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41.
42.
1. Japanese quail were fed on practical diets supplemented with graded amounts of DL-methionine (DL-M), DL-methionine-sodium (DL-M-Na), DL-methionine hydroxy-analogue calcium (DL-MHA-Ca) and DL-methionine hydroxy-analogue free acid (DL-MHA-FA) on an equimolar basis. 2. By the slope ratio assay using quail growth as the criterion, it was deduced that the biological activity of DL-M-Na, DL-MHA-Ca and DL-MHA-FA was approximately 0.96, 0.72 and 0.84 that of DL-M on an equimolar basis. 3. On a weight basis of the commercial products, the efficacies of DL-M-Na, DL-MHA-Ca and DL-MHA-FA were 0.38, 0.62 and 0.74, respectively. 4. Quail fed on the diet with the highest content of methionine had greater ovary weight, oviduct weight, oviduct length and egg production.  相似文献   
43.
High-harmonic generation (HHG) traditionally combines ~100 near-infrared laser photons to generate bright, phase-matched, extreme ultraviolet beams when the emission from many atoms adds constructively. Here, we show that by guiding a mid-infrared femtosecond laser in a high-pressure gas, ultrahigh harmonics can be generated, up to orders greater than 5000, that emerge as a bright supercontinuum that spans the entire electromagnetic spectrum from the ultraviolet to more than 1.6 kilo-electron volts, allowing, in principle, the generation of pulses as short as 2.5 attoseconds. The multiatmosphere gas pressures required for bright, phase-matched emission also support laser beam self-confinement, further enhancing the x-ray yield. Finally, the x-ray beam exhibits high spatial coherence, even though at high gas density the recolliding electrons responsible for HHG encounter other atoms during the emission process.  相似文献   
44.
Novel regenerated cellulose material which was prepared from cellulose acetate fiber through the hydrolysis of acetyl groups have been developed by an environmentally friendly process without emitting toxic substances in addition to be at low production cost. They have composite crystalline structure constituted of cellulose II and cellulose IV. Also, they show a lamellar morphology with an increased amorphous region, as compared to conventional regenerated cellulose such as viscose rayon and cupra rayon. Our data obtained by several independent methods demonstrated that the adsorption properties of cellulose fibers depend predominantly on the amorphous region.  相似文献   
45.
This study evaluated the extraction of two colors of dye (yellow and brown) from Coreopsis tinctoria flower petals using ultrasound and the dyeing of leather with the extracted dyes as a source of nontoxic and eco-friendly dye. The results showed an increase in the dye extraction values with increasing time at 100 W ultrasonic power at 80 °C for 1 h. Leather dyeing was optimized with the aid of ultrasound and magnetic stirring. The optimum leather dyeing conditions, with respect to the dye uptake, dye penetration and intensity of the color, were determined to be 12 % dye concentration, 100 W power, 1,000 rpm, and pH 7.0 for 60 min at 80 °C. It was shown that sonication improves dye exhaustion from a 90 % to 60 % rating for 1 h of dyeing time. The dyed leather was assessed by reflectance measurements and compared with visual assessment data. The fastness properties of dyed leather samples showed good fastness against washing, light, and dry and wet rubbing. The strength properties were not significantly altered and the bulk properties, such as softness, were found to be improved by the use of Coreopsis tinctoria yellow and brown dyes using an ultrasonic and magnetic stirring dyeing process.  相似文献   
46.
Evaluation of the dyeability of the new eco-friendly regenerated cellulose   总被引:1,自引:0,他引:1  
Three commercial dyes-direct, reactive, and vat dye-were applied to the new regenerated cellulose fiber which was prepared from cellulose acetate fiber through the hydrolysis of acetyl groups with an environmentally friendly manufacturing process. The effect of salt, alkali, liquor ratio, temperature, and leveling agent on the dyeing behavior and fastness were evaluated and compared with regular viscose rayon. From the results, we found that new regenerated cellulose fiber exhibited better dyeability and fastness than regular viscose rayon.  相似文献   
47.
