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Solar photocatalysis is the key to resolve many environmental challenges but is usually hard to achieve over a metal oxide semiconductor. Therefore, assembling π-conjugated molecules onto semiconductors becomes an efficient approach to solar conversion via ligand-to-metal charge transfer. Here, a rational design of ligands for titanium dioxide (TiO2) is presented to produce robust visible light photocatalysts. Three hydroxynaphthoic acids (HNAs) were selected as ligands by extending an extra benzene ring of salicylic acid (SA) at 3,4 or 4,5 or 5,6 positions. These ligands could regulate the performance of TiO2 in which 2-hydroxy-1-naphthoic acid (2H1NA) endows the best outcome. In detail, blue light-powered cooperative photocatalysis of 2H1NA-TiO2 with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO, 5 mol%) inaugurates the expeditious formation of imines by oxidation of amines with atmospheric oxygen (O2). Interestingly, the increase of the O2 pressure from 1 atm to 0.4 MPa promoted the selective oxidation of benzylamine but thereafter declined with a further boost to 0.6 MPa. Notably, an electron transfer between the oxidatively quenched 2H1NA-TiO2 and TEMPO is established, offering a new pathway for environmental applications. This work presents a strategy in designing cutting-edge visible light photocatalysts via altering semiconductors with surface ligands.

Ultrahigh charge separation was observed in Bi4O5I2/Bi5O7I two-dimensional (2D)/one-dimensional (1D) hierarchical structures (HSs) constructed by selective growth of 2D monocrystalline Bi4O5I2 nanoplates on the electron-accumulating (100) facet of 1D monocrystalline Bi5O7I nanobelts. In addition to the presence of type-II heterojunction between Bi4O5I2 and Bi5O7I elementary entities in 2D/1D HSs, the type-II (100)/(001) surface heterojunction in Bi5O7I nanobelt substrates was also confirmed by means of density functional theory (DFT) calculations and selective photoreduction/oxidation deposition experiments. The synergistic effect of two kinds of heterojunctions in Bi4O5I2/Bi5O7I 2D/1D HSs endowed them with ultrahigh charge carrier separation and transfer characteristics. In contrast with the control sample (BB40-C) constructed by growing Bi4O5I2 nanoplates on whole four sides of Bi5O7I nanobelts, Bi4O5I2/Bi5O7I 2D/1D HSs demonstrated significantly enhanced charge transfer between Bi5O7I nanobelt substrates and Bi4O5I2 nanoplates, owing to respective electron and hole accumulations on (100) and (001) facets of Bi5O7I substrates caused by (100)/(001) surface heterojunction. The enhanced separation behavior was successfully verified by steady/transient-state photoluminescence, electrochemical techniques, and photocatalytic degradation experiments. Based on the above effective charge separation of Bi4O5I2/Bi5O7I 2D/1D HSs as well as the routine advantages for 2D/1D HSs, such as the excellent charge transport in monocrystalline elementary entities, much higher specific surface area, and enhanced light absorption by multiple reflections, the optimal BB40 HSs demonstrated ultrahigh photocatalytic performance than the control samples, whose apparent rates for Rhodamine B [or tetracycline hydrochloride (TC)] degradation were 7.1 (2.9 for TC), 10.3 (4.7 for TC), and 2.2 (1.7 for TC) times those of pristine Bi5O7I nanobelts, Bi4O5I2 nanoplates, and BB40-C, respectively. It is hoped that this crystal facet selection during the heterostructure construction in this work could provide a new strategy or some enlightenment for the exploration of highly active 2D/1D HSs or other-dimensional heterostructure nanomaterials applied in the fields of photocatalysts, solar cells, sensors, and others.

Attaching π-conjugated molecules onto TiO2 can form surface complexes that could capture visible light. However, to make these TiO2 surface complexes durable, integrating 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) or its analogues as a redox mediator with photocatalysis is the key to constructing selective chemical transformations. Herein, sodium 6,7-dihydroxynaphthalene-2-sulfonate (DHNS) was obtained by extending the π-conjugated system of catechol by adding a benzene ring and a substituent sodium sulfonate (-SO3 - Na+ ). The DHNS-TiO2 showed the best photocatalytic activity towards the blue light-induced selective aerobic oxidation of benzylamine. Compared to TEMPO, 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl (4-amino-TEMPO) could rise above 70% in conversion of benzylamine over the DHNS-TiO2 photocatalyst. Eventually, a wide range of amines could be selectively oxidized into imines with atmospheric O2 by cooperative photocatalysis of DHNS-TiO2 with 4-amino-TEMPO. Notably, superoxide (O2 •- ) is crucial in coupling the photocatalytic cycle of DHNS-TiO2 and the redox cycle of 4-amino-TEMPO. This work underscores the design of surface ligands for semiconductors and the selection of a redox mediator in visible light photocatalysis for selective chemical transformations.

Aflatoxin B1 (AFB1) is one of the most toxic, mutagenic and carcinogenic mycotoxin, widely exists in contaminated food, grains and feedstuff products. In this study, a novel magnetic beads multicolor colorimetric immunoassay (MBMCIA) based on Au@Ag nanorods (Au@Ag NRs) is proposed to visual detect ultralow concentration of AFB1 with high-resolution by the naked-eye. To design the MBMCIA system, AFB1-BSA conjugates were first coated on the surface of magnetic beads (MBs), then alkaline phosphatase (ALP) as a bridge between immunoassay and color reaction was used for catalytic hydrolysis of ascorbic acid-phosphate to generate reductive ascorbic acid. Finally, the yielded ascorbic acid could reduce silver ions to grow a silver coating on the surface of gold nanorods to generate Au@Ag NRs, which leads to the bule-shifted longitudinal absorption peak of Au NRs, accompanying with a series of perceptible color change. Under the optimal conditions, the proposed MBMCIA exhibited good sensitivity and specificity for the detection of AFB1 with the detection limit as low as 5.7 pg/mL. Meanwhile, the MBMCIA was also applied for the analysis of AFB1 in spiked wheat samples, the obtained recoveries range from 99.1% to 104.3% with relative standard deviation (RSD) less than 7.05% were acceptable. The proposed MBMCIA integrates separated, enriched, anti-interference and signal read-out into one, which opens up a new avenue for an on-site visual food safety inspection or environmental monitoring.

Nb2O5 is a colourless metal oxide that is very promising in areas such as energy storage and optical glasses. These applications depend on the superior redox properties of Nb2O5 compared to those of other metal oxides, which in turn endow it with great potential in semiconductor photocatalysis. Herein, a hierarchical Nb2O5 was synthesized by the L-arginine-assisted hydrothermal method. Thereafter, visible light photocatalysis was bridged over hierarchical Nb2O5 with a common organic dye, namely alizarin red S (ARS), significantly renovating Nb2O5-based photocatalysis from ultraviolet (UV) into the green light region. The surface of hierarchical Nb2O5 was chemically modified with ARS to harvest 520 nm green light and facilitate the oxidation of organic sulfides with aerial O2. The O-atom transfer from O2 into sulfoxides with very high selectivity occurs via an intermediate of superoxide radical anions (O2˙−). Importantly, the electron transfer from activated ARS to sulfides is mediated by an electron transfer mediator, namely (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO), to deter the attack of quenched ARS by reactive oxygen species (ROS). This study represents the first foray of dye-semiconductor assemblies based on a semiconductor other than TiO2 for the selective aerobic oxidation, affirming the generality of cooperative photocatalysis and implying the great potential of hierarchical Nb2O5 in platforming the visible-light-induced selective transformation of organic molecules.

