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A capillary electrophoresis method has been developed for the determination of brucine in strychnos. The analytical conditions were optimized after investigating the effects pH and concentration of buffer. Under optimized conditions (20 mmol/L NaH2PO4-Na2HPO4, pH=6.0, 20 kV, 254 nm,), the brucine was separated in 5 min.

In this paper, using capillary zone electrophoresis method determined Vitamin C content in brown rice. 20 mmol/L borax solution and 20% acetonitrile concentration, 20kV voltage, 254 nm UV detection wavelength was chosen for electrophoretic analysis condition. Measured vitamin C content in brown rice was 0.043 mg/g (RSD=7.1%) (n=7).

In this work, the new capillary zone electrophoresis method is used for the determination of the content of gallic acid in jianmin throat tablet. Under the 20 mmol/L borate (pH=9.44), valid separation of gallic acid is obtained in jianmin throat tablet and the content of gallic acid is 0.7096 mg/g (RSD=5.4%) (n=5). The average recovery of gallic acid is 112.4% (RSD=8.4%)(n=4). The method is simple and rapid.

The Tb complex C6H14O19Tb2has been synthesized from a hydrothermal reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. The Tb atom is coordinated by nine O atoms. The molecular structure stabilized by the O-H…O hydrogen-bonding interactions.

A novel Ga complex (NH4)Ga(C7H3NO4)2 has been synthesized from a solution reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. The Ga atom is six-coordinated by two N atoms and four O atoms from two 2,6-pyridine dicarboxylic acid anions. The crystal packing is stabilized by O-H...N hydrogen bonding interactions.

In this paper, the new capillary zone electrophoresis method was studied and the content of the naringenin was determined in xiao’er jindan tablet. The optimized experiment condition was 30mmol/L borate buffer (pH=10.00), 20 kV, 254 nm. The content of naringenin was 0.569mg/g, RSD=1.67%(n=5). The average recovery of naringenin was 85.6%(RSD=7.6%)(n=4). The new method was provided for the quality controling of xiao’er jindan tablet medicine.

In this paper, using capillary zone electrophoresis method determined gallic acid content in Paeonia lactiflora Pall. Under the condition of buffer solution containing 20 mmol/L Na2B4O7, effective separation of components to be tested was realized. Measured content of gallic acid in Paeonia lactiflora Pall was 1.15 mg/g (RSD=4.28%) (n=6), the average recovery was 88.48% (n=5). This method is simple and fast.

High performance capillary zone electrophoresis (HPCE) was used in this text to determine the content of ferulic acid in a ready-made Chinese herbal medicine called AI-FUNUAN-GONG (in pills). Electrophoretic separation conditions: Uncoated fused silica capillary column (75um×49/58cm), injection height 7.5cm, 30mmolL-1 borax solution, separation voltage 20kV, injection time 10s, detection wavelength 315 nm, experimental temperature 20°C.Linearity was kept in the concentration ranging from 1~62.5 mg·L-1 of ferulic acid with correlation coefficient of 0.970. The average recovery was 97.541% and RSD value was 6.57%. Sample content of ferulic acid was 0.0715mg/g. This method has the advantages of strong specificity, simpleness, speediness, accurate results and good repeatability in separation and it is useful for determination of ferulic Acid in AI-FU-NUAN-GONG Pills.

The Tb complex C9H24O21Tb2has been synthesized from a hydrothermal reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. The Tb atom is coordinated by nine O atoms. The molecular structure stabilized by the O-H…O hydrogen-bonding interactions.

In this paper, using capillary zone electrophoresis method determined gallic acid content in terminalia. Under the condition of buffer solution containing 20 mmol/L Na2B4O7, effective separation of components to be tested was realized. Measured content of gallic acid in terminalia was 25.36 mg/g (RSD=6.8%) (n=6), the average recovery was 87.6%. This method is simple and fast.

A novel praseodymium complex C5H13O11Pr has been synthesized from hydrothermal reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. The Pr1 atom is nine coordinated by nine O atoms. The crystal packing is stabilized by O-H...O hydrogen bonding interactions.

In the title compound, C21H9Ba2N3O12Sr, is prepared from a hydrothermal reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. The compound crystallize in Monoclinic, system with space group and cell parameters, C2/c, a=22.668 Å, b=10.937 Å, c=9.05 Å, α=γ=90°, β=90.582°, V=2243.6 Å3. The crystal packing is stabilized by O-H...O and O-H...N hydrogen bonding interaction.

