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41.
Liquefaction of bagasse and cotton stalks was conducted by using polyhydric alcohols (polyethylene glycol PEG#400 and glycerin) in the presence of sulfuric acid (SA) as a catalyst. The effects of different liquefaction conditions, such as ratio raw material/liquefying solvent, effect of PEG#400/glycerin, acid concentration, liquefaction temperature and time on the liquefaction yield have been investigated. The hydroxyl and acid numbers for some liquefied samples were also determined. The results showed that the minimum residue content was obtained at 1/5 raw material to liquefying solvent. PEG#400 alone is not favoured as liquefying solvent as it gives ∼19% residual content for bagasse and ∼22% for cotton stalks at the optimum studied reaction conditions. Replacing 10% of PEG#400 with glycerin as well as increasing the SA concentration, liquefaction temperature or time, decreased the amount of residue for both bagasse and cotton stalks to less than 10%. The hydroxyl number of the produced polyols slowly decreased from 253 to 223 mg KOH/g on extending the reaction time till 120 min and the residual polyols prevented re-condensation of the liquefied components. It seems that this system can be applied on various types of lignocellulosic agricultural residues.  相似文献   
42.
Personalien     
Ohne Zusammenfassung  相似文献   
43.
    
Ohne Zusammenfassung
Observations On The Effect Of Insecticides On Coleopterous Predators OfErioischia Brassicae (Diptera: Anthonmyiidae). Beobachtungen über die Wirkung von Insektiziden auf Prädatoren(Coleoptera) vonErioschia brassicae (Diptera: Anthomyiidae)
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44.
Wood specimens of Casuarina glauca were inoculated withChaetomium spp. andTrichoderma spp., alone or in combination in the presence or abscence of larvae ofStromatium fulvum. All fungal inoculates caused deterioration to the lignin of the wood specimens. The infestation with larvae alone caused the same. The extractive content decreased to a little extent.
Zusammenfassung Bäume von Casuarina glauca wurden mitChaetomium spp. undTrichoderma spp. inokuliert, allein oder in Kombination sowie in Abwesenheit oder Gegenwart der Larven vonStromatium fulvum. Alle Pilz-Inokulate verusachten einen Abbau von Lignin in den Bäumen. Denselben Effekt hatte die Tätigkeit vonStromatium-Larven ohne Pilz-Inokulation. Der extraktive Anteil verminderte sich nur wenig.