Acupoints on the Large Intestine Meridian and specific acupoints related with large intestine have been empirically used to treat large intestinal disease. However, the relationship between acupoints related with large intestine and their functions has not been investigated fully. We investigated whether large intestine-related acupoints affect colonic motility in conscious dogs implanted with electrodes at the proximal colon. Manual acupuncture was applied at the following acupoints: 7 main points on the Large Intestine Meridian (LI1, LI2, LI3, LI4, LI5, LI6, and LI11), ST25, BL25 or GV1. Acupuncture at the Large Intestine Meridian acupoints, ST25 and BL25 had no significant effects on the proximal colonic motility. However, acupuncture at GV1 depressed the proximal colonic motility by decreasing the total duration and the frequency of contractile states, which may contribute to the therapeutic effects of GV1. This study also revealed that there was no clear correlation between Large Intestine Meridian and the proximal colonic motility in conscious dogs.  相似文献   
48.
A sensitive and specific assay was developed to detect potato blackleg caused by Pectobacterium atrosepticum in potato. Primers PEAF and PEAR from the Rhs family gene homologous to RhsA (cell envelope biogenesis – outer membrane) were used to amplify a 904 bp DNA fragment. PCR was used to detect the pathogen in artificially inoculated potato seed tubers. The PCR product was only produced from 12 isolates of P. atrosepticum from various countries among 36 isolates of other species of Pectobacterium , Pseudomonas , Xanthomonas , as well as Escherichia coli and the soilborne fungus Fusarium oxysporum f.sp. dianthi .  相似文献   
49.
Laboratory studies on the formation of bound residues and on the degradation of the triazole fungicide propiconazole were conducted in two different soils. Soils treated with 14C-propiconazole were incubated at 22 degrees C and extracted exhaustively with a solvent at each sampling date until no further propiconazole was extracted. The solvent-extractable residues were used to measure propiconazole remaining in the soil, and the extracted soils were used to investigate bound residues of propiconazole. Mineralization of propiconazole was investigated by measuring [14C]carbon dioxide evolved from the soil samples. Formation of bound residues of propiconazole was higher in silty clay loam soil than in sandy loam soil, giving approximately 38 and 23% of the applied 14C, respectively. In contrast, the rates of degradation and mineralization of propiconazole were lower in silty clay loam soil than in sandy loam soil. Decreased extractability of the 14C residues with incubation time was observed with increased formation of bound residues. When the propiconazole remaining in the solvent-extractable residues was quantitatively measured by high-pressure liquid chromatographic analysis, the half-life value in sandy loam soil was about 315 days, while the half-life in silty clay loam soil exceeded the duration of the 1 year experimental period. Increased formation of bound residues was observed as propiconazole degraded with incubation time, suggesting that degradation products are involved in the formation of bound residues. Our study suggests that the formation of bound residues of propiconazole contributes to the persistence of this fungicide in soil.  相似文献   
50.
Mixtures of t,t conjugated linoleic acid methylester (t,t CLA-Me) isomers were prepared from synthetic CLA, consisting of 47.8% t10,c12 CLA; 45.5% c9,t11 CLA; 2.0% t,t CLA; and 4.7% others, by methylation with BF(3)/methanol (designated TT-TC/CT) in conjunction with purification at -68 degrees C for 24 h. The amount or composition of the TT-TC/CT was greatly affected by the concentration of BF(3) in methanol and the duration of methylation. The methylation of 50 mg of synthetic CLA for 30 min with 1 mL of 7.0% BF(3)/methanol produced a TT-TC/CT (21.54 mg) with the composition of 1.3% t12,t14; 5.9% t11,t13; 42.7% t10,t12; 44.0% t9,t11; 5.0% t8,t10; and 1.1% t 7,t9 CLA, whereas the methylation for 60 min with 14.0% BF(3)/methanol produced a TT-TC/CT (28.62 mg) with the composition of t,t CLA isomers different from that of TT-TC/CT by methylation for 30 min with 7.0% BF(3)/methanol. A large quantity of TT-TC/CT (14.15 g) with the composition similar to that of TT-TC/CT prepared from 50 mg of synthetic CLA was also prepared from 25 g of synthetic CLA. The purity of TT-TC/CT samples was greater than 98%. These results suggest that TT-TC/CT with a purity greater than 98% was easily prepared from synthetic CLA by BF(3)-catalyzed methylation, and the amount and composition of t,t CLA isomers of TT-TC/CT samples could be controlled by methylation conditions.  相似文献   
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