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To learn the spatial and temporal distribution of Bt proteins in Bt maize leaves, Bt protein levels of Bt maize leaves and their corresponding non-transgenic lines were detected and analysed by the ELISA method. The results showed that Bt proteins were expressed in the leaves of Bt maize varieties during all periods of their growth, while no such Bt proteins were detected in the leaves of non-transgenic maize varieties. The range of leaf Bt proteins was 1.08∼5.81 µg.g−1 FW, which could effectively protect Bt maizes from the corn borer pest during their growth periods. Furthermore, the younger leaves of Bt maizes had significantly lower levels of Bt proteins than their older leaves. In most periods, Bt protein content of Bt maize leaves under drought stress was lower than that under normal growth conditions, but Bt protein content under nutrition stress was higher than that under normal growth conditions. The results provided a full pattern of the spatial and temporal distribution of Bt proteins in Bt maize leaves.

Three new organic–inorganic hybrid compounds (2-C{sub 5}H{sub 7}N{sub 2}){sub 3}·(SiMo{sub 12}O{sub 40})·(C{sub 4}H{sub 8}N{sub 4}){sub 0.5}·(C{sub 5}H{sub 6}N{sub 2}){sub 2}·(H{sub 2}O){sub 2} (1), (3-C{sub 5}H{sub 7}N{sub 2}){sub 8}·(SiMo{sub 12}O{sub 40}){sub 2}·(C{sub 5}H{sub 7}N{sub 3}){sub 2}·(H{sub 8}O{sub 4})·(H{sub 2}O){sub 8} (2) and (4-C{sub 5}H{sub 7}N{sub 2}){sub 6}·(SiMo{sub 12}O{sub 40}) (3) composed the heteropolymolybdate α-H{sub 4}SiMo{sub 12}O{sub 40} and the organic substrate 2/3/4-aminopyridine have been hydrothermally synthesized and characterized by routine methods. Compounds 1 and 2 exhibit a three-dimensional supramolecular network via hydrogen bond and π–π stacking interactions. Compound 2 contains a tetramolecular water cluster which consists of four water molecules connected by hydrogen bonds. These compounds exhibit good thermal stability and photoluminescent phenomena. Compounds 1 and 3 are active for catalytic oxidation of methanol in a continuous-flow fixed-bed micro-reactor, when the initial concentration of methanol is 2.75 g m{sup −3} in air and flow rate is 10 mL min{sup −1} at 150 °C, corresponding to the elimination rate of methanol i.e. 87.7% and 76.8%, respectively. - Three new Keggin type inorganic–organic hybrid frameworks were synthesized. Compounds exhibit an extended three-dimensional supramolecular network. Compounds 1 and 3 have better catalytic activity for eliminating methanol. Highlights: ► Three 3-D Keggin inorganic–organic hybrid frameworksmore » were synthesized. ► The π–π stacking interactions are existed in Compounds 1 and 2. ► Compound 2 contains a tetramolecular water cluster connected by hydrogen bond. ► Compounds 1 and 3 are active in the catalytic oxidation of methanol into CO{sub 2} and H{sub 2}O.« less

Mesoporous TiO 2 doped with different amounts of Sm were prepared via a sol-gel route with Pluronic P123 as template. The materials were characterized by X-ray diffraction, transmission electron microscopy, and N 2 sorption experiments, etc. The photocatalytic activity of the mesoporous TiO 2 was tested in elimination of gaseous methanol and acetone. The Sm doped mesoporous TiO 2 have higher activity than those of the commercial photocatalyst (Degussa, P25) and Sm doped TiO 2 counterparts without mesopore structure under ultraviolet light irradiation. A possible mechanism was proposed to account for the high photocatalytic activity of the Sm doped mesoporous TiO 2 . The superior activity of the Sm doped mesoporous TiO 2 may be attributed to the synergic effect of the high surface area, mesopore structure and doped Sm species.

Three new organic–inorganic supramolecular hybrids, namely, (2-C5H7N2)4(PMo12O40)2·(2-C5H6N2)6·(C4H8N4)·H2O (compound 1), (3-C5H7N2)6·(PMo12O40)2·(3-C5H6N2)4·H8O4·(H2O)8 (compound 2), (4-C5H7N2)6(PMo12O40)2·(4-C5H6N2)4·(C4H6N3) (compound 3), have been synthesized by hydrothermal method and characterized by elemental analyses, IR, UV–vis, TGA and single-crystal X-ray diffraction. Compound 1–3 constructed from Keggin polyoxoanions and 2-/3-/4-aminopyridine organic ligands, exhibit an extended three-dimensional supramolecular network via hydrogen bonding and π–π stacking interactions, while compound 2 contains a tetramolecular water clusters. compounds 1 and 3 have a higher catalytic activity for the oxidation of acetone tested in a continuous-flow fixed-bed micro-reactor. When the initial concentration of the acetone is 6.1 g m−3 in air and the flow velocity is 4.5 mL min−1, the acetone is completely eliminated at 160 °C. But compound 2 has lower catalytic activity for the oxidation of acetone.

