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1.
Opt Lett ; 49(9): 2413-2416, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38691732

RESUMEN

A novel, to the best of our knowledge, cross-spectral optical computing imaging experiment has been achieved through a single exposure of a charge-coupled device. The experimental setup integrates single-pixel imaging (SPI) with ghost imaging (GI) through a photoelectric conversion circuit and a synchronous modulation system. The experimental process involves modulation in one wavelength band (in SPI) and demodulation using the GI algorithm in another. Significantly, our approach utilizes optical computing demodulation, a departure from the conventional electronic demodulation in GI (SPI), which involves the convolution between the bucket optical signals and the modulated patterns on the digital micromirror device. A proof-of-concept cross-band imaging experiment from near-infrared to visible light has been carried out. The results highlight the system's ability to capture images at up to 20 frames per second using near-infrared illumination, which are then reconstructed in the visible light spectrum. This success not only validates the feasibility of our approach but also expands the potential applications in the SPI or GI fields, particularly in scenarios where two-dimensional detector arrays are either unavailable or prohibitively expensive in certain electromagnetic spectra such as x-ray and terahertz.

2.
Int J Mol Sci ; 19(1)2017 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-29267210

RESUMEN

The lignin-carbohydrate complex (LCC) was isolated from milled wood lignin of 2- and 24-month-old crude bamboo (Neosinocalamus affinis) culms using acetic acid (AcOH) and then characterized. The results have shown that the LCC preparation from 2-month-old bamboo (L2) exhibited a slightly lower molecular weight than the LCC preparation from the 24-month-old bamboo (L24). Further studies using Fourier transform infrared spectroscopy (FT-IR) and heteronuclear single quantum coherence (2D-HSQC) NMR spectra analyses indicate that the LCC preparations included glucuronoarabinoxylan and G-S-H lignin-type with G>S>>H. The content of the S lignin units of LCC in the mature bamboo was always higher than in the young bamboo. Combined with sugar composition analysis, the contents of phenyl glycoside and ether linkages in the L24 preparation were higher than in the L2 preparation; however, there was a reverse relationship of ester LCC bonds in L2 and L24. Lignin-xylan was the main type of LCC linkage in bamboo LCCs. Lignin-lignin linkages in the LCC preparations included ß-ß, ß-5 and ß-1 carbon-to-carbon, as well as ß-O-4 ether linkages, but ß-1 linkages were not present in L2.


Asunto(s)
Bambusa/química , Carbohidratos/química , Lignina/química , Sustancias Macromoleculares/química , Madera/química , Ácido Acético/química , Conformación de Carbohidratos , Estructura Molecular , Peso Molecular , Xilanos/química
3.
Appl Opt ; 54(25): 7494-9, 2015 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-26368868

RESUMEN

The Hanbury Brown and Twiss (HBT) effect is a classical intensity correlation effect, but it is also widely used in the quantum optics regime, and has led to many important breakthroughs in both basic and applied physics, among which ghost imaging (GI) has aroused particular interest. In this article, the positive and negative intensity correlations in HBT correlation are analyzed, based on which we describe experiments on thermal light nonlocal imaging of a reflective object using the positive and negative correlations of correspondence imaging. An improvement of 16.3% in the signal-to-noise ratio of the reconstructed image has been achieved, indicating that this method may have promising potential in future GI applications where noise is a serious problem and smaller sampling numbers are necessary.

4.
Opt Express ; 22(20): 24268-75, 2014 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-25322001

RESUMEN

We present a new technique to denoise ghost imaging (GI) in which conventional intensity correlation GI and an iteration process have been combined to give an accurate estimate of the actual noise affecting image quality. The blurring influence of the speckle areas in the beam is reduced in the iteration by setting a threshold. It is shown that with an appropriate choice of threshold value, the quality of the iterative GI reconstructed image is much better than that of differential GI for the same number of measurements. This denoising method thus offers a very effective approach to promote the implementation of GI in real applications.

