285 resultados para 2-9
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本文分析了翁牛特旗46年(1957-2002年)逐月降水量和平均气温。结果表明:气温呈非连续增暖趋势,其中年平均气温线性变化率为0.39℃.(10a)-1,年平均最高气温线性变化率为0.19℃.(10a)-1,年平均最低气温线性变化率为0.93℃.(10a)-1;最低气温上升速率是最高气温的1-4倍,气温日较差显著减小。上世纪60年代较50年代有所增暖,80年代后期开始明显升温,90年代是近50年来最暖的10年。1987年开始转暖,其后呈连续性增暖趋势,1998年为1957年以来的最暖年,年平均气温7.7℃,高于1957年2.9℃。降水以平均5-7年的周期变化,并从50年代到90年代呈连续性递减趋势,线性变化率为-11.7mm.(10a)-1,90年代较50年代年降水减少了39.4mm。
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目的 :探索培养的人大肠癌细胞内质网膜系统超微结构与其分化程度间的关系。方法 :采用透射电镜技术和扫描电镜技术分别观察了培养的高分化和低分化大肠癌细胞系 CCL 2 2 9和 CCL 2 2 7内质网膜微细结构和分布。结果 :透射电镜观察结果显示 :高分化细胞 CCL 2 2 9内质网较丰富 ,呈小泡状和扁平囊状分布于核周及质膜下胞质中 ,其伪足中亦见丰富的内质网。低分化的 CCL 2 2 7细胞中内质网较少 ,呈小泡状、短管状分布于胞质中。扫描电镜观察两个细胞系内质网立体结构显示 :内质网在数量和分布上与透射电镜观察结果相似。结论 :培养的人大肠癌细胞内质网的数量和分布与细胞的分化程度有关 ,高分化细胞的内质网较丰富且分布于整个细胞中
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本研究旨在探讨应用复合酶提高肉鸡生产性能与适当降低代谢能及蛋白,使加酶后的饲料配方更趋合理。试验中对照组喂常规肉鸡浓缩料,试验1组喂加酶常规肉鸡浓缩料,试验2组喂加酶减豆粕浓缩料,三组中的玉米添加比例相同,调饲料配方后的1t浓缩料可降低成本126元。试验结果表明,试验1组与试验2组分别比对照组提高肉鸡增重9.4%与6.3%,经济效益提高24.3%与14.1%。
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对农田污灌区污水和土壤监测结果表明 ,土壤中Cd、As、Hg、Cu、Pb、Cr和Zn等含量为当地环境背景值的1 5 5~ 5 2 9倍 ,其中Cd和As含量分别为国家土壤环境质量 2级标准的 3倍和 1 4 2倍。污水中 7种重金属含量为农田灌溉水质标准的 4 8~ 34倍 ,部分有机污染物含量为灌溉水质标准的 1 1 0~ 1 87倍。以 3级标准为最大容量限值 ,土壤重金属达土壤环境容量的污灌年限估算结果依次为Cr>Hg >Pb >Cu >Zn >Cd。污土清灌和污水直接灌溉均影响盆栽水稻的正常生长 ,其中污染土壤持续污灌可导致部分秧苗死亡
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研究了辽宁沈阳地区人工林杨树细根及林下草本植物根系的N循环、积累和动态变化特征 .结果表明 ,杨树人工林分条件下活细根中N储量为 2 0 .3kg·hm-2 ,净积累量 10kg·hm-2 ,吸收量 14 .7kg·hm-2 ,年存留量和归还量分别为 9.6和 5 .1kg·hm-2 .周转期 4年 .整个生长季节杨树细根中N含量与土壤中水解N、NH3 N无明显相关 .杨树细根中N浓度与活细根生物量的变化趋势大体一致 ,两者呈显著正相关 .根据杨树活细根中N含量可以估测杨树活细根生物量 .该林分下的草本植物根系主要吸收NH3 N ,草根中N含量浓度变化与土壤中NH3 N的变化趋势相同 ,两者呈显著正相关
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首次报导了辽宁医巫闾山自然保护区的苔藓植物 ,计 2 8科 31属 1 2 9种 ,其中东北地区新记录 3种 ,辽宁省新记录 1种 ,就其在保护区的分布特征、区系成分和地理分布进行分析讨论。
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针对辽宁省章古台地区樟子松人工固沙林出现的衰退枯死现象 ,系统地研究了樟子松人工固沙林衰退的主要特征 .结果表明 ,衰退的樟子松人工固沙林外貌景观呈灰绿色 ,针叶纤细 ,开花结实率低 ,平均单株球果数量为 10 4~ 16 5个 ,成熟种子千粒重为 6 96~ 7 39g ,种子空粒、涩粒较多 .生长季内 2年生针叶营养元素季节变化规律相似 ,但N、P含量下降 ,K含量明显增高 ,表明养分循环失调 ;衰退林分 2年生针叶叶绿素含量较高 ,健康林分 1年生较高且增幅较大 .松枯梢病的侵害是樟子松人工固沙林衰退的最明显标志 .林分衰退后 ,树高和胸径生长量下降明显 ,林分胸径分布结构“左移”(径级小的株数增多 ) ,衰弱 (亡 )木数量增加了 15 9%~ 2 7 2 % ;根量分别减少了 2 2 9%~ 2 8 9% ,其中吸收根减少量最大
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Polyporus moluccensis was newly reported from Hainan Province,Southern China,and its illustrated description was given according to the Chinese specimens.Macroscopically it resembled Polyporus tenuiculus(Beauv.) Fr.,but differed by its smaller basidiospores(5.9~8 × 2.3~3.2 μm vs 8.9~11 × 2.9~4 μm),and by having cystidioles.Polyporus moluccensis grew on rotten angiosperm wood and caused a white rot.
