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Nitrate (NO3‒) pollution poses significant threats to water quality and global nitrogen cycles. Alkaline electrocatalytic NO3‒ reduction reaction (NO3RR) emerges as an attractive route for enabling NO3‒ removal and sustainable ammonia (NH3) synthesis. However, it suffers from insufficient proton (H+) supply in high pH conditions, restricting NO3‒-to-NH3 activity. Herein, we propose a halogen-mediated H+ feeding strategy to enhance the alkaline NO3RR performance. Our platform achieves near-100% NH3 Faradaic efficiency (pH = 14) with a current density of 2 A cm–2 and enables an over 99% NO3–-to-NH3 conversion efficiency. We also convert NO3‒ to high-purity NH4Cl with near-unity efficiency, suggesting a practical approach to valorizing pollutants into valuable ammonia products. Theoretical simulations and in situ experiments reveal that Cl-coordination endows a shifted d-band center of Pd atoms to construct local H+-abundant environments, through arousing dangling O-H water dissociation and fast *H desorption, for *NO intermediate hydrogenation and finally effective NO3‒-to-NH3 conversion. Alkaline nitrate electroreduction to ammonia is restricted by insufficient H+ supply. Here, the authors propose a halogen-mediated H+ feeding strategy, by triggering dangling O-H water dissociation and fast *H desorption for *NO intermediate hydrogenation, to enhance the formation of ammonia. [ABSTRACT FROM AUTHOR]

Artificial photosynthesis is a promising strategy for efficient hydrogen peroxide production, but the poor directional charge transfer from bulk to active sites restricts the overall photocatalytic efficiency. To address this, a new process of dipole field-driven spontaneous polarization in nitrogen-rich triazole-based carbon nitride (C3N5) to harness photogenerated charge kinetics for hydrogen peroxide production is constructed. Here, C3N5 achieves a hydrogen peroxide photosynthesis rate of 3809.5 µmol g−1 h−1 and a 2e− transfer selectivity of 92% under simulated sunlight and ultrasonic forces. This high performance is attributed to the introduction of rich nitrogen active sites of the triazole ring in C3N5, which brings a dipole field. This dipole field induces a spontaneous polarization field to accelerate a rapid directional electron transfer process to nitrogen active sites and therefore induces Pauling-type adsorption of oxygen through an indirect 2e− transfer pathway to form hydrogen peroxide. This innovative concept using a dipole field to harness the migration and transport of photogenerated carriers provides a new route to improve photosynthesis efficiency via structural engineering. The poor directional charge transfer from bulk to active sites restricts the overall photocatalytic efficiency. Here, the authors report a new process of dipole field-driven spontaneous polarization in nitrogen-rich triazole-based carbon nitride to harness photogenerated charge kinetics for hydrogen peroxide production. [ABSTRACT FROM AUTHOR]

In this work, we report a suitable thickening agent (cellulose nanofibril: CNF) to promote the uniformity and conductivity of silver nanowire (AgNW) transparent electrode by increasing the viscosity of AgNW ink. CNF exhibits fascinating characteristics. First, it doesn’t lower the conductivity and transmittance of film. Second, it greatly promotes the dispersity degree of AgNW in ink. Third, it doesn’t affect the ink wetting. Fourth, it increases the ink viscosity and slows the ink flow to solve the problems of disorderly ink flow and ink shrinkage. Finally, it makes the wet film dry uniformly. Hence, CNF greatly promotes the distribution uniformity of AgNW in film. As a result, with the same amount of AgNW, more conductive paths can be constructed in AgNW-CNF film to endow the film with much higher conductivity. Specifically, the sheet resistance, variation coefficient of sheet resistance, transmittance of AgNW film are 38.7 × 103 Ω/sq, 40.49%, 90.29%, while those of AgNW-CNF film are 77.5 Ω/sq, 1.59%, 91.89%. Meanwhile, although CNF doesn’t promote the adhesion force, it really greatly promotes the erasion difficulty of AgNW from the substrate. These results demonstrate that CNF and our strategy are effective. In transparent-electrode field, such suitable thickening agent is rare at present. [ABSTRACT FROM AUTHOR]

