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1.
为了研究溶剂预处理对低阶煤的固有大分子结构的影响,本研究对锡林郭勒褐煤(XLL)和神府次烟煤(SFC)分别进行了四氢呋喃(THF)索氏抽提、二硫化碳/N-甲基-2-吡咯烷酮(CS2/NMP)混合溶剂抽提及热溶处理,并对所得抽余煤进行了傅里叶红外漫反射光谱分析(DRIFT)、热重分析(TGA)、压汞法分析(MI)和溶胀度测定。结果表明,溶剂抽提导致煤大分子结构重排和再缔合。其中,THF索式抽提和CS2/NMP混合溶剂抽提可以改变非共价键交联作用,特别是氢键作用分布,从而不同程度地松弛煤大分子结构。然而,高温溶剂热溶处理主要促进了煤大分子的共价键交联,尤其是对锡林郭勒褐煤(XLL)。所有抽取煤的溶胀都受Fickian扩散控制,且所有抽取煤的溶胀活化能都低于原煤。  相似文献   

2.
四甲基双硅桥联环戊二烯基钠与无水三氯化稀土在THF溶剂中反应合成了标题配合物Me4Si2(C5H4)2LnCl[Ln:3Nd,4Sm,5Gd,6Y]和配合物Me4Si2(C5H4):Ln(C5H5)(THF)n[Ln:1La,n=1;2Pr,n=0].通过元素分析、1HNMR、13CNMR和MS确证了配合物的结构,在THF溶液中重结晶获得配合物4的单晶,x射线衍射证明晶体结构为二聚体,4为单斜晶系,空间群为P21/c,晶体学数据a=1.2982(3)nm,b=1.2269(3)nm,c=1.3681(2)nm,β=96.79(2)°,V=2.162(1)nm3,Z=2,Dx=1.53g/cm3,偏差因子R=0.068.  相似文献   

3.
李波  周海燕  马海燕  黄吉玲 《化学学报》2023,(10):1280-1294
设计并合成了12个亚乙基桥联双茚类锆、铪配合物meso-/rac-1~7[ansa-C2H4-(3-R-4,7-Me2-C9H3)2MCl2:M=Zr R=nBu (meso-/rac-1),iPr (meso-2),CH2Cy (meso-/rac-3),Bn (meso-/rac-4),CH2C6H4(4-CH3)(meso-/rac-5);M=Hf,R=CH2C6H4(4-CH3)(meso-/rac-7);ansa-C2H4-{2-Me-3-Bn-5,6-[1,3-(CH2)3]C9  相似文献   

4.
炼厂干气中回收乙烯是扩宽C2H4来源的有效途径,但C2H4和C2H6物理性质和分子尺寸非常接近,分离困难.金属有机骨架材料(MOFs)近年来在低碳烃分离领域展现出广阔的前景.本工作采用氨吸附改性调节UTSA-280的结构,通过一维直孔道大小的调节实现C2H4/C2H6的高效分离.改性后的UTSA-280具有独特的超微孔结构能提升C2H4的吸附,而完全不吸附稍大的C2H6,实现理想的C2H4/C2H6吸附选择性(>1000).结果表明,改性后的UTSA-280的C2H4吸附量可提高至2.83 mmol/g,与未改性的材料相比增加29%,并且能阻挡C2H6的吸附,最终达到>1200的C2H4/C2H6选择性.蒙特卡罗分子模拟(GCMC)计算C2H4/C2H6混合气体(1:1)的吸附得出,改性后UTSA-280孔内的C2H4吸附相比于C2H6具有更多的吸附分布.通过C2H4/C2H6混合气体穿透实验测试,改性后的UTSA-280材料能展现出48 min以上的分离时间,相比于未改性的材料,分离性能提升近1倍.  相似文献   

5.
两个含N-皮考林酰肼铁配合物的合成和结构表征   总被引:6,自引:0,他引:6  
合成了含N-乙酰皮考林酰肼(简写为Haphz)的铁配合物[Fe2(aphz)2(μ-CH3O)2Cl2]·CH3OH(1,C19H26Cl2Fe2N6O7,Mr=633.06)和含N-苯甲酰皮考林酰肼(简写为Hphphz)的铁配合物Fe(phphz)Cl2(2,C13H10Cl2FeN3O2,Mr=366.99).2个配合物均属三斜晶系,空间群为P  相似文献   

