黑龙江嫩江地区三矿沟矽卡岩型铜-铁-钼多金属矿床的成矿流体特征与成矿机制

三矿沟铜-铁-钼多金属矿床是大兴安岭地区三矿沟-多宝山构造-成矿带中一个比较典型的矽卡岩型矿床。对干矽卡岩阶段（Ⅰ）的石榴子石、湿矽卡岩-氧化物阶段（Ⅱ）的石英、早期硫化物阶段（Ⅲ）的石英和晚期硫化物阶段（Ⅳ）的方解石中的流体包裹体进行了岩相学观察和显微测温研究。研究结果表明,成矿各阶段热液矿物中的原生流体包裹体类型丰富,主要为气液两相包裹体,其次为纯气相包裹体,偶见纯液相包裹体。石英中也有大量含NaCl子矿物的多相包裹体,其均一温度变化于152~478℃之间,盐度为1.57~58.02wt%NaCl,密度变化范围为0.64~1.18g/cm3,总体属中—高温度、中—高盐度、中等密度的体系;据此计算的成矿压力范围为39.44~133.65MPa,成矿深度介于3.94~9.64km之间,表明该矿床形成于中深成环境。

拉拉铁氧化物铜金钼稀土矿床Re-Os同位素年龄及其地质意义

拉拉铁氧化物 铜 金 钼 稀土矿床的成矿年龄一直悬而未决。文章采用辉钼矿Re Os同位素方法,首次对该矿床的形成年龄进行了直接测定。4个样品的测定结果为:928(±1)1005(±1)Ma。这一结果与矿床的地质事实相吻合,因此它代表了拉拉矿床的成矿时代。根据这一年龄数据与赋矿围岩河口群的变质年龄相一致等证据,初步提出拉拉矿床为变质热液成因。此外拉拉矿床的矿化时代与Rodinia泛大陆拼贴的时限相当,这表明Rodinia泛大陆拼贴事件对扬子地块的成矿作用产生了深刻的影响。

铁钼催化剂上甲醇氧化制甲醛宏观动力学的研究

采用磁力驱动内循环无梯度反应器测试由西南化工研究院研制的一种国产甲醇氧化制甲醛催化剂的宏观动力学数据 ,并建立了宏观反应动力学模型。该动力学模型分为含水模型和非含水模型 ,其中含水模型比非含水模型具有更好的适应性。圆整后的含水模型可用下式表示 :甲醇反应速率 :r′11=2 70× 10 5exp(- 4 88× 10 4 /RT) y0 9M y1 3 O y-0 15W一氧化碳生成速率 :r′2 2 =3 40× 10 4 exp(- 5 6 7× 10 4 /RT) y1 2F y1 2O y-0

溶胶-凝胶法制备Fe_2(MoO_4)_3超微粒子催化剂

以硝酸铁和钼酸铵为原料 ,采用溶胶 -凝胶法和微波加热技术制备了 Fe2 ( Mo O4) 3超微粒子催化剂 ,使用DTA-TG,IR,XRD以及 BET比表面测试等手段 ,考察了制备条件对复合氧化物超微粒子形成、晶相和比表面积的影响。同时测试了该样品对甲苯选择性氧化制苯甲醛的催化性能。结果表明 :制备 Fe2 ( Mo O4) 3超微粒子的适宜条件为 :初始溶液 p H=1 .0 ,mol柠檬酸 ∶ mol(铁 +钼 ) =0 .4。在此条件下制得的干凝胶 ,经微波加热处理后粒子的比表面积为 36.4 m2 /g,粒径约为 35 nm。

固氮酶Fe-Mo辅因子空间构型模拟——分子力学在分子模型设计中的应用

在分子模型设计中交替使用分子图形学软件和分子力学优化计算,用计算机模拟固氮酶Fe-Mo辅因子空间构型,从而为进一步的理论研究提供了一个非实验方法的有效手段。

两种线型Mo-Fe-S原子簇元件化合物阴离子的简正坐标分析

本文报导了[S_2MoS_2FeCl_2]^(2-)(简记为K_1)和[S_2MoS_2Fe(SPh)_2]^(2-)(简记为K_1′)两种簇阴离子的简正坐标分析的结果。振动基频的计算值与观测值符合良好,两者平均偏差都小于1.25%,证实了振动谱带的归属;确定了相应的力常数。最后讨论了所得结果的合理性和可靠性。

