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991.
Jorge Gominho Ana Lourenço Maria Curt Jesús Fernández Helena Pereira 《Industrial Crops and Products》2009,29(1):116-125
The capitula of Cynara cardunculus contain hairs and pappi representing 7% of the total plant biomass. These low density biomass components could be mechanically separated without apparent losses using a whole-plant processing prototype. Hairs and pappi are filamentous structures made up of longitudinally aligned fibre cells, without intercellular voids or pitting, with the following dimensions regarding length, width and wall thickness: 1.35 mm, 19.8, and 4.8 μm for hairs and 1.78 mm, 10.4, and 2.9 μm for pappi. Chemically hairs and pappi have low content of ash (1.9% and 1.1%, respectively), extractives (5.4% and 6.0%) and lignin (10.6% and 17.8%), and high content of holocellulose (77.5% and 72.8%) and α-cellulose (55.2% and 46.8%).Pulps could be produced using a conventional kraft process with high yields and low residual lignin, e.g. 63% at Kappa 7 for hairs and 48% at Kappa 11 for pappi, low coarseness values (0.04 and 0.03 mg m?1) and adequate pulp properties for paper (40 and 42 N mg?1 tensile index; 3.6 and 3.4 kPa m2 g?1 burst index in unrefined pulps of hairs and pappi, respectively). The results also indicated that there is scope for improving pulp quality by optimising pulping conditions to this type of new raw materials. The differences between hairs and pappi may also be further exploited namely the lower lignin content of hairs and the higher slenderness and wall thickness of pappi fibres.The utilization of hairs and pappi may strengthen the differentiated use of biomass fractions of the Cynara plant and its potential as a bioenergy crop. 相似文献
992.
D. Mar Seeholzer 《Forstwissenschaftliches Centralblatt》1937,59(3):69-77
Ohne ZusammenfassungVortrag im naturwissenschaftlichen Berein Aschaffenburg 1936. 相似文献
993.
Mohammad Mustafizur Rahman Marc Verdegem Leo Nagelkerke Md Abdul Wahab Ana Milstein & Johan Verreth 《Aquaculture Research》2008,39(1):85-95
The effects of introducing common carp (CC) and of adding artificial feed to fertilized rohu ponds on water quality and nutrient accumulation efficiency were studied. All ponds were stocked with 15 000 rohu ha?1. Treatments included ponds with rohu alone, rohu plus 5000 common carp ha?1 and rohu plus 10 000 CC ha?1. A comparison was also made between supplementally fed and non‐fed ponds. The overall highest nitrogen (N) and phosphorus (P) concentrations were observed in ponds with 5000 CC ha?1, followed by ponds with 10 000 and 0 CC ha?1. The largest fractions of N and P inputs accumulating in fish, phytoplankton and zooplankton were observed in ponds with 5000 CC ha?1, followed by ponds with 10 000 CC ha?1 and subsequently ponds without CC. Relatively more nutrients accumulated in benthic organisms in ponds without than in ponds with CC. A smaller fraction of the nutrient input was retained in fish, plankton and benthic organisms in ponds without CC compared with ponds with CC. Compared with 5000 CC ha?1, stocking 10 000 CC ha?1 can be considered as overstocking, because this leads to lower fish production and relatively less nutrients retained in plankton and benthic organisms. 相似文献
994.
Domingo Martínez-Romero Fabián Guillén Salvador Castillo Pedro Javier Zapata María Serrano Daniel Valero 《Postharvest Biology and Technology》2009,51(2):200-205
A scrubber to remove ethylene continuously from stored environments was developed. The device comprised a cartridge heater tightly joined to the activated carbon–1% Pd. The application of heat pulses led to an increase in ethylene oxidation and to auto-regeneration of the activated carbon. The efficacy of ethylene removal was higher with the number of heat pulses. Several combinations of exogenous ethylene concentrations and heater core temperatures (100–325 °C) of the device were assayed to determine their effectiveness in removing ethylene from the storage area. The results indicated that increasing the heater temperature led to enhanced percentages of eliminated ethylene but also increased CO2 concentrations. This CO2 could come from the activated carbon due to its breakthrough. Thus, temperatures ranging between 150 and 200 °C eliminated 96–99% of ethylene, with low CO2 accumulation (0.10–0.18 kPa) and without affecting the temperature of the storage environment. Thus, this device might be a promising tool for scrubbing ethylene from storage areas for fresh horticultural produce in which ethylene can induce detrimental effects. 相似文献
995.
