Attraction Mechanism Research Articles

The Hoverfly Attracting Property of a Methyl Salicylate-Containing (E)-β-Farnesene Analog (3e) and Potential Mechanism by Mediating the EcorOBP15 and EcorOR3.

Using natural enemies provides a sustainable method to control major agricultural pests. Hoverflies are significant natural enemies of aphids and efficient pollinators. Herbivore-induced plant volatiles (HIPVs), including (E)-β-farnesene (EBF) and methyl salicylate (MeSA), are key olfactory cues mediating hoverflies behavior. Our previous work identified compound 3e, an EBF analog containing a MeSA moiety, exhibited aphid-repelling and ladybug-attracting activities. However, whether 3e can attract hoverflies remains unknown. Therefore, this study explored the attractant property and potential mechanism of 3e toward hoverflies. Laboratory bioassays and field trials indicated 3e has an obvious hoverfly attracting property. The attraction mechanism studies demonstrate that, similar to EBF, 3e can interact with EcorOBP15 and EcorOR3, with its greater chemical softness, larger hydrophobic and charge regions enhancing these interactions. Furthermore, 3e exhibited low toxicity to honeybees (Apis mellifera) and hoverflies (Eupeodes corollae). Consequently, 3e could be a promising eco-friendly behavioral regulator for integrated aphid management in sustainable agriculture.

Synergistic effect of β-ocimene on Hyphantria cunea sex pheromone and its potential attraction mechanism related to Ca2+ stimulation

Synergistic effect of β-ocimene on Hyphantria cunea sex pheromone and its potential attraction mechanism related to Ca2+ stimulation

Superconductivity from Domain Wall Fluctuations in Sliding Ferroelectrics

Bilayers of two-dimensional van der Waals materials that lack an inversion center can show a novel form of ferroelectricity, where certain stacking arrangements of the two layers lead to an interlayer polarization. Under an external out-of-plane electric field, a relative sliding between the two layers can occur, accompanied by an interlayer charge transfer and a ferroelectric switching. We show that the domain walls that mediate ferroelectric switching are a locus of strong attractive interactions between electrons. The attraction is mediated by the ferroelectric domain wall fluctuations, effectively driven by the soft interlayer shear phonon. We comment on the possible relevance of this attraction mechanism to the recent observation of an interplay between sliding ferroelectricity and superconductivity in bilayer Td−MoTe2. We also discuss the possible role of this mechanism in the superconductivity of moiré bilayers. Published by the American Physical Society 2024

Experimental and theoretical insights into the adsorption mechanism of methylene blue on the (002) WO3 surface

This work investigates the efficiency of green-synthesized WO3 nanoflakes for the removal of methylene blue dye. The synthesis of WO3 nanoflakes using Hyphaene thebaica fruit extract results in a material with a specific surface area of 13 m2/g and an average pore size of 19.3 nm. A combined theoretical and experimental study exhibits a complete understanding of the MB adsorption mechanism onto WO3 nanoflakes. Adsorption studies revealed a maximum methylene blue adsorption capacity of 78.14 mg/g. The pseudo-second-order model was the best to describe the adsorption kinetics with a correlation coefficient (R2) of 0.99, suggesting chemisorption. The intra-particle diffusion study supported a two-stage process involving surface adsorption and intra-particle diffusion. Molecular dynamic simulations confirmes the electrostatic attraction mechanism between MB and the (002) WO3 surface, with the most favorable adsorption energy calculated as -0.68 eV. The electrokinetic study confirmed that the WO3 nanoflakes have a strongly negative zeta potential of -31.5 mV and a uniform particle size of around 510 nm. The analysis of adsorption isotherms exhibits a complex adsorption mechanism between WO3 and MB, involving both electrostatic attraction and physical adsorption. The WO3 nanoflakes maintained 90% of their adsorption efficiency after five cycles, according to the reusability tests.

Optical pulling of Mie particles along a curved path by optical scattering forces.

