Investigation on acoustic behavior and air permeability of struto nonwovens     

Tao Yang  Xiaoman Xiong  Rajesh Mishra  Jan Novák  Jiří Chaloupek  Filip Sanetrnik  Jiří Militký 《Fibers and Polymers》2016,17(12):2078-2084

This work deals with the study of acoustic performance of struto nonwovens and their relation to fabric air permeability. In order to achieve the objective of the research, sound absorption coefficient of struto nonwovens was determined via impedance tube method, the average value of sound absorption coefficient (α?) was calculated. Air permeability of struto nonwovens was examined by using FX3300 Textech Air Permeability Tester. Results showed that struto nonwoven exhibited good absorption ability at frequency bands 3000-6400 Hz while it was ineffective for frequency lower than 3000 Hz. Struto nonwovens with high GSM and fabric thickness showed better acoustic performance and lower air permeability. It was observed that α? was inversely proportional to air permeability, with correlation coefficient 0.95. It was concluded that air permeability can be used as a criterion of sound absorption behavior of struto nonwovens. A lower air permeability suggests a better sound absorption performance for struto nonwoven fabrics.  相似文献   

Effects of herbal preparation on libido and semen quality in boars     

Frydrychová S  Opletal L  Macáková K  Lustyková A  Rozkot M  Lipenský J 《Reproduction in domestic animals》2011,46(4):573-578

The objective of this study was to investigate the effects of a preparation from herbal extracts (PHE) on libido and semen quality in breeding artificial insemination boars. Ten fertile boars were divided into control and experimental groups according to significant difference of libido. There were no differences in semen quality between groups. Animals were fed a commercial feeding mixture for boars. The feeding mixture for the experimental group was enriched with PHE, which was prepared from Eurycoma longifolia, Tribulus terrestris and Leuzea carthamoides. Duration of the experiment was 10 weeks. Samples of ejaculate were collected weekly. Libido was evaluated according to a scale of 0-5 points. Semen volume, sperm motility, percentage of viable spermatozoa, sperm concentration, morphologically abnormal spermatozoa, daily sperm production and sperm survival were assessed. Amounts of mineral components and free amino acids were analysed in seminal plasma. Significant differences were found in these parameters: libido (4.05 ± 0.22 vs 3.48 ± 0.78; p < 0.001), semen volume (331.75 ± 61.91 vs 263.13 ± 87.17 g; p < 0.001), sperm concentration (386.25 ± 107.95 vs 487.25 ± 165.50 × 10(3) /mm(3); p < 0.01), morphologically abnormal spermatozoa (15.94 ± 11.08 vs 20.88 ± 9.19%; p < 0.001) and Mg concentration (28.36 ± 11.59 vs 20.27 ± 13.93 mm; p < 0.05). The experimental group's libido was increased by 20% in comparison with the beginning of the experiment. Results of this study showed positive effect of PHE on libido and some parameters of boar semen quality.  相似文献   

Manure application followed by biochar application increases plant production regardless of soil dehydrogenase activity     

H. Dvořáčková  J. Dvořáček 《Soil Use and Management》2023,39(4):1557-1569

Biochar is obtained by the pyrolysis of biomass, and contains abundant carbon and minerals. Biochar supplementation of soils can greatly improve soil health and quality, but these beneficial effects typically develop slowly over time. Depending on the quality of the biochar and the soil to which it is applied, it may take years before positive effects are apparent. This is because organic substances are slowly sorbed onto the biochar over time, and the biochar eventually becomes part of the sorption complex of the soil. It is therefore advisable to apply biochar together with some organic material. We examined the effect of co-application of different doses of biochar with manure on soil dehydrogenase activity (DHA), soil oxidizable carbon (COX), cumulative soil respiration, soil buffering capacity, the soil exchange reaction (pH/KCl) and the production yield of winter rape seeds. We also determined seed production when artificial granular fertilizers were added to biochar and manure. The results showed that the application of biochar and manure significantly increased grain yield, DHA, the soil exchange reaction and cumulative respiration. Thus, application of biochar with organic material can increase seed yield and some properties of agricultural soils. However, the positive effect of biochar on seed yield was not directly proportional to biochar dose, in that the seed yield was lower for a biochar dose of 45 t/ha than 30 t/ha.  相似文献   

