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1.
For the sake of the quantitative method's applicability about wool, nylon, acrylic and polyester mixing fabrics in actual testing analyses, different methods were attempted to verify the results through the study on standard of FZ/T 01026-2009: Textiles-Quantitive chemical analysis-Quaternary fibre mixtures. The results indicated the existence of possible bias when chose the sequential solubility method A→B→C from the standard of FZ/T 01026-2009. However, the accurate experimental data and good reproducibility would be realized when adjust the program for A→B→D or B→A→D, and the result could be tested with distribution t.  相似文献   

2.
Multilayer films composed of PLA and agar/κ-carrageenan/clay (Cloisite® Na+) nanocomposite films were prepared, and the effect of lamination of PLA layers on the performance properties such as optical, mechanical, gas barrier, water resistance, and thermal stability properties was determined. The tensile strength (TS) of the agar/κ-carrageenan/clay nanocomposite films (67.8 ± 2.1 MPa) was greater than that of PLA films (43.3 ± 3.6 MPa), and the water vapor permeability (WVP), water uptake ratio (WUR), and water solubility (WS) of the nanocomposite films were higher than those of PLA films. The film properties of the multilayer films exhibited better properties of the component film layers. Especially, the WVP and water resistance of the bionanocomposite film were improved significantly, while the OTR of the PLA film decreased profoundly after lamination with PLA layers. Thermal stability of the bionanocomposite also increased after lamination with PLA layers.  相似文献   

3.
C. Anandharamakrishnan 《LWT》2008,41(2):270-277
A reversed phase HPLC technique has been applied to measure the loss of solubility (at pH 4.6) of α-lactalbumin and β-lactoglobulin resulting from the spray drying of whey protein isolate solution. Spray drying was performed in a pilot-scale co-current spray dryer with different feed concentrations (20-40% w/v) and outlet temperatures (60-120 °C). The study reveals that the solubility of both α-lactalbumin and β-lactoglobulin was not significantly affected at low outlet gas temperatures (60-80 °C), but was strongly affected (up to 40%) at high temperatures (100-120 °C). Significantly higher losses in solubility were observed for β-lactoglobulin compared to α-lactalbumin. Increasing the feed concentration at higher outlet temperatures also caused noticeable increases in insolubility. The reversed phase HPLC results were consistent with those from total protein nitrogen content (Kjeldhal) analyses.  相似文献   

4.
The microalgae, Spirulinaplatensis, is an excellent source of γ-linolenic acid (GLA), an essential polyunsaturated fatty acid and a potent nutraceutical. The fatty acid composition of S.platensis ARM 740 was determined after transmethylation by gas chromatography (GC). Lipid fractionation was achieved on silica gel column chromatography and preparative TLC. Neutral lipids, glycolipids and phospholipids accounted for 77.0%, 15.6% and 7.4%, respectively, of the total lipid fraction. S.platensis ARM 740 was found to contain 94% of the total GLA in the glycolipid fraction. Attempts were made to purify GLA methyl ester by using urea to form inclusion complexes with the saturated and the less unsaturated FAMEs (fatty acid methyl esters), which enhanced the purity of GLA methyl ester to 84%. A further approach to isolate GLA methyl ester with higher purity involved the use of argentated silica gel chromatography. An initial PUFA concentration step frequently adopted by most researchers to increase GLA purity was not necessary in the isolation of GLA from S.platensis. A GLA methyl ester with a purity of >96% and a recovery of 66% was obtained. Purity of the isolated GLA methyl ester was confirmed by GC and IR analysis with respect to authentic standard.  相似文献   

5.
6.
We investigated the molecular characteristics of 4-α-glucanotransferase (4αGTase)-modified rice starch (MRS) and corn starch (MCS) gels and the NaCl release properties depending on their mechanical properties. Also, encapsulation efficiency (EE) and oil globule size of water-in-oil-in-water (W/O/W) emulsions containing MRS or MCS in the inner aqueous phase (W1) with NaCl as a model core material were measured after preparation and 14 days of storage. The characteristics of MRS and MCS were examined by analyzing amylose content, molecular fine structure, microstructure, and mechanical properties to better understand their associations with emulsion stability. At 20 % concentration, the gel strength of MCS (~105 pa) was greater than that of MRS (~103 pa) as MCS had higher apparent amylose content than MRS. The rate of NaCl release from the gel was highly correlated with the gel strength that depended on the type and concentration of the enzymatically-modified starch. As the gel strength increased, EE of freshly prepared and stored W/O/W emulsions increased. Osmotic swelling of NaCl-containing W/O/W was significantly reduced with the incorporation of the modified starch gels in W1 phase. These results indicated that physicochemical properties of 4αGTase-modified starch gels in W/O/W emulsions largely affected the encapsulation efficiency and stability of the emulsions, which could be utilized to formulate W/O/W emulsions with improved stability and the potential for broader applications.  相似文献   

