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Imaging platforms that enable long-term, high-resolution imaging of biofilms are required to study cellular level dynamics within bacterial biofilms. By combining high spatial and temporal resolution and low phototoxicity, lattice light sheet microscopy (LLSM) has made critical contributions to the study of cellular dynamics. However, the power of LLSM has not yet been leveraged for biofilm research because the open-on-top imaging geometry using water-immersion objective lenses is not compatible with living bacterial specimens; bacterial growth on the microscope's objective lenses makes long-term time-lapse imaging impossible and raises considerable safety concerns for microscope users. To make LLSM compatible with pathogenic bacterial specimens, we developed hermetically sealed, but optically accessible, microfluidic flow channels that can sustain bacterial biofilm growth for multiple days under precisely controllable physical and chemical conditions. To generate a liquid- and gas-tight seal, we glued a thin polymer film across a 3D-printed channel, where the top wall had been omitted. We achieved negligible optical aberrations by using polymer films that precisely match the refractive index of water. Bacteria do not adhere to the polymer film itself, so that the polymer window provides unobstructed optical access to the channel interior. Inside the flow channels, biofilms can be grown on arbitrary, even nontransparent, surfaces. By integrating this flow channel with LLSM, we were able to record the growth of S. oneidensis MR-1 biofilms over several days at cellular resolution without any observable phototoxicity or photodamage.

Developing a practical strategy to fabricate an anti-abrasion and durable superhydrophobic wood surface with ultraviolet (UV) resistance has great practical significance for expanding the application of natural wood. In this study, a robust superhydrophobic layer with a hierarchical micro/nano-roughness structure was modified on the wood surface through in-situ mineralization and polymerization using a simple sol–gel method along with efficient electron beam (EB) curing technology. Hydrophobic agent (polydimethylsiloxane, PDMS), and crosslinking monomer (γ-methacryloxypropyl trimethoxysilane, MAPS) form new covalent bonds between TiO2 particle layer and wood substrate after EB radiation, which endows robust superhydrophobicity and remarkable UV resistance on the wood surface. The as-prepared wood exhibited a water contact angle of approximately 165.7° and obvious repellency to many aqua-phase liquids (cola, strongly acidic, alkaline droplets etc.). Furthermore, the hierarchical micro/nano-protrusion structures remained unchanged and micro/nano particles aggregated tightly on the as-prepared wood surface under harsh external environments (sandpaper abrasion and, ultrasonic treatment), confirming the desirable anti-abrasion and mechanically durable performance of the superhydrophobic surface. After the 18-day UV accelerated weathering test, the TiO2 particle layer conspicuously retained the discoloration and maintained its exceptional repellency toward water. The biomimetic superhydrophobic wood with excellent mechanical durability and UV resistance reveals its potential application in the furniture and architecture fields.

The metal-organic framework (MOF) NTUniv-54 (NTUniv = Nantong University) was assembled via utilizing click chemistry with densely decorated trizole units and exposed metal sites, which exhibited the best methane working ability (197 cm3·cm-3 from 100 to 5 bar and 177 cm3·cm-3 from 65 to 5 bar at 298 K), and the lowest CO2Qst of 22.8 kJ·mol-1 in all triazole-MOFs at room temperature.

Soil salinity is a major environmental stressor that restricts the growth and yield of crops. Plants have evolved more complicated and precise mechanisms to cope with salt stress, as they cannot escape from harmful environments. In the current study we identified and characterized an AP2/ERF transcription factor in rice, OsERF19. The expression of OsERF19 was slightly repressed by salt stress or abscisic acid (ABA) treatment. OsERF19-overexpression (OsERF19-OX) plants displayed enhanced tolerance to salt stress and ABA hypersensitivity compared to wild type and control plants. Furthermore, OsLEA3, OsNHX1, OsHKT6, and OsOTS1 were upregulated in OsERF19-OX plants when the plants were subjected to salt stress. OsRAB21, OsNCED5, and OsP5CS1 were also upregulated in OsERF19-OX plants treated with ABA. Yeast one-hybrid and dual luciferase reporter assays demonstrated that OsERF19 directly targets the promoters of OsOTS1 and OsNCED5 and further increases their transcription. These results suggest that the transcription factor OsERF19 plays a positive role in salt stress and ABA responses in rice.

Summary The capture of radioiodine species during nuclear fuel reprocessing and nuclear accidents is crucial for nuclear safety, environmental protection, and public health. Previously reported emerging materials for iodine uptake cannot outperform commercial zeolites and active carbon under the practical dynamic scenario. Herein, we present a new design philosophy aiming at significantly enhanced specific host-guest interactions and obtain a nitrogen-rich covalent organic framework material by introducing a bipyridine group into the building block for the simultaneous capture of both iodine gas through enhanced electron-pair effect and organic iodide via the methylation reaction. These efforts give rise to not only an ultrahigh uptake capacity of 6.0 g g−1 for iodine gas and a record-high value of 1.45 g g−1 for methyl iodide under static sorption conditions but also, more importantly, a record-high iodine loading capability under dynamic conditions demonstrated from the breakthrough experiments.

