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Crystalline porous materials sustained by supramolecular interactions (e.g., π–π stacking interactions) are a type of molecular crystals showing considerable stability, but their applications are rarely reported due to the high difficulty of their construction. Herein, a stable π–π stacking framework formed by a trinuclear copper(I) compound [Cu3(HBtz)3(Btz)Cl2] (CuBtz, HBtz = benzotriazole) with pyrazolate-bridged dicopper(I) sites is reported and employed for electrochemical CO2reduction, showing an impressive performance of 73.7 ± 2.8% Faradaic efficiency for C2+products [i.e.,ethylene (44%), ethanol (21%), acetate (4.7%), and propanol (4%)] with a current density of 7.9 mA cm–2at the potential of −1.3 V versusRHE in an H-type cell and a Faradic efficiency (61.6%) of C2+products with a current density of ≈1 A cm–2and a reaction rate of 5639 μmol m–2s–1at the potential of −1.6 V versusRHE in a flow cell device, representing an impressive performance reported to date. In-situinfrared spectroscopy, density functional theory calculations, and control experiments revealed that the uncoordinated nitrogen atoms of benzotriazolates in the immediate vicinity can act as proton relays and cooperate with the dicopper(I) site to promote the hydrogenation process of the *CO intermediate and the C–C coupling, resulting in the highly selective electroreduction of CO2to C2+products.

C19H20O8, triclinic, P1‾$P\overline{1}$(no. 2), a= 7.0708(4) Å, b= 8.1261(4) Å, c= 16.1067(6) Å, α= 81.252(4)°, β= 81.500(4)°, γ= 77.890(4)°, V= 887.88(8) Å3, Z= 2, Rgt(F) = 0.0418, wRref(F2) = 0.1158, T = 150 K.

Efficiently converting CO2and H2O into value-added chemicals using solar energy is a viable approach to address global warming and the energy crisis. However, achieving artificial photocatalytic CO2reduction using H2O as the reductant poses challenges is due to the difficulty in efficient cooperation among multiple functional moieties. Metal-organic frameworks (MOFs) are promising candidates for overall CO2photoreduction due to their large surface area, diverse active sites, and excellent tailorability. In this study, we designed a metal-organic framework photocatalyst, named PCN-224(Zn)-Bpy(Ru), by integrating photoactive Zn(II)-porphyrin and Ru(II)-bipyridyl moieties. In comparison, two isostructural MOFs just with either Zn(II)-porphyrin or Ru(II)-bipyridyl moiety, namely PCN-224-Bpy(Ru) and PCN-224(Zn)-Bpy were also synthesized. As a result, PCN-224(Zn)-Bpy(Ru) exhibited the highest photocatalytic conversion rate of CO2to CO, with a production rate of 7.6 μmol·g−1·h−1in a mixed solvent of CH3CN and H2O, without the need for co-catalysts, photosensitizers, or sacrificial agents. Mass spectrometer analysis detected the signals of 13CO (m/z= 29), 13C18O (m/z= 31), 16O18O (m/z= 34), and 18O2(m/z= 36), confirming that CO2and H2O acted as the carbon and oxygen sources for CO and O2, respectively, thereby confirming the coupling of photocatalytic CO2reduction with H2O oxidation. In contrast, using PCN-224-Bpy(Ru) or PCN-224(Zn)-Bpy as catalysts under the same conditions resulted in significantly lower CO production rates of only 1.5 and 0 μmol·g−1·h−1, respectively. Mechanistic studies revealed that the lowest unoccupied molecular orbital (LUMO) potential of PCN-224(Zn)-Bpy(Ru) is more negative than the redox potentials of CO2/CO, and the highest occupied molecular orbital (HOMO) potential is more positive than that of H2O/O2, satisfying the thermodynamic requirements for overall photocatalytic CO2reduction. In comparison, the HOMO potential of PCN-224(Zn)-Bpy without Ru(II)-bipyridyl moieties is less positive than that of H2O/O2, indicating that the Ru(II)-bipyridyl moiety is thermodynamically necessary for CO2reduction coupled with H2O oxidation. Additionally, photoluminescence spectroscopy revealed that the fluorescence of PCN-224(Zn)-Bpy(Ru) was almost completely quenched, and a longer average photoluminescence lifetime compared to PCN-224(Zn)-Bpy and PCN-224-Bpy(Ru) was observed. These suggest a low recombination rate of photogenerated carriers in PCN-224(Zn)-Bpy(Ru), which also supported by the higher photocurrent observed in PCN-224(Zn)-Bpy(Ru) compared to PCN-224(Zn)-Bpy and PCN-224-Bpy(Ru). In summary, the integrated Zn(II)-porphyrin and Ru(II)-bipyridyl moieties in PCN-224(Zn)-Bpy(Ru) play important roles of a photosensitizer and CO2reduction as well as H2O oxidation sites, and their efficient cooperation optimizes the band structure, thereby facilitating the coupling of CO2reduction with H2O oxidation and resulting in high-performance artificial photocatalytic CO2reduction.

