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The promotion of cellulose-based paper straws is one of the important ways to improve white pollution nowadays. However, developing composite straws that are simultaneously highly biocompatible, safe, and non-toxic and that overcome the low water stability and physical strength problems caused by the inherent hydrophilicity of the raw material cellulose has become an important challenge in the development process. In this study, a new all-natural superhydrophobic straw (CFS) made of a composite of cellulose nanofibers and stearic acid was introduced. Stearic acid is a saturated fatty acid derived from plant and animal oils. Inspired by the specific hydrophobicity of sugarcane cane peel, a green straw with both superhydrophobicity (water contact angle up to 153°) and remarkable mechanical strength (tensile strength up to 67.15 MPa) was developed by controlling the hydrophobic modification conditions of stearic acid through solvent vaporization. Furthermore, the composite straws under wet conditions had lower water absorption and exhibited excellent wet tensile strength compared to commercial paper straws. In addition, the composite straw without the addition of chemical binders avoids the defects of non-renewable products, fits into the global green development concept, and brings new strategies for the development of cellulose-based materials. [Display omitted] • Superhydrophobic CFS straws inspired by sugarcane epidermis. • CFS straws exhibited remarkable mechanical strength. • CFS straws showed the property of being easily recycled and reused. • CFS straws presented new options for plastic products. [ABSTRACT FROM AUTHOR]

[Display omitted] • Phosphorylated porous phenolic resins (PO-PPRs) were prepared with POCl 3 post-modification. • PO-PPRs with hierarchical pore structures demonstrated a broad pH working range (3.0–7.0). • PO-PPRs exhibited excellent adsorption capacities of light and heavy REEs (63.9–118 mg/g). • The Nd3+/Al3+ separation factor of PO-PPR-1 reached 24. • PO-PPRs can efficiently extract and recycle low-concentration REEs from tailing wastewater. Efficient extraction and recycling of rare earth elements (REEs) from low-concentration complex tailing wastewater is critical to meeting the growing industrial demands and optimizing resource utilization. In this work, three phosphorylated porous phenolic resins (PO-PPRs) were prepared via the phosphorylation of phenolic hydroxyl groups with POCl 3 , and employed to extract REE3+ from both simulated and practical low-concentration REE3+-containing aqueous solution. The PO-PPRs, characterized by hierarchical pore structures, exhibit high adsorption capacities for both light and heavy REE3+ ions over a broad pH working range from 3.0 to 7.0, along with fast adsorption kinetics (<30 min). And the maximum adsorption capacities of PO-PPRs for Nd3+, Dy3+ and Y3+ were found to be 104.1, 118.0 and 63.9 mg/g, respectively. Furthermore, the introduction of phosphonic groups significantly improves the REE3+ adsorption selectivity against various interfering metal ions such as Na+, K+, Ca2+, Mg2+, and Al3+. For instance, the Nd3+/Al3+ separation factor (S.F.) of 24 exceeded that of most commercial resins and reported materials. In a simulated mixed multi-element aqueous solution system containing Nd3+, Dy3+, Y3+, Al3+, Ca2+, Mg2+, Mn2+, K+ and Na+, PO-PPR-1 extracted 82.5% of total REE3+ while maintaining Al3+ adsorption efficiency of less than 13%. Moreover, the extraction efficiency of total REE3+ for PO-PPR-1 in pretreated practical wastewater from ion-adsorbed ores tailing reached 99.6%. Additionally, PO-PPRs demonstrated easy regeneration and excellent recycling performance after 5 consecutive adsorption–desorption cycles, confirming their promising application potential in low-concentration REEs extraction. [ABSTRACT FROM AUTHOR]

Abstract Determination of the fatty acid profile of milk fat generally involves a protocol that comprises total lipid extraction, transesterification and GC analysis. The lipid extraction step is time-consuming and often employs toxic solvents such as chloroform. A novel protocol is presented here that skips the lipid extraction step and allows the determination of fatty acid composition via direct methylation of milk fat isolated after centrifugation of raw milk. This new method is reliable for relative quantification of fatty acids in raw milk fat and offers a much higher throughput compared with the classical methods. [ABSTRACT FROM AUTHOR]