Nanoparticles are produced by chemical methods which are usually environmentally hazardous because of the use of various perilous chemicals and harsh reaction conditions. Bio-mediated synthesis using microbes has been proved to be a promising substitute for traditional methods to synthesize nanoparticles. Herein, based on the principles of biomimetic mineralization, a bio-mediated strategy was proposed to synthesize biocompatible barium carbonate nanoparticles (nBaCO3) in living yeast cells according to the intracellular biochemical reactions using tactfully the interaction of endogenous CO32− and exogenous Ba2+ under normal growth conditions of the yeast cells. The intracellular nBaCO3 are well-dispersed and the diameter of the nanoparticles is successfully controlled at about 5 nm under mild conditions. The bio-mediated strategy to obtain nanomaterials can be universally applied to biosynthesize other kinds of components with good biocompatibility. This biosynthesis route for barium carbonate nanoparticles mediated by the cells not only presents a green and facile design to synthesize well-tailored nanomaterials using a biomineralization-inspired strategy but may also lead to new insights for nanotechnology.

Iridium(III) porphycene complex was synthesized and structurally characterized for the first time. The introduction of the posttransition iridium(III) ion not only significantly enhances the absorption intensity at the end of visible region, but also displays efficient singlet oxygen quantum yield (76%), which is applicable for photodynamic therapy in living cells.

Inspired by biomineralization, the first synthesis of size-tunable calcium carbonates from nanoparticles (YC-CaCO3 NPs) to nano/microspheres (YC-CaCO3 N/MSs) with a porous structure was accomplished using a facile method under the mediation of the secretion from yeast cells (YCs). The biomolecules derived from the secretion of YCs were used as conditioning and stabilizing agents to control the biosynthesis of the YC-CaCO3 materials. The morphology and crystal forms of YC-CaCO3 materials can be affected by the biomolecules from the secretion of YCs. With increasing concentrations of biomolecules, the morphologies of the obtained CaCO3 materials changed from nanoparticles to nano/microspheres with a porous structure, while the crystal forms transformed from amorphous to calcite. Functional investigations showed that YC-CaCO3 NSs with a porous structure effectively acted as anticancer drug carriers with accurate and selective drug release in tumor tissue, which suggests that they have great potential to function as a therapeutic delivery system. These application features are mainly attributed to the satisfactory biocompatibility and biodegradability, high drug-loading capacity, and pH-dependent sustained drug release performance of the porous YC-CaCO3 NSs. The biomimetic synthesis strategy of YC-CaCO3 materials mediated by YC secretion not only helps to shed light on the biomineralization mechanism in organisms, but may also lead to a new means of biosynthesizing organic–inorganic nanocomposites.

BACKGROUND Acute liver injury (ALI) is an essential component of sepsis associated with poor outcomes. Octanoic acid (OA), a medium-chain fatty acid, has a protective effect on sepsis-induced organ damage, and autophagy is an adaptive response to sepsis. However, the underlying mechanism by which OA prevents ALI remains unknown. Therefore, we investigated whether OA-rich enteral nutrition (EN) prevented lipopolysaccharide (LPS)-induced ALI through the c-Jun N-terminal kinase (JNK)-dependent autophagy. METHODS Firstly, Sprague Dawley rats were randomly divided into four groups (sham, LPS, LPS + EN, and LPS + EN + OA) to detect the effect of OA-rich EN on LPS-induced ALI. Then, rats were randomly divided into five groups (sham, LPS, LPS + EN + OA, LPS + EN + OA + anisomycin (AN), and LPS + SP600125) to explore the mechanism by which OA-rich EN prevented ALI. EN and OA-rich EN were conducted through gastric tubes for 3 days. The liver protective effects were measured by liver histopathological changes, enzymes, inflammatory cytokines of serum and liver, the levels of autophagy, and JNK activity. RESULTS OA-rich EN inhibited JNK activity, up-regulated autophagy and prevented LPS-induced ALI. Inhibition of JNK activity conferred by SP promoted autophagy and prevented LPS-induced ALI. Moreover, the protective effect of autophagy and inhibition of JNK activity conferred by OA-rich EN on ALI was counteracted by AN. CONCLUSION OA-rich EN prevented LPS-induced ALI through JNK-dependent autophagy. This result suggested that OA-rich EN may be a therapeutic potential for ALI in patients with sepsis.

Rapid industrialization and urbanization have resulted in elevated concentrations of contaminants in the groundwaters and subsurface soils, posing a growing hazard to humans and ecosystems. The transformation of most contaminants is closely linked to the mineralogy of ferric (hydr)oxides. Sulfidation of ferric (hydr)oxides is one of the most significant biogeochemical reactions in the anoxic environments, causing reductive dissolution and recrystallization of ferric (hydr)oxides and further affecting the transformation of iron-associated contaminants. This paper provides a comprehensive review on the sulfidation process of ferric (hydr)oxides and the transformation of relevant contaminants. This review presents detailed reaction mechanisms between ferric (hydr)oxides and dissolved sulfide, and elucidates the factors (e.g. crystallinity of ferric (hydr)oxides, the ratio of sulfide concentration to the surface area concentration of ferric (hydr)oxides) that control the formation of surface associated Fe(II), iron sulfide minerals, as well as transformation of secondary minerals. Then, we summarized the transformation mechanisms of a variety of typical environmentally relevant contaminants existing in groundwater and subsurface soils, including heavy metals, metal(loid) oxyanions (arsenic, antimony, chromium), radionuclides (uranium, technetium), organic contaminants and phosphate/nitrate species. The general mechanisms of contaminant transformation involve a combination of release, reduction and re-adsorption/incorporation processes, the specific pathway of which is highly dependent on the properties of the contaminant itself and the extent of sulfidation. Moreover, the challenge of extending our knowledge towards in situ remediation, as well as further research needs are identified.

An AIEgen decorated porphyrin (TPETPyP) was easily obtained through a one-step reaction. The bulky TPE in TPETPyP greatly impeded the intermolecular π-π stacking of the porphyrin core, which significantly suppressed aggregation-caused quenching (ACQ) effect of TPETPyP in aqueous solution. The four pyridinium salts formed in TPETPyP also render the whole molecule water solubility, which eliminated its aggregation. TPETPyP exhibited 1O2 quantum yield as high as 0.85 in PBS. Moreover, it also showed high binding affinity to proteins, the major biotarget of 1O2. The high 1O2 quantum yield plus the great binding ability of TPETPyP toward proteins makes it a highly-efficient protein photocleaving agent. Protein electrophoresis experiments demonstrated that TPETPyP can photocleave BSA upon visible light irradiation, indicating that TPETPyP can act as a promising photosensitizer (PS) in PDT. The work here will provide a facile strategy to utilize AIEgens modified traditional PSs for photodynamic therapy (PDT).

