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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, N2physisorption, 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.

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, N2adsorption–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.

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–TiO2catalysts were investigated using various characterization technologies including FTIR, XRD, SEM, TEM, N2-physisorption, and NH3-TPD. Further, we investigated the use of PW–TiO2composites as heterogeneous acid catalysts for the catalytic esterification of oleic acid. Among all series of catalysts, the calcined PW–TiO2at 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%.

ABSTRACTNonalcoholic fatty liver disease (NAFLD) has become a major public health issue as its progression increases risks of multisystem morbidity and mortality. Recent evidence indicates a more complex relationship between hypertension and NAFLD than previously thought. In this study, a comprehensive literature search was used to gather information supporting the comorbidity phenomenon of hypertension and NAFLD. Then, systems biology approach was applied to identify the potential genes and mechanisms simultaneously associated with hypertension and NAFLD. With the help of protein-protein interaction network-based algorithm, we found that the distance between hypertension and NAFLD was much less than random ones. Sixty-four shared genes of hypertension and NAFLD modules were identified as core genes. Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analysis indicated that some inflammatory, metabolic and endocrine signals were related to the potential biological functions of core genes. More importantly, drugs used to treat cardiovascular diseases, hypertension, hyperlipidemia, inflammatory diseases and depression could be potential therapeutics against hypertension-NAFLD co-occurrence. After analyzing public OMICs data, ALDH1A1 was identified as a potential therapeutic target, without being affected by reverse causality. These findings give a clue for the potential mechanisms of comorbidity of hypertension and NAFLD and highlight the multiple target-therapeutic strategy of NAFLD for future clinical research.

Numerous studies focused on the human exposure to plasticizers via dermal contact; however, the percutaneous penetration of plasticizers was seldom considered in exposure assessment. In the present study, skin wipes of palms, back-of-hands, and forehead were collected from 114 participants (ages: 18–27). There was no significant difference between the levels of phthalates from palms and back-of-hand, while all phthalates collected from the forehead were significantly higher than those from palms and back-of-hand (p< 0.001); di(2-ethylhexyl)phthalate levels were substantially higher than other detected phthalates followed by di(n-butyl)phthalate and di(isobutyl)phthalate (DiBP), and for alternative plasticizers, bis-2-ethylhexyl terephthalate levels were substantially higher than acetyltributyl citrate and bis-2-ethylhexyladipate. Skin permeation and metabolism of phthalates was assessed using human skin equivalent models. The permeability coefficient (kp) values of phthalates were significantly negatively correlated with their log octanol–water partition coefficient (log Kow), while a significantly positive correlation was found between the log Kowand the cumulative amounts of phthalates in the cells. The proportion of phthalate intake via dermal exposure to skin wipes ranges from 1.3% (for dimethyl phthalate) to 8.6% (for DiBP) and suggests that dermal absorption is a significant route for adult phthalate exposure.

Biofuel synthesis is of great significance for producing alternative fuels. Among the developed catalytic materials, the metal-organic framework-based hybrids used as acidic, basic, or supported catalysts play major roles in the biodiesel production. This paper presents a timely and comprehensive review of recent developments on the design and preparation of metal-organic frameworks-based catalysts used for biodiesel synthesis from various oil feedstocks, including MILs-based catalysts, ZIFs-based catalysts, UiO-based catalysts, Cu-BTC-based catalysts, and MOFs-derived porous catalysts. Due to their unique and flexible structures, excellent thermal and hydrothermal stability, and tunable host-guest interactions, as compared with other heterogeneous catalysts, metal-organic framework-based catalysts have good opportunities for application in the production of biodiesel at industrial scale.

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, N2adsorption-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.

How to achieve transmissions in an energy-efficient way in multi-hop decode and forward (DF) relay cognitive radio sensor networks (CRSNs) is important since sensor nodes in CRSNs are usually battery powered. This paper aims to maximize energy efficiency (EE) by joint optimizing sensing time and power allocation in multi-channels & multi-hops DF relay CRSNs under constraints on outage probability and sensing performance. First, we design a channel selection scheme for sensing according to the available probabilities of multi channels. Second, we analyze the expected throughput and energy consumption and formulate the EE problem as a concave/ concave fractional program. Third, coordinate ascent and Charnes-Cooper Transformation (CCT) methods are used to transform the nonlinear fractional problem into an equivalent concave problem. Subsequently, the closed form of outage probability is derived and the convergence rate of the iterative algorithm is analyzed. Finally, simulation results show that the proposed scheme can achieve effective EE.