The prevalence of food allergies has grown dramatically over the past decade. Recently, studies have shown the potential of marine substances to alleviate food allergies. We utilized a rat basophilic leukemia (RBL)-2H3 model to evaluate the antiallergic effects of alternariol monomethyl ether (AME) extracted from marine fungi Alternaria sp. Our results showed that AME attenuated food allergy symptoms in mice and reduced histamine release in serum. The population of mast cells in the spleen and mesenteric lymph nodes was considerably reduced. Moreover, in vitroassays also revealed that AME inhibited the release of β-hexosaminidase and histamine. Transcriptomic analysis uncovered that AME regulated gene expression associated with mast cells. Additionally, Western blotting demonstrated that AME suppressed mast cell activation by modulating MAPK and NF-κB signaling pathways. Taken together, these findings provide a theoretical basis for the potential antiallergic use of marine-derived compounds in the development of functional foods.

A novel and high efficient PbO2 electrode has been fabricated in the present study for refractory wastewater treatment. The traditional Ti plate is made into honeycomb by electronic corrosion to be used as electrode basement. The novel surface topography improves the specific surface area of the electrode material and enhances the adhesion of surface coating. SnO2-Sb layer is deposited between basement and PbO2 layer which reduces the thermal stress and improve electrode life. Rare earth element La is doping into PbO2 layer to improve the lattice structure and the catalytic performance. Finally, F ion is adding into the catalytic layer to improve the smoothness of the material surface. Characterized by SEM and XRD, results showed that the electrode prepared has novel surface morphology. Pollutants degradation results and electrode life test showed that the PbO2 electrode investigated in the present study has great advantage compared with traditional electrodes and has good application prospect.

Monodisperse nickel phosphide (Ni5P4) nanoparticles supported on carbon (Ni5P4@C) were in situ synthesized by one step solution-phase route, in which the mixture of trioctyloxide (TOPO) and trioctylphosphine (TOP) was used as solvent, capping agent and phosphor source. Ni5P4nanocrystals were in situ coupled by active carbon simply adding the carbon to the reaction solution. The as-prepared Pt-free Ni5P4 nanocrystals exhibit the enhanced electrocatalytic activity toward hydrogen oxidation reaction (HOR) compared to pure commercial Ni nanoparticles. Therefore, the obtained Ni5P4@C nanocatalyst appears to be promising non precious metal electrocatalysts for HOR.

The automotive emission has become the main source of the air pollution in cities. How to remove NOx effectively is the key and difficult point in the control of automobile exhaust. In this work, sol-gel was applied to prepare NOx purification catalyst, LaCoO3 which was doped with strontium (Sr) and iron (Fe). The average particle size was less than 25 nm. The optimum composition of doped LaCoO3 was determined as La0.8Sr0.2Co0.95Fe0.05O3 with a minimum particle size, 14.3nm. The denitrification rate of La0.8Sr0.2Co0.95Fe0.05O3 increased by 27.9% compared with that of LaCoO3. It was noted that the sample powder would agglomerate when doped LaCoO3 was calcinated at 800°C, the calcination temperature of LaCoO3. Therefore the calcination temperature for double doped LaCoO3 was optimized. According to results of XRD and BET, the optimum calcination temperature of La0.8Sr0.2Co0.95Fe0.05O3 is 575°C, which not only overcame the agglomeration but also reduced the particle size to 11.2nm. The denitrification rate of La0.8Sr0.2Co0.95Fe0.05O3 calcinated at 575°C is up to 95.8% which is higher 38.7% than that of it calcinated at 800 °C.