The pleated filter cartridges are widely used in industrial production to control particulate emissions and recover valuable particulate matter, where pulse jet cleaning is a major method for filter regeneration. However, for strong hygroscopic and adhesive dust such as Polyacrylamides (PAM), during pulse-jet cleaning the compressed air forms a low temperature zone at the nozzle and will release water to the environment, causing the particles to adhere on the filter after absorbing moisture, resulting in ineffective filter regeneration. Therefore, a higher cleaning pressure or other methods are required to clean the filter surface. In this article, we have proposed a method to collect adhesive dust using dry gas injection and verified its feasibility through pilot experiments. The compressed air injection source was replaced with nitrogen, the curve of system pressure drop shows that nitrogen has good performance in the peeling of adhesive dust from the surface of the pleated filter cartridge. This highlights the effect of the moisture content in the cleaning compressed air on the regeneration of filters clogged with adhesive hygroscopic particles. Therefore, the feasibility of the nitrogen injection was validated, which provides a basis for the future systematic research of industry to collect adhesive dust.

Conventional aromatic compounds tend to exhibit the formation of sandwich-shaped excimers and exciplexes between their excited and ground states at high concentrations or in their aggregated states, causing their fluorescence to weaken or disappear due to the aggregation-caused quenching (ACQ) effect. This limits their applications in concentrated solutions or solid materials. Herein, for the first time, ACQ-based pyrene (Py) units are covalently connected to the surface of polyethylene/polypropylene nonwoven fabric (PE/PP NWF) via electron beam preradiation-induced graft polymerization followed by chemical modification. The matrix can be considered a solid solvent and Py units as a solid solute, such that the amount of Py units can be controlled by varying the reaction time. The obtained fluorescent fabric not only exhibits remarkable fluorescence properties with high fluorescence intensity, high quantum yield (>90%), and excellent fluorescence stability after laundering or in harsh chemical environments, but the fluorescence color and intensity, quantum yield, and lifetime can also be regulated by employing the ACQ effect. Additionally, the as-prepared fluorescent fabric can effectively distinguish common monocyclic aromatic hydrocarbons via a simple fluorescence response test.

A mixed water-organic solvent used for amidoximation increased the production cost of an amidoxime-based polymer sorbent and was not environmentally friendly as well. In this work, the amidoximation of an ultrahigh molecular weight polyethylene fiber co-grafted with acrylonitrile and methacrylic acid was carried out in aqueous solution without the use of an organic solvent. The effects of amidoximation parameters including NH2OH concentration, temperature, time, and various solvents on the uranium adsorption performances in both uranium-spiked brine and simulated seawater were investigated. Results indicated that the optimal amidoximation parameters were 5% (w/v) NH2OH, 80 °C, and 24 h. The uranium adsorption capacities of the sorbents amidoximated in aqueous solution were comparable with those of sorbents amidoximated in the various mixed water-organic solvents. Moreover, in comparison with both acidic (pH ∼3) and alkalic (pH ∼11) aqueous solution, the sorbent amidoximated in neutral (pH ∼7) NH2OH aqueous solution achieved higher uranium adsorption capacities in both uranium-spiked brine (112.4 mg/g) and simulated seawater (7.4 mg/g). Additionally, potassium hydroxide (KOH) treatment was a necessary process and indeed significantly increased the uranium adsorption capacity.

Advanced oxidation processes (AOPs) present one of the most promising strategies to deal with the ever-growing water pollution. However, fabricating improved catalysts with large size (meter level or larger), long-term stability, and adequate activity is still a formidable challenge in practical applications. In this study, cobalt ions are covalently linked on the polypropylene nonwoven fabric (P-PFeCo) via irradiation graft polymerization and used as highly efficient and stable reaction sites to degrade highly toxic and difficult biodegradable organics by activating peroxymonosulfate (PMS). The presence of graft chains not only generates a well-defined monometallic reaction microenvironment, but also promotes electron transfer. The as-prepared catalyst combines these exceptional properties for efficient removal of dyes or antibiotics via activating PMS within 8 min and exhibits remarkable durability over a wide pH range and recyclability after five consecutive runs with trace cobalt leaching. The X-ray absorption fine structure (XAFS) spectroscopy and density functional theory (DFT) calculations reveal that the CoN4(H2O)2 site acts as an active site for activating PMS. A device in a flow mode is also constructed to illustrate the potential applications of P-PFeCo. We consider that the catalytic process along with the large-sized substrate will broaden a new horizon in terms of designing high-performance catalysts for PMS activation in wastewater treatment.

