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71.
Peter Brodelius Kjell Nilsson Klaus Mosbach 《Applied biochemistry and biotechnology》1981,6(4):293-307
Whole cells ofTrigonopsis variabilis were immobilized by entrapment in Ca2+-alginate and used for the production of α-keto acids from the corresponding D-amino acids. The D-amino acid oxidase within
the immobilized cells has a broad substrate specificity. Hydrogen peroxide formed in the enzymatic reaction was efficiently
hydrolyzed by manganese oxide co-immobilized with the cells. The amino acid oxidase activity was assayed with a new method
based on reversed-phase HPLC. Oxygen requirements, bead size, concentration of cells in the beads, flow rate, and other factors
were investigated in a “ trickle-bed ” reactor. 相似文献
72.
Tingzhen Li Yong Yang Zhichao Tao Haijun Wan Xia An Chenghua Zhang Hongwei Xiang Yongwang Li 《天然气化学杂志》2007,16(4):354-362
The effect of sulfate on Fischer-Tropsch synthesis performance was investigated in a slurry- phase continuously stirred tank reactor(CSTR)over a Fe-Mn catalyst.The physiochemical properties of the catalyst impregnated with different levels of sulfate were characterized by N_2 physisorption,X-ray photoelectron spectroscopy(XPS),H_2(or CO)temperature-programmed reduction(TPR),Mφssbauer spectroscopy,and CO_2 temperature-programmed desorption(TPD).The characterization results indicated that the impregnated sulfate slightly decreased the BET surface area and pore volume of the catalyst, suppressed the catalyst reduction and carburization in CO and syngas,and decreased the catalyst surface basicity.At the same time,the addition of small amounts of sulfate improved the activities of Fischer- Tropseh synthesis(FTS)and water gas shift(WGS),shifted the product to light hydrocarbons(C_1-C_(11)) and suppressed the formation of heavy products(C_(12 )).Addition of SO_4~(2-)to the catalyst improved the FTS activity at a sulfur loading of 0.05-0.80 g per 100 g Fe,and S-05 catalyst gave the highest CO conversion(62.3%),and beyond this sulfur level the activity of the catalyst decreased. 相似文献
73.
A. T. Soldatenkov K. B. Polyanskii A. V. Temesgen N. D. Sergeeva V. V. Vysotskaya B. B. Averkiev M. Yu. Antipin N. N. Lobanov 《Chemistry of Heterocyclic Compounds》2004,40(5):641-649
New derivatives of piperidino[4,5-d]dioxane and 3-oxa-7-bicyclo[3.3.1]nonane were obtained by the oxidatively catalysed condensation of 4-aryl-1,2,3,6-tetrahydropyridines with formaldehyde. The direction of this reaction is sharply altered in the presence of manganese dioxide to give 6-oxa-2-azabicylo[3.2.1]octan-4-one — the product of the oxidative condensation of a new type. 相似文献
74.
负载锰卟啉催化乙酰胆固醇的选择性环氧化 总被引:1,自引:0,他引:1
多相金属卟啉催化剂已经被用于普通烯烃的环氧化,如表面修饰的多孔分子筛(MCM 41)[1 3],本文制备了高分子负载型锰卟啉用作胆固醇的非对映选择性环氧化催化剂。转化率可达100%,β选择性可达99%。1 实验部分乙酰胆固醇按文献[4]合成。溶剂均为AR级,按文献方法纯化。将Merrifield sPeptideresin(Aldrich,2%,交联度,200-400目,≈2mmolCl/g)加入到精制的DMF中,室温下放置24h,加入5-(对羟基苯基)-10,15,20-三(对甲基苯基)卟啉及无水K2CO3,N2保护下,80℃反应6h,洗涤干燥得到催化剂[1](图1)。催化环氧化反应 将PhIO及催化剂按化学计… 相似文献
75.
催化光度返滴定法测定微量锰的研究 总被引:1,自引:0,他引:1
本文研究了催化光度反滴定法测定微量锰的原理,找到最佳实验条件,确立了实验方法,测定波长622nm;反应时间1min40s;活化剂NTA用量0.60mL,KIO4与孔雀石绿用量比为1.00:0.35,室温下滴定;用pH=5.4的乙酸-乙酸钠缓冲溶液控制溶液酸度;测定Mn^2+的浓度范围为1×10^-7~1×10^-5mol/L,Co^2+,Bi^3+,Ca^2+,Al^3+,Pb^2+,Cu^2+, 相似文献
76.
