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The emerging water purification technology represented by solar water evaporation has developed rapidly in recent years and is widely used in seawater desalination. However, the high reflectivity of sunlight and low efficiency of photothermal conversion greatly hinder its application prospects. In this paper, the hierarchical structure of the film was designed and optimized by the addition of carbon materials in the process of bacterial cellulose culture. A cellulose-based composite film material with a microporous structure was obtained, which can improve the photothermal evaporation rate and photothermal conversion efficiency from the structural principle to improve the stability of floating on the water. Bacterial cellulose (BC) as a three-dimensional carrier was combined with one-dimensional and two-dimensional (1D/2D) compounds of carbon nanotubes (CNT) and reduced graphene oxide (RGO) to form composite films for solar evaporation. By the addition of CNT-RGO (21.8 wt %), the composite showed prominent photothermal evaporation rate and photothermal conversion efficiency properties. Through in situ culture of BC, not only a tight structure can be obtained but also the surface of BC contains a large number of hydroxyl groups, which have many active sites to load photothermal materials. BC nanofibers, CNT, and RGO cooperate to form a porous network structure, which provides continuous double channels for the rapid transmission of water molecules and light paths, so as to form an excellent photothermal layer. The photothermal conversion efficiency is 90.2%, and the photothermal evaporation rate is 1.85 kg m

Ionic conductors such as polymer electrolytes and ionic liquids have high thermoelectric voltages several orders of magnitude higher than electronic thermoelectric materials, while their conductivity is much lower than the latter. This work reports a novel approach to achieve high-performance ionic conductors using calcium ion (Casup2+/sup) coordinated bacterial cellulose (CaBC) through molecular channel engineering. Through the coordination of Casup2+/supwith cellulose molecular chain, the distance between the cellulose molecular chains is widened, so that ions can transport along the cellulose molecular chain. Therefore, we reported ionic thermoelectric (i-TE) material based on CaBC/NaCl with a relatively high ionic Seebeck coefficient of -27.2 mV Ksup-1/supand high ionic conductivity of 204.2 mS cmsup-1/sup. This ionic hydrogel is promising in the design of high-thermopower i-TE materials for low-grade heat energy harvesting.

Developing FeOOH as a robust electrocatalyst for high output oxygen evolution reaction (OER) remains challenging due to its low conductivity and dissolvability in alkaline conditions. Herein, it is demonstrated that the robust and high output Zn doped NiOOH-FeOOH (Zn-Fe

Two novel 1,3-bis[tris(hydroxymethyl)methylamino]propane (H6L) functionalized 3d-4f heterometallic arsenotungstates (ATs) [H2N(CH3)2]5Na2H4[Cu(H2L)]{[Ln0.5Na1.5Cu3(H2O)5](AsW9O33)2}·17H2O [Ln = HoIII (1), YbIII (2)] have been synthesized in conventional aqueous solution by using simple materials and further characterized by elemental analyses, IR spectra, thermogravimetric analyses, powder X-ray diffraction spectra and single-crystal X-ray diffraction. The most prominent structural feature of 1 and 2 is that two trivacant Keggin [B-α-AsW9O33]9− subunits sandwich an opening pentagonal metallocycle heterometallic cluster [Cu(H2L)Ln0.5Na1.5Cu3(H2O)5]7+ with the copper-organic group [Cu(H2L)]2−. The UV absorption spectra illustrate that 1 is stable in the pH range of 2.48–8.02. The solid-state electrochemical properties of 1 have also been measured in 0.5 mol·L−1 H2SO4/Na2SO4 aqueous solution by entrapping it in a glass carbon electrode. Furthermore, the variable-temperature magnetic susceptibility of 1 shows the weak CuII − HoIII ferromagnetic interactions.

Herein, a porous heddle of poly(vinyl butyral) (PVB) was successfully prepared by thermally induced phase separation with PEG400. A phase diagram of PVB was presented, and the effects of various parameters, such as polymer concentration, extrusion temperature, quenching temperature and take-up speed, on the morphology and properties of the PVB porous heddle were investigated. The pore size and porosity of the heddle increase as the extrusion temperature increases. Furthermore, upon increasing the quenching temperature during the TIPS process, the pore size and mechanical properties decrease, whereas porosity increases. In addition, due to the substantially unchanged crystallinity of the PVB heddle, the tensile strength increases since porosity decreases with the increasing take-up speed. The porosity of the prepared PVB porous heddle reached up to 74.63% when the PVB concentration, the quenching temperature and the extrusion temperature were 20 wt%, 0 °C and 170 °C, respectively. Thus, this porous heddle exhibiting a biconnected structure and significant mechanical properties is promising in the field of porous carrier materials.

