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Bismuth telluride (Bi 2 Te 3) is a widely used thermoelectric (TE) material in practical applications. However, it contains expensive and toxic tellurium, a promising TE material should include low-cost and non-toxic element. Bismuth selenide (Bi 2 Se 3) is similar to Bi 2 Te 3 in electronic and crystal structure. The electron effective mass of Bi 2 Se 3 is smaller than that of Bi 2 Te 3 , while its electrical transport performance is inferior to that of Bi 2 Te 3. Therefore, in this study, Cl and K co-doped Bi 2 Se 3 thermoelectric material with high density, low thermal conductivity, and excellent thermoelectric performance was prepared using KCl as the solvent. It is found that the effective electron mass and carrier concentration of the doped sample is effectively improved, which significantly increases the doped sample's electrical transport properties and ZT value. Finally, the Bi 2 Se 3 (KCl) 3.5 sample reached a maximum ZT value of 0.79 at 550 K, and the average ZT in the measured temperature range reached 0.45. [ABSTRACT FROM AUTHOR]

With the progression of urbanization and the concentration of populations in urban areas, cities are increasingly exposed to disaster risks. Emergency shelters play a critical role in disaster prevention and mitigation, as they are vital for providing temporary refuge and protection during and after catastrophic events. Assessing the spatial equity of these shelters is conducive to enhancing emergency relief capabilities and aiding in disaster risk reduction. However, there remains a lack of clarity regarding the comparative and quantitative disparities between new and old urban areas, particularly in developing countries like China, where urbanization is rapid and populations are dense. To address this issue, this study employed a combination of multi-source data and GIScience technology to analyze the spatial equity of emergency shelters in Wuhua District and Chenggong District of Kunming City, China. We evaluated the overall spatial equity of emergency shelters in both the old urban area (Wuhua District) and the new urban area (Chenggong District) using a comprehensive evaluation model with three criteria: evacuation population capacity, spatial accessibility, and the level of per capita effective shelter area. The results revealed that the old urban area suffers from insufficient effective emergency shelter capacity due to saturated construction land. More than 67 % of the shelters are short-term emergency shelters located close to buildings, which compromises spatial accessibility during earthquake disasters. The level of per capita effective shelter area, as indicated by S S T D , is 24.42 in Wuhua District, suggesting that the effective shelter area in each subdistrict is consistently low, regardless of its urban or suburban classification. In contrast, the new urban district boasts substantial effective emergency shelter capacities, both in the long-term and short-term types, surpassing the reference capacities. The rational spatial layout of various types of emergency shelters ensures that most regions with concentrated buildings are enveloped in accessibility time layers within a 25-min range. The S S T D index of Chenggong District is 349.23, underscoring the significant disparity in the level of per capita effective shelter area at the subdistrict scale, particularly in the district's urban villages and suburban regions. The findings of this study serve as a scientific reference for emergency management and urban planners to reasonably plan or upgrade shelter facilities, thereby improving urban resilience and promoting spatial equity in resource allocation among subdistricts, communities, and residents. [ABSTRACT FROM AUTHOR]

• Evaluate the urban resilience from a multidimensional perspective. • Validate and analyze by using NPP-VIIRS nighttime light data. • The average urban resilience index increased from 0.027 to 0.058 from 2011 to 2021. • The coefficient of variation decreased from 0.823 in 2011 to 0.751 in 2021. • The moran's i of urban resilience increased from 0.2017 in 2011 to 0.4476 in 2021. Modern cities are facing increasingly complex challenges, and assessing urban resilience is crucial to improve their ability to withstand various types of shocks and disasters, especially in the China's North-South Seismic Belt with frequent tectonic activities and natural disasters. To address this issue, this study determined the weights of the assessment system based on the entropy weight method, and evaluated the urban resilience of four provinces in China's North-South Seismic Belt in multiple dimensions from the perspectives of society, economy, infrastructure, and ecology. Furthermore, we systematically explored the spatiotemporal trends of urban resilience and its spatial correlation from 2011 to 2021. Lastly, the assessment results were validated and analyzed by four historical earthquake cases using national polar-orbiting partnership - visible infrared imaging radiometer suite (NPP-VIIRS) nighttime light data. The findings reveal that the average urban resilience index increased from 0.027 to 0.058 from 2011 to 2021, signifying a remarkable surge of 115.42%. Sichuan emerged as a consistent frontrunner in terms of urban resilience. Overall, the study area shows a spatial distribution pattern of higher urban resilience in the east and lower resilience in the west, due to the larger population and more developed economy in the east. However, the south has a higher average annual growth rate, while the north has a lower average annual growth rate. A notable observation is the gradual reduction in the coefficient of variation of urban resilience from 0.823 in 2011 to 0.751 in 2021, indicating a decline in the disparity of resilience levels. Meanwhile, Moran's I gradually increased from 0.2017 in 2011 to 0.4476 in 2021, signifying a progressive intensification in the spatial correlation of urban resilience and an evident propensity toward aggregation. By selecting shifts in the total nighttime light index (TNLI) during representative earthquake incidents as an indirect gauge of urban resilience levels, this study finds congruence with the assessment outcomes, thereby further substantiating the precision of the urban resilience evaluations. Policymakers should prioritize the allocation of resources to less resilient cities to improve their ability to withstand and recover from disaster events. The urban resilience assessment system in this study, despite its multidimensionality, may still not be able to fully cover all the factors affecting urban resilience. This study provides a significant decision-making basis for policymakers in urban development and disaster response, as well as a useful reference for building a more robust and sustainable urban future. [ABSTRACT FROM AUTHOR]

