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Direct absorption of sunlight with carbon nanofluids is a facile way to efficiently harvest solar-thermal energy, but poor dispersion stability of nanofluids under elevated temperatures severely limits their applications. Herein, we report a general strategy to prepare stably-dispersed medium-temperature solar-thermal nanofluids by employing crumpled particles of ethanol-wetted graphene oxide sheets as the self-dispersible photothermal converters. The crumpled particles simultaneously possess intensively-deformed surface structure, a low density and a small particle size. Such features weaken the inter-particle van der Waals attraction and gravitational sedimentation of the crumpled particles, thereby enabling their long-term stable dispersion within commercial thermal storage oils. Uniform dispersion of nanofluids was maintained after continuous heating for 2 weeks under a heating temperature up to 200 °C. The homogenously dispersed nanofluids also achieved high solar absorptance with low particle loadings, and retained the large heat capacity and suitable viscosity. These combined advantageous thermophysical properties enabled consistent high-performance medium-temperature direct absorption-based nanofluidic solar-thermal energy harvesting under large-flux solar illumination.

Mesoporous graphene and other carbon derivative nanospheres have attracted intensive research attention owing to their many unique characteristics and fascinating properties. However, facile synthesis of these mesoporous nanospheres with a small particle size and controllable morphology is still a grand challenge. Herein, we report a Kirigami-inspired approach to prepare mesoporous spherical graphene oxide (MSGO) particles through spray drying of holey GO sheets. By increasing pore size and porosity of the holey GO sheets, the spray-dried particles underwent the transition from rough crumpled structure to smooth spherical shape. The prepared MSGO particles have tunable diameters smaller than 200 nm and a high specific surface area of 503 m2/g, which enable consistent high-efficiency physical adsorption removal of organic dyes such as Rhodamine B from polluted water with a high adsorption rate of 335.6 mg/(g min). Moreover, the reported synthetic route provides the freedom to easily incorporate other functional nanoparticles such as TiO2, CuO or post-dope MSGO with nitrogen elements for construction of multifunctional composite particles with tailorable structures, which may enable a broad range of promising applications.

Contact electrification (CE) has been utilized in various energy conversion systems in recent years. This work presents a constant electric energy output that was generated based on the CE at the water–metal interface. When a grounded Pt mesh is placed in water that is heated to boil, a continuous flow of electrons between the Pt mesh and the ground is generated. A possible mechanism for the generation of such electric current is based on the CE between the surface of the Pt mesh and water molecules. The local high-pressure thin liquid film regions between vapor bubbles and surface of Pt mesh promote this CE process. The constant water evaporation and bubble detachment enable the continuous electric current output. In this work, the impact of the heating temperature and the bias voltages on the generation of the current was also studied. This work provides an alternative approach to generate unidirectional current on the basis of CE at the water–metal interface, and it also offers new insights in the design of CE-based systems for the generation of electricity.

V-5Cr-5Ti alloys have been fabricated using a laser melting deposition (LMD) additive manufacturing process, showing precipitates aggregated near the grain/dendrite boundaries. Since the mechanical properties of vanadium alloys considerably depend on the precipitates, solution and aging treatments have been applied to eliminating the aggregations of the precipitates. The results show that as the solution temperature increases from 800 to 1560 °C, the densities and the lengths of the precipitates are reduced, while the widths of the precipitates are increased. When the solution temperature reaches 1560 °C, most impurity elements diffuse into the matrix and form into a nearly uniform supersaturated solid solution. Aging treatments have been applied to the 1560 °C solution treated samples. It shows that as the aging temperature increases from 800 to 1200 °C, the precipitate length increases, and the shapes of precipitates change from near-spherical to lath-like. Compared to 800 and 1200 °C, aging at 1000 °C results in the highest precipitate density. Compared to the LMD and solution-treated samples, the aged samples have the highest micro-hardness, due to the precipitation strengthening.

