bluuebunny/crossref_metadata_2025 huggingface dataset:
Theoretical studies on silathione and its unimolecular reactions
Authors: Han Yun‐Zhu , Zhao Cheng‐Da
Published: April 2011

The unimolecular reactions of silathione: (a) dehydrogenation, (b) trans‐isomerization, (c) cis‐isomerization, are investigated by ab initio MO calculations using RHF/4‐31G basis set. The geometries and energies of the reactant, transition states and products have been determined on the singlet potential energy surface of the ground state. The reaction ergodography along the intrinsic reaction coordinate (IRC) for the three reactions has also been performed.
Reaction ergodography for the 1,2‐H shift and inversion processes of amino‐carbene
Authors: Chen Bin , Zhao Cheng‐Da , Fu Qiang
Published: April 2011

The ab initio calculations have been performed on the reaction paths of 1,2‐H shift and inversion processes of amino‐carbene molecule by the Intrinsic Reaction Coordinate (IRC) method. We have determined the equilibrium geometries and energies of the reactant, transition state and product, and obtained the activation energies, reaction heats, frequency factors and the activation entropies of these two reaction processes. The vibrational correlation from reactant to transition state indicated that the IRCs of 1,2‐H shift and inversion processes were associated with the deformation modes of 1540 and 1208 cm−1, respectively. The vibrational coupling between normal coordinates in the inversion process would be helpful for selecting the inversion reaction channel.
The essential aspect and regular pattern of ion transfer across the liquid‐liquid interface
Authors: Wang Er‐Kang , Sun Zhi‐Sheng
Published: April 2011

Three empirical rules of interfacial potential and Gibb's energy with the radius, charge number of transfer ions and dielectric constant of organic phase are obtained for the ion transfer across the liquid‐liquid interface, which are verified by the transfer of simple anions, dye ions and metal ions facilitated by neutral ionophores across the interface between water and some organic solvents, and deduced theoretically based on the electrostatic interaction of ion and high‐permittivity solvent. The rules are proved to be effective of choosing supporting electrolytes and searching for new transfer system which follows the rule that r/n of transfer ion should be larger than that of electrolytes ion in water phase and less than that in organic phase. A rule for judgement of the charge sign of transfer ion is suggested firstly based on the relationship between interfacial half‐wave potential and dielectric constant of organic phase.
An investigation of chemically deposited Ni‐P alloys by EXAFS and XRD
Authors: Ma Li‐Dun , Lü Gang , Shen Xiao‐Liang
Published: April 2011

Five samples of chemically desposited Ni‐P amorphous alloys were prepared and investigated. In these amorphous alloys there are Ni‐P atom groups in which phosphorus and nickel are connected with strong interaction. Nickel atoms and Ni‐P groups are deposited in a random manner on the surface of matrix and a quasilayer structure is formed. The spacing between two layers in alloys resembles that in (111) plane in the nickel crystal. Therefore there is a peak at the same position of 2θ=44.4° as that of the (111) reflection of crystalline nickel in the X‐ray powder diffraction pattern of alloys. However, the dimension of Ni‐P groups is different from that of a nickel atom and the atomic arrangement in the layer is in disorder. These result in the space change and there is a distribution of spacing around the average. As a consequence of distribution of spacings, the peak at 2θ=44.4° is broadened and enhanced as the amount of P increases.
Assignment of the non‐exchangeable proton resonances and conformational analysis of oligonucleotide DNA d(TTGGGGTT) by two‐dimensional nuclear magnetic resonance methods;
Authors: Dong Yan‐Hong , Tang Wen‐Xia , Dai An‐Bang , Wu Jia‐Zhen , Boom J. H. , Reedijk J. , Struik A. F.
Published: April 2011

Two‐dimensional NMR study on the single‐stranded octadeoxynucleotide, d(TT‐GGGGTT) is presented. Assignments of the base protons, the H1′, H2′ and H2″ protons were made by two‐dimensional Nuclear Overhauser Enhancement Spectroscopy (NOESY) and two‐dimensional homonuclear J‐correlated Spectroscopy (COSY). The result indicates that the overall structure of the single‐stranded d (TTGGGGTT) is a right‐handed B‐type helix.
Studies on the primary structure of chicken apolipoprotein A‐I using HPLC technique
Authors: Gu Zi‐Wei , Weng Shi‐Ai , Kim T. W. , Yang Chao‐Yuh
Published: April 2011

The complete amino acid sequence of chicken plasma apolipoprotein (apo) A‐I was determined by sequencing overlapping peptide fragments produced by trypsin, S. aureus V8 protease, and cyanogen bromide cleavage respectively. All of the peptide fragments were purified on a Waters or on a Beckman HPLC system with a Vydac C18 column using 0.1% TFA in water as buffer A, and 0.08% TFA in 95% acetonitrile and 5% water as buffer B. Most of the peaks separated by these systems were pure. The partially purified fractions were subjected to rechromatography with a Hypersil ODS column using 0.005M sodium phosphate, pH 6.0, as buffer A, and 90% acetonitrile and 10% water as buffer B. The N‐terminus of chicken apo A‐I was determined to be aspartic acid by directly sequencing the intact protein up to 30 residues, while the C‐terminus was identified as alanine by carboxypeptidase Y cleavage. There are 240 amino acid residues in mature chicken apo A‐I. By direct analysis of cyanogen bromide peptide, we also determined the sequence of a 6 amino acid prosegment, which is present at approximately 10% of the molar amount of the mature protein in chicken plasma.
Studies on the reaction of cupric(II) perfluoroalkanesulfinate
Authors: Huang Wei‐Yuan , Xie Yuan
Published: April 2011