Highlights • ABA and NO improved tall fescue low-light tolerance. • ABA mediated antioxidant defense and photosynthesis under low-light stress. • ABA elevated NO level through enhancing NOS-like activity and up-regulating FaNOA1 expression. Abstract Abscisic acid (ABA) and nitric oxide (NO) are both extremely important signalling molecules employed by plants to mediate plant tolerance under abiotic stresses. In the present study, the role of NO in ABA-induced photosynthesis and antioxidant system in leaves of tall fescue ( Festuca arundinacea Schreb.) seedlings was investigated. Low-light (LL) stress increased intercellular CO 2 concentration ( Ci ), as well as decreased plant height, leaf width, tiller number, biomass, chlorophyll content, net photosynthetic rate ( Pn ), stomatal conductance ( Gs ), transpiration rate ( Tr ), the maximum quantum yield of photosystem photochemistry ( F v / F m ), actual photochemical efficiency of photosystem II ( Φ PSII ), photochemical quenching (qP), the apparent electron transport rate (ETR), enzymatic activity of ribulose-1,5-bisphosphate carboxylase (Rubisco) and glyceraldehyde phosphate dehydrogenase (GADPH) and phosphoribulokinase (PRK), which were substantially alleviated by exogenous ABA application. Moreover, application of these leaves with exogenous ABA resulted in reduced LL stress induced ion leakage and reduced contents of MDA, H 2 O 2 and superoxide radicals O 2 • - , as well as higher activities of peroxidase (POD), superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX). Expression of genes coding antioxidant enzymes increased in tall fescue in the presence of ABA under LL stress. These responses could be reversed by treatment with fluridone (the ABA biosynthesis inhibitor). The application of ABA elevated NO level, enhanced nitric oxide synthase (NOS)-like activity and up-regulated the tall fescue nitric oxide synthase-associated gene, NITRIC OXIDE ASSOCIATED 1 ( FaNOA1 ) expression level. In addition, neither exogenous NO nor specific NO scavenger 2-(4-carboxy-2-phenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO) or NO synthase (NOS) specific inhibitor N ω-nitro- L -arginine (LNNA) treatments had no effect on endogenous ABA concentration and ABA receptors transcript levels ( FaPYR1 and FaPYL1 ), implying that the protective effect of ABA under LL stress might be mediated by NO. These results indicated that NO was involved in the ABA-mediated LL tolerance via regulating the antioxidant defense system and keeping a high level of photosynthetic rate in tall fescue. [ABSTRACT FROM AUTHOR]

Previous studies have found that participants use two cognitive strategies—constructive matching and response elimination—in responding to items in the Raven's Advanced Progressive Matrices (APM). This study proposed a multi-strategy psychometric model that builds on item responses and also incorporates eye-tracking measures, including but not limited to the proportional time on matrix area (PTM), the rate of toggling (ROT), and the rate of latency to first toggle (RLT). By jointly analyzing item responses and eye-tracking measures, this model can measure each participant's intelligence and identify the cognitive strategy used by each participant for each item in the APM. Several main findings were revealed from an eye-tracking-based APM study using the proposed model: (1) The effects of PTM and RLT on the constructive matching strategy selection probability were positive and higher for the former than the latter, while the effect of ROT was negligible. (2) The average intelligence of participants who used the constructive matching strategy was higher than that of participants who used the response elimination strategy, and participants with higher intelligence were more likely to use the constructive matching strategy. (3) High-intelligence participants increased their use of the constructive matching strategy as item difficulty increased, whereas low-intelligence participants decreased their use as item difficulty increased. (4) Participants took significantly less time using the constructive matching strategy than the response elimination strategy. Overall, the proposed model follows the theory-driven modeling logic and provides a new way of studying cognitive strategy in the APM by presenting quantitative results. • The multi-strategy eye-tracking model can measure intelligence and identify strategy. • High-intelligence people are likely to use constructive matching. • Low-intelligence people tend to use response elimination for difficult items. • The proportional time on matrix has the greatest effect on the strategy selection. [ABSTRACT FROM AUTHOR]

In recent years, with the acceleration of urbanization and abnormal changes in the overall climate, cities have been increasingly threatened and affected by disasters. Assessing and improving urban resilience, as well as postdisaster recovery monitoring, are of great significance for relevant municipal departments. Taking the heavy rainstorm event that occurred on July 20, 2021, in Zhengzhou City as an example, this study explored the resilience and postdisaster recovery of Zhengzhou City based on remote sensing data and other multisource data. First, we calculated the resilience assessment index and built an assessment model. Then, we analyzed and evaluated the resilience. Finally, based on NPP-VIIRS nighttime light data, we verified the accuracy of the resilience results and dynamically monitored the postdisaster recovery process. The results show that the overall resilience of Zhengzhou City to waterlogging disasters is low in the southwest and high in the northeast. The changing trend of the nighttime light brightness following the disaster was consistent with the resilience assessment results. Then, due to rescue work, the light index increased briefly in July; Due to the serious impact of the disaster, the facilities were damaged, and the light index was reduced in August. With the development of recovery work, the disaster-influenced and light index areas gradually recovered and exceeded the predisaster level. Corresponding urban resilience strategies were proposed based on the assessment results. This study can provide a scientific basis and reference for relevant aspects such as disaster prevention, recovery, and reconstruction in Zhengzhou City and other cities. [ABSTRACT FROM AUTHOR]

