双位

THE FIRST TOTAL SYNTHESIS OF TAXAMAIRIN B Taxamairin B, representive of rare naturally-occuring rearrang-ed 9(10→20)-abeo-8, 11, 13-triene diterpenoids, has been firstsynthesized by a eleven-step route in an overall yield of 8.19%,starting from commercially available catechol and 1,3-cyclohexan-dione. The improved Friedel-Crafts annulation, thermodynamicallycontrolled-geminal pairing methylation, the selective oxidation ofallyl group and the selective reduction of the less-hindrancecarbon-carbon double bond are the key steps.

二。美丽红豆杉素B的全合成研究 1，美丽红豆杉素B的首次全合成以价廉，易得的邻苯二酚和1，3-环己二酮为原料，经过改良的Friedel-Crafts烷基化反应，热力学控制的α，β-不饱和酮结构的α一位双烷基化，烯丙位的选择性氧化，以及选择性还原位阻较小的碳碳双键等十一步反应，以8.19％的总收率首次完成了美丽红豆杉素B的全合成。

Their motion asymmetry supported the idea of close correlation between motion perception symmetry and binocularity.

三位双上旋肌麻痹，一位视神经重度发育不全，一位早产儿网膜症，两位合并水平及垂直斜视，一位角膜彼得氏异常和一位网膜先天缺损，他们自出生起就没有发育双眼视觉的机会，他们不对称的运动觉支持了运动觉对称性和双眼视觉之间相关性的理论。

We propose a kind of 3D eddy current boundary value problems in the form of two component vector potential and approve the validity the potential in some situations.

本文提出三维涡流场的双分量向量位形式的边值问题，并证明了双分量向量位在一定条件下的适用性。

Mn-complexes in which Mn atom ligand with the N atom within ligand can stimulate the recovery of electron transfer and oxygen evolution. The trinuclear Mn-complex is extremely sensitive to the addition of CaCl2. It is suggested that there is an interaction between Ca2 and carboxyl within the trinuclear Mn-complex during photoactivation and this interaction benefits the ligation of Mn atom to the apo-WOC and form an active WOC. Binuclear MnMn complex shows slightly higher efficiency than binuclear MnMn complex in restoration of O2 evolution activity. It is suggested from our results that recovery of electron transport and O2 evolution with synthetic Mn-complexes is affected by different factors. Cl- can stimulate the reconstitution of WOC at the concentration of over 100mM;the maximal recovery of O2 evolution activity requires the presence of CaCl2 and 33 kDa protein polypeptide together. Bicarbonate can stimulate the reconstitution of WOC.

锰配合物中锰原子与配体中的氮原子配位连接时，能显著恢复电子传递活性和放氧活性；三核锰化合物在重组时对CaCl2的存在非常敏感，我们认为Ca2 与三核锰化合物中的羧基之间存在一定的相互作用，而这种作用有助于锰原子的光配位进而使三核锰化合物易于组装成有活性的水氧化复合物：双核锰化合物MnMn比双核锰化合物MnMn在恢复放氧活性方面更有效；影响锰化合物电子传递能力恢复的因素与影响锰化合物放氧活性恢复的因素不同；在锰蔟重组过程中，氯离子的浓度必须在100mM以上，才能有效进行光重组；最大光重组效率的获得必须有钙离子和33kDa多肽同时存在；碳酸氢根离子促进锰化合物与去锰光系统II的光组装。

It isconfirmed by ~1H NMR,~(13)C NMR and X-ray crystallographic analysis that complexes 60-63are monopyridine complexes and show distorted square pyramid geometries; complexes 64and 65 are bispyridine complexes and show pseudo-octahedral geometries, where twopyridine ligands are in cis arrangement and trans to the NHC and the benzylidene ligandrespectively, the bond length between ruthenium and pyridine ligand trans to the benzylideneligand is 16 pm longer than the bond length between ruthenium and pyridine ligand trans tothe NHC ligand.