Reaction of aqueous solution of sodium perfluoroalkanesulfinate with cupric sulphate gave a high yield of cupric perfluoroalkanesulfinate, which decomposed slowly in the air on exposure to light to give perfluorocarboxylic acid. The reaction between cupric perfluoroalkanesulfinate and olefins in the presence of potassium iodide and excess CuSO4 in ether at low temperature (‐30 to‐20°C) formed two kinds of adducts, namely the normal adducts, Rf SO2CH2CHIR(2) and the adducts resulting from the loss of SO2 moiety, Rf CH2CHIR(3) in yields ranging from morderate to good. These results were identical with that of the addition of perfluoroalkanesulfonyl iodide to olefins. A radical reaction mechanism is proposed.
The Wittig sigmatropic rearrangement in a conjugated diene system I
Authors: Li Zheng‐Ming , Wang Tian‐Sheng , Yao En‐Yun , Gao Zheng‐Heng
Published: April 2011

A conjugated dienic benzyl ether was shown to undergo Wittig sigmatropic rearrangement to give a mixture of [1,2] and [1,4] besides the expected [2,3] rearrangement product. The solvent effect as well as the reaction pathways were discussed.
The crystal structure of a new gossypol derivative: — 8,8′‐Dibromo‐6,6′,7,7′‐tetramethoxy‐5,5′‐diisopropyl‐3,3′‐ oxydimethylene dinaphtho[2,1‐b:2′,1′‐d]furan
Authors: Gui‐Dong Zhu , De‐Hua Chen , Jian‐Hua Huang , Ching‐Sung Chi , Jun Dong , Min‐Qin Chen , Pei‐Ju Zheng
Published: April 2011

8,8′‐Dibromo‐6,6′, 7,7′‐tetramethoxy‐5,5′‐diisopropyl‐3,3′‐oxydimethylene dinaphtho[2,1‐b:2′, 1′‐dlfuran, C32H30Br2*; M.W. = 670; triclinic; space group P1; a = 8.896(2), b = 10.216(1), c = 10.423(1)Å, a = 108.48(1), β = 119.36(1); γ = 99.26(1); V = 723.5 Å3; Z = 1, Dcal. = 1.479 g.cm−3. Mo Kα = 28.11 cm−1, F(000) = 326, T = 293 K. The structure was solved by direct method and full‐matrix least‐squares refinement converged at R = 0.034 for 2377 observed reflections. The oxygen atom in seven‐membered ring exists in a disordered arrangement. Both bisnaphthalene and oxygen‐containing five‐membered ring have planar conformations with dihedral angle 6*, showing marked aromatic feature.
XPS study of tungsten carbide
Authors: Dai‐Yi Qin , Zi Gao
Published: April 2011

The surface composition and electronic structure of tungsten carbides prepared by direct synthesis and carburization of white tungstic acid were studied with X‐ray photoelectron spectroscopy. The experimental results show that WO3 and free carbon are present on the surface of the carbides. For the high surface area tungsten carbide prepared from white tungstic acid a large extent of oxygen insertion into the crystal lattice was observed. Measurements of the binding energies of the W4f7 2, C1S and O18 core levels indicate that charge transfer is from the W to the C and O atoms, forming W5d‐C3p and W5d‐O2p bonding. The catalytic behavior of the tungsten carbides in hydrocarbon conversion reactions is mentioned and compared with Pt catalysts.
Infrared multiphoton dissociation of acetic anhydride: Experimental study
Authors: Tian‐Xiang Xiang
Published: April 2011

The infrared multi‐photon dissociation (IRMPD) of acetic anhydride to generate state‐selected CH2 has been investigated by using time and wavelength resolved fluorescence techniques. It has been observed that the generation of the nascent ground state CH2 (a1A1) is delayed by about 0.6 μ relative to the onset time of the excited CH2 (b1B1). The relative population of the ground and excited state CH2 and the onset time for the appearance of the ground state CH2 have been found to depend strongly on CO2 laser output fluences. These results appear to have a strong bearing on the structure of the potential energy surfaces of the intermediate CH2CO. A possible photolysis mechanism is proposed to explain these experimental results.
The determination of the crystal structure of tetrapotassium uranyl tricarbonate by powder X‐ray diffraction method
Authors: Jian‐Cheng Han , Suo‐Bao Rong , Qi‐Ming Chen , Xin‐Ran Wu
Published: April 2011

A uranyl compound, K4UO2(CO3)3 has been characterized by powder X‐ray diffraction method. M.W. = 606.46, monoclinic, C2/c (No. 15), a = 1.0240(7), b = 0.9198(4), c = 1.2222(12) nm, β = 95.12 (4)°, V = 1.1466(5) nm3, Z = 4, D = 3.468 g/cm3, Dc = 3.513 g/cm, λ(Cu Ka1) = 0.1540598nm, T = 298K. The structure was solved by heavy atom method and Fourier synthesis, and refined by full‐matrix least‐squares method to R = 0.1185 for 275 reflections. The uranium (VI) atom is in an eight‐coordinate distorted hexagonal‐bipyramidal environment with creasy fan shape. The linear uranyl group approaches to perpendicular to the equatorial plane in which three carbonate groups are chelated. U(VI) has two linear oxygen atoms closer to it (U]—0 = 0.1767 (5) nm) than six other neighbours (U—O ranging from 0.2516 to 0.2568 nm). The distances between carbon atoms and uncoordinated oxygen atoms are 0.122 (1) and 0.123(1) nm, which are distinctly different from those between carbon and coordinated oxygen atoms (mean 0.134(6) nm). This fact reveals the non‐equivalence of one oxygen atom to the other two in each carbonate. In K4UO2(CO3)3, the O—O distance for the adjacent carbonate groups is 0.2794(4)nm approaching to the sum of Van der Waals radii of two oxygen atoms. The K—O distances vary between 0.2667 and 0.3131 nm, and each anion is immediately surrounded by six potassium ions, only four of which can be considered to belong to the same structural formula unit, and they are symmetrically located above and below the equatorial plane.
Effects of heteroatoms on 1,2‐rearrangements of 3‐membered ring carbenes
Authors: Bing‐Ze Wang , Jin‐Ting Liu , Xiao‐Fang Li , Cong‐Hao Deng
Published: April 2011

