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To overcome the low energy density and poor conductivity of conventional electrode materials for building supercapacitor, herein, a hybrid hydrogel prepared from compositing bio-based chitosan with holey graphene oxide by microwave-assisted hydrothermal is proposed. This binary hydrogel is endowed with heteroatomic functional groups and conductive porous network by chemical pretreatments, where amides and carboxyl groups are introduced during the acylation modification of chitosan to enable it soluble in water for sufficient reaction, while the oxidation etching for graphene oxide in the defect area by H

Waste oil, like waste cooking and acidic oil, are two promising carboxylic acids feedstocks that can be converted into hydrocarbons by the pyrolytic method, usually through DCO2 and DCO processes. DFT is employed to investigate the deoxygenation mechanism using octanoic acid as a model compound in this work. Additionally, pyrolysis of the above samples was carried out at atmospheric pressure, temperature below 773.15K. GC-MS, GC and TG-FTIR-MS test measures were used to analyze pyrolytic products. The DFT results reveal that pyrolysis conversion of waste oil was a direct and effective deoxygenation method. And high alkene content endowing pyrolytic oil greatly potential to upgrade for high-quality biofuel production. Finally, pyrolytic oil was upgraded by SAPO-11-Pd/C can increase the components of iso-hydrocarbons, further can faction cut to obtain three biofuel fractions. Fraction blending with fuels could decrease the cold filter plugging point of final fuels, dramatically improving the commercial value of pyrolytic oil and effectively solving the waste oil disposal problem.

A highly stable Pd-loaded N-doped carbon catalyst (ACNpd) for phenol hydrogenation was prepared from chitosan by hydrothermal carbonization. ACNpd does not require a reduction step before catalytic use due to the Pd in the as-prepared catalyst mainly exists in the form of Pd0 (80%). The carbon support involves N-containing groups such as pyridinic nitrogen and pyrrolic nitrogen, which could provide basic sites to adsorb phenol effectively. The as-fabricated ACNpd shows high catalytic performance with turnover frequency (TOF) of 29.34 h−1. Accordingly, a phenol conversion of 100% and a cyclohexanone selectivity of 99.1% are achieved in 5 h at 100 °C and 1 MPa H2. This outstanding performance is attributed to the synergetic effects of the Pd particles, the N-functional groups, and the Lewis acid sites on the support. The carbon support presents intrinsic Lewis acid sites due to its electrophilicity, and Pd doping further increases the strength of such acid sites as it causes electron-deficient structural features. Moreover, the Lewis acid sites inhibit the over-hydrogenation from cyclohexanone to cyclohexanol. This study provides new insights into the application of functional biomass-based carbon materials as catalyst supports.

Carbon aerogels are prepared by a thermal treating-freeze drying approach from chitosan, with glycine hydrochloride ionic liquid (IL) acting as solvent and nitrogen source. Different post-treatments such as ball milling and high temperature carbonization are employed to functionalize the obtained carbon aerogels with tuned properties, making it promising candidates as fluorescence material (NACs-Q), electrode material (FDC-800) and catalyst support (NACPd-C). NACs-Q is water-soluble quantum dot with average particle sizes of 3.8 nm, presenting excitation-/emission-independent and pH-sensitive properties, which could be used as sensor for testing acetone vapor or an “on-off-on” sensor for detections of Fe3+ and vitamin C in fruits. FDC-800 exhibits fluffy lamellar structure with developed micro-mesopores and nitrogen-containing groups on their surfaces, which is beneficial for building flexible solid-state supercapacitor with excellent performance, delivering a capacitance of 208F/g at 0.5 A/g, and achieving an energy density of 7.2 W h/kg at a power density of 50 W/kg. Moreover, NACPd-C can be used as catalyst for phenol hydrogenation, and phenol conversion of 100% with cyclohexanone selectivity of 98.3% is achieved, due to the synergetic effects of the Pd active-site, the N-containing groups, and the Lewis acid sites on the support.

Lignin-rich black liquor produced from paper-making industries causes severe eco-issues, and how to make full use of it to gain an environmental and economic balance has been gaining increasing attention.

Cyclohexanone is widely used in coatings, pesticides, dyes, lubricants, and other industries due to its high solubility and low volatility, but designing highly active and stable heterogeneous cata...