Bi2S3/2D-Bi2WO6 composite materials which combined 2D-Bi2WO6 with Bi2S3 nanoparticles were prepared via ion exchange method. The mass ratio of Bi2S3 nanoparticle could be modulated by changing the quantity of thioacetamide (TAA). For Bi2S3/2D-Bi2WO6 composite materials, Bi2S3 nanoparticles dispersed on the surface of Bi2WO6 nanosheets. The photocatalytic activity was evaluated by photodegradation rhodamine B (RhB) under visible light. RhB was photodegraded nearly completely by BWS-2, while only 67% was photodegraded by Bi2WO6 nanosheet after 5 h' visible light irradiation. Based on the optical and electrochemical measurements, Bi2S3/2D-Bi2WO6 composite materials have prolonged carriers' lifetime, improved carriers' separation efficiency and decreased carriers' recombination efficiency. These results endow Bi2S3/2D-Bi2WO6 composite materials with high photocatalytic activities.

The application of nanoscale zero-valent iron (nZVI) for the degradation of contaminants has been extensively investigated, however, few studies have focused on degradation in high salinity environments. In this study, the ability of bare and carboxymethyl cellulose (CMC)-coated bimetallic Pd-nZVI particles to degrade 33′44′-tetrachlorobiphenyl in high saline water (SW) is examined with particular attention given to the effects of ethylenediaminetetraacetic acid (EDTA) on the rate of degradation. EDTA enhances the reactivity of Pd-nZVI in SW, with evidence provided to link this to the removal of the passivating layer. Additionally, a conceptual model is proposed which provides a quantitative description of the removal of these iron oxide layers in the presence of EDTA. An optimum EDTA to bare Pd-nZVI molar ratio of 0.1 exists, with insufficient EDTA unable to remove the passivating layer whilst excess EDTA results in Fe loss and enhanced agglomeration due to magnetic attraction of the bare Fe(0) particles. In contrast, CMC-coating of Pd-nZVI assemblages actually impedes degradation, despite the coated particles displaying a smaller average size compared to uncoated particles, with even the presence of EDTA in this case not significantly improving degradation. The reduced reactivity in the presence of CMC is primarily attributed to the effect of CMC on the association of Pd with nZVI particles. In particular, the presence of CMC reduced the total amount of Pd incorporated with the stabilized particles compared to the non-stabilized particles. Additionally, the presence of CMC results in less Pd present in its reactive zero-valent oxidation state.

Sulfidation of silver nanoparticles (Ag-NPs) readily occurs in both urban sewage systems and sulfur-rich natural environments with formation of silver sulfide nanoparticles (Ag2S-NPs). It is essential to understand the transformation and fate of Ag2S-NPs in order to fully evaluate environmental impact of Ag-NPs. The review focuses on the formation and transformation of Ag2S-NPs from both thermodynamic and kinetic perspectives, particularly (i) the formation mechanism of Ag2S in various environmental scenarios, (ii) redox transformation of Ag2S caused by oxidation of S(−II) and (iii) effects of environmental matrices on the formation and transformation processes. In most cases, sulfidation of Ag-NPs causes a dramatic decrease in their toxicity due to the extremely low solubility of Ag2S, potentially restraining their short-term environmental impact. However, the transformation of Ag2S-NPs with potential release of Ag+ and in situ formation of Ag0 and Ag0/Ag2S-NPs hetero-nanostructures may possibly increase the toxicity. Mechanistically-based kinetic modeling has been proposed here to quantitatively describe the rate and extent of the transformation of Ag2S-NPs, with such models of value, at least, in validating proposed transformation mechanisms of Ag2S-NPs and, at best, in predicting their transformation behaviors under realistic environmental conditions.

Thallium (Tl) often enters the environment via mineral exploitation and utilization. The main restriction of Tl removal is the interference of high concentrations of coexisting ions in wastewater, therefore, enhancing the selectivity for Tl is essential to its treatment. Magnetic Prussian blue particles (Fe3O4@PB), an ion-sieving material with an open structure, were synthesized through a “one-pot” method at room temperature for the highly selective removal of Tl+. The removal percentage of Tl+ was over 92% even when the concentration of coexisting ions (e.g. Zn2+, Cd2+, Cu2+, and Pb2+) were 10,000 times higher than the initial concentration of Tl+. The maximal experimental removal capacity was 528 mg Tl/g Fe3O4@PB, and the removal percentage remained steady at pH 3–10. The high selectivity of Fe3O4@PB for Tl+ is attributed to the fact that hydrated Tl+ has a smaller hydrated diameter and a lower hydration free energy than other coexisting ions, while the rapid adsorption kinetics of Tl+ results from the negative surface charge and the network of nanocapillaries of the Fe3O4@PB. Overall, a new low-cost material that is easy to synthesize and has superior Tl+ removal capacity with extremely high selectivity for Tl+ was obtained for effective magnetic removal of thallium from wastewater.

Sequential inter- and intramolecular [3 + 2] cycloadditions of azomethine ylides are developed for the one-pot and diastereoselective synthesis of highly condensed heterocyclic systems containing pyrrolidine and up to seven stereocenters. It has high synthetic efficiency and operational simplicity, and only water was generated as a byproduct.

Developing selective formation of sulfoxides by aerobic oxidation of sulfides over highly efficient visible-light photocatalysts is an essential but challenging task. Herein, a conjugated microporous polymer (CMP) photocatalyst with the desired linkage thiazolo[5,4‑d]thiazole (TzTz) is presented to undertake this task. Remarkably, a catalyst-free solvothermal process afforded TzTz-CMP-3 from tetra(4-formylphenyl)-benzene and dithiooxamide. The photocatalytic activity of TzTz-CMP-3 is demonstrated with the blue light-powered selective formation of sulfoxides by aerobic oxidation of sulfides. A wide range of sulfoxides can be effectively formed by oxidation of sulfides with excellent product selectivities (up to 99 %) over the TzTz-CMP-3 photocatalyst. The more symmetric π-conjugated aromatic ring of TzTz-CMP-3 endows it with more favorable activity than the less symmetric ones. This work underscores the symmetry of building blocks for CMPs for selective photocatalytic formation of valuable organic molecules.