1,2‐rearrangements of carbenes: CCH2X(X = CH2, NH and O) are studied by using ab initio gradient method. Heteroatoms N and O stabilize the carbene and decrease its reactivity, mainly by changing frontier molecular orbitals, but retain the way of the reaction. The reaction starts from the attack of the migrating hydrogen on the carbene p AO and ends with the entrance of the hydrogen into the carbene σ orbital. Reactivities are in the order of X = CH8>NH>0. The reaction is exothermic or endothermic according to whether the product is a 4n+2 or 4n π electron molecule.
DNMR study of the azacrown ether conformations in solution
Authors: Dong‐Hui Wu , Lian‐Fang Shen , Guo‐Pin Xue , Cheng‐Tai Wu
Published: April 2011

The NMR methods (including 1H NMR, 13C NMR, variable temperature method and the novel ID EXSY technique) were employed to study the conformation of azacrown ethers 1—5 in solution. There are two classes of conformation in which the azacrown ethers exist in solution according to their molecular structure. Two kinds of intramolecular motion of the azacrown ethers were observed, one is the vibration of the macrocyclic ring and the other is its inversion. The ether rings which contain oxygens are more flexible than that constructed by nitrogens in the present case because of the tetrahedron structure of the nitrogen atoms and the hindrance of the groups Ts connected to the nitrogens. Some thermodynamical parameters of the ring inversion process were obtained.
Tetrahydrofolate coenzyme models: I. Synthesis of 1‐methyl‐2‐phenyl‐3‐aryl imidazolinium iodide and benzylidyne (phenyl‐substituted one carbon unit) transfer reactions
Authors: Chi‐Zhong Xia , Pei‐Wen Zhou , Jing‐Fan Ding
Published: April 2011

Four 1, 2, 3‐trisubstituted imidazolinium iodides which were used as 5,10 ‐+CPh‐THF model (7—10) at formic acid oxidation level were synthesized. The benzylidyne group (phenyl‐substituted one carbon unit) transfer reactions from these compounds to Grignard reagent were investigated, and the reactions of these compounds with KBH4 and NaOH were also studied.
Microenvironmental control of photochemical reactions: II. Fluorescence quenching of naphthalene and 1,3‐di‐(α‐naphthyl)propane by RNA and bases in aqueous methanol
Authors: Xue‐Gong Lei , Rui‐Qiang Xie , You‐Cheng Liu
Published: April 2011

The fluorescence quenching of naphthalene (2) and 1,3‐di(α‐naphythyl)propane (1) by RNA and bases in methanol‐water (v:v = 1:1) binary solvents in the presence or absence of cyclodextrin (CD) has been investigated. The results show that both the monomer and excimer fluorescence of 1 can be quenched by these quenchers. The quenching and rates depend on the quencher and temperature. It is shown that there is a critical temperature (Tc) for each quencher. Below Tc, the excimer fluorescence spectra show vibrational structures and the Stern‐Volmer plots are straight lines (for uracil and cytosine); while above the Tc, the vibrational structures disappear and the Stern‐Volmer plots deviate from linearity and curve upward. The former is a static process; while the latter is a mixture of both static and dynamic processes. The addition of α‐CD has no effect on the fine structure; whereas β‐CD prevents the appearance of this structure efficiently. The quenching rates both for the monomer and excimer of 1 by bases except cytosine in the presence of β‐CD at ambient temperature are not changed; the quenching of fluorescence of 1 by RNA in the presence of β‐CD, however, is hindered. Time‐resolved fluorescence study shows that the excimer fine structures appear from the zero time. The intensity of fine structures depend on the fraction of water (π) in binary solvents, and it is independent of the pH value of the solvents. It is suggested that bases and RNA induced aggregates (perhaps microcrystal) are formed, in which the motion of molecules 1 is limited.
Studies on sulfinatodehalogenation: XVI. Sodium dithionite‐initiated addition of perfluoroalkyl iodides to terminal alkynes
Authors: Wei‐Yuan Huang , Long LÜ , Yuan‐Fa Zhang
Published: April 2011

Reaction of perfluoroalkyl iodides with a series of alkynes under sulfinatodehalogenation condition gave a mixture of E/Z adducts very readily in high yield, thus constituted a mild, convenient and effective new method for the addition of perfluoroalkyl iodides to alkynes. Under the same condition, in the presence of 1‐hexyne perfluoroalkyl bromide and 1,1,1‐trichlorotrifluoroethane reacted only to give sulfinates as the major products. A radical mechanism was proposed for the addition reaction.
Rongalite‐initiated addition of perfluoroalkyl iodides to olefins
Authors: Bing‐Nan Huang , Jin‐Tao Liu
Published: April 2011

Perfluoroalkyl iodides reacted with olefins in aqueous acetonitrile in the presence of Rongalite‐sodium bicarbonate under mild conditions to give the corresponding 1:1 adducts in moderate to high yields. The formation of these products and the orientation of the addition seemed to show that radicals took part in the reaction. This provides a convenient method for perfluoroalkylation.
Aggregation of l,3‐di(α‐naphthyl)propane and di(α‐naphthylmethyl)ether in aqueous binary solvents
Authors: Xue‐Gong Lei , You‐Cheng Liu
Published: April 2011

The UV absorption and fluorescence spectra of 1,3‐di (α‐naphthyl) propane (1), di (α‐naphthylmethyl) ether (2), and α‐methylnaphthalene (3) in aqueous methanol, ethanol, and DMSO were recorded as a function of π value (fraction of water in binary solvents). The existence of two states, a metastable state (defined as m) and a stable stationary state (defined as s), of molecules 1 as well as 2 in the above cosolvents at high π was shown by the contrary fluorescence excimer to monomer intensity (Ie/Im) vs. π relationships of the samples prepared with different processes. On the basis of the π value, substrate concentration, and the temperature dependence of the UV spectra, fluorescence excitation and emission spectra, the chromophores of 1, 2 show the formation of aggregates in ground state at high π owing to the hydrophobic interaction. The m states consist of a supersaturated solution with aggregates, whereas the s states are suspended microcrystals or micro‐oil‐droplets with aggregates. The conformations of the molecules in the aggregates were discussed. Single crystal X‐ray structure of 2 is reported.
The crystal structure and conformation of 15‐phenyl‐bicyclo[10.3.0]pentadec‐1(12)‐en‐13‐one
Authors: Xiao‐Lan Wang , Jie‐You Xue , Zhong Hu , Shi‐Xiong Tang , Ru‐Ji Wang
Published: April 2011

The title compound has been synthesized and its crystal structure determined by X‐ray crystallographic method. The crystal is monoclinic, space group C2/c, with unit cell dimensions a=19.260 (3), b=11.217 (1), c=15.997 (1) Å; β=92.08 (2)° and Z=8.

