A new bacterial strain,was designated as strain Acidiphilium cryptum DX1-1,accumulates intracellular poly-β-hydroxybutyrate particles,four methods which have advantages and disadvantages for each were employed to ext...A new bacterial strain,was designated as strain Acidiphilium cryptum DX1-1,accumulates intracellular poly-β-hydroxybutyrate particles,four methods which have advantages and disadvantages for each were employed to extract PHB.Chloroform-sodium hypochlorite method is the best in extracting PHB form Acidiphilium cryptum DX1-1.The extraction rate reaches 73%,the purification rate is 92% and molecular weight is 326 kg/mol.Then the PHB extracted by this method was analyzed by ultraviolet-visible absorption spectroscopy,fourier transform infrared(FT-IR) and nuclear magnetic resonance(NMR).The results show that PHB from strain DX1-1 has the same biochemical structure and character with PHB standard.Mass spectrometer(MS) analysis reveals that the long chain of PHB is destroyed when treated by chloroform-sodium hypochlorite.The differential scanning calorimetry(DSC) of PHB shows PHB from Acidiphilium cryptum DX1-1 has low degree of crystallinity which makes the PHB has a wider range of applications.展开更多
In order to characterize the organic properties of waste activated sludge in a wastewater treatment plant,organic matter within sludge was extracted with NH 3 ·H 2 O preferentially,and subsequently fractionated i...In order to characterize the organic properties of waste activated sludge in a wastewater treatment plant,organic matter within sludge was extracted with NH 3 ·H 2 O preferentially,and subsequently fractionated into five fractions using XAD-8/XAD-4 resins.Up to a 63.8%-71.1% of organic matter within the sludge could be efficiently extracted by NH 3 ·H 2 O.Fractionation results showed that hydrophobic acid and hydrophilic fraction were two main components among the sludge organic matter (accounting for 32.2% and 48.0% of the bulk organic matter,respectively),whereas transphilic acid,hydrophobic neutral and transphilic neutral were quite low (accounting for 9.2%,5.8% and 4.8%,respectively).Despite that the extractant of NH 3 ·H 2 O showed a relatively higher extraction efficiency of the aromatic components,the relatively low aromaticity of the organic fractions implied that those non-aromatic components could also be effectively extracted,especially for neutral and hydrophilic fractions.In addition,acidic fractions contained more aromatic humic-like components,whereas the neutral fractions had a greater content of aromatic proteins and soluble microbial byproduct-like components.Extraction of sludge organics with NH3·H2O and subsequential fractionation using XAD resins could be a novel method for further characterization of sludge organics.展开更多
In Africa, traditional vegetable oil extraction often involves the use of plants in the manufacturing process. <span style="font-family:Verdana;"><span style="font-family:Verdana;"><...In Africa, traditional vegetable oil extraction often involves the use of plants in the manufacturing process. <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Quassia undulate</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil is thus traditionally prepared. An expedition went to Kédougo (a region in southeastern Senegal involving women of the Bassaris community) in June 2018 to study the </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Q</span></i></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">.</span><i><span style="font-family:Verdana;"> undulate</span></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil traditional extraction mode. Thus, the objective of this study is to follow the traditional extraction of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Q</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><i><span style="font-family:;" "=""> </span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">undulate</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil and to perform the physico-chemical analysis of the obtained oil. Oil samples taken after the survey allowed the oil physico-chemical characterization. The traditional oil extraction made by four women from Eganga, Ethiolo, and Ebarack’s villages reveals oil clear that is solid at room temperature. The study of the established chart revealed the use of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Pilliostigma</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> <i>thonnintigi</i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> leaves during the oil preparation. The oil shows characteristics comparable to shea butter, and the oil stability can be compared to the corn and peanut oil one. The physicochemical analysis showed oil solid at room temperature with an acid value between </span><span style="font-family:Verdana;">1.223 ± 0.013 and 7.333 ± 0.465. The saponification value was between</span><span style="font-family:Verdana;"> 190.489 ± 3.083 and 199.732 ± 3.107, and the peroxide value between 4.453 ± 0.042 and 8.644 ± 0.285. The iodine value</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> were between 21.455 ± 2.440 and 38.068 ± 0.082, and the refractive index 1.462 - 1.463. </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Q</span></i></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">.</span><i><span style="font-family:Verdana;"> undulate</span></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil offers several technological perspectives. However, it would be interesting to study the impact of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">P</span></i></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">.</span><i><span style="font-family:Verdana;"> thonnintigi</span></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> leaves during extraction. The fatty acid profile should also be determined.</span></span></span>展开更多