7.
The inclusion complex of trans-ferulic acid (FA) with hydroxypropyl-β-cyclodextrin (HP-β-CD) was prepared by the freeze-drying method and its characterisation was investigated by different analytical techniques including UV–visible spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray diffractometry, and scanning electron microscopy. All these approaches indicated that FA was able to form an inclusion complex with HP-β-CD, and the FA/HP-β-CD inclusion compounds exhibited different spectroscopic features and properties from FA. The stoichiometry of the complex was 1:1. The calculated apparent stability constant of the FA/HP-β-CD complex was 166.3 M−1, and the water solubility of FA was significantly improved by phase solubility studies. Moreover, the irradiation-induced decomposition of FA in aqueous solution was markedly reduced by complexation with HP-β-CD. The results showed that HP-β-CD was a proper excipient for increasing solubility and stability of FA.  相似文献   

8.
The aggregation state of (E)-resveratrol was studied in the presence and absence of hydroxypropyl-β-cyclodextrin (HP-β-CD) using absorption and steady-state fluorescence at different pH values. The results revealed that this potent antioxidant shows a monomer/aggregate equilibrium which is dependent on the protonation state of (E)-resveratrol. This equilibrium can be modified by the presence of HP-β-CD, which reduces the aggregation of the (E)-resveratrol molecules, producing individual molecules of the solute and preventing side effects due to aggregation phenomena. At pH values higher than the pKa1 of (E)-resveratrol, the coexistence of different protonated/deprotonated forms of this antioxidant does not permit the fluorimetric determination of the complexation constant (KF) of (E)-resveratrol with HP-β-CD. However, when the Hildebrand–Benesi equation was used to calculate this constant at physiological pH, this problem was resolved, with a KF value of 14490 ± 723 M−1 and the stoichiometry of the complexation process 1:1 for all the cases tested. The results obtained in this paper resolve the contradictory data published about the complexation process of (E)-resveratrol by cyclodextrins.  相似文献   

9.
Nanocellulose has served as an eye-catching nanomaterial for constructing advanced functional devices with renewability, light weight, flexibility, and environmental friendliness. In this study, Co3O4/graphene/cellulose nanofiber (CNF) flexible composite films, in which the CNF acted as a spacer for the graphene, were prepared via a facile and scalable vacuum filtration method. The effects of the CNF on the microstructure, hydrophilicity, thermal stability, tensile strength, surface resistance, and electrochemical performance of the Co3O4/graphene/CNF composite films were systematically investigated. The results showed that the synergistic interaction of the CNF and graphene substantially improved the overall properties of the Co3O4/graphene/CNF composite films, particularly their hydrophilicity and tensile strength. Meanwhile, Co3O4/graphene/CNF composite films with a CNF content of 4% appeared to have the optimal electrochemical performance, with an area specific capacitance of 56 mF/cm2 and prominent capacitance retention of 95.6% at a current density of 1 A/g after 1000 cycles. This work demonstrated that the prepared Co3O4/graphene/CNF flexible composite films have great application potential in the field of flexible energy storage devices.  相似文献   

10.
The present study was aimed to evaluate the impact of the co-culture on the output of malolactic fermentation and to further investigate the reasons of the antagonism exerted by yeasts towards bacteria during sequential cultures. The Saccharomyces cerevisiae D strain/Oenococcus oeni X strain combination was tested by applying both sequential culture and co-culture strategies. This pair was chosen amongst others because the malolactic fermentation was particularly difficult to realize during the sequential culture. During this traditional procedure, malolactic fermentation started when alcoholic fermentation was achieved. For the co-culture, both fermentations were conducted together by inoculating yeasts and bacteria into a membrane bioreactor at the same time. Results obtained during the sequential culture and compared to a bacterial control medium, showed that the inhibition exerted by S. cerevisiae D strain in term of decrease of the malic acid consumption rate was mainly due to ethanol (75%) and to a peptidic fraction (25%) having an MW between 5 and 10 kDa. 0.4 g l−1 of l-malic acid was consumed in this case while 3.7 g l−1 was consumed when the co-culture was applied. In addition, there was no risk of increased volatile acidity during the co-culture. Therefore, the co-culture strategy was considered effective for malolactic fermentation with the yeast/bacteria pair studied.  相似文献   