Optical pulling along straight trajectories has been successfully demonstrated for both dipolar and Mie particles using optical gradient and/or scattering forces over the past decade. However, much less attention is devoted to the pulling along curved paths, particularly for Mie particles, since the mechanism of continuous attraction based on intensity gradients is effective only for dipolar particles, thus limiting its practical applications. Here, we demonstrate the optical pulling of Mie particles with gain along a parabolic trajectory immersed in a two-dimensional vector Airy beam. Numerical results based on the decomposed force expressions exhibit that the longitudinal optical pulling effect is overwhelmingly dominated by the optical scattering force, while the optical gradient force has a negligible contribution. In addition, the Mie particle is shown to be transversely trapped stably in the main lobe of the Airy beam via the transverse gradient force in favor of the realization of optical pulling. Such an optical pulling phenomenon can also be observed for a gold particle coated with a suitable gain shell. Our findings may provide new insights into the customization of optical pulling in curved paths.

Extrinsic and intrinsic regulation of blood feeding in mosquitoes.

Mosquitoes obtain large amounts of blood from hosts in a short period of time. To efficiently obtain high-quality blood without being noticed by the host, mosquitoes sense external factors such as the taste of the host blood and the surrounding environment, and integrate these signals with their own internal information to determine whether to initiate blood feeding and how long to continue feeding. With the development of gene editing and behavior monitoring techniques, the factors that control blood feeding are being identified. Elucidating the factors that contribute to blood feeding is expected to provide new ideas for artificially controlling blood feeding, which has often been overlooked behind host attraction mechanisms. Furthermore, understanding salivary components, mechanisms controlling satiety in feeding, and differences between sugar feeding and blood feeding would help us understand how some mosquitoes have adopted and developed blood feeding over the course of evolution.

On the calibration and improvement of human mobility models in intercity transportation system

As one of the research highlights of physics-level modelling, human mobility has generated numerous universal laws over the past decades. However, the majority of research has concentrated on the intracity networks, leaving the intercity mobility systems with insufficient attention despite its increasingly crucial role in the development of urban agglomerations. Related research gaps further extend to the limited understanding of spatiotemporal heterogeneity in intercity human mobility. To bridge these gaps, our study systematically validated and improved the modelling framework of intercity mobility flows utilizing real-world data sources. Specifically, building upon the nationwide Location-based Services (LBS) datasets in China, the applicability of classic human mobility models, including gravity model and intervening opportunities-class models, was extensively explored in the intercity domain by developing fitting models that incorporated multi-class urban attributes. Then, we contributed to proposing improved models that consider the diverse attraction effect of the origin and potential destinations. Moreover, our research scope was expanded to incorporate spatiotemporal heterogeneity through model comparisons among various city sets during both regular period and holiday. The findings suggested that our improved models effectively enhance the modelling accuracy while strengthening the explanatory power. They especially demonstrate a balanced performance even when handling datasets with spatiotemporal heterogeneity. Consequently, this study provides valuable insights into understanding intercity human mobility from the intrinsic mechanism of opportunity attraction. Our models hold practical significance in accurately modelling intercity mobility flows utilizing observable urban attributes and spatial layouts, further providing effective tools for preemptive traffic management.

Enhanced adsorption of tylosin by ordered multistage porous carbon and efficient in-situ regeneration of saturated adsorbents by activated persulfate oxidation: Performance, mechanism and multiple cycles

In this study, a novel ordered multistage porous carbon (OMPC) with a micro-mesoporous structure was prepared and used for the removal of tylosin (TYL). The porous material, carbonized at 900 °C (OMPC-900), exhibited micro-mesoporous structures with pore sizes of 0.71 nm and 3.63 nm, while had a specific surface area of 1300.02 m2 g−1. OMPC-900 demonstrated a maximum adsorption capacity of 341.28 mg g−1 for TYL in water by electrostatic attraction, hydrogen bonding, π-π interactions, and pore-filling mechanisms, which is 6.41 times higher than that of activated carbon. The TYL-saturated adsorbents could be efficiently regenerated by in-situ oxidation through the activation of persulfate (PDS), achieving a regeneration rate of 94.17%, significantly higher than that of activated carbon (55.22%). The excellent regeneration performance may be attributed to the presence of -C=O and graphitic carbon in the adsorbent, which promotes the production of free radicals (•OH, SO4•- and •O2−) and non-free radicals. Among these, the non-radical pathways (1O2 and electron transfer) played a key role in the degradation of TYL loaded on the adsorbent. OMPC-900 maintained stable regenerative adsorption performance of 80.85% after five in-situ regeneration, and the normalized adsorption capacity per unit surface area increased from 0.21 to 0.39 mg m−2, which may be due to that the increase in oxygen-carbon ratio and surface defects improved the adsorption sites activity of the regenerated adsorbent. In comparison to conventional pyrolysis and organic solvent elution, oxidative regeneration through the activation of PDS is a more efficient and sustainable method.