This is the first crystal structure determined in the series of bicyclo[10.3.0]pentadec‐1(12)‐en‐13‐one derivatives. The structure and the conformation of the cis‐cyclododecene moiety in this compound is demonstrated to be closely similar to the lowest energy conformer [lene 2333].
Theoretical studies on structure‐property relationships of cellulose and nitrocellulose: I. Conformation, stability and conductivity
Authors: He‐Ming Xiao , Jian‐Fen Fan , Yong‐Fu Li
Published: April 2011

The banding and electronic structures of a series of long‐chain macromolecules of cellulose, 2‐, 3‐, 6‐mononitrocellulose, 2,3‐,2,6‐, 3,6‐dinitrocellulose and trinitrocellulose as well as their structural units (i.e. single‐, double‐ or three‐ring systems) have been calculated by both the EH and CNDO/2 methods. The increase of molecular total energies is consistent with the decrease of their stabilities at the three conformations of gg, gt and tg. The Mulliken bond order of O—NO2 bond is the smallest in each molecule at any of the three conformations, which indicates that this bond is the weakest, and supports the view of initial homolytic cleavage of O—NO2 bond on slow thermal decomposition. The band gap at the edge of the first Brillouin zone far surpasses 5 eV for cellulose, and is less than 3 eV for mono‐, di‐, and trinitrocellulose. The results show that cellulose is a typical insulator, as we know, and it can be predicted that nitrocellulose has electric conductivity similar to that of semiconductor.
Theoretical studies on ammonia oxide and its unimolecular reactions
Authors: Yun‐Zhu Han , De‐Zhong Zhu , Cheng‐Da Zhao
Published: April 2011

The unimolecular reactions of ammonia oxide H3NO, isomerization and dehydrogenation, are investigated by ab initio MO calculations with the 4‐31G basis set. The geometries and energies of the reactant, transition states and products have been determined on the singlet potential energy surface. The reaction ergodography along the intrinsic reaction coordinate (IRC) for the two reactions have been performed. The vibrational frequency correlation diagram of the two reactions are analyzed along the IRC.
A study on hydrolytic polymerization of lanthanide ions
Authors: Qin‐Hui Luo , Meng‐Chang Shen , Xin‐Lu Bao , Yi Ding , An‐Bang Dai , An‐Pang Tai
Published: April 2011

Experimental data of hydrolytic polymerization of lanthanide ions in aqueous solution were treated by graphic method, computer fitting and pq analysis, species present were ascertained and hydrolysis constants obtained. Ln (OH)2+ and Ln2 (OH)24+ predominated in the species of all hydrolysis products. When the first and the second hydrolysis constants were plotted against radii and effective nuclear charge of lanthanide ions, the curves obtained conformed with the “three‐division groups” rule. Correlation between hydrolysis constants of Ln2 (OH)24+ and other hydrolysis constants is linear.

Using the above empirical correlations we calculated hydrolysis constants of all lanthanide ions and obtained satisfactory results which showed good regularity for hydrolysis of lanthanide ions and thus systematized all data of the reaction.
Conformational study of L‐lysine in aqueous solution by lanthanide shift probes
Authors: Ji‐Min Ren , Feng‐Kui Pei , Wen‐Yun Wang
Published: April 2011

Conformation of L‐lysine in aqueous solution was investigated by lanthanide shift probes (Dy, Ho, Er, Tm and Yb). Reilley's method was employed to separate the contact and dipolar components of the 13C paramagnetic shifts. This study reveals that Cα shift has the largest contact contribution while the other carbon shifts are dominated by the dipolar contribution. The average overall conformation of L‐lysine in aqueous solution is extended with the molecular backbone in trans form. In the complex, lanthanide ion coordinates to the carboxyl group with Ln—O bond length 2.2 Å and the whole ligand is located outside the zero‐dipolar shift cone of the lanthanide ion. The electronic spin density distribution on the ligand nuclei shows that the spin polarization is the predominant mechanism of the contact interaction for nuclei in close proximity to the bound lanthanide ion.
Photochemistry of endo and exo electronic configurations of biphenylyl methyl propanal
Authors: Guo‐Sheng Wu , He‐Qun Yin
Published: April 2011

Both direct and sensitized irradiations of the endo title compound lead to a decarbonylation product, 4‐isopropylbiphenyl, via Norrish Type 1 reaction, while the exo isomer gives a carbene intermediate and subsequently formaldehyde 2‐biphenylyl isopropyl hemiacetal, which in turn gradually decomposes to dimethyl phenylbenzyl alcohol at room temperature. The triplet pathway dominates the photoreaction of the exo isomer. The singlet and triplet lifetimes of the reactant are found to be 0.29 ns and 5.4 μs, respectively, 3(n, x*), 1(n, x*), 3(x, x*) electronic configurations of the exo isomer and 3(x, x*) of the endo isomer are photochemically active, but 1(x, x*) of the endo isomer shows indirect photoreactivity.
Palladium‐catalyzed cross‐coupling reaction of phenyl fluoroalkanesulfonates with organometallics
Authors: Qing‐Yun Chen , Ya‐Bo He
Published: April 2011

The palladium‐catalyzed cross‐coupling reaction of phenyl fluoroalkanesulfonates with organozinc, organotin and organoaluminum reagents in the presence of lithium chloride takes place to afford alkylbenzenes in good yields. However, the coupling reaction with organolithium and Grignard reagents proceeds unsatisfactorily with poor regioselectivity. On the basis of the isolation of an oxidative addition product of phenyl fluoroalkanesulfonate to palladium, a catalytic cycle in the reaction is suggested.
Synthesis and comparative study of reactivities of δ‐lactone, estor group and oxazinone ring in coumarin derivatives towards carbon or nitrogen nucleophiles
Authors: El‐Kafrawy  , Soliman  , Baker  , Mohamed  , El‐Kady
Published: April 2011