1H NMR、~(13)C NMR及X射线单晶衍射分析证明，配合物60-63是单吡啶衍生物配位的钌卡宾配合物，具有变形的四方锥构型；配合物64、65为双吡啶衍生物配位的钌卡宾配合物，具有变形的八面体构型，其中两个顺式配位的吡啶衍生物分别处于氮杂环卡宾和苯亚甲基的反位，处于苯亚甲基反位的吡啶衍生物对应的钌-氮键长要比处于氮杂环卡宾反位的长出16 pm。

For the first tin atom, it appears to be seven-coordinated with a distorted pentagonal bipyramid geometry, and the other is five-coordinated with a distorted trigonal bipyramidal geometry.

其中一类锡原子呈七配位畸变五角双锥构型，另一类呈七配位畸变三角双锥构型。

There exists isomorphous replacement in the rutile structure, and the most prominent feature is the average content of oxides, being 1.22%, 0.39%, 0.35% and 0.22% for V 2O 5, Fe 2O 3, ZnO and CuO respectively. They substitute Ti 4+ in octahedra. The valence of V is 5, and its polyhedron is trigonal bipyramid, which causes the lattice distortion, breaks the raw octahedron symmetry into square bipyramid, and produces the microstrains in the structure.

天然含钒金红石平均含V2O5可达1.22％，Fe2O30.39％，ZnO0.35％，CuO0.22％，这些金属离子可替代八面体中Ti^4 。V以5价形式存在，配位多面体呈三方双锥，其在晶格内部对Ti的替代导致晶格畸变，打破了配位多面体原有的八面体对称而呈四方双锥的几何形态，并产生结构微应力。

Results:Under the laparoscopy,1 patient had a normal pelvis,the other 9 persons got conglutinant pelvis(7 were caused by chronic pelvic inflammation,1 by operation,1 by endometriosis),3 got wide conglutination between the back wall of uterus and rectum,depression of rectum disappeared;1 got pelvic inflammatory cyst;4 got endometriosis,and one of which got bilateral ovarian cyst and bilateral ovarian small teratoma.

结果：1例盆腔正常；9例盆腔粘连（慢性盆腔炎引起7例，手术引起1例，子宫内膜异位引起1例），其中3例子宫后壁与直肠广泛粘连，直肠窝消失；1例盆腔炎症包块；4例子宫内膜异位，其中1例双侧卵巢小巧克力囊肿合并双侧卵巢小畸胎瘤。

Crystal structural analysis reveals that, because water molecules bond to Cu atoms, the dhbd ligand can only adopt a hydroxyl oxygen atom to bridge two reversed U-shaped subunits into a novel centrosymmetric dual-U-shaped tetranuclear Cu structure. Each U-shaped frame consists of two crystallographically distinct Cu atoms, two dpphen ligands and one coordinated water molecule.

晶体结构分析表明，由于水的配位阻断， 2，3-二羟基丁二酸根仅通过单羟基氧桥联两个U形双核亚单元形成具有一个对称中心的双U形四核结构，其中U型亚单元包含晶体学上不对称的2个Cu原子、1个2，3-二羟基丁二酸根、2个4，7-二苯基-1，10-邻菲咯啉和1个配位H2O分子。

The more the number of hydroxyl substitution in phenyl ring, the better the ability of scavenging DPPH free radical. That is, trihydroxy is better than dihydroxy, and dihydroxy is better than monohydroxy. Moreover, when the polyhydroxy exists in phenyl ring and it is ortho-position or para-position, the ability of scavenging DPPH free radical is better too.

当苯甲醯基的苯环上羟基取代数量越多，其清除DPPH自由基的能力越好，三羟基效果优於双羟基、单羟基，双羟基效果优於单羟基；而苯甲醯基苯环上若为多羟基且羟基的位置为邻位或对位的关系时，其在清除DPPH自由基的能力较佳。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。