Finding efficient actinide decorporation agents is crucial for public health and the development of the nuclear industry. The current inventory of decorporation agents is predominately limited to a handful of ligands. In this work, a two-dimensional (2D) covalent organic nanosheet (CON) material was rationally designed and tested for in vivo uranium decorporation. This material is extensively grafted with amidoxime (AO), a classic uranium-recognition ligand, which not only provides selective binding sites for uranyl but also expands the interlayer spacing of CON, making the active sites more accessible. Significantly, the results of in vivo experiments demonstrate that, in both prophylactic and prompt administration groups, CON-AO exhibits a higher excretion ratio of uranium from kidneys than that of ZnNa

Removal of 99TcO4− from legacy defense nuclear tank waste at Savannah River Site is highly desirable for the purpose of nuclear safety and environmental protection, but currently not achievable given the extreme conditions including high alkalinity, high ionic strength, and strong radiation field. Herein, we present a potential solution to this long-term issue by developing a two-dimensional cationic metal organic framework SCU-103, showing ultrahigh stability in alkaline aqueous media and great resistance to both β and γ radiation. More importantly, it is very effective for 99TcO4− separation from aqueous media as demonstrated by fast exchange kinetics, high sorption capacity, and superior selectivity, leading to the successful removal of 99TcO4− from actual Savannah River Site high level tank waste for the first time, to the best of our knowledge. In addition, the uptake mechanism is comprehensively elucidated by molecular dynamics simulation and density functional theory calculation, showing a unique chemical recognition of anions with low charge density., Separation of 99TcO4− from nuclear waste at the Savannah River Site is hampered by the extreme conditions. Here, the authors propose a solution by developing an alkaline-resistant metal organic framework material featuring unique recognition sites for selective incorporation of 99TcO4− anions.

A new technique is proposed for the in situ printing of fluorescent fabrics with superior fluorescent properties that have the potential for continuous roll-to-roll production in the industry. Nonconjugated chemical moieties were covalently connected to polyethylene/polypropylene nonwoven fabric (PE/PP NWF) to successfully prepare fluorescent PE/PP NWF, which emits a bright blue light and has a high quantum yield (∼83.35%) that can be attributed to a unique aggregation-induced emission effect. The fluorescent PE/PP NWF exhibits excellent fluorescent stability under high shear forces during accelerated laundering and in harsh chemical environments. The fluorescent PE/PP NWF can also be tailored into diverse shapes and printed in situ with high resolution. The versatility of the method was also demonstrated by fabricating fluorescent materials with different polymer matrices such as Nylon 66 fiber and PE terephthalate membrane.

Immobilization of photocatalysts on substrates is an important factor for water purification in practical applications. In this study, an efficient Ag@AgBr photocatalytic coating was attached onto the surface of cotton fabric via radiation-induced graft polymerization and subsequent chemical reactions, and the resultant product was denoted as Cot-Ag@AgBr. The graft chains acted not only as a source of bromine, but also as an intermediate layer to anchor the Ag@AgBr photocatalytic coating via strong electrostatic interactions. The immobilized Ag@AgBr photocatalytic coating exhibited outstanding photocatalytic properties for organic dye degradation under visible light irradiation. Furthermore, Cot-Ag@AgBr presented high stability and robust durability, which conferred its excellent visible-light-driven photocatalytic activity after five rounds of photodegradation. After 10 min of ultrasonication, the amount of Ag@AgBr precipitate that leached from the Cot-Ag@AgBr was

When a pipeline is under fire safety work construction, the stack effect of the pipeline will increase the diffusion rate of nitrogen, reduce the oxygen content, and cause asphyxia. To prove the influence of the stack effect of the pipeline on the nitrogen movement in the pipeline and put forward effective ventilation control measures, the formation mechanism, gas diffusion law, and ventilation parameters of the stack effect of the oil and gas pipelines are studied through theoretical derivation and numerical simulation. The results show that the nitrogen concentration at the height of the breathing zone in the hot zone first increases and then decreases along the axial distance. The larger the temperature difference, the faster the diffusion speed of nitrogen in the fire safety work area, and the lower the oxygen concentration. When the temperature difference increases to 30 °C, the maximum oxygen concentration in the work area is 0.177; to control the problem of low oxygen content caused by the stack effect, three ventilation schemes are put forward. Through the analysis that installing fans symmetrically on both sides, 4 m away from the pipe opening, can effectively reduce the stack effect intensity when the optimal working wind speed of the fan is 4 m/s. The findings of this study can help in better understanding the causes of the chimney effect during pipeline fire safety work and provide theoretical basis for controlling personnel suffocation caused by the chimney effect.

Pincer-type main-group complexes have attractive properties and excellent potential as catalysts. A set of sterically hindered trianionic pincer-type phosphorus complexes have been shown to activat...

Crystalline porous materials such as covalent organic frameworks (COFs) are advanced materials to tackle challenges of catalysis and separation in industrial processes. Their synthetic routes often require elevated temperatures, closed systems with high pressure, and long reaction times, hampering their industrial applications. Here we use a traditionally unperceived strategy to assemble highly crystalline COFs by electron beam irradiation with controlled received dosage, contrasting sharply with the previous observation that radiation damages the crystallinity of solids. Such synthesis by electron beam irradiation can be achieved under ambient conditions within minutes, and the process is amendable for large-scale production. The intense and targeted energy input to the reactants leads to new reaction pathways that favor COF formation in nearly quantitative yield. This strategy is applicable not only to known COFs but also to new series of flexible COFs that are difficult to obtain using traditional methods.