Visible light photocatalysis could offer an eco-friendly alternative for selective transformation of organic molecules. Herein, a cooperative system is created with alizarin red S (ARS), TiO2 nanotubes (TNTs), and an extra redox mediator. The electron transfer between oxidatively quenched ARS-TNTs and the redox mediator is the key to secure cooperative photocatalysis. The selective aerobic oxidation of primary and secondary amines was constructed by cooperative photocatalysis of ARS-TNTs with 2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (TEMPO+BF4−) driven by green light. Specifically, the activity of anatase TNTs could reach about 2.2 times that of the P25 (Aeroxide P25) TiO2 precursor. Due to increased polarity, TEMPO+BF4− serves more efficiently for electron transfer than (2,2,6,6-tetramethylpiperidin-1-yl)oxy (TEMPO), conferring above 1.5 times of activity that of TEMPO for the selective aerobic conversion of amines. This work features the potential of designing redox mediators in amplifying cooperative photocatalysis driven by visible light.

The nitrogen self-doped porous carbons (NPCs) were prepared using alfalfa as raw material by pyrolysis method without additional nitrogen sources at various pyrolysis temperatures. The NPC supported CuFeO2 (CuFeO2/NPC) composites with large BET surface area (113.18 - 517.56 m2 g−1) were successfully prepared by hydrothermal method without reductant. The NPC prepared at 600 °C (NPC-600) supported CuFeO2 (CuFeO2/NPC-600) possessed the highest catalytic performance for activating peroxydisulfate (PDS) to degrade nimesulide compared to other CuFeO2/NPC composites. The OH, SO4 - and 1O2 were the main reactive species for nimesulide degradation. The oxygen-containing functional groups, pyridinic N, graphitic N, and Fe3+/Fe2+ and Cu2+/Cu+ redox cycles were demonstrated to be extremely important in activating PDS to produce reactive species. The degradation pathway of nimesulide was proposed combined with the HPLC/MS spectra and DFT calculation, and the overall toxicity of nimesulide were effectively alleviated in CuFeO2/NPC-600+PDS system according to toxicity prediction.

The BiOBr modified TiO2 nanotube arrays (BiOBr/TNAs) photoelectrodes were prepared for photoelectrocatalytic (PEC) degradation of p-chloronitrobenzene (p-CNB) under visible light irradiation. The surface structure analysis demonstrated that BiOBr nanoflakes were successfully deposited on the TNAs surface to form tight heterojunction. The BiOBr/TNAs photoelectrodes showed higher PEC degradation efficiency for p-CNB (71.96%) than that by bare TNAs (41.52%) owing to the improved visible-light absorption and reduced charges recombination. The hydroxyl radical and photogenerated holes were the main active species responsible for degradation, dechlorination and mineralization of p-CNB. The coexistence of dissolved anions and humic acid could decline p-CNB removal due to the radical scavengers or competition for active sites. The density functional theory (DFT) calculations indicated that the matched energy bands between BiOBr and TiO2 formed an internal electric field at the heterojunction interface, which promoted the charges migration and separation. The degradation mechanism and pathways of p-CNB were proposed based on the radical scavenging experiments, GC-MS spectra and theoretical calculations. The toxicity of identified intermediates from p-CNB was declined after PEC degradation.

The fast recombination of photogenerated charges, low utilization of visible light and difficult recyclability of photocatalysts limit the practical application of photocatalysis technology. Therefore, ternary reduced graphene oxide/BiOBr/TiO2 nanotube arrays (GB/TNAs) photoelectrodes were prepared for the photoelectrocatalytic (PEC) degradation of p-chloronitrobenzene (p-CNB) under visible light irradiation. The internal interaction among different semiconductors demonstrated that the successful fabrication of ternary heterojunction. The photoelectrochemical properties showed that GB/TNAs exhibited higher visible-light absorption property and lower charges recombination than bare TNAs. The p-CNB degradation rate by GB/TNAs reached 0.0055 min−1, which was 3.93 times than that by TNAs (0.0014 min−1). The GB/TNAs effectively solved the recovery of powdered catalysts, and had excellent PEC stability for p-CNB. The coexistence of dissolved anions and humic acid could decline the p-CNB degradation owing to the competition for active sites or behave as the active radical scavengers. The radical quenching experiments and electron spin resonance spectra revealed that the hydroxyl radical and photogenerated holes were the main active species responsible for the degradation, dechlorination and mineralization of p-CNB. The as-prepared GB/TNAs photoelectrodes display a great potential for the degradation of emerging organic contaminants in wastewater.

The “cyborg cells”, living cells with built-in nanoscaffolds, which could integrate the biological function of the cells with the functionality of nanomaterials, have been rarely explored. Here we report a method to construct “cyborg erythrocytes” through the in situ reaction of exogenous calcium and carbonate ions to generate calcium carbonate nanodots inside erythrocytes. The intracellular calcium carbonate nanodots combined with proteins are hidden under the membrane of erythrocytes, which can restrict migration and unexpected accumulation of nanodots in the body, improving the biosecurity of the nanodots. Most importantly, the calcium carbonate nanodots not only do not bring adverse effects on the nature of erythrocytes, but also endow erythrocytes with new properties. The in vitro and in vivo results show that the “cyborg erythrocytes” can remove 80% of lead ions in a blood poisoning model and reduce the lead level in the kidney and liver of mice through a precipitation transformation mechanism. Precipitation of inorganic materials on cell surfaces is well established but intracellular nanoparticle synthesis is less common. Here the crystallisation of calcium carbonate from exogenous ions within red blood cells is shown to selectively sequester Pb(II) from blood and to reduce accumulation of Pb(II) in mouse kidney and liver tissue.

This study investigated the coupled dynamics of the redox transformation of arsenic-containing ferrihydrite, and arsenate desorption and re-adsorption in presence of sulfide. Batch experiments, various microscopic and spectroscopic analyses collectively revealed that electrons from sulfide competitively transferred to ferrihydrite and no arsenate was reduced. The reductive dissolution of ferrihydrite by sulfide led to the quick formation of FeS that competitively decreased the availability of sulfide for its subsequent reduction of ferrihydrite. The quick formation of FeS was followed by a relatively slow transformation of ferrihydrite to magnetite and other Fe(II)-Fe(III) minerals that were primarily bound to the residual ferrihydrite surfaces. As a result of the preservation of As-containing ferrihydrite and surface covering by the secondary minerals, the majority (> 90%)of sorbed arsenate resided in the solid phase, and

Battery electric vehicles (BEVs) and plug-in hybrid electric vehicles (PHEVs) are seen as the most promising alternatives to internal combustion vehicles, as a means to reduce the energy consumption and greenhouse gas (GHG) emissions in the transportation sector. To provide the basis for preferable decisions among these vehicle technologies, an environmental benefit evaluation should be conducted. Lithium iron phosphate (LFP) and lithium nickel manganese cobalt oxide (NMC) are two most often applied batteries to power these vehicles. Given this context, this study aims to compare life cycle energy consumption and GHG emissions of BEVs and PHEVs, both of which are powered by LFP and NMC batteries. Furthermore, sensitivity analyses are conducted, concerning electricity generation mix, lifetime mileage, utility factor, and battery recycling. BEVs are found to be less emission-intensive than PHEVs given the existing and near-future electricity generation mix in China, and the energy consumption and GHG emissions of a BEV are about 3.04% (NMC) to 9.57% (LFP) and 15.95% (NMC) to 26.32% (LFP) lower, respectively, than those of a PHEV.

