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42.
Ryszard Oleszczuk Klaus Bohne Jan Szatylowicz Tomasz Brandyk Tomasz Gnatowski 《植物养料与土壤学杂志》2003,166(2):220-224
The shrinkage of the peat soils that accompanies the soil moisture changes is an important feature of such soils and has strong influence on their physical attributes and soil water management. The relationships between soil moisture and volume are often described using shrinkage characteristic curves by relating void ratio (volume of voids per unit volume of solids) to moisture ratio (volume of water per volume of solids). For conversion of soil volume changes into cracks volume and subsidence, a dimensionless shrinkage geometry factor is used. The paper presents results of volumetric shrinkage behavior and the geometry factor at various loads in sedge and alder peat soils. The measurements were conducted on undisturbed soil samples without applying a load and with loads corresponding to field overburden. The shape of the shrinkage characteristics of such soils were completely different from those of clay soils. The application of loads did not significantly influence the shrinkage characteristics curve. The applied load strongly influenced on relationship between shrinkage geometry factor and the moisture ratio, showing higher values of subsidence and lower values of crack volume in comparison with unloaded conditions. 相似文献
43.
Władysław Grodziński Jan Greszta Ryszard Laskowski Maciej Maryański Anna Rożen 《Water, air, and soil pollution》1990,53(1-2):169-178
The influence of dusts from aluminium (AP), zinc and lead (ZP1, ZP2), sintering (SP) and power (PP) plants on organic matter accumulation on the forest floor of a mixed oak-pine forest was studied in Niepo?omice Forest near Kraków, Poland. An artificial application of the dusts on experimental plots was used corresponding to 100, 500, 1000, 2000, and 5000 t km?2. Increased organic matter accumulation was observed 5 yr following the addition of AP, ZP1 and ZP2 dusts, while SP and PP dusts at levels > 100 t km?2 caused a slight decrease in litter accumulation. Statistical analysis indicated that Cd, Mn, Pb and Zn present in industrial dusts were responsible for the increase in litter accumulation, while some nutrients (e.g. K, Mg, Na) contained in the dusts might decrease organic matter storage to some extent. 相似文献
44.
A comparison and an evaluation of drain spacing equations for layered soils Drain spacings, calculated with different steady-state tile drainage formulas for layered soils, were compared. The formulas under consideration were those of Ernst, van Beers and of Toksöz and Kirkham. It was found that, for certain ranges of the drainage parameters, the drain spacings compare well. For other conditions, differences of over 100 percent did occur. Especially, results obtained with the Ernst equation may deviate considerably from those of the other authors. However, also drain spacings calculated with the van Beers equation do occasionally differ from those of Toksöz and Kirkham. For practical use the equation of Toksöz and Kirkham is recommended. 相似文献
45.
Gorinstein S Leontowicz H Lojek A Leontowicz M Ciz M Krzeminski R Gralak M Czerwinski J Jastrzebski Z Trakhtenberg S Grigelmo-Miguel N Soliva-Fortuny R Martin-Belloso O 《Journal of agricultural and food chemistry》2002,50(21):6102-6108
The effect of olive oils on lipid metabolism and antioxidant activity was investigated on 60 male Wistar rats adapted to cholesterol-free or 1% cholesterol diets. The rats were divided into six diet groups of 10. The control group (control) consumed the basal diet (BD) only, which contained wheat starch, casein, cellulose, and mineral and vitamin mixtures. To the BD were added 10 g/100 g virgin (virg group) or Lampante (Lamp group) oils, 1 g/100 g cholesterol (chol group), or both (chol/virg group) and (chol/Lamp group). The experiment lasted 4 weeks. Plasma total cholesterol (TC), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), triglycerides (TG), total phospholipids (TPH), HDL-phospholipids (HDL-PH), total radical-trapping antioxidative potential (TRAP), malondialdehyde lipid peroxidation (MDA), and liver TC were measured. Groups did not differ before the experiment. In the chol/virg and chol/Lamp vs chol group, the oil-supplemented diets significantly (P < 0.05) lessened the increase in plasma lipids due to dietary cholesterol as follows: TC (25.1 and 23.6%), LDL-C (39.3 and 34.7%), TG (19.3 and 17.0%), and TC in liver (36.0 and 35.1%) for the chol/virg and chol/Lamp group, respectively. The chol/virg and chol/Lamp diets significantly decreased the levels of TPH (24.7 and 21.2%; p < 0.05 in both cases) and HDL-PH (22.9 and 18.0%; p < 0.05 in both cases) for the chol/virg and chol/Lamp group, respectively. Virgin and Lampante oils in rats fed basal diet without cholesterol did not affect the lipid variables measured. Virgin, and to a lesser degree Lampante, oils have increased the plasma antioxidant activity in rats fed BD without cholesterol (an increase in TRAP, 20.6 and 18.5%; and a decrease in MDA, 23.2 and 11.3%, respectively). In the rats of chol/virg and chol/Lamp vs Chol diet groups the added oils significantly hindered the decrease in the plasma antioxidant activity (TRAP, 21.2 and 16.7%; and MDA, 27.0 and 22.3%, respectively). These results demonstrate that virgin, and to less degree Lampante, oils possess hypolipidemic and antioxidant properties. It is more evident when these oils are added to the diets of rats fed cholesterol. These positive properties are attributed mostly to the phenolic compounds of the studied oils. 相似文献
46.