Condensation of methyl 7‐methylcoumarin‐4‐acetate (2) with primary amines and with anthranilic acid gave 7‐methyl‐2‐oxo‐N‐aryl‐2H‐[1]‐benzopyran‐4‐acetamide (4a—d) and (7), respectively. Compound 7 underwent cyclization to give 2‐(7‐methyl‐2‐oxo‐2H‐[1]‐benzopyran‐4‐yl)‐methyl‐4H‐3,1‐benzoxazin‐4‐one (3). The reaction of 3 with aromatic amines gave the corresponding quinazolone derivatives 5 which tautomerises to the thermodynamically more stable isomer 6, whereas its reaction with Grignard reagents and aromatic aldehydes gave 8a, 8b, and 9a, 9b, respectively.
The synthesis of fluorine‐containing porphyrins
Authors: Wei‐Yuan Huang , Wu‐Ping Ma
Published: April 2011

The synthesis of polyfluoroalkoxyl substituted tetrakisphenylporphyrin is reported. The reaction is carrying out using Lewis acid BF3·OEt2 as catalyst and p‐chloranil as oxidant. The yields of the porphyrins are about 30–40%.
Investigation on the eigenvalue‐equation problem of molecular crystals and polymers
Authors: Yan Ji‐Min , Zhang Qi‐Yuan
Published: April 2011

One‐dimensional periodic system, such as molecular crystal and polymer, can be expressed as … ABABAB … structure, where A and B stand for a complete molecule or a part of a molecule. When (AB) is taken as a structure unit, one can obtain the complex generalized eigenvalue‐equation HAB (k) ‐ CAB (k) ‐ SAB (k) CAB (k) EAB (k); and if (BA) is taken as a structure unit, the corresponding eigenvalue‐equation is HBA (k) CBA (k) ‐ SBA (k) CBA (k) EBA (k). The relationship between the two equations has been investigated. The results of theoretical analysis are \documentclass{article}\pagestyle{empty}\begin{document}$ E_m^{{\rm BA}} (k) = E_m^{{\rm AB}} (k);\quad C_{j_{\rm a} m}^{{\rm BA}} (k) - C_{j_{\rm a} m}^{{\rm AB}} (k) \cdot \exp (i\Delta \phi) $\end{document} and \documentclass{article}\pagestyle{empty}\begin{document}$ C_{j_{\rm b} m}^{{\rm BA}} (k)\quad C_{j_{\rm b} m}^{{\rm AB}} (k) \cdot \quad \exp [i(k.R_{ - 1} + \Delta \phi)] - C_{j_{\rm b} m}^{{\rm AB}} (k) \times \exp (i\Delta \phi) $\end{document} where ja and jb are the index number of atomic orbitals within (A) and (B) respectively, and m stands for the index number of crystal or polymer orbitals. This result has been verified by the concrete calculation of three periodic systems: (1) hydrogen‐molecular chain, …H (A) H (B) … H (A) H (B) …, (2) polyphenylene, … (A) (B) (A) (B) …, where (A) and (B) stand for =C (CH=)2 and ( HC)2 C= respectively, and (3) the TCNQ molecular column, … TCNQ (A). TCNQ (B) … TCNQ (A). TCNQ(B) … . The results can be generalized to two‐ and three‐dimensional systems straightforwardly.
A description of nitrogen‐nitrogen bond in terms of charge distributions
Authors: Cao Wei‐Liang , Marshall T. C. , Bader R. F.W.
Published: April 2011

A theoretical analysis of properties of the shared interactions between two neighbouring nitrogen atoms in a variety of compounds is presented, based on properties of charge distributions derived from 6‐31 ++G** wave functions.

Bond is characterized in terms of its bond order, bond ellipticity and the quantity of Laplacian of ρ at the bond critical point. The difference between the bond path angle and the corresponding geometrical angle provides a measure of the degree of relaxation for the charge density away from the geometrical constraints imposed by the nuclear framework. Comparisons have been made between the nitrogen‐containing compounds and isoelectronic hydrocarbons.

Values of the NN bond energies, based on the properties of NN bond interatomic surface, are determined in three schemes.
A study of differential potentiometric stripping analysis for lead and cadmium with Nafion coated carbon fibre electrode
Authors: Dong Shao‐Jun , He Jun , Wang Yu‐Dong
Published: April 2011

The differential potentiometric stripping analysis (DPSA) with Nafion coated carbon fibre electrode has been studied, and a method to determine lead and cadmium in urine directly has been attempted. The effect of various experimental parameters on the DPSA response is discussed. The experimental conditions include 0.2M sodium perchlorate, deposition potential of −1.0 or −1.1 V and using 20 ppm mercuric ion as oxidizing agent. The response of the signal is in linear relation with the concentrations of lead and cadmium respectively up to 0.5 ppm. The electrode coated with Nafion film alleviates the interference from organics in urine samples.
1H and 13C NMR studies of lanthanide complex with 5‐sulfosalicylic acid
Authors: Ren Ji‐Min , Pei Feng‐Kui , Wang Wen‐Yun
Published: April 2011

In this paper, paramagnetic shifts have been measured for all 1H and 13C nuclei of 5‐sulfosalicylic acid (SSA) in the presence of the lanthanide ions in the second half of the series. The ligand forms isostructural complexes with these ions in aqueous solution. The separation of LISs was carried out by the use of the Reilley method and the calculated dipolar shifts were used to simulate the coordination structure of the complex. The result reveals that SSA is coordinated to lanthanide ion via two oxygens, one from the carboxylic group and the other from the phenolic group with Ln–O bond lengths equal to 2.47 Å. The lanthanide ion lies on the benzene plane and the carboxylic group is twisted 20° from the benzene ring. Of all the nuclei examined, those in the six‐membered chelate ring experience significant dipolar interactions and contact interactions. Small |G/A| ratios were obtained for two protons five bonds away from the central lanthanide ion, which shows that the number of bonds alone cannot be used as a criterion for neglecting contact shifts in aromatic ligand.
Structural studies on rare earth carboxylates: I. Studies on the crystal structure of tris(neopentanoato)‐tris(neopentanoic acid)neodymium(III) dimer, [NdA3(HA)3]2
Authors: Zhang De‐Long , Huang Chun‐Hui , Xu Guang‐Xian , Pan Zuo‐Hua
Published: April 2011

