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为提高日本落叶松种子园肥料利用率,有效改善种实性状,提高种子产量和品质;在甘肃省沙坝落叶松/云杉国家良种基地,以30年左右正常开花结实的日本落叶松嫁接无性系分株为研究对象,采用随机试验设计,设置了N1P1K1、N1P2K1、N1P1K2施肥配比水平,以不施肥(N0P0K0)作为对照,研究N、P、K不同配比水平施肥对种实性状的影响。数据采用SPSS 16.0进行方差分析和多重比较,结果表明:N、P、K不同配比水平施肥对日本落叶松结实母株种实性状的影响具有显著差异(P<0.05),不同配比施肥均能促进球果和种子性状的有效改善,N1P2K1、N1P1K1、N1P1K2配比水平施肥千粒质量分别比对照提高了38.1%、32.1%和30.0%;尤其以N1P2K1的效果最为显著,球果鲜质量和单个球果平均生产种子质量是对照(N0P0K0)的2.08倍和2.26倍,也是N1P1K2施肥配比水平的1.53倍,高出N1P1K1施肥配比水平的9.4%和30.0%。30年左右日本落叶松种子园能有效改善种实性状,提高种子产量和品质的N、P、K施肥配比水平为N1P2K1。 相似文献
3.
Du Hwan Chun 《Fibers and Polymers》2017,18(9):1790-1795
The numerical analysis was performed to predict the potential problem, often occurring during the manufacturing process of the disposable medical device of a great volume. The cavity filling analyses were performed for the new design of the 3cc Syringe Barrel using polypropylene(PP1), and a new nucleated polypropylene(PP2) material for better clarity. These analyses have been performed for different processing conditions as well as various wall thickness designs for both materials. With the nucleated material, only the original wall thickness design has been studied at two different processing conditions for comparison purpose. This study was conducted to investigate the optimum part design and processing condition for two different materials. The most desirable design was selected with Design 3 for material utilization and reduced flow stresses by comparing the field results. The new nucleated polypropylene provided slightly better product quality and processing. 相似文献
4.
针对集中供热设备标准化、系统化管理,提出了建议与探讨,能更好的满足节能减排和优化城市环境的要求。 相似文献
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Cristina E. Almeida-Naranjo Patricio J. Espinoza-Montero Marcelo I. Muñoz-Rodríguez Cristina A. Villamar-Ayala 《Water, air, and soil pollution》2017,228(7):253
Hydraulic retention time (HRT) influence improving sludge flocculation with adding the polyelectrolytes (non-ionic, anionic, and cationic) was studied on an activated sludge (AS) system fed with synthetic domestic wastewater (SDW), dairy industry wastewater (DIW), and caramel industry wastewater (CIW). The sludge volumetric index, food/microorganism ratio (F/M), and mixed liquor volatile suspended solids at different HRTs (6, 8 and 10 h) were monitored on an experimental model. Results showed that both SDW and IW had the best sludge flocculation conditions at 8 h and 100 mL of non-ionic polyelectrolyte (0.2 mg L?1). In addition, this phenomenon reached the organic matter removal efficiencies of 95.9, 95.7, and 94.2% for SDW, DIW, and CIW, respectively. Therefore, optimum HRT increased the organic matter removal efficiencies by 10%, sludge concentration by 37% (22–55%), and F/M ratio by 70%. Moreover, the polyelectrolytes used in AS improved the sludge flocculation by 2.9 times. 相似文献
7.
Stacy N. Galleher Matthew R. Gilg Kelly J. Smith 《Fish physiology and biochemistry》2010,36(3):731-740
Fundulus heteroclitus and F. grandis are resident salt marsh fishes that overlap in distribution over a narrow range in northeastern Florida. The objective of
the present study was to examine whether the limits of the species’ ranges could be explained by differences in thermal tolerance.
Two populations of each species were collected and then spawned in the laboratory, and 9-day-old larvae were used for critical
thermal maxima trials. Mean LOE temperatures of larvae ranged from 43.04 to 43.65°C and showed little difference between species.
Therefore, differences in high temperatures experienced cannot account for the differences of the distributions of the two
species. Condition-specific competition may play a greater role in determining the observed range of the two species. 相似文献
8.
During three consecutive seasons, two different deficit irrigation strategies were compared with control fully irrigated trees
regarding their capacity to induce early bloom and harvest in “Algerie” loquat. The first strategy, a continuous deficit irrigation
strategy, consisted in a uniform reduction of 20% water needs through the entire season; the second strategy, a regulated
deficit irrigation approach, while accounting for the same global reduction of 20% loquat water needs, concentrated water
shortages after harvest from mid-May through the end of August. Regulated deficit irrigation resulted more successful. Postharvest
regulated deficit irrigation advanced full bloom 10–20 days depending on the season. Such enhancement led to more precocious
and valuable yield, with an average increase of fruit value of 0.21 € kg−1. The effects of continuous deficit irrigation were less noticeable and average fruit value was increased 0.08 € kg−1. Yield and fruit quality were not affected for the different deficit irrigation strategies. Water savings established around
1450 m3 ha−1 year−1. Deficit irrigation rose water use efficiency up to more than a 40%. 相似文献
9.
在对中国潜在产出测算研究状况进行评介的基础上,分别使用H-P滤波法和生产函数法估算了中国1978—2004年间的潜在产出、产出缺口和潜在产出增长率。结果表明:(1)1978—2004年间,中国的产出缺口出现了波动水平正负交替的周期情形;(2)1995年以前产出缺口的波动幅度比较剧烈且较为频繁,1996年特别是1999年以后产出缺口的变化较为平缓;(3)1997年以后,虽然经济的增长率保持较高的水平,但是生产要素的实际利用水平却逐渐降低;(4)生产函数法得到的结果基本客观的反映了改革开放后,中国开始从计划经济向市场经济过渡到市场经济初步建立这一时期的生产要素使用情况。(5)根据H-P滤波法和生产函数法估算的潜在产出,得到1978—2004年间的平均潜在产出增长率分别为9.54%和9.67%。根据估计结果,在今后几年,通过适当的宏观调控,把中国的经济增长率稳定在8%~9%可能是一个较好的选择。 相似文献
10.
Ayu-Lana-Nafisyah Endang-Dewi-Masithah Kazumi Matsuoka Mirni-Lamid Mochammad-Amin-Alamsjah Shizuka O-hara Kazuhiko Koike 《Fisheries Science》2018,84(5):877-887
Mangrove forests and adjacent creeks are known to be highly productive estuaries, which are partly supported by benthic microalgae that grow on the sediments. During surveys investigating the microalgal floras of mangrove swamps in the eastern part of Java Island, a mud sample unexpectedly included large numbers of a notorious fish killer, Chattonella-like motile cells, and its resting cysts. These motile cells were established as clonal cultures for further identification and physiological tests. The cysts were examined through palynological and molecular biological means. Identification based on light microscopy and ribosomal RNA gene sequences confirmed that these cells and cysts were Chattonella marina var. marina. While the strains were genetically identical to the temperate strains isolated from Japan and China, temperature experiments showed that the Indonesian strains possessed a high maximum quantum yield of photosystem II even after exposure to 34 °C, a temperature at which the Japanese strain could not survive. Salinity experiments showed adaptation of the strains to a salinity of 15. These findings, together with the discovery of populations of cysts in the mangrove sediment, highlight the tough and unique nature of the Indonesian strains, which are likely adapted to wide fluctuations of temperature and salinity in mangrove swamps, and pose a potential risk to fisheries in Indonesia. 相似文献