Carbapenem-hydrolyzing class D β-lactamases (CHDLs) are an important source of resistance to these last resort β-lactam antibiotics. OXA-48 is a member of a group of CHDLs named OXA-48-like enzymes. On the basis of sequence similarity, OXA-163 can be classified as an OXA-48-like enzyme, but it has altered substrate specificity. Compared to OXA-48, it shows impaired activity for carbapenems but displays an enhanced hydrolysis of oxyimino-cephalosporins. Here, we address the mechanistic and structural basis for carbapenem hydrolysis by OXA-48-like enzymes. Pre-steady-state kinetic analysis indicates that the rate-limiting step for OXA-48 and OXA-163 hydrolysis of carbapenems is deacylation and that the greatly reduced carbapenemase activity of OXA-163 compared to that of OXA-48 is due entirely to a slower deacylation reaction. Furthermore, our structural data indicate that the positioning of the β5-β6 loop is necessary for carbapenem hydrolysis by OXA-48. A major difference between the OXA-48 and OXA-163 complexes with carbapenems is that the 214-RIEP-217 deletion in OXA-163 creates a large opening in the active site that is absent in the OXA-48/carbapenem structures. We propose that the larger active site results in less constraint on the conformation of the 6α-hydroxyethyl group in the acyl-enzyme. The acyl-enzyme intermediate assumes multiple conformations, most of which are incompatible with rapid deacylation. Consistent with this hypothesis, molecular dynamics simulations indicate that the most stable complex is formed between OXA-48 and imipenem, which correlates with the OXA-48 hydrolysis of imipenem being the fastest observed. Furthermore, the OXA-163 complexes with imipenem and meropenem are the least stable and show significant conformational fluctuations, which correlates with the slow hydrolysis of these substrates.

Cyclopropenes carrying an alkene moiety undergo a stereoselective Alder-ene cycloisomerization under thermal conditions. Diverse functionalized (hetero)spiro[2.4]heptanes are obtained with excellent trans diastereoselectivity. According to computational studies, this thermal process takes place via transition state TS(E-exo) or TS(Z-endo) if the former is not available.

This paper reports an interfacial evaporation-driven approach for self-assembly of gold nanoparticles (AuNPs) film at the interface of liquid/air. We have designed colloidal plasmonic AuNPs capped with different types and surface coverage densities of ligands (i.e. purified and unpurified oleylamine-capped or thiol-protected AuNPs) and studied the impact of surface chemistry on the self-assembly of AuNPs by using the optically excited plasmonic heating effect. By employing the Extended Derjaguin Landau Verwey Overbeek model, the calculated lowest potential energies of assembled AuNPs capped with purified oleylamine or alkyl thiols are between -1 k_B T and -2 k_B T, which is close the room temperature thermal energy and represents meta-stable assembly, indicating the reversible self-assembly of AuNPs film observed from experiment. Furthermore, we observed superheating phenomenon in well-dispersed nanoparticles solution while normal boiling occurred in the solutions with AuNPs assemblies. The SERS activity of as-prepared AuNPs film has also been studied by using Rhodamine 6G as a molecular probe. This work not only provides a new aspect of boiling phenomena of optically heated colloidal plasmonic nanoparticle solutions, but also offers inspiration for new approach in designing surface ligands on the nanoparticles to realize reversible self-assembly via interfacial evaporation.

Ethylene glycol (EG) nanofluids have been intensively explored as one of the most promising solid-liquid phase change materials for subzero cold thermal energy storage (CTES). However, the prepared nanofluids usually suffer from a large supercooling degree, a long freezing period, reduced storage capacity and poor dispersion stability. Herein, we overcome these issues by developing stable EG nanofluids that are uniformly dispersed with low concentrations of monolayer ethanol-wetted graphene oxide nanosheets. The homogeneously dispersed monolayer sheet not only improves the thermal conductivity of the nanofluids (12.1%) but also provides the heterogeneous nucleation sites to trigger the crystal formation, thereby shortening the freezing time and reducing the supercooling degree. Compared with the base fluid, the nanofluids have reduced the supercooling degree by 87.2%, shortened the freezing time by 78.2% and maintained 98.5% of the latent heat. Moreover, the EG nanofluids have retained their initial stable homogeneous dispersion after repeated freezing/melting for 50 cycles, which ensures consistent CTES behavior during long-period operations. The facile preparation process, low loading requirement and consistent superior thermophysical properties would make the EG nanofluids loaded with monolayer graphene oxide sheets promising coolants for high-performance phase change-based CTES.