The Innovative Logic of the Communist Party's View on Scientific and Technological Talents in the New Era

This article thoroughly examines the innovative logic of the Communist Party's view on scientific and technological talents in the new era, providing a comprehensive analysis of core aspects such as talent cultivation, attraction, selection, management, and motivation. Under the new era's backdrop, the Party's understanding of scientific and technological talent work has become increasingly profound, proposing a series of innovative principles and strategies. These principles not only reflect a comprehensive and systematic consideration of scientific and technological talent work, but also provide solid theoretical foundations and practical guidance for technological innovation and talent development.Specifically, in the cultivation of scientific and technological talents, emphasis is placed on practice and innovation as the core, focusing on comprehensive quality cultivation, aiming to create a high-quality talent team that can adapt to the technological development needs of the new era. In attracting scientific and technological talents, an open and inclusive approach is adopted, actively introducing outstanding talents from both domestic and foreign sources, building a diversified talent attraction mechanism. When selecting scientific and technological talents, evaluation criteria are based on ability and contribution, ensuring fairness and scientific rigor in the selection process. In terms of management and motivation, emphasis is placed on personalized management and effective incentives to stimulate the innovative vitality of scientific and technological talents.By implementing these principles, it will effectively promote the gathering and growth of scientific and technological talents, providing strong talent support for China's scientific and technological cause and economic and social development, further driving technological innovation and social progress in the new era.

Competitive sequestration behavior and mechanism of Cd2+, Pb2+and Ni2+ ions from single, binary and ternary metal laden solution by Hevea brasiliensis wood sawdust (HBS)

HeveaBrasiliensis wood sawdust (HBS), a lignocellulosic material, was employed for the eradication of Cd(II), Pb(II), and Ni(II) from synthetic single and multi-metalsystem. In the realm of multimetal adsorption, HBS exhibited the most substantial adsorption capacities for heavy metals, in the order: Pb(II) > Cd(II) > Ni(II). Experiments involving batch process were carried out to explore the rolesofpH, contact duration, HBS quantity, and preliminary metal concentrations on the adsorption capacity. Optimal conditions for biosorption of metal ions were determined as pH 5.0, dosage of 7 gL−1, and an equilibrium time of 90 min. The pseudo-second-order kinetics andLangmuirisotherm had a favorable alignment with the biosorption of all individual metal ions. Adsorption capacity was 8.45, 13.01 and 6.04 mg g− 1 for Cd, Pb and Ni respectively in single metal system. In binary and ternary system the capacity and adsorption percentages decreases significantly due the presence of competitive metal ions. HBS demonstrated effectiveness in treating real wastewater containing Cd2+, Pb2+and Ni2+ ionsin both single and mixed metal solutions, highlighting the necessity of thoroughly considering the impact of competitive adsorption. SEM with EDS results indicated single metal fixing in a multi-ion solution followed complex mechanisms. The surface area and functional group studies were conducted utilizing BET and a FTIR Spectrometer. Electrostatic attraction and complexation mechanisms were identified as responsible factor for capturing metal ions to the active surfaces of the bio sorbent. Cost analysis reflected the adsorbent cost was $0.021 per liter of mixed contaminated ternary effluent (30 mg L−1).

Dynamical analysis of the low-temperature phase diagram of a cuprate superconductor

For a cuprate superconductor, specifically the yttrium barium copper oxide system, we analyze the low-temperature phase diagram consisting of the superconducting, pseudogap, and normal phases by using a phonon-mediated attraction and Coulomb repulsion mechanism. Through this analysis, we show this mechanism in the cuprate is quite important for its key dynamics. For the pairing mechanism, a variational method is developed and applied, and a generalized mean field theory is used to calculate the condensate energy and the energy gap of the quasiparticle. We obtain a self-consistent system of equations for these quantities. The superconducting and pseudogap phases, which involve pair-condensates, are assumed to be equilibrium systems of the condensate and normal subphases. The condition for the phase transition point is given by the equal total electronic energy gains. Assuming that the difference in the pairing range of the pair condensate is small between just above and below the transition temperature, computations are performed to solve the self-consistent system of equations. We find solutions compatible with experimental data. Plausible values of the energy gap in the superconducting phase and in the pseudogap phase are obtained. The present analysis shows that the phonon-mediated attraction and Coulomb repulsion mechanism itself is compatible with the experimental data. The importance of the screening effect through one-phonon exchange in the pairing mechanism and of the structure of the valence band is discussed.

