arrays sensors here are of potential application for the building of the pesticide detection system.

In order to endow alkaline Ca-bentonite (ACB) with magnetic separation ability, simultaneously obtain better magnetic stability and stronger removal capacity of heavy metal cations; magnetic alkaline Ca-bentonite/carboxymethylcellulose-chitosan film (MACB/C-C) was prepared by organic modification of magnetic alkaline Ca-bentonite (MACB) using non-toxic carboxymethylcellulose and chitosan. Textural characterization results revealed that magnetic Fe3O4 nanoparticles were successfully immobilized on ACB and modified with C-C. The functionalized layer of C-C concurrently enhanced the stability of Fe3O4 and removal performances of heavy metal cations. Adsorption results indicated that MACB/C-C exhibited thorough separation from aqueous solution and greater uptake ability for Pb(II) and Cd(II) (483 mg·g-1 and 123 mg·g-1) than the nascent MACB (335 mg·g-1 and 76 mg·g-1), respectively, at pH 5 and 25 °C temperature. The adsorption of Pb(II) and Cd(II) on MACB/C-C mainly occurred via surface precipitation and complexation when pH > 2. MACB/C-C could be efficiently recycled with marginal decrease in adsorption capacity. The current approach credited to the convenient operation, simplified synthesis, and high efficiency of MACB/C-C could be deemed as a promising alternative for the removal of heavy metal cations from wastewater.

Patterned colloidal crystals with stimuli-responsive materials provide sensitive and versatile means for investigating the varying ambiance of heat, light, electricity, magnetism, and stress. However, it remains a challenge to integrate stimuli-responsive materials with colloidal crystals by a simple and efficient method, thus restricting them from being used in general applications. Inspired from chameleons, we present a facile yet high-quality approach for the fabrication of the assembly of colloidal nanoparticles based on the hydrophilic-modified thermosensitive films. Various kinds of integral thermosensitive structural colored (TSSC) films are simply prepared in a high-quality screen on a large scale, with low cost, angle independence, and excellent flexibility. Simply turning on the near-infrared (NIR) laser brings heat to the irradiated region to increase the temperature. Integration of the multi-colored photonic bandgap (PBG) of the thermal-sensitive colloidal crystal and flexible anti-counterfeit labels into the NIR light exciting screens can change the intensity of PBG obviously. This advanced technology not only provides an efficient strategy for the preparation of colloidal crystal but also demonstrates a highly thermosensitive structural colored screen that has great prospect for information storage, anticounterfeiting, and real-time display materials.

In this study, we developed a new kind of dual-mode multicolored photonic crystals (PCs), which could be used as a new type of dye, and achieved multicolored patterns. This kind of PCs can exhibit not only distinct structural colors due to Bragg's law of diffraction but also non-structural colors due to fluorescence. We used ultraviolet (UV)-responsive colloidal spheres synthesized by polymerization of semi-continuous emulsions to assemble the PCs. In this synthesis, the fluorescent precursors with carbamate groups were locally restricted to the shell of prepared spheres. UV irradiation can induce photo-decomposition of the carbamate groups in the fluorescent precursors, generating amino groups in the process. This process allowed the assembled PCs to exhibit fluorescence through treatment with fluorescamine. We prepared two-dimensional (2D) multicolored photonic patterns of different sizes, with both reflection and fluorescence modes. These patterns were prepared either by vertical deposition under selective UV irradiation, or by spray coating. In addition, we fabricated three-dimensional (3D) multicolored photonic patterns using 3D templates, as well as through spray coating. The results expand the concept of responsive PCs, and offer potential applications for multicolored photonic crystal patterns (PC patterns) in the field of optical storage, color displays, and anti-counterfeiting.

A series of Zn2GeO4:Tb3+ nanophosphors have been prepared by the high temperature solid state method. The XRD patterns of samples are basically consistent with Zn2GeO4 standard card and the influence of Tb3+ ion on the peak shift is discussed detailedly. The SEM results show that the average sizes of all nanophosphors, whether undoped or doped, are about 50 nm except that some particles in Zn2GeO4 nanophosphor doped with 0.7 mol% terbium take on the cubic structure and the maximum size are about 130 nm. Under 265 nm excitation, there exists a broad blue emission belonging to Zn2GeO4 host. Moreover, the intense photoluminescence peaks at 490, 550 nm and weak peaks at 585, 622 nm of Tb3+ ions are obtained, and optimum Tb3+ doping concentration is 0.7 mol%. The decay curves of host emissions with the varied Tb3+ concentrations are measured, and the mechanisms of photoluminescence and energy transfer from Zn2GeO4 host to Tb3+ ions are analyzed systematically.