Efficient mechanism-based design of antibiotics that are not susceptible to β-lactamases is hindered by the lack of comprehensive knowledge on the energetic landscapes for the hydrolysis of various β-lactams. Herein, we adopted efficient quantum mechanics/molecular mechanics simulations to explore the acylation reaction catalyzed by CTX-M-44 (Toho-1) β-lactamase. We show that the catalytic pathways for β-lactam hydrolysis are correlated to substrate scaffolds: using Glu166 as the only general base for acylation is viable for ampicillin but prohibitive for cefalexin. The present computational workflow provides quantitative insights to facilitate the optimization of future β-lactam antibiotics.

An operationally simple and convenient synthesis method toward a series of diverse spiro[4.4]thiadiazole derivatives via double [3 + 2] 1,3-dipolar cycloaddition of nitrilimines generated in situ from hydrazonyl chlorides with carbon disulfide has been achieved under mild reaction conditions.

Glutathione S-transferases (GSTs) are multifunctional proteins that play important roles in cellular detoxification as well as in plant growth and development. Here, we cloned a new rice tau class GST gene, OsGSTU6, and evaluated its roles in regulating cadmium (Cd) stress tolerance of rice. OsGSTU6 is located both in the cytosol and nucleus of cells. The transcripts of OsGSTU6 were detected in the whole life cycle of rice with higher levels in the leaf blade and sheath at heading stage. The transcripts of OsGSTU6 were significantly stimulated by a number of environmental factors including several phytohormones, abiotic stresses, and heavy metals, suggesting its stress-responsive characteristics. Moreover, the overexpression (OE) of OsGSTU6 in rice reduced the accumulation of Cd in leaf and enhanced the tolerance of the plant to Cd stress, while knockdown (RNAi) of OsGSTU6 triggered Cd accumulation in rice leaves and decreased stress tolerance. Meanwhile, the expression levels of several candidate genes responsible for scavenging reactive oxygen species (ROS) were downregulated in OE of OsGSTU6 lines. In addition, the content of superoxide anions (O2−) and glutathione showed reduction in OE plants, but was augmented in RNAi plants under both normal growth and Cd stress, compared with wild type. Furthermore, both the yeast two-hybrid assay and firefly luciferase complementation imaging (LCI) assay demonstrated that OsGSTU6 might function with dimers in plant cells. All these results suggest that OsGSTU6 may play an important role in Cd stress tolerance of rice by involving in the intracellular ROS homeostasis.

Discovering physicochemical principles for simultaneous harvesting of multiform energy from the environment will advance current sustainable energy technologies. Here we explore photochemical phase transitions-a photochemistry-thermophysics coupled regime-for coharvesting of solar and thermal energy. In particular, we show that photon energy and ambient heat can be stored together and released on demand as high-temperature heat, enabled by room-temperature photochemical crystal↔liquid transitions of engineered molecular photoswitches. Integrating the two forms of energy in single-component molecular materials is capable of providing energy capacity beyond that of traditional solar or thermal energy storage systems based solely on molecular photoisomerization or phase change, respectively. Significantly, the ambient heat that is harvested during photochemical melting into liquid of the low-melting-point, metastable isomer can be released as high-temperature heat by recrystallization of the high-melting-point, parent isomer. This reveals that photon energy drives the upgrading of thermal energy in such a hybrid energy system. Rationally designed small-molecule azo switches achieve high gravimetric energy densities of 0.3-0.4 MJ/kg with long-term storage stability. Rechargeable solar thermal battery devices are fabricated, which upon light triggering provide gravimetric power density of about 2.7 kW/kg and temperature increases of >20 °C in ambient environment. We further show their use as deicing coatings. Our work demonstrates a new concept of energy utilization-combining solar energy and low-grade heat into higher-grade heat-which unlocks the possibility of developing sustainable energy systems powered by a combination of natural sunlight and ambient heat.

