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Modern hydrometallurgy has been developing for more than 100 years and the related articles keep piling up. Based on a bibliometric analysis of the articles in Hydrometallurgy, the most authoritative journal in the field of hydrometallurgy, we try to catch the research and development trends from a global perspective. Firstly, keywords burstness shows that rare earth, recycling, lithium, ionic liquid, and thorium are the hotspots in recent years, and the economic and technological reasons behind them were discussed in depth. Secondly, the proportion of biohydrometallurgy grows fast from 5% to 13% and the related articles are almost all about bioleaching. There are some new directions such as direct preparation of materials in hydrometallurgical processes and ion-imprinted techniques. Thirdly, the advanced instrument analysis methods such as XAFS (X-ray absorption fine structure), gene sequencing, and micro-CT promote the deep understanding of hydrometallurgy mechanism. Finally, the cooperation network and contribution of the main institutes were mapped.

Mercury (Hg) is a heavy metal with high toxicity and easy migration; it can be enriched through the food chain, and cause serious threats to the natural environment and human health. So, the development of a method that can be used to detect mercury ions (Hg2+ ) in the environment, in cells, and in organisms is very important. Here, a new 7-hydroxycoumarin-derived carbonothioate-based probe (CC-Hg) was designed and synthesized for detection of Hg2+ . After addition of Hg2+ , a large fluorescence enhancement was observed due to the formation of 7-hydroxyl, which reinforced the intramolecular charge transfer process. The CC-Hg probe had good water solubility and selectivity. Moreover, the probe was able to detect Hg2+ quantitatively over the concentration range 0-2 μM and with a detection limit of 7.9 nM. Importantly, we successfully applied the probe to detect Hg2+ in water samples, in living cells, and in zebrafish. The experimental results demonstrated its potential value in practical applications.

In this work, by taking full advantage of the transformation of nitro group into amino moiety under the direct reduction of CO, a new metal-free colorimetric and near-infrared fluorescent probe NIR-CO for rapid and specific tracing of intracellular CO has been constructed, and it also become the first reaction-based near-infrared fluorescent probe for CO detection without additional reagents. Probe NIR-CO could quantitatively detect CO at the nanomolar level and the detection limit was calculated as low as 6.1 nM. Additionally, probe NIR-CO with preeminent sensing properties was successfully applied to monitor the fluctuations of endogenous CO levels in living systems. In particular, the up-regulation of heme oxygenase-1 (HO-1) caused by transient glucose deprivation (TGD) in living cells and the down-regulation of HO-1 inhibited by high glucose (HG) in zebrafish were confirmed for the first time via mapping the glucose-induced fluctuations of CO levels. Thus, we anticipate that probe NIR-CO not only can serve as a powerful tool to investigate the detailed biological functions of CO in the pathophysiological processes, but also possesses potential applications of in situ monitoring HO-1 activity in the complex biological systems.

Cell-selective imaging of some biological species is significant for the diseases research of a specific tissue or organ. Peroxynitrite (ONOO−) as a kind of reactive nitrogen species (RNS), plays extremely important roles in diverse physiological and pathological processes. Developing cell-specific fluorescent probes for tracing ONOO− in living systems remains a great challenge due to the complexity of internal environment and high autofluorescence. In this work, we developed a galactose-appended hepatoma-specific fluorescent probe Gal-NHP with hydroxynaphthalimide as the fluorophore and hydroquinone moiety as the responsive receptor for sensitively detecting endogenous ONOO− in live HepG2 cells. Probe Gal-NHP could selectively trace ONOO− without interference from other species such as HOCl and H2O2. In addition, the introduction of galactose enhanced the water solubility of this probe, and Gal-NHP could respond quickly to ONOO− in aqueous solution. The quantitative experiment showed the excellent sensitivity of this probe with a good linear relationship. Above all, fluorescence imaging results displayed it possessed excellent hepatoma-specific ability and could successfully detect endogenous ONOO− of hepatoma cells in real time. Thus, this newly developed probe would benefit to reveal the roles of ONOO− in hepatoma cells.

In this work, taking full advantage of the intramolecular charge transfer (ICT) mechanism, a hydroxynaphthalimide-based ratiometric two-photon fluorescent probe RTP-PN was synthesized to detect ONOO−. Probe RTP-PN could accurately detect ONOO− in the range of 1.4 nM-1.4 μM with the detection limit of 1.4 nM by a ratiometric fluorescence spectroscopy method. Additionally, probe RTP-PN exhibited an ultrafast response for ONOO− than other various species including H2O2 and ClO−. Finally, probe RTP-PN was successfully adopted to detect intracellular ONOO− by the two-photon excitation microscopy.

A water-soluble fluorescent probe for monitoring thiophenols based on a GFP-type TPC-OH fluorophore and a 2,4-dinitrophenyl ether recognition unit was designed. This probe possessed remarkable sensitivity and specificity toward thiophenols in an almost pure aqueous solution, and also showed good interference immunity to other related analytes including aliphatic mercaptans. Meanwhile, the probe displayed a prominent linear correlation between the thiophenol concentrations in the range of 0 to 20 μM and the fluorescence intensities at 492 nm, and the detection limit was as low as 33 nM. More strikingly, probe 1 was employed to visualize thiophenol in both living cells and zebrafish, which further demonstrated that probe 1 was a powerful practical tool in monitoring thiophenols in living systems.

Peroxynitrite (ONOO−) is a reactive and short-lived biological oxidant endogenously generated in biosystems, and its excessive production is related to various diseases. However, the functional mechanisms of ONOO− are not fully understood. Here, we present a novel ratiometric fluorescent probe CPD-ratio for the accurate detection of ONOO− under single wavelength excitation. This study showed that the probe CPD-ratio can achieve the ratiometric detection of ONOO− with rapid response, and it possessed excellent selectivity and sensitivity (detection limit was calculated to be 47 nM). These properties and its non-toxicity demonstrated that probe CPD-ratio could be potentially employed to accurately monitor ONOO− levels in biological systems. We have thoroughly demonstrated the utility of the probe CPD-ratio for ratiometric bioimaging, because it has been effectively used to trace the exogenous and endogenous ONOO− in live cells.