In this work, the electronic excited states of hypoxanthine in solution such as water and acetonitrile are investigated by the time-dependent density functional theory (TDDFT) method. We demonstrated for the first time that the intermolecular excited-state electron transfer (ESET) from solvents to the hypoxanthine through excited-state intermolecular hydrogen-bonds cluster exhibits obvious site-selectivity. Excited-state electron transfer could only occur at the N7 site of hypoxanthine molecule in water solution, while that is the N9 site in acetonitrile. Potential energy surfaces for different electronic states of hypoxanthine with and without the influence of the excited-state hydrogen bonding cluster are also discussed. Site-selective ESET is proposed to induce the internal conversion of hypoxanthine from S2 state to S1 at a conical intersection, which is responsible for the ultrashort lifetime of hypoxanthine in excited state in solution. These results pave a novel way to understand the photophysical and photochemical behaviors of DNA bases and their derivatives in solution phase.

A new UHMWPE-based conductive fabric was successfully prepared by radiation-induced graft polymerization and subsequent post-modification, followed by electroless deposition. The chemical structure and composition of modified UHMWPE fabrics were investigated in detail by ATR-FTIR, 29Si NMR, and XPS to confirm grafting and post-modification. After electroless deposition, the morphology, thermal stability, and crystal structure of original and modified fabrics were characterized by SEM, TG, DSC and XRD. Cu-deposited UHMWPE fabric exhibited much better thermal resistance than that of UHMWPE and Cu@UHMWPE-g-PAAc. In order to improve the oxidation resistance of copper-deposited fabric, nickel was processed on copper-coated UHMWPE fabric to protect the copper layer. An electromagnetic shielding effect test showed the nickel–copper coated UHMWPE fabric could shield 94.5% of the electromagnetic wave in the frequency range of 8–12 GHz. This work provides an approach for addressing the issue of poor thermal resistance of metal-coated polymeric materials due to the inherent low melting point of the organic support.

A new approach in which a low symmetry cluster meets a low symmetry ligand to sharply boost the thermal stability of a MOF via additional inter-linker interactions is presented for the first time, leading to the successful synthesis of a novel binuclear Co-based MOF, {[Co2(L1)2DMF]·1.5DMF·0.75MeOH·1.5H2O}∞ (H2L1 = 5-(pyridin-3-yl) isophthalic acid, NJU-Bai62: NJU-Bai for Nanjing University Bai group), with exceptional thermal stability of up to 450 °C. This work may open up a new avenue for constructing robust MOFs from abundant, unstable, and low symmetry binuclear clusters, which have usually been ignored by most MOF chemists.

By systematic ligand tuning for control of the secondary building units, the use of tridentate carboxylic acid to construct the rod scandium metal-organic framework NTUniv-55 (NTUniv = Nantong University) with high chemical stability and interesting selective gas adsorption was reported.

Background: The triglyceride/glucose index (TyG index) has been suggested as a simple and reliable surrogate insulin resistance (IR) marker for years. However, the association between the TyG index and arterial stiffness in adults is controversial. Therefore, we evaluated this relationship, as measured based on the brachial ankle pulse wave velocity (baPWV), in Japanese adults.Methods: This study selected a total of 912 participants from the NAGALA (NAfld in Gifu Area, Longitudinal Analysis) study conducted from 2004 to 2012.The relationship between TyG index and baPWV was estimated through a logistics model. Subgroup analyses by gender, age, body mass index (BMI), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), estimated glomerular filtration rate (eGFR), and fatty liver were performed. The formula for TyG index was ln [½fasting triglyceride level (mg/dL) × fasting plasma glucose level (mg/dL)].Results: After adjusting for underlying confounders, a linear relationship between TyG and baPWV was discovered. After adjusting for gender, age, body mass index, systolic blood pressure, diastolic blood pressure, high-density lipoprotein cholesterol, fatty liver, and eGFR, TyG, as a continuous variable, was related to an increased risk of baPWV (adjusted odds ratio [adj OR], 1.57; 95% confidence interval [95% CI], 1.14–2.18). Compared with the the TyG index in the first tertile, the probabilities of subjects in the third tertile that developed to baPWV were 1.78-fold higher (adj OR 1.78, 95% CI 1.08–2.95; P for trend 0.024). Stable associations were also observed between the TyG index and baPWV in different variables through subgroup analyses.Conclusions: The TyG index was positively and linearly related to subclinical atherosclerosis in Japanese adults and may be valuable as a predicted marker.