A novel Ni metal complex H26Mo6N2NiO30has been synthesized from hydrothermal reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. H26Mo6N2NiO30, Monoclinic, P2(1)/c. a = 11.3487(14) Å, b = 11.0823(13) Å, c = 11.9350(16) Å. alpha=gamma= 90°. beta= 108.542(2)°. V= 1423.1(3) Å3. It is also striking that the structure of title compound exhibits extensive hydrogen-bonding interactions among water molecules, ammonium cation, and oxygen atoms in the heteropolyanion.

A novel Eu metal complex C14H19EuN2O14has been synthesized from hydrothermal reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. The Eu atom is nine-coordinated by two N atom and seven O atoms. The crystal packing is stabilized by O-H...O hydrogen bonding interactions

Soybean polypeptide mixture was decolorized by adopting activated carbon adsorption decolourization process. Anion/cation exchange process was used in the desalination processing of soybean polypeptide. It was showed that excellent decolorizing and desalting effect to soybean peptide solution was gained in the decolourization and desalination process adopted in this experiment. Optimal dosage of activated carbon was 1.2% solution amount (w/w). After decolorizing soybean polypeptide solution color was yellow. Proportion of anion resin and cation resin of ion exchange resin was 2:3(V/V). The volume of solution processed was 5 times as the volume of anion exchange resin. After desalination processing, ash content of soybean peptide solution reduced to 2.11% (dry basis), salinity decreased by 86%, on the other hand taste of soybean polypeptide was lite.

Soybean protein Alcalase hydrolysate was further hydrolyzed by adopting Flavourzyme. From this further hydrolysis reaction, bitter of soybean polypeptide mixture was reduced distinctly. The optimal hydrolysis conditions of Flavourzyme was determined as that pH was 7.0 at temperature 50°C and E/S(ratio of enzyme and substrate) was 20LAPU/g. Bitter taste value was reduced to 2 after Flavourzyme hydrolysis reaction for 2 hours in optimal hydrolysis conditions. The change of molecular weight distribution range from Alcalase hydrolysate to Flavourzyme hydrolysate was not obvious. DH (Degree of hydrolysis) of soybean protein hydrolysate was increased to 24.2% which was improved 3.5% than Alcalase hydrolysate. Protein recovery proportion was increased to 73.2% which was improved 0.8% than Alcalase hydrolysate.

Emulsion copolymerization of acrylamide (AM) and cationic monomer DMC (methyl acrylacyl oxyethyl trimethyl ammonium chloride) was studied. A series of cationic polyacrylamide (CPAM) emulsion were synthesized using Water in water emulsion polymerization. Influence of polymerization conditions such as cationic monomer (DMC) ratio, reaction time, the initiator dosage on synthetic product strengthening effect to paper pulp was studied. It was showed that the CPAM emulsion optimal synthetic conditions was that AM monomer second adding amount was 60% AM total amount, ammonium persulfate initiator and sodium hydrogen sulfite initiator dosage was 0.138g and 0.03g respectively, mass ratio of DMC and AM was 15:85, reaction time was 7 hours. When the dosage of CPAM emulsion was 1.0% to absolute dry bleached wheat straw pulp, distinct strengthening effect was acquired, tensile index and tearing index of handsheet was increased by 27.2% and 26.8% respectively.

Application in paper pulp as dry strengthening agent of homemade water in water cationic polyacrylamide (CPAM) emulsion was studied. Good collaborative effect was achieved when Homemade CPAM was used in bleached wheat straw pulp with strengthening agent E and with cationic additives L as paper pulp strengthening agent. It was also showed that distinct strengthening effect was obtained when homemade CPAM emulsion was applied in mixture of wood pulp which was needle bleached kraft pulp (NBKP) and straw pulp, breaking length and tearing index of hand sheet made of mix pulp was respectively increased by 22.2% and17.0% when the dosage of CPAM was 0.8% of dry fiber. Through analysis of handsheet section scanning electron microscopy (SEM) photos, strengthening mechanism of CPAM emulsion to paper pulp was preliminary studied.

Chloride ions were harmful to the performance of the concrete.Admixture mineral had been replaced part of cement in high performance concrete to improve the durability and chloride resistance of the concrete.In this paper,the compressive strength of the concrete with admixture mineral and without admixture mineral had been measured cured after 28 days. The results had been shown that the compressive strength of the concrete without admixture mineral is lower than the one with admixture mineral after 28ds’and 56ds’ immersing in 5%NaCl solution. The quantities of electricity through the concretes with 30% admixture mineral were lower than the benchmark concretes. The current of C30 and C40 concretes with admixture mineral was lower than the benchmark concretes.The concrete with admixture mineral had been eroded lower than the one without admixture mineral.

