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31.
Artificial neural networks are trained to forecast the plasma disruption in HL-2A tokamak. Optimized network architecture is obtained. Saliency analysis is made to assess the relative importance of different diagnostic signals as network input. The trained networks can successfully detect the disruptive pulses of HL-2A tokamak. The results obtained show the possibility of developing a neural network predictor that intervenes well in advance for avoiding plasma disruption or mitigating its effects.  相似文献   
32.
A new metal-organic coordination complex [Zn(H2BPTC)(phen)2]n·3nH2O (BPTC =3,3',4,4'-benzophenone tetracarboxylate, phen = 1,10-phenanthroline) 1 has been obtained from hydrothermal reaction and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. In compound 1, the zinc cation is hexa-coordinated with two carboxylate oxygen atoms from one H2BPTC ligand and four nitrogen atoms from two different phen ligands, showing a slightly distorted octahedral geometry. Crystal data: C41H30N4O12Zn, Mr = 836.06, monoclinic,P21/c, a = 14.2714(9), b = 16.9386(10), c = 15.0151(9) (A),β = 101.3420(10)°, V= 3558.8(4) (A)3, Dc= 1.560 g/cm3,μ(MoKα) = 0.766 mm-1, F(000) = 1720, Z = 4, R = 0.0439 and wR = 0.1157 for 4123observed reflections with I > 2σ(I).  相似文献   
33.
A new metal-organic complex [Pb2(PDB)2(phen)]n·nH2O (H2PDB=pyridine-3,4-dicarboxylic acid,phen=1,10-phenanthroline) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis,IR spectrum,TG and single-crystal X-ray diffraction.The compound crystallizes in triclinic,space group P1 with a=7.2472(5),b=10.6966(8),c=16.2376(12),α=98.2960(10),β=91.6430(10),γ=97.4810(10)o,V=1233.53(16)3,C26H16O9N4Pb2,Mr=942.81,Dc=2.538 g/cm3,μ(MoKα)=13.697 mm-1,F(000)=872,Z=2,the final R=0.0247 and wR=0.0654 for 3886 observed reflections (I 2σ(I)).In the crystal structure,the Pb(1) atom is six-coordinated with four carboxylate oxygen atoms from three different PDB ligands and two nitrogen atoms from phen ligand,showing a distorted octahedral geometry;the Pb(2) atom is four-coordinated with four carboxylate oxygen atoms from four different PDB ligands,showing a distorted tetrahedral geometry.It exhibits a three-dimensional supramolecular network structure formed by hydrogen bonds and π-π interactions.  相似文献   
34.
A new copper(Ⅱ) compound has been prepared and fully characterized by elemen-tal analysis,IR,TG and single-crystal X-ray diffraction.The compound [Cu(4-hba)2(inta)(H2O)]·H2O (4-hba=4-hydroxybenzoic acid,inta=isonicotinamide) 1 crystallizes in the monoclinic system,space group P21/c with a=7.590(5),b=11.027(5),c=23.761(5),β=102.5740(10)o,V=1974.1(16) 3,Mr=991.84,Z=2,Dc=1.669 g/cm3,F(000)=1020,μ=1.166 mm-1,R=0.0353 and wR=0.0604 for 3166 observed reflections (I 2σ(I)).In compound 1,the copper cation is penta-coordinated with two carboxylate oxygen atoms from two different 4-hba ligands,two oxygen atoms from two coordinated water molecules and one nitrogen atom from inta ligand,showing a slightly distorted square-pyramidal geometry.  相似文献   
35.
通过水热法合成了2个金属-有机配位聚合物[Mn(dipha)(1,3-bix)]n·nH2O(1)和[Cd2(NIPH)2(bimb)2.5(H2O)]n·3nH2O(2)(H2dipha=2,2’-联苯二甲酸,1,3-bix=1,3-双(咪唑基-1-甲基)-苯,H2NIPH=5-硝基间苯二甲酸,bimb=1,4-双(咪唑基-1-甲基)-丁烷)。并对其进行了元素分析、红外光谱、热重和X-射线单晶衍射测定。这2个配合物通过氢键和π-π相互作用形成了超分子网状结构。此外还研究了配合物2的荧光性质。  相似文献   
36.
