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In this work, a Pdx/C-TiO2/g-C3N4-yphotocatalyst was synthesized by combining g-C3N4with Ti3C2through heat treatment, followed by loading with noble metal Pd. Morphological characterization and XPS before and after reaction revealed the formation of a C-TiO2/g-C3N4Z-scheme heterojunction system with Pd deposited on top. The optimal catalyst, Pd0.8/C-TiO2/g-C3N4-5, exhibited significantly enhanced total C1 yields under mild conditions, achieving 6.1 and 2.6 times the yields of g-C3N4and C-TiO2, respectively. Notably, the HCHO yield was improved to 3854.79 μmol·g–1·h–1. Mechanistic studies indicated that the C-TiO2/g-C3N4heterojunction significantly enhanced the CH4conversion performance by effectively suppressing photogenerated charge recombination. Additionally, the loaded Pd promoted CH4adsorption and activity, further improving the CH4conversion efficiency. Furthermore, Pd contributed to the high C1 yield by accelerating the generation of both and •OH radicals.

In this paper, N-doped TiO2mixed crystals are prepared via direct calcination of TiN for highly selective oxidation of CH4to HCHO at room temperature. The structures of the prepared TiO2samples are characterized to be N-doped TiO2of anatase and rutile mixed crystals. The crystal structures of TiO2samples are determined by XRD spectra and Raman spectra, while N doping is demonstrated by TEM mapping, ONH inorganic element analysis, and high-resolution XPS results. Significantly, the production rate of HCHO is as high as 23.5 mmol·g−1·h−1with a selectivity over 90%. Mechanism studies reveal that H2O is the main oxygen source and acts through the formation of ·OH. DFT calculations indicate that the construction of a mixed crystal structure and N-doping modification mainly act by increasing the adsorption capacity of H2O. An efficient photocatalyst was prepared by us to convert CH4to HCHO with high yield and selectivity, greatly promoting the development of the photocatalytic CH4conversion study.

A novel rod-shaped MIL-88A(Fe)/BiOI heterojunction composite is fabricated by an in-suit chemical deposition method for visible-light-assisted peroxymonosulfate activation to eliminate AR18 (acid red 18). A series of x%MIL-88A(Fe)/BiOI are obtained according to the mass ratio of MIL-88A(Fe) to BiOI. Among them, 30 %MIL-88A(Fe)/BiOI could remove 97.79 % AR18 within 40 minutes. The reaction parameters on this process are investigated, such as PMS concentration, catalyst dosage, initial pH and dye concentration. The optimal conditions are determined to be [catalyst]= 1 g·L−1, [PMS]=1 mM, pH=7.02. The scavenging experiments and EPR analysis manifest that 1O2is the main active species for AR18 degradation. In accordance with the band structure, active species, XPS, PL, EIS and photocurrent response, the Z-scheme electron transfer path of the composite catalyst is proved under 500 W (λ > 420 nm) Xenon lamp irradiation. In the end, the stability and universality of the composite catalyst in practical application are evaluated by three cyclic tests and inorganic anion experiments. This work provides valuable guidance for synthesizing efficient and stable MOF based heterojunction photocatalysts.

Ammonia is closely relevant to human production and life. Although the widely used conventional Haber–Bosch process has a relatively high ammonia yield, it has obvious disadvantages of high energy consumption, serious pollution, and harsh reaction conditions. Compared with the Haber–Bosch process, photo- and electrocatalytic N2fixation has been demonstrated to be energy-saving, environmentally friendly, and economical because the ammonia can be generated under mild conditions. During the photo/electrocatalytic ammonia-production processes, sunlight or electricity is used as the renewable energy input, the atmosphere is used as the nitrogen source, and water is used as the proton source. However, the ammonia yields of the photo- and electrocatalytic nitrogen fixation are commonly low, which is mainly resulted by the lack of active sites to adsorb N2molecules and active N≡N triple bonds. On the basis of the discussion about the importance of active sites for ammonia synthesis by summarizing the reaction mechanism of photo- and electrocatalytic methods, we outline the common methods of producing abundant active sites of N2adsorption and activation on the surface of catalysts, including vacancy introduction, heteroatom doping, cocatalyst support, and frustrated Lewis pairs construction. We also summarize the detection methods of ammonia, as well as other problems existing during the photo- and electrocatalytic nitrogen-fixation processes.

