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101.
三自由度并联机构位置和运动分析及仿真   总被引:5,自引:6,他引:5  
分析了一种两平移一转动三自由度并联机构,得到该机构位置正反解析解,采用求导法得到其一阶和二阶运动影响系数。利用运动影响系数对该机构进行了速度和加速度分析,并在ADAMS软件上进行仿真,验证了该理论分析的正确性。同时,提供了该机构在中医推拿方面的具体应用实例。  相似文献   
102.
Recent investigations on the bitterness of coffee as well as 5- O-caffeoyl quinic acid roasting mixtures indicated the existence of another, yet unknown, bitter lactone besides the previously identified bitter compounds 5- O-caffeoyl- muco-gamma-quinide, 3- O-caffeoyl-gamma-quinide, 4- O-caffeoyl- muco-gamma-quinide, 5- O-caffeoyl- epi-delta-quinide, and 4- O-caffeoyl-gamma-quinide. In the present study, this orphan bitter lactone was isolated from the reaction products generated by dry heating of 5- O-caffeoylquinic acid model, and its structure was determined as the previously unreported 3- O-caffeoyl- epi-gamma-quinide by means of liquid chromatography-mass spectrometry (LC-MS) and one-/two-dimensional NMR experiments. The occurrence of this bitter lactone, exhibiting a low bitter recognition threshold of 58 micromol/L, in coffee beverages could be confirmed by LC-MS/MS (negative electrospray ionization) operating in the multiple reaction monitoring mode.  相似文献   
103.
【目的】利用FISH技术追踪三倍体‘银中杨’小孢子母细胞减数分裂过程特定染色体的行为,明确其配对和分离规律,丰富对杨树异源三倍体减数分裂过程染色体行为的细胞遗传学认识。【方法】以三倍体‘银中杨’花药为材料,对不同酶液组合和酶解时间进行筛选,在此基础上均进行减数分裂染色体制片,以45S rDNA序列为探针,利用FISH技术,对‘银中杨’小孢子母细胞减数分裂过程染色体行为进行追踪和分析。【结果】1)筛选出适于‘银中杨’小孢子母细胞减数分裂染色体制片的酶解条件为3%纤维素酶+1%果胶酶混合液在37℃下酶解3 h,结合压片和冷冻脱盖片,可获得细胞分散度良好,细胞质薄,背景干净,染色体形态清晰的制片,适用于FISH分析。2)45S rDNA探针信号定位于‘银中杨’3条同源染色体上,它们在中期I呈现III、II+I、I+I+I 3种配对形式,其中三价体发生的频率最高,达69.28%,II+I和I+I+I的配对类型分别占28.10%和2.61%,表明信号所定位的染色体亲缘关系可能较近,但也存在联会松弛的现象。3)约80.37%~93.44%的细胞在后期I至中期II发育阶段呈现2/1分离模式,约63....  相似文献   
104.
105.
Journal of Plant Diseases and Protection - A broad range of different Fusarium (F.) species is associated with Fusarium head blight (FHB) on barley and the corresponding negative effects in...  相似文献   
106.
This research was conducted to determine the changes in the seasonal carbohydrates of annual shoots and growth characteristics of 10 years old ‘Trakya ?lkeren’ grape variety. Grapevines are grafted on 5BB and 5C rootstocks and they were grown in heavy clay soil conditions. In the study, changes of sugar, starch and total carbohydrates were determined from bud burst to dormancy. While sugar, starch and total carbohydrates showed significant differences (P < 0.01) there were no differences between rootstocks. Although sugar, starch and total carbohydrates of shoots decreased from bud burst to blooming, they increased thereafter until vegetative growth stopped. Total carbohydrates of annual shoots have been found to accumulate in period from blooming to harvest. Total and mean leaf area, shoot length and diameter, total chlorophyll and chlorophyll a/b ratio showed significantly variation among rootstocks and phenological stages (P < 0.01). Whereas the highest chlorophyll contents were found in the blooming, it was found at the lowest through to harvest. Overall mean and total leaf area, shoot length and shoot diameter, total chlorophyll content and chlorophyll a/b ratio were significantly higher on 5BB grafted vines. In the study, 5BB rootstocks are found suitable in terms of shoot carbohydrate accumulation and growth characteristics for ‘Trakya ?lkeren’ grape variety.  相似文献   
107.
This study was carried out in ?scehisar district of Afyonkarahisar on ‘0900-Ziraat’ sweet cherry cultivar for two successive years in 2011 and 2012. Ten different applications consisting of 80?g FeSO4.7H2O tree?1, 20?g FeEDDHA tree?1, 420?mL TK?-Hümas tree?1, 80?g FeSO4.7H2O + 420?mL TK?-Hümas tree?1, 200?g powder sulphur (S) tree?1, 80?g FeSO4.7H2O + 200?g powder S tree?1, 25?g ZnSO4.7H2O tree?1, 25?g ZnSO4.7H2O + 420?mL TK?-Hümas tree?1 and 25?g ZnSO4.7H2O + 200?g powder S tree?1 were subjected for determination of their effect on vegetative growth of sweet cherry. In this study, shoot diameter, shoot length, leaf total chlorophyll content, leaf area and leaf iron (Fe) and zinc (Zn) contents were obtained. Shoot length, shoot diameter and leaf area showed general increases in 80?g FeSO4.7H2O + 200?g powder S tree?1 and 25?g ZnSO4.7H2O + 200?g powder S tree?1 treatments.The results clearly indicated that he treatments had different effects on the shoot length and shoot diameter although there was a differences between the experimental years. Particularly, significantly positive effects of the treatments on leaf total chlorophyll was apparent for the second year’s observations. In addition, Fe and Zn concentrations in leaf were markedly increased in response to the treatments.  相似文献   
108.

