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961.
962.
闽南沿海沙质地区希蒙得木的引种 总被引:1,自引:0,他引:1
陈胜 《东北林业大学学报》2007,35(3):15-17,20
引种试验表明:希蒙得木在闽南沿海温暖潮湿的沙质地区不论原种或子代都生长良好、能自然开花结果,物候期及生长规律表达稳定,种子含油量及品质与原产地基本一致,引种试验成功;但由于病虫害等原因,希蒙得木在引种点无人为管理的情况下无法自然生存。沙地良好的通透性和林地良好的排水性是希蒙得木能承受当地高达1325mm年降雨量的主要原因,也是希蒙得木在闽南沿海沙质地区引种成功的主导因子;希蒙得木在引种点的耐旱性不强,旱季浇水有助于植株生长。 相似文献
963.
通过原位聚合制备了纳米氧化锌颗粒增强不同添加量和分子量的聚乙二醇(PEG)与聚对苯二甲酸乙二醇酯(PET)共聚物的复合材料。研究了纳米粒子在基体里的分散,以及纳米粒子和PEG对复合材料结晶行为的影响。结果显示,纳米粒子在基体中以纳米尺度分散起晶核作用。PEG的加入使得纳米粒子分散更加均匀,PEG分子链段改善了PET分子链的柔性,由此导致复合材料的冷结晶温度降低,结晶速率提高。研究发现,当添加10%分子量为4000的PEG时,复合材料的结晶速率快速提高。复合材料的力学性能结果说明,纳米粒子对PET基体有增强增韧作用,但PEG会弱化该作用。 相似文献
964.
Seedling crops of gazania, geranium, marigold, mimulus, pansy, verbena and vinca were grown to 60% anthesis in three greenhouse temperature regimes: (a) 26 °C day/6 ± 3 °C night (LT), with a 16.5 °C mean daily temperature (MDT), (b) 26 °C day/17 ± 4 °C night, with a 21 °C MDT, and (c) variable day/night temperatures in response to heating and cooling by a phase change material energy storage module (PCM) with an 8 ± 2 °C night and a 16 °C MDT. Crops bloomed from 2 to 17 days earlier in the 26 °C/17 °C greenhouse. The morphological characteristics of all cultivars of gazania, mimulus, pansy and verbena, geranium and vinca were similar regardless of greenhouse temperature regime. Marigold diploid and triploid cultivars and mimulus were morphologically more variable than the other bedding plant species. Crops grown in the PCM and LT greenhouses had virtually identical morphological characteristics and bloomed in about the same number of days. Plant height was not affected by DIF environments in the greenhouses. The PCM and LT greenhouses had a similar MDT, but the distribution of numbers of hours of mean daily temperatures was different. 相似文献
965.
WANG Chao-jiang GAO Chun-yan ZHI Jian-fei Institute of Genetics Physiology Institute of Resource Environment of Agriculture Agriculture Forest Science Academy of Hebei Province Shijiazhuang Hebei China 《食用菌学报》2006,(4)
Depressed fruit sales in recent years have leftunused many pear refrigeration warehouses(PRWs)located in traditional pear-producingareas of Hebei Province such as Zhao County,Ningjin and Jingzhou.As a consequence,severalproducers have commenced cultivatingFlammulina velutipesin PRWs in order to providethis mushroom during the off-season.However,the environment insidethe PRWs resultedinloweryields and poor quality mushrooms.Amongvarious environmental factors such as temperature,illuminati… 相似文献
966.
Transformation of Upland Cotton (Gossypium hirsutum L.) with gfp Gene as a Visual Marker 总被引:1,自引:0,他引:1
The green-fluorescent protein (gfp) gene was evaluated as a screening marker during cotton (Gossypium hirsutum L.) transforming and plant regeneration.High expression of GFP (green-fluorescent protein)... 相似文献
967.
