67 resultados para C ... f, B ... n.
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以1,2--3,4-二氢咔唑-9-乙基氯甲酸酯(BCEOC),Hypersil BDS C18 (4.6 200 mm, 5 m)反相色谱柱上,390 nm(333 nm),20种氨基酸标准品衍生物的分离检测.20种组分的线性范围为51.6 fmol～105.6 pmol,0.9995;检出限为6.3～177.6 fmol (S/N=3:1).经柱后串联质谱电喷雾电离源(ESI Source),并以酪氨酸(Tyr).对ABC三组(A:安静对照组;B:运动力竭即刻组;C:力竭恢复12 h ) 24只大鼠血浆中氨基酸的定量测定结果表明,;12 h .,为大鼠血浆中氨基酸的测定提供了一种新方法
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本文详细讨论了世界芨芨草属的地理分布等问题。1.231,分为52.属的地理分布,62°(羽茅、毛颖芨芨草),26°(),分布最低的海拔记录为120m(),4600m()3.5(芨芨草组,,,新芨芨草组,)5个组的分布格局。4.-土兰种类（18/2414/2417种，横断山脉地区、华北地区和唐古特地区种数最丰富（109种）。5.A）从种的分布格局分析可见，横断山脉地区北部、唐古特地区东部和华北地区西部的交汇地是芨芨草属分布中心。（BCa)b)从横断山脉向西北经祁连山、天山、塔里木盆地西侧山地，抵吉尔吉斯斯坦伊塞克湖；c)D-生态特征和生活型。
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In the alpine region of the Tibetan Plateau, five perennial grass cultivars, Bromus inermis (B), Elymus nutans (E), Clinelymus nutans (C), Agropyron cristatum (A), and Poa crymophila (P) were combined into nine communities with different compositions and ratios, B+C, E+A, B+E+A, E+B+C,C+E+A,B+E+C+A,B+C+A+P,B+E+A+P and E+C+A+P. Each combination was sown in six 10 X 10 m plots with three hand-weeded plots and three natural-growing plots in a completely randomised design in 1998. A field experiment studied the performance of these perennial grass combinations under the competitive interference of annual weeds in 3 consecutive years from 1998 to 2000. The results showed that annual weeds occupied more space and suppressed the growth of the grasses due to earlier germination and quicker growth in the establishment year, but this pattern changed in the second and third years. Leaf area indexes (LAIs) of grasses were greatly decreased by the competitive interference of weeds, and the negative effect of weeds on LAIs of grasses declined and stabilised in the second and third years. E+B+C, B+E+C+A, and B+E+A+P possessed relatively higher LAIs (P < 0.05) among all grass combinations and their LAIs were close to five when the competitive interference of weeds was removed. Grasses were competitively inferior to weeds in the establishment year, although their competitive ability (aggressivities) increased throughout the growing season. In the second and third years, grasses were competitively superior to weeds, and their competitive ability decreased from May until August and increased in September. Dry matter (DM) yields of grasses were reduced by 29.8-74.1% in the establishment year, 11.0-64.9% in the second year, and 16.0-55.8% in the third year by the competitive interference of weeds. B+E+C+A and B+E+A+P can produce around 14 t/ha of DM yields, significantly higher (P < 0.05) than the production of the other grass combinations in the second and third years after the competitive interference of weeds was removed. It was preliminarily concluded that removal of competitive interference of weeds increased the LAIs of all grass swards and improved the light interception of grasses, thus promoting the production of perennial grass pastures. The germination stage of the grasses in the establishment year was the critical period for weeding and suppression of weeds should occur at an early stage of plant growth. The grass combinations of B+E+C+A and B+E+A+P were productive and can be extensively established in the alpine regions of the Tibetan Plateau. Two or three growing seasons will be needed before determining success of establishment of grass mixtures under the alpine conditions of the Tibetan Plateau.
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“CIMS”来源于国家863高技术计划，它是“CIMS”的一个重要组成部分，也是柔性制造系统多级管理和控制”1. TD法。通过TD2. CIMS特点，针对具有同步特征的子任务，本文提出“”G-B-C法。通过G-B-C3. PC机上用C语言实现，实验证明，本文所提思想和方法是可行的，有效的。
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The main research area of this thesis is Jiyang Depression in the Bohaiwan Basin and its southern margin. The object formation is Ordovician carbonate. The research is based on the outcrop observation and measurement of Ordovician carbonate and the drilling data of the oilfield. The internal reservoir characteristics of carbonate buried hill and its distribution were studied by comprehensive methods of sedimentology, reservoir geology and structural geology and technics of cathodoluminescence(CL)3electron microprobe,casting and C O isotope analysis etc. The influence depth of paleokarst facies formed during the Paleozoic is discriminated as 36-84m. The sollution porosity is well developed in paleokarst facies of Ordovician carbonate and is an important type of internal reservoir of buried hill. It may be infered that the fractures may be formed mainly during the Mesozoic and Cenozoic, they were not developed during the early Paleozoic when only micro-fractures might be created. The carbon and oxigen isotope analysis shows that the calcite cements in the fractures of Ordovician carbonate and secondary solution pores were related with meteoric water and three stages of fractures were divided. The reservoir space of Ordovician carbonate are mainly secondary porosity, cavern and fracture. The development of structural fracture was controlled by the lithology and tectonic background. More fractures exist in dolomite than that in limestone. There are also more fractures near the fault and the axis of fold. The development of porous reservoir is mainly controlled by the lithology and diagenesis, especially dolomitization and dissolution. It also results in the heterogeneity vertically. So the lithology is the basic factor for the forming of internal reservoir of buried hill and the tectogenesis and diagenesis are key factors to improve it. The porosity in carbonate might experienced solution-cementation-resolution or recementation. The porosity evolution history was a kind of historical dynamic equilibrium. The internal reservoir of Ordovician carbonate is the comprehensive result of constructive and/or destructive diagenesis. The worm's eye maps of the early Paleozoic and middle-upper Proterozoic were plotted. It was inferred that the paleostress field evoluted from NNW to NW during the Mesozoic and Cenozoic. Three types of buried hills can be divided: C-P/Pzi, Mz/ Pzi and E/ Pzi. The unconformity of the buried hill of E/ Pzi type, comparatively, was formed and reconstructed latestly, t he p orous r eservoir c ould b e w ell p reseved. T his c ondition w as v ery favorable t o t he migration and accumulation of oil and gas and could form upstanding association of source-reservoir-cap rocks. The buried hills of Mz/ Pzi and C-P/Pz] type were took second place.
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利用三维荧光光谱研究了太阳辐射对溶解有机质(DOM),太阳辐射使DOM的荧光发射光谱强度减弱。在三维荧光光谱图中,A,C,A,B,C,CExmax/λEmmax,原始样品荧光峰位置出现在λEx/Em=275/500nm,Ex/λEm=245/450nm和310/450nm。太阳辐射对DOM中不同荧光组分的光降解速率存在差异,AC的比值r(A,C)随太阳辐射时间的变化趋势得知,C
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文章以金川和红原两组泥炭纤维素Δ13C ,5 000 ,西太平洋副热带高压的活动可分为4 ,即西太平洋副热带高压位置在28002200 B. C. ,2200600 B. C. ,600 B. C. 1200 A.D. 期间在北进与南移之间频繁波动,1200 ～1900A. D. ,1900A. D. 起西太平洋副热带高压的活动似乎又开始一个新的偏南阶段,
