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101.
Direct meso-alkynylation of β,β'-dipyridylporphyrin with various alkynyllithium reagents has been achieved, in which the β,β'-dipyridyl groups play an important role in facilitating the nucleophilic addition of the reagents through double coordination. This method enabled the synthesis of a meso-ethynylene-bridged diporphyrin. 相似文献
102.
XINMei-hua WANGMin LIMing-chun LIUChao SUNDuo-xia MITSUISHIMasaya MIYASHITATokuji 《高等学校化学研究》2004,20(2):210-212
With sodium dodecyl sulfonate(SDS) as the phase transferring catalyst, N,N-Dilauryl chitosans with a high degree of alkyl group substitution were prepared and characterized by means of FTIR, ^1H NMR and elemental analyses. The results indicate that the average degree of alkyl group substitution on the chitosan increases with decreasing the molecular weight of the chitosan. The fully N,N-dilaurylated chitosan was found to be dissolvable in chloroform. The collapsed pressures of the samples derived from chitosan with 3000,5000 and 10000 dalton are 47.6, 48. 2 and 51.0 mN/m, respectively. The surface area occupied by the monomer unit(glucosamine) of all. those samples is 0:6 nm^2. 相似文献
103.
Adare A Afanasiev S Aidala C Ajitanand NN Akiba Y Al-Bataineh H Alexander J Aoki K Aphecetche L Armendariz R Aronson SH Asai J Atomssa ET Averbeck R Awes TC Azmoun B Babintsev V Bai M Baksay G Baksay L Baldisseri A Barish KN Barnes PD Bassalleck B Basye AT Bathe S Batsouli S Baublis V Baumann C Bazilevsky A Belikov S Bennett R Berdnikov A Berdnikov Y Bickley AA Boissevain JG Borel H Boyle K Brooks ML Buesching H Bumazhnov V Bunce G Butsyk S Camacho CM Campbell S Chang BS Chang WC Charvet JL 《Physical review letters》2008,101(16):162301
Neutral pion transverse momentum (p(T)) spectra at midrapidity (|y| less than or approximately 0.35) were measured in Cu+Cu collisions at sqrt[s(NN)]=22.4, 62.4, and 200 GeV. Relative to pi_(0) yields in p+p collisions scaled by the number of inelastic nucleon-nucleon collisions (N(coll) the pi_(0) yields for p(T) more than or approximately 2 GeV/c in central Cu+Cu collisions are suppressed at 62.4 and 200 GeV whereas an enhancement is observed at 22.4 GeV. A comparison with a jet-quenching model suggests that final state parton energy loss dominates in central Cu+Cu collisions at 62.4 and 200 GeV, while the enhancement at 22.4 GeV is consistent with nuclear modifications in the initial state alone. 相似文献
104.
Afanasiev S Aidala C Ajitanand NN Akiba Y Alexander J Al-Jamel A Aoki K Aphecetche L Armendariz R Aronson SH Averbeck R Awes TC Azmoun B Babintsev V Baldisseri A Barish KN Barnes PD Bassalleck B Bathe S Batsouli S Baublis V Bauer F Bazilevsky A Belikov S Bennett R Berdnikov Y Bjorndal MT Boissevain JG Borel H Boyle K Brooks ML Brown DS Bucher D Buesching H Bumazhnov V Bunce G Burward-Hoy JM Butsyk S Campbell S Chai JS Chernichenko S Chiba J Chi CY Chiu M Choi IJ Chujo T Cianciolo V Cleven CR 《Physical review letters》2008,101(8):082301
Measurements in Au+Au collisions at sqrt[s_{NN}]=200 GeV of jet correlations for a trigger hadron at intermediate transverse momentum (p_{T,trig}) with associated mesons or baryons at lower p_{T,assoc} indicate strong modification of the away-side jet. The ratio of jet-associated baryons to mesons increases with centrality and p_{T,assoc}. For the most central collisions, the ratio is similar to that for inclusive measurements. This trend is incompatible with in-vacuum fragmentation but could be due to jetlike contributions from correlated soft partons, which recombine upon hadronization. 相似文献
105.
Kin-ya Akiba Akiyoshi Shimizu Hideyuki Ohnari Katsuo Ohkata 《Tetrahedron letters》1985,26(27):3211-3214
Tributylstibine is an efficient reagent for debromination of phenacyl and arylmethyl bromides. The mechanistic difference between stibine and phosphine is discussed briefly. 相似文献
106.
Takefumi Yano Tokuji Inoue Shigeru Ikai Michimasa Shimizu Yoshiyuki Kai Masanori Tamura 《Journal of polymer science. Part A, Polymer chemistry》1988,26(2):457-464
Supports were obtained by the interaction of C4H9MgCl with the reaction mixture of AlCl3 and CH3Si(OC2H5)3 or Si(OC2H5)4 (Mg/Al/Si = 2/1/1). With the combination of Al(C2H5)3 and methyl-p-toluate, immobilized titanium catalysts prepared by the treatment of the supports with TiCl4 and ethylbenzoate showed extraordinary high activity and stereoregularity in the polymerization of propylene.1 By the study of the reaction of AlCl3 with CH3Si(OC2H5)3, the elemental analysis and powder x-ray diffractometric measurements of the supports, it was found that the supports comprised of Cl, Mg, Al, and Si atoms, OC2H5 groups, C4H9 groups, and ethers, and that they were amorphous solids to the extent that the x-ray diffraction peak assigned to the 003 plane in MgCl2 crystals completely disappeared. 相似文献
107.
We study the3 P 0 quark-antiquark pair condensation in QCD, representing the gluon-interaction approximately by instantaneous Coulomb plus Breit potential. Particular attention is paid to non-uniqueness of the solution of the gap equation. The genuine dynamical solution can be characterized by a rapidly convergent behavior at large momentum, as was recognized in covariant formulations of Landau gauge. We impose the required behavior and make a numerical study of the chiral condensation. 相似文献
108.
LI Tie-sheng Masaya Mitsuishi Tokuji Miyashta 《高等学校化学研究》2006,22(4):543-546
IntroductionDeep-UV lithography is generally recognized asthe most promising lithographic technology, for the pro-duction of high-resolution devices. However, lithogra-phy requires high sensitivity, high resolution, and highresistance. To make this techno… 相似文献
109.
Kin-ya Akiba Yoshio Negishi Katsuyuki Kurumaya Noboru Ueyama Naoki Inamoto 《Tetrahedron letters》1981,22(49):4977-4980
Dimethyl 2-isopropoxycarbonyl-1, 2-dihydroisoquinoline-1-phosphonate () was prepared from isoquinoline, isopropyl chloroformate, and trimethyl phosphite. Wittig-Horner reaction of with various aldehydes afforded the corresponding exo-methylene compounds, which were converted to 1-substituted isoquinolines with hydrogen chloride. 相似文献
110.
S. Nakamura M. Takeyasu K. Akiba 《Journal of Radioanalytical and Nuclear Chemistry》1994,181(2):281-289
Transport of La, Nd, Eu, Tb, Tm and Lu through a supported liquid membrane (SLM) was investigated by using di(2,4,4-trimethylpentyl)phosphinic acid (DTMPPA) as a mobile carrier. Lanthanoid elements in the feed solution were quantitatively transported and concentrated into the product solution of mild acidity. The transport rates increased with increasing atomic number of lanthanoids in the low pH region of the feed solution. Separation factors evaluated from the transport rates for lanthanoids were close to those from the distribution ratios in liquid-liquid extraction. 相似文献