The title complex was synthesized and its structure was determined. The crystal is monoclinic with space group P21/n. Unit cell parameters are as follows: a=16.474(8), b=12.425(4), c=20.844(12)Å, β=109.27(4)°, Z=4. In each dimer, the two Nd atoms are connected through two pairs of bridging neopentanoate anions. The two carboxyl groups in each pair are in opposite position to Nd atom which are coplanar with them and the two planes are perpendicular with each other. In the complex each Nd atom is further coordinated with three neopentanoic acid molecules and one monodentate neopentanoate anion. The central atom is octa‐coordinated in a square‐antiprism arrangement.
Perfluoroalkylation of aromatic compounds with perfluoroalkyl radical generated from the oxidation of sodium perfluoroalkanesulfinate
Authors: Huang Wei‐Yuan , Xie Yuan
Published: April 2011

Sodium perfluoroalkanesulfinates [RfSO2Na(1), Rf = Cl (CF2)n; a, n = 4; b, n = 6; c, n = 8] on oxidation with various single electron oxidizing agents, such as Mn (OAc)3 · 2H2O and Ce (SO4)2, yielded perfluoroalkyl radicals capable of perfluoroalkylating aromatic compounds to give a mixture of o‐and p‐monoperfluoroalkylated products. Thus, this reaction provides a new method for the synthesis of o‐and p‐monoperfluoroalkyl substituted aromatic compounds.
Diastereoselective alkylation of the ( + )‐ketopinic acid ketimine derived from benzylamine
Authors: Deng Jin‐Gen , Hu Wen‐Hao , Liu Gui‐Lan , Mi Ai‐Qiao , Jiang Yao‐Zhong
Published: April 2011

Alkylation of the ketimine 2 obtained from condensation of (+)‐ketopinic acid and benzylamine with a variety of alkylating agents gives the products whose trends in diastereomeric excesses (1 — 100% O.P.) appear to correlate with the structure and reactivity of electrophilic agents. Using excess n‐butyl lithium and allylic or benzylic halides, β‐alkylation occured.
Some reactions of 4‐aryl‐1 (2H)‐phthalazinones
Authors: Soliman A. Y. , Bakeer H. M. , Sayed M. A. , Islam I. , Mohamed A. A.
Published: April 2011

The behaviors of 4‐aryl‐1 (2H)‐phthalazinones (1a–c) toward carbon nucleophiles (Grignard reagents) and secondary amine under Mannich conditions as well as the nucleophilic substitution reaction on chlorophthalazine derivatives have been studied.
Studies on sulfinatodehalogenation: XVIII. The reaction of perfluoroalkyl iodides with α‐methylene cyclic ethers
Authors: Huang Wei‐Yuan , Zhang Han‐Zhong , Zhuang Jin‐Lian
Published: April 2011

Perfluoroalkyl iodides reacted with various α‐methylene oxacycloalkanes in the presence of sodium dithionite to give ring opening adducts. The reaction provided an efficient method for the syntheses of polyfunctional organofluorine compounds.
Asymmetric carbonyl addition with the homochiral ketimine derived from (+) or (−)‐pinanone and benzylamine
Authors: Mi Ai‐Qiao , Chen Yuan‐Wei , Wang Jing , Yang Gui‐Shu , Jiang Yao‐Zhong
Published: April 2011

The carbonyl addition of the pinanone ketimine derived from (+) or (−)‐2‐hydroxy‐pinan‐3‐one and benzylamine has been studied and the optically active α,β‐substituted‐β‐aminoethanol derivatives were obtained in good chemical yields (36.5‐69.5%) with optical purity ranging from 1.4% to 99.9%.
Evidence for the Existence of a Specific G Protein‐Coupled Receptor Activated by Guanosine
Authors: Volpini Rosaria , Marucci Gabriella , Buccioni Michela , Dal Ben Diego , Lambertucci Catia , Lammi Carmen , Mishra Ram C. , Thomas Ajiroghene , Cristalli Gloria
Published: April 2011

Guanosine, released extracellularly from neurons and glial cells, plays important roles in the central nervous system, including neuroprotection. The innovative DELFIA Eu‐GTP binding assay was optimized for characterization of the putative guanosine receptor binding site at rat brain membranes by using a series of novel and known guanosine derivatives. These nucleosides were prepared by modifying the purine and sugar moieties of guanosine at the 6‐ and 5′‐positions, respectively. Results of these experiments prove that guanosine, 6‐thioguanosine, and their derivatives activate a G protein‐coupled receptor that is different from the well‐characterized adenosine receptors.
Relative input strength rapidly regulates dendritic structure of chick auditory brainstem neurons
Authors: Sorensen Staci A. , Rubel Edwin W.
Published: April 2011

Competition between presynaptic inputs has been suggested to shape dendritic form. This hypothesis can be directly tested on bitufted, auditory neurons in chicken nucleus laminaris (NL). Each NL neuron contains two relatively symmetrical dendritic arbors; the dorsal dendrites receive excitatory glutamatergic input from the ipsilateral ear, and the ventral dendrites receive corresponding input from the contralateral ear. To assess the effect of relative synaptic strength on NL dendrites, we used single‐cell electroporation; electrophysiology; and live, two‐photon laser scanning microscopy to manipulate both the amount and the balance of synaptic input to the two matching sets of dendrites. With simultaneous activation, both sets of dendrites changed together, either growing or retracting over the imaging period. In contrast, stimulation of only one set of dendrites (either dorsal or ventral) resulted in the unstimulated dendrites losing total dendritic branch length, whereas the stimulated dendrites exhibited a tendency to grow. In this system, balanced input leads to balanced changes in the two sets of dendrites, but imbalanced input results in differential changes. Time‐lapse imaging revealed that NL dendrites respond to differential stimulation by first decreasing the size of their unstimulated dendrites and then increasing the size of their stimulated dendrites. This result suggests that the relative activity of presynaptic neurons dynamically controls dendritic structure in NL and that dendritic real estate can rapidly be shifted from inactive inputs to active inputs. J. Comp. Neurol. 519:2838–2851, 2011. © 2011 Wiley‐Liss, Inc.
The application and diagnostic utility of immunocytochemistry on direct smears in the diagnosis of pulmonary adenocarcinoma and squamous cell carcinoma
Authors: Roh Michael H. , Schmidt Lindsay , Placido Jeremiah , Farmen Sara , Fields Kristina L. , Courey Anthony J. , Arenberg Douglas A. , Knoepp Stewart M.
Published: April 2011