5.
Opt Express ; 22(6): 7133-44, 2014 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-24664061

RESUMEN

Compressed sensing is a theory which can reconstruct an image almost perfectly with only a few measurements by finding its sparsest representation. However, the computation time consumed for large images may be a few hours or more. In this work, we both theoretically and experimentally demonstrate a method that combines the advantages of both adaptive computational ghost imaging and compressed sensing, which we call adaptive compressive ghost imaging, whereby both the reconstruction time and measurements required for any image size can be significantly reduced. The technique can be used to improve the performance of all computational ghost imaging protocols, especially when measuring ultra-weak or noisy signals, and can be extended to imaging applications at any wavelength.

6.
J Opt Soc Am A Opt Image Sci Vis ; 31(9): 2105-8, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25401452

RESUMEN

A modified Nth-order correlation function is derived that can effectively remove the noise background encountered in high-order thermal light ghost imaging (GI). Based on this, the quality of the reconstructed images in an Nth-order lensless GI setup has been greatly enhanced compared to former high-order schemes for the same sampling number. In addition, the dependence of the visibility and signal-to-noise ratio for different high-order images on the sampling number has been measured and compared.

7.
Int J Biol Macromol ; 264(Pt 1): 130417, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38417744

RESUMEN

Cellulose-rich straws of corn and rice were torrefied under carbon dioxide, and the fuel characteristics and combustion performance of the obtained biochar were investigated. A high severity resulted in surface collapse, greater pore volume, elimination of oxygen, elevated calorific value, and improved hydrophobicity in biochar. Following carbon dioxide torrefaction, the cellulose content in solid biochar experienced a slight decrease when the temperature was raised to 220 °C for longer residence durations. At 300 °C, the cellulose content in the biochar was nearly eliminated, while the relative proportion of non-sugar organic matter in corn stover and rice straw increased to 87.40 % and 77.27 %, respectively. The maximum calorific values for biochar from corn and rice straws were 22.38 ± 0.03 MJ/kg and 18.72 ± 0.05 MJ/kg. The comprehensive combustion indexes of rice and corn straw samples decreased to 1.06 × 10-7 and 1.31 × 10-7 after torrefaction at 300 °C, respectively. In addition, the initial decomposition temperatures increased by 38 °C and 45 °C, while the ultimate combustion temperatures rose by 13 °C and 16 °C for corn and rice straws, respectively. These results imply an extended combustion timeframe for the torrefied samples.


Asunto(s)
Dióxido de Carbono , Celulosa , Carbón Orgánico , Biomasa , Temperatura
8.
Bioresour Technol ; 384: 129365, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37343804

RESUMEN

A green and effective method is proposed for the pretreatment of eucalyptus by freeze-thaw assisted maleic acid tactic, wherein the effects of freeze-thaw, maleic acid concentration, reaction time, and temperature on the fractionation were examined. Results showed that under optimal conditions (60% maleic acid, 120 °C, and 2 h), a remarkable removal of 74.5% lignin and 95.2% hemicellulose was achieved after freeze-thaw treatment. The resulting cellulose-rich solid residues were further processed with maleic acid to prepare cellulose nanocrystals, which displayed uniform sized rod-like structures and high crystallinity (62.51%). Moreover, maleic acid pretreatment resulted in lignin with low molecular weight (2110-2530) and excellent homogeneity (PDI ≤ 1.86), while maintaining a relatively intact structure. The lignin had high ß-O-4 aryl ether bond contents (≥77.5%) and abundant phenolic hydroxyl contents (2.33-3.63 mmol/g). Overall, the process exhibits notable benefits in effectively separating lignocellulose for high valorization.


Asunto(s)
Eucalyptus , Nanopartículas , Celulosa , Lignina/química , Eucalyptus/química , Hidrólisis
9.
Nanoscale ; 15(40): 16447-16457, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37791568

