Biological electricity generation system based on mitochondria-nanochannel-red blood cells.

The high-efficiency energy conversion process in organisms is usually carried out by organelles, proteins and membrane systems. Inspired by the cellular aerobic respiration process, we present an artificial electricity generation device, aimed at sustainable and efficient energy conversion using biological components, to demonstrate the feasibility of bio-inspired energy generation for renewable energy solutions. This approach bridges biological mechanisms and technology, offering a pathway to sustainable, biocompatible energy sources. The device features a mitochondria anode and oxygen-carrying red blood cells (RBCs) cathode, alongside a sandwich-structured sulfonated poly(ether ether ketone) and polyimide composite nanochannel for efficient proton transportation, mimicking cellular respiration. Achieving significant performance with 40 wt% RBCs, it produced a current density of 6.42 mA cm-2 and a maximum power density of 1.21 mW cm-2, maintaining over 50% reactivity after 8 days. This research underscores the potential of bio-inspired systems for advancing sustainable energy technologies.

Bio-inspired High-Performance Artificial Ion Pump Mediated by Subnanoscale Dehydration Hydration Effects.

The energy conversion in plant chloroplast is carried out by pumping protons into the thylakoid for driving ATP synthesis. Inspired by ion active transport in living organisms, we attempted to design an artificial ion pump induced by subnanoconfinement effects. This ionic device uses two polarity functional nanoporous films as ion-selective valves at both ends and UiO-66 metal-organic framework-filled microchannels as ion storage cavities. In the charging process, ions could be pumped into the central cavities by nanovalves, which produced an ion gradient 10 to 100 times higher than the bulk, and were trapped within the subnanocages by dehydration. In the discharging process, the enriched ions were rehydrated and slowly released by the surface charge of the nanovalves, producing a sustainable ion current. The ion storage efficiency of this nanofluidic device could be improved to 60.3%, and the release time of ion current was also prolonged by 1 order of magnitude. This work combines the active and passive transport of ions to realize fast storage and slow release of ionic current, which provides an ion gradient-mediated novel energy conversion strategy.

Polyacrylonitrile nanofibrous membrane composited with zeolite imidazole skeleton-8 and silver nanoclusters for efficient antibacterial and emulsion separation.

Oily wastewater discharged by industrial development is an important factor causing water pollution. Membrane separation technology has the advantages of low cost, simple operation, and high efficiency in the treatment of oily wastewater. However, membrane materials are easily eroded by microorganisms during long-term storage or use, thereby resulting in reduced separation efficiency. Herein, a zeolite imidazole skeleton-8@silver nanocluster composite polyacrylonitrile (ZIF-8@AgNCs/PAN) nanofibrous membrane was fabricated by electrospinning and in situ growth technology. The surface chemistry, morphology, and wettability of the composite membranes were characterized. The carboxyl groups on the surface of hydrolyzed PAN nanofibers, which can be complexed with zinc ions (Zn2+), are utilized as growth sites for porous metal organic frameworks (ZIF-8). Meanwhile, AgNCs are loaded into ZIF-8 to achieve stable hybridization of ZIF-8@AgNCs and nanofibers. The loading quantity of ZIF-8@AgNCs, which can dominantly affect the surface roughness and the porosity of the membranes, is regulated by the feeding amount of AgNCs. The ZIF-8@AgNCs/PAN membrane achieves effective oil-water separation with high separation efficiency toward petroleum ether-in-water emulsion (98.6%) and permeability (62 456 ± 1343 Lm-2 h-1 bar-1). Furthermore, the ZIF-8@AgNCs/PAN membrane possesses high antibacterial activity against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus), which is beneficial for the long-term storage and use of the membrane.

Bioinspired High-Strength Montmorillonite-Alginate Hybrid Film: The Effect of Different Divalent Metal Cation Crosslinking.

The natural nacre has a regular ordered layered structure of calcium carbonate tablets and ion crosslinking proteins stacked alternately, showing outstanding mechanical properties. Inspired by nacre, we fabricated different divalent metal cation-crosslinked montmorillonite-alginate hybrid films (MMT-ALG-X2+; X2+ = Cu2+, Cd2+, Ba2+, Ca2+, Ni2+, Co2+ or Mn2+). The effect of ionic crosslinking strength and hydrogen bond interaction on the mechanical properties of the nacre-mimetics was studied. With the cations affinities with ALG being increased (Mn2+ < Co2+ = Ni2+ < Ca2+ < Ba2+ < Cd2+ < Cu2+), the tensile strength of nacre-mimetics showed two opposite influence trends: Weak ionic crosslinking (Mn2+, Co2+, Ni2+ and Ca2+) can synergize with hydrogen bonds to greatly increase the tensile properties of the sample; Strong ionic crosslinking (Ba2+, Cd2+, Cu2+) and hydrogen bonding form a competitive relationship, resulting in a rapid decrease in mechanical properties. Mn2+ crosslinking generates optimal strength of 288.0 ± 15.2 MPa with an ultimate strain of 5.35 ± 0.6%, obviously superior to natural nacre (135 MPa and 2%). These excellent mechanical properties arise from the optimum synergy of ion crosslinking and interfacial hydrogen bonds between crosslinked ALG and MMT nanosheets. In addition, these metal ion-crosslinked composite films show different colors, high visible transparency, and excellent UV shielding properties.