Carbonaceous and alternative supporting materials for platinum (Pt) and palladium (Pd) have been explored for the cathodic electrocatalysis in low-temperature fuel cells. Pd and Pt are widely used for catalysis owing to their remarkable electrocatalytic activity toward water splitting and fuel cell reactions. Supporting materials play a paramount role in defining electrocatalytic properties such as durability, selectivity, and activity. The conventional supporting material such as carbon black is unable to fit all the requirements under the severe operating conditions of fuel cells due to its poor corrosion resistance and limited mass transport of fuels to active catalyst sites. Nowadays the scientific research is being concentrated on devising different altered carbonic and carbon-free supporting materials for catalysts to improve the catalytic activity, stability, and selectivity of noble metal electrocatalysts. Lately, Pt, Pd and their alloy catalysts supported on modified carbonaceous and carbon-free materials have attracted solid interest owing to their prominent characteristics contributing to the remarkable fuel cell efficacy. Therefore, it is reasonable to explore this theme, regarding a variety of supporting materials, their advantages, drawbacks and future perspectives. In this mini-review, we selectively summarize recent advancements on several types of key supporting materials: carbon (graphene, carbon nanotubes, mesoporous carbon, and doped carbon nanostructures), non-carbon (transition metals oxides, borides, nitrides, and carbides) and hybrid nanocomposites.

The urgent need of catalysts with improved performances toward the hydrogen evolution reaction (HER) is still one of the crucial issues for the water splitting electrocatalysis. Herein, we exhibit ...

Drug-induced liver injury (DILI) is a widespread clinical problem. The pathophysiological mechanisms of DILI are complicated, and the traditional diagnostic methods for DILI have their limitations. Owing to its convenient operation, high sensitivity, and high specificity, luminescent sensing and imaging as an indispensable tool in biological research and clinical trials may provide an important means for DILI study. Herein, we report the rational design and preparation of a near-infrared dual-phosphorescent polymeric probe (

Differential scanning calorimetry was used to investigate the non-isothermal crystallization kinetics of the Fe76.5Nb3B20Cu0.5 glassy alloys. The nanocrystallization products and soft magnetic properties as a function of annealing temperatures were also studied by using X-ray diffractometer and vibrating sample magnetometer. The activation energies for Eg, Ex, and Ep are equal to 499 ± 3, 558 ± 7, and 693 ± 2 kJ mol−1 by Kissinger method, respectively, and 512 ± 3, 571 ± 9, and 715 ± 2 kJ mol−1 estimated by Ozawa method, respectively. The results indicate that the glass transition process is easier than the nucleation and grain growth process, while the grain growth process is much difficult than the nucleation process. The local Avrami exponent n(x) varies with the crystallized volume fraction x, indicating that the crystallization process has different crystallization mechanisms. The n(x) ranging from 1.0 to 1.2 for 0.05

To study how melatonin (MT) treatment of plants used for stubble affects the heavy metal accumulation of the subsequent crop, the effects of MT-treated Nasturtium officinale on the growth and cadmi...

Organic memory devices have recently attracted considerable interest to combat the increasing demands of data storage. Herein, taking advantage of the electron-deficient nature of iridium(III) complexes and the flexible polymer skeleton of non-conjugated polymers, a series of novel non-conjugated iridium(III) complex-containing polymers P2–P5 with non-volatile memory properties, and the corresponding model polymer P1, were rationally designed and synthesized. The memory effect of P1 is a static random-access memory type, while that of the polymers containing iridium(III) complexes are flash types. The ON/OFF current ratio of the devices based on P3 is as high as 103 and the device has good stability. It exhibits a long retention time of 104 s and both ON and OFF states, which survive up to more than 105 read cycles. The introduction of an iridium(III) complex contributes to the charge-transfer states from carbazole moieties to the iridium(III) complex, which also improves the crystallinity of polymers and realizes electrical bistability.

