碱

These dendritic NOBIN derived Schiff base ligands have been applied to titanium catalyzed hetero-Diels-Alder reaction of Danishefshy's diene and aldehydes, affording the corresponding 2-substituted 2, 3-dihydro-4H-pyran-4-one in quantitative yields and excellent enantioselectivities (up to 97. 2%ee). Comparing the reactivities and enantioselectivities of reaction catalyzed by the titanium complexes of these Schiff base ligands, it was found that a series of ligands L〓 were superior to the other three series of ligands L〓, L〓 and L〓, a significant positive NLE and a dendrimer effect existed in the L〓 dendritic catalyst system. The disposition of the dendritic wedges and the dendron size in the ligands were observed to have a significant impact on the enantioselectivity of the reaction.

NOBIN衍生的树枝状大分子希夫碱手性配体与钛形成的配合物在催化不对称杂Diels-Alder反应中的应用将得到的四个系列NOBIN衍生的树枝状希夫碱三齿手性配体与四异丙氧基钛形成的配合物用于催化Danishefsky's diene与醛的不对称杂Diels-Alder反应，通过反应条件的优化，获得了定量的收率和最高达97.2％ee值的对映选择性；考察了这四个系列NOBIN衍生的树枝状希夫碱钛配合物的催化活性和对映选择性，结果发现它们的活性次序依次为L〓≈L〓＞L〓＞L〓，对映选择性次序依次为L〓＞L〓＞L〓＞L〓。

Bimolecular rate constants to DDVP, eserine, omethoate, methomyl and propoxur of resistant housefly were lower than that of the susceptible strain, which were 26.51, 7.80, 7.70,12.54 and 22.48 times, respectively, in comparison with the susceptible strain, indicating the enzyme was insensitive to these insecticides.

不同浓度的DDVP、毒扁豆碱和残杀威对家蝇AChE的抑制作用表明，随着DDVP和残杀威浓度升高，AChE的残存活性降低较多，抗性家蝇AChE的残存活性高于敏感家蝇，而随着毒扁豆碱浓度的增加，AChE残存活性降低较少，并且当毒扁豆碱浓度很低时，在一定范围内，敏感家蝇AChE的残存活性高于抗性家蝇。

These specific cDNAs and DNAwere subcloned into vector for sequencing.The sequencing results demonstrated thatthe specific cDNA from P.chinensis eyestalk consists of 203 base pairs,and all thespecific cDNAs from the shrimps T.curvirostris,P.stylirostris and the crab E.sinensis consist of 215 base pairs.

分别将这些片段亚克隆到载体中进行测序，测得中国对虾特异性cDNA片段由203个碱基组成，中华绒螯蟹、鹰爪虾、蓝对虾的特异性cDNA片段及蓝对虾的特异性DNA片段由215个碱基组成，其中蓝对虾的特异性cDNA与由蓝对虾的基因组DNA扩增得到的特异性DNA片段的碱基序列几乎完全相同。

From the point of view of geobotany, with the method of correlative factors of growth of plants, a countrywide theoretic ecological division was done for the introduction of Camptotheca acuminata and three kinds of areas of ecological preferent zone, ecological adaptive zone and ecological unadaptable zone were divided. With the theory of synecology, the characteristic on environment, constitution, life form spectrum, diversity, similarity of plots of communities were researched. Applying the method of species association, discrete distribution, indensity index, fractal geometry, etc. to research relations between the species of the communities, space distribution of Camptotheca acuminata, structure of age of Camptotheca acuminata, in different communities. Using the theories of autoecology, distibutons of seeds on land and growth of seedlings in vertical and horizontal directions, biomass of organ of Camptotheca acuminata were analyzed. On the opinions of conservation biology, the external and internal factors impressing Camptotheca acuminata were analyzed to research the mechanism of the endangered species, and with using of CTM Model, the future development direction of Camptotheca acuminata in different communities were forecasted, and. Standing on the position of resources ecology, discussing the regularity of camptothein in Camptotheca acuminata of different sites and seeding of different resources, also the the derive technics of camptothecin.