Abstract Novel binuclear platinum complex (FPT) 2 Pt 2 (diPic) and mononuclear platinum complex (FPT)Pt(Pic) were designed and synthesized, where FPT is N-(4-(6-(9,9-diethyl-9H-fluoren-2-yl)pyridin-3-yl)phenyl) N-phenylbenzenamine, diPic is 3-(6-(2-carboxypyridin-3-yloxy)hexyloxy)picolinic acid, and Pic is picolinic acid. The photophysical, electrochemical and thermal properties, as well as electroluminescent (EL) properties for both platinum(II) complexes were studied. Compared to (FPT)Pt(Pic), (FPT) 2 Pt 2 (diPic) exhibited stronger phosphorescent emission in PL spectra and higher Φ PL , owing to the enhanced spin-orbit interaction of platinum centers. Moreover, the monochromatic devices based on (FPT) 2 Pt 2 (diPic) showed better EL properties than (FPT)Pt(Pic). Based on that, the single-emissive-layer WPLEDs using (FPT) 2 Pt 2 (diPic) as orange emitter and FIrpic as blue emitter were also obtained. The WPLEDs show best performances with a maximal LE of 1.3 cd/A, and a CIE coordinates of (0.35, 0.37) which is very close to the pure white emission. Work is still underway to improve the device efficiency and color purity of these iridium and platinum complexes co-doped WPLEDs. Graphical abstract A novel binuclear platinum complex (FPT) 2 Pt 2 (diPic) is designed and synthesized. Both orange and white PLEDs are fabricated with a simple single-emission-layer configuration based on (FPT) 2 Pt 2 (diPic). The WPLEDs combination of (FPT) 2 Pt 2 (diPic) with FIrPic exhibit a CIE coordinates of (0.35, 0.37), which is very close to the pure white color. Image 1 Highlights • Novel binuclear platinum complex and mononuclear platinum complex were synthesized. • Photophysical, electrochemical and thermal properties of Pt complexes were studied. • (FPT) 2 Pt 2 (diPic) exhibited stronger phosphorescent emission and higher Φ PL. • The monochromatic devices based on (FPT) 2 Pt 2 (diPic) show better EL property. • The single-emissive-layer WPLEDs based on (FPT) 2 Pt 2 (diPic) and FIrpic were achieved. [ABSTRACT FROM AUTHOR]

Three acid- and alkaline-catalysed transesterification methods were compared with the aim to validate a simple yet reliable protocol for fatty acid (FA) profiling of milk fat. While both the acid- and alkaline-catalysed methods were able to convert completely triglycerides and phospholipids into fatty acid methyl esters (FAMEs), the acid catalyst caused significant degradation of conjugated linoleic acid C18:2c9t11 at high temperature. Although a milder temperature can mitigate this negative impact, a long reaction time (2 h) is required to achieve full methylation. By contrast, despite being unable to methylate free fatty acids (FFA), the alkaline-catalysed transesterification yielded comparable results for all major FA due to the very low level of FFA in milk. The alkaline-catalysed methylation is benign for C18:2c9t11. We recommend here a simple one-step protocol based on 0.2 M methanolic KOH, a short reaction time (20 min) and a mild reaction temperature (50 °C) for milk FAME preparation. [ABSTRACT FROM AUTHOR]

Bovine milk contains 3–5% of fat, of which the dominant portion (about 98%) is in the form of triacylglycerols, whereas polar lipids such as glycerophospholipids and sphingolipids are minor components (0.5–1%) of milk fat. Milk fat is thought to contain several thousand lipid species, making it the most complex material in nature in terms of lipid composition. Significant progress has been made in the past two decades in the identification and quantification of lipid species of milk thanks to the advance in analytical tools especially high-resolution mass spectrometers (MS). Currently, milk lipids are characterized mainly in two ways, i.e. global fatty acid composition profiling by gas chromatography and lipid molecular species identification and quantification by liquid chromatography tandem MS; the former provides information related to the physicochemical properties and nutritive quality of milk fat, whereas the latter provides the detailed chemical structure of lipid species. Until now, only about 400 lipid species have been described in bovine milk, with many low-abundance species remaining to be discovered. The merits and limitations of various separation techniques and different MS methodologies applied to lipid structural elucidation and quantification are critically reviewed and the challenging problems to be solved in milk lipidomic analysis highlighted. [ABSTRACT FROM AUTHOR]

The aquatic plant Azolla became increasingly popular as bioenergy feedstock because of its high growth rate, production of biomass with high levels of biofuel-producing molecules and ability to grow on marginal lands. In this study, we analysed the contribution of all organs of Azolla to the total yield of lipids at vegetative and reproductive stages and in response to stress. Triacylglycerol-containing lipid droplets were detected in all (vegetative and reproductive) organs with the highest level in the male microsporocarps and microspores. As a result, significantly higher total yields of lipids were detected in Azolla filiculoides and Azolla pinnata at the reproductive stage. Starving changed the yield and composition of the fatty acid as a result of re-direction of carbon flow from fatty acid to anthocyanin pathways. The composition of lipids, in regard the length and degree of unsaturation of fatty acids, in Azolla meets most of the important requirements for biodiesel standards. The ability of Azolla to grow on wastewaters, along with their high productivity rate, makes it an attractive feedstock for the production of biofuels. [ABSTRACT FROM AUTHOR]