In this work, a novel deep-red (638 nm) iridium complex, Ir(bp3b)2(dend), is developed. This compound exhibits suitable physical properties for a phosphorescent emitter. First, Ir(bp3b)2(dend) and its doped film exhibit balanced charge-transporting ability. Second, methyl and pentyl groups in ligands weaken the intermolecular interaction and endow Ir(bp3b)2(dend) with good film-formation property and low concentration sensitivity. Third, short phosphorescence lifetime (1073.2 ns) indicates that it is relatively easy for triplet exciton to return to the ground state in the form of phosphorescence. Therefore, Ir(bp3b)2(dend)-doped device displays high efficiencies (8.93 cd A−1, 11.57 lm W−1, 15.63%), low roll-off of efficiencies, relatively low concentration sensitivity (from 5 to 10%), long device lifetime (T75: 11,166 h at 100 cd m−2) and very stable electroluminescent spectra (from 1 cd m−2 to maximum luminance). This performance is comparable to those of previous record deep-red (635–645 nm) phosphorescent emitters. More importantly, compared with previous record emitters, Ir(bp3b)2(dend) reports more kinds of excellent parameters. Such comprehensive deep-red phosphorescent emitter is rare at present. [ABSTRACT FROM AUTHOR]

In this paper, porphyrin-based cationic conjugated network (PCCN) nanosheets were synthesized, and its adsorption for TcO4−/ReO4− was investigated. This material was stacked with AB dislocation, with an aperture of 1.2 nm. The Re(VII)/Tc(VII) adsorption kinetics of PCCN is extremely fast, and the adsorption capacity is relatively large, the selective order is ReO4− > NO3− > Cl−. XPS and DFT revealed that the exchange of Cl− on PCCN with ReO4−, while the hydrophobic pore of PCCN are the keys to improve adsorption selectivity. It could be used to remove Tc from groundwater around nuclear facilities. [ABSTRACT FROM AUTHOR]

In this work, a novel phenanthro[9,10-d]imidazole-zinc coordination complex (Zn(TPPI)2) is reported. This compound exhibits suitable physical properties for a host material. First, its highest occupied molecular orbital (HOMO) (− 5.33 eV) energy level is favorable for hole injection from transporting layer. Second, its small singlet–triplet splitting (0.31 eV) can reduce the intrinsic energy loss from singlet to triplet excited state and promote the device efficiency. Finally, its good thermal stability (decomposition temperature: 495 °C) favors evaporation preparation of uniform films. As a result, yellow–red and red phosphorescent devices which utilize Zn(TPPI)2 as host display high efficiencies (yellow–red: 58.35 cd/A, 70.52 lm/W, 20.82%) (red: 15.89 cd/A, 16.09 lm/W and 19.05%). The performance of red device is comparable to the best results of previous publications on corresponding emitter. Meanwhile, the undoped device of Zn(TPPI)2 exhibits high efficiencies (3.79 cd/A, 3.97 lm/W, 2.47%) in zinc-complex blue emitters. These results demonstrate that Zn(TPPI)2 is a good blue emitter and host material. [ABSTRACT FROM AUTHOR]

Mesoporous carbon with high mesoporosity could overcome the diffusion limitations in the application fields requiring fast mass transportation. However, traditional templating approaches-derived carbons usually own low mesoporosity resulted from the microporosity dominated nanostructure. Herein, we developed a versatile method adopting self-made Fe(OH)3 as coordinative template to absorb phenols by coordination effect and in situ inducing the polymerization of phenol and formaldehyde to form phenolic resin at Fe(OH)3. Then, the generated H2O and the derived iron oxide from the template upon high temperature could serve as activation regents and mold constructing rich mesoporosity and graphitic structure. The derived products possess foam-like morphology, worm-like mesoporous structure, good graphitization degree, large surface area (1590 m2/g), large pore volume (2.86 cm3/g), uniform pore size distribution (~ 3.1 nm), ultrahigh mesoporosity (98.6%) and exhibit an excellent energy storage performance for aqueous supercapacitor including large energy density of 30.6 Wh/kg, superior capacitance retention of 76.8% and long cycling stability with near 100% capacitance retention after 10 000 cycles at large current density of 20 A/g. The superior capacitance retention for SC implies a wide application potentiality of the developed mesoporous carbon in other fields closely related to fast mass transfer such as catalysis, sorption and so on. [ABSTRACT FROM AUTHOR]

