隧道盲管内水体结晶影响因素及影响规律研究

隧道盲管水体结晶会阻塞盲管排水,给隧道结构的受力和铁路的安全运营造成很大的影响。文中结合我国西北某高铁在施工建设过程中出现的隧道盲管水体结晶现象,研究了影响盲管水体结晶的因素,涉及到二氧化碳、温度、水体的p H值等,并对各因素导致的水体结晶规律进行了分析。研究结果对于制定隧道盲管水体的结晶控制措施,具有重要的意义。

CO_(2)对隧道盲管水体结晶的影响及控制措施研究

隧道盲管的水体结晶会对盲管的排水造成很大的影响,甚至会给隧道的安全运营造成极大的隐患。结合我国西北某高铁在施工过程中隧道盲管水体结晶的具体情况,对空气中的二氧化碳导致盲管水体结晶的规律展开了研究,并在此基础上研发了隧道盲管的阻气排水设备,取得了良好的盲管内水体结晶控制效果。研究结果对类似隧道的盲管水体结晶控制,具有重要的意义。

罗布泊荒漠地区湖泊蒸发盐资源的形成及环境演化

通过地球卫星遥感资料和地面调查以及化学测试等综合研究,证实罗布泊地区存在大型现代液体钾盐矿床.用钻探材料及系统分析方法重建了20kaBP以来湖泊沉积序列和环境物性柱剖面,用天然水体五元体系稳定相图讨论了古湖泊湖水及现代湖水的饱和流结晶路线及成盐成矿演化趋势.结果证明,液体钾盐矿床的分布及成钾成矿环境受现代地壳运动作用下新生地堑构造系统的控制.

Dissolution kinetics and mechanism of gibbsitic bauxite and pure gibbsite in sodium hydroxide solution under atmospheric pressure

The crystal structure, morphology, dissolution kinetics and mechanism of gibbsitic bauxite and pure gibbsite in Na OH solution under atmospheric pressure were systematically investigated by XRD and SEM. The results show that the size of single crystal of gibbsite in gibbsitic bauxite is smaller than that in pure gibbsite, but the interplanar distance is larger than that of pure gibbsite, which result in more defects in the crystal and less energy needed to dissolve in alkaline solution for the gibbsitic bauxite. The dissolution kinetic equations of gibbsitic bauxite and pure gibbsite were established, and the corresponding activation energies were calculated to be 99.144 and 115.149 k J/mol, respectively.

Hydrothermal Synthesis and Structure Characterization of Compound Zn(Hpydc)_2(H_2O) (pydc=pyridine-2,5-dicarboxylate)

The hydrothermal reaction of ZnO, H3PO4(85%), (H2NCH2CH2)2NH and H2pydc results in the formation of a discrete mononuclear zinc(II) complex Zn(Hpydc)2(H2O). It crystallizes in monoclinic space group C2/c with a = 17.9947(8), b = 7.1875(3), c = 12.5895(4) , b = 110.802(2), V = 1522.14(10) 3, Z = 4, Mr = 415.61, (C14H10N2O9Zn), Dc = 1.814g/cm3, = 16.71cm-1, F(000) = 840, R = 0.0505, wR = 0.1144. Each zinc(II) is coordinated to two nitrogen and three oxygen atoms of which two nitrogen and two oxygen atoms are from two pydc ligands, and one oxygen atom from the coordinated water molecule to form an irregular polyhedral geometry. The complex is linked further into a three-dimensional structure through the weak interactions of hydrogen bonds between the two oxygen atoms. IR spectrum of the complex is also discussed.