Two types of ordered mesoporous ZSM-5 zeolites with different mesopores were synthesized by a two-step method. First, carbonaceous SBA-15 was produced by in situcarbonization of SBA-15/P123 composite. Then the obtained SBA-15/C composite was transformed into crystallized mesoporous ZSM-5 by impregnation TPAOH followed by steam-assisted crystallization. The final calcined samples synthesized with typical SBA-15/P123 precursor showed a wormlike morphology with the mean mesopore size of 4.6 nm, while samples synthesized with the addition of trimethylbenzene as swelling agent in the precursor exhibited the morphology of microsphere with the mesopore size of about 9.5 nm. Both two types of mesoporous ZSM-5 zeolites exhibited large surface area and mesopore structure. The steam-assisted crystallization (SAC) was performed with lower consumption of solvents. This two-step method may also be suitable for synthesizing other ordered mesoporous zeolites used as catalysts in some catalytic processes.

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, N2physisorption, UV-vis diffuse reflection spectroscopy, and X-ray photoelectron spectroscopy techniques were used to characterize the as-obtained composites. Intriguingly, C-STA@ZrO2exhibits 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@ZrO2was also investigated. This work may provide a new and significant guideline for exploring excellent performance of MOF-derived hybrid material for wastewater purification.

As an industrial byproduct, autoclaved aerated concrete waste (AACW) was used as an efficient and economic adsorbent for Cd (II) removal in wastewater. The structure and physical properties of AACW were characterized by XRF, SEM, XRD and its adsorption properties for removal of 3 mg/L Cd (II) under different conditions were also investigated. The results showed that the removal rate of AACW for Cd (II) has attained 97% after 90 min when the initial dosage of AACW was 10 g/L. The adsorption process was fitted to Langmuir model and pseudo-second-order kinetic model. Physisorption and chemisorption were both observed during the process. Besides, AACW possesses comprehensive removal effects for other heavy metal ions in industrial wastewater. The adsorption of Cd (II) ion was affected by other metal ions and different ions in the solution showed different inhibitory effects. Taken together, the AACW recycled from the construction process could serve as a promising adsorbent for toxic metals remediation from aqueous solution.

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, N2physisorption, 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.

Experimental results show that the CrowdDesigner outperforms several strong personalized product description generation methods in personal interest coverage, language organization and detailed product information. In addition, the personalized product descriptions generated from the Crowd-Designer can be used as product recommendation texts on the E-commerce web pages, product recommendation pages in mobile apps, offline electronic advertising screens and so on.

In 5G, the unmanned aerial vehicle (UAV) is regarded as an essential way to support energy-saving, reliable, and low-cost data collection in wireless sensor networks. However, UAV-based data collection inevitably suffers from more significant data collection delays due to the UAV movement time in large application scenarios. In this paper, we consider a UAV-enabled wireless sensor network under the uncorrelated Rician fading channel, where a multi-antenna UAV is dispatched to collect data from ground sensor nodes (SNs). The objective is to minimize the mission completion time, including UAV flight and data collection time, by jointly optimizing UAV trajectory, UAV-SN transmission scheduling, and trajectory-based time allocation under the constraints of UAV speed, outage probability, data size, and transmission power. To solve this nonconvex problem, we decompose it into two subproblems: 1) trajectory optimization and 2) UAV-SN transmission scheduling and trajectory-based time allocation optimization. In the trajectory optimization, we first rewrite the outage probability constraint into the communication distance constraint and propose a Spiral-based method to find the shortest trajectory covering all SNs. Then, we propose a scheduling initialization algorithm and employ alternating optimization to solve the UAV-SN transmission scheduling and trajectory-based time allocation optimization. Finally, numerical results show that the proposed algorithm outperforms the benchmark and typical algorithms in terms of the mission completion time through a large number of experiments.

In this study, crashed autoclaved aerated concrete (CAAC) was recycled as a solid waste for the removal of low concentration of phosphate (1 mg/L). The effects of dissolved calcium (Ca2+) and pH on phosphate removal were investigated. The materials including calcium chloride (CaCl2) and calcium carbonate (CaCO3) were selected to investigate the removal mechanism of low concentration of phosphate by CAAC. X-ray fluorescence, X-ray diffraction patterns, FT-IR, SEM, and EDS analyses were used to characterize the surface shape, contained elements, and internal structure of CAAC. Results showed that the removal rate of phosphate was increased according to the increase in pH. The CAAC showed poor effect on phosphate removal at acidic condition, but had great removal efficiency in the pH range of 10–12 due to the formation of hydroxyapatite (HAP, Ca5(OH)(PO4)3) corresponding to characterization. Dissolved calcium and insoluble calcium compounds in CAAC can combine with the phosphate and hydroxyl groups to form HAP in alkaline condition and subsequently remove the phosphate. SEM images exhibited the surface of CAAC including some pieces of irregular crystal. After phosphate removal, its surface was covered with a layer of agglomerations confirmed to be HAP according to characterization. To avoid adjusting the pH of solution to strong alkalinity, CAAC was modified by sodium hydroxide solution (NaOH) to increase its activity. Modified products showed a high efficiency for phosphate removal (98.67%). Collectively, the present results demonstrated that the employment of crystallization using CAAC could be a promising technology for the advanced treatment of phosphate from low concentration in municipal secondary effluent.

