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Direct production of biodiesel by both esterification and transesterification of renewable oils with acid value (AV) of 9.6-28.9 mg KOH/g using calcined blast furnace dust is studied. Blast furnace dust calcined at 600-700 degrees C obviously promotes efficient biodiesel production because of the crystal form transformation from lead sulfate particles in dust into active lead oxide, lead sulfide, and lead particles. It is found for the first time that lead oxide, lead sulfide and lead particles can resist saponification from fatty acids to catalyze raw renewable oils to biodiesel with catalytic activity order as follows: lead oxide > lead > lead sulfide > lead sulfate. Biodiesel production process is optimized according to an orthogonal design with biodiesel yield of 92 wt% obtained at AV of 9.6 mg KOH/g (82 wt% after 5 cycles). Biodiesel yield of 84 wt% is achieved at AV of 28.9 mg KOH/g with acidity of 0.18 mmol/g. Calcined blast furnace dust presents potential applications in the production of biodiesel from renewable oils with high AVs. (C) 2021 Elsevier Ltd. All rights reserved.

Biodiesel is a type of widely recognized environmentally friendly and sustainable biofuel. The key point for the industrial manufacturing of biodiesel is its cost, especially the price of raw oil feedstocks. Oil feedstocks of low quality require highly effective catalysts with more active sites (e.g., acid, base, acid–base, and enzyme) for (trans)esterification. Metal–organic framework (MOF) is a kind of polyporous material that can control its pore size and topological structure to fit the requirements of the catalytic reactions or conversion routes. This review focuses on the application of MOF-based catalysts in the preparation of biodiesel. Two methods of linking the active sites with MOF are introduced including intermolecular forces and chemical bridging or bonding. Four kinds of MOF-based nanocatalysts (i.e., enzyme, base, acid, and bifunctional catalysts) are evaluated and compared with other heterogeneous catalysts. Besides, technologies such as ultrasound and microwave for MOF-based nanocatalyst applications to produce biodiesel through transesterification and esterification are described. Finally, a brief conclusion and perspective for MOF-based nanocatalyst that applies to biodiesel production are provided. The MOF-based functional catalytic materials show great potential in biodiesel production and other relevant biorefineries.

Background. This study was to investigate the role of adenosine A2A receptors (A2AR) in inhibiting the effect of electroacupuncture (EA) on osteoclastogenesis in collagen-induced arthritis (CIA).Methods. Wistar rats were divided into four groups: sham-control group, CIA-control group, CIA-EA group, and CIA-EA-SCH58261 (A2AR antagonist) group. We detected tumor necrosis factor-α(TNF-α), nuclear transcription factor-κB (NF-κB), receptor activator of NF-κB ligand (RANKL), protein kinase A (PKA), and extracellular regulatory protein kinase 1/2 (ERK1/2) in peripheral blood by ELISA. PKA, ERK1/2, and NF-κB in ankle joints were determined by western blotting. We evaluated the arthritis damage by histological examination and determined the number of osteoclasts by tartrate-resistant acid phosphatase (TRAP) staining.Results. EA treatment downregulated the expression of TNF-α, RANKL, PKA, ERK1/2, and NF-κB in peripheral blood but increased the levels of PKA and ERK1/2 in ankle joints. Importantly, EA treatment reduced bone erosion as evidenced by the histological findings and inhibited osteoclastogenesis as revealed by TRAP staining. All these effects of the EA treatment were reversed by combining EA treatment with the A2AR antagonist SCH58261.Conclusion. Our data suggest that EA treatment activated A2AR. The effects of the A2AR antagonist SCH58261 suggest that the inhibition of osteoclast formation, the inhibition of TNF-α, RANKL, and NF-κB expression, and the increase of ERK1/2 are all dependent on this EA-induced A2AR activation. It is therefore likely that these pathways with clearly defined roles in inflammation and bone erosion are at least partially involved in the mediation of the inhibition of synovitis and osteoclast formation induced by EA.