The impacts of changes in hydraulic retention time (HRT) on nitrogen elimination, the activity of sludge and the structure of microbial communities in a sequencing batch reactor under the joint stress of ibuprofen (IBP) and ciprofloxacin (CIP) were investigated. Under the combined stress of IBP (belonged to nonsteroidal anti-inflammatory drugs) and CIP (belonged to antibiotics), the elimination level of ammonia nitrogen, chemical oxygen demand, and the rate of specific ammonia oxidation, specific nitrite oxidation, specific nitrate reduction in activated sludge declined with the shortening of HRT. Under the joint stress of IBP and CIP, the content of polysaccharide (PS) and protein (PN) together with the ratio of PN to PS in the extracellular polymeric substances grew with the shortening of HRT, and the content of aromatic proteins increased significantly, which indicated that aromatic proteins were the major protective response substances to the shortening of HRT. Under the joint stress of IBP and CIP, with the reduction of HRT, and the reduction rate of relative abundance of nitrifying bacteria was more evident than that of denitrifying bacteria. This exploration gives novel thoughts for understanding the impacts of HRT on biological nitrogen removal of wastewater under combined stress of IBP and CIP. [ABSTRACT FROM AUTHOR]

Evaluating regional ecological environmental quality (EEQ) using remote sensing is important for achieving sustainable development. The remote sensing ecological index (RSEI) is a typical EEQ evaluation model used to comprehensively reflect regional ecological quality. However, owing to its complete dependence on remote sensing image information, the RSEI also has inherent issues, including unstable time series and inconsistent resolutions of its four sub-indices. To address these problems, this study used the Google Earth Engine (GEE) to propose an optimisation notion for the harmonic analysis of time series (HANTS) coupled random forest (RF) model and determined the accuracy and image quality of the optimised RSEI (RSEI o) for the Yangtze River Basin (YRB). Based on the findings, HANTS could fill the gaps in the images, effectively reducing the noise and discrete degrees of the four indices and thereby improving the stability of the RSEI. The correlation coefficient (R) between the RSEI and RSEI o was 0.93, with a root mean square error (RMSE) of 0.13, indicating that RSEI o is reliable. The image quality assessment (based on contrast and information entropy) indicates that HANTS combined with the RF model can produce RSEI o images with higher definitions and richer information at a constant spatial resolution. Further, the pixel-by-pixel coefficient of variation evaluation indicates that the RSEI o image was highly stabilised, yielding higher numbers of effective RSEI o images without changing the temporal resolution. Compared with traditional RSEI calculations, the optimisation proposal herein could highlight ecological differences caused by topographic changes in the YRB, which would produce an RSEI closer to actual surface conditions. Further, this proposed method could be used to obtain more detailed ecological information at a constant spatiotemporal resolution, thereby meeting the needs of long-term ecological monitoring in large-scale regions. • Fill the gaps of RSEI image and improve the stability of its time series. • Generate images with more informative EEQ at constant spatiotemporal resolution • The optimised RSEI (RSEI o) is more suitable for dynamic analysis. [ABSTRACT FROM AUTHOR]

Abstract: The influence of yttrium on the corrosion residual strength of an AZ91D magnesium alloy was investigated detailedly. Scanning electron microscope was employed to analyze the microstructure and the fractography of the studied alloys. The microstructure of AZ91D magnesium alloy is remarkably refined due to the addition of yttrium. The electrochemical potentiodynamic polarization curve of the studied alloy was performed with a CHI 660b electrochemical station in the three-electrode system. The result reveals that yttrium significantly promotes the overall corrosion resistance of AZ91D magnesium alloy by suppressing the cathodic reaction in corrosion process. However, the nucleation and propagation of corrosion pits on the surface of the 1.0wt.% Y modified AZ91D magnesium alloy indicate that pitting corrosion still emerges after the addition of yttrium. Furthermore, stress concentration caused by corrosion pits should be responsible for the drop of corrosion residual strength although the addition of yttrium remarkably weakens the effect of stress concentration at the tip of corrosion pits in loading process. [Copyright &y& Elsevier]

Abstract: The effect of corrosion on the tensile behaviour of the 1.0wt.% Ce modified AZ91 magnesium alloy was investigated by the immersion of the test bar in 3.5wt.% NaCl aqueous solution for 0, 12, 40, 108, 204, 372 and 468h with the subsequent tensile tests in this paper. The fractography was analyzed by scanning electron microscopy. The results show that pitting corrosion should be responsible for the drop of the corrosion residual strength within the testing time. The depth of the corrosion pits was statistically and quantitatively obtained by an optical microscopy and the maximal value was recorded as the extreme depth of the corrosion pit. Furthermore, the corrosion residual strength is linearly dependent on the extreme depth of the corrosion pit, which can be attributed to the loss of cross-sectional area and the emergence of stress concentration caused by the initiation and development of corrosion pits. [Copyright &y& Elsevier]