Nitrophenols in wastewater have posed a serious threat to ecosystem and human health, hence it is very important to remove them from wastewater using an environmental-friendly and effective method. In this study, Fe3O4@SiO2@ZnO magnetic nanoparticles (ZnO MNPs) were synthesized via a moderate and rapid route using microwave irradiation and diethylene glycol (DEG) as solvent. The facile synthesis conditions of ZnO nanoparticles coating on Fe3O4@SiO2 were confirmed owing to lower reaction temperature (160 °C) and quick reaction time (15 min microwave irradiation). In addition, the synthesized ZnO MNPs demonstrated the comparable or even better photocatalytic activity for 4-nitrophenol (4-NP) as compared with TiO2 with respect to small catalyst dosage, quick degradation rate and broad pH range. Moreover, ZnO MNPs exhibited good stability and reusability after eight times successive degradation experiments of 4-NP. The mechanism of the enhanced photocatalytic activity of ZnO MNPs was mainly related to the stronger adsorption ability for 4-NP, the improved light absorption ability and the retarding recombination of hole–electron pairs. In summary, ZnO MNPs is a promising candidate for 4-NP photocatalytic degradation from wastewater.

We consider the synchronization transmission problem of spiral wave and turbulence within the uncertain switching network. Through constructing reasonably the Lyapunov function of the network, the uncertain switching network not only can transfer synchronously the spiral wave and turbulence originated from the synchronization target, but also the chattering near the synchronization target can be eliminated, which indicates that the synchronization performance of the network is more stable. At the same time, the adaptive laws of the uncertain parameters are designed and the uncertain parameters in the switching network nodes are replaced effectively.

Botryoidal dolostone (BD) developed extensively within the Neoproterozoic Upper Sinian Dengying Formation in the Hanyuan region, which is an important gas reservoir. Based on literature review, a study of their outcrop characteristics, petrology, microfabric, degree of order, and genesis reveal that BD mainly comprises botryoidal lumps (BL) originated from depositional-penecontemporaneous seawater and botryoidal and ctenoid cements or fillings. BL occurred in parallel beds during the depositional-syngenetic stage, including core and coating. The core consists of grapestone and thrombolite, which is dominated by muddy and microcrystalline high-magnesium calcite (HMC) resulting from marine deposition and micro-organism capturing and binding effects. The coating, classified as either thin or thick, is mainly isopachous fibrous aragonite (IFA) that formed during the depositional-syngenetic stage. Thin coatings formed in the turbulent sea bottom, while thicker ones formed in a relatively quiet sea bottom. Botryoidal and ctenoid cements and fillings compose IFA and HMC. IFA that includes marine phreatic zone deposition from the syngenetic-penecontemporaneous stage mainly occurs in the spaces between grains of BL and intraclast or on the top of them. The HMC that is the product from meteoric leaching in the penecontemporaneous stage and marine deposition occurs in the dissolved pores and fractures. During the process when BL and the botryoidal, ctenoid cements, or fillings formed, either abiogenetic or microbiogenic aragonite and HMC were mimetically dolomitized and preserved the primary texture and structure. BD was also reworked by the meteoric leaching in the penecontemporaneous and supergenous stages.