As one of the most promising photoanode candidates for photoelectrochemical (PEC) water splitting, the photocurrent density of BiVO4still needs to be further improved in order to meet the practical application. In this work, a highly-matched BiVO4/WO3nanobowl (NB) photoanode was constructed to enhance charge separation at the interface of the junction. Upon further modification of the BiVO4/WO3NB surface by NiOOH/FeOOH as an oxygen evolution cocatalyst (OEC) layer, a high photocurrent density of 3.05 mA cm−2at 1.23 V vs.RHE has been achieved, which is about 5-fold higher than pristine BiVO4in neutral medium under AM 1.5 G illumination. 5 times higher IPCE at 450 nm is also achieved compared with the BiVO4photoanode, leading to about 95% faradaic efficiency for both H2and O2gas production. Systematic studies attribute the significantly enhanced PEC performance to the smaller BiVO4particle size (< 90 nm) than its hole diffusion length (~100 nm), the improved charge separation of BiVO4by the single layer WO3nanobowl array and the function of OEC layers. Such WO3NB possesses much smaller interface resistance with the substrate FTO glass and larger contact area with BiVO4nanoparticles. This approach provides new insights to design and fabricate BiVO4-based heterojunction photoanode for higher PEC water splitting performance.

Free silver ions (Ag+) in the solution exhibit enhanced photocatalytic dechlorination processes of organic chloride, including 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-DCP) and 2,4,6-trichlorophenol (2,4,6-TCP), over copper phenylacetylene (PhC2Cu) under visible light irradiation. The concentration of AgNO3remarkably affects the dechlorination activity of PhC2Cu. With the optimal concentration of 2 mM AgNO3, PhC2Cu showed the best photocatalytic performance, and the dechlorination rate of PhC2Cu was 2.3-fold enhanced under visible light irradiation for 80 minutes. This deep mechanism study demonstrated that free Ag+in the solution, but not the deposited Ag particles on the surface of PhC2Cu, plays the most imported role in promoting the photocatalytic dechlorination process by forming the insoluble salt of AgCl.

We anchored Ph–CC–Cu, a type of metal organic molecule, onto the surface of α-Bi2O3nanoparticles (NPs) to efficiently eliminate a high concentration of methyl orange (MO) in waste water. With the optimal α-Bi2O3/Ph–CC–Cu hybrid, the degradable concentration of MO was 3 × 10−4M, which is 5 times higher than that in most of the previously reported photocatalytic researches (6 × 10−5M). The photocatalytic activity of the α-Bi2O3/Ph–CC–Cu hybrid in this work even exceeds that of commercial P25 for MO degradation under full spectrum light. Furthermore, a targeted Z-scheme construction was proposed and demonstrated using photocatalytically generated reactive oxygen species (ROS), photocurrent densities, fluorescence spectra and photocatalytic reduction of AgNO3experiment. This work not only reported an efficient hybrid for MO elimination with high concentration in waste water, but also provided new explanations for the Z-scheme mechanism.

In this work, iron doping was proposed to improve the photo(electro)catalytic activity of PhC2Cu, an air stable metal–organic coordination polymeric photocatalyst. After displacement of partial Cu atoms by Fe, the energy band structure of PhC2Cu was successively modulated, featuring a narrowed band gap and down-shift in the valence band towards a more positive potential. More interestingly, the luminescence chromism upon iron doping is indicative of inhibited ligand-to-metal charge transfer (LMCT) that is relevant to the recombination of photocarriers. When the mole ratio of Fe/Cu reached 2%, the photocurrent density achieved its maximum, which was 4 times higher than that of the PhC2Cu photocathode, consistent with an enhanced separation of electron–hole pairs. Furthermore, the extremely negative conduction band potential of PhC2Cu enabled efficient O2activation, generating a series of reactive oxygen species (ROS) for the degradation of organic pollutants. The rate of methyl orange (MO) and 2,4-dichlorophenol (2,4-DCP) degradation over 2% Fe–PhC2Cu increased by 2 and 1.6 times. This study provides a promising strategy for improving the activity of metal–organic photocatalysts.

Electro-, photo-, and photoelectrocatalysis play a critical role toward the realization of a sustainable energy economy. They facilitate numerous redox reactions in energy storage and conversion systems, enabling the production of chemical feedstock and clean fuels from abundant resources like water, carbon dioxide, and nitrogen. One major obstacle for their large-scale implementation is the scarcity of cost-effective, durable, and efficient catalysts. A family of two-dimensional transition metal carbides, nitrides, and carbonitrides (MXenes) has recently emerged as promising earth-abundant candidates for large-area catalytic energy storage and conversion due to their unique properties of hydrophilicity, high metallic conductivity, and ease of production by solution processing. To take full advantage of these desirable properties, MXenes have been combined with other materials to form MXene hybrids with significantly enhanced catalytic performances beyond the sum of their individual components. MXene hybridization tunes the electronic structure toward optimal binding of redox active species to improve intrinsic activity while increasing the density and accessibility of active sites. This review outlines recent strategies in the design of MXene hybrids for industrially relevant electrocatalytic, photocatalytic, and photoelectrocatalytic applications such as water splitting, metal–air/sulfur batteries, carbon dioxide reduction, and nitrogen reduction. By clarifying the roles of individual material components in the MXene hybrids, we provide design strategies to synergistically couple MXenes with associated materials for highly efficient and durable catalytic applications. We conclude by highlighting key gaps in the current understanding of MXene hybrids to guide future MXene hybrid designs in catalytic energy storage and conversion applications.

