Lake shrinkage-induced terrestrial ecological environmental quality degradation in a semiarid lake basin.

Lake water environmental problems caused by lake shrinkage in semiarid zones have attracted widespread attention, but few studies have quantified the impact of lake shrinkage on the terrestrial ecological environmental quality of watersheds. In this study, remote sensing image inversion, digital elevation modeling, and statistical analysis were applied to explore the impact of Lake Daihai shrinkage on the terrestrial ecological environmental quality of its receding water areas from 1986 to 2019. The results showed that the area of Lake Daihai shrank from 170.

Defect Passivation and Lithium Ion Coordination Via Hole Transporting Layer Modification for High Performance Inorganic Perovskite Solar Cells.

Metal halide inorganic perovskite solar cells (PSCs) have great potential to achieve high efficiency with excellent thermal stability. However, the surface defect traps restrain the achievement of high open circuit voltage (V ) and power conversion efficiency (PCE) of the devices due to the severe nonradiative charge recombination. Moreover, the state-of-the-art hole transporting layer (HTL) significantly hampers device moisture stability, even though it renders the highest solar cell efficiency.

Strengthened Surface Modification for High-Performance Inorganic Perovskite Solar Cells with 21.3% Efficiency.

Metal halide inorganic perovskites show excellent thermal stability compared to organic-inorganic perovskites. However, the performance of inorganic perovskite solar cells (PSCs) is far from theoretical values, together with unsatisfactory stability, mainly due to the poor interfacial properties. In this work, a facial but effective method is reported to realize high-performance inorganic PSCs by post-modifying the perovskite surface with 2-thiophene ethylamine (TEA).

Tailored Cysteine-Derived Molecular Structures toward Efficient and Stable Inorganic Perovskite Solar Cells.

Surface-defect-triggered non-radiative charge recombination and poor stability have become the main roadblock to continued improvement in inorganic perovskite solar cells (PSCs). Herein, the main culprits are identified on the inorganic perovskite surface by first-principles calculations, and to purposefully design a brand-new passivator, Boc-S-4-methoxy-benzyl-l-cysteine (BMBC), whose multiple Lewis-based functional groups (NH, S and CO) to suppress halide vacancies and coordinate with undercoordinated Pb through typical Lewis baseacid reactions. The tailored electron-donating methoxyl group (CH O-) can cause an increased electron density on the benzene ring, which strengthens the interaction with undercoordinated Pb via electrostatic interactions.

Lead(II) 2-Ethylhexanoate for Simultaneous Modulated Crystallization and Surface Shielding to Boost Perovskite Solar Cell Efficiency and Stability.

The bulk and surface of a perovskite light-harvesting layer are two pivotal aspects affecting its carrier transport and long-term stability. In this work, lead(II) 2-ethylhexanoate (LDE) is introduced via an antisolvent process into perovskite films to change the reaction kinetics of the crystallization process, resulting in a high-quality perovskite film. Meanwhile, a carboxyl functional group with a long alkyl chain coordinates with the Pb cation, reducing the defect density related to unsaturated Pb atoms.

Establishment and Application of a Predictive Growth Kinetic Model of with the Appearance of Two Other Dominant Background Bacteria in Fresh Pork.

To better guide microbial risk management and control, growth kinetic models of with the coexistence of two other dominant background bacteria in pork were constructed. Sterilized pork cutlets were inoculated with a cocktail of Derby ( Derby), (), and Escherichia coli (), and incubated at various temperatures (4-37 °C). The predictive growth models were developed based on the observed growth data.

Chelate Coordination Strengthens Surface Termination to Attain High-Efficiency Perovskite Solar Cells.

Solar cell efficiency and stability are two key metrics to determine whether a photovoltaic device is viable for commercial applications. The surface termination of the perovskite layer plays a pivotal role in not only the photoelectric conversion efficiency (PCE) but also the stability of assembled perovskite solar cells (PSCs). Herein, a strong chelate coordination bond is designed to terminate the surface of the perovskite absorber layer.

Polar Species for Effective Dielectric Regulation to Achieve High-Performance CsPbI Solar Cells.

Nonradiative losses caused by defects are the main obstacles to further advancing the efficiency and stability of perovskite solar cells (PSCs). There is focused research to boost the device performance by reducing the number of defects and deactivating defects; however, little attention is paid to the defect-capture capacity. Here, upon systematically examining the defect-capture capacity, highly polarized fluorinated species are designed to modulate the dielectric properties of the perovskite material to minimize its defect-capture radius.

Analysis of Key Control Points of Microbial Contamination Risk in Pork Production Processes Using a Quantitative Exposure Assessment Model.

Pork is one of the most common foods causing microbial foodborne diseases. Since pork directly enters the market after slaughtering, the control of microbial contamination in the slaughtering processes is the key to ensuring the quality and safety of pork. The contamination level of , a health-indicator bacterium, can reflect the risk level of potential pathogens.

Strong spring winds accelerated the recruitment and reinvasion of cyanobacteria.

The reinvasion and recruitment of overwintering cyanobacteria in sediments in spring have an important impact on cyanobacterial blooms in summer and autumn, but until now, this process has not been observed in natural water bodies. In this study, wireless sensors and automatic water sample collection systems were used to carry out continuous high-frequency monitoring of cyanobacteria and related environmental indicators in Meiliang Bay, Lake Taihu, during a northwest wind event in spring. The results showed that there were many dormant cyanobacteria seeds in the sediments of Lake Taihu.

In-situ observations of internal dissolved heavy metal release in relation to sediment suspension in lake Taihu, China.

Despite laboratory experiments that have been performed to study internal heavy metal release, our understanding of how heavy metals release in shallow eutrophic lakes remains limited for lacking in-situ evidence. This study used automatic environmental sensors and a water sampling system to conduct high-frequency in-situ observations (1-hr intervals) of water environmental variables and to collect water samples (3-hr intervals), with which to examine the release of internal heavy metals in Lake Taihu, China. Under conditions of disturbance by strong northerly winds, sediment resuspension in both the estuary area and the lake center caused particulate heavy metal resuspension.

An Outer Membrane Protein Involved in the Uptake of Glucose Is Essential for Cytophaga hutchinsonii Cellulose Utilization.

Cytophaga hutchinsonii specializes in cellulose digestion by employing a collection of novel cell-associated proteins. Here, we identified a novel gene locus, CHU_1276, that is essential for C. hutchinsonii cellulose utilization.

A small periplasmic protein essential for Cytophaga hutchinsonii cellulose digestion.

Cytophaga hutchinsonii is a gliding cellulolytic bacterium that is ubiquitously distributed in soil. The mechanism by which C. hutchinsonii achieves cellulose digestion, however, is still largely unknown.

Outer membrane proteins related to SusC and SusD are not required for Cytophaga hutchinsonii cellulose utilization.

Cytophaga hutchinsonii, a member of the phylum Bacteroidetes, employs a novel collection of cell-associated proteins to digest crystalline cellulose. Other Bacteroidetes rely on cell surface proteins related to the starch utilization system (Sus) proteins SusC and SusD to bind oligosaccharides and import them across the outer membrane for further digestion. These bacteria typically produce dozens of SusC-like porins and SusD-like oligosaccharide-binding proteins to facilitate utilization of diverse polysaccharides.

Identification and characterization of a novel locus in Cytophaga hutchinsonii involved in colony spreading and cellulose digestion.

Cytophaga hutchinsonii, an aerobic cellulolytic soil bacterium, is capable of degrading crystalline cellulose and gliding over surface rapidly. The involved mechanisms, however, are largely unknown. Here, we used the mariner-based transposon HimarEm1 to screen for C.