•Cesium removal from tap waters using Prussian blue non-woven fabric was studied.•The maximum adsorption capacities of cesium with fabric were estimated.•The column tests with high-turbidity real raw ...waters were conducted.•All PB treatments led to quality tap water with high cesium removals.
Cesium (Cs) removal from tap waters is an emerging issue after the Fukushima Daiichi Nuclear Power Plant Disaster. Adsorbents highly specific to Cs in the presence of other alkali and alkali earth metals are desired to supply safe drinking waters to residents near the contaminated area. This work for the first time used Prussian blue (PB) nanoparticles implemented non-woven fabric as an efficient adsorbent for Cs removal. Adsorption isotherms were obtained using Langmuir equation at 288, 298 and 308K, from which the maximum adsorption capacities were estimated as 216, 241, 260mg/g. The studied PB-Cs adsorption was endothermic process while its capacity was lower in acid than in alkaline solutions. The column tests with synthetic raw water and pilot plant column with low and high-turbidity real raw waters revealed almost complete removal of Cs by sufficiently long contact time. All PB treatments had no noticeable effects on water quality while the produced water had no biological acute toxicities. Use of PB non-woven fabric for decontaminating Cs pollution in drinking water was discussed.
Bioinspired smart materials with synergistic allochroic luminescence and complex deformation are expected to play an important role in many areas of science and technology. However, it is still ...challenging to fabricate such soft actuators with high programmability that can be manipulated in situ with high spatial resolution. Herein, we have incorporated terminally functionalized aggregation‐induced emission active tetraphenylethene derivative and photochromic spiropyran moieties into the networks of liquid crystal elastomers through covalent bonding to obtain the synergistic photochromic luminescence and programmable soft actuators. Bio‐mimic functions and light‐induced auxetic metamaterial‐like devices were shown to be feasible based on the combination of assembly and origami‐programming strategy. These bioinspired devices with synergistic photochromic luminescence and complex photodeformation abilities provide an elegant strategy to design multi‐functional liquid crystal actuators.
Inspired by the synergic allochroic and shape‐morphing bio‐functions like caterpillars and cephalopods, photochromic luminescent liquid crystal actuators were prepared. Complex movements and fluorescent colors can be synergically manipulated by light based on the phase transition of liquid crystals and photoresponse of the fluorescent chromophores after the actuators were programmed with hybrid mesogenic alignments.
•A total of 31 cold-formed steel elliptical hollow section T-joint tests with three different member orientations were conducted.•The specimens were tested with the chord simply supported and the ...brace axially compressed.•The load-carrying capacities, load-deformation responses and failure modes are presented.•Feasibility of current design methods were examined.•The predictions are quite conservative and scattered for cold-formed steel elliptical hollow section T-joints.
A test campaign on cold-formed steel elliptical hollow section T-joints with the chord simply supported and the brace axially compressed is described in this paper. Four different sizes of elliptical hollow sections with the section aspect ratio ranged from 1.65 to 3 were employed to fabricate the T-joint specimens. Thirty-one T-joint specimens with three different types of member orientations were considered. Robotic gas metal arc welding was adopted to fabricate the elliptical hollow section T-joint specimens. The width ratio between brace and chord (β) ranged from 0.29 to 1. The brace-to-chord thickness ratio (τ) ranged from 0.60 to 1.77 and the chord width-to-thickness ratio (2γ) ranged from 10.6 to 52.3. All the T-joint specimens were tested with the chord simply supported and the brace axially compressed. The load-carrying capacities, load-deformation responses and failure modes of the elliptical hollow section T-joints are presented and discussed. Since no codified design provision is available for elliptical hollow section T-joints investigated herein, the feasibility of the design provisions originally developed for tubular T-joints with conventional cross-sections (i.e. circular hollow section and rectangular hollow section) as specified in the CIDECT and Eurocode 3 as well as the design recommendations proposed for hot-rolled steel elliptical joints was examined. Comparison results indicate that the joint strength predictions via these design methods are quite conservative and scattered for cold-formed steel elliptical hollow section T-joints.
Overcoming the resistance to apoptosis and immunosuppression of tumor cells is a significant challenge in augmenting the effect of cancer immunotherapy. Pyroptosis, a lytic programmed cell‐death ...pathway unlike apoptosis, is considered a type of immunogenic cell death (ICD) that can intensify the ICD process in tumor cells, releasing dramatically increased tumor‐associated antigens and damage‐associated molecular patterns to promote cancer immunotherapy. Herein, a tumor cell membrane‐targeted aggregation‐induced emission photosensitive dimer is found to be able to achieve highly efficient ICD under the synergistic effect of photodynamic and photothermal therapy. The photosensitive dimer can efficiently produce type‐I reactive oxygen species (ROS) by photodynamic therapy in hypoxic tumor tissue, leading to pyroptosis by direct cell membrane damage, which is further reinforced by its photothermal effect. Furthermore, the enhanced ICD effect based on the dimer can completely eliminate the primary tumor on the seventh day of treatment and can also boost systemic antitumor immunity by generating immune memory, which is demonstrated by the superior antitumor therapeutic effects on both solid tumors and metastatic tumors when healing 4T1 tumor mouse models with poor immunogenicity.