11.
Hydroxypropyl-β-cyclodextrin (HP-β-CD) is a β-cyclodextrin (β-CD) derivative which is toxicologically harmless to mammals and other animals. In this study, HP-β-CD is electrospun from an aqueous solution by blending with poly(ethylene oxide) (PEO). The aqueous solutions containing different HP-β-CD/PEO blends (50:50–90:10) with varying concentrations (4–12 wt.%) were electrospun at 1 ml/h feed rate, 12 cm working distance and 7 kV applied voltage. The morphology of the nanofibres was investigated by scanning electron microscope. The average diameter of the nanofibres was measured using ImageJ software. It was found from the results that the uniform nanofibres with an average diameter of 264, 244 and 236 nm were obtained from 8 wt.% solution of 50:50, 60:40 and 70:30 HP-β-CD/PEO blends, respectively. The average diameter of the fibre decreases with increasing HP-β-CD/PEO ratio. However, higher proportion of HP-β-CD (i.e. above 70:30 HP-β-CD/PEO blend) in the spinning solution increases the possibility of creating more beads in the fibres. Although the polymer concentrations have not shown a significant effect on fibre diameter, the 8 wt.% solution of 50:50 HP-β-CD/PEO yielded uniform smooth fibres with the narrowest distribution of the diameters. As the aim of this study is to maximize the HP-β-CD content in the fibre, the blend ratio of 70:30 HP-β-CD/PEO and solution concentration of 8 wt.% were optimized to obtain smooth HP-β-CD/PEO nanofibres.  相似文献   

12.
Summary The action of-irradiated patulin onSaccharomyces cerevisiae OCK 2144 in liquid culture was studied. Patulin irradiated in an aqueous solution with doses ranging over 0.34–1.36 kGy inhibited the yeast growth in a proportion to the concentration of undestroyed toxin. Patulin disappearance in the growth medium occurred between 12–72 h of incubation at 30° C. The patulin content did not essentially change in the period of log phase of yeast growth which is accompanied by rapid glucose uptake.
Einfluß des -bestrahlten Patulins aufSaccharomyces cerevisiae
Zusammenfassung Es wurde die Wirkung von-bestrahltem Patulin aufSaccharomyces cerevisiae OCK 2144 in Flüssigkultur untersucht. Patulin beeinflußte nach der Bestrahlung in wäßrigen Lösungen mit Dosen von 0,34 bis 1,36 kGy das Hefewachstum entsprechend dem Toxininhalt. Der Patulinabbau im Zuchtmedium erfolgte zwischen 12 und 72 h der Inkubation bei 30 °C. Der Patulingehalt veränderte sich nicht in der logarithmischen Phase des Hefewachstums, in dem der schnelle Glucoseverbrauch erfolgte.
  相似文献   

13.
We have evaluated the herb–drug interaction potential of Ssang-hwa-tang (SHT) mediated by cytochrome P450 (CYP) inhibition/induction. Further, the effects of fermentation on the CYP-mediated herb–drug interaction potential were determined. SHT showed inhibitory activity toward CYP1A2, but not 2A6, 2B6, 2C9, 2C19, 2D6, 2E1, and 3A4 in human liver microsomes. The results of the enzyme kinetic study suggested that the SHT-induced CYP1A2 inhibition is mixed reversible inhibition. The hepatic CYP expression and activity in rats treated with SHT were examined. The expression/activity of CYP2E1 increased as a result of SHT extract treatment (P < 0.005 or P < 0.001, respectively), which raises the possibility that SHT may increase the toxicity of environmental toxicants through the elevation of CYP2E1-mediated metabolic activation. SHT fermentation using Lactobacillus fermentum or Lactobacillus gasseri resulted in attenuation of the SHT-induced CYP1A2 inhibition, but not CYP2E1 induction, suggesting that changes in the chemical composition of SHT through fermentation can affect the inhibition of CYP1A2 activity.  相似文献   

14.
Response surface methodology (RSM) was applied to optimize the variables affecting the Supercritical carbon dioxide (SC–CO2) extraction of non-polar compounds from Zingiber zerumbet using the Box-Behnken design (BBD). Dependent variables were the percentage of the chemical components in the ginger vis a vis α-caryophyllene (y1), camphene (y2), and zerumbone (2,6,10-cycloundecatrien-1-one, 2,6,9,9-tetramethyl-) (y3). Pressure was the most significant parameter affecting the amount of each compound extracted. When temperature was kept constant and pressure was increased, all of the dependent variables increased concomitantly. Since pressure and temperature are two of the major influential factors in the extraction using SC–CO2, any combination of these two parameters could be selected to ascertain the optimum combination for a particular compound in the extract. Extraction at 30 °C and 55 MPa with total amount of 30 g of CO2 used was found to maximize all the responses.  相似文献   