The detection of ionic mercury (Hg2+) is very important because it is a highly toxic environmental pollutant that could cause serious diseases and threaten human health. Herein, we designed a new carbonothioate-based far-red fluorescent probe, CBRB, with a seminaphthorhodafluor dye as the fluorophore for the detection of Hg2+. The CBRB probe by itself exhibited very weak fluorescence due to the enhanced photo-induced electron transfer (PET) effect and inhibited the intramolecular charge transfer (ICT) process caused by the carbonothioate moiety. Upon addition of Hg2+, a tremendous fluorescence enhancement was achieved, attributed to the removal of the carbonothioate group via a specific mercury-promoted desulfurization reaction. Moreover, the probe displayed a large Stokes shift (about 105 nm) and was used to quantitatively measure the concentration of Hg2+ for concentrations ranging from 0 to 1 μM (DL = 3.6 nM). In addition, CBRB in our experiments responded exclusively to Hg2+, even in the presence of high concentrations other ions. Gratifyingly, this probe was successfully used to monitor Hg2+ in environmental water samples and to image Hg2+ in living cells as well as in zebrafish.

A novel pH-sensitive fluorescent probe has been designed and synthesized for sensing intracellular pH. This probe showed excellent water solubility, it was sensitive toward the pH range from 4 to 12, and it was especially sensitive in alkaline environments. During the pH changes from acidic to alkaline environments, the color of the solution turned from yellow to purple, thus the difference in color can be used to distinguish between acidic and alkaline systems. The other major features of probe pH-DCN including high selectivity, low toxicity, good reversibility and stability allowed pH-DCN to visualize fluctuations of the pH in live cells. Moreover, probe pH-DCN has successfully discriminated cancer cells from normal cells by monitoring their different intracellular pH levels.

Graphene oxide (GO) has been extensively used in various critical fields such as biomedicine, while its antibacterial properties and potential toxicities raised serious concerns in recent years. The impacts of GO on the intestinal microbiota and associated immune responses in the host are still ambiguous. In this study, we investigated the effects of GO chronic exposure (25 days) on the composition of the intestinal microbiota and immune response in female & male zebrafish at different concentrations (0.05, 0.5, and 5 mg L−1). Results demonstrated that the diversity and richness of the bacterial community at the phylum and genus levels significantly differed in the presence of GO between female and male zebrafish. The in vitro assay verified the effect of acute toxicity of GO on the survival ability of bacterial strains isolated from zebrafish intestines, albeit no changes in the bacterial metabolic functions were observed. Further, exposure to GO significantly altered the length and width of villi in the anterior intestines, caused abnormalities of the ultra-micro structure, and increased the number of inflammation-related cells detected by transmission electron microscopy (TEM). Moreover, the elevated expression levels of crucial pro-inflammatory genes, such as tnf-α, ifn-γ, nf-κb, tlr-5, il-1β, and il-8, were significantly induced, while the expression levels of anti-inflammatory genes, such as il-4 and il-13, were inhibited, especially in male zebrafish. Taken all together, chronic exposure to GO disturbed the diversity and richness of intestinal microbes, increased the pathogenic bacterial community in zebrafish, induced damage to the gut tissues, and activated the inflammation response. These findings provided new insights into GO effects on the inflammation and intestinal microbiota in the host, which is closely linked with metabolisms and physiological activities in biological systems.

Porous conjugated polymers offer enormous potential for energy storage because of the combined features of pores and extended π-conjugated structures. However, the drawbacks such as low pore volumes and insolubilities of micro- and mesoporous conjugated polymers restrict the loading of electroactive materials and thus energy storage performance. Herein, we report the synthesis of iron-doped macroporous conjugated polymers for hosting sulfur as the cathode of high-performance lithium–sulfur (Li–S) batteries. The macroporous conjugated polymers are synthesized via in situ growth of poly(3-hexylthiophene) (P3HT) from reduced graphene oxide (RGO) sheets, followed by gelation of the composite (RGO-g-P3HT) in p-xylene and freeze-drying. The network structures of the macroporous materials can be readily tuned by controlling the chain length of P3HT grafted to RGO sheets. The large pore volumes of the macroporous RGO-g-P3HT materials (ca. 34 cm3 g–1) make them excellent frameworks for hosting sulfur as cathodes o...

In this work, a simple dichlororesorufin-based colorimetric and fluorescent probe R-Hg with the recognition receptor of carbonothioate was designed, synthesized, and exploited to determine mercury ions in aqueous solution and living cells as well as in zebrafish. After a series of analytical tests, probe R-Hg showed some excellent characteristics, such as ultrasensitivity, high selectivity, and good water solubility. The probe solution exhibited a very large fluorescence enhancement (about 150-fold) upon addition of Hg2+. Additionally, probe R-Hg exhibited excellent sensitivity, which could quantificationally detect Hg2+ at the nanomolar level, and the detection limit was 0.49 nM. Moreover, probe R-Hg could be used as a “naked-eye” probe for monitoring Hg2+, because the color of its solution transformed remarkably from yellow into pink with the participation of Hg2+. Importantly, probe R-Hg has potential application value and has been successfully applied to the determination of Hg2+ in practical water sa...