Enrique Perez Patricia A. Conrad David Hird Ana Ortuno Jorge Chacon Robert BonDurant Jos Noordhuizen 《Preventive veterinary medicine》1992,14(3-4):155-165
Two studies (one pilot and one cross-sectional) were conducted in the two main livestock-rearing areas of Costa Rica using an improved method (In-Pouch TF) for the detection of Trichomonas foetus infection in bulls. Herd prevalence rates of 6.7% (6/98) and 15.9% (10/63), and bull prevalence rates of 3.9% (6/153) and 6.2% (14/225) were found in the pilot and cross-sectional studies, respectively. Adjusted prevalences in the cross-sectional study were 18.4% and 7.2% for aarms and bulls, respectively. Breed (Bos taurus) and age (over 4 years) were the main risk factors identified using random-effects logistics regression. The nature of the disease and the high prevalence indicated that trichomoniasis could have a serious economic impact on cattle production in Costa Rica. 相似文献
996.
Francisco J Salguero Segundo Fayna Díaz-San Alejandro Brun María J Cano Juan M Torres 《Journal of veterinary diagnostic investigation》2006,18(1):106-109
Confirmatory diagnosis of prion diseases in humans and animals relies on the histopathological examination and immunodetection of the protease-resistant isoform of prion protein (PrPres). The generation of novel PrP-specific monoclonal antibodies (MAbs) has greatly improved diagnostic methodology and basic research on prion diseases as well. In this study, the performance of 3 different PrP-specific MAbs in recognizing brain PrPres deposits from cows affected with bovine spongiform encephalopathy (BSE) was compared by using a standard immunohistochemical technique under different pretreatment conditions. All antibodies showed similar reactivity after denaturing treatment. However, greater differences were found among them after proteinase K treatment, even in the absence of a denaturing step. In fact, 1 MAb (2A11) was able to react with PrPres deposits in the absence of a denaturing step, yielding the strongest signal and confirming the usefulness of MAb 2A11 in immunohistochemistry for the diagnosis of BSE. 相似文献
997.
Juana Ortiz Rocío Ruiz de Ybá?ez Teresa Abaigar Marina Goyena Magdalena Garijo Gerardo Espeso Mar Cano 《Journal of zoo and wildlife medicine》2006,37(3):249-254
Feces from 62 captive African gazelles, including Mhorr gazelles (Gazella dama mhorr), Cuvier's gazelles (Gazella cuvieri), and Dorcas gazelles (Gazella dorcas neglecta), were examined over the course of a year to quantitate nematode egg excretion patterns. Strongyloides sp. eggs appeared only in G. dama during the rainy season. Trichostrongylidae egg excretion showed a marked seasonal variation, with very low levels during the dry and hot period, a finding that is probably attributable to hypobiosis of the predominant species (Camelostrongylus mentulatus). Eggs of the Nematodirus sp., predominantly Nematodirus spathiger, were excreted throughout the year. No seasonal pattern was observed in Trichuris sp. egg excretion. 相似文献
998.
G A Erickson C J Maré G W Beran E A Carbrey 《American journal of veterinary research》1978,39(1):105-107
Pet birds of 6 species were exposed to a psittacine isolate to viscerotropic velogenic Newcastle disease (VVND) virus to evaluate the impact of VVND in those species. Species examined were the budgerigar, yellow-headed Amazon parrot, canary, halfmoon conure, lesser hill mynah, and blackheaded nun. Five of the 6 species were highly susceptible to infection with VVND virus. Canaries were relatively refractory to infection with the virus. Contact birds of the same species developed infections almost as rapidly as did the birds directly exposed to nebulized VVND virus. Mortality was most marked for the conures. Less than half of the parrots exposed to nebulized virus died of VVND. Of the directly exposed budgerigars, mynahs, and nuns, 16% to 22% died during an observation period of postexposure days 0 through 28. 相似文献
999.
1000.