J. Vilensky N. V. Koudinova A. Harmelin A. Scherz Y. Salomon 《Veterinary and comparative oncology》2005,3(4):182-193
Treatment of canine‐transmissible venereal tumour (CTVT) with local vascular‐targeted photodynamic therapy (VTP) using Pd‐bacteriopheophorbide (WST09) as a drug is suggested as an alternative to conventional chemotherapy. Male CD1 nude mice were subcutaneously grafted with the xenograft‐transmissible canine venereal tumour (XTVT). The VTP protocol delivered once consisted of intravenous administration of WST09 (10 mg kg?1) followed by immediate local illumination with a diode laser (763 nm). Controls included animals treated with light or WST09 alone. Macroscopic and microscopic evaluations of tumour response were conducted 10, 24 and 48 h after treatment. Upon VTP, tumours underwent necrosis that lasted 8–10 days and exhibited complete healing by 25–35 days, reaching an overall long‐term cure rate (83%) by 90 days after treatment. This study suggests that VTP with WST09 can efficiently treat CTVT in a single session, as compared with 4–6 sessions of chemotherapy and thus may be feasible for common veterinary practice, particularly under ambulatory conditions. 相似文献
968.
Two experiments (I and II) were conducted to evaluate the effect of nonprotein phenolic amino acid, L ‐dopa (L ‐3,4‐dihydroxyphenylalanine) on growth, metabolism and feed assimilation of common carp. Six isonitrogenous and isoenergetic diets (diets 1–6 containing 0, 2.5, 7.0, 14, 28 and 56 g kg–1L ‐dopa, respectively) were prepared by replacing wheat meal in the feed with L ‐dopa. For experiment I (8‐week duration), each treatment had two replicates with five fish each per replicate (mean initial body mass of 13.4 ± 1.0 g), whereas five groups of carp, each consisting of three fish, individually kept in respiration chambers, giving three replicates per treatment with a mean body mass of 25.0 ± 1.8 g were used for experiment II (4‐week duration). Fish were fed six times their maintenance ration daily (3.2 g feed kg–0.8 day–1). No fish died during either experiment. In experiment I, the growth rate, feed conversion ratio (FCR), protein efficiency ratio (PER) and apparent net protein utilization (ANPU) of carp fed diets 1, 2 and 3 were similar but they were significantly (P < 0.05) higher than those in dietary groups 4, 5 and 6. However, no significant differences were observed with regard to body composition (moisture, protein, lipid, ash and energy contents) between control (1) and the diets 2, 3, 4 and 5. Fish fed diet 6 had reduced lipid and energy contents (P < 0.05) when compared with other dietary groups. In experiment II, L ‐dopa significantly increased the oxygen consumption per unit body weight gain in treatments 4, 5 and 6. The average metabolic rate also tended to be higher in these groups. The energy expenditure was similar in treatment groups, but the energy retention was significantly lower and energy dissipated significantly higher in dietary groups 4, 5 and 6. The cholesterol level in blood plasma between the control and L ‐dopa containing diets was not significantly different. It may be concluded that at higher inclusion rates (>7 g kg–1) L ‐dopa appears to be a major antinutrient and hence the protein sources of plant origin, containing high amounts of L ‐dopa (i.e. mucuna beans) should be used with caution as fish meal substitutes in carp diets. 相似文献
969.
将CM(HEM)应用于养鸡生产中,试验证明可以使肉鸡的死亡率下降1.22个百分点,日平均增重增加2.94g;使蛋鸡死亡率下降0.67个百分点,产蛋率提高2.19个百分点,蛋壳色泽及感官质量明显好转,破蛋率下降2.17个百分点;能部分代替抗生素、消毒药、抗球虫药,平均每只鸡降低用药成本0.19元;夏季还能明显减少鸡粪中蝇蛆数量,减轻圈舍中刺激性气味。 相似文献
970.
桑枝枯菌核病病原菌的生物学特性研究 总被引:7,自引:1,他引:6
从发病桑树上分离到桑枝枯菌核病病原菌的纯菌种 ,并对该菌的培养性状和生物学特性进行了调查和研究。结果表明 :桑枝枯菌核病病原菌适于在PDA培养基和桑叶汁培养基上生长 ,其生长温度范围为 8~ 30℃ ,最适生长温度为 2 0~ 2 5℃ ,生长pH值范围为 1~ 12 ,最适生长pH值为 5~ 8,菌丝与菌核的生长情况大致相同 ;菌核在适宜的温湿度条件下能够产生子囊盘和子囊孢子 ,子囊孢子椭圆形 ,大小 7~ 14 μm× 3~ 7μm。 相似文献