The paper reported a comparative study of the methods of extraction of <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;&qu...The paper reported a comparative study of the methods of extraction of <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">vegetable fibres encountered in the literature;three main ones was chose, namely: combing, retting with pre-treatment of the bagasse in salt and distilled water,</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">and Chemical extraction at three concentration levels of soda (2N, 1N, 0.1N) </span><span style="font-family:Verdana;">with pre-treatment of bagasse with salt water and distilled water. After extracting the fibres using these methods, it appeared that the natural methods (retting and combing) have a higher yield of around 70% compared to the</span><span style="font-family:Verdana;"> chemical method which has a low yield of around 40%. The fibres obtained by the chemical extraction method (1N-BPD) had the best characteristics</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span>展开更多
Baizhi, as a medicinal plant, has been demonstrated to be useful for the treatment of aches and pains in China. The physicochemical characterization of Baizhi particles is greatly influenced by ultrafine pulverization...Baizhi, as a medicinal plant, has been demonstrated to be useful for the treatment of aches and pains in China. The physicochemical characterization of Baizhi particles is greatly influenced by ultrafine pulverization. To study the physicochemical characterization of Baizhi, the raw plant material of Baizhi was ground to 6 μm particles by a high speed centrifugal sheering (HSCS) pulverizer. The micron particles were characterized by optical microscopy and scanning electron microscopy (SEM). Imperatorin is one of the active ingredients of Baizhi, and its extraction yield is determined to evaluate the chemical characterization of Baizhi powder. Imperatorin was analyzed by high performance liquid chromatography (HPLC). The results show that after ultrafine pulverization, the plant cell walls are broken into pieces and the extraction yield of imperatorin is increased by 11.93% compared with the normal particles.展开更多
Extraction of dye from dry fruit of Rothmannia whitfieldii was carried out using four different extraction methods. Solvent and acid extraction methods gave a colourless supernatant solution after extraction time of 4...Extraction of dye from dry fruit of Rothmannia whitfieldii was carried out using four different extraction methods. Solvent and acid extraction methods gave a colourless supernatant solution after extraction time of 45 minutes at 60°C. The alkali method gave a deep brown coloured supernatant solution while the aqueous method gave a dark coloured supernatant solution after extraction under the same conditions. From the result of the FTIR spectroscopy characterization of the coloured solutions and the dry powder of Rothmannia whitfieldii fruit, it was observed that only the alkali method extracted what can be called a dye with likely presence of tannins. The result also showed that the possible functional groups present in the supernatant solution after aqueous extraction are same with the functional groups present in the dry pulverized Rothmannia whitfieldii fruit. Hence, aqueous method did not extract any dye. Similarly, a mixture of the solution after aqueous extraction with drops of alkali solution produced a deep brown coloured solution indicating solubility of the dye component in alkali media.展开更多
The aqueous extract of Phellodendron amurense Rupr. (Amur Cork Tree) provides a rich source of antioxidants and chemical compounds, and can be used for food and wood preservative materials. In this study, we charact...The aqueous extract of Phellodendron amurense Rupr. (Amur Cork Tree) provides a rich source of antioxidants and chemical compounds, and can be used for food and wood preservative materials. In this study, we characterized the chemical composition of this extract by GC and GC/MS. The antioxidant capacity was evaluated using a variety of antioxidant assays (superoxide radical, hydroxyl radical, nitric oxide radical, and DPPH radical scavenging activity). Additionally, total polyphenolic content was determined. Phenolic acids and acetone derivatives were major compounds of the extract capable of scavenging the DPPH free radical and reducing ferric ions. DPPH and ferric ion reduction results were strongly correlated with total phenolic content of the extract which also exhibited strong nitric oxide, hydroxyl radical scavenging and superoxide anion radical scavenging activities.展开更多