Conversion and reaction kinetics of coke oven gas over a commercial Fe-Mo/Al_2O_3 catalyst

Producing methanol from coke oven gas(COG) is one of the important applications of COG. Removal of sulfur from COG is a key step of this process. Conversion and reaction kinetics over a commercial Fe-Mo/Al2O3 catalyst(T-202) were studied in a continuous flow fixed bed reactor under pressures of 1.6-2.8 MPa, space time of 1.32-3.55 s and temperatures of 240-360 °C. Though the COG contains about 0.6 mol/mol H2, hydrogenation of CO and CO2 is not significant on this catalyst. The conversions of unsaturated hydrocarbons depend on their molecular structures. Diolefins and alkynes can be completely hydrogenated even at relatively low temperature and pressure. Olefins, in contrast, can only be progressively hydrogenated with increasing temperature and pressure. The hydrodesulfurization(HDS) of CS2 on this catalyst is easy. Complete conversion of CS2 was observed in the whole range of the conditions used in this work. The original COS in the COG can also be easily converted to a low level. However, its complete HDS is difficult due to the relatively high concentration of CO in the COG and due to the limitation of thermodynamics. H2 S can react with unsaturated hydrocarbons to form ethyl mercaptan and thiophene, which are then progressively hydrodesulfurized with increasing temperature and pressure. Based on the experimental observations, reaction kinetic models for the conversion of ethylene and sulfur-containing compounds were proposed; the values of the parameters in the models were obtained by regression of the experimental data.

Removal of tungsten from molybdate solution by Fe-Mn binary oxide adsorbent

Considering the different geochemical enrichment behaviors of W and Mo,Fe?Mn binary oxide(FMBO),ferric hydroxide(Fe(OH)3)and manganese dioxide(MnO2)were studied to separate W from molybdate solution,respectively.The experimental results demonstrated that Fe?Mn binary oxide(FMBO)was the most suitable adsorbent for the separation.Under a wide pH(6.9?11.3)region,more than80%W removal efficiency and less than3%Mo loss could be obtained.In addition,the Fe?Mn binary oxide adsorbent can be regenerated by treating with3mol/L NaOH,and the W adsorption efficiency was retained after five adsorption?desorption?regeneration cycles.All these indicate that the Fe?Mn binary oxides have the potential for the separation of W from molybdate solution.

Preparation and Crystal Structure of Hetero-metal Clusters [η~5-C_5H_4C(O)CH_2CH_2C(O)OCH_3]FeCoM(μ_3-S)(CO)_8 (M = Mo or W)

The hetero-metal clusters [■5-C5H4C（O）CH2CH2C（O）OCH3]FeCoM（■3-S）（CO）8 （M = Mo 1, M = W 2） were prepared by thermal reactions of FeCo2（CO）9(（3-S） with metal exchange reagent [■5-C5H4C（O）CH2CH2C（O）OCH3]M（CO）3Na （M = Mo or W） in THF. Cluster 1 reacted with 2,4-dinitrophenylhydrazine at room temperature to yield the cluster hydrazone derivative (（3-S）CoFeMo（CO）8[(5-C5H4C（NR）Me] [R = NHC6H3-2,4-（NO2）2] 3. All the compounds were characterized by elemental analyses, IR and NMR spectra. Cluster 1 was determined by single crystal X-ray diffraction. Crystal data: C18H11O11SCoFeMo, Mr = 646.05, triclinic, space group P, a = 8.148（2）, b = 10.685（3）, c = 13.410（4） ?, ( = 100.077（5）, ( = 102.452（5）, ( = 91.108（6）(, V = 1120.4（5） ?3, Z = 2, Dc = 1.915 g/cm3, F（000） = 636, ( = 2.071 mm(1, the final R = 0.0378 and wR = 0.0968 for 5074 observations with (I > 2（（I））.