含N-苯甲酰皮考林酰肼的钒酰、镍及锰配合物的合成和晶体结构 总被引:2,自引:0,他引:2
合成了3个含N-苯甲酰皮考林酰肼(简写为HL)的钒、镍和锰配合物[VO_2L](1,C_(13)H_(10)N_3O_4V,M_r=323.18),[NiL_2]·0.5CH_3OH(2,C_(26.5)H_(22)N_6NiO_(4.5),Mr=555.21)和[MnL_2]·0.5CH_3OH(3,C_(26.5)H_(22)MnN_6O_(4.5),Mr=551.44)。配合物1属三斜晶系,空间群为P1,a=0.71241(3)nm,b=0.89625(6)nm,c=1.11706(6)nm,α=94.715(2)°,β=102.053(2)°,γ=112.375(3)°,V=0.63461(7)nm~3,Z=2,F(000)=328,μ(MoKα)=0.802mm~(-1),R=0.0290,wR=0.0816;配合物2属单斜晶系,空间群为C2/c,a=2.5875(1)nm,b=1.4868(1)nm,c=1.8353(1)nm,β=134.470(4)°,V=5.2081(5)nm~3,Z=8,F(000)=2368,μ(MoKα)=0.795mm~(-1),R=0.0459,wR=0.1330;配合物3属单斜晶系,空间群为C2/c,a=2.60113(3)nm,b=1.45231(4)nm,c=1.92903(1)nm,β=132.824(1)°,V=5.3448(2)nm~3,Z=8,F(000)=2344,μ(MoKα)=0.543mm~(-1),R=0.0457,wR=0.1325。在配合物1中,钒(V)原子具有畸变的N_2O_3四角锥配位构型,晶体内每两个分子通过分子间氢键作用形成缔合分子对。在配合物2和配合物3中,镍(Ⅱ)原子和锰(Ⅱ)原子具有扭曲的N_4O_2八面体配位构型,晶体通过分子间氢键作用形成一维的无限链状结构。红外光谱表明,配体在形成配合物后,ν(C=O)和ν(C=N)红移。电 相似文献
77.
Villanneau R Proust A Robert F Gouzerh P 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(9):1982-1990
The reactions of neutral or cationic manganese carbonyl species towards the oxo-nitrosyl complex [Na(MeOH)[Mo(5)O(13)(OCH(3))(4)(NO)]](2-) have been investigated in various conditions. This system provides an unique opportunity for probing the basic reactions involved in the preparation of solid oxide-supported heterogeneous catalysts, that is, mobility of transition-metal species at the surface and dissolution-precipitation of the support. Under nitrogen and in the dark, the reaction of in situ generated fac-[Mn(CO)(3)](+) species with (nBu(4)N)(2)[Na(MeOH)-[Mo(5)O(13)(OMe)(4)(NO)]] in MeOH yields (nBu(4)N)(2)[Mn(CO)(3)(H(2)O)[Mo(5)O(13)(OMe)(4)(NO)]] at room temperature, while (nBu(4)N)(3)[Na[Mo(5)O(13)(OMe)(4)(NO)](2)[Mn(CO)(3)](2)] is obtained under reflux. The former transforms into the latter under reflux in methanol in the presence of sodium bromide; this involves the migration of the fac-[Mn(CO)(3)](+) moiety from a basal kappa(2)O coordination site to a lateral kappa(3)O site. Oxidation and decarbonylation of manganese carbonyl species as well as degradation of the oxonitrosyl starting material and reaggregation of oxo(methoxo)molybdenum fragments occur in non-deareated MeOH, and both (nBu(4)N)(4)[Mn(H(2)O)(2)[Mo(5)O(16)(OMe)(2)](2)[Mn(CO)(3)](2)] and (nBu(4)N)(4)[Mn(H(2)O)(2)[Mo(5)O(13)(OMe)(4)(NO)](2)] as well as (nBu(4)N)(2)[MnBr[Mo(5)O(13)(OMe)(4)(NO)]] have been obtained in this way. The rhenium analogue (nBu(4)N)(2)[Re(CO)(3)(H(2)O)[Mo(5)O(13)(OMe)(4)(NO)]] has also been synthesized. The crystal structures of (nBu(4)N)(2)[Re(CO)(3)(H(2)O)[Mo(5)O(13)(OMe)(4)(NO)]], (nBu(4)N)(3)[Na[Mo(5)O(13)(OMe)(4)(NO)](2)[Mn(CO)(3)](2)], (nBu(4)N)(4)[Mn(H(2)O)(2)[Mo(5)O(16)(OMe)(2)](2)[Mn(CO)(3)](2)], (nBu(4)N)(4)[Mn(H(2)O)(2)[Mo(5)O(13)(OMe)(4)(NO)](2)] and (nBu(4)N)(2)[MnBr[Mo(5)O(13)(OMe)(4)(NO)]] have been determined. 相似文献
78.