Nanofluidic ion transport through van der Waals heterostructures, composed of two or more types of reconstructed 2D nanomaterials, gives rise to fascinating opportunities for light-energy harvesting, due to coupling between the optoelectronic properties of the layered constituents and ion transport in between the atomic layers. Here, a photoinduced active ion transport phenomenon through transition metal dichalcogenides (TMDs)-based van-der-Waals-like multilayer heterostructures is reported for harnessing ionic power from equilibrium electrolyte solution. The binary heterostructure comprises sequentially stacked 2D-WS2 and 2D-MoS2 multilayers with sub-1 nm interlayer spacing. Upon visible-light illumination, a net ionic flow is initiated through the Janus membrane, suggesting a directional cationic transport from WS2 to MoS2 part. The transport mechanism is explained in terms of a photovoltaic effect due to type II band alignment of WS2 /MoS2 heterostructures. The driving mechanism can be generally applied to a variety of heterogeneous TMD membranes with type II semiconductor heterojunctions. In equilibrium ionic solutions, the maximum ionic photoresponse approaches ≈21 µA cm-2 and ≈45 mV under one sun equivalent excitation. Under optimized conditions, the harvested power density reaches 2 mW m-2 . The proof-of-concept demonstration of photonic-to-ionic power generation within angstrom-scale confinement anticipates potential for light-controlled ionic circuits, artificial photosynthesis, and biomimetic energy conversion.

Microplastics contamination is one of the leading environmental catastrophes for the marine ecosystem, but the molecular toxicity mechanism of those microplastics remains elusive. This study aims to determine the acute and chronic toxicity after exposure to polystyrene microplastics in brine shrimp with various concentrations. Our results demonstrated that acute exposure to polystyrene microplastics induced no significant effects on the survival of brine shrimp. Interestingly, the concentration-dependent increase in both bioaccumulation and the generation of reactive oxygen species (ROS) was observed after acute and chronic exposure. Moreover, the histopathology analysis revealed the deformation of epithelial cells in the midgut region after both acute exposures at 100 mg/L and chronic exposure at 1 mg/L to polystyrene microplastics. To elucidate the underlying mechanisms of microplastics-mediated toxicity, the transcriptome analysis was performed after chronic exposure, and the result showed 721 differentially expressed genes (DEGs) associated with 156 known KEGG pathways. 292 DEGs genes were significantly upregulated and 429 genes were significantly downregulated. The transcriptome analysis further revealed the DEGs related pathways. Taken together, this study not only highlighted the negative effects but also provided detailed sequencing data from transcriptome profiling to enhance our understanding of the molecular toxicity of polystyrene microplastics in brine shrimp.

Currently, microplastics (MPs) attracted increased attention for their ubiquity and toxic properties. In this study, marine medaka was used to explore the individual and combined toxicity of heavy metals (HMs) and MPs on intestinal bacteria and gonadal development. After exposure to environmentally relevant concentrations of MPs and HMs, significant alterations of intestinal microbiota were found. The MPs treatment reduced the diversity and abundance of intestinal microbiota, while the HMs and MPs-HMs treatments increased them, which were confirmed by the abundance changes of Proteobacteria. According to the KEGG analysis, the metabolism and environmental information processing (EIP) pathways in the microbial community were significantly affected. This study showed that the MPs-HMs treatment caused a higher pollution load on the gut of the marine medaka, and triggered more significant changes of specific bacterial species and gut function in the males. However, during the gonadal development, HMs and MPs-HMs treatments resulted in empty follicles (EF) and follicular atresia (FA), and altered the gene expression levels related to hypothalamic-pituitary-gonadal (HPG) axis. In short, this study demonstrated that the reproductive disturbance was mainly due to HMs, but the combination of MPs and HMs did not strengthen the risk to the gonad development of the marine medaka.

Phthalate esters (PAEs) pose prominent ecological risks owing to their multiplex toxicity potentials and ubiquitous detection in the environment. Therefore, this study aims to prioritize the individual and mixtures of six PAEs based on their toxicological implications using in vitro and vivo models exposed at environmentally relevant concentrations. Results were further confirmed using in silico Combination index (CI) and Independent action (IA), and molecular docking models. Among PAEs, DEHP revealed prominent in vitro/vivo toxicity followed by DEP, DBP, and DMP. Importantly, binary mixtures particularly C2-C6 and C11-C15 exhibited greater developmental toxicity, apoptosis, and perturbed the HPG pathway. The CI and IA models forecasted antagonistic and additive effects at Fa = 0.5 and Fa = 0.9 using in vitro Acinetobacter sp. Tox2. Conversely, in zebrafish, the IA model predicted mixture effects in the following order: additive > synergistic > antagonistic on the regulation of the HPG pathway, which was consistent with experimental results from Acridine Orange (AO) staining and apoptosis gene expression. Molecular docking for estrogen receptors (ERα, ERβ) revealed the highest binding energy scores for DEHP, compared to other PAEs. In short, our findings confirm that individual and mixtures of PAEs behave as xenoestrogens in the freshwater ecosystem with DEHP as a priority compound.

Graphene quantum dots (GQDs) are widely used for biomedical applications. Previously, the low-level toxicity of GQDs in vivo and in vitro has been elucidated, but the underlying molecular mechanisms remained largely unknown. Here, we employed the Illumina high-throughput RNA-sequencing to explore the whole-transcriptome profiling of zebrafish larvae after exposure to GQDs. Comparative transcriptome analysis identified 2116 differentially expressed genes between GQDs exposed groups and control. Functional classification demonstrated that a large proportion of genes involved in acute inflammatory responses and detoxifying process were significantly up-regulated by GQDs. The inferred gene regulatory network suggested that activator protein 1 (AP-1) was the early-response transcription factor in the linkage of a cascade of downstream (pro-) inflammatory signals with the apoptosis signals. Moreover, hierarchical signaling threshold determined the high sensitivity of complement system in zebrafish when exposed to the sublethal dose of GQDs. Further, 35 candidate genes from various signaling pathways were further validated by qPCR after exposure to 25, 50, and 100 μg/mL of GQDs. Taken together, our study provided a valuable insight into the molecular mechanisms of potential bleeding risks and detoxifying processes in response to GQDs exposure, thereby establishing a mechanistic basis for the biosafety evaluation of GQDs.