A Novel γ-Alumina Supported Fe-Mo Bimetallic Catalyst for Reverse Water Gas Shift Reaction

In reverse water gas shift （RWGS） reaction COa is converted to CO which in turn can be used to pro- duce beneficial chemicals such as methanol. In the present study, Mo/AlaO3, Fe/AlaO3 and Fe-Mo/Al2O3 catalysts were synthesised using impregnation method. The structures of catalysts were studied using X-ray diffraction （XRD）, Brunauer-Emmett-Teller （BET） method, inductively coupled plasma atomic emission spectrometer （ICP-AES）, temperature programmed reduction （H2-TPR）, CO chemisorption, energy dispersive X-ray （EDX） and scanning electron microscopy （SEM） techniques. Kinetic properties of all catalysts were investigated in a batch re- actor for RWGS reaction. The results indicated that Mo existence in structure of Fe-Mo/AlzO3 catalyst enhances its activity as compared to Fe/AlaO3. This enhancement is probably due to better Fe dispersion and smaller particle size of Fe species. Stability test of Fe-Mo/AlzO3 catalyst was carried out in a fixed bed reactor and a high CO yield for 60 h of time on stream was demonstrated. Fez（MoO4）3 phase was found in the structures of fresh and used catalysts. TPR results also indicate that Fez（MoO4）3 phase has low reducibility, therefore the Fe2（MoO4）3 phase significantly inhibits the reduction of the remaining Fe oxides in the catalyst, resulted in high stability of Fe-Mo/Al2O3 catalyst. Overall, this study introduces Fe-Mo/Al2O3 as a novel catalyst with high CO yield, almost no by-products and fairly stable for RWGS reaction.

Synthesis and Structural Characterization of [(h^5-C_5Me_5)_2Mo_2Fe_2S_4Br_2]

The reactions of [(h5-C5Me5)Mo(StBu)3] with equimolar FeBr3 in THF afforded a neutral tetranuclear cluster [(h5-C5Me5)2Mo2Fe2S4Br2] 1. The structure of 1 was determined by single-crystal X-ray diffraction analysis. 1 crystallizes in the monoclinic space group P21/n (No. 14) with a = 9.691(2), b = 15.204(2), c = 18.850(2) ? b = 96.44(1), V = 2759.8(7) ?, Z = 4, Mr = 862.08, Dc = 2.075 g/cm3, F(000) = 1680, m (MoKa) = 51.31 cm-1 and T = 296.2 K. With the use of 3667 observed reflections (I > 3.0s(I)), the structure was refined to R = 0.041 and Rw = 0.051. 1 is composed of a distorted Mo2Fe2S4 cubane core with two Br atoms and two h5-C5Me5 groups coordinating at the Fe and Mo sites, respectively. The lengths of MoMo and FeFe bonds are 2.826 and 2.773 ? respectively the mean length of MoFe bond is 2.751 ?

Methanol oxidation over shell-core MOx/Fe2O3（M = Mo, V, Nb） catalysts

We present a comparison of Mo, V and Nb oxides as shell materials atop haematite cores used for selective methanol oxidation. While Mo and V both yield high selectivity to formaldehyde, Nb does not. Very different reactivity patterns are seen for Nb, which mainly shows dehydrogenation (to CO) and dehydration (to DME), indicating the lack of a complete shell, while Raman spectroscopy shows that the Mo and V formation process is not followed by NbOx. We suggest this is due to the large differences in mobility within the solid materials during formation, NbOx requiring significantly higher (and deleterious) calcination temperatures to allow sufficient mobility for shell completion.

Study on Infrared Spectra and Chemical Bonding of the Cluster Anion[Cl_2FeS_2MoS_2Cu(PPh_3)_2]￣-

The Fourier transform infrared spectra of the cluster anion[Cl2Fe2S2MoS2Cu(PPh3)2]- are measured between 550 and 90 cm(-1).The empirical assignments have been made for the vibration bands of main valence bonds.In order to verify the assignments of the bands and obtain the force constants the approximate normal coordinate analysis for the title anion has been carried out.It is found that the calculated frequencies are in good agreement with the observed ones.While Quantum-Chemical calculation is used to elucidate the chemical bonding characteristics for the title anion.