Glycerol, a major co-product in the process of biodiesel production, is a promising precursor to a variety of high value fine chemicals such as glyceric acid, dihydroxyacetone, lactic acid and tartronic acid via the corresponding chemoselective oxidation reactions. One of the prospective routes to selectively oxidize glycerol and yield products with good selectivity is the use of nano-sized metal particles as heterogeneous catalysts. In this short review, recent developments in chemoselective oxidation of glycerol to specific products over nano-sized metal catalysts are described. Attention is drawn to various reaction parameters such as the type of the support, the size of the metal particles, and the acid/base properties of the reaction medium which were illustrated to largely influence the activity of the nanocatalyst and selectivity to the target product.

Cellulose considered as one of the most abundant renewable resources have great potential for the production of bio-fuels and chemical building blocks bearing a diverse range of applications. Among various approaches for the efficient transformation of cellulose, nanoparticles on ordered porous materials with high surface area and unique particle morphology employed as heterogeneous catalysts exhibit dramatic improvement of catalytic activity and selectivity. In this review, selective conversion of cellulose as well as cellobiose through different types of reactions including hydrolysis, isomerization, dehydration, hydrogenation/hydrogenolysis, oxidation, hydrogenation-dehydration, and gasification/pyrolysis promoted by mono- or bi-functional nanocatalysts has been described. Emphasis is also paid to discuss plausible reaction pathways catalyzed by functionalized nanoparticles in these catalytic processes.

Biomass derived carbohydrates and related raw materials are the most abundant renewable resources available which have great potential as bio-fuels and chemical building blocks for a diverse range of applications. They can reduce to a large extent our over dependence on fossil-fuel resources. Over the past decade, various acid and/or base catalysts have been used to transform biomass resources into different kinds of furans, providing a feasible way for sustainable energy supply and chemicals. Compared to homogeneous catalytic systems, transformations mediated by heterogeneous catalysts are often associated with distinct advantages such as easy separation, reusability, lower catalyst loading, anti-corrosion effects and simple operation for continuous conversion. In this review, the direct transformation of biomass into furans with the help of heterogeneous catalysts is discussed. The effects of reaction conditions on the intrinsic reactivity and selectivity of each catalytic system are assessed; special emphasis has been paid to comprehend the mechanism for the synthesis of furan-based compounds from biomass resources using heterogeneous catalysts.

ZrMo mixed oxides modified by a series of low-cost monofunctional carboxylic acids including stearic acid, palmitic acid, myristic acid, and lauric acid were prepared and were characterized using TG analysis, XRD, FT-IR, NH3-TPD, and SEM techniques. These strong solid acids were evaluated as heterogeneous catalysts with porous property for the conversion of carbohydrates to 5-hydroxymethylfurfural (HMF) by oil heating rather than using microwave heating, in the aim of facilitating the industrial feasibility of this catalytic process and discussing the relation between surface acidity and reactivity in carbohydrates to HMF conversion. Under the optimal reaction conditions, moderate yields of HMF could be achieved from fructose, glucose, sucrose, and cellulose, and the strong solid catalysts can be recycled for seven times with no significant loss of activity.

The tendency in recent decades is to develop environmentally friendly heterogeneous catalytic systems for organic transformations. In particular, chemical reactions cooperatively promoted by solid acid-base bifunctional catalysts with good dispersion of active sites and high catalytic performances have aroused much attention. In this review, recent advances in preparation and application of solid acid-base bifunctional catalysts for organic transformations are described, and special emphasis is paid to understand the catalytic mechanisms of the acid-base bifunctionality. Furthermore, strategies for well positioning acidic sites and basic sites to cohabitation and cooperation are briefly discussed.