Seasonal change of milk composition could offer opportunities for dairy manufacturers. A systematic survey on seasonal variation of six classes of polar lipids was conducted with 19 Holstein cows over the entire milking season using liquid chromatography-mass spectrometry technique. This study revealed that most polar lipid classes were positively correlated with the total fat content, but negatively correlated with fat globule size. All polar lipid classes displayed a large cow-to-cow variation as well as seasonal variation. All of the six classes showed a gradual increase over the milking season with the highest concentration observed in May (autumn). However, the proportion of different polar lipid classes remained constant during the entire milking season. This finding suggests that the production of polar lipids is highly regulated in the mammary gland. The implication of such a seasonal variation of polar lipids in the nutritional and technological aspects of milk is discussed. [ABSTRACT FROM AUTHOR]

In this study, we successfully prepared fly ash-based SiO 2 -Al 2 O 3 microspheres using phase separation followed by acid leaching. Thermal analysis and X-ray diffraction were used to identify the optimal temperature range of heat treatment. The chemical composition and surface property of the microspheres were analyzed using X-ray fluorescence and contact angle measurements, and scanning electron microscopy was used to characterize the appearance of the microspheres. The results showed that the SiO 2 -Al 2 O 3 microspheres were composed of 60–80 wt% SiO 2 and 10–12 wt% Al 2 O 3 with a uniform particle size, a hydrophilic surface, and high alkali resistance. Heat treatment studies revealed that the phase separation temperature should not exceed 900 °C to avoid crystallization. The mean particle size of the SiO 2 -Al 2 O 3 microspheres decreased with an increase in the heat treatment temperature. Additionally, observing the evolution of the phase structure at 800 °C showed that there was fusion between the SiO 2 -Al 2 O 3 -enriched phases via interfacial tension in the later stage, resulting in larger spherical phase structures. Further, an increase in the Al 2 O 3 , Fe 2 O 3 , and CaO composition decreased the SiO 2 -Al 2 O 3 microspheres particle size, and therefore inhibited phase separation. [Display omitted] [ABSTRACT FROM AUTHOR]

Using LC-LTQ-Orbitrap MS we were able to identify 10 major phosphatidylinositol (PI) species present in 32 infant formulas (IF) collected from Australia, Europe and the USA. Based on the species fingerprint, the 32 formulas can be classified into several distinct groups by PCA analysis; this grouping pattern reflects origin and the label information of the formulas. The total content of all PI species was determined by LC-Triple Quadrupole MS in negative MRM mode using external standard calibration. The content of PI showed large variation between formulas and was very high in certain cases, which is believed to be related to the use of soybean lecithin in these products. Our study indicates that the content and speciation of PIs have significant contribution to the total amount of inositol in all 32 products surveyed; this contribution may be important for the fine nutritional profile and biological functions of IF products. [ABSTRACT FROM AUTHOR]

For LC–MS-based lipidomic analysis of milk, total lipid extraction from raw milk is generally conducted with Folch or Bligh and Dyer methods; both methods are based on two-phase partition of lipids, and thus time-consuming. In this work, three solvent systems for one-phase extraction of milk lipids were compared with the standard Folch method. Two of the solvent systems (butanol/methanol, 3:1 and 1:1) previously tested for lipid extraction from plasma were found to provide adequate extraction for polar lipids, but incomplete extraction for triglycerides, especially highly lipophilic species. By contrast, our newly designed solvent mix composed of butanol, methanol and chloroform (at a 3:5:4 ratio) provided similar extraction efficiency for triglycerides and higher yield for some of the phospholipids, as compared to the Folch method. This new one-phase extraction method is very simple yet comprehensive and thus suitable for high throughput lipid analysis of milk samples. [ABSTRACT FROM AUTHOR]

