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101.
Organolanthanide chloride complexes [(CH3OCH2CH2C5H4)2Ln(μ-Cl)]2 (Ln = La, Pr, Ho and Y) react with excess NaH in THF at 45°C to give the dimeric hydride complexes [(CH3OCH2CH2C5H4)2Ln(μ-H)]2, which have been characterized by IR, 1H NMR, MS and XPS spectroscopy, elemental analyses and X-ray crystallography. [(CH3OCH2CH2C5H4)2Y(μ-H)]2 crystallizes from THF/n-hexane at −30°C, in the triclinic space group P1 with a = 8.795(2) Å, b = 11.040(1) Å, c = 16.602(2) Å, = 93.73(1)°, β = 91.82(1)°, γ = 94.21(1)°, Dc = 1.393 gcm−3 for Z = 2 dimers. However, crystals of [(CH3OCH2CH2C5H4)2Ho(μ-OH)]2 were obtained by recrystallization of holmium hydride in THF/n-hexane at −30°C, in the orthorhombic space group Pbca with a = 11.217(2) Å, b = 15.865(7) Å, c = 17.608(4) Å, Dc = 1.816 gcm−3 for Z = 4 dimers. In the complexes of yttrium and holmium, each Ln atom of the dimers is coordinated by two substituted cyclopentadienyl ligands, one oxygen atom and two hydrogen atoms (for the Y atom) or two hydroxyl groups (for the Ho atom) to form a distorted trigonal bipyramid if the C(η5)-bonded cyclopentadienyl is regarded as occupying a single polyhedral vertex.  相似文献   
102.
[Ho5(H2O)16(OH)2As6W64O220]25?, a Large Novel Polyoxoanion from Trivacant Keggin Fragments The novel polyoxotungstate Na7K18[Ho5(H2O)16(OH)2As6W64O220] · 56 H2O ( 1 ) was synthesized in aqueous solution and characterized by X‐ray structure analysis, elemental analysis and IR spectroscopy. The anion in 1 represents one of the largest polyoxoanions known yet and exhibits an unusual arrangement of six Keggin units. It consists of six trivacant lacunary α‐B‐(AsW9O33)9? Keggin fragments which are connected by a bridging [Ho5W10(H2O)16(OH)2O22]29+ unit. The five HoIII atoms are coordinated by eight oxygen atoms, forming a square‐antiprism.  相似文献   
103.
104.
Holmium doped GaN diluted magnetic semiconductor thin films have been prepared by thermal evaporation technique and subsequent ammonia annealing. X-ray diffraction mea-surements reveal all peaks belong to the purely hexagonal wurtzite structure. Surface mor-phology and composition analysis were carried out by scanning electron microscopy and energy dispersive spectroscopy respectively. The room temperature ferromagnetic proper-ties of Ga1-xHoxN(x=0.0, 0.05) films were analyzed using vibrating sample magnetometer at room temperature. Magnetic measurements showed that the undoped films (i.e. GaN) exhibited diamagnetic behavior, while the Ho-doped (Ga0.95Ho0.05N) film exhibited a ferro-magnetic behavior.  相似文献   
105.
Multi-doped spinels, namely LiMn2O4 and LiZnxHoyMn2−xyO4 (x = 0.10–0.18; y = 0.02–0.10), for use as cathode materials for lithium-ion rechargeable batteries were synthesized via sol–gel method, using lauric acid as the chelating agent, to obtain micron-sized particles. The physical properties of the synthesized samples were investigated using differential thermal analysis, Fourier-transform infrared spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy, energy-dispersive X-ray analysis, and electrochemical methods. XRD showed that LiMn2O4 and LiZnxHoyMn2−xyO4 have high degrees of crystallinity and good phase purities. The SEM images of LiMn2O4 showed an ice-cube morphology with particles of size 1 μm. Charge–discharge studies showed that undoped LiMn2O4 delivered the discharge capacity of 124 mA h/g with coulombic efficiency of 95% during the first cycle, whereas doped spinels delivered discharge capacities of 125, 120, and 127 mA h/g in the first cycle with coulombic efficiencies of 96%, 91%, and 91%, respectively.  相似文献   
106.
The emission spectrum of the B3Π1-X1Σ+ band-system of the InCl molecule has been recorded on a Fourier transform spectrometer at an apodized resolution of 0.025 cm−1. The rotational structure of 1-0, 2-1, 0-0, 0-1, 1-2, 0-2, and 1-3 bands belonging to the B3Π1-X1Σ+ transition of In35Cl has been analyzed and accurate equilibrium rotational constants of the B3Π1 state, have been obtained. Precise Λ-doubling constants of the B3Π1 state (v=0, 1, and 2) are also reported for the first time.  相似文献   
107.
The complex Ho2(2-FC6H4COO)6?4H2O has been synthesized and structurally characterized by single crystal X-ray diffraction methods. The complex crystallizes in the triclinic system with space group P \(\bar 1\), lattice parameters a = 9.293(8) Å, b = 9.845(8) Å, c = 12.703(11) Å, α = 85.470(14)°, β = 87.537(12)°, γ = 62.485(11)°, V = 1027.5(15) Å3, Z = 1, Dcalc = 1.998 Mg/m3. The Ho3+ ion is in distorted monocapped square-antiprism coordination environment and is coordinated by nine oxygen atoms, seven from five 2-FC6H4COO2? groups, two from two water molecules. Two Ho3+ ions are linked together by four bridging carboxylate groups to form a binuclear molecule with inversion center.  相似文献   
108.
109.
The first high pressure study of solid hydrazinium monochloride has been performed by in situ Raman spectroscopy and synchrotron X‐ray diffraction (XRD) experiments in diamond anvil cell (DAC) up to 39.5 and 24.6 GPa, respectively. The structure of phase I at room temperature is confirmed to be space group C2/c by the Raman spectral analysis and Rietveld refinement of the XRD pattern. A structural transition from phase I to II is observed at 7.3 GPa. Pressure‐induced position variation of hydrogen atoms in NH3+ unit during the phase transition is attributed to the formation of N―H…Cl hydrogen‐bonds, which play a vital role in the stability and subsequent structural changes of this high energetic material under pressure. This inference is proved from the abnormal pressure shifts and obvious Fermi resonance in NH stretching mode of N2H5+ ion in the Raman experiment. Finally, a further transition from phase II to III accompanied with a slight internal distortion in the N2H5+ ions occurs above 19.8 GPa, and phase III persists up to 39.5 GPa. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
110.
– A Variant of the PaCl5 Structure Condensed to Double Strands in a Rare Earth Benzodinitrile Coordination Polymer Single crystalline transparent pink (1,3‐Ph(CN)2 = 1,3‐benzodinitrile, C6H4(CN)2) was obtained by the reaction of anhydrous holmium trichloride with a melt of 1,3‐benzodinitrile at 175 °C. The trichloride structure is broken up by the dinitrile ligands and re‐arranged to double strands of edge connected pentagonal bipyramids of chlorine and nitrogen atoms. The structure can be deduced from the PaCl5 structure type by condensation of two PaCl5 strands and exchange of two chlorine atoms with nitrile groups. The double strands exhibit ligand free cavities of 600–800 pm diameter.  相似文献   
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