Abstract: Viscosities and densities of d-glucose–water mixtures were measured, and conductivities in the NiSO4–d-glucose–water system were also measured at 278.15–308.15K in 5K intervals. Based on the Lee–Wheaton conductivity equation, values of limiting molar conductivities Λ 0 and association constants K A were obtained. Changes in the standard thermodynamic functions, Gibbs energy enthalpy and entropy for a process of ion-pair formation were calculated at different temperatures. The results show that (1) at given temperatures, the Λ 0 values for 1/2NiSO4 decrease with increasing concentrations of d-glucose; (2) at fixed concentrations of d-glucose, the Λ 0 values for 1/2NiSO4 increase with increasing temperature; and (3) the process of association of NiSO4 is controlled by the change in entropy . [Copyright &y& Elsevier]

Abstract: Al2O3 and carbon short fibres reinforced AlSi12CuMgNi metal matrix hybrid composites were fabricated by preform squeeze-infiltrated route. The fibres distribution and microstructure of matrix in the hybrid composites were observed. Moreover, the effect of heat-treatment on the dry sliding friction and wear properties of the hybrid composites were determined by statistics method under the condition of 196N load and velocity of 0.837m/s. Alumina and carbon short fibres distributed hybrid uniformly in the hybrid composites. Metal matrix microstructure was fined after heat-treatment. The results of statistics analysis showed that four samples of wear rate and friction coefficient of both as-cast and as heat-treated hybrid composites accorded with normal distribution. The statistics average values of wear rate and friction coefficient of as-cast hybrid composites were larger than those of as heat-treated hybrid composites. Heat-treatment was beneficial to the improvement of dry sliding friction and wear property of the composites. Dominant wear mechanism of as-cast hybrid composites was ploughing grooves and delamination. Heat-treatment contributed to improving the resistivity of delamination of composites. Dominant wear mechanism of as heat-treated hybrid composites was slightly ploughing. [Copyright &y& Elsevier]

Shallow-buried rock mass/obstructions in a reclaimed sand site have seriously delayed a construction project in eastern Singapore, and seismic surveys were conducted to estimate the location and range of the rock. Active-source and passive-source seismic data were recorded using an array with 24 geophones at 1 m intervals. A 2D full waveform inversion (FWI) approach, multichannel analysis of surface waves (MASW), and cross-correlation seismic interferometry were used to process the collected seismic data. Results show that MASW and cross-correlation provide useful information, but limited to 1D S-wave velocity profiles and the upper surface of shallow buried rock. Using the full information of seismic waveform, the FWI approach can reflect even the range of rock. Sequential inversion with a low-pass frequency filter at incremental corner frequencies can increase the precision of the FWI approach. With higher precision, the FWI of surface waves is considered to be an attractive and effective method to detect underground obstruction. • FWI is used to process seismic data for underground obstruction survey. • An accurate 2D S-wave velocity structure can be acquired through FWI. • MASW can only reflect the upper surface of granite. • Accuracy of crosscorrelation appears lower than MASW and FWI at shallow depth. • Sequential application of low pass frequency filters can improve accuracy of FWI. [ABSTRACT FROM AUTHOR]

• SE of CNT composite grouts in inclined fracture with flowing water was investigated. • Inclination angle of fracture plays a crucial role in flowing water grouting. • CNT composite grouts are applicable for flowing water grouting in inclined fracture. • Silica fume improve SE of CNT composite grouts. A series of physical simulation tests were conducted to investigate performance of carbon nanotube (CNT) composite grouts in inclined fracture grouting with flowing water. The viscosity of grouts increases with an increase of CNTs content. Silica fume can improve the dispersion of CNTs and maximal fluid pressure of CNT composite grouts. Orthogonal experimental results shows that sealing efficiency (SE) of CNT composite grouts increases with an increase of CNTs and a decrease of initial flowing rate. Slight inclination can improve the SE of CNT composite grouts and superfluous silica fume has limited effects on SE. [ABSTRACT FROM AUTHOR]

Generally, the anti-seismic capacity of rural buildings in China is poor due to their irregular design and construction. On the basis of historical destructive earthquake records, corresponding earthquake loss evaluation compilations (1993–2016), field investigations, and remote sensing interpretation, building structures in rural Weinan are classified into two types and analyzed to acquire the seismic vulnerability matrices by employing the fitting method of beta probability density function (BPDF). Results show that BPDF can well reveal the probability density distribution of seismic damage index, and also the damage ratio obtained agrees well with the description of damage degrees in Chinese macroseismic intensity scale. The vulnerability indexes in rural areas of Yunnan, Sichuan, Qinghai provinces and in Weinan City (Shaanxi province) were calculated and a comparison of aseismic ability was made. Results show that, among the rural areas in Western China, the aseismic abilities of traditional buildings in rural Weinan are the lowest while those of masonry buildings are highest. Moreover, potential losses in rural Weinan are estimated on the assumption that a scenario earthquake with a magnitude Ms 6¾ hit Weinan City, proposed by the UK-China Collaboration programme "Increasing Resilience to Natural Hazards in Earthquake-Prone regions in China". It was found that the damage ratios obtained captured the distribution of the aseismic abilities of the rural buildings and therefore improved the accuracy of the loss assessment, which provides scientific basis for the scenario narratives. What we discovered in this paper is also helpful in future earthquake damage prediction and enhancement of public awareness on earthquake resistance. [ABSTRACT FROM AUTHOR]