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中文摘要 Ⅰ 慢性阿片类物质滥用对空间认知功能的影响本章首先对成瘾的神经生物学机制进行综述,然后介绍我的实验研究内容,实验目的是探讨海马在阿片类成瘾中的作用,及阿片类物质滥用对空间认知功能的影响。实验1采用单细胞记录技术,记录自由活动大鼠在慢性吗啡给予后戒断期间海马CA1区神经元发放频率,比较其在吗啡相关环境(阳性环境)及无关环境(阴性环境)中神经元发放频率的变化,且比较神经元发放变化率在各组间的差异。实验2检测了在海洛因戒断初期海洛因依赖者的地图/图标跟随及地图/图标工作记忆的能力。实验3采用Y迷宫行为范式检测在戒断不同时期,慢性吗啡给予对小鼠Y迷宫空间识别能力的影响。实验结果如下:实验1:吗啡戒断后,大鼠海马CA1区部分神经元在阳性环境及阴性环境中的发放率有显著性差异,这些神经元分为两类:Ⅰ类神经元在阳性环境中发放频率高于在阴性环境,Ⅱ类神经元在阳性环境中发放频率低于在阴性环境,其中吗啡组的Ⅱ类神经元发放变化率与盐水组相比存在显著性差异。实验2:海洛因依赖者,尤其女性海洛因依赖者,在地图跟随及地图/图标工作记忆中的成绩明显低于正常被试。实验3:在吗啡戒断第2天、第9天、第19天,小鼠Y迷宫空间识别记忆能力均受到损伤。以上实验结果表明,海马神经元在吗啡相关环境与无关环境中发放频率不同,从而编码了环境刺激与药物经历相关的记忆,在阿片类药物成瘾中起到一定作用;以及阿片类物质滥用损伤了大脑空间认知功能。 Ⅱ 嗅觉系统与吗啡成瘾的相互作用本章首先对嗅觉系统的功能及脑疾病引起嗅觉功能异常进行了综述,然后介绍我的实验研究内容,实验目的是探讨嗅觉系统在吗啡成瘾过程中的作用,及慢性吗啡给予对嗅觉功能的影响。实验1:利用条件化位置偏好模型(CPP),研究气味线索对吗啡依赖及渴求的影响。结果发现,单一嗅觉刺激使小鼠建立条件化位置偏好,形成吗啡依赖。当改变外界环境,动物进入完全新异的环境,依然寻求与吗啡相关的气味线索,说明吗啡相关气味线索能有效诱发小鼠对吗啡的渴求。实验2:研究短期及长期吗啡给予后小鼠嗅觉功能的变化。结果发现, 4天或21天的吗啡给予导致小鼠嗅觉敏感度降低(嗅觉阈值升高),而嗅觉辨别能力没有显著影响。小鼠嗅觉记忆能力受到损伤,随着吗啡给予时间的延长,这种记忆损伤更加明显。我们的实验表明嗅觉系统在吗啡依赖及渴求过程起到非常重要的作用,吗啡成瘾导致部分嗅觉功能的损伤。与药物相关的环境线索是诱发渴求及复吸的原因之一,因此,至少在啮齿类动物模型上,用嗅觉刺激作为药物相关的环境线索来研究渴求及复吸的机制,可能是较好的研究方法。
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In this study, we investigated the electroluminescence (EL) mechanisms and processes of hole block material in the multilayer devices with Eu(TTA)(3)phen (TTA = thenoyltrifluoroacetone, phen = 1,10-phenanthroline) doped CBP (4,4'-N,N'-dicarbazolebiphenyl) as the light-emitting layer (EML). First, the hole block ability of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) was experimentally confirmed by comparing the EL spectra. With increasing hole injection, BCP emission emerges and increases gradually due to the increasing hole penetration from EML into the hole block layer (HBL).