The facile one-step assembly reaction of Na2WO4·2H2O, Sn(CH3)2Cl2, RE(NO3)3·6H2O and K2TeO3 in the presence of dimethylamine hydrochloride as an organic solubilizing agent in acidic aqueous solution resulted in a family of dimethyltin-functionalized rare-earth (RE) incorporated tellurotungstates consisting of {B-α-TeW7O28} and {W5O18} mixed building units [H2N(CH3)2]8Na4H2[RE2(OH)(B-α-TeW7O28)Sn2(CH3)4(W5O18)]2·18H2O [RE = ErIII (1), YbIII (2), HoIII (3), YIII (4)]. The most striking structural characteristic of 1–4 is that they all contain a novel tetrameric S-shaped [RE2(OH)(B-α-TeW7O28)Sn2(CH3)4(W5O18)]214– moiety simultaneously including two pentavacant Keggin [B-α-TeW7O28]12– and two monovacant Lindqvist [W5O18]6– fragments connected by RE and dimethyltin linkers. To the best of our knowledge, such dimethyltin-functionalized RE-containing tellurotungstates have not been reported before. The visible or NIR solid-state emission spectra of 1 and 3 display the characteristic emission bands arising from E...

Two 1-D organic–inorganic hybrid phosphotungstates based on Dawson subunits and lanthanide complexes [Ln(DMF)6(H2O)][Ln(DMF)4(H2O)4][α-P2W18O62]·2H2O (Ln3 + = Ce3 + for 1, Nd3 + for 2) (DMF = dimethylformamide) were synthesized in aqueous solution and further characterized by elemental analyses, IR spectra, thermogravimetric analyses and single-crystal X-ray diffraction. It is the most prominent feature of 1 and 2 that adjacent [α-P2W18O62]6 − polyoxoanions are linked by [Ln(DMF)6(H2O)]3 + cations to form a 1-D infinitely zigzag chain and the 1-D chains are aligned in an –ABAB– fashion in the bc plane. In addition, the [Ln(DMF)4(H2O)4]3 + cation only grafts to the “cap” site of the [α-P2W18O62]6 − polyoxoanion by a terminal oxygen atom. Besides, the solid-state fluorescence properties and lifetime decay behavior of 2 in the near-infrared region have also been investigated in detail.

Heterostructure engineering carries prime importance to enhance the catalytic activity of electrocatalysts for water splitting. However, developing nonprecious metal oxides as splendid bifunctional electrocatalysts in alkaline conditions remains a great challenge. Herein, we developed a smart soaking strategy of sulfur/iron ion modification, by which we could activate Co3O4 to spontaneously form heterogeneous structure with excellent hydrogen/oxygen evolution reaction (HER/OER) performance. The nickel foam supported Co3O4 nanoarrays embellished with NiCoSx (NiCoSx@Co3O4 NAs/NF) was easily obtained via sulfur ion modification, which has rich oxygen vacancies and active sites, leading to an outstanding HER performance (η10 = 59 mV, η400 = 264.0 mV). Furthermore, Fe(Ⅱ) ion modified NiCoSx@Co3O4 NAs/NF (FeNiCoS@Co3O4 NAs/NF) achieved superior OER performance (η10 = 226 mV, η400 = 302 mV) than other recently reported cobalt-based catalysts due to the synergistic activity of Ni-Fe-S-Co. More importantly, this work offered a facile and energy-free strategy for developing transition metal oxides as splendid bifunctional catalysts and contributed to the cost and energy savings and mass production for industrial applications as well as the design of advanced functional materials for energy chemistry.

For large-scale implementation of electrochemical hydrogen production, it is essential to develop electrocatalysts that work well at high current densities over a wide pH range. Herein, we use a facile method to synthesize a hierarchical bimetal phosphide (CoP@Ni2P) on nickel foam, which requires very low overpotentials to achieve the benchmark 10 mA cm−2 (e.g., 16 mV in alkaline media). Furthermore, the CoP@Ni2P can deliver a high current density of 500 mA cm−2 at small overpotentials and show no obvious decay after the durability test for over 48 h at all pH levels. The outstanding catalytic performance is attributed to the superaerophobicity of the electrode surface, fast electron transport as well as the increased number of exposed active sites caused by the hierarchical structure and the synergistic effect of the heterostructures. Consequently, this work provides an advanced transition metal-based phosphide for large-scale hydrogen production in all pH ranges.