In order to investigate the effect of the substitution groups on the intercalation, nine quaternized carboxymethyl chitosans (QCMCs) with different degree of substitution (DS) of carboxymethyl and quaternary ammonium groups were intercalated into the interlayer of organic montmorillonite (OMMT). Small-angle XRD, TEM and FT-IR techniques were used to characterize the structure and morphology of QCMC/OMMT nanocomposites, the thermogravity analysis (TGA) was performed to evaluate the thermal stability. The results revealed that positively charged quaternary ammonium groups contributed to the intercalation of QCMC, certain amount of negatively charged carboxymethyl groups could also induce better intercalation, but too much carboxymethyl groups prevented the entrance of QCMC into the interlayer of OMMT. In addition, as carboxymethyl and quaternary ammonium groups increased, the interaction between QCMC and OMMT was stronger, but the thermal stability was lower. When DS of carboxymethyl groups and quaternary ammonium groups in QCMC were respectively 53 and 41 , the exfoliated nanocomposite was obtained, in this case, its thermal stability was the highest.

An ideal periosteum substitute should be able to mimic the periosteum microenvironment that continuously provides growth factors, recruits osteoblasts, and subsequent extracellular matrix (ECM) mineralization to accelerate bone regeneration. Here, a calcium‐binding peptide‐loaded poly(ε‐caprolactone) (PCL) electrospun membrane modified by the shish‐kebab structure that can mimic the periosteum microenvironment was developed as a bionic periosteum. The calcium‐binding peptide formed by the negatively charged heptaglutamate domain (E7) in the E7‐BMP‐2 with calcium ion in the tricalcium phosphate sol (TCP sol) through electrostatic chelation not only extended the release cycle of E7‐BMP‐2 but also promoted the biomineralization of the bionic periosteum. Cell experiments showed that the bionic periosteum could significantly improve the osteogenic differentiation of the rat‐bone marrow‐derived mesenchymal stem cells (rBMSCs) through both chemical composition and physical structure. The in vivo evaluation of the bionic periosteum confirmed the inherent osteogenesis of this periosteum microenvironment, which could promote the regeneration of vascularized bone tissue. Therefore, the hierarchical nanostructured electrospun membrane with periosteum‐mimic microenvironment is a promising periosteum substitute for the treatment of bone defects. In this study, a hierarchical nanostructured electrospun membrane with a periosteum‐mimic microenvironment is successfully constructed by a two‐step method. As a periosteum substitute, it can continuously provide growth factors, recruit osteoblasts, and subsequently promote extracellular matrix mineralization, and shows great clinical advantage in the treatment of critical‐size bone defects with periosteum damage.

Bone Regeneration In article number 2101195, Chaojing Li, Fujun Wang, Zhimou Yang, Lu Wang, and co‐workers construct a hierarchical nanostructured electrospun membrane with a periosteum‐mimic microenvironment. As a periosteum functional substitute covering the surface of bone defects, it can continuously provide growth factors, recruit osteoblasts, causing subsequent extracellular matrix mineralization, and exhibits excellent vascularized bone regeneration effects in vivo.

The impregnation of phosphotungstic acid (HPW) with porous cobalt-cerium oxide (HPW@CoCeO) has been prepared by pyrolysis of CoCe-MOF and used for the production of methyl oleate from oleic acid and methanol. FTIR, XRD, SEM, TEM, N2 adsorption/desorption, and NH3-TPD were characterized for the prepared composites. Simultaneously, the effects of reaction time, substrate molar ratio, temperature, and catalyst loading on catalytic activity were highlighted, and the conversion of 67.2% was reached after 4 h at 60°C. Importantly, HPW@CoCeO was reusabe and reused more than eight times, and the oleic acid conversion could be maintained at 61.8% without significant activity loss. Thus, the HPW@CoCeO composite could be used as acid catalysts for sustainable energy production.

Methylmercury (MeHg) has remarkable toxicological effects on humans, plants, and other lives in the environment, which may restrict the comprehensive utilization of biomass source in view of possibly forming biohazardous waste. In this study, a kinetic study of MeHg degradation under UVB, UVA, natural light, and dark was carried out. The result showed that light radiation enhanced MeHg degradation but had no significant influence on the final balance between MeHg and inorganic mercury (Hg2+) in pure water. The balance is of great importance and can be used as a key fundamental to estimate MeHg cycling in other complicated aquatic environments. MeHg degradation was identified to be second-order reaction using the fitting optimization level of the regression equation, and the second-order rate constants were 1.61, 0.82, and 0.91 L·ng−1·d−1, half-lives were calculated to be 0.62, 1.3, and 1.08 d for UVB, UVA, and natural light, respectively. A possible MeHg degradation mechanism was proposed, and it could perfectly explain the results obtained in this paper and some previous studies.