With 2 tables  相似文献   
45.
In this paper through digestive and metabolic experiments studied the voluntary intake and apparent digestibility of cottonseed hulls (kernel-contained CH,kernel-free CH) and cornstalk on sheep to evaluate the nutrition value and digestion characteristics of cottonseed hulls.12 of adult Xinjiang merino rams were selected and divided into two groups (n=6 each group),and on the basis of 300 g/(head·day) of mixed concentrate,fed with kernel-free CH by 400 (group 1) or 800 (group 2) g/(head·day) respectively,to estimate the digestibility of CH by difference method;As well,another 18 of adult Xinjiang merino rams were selected and divided into three groups (n=6 each group),and on the basis of 300 g/(head·day) of mixed concentrate,cafeteria feeding with kernel-contained CH (group 3),kernel-free CH (group 4) or ground cornstalks (group 5) respectively,to study the effects of three diets on the voluntary intake,digestion and metabolism of sheep.The results showed that the apparent digestibility of the DM,OM,CP,cellulose,hemicellulose and energy of kernel-free CH by sheep were 46.71%,47.37%,-53.40%,66.60%,62.48% and 42.59%,respectively.There were no significant differences in the intake of DM,OM,cellulose,hemicellulose,energy and Ca between kernel-contained CH and kernel-free CH groups (P> 0.05);Intake of CP and P in kernel-contained CH group were extremely significantly higher than that in kernel-free CH group (P< 0.01);Intake of lignin in kernel-contained CH group was extremely significantly lower than that in kernel-free CH group (P< 0.01).There were no significant differences in the apparent digestibility of DM,OM and energy between kernel-contained CH and kernel-free CH groups (P> 0.05).The apparent digestibility of cellulose and hemicellulose in kernel-free CH group were significantly and extremely significantly higher than that in kernel-contained CH group (P< 0.05;P< 0.01),respectively.The apparent digestibility of CP in kernel-contained CH group was extremely significantly higher than that in kernel-free CH group (P< 0.01).The apparent digestibility of DM,OM,CP,cellulose and energy in ground cornstalks group were extremely significantly higher than that in kernel-contained CH and kernel-free CH groups (P< 0.01),however,the apparent digestibility of Ca and P were lower than that in kernel-contained CH and kernel-free CH groups (P> 0.05).Intake and retention of nitrogen in kernel-contained CH group were extremely significantly higher than that in kernel-free CH group (P< 0.01);The was no significant difference in the retention of nitrogen between kernel-free diet group and cornstalk diet group (P> 0.05).It was concluded that CH was a kind of special forage with larger intake,higher digestibility on the fiber substances and energy,but with a serious obstruction on protein digestion;The nutritional value between kernel-free diet and cornstalk diet was almost equal,and with lower nitrogen digestibility on kernel-free diet.  相似文献   
46.
Morinda citrifolia (noni) is known to contain genotoxic anthraquinones in the roots. Because of the widespread use of noni juice, the possible genotoxic risk was examined through a battery of short-term tests. Noni juice was also chemically analyzed for the possible presence of anthraquinones. Noni juice extract in the Salmonella microsome assay showed a slight mutagenic effect in strain TA1537, due to the presence of flavonoids. No mutagenicity was observed in the mammalian mutagenicity test with V79 Chinese hamster fibroblasts. Rats treated with a noni juice concentrate did not show DNA repair synthesis (UDS) in primary rat hepatocytes, nor could DNA adducts or DNA strand breaks be observed. HPLC analysis of noni juice for anthraquinones was negative, with a sensitivity of <1 ppm. In summary, chemical analysis and genotoxicity tests reveal that noni juice does not have a genotoxic potential and that genotoxic anthraquinones do not exist in noni juice.  相似文献   
47.

Background

Bluetongue virus (BTV) is an insect-transmitted virus, which causes bluetongue disease (BT) in sheep and a fatal hemorrhagic infection in North American white-tailed deer. However, in cattle the disease is typically asymptomatic and no overt clinical signs of disease appear to be associated with BTV infection. Serological evidence and isolation of different BTV serotypes have been reported in Sudan, however, no information is currently available in regard to previous exposure of Sudanese livestock to BTV infection in East Darfur State, Sudan.

Aims

To determine the prevalence of BTV antibodies and to identify the potential risk factors associated with BTV infection among cattle in East Darfur State, Sudan.

Methods

A total of 224 blood samples were collected randomly from five localities in East Darfur State, Sudan. The serum samples were screened for detection of BTV-specific immunoglobulin G (IgG) antibodies using a competitive enzyme-linked immunosorbent assay (c-ELISA).

Results

Serological evidence of BTV infection was observed in 150 out of 224 animals accounting for a 67% prevalence rate among cattle in East Darfur State. Older cattle (>2 years of age) were six times more likely to be infected with BTV (OR = 6.62, CI = 2.87-15.26, p-value = 0.01). Regarding animal source (contact with other herds) as a risk factor, it was shown that cattle purchased from market or introduced from other herds were 3 times at higher risk of being infected with BTV (OR = 3.87, CI = 1.07-13.87, p value = 0.03). Exposure of cattle to the insect vector increased the risk of contracting BTV infection by six times compared to non-exposed cattle (OR = 6.44, CI = 1.53-27.08, p value = 0.01).

Conclusion

The present study indicated that age, animal source and the intensity of the insect vector are influential risk factors for BTV infection in cattle in the Darfur region. Surveillance for BTV infection should be extended to include other susceptible ruminants and to study the distribution of the insect vectors to better predict and respond to a possible BTV outbreak in the State of East Darfur, Sudan.  相似文献   
48.

