Drawing up of syllabus plays a very important role in directing college English teaching. With the fast developing pace of the situation and the increasing requirements for undergraduates＇ English level, the availabl...Drawing up of syllabus plays a very important role in directing college English teaching. With the fast developing pace of the situation and the increasing requirements for undergraduates＇ English level, the available Syllabus is obviously far from satisfaction. This paper, from six perspectives, expounds the inadequacies and drawbacks of the Syllabus. It points out that college English teaching and the Syllabus need reform and should keep pace with the times.展开更多
In this work, the effect of various effective dimensionless numbers and moisture contents on initiation of instability in combustion of moisty organic dust is calculated. To have reliable model, effect of thermal radi...In this work, the effect of various effective dimensionless numbers and moisture contents on initiation of instability in combustion of moisty organic dust is calculated. To have reliable model, effect of thermal radiation is taken into account. One- dimensional flame structure is divided into three zones： preheat zone, reaction zone and post-flame zone. To investigate pulsating characteristics of flame, governing equations are rewritten in dimensionless space-time （（, r/, ~） coordinates. By solving these newly achieved governing equations and combining them, which is completely discussed in body of article, a new expression is obtained. By solving this equation, it is possible to predict initiation of instability in organic dust flame. According to the obtained results by increasing Lewis number, threshold of instability happens sooner. On the other hand, pulsating is postponed by increasing Damk6hler number, pyrolysis temperature or moisture content. Also, by considering thermal radiation effect, burning velocity predicted by our model is closer to experimental results.展开更多
The growth, reproductive properties and the variations in total lipids and fatty acids in the gonads and muscle tissue of the mantis shrimp Squilla mantis （Crustacea： Stomatopoda） caught from the gulf of Gabes in T...The growth, reproductive properties and the variations in total lipids and fatty acids in the gonads and muscle tissue of the mantis shrimp Squilla mantis （Crustacea： Stomatopoda） caught from the gulf of Gabes in Tunisia were studied by sampling carried out between Jan. 2005 and Dec. 2006 to elucidate the importance of these components during sexual maturation. A total of 16,569 specimens were examined. The sex of this species was determined macroscopically and the proportion of females （47.07%） was significantly lower than that of males （52.93%） with a ratio of 1 ：l. 12 （male^female）. The mean total lengths （TL） of the male and female individuals were 142.02 ~： 22.76 mm and 141.45 ＋ 24.37 mm, respectively. Length-weight （TL-W） relationship was estimated as W = 7 ~ l06 TL3 o644 for females and W = 4 ~ 10＂6 TL320o7 for males, being altometrically positive for both sexes. The reproductive season, evaluated from the gonado-somatic index （GS1）, extended from Dec. to July, with a peak in Feb.. The smallest mature female was 93 mm total length. Fifty percent of the females were mature at 147.19 mm total length. The levels of lipid displayed pronounced seasonal fluctuations with the highest value in Feb. and the lowest value in Oct.. Major fatty acids in both gonads and muscle tissue （female and male） were C 14：0, C 16：0, C 18：0, C 18： I n-9, C 18：2n-6, C 18：3n-3, C20：4n-6, C20：5n-3 and C22：6n-3. Significant increases in the levels of saturated and poly-unsaturated fatty acids were observed in gonads. The levels of n-3 poly-unsaturated fatty acids （PUFA）, particularly C20：5n-3, decreased in gonads as ovarian development proceeded. Docosahexaenoic acid （DHA）, linoleic acid （LA） and eicosapentaenoic acid （EPA） were the most abundant polyunsaturated fatty acids （PUFAs） in the muscle tissue for both male and female. The highest percentages for EPA and DHA were found in winter and summer season for Squilla mantis in the Gulf of Gabes. The n-3/n-6 ratio fatty acids ratio in Squilla mantis can be significantly influenced by spawning and season. It was conchtded that the mantis shrimp is a healthy item in the human diet during the winter and summer period when balanced n-3/n-6 ratios and EPA and DHA levels are considered.展开更多
The approximate analytical solution of velocity is presented for incompressible and viscous fluid driven by the oscillation of the periodic pressure, between two slit parallel plates with corrugated walls by employing...The approximate analytical solution of velocity is presented for incompressible and viscous fluid driven by the oscillation of the periodic pressure, between two slit parallel plates with corrugated walls by employing perturbation method. The corrugations of the two walls are described as periodic sinusoidal waves with small amplitude either in phase or half-period out of phase. Based on the analysis, we discuss the influence of the dimensionless parameters on velocity u±and mean velocity parameter φ±numerically, such as Reynolds number Re, nondimensional amplitude A of pressure gradient and wave number k.展开更多
文摘Drawing up of syllabus plays a very important role in directing college English teaching. With the fast developing pace of the situation and the increasing requirements for undergraduates＇ English level, the available Syllabus is obviously far from satisfaction. This paper, from six perspectives, expounds the inadequacies and drawbacks of the Syllabus. It points out that college English teaching and the Syllabus need reform and should keep pace with the times.