Context

Human–nature interactions are reflected in the values people assign to landscapes. These values shape our understanding and actions as landscape co-creators, and need to be taken into account to achieve an integrated management of the landscape that involves civil society.

Objectives

The aim of this research was to increase the current knowledge on the most and least common landscape values perceived by local stakeholders, the patterns in the spatial distribution of values, and their connection to different socio-economic backgrounds and landscape characteristics across Europe.

Methods

The research consisted of a cross-site comparison study on how landscape values are perceived in six areas of Europe using Public Participation GIS surveys. Answers were analysed combining contingency tables, spatial autocorrelation and bivariate correlation methods, kernel densities, land cover ratios, and viewshed analyses. Results were discussed in the light of findings derived from other European participatory mapping studies.

Results

We identified shared patterns in the perception of landscape values across Europe. Recreation, aesthetics, and social fulfilment were the most common values. Landscape values showed common spatial patterns mainly related to accessibility and the presence of water, settlements, and cultural heritage. However, respondents in each study site had their own preferences connected to the intrinsic characteristics of the local landscape and culture.

Conclusions

The results encourage land planners and researchers to approach landscape values in relation to socio-cultural and bio-physical land characteristics comprehensibly, acknowledging the complexity in the relationship between people’s perception and the landscape, to foster more effective and inclusive landscape management strategies.
  相似文献   
109.
In this paper, it was aimed to obtain disposable medical textiles having antibacterial and wound healing properties, as well as biological adaption. For this purpose, the St. John’s Wort oil and flax seed oil were ozonated, and the oils were capsulated with arabic gum. The produced ozonated oils were characterized through FTIR and TGA analyses, as well as the properties of antibacterial, wound healing, and biological adaption were investigated. The produced microcapsules were examined via optical microscope and FTIR. The characterized microcapsules of the ozonated oils were applied to the textiles with padding method. After the applications, the fabrics were researched with SEM and FTIR analyses; in addition the antibacterial and wound healing properties and biological adaption of the textiles were also investigated. The results showed that the St. John’s Wort oil and flax seed oil were successfully ozonated and microcapsulated. The microcapsules of the oils could be applied to the fabric samples with the determined application recipe. The ozonated oils and the fabric samples applied microcapsules of the ozonated oils gained high antibacterial and wound healing property. In addition, the fabric samples were produced as having biological adaptation.  相似文献   
110.
Journal of Soils and Sediments - Pesticide contamination of river waters is a global problem, and therefore, authorities regularly monitor the water quality status. Especially, flood events might...  相似文献   
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