Organic-dispersible lanthanide fluorides nanocrystals were synthesized at a large scale using colloid-extraction method, in the presence of dialkyl-dithiophosphinic acid (DDPA) as the extraction agent. The products we...Organic-dispersible lanthanide fluorides nanocrystals were synthesized at a large scale using colloid-extraction method, in the presence of dialkyl-dithiophosphinic acid (DDPA) as the extraction agent. The products were characterized by means of X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier transformation infrared (FTIR) spectroscopy. It was found that the synthesized lanthanide fluorides nanoparticles had high purity and crystallinity, and could be well dispersed in organic solvents such as chloroform, toluene etc., which could be closely related to the surface-capping of the nanocrystals by the DDPA molecules. Moreover, the nanocrystals before and after extraction by DDPA showed few differences in the microscopic morphologies. It was implied that DDPA as the extraction agent had good protection to the nanocrystals as well, which could be essential to the commercial application of the titled rare earth nanocrystals as novel multifunctional additives in the fields of lubrication.展开更多
In this paper, a kind of three-dimensional analysis technology for characterizing non-metallic inclusions in steel was clearly elaborated. It is an electron microscopy observation, namely the non-aqueous electrolysis ...In this paper, a kind of three-dimensional analysis technology for characterizing non-metallic inclusions in steel was clearly elaborated. It is an electron microscopy observation, namely the non-aqueous electrolysis extraction method with a settled coulometer. In the research,the extraction effects of non-metallic inclusions in different electrolysis systems were studied, and it was concluded that alkalescent 2% TEA non-aqueous electrolyte was applicable for extracting most of non-metallic inclusion particles in steel. And then, in order to ensure the microscopic characterization and statistical calculation of inclusion particles, some electrolysis parameters should be confirmed, such as the size of the sample, control of the electrolysis mass, electric current, etc. Furthermore, for preventing the disturbance of carbides and presenting clear three-dimensional appearance by microscopic characterization, magnetic separation was utilized to separate the inclusion particles from carbides, which was useful for getting more veracious types, particle sizes and chemical composition of inclusions. Moreover, through calculation of quantity and particle size of inclusions in continuous determinate fields, the total quantity per unit volume or area and the particle size distribution of inclusions could be acquired by conversion with electrolysis loss. Besides, the comparison between this method and traditional quantitative metallography was also discussed, and finally, a conclusion was drawn that both of them have respectively applications in characterizing inclusions.展开更多
The process of oxidation, due to free radicals, is the cause of major concern for human health. In particular damages related to the skin have great relevance;therefore, many antioxidants based products are developed ...The process of oxidation, due to free radicals, is the cause of major concern for human health. In particular damages related to the skin have great relevance;therefore, many antioxidants based products are developed and marketed with the intention to counteract the action of free radicals. The seed of Araucaria angustifolia is a rich source of antioxidants due to the presence of bioflavonoids to counteract free radicals damages. In this study, two extracts, one from the seed external teguments (shell) and the other from the inner seed pulp (endosperm and embryo) were obtained in order to evaluate possible applications to the dermo-cosmetic field. In parallel the following different methods were employed to characterize both the extracts and to determine their antioxidant capacity: HPTLC, ABTS and DPPH, ORAC and PLC. The qualitative analysis showed that both extracts have the antioxidant activity, but the quantitative evaluation revealed a more promising bioactivity from the shell than from the pulp. Therefore, it was evaluated the potential skin application of different cosmetic formulations, based on the presence of seed shell extract (W/O emulsion, O/W emulsion and gel). The best result was achieved with the W/O emulsion.展开更多
基金Funded by the National Natural Science Foundation for Distinguished Group (No. 50621063)the National Natural Science Foundation of China (No.50674101)the National Innovation Experiment Program for University Students (No. 81053321)
文摘A new bacterial strain,was designated as strain Acidiphilium cryptum DX1-1,accumulates intracellular poly-β-hydroxybutyrate particles,four methods which have advantages and disadvantages for each were employed to extract PHB.Chloroform-sodium hypochlorite method is the best in extracting PHB form Acidiphilium cryptum DX1-1.The extraction rate reaches 73%,the purification rate is 92% and molecular weight is 326 kg/mol.Then the PHB extracted by this method was analyzed by ultraviolet-visible absorption spectroscopy,fourier transform infrared(FT-IR) and nuclear magnetic resonance(NMR).The results show that PHB from strain DX1-1 has the same biochemical structure and character with PHB standard.Mass spectrometer(MS) analysis reveals that the long chain of PHB is destroyed when treated by chloroform-sodium hypochlorite.The differential scanning calorimetry(DSC) of PHB shows PHB from Acidiphilium cryptum DX1-1 has low degree of crystallinity which makes the PHB has a wider range of applications.
