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341.
为PC—1500袖珍计算机配备数据采集接口,可扩大其使用范围。本文详细介绍了PC—1500计算机15路带放大器的数据采集接口的设计情况,给出了电气原理图,并通过测试实例介绍了它的编程及使用方法。该接口的设计为农业机械或其它机械进行计算机测试提供了一种手段。  相似文献   
342.
为保证林地数据真实性、准确性和时效性,降低林地年度变更及森林图斑复位调查数据配发工作量,在2016年度林地变更调查成果和贵州省第四次森林资源普查成果基础上,利用ArcGIS建模技术和Python语言完成小班图形边界衔接、数据结构和代码之间的转换工作,实现了全省林地变更调查期初数据配发以及森林资源图斑复位调查数据配发,较常规数据处理方法效率有一定地提高,为其它数据之间的转换提供可借鉴的经验。  相似文献   
343.
A series of experiments were conducted in which label rate (0.3 g per kg of wheat) with diatomaceous earth (DE) formulation Protect-It. Exposure studies were carried out at two levels of relative humiditiy (40% and 55%), two levels of insect density (10 or 20 adults per vial), and three levels of exposure periods. Test insects were placed in vials containing 40 g of soft white winter wheat mixed with either 0 or 0.3 g Protect-It per kg of wheat. After relating exposure periods for both insect density and relative humidity levels, highest mortality was only 16%. Mortality, regardless of the dose rate applied (0 and 0.3 g) were not significantly increased as the exposure period increased. Regardless of relative humidity (r.h.) (40% and 55%r.h.), mortality in control were not significantly increased as the exposure period increased for the same insect density. However, significant differences among the three exposure periods in 10 adults’ density in 0.3 g DE application. Mortality was significantly increased in 10 adults’ density. In this case mortality of R. dominica adults increased with the increasing of the exposure intervals. As for 20 adults’ density, mortality in 0.3 g DE application was not significantly changed along with the exposure intervals. After insects were exposed for 1, 2, or 3 week, dead and live insects were removed, and the wheat in the vial were returned to relating humidity box and kept for 8 week until F1 adults emerged. Then, the number of F1 adult was counted. The mean numbers of F1 adults on untreated wheat at all density and r.h. combinations, regardless of exposure periods were significantly higher than that of 0.3 g DE- treated wheat (Fig. 3). At each density and treatment, the mean number of F1 adults at 55% r.h. were higher that that of 40%r.h. The comparison between adult densities at each r.h. and treatment showed that adult densities influenced the F1 production of R. dominica and F1 adults were always higher at 20 adults’ density. The mean number of F1 adults at each density, regardless of treatment progressively increased as the exposure period increased. Fewer progeny were produced at 10 adults’ density compared to 20 adults’ density for same exposure periods. The highest reproduction occurred in 3 week of exposure period for both insect densities. Regardless of adult densities, the mean number of F1 adults was significantly increased as the exposure period increased (Fig. 5) for both control and 0.3 g DE treatment. Reduction of F1 adults at 0.3 g DE application compared to control were found to be 76.88, 74.78 and 67.63% for 1, 2 and 3 week of exposure period, respectively.  相似文献   
344.
Real time quantitative PCR (qPCR) is one of the key technologies of the post-genome era, with clear advantages compared to normal end-point PCR. In this paper, we report the first qPCR-based assay for the identification of Fasciola spp. Based on sequences of the second internal transcribed spacers (ITS-2) of the ribosomal rRNA gene, we used a set of genus-specific primers for Fasciola ITS-2 amplification, and we designed species-specific internal TaqMan probes to identify F. hepatica and F. gigantica, as well as the hybrid 'intermediate'Fasciola. These primers and probes were used for the highly specific, sensitive, and simple identification of Fasciola species collected from different animal host from China, Spain, Niger and Egypt. The novel qPCR-based technique for the identification of Fasciola spp. may provide a useful tool for the epidemiological investigation of Fasciola infection, including their intermediate snail hosts.  相似文献   
345.