Alkyl-PAHs are the predominant form of PAHs in crude oils which are supposed to demonstrate different toxicities compared to non-alkyl PAHs. Little information is available about the toxicity of alkyl-PAHs on marine Artemia. This study addressed and compared the lethal, behavioral, growth and developmental toxicities of three alkyl-PAHs, namely 3-methyl phenanthrene (3-mPhe), retene (Ret) and 2-methyl anthracene (2-mAnt), to their non-alkyl forms, phenanthrene (Phe) and anthracene (Ant) using Artemia parthenogenetica (nauplii

Plant WRKY transcription factors play crucial roles in plant growth and development, as well as plant responses to biotic and abiotic stresses. In this study, we identified and characterized a WRKY transcription factor in rice, OsWRKY50. OsWRKY50 functions as a transcriptional repressor in the nucleus. The transcription of OsWRKY50 was repressed under salt stress conditions, but activated after abscisic acid (ABA) treatment. OsWRKY50-overexpression (OsWRKY50-OX) plants displayed increased tolerance to salt stress compared to wild type and control plants. The expression of OsLEA3, OsRAB21, OsHKT1, 5, and OsP5CS1 in OsWRKY50-OX were much higher than wild type and control plants under salt stress. Furthermore, OsWRKY50-OX displayed hyposensitivity to ABA-regulated seed germination and seedling establishment. The protoplast-based transient expression system and yeast hybrid assay demonstrated that OsWRKY50 directly binds to the promoter of OsNCED5, and thus further inhibits its transcription. Taken together, our results demonstrate that rice transcription repressor OsWRKY50 mediates ABA-dependent seed germination and seedling growth and enhances salt stress tolerance via an ABA-independent pathway.

Luminescent covalent organic frameworks (COFs) find promising applications in chemical sensing, photocatalysis, and optoelectronic devices, however, the majority of COFs are non or weakly emissive owing to the aggregation-caused quenching (ACQ) or the molecular thermal motion-based energy dissipation. Here, we report a previously unperceived approach to improve luminescence performance of COFs by introducing isotope effect, which is achieved through substitution of hydrogen from high-frequency oscillators X-H (X=O, N, C) by heavier isotope deuterium. Combining the "bottom-up" and in situ deuteration methods generates the first deuterated COF, which exhibits an impressively 19-fold enhancement in quantum yield over that of the non-deuterated counterpart. These results are interpreted by theoretical calculations as the consequence of slower C/N-D and OD⋅⋅⋅O vibrations that impede the nonradiative deactivation process. The proposed strategy is proved applicable to many other types of emissive COFs.

On the basis of the [Fe3(μ3-O)(COO)6] cluster and 3,3′,5,5′-diphenyltetracarboxylic acid (H4BPTC), three novel metal–organic frameworks (MOFs), NJU-Bai25, NJU-Bai26, and NJU-Bai27 (NJU-Bai for Bai’...

A pure-supramolecular-linker (PSL) approach for the formation of metal–organic frameworks (MOFs) was initially given, which was demonstrated by syntheses of two highly connected and isostructural M...

International audience; The chemistry of d-block metal-metal multiple bonds has been extensively investigated in the past 5 decades. However, the synthesis and characterization of species with f-block metal-metal multiple bonds are significantly more challenging and such species remain extremely rare. Here, we report the identification of a uranium-rhodium triple bond in a heterometallic cluster, which was synthesized under routine conditions. The uranium-rhodium triple-bond length of 2.31 angstrom in this cluster is only 3% longer than the sum of the covalent triple-bond radii of uranium and rhodium (2.24 angstrom). Computational studies reveal that the nature of this uranium-rhodium triple bond is 1 covalent bond with 2 rhodium-to-uranium dative bonds. This heterometallic cluster represents a species with f-block metal-metal triple bond structurally authenticated by X-ray diffraction. These studies not only demonstrate the authenticity of the uranium-metal triple bond, but also provide a possibility for the synthesis of other f-block metal-metal multiple bonds. We expect that this work may further our understanding of the bonding between uranium and transition metals, which may help to design new d-f heterometallic catalysts with uranium-metal bonds for small-molecule activation and to promote the utilization of abundant depleted uranium resources.

A bifunctional interfacial layer was introduced onto the surface of cotton fabric which not only enhanced the interfacial bonding between Ag@ZnO and organic substrates but also improved the photocatalytic performance simultaneously. In detail, a modified cotton fabric (denoted as Cot-g-Si/Ag@ZnO) was fabricated through radiation-induced graft polymerization of γ-methacryloxypropyl trimethoxysilane and followed the in-situ formation of ZnO and loading of Ag nanoparticles simultaneously. Owing to ZnOSi between the graft chains and Ag@ZnO photocatalyst, the charge carrier concentration increased and Ag was prevented from oxidizing through the partial separation from ZnO, leading to enhanced near-field amplitudes of the localized surface plasmon resonance. Cot-g-Si/Ag@ZnO also exhibited excellent photocorrosion resistance, photostability and laundering durability. Its photocatalytic activity was fully maintained after several photodegradation cycles; moreover, after laundering durability test, the photocatalytic activity was improved compared with the newly prepared one. Credible mechanism for the photocatalytic activity of Cot-g-Si/Ag@ZnO under sunlight irradiation is proposed.

A new amide-functionalized metal-organic framework (AFMOF) with the combined feature of highly selective CO2 adsorption and high thermal and chemical stability, [Sc3(μ3-O)(L)1.5(H2O)3Cl] n [NJU-Bai49; NJU-Bai for Nanjing University Bai's group, H4L = 5-(3,5-dicarboxybenzamido)isophthalic acid], was synthesized that exhibits 4.5 wt % CO2 uptake at 298 K and 0.15 bar and the highest selectivity for CO2/N2 (166.7) among all AFMOFs. Grand canonical Monte Carlo simulations further indicate that both the decorated amide group and the open metal site act as CO2 binding sites, which may contribute to its highly selective CO2 uptake.

