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41.
Gas adsorption sites in a large-pore metal-organic framework 总被引:2,自引:0,他引:2
Rowsell JL Spencer EC Eckert J Howard JA Yaghi OM 《Science (New York, N.Y.)》2005,309(5739):1350-1354
The primary adsorption sites for Ar and N2 within metal-organic framework-5, a cubic structure composed of Zn4O(CO2)6 units and phenylene links defining large pores 12 and 15 angstroms in diameter, have been identified by single-crystal x-ray diffraction. Refinement of data collected between 293 and 30 kelvin revealed a total of eight symmetry-independent adsorption sites. Five of these are sites on the zinc oxide unit and the organic link; the remaining three sites form a second layer in the pores. The structural integrity and high symmetry of the framework are retained throughout, with negligible changes resulting from gas adsorption. 相似文献
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43.
H. Bergmann H. Eckert C. Weber und D. Roth 《Journal of Agronomy and Crop Science》1991,166(2):117-126
Effect of monoethanolamine on yield of crops
I. Studies on the effect of monoethanolamine on the grain yield and the nitrogen household in cereal plants (pot experiments)
The effect of monoethanolamine (EA, applied as foliar spray, 10 mg per pot) on grain yield and yield components was investigated in pot experiments with spring barley, winter wheat, and winter rye. Under conditions of a moderate drought stress the applied EA increased the grain yield of spring barley from 5 % to 7 % (significance only at α= 0.05). A stimulating effect of EA on the grain yield of winter wheat and winter rye was also obtained.
The positive influence of EA on the grain yield of spring barley was reproducible under the conditions of a limited water supply in small-scale plot experiments (increase of yield about 9 %).
In case of spring barley and winter rye the increase of the grain yield by EA, applied at growth stage 31 (= DC 31) was connected with a greater number of ear-bearing tillers. The increase of the winter wheat yield resulted from more grains per ear of the tillers.
The enhanced formation of tiller grain mass and total tiller biomass by EA was in correlation with a higher nitrogen import into tillers (r = 0.8+ ). Since an export of N from the main shoots into the tillers was not observed a higher N uptake (≥ 6 %) was calculated from N balances. After a fertilization with 15 N-labelled fertilizers the additional 15 N uptake was 13 % to 20 %.
Possible stress reducing activities caused by EA are discussed. 相似文献
I. Studies on the effect of monoethanolamine on the grain yield and the nitrogen household in cereal plants (pot experiments)
The effect of monoethanolamine (EA, applied as foliar spray, 10 mg per pot) on grain yield and yield components was investigated in pot experiments with spring barley, winter wheat, and winter rye. Under conditions of a moderate drought stress the applied EA increased the grain yield of spring barley from 5 % to 7 % (significance only at α= 0.05). A stimulating effect of EA on the grain yield of winter wheat and winter rye was also obtained.
The positive influence of EA on the grain yield of spring barley was reproducible under the conditions of a limited water supply in small-scale plot experiments (increase of yield about 9 %).
In case of spring barley and winter rye the increase of the grain yield by EA, applied at growth stage 31 (= DC 31) was connected with a greater number of ear-bearing tillers. The increase of the winter wheat yield resulted from more grains per ear of the tillers.
The enhanced formation of tiller grain mass and total tiller biomass by EA was in correlation with a higher nitrogen import into tillers (r = 0.8
Possible stress reducing activities caused by EA are discussed. 相似文献
44.
Bastos EL Romoff P Eckert CR Baader WJ 《Journal of agricultural and food chemistry》2003,51(25):7481-7488
This paper describes a screening method for antioxidant potential determination based on luminol/hemin/hydrogen peroxide chemiluminescence. The emission depletion, caused by an antiradical compound added during the chemiluminescence decay, is proportional to the number of reactive species trapped. Therefore, the difference between the areas of the emission decay curves, obtained in the absence and in the presence of the potential antioxidant, is a measure for the antiradical capacity of the sample. The technique has been applied to measure the antiradical capacity of pure compounds and complex mixtures from natural origin, providing reliable results that indicate the method's feasibility. 相似文献
45.
采用标志重捕法在海拉尔东山上捕捉达乌尔黄鼠,确定年龄(根据牙齿磨损程度)、性别、数量,编制静态生命表以推测种群发展动态.研究表明,该地区中Ⅰ龄鼠占66.7%、Ⅱ龄鼠占20%、Ⅲ龄鼠占13.3%,年龄结构呈金字塔型,属于增长型种群,群体雄雌比例为1∶1.14,接近1∶1,种群中雌性略大于雄性. 相似文献
46.
People affected by coeliac disease need to adhere to a life-long gluten-free diet to avoid symptoms. ELISA-tests are seen as the mainstay for the detection of gluten in gluten-free food because of their sensitivity. They can, however, yield different gluten amounts depending on the antibody and reference material used. We compared the reactivity of three prominent mouse anti-gliadin-antibodies to a reference gliadin isolated from 28 common bred European wheat varieties. The reference material proteins were labelled with fluorescent dye Cy3. They were then separated by 2DE and transferred by Western blot onto low fluorescent PVDF-membranes, followed by incubation with the three primary anti-gliadin antibodies one by one. Detection of the reacting proteins used anti-mouse antibody which was labelled with fluorescent dye Cy5. The use of this technique made it possible to co-detect the 2DE-image of the reference material proteins (Cy3) and proteins reacting with the respective antibody (Cy5). The three investigated antibodies had dissimilar reactivities with different proteins of the reference gliadin. Antibodies R5 and PN3 reacted mainly with gliadin fractions, antibody 401.21 mainly with high molecular weight glutenins. The results confirm the individual specificity of these antibodies and demonstrate the importance of validating immunochemical methods for gluten detection. 相似文献
47.