RESUMEN

High entropy alloys (HEAs) are promising nuclear structural materials due to their excellent irradiation resistance. However, the essential mechanisms of irradiation tolerance in HEAs remain largely inferential and imperfectly understood. This study investigates the evolution of irradiation-induced nano-scale microstructures in Ni, FeNiCr, FeNiCrCoCu and FeNiCrCuAl HEA models by molecular dynamics simulations to elucidate the conundrums. As fewer irradiation-induced Frenkel pair (FP) residuals were found in the FeNiCrCuAl HEA model in comparison with other models, a high resistance of the HEAs to the generation of permanent defects was indicated, while also the associated relatively long thermal spike and slow recrystallization stimulated a high efficiency for the recombination/annihilation of FPs to underscore a superior structural recovery of the HEAs. Under the influence of compositional increases of constituent elements, the effect of severe lattice distortion by energetics modifications was found to stimulate decreased atomic mobility accompanied by inhibited dislocation formation. The evolution of the models' lattices in terms of their capacity to restrict interstitials and repair defects revealed that the self-healing/recovery mechanism that confirmed the highest initial lattice distortion value accompanied by the least lattice re-distortion value in the FeNiCrCuAl HEA model is key to the observed superior irradiation tolerance of the HEA models. Thus, by feasibly enhancing lattice distortion in crystalline materials, notably in HEAs, promising and potentially high irradiation-resistant structural materials can be developed.

10.
Int J Biol Macromol ; 253(Pt 4): 127012, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37734524

RESUMEN

Lignin nanoparticles (LNPs) were synthesized using an anti-solvent method and subsequently loaded with manganese dioxide (MnO2) via potassium permanganate treatment, resulting in the formation of MnO2@LNPs. An extensive investigation was conducted to elucidate the influence of MnO2@LNPs on the decolorization of methyl orange solution. The LNPs were successfully obtained by adjusting the preparation parameters, yielding particles exhibited average sizes ranging from 300 to 600 nm, and the synthesis process exhibited a high yield of up to 87.3% and excellent dispersion characteristics. Notably, LNPs size was reduced by decreasing initial concentration, increasing stirring rate, and adding water. In the acetone-water two-phase system, LNPs self-assembled into spherical particles driven by π-π interactions and hydrogen bond forces. Oxidation modification using potassium permanganate led to the formation of nanoscale MnO2, which effectively combined with LNPs. Remarkably, the resulting MnO2@LNPs demonstrated a two-fold increase in methyl orange adsorption capacity (227 mg/g) compared to unmodified LNPs. The process followed the Langmuir isotherm model and was exothermic.


Asunto(s)
Nanopartículas , Óxidos , Óxidos/química , Compuestos de Manganeso/química , Permanganato de Potasio , Lignina/química , Adsorción , Agua , Nanopartículas/química
11.
Food Chem ; 134(3): 1392-8, 2012 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25005958

RESUMEN

Microwave-assisted extraction in organic acid aqueous solution (formic acid/acetic acid/water, 3/5/2, v/v/v) was applied to isolate lignin from bamboo. Additionally, the structural features of the extracted lignins were thoroughly investigated in terms of C9 formula, molecular weight distribution, FT-IR, (1)H NMR and HSQC spectroscopy. It was found that with an increase in the severity of microwave-assisted extraction, there was an increase of phenolic hydroxyl content in the lignin. In addition, an increase of the severity resulted in a decrease of the bound carbohydrate content as well as molecular weight of the lignin. Antioxidant activity investigation indicated that the radical scavenging index of the extracted lignins (0.35-1.15) was higher than that of BHT (0.29) but lower than that of BHA (3.85). The results suggested that microwave-assisted organic acid extraction provides a promising way to prepare lignin from bamboo with good antioxidant activity for potential application in the food industry.


Asunto(s)
Antioxidantes/química , Antioxidantes/farmacología , Lignina/química , Lignina/farmacología , Microondas , Poaceae/química , Ácido Acético/química , Antioxidantes/aislamiento & purificación , Fraccionamiento Químico/métodos , Formiatos/química , Lignina/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Estructura Molecular , Oxidación-Reducción , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Espectroscopía Infrarroja por Transformada de Fourier
12.
Sci Rep ; 12(1): 7999, 2022 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-35568695

RESUMEN

There are limited studies investigating the combined effects of biological, environmental, and human factors on the activity of the domestic dog. Sled dogs offer a unique opportunity to examine these factors due to their close relationship with handlers and exposure to the outdoors. Here, we used accelerometers to measure the activity of 52 sled dogs over 30 days from two locations in Canada. The two locations differ in the working demands of dogs, therefore we used linear mixed effects models to assess how different factors impact daytime and nighttime activity of working versus nonworking dogs. During the daytime, we found that males were more active than females among nonworking dogs and younger dogs were more active than older dogs among working dogs. Alaskan huskies had higher activity levels than non-Alaskan husky breeds in working sled dogs during the day. Nonworking dogs were slightly more active during colder weather, but temperature had no effect on working dogs' activity. The strongest predictor of daytime activity in working dogs was work schedule. These results indicate that the influence of biological factors on activity varied depending on dogs' physical demands and human activity was the most powerful driver of activity in working dogs.