基金supported by the National Nature Science Foundation of China (National Creative Research Groups) (No. 50821002)the State Key Laboratory of Urban Water Resource and Environment,Harbin Instituteof Technology (No. 2008DX05)+2 种基金the Key Projects in the National Science and Technology Pillar Program during the Eleventh Five-year Plan Period (No. 2006BAC19B04)the Heilongjiang Province Science Foundation for Youths(No. QC2009C113/E0804)the Shanghai Tongji GaoTingyao Environmental Science & Technology Development Foundation
文摘In order to characterize the organic properties of waste activated sludge in a wastewater treatment plant,organic matter within sludge was extracted with NH 3 ·H 2 O preferentially,and subsequently fractionated into five fractions using XAD-8/XAD-4 resins.Up to a 63.8%-71.1% of organic matter within the sludge could be efficiently extracted by NH 3 ·H 2 O.Fractionation results showed that hydrophobic acid and hydrophilic fraction were two main components among the sludge organic matter (accounting for 32.2% and 48.0% of the bulk organic matter,respectively),whereas transphilic acid,hydrophobic neutral and transphilic neutral were quite low (accounting for 9.2%,5.8% and 4.8%,respectively).Despite that the extractant of NH 3 ·H 2 O showed a relatively higher extraction efficiency of the aromatic components,the relatively low aromaticity of the organic fractions implied that those non-aromatic components could also be effectively extracted,especially for neutral and hydrophilic fractions.In addition,acidic fractions contained more aromatic humic-like components,whereas the neutral fractions had a greater content of aromatic proteins and soluble microbial byproduct-like components.Extraction of sludge organics with NH3·H2O and subsequential fractionation using XAD resins could be a novel method for further characterization of sludge organics.
文摘In Africa, traditional vegetable oil extraction often involves the use of plants in the manufacturing process. <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Quassia undulate</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil is thus traditionally prepared. An expedition went to Kédougo (a region in southeastern Senegal involving women of the Bassaris community) in June 2018 to study the </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Q</span></i></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">.</span><i><span style="font-family:Verdana;"> undulate</span></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil traditional extraction mode. Thus, the objective of this study is to follow the traditional extraction of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Q</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><i><span style="font-family:;" "=""> </span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">undulate</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil and to perform the physico-chemical analysis of the obtained oil. Oil samples taken after the survey allowed the oil physico-chemical characterization. The traditional oil extraction made by four women from Eganga, Ethiolo, and Ebarack’s villages reveals oil clear that is solid at room temperature. The study of the established chart revealed the use of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Pilliostigma</span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> <i>thonnintigi</i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> leaves during the oil preparation. The oil shows characteristics comparable to shea butter, and the oil stability can be compared to the corn and peanut oil one. The physicochemical analysis showed oil solid at room temperature with an acid value between </span><span style="font-family:Verdana;">1.223 ± 0.013 and 7.333 ± 0.465. The saponification value was between</span><span style="font-family:Verdana;"> 190.489 ± 3.083 and 199.732 ± 3.107, and the peroxide value between 4.453 ± 0.042 and 8.644 ± 0.285. The iodine value</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> were between 21.455 ± 2.440 and 38.068 ± 0.082, and the refractive index 1.462 - 1.463. </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">Q</span></i></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">.</span><i><span style="font-family:Verdana;"> undulate</span></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> oil offers several technological perspectives. However, it would be interesting to study the impact of </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i></i></span></span></span><i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">P</span></i></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">.</span><i><span style="font-family:Verdana;"> thonnintigi</span></i></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;"></span></i></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> leaves during extraction. The fatty acid profile should also be determined.</span></span></span>
文摘The paper reported a comparative study of the methods of extraction of <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">vegetable fibres encountered in the literature;three main ones was chose, namely: combing, retting with pre-treatment of the bagasse in salt and distilled water,</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">and Chemical extraction at three concentration levels of soda (2N, 1N, 0.1N) </span><span style="font-family:Verdana;">with pre-treatment of bagasse with salt water and distilled water. After extracting the fibres using these methods, it appeared that the natural methods (retting and combing) have a higher yield of around 70% compared to the</span><span style="font-family:Verdana;"> chemical method which has a low yield of around 40%. The fibres obtained by the chemical extraction method (1N-BPD) had the best characteristics</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span>
基金supported by the National High-Tech Research and Development Program of China (No.2009AA043202)the Special Project of State Administration of Traditional Chinese Medicine, China (No.200807054)
文摘Baizhi, as a medicinal plant, has been demonstrated to be useful for the treatment of aches and pains in China. The physicochemical characterization of Baizhi particles is greatly influenced by ultrafine pulverization. To study the physicochemical characterization of Baizhi, the raw plant material of Baizhi was ground to 6 μm particles by a high speed centrifugal sheering (HSCS) pulverizer. The micron particles were characterized by optical microscopy and scanning electron microscopy (SEM). Imperatorin is one of the active ingredients of Baizhi, and its extraction yield is determined to evaluate the chemical characterization of Baizhi powder. Imperatorin was analyzed by high performance liquid chromatography (HPLC). The results show that after ultrafine pulverization, the plant cell walls are broken into pieces and the extraction yield of imperatorin is increased by 11.93% compared with the normal particles.
