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41.
Golf courses have been shown to have a positive impact on local biodiversity, quality of life and the economy. However, the impacts of golf courses on local environment, including ecosystem services and dis-services are not clearly understood. To explore this relationship, we took two golf courses in Beijing (a links course and a parkland course) to develop an assessment framework and present estimates of economic values of net ecosystem services, in aspects of ecosystem goods, carbon fixation, soil retention, flood storage, recreation, water consumption and nonpoint-source pollution. The results showed that the two golf courses have provided remarkable net ecosystem services values (links 51.58 × 104 yuan/ha/yr, parkland 42.60 × 104 yuan/ha/yr, 6.19 yuan = 1 US$ in 2013). Over 95% of this value is generated by three services: recreation, ecosystem goods and flood storage. Our results indicate that the parkland course has better performance in sustainable supply of ecosystem services than the links course. In addition, this study provides useful improvements for golf course design and management concerning positive environmental externalities optimizing, including the scaling of non-playing areas to maximize golf course ecosystem services supply capacity, appropriate grass species selecting and irrigation with recycled water. Moreover, a policy analysis suggests that the development of public golf course in China is a necessary complement to resolve the mismatch between private and public benefits and let more people enjoy the ecosystem services.  相似文献   
42.
现代微生物学是面向基础医学专业硕士研究生开设的一门专业基础课程,旨在培养学生的基本科研素养和科研创造力,而传统的讲授型授课方式已无法满足新时代医学研究生教育要求。因此,本文通过专题教学与seminar教学模式(“讨论课”教学模式)相结合,设置六大专题板块辅以学生seminar汇报讨论,应用于现代微生物学研究生课程教学,探讨该教学实践的应用效果,全面提升医学研究生的知识理论水平,培养具有创新思维和具备基本科研素质的高层次医学人才,也为医学类专业其他研究生课程的教学改革提供有益参考。  相似文献   
43.
Most golf course green have been constructed with pure sand or sand-based rootzone mixes. As we know, high sand content provides rapid drainage despite sand’s inefficiency in retaining moisture. However, drainage capability and water retention are both essential elements to the golf course green, and the addition of peat could increase the soil moisture retention, therefore, the research on the drainage capability and water retention of the sandy golf green has become more and more important these years. In this study, extreme vertex design was applied which is one of the mixture experiment designs widely used in mixture experiments, the study investigated the effects of the thirteen different rootzone soil mixtures using middle-coarse, fine sand, very fine sand plus silt and clay as well as peat as the materials under three kinds of golf green profile (1-layer profile, 2-layer profile, 3-layer profile) conditions on the water retention of green rootzone. Through the qualitative, quantitative and optimization analysis of water retention capability of the sandy golf green, evidence a basis for choice of green profiles and rootzone matrix could be provided. And the significantly correlative regression model was established between the moisture retention and components of rootzone soil mixture. In addition, the order of factor contribution ratio, effect of single and double factor and optimization of the model were analyzed in detail. The results were as follows: both green profile and soil mixture, which had interaction of each other, had significant effects on soil moisture retention. Additional attributes include high porosity and greater water holding capacity than sand, and the higher content of peat, fine sand plus silt and clay, the better water retention. The mixtures had much higher water content in 1-layer profile than that in the other two profiles. There was significantly higher water content in 2-layer profile for pure sand mixtures (A–E) and low peat mixture (F) than that in 3-layer profile, while there was no higher water content for other 7 high peat mixtures (G–M) (>5%) in 2-layer than that in 3-layer profiles. The significance of key factors in rootzone soil mixture on moisture retention were: very fine sand plus silt and clay > peat > middle-coarse > fine sand. According to the moisture retention 15–25% specification of USGA (United States Golf Association), the optimal soil mixture in 1-layer profile was: middle-coarse 71.4–73.5%; fine sand 17.8–21.5%; very fine sand plus silt and clay 6.8–8.4%; peat 0–1%. The optimal soil mixture in 2-layer profile was: middle-coarse 65.0–73.4%; fine sand 17.8–20.5%; very fine sand plus silt and clay 7.5–8.9%; peat 0.2–6.3%. The optimal soil mixture in 3-layer profile was: middle-coarse 62.3– 73.9%; fine sand 17.7–21.4%; very fine sand plus silt and clay 7.3–10.7%; peat 0–6.3%. These optimal recipes took through the limitation of previous research, which were practically important to golf green soil selection and profile design. Thus, both proportion and interaction should be considered when we choose the soil mixture.  相似文献   
44.