6.
本研究采用密度泛函理论,通过比较吸附量、吸附能以及态密度和电荷差分密度的分析,探究了不同金属氧化物耦合吡咯氮生物炭(CN5@MOx,MOx=ZnO、CaO、Na2O)表面CO2与C3H6O(CO2&C3H6O)的吸附机理。首先从CO2/C3H6O单组分方面计算了其在CN5@MOx表面吸附量和吸附能,计算结果表明,在333 K、100 kPa时CN5@Na2O表面对CO2/C3H6O单组分吸附量分别为3.65、15.34 mmol/g,吸附能分别为-145.86、-132.47 kJ/mol,均高于CO2/C3H6O单组分在CN5@CaO及CN5@...  相似文献   

7.
以Na2PdCl4与(2-NC5H4)C(H)=N(C6H4OH-2)在不同溶剂中合成了两个钯配合物 Pd{2-(NC5H4)C(H)=N[2-(OH)C6H4]}Cl2(Complexe 1)和 Pd{2-(NC5H4)C(H)=N[2-(O)C6H4]}Cl(Complexe 2)。X射线单晶衍射确定了配合物的分子结构,在配合物1和2中,氯离子的配位个数对所形成的配合物的四边形结构产生一定的影响。两种钯配合物的催化活性通过空气中在醇溶剂体系下4-碘甲苯和苯硼酸的Suzuki-Miyaura反应进行评价。结果显示:催化产物4-甲基联苯的产率可达98.72%和92.31%,副产物联苯的产率小于1.15%,进一步通过配合物的单晶结构数据分析了不同配位模式对催化活性的影响。   相似文献   

8.
通过等体积浸渍方法制备了添加CeO2助剂的用于C2H4/C2H6吸附分离的CuCl/活性炭(AC)吸附剂,使用氮气吸附-脱附曲线、X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、能量分散X射线光谱(EDX)等分析方法对吸附剂进行了表征.结果表明,吸附剂表面Cu(II)在氮气气氛焙烧过程中被部分还原成Cu(I).重点研究了Ce元素的添加对于吸附剂的C2H4/C2H6吸附分离性能的影响,等温吸附曲线结果表明添加了CeO2的吸附剂通过降低乙烷的吸附容量从而显著提高了吸附分离性能. XRD及XPS结果表明,和未添加助剂样品相比,其表面晶体团簇较小,分散性更好, Cu(II)还原程度更高.添加CeO2的吸附剂样品5Ce50Cu(CeO2和CuCl2的质量分数(w)分别为5%和50%)获得了最好的吸附分离效果,相对于未添加CeO2的样品50Cu,其在660 kPa下的吸附选择性由4.2提升到8.7.  相似文献   

9.
D-葡萄糖与氯化稀土配合物的合成及红外光谱研究   总被引:8,自引:0,他引:8  
以非水溶剂为介质合成了D-葡萄糖、氯化稀土、吡啶的混配多元配合物,并进行了元素分析和红外光谱测定。研究结果表明,D-葡萄糖和溶剂吡啶同时参与了配位,该配合物的组成为:Ln(C6H12O6)(C5H5N)Cl3(Ln=La,Ce,Pr,Nd,Sm等).本文还对配合物的可能结构进行了讨论。  相似文献   

10.
四芳基卟啉锰配离子的TCNQ电荷转移盐的合成和物理性质   总被引:3,自引:0,他引:3  
合成了13个四芳基卟啉锰配离子的TCNQ电荷转移盐[TAPMn][TCNQ]n(TAPH2=α,β,γ,δ-四芳基卟啉;A=C6H5,4-CH3C6H4,4-CH3OC6H4,4-ClC6H4,3-ClC6H4,3-FC6H4,4-(CH3)2NC6H4,2,4-Cl2C6H3;TCNQ=7,7,8,8-四氰基对苯醌二甲烷;n=1,2).通过元素分析、IR、XPS、ESR、磁化率和电导率对其进行了表征.结果表明:这些电荷转移盐分子中存在TCNQ0和TCNQ-,且TCNQ0和TCNQ-之间存在相互作用,部分电荷从[TCNQ]n-向[TAPMn]+转移,导致化合物中的锰表现为混合价态.复合盐的室温电导率在10-7~10-10S·cm-1,属于有机半导体,简单盐的室温电导率小于10-11S·cm-1.  相似文献   