Solid catalyst (Na2CO3@EFD) was prepared by wet impregnation of electric furnace dust (EFD) in aqueous Na2CO3 solution. It had high basicity and acidity of 0.34 and 0.16 mmol/g for biodiesel production. High biodiesel yield of 99.8 wt% from soybean oil was obtained under the optimized reaction conditions (by Central Composite Design) of 71 °C in 111.36 min with 5.4 wt% catalyst and methanol/oil molar ratio of 11.8/1. After 11 cycles, biodiesel yield still maintained at 90.8 wt% with catalyst recovery rate >90 wt% by magnetic separation of catalyst EFD powders (containing Fe3O4 with magnetism of 59.1 Am2/kg). Pure Na2CO3 particles presented poorer recyclability with lower biodiesel yield of 89.5 wt% even at the eighth cycle by centrifugal separation. Na2CO3@EFD catalyst had high activity and recyclability because: (i) EFD as support hosted nanoparticles of Na2CO3 (30.3 nm) as main base site for transesterification; (ii) porous EFD support provided acidic sites from metal oxides (e.g., ZnO and Al2O3) for esterification; (iii) EFD adsorbed active components into its micropores to maintain high recyclability; and (iv) EFD magnetism from magnetic Fe3O4 kept high efficient magnetic separation. Total metals in the blended biodiesel met the National Standard of China and heavy metals were lower than typical petrochemical diesel. The study provided a practical use of industrial solid waste for the green production of biodiesel.

Jet fuel precursors (4-(2-furyl)-3-buten-2-one (FAc) and 1,5-di-2-furanyl-1,4-pentadien-3-one (F2Ac)) can be produced from aldol condensation between furfural and acetone over basic catalysts. However, there is still a need to develop efficient alkaline catalysts and understand the role of alkaline sites. In this work, La2O2CO3-Al2O3 catalyst was successfully prepared by coprecipitation and the effect of preparation conditions on the properties and catalytic performance was investigated. Experiments showed that La2O2CO3 and La2O3 were formed after calcination, and the activity was greatly improved by the introduction of La2O2CO3. At higher coprecipitation pH, rod-shaped La2O2CO3 was formed, which exhibits higher exposure of basic La3+-O2− sites and shows good performance in aldol condensation reactions. The catalytic performance of La2O2CO3-Al2O3 in aldol condensation of furfural with acetone was also evaluated and compared with that of Al2O3, La2O3, La2O3-Al2O3, La(OH)₃/Al2O3 and La2O2CO3/Al2O3. A total conversion of furfural can be realized with F2Ac yield of 67.8% at a furfural/acetone ratio of 1/1 and 90 °C, with a FAc yield of 25.8% at the same time. The deactivation mechanism of the La2O2CO3-Al2O3 catalyst was also studied.

A heterogeneous CaO/Ag nano catalyst was developed and applied for biodiesel production from transesterification of soybean oil. The silver performed synergistic effects with CaO on promoting biodiesel production. The CaO/Ag nano catalysts exhibited abundant strong basic sites with larger BET surface area (7.02 vs 2.05 m2/g), pore diameter (58.84 vs 37.08 nm) and pore volume (0.070 vs 0.016 cm3/g), which significantly reduced mass transfer resistance of triglycerides during transesterification and improved the mass transfer constants. Response surface methodology was applied to investigate the influence reaction parameters and optimize biodiesel yield. A maximized biodiesel yield of 90.95 ± 2.56 % was achieved using methanol:oil molar ratio of 13, CaO/Ag loading of 5%, reaction time of 90 min and reaction temperature of 72℃. The optimized biodiesel yield for CaO catalyzed transesterification was 88.40 ± 3.34 %, using similar reaction conditions but with 180 min of reaction time. Both nano catalysts were consecutively reused for five times. Kinetic and thermodynamic studies of CaO and CaO/Ag catalyzed transesterification were performed and compared. Economic evaluation of biodiesel production using CaO and CaO/Ag was performed and compared to provide insights for heterogeneous catalyst application for biodiesel production on industrial scale.