This work describes the synthesis of C@BiOBr using glucose as the carbon precursor by a repeatable one-step hydrothermal method. Characterization studies indicate that the structure of BiOBr did not change after the carbon layer was encapsulated on the surface. The highest activity is achieved at 1.2-C@BiOBr, with 97% of phenol (50 mg·L-1) degrading within 90 min, and the degradation amount of phenol is determined to be 48.5 mg·g–1with a speed of 0.54 mg·g–1·min–1. The useful species of phenol degradation are studied and assigned to •O2–, 1O2, and h+. The effect of coated carbon layer for photocatalytic degradation of phenol over BiOBr is studied by photoelectrochemical experiments, fluorescence spectra, and density functional theory (DFT) calculations. It is attributed to the good conductivity of carbon, enhanced separation of the photocarriers by carbon coating, and thermodynamically favorable reactive oxygen species (ROS) production on the surface of carbon. This work demonstrates that carbon coating is an effective strategy to improve the photocatalytic activity of BiOBr and reveals the detailed mechanism.

For the better utilization of solar light and complete oxidation of environmental organic pollutants, it is desired to develop small band gap semiconductors with a deep valence band as efficient visible light photocatalysts. In this work, we prepared the fluorinated Bi2O3 catalysts using a precipitation method, followed by a solvethermal process in the presence of NH4F. The fluorinated Bi2O3 catalysts, especially with the atomic ratio of F to Bi (RF) at 0.2, exhibit much higher photocatalytic activities than the pure Bi2O3 for the degradation of methyl orange (MO) under the visible light irradiation. The effects of the fluorination on the phase structure, special surface areas, morphologies, optical properties, surface-adsorbed species, and electronic band structure of the Bi2O3 were investigated in details. It was revealed that both the surface-adsorbed and lattice-substituted fluorine, induced by the fluorination to Bi2O3, play critical roles in the enhanced photocatalytic performance of the fluorinated Bi2O3. The two types of fluorine species effectively inhibit the recombination of the photo-excited electron-hole pairs by withdrawing the photo-excited electrons, and increase the oxidation power of the photo-excited hole by lowering the valence band edge, respectively.

A series of 6-bromo-2,3-dioxoindolin phenylacetamide derivatives was synthesized and evaluated for inhibitory activity against CDC25B and PTP1B. Most of the synthesized compounds showed potential inhibitory activities for CDC25B and PTP1B with compound 12 being the most potent (IC50=3.87 μmol/L and 2.98 μmol/L, respectively). Compound 12 also exhibited higher cytotoxic activity against three cancer cell lines (HeLa, A549 and HCT116). In addition, compound 12 delayed the potent tumor inhibitory activity in a colo205 xenograft model in vivo.

To enhance the ber performance of pseudo physical-layer network coding (ppnc) scheme, a new scheme called pseudo physical-layer soft network coding (ppsnc) scheme is proposed, ppsnc adopts soft information not hard decision information, and its ber performance is better than ppnc. Meanwhile ppsnc has no synchronization problem compared with physical-layer network coding (pnc) scheme. At the same time, we also discuss the performance of ppsnc in mimo environment. The simulation results show that mimo-ppsnc outperforms the other schemes.

As the primary link and the accepting link of power supply and sale, the quality of business expansion is directly related to the economic benefits and social profile of the power company. By many measures, such as reducing the link of process and delayering business expansion process, realizing multi link synchronous operation and integrally operating all qualified links, the process of high voltage business expansion project is optimized. The practice proves that these measures effectively reduce the average time of power access, and improve the level of power supply service. Keywords: power supply company; business expanding; process optimization; average power access time

Many underground structures have witnessed great damage in recent earthquakes. Thus underground structures in earthquake prone zones should be designed to withstand both static overburden loads and earthquake loads. In this paper, different closed form solutions for the analysis of the tunnel response, are considered as developed on the basis of the theory that the stress increment due to seismic loading can be assessed through a correct estimate of free-field deformation, while the internal forces of tunnel linings subjected to overburden loads can also be estimated through an assumption of far-field stress using the developed solutions. Numerical studies have been performed to validate the available analytical solutions.