Soil organic matter in water-stable aggregates under different soil management practices in a productive vineyard     

Vladimír Šimanský 《Archives of Agronomy and Soil Science》2013,59(9):1207-1214

In a productive vineyard, the influence of different soil management practices on carbon sequestration and its dynamic in water-stable aggregates of Rendzin Leptosol was studied. In 2006, an experiment of different management practices in a productive vineyard was established in the locality of Nitra-Dra?ovce, in the Nitra winegrowing area of Slovakia. The following treatments were established: (1) control (grass without fertilization); (2) T (tillage); (3) T + FM (tillage + farmyard manure); (4) G + NPK3 (grass + NPK 120–55–195 kg ha^?1); and (5) G + NPK1 (grass + NPK 80–35–135 kg ha^?1). The results showed that the lowest soil organic matter content (9.70 g kg^?1) in water-stable microaggregates was determined in G + NPK3, as well as in T. However, the highest soil organic matter content in the highest size fractions of water-stable macroaggregates (>5 mm) was observed in T + FM (19.7 g kg^?1). The highest value for carbon sequestration capacity in water-stable microaggregates was observed in the ploughed farmyard manure treatment. However, the control treatment showed the highest values for carbon sequestration capacity in water-stable macroaggregates, including agronomically favourable size fractions (0.5–3 mm). In all soil management practices under a productive vineyard the most intensive changes in the soil organic matter content were observed in the highest size fractions (>3 mm) of water-stable macroaggregates.  相似文献   

Total organic carbon and its composition in long-term field experiments in the Czech Republic     

Jaromír Kubát  Dana Cerhanová  Jitka Nováková  Jan Lipavský 《Archives of Agronomy and Soil Science》2013,59(5):495-505

Abstract

Total organic carbon content and its composition have been evaluated in the topsoil in the selected plots of 13 long-term field experiments conducted in different soil and climate conditions. The altitude of the sites ranged from 225 – 670 m above sea level. Four variants of the organic and mineral fertilization were selected in each experiment: Nil, which did not receive any organic or mineral fertilizers since the beginning of the experiment, mineral fertilized variant NPK, organic fertilized (manured) variant FYM and both organic and mineral fertilized variant FYM + NPK. Total organic carbon (C) content in the topsoil differed as a result of the soil and climate conditions (it ranged from 0.96 – 1.80% C in the Nil variants) and due to the organic and mineral fertilization. The inert and decomposable part of the soil organic C content was calculated and the hot water soluble carbon content was determined. Relationships between the individual SOM fractions have shown a highly significant correlation, except for the decomposable C calculated as a difference to Nil variant.  相似文献   

Fate of humic acids isolated from natural humic substances     

Lubica Pospíšilová  Markéta Komínková  Ondřej Zítka  René Kizek  Gabriela Barančíková  Tadeáš Litavec 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(6):517-528

Composition of humic acids (HA) is a function of plant-derived inputs, degradation processes regulated by microorganisms, organo-mineral interactions and age. Characterization of different origin humic substances is important for evaluation of their contribution to stabile and labile carbon pool in the environment. The relative abundance of chemical components in HA isolated from soils, compost, commercial lignohumates, alginite, acadiane and lignite was studied with aim to quantify content of important biomarkers such as amino acid, lipids and polyphenols. HA were considered as a heterogeneous complex and high concentration of peptides, polyphenols and lipids was determined in acadian-HA to compare with soil-HA. Compost-HA contained much more amino acids to compare with soil-HA samples. Alginite-HA and lignite-HA were similar in biomarkers content to soil-HA. Fourier transform infrared spectroscopy confirmed that chemical composition and functional groups content differs with the origin, humification degree and the age of studied samples. Soil-HA are typically composed of a variety of ?OH, COOH?, C–O, C–H₂, (aliphatic and aromatic) groups, quinines, lignin fragments, polysaccharide, monosaccharide and proteins fragments, which are linked together by ?O?, ?NH?, ?H=, >C=O, metal ions and –S? groups. ¹³C NMR spectroscopy showed that aromatic carbon content was the highest in lignite-HA and soil-HA.  相似文献   

Understanding pathogen population structure and virulence variation for efficient resistance breeding to control cucurbit powdery mildews     