To reveal the characteristics of tetracycline (TC) photocatalytic degradation under Cu(II) coexistence, effects of Cu(II) on TC photocatalytic degradation by ZnO nanoparticles (ZnO NPs) as a function of pH, humic acid (HA), and initial Cu(II) concentration were investigated. Interaction of TC with Cu(II) in the treatment process was analyzed by circular dichroism (CD) spectroscopy, while TC degradation pathway was investigated by high-performance liquid chromatography-mass spectrometry. Sixty-five percent and ninety-one percent TC degradation within 60 min in the absence and presence of Cu(II), respectively, was reported. Both adsorption and photocatalytic degradation of TC under Cu(II) coexistence increased with increasing pH from 3 to 6, while decreased with further increase in pH. HA inhibited the degradation of TC by ZnO NPs both in the presence as well absence of Cu(II), while TC degradation decreased from 91 to 73% and from 73 to 37% in the presence and absence of Cu(II), respectively. TC degradation by ZnO NPs first increased then decreased with increasing Cu(II). Maximum TC degradation (about 94%) was obtained in the optimum concentration range of Cu(II) (0.05–0.15 mmol/L). In addition, there was a lag effect between TC adsorption and degradation on ZnO NPs. TC degradation was improved via Cu(II)–TC surface complexation and followed N-demethylation and hydroxylation routes. This study could be of potential importance in extrapolating the transformation of TC or other antibiotics under the coexistence of heavy metals in water.

We developed a type of dye-doped cholesteric liquid crystal, which were used for fluorescence enhancement and dual-mode multicolor patterns. We added dye molecules (BBOT, coumarin 6 (C6) and rhodamine B (RhB)) to liquid crystals, and cholesteric liquid crystals (CLC) exhibited selective reflection characteristics. When the reflection wavelength overlaps with the peak of the fluorescent dye, the luminescence intensity of the dye molecules could be adjusted. We used two methods to adjust the reflection wavelength of the cholesteric liquid crystals by changing the content of chiral additives and the isomerization degree of azo molecules. We used the screen printing and stencil printing methods to combine liquid crystal particles containing different fluorescent colors to prepare multicolor patterns. Moreover, the photoisomerization characteristics of the azo molecules were also used to achieve brilliant firework-like images upon exposure to ultraviolet and visible light. In addition, we also realized a face-changing stunt with facial makeup during a performance in the Sichuan Opera, a traditional Chinese folk art. We made use of the difference between reflection color and luminescence intensity upon light irradiation to present orange, green, blue and dark-blue facial effects.

Raw bentonite (RB) was chemically modified by citric acid (CA) to obtain a low-cost and environment-friendly citric acid incorporated bentonite (CAB) adsorbent, which was applied for the adsorptive removal of Congo Red (CR). The effect of adsorbent dosage, contact time, ionic strength, surfactant, and pH on adsorption was investigated. Adsorption equilibrium data fitted well with Langmuir model while the Langmuir adsorption capacity of CR on CAB reached up to 384 mg·g−1. Furthermore, CR adsorption on CAB followed pseudo-second kinetic model while intra-particle diffusion was not the only rate-limiting step as determined from intra-particle diffusion model investigation. RB and CAB were characterized by XRD, FT-IR, and BET techniques. A proposed mechanism for the adsorption of CR over CAB suggested the chemical adsorption phenomenon is mainly controlled by chelation, hydrogen bonding, and fixing.

Wind erosion is one of the major environmental problems in drylands. Identifying the dominant natural factors of wind erosion and using targeted treatment measures are the key steps in wind erosion control. Using Horqin Left Back Banner in China as a case study, we applied the revised wind erosion equation to simulate the spatial distribution of wind erosion in the semi-arid sandy area. Contribution assessment and constraint line analysis were used to investigate the contributions of driving forces to wind erosion changes. The results showed that the wind erosion in the whole area was reduced by 0.35 t/hm2·a from 2005 to 2016. The wind factor and vegetation coverage factor had dominant contributions to the wind erosion modulus and accounted for the erosion in 49.87% and 50.13% of the total area, respectively. In addition, the average wind speed exceeding the threshold and the number of occurrences exhibited significant correlations with the wind erosion severity. Meanwhile, the mitigation effects of vegetation coverage on wind erosion decreased with the increase in wind speed. The temporal mismatch between the wind speed and vegetation coverage was the main reason for the frequent severe wind erosion in spring. Reducing the spring wind speed through adding windbreaks would be an effective method for decreasing wind erosion in semi-arid areas.