This paper introduces an approach to synthesize bimetallic nanoparticles under an alternating temperature field in aqueous solution. During the synthesis, pyro-catalytic barium titanate is used as the substrate to reduce the metallic ions dispersed in the solution due to the generated charges at the surface of pyro-materials under temperature oscillation. Chloroauric acid and potassium tetrachloroplatinate are used as precursors to produce gold/platinum bimetallic nanoparticles through a pyro-catalytic process. Transmission electron microscopy characterization, in combination with energy dispersive X-ray spectroscopy mapping, demonstrates that the bimetallic nanoparticle is composed of an Au core and Au/Pt alloy shell structure. Compared to the conventional approaches, the pyroelectric synthesis approach demonstrated in this work requires no toxic reducing agents and waste heat can be used as a thermal energy source in the synthesis. Hence, it offers a potential “green” synthetic method for bimetallic nanoparticles.

Two efficient novel fluorescent naphthalene and fluorene-based aromatic hydrocarbon isomers (1 and 2) are prepared and investigated for organic electroluminescence. These compounds show bright violet to deep-blue emission, narrow full width at half maximum (52 nm), and high photoluminescence efficiency (e.g. 0.61 in CH2Cl2, 0.67 in film). Alternation of substituent position on the naphthalene moiety can give rise to remarkable emission variation. The relatively large torsion angle between naphthalene and fluorene suppresses the π–π interactions by weakening the intermolecular interactions in the solid state, which can result in highly efficient fluorescence. Moreover, the 1931 Commission Internationale de L'Eclairage coordinates and maximum emission peak for deep-blue electroluminescence based on 1 are (0.16, 0.08) and 410 nm, respectively.

Stretchable electrodes have a crucial impact on the development of flexible electronic systems. Most conventionally blended nanocomposite electrodes are incapable of achieving high stretchability, breathability, or durability. In this work, a highly conductive, breathable, and stretchable epidermal electrode (SEE) is demonstrated by designing a hierarchically interactive nano-network that is composed of elastic polymer nano-fibers and multi-level silver nano-wires (AgNWs). The elastic polymer nano-fibers act as a continuous scaffold, and multi-level AgNWs embedded in the nano-fibers form branched conductive pathways. This structure enables high conductivity of the SEE at 4800 S cm-1 (at a significantly low AgNW content of 1.59 vt%), with high stretchability and excellent durability. For example, the SEE remained conductive even at a high strain of 500%, and it also maintained its initial resistance even after 30 000 cycles of strain at 50% or being washed with water for 100 000 cycles. The SEE was prepared by a facile in situ nonequilibrium fabrication process, and can easily be produced into an elastic circuit on a large scale, which provides a foundation for integrated and multifunctional electronic skins. The SEE possesses superior mechanical conformability and permeability of gas and liquid, and therefore, it was successfully applied in measuring electrocardiogram signals and thermal therapy, and exhibited highly robust and comfortable performances even while being washed with water or undergoing complex deformations.

The interaction between water and graphene oxide (GO), including water adsorption and desorption, has been widely used to demonstrate moisture-electric energy transformation (MEET). By taking advantage of water desorption stimulated by infrared (IR) light from a graphene oxide film with a gradient of oxygen-containing groups (O-group), a self-powered IR detection approach that can convert IR light into electric signals is demonstrated. The temperature sensitivity reaches 4.2 mK. With further optimization of the materials and structures, the performance of such self-powered IR detection can be further improved. The mechanism of the detection involving an IR/thermal effect on the interaction between vapor molecules and solid materials also has potential applications in thermal detection, thermal energy conversion, and chemical sensing.