An environmentally benign cascade redox process was developed for the efficient construction of the pharmaceutically significant spirocyclic tetrahydroquinolines via sequential SNAr/Knoevenagel condensation/[1,5]-hydride transfer/cyclization. This green transformation has the features of being catalyst-free, additive-free, operationally simple, and has high step- and atom-economy.

Background As one of the most important modified products of rosin, rosin glyceride was widely used in many aspects. However, the preparation of rosin glyceride is always unfriendly due to the use of liquid catalyst, such as H2SO4 and H3PO4. Methods The rosin glyceride with low acid value was synthesized in vacuum conditions using a novel Lewis acidic ionic liquid 1–butyl–3–methylimidazolium chloroscandinate[BuMeim][Sc2Cl7] as catalyst. The [BuMeim][Sc2Cl7] is of excellent catalytic activity and stability. The efficient catalytic activity was studied via the combined Density Functional Theory (DFT) and experimental conditions. Significant findings The DFT proved the free energy of the esterification could reach to 31.6 Kcal/mol, which illuminates that the excellent coordination of the anions and cations in the [BuMeim][Sc2Cl7] greatly reduces the reaction energy barrier and promotes the efficient progress of the reaction. As a result, [BuMeim][Sc2Cl7] is a good catalyst for the esterification of rosin and glycerol to prepare rosin glyceride. Furthermore, [BuMeim][Sc2Cl7] could be a potential catalysts for the other esterification.

Polyaluminum chloride modified clay (PAC-MC) is a safe and efficient red tide control agent that has been studied and applied worldwide. Although it is well known that the distribution of hydrolytic aluminum species in PAC affects its flocculation, little is known about the influence of particulars aluminum species on the microalgae removal efficiency of PAC-MC; this lack of knowledge creates a bottleneck in the development of more efficient MCs based on aluminum salts. The ferron method was used in this study to quantitatively analyze the distributions of and variations in different hydrolytic aluminum species during the process of microalgae removal by PAC-MC. The results showed that Ala, which made up 5%–20% of the total aluminum, and Alp, which made up 15%–55% of the total aluminum, significantly affected microalgae removal, with Pearson's correlation coefficients of 0.83 and 0.89, respectively. Most of the aluminum in the PAC-MC sank rapidly into the sediments, but the rate and velocity of settlement were affected by the dose of modified clay. The optimal dose of PAC-MC for precipitating microalgae was determined based on its aluminum profile. These results provide guidance for the precise application of PAC-MC in the control of harmful algal blooms.

Porous carbon materials was synthesized using MCM-41as template and self–N–doped porous carbon material was fabricated via a well–directed synthesized 1–butyl–3–methylimidazolium triazole [Bmim]tr, an exemplary ionic liquid (IL) possessing 36.4 wt % N content and dual–aromatic anion/cation. The obtained materials had well–distributed hierarchical meso–/micro–pore structure, a large surface area (1425.6 m2 g−1), and high N content (11.29 wt%), which provided efficient electron transmission capability, thus significantly enhancing the electrochemical performance. At 1.0 A g−1, the specific capacitance from the CN900 sample achieved 376.4 F g−1. In addition, a high energy density of 13.07 Wh kg–1 at 500 W kg–1 was demonstrated. Furthermore, a high stability of more than 97.7% after 10,000 cycles was obtained. This study presents that the dual–aromatic cation/anion–based ILs with high N–content/MCM–41 template strategy is promising for the preparation of self–N–doped carbon materials for supercapacitor applications.