文摘In this work, the effect of various effective dimensionless numbers and moisture contents on initiation of instability in combustion of moisty organic dust is calculated. To have reliable model, effect of thermal radiation is taken into account. One- dimensional flame structure is divided into three zones： preheat zone, reaction zone and post-flame zone. To investigate pulsating characteristics of flame, governing equations are rewritten in dimensionless space-time （（, r/, ~） coordinates. By solving these newly achieved governing equations and combining them, which is completely discussed in body of article, a new expression is obtained. By solving this equation, it is possible to predict initiation of instability in organic dust flame. According to the obtained results by increasing Lewis number, threshold of instability happens sooner. On the other hand, pulsating is postponed by increasing Damk6hler number, pyrolysis temperature or moisture content. Also, by considering thermal radiation effect, burning velocity predicted by our model is closer to experimental results.
文摘The growth, reproductive properties and the variations in total lipids and fatty acids in the gonads and muscle tissue of the mantis shrimp Squilla mantis （Crustacea： Stomatopoda） caught from the gulf of Gabes in Tunisia were studied by sampling carried out between Jan. 2005 and Dec. 2006 to elucidate the importance of these components during sexual maturation. A total of 16,569 specimens were examined. The sex of this species was determined macroscopically and the proportion of females （47.07%） was significantly lower than that of males （52.93%） with a ratio of 1 ：l. 12 （male^female）. The mean total lengths （TL） of the male and female individuals were 142.02 ~： 22.76 mm and 141.45 ＋ 24.37 mm, respectively. Length-weight （TL-W） relationship was estimated as W = 7 ~ l06 TL3 o644 for females and W = 4 ~ 10＂6 TL320o7 for males, being altometrically positive for both sexes. The reproductive season, evaluated from the gonado-somatic index （GS1）, extended from Dec. to July, with a peak in Feb.. The smallest mature female was 93 mm total length. Fifty percent of the females were mature at 147.19 mm total length. The levels of lipid displayed pronounced seasonal fluctuations with the highest value in Feb. and the lowest value in Oct.. Major fatty acids in both gonads and muscle tissue （female and male） were C 14：0, C 16：0, C 18：0, C 18： I n-9, C 18：2n-6, C 18：3n-3, C20：4n-6, C20：5n-3 and C22：6n-3. Significant increases in the levels of saturated and poly-unsaturated fatty acids were observed in gonads. The levels of n-3 poly-unsaturated fatty acids （PUFA）, particularly C20：5n-3, decreased in gonads as ovarian development proceeded. Docosahexaenoic acid （DHA）, linoleic acid （LA） and eicosapentaenoic acid （EPA） were the most abundant polyunsaturated fatty acids （PUFAs） in the muscle tissue for both male and female. The highest percentages for EPA and DHA were found in winter and summer season for Squilla mantis in the Gulf of Gabes. The n-3/n-6 ratio fatty acids ratio in Squilla mantis can be significantly influenced by spawning and season. It was conchtded that the mantis shrimp is a healthy item in the human diet during the winter and summer period when balanced n-3/n-6 ratios and EPA and DHA levels are considered.
基金Supported by the National Natural Science Foundation of China under Grant No.11472140the Natural Science Foundation of Inner Mongolia Autonomous Region of China under Grant No.2016MS0106the Inner Mongolia Grassland Talent under Grant No.12000-12102013
文摘The approximate analytical solution of velocity is presented for incompressible and viscous fluid driven by the oscillation of the periodic pressure, between two slit parallel plates with corrugated walls by employing perturbation method. The corrugations of the two walls are described as periodic sinusoidal waves with small amplitude either in phase or half-period out of phase. Based on the analysis, we discuss the influence of the dimensionless parameters on velocity u±and mean velocity parameter φ±numerically, such as Reynolds number Re, nondimensional amplitude A of pressure gradient and wave number k.
