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111.
Honda K Akamatsu D Arikawa M Yokoi Y Akiba K Nagatsuka S Tanimura T Furusawa A Kozuma M 《Physical review letters》2008,100(9):093601
Storage and retrieval of a squeezed vacuum was successfully demonstrated using electromagnetically induced transparency. The squeezed vacuum pulse having a temporal width of 930 ns was incident on the laser cooled 87Rb atoms with an intense control light in a coherent state. When the squeezed vacuum pulse was slowed and spatially compressed in the cold atoms, the control light was switched off. After 3 mus of storage, the control light was switched on again, and the squeezed vacuum was retrieved, as was confirmed using the time-domain homodyne method. 相似文献
112.
Nan Zhang Dr. Tohru Kawamoto Yong Jiang Dr. Akira Takahashi Dr. Manabu Ishizaki Miyuki Asai Prof. Masato Kurihara Prof. Zhenya Zhang Dr. Zhongfang Lei Dr. Durga Parajuli 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(23):5950-5958
Cobalt hexacyanoferrate of various compositions was prepared in flow mode and the role of the vacancy on the structure, thermogravimetric (TG) properties, and the adsorption efficiency was studied. The material, NayCo[Fe(CN)6]1−x ⋅ z H2O, with a minimum vacancy of x=0.014 to the highest x=0.47, was obtained. The TG-differential scanning calorimetry (DSC) profile showed a distinct influence of the vacancy on the water release temperature. Materials with x>0.35 showed a smooth release of water at a relatively lower temperature. However, for the materials with x<0.35, water release took place in multiple steps, suggesting the existence of various forms of water. The FTIR profiles supported the existence of free and bonded water molecules. However, the materials with multiple water peaks in the FTIR spectra showed a shift of the major XRD peaks when heated at 285 °C in N2 atmosphere. Regarding the effect of the vacancy on the adsorption behavior, for NH4, the adsorption was found to be proportional to the number of Na atoms in the material, confirming the ion-exchange process. On the contrary, the materials with low vacancy and high Na content showed nominal Cs adsorption capacity. Interestingly, the K adsorption capacity was found to be in between that of the other two ions. This means the ionic size decides the rate of placement into the interstitial sites. For larger ions like Cs, the ease of percolation via the vacancy decides the overall adsorption efficiency. 相似文献
113.
Xiaopei Li Tasuku Ogihara Prof. Dr. Manabu Abe Dr. Yasuyuki Nakamura Prof. Dr. Shigeru Yamago 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(42):9846-9850
The effect of viscosity on the diffusion efficiency (Fdif) of an organic radical pair in a solvent cage and the termination mechanism, that is, the selectivity of disproportionation (Disp) and combination (Comb) of the geminated caged radical pair and the diffused radicals encountered, were investigated quantitatively by following the photolysis of dimethyl 2,2′-azobis(2-methylpropionate) (V-601) in the absence and presence of PhSD. Fdif and Disp/Comb selectivity outside the cage [Disp(dif)/Comb(dif)] are highly sensitive to the viscosity. In contrast, the Disp/Comb selectivity inside the cage [Disp(cage)/Comb(cage)] is rather insensitive. The difference in viscosity dependence between Disp(cage)/Comb(cage) and Disp(dif)/Comb(dif) is explained by the spin state of the radical pair inside and outside the cage and the spin state dependent configurational changes of the radical pair upon their collision. Given that the configurational change of the radicals associates the displacement and reorganization of solvents around the radicals, the termination outside the cage, which requires larger change than that inside the cage, is highly viscosity dependent. Furthermore, while the bulk viscosity of each solvent shows good correlation with Fdif and Disp/Comb selectivity, microviscosity is the better parameter predicting Fdif and Disp(dif)/Comb(dif) selectivity regardless of the solvents. 相似文献
114.
Inside Cover: A Puckered Singlet Cyclopentane‐1,3‐diyl: Detection of the Third Isomer in Homolysis (Chem. Eur. J. 7/2016)
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Second generation polyphenol dendrimers (PDs) with different core molecules were synthesized, and their chemiluminescence (CL) was measured by reacting the PDs with H2O2 under alkaline conditions. All of the PDs showed a strong CL, more than 120-fold greater than that of gallic acid. Various CL intensities of the PDs were obtained using different core molecules in the PDs. The distance between each dendron in the PD structure is crucial in the PD CL intensity. 相似文献
118.
Node M Hashimoto D Katoh T Ochi S Ozeki M Watanabe T Kajimoto T 《Organic letters》2008,10(13):2653-2656
The Michael addition of a chiral amine [(-)- 6] to alpha,beta-unsaturated esters ( 4) was attained and the stereoselectivity was inverted by changing the solvent from diethyl ether to tetrahydrofuran when alpha,beta-unsaturated esters having an aromatic ring at the beta-position were employed. In addition, the chiral auxiliary in the Michael adducts ( 9A) was facilely removed with N-iodosuccinimide to afford beta-amino esters ( 10A) and 2-methoxy- d-bornylaldehyde ( 11), which can be reclaimed to the chiral amine ( 6) by reductive amination. 相似文献
119.
A highly enantioselective organozinc (R2Zn) addition to a series of aldehydes and ketones was developed based on conjugate Lewis acid–Lewis base catalysis. Optically active secondary and tertiary alcohols were obtained in high yields with high enantioselectivities without Ti(IV) compounds. Bifunctional chiral 3,3′‐diphosphoryl‐BINOL ligands were designed and prepared through a phospho‐Fries rearrangement as a key step. On the other hand, bifunctional chiral phosphoramide ligands were designed and prepared from L ‐valine. Mechanistic studies were performed by X‐ray analyses of Zn(II) cluster and chiral ligands, a 31P NMR experiment on Zn(II) complexes, and stoichiometric reactions with some chiral or achiral Zn(II) complexes to propose a transition state assembly that includes monomeric active intermediates. © 2008 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 8: 143–155; 2008: Published online in Wiley InterScience ( www.interscience.wiley.com ) DOI 10.1002/tcr.20146 相似文献
120.
Daisuke Onoshima Noritada Kaji Manabu Tokeshi Yoshinobu Baba 《Analytical sciences》2008,24(2):181-183
We have developed a fluorescence resonance energy transfer (FRET) probe based on the conjugation of a quantum dot (QD) with dye (YOYO-3) intercalated DNA. The FRET-inducing electrostatic coupling of DNA and the QD made structural changes to the QD-DNA conjugates, which significantly prevented an enzymatic reaction between the DNA and a conventional restriction endonuclease (EcoRI). 相似文献