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In this article, silicotungstic acid (STA)-loaded metal–organic framework (MOF)-derived composites (C-STA@ZrO2) were successfully synthesized by simple strategies. X-ray diffraction, Fourier transform infrared, scanning electron microscopy, energy-dispersive X-ray, N2 physisorption, UV-vis diffuse reflection spectroscopy, and X-ray photoelectron spectroscopy techniques were used to characterize the as-obtained composites. Intriguingly, C-STA@ZrO2 exhibits excellent photocatalytic performance, and rhodamine B (RhB) (40 mg·L−1) in water can be degraded to 93.9% after 120 min of irradiation. Moreover, various catalysts, catalyst dosage, and dye concentrations on RhB degradation were evaluated. Besides, the reusability of C-STA@ZrO2 was also investigated. This work may provide a new and significant guideline for exploring excellent performance of MOF-derived hybrid material for wastewater purification.

In this article, Bi2O3@Zn-MOF hybrid nanomaterials were synthesized by supporting Zn-based metal–organic framework (Zn-MOF) through the hydrothermal method. X-ray diffractometer, Fourier transform infrared, scanning electron microscopy, energy-dispersive X-ray, N2 physisorption, X-ray photoelectron spectroscopy, and UV-Vis were used to characterize the physical and chemical properties of Bi2O3@Zn-MOF nanomaterials. The photocatalytic activity of the as-prepared hybrid has been studied over the degradation of rhodamine B (RhB). A catalytic activity of 97.2% was achieved using Bi2O3@Zn-MOF nanocomposite with the loading of 0.18 g Bi2O3, after 90 min of exposure to visible light irradiation, and the high photocatalytic performance was mainly associated with the nanorod structures, larger pore size, and broaden visible light absorption region due to the synergistic effect of the constituting materials. Furthermore, the Bi2O3@Zn-MOF nanocomposite can be reused three times and the degradation rate of RhB was maintained at 77.9%. Thus, the Bi2O3@Zn-MOF nanocomposite can act as a potential photocatalyst for the photodegradation of organic dyes in environmental applications.

In this article, Bi-based metal–organic framework-supported silicotungstic acid (STA) was synthesized by a simple hydrothermal method and used as a precursor for the preparation of the Bi-based MOF-derived catalyst (STA@C-Bi-BDC). Using a combination of FTIR, XRD, SEM-EDS, N2 adsorption–desorption, TG, UV-Vis DRS, and XPS techniques, the successful immobilization of STA groups on Bi-MOF-derived C-Bi-BDC was assessed. Furthermore, the photocatalytic performance of the as-prepared catalysts was investigated in the degradation of the RhB dye process under visible light. Within 120 min of visible light exposure, the high degradation rate of RhB (92.7%) by STA@C-Bi-BDC system was achieved, which was a lot larger than the STA (39.4%), C-Bi-BDC (59.2%), and STA@Bi-BDC (74.0%) system, and cyclic experiments exhibit that the STA@C-Bi-BDC is a relatively stable photocatalyst. More importantly, the catalyst shows high applicability for the degradation of other dyes. This study reveals a comprehensive strategy for the design of efficient Bi-based MOF-derived photocatalyst for organic dye-based wastewater treatment.

In the present study, a facile solvothermal method was used for the synthesis of silicotungstic acid (HSiW) immobilized on Ce-based metal organic framework (Ce-BDC) and embedded in Zr-based metal-organic framework (UiO-66(Zr)) composite catalyst, namely, Ce-BDC@HSiW@UiO-66 for the production of biodiesel through green fatty acid esterification. The obtained hybrids were characterized by various characterization technologies, including Fourier transform infrared, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N2 physisorption, X-ray photoelectron spectroscopy, and temperature-programmed desorption of NH3 (NH3-TPD) analysis. The characterization analyses showed that the hybrids have been successfully synthesized. Also, the volume and pore size of UiO-66(Zr) were changed by introducing HSiW@Ce-BDC, and the resulting Ce-BDC@HSiW@UiO-66 possessed the mesoporous structure and relatively high surface area. Simultaneously, the NH3-TPD analysis of Ce-BDC@HSiW@UiO-66 reveals that the acid strength was increased in comparison with HSiW@Ce-BDC. In addition, the composite Ce-BDC@HSiW@UiO-66 demonstrated high catalytic activity, and the oleic acid esterification gave 81.5% conversion at optimum conditions of 0.2 g catalysts, 1:30 oleic acid to methanol molar ratio at 130°C for 4 h. More interestingly, after six recycling cycles, the reduction in the conversion rate was only 4.6%, indicating that Ce-BDC@HSiW@UiO-66 has excellent reusability. Our study provides an effective approach to synthesize multifunctional hybrids for green biofuel production.