采用水热法合成了1个二维缠结金属有机框架化合物[Cu(bbi)0.5(boba)]n1)(bbi=1,1’-(1,4-丁烷基)-二(咪唑);H2boba=4,4’-(丁烷-1,4-二氧基)-二苯甲酸),并通过元素分析、红外光谱和单晶X-射线衍射对其进行了结构表征。结构分析显示:化合物1是具有聚轮烷和聚锁烃结构特征的三重平行穿插网络。此外还研究了它的荧光和热稳定性。  相似文献   
37.
通过水热法合成了2个金属-有机配位聚合物[Mn(dipha)(1,3-bix)]n·nH2O(1)和[Cd2(NIPH)2(bimb)2.5(H2O)]n·3nH2O(2)(H2dipha=2,2′-联苯二甲酸,1,3-bix=1,3-双(咪唑基-1-甲基)-苯,H2NIPH=5-硝基间苯二甲酸,bimb=1,4-双(咪唑基-1-甲基)-丁烷)。并对其进行了元素分析、红外光谱、热重和X-射线单晶衍射测定。这2个配合物通过氢键和π-π相互作用形成了超分子网状结构。此外还研究了配合物2的荧光性质。  相似文献   
38.
lINTRODUCTIONThefirstheteronucleartransitionmetalclusterHFeCo,(Co),,wassynthesizedbyChinit13in196Obyusingthepyrolysisofmeta1carbonyldimers.Analysisofcar-bonylIRspectraandX-raypowderpatternsindicatedthatthiscompoundisisostruc-tural.withCo'(CO),,andthushasC,.symmetry(".MaysE'-'ihascarriedoutIRspectraandmassspectraonthiscompoundandkineticisotopestudiesontheprotona-tionoftheanion[FeCo,(CO),,j-,andproposedonthebasisofthisevidencethatthehydrogenatommightbelocatedinthecenterofthecluster.…  相似文献   
39.
Two new oleanane-type triterpenoid glycosides, 3-O-β-D-xylopyranosyl-(1→2)-α-L-arabinopyranosyl-(1→3)-[β-D-glucuronopyranosyl-(1→2)]-β-D-glucuronopyranosyl-22α-angeloyloxyolean-12-ene-15α,16α,28-triol(1) and 3-O-β-D-xylopyranosyl-(1→2)-α-L-arabinopyranosyl-(1→3)-[β-D-glucuronopyranosyl-(1→2)]-β-D-glucuronopyranosyl-21β-acetyl-22α-angeloyloxyolean-12-ene-16α,28-diol (2) were isolated from the stems of Camellia oleifera Abel. Their structures were elucidated by means of spectroscopic methods and chemical evidence. The cytotoxic activities of compounds 1–2 were evaluated against five human tumour cell lines (HCT-8, BGC-823, A5049, and A2780). Compounds 1–2 showed cytotoxic activity against five human cancer cell lines, with IC50 values ranging from 3.15 to 7.32 μM.  相似文献   
40.
The title complex, [Mn(DPPZ)(PZDC)(H2O)] 1 (DPPZ = dipyrido[3,2 -a:2',3'- c]phenazine and H2PZDC = pyrazine-2,3-dicarboxylic acid), has been hydrothermally synthesized and structurally characterized by X-ray single-crystal diffraction, elemental analyses, IR, TG- DTA and magnetic susceptibility measurement. It crystallizes in triclinic, space group P1^- with a = 6.6842(5), b = 7.5741(6), c = 20.5755(15)A, α = 90.1160(10), β = 97.0560(10), γ = 97.3350(10)°, V= 1025.16(13)A^3, Z = 2, MnC24H14N6O5, Mr= 521.35, Dc= 1.689 g/cm^3, F(000) = 530, μ(MoKa) = 0.699 mm^-1, R = 0.0366 and wR = 0.0810. Compound 1 contains one- dimensional chains which are further stacked through π-π interactions to form a 3D supramolecular architecture. The water molecule O(1W) is involved in hydrogen bonding interactions with symmetric carboxylate oxygen atom 0(4) at (x+ 1, y+1, z) and symmetric PZDC nitrogen atom N(6) at (1-x, 1-y, 1-z), which completes the structure of 1. Magnetic susceptibility measurement indicates that the compound behaves a weak antiferromagnetic exchange interaction.  相似文献   
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