Hydrothermal Synthesis and Structure of a New Molybdenum Phosphate: (NH_3CH_2CH_2NH_3)_(2.5)[Mo_5O_(15)(PO_4) (HPO_4)]·7.5H_2O

The title compound (C5N5H41P2Mo5O30.5) was synthesized under hydrothermal condition and its crystal structure was determined by X-ray diffraction. It belongs to triclinic system, space group P , with a=9.9645(6), b=10.8666(7), c=15.814(1)? α=71.482(3), β=88.528(2), γ=78.448(2)°, V=1589.4(2)3, Dc=2.510g/cm3, Z=2,μ=2.138mm-1,λ(MoKα) = 0.71073 ? F(000)=1180. The final R and wR were 0.0396 and 0.1052 for 6626 observed reflections with I ≥2σ(I), respectively. The result of the structure analysis indicates that the [Mo5O15(PO4) (HPO4)]5- anion in the title compound consists of five edge-sharing or corner-sharing MoO6 octahedra and two corner-sharing PO4 tetrahedra. Each MoO6 octahedron adopts distorted octahedral geometry.

Hydrothermal Synthesis and Crystal Structure of Trioxomolybdate: NaH_3OMo_3O_(10)

The hydrothermal reaction of Na2MoO4?2H2O, SmCl3 in acidified H2O/CH3CN solution gives rise to the title compound as colorless needle crystals, which was characterized by elemental analysis, IR and X-ray single-crystal diffraction techniques. Crystallographic data: Orthorhombic, Pnma, H3Mo3NaO11, Mr = 489.83, a = 8.411（2）, b = 7.566（2）, c = 14.359（3） ?, V = 913.8（3） ? 3, Z = 4, Dc = 3.560 g·cm-3, ( = 4.148 mm-1, F（000） = 912, the final R = 0.0649 and wR = 0.1569 for 1885 observed reflections with I ≥ 2σ（I）. The title compound consists of infinite chains built up by distorted {MoO6} octahedra via edge sharing, which are further connected into a three-dimensional framework by sodium ions and protoned water molecules.

Hydrothermal Synthesis and Crystal Structure of a New Phosphonate:{[Cu(1,10-phen)]_2-(H_2O_3PCH_2C_6H_4C_6H_4CH_2PO_3H)2-(HO_3PCH_2C_6H_4C_6H_4CH_2PO_3H)}_n

A new stepping chain {[Cu(1,10-phen)]2(H2O3PCH2C6H4C6H4CH2PO3H)2(HO3P- CH2C6H4C6H4CH2PO3H)}n 1 (C66H60Cu2N4O18P6) has been hydrothermally synthesized and charac- terized by single-crystal X-ray diffraction. It belongs to monoclinic, space group C2/c with a = 25.6114(4), b = 18.3781(2), c = 16.5180(3) ? b = 124.0610(10)? V = 6441.00(17) ?, Z = 4, Dc = 1.557 g/cm3, m(Mo-Ka) = 0.887 mm-1, F(000) = 3104, the final R = 0.0853 and wR = 0.1676 for 5585 independent reflections.

The Structure of Ammonium D,L-Tartrate

The single crystals of the title compound NH4+C4H5O6- (C4H9NO6, Mr = 167.1) were obtained from a hot aqueous solution containing L-glutamine and D,L-tartaric acid in mole ratio1:1.5. The crystal belongs to monoclinic space group P21/c with a = 7.646(2), b = 7.804(2), c = 11.502(3)? ?= 102.26(2)o, V = 670.7(3)?, Z = 4, F(000) = 352, Dc = 1.655 g.cm-3, m(MoKa) = 0.16 mm-1, R = 0.035, wR = 0.094 for 1028 observed reflections (I>2s(I)). The enatiomeric anions of the tartrate with both (2S,3S)- and (2R,3R)-configuration co-exist in the unit cell. The carbon skeleton assumes a coplanar arrangement with a torsion angle of 181.5o. The three- dimensional H-bonding network exists in the crystal. While tartrate groups link each other by H-bonds between carboxyl and hydroxyl groups, the ammonium cations insert between the tartrate groups to form a sandwich-like crystal structure.