本文从地植物学的角度，运用植物生长相关因子法，对我国喜树资源的生态适宜区进行了划分，理论上确定了我国的喜树的引种栽培的最适生活区域、生态适宜区域和不适宜生活区域；从群落生态学的角度，对野生喜树所在的典型群落的群落环境、群落组成、群落生活型谱、群落的物种多样性特点、群落样地间相似性进行了研究；从种群生态学的角度，运用种间联结性、离散分布模型、聚集强度指数、分析几何等分析手段，对野生喜树所在典型群落间的种间关系、喜树的空间分布格局、年龄结构等进行了分析；从个体生态学的角度，对不同年龄组的喜树的种子的散落的垂直分布、水平分布、时间分布及种子发芽率和千里重等特点、不同种源的人工喜树苗期特点、喜树的高生长和茎生长特点、喜树的器官生物量特点进行了研究；从保护生物学的角度，对野生喜树的濒危的内部因素和外部因素进行了探讨，并运用CTM模型对不同群落中野生喜树的种群趋势进行了预测；从资源生态学的角度，对我国地理环境下喜树中喜树碱含量的地理分布规律、不同种源的喜树幼苗中喜树碱含量变化规律进行了研究，并对喜树碱的提取工艺进行了探讨。

Cephalotaxine ester of 2-oxo-6-methylheptanoic acid was treated with lithium diisopropylamide and Me O-(1-methoxyisopropyl)glycolate to give a mixture of homoisoharringtonine and its stereoisomers with 56% yield. The four stereoisomers separated by TLC showed identical mass spectra and almost superimposed IR but with different 1H NMR spectra. The configuration of the 2'-C and 3'-C of the four isomers were postulated based upon their 1H NMR spectra as compared with the 1H NMR spectra of isoharringtonine and its stereoisomers.

2-氧代-6-甲基庚酰基三尖杉碱(3)与0-(1-甲氧基异丙基)羟基乙酸甲酯(4)在强碱性试剂二异丙胺锂存在下，起亲核加成反应，反应中间体5在室温用酸性丙酮水解，得到一种新的三尖杉酯类生物碱一一高异三尖杉酯碱(6c)及其立体异构体(6a、6b、6d)的混合物，产率56%、通过制备薄层层析分得这四个立体异构体，它们的1H NMR和异三尖杉酯碱及其立体异构体的1H NMR类似，推定了它们的绝对构型。

Hydrastine(97.7%) was obtained with extracted rate 65%by extracting the Goldenseal with mixed Solvent;Berberine hydrochloride (99.9%) was obtained by adding hydrochloride acid to alcohol (alcohol∶H 2O=1∶1) solution of the extract and Hydrastine (99.5%) was gained by CLC method with the yield 1%.

原药材用混合溶剂直接提取分离，可得到含北美黄连碱 97.7%的结晶体，提取率达 6 5%；提取物经醇水溶解、酸化，可直接获得小檗碱盐酸盐结晶，纯度达到 99.9%；用柱色谱法，可得到 99.5%的北美黄连碱，收率约 1

Because we will control the content of alkali in clinker, although the clinkerability of high silicon low alkali gritstone composition is insufficient a little, but it"s a good composition. The best control parameters of high silicon low alkali gritstone composition are: adopting "three-high rates composition, in a specific way, three rates should choose KH:0.9, SM:2.6, IM:1.6, and control the granularity of raw material is 280m /kg.

从控制熟料中碱含量的角度出发，高硅低碱砂岩配料虽然易烧性略差，但仍不失为一个好的配料方案；高硅低碱砂岩配料方案的最佳控制参数为：采用"三高"配方，熟料的饱和比0.9，熟料的硅酸率2.6，熟料的铝氧率1.6，生料的细度控制在280m~2／kg。

Kowaltowski AJ, Vercesi AE. Mitochondrial damage induced by conditions of oxidative stress ［J］. Free Radic Biol Med, 1999,26(3-4):463～471.［6］Hauptmann N, Grimsby J, Shih JC.

4.1 碱基切除修复碱基切除修复被证实是通过一种DNA糖基酶，这种酶可以识别损伤的碱基，裂解其糖苷键。

Trev. obtained by different extracting methods and investigate the amount of alkaloids and the content of Hup A from different parts of the plants and from different places.

目的 考察蛇足石杉不同产地、不同部位中石杉碱甲和总碱含量；比较不同提取方法对石杉碱甲含量的影响。

Is for the airplane, above the clouds so high sowing and sing, like a big bird in sky B is for a bunny, but it doesn't cut his tail, he goes cipety hup hup hup, a longer bunny trail.

是上述的云雾，使飞机，播种和唱歌，像一个大鸟在天空 B是一个兔子，但它不切断了他的尾巴，他就会cipety石杉碱甲石杉碱甲石杉碱甲，较长的兔子痕迹。

Plunder melds and run with this jewel!

掠夺melds和运行与此宝石！

My dream is to be a crazy growing tree and extend at the edge between the city and the forest.

此刻，也许正是在通往天国的路上，我体验着这白色的晕旋。