Effect of UV - B radiation on the feeding behaviour of marine zooplankton is important to assessing the health harm of marine ecosystem due to the gradually enhanced UV - B radiation in air. However, there are a few s...Effect of UV - B radiation on the feeding behaviour of marine zooplankton is important to assessing the health harm of marine ecosystem due to the gradually enhanced UV - B radiation in air. However, there are a few studies on this topic. The feeding behavior of the rotifer, Brachionus plicatilis, under the treatment of UV - B radiation on five species of microalgae, i. e. , Chlorella sp. , Tetraselmis chuii, Isochrysis galbana Park 8701, Chaetoceros muelleri Lermumerman, and Nitzschia clostertum, was studied. The results showed that the filtering and feeding rates of the rotifer decreased significantly with the dose increase of UV - B radiation when fed with five species of microalgae respectively （ P 〈 0.05 ） which indicates UV - B radiation inhibits the feeding activities of the rotifer on microalage. The mixed culture experiments shows the rotifer preferred to feed Chlorella sp. , then C. muelleri, L galbana, N. clostertum and T. chuii in turn if without UV - B radiation. Under the highest dose of UV - B radiation treatment （2.70 kJ/m^2）, the rotifer preferred to feed C. muelleri, then Chlorella sp. , N. clostertum, L galbana and T. chuii in turn. Chlorella sp. , L galbana and C. muelleri became the more favorite foods of the rotifer while T. chuii and N. clostertum became less favorite foods. The change of feeding rate and feeding selectivity of zooplankton driven by the enhanced UV - B radiation will lead to the change in the structure of phytoplankton community.展开更多
Based on the structure of chute - feed and autoleveHer, an analysis of their working principle and the verification of their practical production results have been carried out. Finally, the future investigation direet...Based on the structure of chute - feed and autoleveHer, an analysis of their working principle and the verification of their practical production results have been carried out. Finally, the future investigation direetiom of chute - feed and card autuleveller are put forward.展开更多
Properties of enzyme production of a Bacillus subtitles strain （ MSJ-5 ） isolated from soil were studied in the test. Enzyme production reached the peak when MSJ-5 being cultured in fermentation medium for 32 h. 6-1...Properties of enzyme production of a Bacillus subtitles strain （ MSJ-5 ） isolated from soil were studied in the test. Enzyme production reached the peak when MSJ-5 being cultured in fermentation medium for 32 h. 6-1,4-D-mannanase was the main component of crude enzyme solution, test results showed that the optimal reaction temperature of the enzyme was 50 ℃, the optimum reaction pH was 7.0, and the enzyme was stable when pH was 5.0 -7.0. Hydrolysis test re- suits showed that β-1,4-D-mannanase produced by MSJ-5 had significant viscosity reduction effects on Konjak mannan, and the major hydrolysis product was man- nan oligosaecharide. The results indicated that 6-1,4-D-mannanase produced by B. subtilis MSJ-5 had application potential in feed ingredients and functional oligo- saccharides industry.展开更多
Herbicide tolerant plants such as Roundup-Ready soybean contain residues of glyphosate herbicide. These residues are considered safe and previous animal-feeding-studies have failed to find negative effects related to ...Herbicide tolerant plants such as Roundup-Ready soybean contain residues of glyphosate herbicide. These residues are considered safe and previous animal-feeding-studies have failed to find negative effects related to such chemical residues. The present study tests 8 experimental soy- meal diets as feed in groups (each containing 20 individuals) of test-animals (D. magna). The diets have different levels of glyphosate residues and we show that animal growth, reproductive maturity and number of offspring are correlated with these chemicals. The tested soybeans are from ordinary agriculture in Iowa USA and the residues are below the regulatory limits. Despite this, clear negative effects are seen in life-long feeding. The work enhances the need for including analysis of herbicide residues in future assessment of GMO.展开更多
This study was carried out in 2022 at the Itato agriculture community estate of fish hatchery in eastern Senegal with the aim of finding an alternative method to 17-α-methyl testosterone (MT) by using Garcinia kola ...This study was carried out in 2022 at the Itato agriculture community estate of fish hatchery in eastern Senegal with the aim of finding an alternative method to 17-α-methyl testosterone (MT) by using Garcinia kola “Bitter kola” powder to obtain Oreochromis niloticus male sex populations. 