For nearly a century, the excessive discharge of organic contaminants has gradually polluted water and endangered people's health, and photocatalysis has been prominently employed to remove persistent recalcitrant organic. Here, MIL‐101(Cr) was firstly employed to introduce thin‐layered Bi2O2CO3 for the formation of Bi2O2CO3/MIL‐101(Cr) nanosheet composite, by a simple and low‐temperature in‐situ growth approach. The phase, morphology, optical, and surface characteristics of the fabricated composite were characterized through XRD, FTIR, SEM‐EDS, N2 adsorption–desorption, UV–Vis DRS, PL, TG, and XPS techniques, and the ability in the photocatalytic breakdown of rhodamine B (RhB) molecule under visible light was also studied. The results of characterization analysis and optical analysis exhibited that Bi2O2CO3/MIL‐101(Cr) has large pore size, good visible light response‐ability, and the heterojunction created by intercalating Bi2O2CO3 on MIL‐101(Cr). Photocatalytic studies revealed that Bi2O2CO3/MIL‐101(Cr) had superior RhB degradation activity than pure MIL‐101(Cr) and Bi2O2CO3, which achieved 97.1% with visible light irradiation for 20 mg/l RhB. Meanwhile, the Bi2O2CO3/MIL‐101(Cr) composite displayed good recyclability after three cycles as revealed by XRD and FTIR analysis proving their excellent stability. This study provides feasible insight into developing novel and efficient MIL‐101‐based heterojunction catalysts for environmental remediation in the future. [ABSTRACT FROM AUTHOR]

This study explores the innovative application of iron filings solid waste, a byproduct from mechanical workshops, as a heterogeneous catalyst in the production of biodiesel from waste cooking oil. Focusing on sustainability and waste valorization, the research presents a dual-benefit approach: addressing the environmental issue of solid waste disposal while contributing to the renewable energy sector. Particle size distribution analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray fluorescence (XRF), Thermal analysis (TG-DTA), and FTIR analysis were used to characterize the iron filings. The response surface methodology (RSM) was used to guide a series of experiments that were conducted to identify the optimum transesterification settings. Important factors that greatly affect the production of biodiesel are identified by the study, including catalyst loading, reaction time, methanol-to-oil ratio, reaction temperature, and stirring rate. The catalyst proved to be successful as evidenced by the 96.4% biodiesel conversion efficiency attained under ideal conditions. The iron filings catalyst's reusability was evaluated, demonstrating its potential for numerous applications without noticeably decreasing activity. This work offers a road towards more environmentally friendly and sustainable chemical processes in energy production by making a strong argument for using industrial solid waste as a catalyst in the biodiesel manufacturing process. [ABSTRACT FROM AUTHOR]

Development of an energy‐efficient and economical route is necessary for society to synthesize green biofuels. Herein, cobalt‐doped tungstophosphoric acid (Co‐HPW) is in‐situ impregnated in the Zr‐based metal–organic framework (MOF‐801) forming composite of Co‐HPW/MOF‐801. The chemical composition, morphology, and acidic sites of the Co‐HPW/MOF‐801 composite were analyzed through x‐ray diffractometer (XRD), Fourier transform infrared (FTIR), scanning electron microscope (SEM), energy‐dispersive x‐ray spectroscopy (EDS), thermogravimetric analysis (TG), N2 physisorption, ammonia temperature‐programmed desorption (NH3‐TPD), pyridine‐adsorbed infrared spectra (Py‐FTIR), and x‐ray photoelectron spectroscopy (XPS). The catalytic performance of the as‐synthesized catalyst was explored to catalyze esterification of lauric acid (LA) with methanol. The outcomes revealed that the Co‐HPW/MOF‐801 nanocatalyst achieved a high conversion of 86.3% under the optimized reaction condition (catalyst amount of 0.15 g, temperature of 100°C, time of 4 h, and methanol/LA molar ratio of 20:1). The excellent catalytical performance is mainly due to the large BET surface area, exposure of more active centers from available pore structure, and simultaneous possession of high Lewis and Brønsted acidity. Furthermore, the kinetic study revealed that the reaction process was kinetically controlled and the activation energy was found to be 42.1 kJ/mol. The results suggest that the synthesized Co‐HPW/MOF‐801 nanocatalyst is an environmental greenness, low cost, and suitable for easy scale‐up for the production of biofuels. [ABSTRACT FROM AUTHOR]

MIL-125(Ti) metal–organic framework-derived nanoporous titanium dioxide–heteropoly acid (PW–TiO2) have been synthesized by a facile hydrothermal approach and subsequent calcination, and the PW–TiO2 catalysts were investigated using various characterization technologies including FTIR, XRD, SEM, TEM, N2-physisorption, and NH3-TPD. Further, we investigated the use of PW–TiO2 composites as heterogeneous acid catalysts for the catalytic esterification of oleic acid. Among all series of catalysts, the calcined PW–TiO2 at a temperature of 350°C showed excellent activity with a high conversion of 90.5% at 160°C for 4 h. More importantly, the catalyst could be simply separated via centrifugation and reused for six cycles and shows a relatively high conversion of 74.8%.