Emulsion copolymerization of methyl acrylate, styrene, acrylamide, acrylonitrile and homemade cationic monomer was studied. A series of clean cationic polymethyl acrylate emulsion were synthesized using no soap emulsion polymerization. Influence of polymerization conditions such as cationic monomer ratio, electrolyte addition amount, the dosage of initiator on synthetic latex performance and the strengthening effect to paper pulp was studied. It was showed by experimental results that sample No.3 which particle size and zeta potential was 0.142 μm and +29.2 mv respectively was the optimal sample latex. When the dosage of latex No.3 was 1.0% to absolute dry pulp, tensile index and ring crush index of paper was increased by 14.6% and 17.8% respectively.

Cationic polymethyl acrylate emulsion which was prepared with no soap emulsion polymerization was used in bleached wheat straw pulp as papermaking retention agent. The main influence factors on retention effect, such as dosage of polymethyl acrylate emulsion, pH value of the bleached wheat straw pulp, reaction time after adding the polymethyl acrylate emulsion and stir velocity were discussed in detail. Experimental results showed that optimal application conditions were that first step was adding cationic emulsion which dosage was 0.64% relative to dry fiber, stir velocity was 1400r/min, 90s for reaction, second step was adding anion components which dosage was 0.16% relative to dry fiber, stir velocity was 750r/min, 60s for reaction, pH value was 4.5~5.0. The cationic organic particles system has good retention aid effect which one pass retention was 96.4%.

Unsaturated polyester resin/Graphite nanosheet composites were prepared using in situ polymerization under AC electric field which was applied during composite curing to induce orientation of graphite nanosheets. Scanning electron microscopy (SEM) has been applied to demonstrate the orientation of graphite nanosheets As a result, the percolation threshold was decreased to 0.25 wt% due to the orientation of the graphite nanosheets.

Graft copolymerization of chitosan and vinyl monomer (such as acryamide and acrylic acid) and application study of the copolymer used as papermaking additive were paid more and more attention in papermaking chemical industry. Chitosan and acrylamide(AM) monomer were graft copolymerizing in inverse emulsion. Several factors such as oil-water proportion, mass ratio of chitosan and AM, emulsifier types and ratio, and initiator concentration that affect the stability of inverse emulsion were elementarily studied. Stable latex can be gained when reaction condition was that the volume ratio of oil phase and water phase was 1:1, the weight ratio of chitosan and AM was 1:8, the initiator concentration was 0.8mmol/L, the dosage of emulsification agent was 8% of the oil phase weight and the weight ratio of 1227 and OP-10 was 1:1.

Because there are cyclical phenomenons in lives so that the influence of the medicine on oscillating reaction is becoming a hotspot.The author prepares a pharmaceutical intermediate. It is 2,6-dihydroxy-4-methylpyrimidine.In this paper the influence of the pharmaceutical intermediate on BZ oscillation system have been studied at different temperature and different concentration. For instance, dropping the concentration of 0.01mol/Lpharmaceutical intermediate before and after, apparent activation energy E and E’ of the systems are 68094J/mol and 71786J/mol.Higher temperature and higher concentration,oscillating cycles and amplitude are lower.

Preservative was very necessary used in coated paper coating. Preservative was typical paper additive which was low dosage and high yield. Preservative classification, function mechanism and application technology of coated paper coating was introduced and summarized by the numbers in this paper. Finally the development direction and prospect of preservative used in coated paper coating was prospected.

Recycling of waste paper is demanded because of the shortage of forest resources, the pollution of environment and the scarcity of papermaking materials. It is important to raise the proportion of waste paper in the fiber materials in papermaking industry. Floating/washing method was used here with imported Old Newspaper (ONP) as elementary material. This article studied the deinking performances of many kinds of surfactants primarily. Among them several surfactants were picked out as deinking agent of Old Newspaper (ONP) because of their better deinking effect.

Copper zinc oxide catalysts are effective for the ambient temperature carbon monoxide oxidation and display higher specific activity than the current commercial hopcalite catalyst. We investigate the copper zinc oxide catalyst prepared by co-precipitation under different atmospheres for the oxidation of carbon monoxide at low temperatures and these systems are now worthy of further investigation.