To obtain an effective, cheap and recyclable adsorbent for refractory pollutants removal, carboxymethyl cellulose (CMC) and chitosan (CS) modified magnetic Fe3O4/alkaline Ca-bentonite (MACB-CC) was successfully fabricated by modifying magnetic Fe3O4/alkaline Ca-bentonite (MACB) with both CMC and CS via the Schiff base reaction. The designed adsorbent exhibited stable magnetic separation ability and excellent adsorption for doxycycline (DC) (96%) as compared to the pristine MACB (84%). DC adsorption efficiency increased with increasing time from 0 to 2 h for MACB and MACB-CC and then reached to equilibrium. The optimum pH value/range for DC adsorption were achieved at pH 7.0 and 4.0 ∼ 8.0 for MACB and MACB-CC respectively. DC adsorption was boosted by the presence of humic acid in low concentration (20 ∼ 40 mg L−1 and 0 ∼ 40 mg L−1 for MACB and MACB-CC respectively). The mechanism of DC adsorption on MACB-CC mainly included complexation, electrostatic attraction and deposition. The adsorption data of DC both on MACB and MACB-CC fitted well with the pseudo-second-order kinetic model and Langmuir adsorption isotherm model. MACB-CC achieved 1.2 times higher uptake for DC (643 mg g−1) than that of MACB. The enhanced adsorption of DC could be ascribed to the synergistic organic modification by CMC and CS. In addition, MACB-CC exhibited good magnetic separation ability and magnetic stability during the recycling process, and hence could be deemed as a promising alternative for DC adsorption from wastewater on industrial level.

Land use and cover change is an important concept in the study of ecosystem services, especially in ecologically fragile areas. This study generated three scenarios, namely historical trend (HT), national planning (NP), and windbreak and sand fixation (WS), by using the CLUMondo model and Bayesian belief network (BBN) to explore land use with diverse demands. The CLUMondo model was utilized to simulate the land use probability surface of Horqin Sandy Land in 2025 under different scenarios. A BBN was constructed to investigate the net primary productivity (NPP), crop production (CP), and wind protection and sand fixation (WPSF) of Horqin Sandy Land in 2025 under uncertain land use to identify the short board areas of various services. The following results were obtained from the analysis. (1) The land use pattern of Horqin Sandy Land in 2025 under the HT scenario will be dominated by cultivated land expansion and grassland reduction. Under the NP scenario, forest will increase, and unused land and grassland will decrease considerably. Under the WS scenario, cultivated land will still maintain a similar growth state, but the difference is that forest and grassland will significantly increase. (2) NPP had the highest probability of being the Highest and the lowest probability of being Low, whereas CP and WPSF obtained the highest probability of being Medium and the lowest probability of being Higher. (3) Tuquan County and Wengniute Banner with a high probability of providing few ecosystem services should be regarded as key areas for ecological restoration. Kailu County and Horqin Left-wing Middle Banner can provide higher ecosystem services. The methodology adopted in this study establishes the connection between the land use probability surface and the optimized pattern of ecosystem services and can therefore be applied in areas where multi-objective comprehensive improvement of ecosystem services is expected.

Owing to the increasing demand of environmentally benign materials for the degradation of hazardous dyes, herein we are reporting two different synthesis approaches for the fabrication of iron loaded bentonite composites by modifying and activating bentonite surface with polydopamine (PDA) followed by pillaring with Fe3+ (Fe-PDA-bentonite) and Fe3O4 (Fe3O4-PDA-bentonite). Both the composites were assessed for their adsorption and degradation performance using crystal violet (CV), Rhodamine B and Brilliant blue dyes following adopting advanced oxidation process type Fenton reaction under variable energy sources (Sunlight, UV light and Ultrasonication), concentration of H2O2 and catalyst dosage. Under UV light irradiation, the composites achieved complete degradation of the dyes within 60 min and showed degradation rate constant of 30.5E-3-81.8E-3. Textural characterizations of the composites were achieved via XRD, FTIR, TGA, XPS, SEM-EDX, TEM, N2 adsorption, VSM and UV/Vis spectrophotometry. The adsorption data of CV over the two composites fitted well with Langmuir adsorption isotherm, exhibiting the maximum adsorption capacity of 862 mg/g and 1235 mg/g for Fe-PDA-bentonite and Fe3O4-PDA-bentonite composites respectively. LCMS analysis of the post degradation products revealed that both the composites followed different degradation pathways and Fe3O4-PDA-bentonite showed superior photocatalytic performance by accomplishing complete dye degradation without leaving any degradation products. FTIR analysis of the post-degradation composites confirmed their structural stability with negligible iron leaching. This study, accredited to its cost-effectiveness, ease of operation and high efficiency, provides useful reference information for the degradation of dyes on industrial level.