高尔夫球场不同功能区草地优势种蛴螬种群生态位分析   总被引:4,自引:0,他引:4  
研究了亚热带高尔夫球场不同功能区优势种蛴螬种群空间分布及时间和空间的生态位.结果表明,球场4种优势种草地蛴螬时间生态位宽度几乎均在0.9以上(除果岭Ⅲ区及Ⅳ区个别蛴螬种外),其中短草高地和果岭Ⅰ、Ⅱ区中4种蛴螬时间生态位宽度均最大,长草高地和果岭Ⅳ区的时间生态位宽度则最低.除浅棕鳃金龟垂直空间生态位宽度在球道4区均达0.8以上外,其它种蛴螬在球场各区普遍偏低(0.2~0.7).在球道和果岭4区中,4种蛴螬种对时间生态位相似性指数均高达0.8以上,垂直空间生态位相似性指数大多数蛴螬种对在0.1~0.6之间,球道以铜绿丽金龟与大绿金龟种对为最高(0.8以上),果岭则是铜绿丽金龟与大绿金龟、华南大黑鳃金龟与浅棕鳃金龟种对为最高(0.8以上).垂直空间分布上,球道和果岭各区中4种蛴螬主要活动于食源最为丰富的上、中层土壤空间(0~5和5~10cm),少数出现于球道部分区10~15cm土层中活动和取食,4种蛴螬几乎不在果岭10~15cm土层中活动和取食。  相似文献   
45.
生物类专业课程思政教学改革初探——以生物化学为例   总被引:3,自引:2,他引:1  
吴伟  李慧涵 《微生物学通报》2020,47(4):1191-1195
课程思政教学改革近两年来获得广泛关注。如何在专业课教学中融入思政元素以达到二者协同育人的目的,是值得我们思考的问题。生物化学与微生物学、细胞生物学等课程具有显著的共性和关联,是生物类专业的重要基础课程。结合本科生生物化学课堂教学中的具体例子,本文介绍了课程思政教学改革的经验,重点探讨如何发掘专业知识点的思政内涵,为相关生物类专业课程思政教学改革提供参考。  相似文献   
46.
A well-orchestrated hierarchy of molecular events is required for successful initiation and maturation of clathrin-coated pits (CCPs). Nevertheless, CCPs display a broad range of lifetimes. This dynamic heterogeneity could either reflect differences in the temporal hierarchy of molecular events, or similar CCP maturation processes with variable kinetics. To address this question, we have used multi-channel image acquisition and automated analysis of CCP dynamics in combination with a new method to quantify the time courses of recruitment of endocytic factors to CCPs of different lifetimes. Using this approach we have extracted the kinetics of recruitment and disassembly of fluorescently labeled clathrin and/or AP-2 throughout the entire lifetime of temporally defined CCP cohorts. On the basis of these analyses, we can (i) directly correlate recruitment profiles of these two proteins; (ii) define five distinct CCP maturation phases, i.e. initiation, growth, maturation, separation and departure; (iii) distinguish events with absolute versus fractional timing and (iv) provide information on the spatial distribution of fluorophores during CCP maturation. Emerging from these analyses is a more clearly defined role for AP-2 in determining the temporal hierarchy for clathrin recruitment and CCP maturation. This method provides a new means to identify other such hierarchies during CCP maturation.  相似文献   
47.