Granular polyacrylonitrile with internal 3D channels for gold recovery from thiosulfate solution

Gold recovery technology is an urgent challenge in the industrialisation of thiosulfate-based gold extraction. Current materials used for gold recovery suffer from a lack of wear resistance and small particle size, which makes it difficult to separate the material from thiosulfate solutions. In this study, a cysteamine-functionalised granular polyacrylonitrile (cys-PANG) material containing three-dimensional channels was designed and synthesised. The results indicate that cys-PANG, prepared using a solvent exchange method, has remarkable adsorption capacity for gold, smooth outer surface, well-developed internal pore structure, high wear resistance, and controllable size, making it suitable for gold recovery from thiosulfate pulp. The adsorption of gold in a thiosulfate solution by cys-PANG followed the Freundlich isotherm and pseudo-second-order kinetic adsorption models with minimal pH dependence. Cys-PANG also demonstrated the effective adsorption of gold in a Cu(II)–ethanediamine (en)–S2O32− solution, even in the presence of copper and en interference. Both experimental results and theoretical calculations revealed that the interaction between cys-PANG and gold in the thiosulfate solution is predominantly characterised by charge attraction and ligand exchange mechanisms. Adsorption tests of cys-PANG in actual thiosulfate pulp demonstrated exceptional gold recovery properties and minimal wear even after 14 days of continuous stirring. This study presents a promising alternative methodology for the recovery of gold from thiosulfate pulp.

Coal gasification fine slag derived porous carbon-silicon composite as an ultra-high capacity adsorbent for Rhodamine B removal

The extensive release of industrial solid wastes and organic dyes has led to severe environmental pollution, underscoring the urgent need to recycle these solid wastes and to remove the dyes. Herein, a porous carbon-silicon composite (PC-SiO2) is synthesized using coal gasification fine slag (CGFS) as a precursor via an alkali (KOH) activation and an acid (HCl) etching process, and used as an adsorbent for the Rhodamine B (RhB) removal. The as-synthesized PC-SiO2 possesses an ultra-high specific surface area of 1275.63 m2/g, a large pore volume of 0.26 cm3/g, and enriched reactive functional groups (e.g., Si-OH and –COOH). Due to these features, the actual adsorption capacity and removal ratio of the PC-SiO2 for RhB were as high as 1383.72 mg/g and 92.25 %, respectively, at 298.15 K and pH = 7. Further studies indicate that the adsorption of RhB on PC-SiO2 fits both the pseudo-second-order kinetic model and the Langmuir model, with the maximum equilibrium adsorption capacity being 1388.89 mg/g as predicted by the Langmuir model. The adsorption process involves the electrostatic attraction, hydrogen bonding, π-π interaction, and pore-filling mechanism. This work not only offers a novel approach for removing organic dyes from industrial wastewater but also provides an effective strategy for producing high-value-added materials from industrial solid wastes.

Uncalcined Zn/Al Carbonate LDH and Its Calcined Counterpart for Treating the Wastewater Containing Anionic Congo Red Dye

In this investigation, Zn/Al carbonate layered double hydroxide (ZAC-LDH) and its derived material on calcination were synthesized for removing the anionic azo dye Congo red (CR) from wastewater. Numerous factors were methodically investigated, including temperature, adsorbent dosage, pH, starting Dye Concentration (DC), and contact time. The CR elimination percentage dropped as the initial DC increased from 25 mg/L to 100 mg/L at 30 °C for uncalcined LDH, and from 97.96% to 89.25% for calcined LDH. The pH analysis indicates that the highest level of dye removal was recorded within the acidic pH range through the electrostatic attraction mechanism. The sorption kinetics analysis results demonstrated that the pseudo-second-order kinetic model exhibited a stronger fit to both uncalcined LDH and CZA-LDH, with the maximum correlation coefficient value. The Van’t Hoff plots indicate the spontaneous nature of the physisorption process with a negative ΔG° (<−20 kJ/mol), while the endothermic adsorption process exhibited a positive ΔH°. The X-ray diffraction of calcined LDH reveals a significant intercalation of CR dye molecules, both prior to and following adsorption, showcasing a distinctive memory effect. The Brunauer–Emmett–Teller (BET) gas sorption measurements were performed to support the mesoporous nature of ZAC-LDH and CZA-LDH. The FTIR spectrum confirms the interaction of dye molecules on the surface of uncalcined and calcined LDH. These findings emphasize the efficacy of both the synthesized LDHs in removing CR dye, with CZA-LDH demonstrating superior efficiency compared to uncalcined LDH in the context of CR removal from wastewater.

