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1.
Molecules ; 29(9)2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38731653

RESUMO

In pursuit of enhancing the mechanical properties, especially the tensile strength, of 4D-printable consumables derived from waste cooking oil (WCO), we initiated the production of acrylate-modified WCO, which encompasses epoxy waste oil methacrylate (EWOMA) and epoxy waste oil acrylate (EWOA). Subsequently, a series of WCO-based 4D-printable photocurable resins were obtained by introducing a suitable diacrylate molecule as the second monomer, coupled with a composite photoinitiator system comprising Irgacure 819 and p-dimethylaminobenzaldehyde (DMAB). These materials were amenable to molding using an LCD light-curing 3D printer. Our findings underscored the pivotal role of triethylene glycol dimethacrylate (TEGDMA) among the array of diacrylate molecules in enhancing the mechanical properties of WCO-based 4D-printable resins. Notably, the 4D-printable material, composed of EWOA and TEGDMA in an equal mass ratio, exhibited nice mechanical strength comparable to that of mainstream petroleum-based 4D-printable materials, boasting a tensile strength of 9.17 MPa and an elongation at break of 15.39%. These figures significantly outperformed the mechanical characteristics of pure EWOA or TEGDMA resins. Furthermore, the EWOA-TEGDMA resin demonstrated impressive thermally induced shape memory performance, enabling deformation and recovery at room temperature and retaining its shape at -60 °C. This resin also demonstrated favorable biodegradability, with an 8.34% weight loss after 45 days of soil degradation. As a result, this 4D-printable photocurable resin derived from WCO holds immense potential for the creation of a wide spectrum of high-performance intelligent devices, brackets, mold, folding structures, and personalized products.

2.
RSC Adv ; 12(55): 36018-36027, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36545106

RESUMO

To provide low-cost wax and a new methodology for utilizing waste cooking oil (WCO), fatty acid wax based on WCO was synthesized by using epoxidation and hydrolysis treatments, whose properties included melting point, color, hardness, combustion properties, aldehyde content, and microscopic morphology were tested and analyzed. The obtained WCO-based wax contained mixed fatty acids, including palmitic acid and 9,10-dihydroxystearic acid as main constituents, which could form a 3D stable crossing network constructed by large long-rod crystals. The WCO-based wax with high fatty acid content (96.41 wt%) has a high melting point (44-53 °C), light color (Lovibond color code Y = 11.9, R = 2.3), good hardness (needle penetration index = 2.66 mm), long candle burning time (293 min), and low aldehyde content (7.98 × 10-2 µg g-1), which could be a lower-cost alternative of commercial soybean wax (SW) for producing various wax products including candles, crayons, waxworks, etc.

3.
RSC Adv ; 12(36): 23692-23703, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36090407

RESUMO

To provide a low-cost photocatalyst and new methodology for the utilization of waste rice noodle (WRN), a carbon quantum dots/zinc oxide (CQDs/ZnO) composite using WRN as the raw material was synthesized and characterized. The CQDs/ZnO composite based on WRN exhibited a highly efficient photocatalytic degradation effect on various organic pollutants and could be a good alternative for commercial ZnO. For methylene blue, the CQDs/ZnO composite showed a good degradation rate of 99.58% within 40 min, a high degradation rate constant of 0.2630 min-1, and could be recycled and reused for ten photocatalytic cycles without an appreciable decrease in the degradation effect, which was much better than that of commercial ZnO. The resulting CQDs/ZnO composite also displayed a nice photocatalytic degradation effect on other common organic pollutants, such as malachite green, methyl violet, basic fuchsin, rhodamine B, aniline and tetracycline. In particular, it could achieve excellent photocatalytic degradation on malachite green with an extremely high degradation rate constant of 1.9260 min-1. Besides, the CQDs/ZnO composite could also be used to control the pollution of tetracycline or aniline. The introduction of CQDs based on WRN to ZnO resulted in efficient electron-hole pair separation and enabled more photogenerated electrons to reduce O2 and more photogenerated holes to oxidize H2O, which caused stronger abilities in producing radicals (such as O2˙- and ˙OH) and a better photocatalytic degradation effect to organic pollutants.

4.
RSC Adv ; 12(6): 3365-3371, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35425352

RESUMO

In this work, a cost-effective wax was synthesized from waste cooking oil (WCO), and its properties including melting point, color, hardness, combustion performance and micro-morphology were tested and analyzed. The obtained results showed that the epoxy waste cooking oil had lighter color, higher melting point and hardness than that of original WCO, which could be used as wax. Moreover, introducing stearic acid further improved the performances of WCO-based wax. The WCO-based wax made of epoxy waste cooking oil and stearic acid (containing ≥50 wt% stearic acid) displayed a relatively high melting point (≥46 °C), light color (Lovibond color code Y ≤ 16.1, R ≤ 2.3), good hardness (needle penetration index ≤2.95 mm) and long combustion time (≥227 min), and could achieve the required national standard and be used as a substitute for the commercially available soybean wax. Together with many additional benefits such as low synthesis cost, mild reaction conditions, convenient synthesis route, and no secondary pollution, producing wax based on WCO could provide a new path for WCO recycling in economically trailing regions.