11.
用等体积的二硫化碳(CDS)与丙酮的混合溶剂萃取了准东次烟煤得到可溶物,然后依次用石油醚(PE)和CDS萃取该可溶物为PE萃取物(E1)和CDS萃取物(E2)。在硅胶层析柱中依次用PE和30%的CDS/PE对E2进行洗脱,富集了长链烷醛(LCNAs,C18~27)并用气相色谱/质谱联用仪分析了LCNAs。分级萃取和柱层析提供了从中低阶煤中富集LCNAs的有效方法。LCNAs可能是煤中重要的生物标志物。  相似文献   

12.
The substitution reactions of XC6H4COCl [X=2-, 3-, or 4-CH3; 2-, 3-, or 4-CH3O; 2-, or 4-I; or 2-, 3-, or 4-NO2] and YC6H4COONa [Y=2-, 3-, or 4-CH3; 2-, 3-, or 4-CH3O; 2-I; 4-NO2; or H] in a two-phase H2O/CH2Cl2 medium using pyridine-1-oxide (PNO) as an inverse phase transfer catalyst were investigated. In general, the kinetics of the reaction follows a pseudo-first-order rate law, with the observed rate constant being a linear function of the concentration of PNO in the water phase. In contrast to other analogous reactions, the hydrolysis reaction of 2-, 3-, or 4-NO2C6H4COCl in H2O/CH2Cl2 medium is catalyzed considerably by PNO and reaches an equilibrium. In the PNO-catalyzed reaction of XC6H4COCl and XC6H4COONa in H2O/CH2Cl2 medium, the order of reactivities of XC6H4COCl toward reaction with PNO in CH2Cl2 is 2-IC6H4COCl>4-IC6H4COCl>(C6H5COCl,3-CH3OC6H4COCl)>3-CH3C6H4COCl>(2-CH3C6H4COCl,4-CH3C6H4COCl)>4-CH3OC6H4COCl>2-CH3OC6H4COCl. Combined with the results of other analogous reactions, good Hammett correlations with positive reaction constant were obtained for the meta- and para-substituents, which supports that the XC6H4COCl–PNO reaction in CH2Cl2 is a nucleophilic substitution reaction.  相似文献   

13.
利用ASE 350型超声快速溶剂抽提仪,在高温高压下对神华长焰煤(SH)进行二硫化碳/N-甲基吡咯烷酮(CS2/NMP)混合溶剂抽提,抽提率约为25%(质量分数)。将得到的抽提残渣(SHC)进行钌离子催化氧化(RICO)降解反应,并对产物进行了离子色谱(IC)检测和以四甲基氢氧化铵(TMAH,25%甲醇溶液)为衍生化试剂的热辅助-在线甲酯化后的气质联用仪(GC-MS)检测分析。结果表明,神华长焰煤大分子结构中含有C2~28烷基侧链,C2~22的连接芳环的烷基桥链,有相对较多的醚键链接的芳环结构存在,芳环缩合程度相对较低(主要以含有2~4个苯环的共轭结构为主),有较多的醚键链接的芳环结构及羟基(-OH)、羰基(=C=O)和甲氧基(-OCH3)等形式含氧基团以及含硫和氮等杂原子化合物的存在。  相似文献   

14.
The study of the reactivity of R---CH=N---(C6H4-2-SMe) with R=C6H5 or 2,4,6-Me3-C6H2 with palladium(II) salts is reported. These studies have allowed us to prepare and characterize the coordination complexes: cis-[Pd{R---CH=N---(C6H4-2-SMe)}Cl2] {R=C6H5 or 2,4,6-Me3-C6H2} and the cyclopalladated compounds [Pd{C6H4---CH=N---(C6H4-2-SMe)}Cl] and [Pd{(2-CH2-4,6-Me2-C6H2)---CH=N---(C6H4-2-SMe)}Cl]. The X-ray crystal structures of the latter complexes reveal that the thioimines act as a [Csp2, phenyl,N,S] and as a [Csp3, N,S] terdentate group, respectively. The study of the reactions of the cyclopalladated compounds with PPh3 is also reported.  相似文献   