The importance of subclassifying pulmonary nonsmall cell carcinoma (NSCLC) in cytologic material is becoming increasingly paramount. Occasionally, cell blocks traditionally used for ancillary studies are sparsely cellular or acellular. Hence, we investigated the diagnostic utility of immunocytochemistry for Napsin‐A, TTF‐1, and p63 on direct smears of NSCLC. Immunohistochemistry for Napsin‐A was initially tested on a tissue microarray (TMA) composed of pulmonary adenocarcinoma. Subsequently, in 25 cases, immunocytochemistry for Napsin‐A, TTF‐1, and p63 was performed on cytologic direct smears. Smears were prepared from tumor cells scraped from lung resection specimens (n = 10), endobronchial ultrasound‐guided transbronchial fine‐needle aspirates (n = 13), and pelleted cell material from pleural effusions (n = 2). Immunohistochemistry utilizing the TMA revealed Napsin‐A positivity in 73% of pulmonary ADCs. Next, immunocytochemistry on direct cytologic smears demonstrated a Napsin‐A(+)/TTF‐1(+) immunophenotype in 15 of 18 adenocarcinomas; p63 was completely negative (n = 12) or only focally positive (n = 3) in these 15 adenocarcinomas. The remaining three adenocarcinomas were negative for all three markers. All six squamous cell carcinomas were Napsin‐A(−)/TTF‐1(−) and diffusely p63(+). In conclusion, direct smears represent a feasible and robust source of cellular material for immunocytochemical studies to diagnose pulmonary ADC and SQC. Our method allows the cytologist to confirm on site that material for diagnostic immunocytochemistry is present thereby serving as a safeguard in instances where the cell block is of insufficient cellularity. Diagn. Cytopathol. 2012. © 2011 Wiley Periodicals, Inc.
Inflammatory myxohyaline tumor of distal extremities:Cytologic findings in a lesion simulating a high‐grade myxoid sarcoma
Authors: Layfield Lester J.
Published: April 2011

Fine‐needle aspiration cytology has been shown to be useful in the diagnosis of lesions of the distal extremities with an accuracy of ∼70% for the specific diagnosis of tumors of the hand. Despite this accuracy, some cases may be misinterpreted as to the type of lesion present. A 34‐year‐old male presented with a 1.5 cm mass in the soft tissue of his right middle finger. Fine‐needle aspiration (FNA) was performed and produced cellular smears with a myxoid background. The majority of cells were of a short “spindle” or polygonal shape but a number of large pleomorphic cells were also present. A diagnosis of pleomorphic myxoid sarcoma was given. Subsequent incisional biopsy revealed an inflammatory myxohyaline tumor of the distal extremities (IMTDE). FNA, core needle biopsy, and even small incisional biopsies may result in misdiagnosis of IMTDE as pleomorphic sarcoma, an inflammatory condition or even Hodgkin's disease. Careful attention to the myxoid background, prominence of inflammatory cells, nature of the pleomorphic cells, and location of the lesion should favor the diagnosis of IMTDE. Diagn. Cytopathol. 2012. © 2011 Wiley Periodicals, Inc.
pKa modelling and prediction of drug molecules through GA‐KPLS and L‐M ANN
Authors: Noorizadeh H. , Farmany A. , Noorizadeh M.
Published: April 2011

Genetic algorithm and partial least square (GA‐PLS), kernel PLS (GA‐KPLS) and Levenberg‐ Marquardt artificial neural network (L‐M ANN) techniques were used to investigate the correlation between dissociation constant (pKa) and descriptors for 60 drug compounds. The applied internal (leave‐group‐out cross validation (LGO‐CV)) and external (test set) validation methods were used for the predictive power of models. Descriptors of GA‐KPLS model were selected as inputs in L‐M ANN model. The results indicate that L‐M ANN can be used as an alternative modeling tool for quantitative structure–property relationship (QSPR) studies. Copyright © 2011 John Wiley & Sons, Ltd.
Determination of berberine in pharmaceutical preparations using acidic hydrogen peroxide–nitrite chemiluminescence system
Authors: Liang Yao‐Dong , Yu Chun‐Xia
Published: April 2011

A stronger chemiluminescence (CL) was observed when hydrogen peroxide was mixed with nitrite and berberine in sulfuric acid solution. The stronger CL originated from peroxidation of berberine by peroxynitrous acid that was synthesized online by the mixing of acidic hydrogen peroxide solution with nitrite solution in a flow system. The emitting species was excited state oxyberberine, a peroxidized product of berberine. Based on the stronger CL, a flow injection CL method for the determination of berberine was proposed. Under optimum experimental conditions, the stronger CL intensity was linearly related to the concentration of berberine over the range of 2.0 × 10−7–2.0 × 10−5 mol L−1. The limit of detection (s/n = 3) was 6.2 × 10−8 mol L−1. The proposed method has been evaluated by analyzing berberine in pharmaceutical preparations. Copyright © 2011 John Wiley & Sons, Ltd.
Moderators of dialectical behavior therapy for binge eating disorder: Results from a randomized controlled trial
Authors: Robinson Athena Hagler , Safer Debra L.
Published: April 2011

Objective:

Investigate moderators of a randomized clinical trial of group Dialectical Behavior Therapy for Binge Eating Disorder (DBT‐BED) compared to an active comparison group control (ACGT) on the post‐treatment outcome of binge frequency after twenty 2‐h weekly sessions.