Polar lipids (PLs) are a significant functional component of milk that are difficult to quantitate. A simple method for comprehensive identification and quantitative analysis of all essential PL species using bovine milk is described. The lipid fraction was extracted by a mix of chloroform and methanol and the extract was directly used for PL identification and quantification. PLs were separated by hydrophilic interaction liquid chromatography (HILIC) and detected by an Orbitrap mass analyser in positive mode. The structure of PLs was established or confirmed by tandem MS in both positive and negative modes. The method is sensitive (with a LOD for all PL classes ≤0.1 ng) and reproducible, enabling simultaneous quantification of 70 PL species within a run of 45 min. Application of this method to the quantification of PLs in 32 bovine milk samples revealed the relative abundance of different PL classes, significant variation of PL content between individual samples and the correlation between the major PL classes. The method provides a tool for investigating the variation and metabolism of important PL components in bovine and human milk and in diverse mammalian species. [ABSTRACT FROM AUTHOR]

• First adoption of Paterno-Buchi reaction in studying milk lipid fine structure. • Unsaturated fatty acids show a non-specific regio-distribution in phospholipids. • Regioisomers are widespread in milk phospholipid species. • Double-bond isomers of C18:1 and C18:2 are widely detected in milk phospholipids. Hundreds of phospholipid (PL) species with defined fatty acid (FA) composition have been identified previously in bovine milk using liquid chromatography tandem mass spectrometry (LC-MS/MS). Paterno-Buchi photochemical reaction coupled with LC-MS/MS was applied in this study to further unravel the regio-distribution and double bond (DB) locations of FAs. Using SPE-purified PLs and 2-acetylpyridine as the photochemical derivatization reagent, we were able to reveal the non-specific regio-distribution of unsaturated FAs and the widespread occurrence of regioisomers in milk PLs. Although Δ9 and Δ9,12 were found to be the predominant DB location(s) for C18:1 and C18:2 respectively, other DB positional isomers such as C18:1Δ11, C18:1Δ12 and C18:1Δ13 and C18:2Δ9,11 were widely detected in PL structures, implying that the minor isomers of C18:1 and C18:2 equally participate in the synthesis of PLs. Our study provides novel information on the fine structure of milk PLs and further underlines the complexity of milk lipid composition. [ABSTRACT FROM AUTHOR]

Abstract: Current liquid chromatography (LC) based methods for the analysis of polar plant metabolites require multiple runs using complex mobile phases and a combination of different columns. Here we describe a fast liquid chromatography–mass spectrometry (LC–MS) method for the determination of major polar metabolites in plants that requires only a single run using a single column. The method takes advantage of the ability to acquire both positive and negative data in an ion trap mass spectrometer (MS) and also the accurate mass capability of the orbitrap MS. The separation of polar compounds is achieved with a polar, reversed-phase column (Synergi Hydro-RP). A single analysis with a 25min runtime is able to reliably determine the level of nearly all essential amino acids, several major organic acids and several major sugars in plant materials, as exemplified by analysis of a perennial ryegrass extract. The level of detection on column was below 0.1ng (average 0.03ng) for most amino acids, below 5ng (average 2.3ng) for organics acids and below 1ng (average 0.64ng) for sugars. The levels of quantified metabolites in ryegrass varied from 22μg/g dry weight for histidine to 41mg/g dry weight for sucrose. [Copyright &y& Elsevier]

Surfactants are almost always present in herbicide treatment solutions with the aim to improve spray droplet retention on and penetration of active ingredients (a.i.s) into plant foliage. The effects of surfactants on the foliar uptake of herbicides are complex and only partially understood. The influence of a range of non-ionic polyoxyethylene surfactants on the uptake of two herbicides, glyphosate and 2,4-dichlorophenoxyacetic acid (2,4-D), was compared using three plant species, wheat, broad bean and common lambsquarters. Surfactants of higher ethylene oxide (EO) content provided greater uptake enhancement for glyphosate, whereas those of lower EO content were more beneficial for 2,4-D uptake. Among surfactants of the same EO content, those containing a C13/C15 linear alkane hydrophobe moiety appeared to be more efficient for promoting the uptake of both herbicides. When a suitable surfactant was used, glyphosate uptake into both bean and wheat foliage increased steadily with increasing surfactant concentration and reached a maximum at 0.5%. In the presence of a constant surfactant, higher percentage uptake of herbicide was obtained with higher a.i. concentrations for glyphosate, but with lower a.i. concentrations in the case of 2,4-D. In the presence of an organosilicone surfactant, the stomatal uptake of glyphosate varied with both surfactant concentration and plant species. The effect of non-silicone surfactants on the cuticular uptake of glyphosate also varied with plant species. It can be concluded that the effects of surfactants on foliar uptake of herbicides depend not only on their chemical structures (hydrophobe and hydrophile moieties) and concentration, but also on the physicochemical properties and concentration of a.i.s and the leaf surface character of the plant species. [Copyright &y& Elsevier]