A procedure for comparing the ecological status and transformation measures in an anthropized coastal area.

The overall vitality and quality of the coastline can be improved through ecological transformation; ecological status assessment can scientifically guide this modification by putting forward a transformation plan for the coastline. This study took the Shenzhen Bay area between Hong Kong and Shenzhen as the study area to build an index system and combined it with quantitative and qualitative methods by designing the code of data processing, calculation, and analysis through the MATLAB platform, with the goal being to put forward the directions and suggestions for coastline transformation based on the analysis of results. The results and conclusions are as follows: (1) The key aspects of the ecological transformation of the Shenzhen Bay Coastline are water quality, coastal wetland restoration, landscape diversity, beach stability, and infrastructure improvement. (2) Actions to promote these aspects include overall shoreline control of water pollution, cultural landscape implantations, the improvement of existing infrastructure, and the restoration of selected beach sand regions, mangrove wetlands, and eroded shorelines. Suggestion includes the critical support which comes from the public needs for information acquisition and science education, in addition with the policy and management, all should be formulated into the transformation plan. The index system can be applied to other regions at home and abroad, and the results and conclusions based on the index system could also provide criteria for planning the ecological transformation process.

"Ion Pool" Structural Ion Storage Device: A New Strategy to Collect Ions by Nanoconfinement Effects.

Ion storage structure widely exists in organisms, which is used to harvesting energy in environment and converting it into ion concentration gradient to maintain complex life activities. The construction of ion storage structures relies on isolating the biological body fluids by biofilm systems, which can also be regarded as local ions confinement. Mimicking this ions storage process, an "ion pool" structural ion storage device is proposed in this research by artificial ion nanochannels, which can transform the electric power into ion concentration gradient. It is consisted of micrometer-sized ions reservoir and nanosized ions filters. Ions can be isolated within the "pool" and performed ultrahigh ions enrichment or depletion behavior deviated from bulk. Through numerical simulation by Poisson-Nernst-Planck equations, "ion pool" structural device achieves nearly 20 000 rectification ratio with low surface charge. An "ion pool" structural ions storage device is also constructed with block copolymer and polyethylene terephthalate composite membranes, a super high rectification ratio of 3184.0 is achieved from the experiment, which is the highest reported so far. The ion storage efficiency of the device reaches 14.90%, which is an order of magnitude better than non-"ion pool" structural nanofluid devices.

Gap Confinement Effect of a Tandem Nanochannel System and Its Application in Salinity Gradient Power Generation.

As an important nanofluidic device, an artificial ion nanochannel could selectively transport ions inside its nanoconfinement space and the surface charge of the pore wall. Here, confinement effects were realized by tandem nanochannel units, which kept their cascade gaps less than 500 nm. Within these gaps, ionic conductance was governed by the surface charge density of the channel unit. Cations could be sufficiently selected and enriched within this confined space, which improves the cation transfer number of the system. Therefore, the tandem nanochannel system could greatly improve the diffusion potential and energy conversion efficiency in the salinity gradient power generation process. Poisson-Nernst-Planck equations were introduced to numerically simulate the ionic transport behavior and confirmed the experimental results. Finally, the gap confinement effect was introduced in the porous cellulose acetate membrane tandem nanochannel system, and a high output power density of 4.72 W/m2 and energy conversion efficiency of 42.22% were achieved under stacking seven channel units.

A highly sensitive acetylcholinesterase electrochemical biosensor based on Au-Tb alloy nanospheres for determining organophosphate pesticides.

Accurately detect the residues of organophosphate pesticides (OPs) in food and environment is critical to our daily lives. In this study, we developed a novel acetylcholinesterase (AChE) biosensor based on Au-Tb alloy nanospheres (NSs) for rapid and sensitive detection of OPs for the first time. Au-Tb alloy NSs that with good conductivity and biocompatibility were produced with a mild hydrothermal. Under optimal conditions, the AChE biosensor was obtained by a simple assembly process, with a big linear range (10-13-10-7M) and the limit of detection was 2.51 × 10-14M for the determination of methyl parathion. Moreover, the determination of methyl parathion with the prepared biosensor presented a high sensitivity, outstanding repeatability and superior stability compared with other reported biosensors. Through the determination of tap water and Yanming lake samples, it was proved that the modified biosensor with satisfactory recoveries (96.76%-108.6%), and are realizable in the determination of OPs in real samples.