Hydrothermal Synthesis and Structure of a Novel Molybdenum Phosphate: Na_4(H_3O) [Na(HPO_4)_2(PO_4)_4Mo_(18)O_(49)]·16H_2O

The title compound Na5H37P6Mo18O90 1 (Mr=1658) was synthesized under hydrothermal condition and its crystal structure was determined by X-ray diffraction. It crystallized in the monoclinic system, space group P21 with a =14.957(1), b =16.535(1), c = 16.159(1)?β=108.586(2)°, V=3787.85?, Dc =3.040g/cm3, Z=2,μ(MoK)=3.17mm-1, F(000)=3242. The final R and wR are 0.0500 and 0.1535 for 6643 observable reflections with I≥2?I), respectively. The result of structure analysis indicates that [Na(HPO4)2(PO4)4-Mo18 O49]5-anions 2 in 1 has the symmetry of C2V, in which each MoVIO6 octahedron is connected to adjacent PO4 tetrahedra through corner-sharing and to adjacent octahedra through edge-sharing or corner-sharing.

Hydrothermal Synthesis and Structure of a New Two-dimensional Zincophosphite: Zn_2(HPO_3)_3·H_2DACH(DACH = 1,2-diaminocyclohexane)

A new open-framework zincophosphite, Zn2(HPO3)3H2DACH 1, was hydro- thermally synthesized in the presence of 1,2-diaminocyclohexane (DACH) as structure-directing agent. Its structure was determined by single-crystal X-ray diffraction and further characterized by FTIR, elemental analysis, powder X-ray diffraction and thermogravimetric analysis. Crystal data for 1: Mr = 486.88, monoclinic, space group P21/c with a = 10.2287(11), b = 9.7624(11), c = 16.1686(18) , b = 92.573(2), V = 1612.9(3) 3, Z = 4, Dc = 2.005 g/cm3, F(000) = 984, = 3.314 mm-1 and S = 1.152. The final R = 0.0473 and wR = 0.1121 for 2456 observed reflections with I > 2s(I). The inorganic layer consisting of four- and eight-membered rings is constructed of alternating ZnO4 tetrahedra and HPO3 pseudo pyramids by sharing vertices. The organic template molecules reside in the interlayer region and interact with the inorganic network through H-bonds.

Crystal and Molecular Structure of 1-Methyl-4-(2-( 3,4-dimethoxyphenyl) vinyl) pyridinium 4-Tolylsulfonate Dihydrate C_(16)H_(18)NO_2^+·C_7H_7SO_3^-·2H_2O

The crystal structure of the title compound C16H18NO2+·C7H7SO3-·2H2O, (C23H29NSO7, Mr=463.53) has been determined by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system with space group P21/n, a=8.101(1), b=8.958(2), c=33.281(5)?,β= 94.910(1)(, V=2406.3(7)?3, Z=4, Dc=1.279g/cm3, μ=0.176mm-1, F(000)=984, final R=0.0409, and Rw=0.0860 for 4401 independent reflections. The result shows that in the crystal structure of the title compound the planar cations have two configurations with equal occupation ratio and are antiparally packed through π…π interactions. Similar packing energies in A and B are probably the main factor that leads to the disorder structure.

Hydrothermal Synthesis and Structure of a Novel Two-dimensional Complex:[Ni_(0.5)(H_2O)_(1.5){Ni(en)_2}_3V_(18)O_(42)(Cl)]3.5H_2O

A novel two-dimensional compound [Ni0.5(H2O)1.5{Ni(en)2}3V18O42(Cl)]3.5H2O 1 has been hydrothermally synthesized and characterized by IR, elemental analysis, and single-crystal X-ray diffraction analysis. Crystal data for 1: monoclinic, space group C2/c with a = 12.824(3), b = 27.873(6), c = 21.092(4) , b = 92.93(3), V = 7529(3) 3, Z = 4, Dc = 2.012 g/cm3, Mr = 2280.56, F(000) = 4476 and m = 3.092 mm-1. The final R and wR are 0.0769 and 0.1783, respectively for 4203 observed reflections with I>2s(I). The structure consists of [V18O42(Cl)]7- clusters linked by trans- {Ni(en)2} groups into linear chains, while cis-{Ni(en)2} groups provide the cross-linking adjacent chains to form a two-dimensional structure.