Surface damage has great influence on optical properties, especially the laser-induced damage threshold of optics, and it has become a difficult and basic issue to find suitable methods to efficiently remove the surface damage for improving the surface quality. In this paper, the characteristic evolution of brittle scratch and ground/lapped surface damage during inductively coupled plasma etching (ICPE) process are experimentally investigated on fused silica. Results of damage removal tests show ICPE can efficiently remove brittle scratch and eliminate the lateral and medial cracks. The PV (peak to valley) and RMS (root mean square) values of surface roughness increase with the exposure of lateral and medial cracks, and then gradually decreases with further etching. Finally, the ground and lapped fused silica surfaces with a size of 300 × 300 × 20 mm3 are efficiently processed by ICPE. The power spectral density analysis further demonstrates that the damage can be efficiently removed by ICPE. This study reveals the damage evolution during ICPE process and also provides technical guidance for optimizing the efficient damage removal process to rapidly improve surface quality, precision and fabrication efficiency of fused silica optics. [ABSTRACT FROM AUTHOR]

Because of its high sensitivity to misalignment, precision grinding of free-form surfaces with micron accuracy requires accurate registration of the surface measurement point cloud. Registration of point clouds obtained with a coordinate measuring machine (CMM) is generally an iterative process of finding optimal coordinate transformation between the CMM frame and the model frame of the workpiece by minimizing the point-to-surface distances with probe radius compensation. For free-form surfaces, frequent calculation of point-to-surface distances consumes very much time, and a trade-off has to be made between the efficiency and the accuracy. This paper presents a method for fast registration of free-form surface point clouds based on the point-to-triangle distance which involves only Delaunay triangulation of a two-dimensional dataset, and the surface normal is quickly calculated from cross product. Probe radius compensation is realized by registering the probe center points with the offset surface. We prove that it is equivalent to registering the probe contact points with the nominal surface through theoretical analysis. The registration problem is then formulated as sequential linear least-square problems with properly defined ball constraints. To validate the method, numerical simulations are presented to show the accuracy of the point-to-triangle distance. The registration algorithm also shows excellent robustness against misalignment of tens of millimeters/degrees. Finally measurement, registration, and grinding of a free-form optical surface are experimentally demonstrated. The surface error obtained after registration is used for compensatory grinding which reduces it to micron level. [ABSTRACT FROM AUTHOR]

With the development of new materials and ultra-precision processing technology, the sizes of measured objects increase, and the requirements for machining accuracy and surface quality become more exacting. The traditional measurement method based on reference datum is inadequate for measuring a high-precision object when the quality of the reference datum is approximately within the same order as that of the object. Self-referenced measurement techniques provide an effective means when the direct reference-based method cannot satisfy the required measurement or calibration accuracy. This paper discusses the reconstruction algorithms for self-referenced measurement and connects lateral shearing interferometry and multi-probe error separation. In lateral shearing interferometry, the reconstruction algorithms are generally categorized into modal or zonal methods. The multi-probe error separation techniques for straightness measurement are broadly divided into two-point and three-point methods. The common features of the lateral shearing interferometry method and the multi-probe error separation method are identified. We conclude that the reconstruction principle in lateral shearing interferometry is similar to the two-point method in error separation on the condition that no yaw error exists. This similarity may provide a basis or inspiration for the development of both classes of methods. [ABSTRACT FROM AUTHOR]

Silver nanowires without particles are synthesized by a solvothermal method at temperature 150 °C. Silver nanowires are prepared via a reducing agent of glycerol and a capping agent of polyvinylpyrrolidone ( M ≈ 1,300,000). Both of them can improve the purity of the as-prepared silver nanowires. With controllable shapes and sizes, silver nanowires are grown continuously up to 10-20 μm in length with 40-50 nm in diameter. To improve the yield of silver nanowires, the different concentrations of AgNO synthesis silver nanowires are discussed. The characterizations of the synthesized silver nanowires are analyzed by UV-visible absorption spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscope (AFM), and silver nanowires are pumped on the cellulose membrane and heated stress on the PET. Then, the cellulose membrane is dissolved by the steam of acetone to prepare flexible transparent conducting thin film, which is detected 89.9 of transmittance and 58 Ω/□. Additionally, there is a close loop connected by the thin film, a blue LED, a pair of batteries, and a number of wires, to determinate directly the film if conductive or not. [ABSTRACT FROM AUTHOR]