A membrane‐targeted photosensitive dimer, which effectively generates type‐I reactive oxygen species in hypoxic tumor tissue for pyroptosis‐mediated photoimmunotherapy, is successfully developed. Its remarkable photothermal properties accelerate the pyroptosis process, increase DNA damage in tumor cells, generate drastic immunogenic cell death and systemic antitumor immune response, and prevent tumor recurrence and metastasis.
Light‐harvesting systems are an important way for capturing, transferring and utilizing light energy. It remains a key challenge to develop highly efficient artificial light‐harvesting systems. ...Herein, we report a supramolecular co‐assembly based on lower‐rim dodecyl‐modified sulfonatocalix4arene (SC4AD) and naphthyl‐1,8‐diphenyl pyridinium derivative (NPS) as a light‐harvesting platform. NPS as a donor shows significant aggregation induced emission enhancement (AIEE) after assembling with SC4AD. Upon introduction of Nile blue (NiB) as an acceptor into the NPS‐SC4AD co‐assembly, the light‐harvesting system becomes near‐infrared (NIR) emissive (675 nm). Importantly, the NIR emitting NPS‐SC4AD‐NiB system exhibits an ultrahigh antenna effect (33.1) at a high donor/acceptor ratio (250:1). By co‐staining PC‐3 cells with a Golgi staining reagent, NBD C6‐ceramide, NIR imaging in the Golgi apparatus has been demonstrated using these NIR emissive nanoparticles.
Combined harvester: Supramolecular co‐assembly of lower‐rim dodecyl‐modified sulfonatocalix4arene (SC4AD) and naphthyl‐1,8‐diphenyl pyridinium derivatives (NPS) gives a light‐harvesting platform showing significant aggregation induced emission enhancement (AIEE). By using these near‐infrared (NIR) emissive nanoparticles imaging in the Golgi apparatus is possible.
This paper attempts to acquire fundamental knowledge on the mechanical properties of high strength steels and the corresponding high strength weld metals at arctic low temperatures. Two types of high ...strength steels (Q890, Q960) and three types of high strength weld metals (made of ER100S-G, ER110S-G, ER120S-G feedstock wires) were tested at arctic low and ambient temperatures ranging from −75 °C to 25 °C. Tensile coupon specimens for steel materials were directly extracted from high strength steel plates, whilst robotic gas metal arc welding was employed to fabricate the tensile specimens of weld metals. The tensile coupon specimens were designed as per ASTM E8M and wire-cut into shapes. Twenty-three tensile coupon tests on high strength steels and eighteen tensile coupon tests on high strength weld metals were carried out. Coupon specimens were tested in liquid nitrogen cooling chamber to mimic the arctic low temperature environment. The stress–strain responses and key mechanical properties of high strength steels and weld metals at both ambient and arctic low temperatures are presented and discussed. Prediction equations for key mechanical properties, including the Young’s modulus, yield stress and ultimate tensile strength, of high strength steels and weld metals at arctic low temperatures were proposed.
•Low temperature mechanical properties of Q890 and Q960 high strength steels as well as high strength weld metals made of different feedstock wires were investigated.•The tensile specimens were exposed to arctic low temperatures of −20 °C, −40 °C, −60 °C and −75 °C.•Static stress–strain curves were used to determine low temperature mechanical properties and retention factors.•Accurate empirical prediction equations were proposed to determine low temperature mechanical properties of high strength steels and weld metals.
Abstract
Dissipative self-assembly, which requires a continuous supply of fuel to maintain the assembled states far from equilibrium, is the foundation of biological systems. Among a variety of ...fuels, light, the original fuel of natural dissipative self-assembly, is fundamentally important but remains a challenge to introduce into artificial dissipative self-assemblies. Here, we report an artificial dissipative self-assembly system that is constructed from light-induced amphiphiles. Such dissipative supramolecular assembly is easily performed using protonated sulfonato-merocyanine and chitosan based molecular and macromolecular components in water. Light irradiation induces the assembly of supramolecular nanoparticles, which spontaneously disassemble in the dark due to thermal back relaxation of the molecular switch. Owing to the presence of light-induced amphiphiles and the thermal dissociation mechanism, the lifetimes of these transient supramolecular nanoparticles are highly sensitive to temperature and light power and range from several minutes to hours. By incorporating various fluorophores into transient supramolecular nanoparticles, the processes of aggregation-induced emission and aggregation-caused quenching, along with periodic variations in fluorescent color over time, have been demonstrated. Transient supramolecular assemblies, which act as fluorescence modulators, can also function in human hepatocellular cancer cells.