Several novel green-emitting iridium dendrimers has been successfully designed and synthesized with carbazole as the dendron, which is covalently attached to the emissive bis[2-(2-dibenzothienyl)pyridine]picolate iridium(III) [(DBTPy) 2 Irpic] core through a nonconjugated link to form an efficient self-host system for nondoped electrophosphorescent device applications. All the iridium dendrimers display green emission, possess good thermal stability and high photoluminescence quantum yields. As well as, non-doped solution-processed OLEDs were successfully fabricated based on the resulting Ir-1, Ir-2 and Ir-3 as green-emitting phosphors. By increasing the density of carbazole dendrons at the edge of the emissive core, luminescence self-quenching caused by the intermolecular interactions in the solid state can be significantly reduced. Therefore, the OLEDs based on Ir-3 show the best performances with a maximal luminous efficiency of 0.24 cd/A and a maximum brightness of 2520 cd/m2. This work will shed light on the development of novel self-host phosphorescent iridium dendrimers for solution processable nondoped electrophosphorescent devices. Novel green-emitting iridium dendrimers with carbazole as the dendron and bis[2-(2-dibenzothienyl)pyridine]picolate iridium(III) as core through a nonconjugated link have been successfully designed and synthesized to form an efficient self-host system for nondoped electrophosphorescent device applications. Image 1 • Three novel green-emitting iridium dendrimers has been successfully synthesized. • The iridium dendrimers use carbazole as dendron and (DBTPy) 2 Irpic as core. • Nondoped solution-processed OLEDs were fabricated with these iridium dendrimers. • By increasing the density of carbazole dendrons, self-quenching can be reduced. [ABSTRACT FROM AUTHOR]

• Two new methods for fatty acid methylation without lipid extraction were validated. • Dried milk can be reliably used for in situ alkali-catalysed transesterification. • Acidic methylation of fresh milk is feasible with optimised reaction parameters. • The new methods are applicable to both homogenised and raw milk samples. Determination of the fatty acid (FA) profile of milk fat generally involves total lipid extraction from liquid milk, transesterification and GC analysis. The lipid extraction step is time consuming and often employs toxic solvents such as chloroform. Two alternative methods are presented here that skip the lipid extraction step and allow the determination of FA composition via direct transesterification of dried milk and liquid milk respectively. We have shown that dried milk can be used directly in alkaline-catalysed methylation, whereas direct transesterification of both dried milk and fresh milk is feasible with acidic methanol. Both methods generate similar results as compared to the classical two-step method (i.e. lipid extraction and FA methylation) when optimised methylation parameters (temperature, time, milk and reagent volume) are followed. By omitting the lipid extraction step, these simplified one-step methods offer a much higher throughput and a reduced cost in FA composition analysis of milk samples. [ABSTRACT FROM AUTHOR]

• Large-scale shaking table tests were carried out for a subway station structure. • The isolation mechanism of Mini-NRB installed in the structure were studied. • Real-time monitoring of structure deformation was realized. • Mini-NRB reduces the bending moment of column by 60%–80% and shear force by 90%. A series of shaking-table tests of a subway station structure with mini natural rubber bearings (Mini-NRBs) installed at column ends were carried out for near-field earthquake motions. By comparing the dynamic response of the structure model with or without Mini-NRB, the isolation mechanism and effectiveness of Mini-NRB on the station model were studied. It is found that the Mini-NRB has an obvious isolation effect on the column of the structure. After installing Mini-NRB, the lateral stiffness of the column decreases greatly, which reduces the bending moment and shear force at the column end by 60%–80% and about 90% respectively under near-field earthquake excitation. The test data, real-time monitoring pictures, and ultimate structural seismic damage all show that Mini-NRB shares most of the lateral deformation of the column, so that the column is no longer a vulnerable spot of the subway station structure. In addition, Mini-NRB reduces the high frequency component of the middle plate response, thus reducing the peak acceleration response of the middle plate by 3%–10%. However, the lateral deformation of the structure and the internal force of the sidewall will increase. The lateral deformation of the structure with Mini-NRB increases by 30%–50% and the bending moment at the end of the side wall increases by 5%–25%. [ABSTRACT FROM AUTHOR]