One-Step Fabrication of a Micro/Nanosphere-Coordinated Dual Stimulus-Responsive Nanofibrous Membrane for Intelligent Antifouling and Ultrahigh Permeability of Viscous Water-in-Oil Emulsions.

Membrane fouling is a major challenge for long-term oil/water separation. The incomplete degradation of organic pollutants or membrane damage exists in the common methods of membrane regeneration. Herein, a dual-responsive nanofibrous membrane with high water-in-oil emulsion separation efficiency and smart cleaning properties is reported, which shows complete restoration of its original separation performance. The pH-responsive and upper critical solution temperature (UCST)-type thermoresponsive nanofibrous membrane with a micro/nanosphere structure was developed via a one-step-blending electrospinning strategy. The membrane displays high hydrophobicity/oleophilicity at pH 7 and 25 °C and hydrophilicity/oleophobicity at pH 3 and 55 °C. As a result, it exhibits an ultrahigh permeability of 60528.76 L m-2 h-1 bar-1 and a separation efficiency of 99.5% for water-in-D5 emulsions at room temperature (25 °C). Moreover, the contaminated membranes could be easily reclaimed by being rinsed with warm acidic water (pH 3 and 55 °C). The membrane maintained high separation performance after being used for multiple cycles, indicating its scalable application for purifying emulsified oil. This study provides a facial method of constructing membranes with multiscale hierarchical structures and a new idea for the design of recyclable oil/water separation membranes.

Spatial Trade-Offs and Temporal Evolution of Multiple Ecosystem Services in a Marine-Terrestrial Urban-Agglomeration Zone.

It takes some time for changes to come in ecosystem services, and trade-offs occur in the process of changes. As opposed to a point in time, we use data spanning the years 2000-2005, 2005-2010, and 2010-2015 to study this research. After quantifying types of ecosystem services, this paper uses spatial correlation analysis and root-mean square deviation (RMSD) method to explore the relationships among ecosystem services and calculate the degree of spatial trade-offs (DT). Results show that the construction land increased substantially albeit at a declining rate of growth, and the degree of trade-offs (DT) increased with nontrivial differences in space. The hotspots for trade-offs are spatially aggregated in some areas but have varying patterns between ecosystem service pairs. The increasing area (IA) of construction land does not promote increased DT until the former reaches a certain threshold. With the exception of land use changes, type of industrial development is one of the key factors that influence the trade-offs of ecosystem services in the research region. We apply the models and methods used in this research to practice and discuss the practical value of our results for planners and decision makers vis-à-vis the design and instigation of appropriate development strategies.

Insights into plasmon induced keto-enol isomerization.

Chemical reactions that are driven by plasmon-induced hot carriers are a timely topic of interest to chemists and material scientists as they provide catalytic alternatives that may reduce cost and/or waste. Herein, we monitored the localized surface plasmon resonance-induced keto-enol isomerization process of 2-mercapto-4(3H)-quinazolinone (MQ) by time-dependent surface enhanced Raman scattering (SERS), where the MQ molecules are adsorbed on gold nanoparticles (GNP) surface by Au-S bonds. The mechanism of keto-enol isomerization has been successfully investigated, and it is found that the isomerization is induced by hot hole transfer from GNPs to the adsorbed molecules. The present investigation could provide significant insights into hot hole catalyzed chemical reactions via SERS spectra and theoretical calculations.

Ion Transport Behaviors of Nanofluidic Diode Bichannel Systems in the Independent and Synergistic Cascade Mode.

The nanofluidic diode device was a significant ionic transistor. Its multiple cascades could realize diversified ion transport behaviors and information processing functions. Different cascade modes of channel units will affect the response current properties of multichannel systems. Inspired by independent and synergistic effects in semiconductor transistors, artificial conical nanoporous bichannel systems were investigated in separation and stacking cascade modes to discuss their different ion transport behaviors. The dynamic resistance fitting method was adopted to discuss the properties of each circuit components in the bichannel system for analyzing the circuit properties in different cascade modes. In the stacking mode, electric field interactions at the heterojunctions between channel units dominated the ionic transport properties, and response current of the bichannel system was influenced by the channel unit cascade sequence. In the separation mode, channel units transport ions independently, and the cascade sequence had little effect on response current properties of the system. These promising results provide a new strategy to design and build a series of artificial composite nanochannels with multifunction and intelligence.

Bioinspired Ternary Artificial Nacre Graphene Oxide/Carboxyl Functionalized Single-Walled Carbon Nanotubes/Konjac Glucomannan with Enhanced Mechanical Properties.

