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81.
Abstract— The photobehavior of the ciliates Climacostomuum virens, Euplotes daidaleos and Paramecium bursaria associated with endosymbiotic green algae ( Chlorella sp.) was compared with that of aposymbiotic ciliates (ciliates free of algae) and with the always aposymbiotic Paramecium arcticum . The aposymbiotic ciliates showed step-up photophobic responses. The responses were more frequent and occurred at lower light intensities when the organisms contained endosymbiotic algae. In contrast, step-down photophobic responses and photoaccumulations, as well as photokinesis, were never observed in aposymbiotic cells. These responses could be found only in ciliates when endosymbionts were present with the exception of C. virens , which showed none of these photoresponses. 相似文献
82.
On Trichlorophosphazo Compounds from Nitriles. III. The Reaction between Acrylonitrile and PCl3. The reaction of PCl3 with acrylonitrile at higher temperatures gives CH2Cl? CCl2? CCl2? N? PCl3 ( II ). On pyrolysis of (II), CH2Cl? CCl2? CN (IV) is form- ed. Treatment of (II) with SO, results in CHzCL? CCl2? CCl?N-P(0)Cl2 ( III ). At lower temperatures and/or in the presence of PCl3, acrylonitrile reacts with PCl3 to give the cis/ trans isomers VIa and VIb . 相似文献
83.
Me3B3N3H3Cr(CO)3 has been obtained by ring-ligand exchange starting from Et3B3N3Me3Cr(CO)3 and Me3B3N3H3. The new compound has been characterised by means of their IR, NMR, UV and mass spectroscopic data. 相似文献
84.
Open- and closed-shell states in few-particle quantum mechanics. II. Classification of atomic states
The system developed in the first paper of this series for the classification of states as open- or closed-shed type is applied to atomic states. These may be classified in the isoelectronic limit (Z → ∞) from knowledge of the true wave function in this limit. One-matrix occupation numbers are tabulated for a number of states of the first-row atoms in the limit Z → ∞ and the states classified. A classification for finite Z is possible in the framework of the Z-dependent perturbation theory by use of a thoerem for the stability of a closed-shed with respect to small perturbations. Such a stability does not hold in general for open-shel states. 相似文献
85.
The crystal structures of (Ph3PCl)2[Cu3Cl8] (1) (triclinic, space group P1, a = 9.480(6) A, b = 10.243(8) A, c = 11.232(6) A, alpha = 86.76(4) degrees, beta = 66.62(5) degrees, gamma = 83.92(4) degrees, Z = 1) and (Ph3PMe)2[Cu3Br8] (2) (triclinic, space group P1, a = 9.795(4) A, b = 10.472(4) A, c = 11.392(4) A, alpha = 86.67(3) degrees, beta = 66.67(3)degrees, gamma = 83.14(3) degrees, Z = 1), reported here, demonstrate a new supramolecular motif for cations of the type Ph3PY+ where Y is CH3 or Cl. The crystals contain columns of cations propagated by alternating 6-fold phenyl embraces (6PE) and pseudo-6PE: the pseudo-6PE described here contains four phenyl rings and two hetero groups (Cl or CH3), and is symbolized as 4P2Y. The zigzag sequence of cations engaged in ...6P...4P2Y...6P...4P2Y... is similar to the zigzag chain of infinite 6-fold phenyl embraces (ZZI6PE) frequently adopted by Ph4P+ cations in crystals. One-dimensionally nonmolecular anion chains with repeat unit [Cu3X8] run parallel to and between the columns of cations. The coordination geometry in the [Cu3X8(2-)]1 to infinity chain has not been observed in crystals with other cations, and it is postulated that the attractive interactions between cations in the pseudo-ZZI6PE crystal supramolecular motif control the geometry of the anions through the requirement for commensurability of cation columns and anion chains. 相似文献
86.
87.
A simple semiconductor gas sensor (TGS 812) is used for the on-line measurement and control of indole during the production of l-tryptophan from indole and l-serine with immobilized E. coli cells. Indole is estimated in the reactor gas space. In combination with an automatic indole supply system, a feed-batch process became possible. The indole concentration was monitored and kept within the optimal range (300–600 mg l?1). A simple gas-sensing electrode dipped in the reaction medium provides direct measurement of organic solvents and gases in the liquid. Such a system is suitable for on-line determination of ethanol (10–70 g l?1) during continuous production of ethanol with immobilized yeast cells. 相似文献
88.
The complex [C5H5RhH(C2H4)PMe3]BF4 (I) reacts with NaF and NaCN by deprotonation to give C5H5Rh(PMe3)C2H4 but with NaCl, NaBr and NaI the ethylrhodium compounds C5H5RhC2H5(PMe3)X (II–IV) are obtained. The reactions of I with CO and PPri3 yield the BF4 salts of the cations [C5H5RhH(CO)PMe3]+ and [C5H5RhH(PPri3)PMe3]+ (V, VI), respectively, from which the uncharged complexes C5H5Rh(CO)PMe3 (VII) and C5H5Rh(PPRi3)PMe3 (VIII) are prepared. The carbonyl compound VII is also accessible either from C5H5Rh(CO)2 and PMe3 or from C5H5Rh(PMe3)2 and CO. The reaction of I with ethylene leads to the BF4 salt of the cation [C5H5RhC2H5(PMe3)C2H4]+ (X) which on treatment with PMe3 forms the complex [C5H5RhC2H5(PMe3)C2H4PMe3]BF4 (XI). The compound [C5H5RhH(C2H4)PPri3]BF4 (XII) reacts with NaI by insertion to yield C5H5RhC2H5(PPri3)I (XIII) whereas with PPri3 the salt [C5H5RhH(PPri3)2]BF4 (XIV) is produced. The bis(triisopropylphosphine) complex C5H5Rh(PPri3)2 (XVI) is obtained from XIV and NaH. 相似文献
89.
Total Synthesis of (+)-D-Homoestrone 3-methyl ether A novel total synthesis of (+)-D-homoestrone 3-methyl ether ( 21 ) is described starting from (S)-8a-methyl-3,4,8,8a-tetrahydro-2H, 7H-naphthalene-1,6-dione ( 1 ) as a chiral synthon for the rings C and D. The key step involves alkylation of the derived 3 with m-methoxyphenacyl bromide ( 4 ) as an AB-building block to give the dioxo-secosteroid 5 . Hydrogenation of 5 affords the trans-decalone 11 . As by-products the epimeric cis-decalones 12 and 13 were characterized. Cyclization of 11 leads under kinetic control predominantly to the Δ9(11)-tetraene 14 . Catalytic hydrogenation of 14 and subsequent modification in ring D give the title compound 21 . It was found that 14 and also the derived Δ8-isomer 15a add hydrogen from the α-face of the molecule to an extent of about 80%. The 8α-D-homoestrone derivatives 20a and 23 as well as the 9β-isomers 19a and 22 were characterized. 相似文献
90.
Robert Weis Marcel Kaiser Reto Brun Robert Saf Werner Seebacher 《Monatshefte für Chemie / Chemical Monthly》2006,137(10):1365-1374
Summary. 4-Aminobicyclo[2.2.2]octan-2-ones and -ols showed activity against the causative organisms of East African sleeping sickness
and Malaria tropica. Several imino derivatives of the ketones were more active. Now hydrazono analogues and 3-hydroximino
derivatives of the ketones and alcohols were synthesized. The structures of the obtained isomers were elucidated by NMR spectroscopy.
A single phenylhydrazone exhibited quite good antitrypanosomal activity in the range of already known imino analogues. 相似文献