The practice of crime risk mapping, enabled by the utilization of geospatial big data such as street view images, has received significant research attention. However, in situations where available data is scarce, mapping models may suffer from underfitting and generate inaccurate spatial pattern estimations of crime risk. The covert nature of pickpocketing crimes results in limited observed areas relevant to such criminal events, leading to insufficient coverage of geospatial data. Moreover, the location of crime is also influenced by socio-economic characteristics that may introduce biases into crime risk estimates. These factors render it challenging for the model to capture a valid crime risk pattern, potentially yielding misleading conclusions. Therefore, effectively extracting crime risk with limited data remains a challenge, especially when relying on easily accessible, widespread, and unbiased geospatial data. To address this challenge, we propose a novel crime risk assessment framework based on deep anomaly detection techniques, assuming that urban landscape anomalies carry deep crime risk information. We take Shenzhen as the study area and map the distribution of pickpocketing risk using street view images, accurately revealing the spatial aggregation of pickpocketing crime risk. Our findings indicate that pickpocketing crime in China is caused by regional economic conditions, built environment factors, and human routine activities. This study provides valuable insights for policing and prevention strategies aimed at addressing pickpocketing crimes in large Chinese cities. By leveraging our proposed crime risk assessment framework, decision-makers can allocate resources more efficiently and develop targeted interventions to mitigate crime risks. • A deep learning-based model for mining pickpocketing crimes from street view images is proposed. • With the idea of anomaly detection, crime risk information can be extracted from a small number of street view images with crime labels. • The reliable parcel-level pickpocketing risk distribution was mapped in China's megacity. • Pickpocketing crime in China is multifactorial and spatially heterogeneous. • Pickpocketing crime risk is aggregated and affected by neighbourhood socioeconomic conditions and the built environment. [ABSTRACT FROM AUTHOR]

• A new seismic barrier for underground structures is proposed to control the Rayleigh waves. • The soil acceleration response is reduced within the frequency range of 0.5–5 Hz. • The maximum layer drift of the subway station is reduced by over 40 %. • The internal forces of structural components are reduced by 70 % on average. • A novel index is proposed to evaluate the performance of seismic barriers. This research introduces a novel seismic mitigation approach for civil engineering constructions, utilizing seismic metamaterials, and particularly studies its application to underground structures. This approach involves the implementation of a regional seismic barrier, designed in the form of piles periodically clamped to a concrete foundation. The efficacy of this seismic barrier is explored through comprehensive numerical simulations. A wave propagation study is conducted to investigate the attenuation efficiency for Rayleigh waves in the frequency domain. Besides, dynamic analysis is performed on a two-layer and three-span subway station subjected to actual seismic recordings. The results from the wave propagation study reveal a notable reduction in acceleration response within the frequency range of 0.5 Hz–5 Hz when employing the seismic barrier, in contrast to the free-field scenario. Dynamic analysis demonstrates that the implementation of the proposed seismic barrier leads to a significant decrease in both the maximum layer drift and the structural internal forces of the subway station. Moreover, the relative displacement of soil proves to be a pertinent metric for evaluating the seismic control efficacy of the proposed barrier for underground structures. [ABSTRACT FROM AUTHOR]

• A lightweight nonlinear response prediction model is established based on 1D-CNN. • The performance of 1D-CNN is excellent. • The randomness of ground motions and soil parameters are considered simultaneously. • The calculation cost of stochastic seismic response has been significantly reduced. • A comprehensive stochastic dynamic analysis is conducted using PDEM. The randomness of ground motions and soil properties has a significant impact on the seismic response of underground structures. The probability density evolution method (PDEM) is a powerful stochastic dynamic analysis method. By decoupling the physical space and probability space, any number of random excitation variables can be incorporated into the dynamic system, thereby accurately capturing the time-varying evolution of structural dynamic response. However, due to the expensive computational cost of nonlinear time history analysis (NLTHA) of underground structures, the application of the PDEM that requires many calculation samples is severely limited. In view of this, this paper proposes a lightweight stochastic seismic response analysis method for the subway station structure based on deep learning and PDEM. Firstly, mathematical models of stochastic ground motions and random soil shear wave velocity profiles are constructed. Two types of random excitations are coupled using the high-dimensional space optimization point selection method. The one-dimensional convolutional neural network (1D-CNN) is used as a proxy model to map the free field's nonlinear time-history response to the subway station structure's nonlinear time-history response. The computational cost of stochastic dynamics analysis has been significantly reduced. Subsequently, the predicted results are combined with PDEM to conduct a comprehensive analysis and evaluation of the subway station structure's seismic response and seismic performance. The research results indicate that the proposed 1D-CNN model has superior predictive performance, with a computational cost of approximately 92.5% less than the traditional process. The evolution of the subway station structure's inter-storey drift ratio (IDR) is mainly influenced by stochastic ground motions. However, under the combined random excitation, the peak value of IDR is larger and its occurrence time is earlier, so the establishment of earthquake evacuation plans should refer to this working condition. Both the randomness of soil properties and the randomness of ground motions need to be considered, otherwise, underground structures' seismic performance will be overestimated. This study provides new technologies and directions for seismic analysis and design of underground structures. [ABSTRACT FROM AUTHOR]