5.
Waste Manag ; 85: 295-303, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30803583

RESUMO

Solid alcohols based on waste cooking oil (WCO) and other edible oils (butter or soybean oil) were synthesized by a simple one-step method. The effects of sodium hydroxide (NaOH) dosage and type of oil on the combustion performances were explored. IR spectroscopy and micro-morphologies of the oil based solid alcohols were also studied. Results showed that, for oil based solid alcohol, use of an appropriate excess of NaOH and an oil with lower iodine value produced the solid alcohol with better combustion performance. Centrifugation produced the bottom waste cooking oil (B-WCO) with lower iodine value and the supernatant waste cooking oil (S-WCO) with higher iodine value. The B-WCO afforded solid alcohol with longer combustion time, higher melting temperature and relatively low combustion residue rate, whereas the S-WCO could be used for synthesizing biodiesel.


Assuntos
Biocombustíveis , Óleos de Plantas , Culinária , Etanol , Alimentos
6.
Acta Diabetol ; 50(1): 89-92, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21080005

RESUMO

A 59-year-old Chinese male patient was admitted at diagnosis of type 1 diabetes with ketoacidosis. During the normalization of blood glucose with insulin, the patient developed acute hemolysis. The factors predisposing to hemolysis were not found, except the significantly diminished activity of glucose-6-phosphate dehydrogenase (G6PD). DNA analysis did not show any coding or intronic mutation in the G6PD gene. This is the first reported case of a Chinese patient in diabetic ketoacidosis with hemolysis induced by G6PD deficiency in the absence of mutations in the G6PD gene.


Assuntos
Diabetes Mellitus Tipo 1/enzimologia , Cetoacidose Diabética/enzimologia , Deficiência de Glucosefosfato Desidrogenase/metabolismo , China , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patologia , Cetoacidose Diabética/etiologia , Cetoacidose Diabética/genética , Cetoacidose Diabética/patologia , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Deficiência de Glucosefosfato Desidrogenase/complicações , Deficiência de Glucosefosfato Desidrogenase/genética , Deficiência de Glucosefosfato Desidrogenase/patologia , Hemólise , Humanos , Masculino , Pessoa de Meia-Idade
7.
Chem Commun (Camb) ; 48(4): 552-4, 2012 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-22068261

RESUMO

A novel supramolecular plaster, (AEDPH(3))·(BtaH) (1), is synthesised and characterized. The supramolecular plaster is easy to synthesise and process, and displays good mechanical properties. It can adsorb and eliminate formaldehyde (HCHO) with high efficiency and exhibits very interesting HCHO/ultraviolet ray-induced luminescence switching.


Assuntos
Ácido Aminoetilfosfônico/química , Poluentes Ambientais/isolamento & purificação , Formaldeído/isolamento & purificação , Triazóis/química , Adsorção , Luminescência , Modelos Moleculares , Raios Ultravioleta
8.
Chemistry ; 16(8): 2619-27, 2010 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-20077543

RESUMO

A convenient and waste-free synthesis of indene-based tertiary carbinamines by rhodium-catalyzed imine/alkyne [3+2] annulation is described. Under the optimized conditions of 0.5-2.5 mol % [{(cod)Rh(OH)}(2)] (cod=1,5-cyclooctadiene) catalyst, 1,3-bis(diphenylphosphanyl)propane (DPPP) ligand, in toluene at 120 degrees C, N-unsubstituted aromatic ketimines and internal alkynes were coupled in a 1:1 ratio to form tertiary 1H-inden-1-amines in good yields and with high selectivities over isoquinoline products. A plausible catalytic cycle involves sequential imine-directed aromatic C-H bond activation, alkyne insertion, and a rare example of intramolecular ketimine insertion into a Rh(I)-alkenyl linkage.

9.
Artigo em Chinês | MEDLINE | ID: mdl-21158157

RESUMO

AIM: To study the effect of angiotensin-(1-7) on the kidney of diabetic rats by observing the mRNA expression of PDGF and TGF-beta1. METHODS: SD rats were divided into three groups: Group C (uni-nephrectomy control group), Group D (diabetic model control group), Group T (Ang-(1-7) treated group). We evaluated blood glucose,urea nitrogen, creatinine and urine albumin excretion respectively, studied the renal morphology by light microscope, and detected the gene expression of PDGF, TGF-beta1 in renal tissue by RT-PCR technique. RESULTS: There was significant difference between the group D and T about the RW/BW, renal morphology, the total urine protein and the mRNA expression of PDGF and TGF-beta1. CONCLUSION: Ang-(1-7) can relieve the renal process of diabetic rats.


Assuntos
Angiotensina I/farmacologia , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/metabolismo , Fragmentos de Peptídeos/farmacologia , Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Rim/metabolismo , Rim/patologia , Masculino , Fator de Crescimento Derivado de Plaquetas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Crescimento Transformador beta1/genética
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