99Tc is one of the most problematic fission products in the nuclear fuel cycle owing to its large inventory in used nuclear fuel, long half-life, potential radiation hazard, high environmental mobility of its major species 99TcO4−, and its redox-active nature. Ideally, 99TcO4− should be removed at the first stage, when the used fuel rods are dissolved in highly concentrated nitric acid solution, which can substantially reduce its interference with the solvent extraction process through catalytic redox reactions with the key actinides and diminish the chance of discharge into the environment as the volatile species during the waste vitrification process. However, this task cannot be achieved by any of the reported anion-scavenging materials including traditional polymeric anion-exchange resins, inorganic cationic framework materials, and recently developed cationic metal–organic framework materials, because they either are not stable under the extreme conditions of the combined high acidity and strong radiation field or do not possess the required uptake selectivity towards 99TcO4− in the presence of a huge excess of competing anions such as NO3− and SO42−. Herein, we present the first study of 99TcO4− removal under extreme conditions by a two-dimensional conjugated cationic covalent organic framework material, SCU-COF-1. This material exhibits ultrahigh acid stability, great resistance towards both large-dose β and γ irradiation and unprecedented 99TcO4− uptake capabilities including extremely fast sorption kinetics (sorption equilibrium can be reached within 1 min), ultrahigh uptake capacity (702.4 mg g−1 for the surrogate ReO4− at a slightly elevated temperature), and good anion-exchange selectivity towards 99TcO4−. These excellent features endow SCU-COF-1 with the practical capabilities of separating 99TcO4− from both simulant highly acidic fuel reprocessing solutions (3 M nitric acid) and low-activity waste streams at the US legacy nuclear site. The anion-exchange mechanism and the 99TcO4− uptake selectivity are further demonstrated and clearly visualized by the molecular dynamics simulation investigations.

A new kind of highly durable, electrically conductive UHMWPE fibers coated with copper was fabricated through a novel, simple, and universal process in this paper. Poly(acrylic acid) was anchored o...

WRKY transcription factors (TFs) have been reported to respond to biotic and abiotic stresses and regulate plant growth and development. However, the molecular mechanisms of WRKY TFs involved in drought stress and regulating plant height in rice remain largely unknown. In this study, we found that transgenic rice lines overexpressing OsWRKY55 (OsWRKY55-OE) exhibited reduced drought resistance. The OsWRKY55-OE lines showed faster water loss and greater accumulation of hydrogen peroxide (H2O2) and superoxide radical (O2−·) compared to wild-type (WT) plants under drought conditions. OsWRKY55 was expressed in various tissues and was induced by drought and abscisic acid (ABA) treatments. Through yeast two-hybrid assays, we found that OsWRKY55 interacted with four mitogen-activated protein kinases (MAPKs) that could be induced by drought, including OsMPK7, OsMPK9, OsMPK20-1, and OsMPK20-4. The activation effects of the four OsMPKs on OsWRKY55 transcriptional activity were demonstrated by a GAL4-dependent chimeric transactivation assay in rice protoplasts. Furthermore, OsWRKY55 was able to reduce plant height under normal conditions by decreasing the cell size. In addition, based on a dual luciferase reporter assay, OsWRKY55 was shown to bind to the promoter of OsAP2-39 through a yeast one-hybrid assay and positively regulate OsAP2-39 expression. These results suggest that OsWRKY55 plays a critical role in responses to drought stress and the regulation of plant height in rice, further providing valuable information for crop improvement.

Palladium isotopes as fission products in used nuclear fuel (UNF) represent precious alternative resources of this noble metal besides its natural reserves and therefore has a high extraction value. However, although solvent extraction of Pd from UNF has been considered for several decades, its practical use is still challenging mostly originating from the harsh fuel reprocessing conditions that lead to the extractant decomposition and the vast co-existing metal ions that depress the extraction efficiency. Herein, we present an interlayer synergistic binding strategy, a metal-recognition manner markedly deviating from chelation within a single ligand molecule in solvent extraction, for selective palladium chelation by a radiation-resistant and acid-stable salicylaldimine-based covalent organic framework (COF-TzDa), where the binding sites are pre-organized and spatially separated for the preference of Pd coordination between adjacent COF layers. COF-TzDa, as expected, shows ultrahigh extraction selectivity towards Pd ions both in static and dynamic conditions, primarily due to that the preorganized Pd-specific binding sites are less prone to match other undesired metal ions. Fast adsorption kinetics, high adsorption capacity (265.4 mg g-1), and more importantly one-round enrichment and purification of Pd from the simulated high level nuclear waste solution are unprecedentedly achieved. The powder X-ray diffraction analysis, X-ray photoelectron spectroscopy results, and in-depth density functional theory corroborate the interlayer synergistic binding to be the result of enol-to-keto tautomerization where oxygen donors from two adjacent layers work together in a cooperative fashion. This work demonstrates the feasibility of structure-engineering of framework materials in designing upgraded adsorbent for targeted guests.