Developing highly specific and ultrasensitive techniques for monitoring hypochlorous acid (HOCl) in the environment and living systems is very important to guarantee its safe use and disclose its diverse biological functions. We herein presented a simple water-soluble lysosome-targeted fluorescent probe TCRH for the detection of HOCl. Probe TCRH could sensitively monitor HOCl at the nanomolar levels with the detection limit of 0.12 nM. Additionally, probe TCRH with the response unit of thiocarbamate could selectively detect HOCl over other various analytes. Furthermore, probe TCRH showed an ultrafast response for HOCl (

In recent years, targeting drugs made by physical loading or chemical bonding of drugs on small molecular carriers have shown a very wide application prospect in the field of tumor and cancer treatment. How to achieve the release of drugs in cancer cells has become the core of this research. One of the most important bases for drug localization is to use the difference of small molecular biothiol concentration between cancer cells and normal cells. Details of the changes of biothiol levels in the growth and reproduction of cancer cells are still poorly understood, and the main reason is the lack of sensitive real-time imaging tools for biothiols in cancer cells. In this work, we reasonably designed and synthesized the combination of 4-hydroxy-1,8-naphthalimide and NBD-Cl as a concise fluorescent probe HN-NBD for imaging biothiols in live cells and zebrafish. In addition, due to the advantages of HN-NBD design, it is sufficiently sensitive to biothiols, and further imaging can distinguish cancer cells from normal cells. Probe HN-NBD would be of great significance to biomedical researchers for the study of biothiol-related diseases, the screening of new anticancer drugs, and the early diagnosis and treatment of cancers.

In this paper we present a Superjunction IGBT (Super-IGBT) based upon Deep Trench (DT) Superjunciton technology to cope with high current density, smaller chip size and low switch losses. The current density of Super-IGBT is 550A/cm2(CP test:20A@1.8V), almost close to Si-IGBT limit. Moreover, under the same switch condition, Super-IGBT show 54% lower turn-on loss, 15% lower turn-off loss and 60% chip size shrink compared with the 650V FS-IGBT. Super-IGBT is favorable for high power and high frequency applications.

Exploiting specific and sensitive techniques for tracking peroxynitrite (ONOO−) in the biological systems is of great significance to understand its diverse pathophysiology. Herein, we have constructed a simple, 4-hydroxynaphthalimide-derived two-photon fluorescent probe TPHQ for imaging ONOO− in live cells. Probe TPHQ with the recognition receptor of hydroquinone moiety exhibited excellent selectivity towards ONOO− over various bio-related analytes including H2O2 and OCl−. Additionally, probe TPHQ could rapidly monitor ONOO− with high sensitivity (DL = 16 nM). With probe TPHQ, the fluctuations of ONOO− levels in live cells were successfully tracked by the one-photon and two-photon fluorescence microscopy.

Highly specific and ultrasensitive fluorescent probes for tracking the intracellular native hypochlorous acid (HOCl) levels are urgently needed owing to its important molecular functions in the biological systems. In this contribution, a simple thiocarbamate-caged 7-hydroxycoumarin (TCHC) was developed as fluorescent probe for monitoring HOCl in live cells. Probe TCHC exhibited preeminent specificity towards HOCl over other various bioactive substances. Importantly, probe TCHC could sensitively detect HOCl in the range of 0–175 pM with the detection limit of 17 pM, which was attributed to the multiple fluorescence sensing mechanisms including photo-induced electron transfer (PET), intramolecular charge transfer (ICT), and the chlorination. Furthermore, probe TCHC displayed an instant response towards HOCl (

Human embryonic kidney 293T cells (HEK293T cells) before and after treatment with silver nanoparticles (AgNPs) were measured using advanced atomic force microscopy (AFM) force measurement technique, and the biomechanical property of cells was analyzed using a theoretical model. The biomechanical results showed that the factor of viscosity of untreated HEK293T cells reduced from 0.65 to 0.40 for cells exposure to 40 μg/mL of AgNPs. Comet assay indicated that significant DNA damage occurred in the treated cells, measured as tail DNA% and tail moment. Furthermore, gene expression analysis showed that for the cells treated with 40 μg/mL of AgNPs, the antiapoptosis genes Bcl2-t and Bclw were, respectively, downregulated to 0.65- and 0.66-fold of control, and that the proapoptosis gene Bid was upregulated to 1.55-fold of control, which indicates that apoptosis occurred in cells exposed to AgNPs. Interestingly, excellent negative correlations were found between the factor of viscosity and tail DNA%, and tail moment, which suggest that the biomechanical property can be correlated with genotoxicity of nanoparticles on the cells. Based on the above results, we conclude that (1) AgNPs can lead to biomechanical changes in HEK293T cells, concomitantly with biological changes including cell viability, DNA damage, and cell apoptosis; (2) the factor of viscosity can be exploited as a promising label-free biomechanical marker to assess the nanotoxicity of nanoparticles on the cells; and (3) the combination of AFM-based mechanical technique with conventional biological methods can provide more comprehensive understanding of the nanotoxicity of nanoparticles than merely by using the biological techniques.

The development of highly specific and ultrasensitive fluorescent probes for tracking basal mitochondrial hypochlorite is very important to unravel its diverse cellular functions in the mitochondria of living cells. In this paper, we have developed a water-soluble, mitochondria-targeted near-infrared fluorescent probe NB-OCl for selectively measuring OCl- in the presence of higher concentration (500 μM) other biologically important substances. Surprisingly, the obtained results demonstrated that probe NB-OCl could sensitively determine OCl- in the range of 0-200 pM with the detection limit of 10.8 pM. To the best of our knowledge, NB-OCl is the first fluorescent probe for the specific determination of OCl- at the picomolar level. Moreover, probe NB-OCl exhibits a fast response for OCl- (< 5 s), which would be in favor of tracking the highly reactive and short-lived OCl- in the living systems. The preeminent recognition properties of probe NB-OCl enable its applications in the monitoring of basal OCl- and the fluctuations of endogenous/exogenous OCl- levels in the mitochondria of living cells.