The exploration of efficient yellow emitters featuring broad emission band plays an essential role for the complementary‐color‐based white organic light‐emitting devices (OLEDs). Herein, two new yellow ionic iridium(III) complexes (Ir1 and Ir2) having excellent sublimation ability are designed and prepared by the incorporation of chlorine‐modified 2‐phenylquinoline ligand and introduction of bulky counter ion. At room temperature, these ionic iridium(III) complexes show bright yellow phosphorescence in both solid and solution states due to the presence of bulky counter ion. They share the same emission wavelength (538 and 573 nm as the emission shoulder) with extremely high quantum yields (as high as 0.91) in Ar‐saturated CH2Cl2. Notably, those complexes also exhibit very broad full width at half maximum (FWHM) (up to 100 nm) attributed to almost the same intensities of emission maximum and shoulder, making them excellent candidates for white electroluminescence. The as‐prepared yellow OLEDs show high external quantum efficiency (EQE) of 11.6% and broad FWHM of 105 nm. The two‐color‐based white OLED is prepared with peak EQE of 9.2%, the 1931 CIE coordinate of (0.29, 0.31), and color rendering index of 79, proving that these new ionic iridium(III) complexes show a great potential for white electroluminescence.

Activated carbon (AC) injection is a well-proven end-of-pipe control technique for reducing polycyclic aromatic hydrocarbon (PAH) emission from flue gas. This paper introduces an effective and econ...

Allosteric regulation is a well-established phenomenon defined as a distal conformational or dynamical change of the protein upon allosteric effector binding. Here, we developed a novel approach to delineate allosteric effects in proteins. In this approach, we applied robust machine learning methods, including deep neural network and random forest, on extensive molecular dynamics (MD) simulations to distinguish otherwise similar allosteric states of proteins. Using the PDZ3 domain of PDS-95 as a model protein, we demonstrated that the allosteric effects could be represented as residue-specific properties through two-dimensional property-residue maps, which we refer to as "residue response maps". These maps were constructed through two machine learning methods and could accurately describe how different properties of various residues are affected upon allosteric perturbation on protein. Based on the "residue response maps", we propose allostery as a residue-specific concept, suggesting that all residues could be considered as allosteric residues because each residue "senses" the allosteric events through changing its single or multiple attributes in a quantitatively unique way. The "residue response maps" could be used to fingerprint a protein based on the unique patterns of residue responses upon binding events, providing a novel way to systematically describe the protein allosteric effects of each residue upon perturbation.

Electrically driven steam generation is a critical process for many heating-related applications such as sterilization and food processing. Current systems, which rely on heating up the bulk water to generate steam, face the dilemma in achieving a large evaporation flux and fast thermal response. Herein, we report a self-floating electrically driven interfacial evaporator for fast high-efficiency steam generation independent of the amount of loaded bulk water in the system. Through localized heating of the wicked water at the air–water interface, the evaporator has achieved an electrical-to-steam energy conversion efficiency of ∼90% at a heating power density of 10 kW/m2 and a fast thermal response of 20 s. The interfacial evaporation design not only achieves a high evaporation efficiency within a broad range of heating power densities by using different wicking materials, but also enables attaining a high evaporation temperature under low heating power densities by tuning the ratio of the vapor outlet area and the evaporation surface area. By integrating an interfacial evaporator within a sanitizer, the resultant system has demonstrated a faster steam temperature rise and superior steam sterilization performance than the commercial bulk heating-based approach.

In this work, the effects of lignin on the thermal stability of bagasse cellulose nanofibrils (CNFs) were investigated. The CNFs were prepared with different lignin content bagasse pulp using ultrafine grinding combined with high-pressure homogenization. Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and thermogravimetric analysis were used to study the influence mechanisms of lignin content on the thermal stability of the CNFs. The thermal stability of cellulose was tested by thermogravimetric analyzer at different heating rates, and the activation energy of bagasse cellulose nanofibrils was calculated by Flynn-Wall-Ozawa method. The results showed that the average width of CNFs prepared by the mechanical method was approximately 20 nm. The higher the lignin contents in the CNFs, the lower the crystallinity and the better the thermal stability. The thermal decomposition activation energy of CNF fluctuates with the change of conversion rate. Under the same conversion rate, the higher the lignin contents in the CNFs, the larger the activation energy value. The average activation energies of NO-LCNF, L-LCNF, ML-LCNF, MH-LCNF, and H-LCNF were 208.14, 254.49, 412.95, 530.54 and 652.10 kJ/mol, respectively, during the conversion rate of 20% to 90%. The research results provide a theoretical basis for the pyrolysis mechanism and high value utilization of CNFs and have a profound impact on promoting the application and development of CNFs in emerging nanocomposites.