Syntheses,Structures and Characterizations of Two New Vanadium(V) Complexes:[PyH][V^VO_2(C_(14)H_9N_2O_3Br)] and [V^VO(C_(14)H_9N_2O_3Br)(OCH_3)]

The new oxovanadium (V) complex, [PyH][VO2(L)] 1 (salicyladehyde 5-bromo salicyloylhydrazone is abbreviated as H2L; Hpy is protonated pyridine) was obtained from a refluxed solution of VOSO4 and H2L in acetonitrile-methanol-pyridine. Similarly, another new complex, [VO(L)(OCH3)] 2 was synthesized by refluxing VOSO4 and H2L in methanol-pyridine. Crystal data for 1: C19H15N3O5BrV, Mr= 496.2, monoclinic, P21/n, a = 7.1885(3), b = 9.2718(3), c = 28.803(1) A, β = 96.185(1)°, Z = 4 and V = 1908.6(1) A3; for 2: C15H12N2O5BrV, Mr= 431.1, monoclinic, P2,/n, a = 12.202(2), b = 8.045(2), c = 16.604(3) A, β = 101.29(3)°, Z = 4 and V = 1598.4(2) A3. The structures of 1 and 2 have been determined by X-ray analyses and reveal that the coordination environments of V atoms in both complexes are of square-based pyramid. Three of the four based donor atoms are from the tridentate 'ONO' donor ligand while the fourth is one terminal oxygen atom with the V(1) - O(3) distance 1.646(4) A for 1 and one -OCH3 group with the V(1)-O(3) distance 1.753(3) A for 2. The V(1)-O(4) terminals occupy the axial sites in both cases. The complexes are also characterized by IR and 1H NMR spectroscopies.

Hydrothermal Synthesis and Crystal Structure of [H_4As_8V_(14)O_(42)(H_2O)]·6H_2O

The title compound [H4As8V14O42(H2O)]6H2O 1 has been synthesized and characterized by elemental analysis, IR, and single-crystal X-ray diffraction analysis. It crystallizes in trigonal, space group R3c with a = b = 36.447(6), c = 21.485(5) ? V = 24717(8) 3, Z = 18, Mr = 2114.66, Dc = 2.557g/cm3, F(000) = 17928, m = 7.149 mm-1, R = 0.0792 and wR = 0.1265. The [H4As8V14O42- (H2O)] cluster consists of fourteen VO5 square pyramids linked by four As2O5 handle-like units.

Hydrothermal Synthesis and Crystal Structure of [(CH_3CH_2)_4N]_4[(La_(12)(OH)_(12)MoO_(29) )], A Novel Cluster Compound with a MoO_5 Hexahedron Center Surrounded by La-O Octahedron

A novel compound [(CH 3CH 2) 4N] 4[(La 12 (OH) 12 MoO 29 )] was synthesized by hydrothermal reaction. The single crystal X ray diffraction shows that the compound crystallized in the monoclinic space group C2/c ; a =2 5729(4) nm, b =1 4318(1) nm, c =2 1217(4) nm, β =111 56(1)°, V =6 8235(7) nm 3, Z =4, R =0 0751. The basic building blocks of the crystal structure included one MoO 5 hexahedron and twelve LaO 6 octahedra which shared a common edge to form a [(La 12 (OH) 12 MoO 29 )] 4- unit. These units were held together by the [(CH 3CH 2) 4N] + ions.