Asunto(s)
Condicionamiento Físico Animal , Perros de Trabajo , Animales , Cruzamiento , Canadá , Perros , Femenino , Masculino
13.
Int J Biol Macromol ; 204: 364-372, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35149095

RESUMEN

Formic acid is an attractive solvent for the fractionation of lignocellulose for the production of biomaterials and chemicals, while the operation conducted in a batch manner is not conducive to mass transfer in separation process. In this research, eucalyptus was fractionated with formic acid/hydrochloric solution in a flow-through reactor at 95 °C, and the structural characteristics and the composition of fractionated lignin in different stages were investigated. Results showed that the fractionation efficiency was notably improved with a flow-through reactor, as evidenced by the low solid residue yield of 49.5% and the lignin removal rate of 79.4% as compared to the batch manner. During the fractionation process, the dissolution rate of lignin decreased gradually, and the obtained lignin samples showed low molecular weight (<3000), good uniformity (<2), and high thermal stability. The structure analysis showed that ß-O-4, ß-ß, and ß-5 linkages in lignin were degraded to varying degrees with increased time, and the degradation of G units was more severe than S ones.


Asunto(s)
Eucalyptus , Lignina , Fraccionamiento Químico , Eucalyptus/química , Formiatos , Lignina/química
14.
Bioresour Technol ; 354: 127139, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35405215

RESUMEN

Novel and green cholinium amino acids-based deep eutectic solvents (DESs) and their aqueous mixtures were synthesized and employed in deconstructing poplar for hemicellulose fractionation. The effects of water content in DESs on hemicellulose dissociation and structural features were comprehensively investigated, along with the reusability of DESs for treatment. The integration of water into DESs could facilitate hemicellulose fractionation, and the cholinium lysine: urea with 5 wt% water (CL: U-5) demonstrated the best performance with a hemicellulose yield of 59.2%. Further structure analysis revealed that hemicelluloses with various branching degrees and molecular weights were obtained with varying water content of DESs. Furthermore, the CL: U-5 had recyclability and reusability with a 40.5% hemicellulose yield obtained after reused three times. The novel and eco-friendly cholinium amino acids-based DESs treatment provides an effective and sustainable strategy for hemicellulose fractionation from woody biomass.


Asunto(s)
Aminoácidos , Disolventes Eutécticos Profundos , Biomasa , Polisacáridos , Solventes/química , Agua
15.
World J Gastroenterol ; 28(33): 4890-4908, 2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36156925

RESUMEN

BACKGROUND: Chronic gastritis (CG) is an inflammatory disease of the gastric mucosa. Shen-ling-bai-zhu san (SLBZS), a traditional Chinese medicine formula, is widely used for treating CG. Nevertheless, its effects are currently unclear. AIM: To determine the clinical evidence and potential mechanisms of SLBZS for the treatment of CG. METHODS: We systematically searched 3 English (PubMed, Embase, Medline) and 4 Chinese databases (Cochrane Library Central Register of Controlled Trials, China National Knowledge Infrastructure database, Wanfang Data Knowledge Service Platform, and the VIP information resource integration service platform) without language or publication bias restriction. Qualified studies were selected according to pre-set inclusion and exclusion criteria. RevMan 5.3 software was used for meta-analysis and literature quality assessment, Stata 14.0 software was used for sensitivity analysis, GRADE profiler 3.6 was used to evaluate the quality of evidence. And then, network pharmacology analysis was applied to primary research the mechanisms of action of SLBZS on CG. RESULTS: Fourteen studies were finally included, covering 1335 participants. Meta-analysis indicated that: (1) SLBZS was superior to conventional therapies [risk ratio (RR): 1.29, 95% confidence interval (CI): 1.21 to 1.37, P < 0.00001]; (2) SLBZS was better than conventional therapies [RR: 0.24, 95% confidence interval (95%CI): 0.11 to 0.55, P = 0.0007] in terms of recurrence rate and reversal of Helicobacter pylori positivity (RR: 1.20, 95%CI: 1.11 to 1.30, P < 0.00001); and (3) The safety of SLBZS for CG remains unclear. According to the GRADE method, the quality of evidence was not high. Besides, SNZJS might treat CG by acting on related targets and pathways such as EGFR tyrosine kinase inhibitor resistance, the PI3K-Akt signaling pathway, and others. CONCLUSION: SLBZS might be useful in treating CG, but long-term effects and specific clinical mechanisms of it maintain unclear. More samples and high-quality clinical experiments should be assessed and verified in the next step.