Recovery of rare earth elements from mine wastewater using alginate microspheres encapsulated with zeolitic imidazolate framework-8

There is increasing demand and interest in efficient methods for the recovery of rare earth elements (REEs) from wastewater because of the growing concerns associated with the negative impacts of REEs-rich waste discharged on pristine ecosystems. Here, we designed a ZIF-8@ALG composite hydrogel by encapsulating zeolitic imidazolate frameworks-8 (ZIF-8) into sodium alginate and poly (vinyl alcohol) double cross-linked networks (ALG) for the recovery of REEs from mine wastewater. ZIF-8@ALG showed exceptional REEs adsorption performance with the most superior separation factor (Ho/Mn) of 597.5. For the REEs considered, the ZIF-8@ALG composite exhibited a preference for heavy REEs with high adsorption efficiencies (65.3 ∼ 97.2%) and distribution coefficients (2045.5 ∼ 28500.0 mL·g−1). Adsorption involved a combination of electrostatic attraction, complexation and ion exchange mechanisms. REEs adsorbed on ZIF-8@ALG could also be desorbed using sodium citrate via ion-exchange and complexation, thus achieving efficient REEs recovery. In addition, ZIF-8@ALG was stable and reusable, maintaining effective adsorption in wastewater over four consecutive cycles, where the optimal adsorption efficiency reached 80.0%. Overall, this study provided an effective and feasible method for the recovery of REEs in mine wastewater, and confirmed that ZIF-8-based materials have significant potential for REEs recovery applications in wastewater engineering treatment.

What enables ‘real social work’ in adult social work? Examining mechanism-based explanations

The enduring contradiction between managerialism and professional social work has been a central focus of social work research for decades. This article explores the feasibility of implementing the original values and ideals of social work in the face of the pervasive managerialism brought about by New Public Management, which has infiltrated nearly every sector of society. Utilising qualitative research conducted within adult social work on local public welfare agencies, we investigate the mechanisms that enable social workers to align with their ideal professional goals, referred to here as ‘real social work’, as outlined by social workers themselves. Our analysis, grounded in critical realism and the associated theoretical-methodological framework of CAIMeR theory, revealed five key mechanisms that facilitated real social work: the role-taking mechanism, the response mechanism, the organisational autonomy and responsibility mechanism, the collective attraction and cohesion mechanism, and the critical consciousness mechanism. Our findings suggest the need for further investigation of these mechanisms that empower social workers to resist managerialism and implement real social work in their daily work. This study advocates for prioritising professional aspirations and offers insights for advancing discussions in the realm of adult social work.

Large Organic Polar Molecules Tailored Electrode Interfaces for Stable Lithium Metal Battery.

Lithium (Li) metal batteries (LMBs) are deemed as ones of the most promising energy storage devices for next electrification applications. However, the uneven Li electroplating process caused by the diffusion-limited Li+ transportation at the Li metal surface inherently promotes the formation of dendritic morphology and instable Li interphase, while the sluggish Li+ transfer kinetic can also cause lithiation-induced stress on the cathode materials suffering from serious structural stability. Herein, a novel electrolyte designing strategy is proposed to accelerate the Li+ transfer by introducing a trace of large organic polar molecules of lithium phytate (LP) without significantly altering the electrolyte structure. The LP molecules can afford a competitive solvent attraction mechanism against the solvated Li+, enhancing both the bulk and interfacial Li+ transfer kinetic, and creating better anode/cathode interfaces to suppress the side reactions, resulting in much improved cycling efficiency of LMBs. Using LP-based electrolyte, the performance of LMB pouch cell with a practical capacity of ~1.5 Ah can be improved greatly. This strategy opens up a novel electrolyte designing route for reliable LMBs.