BackgroundOveruse and misuse of antibiotics are major factors in the development of antibiotic resistance in primary care institutions of rural China. In this study, the effectiveness of an artificial intelligence (AI)-based, automatic, and confidential antibiotic feedback intervention was evaluated to determine whether it could reduce antibiotic prescribing rates and avoid inappropriate prescribing behaviors by physicians.MethodsA randomized, cross-over, cluster-controlled trial was conducted in 77 primary care institutions of Guizhou Province, China. All institutions were randomly divided into two groups and given either a 3-month intervention followed by a 3-month period without any intervention or vice versa. The intervention consisted of 3 feedback measures: a real-time warning pop-up message of inappropriate antibiotic prescriptions on the prescribing physician’s computer screen, a 10-day antibiotic prescription feedback, and distribution of educational brochures. The primary and secondary outcomes are the 10-day antibiotic prescription rate and 10-day inappropriate antibiotic prescription rate.ResultsThere were 37 primary care institutions with 160 physicians in group 1 (intervention followed by control) and 40 primary care institutions with 168 physicians in group 2 (control followed by intervention). There were no significant differences in antibiotic prescription rates (32.1% vs 35.6%) and inappropriate antibiotic prescription rates (69.1% vs 72.0%) between the two groups at baseline (p = 0.085, p = 0.072). After 3 months (cross-over point), antibiotic prescription rates and inappropriate antibiotic prescription rates decreased significantly faster in group 1 (11.9% vs 12.3%, p < 0.001) compared to group 2 (4.5% vs 3.1%, p < 0.001). At the end point, the decreases in antibiotic prescription rates were significantly lower in group 1 compared to group 2 (2.6% vs 11.7%, p < 0.001). During the same period, the inappropriate antibiotic prescription rates decreased in group 2 (15.9%, p < 0.001) while the rates increased in group 1 (7.3%, p < 0.001). The characteristics of physicians did not significantly affect the rate of antibiotic or inappropriate antibiotic prescription rates.ConclusionThe conclusion is that artificial intelligence based real-time pop-up of prescription inappropriate warning, the 10-day prescription information feedback intervention, and the distribution of educational brochures can effectively reduce the rate of antibiotic prescription and inappropriate rate.Trial registrationISRCTN, ID: ISRCTN13817256. Registered on 11 January 2020

Levulinic acid (LA) is considered as an important intermediate for production of chemicals, resins, polymers, and fuel additives. Herein, five Bronsted–Lewis acidic ionic liquids (ILs) were synthesized and their acidities of ILs were characterized using FT-IR spectroscopy. The order of their acidic strength was similar to that of the used metal chlorides (ZnCl2 > FeCl3 > CuCl > CrCl3). Cellulose was effectively converted to LA in pure water at 180 °C in 10 h without additives, and the maximum yield of LA was more than 49% over the Bronsted–Lewis IL [HO3S-(CH2)3-py]Cl-FeCl3. The synergistic catalytic effect of the Lewis and Bronsted acidic centers of the catalyst played a significant role for the conversion of cellulose to LA. Some solid residues were formed along with the synthesis of LA, and the result of its characterization suggested that they had good thermal stability and their structures were benzene or amorphous (partially hydrogenated) fused benzene ring. Otherwise, the IL reusability was good, and when it was reused for five times, its catalytic performance was not changed. Therefore, the conversion route for cellulose to LA in pure water with the Bronsted–Lewis acidic ILs provides an environmentally friendly method for biobased-platform from biomass.

Drug-delivery technology is an effective way to promote drug absorption and efficacy. Mesoporous hollow silica material and small-molecule drug ibuprofen were used as a carrier model and as model drug, respectively. By quantum chemical calculation (density functional theory and frontier orbital theory), it was found that the content of geminal silanols on the material surface played a decisive role in the release of the different drugs. The rough hollow materials are easily adsorbed and have a large loading capacity, and so we fabricated a mesoporous hollow silica material (R-nCHMSNs) with a rough surface and rich geminal silanols by using hydroxyl-rich nanocellulose as a template. The content and types of hydroxyl groups on the material surface were studied by 29Si NMR. The loading and delivery of ibuprofen and lysozyme were studied in detail. Materials with rich geminal silanols exhibited excellent delivery properties for different drugs, which shows great potential and research value for drug delivery.

Background The problem of inappropriate use of antibiotics in children is common in many countries. The purpose of the study was to explore patterns of antibiotic prescribing in children’s outpatient clinics in primary care institutions. Methods We obtained prescription data from 75 primary care institutions in Guizhou province recorded by the hospital information system in 2020. The classification of incorrect spectrum of antibiotics, unnecessary use and combined use of antibiotics was based on the Guiding Principle of Clinical Use of Antibiotics (2015, China) and guidelines from the USA Centers for Disease Control and Prevention. Potential risk factors for inappropriate use of antibiotics were identified using a bivariate cross table. The generalized estimation equation was used to identify independent predictors controlling irrational use of antibiotics. Results A total of 158,267 antibiotic prescriptions were retrieved. Acute upper respiratory tract infections were the most common diseases, accounting for 74.9% of all prescriptions. The main antibiotic group used was penicillins (63.7%), followed by cephalosporins (18.8%). Of 137,284 visits, 30.2% of antibiotic prescriptions were appropriate and the percentage of unnecessary use, incorrect spectrum of antibiotics and combined use of antibiotics was 63.8%, 3.6% and 2.4%, respectively. Physicians with lower professional titles and more than 40 years of work duration were relatively more likely to prescribe inappropriate antibiotics. Conclusion The inappropriate use of antibiotics in children is still prominent in primary care institutions of China. The education and training of physicians and caregivers in these institutions should be strengthened.