Recycling of waste paper is one of pop topics of pulping and papermaking industry. Deinking technology is the key of recycling of waste paper. It is briefly introduced that methods of waste paper deinking and mechanism of deinking and constitute of deinking agent.

TiC/C composite fibers were prepared by vapor phase titanizing of the regular carbon fibers via chemical vapor deposition (CVD). The carbon fibers were titanized from the surface of the fiber to the core. Scanning electron microscope (SEM) and X-ray diffraction (XRD) were applied to characterize the morphology and structure of the TiC/C composite fibers. The influences of CVD reaction conditions such as temperature and reaction time on the TiC particle size and the thickness of the deposited layer were investigated. Higher temperature and longer time resulted in the growth of bigger size of the TiC crystal particles, and the particle uniformity was also decreased.

Inverse emulsion graft copolymerization of chitosan and acrylamide monomer under microwave radiation was studied. It was shown that when the microwave radiation power was 300W, the microwave radiation time was 150S, the volume ratio of oil phase and water phase was 1:1, the weight ratio of chitosan and AM was 1:7, the initiator concentration was 0.67mmol/L, the dosage of emulsification agent was 7% of the weight of oil phase and the weight ratio of Span-80 and OP-10 was 6:4, stable inverse latex could be gained. A good dry strengthening effect had been obtained by applying the above mentioned latex in wheat straw pulp as the strengthening agent. The breaking length and tearing index of paper was respectively increased by 23.5% and 15.1% when the dosage of the graft copolymer latex was 0.6%.

A new schiffbase ligand, methyl-2-pyridyl ketone benzoyl hydrazone (L), and its complexes with rare earth nitrates have been synthesized. These new complexes with the general formula of Ln(L)2(NO3)3·nH2O(where Ln = La, n = 5.5; Ce, Pr, n = 5; Nd, Eu, n = 4 ) were characterized by mass spectra, elemental analysis, IR spectra, thermal analysis, UV spectra, molar conductivity and luminescent spectra. All the complexes are stable in air. The results show that the lanthanide ion in each complex are coordinated by oxygen and nitrogen atoms of the ligand, the oxygen atoms of the nitrate and coordinated water molecules. The amide-oxygen atoms of L coordinate to the Ln ions in its keto-form. Tentative structures for the complexes have been proposed.

The reaction of 2-acetyl-2'-chloroacetanilide (L) with rare earth nitrates in CH3CH2OH followed by recrystallization in CH3CH2OH gave rise to colorless block crystals materials. The complexes and ligand were analyzed by FAB, elemental analysis(C, H, N), FT-IR spectra, TG-DTA, molar conductivity and X-ray single crystal diffraction. The fluorescence properties of ligand and the Eu (Ⅲ) complex also have been investigated. The results of crystal structure and spectral data show that the rare earth ions coordinated with oxygen and nitrogen atoms of the ligand, the nitrate and coordinated water molecules. The Eu (Ⅲ) complex material shows characteristic red emissions.

This study found that in Tris-HCl buffer, the resonance light scattering (RLS) intensity of the Eu(3+)-nicotinic acid system can be greatly enhanced by nucleic acids and the enhanced intensity is proportional to the concentration of nucleic acid in the range of 7 x 10(-8)-1 x 10(-5 ) g x mL(-1) for fsDNA, and its detection limit is 2 x 10(-8 ) g x mL(-1). Based on this, a new method for the determination of nucleic acids is proposed. Synthetic and actual samples are determined satisfactorily. The interaction mechanism is also studied. It is thought that nucleic acid can bind with the Eu(3+)-nicotinic acid complex through electrostatic attraction and thus form a large Eu(3+)-nicotinic acid-nucleic acid complex.

A Pr compound Pr(C3O9H6)·2(H2O) has been synthesized from a hydrothermal reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. The Pr atom is coordinated by nine O atoms. The Pr compound exhibits extensive O-H…O hydrogen-bonding interactions. 2. Experimental All commercially obtained reagent-grade chemicals were used without further purication. A mixture of Pr(NO3)3·6(H2O) (0.1mmol, 0.044g), 2,6-bipyridine dicarboxylic acid (0.1mmol, 0.02g), H3BO3 (0.2mmol, 0.012g) and (NH4)2C2O4 (0.2mmol, 0.028g) were added into 10 mL water with 10%(v/v) ethanol and heated for 9h at 393K. The solution was obtained by filtration after cooling the reaction to room temperature. Colorless single crystals suitable for X-ray measurements were obtained after a few weeks. 3. Results and discussions The title complex crystal structure is shown in Fig.1. The crystal data and structure refinement is shown in Table 1. The Pr atom is coordinated by nine O atoms from three oxalic acid and three water molecular. One oxalic acid molecular bridges two Gd atoms. The Pr-O distances are in the range of 2.470-2.576 A. The angles of O-Pr-O are in the range of 62.8-143.9 ° . Selected bond