In this work, bagasse pulp was used to prepare cellulose nanofibrils (CNFs) by enzymatic assisted mechanical treatment. A xylanase pretreatment was applied for varying the hemicellulose content in the pulp fibers, and the contribution of this pretreatment to the post-mechanical treatment was investigated. The results showed that CNFs prepared after xylanase pretreatment exhibited enhanced thermal stability with an increase in crystallinity. However, the overall thermal stability of the CNFs decreased significantly after xylanase was applied directly to the mechanical treated CNFs. The results indicate that the presence of hemicellulose in the fiber could affect the thermal stability of CNFs. The direct application of xylanase to CNFs could affect both the hydrogen bond between the hemicellulose and the cellulose and the covalent bond between the hemicellulose molecules, which partially destroys the internal network structure and reduces of thermal stability of CNFs.

This work explores an alternative vapor sensing mechanism through analyzing dynamic desorption process from butterfly wings for the differentiation of both individual and mixed vapors quantitatively. Morpho butterfly wings have been used in differentiating individual vapors, but it is challenging to use them for the differentiation of mixed vapor quantitatively. This paper demonstrates the use of Morpho butterfly wings for the sensitive and selective detection of closely related vapors in mixtures. Principal components analysis (PCA) is used to process the reflectance spectra of the wing scales during dynamic desorption of different vapors. With the desorption-based detection mechanism, individual vapors with different concentrations and mixed vapors with different mixing ratios can be differentiated using the butterfly wing based sensors. Both the original butterfly wings and butterfly wings with surface modification show the capability in distinguishing vapors in mixtures, which may offer a guideline for further improving selectivity and sensitivity of bioinspired sensors.

This paper demonstrates a facile solar steam generator for the generation of high-temperature steam at ambient pressure. The steam generator consists of a coiled copper tube (CCT) that serves as both solar collector and vapor heater. Both the inner and outer surfaces of the CCT are coated with black superhydrophobic copper oxide layer to improve the solar absorption, and such superhydrophobic layer prevents the condensation and clogging of water vapor during the heating process. Solar vapor is generated at the inlet of CCT through interfacial evaporation and subsequently heated inside the CCT as the vapor travels from the inlet to the outlet. By employing this approach, steam temperature that exceeds 100 °C under 1-sun illumination is demonstrated. Furthermore, steam temperature could reach as high as 250 °C under 10-sun illumination at ambient pressure. Successful sterilization experiment was also performed in this work to demonstrate the potential application of the high temperature steam generated. Such demonstrated approach helps open up the potential usage of solar-driven interfacial evaporation in applications that involve high-temperature steam, including medical sterilization, chemical manufacturing and food processing. Keywords: High-temperature steam, Photothermal conversion materials, Solar steam generation, Sterilization, Vapor heating