Seismic vulnerability and hazard analyses play a significant role in comprehensive risk mitigation and seismic emergency planning, especially for the rural Weinan prefecture in northwestern China with a complex construction infrastructure and a high population density. Traditional methods assessing potential physical seismic damage prior to an earthquake are providing an incomplete picture for seismic risk assessments and post-disaster situations, and are insufficient for local authorities to plan mitigation strategies effectively. This study presents a novel perspective on scenario-based seismic vulnerability and hazard assessment. First, an in situ survey was carried out in three villages, Helan, Zhaojia, and Dongyu Village in the plain, loess, and mountain area respectively. Then, a quantitative analysis of building vulnerability and associated human homelessness under different seismic intensities was conducted based on the RISK-UE vulnerability index method. Finally, we estimated and analyzed other seismic impact scenarios. Results showed that the mean building vulnerability index is 0.69, 0.70, and 0.76 for Helan, Zhaojia, and Dongyu Village, respectively. Considering the possible displaced populations, Dongyu Village will have the highest proportion of homeless people. If an earthquake causes intensity greater than VII, Dongyu Village would suffer landslides and isolated-communication. The residents would have to rely on self-rescue and mutual rescue. These findings can be a potential guide to decision making in disaster risk reduction in rural Weinan. [ABSTRACT FROM AUTHOR]

It is known that nested states composed of ring-shaped hidden vorticity quantum droplets (QDs) with topological charges (S 2 = − S 1 , referred to as hidden vorticity) are stable in binary Bose-Einstein condensates (BECs). However, this nested multiring states with hidden vorticity are very extreme cases. Hence, the nested patterns with different topological charges are worth studying. In this paper, we use the imaginary-time-integration method to obtain for the first time the ring-shaped QDs with high topological charge (up to S 2 = 15) in a radially periodic potential. We analyzed in detail the influence of the modulation depth on the stability of the ring-shaped QDs. The trapping capacity of the troughs is studied with fixed modulation depth. Finally, we obtain the nested patterns constructed by ring-shaped QDs with different topological charges, greatly expanding the encoding of topological states. The results provide reference for designing data storage devices using vortex topology charges. • We have studied the ring-shaped QDs with arbitrary topological charges in a radially periodic potential. • We have analyzed stability intervals for the ring-shaped QDs, and studied the trapping capacity of the circular troughs. • We have obtained the stable nested vortex modes constructed by ring-shaped QDs with different topological charges. [ABSTRACT FROM AUTHOR]

Objective: We aimed to compare the prognosis of laryngeal squamous cell carcinoma (LSCC) and nSCCs of the larynx.Then we established a nomogram for nSCCs of the larynx.Methods: Prognosis between the 529 pairs nSCCs of the larynx patients and LSCC patients were compared after propensity score matching (PSM). 591 nSCCs of the larynx patients were divided into the modeling and validation groups. Univariate and multivariate Cox analyses obtain independent prognostic factors, which were then included in the nomogram to predict the 3 and 5 year survival. Prognostic accuracy of the nomogram was evaluated using the consistency index (C-index) and the calibration curve.Results: Prognosis of nSCCs of the larynx was poorer than LSCC. Age, race, tumor location, tumor-node-metastasis stage, and method were independent prognostic factors of nSCCs of the larynx (P < 0.05). Internal and external validation proves the nomogram reliable CONCLUSION: The nomogram showed good prognostic accuracy and would assist clinicians in making more accurate evaluations for patients. [ABSTRACT FROM AUTHOR]

Highlights: [•] Conductivities Λ for MnSO4–saccharide–water solutions were measured. [•] Limiting molar conductivity for ½MnSO4 decreases with increasing saccharide molality. [•] Values of Λ 0 for ½MnSO4 at a given m s are in the order: fructose>galactose>glucose. [•] Values of Λ 0 for ½MnSO4 at given m s are larger than those for ½MnSO4. [Copyright &y& Elsevier]