Aminopropyl-containing ionic liquid based organosilica as a novel and efficient adsorbent for removal of crystal violet from wastewaters

Herein a novel aminopropyl-containing ionic liquid based organosilica(ILOS-NH_2) is prepared, characterized and applied as effective adsorbent for removal of crystal violet(CV) dye from wastewater. The ILOS-NH2 material was synthesized by hydrolysis and co-condensation of 1,3-bis-(3-trimethoxysilylpropyl)-imidazolium chloride(BTMSPIC) under acidic conditions followed by treatment with 3-aminopropyl-trimethoxysilane in toluene under reflux conditions. This material was characterized using scanning electron microscopy(SEM), diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS), thermal gravimetric analysis(TGA) and energy dispersive X-ray analysis(EDAX). The material was effectively used in the removal of crystal violet at ambient temperature and showed high capacity and stability under applied conditions. The efficacy of p H, contact time, adsorbent dose, initial dye concentration, temperature, and isotherm studies and the applicability of pseudo-first, second order and Elovich kinetic models have also been investigated.

Superconductivity at 10.4 K in a novel quasi-one-dimensional ternary molybdenum pnictide K2Mo3As3

Here we report the discovery of the first ternary molybdenum pnictide based superconductor K2Mo3As3. Polycrystalline samples were synthesized by the conventional solid state reaction method. X-ray diffrac- tion analysis reveals a quasi-one-dimensional hexagonal crystal structure with （Mo3As3）2 linear chains separated by K^＋ ions, similar as previously reported K2Cr3As3, with the space group of P-6m2 （No. 187） and the refined lattice parameters a = 10.145（5） A and c = 4.453（8） A. Electrical resistivity, magnetic susceptibility, and heat capacity measurements exhibit bulk superconductivity with the onset Tc at 10.4 K in K2Mo3As3 which is higher than the isostructural Cr-based superconductors. Being the same group VIB transition elements and with similar structural motifs, these Cr and Mo based superconductors may share some common underlying origins for the occurrence of superconductivity and need more investigations to uncover the electron pairing within a quasi-one-dimensional chain structure.

Uranyl oxamate hydrates: hydrothermal synthesis, crystal structure, photophysical properties, and selective crystallization

Presented here are two isostructural uranyl coordination polymers [UOe（EDO）（H2O）]· H2O （1） and [UO2（BDO）（H2O）]-2H2O （2） （EDO2---ethylene-1,2-dioxamate; BDO2 =butylene-1,2-dioxamate） with identical stepwise zigzag chain structure and distinct interchain hydrogen bonding interaction, prepared from hydrothermal reaction of DEEDO or DEBDO （DEEDO- diethyl ethylene-1,2-dioxamate; DEBDO--diethyl butylene-l,2-dioxamate） with uranyl ions. The monomeric uranyl-based fluorescence emissions of compounds 1 and 2 are red-shifted by about 6 and 5 nm respectively, compared to that of uranyl nitrate hexahydrate. Compound 1 has stronger emission than compound 2, but both their emissions exhibit triple-exponential decay. The photophysics of uranyl oxalate trihydrate was also investigated for comparison. The selective crystallization of compound 1 in alkaline solution was applied to the sequestration of uranyl ions, showing a kinetic preference.

Unusual reaction of a tungsten alkylidyne complex with water.Formation,characterization,and crystal structures of oxo trimers

The reaction of the alkyl alkylidyne W（CH2CMe3）3（=CSiMe3） （1） with H20 in THF and with D20 in benzene-d6 gave two new trimeric oxo complexes： W3O3（μ=O）3（CH2CMe3）6（THF）3 （2） and [W303（μ=O）3（Ch2CMe3）6（D2O）3] 2benzene-d6 （3.2benzened6）, respectively, each containing two alkyl ligands per W atom. This is in contrast to the dimer W2o（β-O）（CH2CMe3）6, containing three alkyl ligands per W atom, from the previously reported reaction of the alkyl alkylidyne analog W（CH2CMe3）3- （=-CCMe3） with H2O. In the reaction of 1 with D20 in THF, an unstable intermediate W2O2（μ-O）（CD2SiMe3）2（CH2CMe3）4 （4-d4） was identified. Kinetic studies of the reactions of 1 with excess H2O and D2O in THF-ds, yielding 4 and 4-d4, respectively, give a kinetic isotope effect （KIE） of 3.46（3） at 298（1） K, suggesting that the disappearance of 1 is a rate-determining step.