The preparation of small molecule compounds with a high value from biomass has always been the focus of research, and catalysts with high activity and stability are an essential part of biomass con...

A green and facile synthesis of anisotropic 3D architecture high-performance carbon catalyst has been a hot research topic. Herein, a facile and scalable strategy was developed to fabricate an N, S co-doped microcellular carbon from natural polymers of chitosan (N-source) and lignosulfonate (S-source), with the properties enhanced as a result of pre-cryocrushing of natural polymer-based carbon precursors. The as-prepared 3D architecture carbon is mechanically strong and contains cross-linked hierarchical porous micro-sheets and micro-channels. This N and S co-doped carbon, prepared from pre-cryocrushing of chitosan (60%) and lignosulfonate (40%) precursor (NSC/CC-C/L (60/40)), annealed at 900 °C shows unique structures, with significant defects, rough edges, rich micro/meso-pores, large surface area, N and S doping, and high pyridinic-N and thiophene-S contents. The NSC/CC-C/L (60/40)-900 sample exhibits superior performance with favorable kinetics, methanol resistance, and excellent durability as an ORR catalyst, all of which are much better than a commercial Pt/C and most reported metal-free catalysts. Impressively, the onset potential of the NSC/CC-C/L-900 sample reaches 1.08 V (vs. reversible hydrogen electrode) and the half-wave potential is 0.98 V, which are compared to 1.02 and 0.92 V for Pt/C.

A series of carboxylic acid-functionalized deep eutectic solvents(DES) wereconstructed by a natural organic dicarboxylic acid, oxalic acid (OA), as the hydrogen bond donor and the polyethylene glycol (PEG)with different polymerization degrees as the hydrogen bond acceptors, which are used in the hydration of α-pineneto produce α-terpineol. Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H NMR), and thermogravimetric analysis (TGA) were used to prove the hydrogen bonding between OA and PEG. It is found that the presence of PEG has a less impact on the acid strength of DES. However, an increase in both molecular weight and dosage of PEG results in a decrease in total acidity and catalytic activity.Among them, OA/0.6PEG200, a DES catalyst prepared by PEG with the smallest molecular weight, exhibits a favorable catalytic performance. Under an optimal reaction condition with 0.03 mol of DES (based on OA), 0.06 molof α-pinene, 0.3 mol of water,at 75°C for 8 h, anα-pinene conversion of 81.5% and an α-terpineol selectivity of 51.2% are obtained. The catalyst phase can be separated by refrigerating overnight after reaction and reused directly with relatively stable catalytic performance. Thus, OA/0.6PEG200, as a DES catalyst prepared by a simple and highly atom economical process, will offer a clean catalytic route for the one-step production of α-terpineol.

The deoxygenation reaction is important to produce bio-diesel from esters of fatty acids and/or fatty acids. A novel Ni/beta catalyst with highly dispersed metallic sites, a hierarchical pore structure and a preferable Bronsted/Lewis acid sites ratio is prepared which exhibits deoxygenation and isomerization activities. To realize these goals, a microwave assisted alkaline treatment method was proposed. Compared to the conventional heating method, microwave assisted alkaline treatments are favorable to achieve homogeneous desilication and protect the Bronsted acid sites. When a microwave assisted alkaline treated beta molecular sieve is employed as a support, a decrease of the NiO particle size and the formation of Ni/silicate or aluminate complexes are observed. The deoxygenation of stearic acid shows that the Ni/Beta-2 catalyst has a high selectivity to iso-paraffin (i.e. 33.8%). These results propose a rapid way to prepare hierarchical zeolites using a facile route which are important to produce bio-diesel fractions via deoxygenation reactions.