1800 fry of average size between 0.01 and 0.02 g were distributed in 12 aboveground tanks of 1 m3 each at a rate of 150 individuals/tank, following 6 duplicate treatments. The negative (B1 and B2) and positive (B3 and B4) control diets, to which between 0 and 60 mg/kg of 17alpha-methyl testosterone had been added respectively, were mixed with industrial feed containing 40% protein;the tank diets (B5 and B6), (B7 and B8), (B9 and B10) and (B11 and B12) contained 10 g, 20 g, 30 g and 40 g of Garcinia kola powder respectively for 1 kg of industrial feed con-taining 40% protein. These different treatments resulted in high proportions of males in the order of 97.03%;98.09% for the hormone and proportions of 94.03%;93.26% for 20 g of Garcinia kola extracts. In terms of weight growth, the best average weights for the hormone and Garcinia kola were 0.896 g and 0.980 g respectively. With regard to fish survival, the following results were recorded: 95.53% and 94.56% respectively for additions of 20 g and 30 g of Garcinia kola extracts to the feed supplied to the fish. On the other hand, a significant difference in the mortality rate of 35% and 5% respectively for the conventional hormone and 20 g of Garcinia kola extracts was observed. To conclude the study, it is recommended that further studies be carried out to determine the quality of the flesh, their life stages and the profile of the amino acids present in their proteins.展开更多
A new theory and method that differs from the tradition-al single plated weft - knitting theory and method hasbeen expounded after theoretical analyzing and experi-mental proving. If the new method is used when platin...A new theory and method that differs from the tradition-al single plated weft - knitting theory and method hasbeen expounded after theoretical analyzing and experi-mental proving. If the new method is used when platingstitch is knitted on large diameter weft knitting machine,the thorny problem of long standing that ground yarn iseasy to appear on the face side of fabric is solved. Thenew method, i.e, the production of physical ability oftraining uniform for serviceman has been used.展开更多
The existing plastic forming equipment are mostly driven by traditional AC motors with long trans- mission chains, low efficiency, large size, low precision and poor dynamic response are the common disadvantages. In o...The existing plastic forming equipment are mostly driven by traditional AC motors with long trans- mission chains, low efficiency, large size, low precision and poor dynamic response are the common disadvantages. In order to realize high performance forming processes, the driving device should be improved, especially for com- plicated processing motions. Based on electric servo direct drive technology, a novel AC servo rotating and linear composite driving device is proposed, which features implementing both spindle rotation and feed motion with- out transmission, so that compact structure and precise control can be achieved. Flux switching topology is employed in the rotating drive component for strong robustness, and fractional slot is employed in the linear direct drive component for large force capability. Then the mechanical structure for compositing rotation and linear motion is designed. A device prototype is manufactured, machining of each component and the whole assembly are presented respectively. Commercial servo amplifiers are utilized to construct the control system of the proposed device. To validate the effectiveness of the proposed composite driving device, experimental study on thedynamic test benches are conducted. The results indicate that the output torque can attain to 420 N-m and the dynamic tracking errors are less than about 0.3 rad in the rotating drive, the dynamic tracking errors are less than about 1.6 mm in the linear feed. The proposed research provides a method to construct high efficiency and accu- racy direct driving device in plastic forming equipment.展开更多
5-（Difluoromethoxy）-2-mercapto- 1H-benzimi- dazole （DMB） was precipitated by adding acetic acid to the DMB sodium salt solution. The spherical agglomeration of DMB during the reactive crystallization in a batch cr...5-（Difluoromethoxy）-2-mercapto- 1H-benzimi- dazole （DMB） was precipitated by adding acetic acid to the DMB sodium salt solution. The spherical agglomeration of DMB during the reactive crystallization in a batch crystallizer was monitored by real-time Particle Video Microscope （PVM）. We found that the low feeding rate of acetic acid, high crystallization temperature, low agitation rate or adding seed crystal can facilitate the formation of spherical agglomerates. By using a simple model, the mean crystal agglomerate size of DMB thus predicted is generally in agreement with the experimental data. In addition, the crystallization process of DMB was optimized by a new control strategy of supersaturation to avoid disadvantages brought by agglomeration.展开更多
基金This work was supported by the National Natural Science Foundation of China under contract Nos 30270258 and 40506028 the National High Technology Research and Development Program of China under contract No. 2002AA648010+2 种基金 the China Postdoctoral Science Foundation under contract No. 2005037237 the Shandong Scientific Research Encouragement Foundation for Talent Youths under contract No. 03BS120the Doctor Scientific Research Foundation of Dongying Vocational College under contract No. B J0602.