[Display omitted] • Species richness hotspots were identified by multi-species distribution modeling. • The magnitude and direction of future biodiversity hotspots changes were discussed. • The MaxEnt and InVEST models were complementary in biodiversity conservation. • Suggestions for biodiversity conservation were proposed based on gap analysis. Mainstreaming biodiversity into protection planning and management is of great significance for biodiversity conservation and sustainable development. Species potential distribution modeling is an effective way for species diversity evaluation and biodiversity hotspots identification, which are crucial for biodiversity conservation. Taking the Central Urban Area of Chongqing Municipality as the study area, the main objectives of this study were to identify the potentially suitable habitats, species richness and biodiversity of key protected species in current and future, determine the relative contribution of environmental factors and assess the conservation effectiveness of protected areas (PAs) based on MaxEnt model and gap analysis. The results showed that the current potentially suitable habitats of total key protected species were mainly located in "two rivers and four mountains", with a total area of 1610.55 km2, of which forestland accounted for 59.78 %. Species suitable habitats demonstrated clear topographic heterogeneity, and the distribution index decreased at first and then increased with increasing terrain niche index (TNI). Meanwhile, it was observed that key protected plants and birds shared similar suitable habitats in mountainous areas, with an overlapping area of 753.53 km2, and the high species richness covered 182.83 km2. In 2050, the future biodiversity hotspots would remain stable and increase steadily. In terms of the direction of centroid shift, the biodiversity hotspots would migrate to low latitude, low altitude and southeast by 8.34 km. The jackknife tests indicated that the potential distribution of key protected species was mainly determined by land use, mean diurnal range and TNI. Additionally, the problems of high protection gaps and low protection effectiveness coexisted in the existing PAs, with the overlapping area of the comprehensive biodiversity hotspots and the existing PAs was only 446.96 km2. Finally, suggestions for natural PAs system optimization and ecological protection were proposed. This study provides scientific supports for biodiversity conservation and efficient management. [ABSTRACT FROM AUTHOR]

The impact of polytetrafluoroethylene-nanoplastics (PTFE-NPs) on biological sewage disposal was delved, containing nitrogen remotion, microbiological activity and composition of extracellular polymer (EPS). The addition of PTFE-NPs reduced the removal efficiencies of chemical oxygen demand (COD) and ammonia nitrogen (NH 4 +-N) by 3.43 % and 2.35 %, respectively. In comparison with no PTFE-NPs, the specific oxygen uptake rate (SOUR), specific ammonia oxidation rate (SAOR), specific nitrite oxidation rate (SNOR) and specific nitrate reduction rate (SNRR) decreased by 65.26 %, 65.24 %, 41.77 % and 54.56 %, respectively. The PTFE-NPs inhibited the activities of nitrobacteria and denitrobacteria. It was worth noting that, nitrite oxidized bacterium was more resistant to adverse environments than ammonia oxidizing bacterium. Compared with no PTFE-NPs, the reactive oxygen species (ROS) content and lactate dehydrogenase (LDH) grew by 130 % and 50 % under PTFE-NPs pressure. The appearance of PTFE-NPs affected the normal function of microorganisms by inducing endocellular oxidative stress and destroying the completeness of the cytomembrane. The protein (PN) and polysaccharide (PS) levels in loosely bound EPS (LB-EPS) and tightly bound EPS (TB -EPS) increased by 4.96, 0.70, 3.07 and 0.71 mg g−1 VSS, under PTFE-NPs. Meanwhile, the PN/PS ratios of LB-EPS and TB -EPS increased from 6.18 and 6.41–11.04 and 9.29, respectively. The LB-EPS might provide sufficient binding sites for PTFE-NPs adsorption due to its loose and porous structure. The defense mechanism of bacteria against PTFE-NPs was mainly the PN in loosely bound EPS. Moreover, the functional groups referred to the complexation of EPS with PTFE-NPs were mainly related to N-H, C O, and C-N in proteins and O-H in polysaccharides. • The PTFE-NPs inhibited the activities of nitrobacteria and denitrobacteria. • The PTFE-NPs caused the ROS content and LDH release to increase. • The PN levels in LB-EPS and TB-EPS were higher than those of PS at PTFE-NPs pressure. • The main functional groups of EPS bound with PTFE-NPs were N-H, C O, C-N and O-H. [ABSTRACT FROM AUTHOR]

ZnO nanorods@nanoflowers (quantum dots) hybrid nanostructures have been successfully fabricated by the spin coating method. The transmission electron micrograph (TEM) and field-emission scanning electron microscopy (FE-SEM) images showed that ZnO quantum dots (QDs) and ZnO nanoflowers (NFs) had been assembled on the surfaces of ZnO nanorods (NRs) or in the upper parts of the gaps between the rods. The morphology of ZnO nanoflowers was formed through a general route of zero-dimensional (0D)→2D→3D, controlling by sodium dodecyl sulfate (SDS) during the experiment. The blue-shifts of Raman and PL spectra were observed for the hybrid nanostructures at room temperature, which were explained by the quantum confinement effects. Compared with the photocatalytic activities of the samples, ZnO NRs@NFs showed enhanced photocatalytic performance for the degradation of RhB under UV radiation, which could be attributed to the special structural feature with an open and porous nanostructured surface layer and the surface defects. ZnO NRs@NFs would show a wider application for its particular porous morphology. [ABSTRACT FROM AUTHOR]