In the North Nile Delta of Egypt, the impacts of overplanting paddy rice on water delivery performance have not been discussed quantitatively. Further, the amount of water that could have been saved if farmers would follow the planned area is unknown. In this study, water delivery performance was assessed by comparison of actual paddy rice planting and the government’s planned conditions. For both conditions, performance indicators relating to adequacy, equity, and dependability were analyzed across six locations in conjunction with the branch canal water level in 2013 and 2014. Based on the difference between the actual water supply and planned water demand, the amount of water that could have been saved for downstream uses was calculated. The average adequacy for the investigation period was good at one location, fair at 2 locations, and poor at 3 locations in both years. Further, adequacy under both actual and planned conditions was poor in late July at all locations. The planned adequacy and dependability downstream and equity among locations improved compared to the actual condition in both years. Under the condition that paddy rice area is the upper limit planned by the government, about 12.3% and 9.6% of water could be potentially saved in each year. The difference between actual and planned water delivery performance is caused by the branch canal’s low water level. Control of overplanting paddy rice and coordination of water distribution among water user associations would improve stable water level in the canal and, eventually, water delivery performance.

  相似文献   
49.
The effect of N levels and sources on the antioxidant components in vegetable is not completely understood. Therefore, greenhouse experiments were conducted to determine the changes in antioxidant capacity diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP), total phenolics, ascorbic acid, total carotene and lycopene contents in edible portions of lettuce, onion and tomato due to different nitrogen levels and sources. The experiment included three N levels (20, 40 and 60 kg/ha for lettuce trial and 60, 120 and 180 kg/ha for either onion or tomato) and four nitrogen sources (calcium nitrate, ammonium sulphate, ammonium nitrate and urea). The antioxidant capacity and phenolic contents in lettuce was enhanced under low nitrogen level, while the antioxidant capacities, phenolics, carotenoids and lycopene in tomato fruits were not significantly affected by the nitrogen dose applied. Application of calcium nitrate caused 50% increase in DPPH and 20% in FRAP of lettuce compared to other nitrogen forms. Tomato treated with calcium nitrate or ammonium sulphate had higher phenolic and ascorbic acid contents than treated plants with ammonium nitrate or urea. Antioxidant tested parameters of onion were not significantly affected by the nitrogen treatments. Nitrogen concentration in tomato fruits significantly correlated with FRAP antioxidant capacity, phenolics, ascorbic acid, carotene and lycopene contents.  相似文献   
50.
This study sought to isolate and characterize lactic acid bacteria (LAB) from stomach of adult snakehead fish, Channa striatus, to be used as probiotics for freshwater fish. A total of 13 strains were isolated from the stomach of 10 fish, and 4 of these belonged to LAB. Strain LAB‐3 showing highest in vitro growth inhibition of Aeromonas hydrophila in a disk diffusion test was identified as Lactobacillus fermentum by conventional and molecular techniques and evaluated in vitro through various tests. The bacterium could grow at pH 3–8; but the optimum growth was observed at pH 6. Moreover, LAB‐3 grew at 0.15 and 0.3% bile salt concentrations, from 15 to 45 C, and at 4% NaCl. L. fermentum showed in vitro inhibitory activity against three fish pathogens, A. hydrophila, Pseudomonas aeruginosa, and Shewanella putrefaciens, tested by disk diffusion and well diffusion methods. Antibiotic sensitivity tests indicated that L. fermentum was resistant to streptomycin, gentamycin, and kanamycin, intermediate to tetracycline, but sensitive to chloramphenicol, amoxicillin, and ampicillin. Challenge test by using A. hydrophila showed that survival of snakehead was significantly (P < 0.05) improved when 2 × 106 LAB‐3/g was supplemented to the diet. Therefore, this study suggests that L. fermentum might be a promising probiotic in snakehead aquaculture .  相似文献   
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