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Nanocrystalline LaOCl:Tb3+/Sm3+ phosphors were synthesized by a Pechini-type sol-gel process. Under UV and electron-beam excitation, LaOCl:Tb3+/Sm3+ show the characteristic emission of Tb3+ (D-5(3,4) -> F-7(6), ... (2)) and Sm3+ ((4)G(5/2) -> H-6(5/2),(7/2),(9/2)), respectively. In particular, the cathodoluminescence (CL) color of LaOCl:Tb3+ can be tuned from blue to green by changing Tb3+-doped concentration, and their CL intensities (brightness) are higher than those of commercial products Y2SiO5:Ce3+ and ZnO:Zn, respectively. White CL can be realized by codoping with Tb3+ and Sm3+ in a single-phase LaOCl host. The obtained white light is very close to the standard white light. These phosphors are promising for application in field-emission displays.
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LaInO3: Sm3+, LaInO3: Pr3+ and LaInO3: Tb3+ phosphors were prepared through a Pechini-type sol-gel process. X-ray diffraction, field emission scanning electron microscopy, photoluminescence, and cathodoluminescence (CL) spectra were utilized to characterize the synthesized phosphors. XRD results reveal that the pure LaInO3 phase can also be obtained at 700 degrees C. FE-SEM images indicate that the LaInO3: Sm3+, LaInO3: Pr3+ and LaInO3: Tb3+ phosphors are composed of aggregated spherical particles with sizes around 80-120 nm. Under the excitation of ultraviolet light and low voltage electron beams (1-5 kV), the LaInO3: Sm3+, LaInO3: Pr3+ and LaInO3: Tb3+ phosphors show the characteristic emissions of Sm3+ ((4)G(5/2)-H-6(5/2,7/2,9/2) transitions, yellow), Pr3+ (P-3(0)-H-3(4), P-3(1)-H-3(5), D-1(2)-H-3(4) and P-3(0)-F-3(2) transitions, blue-green) and Tb3+ (D-5(4)-F-7(6.5,4.3) transitions, green) respectively. The corresponding luminescence mechanisms are discussed. These phosphors have potential applications in field emission displays.
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By incorporating two phosphorescent dyes, namely, iridium(III)[bis(4,6-difluorophenyl)-pyridinato-N,C-2']picolinate (Flrpic) for blue emission and bis(2-(9,9-diethyl-9H-fluoren-2-yl)-1-phenyl-1 H-benzoimidazol-N,C-3) iridium(acetylacetonate) ((fbi)(2)Ir(acac)) for orange emission, into a single-energy well-like emissive layer, an extremely high-efficiency white organic light-emitting diode (WOLED) with excellent color stability is demonstrated. This device can achieve a peak forward-viewing power efficiency of 42.5 lm W-1, corresponding to an external quantum efficiency (EQE) of 19.3% and a current efficiency of 52.8 cd A(-1). Systematic studies of the dopants, host and dopant-doped host films in terms of photophysical properties (including absorption, photoluminescence, and excitation spectra), transient photoluminescence, current density-voltage characteristics, and temperature-dependent electroluminescence spectra are subsequently performed, from which it is concluded that the emission natures of Flrpic and (fbi)(2)Ir(acac) are, respectively, host-guest energy transfer and a direct exciton formation process. These two parallel pathways serve to channel the overall excitons to both dopants, greatly reducing unfavorable energy losses.
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By introducing tungsten oxide (WO3) doped N,N-'-di(naphthalen-1-yl)-N,N-'-diphenyl-benzidine (NPB) hole injection layer, the great improvement in device efficiency and the organic film morphology stability at high temperature were realized for organic light-emitting diodes (OLEDs). The detailed investigations on the improvement mechanism by optical, electric, and film morphology properties were presented. The experimental results clearly demonstrated that using WO3 doped NPB as the hole injection layer in OLEDs not only reduced the hole injection barrier and enhanced the transport property, leading to low operational voltage and high efficiency, but also improved organic film morphology stability, which should be related to the device stability. It could be seen that due to the utilization of WO3 doped NPB hole injection layer in NPB/tris (8-quinolinolato) aluminum (Alq(3))-based device, the maximum efficiency reached 6.1 cd A(-1) and 4.8 lm W-1, which were much higher than 4.5 cd A(-1) and 1.1 lm W-1 of NPB/Alq(3) device without hole injection layer. The device with WO3 doped NPB hole injection layer yet gave high efficiency of 6.1 cd A(-1) (2.9 lm W-1) even though the device was fabricated at substrate temperature of 80 degrees C.
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By utilizing 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline:Li/MoO3 as an effective charge generation layer (CGL), we extend our recently demonstrated single-emitting-layer white organic light-emitting diode (WOLED) to realize an extremely high-efficiency tandem WOLED. This stacked device achieves maximum forward viewing current efficiency of 110.9 cd/A and external quantum efficiency of 43.3% at 1 mu A/cm(2) and emits stable white light with Commission Internationale de L'Eclairage coordinates of (0.34, 0.41) at 16 V. It is noted that the combination of effective single units and CGL is key prerequisite for realizing high-performance tandem WOLEDs.