Mesoporous anatase doped with various amounts of Eu were synthesized via a sol-gel route using Pluronic P123 as template. The XRD and TEM results show that Eu doping favors the formation of anatase with smaller crystal size. The photocatalytic activity of the mesoporous anatase was tested in photocatalytic elimination of gaseous methanol. The photocatalysts exhibited higher activity than that of the commercial photocatalyst (Degussa, P25) under either ultraviolet or visible light irradiation. The superior activity of the mesoporous anatase may be attributed to the synergic effects of the surface area, crystal size and doped Eu species.

(C5H7N2)3(AsMo12O40)・2C5H6N2・1.5H2O was hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Crystal data: monoclinic, P21/n, a = 13.310(3), b = 22.399(5), c = 19.820(4) A° , β = 99.99(3) ◦, V = 5819(2) °A3, Z = 1, wR(F2) = 0.1345. The structure consists of Keggin-type [AsMo12O40]3− polyoxoanions. The title compound has a high catalytic activity for the oxidation of acetone tested in a continuous-flow fixed-bed micro-reactor. When the initial concentration is 5.3 g m−3 in air and the flow rate is 2.5 mL min−1, the acetone is completely eliminated at 150 ◦C.

Au/γ-Al2O3 catalysts were prepared by deposition-precipitation method for the catalytic combustion of low concentration alcohol streams (methanol, ethanol, iso-propanol and n-propanol). The catalysts were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffractometry (XRD) and energy dispersive X-ray micro analysis (EDS) techniques. The XPS results showed that there was only Au0 on the surface of catalysts. The XRD patterns showed that Au was presumably highly dispersed over γ-Al2O3. The temperatures for complete conversion of methanol, ethanol, iso-propanol and n-propanol with concentration of 2.0 g/m3 were 60, 155, 170 and 137 ?, respectively, but they were completely mineralized into CO2 and H2O at 60, 220, 260 and 217 ? respectively over the optimized catalyst. The activity of the catalyst was stable in 130 h. The kinetics for the catalytic methanol elimination followed quasi-first order reaction expressed as r=0.652 8c0+0.084 2. The value of apparent activation energy is 54.7 kJ/mol in the range of reaction temperature.

The binary composite photo-catalysts CeO2/TiO2, ZrO2/TiO2 and the ternary composite photo-catalysts H3PW12O40-CeO2/TiO2, H3PW12O40-ZrO2/TiO2 were prepared by sol-gel method. The catalysts were characterized by thermogravimetric-differential thermal analysis (TG-DTA), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The photocatalytic elimination of methanol was used as model reaction to evaluate the photocatalytic activity of the composite catalysts under ultraviolet light irradiation. The effects of doped content, activation temperature, time, initial concentration of methanol and gas flow rate on the catalytic activity were investigated. The results showed that after doping a certain amount of CeO2 and ZrO2, crystallization process of TiO2 was restrained, particles of catalysts are smaller and more uniform. Doping ZrO2 not only significantly improved the catalytic activity, but also increased thermal stability. Doping H3PW12O40 also enhanced the catalytic activity. The catalytic activities of binary and ternary composite photocatalysts were significantly higher than un-doped TiO2. The dynamics law of photocatalytic reaction over the binary CeO2/TiO2 and ZrO2/TiO2 catalysts has been studied. The activation energy 15.627 and 15.631 kJ/mol and pre-exponential factors 0.5176 and 0.9899 s(-1) over each corresponding catalyst were obtained. This reaction accords to the first order dynamics law.

Two new complexes, [Co2(CH2=C(CH3)CO2)4(phen)2(H2O)2] (1) and [Pb2(CH2=C(CH3)CO2)4(phen)2] (phen = 1,10-phenanthroline) (2), have been synthesized and structurally characterized by single crystal X-ray diffraction methods. There are two cocrystallized conformers of [Co(CH2=C(CH3)CO2)2(phen)(H2O)] in the asymmetric unit of 1 with the Co atoms displaying similar coordination modes. In the asymmetric unit of 2, there exist two crystallographically independent [Pb(CH2=C(CH3)CO2)2(phen)] molecules with the Pb atoms showing completely different coordination geometries. Weak intermolecular interactions such as hydrogen bonding and π–π stacking are responsible for the supramolecular assembly and stabilization of the crystal structures of 1 and 2. The complexes are characterized by elemental analysis, IR spectra, and UV–Vis spectra. The fluorescent properties of 2 are also discussed.