[Display omitted] • 2D multilayered Ti 3 C 2 T x MXene adsorbents were fabricated via selective Al element etching. • Li+-intercalation increased the interlayer spacing and surface area. • TCF-2 exhibited broad working pH range and excellent Nd3+ adsorption capacity (517.8 mg/g). • The Nd3+/Fe3+ selectivity of TCF-2 reached 221. • The adsorption mechanism was elucidated using different characterizations. Recovering rare earth elements (REEs) from low-concentration REE-bearing waste streams has been deemed as a sustainable approach to diversity REE supply and reduce environmental burden. However, highly selective separation of trivalent Fe3+ and Al3+ impurities during low-concentration REE processing still remains a critical challenge. In this study, two-dimensional multilayered MXene adsorbents TCFs were successfully prepared and utilized for Nd3+ adsorption via selective etching of Al element in Ti 3 AlC 2. It was found that LiF/HCl-etched TCF-2 can simultaneously realize effective Al etching, interlayer spacing expansion and in-situ Li+ intercalation. The intercalated Li+ amount was up to 4.44 wt% (6.40 mmol/g). Compared with HF-etched TCF-1, TCF-2 demonstrated boosted adsorption kinetics (2 h), large adsorption capacity (517.79 mg/g), impressively high selectivity (Nd3+/Fe3+ SF = 221, Nd3+/Ca2+ SF = 858, Nd3+/Mg2+ SF = 3545), and broad working pH range (2–7). Various experimental characterizations reveal that selective Nd3+ recovery is owing to the ion-exchange and surface complexation induced by interlayer Ti-O/Ti-OH of TCF-2. Specifically, the extended X-ray sorption fine structure (EXAFS) results, in combination with density functional theory (DFT) calculations, further confirm the Nd3+ is selectively adsorbed by forming surfaced complexes structure in the interlayer. And this is also evidenced by the decrease of Nd-O distances and high coordination number. The present results illustrate that alkaline metal ion-intercalated MXene could serve as a promising candidate to efficiently remove trivalent Fe3+ impurities for REEs recovery. [ABSTRACT FROM AUTHOR]

• A novel seismic intensity measure for underground structures is proposed. • The seismic response characteristics of underground structures can be considered. • The rigidity degradation of the dynamic system can be considered. • The period range significantly affecting the seismic response for underground structures is obtained. The purpose of this study is to present a novel approach to constructing intensity measures (IMs) for underground structures using seismic response spectrums. The proposed IM takes the form of an integral of the product of the response spectrum and an arbitrary function that reflects the relative importance of each range of period to the seismic response of underground structures. To obtain the arbitrary function, an artificial neural network (ANN) technique is employed. To demonstrate the effectiveness of this method, we develop two different soil-subway station dynamic systems, referred to as Case I and Case II. Based on both cases, the probabilistic seismic demand model (PSDM) for the proposed IM and eight existing IMs are developed. The performance of the proposed IM is compared with that of the existing IMs in terms of their proficiency, practicality, and efficiency, as well as their ability to describe the probabilistic distribution of damage measure (DM). The results indicate that the proposed IM outperforms the existing IMs since it has the highest proficiency for both cases. Moreover, the fragility curves calculated using the proposed IM are more effective than those calculated using traditional IMs, with narrower uncertainty ranges, which can help reduce the uncertainty in evaluating seismic risk. Comparing the function solved by the ANN with the seismic response of subway stations under different periods of harmonic excitation, it can be found that the solved function and the seismic response reach their peak points at the same period. This finding suggests that the proposed IM can account for the interaction between the surrounding soil and underground structures, as well as the softening of soil layers during earthquakes, making it a suitable IM for underground structures. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is an essential nutrient controlling plant growth and development through the regulation of basic metabolic processes. Soil P deficiency is one of the major limiting factors for sustainable crop production worldwide. Previous studies have demonstrated that silicon (Si), as a beneficial element, promotes plant nutrition, growth, development, and responses to low P (LP) stress; however, the molecular mechanisms underlying Si-mediated LP tolerance remain largely unclear. Here, we found that LP + Si treatment increased the net photosynthetic rate and shoot fresh weight by 34.3%, and 121.3%, respectively compared with LP alone. RNA-sequencing and metabolomic analyses were subsequently performed with tomato plants grown under control and P depleted conditions with or without Si amendment. RNA-sequencing showed that Si supply alters not only the expression of genes involved in the metabolism of carbon (C), nitrogen (N), and P but also phosphorylation processes and metabolism of glutathione and reactive active oxygen in tomato roots. Si also affected the expression of genes encoding major transcription factors such as WRKY and MYB under LP stress. Moreover, a set of genes encoding the enzymes or regulators of organic acid (OA) metabolism or secretion were differentially expressed in Si-treated P deficient roots compared with those in LP stress alone. Furthermore, the metabolomic analysis showed that the levels of several OAs were significantly elevated in Si-treated P deficient roots. Taken together, these results indicate that exogenous Si increases the secretion of OAs by modulating C/N metabolism in LP-treated tomato roots and thereby improving plant growth under LP stress. • Silicon (Si) improved antioxidant defense and mitigated low phosphorus (LP) stress. • RNA-sequencing revealed regulation of GSH and ROS metabolism by Si under LP stress. • Si also altered the transcripts of major transcription factors such as WRKY and MYB. • Genes involved in organic acid (OA) metabolism were differentially modulated by Si. • Metabolomic analysis showed accumulation of OAs in Si-treated roots under LP stress. [ABSTRACT FROM AUTHOR]

