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In our previous work, a family of isostructural lanthanide metal-organic frameworks, [Ln3(L)3(H2O)2]·(H3O)3·(H2O)4·(DMF)3 (abbreviated as Ln3(L)3(H2O)2, Ln = Eu, Tb, Sm, Dy and Gd) were synthesized under solvothermal conditions based on a semi-rigid tetravalent carboxylic tetracarboxylic acid (3,3′,5,5′-biphenyltetracarboxylic acid, H4L). Due to the good sensitization of the H4L ligand, Ln3(L)3(H2O)2 all show the intense characteristic emission bands of the corresponding lanthanide ions. The optical properties of Ln3(L)3(H2O)2 can be easily tuned by doping different lanthanide ions into the same host frameworks. Moreover, white-light emission can be successfully realized for four kinds of codoped compounds Tb0.005Eu0.005Gd0.990L, Dy0.006Eu0.006Gd0.988L, Dy0.0002Sm0.001Gd0.9988L and Tb0.002Sm0.006Gd0.992L (the value refer to the starting molar ratios of Ln3+ ions).

There is a growing recognition of the broader environmental significance of exploring the relative importance of climate change and anthropogenic impacts on hydrologic fluctuations in river-lake systems. In the case of Dongting Lake, the typical river-lake system, we collected the water level from 1990 to 2019, spanning before and after the operation of the Three Gorges Dam (TGD) in 2003. This study was conducted to detect water level fluctuations in Dongting Lake and to quantify the relative influence of climate, land cover and dam construction on water levels. We defined the impact of the dam construction as the three inlets inflow of Yangtze River (In-YR), and four waters inflow of Hunan (In-HN). The Mann-Kendall (M-K) test revealed the trends and change points of water level fluctuations. Structural Equation Model (SEM) was used to detect the direct and indirect effects of these factors on water level and quantify their relative importance. The MIKE21 hydrodynamic model reflected the spatial-temporal variability of water levels under the action of key driver. The results showed that the water level appeared a downward trend during 1990-2019 and the change point appeared in 2003; During 1990-2002, the significant factors were: precipitation (V = 0.469, P = 0.013), evaporation (V = -0.424, P = 0.029), non-agricultural cover (V = -0.334, P = 0.025), and agricultural cover (V = 0.235, P = 0.033); During 2003-2019, the significant factors were: In-YR (V = 0.436, P = 0.007), In-HN (V = 0.431, P = 0.012), and precipitation (V = 0.349, P = 0.045); The In-YR was the key factor affecting the changes of the water level during 1990-2019; Under the influence of In-YR, the most obvious fluctuation of water level was in the flood adjustment period (Jun-Aug) and the impoundment period (Sep-Nov) when the average declined by about 0.50 and 0.67 m, respectively. Our findings provide a new insight into how to better maintain the stability of river-water system water resources under the influence of multiple factors.

Recently, layered bismuth oxyhalides (BiOX) have been a well-deserved hotspot in the field of photocatalysis owning to their fascinating physicochemical properties derived from unique layered structures. Nevertheless, insufficient sunlight absorption, rapid recombination of electron-hole (e--h+) pairs, finite carrier concentration, and weak interaction between BiOX surface and reactant molecules inevitably limit the photocatalytic performance of BiOX. Given this, vacancy engineering, which can unleash the great potential to manipulate crystal and electronic structures and surface chemistry of BiOX, is widely applied to improve BiOX to meet the increasingly diverse theoretical and applicable needs. In this review, we focus on recent development in the design of appropriate vacancies on the BiOX for photocatalytic application. The introduction and analysis of popular vacancies creating approaches for BiOX and techniques to distinguish various vacancies are provided. The inherent functionality of BiOX vacancies in photocatalysis at the molecular level is clarified. Then we present representative photocatalytic applications, performance, and corresponding vacancy behavior of vacancy-mediated BiOX. Finally, based on an unambiguous understanding of the vacancy–property relationships and a complete view of the state of the art of vacancy-mediated BiOX, the future directions and possibilities for the rational design of vacancies to acquire ideal properties are explored.