We disclose the intrinsic semiconducting properties of one of the largest mixed-valent uranium clusters, [H3 O+ ][UV (UVI O2 )8 (μ3 -O)6 (PhCOO)2 (Py(CH2 O)2 )4 (DMF)4 ] (Ph=phenyl, Py=pyridyl, DMF=N,N-dimethylformamide) (1). Single-crystal X-ray crystallography demonstrates that UV center is stabilized within a tetraoxo core surrounded by eight uranyl(VI) pentagonal bipyramidal centers. The oxidation states of uranium are substantiated by spectroscopic data and magnetic susceptibility measurement. Electronic spectroscopy and theory corroborate that UV species serve as electron donors and thus facilitate 1 being a n-type semiconductor. With the largest effective atomic number among all reported radiation-detection semiconductor materials, charge transport properties and photoconductivity were investigated under X-ray excitation for 1: a large on-off ratio of 500 and considerable charge mobility lifetime product of 2.3×10-4 cm2 V-1 , as well as a high detection sensitivity of 23.4 μC Gyair-1 cm-2 .

Ti-6Al-4V (TC4) has been widely used in dentistry as an implant biomaterial but is faced with difficulties in forming parts by traditional processing methods. Directed energy deposition (DED), a promising additive manufacturing technology, is very suitable for developing TC4/ZrO2 composite with different proportions of nano-ceramic additions (0, 5 or 10 wt%). As the content of alloying element Zr increased, the grains were refined, and the lattice distortion was more severe due to solid solution, both of which caused Vickers hardness of the composite to increase from 308 to 485. The electrochemical tests and corrosion morphology analysis indicated that the corrosion was intensified with the decrease of pH and the increase of F− ion concentration. The corrosion product detection showed that ZrO2 oxide might reduce the compactness of the TC4 passive film containing TiO2 and Al2O3, which resulted in a slight decrease in corrosion resistance but still satisfied the clinical requirements. Cytotoxicity and cytoskeleton staining results demonstrated that the composite was beneficial to biological safety and biocompatibility.

Considerable attention has been devoted to the in-situ deposition of zinc oxide (ZnO) nanowires (ZnO-NWs) on the surface of organic supports, due to their very wide applications in superhydrophobicity, UV shielding, and nanogenerators. However, the poor interfacial bond strength between ZnO-NWs and its support limits their applications. Herein, we developed a facile process to grow robust ZnO-NWs on a polyethylene terephthalate (PET) fabric surface through simultaneous radiation-induced graft polymerization, hydrothermal processing, and in-situ nano-packaging, the obtained materials were denoted as PDMS@ZnO-NWs@PET. The introduction of an adhesion and stress relief layer greatly improved the attachment of the ZnO-NWs to the support, especially when the material was subjected to extreme environment conditions of external friction forces, strong acidic or alkaline solutions, UV-irradiation and even washing with detergent for a long time. The PDMS@ZnO-NWs@PET material exhibited excellent UV resistance, superhydrophobicity, and durability. The ZnO-NWs retained on the fabric surface even after 30 cycles of accelerated washing. Therefore, this process can be widely applied as a universal approach to overcome the challenges associated with growing inorganic nanowires on polymeric support surfaces.

Background Most cancers favor glycolytic-based glucose metabolism. Hexokinase-2 (HK2), the first glycolytic rate-limiting enzyme, shows limited expression in normal adult tissues but is overexpressed in many tumor tissues, including ovarian cancer. HK2 has been shown to be correlated with the progression and chemoresistance of ovarian cancer and could be a therapeutic target. However, the systemic toxicity of HK2 inhibitors has limited their clinical use. Since follicle-stimulating hormone (FSH) receptor (FSHR) is overexpressed in ovarian cancer but not in nonovarian healthy tissues, we designed FSHR-mediated nanocarriers for HK2 shRNA delivery to increase tumor specificity and decrease toxicity. Results HK2 shRNA was encapsulated in a polyethylene glycol-polyethylenimine copolymer modified with the FSH β 33–53 or retro-inverso FSH β 33–53 peptide. The nanoparticle complex with FSH peptides modification effectively depleted HK2 expression and facilitated a shift towards oxidative glucose metabolism, with evidence of increased oxygen consumption rates, decreased extracellular acidification rates, and decreased extracellular lactate and glucose consumption in A2780 ovarian cancer cells and cisplatin-resistant A2780CP counterpart cells. Consequently, cell proliferation, invasion and migration were significantly inhibited, and tumor growth was suppressed even in cisplatin-resistant ovarian cancer. No obvious systemic toxicity was observed in mice. Moreover, the nanoparticle complex modified with retro-inverso FSH peptides exhibited the strongest antitumor effects and effectively improved cisplatin sensitivity by regulating cisplatin transport proteins and increasing apoptosis through the mitochondrial pathway. Conclusions These results established HK2 as an effective therapeutic target even for cisplatin-resistant ovarian cancer and suggested a promising targeted therapeutic approach.