Asunto(s)
Medicamentos Herbarios Chinos , Gastritis , Medicamentos Herbarios Chinos/efectos adversos , Receptores ErbB , Gastritis/tratamiento farmacológico , Humanos , Lenguaje , Fosfatidilinositol 3-Quinasas , Inhibidores de Proteínas Quinasas , Proteínas Proto-Oncogénicas c-akt
16.
Bioresour Technol ; 342: 126035, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34592454

RESUMEN

Abundant, environmentally friendly, and sustainable lignocellulose is a promising feedstock for replacing fossil fuels, and hydrothermal liquefaction is an effective technology to convert it into liquid fuels and high-value chemicals. This review summarizes and discusses the reaction mechanism, main influence factor and the production application of hydrothermal liquefaction. Particular attention has been paid to the reaction mechanism of the structural components of lignocellulose, i.e., cellulose, hemicellulose, and lignin. In addition, the influence factors including types of lignocellulose, temperature, heating rate, retention time, pressure, solid-to-liquid ratio, and catalyst are discussed in detail. The limitations in the hydrothermal liquefaction of lignocellulose and the prospects are proposed. This provides deep knowledge for understanding the process as well as the development of advanced products from lignocellulose.


Asunto(s)
Biocombustibles , Lignina , Biomasa , Temperatura , Agua
17.
World J Emerg Med ; 12(1): 48-53, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33505550

RESUMEN

BACKGROUND: This study aims to investigate whether small balloon aortic valvuloplasty (BAV) reduces the need for permanent pacemaker implantation (PPMI) after transcatheter aortic valve implantation (TAVI). METHODS: This was a retrospective analysis using data from our local TAVI database. Small BAV was defined as a small balloon size (=18 mm) pre-dilatation. Normal BAV was defined as a balloon size >18 mm. The primary endpoint was the incidence of new PPMI. RESULTS: Of 99 consecutive TAVI patients, five patients were excluded due to pre-existing permanent pacemaker. Patients in the small BAV group (n=57) had a significantly lower PPMI rate compared with the normal BAV group (n=37) (3.5% vs. 18.9%, P=0.026). Moderate or severe aortic valve regurgitation post-procedure was similar between the small BAV and normal BAV groups (5.3% vs. 8.1%, P=0.480); likewise, the mean aortic gradient post-procedure did not differ significantly (11.5±5.2 mmHg vs. 12.2±7.3 mmHg, 1 mmHg=0.133 kPa, P=0.580) between the groups. Device success rates were also similar (94.7% vs. 91.8%, P=0.680). In multivariable analysis, small BAV (P=0.027), the ratio of prosthesis diameter to annulus diameter (P=0.048), and mean aortic gradient by echo in the basement (P=0.021) were independent predictors of PPMI. CONCLUSIONS: The small BAV strategy is associated with a low rate of permanent pacemaker implantation after transcatheter self-expanding valve implantation in this single-center observational study.

18.
Sci Bull (Beijing) ; 66(2): 133-138, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36654220

RESUMEN

Neutron imaging is an invaluable tool for noninvasive analysis in many fields. However, neutron facilities are expensive and inconvenient to access, while portable sources are not strong enough to form even a static image within an acceptable time frame using traditional neutron imaging. Here we demonstrate a new scheme for single-pixel neutron imaging of real objects, with spatial and spectral resolutions of 100 µm and 0.4% at 1 Å, respectively. Low illumination down to 1000 neutron counts per frame pattern was achieved. The experimental setup is simple, inexpensive, and especially suitable for low intensity portable sources, which should greatly benefit applications in biology, material science, and industry.