Microbial lipids were produced by both rice straw hydrolysates and recycled pretreated glycerol. First, lipid fermentation of glucose via Cryptococcus curvatus was optimized by response surface methodology. Variables were selected by Plackett–Burman design, and optimized by central composite design, achieving 4.9 g/L total lipid and 0.16 g/g lipid yield, and increased further as glucose increased from 30 to 50 g/L. Secondly, after pretreatment, 72% lignin of rice straw was removed with glucose yield increased by 2.4 times to 74% at 20% substrate and 3 FPU/g. Subsequently, its hydrolysates produced high total lipid (8.8 g/L) and lipid yield (0.17 g/g). Finally, recycled glycerol reached the maximum total lipid of 7.2 g/L and high lipid yield of 0.16 g/g. Based on the calculation, 2.9 g total lipid would be produced from 1 g rice straw and the recycled glycerol, with a similar composition to soybean oil.

Biodiesel was directly one-step produced from waste oils without pretreatment catalyzed by a solid base alkalized from spent bleaching clay (SBC) ash. Optimized conditions were obtained with 99.1% biodiesel yield from soybean oil with an orthogonal design. The base catalyst was stable within 8 cycles (>95% biodiesel yield) and resistant to saponification (AV = 9.7 mg KOH/g, 96.5% biodiesel yield). The base was characterized with XRD, EDX-mapping, FT-IR, XRF and TPD, and it had similar strong basicity to Na2SiO3 (0.21 vs. 0.22 mmol/g for Na2SiO3) with active sites of Na2O and CH3ONa evolved from Na2SiO3 and NaAlSiO4 by reactions of NaOH with oxides (e.g., SiO2, Al2O3) in SBC ash. Furthermore, the base was magnetized with magnetism of 6.86 emu/g by carbonizing residual oil in SBC as carbon support and reductant (of Fe2O3 to magnetic Fe3O4 particles). It catalyzed soybean oil to produce biodiesel with 99.2% yield and blended oil (AV = 5.9) to biodiesel with 91.9% yield without any saponification. The catalyst was magnetically separated and reused for 3 cycles with 87% yield. The non-magnetic base could also efficiently catalyze actual SBC oil for the production of biodiesel with 95% yield at AV of 10. This work realized the full use of inorganics in SBC, and its oil for direct biodiesel production at a low temperature (i.e., 65 vs. 120 °C with sulfuric acid process) without wastes produced and results can easily find practical applications for waste oils.

To study the role of adenosine A2A receptor (A2AR) in mediating the anti-inflammatory effect of electroacupuncture (EA) on synovitis in collagen-induced arthritis (CIA), C57BL/6 mice were divided into five treatment groups:Sham-control, CIA-control, CIA-EA, CIA-SCH58261(A2ARantagonist), andCIA-EA-SCH58261. All mice except those in theSham-controlgroup were immunized with collagen II for arthritis induction. EA treatment was administered using the stomach 36 and spleen 6 points, and stimulated with a continuous rectangular wave for 30 min daily. EA treatment and SCH58261 were administered daily from days 35 to 49 (n=10). After treatment, X-ray radiography of joint bone morphology was established at day 60 and mouse blood was collected for ELISA determination of tumor necrosis factor alpha (TNF-α) levels. Mice were sacrificed and processed for histological examination of pathological changes of joint tissue, including hematoxylin-eosin staining and immunohistochemistry ofA2ARexpression. EA treatment resulted in significantly reduced pathological scores, TNF-αconcentrations, and bone damage X-ray scores. Importantly, the anti-inflammatory and tissue-protective effect of EA treatment was reversed by coadministration of SCH58261. Thus, EA treatment exerts an anti-inflammatory effect resulting in significant protection of cartilage by activation ofA2ARin the synovial tissue of CIA.