Three new boronic acid derivatized lanthanide–polyoxometalates (BA-Ln–POMs) were synthesized, in which boronic acids served as bi- or tri-dentate ligands and exhibited interesting coordination ability towards POMs and LnIII. The pH was found to be crucial in controlling the coordination modes of boronic acid and the formation of B–O–Ln and B–O–Nb bridges. Compared with the boronic acid-free Ln–POM, a longer lifetime was observed for compound 2Eu due to the coordination of boronic acids to the EuIII center.

The BiOBr modified TiO2 nanotube arrays (BiOBr/TNAs) heterojunctions were fabricated through anodic oxidation followed by successive ionic layer adsorption and reaction method. The optimum synthetic parameters of BiOBr/TNAs were obtained by the response surface methodology. The surface structure analysis showed that BiOBr nanoflakes were successfully deposited on the surface of TNAs and formed BiOBr/TNAs heterojunctions. The BiOBr/TNAs displayed higher visible light absorption property than bare TNAs due to the intrinsic visible light response of BiOBr and excellent light-scattering property of the formed heterostructure. The photoelectrochemical properties and photoluminescence spectra analysis revealed that an appropriate loading amount of BiOBr on the TNAs could effectively enhance photoconversion efficiency and the separation of photogenerated electron-hole pairs. The photocatalytic degradation efficiency of Rhodamine B (Rh B) by the optimum BiOBr/TNAs reached almost 85% under visible light irradiation, which was much higher than that of bare TNAs (less than 20%). The radical scavenging experiments and electron spin resonance spectra suggested that ·O2– and h+ played crucial roles in the photocatalytic degradation of Rh B. The possible mechanism and degradation pathways of Rh B by BiOBr/TNAs were proposed under visible light irradiation.

As a typical refractory pollutant, p-chloronitrobenzene (p-CNB) from industrial wastewater poses a serious threat to the aquatic environment safety and human health. The photoelectrocatalytic (PEC) technology is regarded as a promising and cleaner approach for p-CNB removal. Therefore, the graphitic carbon nitride (g-C3N4) modified TiO2 nanotube arrays (g-C3N4/TNAs) were prepared as the photoelectrodes for p-CNB degradation. The PEC degradation efficiency for p-CNB by g-C3N4/TNAs (0.00484 min-1) was much higher than that by bare TNAs (0.00135 min-1) under visible light. The g-C3N4/TNAs photoelectrodes exhibited excellent visible-light response, efficient charges separation and high redox potentials of electron/hole, which was favorable for p-CNB degradation. The radical scavenging experiments indicated that both reductive electrons and oxidized species (holes and ·OH) played crucial roles simultaneously during the dechlorination process, whereas the mineralization of p-CNB mainly depended on the photo-generated holes and ·OH. The degradation pathways of p-CNB were proposed through GC/MS spectra. The acute toxicity, bioaccumulation factor and mutagenicity of identified intermediates were reduced after PEC degradation by g-C3N4/TNAs photoelectrodes. The Z-scheme g-C3N4/TNAs provided an efficient approach for simultaneous dechlorination and mineralization of refractory pollutants.

Modifying living cells using in-situ synthesized nanomaterials to endow them with new functions is highly desirable. Herein we report intra- and extra-cellular dual-modified red blood cells (RBCs) with intracellular CaCO3 nanoparticles (NPs) and extracellular polypyrrole-folic acid (PPy-FA) coating, which are exploited as a bifunctional drug carrier. The functionalized living cells (CaCO3@RBC@PPy-FA) are fabricated through first the intracellular in situ reaction of exogenous Ca2+ and CO32- ions to generate CaCO3 NPs, then polymerization of pyrrole and finally modification of folic acid (FA) on the membrane of individual cells, forming a CaCO3@RBC@PPy-FA structure. As a result, such dual-modified RBCs not only preserve the original performances of the cells but also possess the desirable properties as a drug carrier, such as high loading capacity due to the action of CaCO3 NPs, targeting and light-controlled drug release due to the action of PPy-FA. Under NIR laser stimulation, these bifunctional RBCs (DOX-CaCO3@RBC@PPy-FA) present an instant release profile of doxorubicin (DOX) and have high targeting-ability toward cancer cells, achieving a marked synergistic combined photothermal-chemotherapy effect.

Photothermal therapy (PTT) can take advantage of the photothermal effects of photothermal agents to acquire the energy from laser irradiation and convert it into heat. This can intensively elevate the temperature of the surrounding environment to directly destroy the cancer cells. It is expected that PAs with strong absorption in near infrared (NIR) range might possess the ideal tissue-transparent feature and minimal damage to surrounding healthy tissues, beneficial to the practical application. Herein, well-dispersed L-cysteine modified MoS2 (MoS2-Cys) nanospheres with the average diameter of about 422 nm and strong NIR adsorption were successfully synthesized through a facile method. The as-prepared MoS2-Cys nanospheres are composed of nanosheets with the average thickness of about 13.7 nm. The photothermal conversion efficiency of the as-prepared MoS2-Cys nanospheres with the very low concentration of 50 μg/mL was determined to be 35% when exposed to 808 NIR laser at the power density of 0.8 W/cm2, much higher than those of the previous reports with same dose and power density. MoS2-Cys nanospheres possessed the good photothermal ablation effect to significantly inhibit the growth of tumor in vivo. Furthermore, MoS2-Cys nanospheres did not exhibit detectable side effects, suggesting their good in vitro and in vivo biocompatibility.

According to the basic principles of biomineralization, a homogeneous precipitation process involving BSA as the matrix was used to precipitate mixed Ca–Ba, Ca–Cd and Ca–Mn carbonate particles with distinct morphologies and structures at room temperature. The structures and morphologies of these carbonates were investigated using SEM and XRD. It was found that there were distinct differences when two different kinds of divalent metal ions were simultaneously precipitated in the reacting solutions. Moreover, according to the results of FT-IR and TG-DTA, we could conclude that bovine serum albumin also affected the diverse morphologies of Ca–M carbonates besides the influence of divalent metal ions. A self-assembly process coupled with an Ostwald ripening mechanism was also discussed based on a series of time-dependent SEM observations.

The development of multi-shelled hollow carbonate nanospheres (MHCN) for biomedical applications is challenging, and has not been reported. In this study, a facile approach is firstly reported to synthesize hierarchically porous MHCN with controllable shell numbers using a novel strategy called layer-by-layer thermal decomposition of organic acid salts and templates. The choice of organic acid salts as the reactants is innovative and crucial. The shell numbers of porous MHCN can be easily controlled and tuned through adjusting the adsorption temperature of organic acid salts and/or the adsorption ability of the template. The synthetic method can not only open a window to prepare the multi-shelled carbonates but also provide a new strategy to synthesise other multi-shelled inorganic salts. Notably, the hierarchically porous multi-shelled hollow structures empower the carbonates with not only a large specific surface area but also good porosity and permeability, showing great potential for future applications. Herein, our in vitro/vivo evaluations show that CaCO3 MHCN possess a high drug loading capacity and a sustained-release drug profile. It is highly expected that this novel synthetic strategy for MHCN and novel MHCN platform have the potential for biomedical applications in the near future.