Peroxynitrite (ONOO − ) is involved in various physiological and pathological processes. However the detailed mechanisms of ONOO − in the biological systems remain unclear, probably due to the lack of specific and sensitive methods for detecting ONOO − in living cells. Herein, based on the intramolecular charge transfer (ICT) mechanism, we have developed a highly specific and ultrasensitive ratiometric far-red fluorescent probe RFR-PN for monitoring ONOO − in living cells. Experimental results demonstrated probe RFR-PN possesses high specificity toward ONOO − than other various bioactive molecules. Probe RFR-PN could quantitatively and sensitively detect ONOO − with the detection limit of 0.9 nM by the ratiometric fluorescence method. Surprisingly, the fast response of probe RFR-PN for ONOO − ( − in the living systems. Moreover, probe RFR-PN was successfully applied to the fluorescence imaging of endogenous ONOO − in living cells.

The development of sensitive methods for imaging endogenous peroxynitrite (ONOO − ) in the mitochondria of living cells is very important to disclose its diverse physiological and pathological functions. In this paper, we have described a simple, mitochondria-targeted far-red fluorescent probe Mito-PN for selectively detecting ONOO − even though in the presence of higher concentration (1 mM) other biologically important substances. The experimental results indicated that probe Mito-PN could quantitatively determine ONOO − in the range of 0.5–8 μM with the detection limit of 17 nM. In addition, probe Mito-PN exhibits a fast response for ONOO − ( − in the biological systems. The excellent sensing properties of probe Mito-PN enable its applications in the tracking of the fluctuations of endogenous ONOO − levels in the mitochondria of living cells.

Salinity gradient energy, as a type of blue energy, is a promising sustainable energy source. Its energy conversion efficiency is significantly determined by the selective membranes. Recently, nanofluidic membrane made by two-dimensional (2D) nanomaterials (e.g., graphene) with densely packed nanochannels has been considered as a high-efficient membrane in the osmotic power generation research field. Herein, the graphene oxide-cellulose acetate (GO–CA) heterogeneous membrane was assembled by combining a porous CA membrane and a layered GO membrane, the combination of 2D nanochannels and 3D porous structures make it show high surface-charge-governed property and excellent ion transport stability, resulting in an efficient osmotic power harvesting. A power density of about 0.13 W/m2 is achieved for the sea–river mimicking system and up to 0.55 W/m2 at a 500-fold salinity gradient. With different functions, the CA and GO membranes served as ion storage layer and ion selection layer, respectively. The GO–CA heterogeneous membrane open a promising avenue for fabrication of porous and layered platform for wide potential applications, such as sustainable power generation, water purification, and seawater desalination.

To identify conveniently multiphase flow regimes in subsea pipeline-risers, we study in this paper experimentally two-phase flows in a 1657 m long pipeline with an S-shaped riser to simulate field experiment, within a wide range of gas and liquid velocities. Three flow regimes, namely severe slugging, transitional flows, and stable flows, are analyzed based on three differential pressure and one pressure signals at the top of the riser; comparatively speaking, the positions of these signals in the experimental system are similar to those of the sea level signals in industrial fields, which are easy and less expensive to obtain. The obtained signals are decomposed into six scales via a multi-scale wavelet analysis, and further four statistical parameters on each scale are extracted, including mean values, standard deviations, ranges, and mean values of absolute. We compared the effects of six SVM classifiers with different kernel functions on the recognition rate of flow regimes, and it is found the recognition rates of SVM classifier with quadratic and cubic kernel functions are the highest. Further, the principal component analysis is employed to reduce the dimension of statistical parameters and it indicates that the recognition rate tends to increase with the rising number of principal components from 1 to 6, and it remains constant if the principal component number is further increased. Moreover, The results suggest that the recognition rate obtained from the pressure difference between the top of the riser and the separator peaks, and then it comes that from the pressure signal at the top of the riser, and that for the pressure difference signal at the top of the riser is the least satisfying one. As for the optimal differential pressure signals between the top of the riser and the separator, the results show that the recognition rate increases rapidly from 70.2% to 90.4% when the sample duration rising from 2.3 s to 18.6 s, and when the sample duration exceeds 74.4 s, the recognition rate exceeds 92.9% and remains unchanged.

Here, we describe an in situ approach for growing polyepoxides from the surfaces of graphene oxide (GO) using a surface-initiated polymerization reaction. The polymerization methodology is facile and general as a broad range of epoxides carrying various functional groups have been successfully polymerized by simply adding GO powders in the epoxide monomers. The resultant polyepoxide grafted GO are found to show enhanced dispersibility in various common solvents and to exhibit increased d-spacing between the basal planes. In particular, grafting poly(2,3-epoxy-1-propanol) (PEP) to GO results in a composite (i.e., GO-g-PEP) that is dispersible in water and miscible with polyether block amide, i.e., Pebax MH 1657. Preliminary studies have indicated the membranes prepared using Pebax/GO-g-PEP composites exhibit enhanced CO2 permeabilities and selectivities in comparison to H2, O2, or N2. The excellent performance in gas separation is attributed to the layered structure of the GO-g-PEP sheets with enlarged d-s...