BackgroundLeaves of the medicinal plantAmpelopsis grossedentata, which is commonly known as vine tea, are used widely in the traditional Chinese beverage in southwest China. The leaves contain a large amount of dihydromyricetin, a compound with various biological activities. However, the transcript profiles involved in its biosynthetic pathway in this plant are unknown.ResultsWe conducted a transcriptome analysis of both young and old leaves of the vine tea plant using Illumina sequencing. Of the transcriptome datasets, a total of 52.47 million and 47.25 million clean reads were obtained from young and old leaves, respectively. Among 471,658 transcripts and 177,422 genes generated, 7768 differentially expressed genes were identified in leaves at these two stages of development. The phenylpropanoid biosynthetic pathway of vine tea was investigated according to the transcriptome profiling analysis. Most of the genes encoding phenylpropanoid biosynthesis enzymes were identified and found to be differentially expressed in different tissues and leaf stages of vine tea and also greatly contributed to the biosynthesis of dihydromyricetin in vine tea.ConclusionsTo the best of our knowledge, this is the first formal study to explore the transcriptome ofA. grossedentata.The study provides an insight into the expression patterns and differential distribution of genes related to dihydromyricetin biosynthesis in vine tea. The information may pave the way to metabolically engineering plants with higher flavonoid content.

In this study, an amidoxime-appended zirconium metal-organic framework [Zr6O4(OH)4(BDC-NHCH2CH2C(=N–OH)NH2)6](UiO-66-AO, BDC = 1,4-benzenedicarboxylate) for efficiently and rapidly removing uranium from aqueous solution was fabricated through post-modifications. The chemical structure and composition of original and modified UiO-66 MOFs were investigated in detail. The principal factors affecting the adsorption of U(VI) ions have been investigated, including pH of the aqueous solution, contact time, temperature, and coexisting cations through batch adsorption experiments. The adsorption kinetics conformed to the pseudo-second-order model. It was found that the maximum adsorption capacity reached 232.8 mg/g at pH 5.0 and 328 K based on the Langmuir isotherm. The thermodynamics parameters revealed that this adsorption process was spontaneous and endothermic. The sorption experiment in a simulated nuclear industry effluent demonstrated a high adsorption efficiency (about 95.3%) and selectivity toward uranium. The extended X-ray absorption fine structure (EXAFS) analysis revealed the coordination mechanism of amidoxime-appended UiO-66 and uranyl.

The in situ growth of one-dimensional magnetite (Fe3O4) nanowire (NW) arrays with deterministic and tunable control over their orientation and morphology on a wide range of flexible and low heat resistance substrates is still a challenge. Herein, a facile method of controlling the orientation of Fe3O4 NW arrays on a polypropylene (PP) nonwoven fabric surface (PP-g-PAO/Fe3O4) through simultaneous radiation induced graft polymerization and coprecipitation processes was realized. We demonstrated a control over the orientation and geometric properties of coprecipitated Fe3O4 NWs via complex iron ion using amidoxime groups, which not only endow the material with high durability but also lead to the oriented growth of Fe3O4 NWs. The results showed that Fe3O4 NWs were only grown on the surface of the PP nonwoven fabric (length:diameter ratio ≈ 10), whereas the Fe3O4 produced in the solution exhibited a spherical structure under identical conditions. The PP-g-PAO/Fe3O4 composite presented a good saturated magneti...

A new approach of finely tuning multinuclear clusters of metal–organic frameworks (MOFs) through symmetry-upgradingly isoreticular transformation was first presented and a bcu-type MOF, {[Cu4(μ4-O)Cl2(IN)4][CuCl2]}∞ (NJU-Bai35; NJU-Bai for Nanjing University Bai group), with cluster [Cu4(μ4-O)Cl2(COO)4N4] of higher symmetry compared to the pristine MOF, was successfully synthesized. The symmetry upgrading implemented on the inorganic part triggers the adjustment of channels in NJU-Bai35 to fit CO2 molecules, leading to a high CO2 adsorption capacity (7.20 wt % at ∼0.15 bar and 298 K) and high selectivity of CO2 over N2 and CH4 (275.8 for CO2/N2 and 11.6 for CO2/CH4) in NJU-Bai35. Breakthrough experiments further confirmed that NJU-Bai35 might be an excellent candidate for CO2 capture and natural gas purification.

By the reaction of 4,4′,4″-benzene-1,3,5-triyl-tribenzoate and magnesium nitrate in a mixture of DMA/H2O, a 2D coordination network was solvothermally synthesized. When an auxiliary ligand of acetate was introduced into the reaction system for the 2D complex, a 3D metal–organic framework was successfully obtained. The layered structure features a linear Mg3 cluster as node which is terminated by four coordinated DMA molecules. However, the DMA molecules were substituted by acetate with stronger coordination ability, resulting in an infinite Mg(COO)2 chain. Then a 3D architecture was finally formed. These two compounds also exhibit strong solid fluorescent emissions.