Effects of cryogenic treatment on the thermal physical properties of Cu_(76.12) Al_(23.88) alloy

The thermal diffusion coefficient, heat capacity, thermal conductivity, and thermal expansion coefficient of Cu76.12Al23.88 alloy before and after cryogenic treatment in the heating temperature range of 25℃ to 600℃ were measured by thermal constant tester and thermal expansion instrument. The effects of cryogenic treatment on the thermal physical properties of CU76,12A123,88 alloy were investigated by comparing the variation of the thermal parameters before and after cryogenic treatment. The results show that the variation trend of the thermal diffusion coefficient, heat capacity, thermal conductivity, and thermal expansion coefficient of CU76.12Al23.88 alloy after cryogenic treatment was the same as before. The cryogenic treatment can increase the thermal diffusion coefficient, thermal conductivity, and thermal expansion coeffi- cient of Cu76.12Al23.88 alloy and decrease its heat capacity. The maximum difference in the thermal diffusion coefficient between the before and after cryogenic treatment appeared at 400℃. Similarly, thermal conductivity was observed at 200℃.

Effects of Ultraviolet Radiation on Skeleton Development of Broiler Chickens

Seven hundred and twenty one-day-old AA broiler chickens were randomly allocated into two groups （male and female for half）, and put into two identical closed houses with different lighting programs. The first house was illuminated by using common incandescence light, and the second one was added with ultraviolet radiation light from the second week onwards. The birds lived in a floor with litters and free access to feed and water. Temperature, humidity and immune programs in the two houses were similar. The results showed that under ultraviolet radiation, the growth speed of skeleton increased （the shank length was significantly increased in the third week, P〈0.05; the leg muscle weight was significantly improved by 3.87%, P〈 0.05）; the skeleton quality improved （the density of skeleton mineralization was significantly increased by 6.11%, P 〈 0.01; serum calcium, phosphorus, and alkaline phosphatase activity were all improved）; and the growth performance was improved （feed conversion ratio was improved by 1.4% averagely; the uniformity of body weight, the shank length, the inclined body length and body height were significantly improved） in broiler chicken.

Construction and analysis of a plant transformation binary vector pBDGG harboring a bi-directional promoter fusing dual visible reporter genes

The constitutive promoter of cauliflower mosaic virus 35S （CaMV 35S） is a polar unidirectional promoter and is widely used in plant genetic engineering. In the present study, the unidirectional CaMV 35S promoter has been modified to a bi-directional promoter by fusing its minimal promoter element to the 5＇ end of CaMV 35S promoter in the opposite orientation. To qualitatively and quantitatively estimate its bi-directional transcriptional function and activity, two visible reporter genes, gusA （13-glucuronidase, GUS） and gfp （green fluorescent protein, GFP）, were fused to the two ends of the promoter in bi-orientations ending with NOS terminator sequences, respectively. Stable expression of gusA and gfp genes in transgenic tobacco （Nicotiana tabacum L.） was visulized by histochemically staining for GUS and fluorescence microscopic observation under UV for GFP in transgenic plants. The expression of two reporter genes showed that the constructed bi-directional promoter did have the bi-directional transcriptional function in both expected orientations. The quantitative estimation of GUS and GFP were determined on a HITACHI F1000 Fluorescence Spectrophotometer with various wavelengths of excitation and emission. The GUS activity varied from g to 250 pmol 4-MU/min/mg protein and the GFP content varied from 0.9 to 1.8 μg/ mg protein in various lines of transgenic tobacco plants. Higher GUS activity generally coupled with lower GFP content, and vice versa.

A new triterpene and a saponin from Centella asiatica

A new triterpene and a saponin, named 2α,3β23-trihydroxyurs-20-en-28-oic acid （1） and 2α,3β,23-trihydroxyurs-20-en-28-oic acid O-α-L-rhanmopyranosyl-（1→4）-O-β-D-glucopyranosyl-（1→6）-O-β-D-glucopyranosyl ester （2）, have been isolated from the aerial part of CenteUa asiatica. Their structures were elucidated by spectral methods, including 2D-NMR spectra.

Effects of different supplements on tetraploid black locust (Robinia pseudoacacia L.) silage

Preparation of silage is a common method to preserve green forage. It plays an important role in improving forage utilization, solving the problem of forage provision and meeting the nutritional needs of livestock in winter and spring. The effects of various supplements on tetraploid black locust （Robinia pseudoacacia L.） silage were studied by analyzing its color, odor, texture, pH value, the composition and amount of organic acids, the ammonia-N/total-N ratio, crude protein, neutral detergent fibers and acid detergent fibers. Our results show that the silage quality of wilted tetraploid R. pseudoacacia preserved alone is acceptable, while adding brown sugar and Yishengkang to tetraploid R. pseudoacacia foliage improved its quality. The treatments consisting of the tet- raploid R. pseudoacacia mixed with 33% and 50% corn stalk achieved the best silage quality in terms ofpH value （p 〈 0.01）, amount of lactic acid （p 〈 0.01）, the ammonia-N/total-N ratio （p 〈 0.01） and the fermentation quality. These treatments also resulted in a high content of crude protein and lower amounts of acid detergent fibers. The treatment consisting of the tetraploid R. pseudoacacia mixed with 20% corn stalk was also good in the quality of its fermentation.