Hypochlorous acid (HOCl) has received special attention by virtue of its pivotal antimicrobial nature, and the appropriate amount of HOCl is beneficial to innate immunity of host to cope with microbial invasion. However, the uncontrollable accumulation of HOCl is implicated in many human diseases and even cancers. Thus, to determine its deeper biological functions, it is significantly important to specifically monitor intracellular HOCl in biosystems. Herein, we rationally designed a simple fluorescent probe

Layered graphene oxide membranes (GOMs) offer a unique platform for precise sieving of small ions and molecules due to controlled sub-nanometer-wide interlayer distance and versatile surface chemistry. Pristine and chemically modified GOMs effectively block organic dyes and nanoparticles, but fail to exclude smaller ions with hydrated diameters less than 9 A. Toward sieving of small inorganic salt ions, a number of strategies are proposed by reducing the interlayer spacing down to merely several angstroms. However, one critical challenge for such compressed GOMs is the extremely low water flux (

Biothiols such as cysteine (Cys), homocysteine (Hcy), glutathione (GSH) and hydrogen sulfide (H2S) are widely found in mammalian cells. They are closely related to the production and metabolic pathways and play very important roles in physiological and pathological activities. Therefore, the quantitative detection of these biothiols is of great significance. Although many fluorescent probes have been successfully used to track biothiols in biological samples, the fluorescence method for simultaneously detecting these biothiols using separated fluorescence emission channels under single wavelength excitation is still immature. In this work, we prepared the conjugate of seminaphthorhodafluor (SNARF) dye and 7-nitro-1,2,3-benzoxadiazole (NBD) using as a simple long-wavelength fluorescent probe SNARF-NBD for specific detection of biothiols. Cys/Hcy and GSH/H2S were identified by two separated fluorescence emission channels under single wavelength excitation, which showed good selectivity and sensitivity. In addition, SNARF-NBD has low cytotoxicity and shows good imaging ability in living cells and zebrafish.

Peroxynitrite (ONOO-) has been proven to participate in various physiological and pathological processes, and may also be a contributing factor in many diseases. In view of this, there is a need to develop detection tools for unambiguously tracking a small amount of endogenous ONOO- to reveal its exact mechanisms. In this paper, a colorimetric and red-emitting fluorescent probe Red-PN, based on a rhodamine-type fluorophore and hydrazide reactive site is described. The probe Red-PN possesses the advantages of rapid response (within 5 s), visual color change (from colorless to pink), preeminent sensitivity (detection limit = 4.3 nM) and selectivity. Because of these outstanding performances, it was possible to accurately detect endogenous ONOO-. It was encouraging that the probe Red-PN could be used effectively for tracking the relatively low levels of endogenous and exogenous ONOO- in living cells and zebrafish. Thus, it is envisioned that the probe Red-PN would have promising prospects in applications for imaging ONOO- in a variety of biological settings.

Layered graphene oxide membranes (GOM) with densely packed sub-nanometer-wide lamellar channels show exceptional ionic and molecular transport properties. Mass and charge transport in existing materials follows their concentration gradient, whereas attaining anti-gradient transport, also called active transport, remains a great challenge. Here, we demonstrate a coupled photon-electron-ion transport phenomenon through the GOM. Upon asymmetric light illumination, cations are able to move thermodynamically uphill over a broad range of concentrations, at rates much faster than that via simple diffusion. We propose, as a plausible mechanism, that light irradiation reduces the local electric potential on the GOM following a carrier diffusion mechanism. When the illumination is applied to an off-center position, an electric potential difference is built that can drive the transport of ionic species. We further develop photonic ion switches, photonic ion diodes, and photonic ion transistors as the fundamental elements for active ion sieving and artificial photosynthesis on synthetic nanofluidic circuits., Ionic transport through subnanometer-sized channels in 2D material-based membranes can be exploited for energy and separation applications. Here the authors demonstrate the visible light activation of an ultrafast ionic flux against a concentration gradient in graphene oxide membranes.

Mercury, as a highly toxic heavy metal, can cause very serious harm to human health and even death in severe cases. Therefore, we synthesized a novel ratiometric fluorescent probe for detecting mercury ions, with mercaptoethanol as the recognition receptor. Probe CMER could determine mercury ions in 0–1.6 μM and the detection limit is 7.6 nM. Moreover, CMER manifested a fast response for Hg2+ (within 5 s) and simultaneously observed that the color changed from light yellow to orange by naked eye. In addition to these preeminent spectral properties, the probe also had satisfactory bioimaging results in RAW 264.7 macrophage cells and zebrafish.

Aerobic composting is an effective way to realize recycling of organic solid wastes. It is not only convenient for operation and management, but also can convert waste into organic fertilizer. However during the composting process, the nitrogen in the heap exists in the form of organic nitrogen, ammonium nitrogen, nitrate nitrogen and other forms and is transformed into each other. It is also a potential source of ammonia (NH3) and nitrous oxide (N2O), and it is closely related to the environmental problems such as haze pollution and greenhouse effect. Combining with the researches of domestic and foreign scholars, this paper summarizes the form transformation of nitrogen elements, the emission mechanism of NH3 and N2O, and the adjustment and control measures in the aerobic composting process of the organic solid wastes, and it prospects the research direction for aerobic composting of the organic solid wastes.

Hypobromous acid is an important reactive oxygen species (ROS), which is involved in operating various cellular functions. However, the abnormal production of HOBr can induce the generation of a variety of diseases. Although fluorescence probes are huge contributor to our understanding of the biological roles of HOBr, relatively few probes have been used to detect HOBr. Hence, we constructed a ratiometric fluorescent probe Ratio-HOBr with high selectivity to sensitively monitor HOBr. Probe Ratio-HOBr exhibited quick response (

Landfill leachate has become an important source of environmental pollution in past decades, due to the increase of waste volume. Acute toxic and genotoxic hazards to organisms can be caused by landfill leachate. Thus, how to efficiently recover water from landfill leachate and effectively eliminate combined toxicity of landfill leachate are the most pressing issues in waste management. In this study, EDTA-Na2Zn as draw solution (DS) was used to remove the toxicity of membrane bioreactor-treated landfill leachate (MBR-treated landfill leachate) in forward osmosis (FO) process, and nanofiltration (NF) was designed for recovering the diluted DS. Zebrafish and human cells were used for toxicity assay after the novel wastewater treatment process using EDTA-Na2Zn as DS. Results showed that the water recovery rate of MBR-treated landfill leachate (M-LL) in FO membrane system could achieve 66.5% and 71.2% in the PRO and FO mode respectively, and the diluted DS could be efficiently recovered by NF. Toxicity tests performed by using zebrafish and human cells showed that M-LL treated by EDTA-Na2Zn had no toxicity effect on zebrafish larvae and human cells, but it had very slight effect on zebrafish embryos. In conclusion, all results indicated that EDTA-Na2Zn as DS can effectively eliminate toxicity of landfill leachate and this method is economical and eco-friendly for treatment of different types of landfill leachate.