Hanhua Zhao Curtis P. Berlinguette John Bacsa Shane E. Tichy Kim R. Dunbar 《Journal of Cluster Science》2003,14(3):235-252
The preparation and characterization of two new mixed-valence, trinuclear species, [Mn3O(O2CCF3)6(H2O)3]CF3COOH4/3H2O (1) and [Mn3O(O2CCF3)6(CH3COOH)3] (2), is reported. Compound 1 crystallizes in the triclinic space group, P¯1 (No. 2), with the parameters, a=12.3131(9) Å, b=12.4427(9) Å, c=12.965(1) Å, =72.593(4)°, =73.453(5)°, =68.345(4)°, V=1727.2(2) Å3, and Z=2. A total of 14060 reflections were collected in the range 1.6827.52°. The final weighted and non-weighted agreement indices, R1=0.0589 and wR2=0.1445 were based on a total of 6953 unique reflections with an R
int value of 0.0542. Compound 2 crystallizes in the monoclinic space group, P21/n (No. 14), with the parameters, a=12.876(3) Å, b=12.212(4) Å, c=17.732(4) Å, =100.40(3)°, V=3640.4(1) Å3, and Z=4. A total of 32197 reflections were collected in the range 1.7227.13°. The final weighted and non-weighted agreement factors, R1=0.0647 and wR2=0.1609 were based on a total of 8018 unique reflections with an R
int
value of 0.0462. An investigation of the physical properties revealed that both compounds display an intermediate ground state of S=3/2 as a consequence of intramolecular antiferromagnetic coupling. The magnetic data for compound 1 was best fit to the parameters g=2.09, J=–5.5 cm–1, J=–3.4 cm–1, and D
Mn(III)=–4.5 cm–1; the data for compound 2 was best fit to the parameters g=2.10, J=–2.9 cm–1, J=–5.5 cm–1, and D
Mn(III)=–4.5 cm–1. 相似文献
79.
合成了一个新配合物[Mn(napn)(CH3OH)2]ClO4 (C26H26 Cl N2O8Mn,Mr = 584.88,H2napn = 双a-萘酚醛缩乙二胺),并测定了其晶体结构。晶体属于三斜晶系,空间群P ,a = 7.813(1),b = 13.025(2),c = 14.089(2) ? = 64.89(3), = 83.98(3), = 78.11(3)海琕 = 1270.16 ?,Z = 2, Dc = 1.529 g/cm3, F(000) = 604, R = 0.0837, wR = 0.1636。锰(Ⅲ)离子的配位构型为拉长的八面体。Schiff碱配体napn2-中的N2O2在赤道平面与锰(Ⅲ)形成四配位,2个CH3OH中的O原子分别在赤道平面两侧轴向位置与锰(Ⅲ)配位。由于Jahn-Teller效应,轴向上的MnO平均键长为2.52 拧A硗猓О写嬖诜肿幽诤头肿蛹淝饧? 相似文献
80.
1INTRODUCTIONRecently,considerableattentionhasbeenpaidtotheinvestigationofcoordinationchemistryofmanganeseindifferentoxidationstatesnotonlybecauseofthediscoveryoftightlyboundmanganeseatomsinvariousbiomolecules[libutalsobecauseoftheirinterestingstructural,magneticandspectroscopicfeatures.Wehavepreparedseveralcomplexesofmanganese(n)withdifferentligands.Thestructuresandfeaturesofthesecompoundsarestudiedsystematically.Inthispaperwedescribethestructureofthecomplexwiththeligandsofphenanthroline… 相似文献