文摘Effect of UV - B radiation on the feeding behaviour of marine zooplankton is important to assessing the health harm of marine ecosystem due to the gradually enhanced UV - B radiation in air. However, there are a few studies on this topic. The feeding behavior of the rotifer, Brachionus plicatilis, under the treatment of UV - B radiation on five species of microalgae, i. e. , Chlorella sp. , Tetraselmis chuii, Isochrysis galbana Park 8701, Chaetoceros muelleri Lermumerman, and Nitzschia clostertum, was studied. The results showed that the filtering and feeding rates of the rotifer decreased significantly with the dose increase of UV - B radiation when fed with five species of microalgae respectively （ P 〈 0.05 ） which indicates UV - B radiation inhibits the feeding activities of the rotifer on microalage. The mixed culture experiments shows the rotifer preferred to feed Chlorella sp. , then C. muelleri, L galbana, N. clostertum and T. chuii in turn if without UV - B radiation. Under the highest dose of UV - B radiation treatment （2.70 kJ/m^2）, the rotifer preferred to feed C. muelleri, then Chlorella sp. , N. clostertum, L galbana and T. chuii in turn. Chlorella sp. , L galbana and C. muelleri became the more favorite foods of the rotifer while T. chuii and N. clostertum became less favorite foods. The change of feeding rate and feeding selectivity of zooplankton driven by the enhanced UV - B radiation will lead to the change in the structure of phytoplankton community.
文摘Based on the structure of chute - feed and autoleveHer, an analysis of their working principle and the verification of their practical production results have been carried out. Finally, the future investigation direetiom of chute - feed and card autuleveller are put forward.
基金Supported by National Public Welfare Industry(Agriculture)Scientific Special Project(201203001)Shandong Agricultural Sciences Youth Fund Project(2014QNM21)Shandong Independent Innovation Achievements Special(2013ZHZX2A0402)
文摘Properties of enzyme production of a Bacillus subtitles strain （ MSJ-5 ） isolated from soil were studied in the test. Enzyme production reached the peak when MSJ-5 being cultured in fermentation medium for 32 h. 6-1,4-D-mannanase was the main component of crude enzyme solution, test results showed that the optimal reaction temperature of the enzyme was 50 ℃, the optimum reaction pH was 7.0, and the enzyme was stable when pH was 5.0 -7.0. Hydrolysis test re- suits showed that β-1,4-D-mannanase produced by MSJ-5 had significant viscosity reduction effects on Konjak mannan, and the major hydrolysis product was man- nan oligosaecharide. The results indicated that 6-1,4-D-mannanase produced by B. subtilis MSJ-5 had application potential in feed ingredients and functional oligo- saccharides industry.
文摘Herbicide tolerant plants such as Roundup-Ready soybean contain residues of glyphosate herbicide. These residues are considered safe and previous animal-feeding-studies have failed to find negative effects related to such chemical residues. The present study tests 8 experimental soy- meal diets as feed in groups (each containing 20 individuals) of test-animals (D. magna). The diets have different levels of glyphosate residues and we show that animal growth, reproductive maturity and number of offspring are correlated with these chemicals. The tested soybeans are from ordinary agriculture in Iowa USA and the residues are below the regulatory limits. Despite this, clear negative effects are seen in life-long feeding. The work enhances the need for including analysis of herbicide residues in future assessment of GMO.
