A chromenoquinoline-based fluorescent off-on thiol probe for bioimaging

A new chromenoquinoline-based fluorescent off-on thiol probe 2 is reported. In aqueous buffer solutions at physiological pH, the probe exhibited 223-fold enhancement in fluorescence intensity by a Michael addition of cysteine to the maleimide appended to a chromenoquinoline. Cell permeability and live cell imaging of thiols are also demonstrated.     

Matrix factorization method for the Hamiltonian structure of integrable systems

We demonstrate that the process of matrix factorization provides a systematic mathematical method to investigate the Hamiltonian structure of non-linear evolution equations characterized by hereditary operators with Nijenhuis property.     

Geometric phase from a combined evolution‐operator‐invariant technique

The quantum phase problem is investigated by a synthesis of the evolution operator technique and method of invariants. This approach has been found to be quite effective to disclose interrelationship between geometric phases differing in the nature of evolution and to obtain results for them without invoking the concept of parallel transport in the projective Hilbert space. The usefulness of the method developed is ascertained by studying the geometric phases associated with spinor evolutions in rotating magnetic field. This revised version was published online in July 2006 with corrections to the Cover Date.     

Isolation and structure determination of two new macrocyclic biaryl ethers fromGaruga gamblei

Two new macrocyclic biaryl ethers have been isolated from the bark ofGaruga gamblei King (Burseraceae). The structure of the compounds has been established by NMR spectroscopy.

---

Isolierung und Strukturermittlung von zwei neuen makrocyclischen Biarylethern aus Garuga gamblei (Kurze Mitteilung)

Zusammenfassung Aus der Rinde vonGaruga gamblei King (Burseraceae) wurden zwei neue makrocyclische Biarylether isoliert. Die Struktur der Verbindungen wurde mittels NMR-Spektroskopie bestimmt.

     

Two colour multiphoton ionization spectroscopy of uranium from a metastable state

Using two pulsed tunable dye lasers, a two colour multiphoton ionization process has been utilised to explore the higher energy levels of uranium. One hundred and thirty eight new UI levels have been observed in the 37540–38420 cm^–1 region. J assignments of these levels have been suggested on the basis of their excitation from intermediate levels with known and contiguous J values. In eight cases the J assignments are unique.     

Removal of Cu(II) and Pb(II) from Aqueous Solutions Using Nanoporous Materials

Russian Journal of Physical Chemistry A - The present work deals with the adsorption of Cu2+ and Pb2+ on zeolites (ZSM-5, mordenite) and mesoporous materials (MCM-48, MCM-41). The characterization...     

Highly dispersed Mn2O3−Co3O4 nanostructures on carbon matrix as heterogeneous Fenton-like catalyst

This work reports the synthesis of various carbon (Vulcan XC-72 R) supported metal oxide nanostructures, such as Mn₂O₃, Co₃O₄ and Mn₂O₃−Co₃O₄ as heterogeneous Fenton-like catalysts for the degradation of organic dye pollutants, namely Rhodamine B (RB) and Congo Red (CR) in wastewater. The activity results showed that the bimetallic Mn₂O₃−Co₃O₄/C catalyst exhibits much higher activity than the monometallic Mn₂O₃/C and Co₃O₄/C catalysts for the degradation of both RB and CR pollutants, due to the synergistic properties induced by the Mn−Co and/or Mn (Co)−support interactions. The degradation efficiency of RB and CR was considerably increased with an increase of reaction temperature from 25 to 45°C. Importantly, the bimetallic Mn₂O₃−Co₃O₄/C catalyst could maintain its catalytic activity up to five successive cycles, revealing its catalytic durability for wastewater purification. The structure–activity correlations demonstrated a probable mechanism for the degradation of organic dye pollutants in wastewater, involving •OH radical as well as Mn²⁺/Mn³⁺ or Co²⁺/Co³⁺ redox couple of the Mn₂O₃−Co₃O₄/C catalyst.     

System size effect on the critical behavior in nuclear multifragmentation

Attempt has been made to examine the role of system size on the traditional signatures of critical behavior from a comparative study of Mg-Em at 4.5 A GeV and Kr-Em at 0.95 A GeV interactions. A number of relevant observables such as fluctuation in the sizes of the largest cluster, reduced variance and the mean value of second moment of charge distribution were estimated with the experimental data. From a comparison of our results with that of EOS collaboration for Au, La and Kr on carbon at 1 A GeV, a definite systematic variation in the heights and positions of the peaks could be observed with the change of fragmenting nuclei thereby confirming the effect of system size on MF mechanism.     

Conduction–radiation interaction in 3D irregular enclosures using the finite volume method

Interaction of conduction and radiation in 3D enclosures is carried out with a gray participating media. Application of block structured grid is shown with the finite volume method (FVM). Radiation modeling is performed with the FVM and is coupled with an ‘in-house’ code to solve the set of transport equations. The detailed numerical results are presented for a cubical and a cylindrical enclosure as these results are not available in the literature. The numerical simulation for the cylindrical enclosure is performed using a block-structured ‘O’ grid. Two additional geometries are considered in order to show the applicability of the present work. Results of temperature, radiative heat flux and total heat flux distributions are presented for different optical thicknesses, scattering albedoes, emissivities and conduction–radiation parameters. The 3D results are validated with the available 2D results or results with pure radiation problems as limiting cases.