Thomas Eckert Mahena Jhrling-Butkus Helen Louton Monika Burg-Roderfeld Ruiyan Zhang Ning Zhang Karsten Hesse Athanasios K. Petridis Tibor Kor Jürgen Steinmeyer Roland Schauer Peter Engelhard Anna Kozarova John W. Hudson Hans-Christian Siebert 《Marine drugs》2021,19(10)
Osteoarthritis belongs to the most common joint diseases in humans and animals and shows increased incidence in older patients. The bioactivities of collagen hydrolysates, sulfated glucosamine and a special fatty acid enriched dog-food were tested in a dog patient study of 52 dogs as potential therapeutic treatment options in early osteoarthritis. Biophysical, biochemical, cell biological and molecular modeling methods support that these well-defined substances may act as effective nutraceuticals. Importantly, the applied collagen hydrolysates as well as sulfated glucosamine residues from marine organisms were strongly supported by both an animal model and molecular modeling of intermolecular interactions. Molecular modeling of predicted interaction dynamics was evaluated for the receptor proteins MMP-3 and ADAMTS-5. These proteins play a prominent role in the maintenance of cartilage health as well as innate and adapted immunity. Nutraceutical data were generated in a veterinary clinical study focusing on mobility and agility. Specifically, key clinical parameter (MMP-3 and TIMP-1) were obtained from blood probes of German shepherd dogs with early osteoarthritis symptoms fed with collagen hydrolysates. Collagen hydrolysate, a chondroprotective food supplement was examined by high resolution NMR experiments. Molecular modeling simulations were used to further characterize the interaction potency of collagen fragments and glucosamines with protein receptor structures. Potential beneficial effects of collagen hydrolysates, sulfated glycans (i.e., sulfated glucosamine from crabs and mussels) and lipids, especially, eicosapentaenoic acid (extracted from fish oil) on biochemical and physiological processes are discussed here in the context of human and veterinary medicine. 相似文献
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50.
Objective To investigate the effects of two doses (200 and 400 mg) of a water-soluble gonadotrophin-releasing hormone vaccine on the ovarian activity of 2-year-old fillies.
Design A controlled vaccination dose rate experiment.
Animals Six 2-year-old Australian Stock Horse fillies were randomly allocated to three treatment groups: unvaccinated controls, those receiving 200 mg of the vaccine and those receiving 400 mg of the vaccine.
Results Ovarian activity of the treated fillies was suppressed at the peak of the breeding season while that of the untreated controls continued normally. The control fillies displayed oestrous activity and behaviour. Suppression of ovarian activity occurred for 25 and 30 weeks in the 200 and 400 mg groups, respectively. These differences were not significant. Ovarian activity ceased 2 to 3 weeks after primary vaccination. Antibody titres were low (330) until after the booster immunisation when they rapidly peaked at 22,000 and 28,000 in the 200 mg and 400 mg groups, respectively. Plasma progesterone concentrations of the treated fillies remained below 3.18 nmol/L while GnRH was suppressed. The vaccine had no significant effect on plasma androstenedione concentrations. Recovery from the effect of the vaccine was associated with development of ovarian follicles, normal oestrous behaviour and ovulation. Three of the four treated fillies and one of the controls conceived during the next breeding season and foaled normally. All the treated fillies conceived and produced normal foals in the following two breeding seasons.
Conclusion Both dose rates suppressed ovarian function and prevented oestrous behaviour. These effects were reversible and the subsequent fertility of the vaccinated fillies was normal. 相似文献
Design A controlled vaccination dose rate experiment.
Animals Six 2-year-old Australian Stock Horse fillies were randomly allocated to three treatment groups: unvaccinated controls, those receiving 200 mg of the vaccine and those receiving 400 mg of the vaccine.
Results Ovarian activity of the treated fillies was suppressed at the peak of the breeding season while that of the untreated controls continued normally. The control fillies displayed oestrous activity and behaviour. Suppression of ovarian activity occurred for 25 and 30 weeks in the 200 and 400 mg groups, respectively. These differences were not significant. Ovarian activity ceased 2 to 3 weeks after primary vaccination. Antibody titres were low (330) until after the booster immunisation when they rapidly peaked at 22,000 and 28,000 in the 200 mg and 400 mg groups, respectively. Plasma progesterone concentrations of the treated fillies remained below 3.18 nmol/L while GnRH was suppressed. The vaccine had no significant effect on plasma androstenedione concentrations. Recovery from the effect of the vaccine was associated with development of ovarian follicles, normal oestrous behaviour and ovulation. Three of the four treated fillies and one of the controls conceived during the next breeding season and foaled normally. All the treated fillies conceived and produced normal foals in the following two breeding seasons.
Conclusion Both dose rates suppressed ovarian function and prevented oestrous behaviour. These effects were reversible and the subsequent fertility of the vaccinated fillies was normal. 相似文献