Liquid culture-produced entomopathogenic nematodes, Heterorhabditis megidis and Heterorhabditis bacteriophora, were applied at 0.5 and 1.5 million dauer juveniles m-2 against Aphodius contaminatus and Phyllopertha horticola on a golf course. The reduction of A. contaminatus was found to be between 40 and 62%. P. horticola reduction reached 70% with H. megidis and 83% with H. bacteriophora. Turf damage caused by birds preying on the grubs was successfully prevented.  相似文献   
48.
Jiang  G.M.  Zhu  G.J. 《Photosynthetica》2001,39(2):257-262
Field studies of gas exchange and chlorophyll fluorescence of three desert shrub species, Hedysarum fruticosum var. mongolicum, Artemisia ordosia, and Salix pasmmophylla, showed different patterns under different leaf temperature (T1) and incident photosynthetic photon flux density (PPFD). H. fruticosum var. mongolicum and A. ordosia exhibited higher P N and g s than S. pasmmophylla, especially under very high T1 (>46 °C) and high PPFD (>2 100 µmol m–2 s–1) in hot summer. The decreases of P N with the diurnal course were due mainly to stomata closure. However, P N of S. pasmmophylla was seriously depressed by very high temperature from midday to evening as shown by the negative P N in hot summer, whereas none of such depression was found in spring. Maximal spring photochemical efficiency of photosystem 2 (PS2), i.e, Fv/Fm, was the lowest at 16:00, indicating the injury of PS2 by heat at this stage. In hot summer again, all the three shrubs underwent pronounced midday depression of P N and g s, while in spring they showed a one-peak response. And the first peak appeared 2 h earlier in hot summer than in spring for all the three shrubs. It was the high temperature that led to the different patterns of gas exchange and the serious depression of P N in S. pasmmophylla. H. fruticosum var. mongolicum and A. ordosia were much more tolerant to heat and high irradiance than S. pasmmophylla, which fixed most of CO2 at the fast growing stage in spring. Nevertheless, in hot summer it had to survive the severe hot environment through strong respiration and storage of CO2 only in the early morning.  相似文献   
49.
In vivo bioluminescence imaging (BLI) has the advantages of high sensitivity and low background. By counting the number of photons emitted from a specimen, BLI can quantify biological events such as tumour growth, gene expression and drug response. The intensities and kinetics of the BL signal are affected by many factors and may confound the quantitative results acquired from consecutive imaging sessions or different specimens. We used three different mouse models of tumours to examine whether anaesthetics, positioning and tumour growth may affect the consistency of the BL signal. The results showed that BLI signal could be affected by different anaesthetics and repetitive positioning. Using the same anaesthetics produced consistent peak times, while other factors were held constant. However, as the tumours grew the peak times shifted and the time course of BL signals had different shapes, depending on the positioning of the mice. The data indicate that a carefully designed BLI experiment is required to generate optimal and consistent results. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
50.
子午岭辽东栎群落乔木种间联结与取样面积   总被引:7,自引:1,他引:6  
以x2检验、种间联结系数(AC)、Person相关系数(r)、方差比率(馏)和某一取样面积尺度下的样方中未共同出现的物种对数目Na为参数,探讨黄土高原子午岭辽东栎群落主要乔木种间联结特性与取样面积的关系.x2检验和AC分析表明,显著的种问联结关系仅出现在25和50 m22个取样面积中;相关分析表明,显著的种间相关出现在取样面积25~200 m2,但r值的变化在25~100 m2较稳定;VR分析未能有效地区分不同取样面积中多物种关联的特性;Na值在面积为100~200 m2、样方数为40~80时较稳定.从合理的样方面积和适当的样方数量综合考虑,样方面积在100 m2、样方数为45个,能比较客观、稳定地反映辽东栎群落植物种间联结特性.  相似文献   
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