With the rapid development of the E-commerce, the text of the products?? advertisement and recommendation is extremely vital in the case that people cannot touch the real products. Traditional product descriptions which are written manually show the same product information to all users, which do not consider that different users pay attention to different attributes. Moreover, the efficiency of manually written product descriptions cannot match the growth rate of products, so how to automatically generate personalized product descriptions has become a frontier research problem. This paper mainly studies the generation of personalized product description, takes the personalized characteristics of users into account and generates the product description text corresponding to the interest for each user. Due to the lack of personalized product description data set, the CrowdDepict model is proposed. It collects relevant corpus through public data sources such as Douban and JD, and generates personalized product description with product comments, etc. The experimental results show that the personalized product description model CrowdDepict can automatically generate the personalized product description according to the user preference, the description covers the user interest and product characteristics, and the text expression is smooth.

Nickel salts of Keggin-type heteropolyacid on Zr(IV)-based metal-organic frameworks (UiO-66) has been synthesized via ion-exchange followed by a facile one-pot hydrothermal method. The synthesized catalysts underwent FT-IR, N2 adsorption-desorption, powder XRD, SEM and TEM analysis. The NiHSiW/UiO-66 catalyst was used as a new and effective solid acid in the catalytic transfer free fatty acid to biodiesel with an optimum conversion of 86.7%. The excellent activity of the NiHSiW/UiO-66 nanocatalyst was closely related to its high specific surface area, nano-sized catalyst, and the synergistic effects of NiHSiW salts and UiO-66 matrix. Importantly, a relatively stable catalytic performance was achieved for 8 repeated cycles. Finally, kinetics of the esterification reaction have been assumed to be of pseudo first order.

In order to meet the high-speed, parallel and high-precision data acquisition of the multi-point sensitive pressure sensor signals on the surface of the rotor blade, and with the functions of program-controlled gain amplification and anti-aliasing filtering, a portable multi-channel high precision front-end acquisition system with FPGA as the core control unit is designed. The measured signals are processed by signal conditioning and filtering module to improve the quality, and then collected by ADC sampling module, and finally the acquired data are transmitted to the main control board for analysis and processing through SPI bus in real time，achieving synchronous and high-precision acquisition of multi-channel signals. The test results show that the system has stable performance, in small signal acquisition under large interference environment, the amplitude accuracy can attain 0.1%, the spurious-free dynamic range can reach up 60 dBc. The system utilizes a portable design, small size, low cost, strong scalability, and has a good application value.

This study presents a novel method for synthesizing 1,4-disubstituted 1,2,3-triazole derivatives through a one-pot, multi-component addition reaction using flower-like Cu2O microbeads as a catalyst. The flower-like Cu2O microbeads were synthesized using an aqueous extract of Artimisia Campestris L. This extract demonstrated the capability to reduce and stabilize Cu2O particles during their initial formation, resulting in the formation of a porous flower-like morphology. These Cu2O microbeads exhibit distinctive features, including a cubic close-packed (ccp) crystal structure with an average crystallite size of 22.8 nm, bandgap energy of 2.7 eV and a particle size of 6 μm. Their catalytic activity in synthesizing 1,4-disubstituted 1,2,3-triazole derivatives was investigated through systematic exploration of key parameters such as catalyst quantity (1, 5,10,15, 20, and 30 mg/mL), solvent type (dimethylformamide/H2O, ethanol/H2O, dichloromethane/H2O, chloroform, acetone, and dimethyl sulfoxide), and catalyst reusability (four cycles). The Cu2O microbeads significantly increased the product yield from 20% to 85.3%. The green synthesis and outstanding catalytic attributes make these flower-like Cu2O microbeads promising, efficient, and recyclable catalysts for sustainable and effective chemical transformations. [ABSTRACT FROM AUTHOR]

In order to ensure the reliability of long-distance control and data transmission in data acquisition applications, and meet the requirements of multi-channel signal interface switching and parallel data acquisition, a multi-channel acquisition and switching system based on FPGA and TCP/IP is designed. The system uses Xilinx Spartan-6 series FPGA as the main control chip, which can meet the switching of 8 groups of 13 channels, and the synchronous acquisition and real-time transmission of 16 analog signals. The system uses the architecture of FPGA+TOE to realize TCP/IP , and is equipped with a monitoring host computer. The experimental results show that the system is capable of long-term stable multi-channel switching , high-speed acquisition and real-time transmission. It is convenient to use and highly reliable, and has certain application value in the field of distributed acquisition.

In order to meet the strict requirements of precision, real-time and synchronization of data acquisition in the process of precision equipment monitoring, a multi-channel, real-time and high-speed data acquisition system based on FPGA is designed. This system uses the Spartan6 series FPGA of Xilinx as the core control device, which realizes functions such as data acquisition control, data buffering, data processing, data storage, data transmission and synchronous clock control. The test shows that the scheme has the advantages of high precision, fast speed, good reliability, strong real-time performance and low cost.