According to forming principle of line contact spherical generating by cup-shaped wheel, the sources of grinding error were analyzed, and a new method for error analysis and compensation was proposed in this paper. In a certain grinding condition, the grinding error caused by the pose errors between wheel and workpiece was simulated, the corresponding curve fitting of grinding error was carried out, and an appropriate parametric model was established. If the actual grinding error is known, the model can identify the corresponding pose error as well as compensate the grinding error. The simulation and experiment processes of compensation validate the efficient and workability of parametric model, and improve the grinding precision. [ABSTRACT FROM AUTHOR]

A series of novel molecules with a cyclen (1,4,7,10-tetraazacyclododecane) moiety appended on and bearing different aromatic fragments in the structures were synthesized and characterized. The binding activities of these compounds towards DNA were systematically studied by spectroscopic, viscometric and gel electrophoresis methods. The results suggest that the stacking interaction plays an important role in improving the DNA binding ability of the compounds. The binding modes of the compounds towards DNA are also affected by the sizes of the aromatic rings. The binding interaction between binaphthyl compound 1b and several nucleosides was studied by fluorescence titration. Stacking interaction and hydrophobic interaction play the key role in such non-selective binding process. [ABSTRACT FROM AUTHOR]

Although numerous fluorescent probes are designed to detect the pH value in the past decades, developing fluorescent probes for extreme alkalinity (pH > 14) detection in aqueous solution is still a great challenge. In this work, we utilized 1H-imidazo[4,5-f][1, 10] phenanthroline (IP) group as the recognition group of hydroxyl ion and introduced two triethylene glycol monomethyl ether groups to improve its solubility. This IP derivative, BMIP, possessed good solubility (25 mg/mL) in water. It displayed high selectivity toward extreme alkalinity (pH > 14) over other ions and pH (from extreme acidity to pH = 14). From 3 to 6 mol/L OHˉ, the exact concentration of OHˉ could be revealed by BMIP and the whole detection process just needed a short time (≤ 10 s). Meanwhile, it exhibited good anti-interference ability and repeatability during the detection process. Through optical spectra and NMR analysis, its detection mechanism was proved to be deprotonation by hydroxyl ion and then aggregation-induced enhanced emission. Our study presents a new basic group based on which researchers can develop new fluorescent probes that can detect extreme alkalinity (pH > 14) in aqueous solution. [ABSTRACT FROM AUTHOR]

Conjugated polymers (CPs)-based near-infrared phototheranostics are receiving increasing attention due to their high molar extinction coefficient, wide emission wavelength, easy preparation and excellent biocompatibility. Herein, several new conjugated polymers with D2-D1-A structures were easily prepared through one-pot coupling using triphenylamine (D2) as well as thiophenes (D1) as electron donors and benzothiadiazole (A) as electron acceptors. Interesting, their optical performance and power conversion efficiency could be tuned by side chains on thiophenes (D1). The introduction of ethylenedioxy into D1 as side chain significantly improves fluorescence imaging brightness, photothermal conversion efficiency and hydrophilicity, and extends emission wavelength, which are beneficial for phototheranostic. The side chain modification provides new opportunity to design efficient phototheranostics without construction new fluorescent skeletons. [ABSTRACT FROM AUTHOR]

In this paper, porphyrin-based cationic conjugated network (PCCN) nanosheets were synthesized, and its adsorption for TcO4−/ReO4− was investigated. This material was stacked with AB dislocation, with an aperture of 1.2 nm. The Re(VII)/Tc(VII) adsorption kinetics of PCCN is extremely fast, and the adsorption capacity is relatively large, the selective order is ReO4− > NO3− > Cl−. XPS and DFT revealed that the exchange of Cl− on PCCN with ReO4−, while the hydrophobic pore of PCCN are the keys to improve adsorption selectivity. It could be used to remove Tc from groundwater around nuclear facilities. [ABSTRACT FROM AUTHOR]