Large Organic Polar Molecules Tailored Electrode Interfaces for Stable Lithium Metal Battery

AbstractLithium (Li) metal batteries (LMBs) are deemed as ones of the most promising energy storage devices for next electrification applications. However, the uneven Li electroplating process caused by the diffusion‐limited Li+ transportation at the Li metal surface inherently promotes the formation of dendritic morphology and instable Li interphase, while the sluggish Li+ transfer kinetic can also cause lithiation‐induced stress on the cathode materials suffering from serious structural stability. Herein, a novel electrolyte designing strategy is proposed to accelerate the Li+ transfer by introducing a trace of large organic polar molecules of lithium phytate (LP) without significantly altering the electrolyte structure. The LP molecules can afford a competitive solvent attraction mechanism against the solvated Li+, enhancing both the bulk and interfacial Li+ transfer kinetic, and creating better anode/cathode interfaces to suppress the side reactions, resulting in much improved cycling efficiency of LMBs. Using LP‐based electrolyte, the performance of LMB pouch cell with a practical capacity of ~1.5 Ah can be improved greatly. This strategy opens up a novel electrolyte designing route for reliable LMBs.

Iron-lanthanum supported on graphite sheets for As(III) removal from aqueous solution: kinetics, thermodynamic and ecotoxicity assessment.

Graphene-based material is widely used to remove arsenic from water due to its layered structure with high surface area. Here, we have successfully synthesized Fe-La bimetallic modified graphite sheet materials to more efficiently remove As(III) from aqueous solution. The results showed that Fe-La-graphite sheets (FL-graphite sheets) have a larger specific surface area (194.28 m2·g-1) than graphite sheets (2.80 m2·g-1). The adsorption capacity of FL-graphite sheets for As(III) was 51.69mg·g-1, which was higher than that of graphite sheets (21.91mg·g-1), La-graphite sheets (26.06mg·g-1), and Fe-graphite sheets (40.26mg·g-1). The FL-graphite sheets conformed to the Freundlich and Dubinin-Radushkevich isotherm, and the maximum adsorption capacity was 53.62mg·g-1. The removal process obeys intra-particle diffusion and pore diffusion for As(III). The results of batch adsorption experiments and characterization analyses demonstrated that oxidation, ligand exchange, and inner sphere complexation mechanisms involved in the adsorption of FL-graphite sheets to As(III) in comparison with graphite sheets. In addition, electrostatic attraction mechanism was found vital in the adsorption. Ecotoxicity assessment revealed that FL-graphite sheets have little influence on rice germination and growth, but reduced the toxicity of As(III) to rice. Therefore, the FL-graphite sheets have good practical application value in purifying As(III) polluted water with litter ecotoxicity.

Preliminary evaluation of properties and performance of natural rubber (NR) latex band for microplastic capturing in seawater

Microplastic particles are emerging water-laden waste that cause a worrying concern towards the environment and humans health. Due to its small size and geometry, and uncertain surface properties, the microplastic waste capturing method in water is still evolving. To date, a number of findings report on the emergence of microplastic surface charging, especially when exposed to water environment. In this study, the natural rubber (NR) latex band was utilized to capture the microplastic waste via a surface capturing mechanism. The NR band was produced using a film casting and curing methods. The surface charging mechanism on the NR band was introduced via the usage of high amount of ZDEC accelerator and, periodic stretching and relaxation procedures. In this work, ZDEC was used as an accelerator for the rubber formulation, and surface charge booster for the NR band. The surface charge of the NR band generates electrostatic interaction with the microplastic waste in water. The polypropylene (PP) microplastic was captured via the surface attraction mechanism using the manufactured NR band. Based on FTIR analysis, the presence of PP microplastic can be quantified on the contaminated NR band surface. The NR band shows the improvement in tensile and tear properties and crosslink density, mainly due to high amount of ZDEC used. At ZDEC loading of 20 phr, the NR band recorded the highest surface potential value, and this is owing to the formation of Zn2+ complex ions on its surface. XRF analysis indicates that the increment of Zn content in the NR band with increasing ZDEC content, that suggests the formation of Zn2+ complex ions.