Decontamination of dye loaded water has become an issue of intensive interest on both, basic research and industrial scale. Herein, we report the fabrication of bentonite/APTMA and Fe3O4-bentonite/APTMA adsorbents via a facile synthesis route and commonly available raw materials. The structural and morphological characteristics of the synthesized adsorbents were studied by BET, XRD, FTIR, VSM, SEM, EDX and XPS techniques and were tested for their adsorption capacity for cationic Crystal violet (CV) and anionic Congo red (CR) dyes. Fe3O4-bentonite/APTMA exhibited BET surface area and pore volume of 27.8 m2/g and 0.012 cm3/g respectively and superior adsorption than bentonite/APTMA with maximum calculated adsorption capacity of 2286 and 1210 mg/g for CV and CR respectively. Behavior of both the adsorbents revealed the hydrophobic nature of bentonite/APTMA which could be attributed to its lower adsorption capacity as compared to super-hydrophilic Fe3O4-bentonite/APTMA. Effect of operating parameters like pH, adsorbent dosage, dye concentration and temperature were studied, and it was observed that the efficiency of adsorbents was further enhanced towards dye removal in the presence of heavy metal ions and in model wastewater which was attributed to the synergistic effect of metal ions during adsorption process. Adsorption process was endothermic with fast reaction kinetics suggesting the predominant occurrence of chemisorption. Adsorption mechanism was dominated by the occurrence of hydrogen bonding and the electrostatic interactions between adsorbent and dye molecules. This study can be of great industrial prospects for the remediation of CR and CV and other similar dyes and organic pollutants from wastewater both, in the presence as well as absence of heavy metals ions.

Obtaining whispering gallery mode (WGM) lasing with prominent stability and high quality optical cavities is extremely desirable but still a great challenge. Despite the recent surge of reports on microspheres, nanowires and nanoplatelets metal halide crystals, there has few reports on the morphology of Hemispheres (HSs) in the form of uniform, component-tunable microcrystals. Here, CsPbX3 (X = Cl/Br) HSs with smooth surface and regular geometry structure were synthesized on silicon substrates by chemical vapor deposition (CVD) method, and the wavelength of laser can be continuously tuned from blue to green (450–540 nm) at room temperature by varying the halide composition. WGM laser with polarization ratio of 0.70 and cavity quality factor Q of 2485 were realized in the CsPbBr3 HS cavity. Besides, the crystal cavity suggested a high photonic and thermal stability for the superb capability of continuous stable lasing output under ambient conditions. All these results illustrate that the synthesis of cesium lead halide perovskite HSs may provide an alternative solution for fundamental researches and applications in optical devices.

Antibiotic contamination poses serious ecological and human health threats. To control these impacts, an economical and novel three-dimensional (3D) heterogeneous sodium dodecyl sulfate (SDS) modified BiOBr/magnetic bentonite (SDS/BiOBr-MB) with enhanced photocatalytic activity against tetracycline (TC) and ciprofloxacin (CIP) was fabricated via constructing flower-like BiOBr blossomed in the layered MB via a facile and mild approach. Compared with bare BiOBr, BiOBr-MB and SDS/BiOBr-MB catalyst owing to the introduction of magnetic Fe3O4/bentonite (MB) and parterre like structure, exhibited enhanced photocatalytic degradation activity of TC (85%) and CIP (95%). pH 6–8 favored higher photodegradation of TC and CIP using SDS/BiOBr-MB as compared to acidic or alkaline conditions. SDS/BiOBr-MB remained highly stabile and active for five consecutive reuses. The enhanced photocatalytic performance of SDS/BiOBr-MB was attributed to the presence of SDS, the n-n heterojunction between BiOBr and Fe3O4, and the introduction of bentonite which constructed a platform dispersing the growth of BiOBr. Through the function of SDS, BiOBr with the micro-flower shape having good adsorption ability and dispersing effect was self-assembled from nano-sheet-shaped BiOBr under hydrothermal conditions. The n-n heterojunction between BiOBr and Fe3O4 enhanced the separation and transfer efficiency of photo-generated electron-hole pairs of SDS/BiOBr-MB. The permanent negative charge on the surface of bentonite exhibited the ability to capture photo-generated holes and thus reduced the combination of photo-generated carriers. This study could provide valuable reference for the fabrication of new ternary visible-light responsive catalysts for the photodegradation of antibiotics and other organic pollutants.