Climate changes are related to the changes in the distribution of migratory species, which irreparably harm biodiversity. In this study, we evaluated the habitat change and population centroid shift for 7 orders and 23 different species on the IUCN (International Union for the Conservation of Nature and Natural Resources) Red List of migratory birds from 2014 to 2017 in current to mid-21st (2041–2700) century by Maximum Entropy method (MaxEnt) model. We found that there is significant spatial variability in geographical suitability, with the Yangtze River basin losing 9.74% of suitable habitat and the Pearl River basin losing 13% of habitat. The area of suitable habitat decreases over 3% of total habitat area in China under the RCP 2.6, and decreases about 10% of total habitat area in China under RCP 8.5 scenario, with the population centroid of habitat moving about 50 km to northeast on average. Furthermore, the mean suitability of migratory birds will decrease over 3% in the future, which means environmental variables are changing in directions that are not suitable for birds. Migratory birds will change their habitat and growth cycle in response to the climate change. The direction and distance of the population centroid are different for every species. Most of the individual species in the study will move over 50 km and all the species will move to places with higher suitability. For the whole of China, the constraint for migratory birds is t min (Minimum temperature). The dominant variable in southeast China is NDVI (Normalized Difference Vegetation Index), while alt (altitude) in the north China. The decline in the suitable habitat area and shift in the population centroid will lead to the changes in the time and distance of the migration process, resulting in more adverse conditions for the survival of migratory birds. Our study proves the adverse role of climate change in species distribution which is a prerequisite for protecting species in the future.

A new three-dimensional manganese-based metal–organic framework Mn4L2(HL)(H2O)5, (1), based on semi-rigid 5-((4′-(tetrazol-5′’-yl)benzyl)oxy)isophthalic acid ligand (H3L) have been prepared and characterized under solvothermal condition. In the structure of 1, trinuclear Mn3O13N2 units are linked each other by sharing vertex and edge to form left- and right- hand helical O-Mn-O chains along b axis, then adjacent left and right handed helical chains are interconnected by L3− and HL2− ligands to generate a 2D layer and L3− ligands with mode II connect the neighboring layers to form a 3D network. 1 shows high stability under different pH conditions and various organic solvents. After activation, 1 exhibits excellent catalytic properties for two typical C C bond reactions, cyanosilylation and Knoevenagel condensation reaction of aldehydes, under solvent-free conditions at room temperature.

Sc-CP 1, 1A, 1B and 1C with controllable morphologies were successfully synthesized by the conventional hydrothermal method and microwave (MW) assisted hydrothermal method. 1 was macroscopic, 1A was nano sized, while 1B and 1C were micron sized. Sc-CP 1 showed two-dimensional (2D) layered structure which was constructed from the connections of left- and right-hand helical chains. Catalytic experiments showed the catalytic performances of Sc-CP 1, 1A, 1B and 1C for the cyanosilylation reaction of aromatic aldehydes were dependent on the morphologies of the particles. Flower-ball-like 1C featuring a high concentration of Lewis acidic Sc(III) sites on its exposed external surfaces showed better catalytic activity than others, the best constant rate of which was 6.4 ​× ​10−3 min−1.

Two new three-dimensional (3D) Sc(III)-based metal organic frameworks (MOFs) [Sc2(OH)2(TDC)2]·4H2O (1) and [Sc3O(fum)3(H2O)3(NO3)]·DMF (2) (H2TDC = 2,5-thiophenedicarboxylic acid, H2fum = fumaric acid) have been hydrothermally synthesized. For 1, TDC2− ligands connect infinite one-dimensional (1D) -Sc-OH-Sc-OH- chains to form open-framework with rhombic channels along the a axis. In 2, flexible fum2− ligands link adjacent trimer [Sc3O(COO)6(H2O)3] secondary building units showing hexagonal-closed circular pores with a diameter of approximate 9.9 A. Furthermore, the desolvated material la can retain the framework, presenting good catalytic activity, significant universality and substrate-selectivity for Strecker-type reactions of trimethylsilyl cyanide (TMSCN) and various aromatic aldimines, especially for N-benzyl 4-methoxybenzaldimine.