Inspired by the nacre layered multistage structure and high toughness and strength of the unity of mechanical properties, a graphene oxide/carboxyl functionalized single-walled carbon nanotubes/konjac glucomannan (GO-SC-KGM) nanocomposite is successfully fabricated through a vacuum filtration method for the first time. The GO nanosheets with carboxyl and hydroxyl groups, SC with carboxyl groups, and the KGM molecule chains with abundant hydroxyl groups could easily form hydrogen bonding networks, resulting in a strong interface interaction. The tensile strength of prepared GO-SC-KGM nanocomposites reaches 311.4 ± 9.2 MPa. At the same time, it can maintain toughness up to 11.1 ± 0.5 MJ m-3. Its strength and toughness are much higher than nacres and other nacre-like GO-base composites. Thus, this kind of SC enhances high tensile strength and toughness, and the bioinspired nanocomposite exhibits promising potential applications for food packaging, aerospace, tissue engineering, or as a replacement for conventional chemical synthetic organic based materials.

Assessment of Regional Ecosystem Health-A Case Study of the Golden Triangle of Southern Fujian Province, China.

Intensifying urbanization and rapid population growth in Fujian Province, China, has caused pollution of air and water resources; this has adversely impacted ecosystems and human health. China has recently begun pursuing a massive infrastructure and economic development strategy called the Belt and Road Initiative, which could potentially cause further environmental damage. Evaluations of ecosystem health are therefore a first step towards identifying the potential impacts from the development and planning sustainable development strategies in the Golden Triangle of Southern Fujian. To this end, our study analyzed landscape patterns and evaluated ecosystem health in this region. We used an index system method to develop a pressure⁻state⁻response (PSR) model for assessing the region’s ecosystem health. We found that: (1) the landscape type with the greatest area in the study region is cultivated land and there were no areas that were undisturbed by human activity; (2) the overall ecological health of the region is good, but there is distinct variation across the region. This study incorporates the landscape pattern into an evaluation of ecosystem health. Using counties as evaluation units, we provide a general evaluation index for this scale. The methods reported here can be used in complex ecological environments to inform sustainable management decisions.

Direct determination of the tumor marker AFP via silver nanoparticle enhanced SERS and AFP-modified gold nanoparticles as capturing substrate.

The authors describe a rapid and direct SERS-based immunoassay for the determination of AFP, an important marker for diagnosis of hepatocellular carcinoma. Silver nanoparticles (AgNPs; 36 nm i.d.) serve as a support to immobilize antibody and as a SERS intensifier, and AFP-modified gold nanoparticles are employed as capturing substrate. Direct and quantitative detection of AFP is accomplished with a limit detection as low as 5 ng·mL-1. Compared to assays based on the use of metal nanoparticles, the use of gold-silver nanoparticle heterodimers as an active SERS substrate can save costs because only a single antibody is required. Moreover, the high selectivity and good linear relationship of detecting AFP in fetal bovine serum indicates its potential applicability for the direct analysis of clinical samples. Graphical abstract Direct and quantitative determination of AFP antigen utilizing SERS has been was successfully presented and applied to detect alpha fetoprotein antigen in fetal bovine serum with detection limit of 2 ng•mL-1.

A CO2-tunable plasmonic nanosensor based on the interfacial assembly of gold nanoparticles on diblock copolymers grafted from gold surfaces.

A general stepwise strategy for the fabrication of CO2-tunable plasmonic nanosensors was described for the first time, based on gold surface functionalization by CO2-responsive poly(N,N-diethylaminoethyl methacrylate) (PDEAEMA) brushes via a surface-initiated atom transfer radical polymerization (SI-ATRP) method, then the extremity of PDEAEMA was functionalized by linking the polyacrylamide (PAAm) brushes via ATRP, where they were assembled with gold nanoparticles (AuNPs) efficiently by altering the deposition time. The swelling-shrinking states of the PDEAEMA brushes can be tuned just by passing CO2 and N2 through a solution alternately. The unique plasmonic surface-enhanced Raman scattering (SERS) sensing properties of these stimulable substrates were investigated using 4-mercaptophenol (4MPh) as a molecular probe. When alternating CO2 and N2 bubbling in the water solution, the reversible switching of the SERS signals was complete. By in situ contact-mode atomic force microscopy, the thickness of the polymer layer was observed to be 26 nm in CO2 saturated water, and after N2 bubbling to remove CO2 it decreased to 15 nm, causing the AuNPs to move near to the gold surface. Meanwhile, the distance between the nearby AuNPs becomes smaller, and the surface coverage (φ) of the AuNPs increased from 27% to 35%. The reported CO2-responsive plasmonic nanosensor provided a dynamic SERS platform, with reversible regulation for electromagnetic coupling between the AuNPs and the gold surface, and between nearby AuNPs.