Rice straw was pretreated with glycerol and AlCl3 for enzymatic hydrolysis at low cellulase loadings. Based on a central composite design, 83% delignification, 94% hemicellulose removal, and 92% cellulose recovery (or 76% cellulose in solid residue) were achieved under the optimized pretreatment conditions (0.08 mol/L AlCl3 as catalyst at 146.8 °C for 20 min with 90% glycerol). During glycerol-AlCl3 pretreatment, the lignin-carbohydrate complex was depolymerized, resulting in the complex and recalcitrant construction of straw effectively being destroyed. The enzyme adsorption ability of pretreated straw was 16.5 times that for the original sample. After pretreatment, glucose yield was increased by 2.4 times to 74% for 48 h. Moreover, concentrated solid (15%) with low cellulase loading (3.3 FPU/g dry substrate) achieved 58.6% glucose yield, and further increased by 12% to 65.7% by adding Tween 80. Glycerol-AlCl3 pretreatment was a promising approach to realize high-concentrated solid hydrolysis for sugars at low cellulase loadings.

Objective To explore better therapies for the treatment of frozen shoulder. Methods One hundred and seventy-four cases were divided into a filiform needle group (56 cases), an electroacupuncture group (57 cases) and a warming needle group (61 cases) according to the randomized, controlled and single-blind study principles. Jiānqian ( Extra), Jiānyu ( LI 15), Jiānliao ( TE 14), Naoshū ( SI 10), Waiguān ( TE 5), Hegŭ ( LI 4) were used in all three groups but treated with filiform needle, electroacupuncture and warming needle technique respectively. The needles were retained for 30 min. It was given once every other day and 5 times constituted as one course. Pain indices and activity degree of shoulders were measured and recorded before and after treatment every time. Results The total effective rate was 93.0% (53/57) in the electroacupuncture group and 95.1% (58/61) in the warming needle group, both superior to that of 78.6% (44/56) in the filiform needle group (both P P >0.05). After one course of treatment, the decline indices of shoulder pain of electroacupuncture group (4.28±0.22) and warming needle group (3.74±0.17) were both significantly greater than that of filiform needle group (2.7810.18) (both P P P P P Conclusion All these three acupuncture therapies can achieve good therapeutic effects for frozen shoulder. The therapeutic effects of electroacupuncture and warming needle groups are superior to that of filiform needle group. All these three therapies could significantly reduce patients' pain and improve their shoulder activity degree. The analgesic effect of electroacupuncture is the best, and the shoulder activity degree improved by warming needle is the best. The improvement of clinical therapeutic effect mainly depends on the therapy and the treatment times when the same acupoints are selected and the condition of illness are similar.

Transcutaneous acupoint electrical stimulation (TEAS) is a standard therapy for painful conditions. This study evaluated pain-relieving effects of treatment with TEAS before and after surgical abortion.In this cohort study 140 nulliparae requesting pregnancy termination with intravenous anesthesia from August to December 2013 at the outpatient clinic of Wenzhou Medical University First Affiliated Hospital were recruited and divided into three cohorts who received TEAS pre-, post-, and both pre- and post-operation, alongside a control group. The cohorts underwent TEAS treatment for 30 min before and/or after the procedure while the control group received no TEAS treatment. Pain levels were evaluated upon recovery at 10, 30, and 45 min, respectively, after abortion.Mean Visual Analog Scale (VAS) scores in pre-operation cohorts, but not the post-operation cohort, were significantly lower than those obtained for the control group at 10 min (p 0.01). VAS scores at 30 min and 45 min postoperatively were similar in each cohort but lower than control values (p 0.001). More cohort patients reported mild or no pain than control patients (p 0.05); the pre-operation cohorts had more women with no pain compared with the post-operation group (p 0.05). There were no differences among groups in medical treatment required after 45 min. There were fewer complications of nausea and vomiting in the cohorts compared with the control group (p 0.05).Performing TEAS before and after surgical abortion provides postoperative pain relief. However, receiving TEAS before surgery allowed more women to experience mild or no pain.Transcutaneous acupoint electrical stimulation shows potential as an adjunct to conventional pain treatment following surgical abortion in nulliparae.