文摘This study was carried out in 2022 at the Itato agriculture community estate of fish hatchery in eastern Senegal with the aim of finding an alternative method to 17-α-methyl testosterone (MT) by using Garcinia kola “Bitter kola” powder to obtain Oreochromis niloticus male sex populations. 1800 fry of average size between 0.01 and 0.02 g were distributed in 12 aboveground tanks of 1 m3 each at a rate of 150 individuals/tank, following 6 duplicate treatments. The negative (B1 and B2) and positive (B3 and B4) control diets, to which between 0 and 60 mg/kg of 17alpha-methyl testosterone had been added respectively, were mixed with industrial feed containing 40% protein;the tank diets (B5 and B6), (B7 and B8), (B9 and B10) and (B11 and B12) contained 10 g, 20 g, 30 g and 40 g of Garcinia kola powder respectively for 1 kg of industrial feed con-taining 40% protein. These different treatments resulted in high proportions of males in the order of 97.03%;98.09% for the hormone and proportions of 94.03%;93.26% for 20 g of Garcinia kola extracts. In terms of weight growth, the best average weights for the hormone and Garcinia kola were 0.896 g and 0.980 g respectively. With regard to fish survival, the following results were recorded: 95.53% and 94.56% respectively for additions of 20 g and 30 g of Garcinia kola extracts to the feed supplied to the fish. On the other hand, a significant difference in the mortality rate of 35% and 5% respectively for the conventional hormone and 20 g of Garcinia kola extracts was observed. To conclude the study, it is recommended that further studies be carried out to determine the quality of the flesh, their life stages and the profile of the amino acids present in their proteins.
文摘A new theory and method that differs from the tradition-al single plated weft - knitting theory and method hasbeen expounded after theoretical analyzing and experi-mental proving. If the new method is used when platingstitch is knitted on large diameter weft knitting machine,the thorny problem of long standing that ground yarn iseasy to appear on the face side of fabric is solved. Thenew method, i.e, the production of physical ability oftraining uniform for serviceman has been used.
基金Supported by National Natural Science Foundation of China(Grant No.51335009)Major National Science and Technology Project of China(Grant No.2011ZX04001-011)
文摘The existing plastic forming equipment are mostly driven by traditional AC motors with long trans- mission chains, low efficiency, large size, low precision and poor dynamic response are the common disadvantages. In order to realize high performance forming processes, the driving device should be improved, especially for com- plicated processing motions. Based on electric servo direct drive technology, a novel AC servo rotating and linear composite driving device is proposed, which features implementing both spindle rotation and feed motion with- out transmission, so that compact structure and precise control can be achieved. Flux switching topology is employed in the rotating drive component for strong robustness, and fractional slot is employed in the linear direct drive component for large force capability. Then the mechanical structure for compositing rotation and linear motion is designed. A device prototype is manufactured, machining of each component and the whole assembly are presented respectively. Commercial servo amplifiers are utilized to construct the control system of the proposed device. To validate the effectiveness of the proposed composite driving device, experimental study on thedynamic test benches are conducted. The results indicate that the output torque can attain to 420 N-m and the dynamic tracking errors are less than about 0.3 rad in the rotating drive, the dynamic tracking errors are less than about 1.6 mm in the linear feed. The proposed research provides a method to construct high efficiency and accu- racy direct driving device in plastic forming equipment.
文摘5-（Difluoromethoxy）-2-mercapto- 1H-benzimi- dazole （DMB） was precipitated by adding acetic acid to the DMB sodium salt solution. The spherical agglomeration of DMB during the reactive crystallization in a batch crystallizer was monitored by real-time Particle Video Microscope （PVM）. We found that the low feeding rate of acetic acid, high crystallization temperature, low agitation rate or adding seed crystal can facilitate the formation of spherical agglomerates. By using a simple model, the mean crystal agglomerate size of DMB thus predicted is generally in agreement with the experimental data. In addition, the crystallization process of DMB was optimized by a new control strategy of supersaturation to avoid disadvantages brought by agglomeration.