Performance Comparison of Two Newly Developed Bimetallic(X-Mo/Al2O3, X=Fe or Co) Catalysts for Reverse Water Gas Shift Reaction

The performance of the two newly developed bimetallic catalysts based on the precursor, Mo/Al_2O_3, was compared for reverse water gas shift(RWGS) reaction. The structures of the precursor and the catalysts were studied using X-ray diffraction(XRD), Brunauer–Emmett–Teller(BET) analysis, inductively coupled plasma-atomic emission spectrometry(ICP-AES), CO chemisorption, temperature programmed reduction of hydrogen(H_2-TPR) and scanning electron microscopy(SEM) techniques. The activity of Fe-Mo and Co-Mo catalysts was compared in a fixed bed reactor at different temperatures. It is shown that the Co-Mo catalyst has higher CO_2 conversion at all temperature level. The time-on-stream(TOS) analysis of the activity of catalysts for the RWGS reaction was carried out over a continuous period of 60h for both catalysts. The Fe-Mo/Al_2O_3 catalyst exhibits good stability within a period of 60h, however, the Co-Mo/Al_2O_3 is gradually deactivated after 50h of reaction time. Existence of(Fe_2(MoO4_))_3 phase in Fe-Mo/Al_2O_3 catalyst makes this catalyst more stable for RWGS reaction.

Synthesis and Structure of Paramagnetic β-OctamolybdateComplex, [Fe(2,2'bipy)_3]_2[Mo_8O_26]·6H_2O

A novel octamolybdate complex, [Fe(2,2?bipy)3]2[Mo8O26]6H2O has been synthesized via the hydrothermal technique, and it crystallizes in monoclinic, space group P21/c with two molecules in a unit cell: a = 1.21512(5), b = 1.36840(5), c = 2.18823(9) nm, b = 90.515(1), Mr = 2340.42, Z = 2, V = 3.6384(2) nm3, Dc = 2.136 g/cm3, F(000) = 2296, l(MoKa) = 0.071073 nm, = 1.813 mm-1, R = 0.0719 and wR = 0.1093 for 4058 observed reflections with I≥2s(I). The structure is characterized by the co-existence of octahedral [Fe(2,2?bipy)3]2+ cations and b-octamolybdate [Mo8O26]4- anions. The magnetic susceptibility data show a Curie-Weiss paramagnetic behavior (q = -5.201 K) in accordance with the spin-only ground state of FeⅡ ions. IR, UV-Vis, and EPR spectra are also briefly noted in this paper.

Study on the Magnetic Properties of MoFe_3S_4 Single Cubane-like Clusters Containing R_2dtc Ligands

Both cubane-like clusters MoFe_3S_4 (Me_2dtc)_5·2CH_2Cl_2 (1) and MoFe_3S_4(C_4H_8dtc)_5·2EtCN (2) were used to study the temperature-dependent behavior of the molar magnetic susceptibility. A spin coupling model was suggested and the fitting results agree with the model and structural and spectroscopic parameters.

Unit Construction in the Formation of Metal Clusters──Investigation on the Metal Cluster CompoundsContaining Fe_2S_2(CO)_6-units

The syntheses and structures of trinuclear Mo (W)-Fe-S cluster[MFe2S2(CO)8 (S,CNSEt2)]- (M=Mo, W), hexanuclear Fe-S cluster [Fe6S6-(CO)12]2- and undecanuclear Cu-Fe-S cluster [Cu5Fe6S6(CO)18(PPh3)2]-, containingFe2S2(CO)6-units bave been summarized and the important vestiges left in their struc-tures reflecting the formation processes of the clusters have been found and discussed.Further inspecting some other typical clusters a regular unit construction in the forma-tion of the metal cluster compounds containing Fe2S2(CO)6-units has been figured outand applied to speculate and predict several new cluster compounds containing Fe2S2(CO)6-units.

高温煅烧Mo改性的Fe/MgO催化剂用于制备管径分布均一的单壁碳纳米管

研究了在以甲烷化学气相沉积法制备单壁碳纳米管的过程中高温煅烧预处理(900℃煅烧10h)对Mo改性Fe/MgO催化剂的作用.发现这种预处理有利于Fe在催化剂中的稳定和分散,从而制备出管径均一的单壁碳纳米管.采用能谱元素分析、高分辨透射电镜、X射线衍射、比表面积测量、拉曼光谱和热重分析对样品进行了表征.结果表明,在碳纳米管生长的过程中,铁元素在催化剂表面富集,单壁碳纳米管生长于富集铁的纳米颗粒上,并存在碳管直径与铁颗粒尺寸的依赖关系.Mo存在时可煅烧形成FeMoO4复合氧化物,后者比MgFe2O4相更加稳定.Mo/Fe比例对提高单壁碳纳米管的生长密度、纯度与管径均一性等均有明显影响.上述研究对进一步精确控制制备单壁碳纳米管有重要意义.