Two series of novel organic–inorganic hybrid carboxylated rare-earth-substituted monolacunary Dawson-type phosphotungstate monomers [Hdap]4[RE(H2O)(Hpic)3][RE(Hpic)2 (α2-P2W17O61)]·21H2O [RE = GdIII (1), TbIII (2), DyIII (3), HoIII (4), ErIII (5), TmIII (6), YbIII (7), YIII (8); Hpic = 2-picolinic acid, dap = 1,2-diaminopropane] and dimers [H2dap]8[RE2(H2ox)2(ox)(α2-P2W17O61)2]·25H2O [RE = HoIII (9), ErIII (10), TmIII (11), YbIII (12), YIII (13); H2ox = oxalic acid] have been hydrothermally synthesized and characterized by elemental analyses, IR spectra, thermogravimetric measurements, and X-ray single-crystal diffraction. The monomeric polyoxoanion skeleton of isomorphic 1–8 is constructed from a monolacunary Dawson-type phosphotungstate implanted by a [RE1(Hpic)2]3+ cation in the polar position and supported by the other [RE2(H2O)(Hpic)3]3+ cation on the equatorial belt. Interestingly, two kinds of RE cations separately coordinate to two or three Hpic ligands in the form of N–C–C–O–RE containing five-me...

In this work, we study the use of decision tree-based models to predict the transfer rates in different parts of the data pipeline that sends experiment data from Linac Coherent Light Source (LCLS) at SLAC National Accelerator Laboratory (SLAC) to National Energy Research Scientific Computing Center (NERSC). The system monitoring the data pipeline collects a number of characteristics such as the file size, source file system, start time and so on, all of which are known at the start of the file transfer. However, these static variables do not capture the dynamic information such as current state of the networking system. In this work, we explore a number of different ways to capture the state of the network and other dynamic information. We find that in addition to using static features, using these dynamic features can improve the transfer performance predictions by up to 10-15%. We additionally study a couple of different well-known decision-tree based models and find that Gradient-Tree Boosting algorithm performs better overall.

Herein, a porous heddle of poly(vinyl butyral) (PVB) was successfully prepared by thermally induced phase separation with PEG400. A phase diagram of PVB was presented, and the effects of various parameters, such as polymer concentration, extrusion temperature, quenching temperature and take-up speed, on the morphology and properties of the PVB porous heddle were investigated. The pore size and porosity of the heddle increase as the extrusion temperature increases. Furthermore, upon increasing the quenching temperature during the TIPS process, the pore size and mechanical properties decrease, whereas porosity increases. In addition, due to the substantially unchanged crystallinity of the PVB heddle, the tensile strength increases since porosity decreases with the increasing take-up speed. The porosity of the prepared PVB porous heddle reached up to 74.63% when the PVB concentration, the quenching temperature and the extrusion temperature were 20 wt%, 0 °C and 170 °C, respectively. Thus, this porous heddle exhibiting a biconnected structure and significant mechanical properties is promising in the field of porous carrier materials.

Converting CO2 into renewable solar fuel using photocatalysts is one of the most ideal solutions for environmental challenges and energy crises. Here, the solid-solid Z-scheme Zn0.5Cd0.5S/Au@g-C3N4 (ZCS/Au@CN) heterojunction showed improved photocatalytic reduction of CO2 due to the enhanced visible light consumption, fast dissolution of photogenerated electron-hole pairs, quick interfacial transfer process of electrons, and enlarged surface area. Under visible-light irradiation, methanol (CH3OH) was produced at a rate of 1.31 μmol h−1 g−1 over ZCS/Au@CN, roughly 43.6 and 32.7 folds higher than those observed over pure ZCS and CN samples. The analytical characterization results verified the role of AuNPs as an electron mediator, which improved the rapid extraction of photoinduced electrons and enhanced the reduction ability of CO2. This work not only demonstrates a facile photodeposition assisted hydrothermal method for fabrication of ZnxCd1-xS/Au@C3N4 heterojunction composite photocatalysts but also demonstrates the possibility of utilizing ternary composites for enhanced photocatalytic reduction of CO2.

Human respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract disease in young children. With repeat infections throughout life, it can also cause substantial disease in the elderly and in adults with compromised cardiac, pulmonary and immune systems. RSV is a pleomorphic enveloped RNA virus in the Pneumoviridae family. Recently, the three-dimensional (3D) structure of purified RSV particles has been elucidated, revealing three distinct morphological categories: spherical, asymmetric, and filamentous. However, the native 3D structure of RSV particles associated with or released from infected cells has yet to be investigated. In this study, we have established an optimized system for studying RSV structure by imaging RSV-infected cells on transmission electron microscopy (TEM) grids by cryo-electron tomography (cryo-ET). Our results demonstrate that RSV is filamentous across several virus strains and cell lines by cryo-ET, cryo-immuno EM, and thin section TEM techniques. The viral filament length varies from 0.5 to 12 &mu, m and the average filament diameter is approximately 130 nm. Taking advantage of the whole cell tomography technique, we have resolved various stages of RSV assembly. Collectively, our results can facilitate the understanding of viral morphogenesis in RSV and other pleomorphic enveloped viruses.