百菌清及其三氟衍生物对番茄早疫病菌的室内抑菌活性比较

采用生长速率法测定了不同浓度的百菌清及其三氟衍生物对番茄早疫病菌Alternaria solani(Ell,et Mart.)Jones es Gmut的室内杀菌毒力。试验结果表明，百菌清及其三氟衍生物的ED50值分别为6089．89mg／L和156．43mg/L。，前者是后者的38．93倍。百菌清三氟衍生物的毒力明显高于百菌清。     

The influence of Glu44 and Glu56 of cytochrome b5 on the protein structure and interaction with cytochrome c

The gene encoding trypsin-solubilized bovine liver microsomalcytochrome b₅ (82 residues in length) has been mutated, in whichthe codons of Glu44 and Glu56 were changed to those of Ala.The mutated genes were expressed in Escherichia coli successfullyand three mutant proteins (E44A, E56A and E44/56A) were obtained.The UV-visible, CD and ¹H NMR spectra of proteins have beenstudied. The results show that the mutagenesis at surface residuesdoes not alter the secondary and tertiary structures of cytochromeb₅ significantly. The interactions between recombinant cytochromeb₅ and its mutants with cytochrome c were studied by using opticaldifference spectra. The results demonstrated that both Glu44and Glu56 of cytochrome b₅ participate in the formation of acomplex between cytochrome b₅ and cytochrome c.     

5—烃基—2,3—二甲基吡嗪的合成

2,3-二基-5,6-二氢吡嗪与醛或酮在氢氧化钠的乙醇溶液中反应制得16种5-烃基-2,3-二甲基吡嗪。产率66%～90%。其中6种为新合成的化合物。产率17%～87.9%。     

Electrosyntheses and characterization of poly(5‐bromoindole) in boron trifluoride diethyl etherate

Poly(5‐bromoindole) (PBrI) films were synthesized electrochemically by direct oxidation of 5‐bromoindole in pure boron trifluoride diethyl etherate. The oxidation potential of 5‐bromoindole in this medium was measured to be only 0.97 V vs. saturated calomel electrode, which was lower than that determined in acetonitrile + 0.1 mol L^?1 Bu₄NBF₄ (1.08 V). PBrI films obtained from this medium showed good electrochemical behavior and good thermal stability. Structural studies showed that the polymerization of 5‐bromoindole ring occurred at 2,3 position. As‐formed PBrI films were thoroughly soluble in strong polar solvent dimethylsulfoxide and partly soluble in tetrahydrofuran. Fluorescent spectral studies indicated that PBrI was a good blue‐light emitter. The excitation and emission spectra of PBrI showed a significant shift to longer wavelength compared with that of the monomer, consistent with the greater extent of electron delocalization. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 539–547, 2006     

Isobutane/2-butene alkylation on MCM-22 catalyst. Influence of zeolite structure and acidity on activity and selectivity

The catalytic behavior of the novel MCM-22 zeolite for the continuous alkylation of isobutane with 2-butene has been investigated at a temperature of 50°C, 2.5 MPa total pressure, and a variety of olefin space velocities. At high olefin conversions the MCM-22 zeolite showed a very high initial cracking activity attributable to strong Brønsted acid sites, as well as to the existence of strong diffusional restrictions of the TMP's (formed inside the zeolite) to exit through the channels. At short times on stream (TOS), TMP's account for ca. 40% of the C₈ fraction. The olefin conversion and the cracking activity rapidly decline with TOS, while the alkylate product became richer in dimethylhexenes, indicating a predominance of 2-butene dimerization and a loss of hydrogen transfer activity as the catalyst aged. Moreover, MCM-22 gives less TMP's than large-pore zeolites (USY, beta, mordenite), but more than the mediumpore ZSM-5 at similar 2-butene conversion. The latter catalyst was much more selective for olefin dimerization than for isobutane alkylation, presumably because formation of the bulkier TMP's was strongly impeded in its smaller pores.     

Chemisorption of alkenes on copper-exchanged ZSM-5 zeolite

On Cu-ZSM-5 zeolite at room temperature, propane is physisorbed, while propene shows characteristics of chemisorption. The chemisorption mode has certain advantages for the catalytic control of automotive emissions. Alkane and alkene adsorption equilibria and kinetics are compared on Cu-ZSM-5 and on ZSM-5 free of alumina. The results are discussed in terms of the Langmuir adsorption isotherm.     

Surface properties of ZSM-5 modified by phosphorus

Phosphorus modification of ZSM-5 leads to extra framework P⁵⁺ and probably incorporation of +3 valence state of P in the framework. The resulting system has increased Brønsted acidity. Theoretical calculations also favour the postulate that phosphorus in +3 valence state can be incorporated into the lattice.     

Benzene Alkylation with Propane over Mo Modified HZSM-5

Benzene alkylation with propane has been studied over HZSM-5 loading 3.1–15.4 wt% Mo in continuous-flow microreactor under 350 °C and atmospheric pressure with the highest activity obtained at 6.7 wt% Mo loading. C_7–9 aromatics were obtained as main products while the total amount of benzene rings kept unchanged. i-Propylbenzene and n-propylbenzene are formed primarily, while toluene, ethylbenzene, and ethyl-toluene are formed secondly from the propylbenzenes. Catalytic performance of 6.7 wt% Mo/HZSM-5(38) partially poisoned by NH₃ shows that the strong acid sites play a crucial role in the alkylation. Low SiO₂/Al₂O₃ ratio of HZSM-5 in the Mo modified catalysts gives high propane conversion. Two hydrothermal treatment methods were applied to the 6.7 wt% Mo/HZSM-5(38) catalyst, caused decrease of propane conversion but result in different product distribution. A possible reaction mechanism concerning bifunctional active centers resulted from combination of loaded Mo species and strong acid centers on HZSM-5 is proposed.     

焙烧法水热合成5A沸石分子筛

焙烧活化化工原料氢氧化钙、氢氧化钠、硅酸钠和二氧化硅，探索焙烧法水热合成5A沸石分子筛的条件。并通过X射线粉末衍射(XPS)和扫描电镜(SEM)对产品进行表征。焙烧原料合成5A沸石分子筛的优化条件为焙烧温度550 ℃, 焙烧时间4 h, 晶化时间4 h。     

2，6－双（5－硝基－2－糠叉）环己酮的制备

用５－硝基糠叉二醋酸酯与环己酮在６０％Ｈ３ＰＯ４溶液中缩合制得标题物。反应混合物在１００℃下搅拌反应５ｈ得６１％的２，６－双（５－硝基－２－糠叉）环己酮。分别经ＩＲ、１ＨＮＭＲ、ＭＳ、ＵＶ、ＴＬＣ和元素分析进行了表征和鉴定。