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991.
We have measured all deuteron analyzing powers ${(A_{y}^{d}, A_{yy}, A_{xx}, A_{xz})}$ for deuteron-proton elastic scattering at 294 MeV/nucleon in order to study the properties of three nucleon forces (3 NFs). Measurement was made at in an angular range of ${\theta_{{\rm c.m.}} = 35.6^{\circ} - 163.0^{\circ}}$ . Obtained data were compared with Faddeev calculations with and without the 3 NFs. At ${\theta_{{\rm c.m.}}\lesssim 120^{\circ}}$ all the data have general agreement with the calculations, while the measured data at ${\theta_{{\rm c.m.}} \gtrsim 120^{\circ}}$ are not explained by any theoretical calculations. These results were consistent with those at 250 MeV/nucleon.  相似文献   
992.
We prove that if R is a semiprime ring and α is a partial action of an infinite cyclic group on R, then R is right Goldie if and only if R[x; α] is right Goldie if and only if R?x; α? is right Goldie, where R[x; α] (R?x; α?) denotes the partial skew (Laurent) polynomial ring over R. In addition, R?x; α? is semiprime while R[x; α] is not necessarily semiprime.  相似文献   
993.
We have used the reprecipitation method and subsequent two‐step imidization to fabricate highly porous polyimide (PI) nanoparticles possessing crater‐like surface pores (depths, diameters: tens of nanometers) from poly(amic acid) (PAA) derivatives in the presence of poly(sodium‐4‐styrenesulfonate) (PSS) as a polyelectrolytic porogen. The porous structures arose presumably through segregative microphase separation of PAA and PSS (i.e. repulsion between PAA and PSS in the presence of a common solvent) and subsequent removal of PSS. The addition of this strong polyelectrolyte improved the degree of porosity of the resulting PI nanoparticles and allowed controllable release of the porogen. The resulting porous PI nanoparticles exhibited a high thermal stability (5% weight loss at temperature 450°C). This technique is suitable for the preparation of novel low‐k materials and their surface‐related applications. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
994.
995.
New manzamine alkaloids, zamamidine C (1), 3,4-dihydro-6-hydroxy-10,11-epoxymanzamine A (2), and 3,4-dihydromanzamine J N-oxide (3), have been isolated from an Okinawan marine sponge Amphimedon species. The structures and stereochemistries of 1-3 were elucidated from the spectroscopic data and chemical derivatization. Zamamidine C (1) is a new manzamine alkaloid possessing a second β-carboline ring via an ethylene unit at N-2 of manzamine D, while 3,4-dihydro-6-hydroxy-10,11-epoxymanzamine A (2) is the first manzamine alkaloid possessing an epoxide ring at C-10 and C-11. Zamamidine C (1) showed significant antitrypanosomal activity against Trypanosoma brucei brucei, the parasite associated with sleeping sickness, and antimalarial activity against Plasmodium falciparum, the causative agent of malaria in vitro.  相似文献   
996.
A new dimeric bromopyrrole alkaloid possessing a benzocyclobutane ring, benzosceptrin C (1), has been isolated from an Okinawan marine sponge of the genus Agelas (SS-956), and the structure and relative stereochemistry were elucidated from spectroscopic data. Benzosceptrin C (1) showed antimicrobial activity.  相似文献   
997.
To analyze the relationship between biomass of microorganisms and methane production, the total biomass of bacteria and archaea (BA) during methane fermentation was analyzed by the environmental DNA analysis method. In the case of using methanogenic sludge as a seed which is generally used for methane fermentation, the total BA biomass reached to 1.5 × 108 to 3.6 × 108 cells/ml when methane was produced. On the other hand, soil suspension was used as a seed; methane was not produced for 14-day cultivation. However, the total BA biomass reached to above 1.5 × 108 cells/ml. The methanogen biomass was counted by using a fluorescence microscope (coenzyme F420), and the methanogen biomass and the ratio of methanogens in the total of BA were analyzed during methane fermentation. At the methane-producing phase, the methanogen biomass reached to 1.3 × 108 cells/ml, and the ratio of methanogens was above 70% of the total BA. When the ratio of methanogens in a seed was changed, the methane-producing phase was moved. However, the relationship between methanogens and other microorganisms at the methane-producing phase was almost similar.  相似文献   
998.
Bridging the gap : Snapshots of 1,6‐H‐shift precursors indicate that a narrower C? H???C+ separation (D in the ORTEP diagram) in the title complexes induces faster degenerate rearrangement of 1 +. A contact distance of less than 2.7 Å is necessary to realize the organic three‐center two‐electron bond of [C? H? C]+, as indicated by extrapolation of the X‐ray data.

  相似文献   

999.
A series of chiral amino alcohols transformed into the formamidine derivative of 1, 2, 3, 4-tetrahydroisoquinolines were evaluated as chiral dipole-stabilized anions. Alkylation with alkyl halides provided the 1-alkyl-l, 2, 3, 4-tetrahydroisoquinolines in both excellent yield and enantiomeric purity.  相似文献   
1000.
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