The effectiveness of using ligand-assisted strategies to improve the performance of palladium-doped nanoscale zero-valent iron particles (Pd-nZVI) towards contaminant removal has been investigated previously, however, little attention has been given to either the thermodynamics and kinetics of the Pd-nZVI depassivation process or the effect of the presence of co-existent cations. Results of laboratory investigations using EDTA as the ligand of choice indicate that the presence of Ca(II) and Mg(II) ions can significantly improve the ligand-promoted dechlorination efficiency of polychlorinated biphenyls (PCB) with the effect of divalent cations on PCB removal being more significant at higher concentrations of EDTA. The improvement in particle reactivity in the presence of Ca(II) and Mg(II) could be attributed to moderate elimination of outer Fe oxide layers induced by the relatively slow release of free EDTA from Ca and Mg–EDTA complexes. The slow release of free EDTA prevented excessive initial loss of Fe oxide surface sites required for PCB sequestration and ensured that sufficient EDTA remained available for the later-time removal of Fe oxide layers that were continuously formed as Fe0 was oxidized. A mechanistically-based kinetic model for the ligand-promoted dissolution of Pd-nZVI has been developed with this model enabling quantitative understanding of the relatively complex interplay among Ca(II) and Mg(II) ions, EDTA and passivating Fe oxide layers during the contaminant degradation process.

Silver (Ag) has been regarded as a significant antioxidant widely used in biosystem. Nevertheless, the loading level of Ag nanospecies needs to be controlled to prevent their potential risk to human health. Herein, nanocomposite consisting of Ag and molybdenum disulfide (MoS2) has been readily synthesized via a template solvothermal method. Characterized by SEM, TEM and EDX, the Ag@MoS2 composite morphology including nanoflower, hollow sphere and solid sphere could be well controlled by adjusting solvent type and precursor-template ratio during the synthesis process. The composite structure of all three morphologies was further confirmed by XRD, Raman and N2 adsorption-desorption measurements. Ag@MoS2 nanoflower and hollow sphere, in which nanosized Ag was anchored (or encapsulated) within MoS2 nanosheets, obviously boosted the radical (1,1-diphenyl-2-picyrl, DPPH and nitride oxide, NO) scavenging efficiency (minimum IC50,DPPH = 26 μg/mL while IC50,NO = 46 μg/mL) with an Ag dosage much lowered to merely 7∼20 μg/mL. As a contrast, weaker activity of radical scavenging could be observed for Ag@MoS2 solid sphere. Our work will shed new lights on the cost-effective strategy to obtain a biosafe antioxidant.

The AgI/Bi2MoO6/AgBi(MoO4)2 (ABM) multi-heterostructure nanosheet composite system for visible-light photocatalysis have been successfully constructed by a simple one-step calcination method. The ABM multi-heterostructure composite photocatalysts exhibited the obviously improved photocatalytic performance than the pristine Bi2MoO6, AgBi(MoO4)2, and AgI for the degradation of both Tetracycline hydrochloride (TC) and Rhodamine B (RhB). The apparent degradation rate for the ABM sample with the highest photocatalytic activity is 5.4 (TC) and 23.4 times (RhB) that of Bi2MoO6, 4.0 (TC) and 4.9 times (RhB) that of AgBi(MoO4)2, and 1.9 (TC) and 2.4 times (RhB) that of AgI, respectively. This ABM sample with the highest activity showed a Bi2MoO6/AgBi(MoO4)2 composite nanosheet morphology (lateral size: 1–5 u m, thickness: 90−130 nm) with a large amounts of small AgI nanocrystals (diameter: 2−25 nm) uniformly distributed on the surface of composite sheet. The outstanding performance of the ABM composite photocatalysts should be ascribed to the effective separation of photoinduced electron-hole pairs via the multi-heterostructure in ABM, the enhanced visible-light absorption, as well as the two-dimensional (2D) morphology benefitting to the exposure of plenty of surface reactive sites and significant reduction of migration distances of photogenerated carriers. It is hoped that this facile method for the fabrication of multi-heterostructure in our work could promote and inspire the other multicomponent functional nanomaterials used in the fields of not only photocatalysis, but also solar cells, sensors, catalysis, and so on, in the future.

A specific Cu2+ sensor, 2-amino-3-(BODIPYmethyleneamino)maleonitrile (BDM), was established by a simple dehydration between BODIPY and diaminomaleonitrile. Cu2+ could be recognized by BDM over other competing metal ions in acetonitrile with distinct fluorescence emission signal response. Upon the addition of Cu2+ to BDM in acetonitrile, the maximum absorption at approximately 530 nm on the longer wavelength side was quenched, and the emission at 530 nm was ignited simultaneously. The fluorescence intensity enhancement could reach a maximum of 204 times the intensity of the BDM blank solution. The fluorescence “off-on” effect is established according to the Cu2+-induced fast intramolecular oxidative cyclization reaction, which could be deduced from the formation of an imidazole ring appended to the cyclization product (2-BODIPY-1H-imidazole-4,5-dicarbonitrile, BMC). Single-crystal structure analysis of the sensor BDM and cyclization product BMC further demonstrated this oxidative cyclization. Finally, the Cu2+ recognition property of BDM was validated in SiHa cells and living zebrafish. Additionally, the blood-brain barrier of the zebrafish can be penetrated by the BDM dye and the neuron cells in the brain were stained.

Herein, our aim is to develop a drug-free method without obvious side effects to treat cancer through biomineralization of biocompatible inorganic nanomaterials targeting onto cells' membrane to block transport proteins. We selected chondroitin sulfate as optimal target agent and linker to induce the in situ biomineralization of exogenous Ca2+ and CO32- at safe concentration to generate biocompatible calcium carbonate (CaCO3) nanostructures targeting onto cancer cells' membrane. The in vitro and in vivo assays indicated that the generated CaCO3 nanostructures could significantly inhibit the proliferation of cancer cells. Mechanism studies demonstrated that the mineralized CaCO3 nanostructures could bind with 66 membrane proteins. Deeply research revealed that the CaCO3 nanostructures could mainly block transport proteins, e.g. sodium/potassium-transporting ATPase, leading to the collapse of the mitochondrial membrane potential and the increase of the lactate dehydrogenase release into medium, and finally modulated cell cycle and induced the apoptosis of cancer cells. Our results may introduce promising possibilities for efficient and specific cancer treatment by producing biocompatible nanomaterials to block transport proteins.