Photosensitizers (PSs) are of particular importance for efficient photodynamic therapy (PDT). Challenges for PSs simultaneously possessing strong light-absorbing ability, high 1O2 generation by effective intersystem crossing from the singlet to the triplet state, good water-solubility and excellent photostability still exist. Reported here are a new kind of dual-emissive semiconducting polymer nanoparticles (SPNs) containing fluorescent BODIPY derivatives and near-infrared (NIR) phosphorescent iridium(III) complexes. In the SPNs, the BODIPY units serve as the energy donors in the fluorescence resonance energy transfer (FRET) process for enhancing the light absorption of the SPNs. The NIR emissive iridium(III) complexes are chosen as the energy acceptors and efficient photosensitizers. The ionized semiconducting polymers can easily self-assemble to form hydrophilic nanoparticles and homogeneously disperse in aqueous solution. Meanwhile, the conjugated backbone of SPNs provides effective shielding for the two luminophores from photobleaching. Thus, an excellent overall performance of the SPN-based PSs has been realized and the high 1O2 yield (0.97) resulting from the synergistic effect of BODIPY units and iridium(III) complexes through the FRET process is among the best reported for PSs. In addition, owing to the phosphorescence quenching of iridium(III) complexes caused by 3O2, the SPNs can also be utilized for O2 mapping in vitro and in vivo, which assists in the evaluation of the PDT process and provides important instructions in early-stage cancer diagnosis.

A novel oxygen-bridged triarylamine polycyclic unit based tris-cyclometalated heteroleptic iridium(iii) complex (Ir-NO) has been designed and prepared. Similar iridium(iii) complexes (Ir-N and Ir-O) have also been prepared for comparison. The single crystal structure indicates that the oxygen-bridged triarylamine polycyclic unit of Ir-NO shows certain planarity, resulting in obvious rigidity and interesting π-π stacking. Additionally, Ir-NO shows a larger redshift emission (586 nm) and a longer emission lifetime (628 ns) than Ir-N (525 nm, 344 ns) and Ir-O (543 nm, 436 ns), and the phosphorescence color can be tuned from green to orange. Electrochemical experiments and DFT calculations reveal that Ir-NO exhibits a high HOMO energy level and intraligand charge transfer (3ILCT) excited state properties, which is in contrast to the low HOMO energy level and metal-to-ligand charge transfer (3MLCT) excited state properties in Ir-N and Ir-O. This result can be attributed to the strong electron-donating ability of the unit.

Direct absorption solar collectors, which use optical nanofluids to volumetrically absorb and convert sunlight into heat, have emerged as promising devices to harvest solar-thermal energy for many heat-related applications. Nanofluids, however, generally suffer from aggregation issues and the widely investigated water-based fluids only enable solar-thermal harvesting at relatively low temperatures. Herein, we report a facile way to prepare stably dispersed reduced graphene oxide-ethylene glycol (rGO-EG) fluids for solar-thermal energy harvesting at medium temperatures. Without the use of complex surface modification process, the homogeneous dispersion of rGO-EG fluids was achieved by utilizing the favorable interaction between the oxygen-containing groups on the rGO surfaces and EG molecules. The rGO-EG fluids were prepared by reducing the GO-EG fluids that are uniformly dispersed with ethanol-wetted GO through a single step of heating. The prepared rGO-EG fluids have suitable thermophysical properties for direct solar-thermal energy harvesting, such as broadband absorption of sunlight, high specific heat capacity and low viscosity. The rGO-EG fluids have shown stable uniform dispersion up to 120 °C and have demonstrated consistent solar-thermal energy harvesting performance during repeated solar radiation at ∼110 °C.

This paper presents a pyroelectric approach for the synthesis of metal–BaTiO3 hybrid nanoparticles (NPs) and demonstrates the enhanced performance on the degradation of dye solution using such hybr...

Lithium-ion batteries, with high energy density (up to 705 Wh/L) and power density (up to 10,000 W/L), exhibit high capacity and great working performance. As rechargeable batteries, lithium-ion batteries serve as power sources in various application systems. Temperature, as a critical factor, significantly impacts on the performance of lithium-ion batteries and also limits the application of lithium-ion batteries. Moreover, different temperature conditions result in different adverse effects. Accurate measurement of temperature inside lithium-ion batteries and understanding the temperature effects are important for the proper battery management. In this review, we discuss the effects of temperature to lithium-ion batteries at both low and high temperature ranges. The current approaches in monitoring the internal temperature of lithium-ion batteries via both contact and contactless processes are also discussed in the review. Keywords: Lithium-ion battery, Temperature effect, Internal temperature, Battery management, Thermal management