15.
LnCl3 (Ln=Nd, Gd) reacts with C5H9C5H4Na (or K2C8H8) in THF (C5H9C5H4 = cyclopentylcyclopentadienyl) in the ratio of 1 : to give (C5H9C5H4)LnCl2(THF)n (orC8H8)LnCl2(THF)n], which further reacts with K2C8H8 (or C5H9C5H4Na) in THF to form the litle complexes. If Ln=Nd the complex (C8H8)Nd(C5H9C5H4)(THF)2 (a) was obtained: when Ln=Gd the 1 : 1 complex [(C8H8)Gd(C%H9)(THF)][(C8H8)Gd(C5H9H4)(THF)2] (b) was obtained in crystalline form.

The crystal structure analysis shows that in (C8H8)Ln(C5H9C5H4)(THF)2 (Ln=Nd or Gd), the Cyclopentylcyclopentadieny (η5), cyclooctatetraenyl (η8) and two oxygen atoms from THF are coordinated to Nd3+ (or Gd3+) with coordination number 10.

The centroid of the cyclopentadienyl ring (Cp′) in C5H9C5H4 group, cyclooctatetraenyl centroid (COTL) and two oxygens (THF) form a twisted tetrahedron around Nd3+ (or Gd3+). In (C8H8)Gd(C5H9C5H4)(THF), the cyclopentyl-cyclopentadienyl (η5), cyclooctatetraenyl (η8) and one oxygen atom are coordinated to Gd3+ with the coordination number of 9 and Cp′, COT and oxygen atom form a triangular plane around Gd3+, which is almost in the plane (dev. -0.0144 Å).  相似文献   


16.
Reaction of YbI2 with two equivalents of cyclopentylindenyl lithium (C5H9C9H6Li) affords ytterbium(II) substituted indenyl complex (C5H9C9H6)2Yb(THF)2 (1) which shows high activity to ring-opening polymerization (ROP) of lactones. The reaction between YbI2 and cyclopentylcyclopentadienyl sodium (C5H9C5H4Na) gives complex [(C5H9C5H4)2Yb(THF)]2O2 (2) in the presence of a trace amount of O2, the molecular structure of which comprises two (C5H9C5H4)2Yb(THF) bridged by an asymmetric O2 unit. The O2 unit and ytterbium atoms define a plane that contains a Ci symmetry center.  相似文献   

17.
研究了银溶胶体系表面增强拉曼散射光谱的溶剂效应,发现在不同的溶剂中,银溶胶的聚集状态不同,当胶粒带电荷时,溶剂还能影响分子在胶粒表面的吸附,溶剂通过改变胶粒的聚集状态及分子在胶粒上的吸附这两个因素影响银溶胶体系的SERS光谱。  相似文献   

18.
The coordinatively unsaturated uranium(IV) complex U[N(C6H5)2]4 has been prepared via the stoichiometric reaction of diphenylamine with [(Me3Si)2N]2 H2. U[N(C6H5)2]4 coordinates Lewis bases such as Et2O, THF, pyridine or (EtO)3PO, based on electronic absorption spectroscopy and 1H NMR studies. Exchange between U[N(C6H5)2]4 and U[N(C6H5)2]4(L), where L is THF or pyridine, is rapid on the NMR time-scale between 307 and 323 K. Measurement of equilibrium constants for L = THF provides ΔH and ΔS values of −60 kJ mol−1 and −1.8 × 102 J K−1 mol−1, respectively. U[N(C6H5)2]4 coordinates and binds (EtO)3PO much more tightly (Keq = & > 104 M−1) than THF or pyridine with the exchange rate between U[N(C6H5)2]4 and U[N(C6H5)2]4[OP(OEt)3] being close to the NMR time-scale.  相似文献   

19.
The reaction of LnCl_3 with K _9H_7(C_9H_7=indenyl)andK_2C_8H_8(C_8H_8=cyclooctatetraene)in tetrahydrofuran(THF)give thecorresponding complexes(η~5-C_9H_7)Ln(η~8-C_8H_8)·2THF.The synthesis of(η~5-C_9H_7)Ln(η~8-C_8H_8)·2THF(Ln=Pr,Nd)and crystal structure of(η~5-C_9H_7)Pr(η~8-C_8H_8)·2THF are described.  相似文献   

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