DNA levels in mitochondria are closely related to serious genetic diseases, but their inherently low levels and high dynamic changes, present great obstacles to the precise detection of trace changes of DNA content in mitochondria, especially for living cells. This work aims to precisely detect DNA in mitochondria of living cells, by using ultrasmall fluorescent hybrid Ag2Se-imide nanodots (NDs) (

Large-scale isolation of nanocrystals of rare-earth-polyoxometalates (RE-POMs) catalysts is important in fundamental research and applications. Here, we synthesized a family of monomeric RE-POMs by the self-assembly of Ta/W mixed-addendum POM {P2W15Ta3O62} and rare-earth (RE) ions. These RE-POMs with molecular formulas of [RE(H2O)7]3P2W15Ta3O62·nH2O (RE = Y, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) are all electroneutral molecular clusters, insoluble in water and common organic solvents. The electronic structures, electrochemical properties, and catalytic activities of them have been investigated by experimental and computational methods. In particular, based on a mild and controllable synthetic process, a convenient and controllable approach to prepare nanocrystals and self-organized aggregates of these monomers has been developed. They exhibit remarkable heterogeneous catalytic activity for cyanosilylation. Both the increased Lewis acid strength of RE in the title compounds, as indicated by theoretical c...

Background Matrine is a naturally occurring alkaloid extracted from the Chinese herb Sophora flavescens. It has been demonstrated to exhibit antiproliferative properties, promote apoptosis, and inhibit cell invasion in a number of cancer cell lines by modulating the NF-κB pathway to downregulate the expression of MMP2 and MM9. It has also been shown to improve the efficacy of chemotherapy when it is combined with other chemotherapy drugs. However, the therapeutic potential of matrine for prostate cancer needs to be further studied. Methods We analyzed KEGG pathways of differential gene expression between matrine-treated and untreated prostate cancer cell lines and identified GADD45B as one of major target genes of matrine based on its role in apoptosis and prognosis value for prostate cancer patients in TCGA database. We further analyzed the expression of GADD45B protein in a tissue microarray and mRNA in TCGA database, and tested the synergistic impacts of matrine and GADD45B overexpression on proliferation, apoptosis, migration and invasion of prostate cancer cell DU145. Results Matrine promoted the expression of GADD45B, a tumor suppressive gene that is involved in the regulation of cell cycle, DNA damage repair, cell survival, aging, apoptosis and other cellular processes through p38/JNK, ROS-GADD45B-p38, or other signal pathways. Although GADD45B is elevated in prostate cancer tissues, levels of GADD45B in prostate tumor tissues are reduced at late stage of tumor invasion, and higher levels of GADD45B predict better survivals of prostate cancer patients. Conclusions Matrine may be used to treat prostate cancer patients to increase the levels of GADD45B to inhibit tumor invasion and improve patient survivals.

Hierarchically structured m-BiVO4 crystals with twin-ball-like, cauliflower-like, pinwheel-like, columnar and spherical morphologies were synthesized by a facile one-pot method in the presence of soluble starch. The physicochemical properties of the material were characterized by means of XRD, SEM, HRTEM/SAED, UV-vis absorption and N2 adsorption techniques. The oriented aggregation mechanism may rationally explain the formation of the hierarchical structure. The assistance of the starch and the pH value of the precursor solution play pivotal roles in the formation of the hierarchical structures with different morphologies because the existing forms of bismuth and starch vary with the pH value of the precursor solution. The photocatalytic activities of the as-prepared BiVO4 samples were evaluated for the photodegradation of Rhodamine B (RhB) in aqueous solution under simulated sunlight irradiation. The highest photocatalytic activity of BiVO4 obtained at pH = 4 may result from several factors, such as the moderate BET surface area, the highest crystallinity, the lowest bandgap and the most exposed (040) face.

A novel portable biosensor for sensitive and selective detection of platelet-derived growth factor-BB (PDGF-BB) had been developed based on the specific recognition between aptamer and protein using a personal glucose meter (PGM) as readout. In the presence of PDGF-BB, the primary aptamer of PDGF-BB which is bound to the surface of streptavidin magnespheres paramagnetic particles (SA-PMPs) reacts quantitatively with invertase-functionalized secondary aptamer of PDGF-BB to form a stable complex, resulting in the attachment of invertase on the SA-PMPs. Subsequently, the invertase catalyzes the hydrolysis of sucrose to produce a large amount of glucose and quantitative readout by the PGM. The enhanced signal of the PGM has a relationship with the concentration of PDGF-BB in the range of 1.0 × 10(-14) M~3.16 × 10(-12) M, and the detection limit is 2.9 fM. The proposed portable biosensor had been successfully applied to assay the PDGF-BB in saliva samples.

On the basis of the different diffusivity and existence of electrostatic repulsion between long and short DNA on the negatively changed indium tin oxide (ITO) microelectrode, a simple but sensitive immobilization free solution-phase electrochemical method for DNA methylation detection and inhibitor screening has been developed. Electroactive substance (methylene blue) tagged at the penultimate base T close to the 3'-terminal first, in the absence of DNA methylation, methylene blue-labeled electroactive fragments cannot be generated by Dpn I and results in a weak electrochemical response being detected on the ITO electrode. On the contrary, a remarkable electrochemical response can be achieved by the cleavage in the presence of DNA methylation since methylene blue-labeled electroactive fragments can be generated and aggregate on the ITO electrode. The proposed system does not need complex operation procedures such as bisulfite treatment, PCR amplification, and electrode immobilization. Six ITO microelectrodes had been assembled on the same microchip, which can achieve the parallel detection of the same sample and improve the experimental efficiency of drug screening. The system was used to conveniently and specifically monitor the change of the DNA methylation level with high sensitivity and selectivity. The proposed system has the potential application to screen the drugs as inhibitors on the activity of methyltransferase in the clinic.

Using three different amino acids (AAs) as organic matrices, including the highly nonpolar hydrophobic l-valine, the positively charged l-arginine and the less polar uncharged l-serine, calcium carbonate (CaCO3) with different morphologies and polymorphs were synthesized by a facile gas diffusion reaction based on biomimetic strategy. Compared with the control cubic calcite obtained in the absence of AAs, the product from l-valine was cubic calcite aggregates assembled by nano-platelets. The product from l-arginine was spherical vaterite aggregates assembled by spherical nanoparticles. The product from l-serine was the mixture of cubic calcite and spherical vaterite. The structures and properties of the side chains of the AAs exerted the significant effects on the nucleation and growth of the CaCO3. The formation mechanisms of the CaCO3 in the presence of AAs are preliminarily discussed. The results suggest that the polymorphs and morphologies of the inorganic nanomaterials might be easily adjusted through the careful selection of the organic matrices.