Recombinant subunit vaccines should contain minimal non-pathogen motifs to reduce potential off-target reactivity. We recently developed a vaccine antigen against respiratory syncytial virus (RSV), ...which comprised the fusion (F) glycoprotein stabilized in its pre-fusion trimeric conformation by "DS-Cav1" mutations and by an appended C-terminal trimerization motif or "foldon" from T4-bacteriophage fibritin. Here we investigate the creation of a cysteine zipper to allow for the removal of the phage foldon, while maintaining the immunogenicity of the parent DS-Cav1+foldon antigen. Constructs without foldon yielded RSV F monomers, and enzymatic removal of the phage foldon from pre-fusion F trimers resulted in their dissociation into monomers. Because the native C terminus of the pre-fusion RSV F ectodomain encompasses a viral trimeric coiled-coil, we explored whether introduction of cysteine residues capable of forming inter-protomer disulfides might allow for stable trimers. Structural modeling indicated the introduced cysteines to form disulfide "rings", with each ring comprising a different set of inward facing residues of the coiled-coil. Three sets of rings could be placed within the native RSV F coiled-coil, and additional rings could be added by duplicating portions of the coiled-coil. High levels of neutralizing activity in mice, equivalent to that of the parent DS-Cav1+foldon antigen, were elicited by a 4-ring stabilized RSV F trimer with no foldon. Structure-based alteration of a viral coiled-coil to create a cysteine zipper thus allows a phage trimerization motif to be removed from a candidate vaccine antigen.
A two‐stage mediated near‐infrared (NIR) emissive supramolecular assembly for lysosome‐targeted cell imaging is presented. 4,4′‐Anthracene‐9,10‐diylbis(ethene‐2,1‐diyl))bis(1‐ethylpyridin‐1‐ium) ...bromide (ENDT) was synthesized as an organic dye with weak fluorescence emission at 625 nm. When ENDT complexes with cucurbit8uril (CB8), this binary supramolecular complex assembles into nanorods with a near‐infrared fluorescence emission (655 nm) and fluorescence enhancement as the first stage. Such supramolecular complexes interact with lower‐rim dodecyl‐modified sulfonatocalix4arene (SC4AD) to form nanoparticles for further fluorescence enhancement as the second stage. Furthermore, based on a co‐staining experiment with LysoTracker Blue, such nanoparticles can be applied in NIR lysosome‐targeted cell imaging.
Supramolecular assemblies were designed with initially weak 625 nm near‐IR emission that was enhanced and shifted to 655 nm in two stages by cucurbit8uril (CB8) and amphiphilic calixarene SC4AD. This system was used for lysosome‐targeted cell imaging.
•Numerical analyses on cold-formed steel EHS under combined compression and minor axis bending were conducted.•Accurate finite element model was developed and validated with available test ...results.•560 beam-columns and 112 column counterparts were included in the parametric study.•Experimental and numerical data were compared with the predictions by current design methods.•Modified design methods are proposed with improved accuracy of design strength predictions.
This paper aims to study the structural performance and design of cold-formed steel elliptical hollow sections under combined compression and minor axis bending. An accurate finite element model was developed and validated against the available test results. The validated model was further used to carry out an extensive parametric study on 560 beam-columns, including fifty-six cross-section series with two different specimen lengths loaded at five different eccentricities, and 112 concentric loaded column counterparts. A broad range of cross-section geometries and a spectrum of member slenderness and loading eccentricities were designed for the parametric study. A total of 602 beam-column results, including 42 available test data and 560 numerical results in this study was compared with the predictions by the existing design methods, such as the equivalent diameter method and the equivalent rectangular hollow section approach with the European Code as well as the existing traditional design rules (Australian Standard, North American and American Specifications) using equivalent diameter. Reliability analysis was also carried out. It is shown that the existing design methods provide quite conservative and scattered design strength predictions. In this study, modifications are proposed on the Australian Standard, North American and American Specifications, which are proven to provide accurate and reliable design predictions. Among the three modified design methods, it is recommended to use the modified ANSI/AISC360 method for the design of cold-formed steel elliptical hollow sections under combined compression and minor axis bending as it provides the most accurate predictions in this study.
PDF