Highlights • Endothall amine efficacy was greater when plants were exposed in moving water. • Endothall amine was less potent as it aged in water solutions. • Potency was generally reduced from 12 h after application. Abstract The amine formulation of endothall is a herbicide that may be applied to flowing irrigation canals to control submerged aquatic weeds and algae. We undertook a bioassay experiment to simulate the effects of water movement and increasing distance away from an application point on control of aquatic weeds. We exposed two submerged aquatic plants (Elodea canadensis and Vallisneria australis) to endothall amine solutions. This was done a) with solutions that were aged for 0, 12, 24 and 48 h prior to plant exposure, to simulate the effect of distance downstream of the application point, and b) in three hydrodynamic environments: quiescent, low-flow and high-flow. Endothall amine was less potent on both species as the solution aged, such that potency was generally reduced from 12 h after application. The concentration of endothall acid did not decrease in the exposure tanks during the experiment, suggesting that there is a change of the endothall amine molecule as it ages in water, which reduces the herbicide's potency. Endothall amine efficacy was greater for both species when plants were exposed in moving water compared to quiescent water. We propose that the increased efficacy in moving water is caused by a reduction in the thickness of the aqueous diffusive boundary layer in the hydrodynamic environment, thus increasing the rate of endothall amine diffusion into the plant tissue. This information can be used to improve management of submersed aquatic weeds with endothall amine and to understand its potential impact on non-target aquatic plants as herbicide-treated water moves away from the area of application. [ABSTRACT FROM AUTHOR]

Several novel orange emission supramolecular phosphorescent polymers (SPPs) with different counterions of PF 6 −, Br− and BIm 4 - have been developed for polymer light-emitting diodes. The formation of SPPs, utilizing efficient non-bonding assembly of dibenzo-24-crown-8-tethered iridium complex and dibenzylammonium-functionalized fluorene-dibenzothiophene-S,S-dioxide cooligomer, are monitored by 1H NMR and viscosity measurement. The influences of different counterions on the optical, thermal and electroluminescent (EL) properties of the resulting SPPs, as well as the supramolecular assembly behavior are investigated in detail. These SPPs display high glass transition temperatures of ca. 100 °C. The single-emissive-layer PLED with SPP-PF 6 exhibits the highest device efficiency of 12.32 cd A−1 with the Commission Internationale de L'Eclairage (CIE) coordinates of (0.57, 0.43). More importantly, owing to "spacer" effect of the large BIm 4 - counterion, the device based on SPP-BIm 4 show very low efficiency roll-off. Supramolecular phosphorescent polymers (SPPs) with different counterions of PF 6 −, Br− and BIm 4 - have been developed for orange polymer light-emitting diodes, which exhibit good thermal stability and excellent electroluminescent properties. Image 1 • SPPs with different counterions of PF 6 −, Br− and BIm 4 - are obtained. • All the SPPs display orange light-emitting with a CIE coordinates of (0.57, 0.43). • The PLEDs based on SPP-PF 6 exhibited a highest LE of 12.32 cd A−1. • Due to "spacer" effect, the device with SPP-BIm 4 shows very low efficiency roll-off. [ABSTRACT FROM AUTHOR]