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71.
Analyses of stable isotopes(C, O, H) in tree rings are increasingly important cross-disciplinary programs. The rapid development in this field documented in an increasing number of publications requires a comprehensive review. This study includes a bibliometric analysis-based review to better understand research trends in tree ring stable isotope research. Overall, 1475 publications were selected from the Web of Science Core Collection for 1974–2023.The findings are that:(1) numbers of annual pu... 相似文献
72.
73.
为了测算园林树木的蒸腾耗水量,应用热脉冲技术对阿克苏市3种常见绿化乔木(小叶白蜡、法国梧桐、桑树)进行树干液流的测定,并分析其日变化规律,同时运用自动气象站记录各气象参数数据,分析树干液流日变化与气象因子之间的相关性。结果显示：3种乔木树干液流速率之间有一定的差异,但其日变化过程几乎相似,均有明显的昼夜变化规律。白天的液流速率比夜间大,午间由于太阳辐射( Rs)过强出现午休现象,凌晨和晚上树干液流速率较低,夜间保持微弱的树干液流过程。小叶白蜡、法国梧桐、桑树等树干液流日变化都与太阳辐射、空气温度( Ta)、风速( Ws)呈显著正相关,而与空气湿度( H)呈显著负相关;逐步回归模型显示,影响小叶白蜡树干液流的主要气象因子是太阳辐射和空气湿度,模型拟合度为0.962,法国梧桐的是空气温度和空气湿度,拟合度为0.971,桑树的是空气温度和太阳辐射,拟合度为0.915。不同乔木的日累计液流量大小排序为小叶白蜡(57000±2400) mL﹥法国梧桐(55400±2100) mL﹥桑树(7600±1800)mL。 相似文献
74.
为比较3种禽白血病病毒(ALV)抗原检测ELISA试剂盒的特异性和灵敏度,将J亚群禽白血病病毒(ALV-J)传染性克隆rNX0101株以病毒原液(9×103TCID50)、10倍病毒稀释液(9×102TCID50)、100倍病毒稀释液(90 TCID50)接种培养于6孔板的DF1细胞,每孔均提前放入灭菌的细胞爬片,于接种后第1~6天每天取上清用3种ELISA试剂盒(A、B、C)检测ALV p27抗原,同时在接种后的第3天和第6天取出细胞爬片进行间接免疫荧光法(IFA)检测。结果表明,IFA方法对高、中、低剂量接种3 d后均可检出ALV-J的感染,而ELISA试剂盒中只有A试剂盒在高剂量接种时才能检出,试剂盒B和试剂盒C最早要在第4天才可检出;中、低剂量接种,3种试剂盒在第4~5天才能检出;第6天时,由于病毒的明显复制,无论IFA方法还是3种ELISA试剂盒都可检出ALV-J的感染。本研究结果为正确选择商品化禽白血病抗原检测试剂盒提供了借鉴。 相似文献
75.
Scots pine( Pinus sylvestris L.) is a dominant tree species on nutrient-poor sandy soils in the Baltic region’s hemiboreal forests. A final clear-cut in commercial stands is a common practice. However, the maintenance of relatively stable vegetation indices and ecological processes throughout the rotation promote new scientific and social debates. Overall, clear-cuttings disturb forest functions for a certain period, i.e., phytocenoses with forest-based species composition, biodiversity, and veg... 相似文献
76.
含笑(Michelia figo(Lour.)Spreng.)Banana Shrud Phyllosticta magnoliae Sacc.(叶斑病) 症状:为害叶片,病斑长椭圆形至不规则形。灰色,灰褐色至茶褐色,边缘暗褐色,窄,略隆起,有时伴随表皮纵裂。后期在病斑上散生许多小黑点,即病原的分生孢子器。病原:分生孢子器埋生在寄主表皮下,微露,球形,具孔口,深褐色,直径150—180微米;器孢子丰富,椭球形,圆柱形,卵形至不规则形,直或稍弯曲,无色,单胞,个别长的 相似文献
77.
草莓(Fragaria ananassa Duchesne)Garden Strawberr yBotrytis cinerea Pers.(灰腐病)。症状:只见为害浆果及病果果柄。接触地面的,尤其是潮湿土壤地面的浆果罹病颇多。紧贴地表处的果尖常最先受害。当浆果接近成熟时,首先见受病处失色,苍白软腐,组织着浓疱状膨大。病区迅速向上部蔓延,可使全果软化腐烂,并延及果柄,使果柄也变褐腐烂。病果具酒精异味。约1—2天后,病果自初受染处开始失水干燥,萎缩并变褐色,终至使全果(包括果柄在内)变成褐色干瘦的木乃伊状,果面生较稀疏或密集地白色霉状物,后期霉状物变鼠灰色,是病原菌的子实体。 相似文献
78.
Experimental study of condensation heat transfer of HC600a-oil mixture in a horizontal micro fin tube is performed to investigate the inflence of oil percentage, saturated pressure and mass flux on condensation heat transfer.The empirical correlation according to this study is well correlated by the experimental data. By comparing with other refrigerants, HC600a has no inflence on ozone depletion and better heat transfer characteristcs than CFC12 and HCFC134a. It is a promising substitute for CFC12. 相似文献
79.
ECG is an important method in clinical heart disease diagnosis. The storing of lots of ECG and other corresponding materials in information management system has great value to medical researcher for their reference and research. Embedding the ECG information management system to virtual ECG instrument is not only enhanced the operating value but also increased the functions to virtual ECG instrument. The model of relation database and ActiveX Data Object (ADO) of VC++6.0 is used in the system. The key functions of Storing,Query,Deleting and core modules are introduced. 相似文献
80.
Bake out of Aluminum reduction cells will affect the normal production and the ultimate life of reduction cell directly. The method of thermal bake out is a key of novel technology which possesses such advantages as well distributed temperature, easy control for the speed of heating up, fully baking for the joint and ramming paste of the edge. The design of the burner is a key technology of thermal bake out. A new high speed rectangle burner has been developed based on the experiment, and the structure of this burner has also been optimized. The new burner an fire easily, burn stably and fully, and has high ratio of load adjustment, and low noise, etc.. It can meet the needs of thermal bake out reduction cells. Its development can provide the technological guarantee for the use of thermal bake out Aluminum reduction cells. 相似文献