A major challenge in chemical engineering is the separation and purification of materials, especially of rare earth compounds. It has been reported that a dielectrophoretic (DEP) apparatus can be used for separating rare earth oxides. The DEP capture of REOs on screen electrode was observed with microscope. The concentration of ROEs was determined using a nephelometer and ICP-OES before and after injection into the DEP apparatus. The results show that three types of REOs, La2O3, CeO2 and Dy2O3, generate nDEP in the DEP capture apparatus. There are two factors: voltage and suspension concentration, that affect the capture rate. The capture rate increases as voltage rises within certain limits. The capture rate also increases with increase in the original suspension concentration. Different REOs show marked differences in the DEP capture conditions. Consequently, factors such as voltage and flow rate can be controlled to achieve separation of different REOs.

To investigate the influences of TimeSlips on the Cornell Scale for Depression in Dementia (CSDD) scores of mild or moderate senile dementia patients.

Hydrogen zeolite was modified with CeO2 by impregnation - filtration - heat treatment. Hydrogen-zeolite samples before and after modification were characterized by XRD and SEM. The catalytic efficiency of modified hydrogen-zeolite was investigated. Such modification conditions were explored: as the CeO2 percentage, calcination temperature, calcination time, impregnation temperature. The results show that the optimal CeO2 percentage is 0.5%, calcination temperature is 600°C, calcination time is 2h, impregnation temperature is 75°C. The aspirin yield reaches 78.3% under the optimal conditions, compared with that (64.8%) catalyzed by sulfuric acid and that (70.4%) catalyzed by unmodified zeolite. XRD, SEM characterizations show that Ce ions can be doped into the zeolite framework. And the modification makes the zeolite particle size become smaller, which is reduced to 50.5nm from 56.76nm. A high efficient and eco-enviromently catalyst was got by modification.

One lanthanide nitrate (Ln = Tb) with a novel three dimensional structure have been prepared through hydrothermal method. Single crystal X-ray diffraction structures were obtained. The compound crystallizes in the orthorhombic, Pnma space group. The lanthanide ions are eight-coordinate with six oxygen atoms coming from nitrate ions and two from bridge oxygen atoms. If the bridge oxygen atoms could be ignored, the compound can be described as a rare microporous 3D Lanthanide nitride with the open framework.

In the present study, catalyst of SO42-/ZrO2-TiO2-SiO2-Al2O3 has been prepared by sol-gel method and doped by Y, La and Chitosan, respectively. The catalytic ability of modified catalysts for the synthesis of hexyl butyrate has been tested. It has been shown that the catalytic ability has been improved obviously after modification. Under the best experimental conditions, with Y doping 1%, La doped 1.5% and Chitosan doped 4%, the catalytic ability has been improved from 76.7% to 90.7%, 92.1% and 93.9%. Characterized by XRD, SEM and IR, it has been found that the grain sizes of catalysts are smaller which due to higher specific surface andimprove the catalytic ability. With abundant amino groups at the surface, the Chitosan doping improves the capacity of SO42- for catalysts.

In this paper, silica microspheres and several novel μm scale DEP (dielectrophoresis) micro electrode array chips were prepared. A DEP experimental system was assembled to investigate the the DEP response of silica microspheres and micrometer particles. The effects of pattern of electrodes and frequency of AC field on the manipulation of silica microspheres were analyzed. The results showed that silica microspheres were manipulated by negative DEP (nDEP) in all types of electrodes, the position of silica microspheres in the electrodes changed when the frequency was changed and the phenomenon of nDEP was more obvious at higher frequency. A gas sensor was fabricated by dielectrophoretically assembling SiO2 micrometer particles. The sensor showed good response to SO2 and NH3 gas. The measurement results confirmed DEP could be a quicker method for constructing gas sensor.

Silk fabric was first developed in ancient China, and Chinese silk also promoted the first world large-scale commercial exchanges between the East and the West. Digital printing is a technical breakthrough in the field of traditional printing and dyeing industry, which can also improve the value of the silk. There is a long history of making books by silk, and the recent revival of silk books also put forward new demands to digital printing. There exist two methods for printing book, both of which have their disadvantages. We propose a fast digital printing method for silk book which combines the advantages of the previous two methods. As the silk book has become a new choice for book collection, we believe that the proposed method will largely accelerate the popularity of silk book.