In order to prepare bio-nanocomposites with no-cytotoxicity, the rosin-based epoxy resin (MPAER) and castor oil-based polyurethane (COPU) were synthesized and carbon nanotubes (CNTs) was used to enhance the properties of curing MPAER/COPU materials. The curing reaction, dynamic mechanical and thermal properties of this system were characterized by FTIR, NMR, DMA, TG et al. The cytotoxicity of materials is evaluated for HeLa cells using a MTT cell-viability assay. The results showed that COPU can cure MPAER and CNTs can increase effectively the properties of MPAER/COPU nanocomposites. The Tg of MPAER/COPU/CNTs has the highest value when CNTs content is 0.4 wt%, which is 52.4 °C higher than the pure MPAER/COPU. Thermal stability of the nanocomposites is enhanced by the addition of CNTs, the initial decomposition temperature Td5 of the sample No. 0.4 has increased from 284.5 to 305.2 °C, which is 20.7 °C higher than No. 0. The impact strength of the No. 0.4 film is 15 kg cm higher than the pure resin system. The survival rate of HeLa cells to the products is greater than 90% within 48 and 72 h, which demonstrate that this material has excellent biocompatibility and no obvious cytotoxicity for HeLa cells, which may be used in the medical treatment.

It is very important to determine mercury owing to its complex biological poisonousness that could cause various physical diseases and even death. In this study, we designed a novel coumarin-based ratiometric fluorescent probe, CR-Hg, with DL-dithiothreitol moiety as the recognition receptor to detect mercury ions (Hg2+). CR-Hg could realize the quantitative detection of Hg2+ between 0 and 1.4 μM with low detection limit (1.6 nM). Furthermore, CR-Hg could react quickly with Hg2+ in a few seconds and accompanied by color changes from pale yellow to orange. In the end, the applications of CR-Hg in the water samples, living cells and zebrafish more deeply indicated that the probe could serve as a novel promising tool for revealing mercury distribution in the environment and organisms.

As one of the reactive oxygen species (ROS), hypochlorous acid (HOCl) plays a key role in the pathogenesis of a range of diseases. The detection of HOCl has been a hot research topic. Herein, this paper proposes a new conjugate of 4-hydroxy-1,8-naphthalimide and p-methylaminophenylether as fluorescent probe HNPE with simple synthesis and excellent performances to detect HOCl. The probe has a good linear relationship with HOCl (0–1 μM), and its detection limit is 6.56 nM. Moreover, this probe has good selectivity, which can distinguish HOCl from other common analytes. Importantly, the probe HNPE has some achievements in HOCl imaging of living cells and zebrafish. Hence, the probe HNPE is competent as a tool to visualize HOCl in biosystems.

In the appropriate Golgi stress response, adaptive repair will occur by changing or triggering the expression of related pathways. Furthermore, it also can inhibit the cytotoxicity of cells in the altered redox homeostasis. Elevated biosynthesis and transport of cysteine (Cys) will be induced to restore the abnormal redox state, and more evidences are needed to confirm this process in the Golgi stress response. Herein, we developed a novel Golgi-targetable Cys-specific fluorescent probe GT-Cys for sensitively detecting Cys generation during the Golgi stress response. In probe GT-Cys, thiobenzoate moiety was chosen as recognition group of Cys, and 4-CF3-7-aminoquinoline dye was selected as fluorophore and Golgi targetable unit. Probe GT-Cys can selectively and sensitively respond to Cys. Additionally, it has good targetable properties, facilitating the study of complicated stress response of Golgi apparatus. Importantly, the applications of probe GT-Cys in biological imaging showed that it is sensitive enough to basal Cys, especially to endogenous Cys during the Golgi stress response.

Iron plays an essential role in the chemical transformation of cells via the transition of multiple oxidation states of iron. Misregulation of iron may lead to the disorder of reactive oxygen species (ROS) catalyzed by iron, which is associated with diverse diseases. Therefore, the monitoring of labile iron in vivo is crucial for revealing its diverse functions in the biosystems. In this work, a novel “off-on” fluorescent probe NT-Fe was designed to detect ferrous ion (Fe2+) in both aqueous solutions and biological systems, based on the reduction of nitroxides to hydroxylamine. Probe NT-Fe manifested highly selective and sensitive detection (DL = 89 nM) of Fe2+. In addition, probe NT-Fe can detect Fe2+ within 50 s, which is conducive to real-time detection of labile iron in the biological system. Moreover, the intracellular Fe2+ can be tracked with probe NT-Fe in living cells effectively. Most of all, as far as we know, probe NT-Fe has been used for the first time to monitor Fe2+ in zebrafish.

