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香港海洋公园的蝴蝶屋文/邱守思香港海洋公园以其范围广阔、规模宏大、设施多样,吸引着国内外游人。而其中设置的蝴蝶屋,则更具特色,让长期生活在城镇的人们,一饱蝴蝶飞舞的眼福。在公园东部的小山坡上,蝴蝶屋由10节透明的半圆形玻璃框架所构成,从远处望去恰似一... 相似文献
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A new method of simultaneous determining Cu(II), Zn(II), Fe(II), Mn(II), Co(II) and Ni(II) with a single sweep polarography
was developed. The experiment condition was studied and the results show that the optimum base solution is that the residue
got from evaporating 25 mL mixed solution, 2.5 mL 1.0 mol/L ethylenediamine, 3.0 mL 1.0 mol/L ammonia-ammonium chloride, 5.0
mL 10 % sodium sulfite and 0.5 mL 0.5 % gelatin were mixed and diluted to 25 mL with water. Under the condition of this base
solution, the polarography wave shapes of the six cations are ideal and without overlap of the peaks. In this base solution,
Cu(II), Zn(II), Fe(II), Mn(II), Co(II) and Ni(II) in synthetic samples were determined with relative errors 0.4–9.4% and relative
standard deviations 0.8%-12.2%. Under this experiment condition, one fold of Pb(II), Cr(VI) and Mo(VI) do not interfere with
the determination for Cu(II). This method has been used to the simultaneous determination of the amount of the six cations
in the samples of soil and Beiqi Tea. The relative standard deviations were 0. l%-2.1% and recoveries were 93.5%-99.0 %. 相似文献
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运用Cytb 和12s rRNA 基因鉴别梅花鹿(Cervus nippon)和马鹿(Cervus elaphus)的研究 总被引:2,自引:0,他引:2
本研究介绍了运用细胞色素b基因和12s核糖体RNA基因部分序列的系统学和核甘酸距离分析来鉴别降解的梅花鹿和马鹿样品。采用PCR和直接测序技术获得了8份嫌疑样品402bp细胞色素b基因序列,并与来自GenBank数据库27份同源的细胞色素b基因序列进行比对。3份嫌疑样品与梅花鹿的核甘酸距离值相同(0.026±0.006),小于梅花鹿与东部马鹿间最小的核甘酸距离值(0.036)。并且梅花鹿和马鹿的系统学分析表明这些样品与梅花鹿聚为一枝,因此可以推测它们来源于梅花鹿。同样的方法得出另3份嫌疑样品来源于马鹿。该结果被387bp12s核糖体RNA基因序列的系统学和核甘酸距离分析进一步证实。该方法是有效的,花费的时间少,能帮助减少同类野生动物案件的发生。图2表1参13。 相似文献
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There is growing concern about remote sensing of vertical vegetation density in rapidly expanding peri-urban interfaces.A widely used parameter for such density,i.e.,leaf area index (LAI),was measured in situ in Nanjing,China and then correlated with two vegetation indices (VI) derived from multiple radiometric correction levels of a SPOT5 imagery.The VIs were a normalized difference vegetation index (NDVI) and a ratio vegetation index (RVI),while the four radiometric correction levels were i) post atmospheric correction reflectance (PAC),ii) top of atmosphere reflectance (TOA),iii) satellite radiance (SR) and iv) digital number (DN).A total of 157 LAI-VI relationship models were established.The results showed that LAI is positively correlated with VI (r varies from 0.303 to 0.927,p < 0.001).The R 2 values of "pure" vegetation were generally higher than those of mixed vegetation.The average R 2 values of about 40 models based on DN data (0.688) were higher than that of the routinely used PAC (0.648).Independent variables of the optimal models for different vegetation quadrats included two vegetation indices at three radiometric correction levels,indicating the potential of vegetation indices at multiple radiometric correction levels in LAI inversion.The study demonstrates that taking heterogeneities of vegetation structures and uncertainties of radiometric corrections into account may help full mining of valuable information from remote sensing images,thus improving accuracies of LAI estimation. 相似文献
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弱光条件下光质对喜树生理生化指标的影响 总被引:1,自引:1,他引:0