19.
Zhonghua Yan Ke Za Zhi ; 46(5): 415-8, 2010 May.
Artículo en Zh | MEDLINE | ID: mdl-20654214

RESUMEN

OBJECTIVE: To evaluate the clinical effectiveness and accommodative range after implanting the 1CU. METHODS: It was a prospective case series study. From March in 2004 to December in 2007, 23 cases (28 eyes) had phacoemulsification and implantation of 1CU (HumanOptics). Naked and best corrected distant acuity, Naked acuity at 35 cm and best corrected near, the amplitude of accommodation measured with subjective and objective techniques and the change in the anterior chamber depth were measured at 3-6 months, 18-24 months and over 36 months after surgery. RESULTS: After implantation, the 1CU had good centered and stable and no IOL-specific complications. Naked distant acuity of the three groups are 0.84+/-0.23, 0.81+/-0.19 and 0.78+/-0.17, between them there are no significantly statistical differences (F=0.759, P>0.05). The best corrected distant acuity of the three groups were 0.97+/-0.13, 0.99+/-0.17 and 1.00+/-0.17, between them there are no significantly statistical differences (F=0.17, P>0.05). The near acuity at 35 cm was 0.66+/-0.24, 0.52+/-0.14 and 0.47+/-0.12, between them there are significantly statistical differences (F=9.312, P<0.01). The best corrected near acuity were 0.97+/-0.13, 0.94+/-0.22 and 0.90+/-0.21, between them there are no significantly statistical differences (F=0.915, P>0.05). The accommodative range measured with subjective were 0.89+/-0.34, 0.72+/-0.17 and 0.56+/-0.16, between them there are significantly statistical differences (F=13.43, P<0.01). The accommodative range measured with objective were 3.58+/-0.54, 3.01+/-0.89 and 2.50+/-0.54, between them there were significantly statistical differences (F=17.886, P<0.01). The anterior chamber depth measured by application of 2% pilocarpine eyedrops were 0.88+/-0.40, 0.54+/-0.23 and 0.33+/-0.20, between them there were significantly statistical differences (F=26.589, P<0.01). CONCLUSIONS: The eyes with 1CU have good visual acuity and increased accommodative range more than the single-focus IOL. With the extension of time after surgery, the ability of 1CU regulation gradually declines, and nears point swift away gradually.


Asunto(s)
Catarata/terapia , Implantación de Lentes Intraoculares , Facoemulsificación , Acomodación Ocular , Anciano , Femenino , Estudios de Seguimiento , Humanos , Lentes Intraoculares , Masculino , Persona de Mediana Edad , Estudios Prospectivos
20.
Int J Biol Macromol ; 164: 4662-4670, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32941904

RESUMEN

Understanding the structure and properties of lignin has important practical significance for its further applications. In this case, eucalyptus was fractionated with 88% formic acid at 101 °C for different durations, and the removal efficiency as well as the chemical structure of lignin at various stages were comparatively analyzed. The obtained data indicated that with increasing reaction time, lignin was continuously removed and the process could be divided into three stages. The lignin dissolution rate was fast first and then slow, and the molecular weight of the dissolved lignin increased with time. The lignin structure was condensed and the molecular weight increased with prolonged of reaction time. Structural analysis indicated that the ß-O-4' structure was largely destroyed, the G-type lignin dissolved early, and the degradation of the S-type lignin became more intensive with increasing reaction time. This is of great help for reaction control as well as the further processing of lignin byproducts.


Asunto(s)
Eucalyptus/química , Formiatos/farmacología , Lignina/aislamiento & purificación , Carbohidratos/aislamiento & purificación , Celulosa/análisis , Fraccionamiento Químico , Cromatografía Líquida de Alta Presión , Lignina/química , Estructura Molecular , Peso Molecular , Resonancia Magnética Nuclear Biomolecular , Solubilidad , Temperatura , Madera/química , Madera/efectos de los fármacos
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