A new binuclear complex, [Cd(ClCH2CH2CO2)2(phen)]2 (1), has been synthesized and structurally characterized by single crystal X-ray diffraction methods. The Cd atoms are linked by carboxylate oxygen atoms into a four-membered Cd2O2 rhombic ring with a Cd···Cd separation of 3.824 Å . Two carboxylate groups act as bidentate, and two as both bidentate bridging and bidentate chelating ligands. The hydrogen bonding and π-π stacking interactions are responsible for the supramolecular assembly and stabilization of the crystal structure. The complex has been characterized by elemental analysis, IR and UV/Vis spectra, and thermogravimetric and differential thermal analysis (TG/DTA). The complex exhibits blue fluorescence in the solid at room temperature.

Photocatalysts M3PW12O40 (M = NH4+, Cs+, Ag+, Cu2+) were prepared by microwave radiation solid-phase synthesis method. The results from SEM and XRD characterization reveal that the average particle size of M3PW12O40 is 15–80 nm. Diffuse reflectance UV–vis spectra of M3PW12O40 shows that the absorption band shifted from 260 to 270–350 nm and become broad in comparison with those of H3PW12O40. The results of photocatalytic degradation of formaldehyde prove that the shift of UV–vis absorption band is proportionally related to the activity of the catalyst. The Cu3(PW12O40)2 catalyst which has the maximal red shift to 350 nm of its UV–vis absorption band is found to be the most efficient catalyst. When the concentration of formaldehyde is 32.79 mg m−3, the conversion of the formaldehyde is basically completed under the flow rate of 40 ml min−1 over 0.1 g M3PW12O40 catalyst. The M3PW12O40 catalysts prepared by this method are stable and the regeneration of the catalysts is easy. The catalysts have promising applications in the photocatalytic degradation of organic contamination.

The NdPW12O40/TiO2 composite catalyst was prepared by the sol-gel method and characterized by thermogravimetric-differential thermal analysis, infrared spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy, fluorescence emission spectroscopy, scanning electron microscopy, and X-ray diffraction. The photocatalytic eliminations of acetone and methanol were used as model reactions to evaluate the photocatalytic activity of the composite catalyst under ultraviolet light irradiation. The results show that TiO2 modified by NdPW12O40 has small crystal size (11 to 14 nm) and large surface area, and the aggregation of TiO2 particles is effectively inhibited. When the initial concentration of acetone is 6.58 g/m3 and the space time is 2.4 s, the mineralization rate is 96.74% using 0.1 g of 1% NdPW12O40/TiO2 as the catalyst, which conforms to the requirements of emission standards for air pollutants. Methanol can be mineralized completely when its initial concentration is 8.82 g/m3 and the space time is 2.0 s. Compared with pure TiO2, the light absorption ability of NdPW12O40/TiO2 gets enhanced, and the absorption region extends to long wavelengths by 20 nm.

Keggin-type molybdophosphoric heteropolyacid catalysts with iron cation partially substituted for proton and arsenic for phosphorus in a bulk form have been synthesized for the selective oxidation of isobutane into methacrylic acid (MAA). It was found that the addition of iron can obviously improve both the conversion of isobutane and selectivity to MAA, while arsenic substitution was mainly in favor of the selectivity to MAA. The best conversion and yield of MAA were 23.9% and 16.7%, respectively, which was obtained at 370 °C with a space velocity of 420 h −1 over H x Fe 0.12 PVAs 0.3 Mo 11 O y heteropoly compound catalyst. The catalysts were characterized by XRD, SEM, FT-IR, and TPR.

Single-crystal XRD reveals a monoclinic structure for (II) (space group P21/c, Z = 4), a tetragonal structure for (III) (space group P42/n, Z = 2), and a trigonal structure for (IV) (space group R3, Z = 3).

Novel composite photocatalysts, Ag@(Ag2S/Ag3PO4), have been synthesized by controlled calcination and exhibited much higher activity than that of Ag3PO4, Ag2S/Ag3PO4, Ag/Ag3PO4 and AgX/Ag3PO4 (X = Cl, Br and I) in degradation of rhodamine B. The excellent activity is ascribed to the synergistic effect between Ag and Ag2S.