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141.
几种保鲜液对菊花切花保鲜效果的比较研究 总被引:4,自引:0,他引:4
运用4种不同保鲜液对菊花切花进行处理,研究其保鲜效果。结果表明,选择适合的保鲜液,不但能延长菊花切花的瓶插寿命,而且能促使切花增大花径,提高切花的观赏价值。 相似文献
142.
2004年华东与华南家具出口总额达到90.58亿美元,占全国家具出口总值的87.5%。其中广东出口额45.36亿美元,华东四省一市(闽、浙、苏、鲁、沪)出口额45.22亿美元。 相似文献
143.
家具是劳动密集型产业,世界各国都在走家具专业化、国际化的道路。这种家具产业集聚在国际上已成为一种共同的趋势,意大利、美国、东盟的马来西亚、印尼、菲律宾等国家都有这种家具产业群体。意大利“椅子工业三角区”是国际上产业集聚的成功典范,马来西亚建立了众多的“家具村”等等。 相似文献
144.
Decomposition dynamics were compared among green tree leaves, partially decomposed tree leaf litter (i.e., decayed tree leaf litter on forest floor) and a mixture of the two in a warm temperate forest ecosystem in central China to test the influence of litter chemical quality on the degree of decomposition. The study was conducted in situ at two contrasting forest sites, an oak forest dominated by Quercus aliena var. acuteserrata Maxim., and a mixed pine and oak forest dominated by Pinus armandii Franch. and Q. aliena var. acuteserrata. We found marked differences in the rate of decomposition among litter types at both forest sites; the litter decomposition constant, k, was about 39 % greater at the oak forest site and more than 70 % greater at the pine-oak forest site, for green leaves than for partially decomposed leaf litter. The decomposition dynamics and temporal changes in litter chemistry of the three litter types also greatly differed between the two forest sites. At both forest sites, the higher rate of decomposition for the green leaves was associated with a higher nitrogen (N) content and lower carbon to N ratio (C/N) and acid-unhydrolyzable residue to N ratio (AUR/N). We did not find any non-additive effects when mixing green leaves and partially decomposed leaf litter. Our findings support the contention that litter chemical quality is one of the most important determinants of litter decomposition in forest ecosystems at the local or regional scale, but the effect of litter chemical quality on decomposition differs between the contrasting forest types and may vary with the stage of decomposition. 相似文献
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146.
龙南遗址红烧土植物蛋白石分析郑云飞,游修龄,徐建民,边其均(浙江农业大学,杭州310029)PlantOpalAnalysisofLongnanNeolithicSite¥ZHANGYunfei;YouYiuling;XuJianmin;BIANQi... 相似文献
147.
Li Yanan Zhang Tengzi Zhou Yongbin Zou Xiaoming Yin You Li Hui Liu Liying Zhang Songzhu 《European Journal of Forest Research》2021,140(5):1039-1048
European Journal of Forest Research - Ectomycorrhizal fungi (EMF) can enhance drought resistance of host plants by increasing nutrient and water absorption. Calcium (Ca) plays a central role in... 相似文献
148.
149.
Youwen You Cornelius E. Uboh Lawrence R. Soma Fuyu Guan Daniel Taylor Xiaoqing Li Ying Liu Deborah Tsang 《Journal of Equine Veterinary Science》2014
A liquid chromatography–tandem mass spectrometry method was developed to confirm the presence of androstenedione-19-oic acid in intact male equine plasma and to show the source of 19-norandrostenedione in equine plasma. Androstenedione-19-oic acid was recovered from acidified plasma by liquid–liquid extraction using methyl tert-butyl ether and separated on an Ace 5 C8 column. A triple quadrupole mass spectrometer was used to detect the analytes in negative electrospray ionization mode. Limits of detection, quantification, and confirmation of the method were 0.1, 0.5, and 1.0 ng/mL, respectively. The linear dynamic range of quantification was 0.5–50 ng/mL. The presence of androstenedione-19-oic acid was confirmed in all plasma samples obtained from intact male horses but not those from gelded and female horses; the average concentration was 3.1 ± 1.6 ng/mL, suggesting androstenedione-19-oic acid is an endogenous compound only in intact male horse plasma samples. The conversion of androstenedione-19-oic acid to 19-norandrostenedione in equine plasma was demonstrated by spiking androstenedione-19-oic acid into blank plasma and monitoring the generation of 19-norandrostenedione and its increase in concentration during storage. Results indicated that androstenedione-19-oic acid was readily converted into 19-norandrostenedione; the higher the storage temperature, the faster the conversion. The conversion was not affected by the types of plasma samples collected from gelded and female horses or by anticoagulants used in blood collection to harvest plasma. Compared with other matrices such as water, methanol, and phosphate-buffered saline, the conversion of androstenedione-19-oic to 19-norandrostenedione in equine plasma was faster, suggesting that there is an unknown factor(s) in equine plasma that enhances the conversion. 相似文献
150.