[Display omitted] • PTFE-NPs weaken the Cu(II) and CIP antagonism on sludge activities. • Nitrifier was more alive to Cu(II) and CIP than denitrifier with or without PTFE-NPs. • Adsorption of CIP and Cu(II) by PTFE-NPs was synergistic. • PN level in EPS was decreased by PTFE-NPs at mixed Cu(II)/CIP. • PTFE-NPs abated the binding of functional groups in PN and PS to mixed Cu(II)/CIP. The work aimed to explore effects of polytetrafluoroethylene nanoplastics on joint inhibitions of ciprofloxacin and bivalent copper on the nitrogen removal in a sequencing batch reactor and its potential mechanisms. The addition of bivalent copper and/or ciprofloxacin reduced the ammonia nitrogen elimination rate with or without polytetrafluoroethylene nanoplastics. Adsorption kinetics and thermodynamics showed the binary bivalent copper and ciprofloxacin promoted their adsorptions by polytetrafluoroethylene nanoplastics. Polytetrafluoroethylene nanoplastics enhanced combined toxicities of ciprofloxacin and bivalent copper to sludge activities and microbial community involved into nitrification and denitrification due to the adsorption of ciprofloxacin and bivalent copper by polytetrafluoroethylene nanoplastics. With or without polytetrafluoroethylene nanoplastics, bivalent copper and/or ciprofloxacin caused more obvious level changes of protein than polysaccharide. This study provides novel insights for understanding the effect of combined heavy metals and antibiotics on the performance in a sequencing batch reactor with the nanoplastics stress. [ABSTRACT FROM AUTHOR]

• The time series reconstruction algorithm is applied to RSEI for the first time. • Corrected the correlation between RSEI and ecological components. • Alleviate the instability of RSEI time series. Remote Sensing Ecological Index (RSEI) is one of the most widely used ecological quality assessment indicators. Due to the noise caused by adverse atmoshperic conditions and other factors, the RSEI calculated from the original image usually has the phenomena of lack of information and unstable image quality. Therefore, based on Google Earth Engine (GEE) cloud platform, this study adopts three common data reconstruction algorithms firstly, namely: Savitory-Golay filter (SG), harmonic analysis of time series (HANTS), Whittaker Smoother (WS), which are used to reconstruct the original MODIS time series data in the Yangtze River Basin (YRB) from 2000 to 2020, in order to optimize the calculation process of RSEI. At the same time, three indicators (correlation coefficient (R), standard deviation (STD), root mean square error (RMSE)) are used for the accuracy evaluation. The results show that data reconstruction can fill gaps in RSEI, the reconstruction performance of WS and SG for four parameters is better than HANTS, and the four SG reconstructed sequences have the strongest correlation with the original sequences (R between 0.8 ∼ 1), while the WS reconstruction sequence has the lowest error value (both STD and RMSE are less than 1), both of them can correct the pixel value, which is conducive to maintaining the stability of RSEI in the temporal dimension; the RSEI produced by HANTS has the best accuracy, that is, R, STD, RMSE are respectively 0.898, 0.130, 0.104. As shown by the research, it is necessary to de-noise each parameter before synthesizing RSEI. This study can provide a theoretical basis for applying time-frequency algorithms to optimize the ecological monitoring performance of RSEI. [ABSTRACT FROM AUTHOR]

The Hahaigang W–Mo polymetallic skarn deposit is located in the central-eastern part of Gangdese tectono-magmatic belt in Lhasa terrane, Tibet. The deposit was discovered in 2007 with currently proven 46milliontons of WO3 ores, 12milliontons of Mo ores, and 1.31milliontons of combined Cu–Pb–Zn ores, at an average grade of 0.20% WO3, 0.07% Mo, 0.026% Cu, 0.49% Pb, and 3.1% Zn. Ore bodies occur in veins or disseminations, and are confined within the NE-striking Dalong fault zone which is hosted by the Lower-Permian Pangna Group of dominantly quartz sandstone and slate. Several granitic plutons are exposed in the area or known from drill-holes. Ages of these granitic plutons are determined by using zircon U–Pb LA–ICP–MS method. For example, the biotite monzogranite yields a 206Pb/238U–207Pb/238U concordia age of 58.66±0.90Ma and a weighted mean 206Pb/238U age of 57.02±0.42Ma. The granite porphyry yields a 206Pb/238U–207Pb/238U concordia age of 109.1±8.9Ma and a weighted mean 206Pb/238U age of 114.0±2.6Ma. The biotite monzogranite yields a weighted mean 206Pb/238U age of 56.1±1.1Ma. Re–Os isochron age of 63.2±3.2Ma from 5 molybdenite samples collected from the W–Mo skarn ores is also obtained in this study. The zircon U–Pb and molybdenite Re–Os geochronological data suggest that the W–Mo mineralization was not temporally associated with any of the dated igneous plutons. However, the molybdenite Re–Os age of 63.2±3.2Ma indicates that the W–Mo mineralization might have occurred during the main India–Eurasia collision that was initiated around 65Ma. Microprobe analysis of ilvaite that occurs in two generations in the W–Mo skarn ores reveals a close relationship to Ca–Fe–F-rich hydrothermal fluids, which were probably derived from deeply-seated magmas. We suggest that ascent of the fluids was strictly controlled by the ore-controlling Dalong fault zone, and that chemical interaction and metasomatism between the fluids and the Lower-Permian Pangna quartz-feldspathic host rocks produced the ilvaite and the W–Mo polymetallic skarn deposit during the main India–Eurasia collision. Although the majority of the polymetallic deposits in the Gangdese belt are reported to be either pre- or post-main collision, it is evident from this study that the main collision also produced W–Mo polymetallic mineralization within the belt. [ABSTRACT FROM AUTHOR]