为给喜树栽培提供理论依据,对弱光环境下红、黄、蓝、绿等光质对喜树幼苗叶绿素含量、超氧化物歧化酶活性、丙二醛、游离脯氨酸和喜树碱含量的影响进行了研究。结果表明:绿光使叶绿素含量增加,而其它单色光使叶绿素含量降低,减少部分主要是叶绿素b,叶绿素(a/b)比值升高;与白光相比黄光使叶片中的超氧化物歧化酶活性升高,而其它3种光条件下的超氧化物歧化酶活性降低;红光使丙二醛含量升高,同时使叶内游离脯氨酸含量持续上升,其它3种光对游离脯氨酸和丙二醛含量影响不大;与白光相比,绿光和红光可使叶片中喜树碱含量增加,而黄光和蓝光不能引起喜树碱含量的增加。弱光条件下不同光质对喜树幼苗生长形成了胁迫,光质对其初生和次生代谢均产生了一定的影响。 相似文献
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本文主要利用艾虎(Mustila eversmanni)气味作为捕食风险源,于1997年4月至12月在中国科学院西北高原生物研究所生态学实验室,研究其对根田鼠(Microtus oeconomus)社会行为、觅食、繁殖和性激素的影响。结果表明,当暴露于艾虎气味中时,根田鼠产生繁殖迟滞,且交配行为的频率显著降低(P<0.01)。与对照组相比较,雌体亲密行为和两性一般动作的累积时间显著增加(P<0.01)。两性一般动作(P<0.01)、探究活动(雌体:P<0.05;雄体:P <0.01)和自我修饰(P <0.01)的频次显著降低。同时,根田鼠能量的摄入(P<0.05)和体重(P<0.01)都显著降低。雌体的卵巢指数和胎仔重量也显著降低(P<0.01),雄体的附睾精子数则极显著降低(P<0.01)。艾虎气味条件下,根田鼠雌体的血清孕酮显著增加(P<0.01)。 相似文献
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松材线虫侵染对马尾松苯丙烷类代谢的影响 总被引:9,自引:1,他引:9
1.5年生马尾松植株接种松材线虫后,苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)、多酚氧化酶(PPO)的活性水平均高于对照,活性高峰通常出现在症状表现前夕,并在植株发病后下降.叶内PAL和POD活性高峰的出现晚于茎,与叶部病害发展一致.茎中酚类物质的含量随着线虫侵染时间的延长逐渐增加,至发病时达到高峰.酚类物质含量的变化与PAL、POD、PPO 3种酶活性的变化趋势基本一致.松材线虫的侵染明显影响寄主植物的苯丙烷类代谢,由此可知,松材线虫病的发生发展与松材线虫诱导感病寄主苯丙烷类代谢的异常变化有关. 相似文献
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An attempt was made to examine the possible connection between the various ratios of calcium/aluminum (Ca/Al) in the nutrient
solution of plant cultures and the active oxygen scavenging system of hinoki cypress (Chamaecyparis obtusa) seedlings. The hinoki cypress seedlings were transferred to nutrient solutions containing 5 mM AlCl3 together with various concentrations of Ca(NO3)2 in pots containing glass beads and Teflon tips. The activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase
(APX) and glutathione reductase (GR) in the needles were estimated at several stages during the 7-day treatment. The samples
treated with the lower Ca/Al solutions show the highest SOD activities. The activities of APX and GR, both of them involved
in the ascorbate-glutathione cycle, showed the same tendency with decrease to higher Ca/Al ratio. These results indicate that
rhizospheric Ca might compete with Al and ameliorate Al toxicity on and in the roots, the Al stress is not transformed to
the needles after a few days, and the ascorbate-glutathione cycle in the hinoki cypress needles might fluctuate and be suppressed
by the rhizospheric Al stress during the 7 days.
This work was supported in part by funding from the Japan Science & Technology Corporation, the CREST program 1996–2001, and
the Center for Forest Decline Studies. 相似文献
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ACQ和CuAz防腐处理对木材力学性能的影响 总被引:9,自引:2,他引:9
采用水溶性铜防腐剂(ACQ)和铜唑类防腐剂(CuAz)加压浸注处理臭冷杉木材,研究了药液处理浓度和后期干燥条件对木材抗弯弹性模量和抗弯强度的影响。t检验表明,本试验条件下,经两种防腐剂处理后,木材的抗弯弹性模量保持不变或略微增加。通过分析与对照素材试件的t检验比较,表明两种防腐剂处理前、后木材的抗弯弹性模量差异不显著。ACQ和CuAz防腐处理对木材抗弯强度有一定影响,ACQ处理使得木材抗弯强度整体上略有下降,而CuAz处理由于保持量相对较低,对木材抗弯强度未见明显下降趋势。后期干燥方式对木材抗弯强度亦未见明显规律性的影响。 相似文献
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BearisveryvaIuableeconomicanimal.BearresourcereducedsharplywithMan'sexploitingandutilizingonnatufe,wbrseningofecologicalenvirorunent.Itisveryvaluabletoaccumulatebasicbiologicaldataofbcarre-searchinordertostudybcarpopulationecol-ogyindetail,providescientificbasisforbearresourcemanagement,thcnccdofarchacologr'andthestUdy'onthedataofnatUraldeathinfield.Toothisthemostdifficultdecomposedpall,sotheywillprovidcalotofinformationduringtheproccssofstudyonarchaeologyandnatllfaldeathindividual.Itisavery… 相似文献