Hierarchical NiO hollow microspheres with five different sizes have been synthesized by a simple refluxing method. The sizes of the hierarchical NiO hollow microspheres can be facilely tuned by altering the sizes of functionalized polystyrene particles (PS) templates. Firstly, Ni(OH) 2 nanoflakelets assembled onto the surface of the functionalized PS to form core/shell structures. Secondly, Ni(OH) 2 hollow shells were obtained after removal of the core by dissolving PS latex in toluene. Finally, through the calcinations of the Ni(OH) 2 hollow shells, hierarchical NiO hollow microspheres with the diameters of 237, 308, 712, 892 and 1157 nm were obtained, respectively. Adsorption of Congo red (CR) onto the as-prepared five samples from aqueous solution was investigated. The results showed that the as-prepared NiO hollow microspheres were effective adsorbents for the removal of CR pollutant from waste water as a result of their unique hierarchical structures and high specific surface areas. Moreover, the adsorption capacities for CR are different due to the different sizes of NiO hollow microspheres. It was observed that the adsorption capacity increased with the decrease of the size of hollow microspheres. Especially, the smallest hierarchical NiO hollow microspheres have the highest adsorption capacity, which could achieve 526.3 mg/g at room temperature (pH 7.0). Most importantly, the adsorbent can be easily renewed, which will be a great potential material in real applications.

Electrophilic aromatic nitration using N2O5 as a green nitrating agent catalyzed by MoO3–SiO2 under mild conditions has been described. A series of MoO3–SiO2 catalysts with varying MoO3 loadings (5–20 mol%) were prepared by sol–gel technique and characterized using FTIR, XRD, SEM, BET and NH3–TPD to study its surface properties. MoO3–SiO2 shows good catalytic activity and reusability for the nitration of alkyl and halogen aromatics giving high conversions, but less efficiency for the deactivated aromatics. Reactions conducted under non-acidic conditions using N2O5 makes the process safe and environmentally friendly.

Currently, environmental pollution caused by organic compounds leads to severe negative consequences in the human society. Therefore, the removal of these pollutants from aqueous media has become one of the most important issues in environmental science. In the present study, CdS QDs were successfully prepared under aqueous conditions using l -arginine as the stabilizing agent. Optical property determination results reveal that the CdS QDs exhibited strong absorption and photoluminescence in a visible wavelength region. Moreover, the CdS QDs could effectively degrade two organic dyes under visible light irradiation. This suggested that the CdS QDs prepared in this work might be used as the potential photocatalyst to effectively treat the organic pollutants under visible light irradiation.

The present study attempted to examine the effects of bile acid pool size on liver regeneration after hepatectomy. The rats were fed on 0.2% cholic acid (CA) or 2% cholestyramine for 7 days to induce a change in the bile acid size, and then a partial hepatectomy (PH) was performed. Rats fed on the normal diet served as the controls. Measurements were made on the rate of liver regeneration, the labeling indices of PCNA, the plasma total bile acids (TBA), and the mRNA expression of cholesterol 7alpha-hydroxylase (CYP7A1), farnesoid X receptor (FXR), and transcription factor c-Jun or c-fos. As compared with the normal and CA groups, the rate of liver regeneration was decreased on the day 3, and 7 after PH; the peak of the labeling indices of PCNA was delayed and the labeling indices were significantly reduced on the day 1; the TBA were also decreased on the day 1; the expression of FXR decreased but that of CYP7A1 increased at any given time; at the 1st, and 3rd h, the expression of c-Jun was declined in the cholestyramine group. The reduction in the bile acid pool size was found to delay the liver regeneration, which may be caused by the down-regulation of FXR and c-Jun expression.

A fluorescent agent (DMT) was screened for recognizing triplex DNA with a specific and selective characteristic, which was embedded into the triplex DNA structure. The triplex DNA was firstly formed by a complementary target sequence through two distinct and sequential events. The conditions including pH and hybridization time, fluorescent agent concentration and embedding time were optimized in the experiment. Under the optimum conditions, the fluorescence signal was enhanced up to 9-fold in comparison with the DMT embedding into the ssDNA, dsDNA and G-quadruplexes. Under the same fluorescence conditions, the changes of the fluorescence signal were also investigated by several kinds of base mismatched DNAs in the experiment. The results showed that our biosensor provided excellent discrimination efficiency toward the perfectly mismatched target DNA with no formation of triplex DNA. We preliminarily deduced the mechanism of the fluorescent reagent for recognizing triplex DNA with high specificity and selectivity.

In this study sodium dithionite (NaS2O4) and sodium borohydride (NaBH4) were employed as reducing agents for the synthesis of nanosized iron-based particles. The particles formed using NaBH4 (denoted nFe(BH4)) principally contained (as expected) Fe(0) according to XAS and XRD analyses while the particles synthesized using NaS2O4, (denoted nFe(S2O4)) were dominated by the mixed Fe(II)/Fe(III) mineral magnetite (Fe3O4) though with possible presence of Fe(0). The ability of both particles to reduce trichloroethylene (TCE) under analogous conditions demonstrated remarkable differences with nFe(BH4) resulting in complete reduction of 1.5mM of TCE in 2h while nFe(S2O4) were unable to effect complete reduction of TCE in 120 h. Moreover, acetylene was the major reaction product formed in the presence of nFe(S2O4) while the major reaction product formed following reaction with nFe(BH4) was ethylene, which was further reduced to ethane as the reaction proceeded. Considering that effective Pd reduction to Pd(0) requires the presence of Fe(0), this is consistent with our finding that Fe(0) is not the dominant phase formed when employing dithionite as a reducing agent under the conditions employed in this study.

Using homemade multiwalled carbon nanotubes (CNT) as the promoter, sulfurized Co-Mo-K catalysts (denoted CoiMojKk-x%CNT) were prepared by the coprecipitation method. Their catalytic performance for the synthesis of higher alcohols from syngas was evaluated and compared with that of the CNT-free counterpart (CoiMojKk). Appropriate incorporation of a minor amount of CNT into CoiMojKk led to a significant increase in CO conversion and the selectivity for the higher alcohols. Under the reaction conditions of 5.0 MPa, 623 K, V(H2):V(CO):V(N2) = 60:30:10, and GHSV = 3600 ml/(g·h), the observed space-time-yield of total (C1–4) alcohols reached 241.5 mg/(g·h) with 21.6% of CO conversion over the Co1Mo1K0.3-10%CNT catalyst, which was 1.84 times that over the Co1Mo1K0.3 catalyst. Ethanol became the dominant product of the CO hydrogenation under the conditions mentioned above. The water-gas-shift (WGS) side reaction was inhibited to a great extent over the CNT-promoted catalyst. The results of catalyst characterization indicated that the addition of a small amount of CNT into the Co1Mo1K0.3 catalyst did not cause an obvious change in the apparent activation energy for the conversion of CO but led to an increase in the molar percentage of the catalytically active Mo species (Mo4+) in the total amount of Mo at the surface of the working catalyst. On the basis of the temperature-programmed desorption results, it could be inferred that under the conditions of the higher alcohol synthesis, there existed a considerably larger amount of reversibly adsorbed H species on the CNT-promoted catalyst, which would generate a surface microenvironment with high steady-state concentration of the adsorbed H species on the catalyst and thus increase the rate of a series of surface hydrogenation reactions. In addition, high steady-state concentration of adsorbed H species on the surface of the catalyst would effectively inhibit the WGS side reaction. These factors considerably contribute to the increase in the yield of the main product.