Wojdyło A Oszmiański J Laskowski P 《Journal of agricultural and food chemistry》2008,56(15):6520-6530
There is considerable evidence to show that a greater intake of apple contributes to improved health by reducing the risk of diseases, such as cardiovascular disease and some forms of cancer. Apple fruit is a major source of phenol compounds, because its consumption is widespread in many countries and it is available on the market for the whole year. The phenolic composition of 67 varieties of apple cultivars (new and old varieties) was examined for the concentration of some important phytochemicals and antioxidant activity. For the first time, we have looked at the correlation and compared polyphenolic coumpounds in Golden Delicious variety and new varieties grown from it. Up to 18 compounds, including catechin, procyanidin, hydroxycinnamates, flavonols, anthocyanins, and dihydrochalcones, were analyzed by high-performance liquid chromatography with diode array detection analysis of crude extracts and after thiolysis and LC-MS. The mean content of total polyphenols lay between 523.02 and 2723.96 mg/100 g dw and depending upon the apples variety. Flavanols (catechin and oligomeric procyanidins) are the major class of apple polyphenols, representing more than 80%, followed by hydroxycinnamic acids (1-31%), flavonols (2-10%), dihydrochalcones (0.5-5%), and in red apples, anthocyanins (1%). In this study, the best correlation was found for the total polyphenols and ABTS method, with a lower correlation for FRAP and DPPH methods ( r = 0.871, 0.839, and 0.804, respectively). The presented data clearly demonstrated that new varieties, i.e., Ozark Gold, Julyred, and Jester, of apple had the same or higher value of bioactive compounds in comparison to the old varieties, i.e., Golden Delicious, Idared, and Jonagold. 相似文献
47.
Sylwester Czaplicki Dorota Ogrodowska Ryszard Zadernowski Iwona Konopka 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(2):198-204
An in vivo experiment was conducted to determine the effect of sea-buckthorn pulp oil feeding on the fatty acid composition of liver and adipose tissue of Wistar rats and the liver accumulation of retinol, its esters and α-tocopherol. For a period of 28 days, rats were given a modified casein diet (AIN-93) in which sea-buckthorn pulp oil, soybean oil and pork lard were used as sources of fat. Compared to the other fat sources, sea-buckthorn pulp oil was the most abundant in C16 fatty acids, carotenoids (mainly β-carotene) and tocopherols (mainly α-tocopherol). Its consumption was reflected in an increased share of palmitoleic acid in adipose tissue and the liver and an increased level of retinol in liver tissues (this was not observed for its esters). Although the type of fat did not have a significant effect on the average content of α-tocopherol in the liver, the variation of saturation of this tissue with α-tocopherol was the lowest when rats were fed a diet containing sea-buckthorn oil. This experiment indicates the possibility of affecting adipose tissue and liver by a diet. 相似文献
48.
49.
Brian David Craft Agnieszka Kosińska Ryszard Amarowicz Ronald Bruce Pegg 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(3):311-318
Raw, skinless peanut kernels from US commercial production lines were dry- and oil-roasted according to standard industrial practices. Eighty percent (v/v) methanolic extracts from the peanut cultivars were prepared and characterized by RP-HPLC: five predominant compounds were found comprising free p-coumaric acid and potential p-coumaric acid derivatives, as elucidated by DAD-UV spectra with comparisons to those of commercial standards. A Spanish high-oleic peanut possessed the greatest naturally-occurring level of p-coumaric acid and its derivatives, followed by a high-oleic Runner, a normal Runner, and a Virginia peanut. Upon thermal processing, p-coumaric acid was liberated at the expense of its derivatives according to the relationship: oil roasting > dry roasting > raw. A high-oleic Runner exhibited the greatest increase (~785%) in free p-coumaric acid levels after oil roasting. For many of the samples from the 2007 crop, processing increased the TPC and antioxidant capacities in the order of raw < dry roast < oil roast, but results were cultivar dependent. Oil-roasted peanuts were more effective at scavenging O2 ●- than their dry-roasted counterparts, as determined by a photochemiluminescence assay. Overall findings indicate that although thermal processing altered the composition of peanut kernel antioxidants, TPC values and radical-scavenging activities are preserved. Depending on peanut type, cultivar, and harvest date, enhanced antioxidant capacities can result. 相似文献
50.
Kevin Laskowski Kevin Frank Emily Merewitz 《Journal of Agronomy and Crop Science》2019,205(2):202-212
Annual bluegrass (Poa annua L; ABG) is susceptible to damage from ice cover. Effects of chemical treatments on ice survival under low temperature growth chamber conditions were studied. Field putting green plots of ABG were treated in the fall of 2014 and 2015 with Civitas, mefluidide, propiconazole or trinexapac‐ethyl (TE) at label rates. After acclimation, turfgrass cores from each plot were transferred to a low temperature growth chamber, received ice or no ice treatment and were sampled at 0, 20, 40 and 60 days. Ice was applied by misting plants at low temperature. In 2014, Civitas‐, mefluidide‐ and propiconazole‐treated plugs had the greatest amount of regrowth after ice and no ice treatments on most days; comparable results were found in 2015 but fewer statistical differences were detected. TE‐treated plants were no different from the untreated controls on most days in either year. Plants that were treated with mefluidide, propiconazole and Civitas had more polyunsaturated fatty acids (FA) in crown tissue, with linoleic acid approximately 50% greater compared to TE and untreated samples. Civitas, mefluidide or propiconazole treatments improved ABG survival of simulated ice conditions, which could be associated with the changes to saturated and unsaturated FA ratios that were observed in this study. 相似文献