Considering the influence of communication constraints and uncertain short delay, this paper models NCS with communication sequence as a discrete periodical switching system with uncertainty, which integrates information scheduling and control. Using the method of piecewise Lyapunov function and the switching system theory, the asymptotic stability condition of the system with periodical information scheduling is derived in the form of matrix inequalities, and a output feedback controller design method is derived.

Several rare earth phosphate nanomaterials have been synthesized. It is shown that during the Micro emulsion preparation process, the size and morphology of rare earth phosphate nanomaterials could be tuned by changing the conditions of the micro emulsion system, which have a significant effect on the fluorescence properties.

This paper presents a device to investigate dielectrophoresis (DEP) effects through different patterns of the electrodes. Pattern of electrodes, DEP time and voltage have been described to research the manipulation of particles by dielectrophoresis. The TiO2 sample droplet was dropped onto several electrode pairs using a micro-dropper. We succeeded in manipulating TiO2 particles along the electric field and deposited them across the gaps between two electrodes by modulating different factors. SEM images were used to confirm the patterns of different electrodes.

A new photorefractive composite based on a bifunctional methacrylate copolymer with N-methacryloxypropyl-3-(p-nitrophenyl)azo carbazole and N-methacryloxypropyl carbazole as pendant side chains, which has high stability and potential applications, was synthesized. A two-beam coupling gain coefficient of 9.4 cm⁻¹ and an electrooptic coefficient of 9.3 pm/V were measured at the applied electric field of 92.4 V/μm by a typical two-beam coupling experiment and a compensation electrooptic measurement technique. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 189–194, 2000

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) was successfully applied to characterize the organosilver coordinative cluster compounds, silver phenylacetylide and three silver thiolates, namely, silver tertiary butylthiolate, silver 2,6-dimethylbenzenethiolate, and silver 2,6-dichlorobenzenethiolate. Samples and dithranol matrix were finely dispersed in 1:1 tetrahydrofuran (THF)/chloroform (CHCl3) mixed solvent. In most cases the monomer units remained intact during ionization, and the oligomeric molecular ions were produced through silver cationization, with a general molecular ion formula [nM + Ag]⁺. This was further verified by the relative abundances of the isotopic peaks within the molecular ion clusters, which were in close agreement with those theoretically calculated for nM cationized with one silver ion. In the case of silver 2,6-dichlorobenzenethiolate, in addition to the dominant [nM + Ag]⁺ peaks, weak peaks corresponding to the successive losses of hydrogen chloride molecules were observed. Copyright © 2000 John Wiley & Sons, Ltd.

Ethylcellulose microcapsules containing theophylline were prepared by the O/W emulsion non-solvent addition method. Toluene-cyclohexane was chosen as a solvent-non-solvent pair. The effect of the non-solvent added to the polymer solution on the properties of microcapsules was investigated. The results indicated that the size distribution and drug content of microcapsules were slightly affected by the amount of non-solvent in polymer solution. However, the internal conformation of microcapsules was directly related to the amount of non-solvent added to the polymer solution. The greater the non-solvent to solvent ratio in polymer solution the larger the percentage of microcapsules having a hollow conformation. Dissolution studies showed that the release rate of theophylline from microcapsules increased with increasing amount of non-solvent added to the polymer solution, but the release pattern of microcapsules was not obviously changed.

A new technique in which ethylcellulose microcapsules containing theophylline (a water-soluble drug), prepared using the O/W emulsion non-solvent addition method, was developed. Toluene-cyclohexane was chosen as the solvent-nonsolvent system. The effects of four process variables, polymer concentration, species and concentration of emulsifier, and core to wall ratio, on the micromeritic properties and release behaviour of microcapsules were investigated. The results indicated that theophylline can be microencapsulated with a high yield (low drug loss) by using the O/W emulsion non-solvent addition method with the toluene-cyclohexane system. The particle size and drug content of the microcapsules were influenced by these process variables. The morphology of microcapsules was also affected by the core to wall ratio. The release pattern of the microcapsules was found to have similar properties to the release of a drug from a spherical homogeneous matrix. The effective diffusion coefficient increased with increasing core to wall ratio.