The hotspot identification and interaction analyses of the provisioning of multiple ecosystem services (ESs) are basic prerequisites for sustainable ecosystem management. ESs and their interrelationships are determined by ecological processes over time and space. The high-value ES areas is crucial for regional land use management. However, most of hotspots identification are limited to a single point in time and/or in space. Here we proposed a framework for identifying a long-term stable supply area for multiple ESs, namely, an ES multifunctional area (ESMA) to recognize the region that can stably provide high-value ESs. Using Shaanxi Province as an example, four ESs, i.e., net primary productivity (NPP), soil conservation (SC), water yield (WY), and habitat quality (HQ), were quantified from 2000 to 2015 at a pixel scale of 1 km. Then, we identified ESMA in Shaanxi and explored the trade-offs and synergies among ESs within and outside ESMA. Results of the study provided the following conclusions: (1) With the exception of WY, ESs exhibit apparent spatial differentiation in areas bounded by the Qinling Mountains due to terrain and climate differences between the north and south of these mountains. (2) The ES supply areas of NPP accounted for 41.47% of the total area of Shaanxi Province. This finding indicates the NPP provision was relatively stable. (3) The ESMA of Shaanxi Province is largely situated in southern Shaanxi. The primary land use types of ESMA are forest and grassland, and the areas that provide NPP, HQ, and SC services are the largest among all service combinations. (4) The trade-offs and synergies of ESs are more stable in ESMA than those in non-ESMA. This study proposes to provide a long-term provision of multiple stable high-value ESs to a priority protected area, thereby offering support and services for the development of ecosystem differential spatial protection policies.

In this study, we designed the luminescent enhanced composites by combining upconversion nanoparticles (UCNPs) and photonic crystals (PCs), and prepared multi-mode coding patterns through utilizing the optical properties of both materials, respectively. We prepared UCNPs with different luminescence and the composite materials can be quickly obtained by spin-coating the UCNPs on the surface of the PCs. We discover that the composite materials have significant luminescent enhancement and the enhancement of upconversion is attributed to the Bragg reflection of the photonic band gap. We fabricated upconversion luminescent lattices based on the surface of the PCs by dropping and endowed with the meaning of the Morse code so that it can have more information in different modes. In addition, we further obtained the cipher table pattern according to the structural color of the PCs and the luminescence of the UCNPs. The results reveal great potential applications in the field of multi-mode optical imaging and anti-counterfeiting.

Eco-compensation is an important mechanism when applying the theory of ecosystem services to practical development, which translates the external and non-market value of the environment into real financial incentives for local actors. Scientifically formulating feasible and credible compensation standards is the most critical and key step to adjusting the benefits received by environment protectors and beneficiaries. The Inner Mongolia agro-pastoral zone is an important ecological area with an undeveloped economy in Northern China. The implementation of eco-compensation policies contributes to ecological restoration and poverty alleviation. Taking Horqin Left Back Banner, Inner Mongolia, China as a study case, a quantitative model of a non-point source pollution eco-compensation program was established by using emergy synthesis&mdash, a thermodynamics-based method in ecological economic systems&mdash, to create a comprehensive eco-compensation standard. The results showed that the eco-compensation amounts for non-point source pollution were generally below 10% of the regional gross domestic product (GDP). A 11&ndash, 20% reduction in fertilizer would be accepted according to the field investigation and the optimal eco-compensation strategy reduced the phosphate fertilizer application by 20% with a compensation standard of $379.63/ha/year, which was similar to the farmers&rsquo, willingness to accept compensation. For the accurate creation of a non-point source pollution eco-compensation program, the emergy synthesis overcomes the inconsistency in the quantification of the material flow, ecological flow, and economic flow, guaranteeing the sustainable implementation of non-point source pollution eco-compensation projects.