我们采用双峰驼的外周血液淋巴细胞培养方法,对其染色体进行了分析研究。研究结果表明,双峰驼的染色体数目为 2n=74。并初步摸索出一个比较易行的培养操作过程,为进一步开展骆驼遗传结构研究提供了参考材料.  相似文献   
346.
本文分析了4个苜蓿品种的产量表现、选择适宜种植的品种,提出苜蓿种植技术要点。  相似文献   
347.
348.
Two experiments were conducted to determine the effects of crude protein (CP) level in concentrate (experiment 1) and concentrate level (experiment 2) on feed intake, nutrient digestibility, nitrogen (N) retention, ruminal pH and NH3-N concentration and average daily gain (ADG) of Vietnamese local fattening cattle. Animals (24 cattle, initial live weight (LW) 150.3?±?11.8 kg in experiment 1 and 145.1?±?9.8 kg in experiment 2) were allotted based on LW to one of four treatments in a randomised complete block design. In experiment 1, concentrate with four levels of CP (10, 13, 16 and 19 %) was fed at 1.5 % of LW. In experiment 2, concentrate was fed at 1.0, 1.4, 1.8 and 2.2 % of LW. In both experiments, roughage was 5 kg/day native grass and ad libitum rice straw (fresh basis). Results showed that the CP level in concentrate significantly affected dry matter (DM) intake (P?<?0.05), N retention, ADG and ruminal NH3-N concentration (P?<?0.01), but it had no significant effect on DM, organic matter (OM) and neutral detergent fibre (NDF) digestibility (P?>?0.05), whereas CP digestibility increased (P?<?0.001) along with the CP level. DM intake, N retention and ADG increased (P?<?0.001) linearly with concentrate intake. DM and CP digestibility were not significantly affected by concentrate intake (P?>?0.05). OM digestibility and NH3-N concentration increased linearly (P?<?0.05), whereas NDF digestibility and ruminal pH declined linearly with increased concentrate consumption (P?<?0.01). These results indicate that 16 % CP in concentrate and feeding concentrate at the rate of 2.2 % of LW are recommendable for fattening local cattle in Vietnam.  相似文献   
349.
The in vivo test on the chorioallantoic membrane of the fertilized hen's egg (CAM assay) is a current method to determine antiangiogenic, antiinflammatory activity and toxic effects of individual compounds or complex plant extracts. The method is used for testing natural compounds in small amounts for revealing various modes of action and the complex mechanisms related to angiogenesis and inflammation. Furthermore, possible side effects such as membrane irritation, toxic, and anticoagulant properties of the investigated material in question can be detected. For the evaluation, the essential oil obtained by hydrodistillation of the aerial parts of Origanum onites L., a common spice and medicinal plant, was tested for its effect in the chorioallantoic membrane (CAM) assay. The essential oil composition was revealed by means of gas chromatography-mass spectrometry (GC-MS). Eighty three components were identified, representing 99.1% of the total oil. Carvacrol, thymol, p-cymene, and gamma-terpinene were found as major components and were also individually tested in the CAM assay. Along with the monoterpenes carvacrol and thymol, their methyl ether derivatives were also examined for comparison of their physiological action. Neither the essential oil nor its components showed any pronounced antiinflammatory or antiangiogenic property in the CAM assay, at 10-250 microg/pellet. However, the irritant effect of the essential oil was linked to thymol in a dose-response fashion, up to 10 microg/pellet, where it was still showing irritation.  相似文献   
350.
燕麦新品种介绍   总被引:1,自引:0,他引:1  
区农科院巴雪试验站,通过近几年的引种与试验,筛选出青引1号、青引2号和加拿大3号等品种适宜在白朗及类似区域种植。本文介绍了青引1号、青引2号和加拿大3号等品种的主要特征特性与栽培技术要点。  相似文献   
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