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111.
大学英语网络教学改革状况调查   总被引:1,自引:0,他引:1  
通过调查问卷和访谈,调查学生对大学英语网络教学改革模式的看法及学生在新模式下的学习情况。调查结果发现,学生对英语网络教学持肯定的态度,但学生利用网络进行英语学习的情况仍差强人意,学生的自主学习意识及能力急需加强和提高  相似文献   
112.
动物岩画是内蒙古地区古代动物的图解,通过岩画中的动物群落结构对比,可以推测相同地域范围内,不同时期的动物分布情况,进而推断当地的自然环境变迁的过程。  相似文献   
113.
安定明 《安徽农业科学》2010,38(14):7479-7480
在分析坝上地区生态环境现状的基础上,对坝上地区风力发电的优势进行了相关研究,并提出了开发风电的思路。  相似文献   
114.
本文探讨了生态文化旅游定位,和在生态旅游与渗透生态文化教育相结合的问题。并从生态文化基础设施建设和挖掘生态文化内涵等方面阐述了龙湖山国家森林公园的规划方法,并提出了森林公园生态文化建设规划原则,规划重点和布局等内容。  相似文献   
115.
论网络环境下图书馆采编人员的素质建设   总被引:1,自引:0,他引:1  
文献采集是图书馆工作的起点,文献采编人员整体素质的高低直接影响到馆藏文献采集的方针、原则、计划和标准的理解能力和文献采集质量的优劣。论述了网络环境下,采编人员应具备的七大能力,分析了目前采编队伍存在的问题,并探讨了加强采编队伍建设的几项措施。  相似文献   
116.
酸化剂可以提高动物的生产性能,改善胃环境,文章从两个方面综述了酸化剂改善动物胃肠道内环境机理的研究,并对酸化剂未来的研究方向做了展望.  相似文献   
117.
袁应泽  李金辉 《中国农业气象》2005,26(2):136-138,141
通过对汉中盆地现有茶区生态气候状况的分析及与同纬度东部平原茶区比较,找出了汉中茶区生态气候和品质的比较优势与存在问题,提出:在退耕还茶中宜建生态茶园;生态园、老茶园和林区应根据局地小气候条件合理布局交错种植;宜推广无性繁殖和无污染管理技术。  相似文献   
118.
Effect of extended storage on egg quality, embryo mortality and hatchability in FUNAAB-ɑ chickens was determined. Hatchable eggs (n = 288; weighing 53.2 ± 4.67 g) collected from a flock of FUNAAB-ɑ layer breeder hens aged 32 weeks were stored in egg tray with broad end up under 16 ± 1.5°C for either 0, 4, 8, 12, 16 or 20 d. Before incubation, eight eggs from each group were evaluated for internal and external quality traits. Remaining eggs were set in an incubator and transferred into hatcher on embryonic day 18. Data collected were subjected to one-way analysis of variance. Egg weight loss (EWL; p < .001), surface area (p < .001), yolk diameter (p < .001), inner and outer blastoderm diameters (p < .05) and dead in germ (DIG; p < .001) increased with storage duration while yolk height (p < .001), yolk index (p < .001), albumen weight (p < .05), albumen height (p < .05), albumen index (p < .01), Haugh's unit (HU; p < .05), fertility (p < .001), hatchability of set (HATCHS; p < .001) and fertile eggs (p < .05) decreased. Weight losses of 0, 1.2, 2.2, 3.4, 4.6 and 6.1% were recorded in egg stored for 0, 4, 8, 12, 16 and 20 days respectively. Eggs stored beyond 8 days exhibited higher DIG and lower HATCHS. Shell percentage in 4 days storage (11.4%) was lower (p < .05) than in 16 days storage (13.4%). Shell thickness was similar in eggs stored for 0 to 12 days, but 8 days storage (0.60 mm) had thinner (p < .01) shell than day 16 (0.71 mm) and day 20 (0.73 mm) storage. Internal quality unit (IQU) was higher (p < .05) in fresh eggs (180.4) than in 12 days (167.8) and 20 days (167.8) stored eggs. Extended storage of FUNAAB-ɑ eggs caused EWL, surface area shrinkage, lowered HU and IQU, loss of yolk and albumen quality, increased blastoderm diameters and DIG, and decreased egg fertility and HATCHS from day 8 forward. Storing FUNAAB-ɑ eggs beyond 8 days reduced quality parameters; therefore, other mitigating factors are recommended when storing beyond 8 days.  相似文献   
119.
Behavioral and physiological traits of ectotherms are especially sensitive to fluctuations of environmental temperature. In particular, niche-specialist lizards are dependent on their physiological plasticity to adjust to changing environmental conditions. Lizards of the genus Phymaturus are viviparous, mainly herbivorous, and inhabit only rock promontories in the steppe environments of Patagonia and the Andes. Herein, we examine the vulnerability of the southernmost Phymaturus species to global warming: the endemic Phymaturus calcogaster, which lives in a mesic environment in eastern Patagonia. We studied body temperatures in the field (Tb), preferred body temperatures in a thermogradient (Tpref), the operative (Te) and environmental temperatures, and the dependence of running performance on body temperature. P. calcogaster had a mean Tb (27.04°C) and a mean Te (31.15°C) both lower than their preferred temperature (Tpref = 36.61°C) and the optimal temperature for running performance (To = 37.13°C). Lizard activity seems to be restraint during the early afternoon due high environmental temperatures. However, both, the high safety margin and warming tolerance suggest that the expected increase in environmental temperatures due to global warming (IPCC report in 2018) would not threaten, but indeed enhance locomotor performance in this population.  相似文献   
120.
The present objective of the study was to investigate the effect of fans cooling on dairy cow in northern mountainous region of Hebei in summer.Two cowsheds with the same structure and feeding technics were used to investigate the effect of fans on indoor temperature and humidity, physiological parameters and milking performance of dairy cow.The results showed that the average ambient temperature in cowshed with fans was 1.5℃ lower than that of the control cowshed, and the average wind velocity was 0.49 m/s higher than that of the control cowshed, reaching to 0.66 m/s.Temperature-humidity index (THI) of cowshed with fans was significantly lower than that of the control shed during the period of fans running (P<0.05).Besides, the rectal temperature and respiration rate of dairy cows in cowshed with fans were significantly lower than of the control cowshed (P<0.05), and the milk yield per cow per day was 17.0% higher than that of the control cowshed (P<0.05), however, the milk fat, milk protein and milk sugar were no significant difference from the control (P>0.05).Overall, fans could decrease indoor environment, moderate heat stress and increase performance and health of dairy cows in northern mountainous region of Hebei.  相似文献   
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