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It is widely recognized that the synergistic effects during co-gasification process of coal and biomass are caused by the inherent alkali/alkaline earth metals (AAEM). However, the compositions of biomass and coal are complex, with main components being not only AAEM, but also aromatic, aliphatic, and heteroatom-containing compounds. Therefore, whether these organic components can also result in synergistic effects during co-gasification is necessary to be investigated. In this work, to reveal the reaction characteristics of organic components in co-gasification process, two raw materials with little content of ash were selected. The gasification behaviors of coal and biomass were studied and the influences of blending ratio and gasification temperature were mainly examined. The results showed that gasification reactivity of pure biomass was the strongest and its carbon conversion reached 100% within 33 min. With the increase of biomass ratio, gasification reactivity of mixtures was gradually enhanced, which could be ascribed to active functional groups, porous structures, and incompact macromolecular structures of biomass. At high temperature, the gasification reactivity difference was lessened among different samples. As for coal, the reactivity index at 800°C was 0.012. With the increase of biomass blending ratio from 25% to 100%, the reactivity index slowly went up to 0.023 at maximum. When temperature rose to 900°C, the reactivity index was enlarged nearly eight times compared with that of 800°C. At temperatures tested, the shrinking core mode was appropriate to describe gasification process, especially for coal and coal/biomass mixtures. Kinetic analysis showed the theoretical activation energies were all higher than the experimental values, indicating that the interaction between coal and biomass diminished activation energy. The synergy index suggested that gasification reactivity of coal was indeed enhanced during co-gasification process. However, a high-temperature environment might cover up the positive roles of biomass and the synergistic effect was hence weakened. In conclusion, the synergistic effects during co-gasification process could be induced by the organic components in coal and biomass. [ABSTRACT FROM AUTHOR]

Flexible and foldable electronic products often contain adhesive layers, and failure generally initiates at the adhesive interfaces. To analyze the interfacial stress accurately, correct constitutive relationship of adhesive layers is necessary. However, soft adhesives used in foldable sandwich plates can show rate-dependent and anisotropic mechanical behaviors, which can hardly be implemented by traditional linear elastic and hyperelastic constitutive models in the folding process simulation. Through experiments in material's principal axes and the strain energy equivalence principle, a transversely isotropic and rate-dependent constitutive relationship of adhesive has been developed in a three-dimensional form. By commercial finite element (FE) software ABAQUS and its user subroutine UMAT, the folding stress of a sandwich plate has been analyzed. The results of FE simulation show that folding time would affect stress distributions significantly due to the anisotropic and rate-dependent properties of adhesive. [ABSTRACT FROM AUTHOR]

Given the ability of effectively observing vegetation at a variety of spatial and temporal scales, remote sensing has been widely used to monitor and understand the change of mangrove forest extent. Yet, a systematic cognition of the unique contribution of remote sensing on studying mangrove forest extent dynamic is lacking, which prevents us from clearly identifying and further overcoming current deficiencies of studying the change of mangrove forest extent with remote sensing. Therefore, in this review, we summarized remotely sensed extraction methods and data related to mangrove forest extent change monitoring and all discoveries from mangrove forest extent change observation and driver analysis. We found that mangrove forest in most of the study areas has declined over the past decades, and the loss rate is accelerating. We also found that remote sensing plays an important role in revealing how the extent of mangrove forest responds to climate change and human impacts. In addition, we identified several recurring limitations from previous studies. This review highlights the role of remote sensing on studying mangrove forest extent change, and is helpful to make better use of remotely sensed data in this field. [ABSTRACT FROM AUTHOR]

Since the launch of the first land-observation satellite (Landsat-1) in 1972, land-cover mapping has accumulated a wide range of knowledge in the peer-reviewed literature. However, this knowledge has never been comprehensively analysed for new discoveries. Here, we developed the first spatialized database of scientific literature in English about land-cover mapping. Using this database, we tried to identify the spatial temporal patterns and spatial hotspots of land-cover mapping research around the world. Among other findings, we observed (1) a significant mismatch between hotspot areas of land-cover mapping and areas that are either hard to map or rich in biodiversity; (2) mapping frequency is positively related to economic conditions; (3) there is no obvious temporal trend showing improvement in mapping accuracy; (4) images with more spectral bands or a combination of data types resulted in increased mapping accuracies; (5) accuracy differences due to algorithm differences are not as large as those due to various types of data used; and (6) the complexity of a classification system decreases its mapping accuracy. We recommend that one way to improve our understanding of the challenges, advances, and applications of previous land-cover mapping is for journals to require area-based information at the time of manuscript submission. In addition, building a standard protocol for systematic assessment of land-cover mapping efforts at the global scale through international collaboration is badly needed. [ABSTRACT FROM PUBLISHER]

Two novel compounds [Zn(bip)(BDC)] (1) and [Co(bip)2Cl2· 4H2O] (2) [bip = 2-(4-bromophenyl)-1H-imidazo[4,5-f][1,10]phe- nanthroline, BDC = phthalate acid] have been synthesized by hydrothermal reactions and characterized by elemental analysis, thermogravimetric (TG) analysis, infrared spectrum (IR), and single-crystal X-ray diffraction. Single-crystal X-ray diffraction reveals that compounds 1 and 2 are zero-dimensional (0D) architecture, and the existence of hydrogen bonds and π-π interactions lead the 0D to 2D novel frameworks. Hydrogen bonds and π-π interactions are powerful interactions for directing supramolecular architectures. TG analysis shows clear courses of weight loss, which corresponds to the decomposition of different ligands. The luminescent properties for the ligand bip and compounds 1–2 are also discussed. [ABSTRACT FROM AUTHOR]