NUMERICAL SIMULATION OF TEMPERATURE FIELD DURING MAGNETIC FIELD QUENCHING

Based on the theories of the heat transfer, the principle of phase transformation and the theory of electric and magnetic field, the mathematical model of transient temperature field involving phase transformation during magnetic field quenching is established. The heat exchange equation including magnetic field is founded. The finite element equation is set up. The distributing of transient temperature on the coupling effects of heat and magnetism is obtained. With test and measurement, the results show that after magnetic field quenching, cooling velocity is decreased, cooling curve is flatten out, and the hardness is slightly raised.

Influences of spin on the properties of a weak-coupled magnetopolaron in quantum dot

Considering the influences of the spin on the ground state energy,the properties of a weak-coupled magnetopolaron in quantum dots are studied by using a linear combination operator and unitary transformation method.The numerical calcu-lation results for CaP crystals have been given as examples.

Tectonic evolution and the analysis of unfavorable geology in a tunnel

Based on the theory of geomechanics and using geologic analytical methods,analyed the fault characteristics, mechanical properties, displacement mode, tectonic system, structural pattern, activity mode of stress, tectonic activity, and tectonic evolution ofthe area of the Xiamen submarine tunnel, the strike NWW 295^(。), which is the main unfavorable geological structure that affects the safety of the tunnel construction; the macrogeological prediction concludes that weathered troughs and groundwater-rich zonesformed by its larger-scale fault fracture zones are the main unfavorable geological bodiesprovides a basis for preventing the geo-logical hazards in the tunnel construction.

Physiological changes of leaves in response to cold in Phyllostachys propinqua

There are no previous records about planting bamboo in Changli, Hebei Province, north China. Since they were introduced in 2004, the propinquity bamboo （Phyllostachys propinqua McClure） has demonstrated good adaptability to the cold climate in Changli. The overwintering status of the bamboo and some of its physiological changes after the winter have been studied to ascer- tain the adaptability of the bamboo to the cold weather in Changli and to establish a firm basis for growing the plants in larger areas in northern China. The bamboo lived through the winter without any protection. The leaves of windward bamboos growing at various intervals have been studied for their viability and health after the winter. The changes in some physiological indices of the leaves were measured in the following spring. Results showed that the bamboo is partly green even at a temperature as low as -22.3℃ in Changli. During the winter, some leaves died and some partly died. Leaves are light in color and turn gradually to a dark green when the temperature increases in the following spring. As new leaves develop, the contents of chlorophyll and water and the ratio of fi＇ee and bound water in the old leaves increase as does transpiration. At the same time the contents of free amino acid, proline, soluble sugar, malondialdehede （MDA）, permeability of the membrane, superoxide dismutase （SOD） and peroxidase （POD） activities de- crease. The direction of these physiological indices changes when the new leaves begin to sprout. The old leaves reduce their rate of photosynthesis, their blade functions decline gradually and the leaves fall off towards the middle of June. The cold wind affects the survival of bamboo leaves in winter, but has little effect on new leaves growing at the start of the following year. The results indicate that the propinquity bamboo can survive the winter in Changli quite well.

Effect of Chinese Herbal Medicine on Immunohistochemistry of Harder's Glands of Chickens

To investigate the mechanism of action of Chinese herbal medicine, the immunocells of Harder＇s glands were observed. The healthy Hy-Line Brown chickens of 12-day-old were divided into three groups randomly. The chickens in group 1 and 2 drank the water with 0.5% and 1% Chinese herbal medicine immunopromoter every day. The chickens in group 3 as control drank pure water. The Harder＇s glands of the chickens from 0.5% group, 1% group and control group at 24, 36 and 48 d after drinking medicine respectively were made into histological section. And then the histological sections were observed histologically. The results showed that Chinese herbal medicine could increase the quantity of the immunocells in glandular organs conspicuously. Immunopotentiator of Chinese herbal medicine could promote the amount and growth of secreted immunoglobuline and elevate the immune level of the orgamsm, and the effect of 1% group was higher than that of 0.5% group.

Error Analysis and Its Offset on the NC Lathe Machine in Cutting a Semi-Sphere Surface

This paper analyzed the errors that occurred by leaving the shape of the cutting edge out of consideration on a NC lathe machine in cutting a semi-sphere surface and brought forward a method to offset these errors and the correct calculated formula for some parameters on the basis of experiments. It has increased the manufacturing accuracy of the semi-sphere surface on the NC lathe machine.

Temperature rise and flow of Zr-based bulk metallic glasses under high shearing stress

Deformation of the bulk metallic glasses (BMGs) and the creation and propagation of the shear bands are closely interconnected.Shearing force was loaded on Zr 41.2 Ti 13.8 Cu 12.5 Ni 10.0 Be 22.5 (Vit.1) BMGs by cutting during the turning of the BMG rod.The temperature rise of alloy on the shear bands was calculated and the result showed that it could reach the temperature of the super-cooled liquid zone or exceed the melting point.The temperature rise caused viscous fluid flow and brought about the deformation of BMGs.This suggested that the deformation of BMGs was derived,at least to some extent,from the adiabatic shear temperature rise.