CO-releasing molecule-2 (CORM-2), as a safe donor for releasing CO, has been widely adopted to disclose the physiopathological roles of CO and used as therapeutic drug replacing gaseous CO. The accurate determination of CORM-2 levels in biological systems is central for understanding its safe use as therapeutic agent and the cellular functions of CO. In this paper, a novel fluorescent probe CPD-NB was synthesized, which provided a safe and convenient way for detecting CORM-2 without the requirement of Pd2+ as an additional substrate. It featured a robust fluorescence response to CORM-2 with desirable sensitivity (the detection limit was as low as 4 nM), and showed high selectivity toward CORM-2 over other biologically relevant species. Moreover, with the low cytotoxicity of probe CPD-NB, the visualizations of CORM-2 changes in live cells and zebrafish were also achieved. Thus, we expected that probe CPD-NB could be as an ideal platform for safe and powerful imaging of CORM-2 in biological systems, and may thus promote the progress of CO-related research.

Hypobromous acid (HOBr) is profoundly implicated in many physiological and pathological conditions. In vivo, the production of HOBr is a double-edged sword for organisms. Appropriate amount of HOBr have effective antibacterial activity, however, abnormal production of HOBr can easily cause tissue damages. Unfortunately, the detailed cellular functions of HOBr are still unclear, which are mainly because highly specific and sensitive sensing of HOBr in living organism remains to be challenged. Based on that, a new n aphthalimide-derived 1-(2- a mino e thyl) p iperidine-containing highly selective fluorescent probe NAEP-HOBr for bioimaging endogenous HOBr was designed. Probe NAEP-HOBr possesses satisfactory sensitivity reflected in low detection limit (200 nM), pleasurable selectivity over others biological molecules, and rapid response for HOBr (∼1 min). Moreover, probe NAEP-HOBr is competent for tracking endogenous HOBr in living cells and zebrafish, which further provides an effective and powerful tool for tracking the fluctuations of endogenous HOBr in living organisms.

Developing a reliable tool for monitoring peroxynitrite (ONOO−) in the complex organisms is critical to uncover its detailed cellular functions in numerous physiological and pathological processes. Thus, a novel ratiometric fluorescent probe was reasonably designed for ONOO−, in which the rhodol-HBT conjugate dye was chosen as a fluorophore, and hydrazine moiety was adopted as recognition receptor of ONOO−. The probe exhibited outstanding sensitivity, specificity, and a fast response towards ONOO−. More importantly, the probe with a large emission shift (Δλem = 127 nm) has been proven to be capable of tracking ONOO− with high resolution in live cells and zebrafish. This work provides a simple and reliable tool for detecting and imaging ONOO− in the living systems, and thus we anticipate that the designed probe could be used as a powerful imaging tool in unraveling biological functions of ONOO−.

The unique feature of nacre-like 2D layered materials provides a facile, yet highly efficient way to modulate the transmembrane ion transport from two orthogonal transport directions, either vertical or horizontal. Recently, light-driven active transport of ionic species in synthetic nanofluidic systems attracts broad research interest. Herein, taking advantage of the photoelectric semiconducting properties of 2D transition metal dichalcogenides, the generation of a directional and greatly enhanced cationic flow through WS2 -based 2D nanofluidic membranes upon asymmetric visible light illumination is reported. Compared with graphene-based materials, the magnitude of the ionic photocurrent can be enhanced by tens of times, and its photo-responsiveness can be 2-3.5 times faster. This enhancement is explained by the coexistence of semiconducting and metallic WS2 nanosheets in the hybrid membrane that facilitates the asymmetric diffusion of photoexcited charge carriers on the channel wall, and the high ionic conductance due to the neat membrane structure. To further demonstrate its application, photonic ion switches, photonic ion diodes, and photonic ion transistors as the fundamental elements for light-controlled nanofluidic circuits are further developed. Exploring new possibilities in the family of liquid processable colloidal 2D materials provides a way toward high-performance light-harvesting nanofluidic systems for artificial photosynthesis and sunlight-driven desalination.

As a reactive nitrogen species (RNS), peroxynitrite (ONOO−) is known for its crucial functions in biological systems. Excessive formation of ONOO− is very closely related to the pathogenesis of a series of diseases, and thus, effective methods are needed for highly sensitive detection of ONOO−. Herein, a simple fluorescent probe RHHP-PN was proposed to detect ONOO−, and manifested obvious color changes from colorless to red in less than 10 s. Besides, it is not only suitable for quantitative detection of ONOO−, but also satisfactory in distinguishing ONOO− from other related species. What is particularly noteworthy is the fluorescence bioimaging for tracing endogenous and exogenous ONOO− in living cells and zebrafish. Therefore, probe RHHP-PN could be used as an imaging tool to visualize intracellular ONOO− in biological systems.

The accurate and sensitive determination of basal hypochlorous acid (HOCl) in the biosystems is critical for unraveling its various physiological and pathological functions. Additionally, recent studies have shown that cancer cells possess higher concentration HOCl than normal cells. However, related studies about the discrimation of tumor cells and tissues from normal cells and tissues by using a simple HOCl probe have seldom been reported. Herein, we presented a simple, water-soluble, two-photon long-wavelength fluorescent probe TPFR for detecting HOCl with outstanding selectivity over other potential interfering substances. The fluorescence titration experiments demonstrated that probe TPFR was capable of quantitatively detecting 0–500 nM HOCl (DL = 0.9 nM). Additionally, the rapid response (

High-performance flame-retardant materials are urgently needed to address outstanding issues that pertain to safety. Traditional flame retardants are toxic to the environment and/or lack the physical properties required for use in many contemporary applications. Here, we show that isocyanate-based polyimide (PI) foam, a flammable material, can exhibit unusually superior flame retardancy as well as other excellent properties, such as being lightweight and displaying high mechanical strength, by incorporating red phosphorus (RP)-hybridized graphene. The covalent bonds formed between the graphene platelets and the PI matrix provide the resultant PI foam with a specific Young’s modulus (83 kNm kg–1) that is comparable to or even higher than those displayed by state-of-the-art foams, including silica aerogels, polystyrene foams, and polyurethane foams. In addition, even a low content of the RP-hybridized graphene (2.2 wt %) results in an exceptionally higher limiting oxygen index (39.4) than those of tradition...