The dependence of Au adhesion and photocatalytic performance on the support’s exposed facets in the Au/TiO2system is an important consideration in the design of Au/TiO2heterogeneous catalysts. In this article, we prepared anatase TiO2single crystals with different percentages of exposed {101} and {001} facets by a hydrothermal process. The uniform deposition of crystalline metallic Au nanoparticles with the mean diameter of 10 to 11 nm onto both exposed {101} and {001} facets of the prepared anatase TiO2single crystals has been achieved with the aid of power ultrasound. The Au-deposited TiO2single crystals with the dominant {001} facet have been demonstrated to have much higher plasmon-induced photocatalytic activity than those with the dominant {101} facet for the degradation of 2,4-dichlorophenol. It was revealed that the dominant facet of anatase TiO2crystal plays a critical role in the plasmon-induced photocatalytic performance of Au/TiO2system. The {001} facet enhances the efficiency of the interfacial charge-transfer process by offering a stronger adherence for Au nanoparticles than the {101} facet, which promotes the generation of the reactive oxygen species O2•–by the plasmon-induced electron transfer from Au nanoparticles to anatase TiO2substrate. This work would provide useful guidance for the design of Au/TiO2heterogeneous photocatalysts.

A high-performance liquid chromatographic method (HPLC) with evaporative light scattering detection (ELSD) has been developed for fingerprint analysis of Flos Lonicerae. The samples were separated with an Agilent C18 column using acetonitrile (A) and 0.1% formic acid solution under gradient conditions (0→10 min：11.5%→15% A, 10→12 min：15% →22% A, 12→18min：22%→33% A; 18→30min: 33%→45% A) as the mobile phase at a flow rate of 0.8ml min−1 within 30 min. The ELSD conditions were optimized at nebulizer-gas flow rate 2.7 L min−1 and drift tube temperature 105℃. Precision experiments showed relative standard deviation (R.S.D.) of peak area and retention time were better than 2.5%, inter-day and intra-day variabilities showed that R.S.D. was ranged from 0.66% to 4.17%. Accuracy validation showed that average recovery was between 95.33% and 104.10%. The method was validated to achieve the satisfactory precision and recovery. Relative retention time and relative peak area were used to identify the common peaks for fingerprint analysis. There are nine common peaks in the fingerprint. The quality of sixteen batches of Flos Lonicerae samples was evaluated by hierarchical clustering analysis, which classfied all bacthes into two clusters. Furthermore, the contents of important medicinal compounds (chlorogenic acid, macranthoidin B and dipsacoside B) in different batches of Flos Lonicerae samples were determined simultaneously using the developed HPLC-ELSD method. The developed analytical procedure was proved to be a reliable and rapid method for the quality control of Flos Lonicerae.

JPEG2000 is a new compressed standard of static image, Kakadu is a open source system which can be higher efficiency to realize the algorithm of JPEG2000. This article introduces the codec construction and the compressed stream structure in JPEG2000, analyzes the construction of Kakadu and image compression class in Kakadu, and then carries on application experiments based on JPEG2000 in Kakadu 2.2 platform. Experiments show that the compression of interest image region has higher transfer rate and lower memory compared with the original image, and JPEG2000 has higher compression rate and better visual quality compared with JPEG.

Digital correlator play an important role for Photon Correlation Spectorscopy. In this paper, the theory of Photon Correlation Spectorscopy (PCS) and the internal structure of digital correlator are described, and by increasing the number of channels to improve the precision. The digital correlator with 256 channels is implemented by FPGA, effectively raising the real-time and precision.

In the general light scattering particle size measurement methods, the inversion error of results is nonuniform distribution. To solve this problem, genetic algorithms based on real number coding were proposed to be applied in the inversion of particle size distribution. In this method, the fitness function was further improved in order to reduce the individual error, it not only considered sum of all errors but also took into account the individual maximum error. With this improved fitness function, the error distribution is homogenized. The light spectrum about measurement and calculation are basic entirely fitting. The results show that the algorithm is accurate and reliable.

Two for the price of one: A new tandem reaction involving two consecutive, competitive nucleophilic additions was developed to construct a series of densely functionalized propargylic alcohol derivatives from simple materials without functional protection, in which a variety of electrophiles including cyclopropanone and aromatic aldehydes have been successfully employed. Multiple functionalities in products 1and 2make them versatile structural motifs for further elaboration.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.