Abstract: ZA22 foams with open-cell structure were fabricated by replication process using NaCl preform. These foams have the equivalent cell size to salt particle (840–3900μm in size). The compressive property and energy absorption characteristic of ZA22 foams were investigated. ZA22 foams show the deformation characteristics of plastic foams. The relation between the relative plastic collapse stress and relative density can be described with Gibson and Ashby’s model. The energy absorption capacity of the foams gradually increases for given relative density from 0.279 to 0.396, whereas, the energy absorption efficiency is independent of the relative density. [Copyright &y& Elsevier]

• The RSEI of the long time series is calculated by GEE. • Apply Theil-Sen-MK trend analysis to judge the long-term trend of RSEI. • Investigate the contribution of environment, human, and topography to RSEI changes. The Yangtze River Basin has a wide range and complicated topography. In recent years, under the background of climate and land cover change, the ecological response of the whole ecological quality of the Yangtze River Basin is still unknown. To reveal the spatiotemporal changes in ecological quality in the Yangtze River Basin from 2001 to 2019 and their relationship with environmental and topographical factors, this study used the Google Earth Engine (GEE) platform to calculate the remote sensing ecological index (RSEI) based on the Moderate-resolution Imaging Spectroradiometer (MODIS) product image set, combined with the digital elevation data set and statistical yearbook. The data evaluated the ecological quality of the Yangtze River Basin and analyzed its causes. The results showed that: 1) the average RSEI of the Yangtze River Basin showed an overall upward trend, the growth rate was 0.027 (year−1), and the variation ranged from 0.5 to 0.568. The overall ecological quality rank was mainly neutral and slightly good. 2) The ecological quality of 85.7% of the Yangtze River Basin remains stable. A total of 11.2% of the regional ecological quality is improving, and 3.1% of the regional ecological quality is declining. Areas with reduced ecological quality are concentrated in the Hengduan Mountains. The dominant LST factor drives the deterioration of its ecological quality at a rate of −1.06 (year−1). The areas with improved ecological quality are concentrated in the upper and middle reaches of the Yangtze River. The dominant WET factor drives its ecological quality to improve at a rate of 0.27 (year−1). 3) From the perspective of topography, the ecological quality of the Yangtze River basin shows a wave-like decline and first rises and then falls in elevation and slope (the elevation is bounded by 2000 m and 6000 m, and the slope is bounded by 15°.). The average RSEI of the Yangtze River Basin is the highest on the northwest slope (0.554), and the ecological quality of sunny slopes is generally higher than that of shady slopes. The research shows that from 2001 to 2019, the overall ecological quality of the Yangtze River Basin has improved and evolved, but the ecological quality of the Hengduan Mountains has declined. Therefore, implementing different ecological protection policies in different regions is an important strategy for enhancing the stability of the ecosystem. [ABSTRACT FROM AUTHOR]

Abstract: The 13C NMR spectra of methyl β-d-glucopyranoside, methyl β-d-galactopyranoside, methyl β-d-xylopyranoside, and methyl β-l-arabinopyranoside were recorded in CaCl2/KCl+D2O mixtures and in D2O. The chemical shifts of C-1, C-3, and C-5 in the methyl β-d-glucopyranoside and methyl β-d-galactopyranoside decrease rapidly as molalities of CaCl2/KCl increase, while those of C-1, C-2, and C-3 in the methyl β-d-xylopyranoside and methyl β-l-arabinopyranoside decrease rapidly as molalities of CaCl2/KCl increase. Cations (Ca2+/K+) can weakly complex with O in OMe of the pyranosides studied. Results are discussed in terms of the stereochemistry of the pyranoside molecules and the structural properties of the ions. [Copyright &y& Elsevier]

Abstract: The closed-cell Zn-22Al composite foams reinforced by 3 vol.% Al2O3 short fibers were fabricated with melt foaming method using CaCO3 as blowing agent. The distributions of the short fibers in the composite foams were observed by scanning electron microscopy (SEM) and the compressive properties of the composite foams were investigated in quasi-static condition. The compression test indicated that Zn–22Al/Al2O3 composite foams show better compressive properties than Zn–22Al alloy foams. The compressive curves of the composite foams exhibit a smooth and no dentate collapse plateau region; the compressive yield stress and energy absorption capacity of the composite foams increase more rapidly than those of Zn–22Al alloy foams with increasing density. [Copyright &y& Elsevier]

Abstract: The closed-cell Zn-22Al (ZA22) foams were fabricated by the melt foaming process using CaCO3 blowing agent. The compressive properties of ZA22 foams were investigated under quasi-static condition. The results show that the compressive stress–strain curves of ZA22 foams exhibit three distinct deformation regions: a linear elastic region where the stress rises linearly with increasing strain; a plastic plateau region with slight stress fluctuation over a wide range of the strain; and a densification region where the stress increases rapidly. The plastic collapse stress of ZA22 foams rises with increasing relative density. The relationship between relative plastic collapse stress and relative density is in accordance with Gibson and Ashby model. [Copyright &y& Elsevier]