Method:

Moderation analyses.

Results:

Participants were 101 adults with BED [mean (SD) age, 52.2 (10.6) years and BMI, 36.4 (8.6)]. Analyses identified two moderators of post‐treatment outcome. Participants with (1) Avoidant Personality Disorder or (2) an earlier onset of overweight and dieting (<15 years old) evidenced significantly worsened outcome when treated with ACGT versus DBT‐BED.

Discussion:

Participants with certain indicators of higher baseline pathology respond better to DBT‐BED than ACGT at post‐treatment. © 2011 by Wiley Periodicals, Inc. Int J Eat Disord 2012.
Pax6‐positive müller glia cells express cell cycle markers but do not proliferate after photoreceptor injury in the mouse retina
Authors: Joly Sandrine , Pernet Vincent , Samardzija Marijana , Grimm Christian
Published: April 2011

In lower vertebrates, such as fish, Müller glia plays an essential role in the restoration of visual function after retinal degeneration by transdifferentiating into photoreceptors and other retinal neurons. During this process, Müller cells re‐enter the cell cycle, proliferate, and migrate from the inner nuclear layer (INL) to the photoreceptor layer where they express photoreceptor‐specific markers. This process of Müller cell transdifferentiation is absent in mammals, and the loss of photoreceptors leads to permanent vision deficits. The mechanisms underlying the failure of mammalian Müller cells to behave as stem cells after photoreceptor degeneration are poorly understood. In the present study, we show that photoreceptor injury induces migration of PAX6‐positive Müller cell nuclei toward the outer part of the INL and into the inner part of the outer nuclear layer. These cells express markers of the cell cycle, suggesting an attempt to re‐enter the cell cycle similarly to lower vertebrates. However, mouse Müller cells do not proliferate in response to photoreceptor injury implying a blockade of the S‐phase transition. Our results suggest that a release of the S‐phase blockade may be crucial for Müller cells to successfully transdifferentiate and replace injured photoreceptors in mammals. © 2011 Wiley‐Liss, Inc.
Comorbidity and the rate of cognitive decline in patients with Alzheimer dementia
Authors: Solomon Alina , Dobranici Letitia , Kåreholt Ingemar , Tudose Cătălina , Lăzărescu Mircea
Published: April 2011

Objective

This study aimed to investigate the impact of comorbidity on cognitive and functional decline in patients with Alzheimer dementia (AD).

Methods

One hundred and two AD outpatients examined at the Psychiatry Department of the CF2 Polyclinic in Bucharest, Romania and re‐evaluated after 2 years. Comorbidity was rated using the Cumulative Illness Rating Scale for Geriatrics (CIRS‐G).

Results

Baseline mean age (SD) was 75.4 (8.2) years, median CDR (range) was 2 (1–3), and mean MMSE (SD) 14.2 (4.9). MMSE declined to 11.2 (4.8) during follow‐up. Baseline mean total CIRS‐G score (SD) was 13.8 (5.4), median number of endorsed categories (range) was 8 (1–14), and mean severity index (SD) 1.9 (0.4). Main comorbidity areas were cardiovascular, ear, nose and throat, genitourinary, musculoskeletal/integument, and neurological. Severity of comorbidity increased with dementia severity (p < 0.001). Baseline comorbidity was related to increased rate of cognitive decline; truncated regression coefficients (p‐values) were 0.01 (0.02) for CIRS‐G total score, and 0.15 (0.006) for severity index (controlled for age, sex, education, and AD treatment). Faster cognitive decline was associated with faster functional decline: OR (95% CI) was 5.2 (1.9−13.6) for increased rate of ADL change and 3.8 (1.0−14.1) for increased rate of IADL change (controlled for age, sex, education, AD medication, and comorbidity). Comorbidity tended to increase functional decline; however, the associations were not statistically significant.

Conclusions

In this group of patients with AD, comorbidity increased the rate of cognitive decline. Considering comorbidity instead of focusing on separate conditions may be more helpful in managing AD. Copyright © 2011 John Wiley & Sons, Ltd.
Cultural adaptation of evidence‐based practice utilizing an iterative stakeholder process and theoretical framework: problem solving therapy for Chinese older adults
Authors: Chu Joyce P. , Huynh Loanie , Areán Patricia
Published: April 2011

Objectives

Main objectives were to familiarize the reader with a theoretical framework for modifying evidence‐based interventions for cultural groups, and to provide an example of one method, Formative Method for Adapting Psychotherapies (FMAP), in the adaptation of an evidence‐based intervention for a cultural group notorious for refusing mental health treatment.

Methods

Provider and client stakeholder input combined with an iterative testing process within the FMAP framework was utilized to create the Problem Solving Therapy—Chinese Older Adult (PST‐COA) manual for depression. Data from pilot‐testing the intervention with a clinically depressed Chinese elderly woman are reported.

Results

PST‐COA is categorized as a ‘culturally‐adapted’ treatment, where core mediating mechanisms of PST were preserved, but cultural themes of measurement methodology, stigma, hierarchical provider‐client relationship expectations, and acculturation enhanced core components to make PST more understandable and relevant for Chinese elderly. Modifications also encompassed therapeutic framework and peripheral elements affecting engagement and retention. PST‐COA applied with a depressed Chinese older adult indicated remission of clinical depression and improvement in mood. Fidelity with and acceptability of the treatment was sufficient as the client completed and reported high satisfaction with PST‐COA.

Conclusions

PST, as a non‐emotion‐focused, evidence‐based intervention, is a good fit for depressed Chinese elderly. Through an iterative stakeholder process of cultural adaptation, several culturally‐specific modifications were applied to PST to create the PST‐COA manual. PST‐COA preserves core therapeutic PST elements but includes cultural adaptations in therapeutic framework and key administration and content areas that ensure greater applicability and effectiveness for the Chinese elderly community. Copyright © 2011 John Wiley & Sons, Ltd.