A binuclear Zn(II) complex of formula {[Zn(BCPPO)H2O]•3C2H5OH}n (1) [H2BCPPO = Bis 4-carboxyphenyl phenyl phosphine oxide] has been synthesized and structurally characterized by single crystal X-ray diffraction, Powder X-ray diffraction (PXRD), Thermogravimetric analysis (TG), Elemental analysis (EA) and Infrared spectroscopy (IR). As revealed by the single crystal X-ray diffraction, in the binuclear Zn(II) complex, two paddle-wheel-type Zn2 units were connected by four BCPPO ligands to form one-dimensional chains. Their antibacterial activity was evaluated by using a minimal bactericidal concentration (MBC) benchmark. The binuclear Zn(II) complex shows excellent and long-term antibacterial activity against Escherichia coli and Staphylococcus aureus. In addition, the Photoluminescence properties of the binuclear Zn(II) complex was also investigated.

1-Acetyl-3-(4-chlorophenyl)-5-(4-methylphenyl)-2-pyrazoline has been synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. Density functional (DFT) calculations have been carried out for the title compound by using the B3LYP method at the 6-311G** basis set level. The calculated results show that the predicted geometry can reproduce well the structural parameters. Predicted vibrational frequencies have been assigned and compared with experimental IR spectra and they are supported each other. On the basis of vibrational analyses, the thermodynamic properties of the title compound at different temperatures have been calculated, revealing the correlations between C(0)(p, m), S(0)(m), H(0)(m) and temperatures.

Retraction of articles., This article reports the retraction of articles published in Acta Crystallographica Section E between 2005 and 2009.

Four metal–organic coordination polymers, [Cd2(dna)2(2,2′-bpy)2]n (1), {[Cd4(dna)4(im)3]·5H2O}n (2), {[Cd2(dna)2(4,4′-bpy)(H2O)2]·2EtOH}n (3), and {[Cd4(dna)4(1,3-dpp)4(H2O)4]·2H2O}n (4) (H2dna = 4,6-dimethyl-5-nitroisophthalic acid; 2,2′-bpy = 2,2′-bipyridine; im = imidazole; 4,4′-bpy = 4,4′-bipyridine; 1,3-dpp = 1,3-di(4-pyridyl)propane; and EtOH = ethanol, have been solvothermally synthesized and characterized. Compound 1 displays a one-dimensional (1D) ladder structure and the neighbouring ladders are further stabilized by π···π interactions to form a two-dimensional (2D) layer. Compound 2 forms a 2D layer based on infinite 1D [Cd2(COO)4]n chain and the im ligands act as terminal ligands, preventing expansion of the dimensionality. Compound 3 features a 2D 44-sql layer based on binuclear [Cd2(COO)4] secondary building units as 4-connected nodes, and is further linked to be an unusual three-dimensional (3D) supramolecular architecture by hydrogen bonds involving the coordinated water molecules, carboxylate groups, and lattice ethanol molecules. Compound 4 possesses a 2-fold interpenetrated dia net. The diverse structures and topologies of compounds 1–4 indicate that the N-containing ligands have significant effects on the formation of the final network structures. In addition, the thermal stabilities, structure comparison, and photoluminescence properties of the complexes have been investigated.

In the asymmetric unit of the title compound, [Mn(C2O4)(C3H10N2)2]Cl·H2O, there are two independent MnIII complexes, two Cl− anions and two uncoordinated water molecules. Each MnIII atom is hexacoordinated by four N atoms from two propane-1,3-diamine ligands and two O atoms from one oxalate ligand, resulting in a slightly distorted octahedral MnO2N4 geometry. Mn—O and Mn—N bond lengths are in the ranges 1.969 (2)–2.020 (3) and 2.068 (3)–2.113 (4) Å, respectively. There are weak intermolecular O—H...O, O—H...Cl, N—H...O and N—H...Cl hydrogen bonds with D...A distances in the range 2.831 (4)–3.423 (3) Å.