Aleš Lebeda  Božena Sedláková  Eva Křístková  Mark P. Widrlechner  Evsey Kosman 《Plant pathology》2021,70(6):1364-1377

Cucurbit powdery mildew (CPM) is caused most frequently by well-differentiated obligate erysiphaceous ectoparasites Golovinomyces orontii and Podosphaera xanthii, which vary in their ecology and virulence. All economically important cucurbit crops host both of these CPM species. Breeding of cucurbits for CPM resistance is highly important worldwide, but adequate knowledge of CPM species determination, as well as virulence structure, population dynamics, and spatiotemporal variation of these pathogens, has not yet been achieved. New tools have been developed to enhance research on CPM virulence variation for more efficient breeding and seed and crop production. A set of differential genotypes of Cucumis melo, with high differentiation capacity, may contribute substantially to understanding of variation in CPM virulence at both individual and population levels. Long-term observations (2001–2012) of CPM pathogens in the Czech Republic were used to analyse virulence variation within and among annual CPM populations and demonstrate the utility of recently developed tools for studying species variability and virulence variation of CPM pathogens worldwide. Detailed analyses of diversity and spatiotemporal fluctuations in the composition of CPM populations provide crucial information for shaping breeding programmes and predicting the most effective sources of race-specific resistance. The primary aim of this work was to create a uniform framework for determination of CPM species structure and diversity, virulence phenotypes, virulence and phenotype frequencies, phenotype complexity, dynamics, and variation within and among CPM populations. In addition, practical advice is presented on how to select the most relevant data and interpret them for use in cucurbit resistance breeding.  相似文献   

The legacy of acidic deposition controls soil organic carbon pools in temperate forests across the Czech Republic     

Tomáš Chuman  Filip Oulehle  Kateřina Zajícová  Jakub Hruška 《European Journal of Soil Science》2021,72(4):1780-1801

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Antioxidant Enzymes in Barley Green Biomass     

J. Ehrenbergerová  N. Březinová Belcredi  J. Kopáček  L. Melišová  P. Hrstková  S. Macuchová  K. Vaculová  I. Paulíčková 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(2):122-128

Green biomass of young barley plants exhibited statistically significant higher activity of superoxide dismutase (SOD) and catalase (CAT) at sampling I (in the phase of plant development DC 29) compared to the later sampling II (DC 31). Significant effects of varieties, years and interactions of the studied factors on the activity of the studied antioxidants were determined. During the experiment period (2005–2007), the variety Sebastian provided statistically significant higher average SOD activity (486 U.g-1) versus the variety Malz (416 U.g-1 dry matter) and line KM1910 (418 U.g-1 dry matter). No statistically significant difference was recorded between the latter two varieties. Average catalase activity of the varieties did not show any significant difference. Significantly higher CAT activity in the sampling I was recorded on average of years and locations in the variety Sebastian and hull-less line KM1910 (935 and 907 U.g-1) compared to the variety Malz (675 U.g-1). We can state that green biomass of young spring barley plants taken during the growth phase DC 29 was a significant source of enzymes catalase and superoxide dismutase in the course of the experiment (2005–2007).  相似文献   

Genetic mapping of a new flowering time gene on chromosome 3B of wheat     

Kateřina Pánková  Zbyněk Milec  James Simmonds  Michelle Leverington-Waite  Lesley Fish  John W. Snape 《Euphytica》2008,164(3):779-787

The single chromosome substitution lines of chromosome 3B of the Czech alternative wheat variety Česká Přesívka (CP 3B) into two spring varieties Zlatka and Sandra, revealed clear differences in flowering time compared to the recipient varieties. To map this gene(s), recombinant substitution lines for chromosome 3B were produced from crosses of the substitution lines with their recipient parents and genetic maps developed using SSR markers. Two populations were mapped, Sandra//Sandra 3B/Sandra (CP 3B) and Zlatka//Zlatka/Zlatka (CP 3B). Combining the genotype data with phenotype data on flowering time in five independent experiments under natural long day or controlled short day conditions revealed a single flowering time QTL. This gene had an additive effect of 1–6 days, depending on environment and genetic background, and was mapped in both populations to a position in the region of marker Xbarc164 near the centromere on the long arm of 3B. Comparisons of the genetic maps with other 3B maps developed by the authors indicated that the QTL may be homologous to a QTL segregating in UK germplasm.  相似文献