文摘Extraction of dye from dry fruit of Rothmannia whitfieldii was carried out using four different extraction methods. Solvent and acid extraction methods gave a colourless supernatant solution after extraction time of 45 minutes at 60°C. The alkali method gave a deep brown coloured supernatant solution while the aqueous method gave a dark coloured supernatant solution after extraction under the same conditions. From the result of the FTIR spectroscopy characterization of the coloured solutions and the dry powder of Rothmannia whitfieldii fruit, it was observed that only the alkali method extracted what can be called a dye with likely presence of tannins. The result also showed that the possible functional groups present in the supernatant solution after aqueous extraction are same with the functional groups present in the dry pulverized Rothmannia whitfieldii fruit. Hence, aqueous method did not extract any dye. Similarly, a mixture of the solution after aqueous extraction with drops of alkali solution produced a deep brown coloured solution indicating solubility of the dye component in alkali media.
文摘The aqueous extract of Phellodendron amurense Rupr. (Amur Cork Tree) provides a rich source of antioxidants and chemical compounds, and can be used for food and wood preservative materials. In this study, we characterized the chemical composition of this extract by GC and GC/MS. The antioxidant capacity was evaluated using a variety of antioxidant assays (superoxide radical, hydroxyl radical, nitric oxide radical, and DPPH radical scavenging activity). Additionally, total polyphenolic content was determined. Phenolic acids and acetone derivatives were major compounds of the extract capable of scavenging the DPPH free radical and reducing ferric ions. DPPH and ferric ion reduction results were strongly correlated with total phenolic content of the extract which also exhibited strong nitric oxide, hydroxyl radical scavenging and superoxide anion radical scavenging activities.
基金Project supported bythe National Natural Science Foundation of China (20401006)Natural Science Foundation of Henan Province (200510475019)
文摘Organic-dispersible lanthanide fluorides nanocrystals were synthesized at a large scale using colloid-extraction method, in the presence of dialkyl-dithiophosphinic acid (DDPA) as the extraction agent. The products were characterized by means of X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier transformation infrared (FTIR) spectroscopy. It was found that the synthesized lanthanide fluorides nanoparticles had high purity and crystallinity, and could be well dispersed in organic solvents such as chloroform, toluene etc., which could be closely related to the surface-capping of the nanocrystals by the DDPA molecules. Moreover, the nanocrystals before and after extraction by DDPA showed few differences in the microscopic morphologies. It was implied that DDPA as the extraction agent had good protection to the nanocrystals as well, which could be essential to the commercial application of the titled rare earth nanocrystals as novel multifunctional additives in the fields of lubrication.
文摘In this paper, a kind of three-dimensional analysis technology for characterizing non-metallic inclusions in steel was clearly elaborated. It is an electron microscopy observation, namely the non-aqueous electrolysis extraction method with a settled coulometer. In the research,the extraction effects of non-metallic inclusions in different electrolysis systems were studied, and it was concluded that alkalescent 2% TEA non-aqueous electrolyte was applicable for extracting most of non-metallic inclusion particles in steel. And then, in order to ensure the microscopic characterization and statistical calculation of inclusion particles, some electrolysis parameters should be confirmed, such as the size of the sample, control of the electrolysis mass, electric current, etc. Furthermore, for preventing the disturbance of carbides and presenting clear three-dimensional appearance by microscopic characterization, magnetic separation was utilized to separate the inclusion particles from carbides, which was useful for getting more veracious types, particle sizes and chemical composition of inclusions. Moreover, through calculation of quantity and particle size of inclusions in continuous determinate fields, the total quantity per unit volume or area and the particle size distribution of inclusions could be acquired by conversion with electrolysis loss. Besides, the comparison between this method and traditional quantitative metallography was also discussed, and finally, a conclusion was drawn that both of them have respectively applications in characterizing inclusions.
文摘The process of oxidation, due to free radicals, is the cause of major concern for human health. In particular damages related to the skin have great relevance;therefore, many antioxidants based products are developed and marketed with the intention to counteract the action of free radicals. The seed of Araucaria angustifolia is a rich source of antioxidants due to the presence of bioflavonoids to counteract free radicals damages. In this study, two extracts, one from the seed external teguments (shell) and the other from the inner seed pulp (endosperm and embryo) were obtained in order to evaluate possible applications to the dermo-cosmetic field. In parallel the following different methods were employed to characterize both the extracts and to determine their antioxidant capacity: HPTLC, ABTS and DPPH, ORAC and PLC. The qualitative analysis showed that both extracts have the antioxidant activity, but the quantitative evaluation revealed a more promising bioactivity from the shell than from the pulp. Therefore, it was evaluated the potential skin application of different cosmetic formulations, based on the presence of seed shell extract (W/O emulsion, O/W emulsion and gel). The best result was achieved with the W/O emulsion.