1,688 research outputs found
Pb(II) and Mn(II) Supermolecular Polymers of Bipy and (4-Chlorophenyloxy) Acetate Anions: Syntheses, Structure and Fluorescence Properties
Two new supermolecular polymers of the formula [Pb4L8(2,2’-bipy)4] 1 and [MnL2(4,4’-bipy)] 2 [HL = (4-chlorophenyloxy)acetic acid] have been synthesized and characterized by X-ray single crystal diffraction analysis, elemental analysis, fluorescence spectroscopy method and electrochemical analysis. Complex 1 is a multinuclear dimmer in which four Pb ions are linked together by the L ligands. In complex 2, each carboxyl of L bridges two Mn ions to form infinite Mn–O–C-Orods. Both in complex 1 and complex 2, π–π stacking and van der Waals’ interactions make the two complexes stable, 3-D, supermolecular polymers. This work will contribute to the design and synthesis of fluorescent, supramolecular polymers.Keywords: Supermolecular polymers, fluorescence, 4-chlorophenyloxyacetic aci
Determination of Chemical Constituents of the Marine Pulmonate Slug, Paraoncidium reevesii
Purpose: To isolate and identify the chemical components of Paraoncidium reevesii.Methods: Silica gel column chromatography was used to isolate the components from petroleum ether and ethyl acetate fractions of the acetone extract, and the structures of the compounds were derived from 1H-nuclear magnetic resonance (1H-NMR), 13C-nuclear magnetic resonance (13C-NMR) and mass spectrometry (MS) analyses and also with the aid of literature data for authenticated samples.Results: Cholesterol (1), baconipyrone D (2), chimyl alcohol (3), batyl alcohol (4), á-monpalmitin (5), stearic acid (6), 3-indolecarboxylic acid (7), uracil (8), thymine (9), uridine (10), thymidine (11) were isolated from the marine slug (Paraoncidium reevesii).Conclusion: All the isolated compounds are being reported here for Paraoncidium reevesii for the first time. The results provide base data for further study of the Onchidiidae as a Chinese traditional remedy for asthma and athlete’s foot.Keywords: Mollusk, Paraoncidium reevesii, Baconipyrone D, Batyl alcohol, Chimyl alcohol Onchidiidae, Marine Pulmonate, Slug, Asthma, Athlete’s foo
Protective antitumor activity induced by a fusion vaccine with murine beta-defensin2 and VE-cadherin in mouse models
Targeting angiogenesis is an effective strategy for anticancer therapy. The vascular endothelialcadherin (VE-cad) regulated angiogenesis is a potential target for anti-angiogenesis. Here, we develop a fusion vaccine plasmid DNA pSec-MBD2-VE-cad from VE-cad and murine beta defensin2 (MBD2) to induce immunity for cancer therapy. The expression and biological activity of fusion protein were detected in vitro. Anti-tumor effects and inhibition of angiogenesis via pSec-MBD2-VE-cad were investigated in mice model. The anti-VE-cad antibodies and cytotoxic T lymphocyte (CTL) responses were analyzed. Inhibition of tumor-induced angiogenesis and prolonged survival were shown in mice challenged with murine colon adenocarcinoma (CT26) or Murine fibrosarcoma cell line (MethA) after immunization with the fusion vaccine. Moreover, VE-cad-specific antibodies and specific T cell cytotoxicity were detected. The fusion vaccine based on self immune peptide Murine beta defensin2 (MBD2) and self antigen mVE-cad could induce autoimmunity and inhibit tumor growth, and thus there may be potential applications in cancer therapy
Dipole-Quadrupole Theory of Surface Enhanced Infrared Absorption and Appearance of Forbidden Lines in the SEIRA Spectra of Symmetrical Molecules
The paper presents main aspects of the Dipole-Quadrupole theory of Surface
Enhanced Infrared Absorption (SEIRA). It is pointed out the possibility of
appearance of the lines, caused by totally symmetric vibrations transforming
after the unit irreducible representation, which are forbidden in usual
infrared absorption spectra in molecules with sufficiently high symmetry.
Observation of such lines in the SEIRA spectra of diprotonated and ethylene,
adsorbed on and on mordenites is pointed out. The results well agree with our
ideas about surface enhanced optical processes, based on the conception of a
strong quadrupole light-molecule interaction, which allows us to develop the
SERS and SEHRS theories.Comment: 15 pages,3 figures, 1 tabl
Measurements of branching fractions for inclusive K0~/K0 and K*(892)+- decays of neutral and charged D mesons
Using the data sample of about 33 pb-1 collected at and around 3.773 GeV with
the BES-II detector at the BEPC collider, we have studied inclusive K0~/K0 and
K*(892)+- decays of D0 and D+ mesons. The branching fractions for the inclusive
K0~/K0 and K*(892)- decays are measured to be BF(D0 to K0~/K0
X)=(47.6+-4.8+-3.0)%, BF(D+ to K0~/K0 X)=(60.5+-5.5+-3.3)%, BF(D0 to K*-
X)=(15.3+- 8.3+- 1.9)% and BF(D+ to K*- X)=(5.7+- 5.2+- 0.7)%. The upper limits
of the branching fractions for the inclusive K*(892)+ decays are set to be
BF(D0 to K*+ X)<3.6% and BF(D+ to K*+ X) <20.3% at 90% confidence level
Direct Measurements of the Branching Fractions for Inclusive and Inclusive Semileptonic Decays of and Mesons
With singly-tagged samples selected from the data collected at and
around 3.773 GeV with the BESII detector at the BEPC collider, we have measured
the branching fractions for the inclusive decays of and
mesons, which are , , and
, respectively. We have also
measured the branching fractions for the inclusive semileptonic decays of
and mesons to be and . These yield the ratio of their partial
widths to be .Comment: 6 pages, 5 figure
Measurement of \psip Radiative Decays
Using 14 million psi(2S) events accumulated at the BESII detector, we report
first measurements of branching fractions or upper limits for psi(2S) decays
into gamma ppbar, gamma 2(pi^+pi^-), gamma K_s K^-pi^++c.c., gamma K^+ K^-
pi^+pi^-, gamma K^{*0} K^- pi^+ +c.c., gamma K^{*0}\bar K^{*0}, gamma pi^+pi^-
p pbar, gamma 2(K^+K^-), gamma 3(pi^+pi^-), and gamma 2(pi^+pi^-)K^+K^- with
the invariant mass of hadrons below 2.9GeV/c^2. We also report branching
fractions of psi(2S) decays into 2(pi^+pi^-) pi^0, omega pi^+pi^-, omega
f_2(1270), b_1^\pm pi^\mp, and pi^0 2(pi^+pi^-) K^+K^-.Comment: 5 pages, 4 figure
Measurements of and decays into and
Using 58 million and 14 million events collected by the
BESII detector at the BEPC, branching fractions or upper limits for the decays
and and are measured. For the isospin violating decays, the upper
limits are determined to be and at the 90% confidence level. The isospin
conserving process is observed for the
first time, and its branching fraction is measured to be , where the
first error is statistical and the second one is systematic. No signal is observed in decays, and is set at the 90%
confidence level. Branching fractions of decays into and are also reported, and the sum
of these branching fractions is determined to be .Comment: 7 pages, 10 figures. Phys.Rev.D comments considere
First observation of
Using 14 million events collected with the Beijing Spectrometer
(BESII) at the Beijing Electron-Positron Collider, the branching fractions of
decays to and and the branching
fractions of the main background channels ,
, , and are determined. The contributions of the
resonances in are also
discussed.Comment: 19 pages, 8 figures, add vertex requirement systematic erro
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