15.
We determined the genetic background that would result in a more optimal display of heterologously expressed β-glucosidase (BGL) on the cell surface of yeast Saccharomyces cerevisiae. Amongst a collection of 28 strains carrying deletions in genes for glycosylphosphatidyl inositol (GPI)-anchored proteins, the Δsed1 and Δtos6 strains had significantly higher BGL-activity whilst maintaining wild type growth. Absence of Sed1p, which might facilitate incorporation of anchored BGL on the cell-surface, could also influence the activity of BGL on the cell surface with the heterologous gene being placed under the control of the SED1 promoter. For the evaluation of its industrial applicability we tested this system in heterologous and homogenous SED1-disruptants of sake yeast, a diploid S. cerevisiae strain, in which either the SED1 ORF or the complete gene including the promoter was deleted by use of the high-efficiency loss of heterozygosity method. Evaluation of disruptants displaying BGL showed that deletion of the SED1 ORF enhanced BGL activity on the cell surface, while additional deletion of the SED1 promoter increased further BGL activity on the cell surface. Compared to heterozygous disruption, homozygous disruption resulted generally in a higher BGL activity. Thus, homozygous deletion of both SED1 gene and promoter resulted in the most efficient display of BGL reaching a 1.6-fold increase of BGL-activity compared to wild type.  相似文献   

16.
《造纸信息》2013,(8):98-98
On April 9th, 2013, the project of energy conservation and emission reduction circulating fluidized bed boiler with an output of 100 t/h in Foshan Chengtong Paper Co., Ltd. officially put into trial operation.  相似文献   

17.
The study concerns the interactions between (+)-catechin and a representative oak wood aldehyde (5-(hydroxymethyl)furfuraldehyde for furanic aldehydes and vanillin for phenolic aldehydes) in a wine-like model solution in presence or not of SO2. The formed condensation products were characterised by LC/MS, LC/ESI/MSn, and ESI/HR/MS and we studied the effect of SO2 on these condensation reactions.  相似文献   

18.
This study presents hybrid clones of Corymbia spp. developed by Aperam BioEnergia as potential substitutes for Eucalyptus wood in the pulp industry. The biomass of Eucalyptus spp. was compared with that of Corymbia spp. by performing modified kraft pulping and basic density analyses. Comparisons were made by analyzing their respective mean annual increments of cellulose (MAIcel) and specific wood consumption (SWC), estimated using a kappa number of (19 ± 1). The results showed that one of the hybrid clones (Corymbia citriodora × Corymbia torelliana, ID 4) had higher basic wood density, higher screened yield, better MAIcel#k19, and lower SWC than the other samples, reaching values of 0.608 t/m3, 54.1%, 24.6 ADt/ha/year (i.e., air dry ton/hectare/year), and 2.74 m3/ADt, respectively. Consequently, clone ID 4 had the highest MAIcel/SWC ratio score (8.98). Given its high forest productivity and low industrial cost compared with other samples, as well as its advantages over Eucalyptus spp. wood, we concluded that clone ID 4 has great potential as an alternative biomass for pulp production.  相似文献   

19.
α-Galactosidase or melibiase is a versatile enzyme with many potential biotechnological and industrial applications. The substrate specificities of three α-galactosidases – α-Gal I, α-Gal II, and α-Gal III – from Streptomyces griseoloalbus were studied using different galactose-containing natural substrates like melibiose, raffinose and stachyose. The kinetic parameters Km and Vmax were determined from the Lineweaver–Burk plot. α-Gal I showed highest affinity towards melibiose where as α-Gal II and α-Gal III showed highest affinity towards stachyose. The 1H NMR studies showed that all the three α-galactosidases had a retaining mechanism of hydrolysis.  相似文献   

20.
It is recognised that inoculum size affects the rate and extent of bacterial spore germination. It has been proposed that this is due to spores interacting: molecules released from germinated spores trigger germination of dormant neighbours. This study investigated whether changes to the total number of spores in a system or proximity to other spores (local spore density) had a more significant effect on interaction between spores of non-proteolytic Clostridium botulinum strain Eklund 17B attached to defined areas of microscope slides. Both the number of spores attached to the slides and local spore density (number of spores per mm2) were varied by a factor of nine. Germination was observed microscopically at 15 °C for 8 h and the probability of, and time to, germination calculated from image analysis measurements. Statistical analysis revealed that the effect of total spore number on the probability of germination within 8 h was more significant than that of proximity to neighbours (local spore density); its influence on germination probability was approximately four-times greater. Total spore number had an even more significant affect on time to germination; it had a nine-fold greater influence than proximity to neighbours. The applied models provide a means to characterise, quantitatively, the effect of the total spore number on spore germination relative to the effect of proximity to neighbouring spores.  相似文献   

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