• Korean Journal of Medicinal Crop Science
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• v.15 no.3
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• pp.194-198
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• 2007

Yield and ginsenoside contents of ginseng (Panax ginseng C. A. Meyer) is affected by light intensity and quality, and the color and the thickness of PE shading net when PE net is utilized for shading material. This study was carried out to investigate the effect of light quality on root yield and ginsenoside contents off-year-old ginseng by using polyethylene shading net with each blue and yellow color, Spectral irradiance under blue and yellow shading net showed the peak at 498 nm and 606 nm, respectively, which made distinct difference in light quality. Heat injury ratio of blue shading net was increased distinctly more than that of yellow shading net in summer season because of higher transmitted quantum (23%)and air temperature (0.3 $^{\circ}$C) in blue shading net than those of yellow shading net. Chlorophyll content and leaf area under yellow shading net were higher than those of blue shading net, and its heat injury ratio was lower than those of blue. These effects may led to 48% higher increase of root yield under yellow shading net than that under blue shading net. The content of total ginsenoside in taproot was not significantly differed between blue and yellow shading net, while the content in lateral and fine root was significantly increased in blue shading net compared to yellow shading net. PDM ratio of blue shading net showed more significant increase in lateral root than that of yellow shading net. All of Rb$_1$/Rg$_1$ ratio in three parts of root under blue shading net was higher than that of yellow shading net, but there were no significant increase in the ratio of lateral root.

• Applied Chemistry for Engineering
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• v.9 no.4
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• pp.497-503
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• 1998

The catalytic oxidation of 1.2-dichloroethane was investigated over precious metal supported on alumina using a fixed bed microreactor. Among the catalysts tested, the conversion of 1.2-dichloroethane decreased in the following order : Ru > Pt > Pd $${\sim_=}$$ Rh and Pt was found to be the most active catalyst for the complete oxidation of 1.2-dichloroethane to $CO_2$. Major products containing carbon were vinyl chloride and $Co_2$ at temperature ranging from 200 to $400^{\circ}C$. The presence of vinyl chloride in products suggests that the first step in the oxidation of 1.2-dichloroethane is dehydrochlorination and the second is oxidation of vinyl chloride to $CO_2$. To investigate the effect of HCl on the activity of the complete oxidation, some experiments were conducted by adding HCl to the feed. The presence of HCl increased the conversion of 1.2-dichloroethane below $300^{\circ}C$ owing to the increase of surface acidity, but it didn't affect the conversion above $300^{\circ}C$. The reversible adsorption of HCl onto catalyst surface inhibited the complete oxidation to $CO_2$.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.11
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• pp.1619-1637
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• 2000

A review was undertaken to obtain information on the range of beak-trimming methods available or under development. Beak-trimming of commercial layer replacement pullets is a common yet critical management tool that can affect the performance for the life of the flock. The most obvious advantage of beak-trimming is a reduction in cannibalism although the extent of the reduction in cannibalism depends on the strain, season, and type of housing, flock health and other factors. Beak-trimming also improves feed conversion by reducing food wastage. A further advantage of beak-trimming is a reduction in the chronic stress associated with dominance interactions in the flock. Beak-trimming of birds at 7-10 days is favoured by Industry but research over last 10 years has shown that beak-trimming at day-old causes the least stress on birds and efforts are needed to encourage Industry to adopt the practice of beak-trimming birds at day-old. Proper beak-trimming can result in greatly improved layer performance but improper beak-trimming can ruin an other wise good flock of hens. Re-trimming is practiced in most flocks, although there are some flocks that only need one trimming. Given the continuing welfare scrutiny of using a hot blade to cut the beak, attempts have been made to develop more welfare friendly methods of beak-trimming. Despite the developments in design of hot blade beak-trimmers the process has remained largely unchanged. That is, a red-hot blade cuts and cauterises the beak. The variables in the process are blade temperature, cauterisation time, operator ability, severity of trimming, age of trimming, strain of bird and beak length. This method of beak-trimming is still overwhelmingly favoured in Industry and there appears to be no other alternative procedures that are more effective. Sharp secateurs have been used trim the upper beak of both layers and turkeys. Bleeding from the upper mandible ceases shortly after the operation, and despite the regrowth of the beak a reduction of cannibalism has been reported. Very few differences have been noted between behaviour and production of the hot blade and cold blade cut chickens. This method has not been used on a large scale in Industry. There are anecdotal reports of cannibalism outbreaks in birds with regrown beaks. A robotic beak-trimming machine was developed in France, which permitted simultaneous, automated beak-trimming and vaccination of day-old chicks of up to 4,500 chickens per hour. Use of the machine was not successful because if the chicks were not loaded correctly they could drop off the line, receive excessive beak-trimming or very light trimming. Robotic beak-trimming was not effective if there was a variation in the weight or size of chickens. Capsaicin can cause degeneration of sensory nerves in mammals and decreases the rate of beak regrowth by its action on the sensory nerves. Capsaicin is a cheap, non-toxic substance that can be readily applied at the time of less severe beak-trimming. It suffers the disadvantage of causing an extreme burning sensation in operators who come in contact with the substance during its application to the bird. Methods of applying the substance to minimise the risk to operators of coming in contact with capsaicin need to be explored. A method was reported which cuts the beaks with a laser beam in day-old chickens. No details were provided on the type of laser used, or the severity of beak-trimming, but by 16 weeks the beaks of laser trimmed birds resembled the untrimmed beaks, but without the bill tip. Feather pecking and cannibalism during the laying period were highest among the laser trimmed hens. Currently laser machines are available that are transportable and research to investigate the effectiveness of beak-trimming using ablasive and coagulative lasers used in human medicine should be explored. Liquid nitrogen was used to declaw emu toes but was not effective. There was regrowth of the claws and the time and cost involved in the procedure limit the potential of using this process to beak-trim birds.