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1.
The crystal structure of [NpO2{OC(NH2)2}5]ClO4·H2O and [NpO2Cl{OC(NH2)2}4] was studied by X-ray diffraction. The electronic absorption spectra of these complexes were recorded. The coordination polyhedron of Np in both complexes is a distorted pentagonal bipyramid. There is no cation-cation interaction of neptunyl cations in these complexes. 相似文献
2.
The compound [Co(NH3)6][PuO2(C2O4)2] · 3H2O was studied by single crystal X-ray diffraction. The structure contains dimeric complex anions [PuO2(C2O4)2]
2
6−
in which the coordination polyhedra of the Pu atoms are distorted pentagonal bipyramids sharing a common equatorial edge.
In going from [Co(NH3)6] · [NpO2(C2O4)2] · 3H2O to [Co(NH3)6][PuO2(C2O4)2] · 3H2O, the An-O distances, both axial (in the actinyl group) and equatorial, decrease virtually isotropically.
__________
Translated from Radiokhimiya, Vol. 47, No. 5, 2005, pp. 419–422.
Original Russian Text Copyright ? 2005 by Grigor'ev, Antipin, Krot, Bessonov. 相似文献
3.
Crystal structure of a double Np(V) and Co(NH3)
6
3+
maleate Co(NH3)6[NpO2(HL)2(H2O)3](HL)2H2O [L = OOC(HC)2COO] was studied. The crystal structure consists of complex anions [NpO2(HL)2(H2O)3]–, HL– anions, [Co(NH3)6]3+ cations, and water molecules of crystallization. Hydrogen bonds in which proton donors are water molecules and hexaamminecobalt cations link structural fragments to form a 3D network. The coordination polyhedra of the Np(V) atoms are pentagonal bipyramids whose equatorial planes are formed by oxygen atoms of two HL– anions and three water molecules. Four crystallographically independent maleate anions were identified in the structure. Two of these anions enter into the Np(V) surrounding, and their coordination capacity is 1.Translated from Radiokhimiya, Vol. 46, No. 6, 2004, pp. 521–523.Original Russian Text Copyright © 2004 by Charushnikova, Krot, Starikova. 相似文献
4.
N. N. Krot A. A. Bessonov M. S. Grigor’ev I. A. Charushnikova V. I. Makarenkov 《Radiochemistry》2004,46(5):421-428
Neptunium(VI) and plutonium(VI) monophthalates were prepared and characterized. The complexes AnO2 (COO)2C6H4 2H2O were isolated from cold solutions, and AnO2 (COO)2C6H4 1.33H2O, from hot solutions. NpO2 (COO)2C6H4 b. 2H2O and PuO2 (COO)2C6H4 2H2O crystalize in the triclinic and monoclinic systems, respectively. The complexes AnO2(COO)2C6H4 1.33H2O are isostructural and crystallize in the rhombohedral system. The thermal behavior of these complexes was studied. Their IR and electronic absorption spectra were recorded. The properties of these complexes were compared to those of known U(VI) monophthalates.Translated from Radiokhimiya, Vol. 46, No. 5, 2004, pp. 389–395.Original Russian Text Copyright © 2004 by Krot, Bessonov, Grigorev, Charushnikova, Makarenkov. 相似文献
5.
The crystal structure of (NpO2)2(OOC)2C6H4·4H2O [rhombic cell: a = 15.937(3), b = 26.922(5), c = 8.020(2) Å, space group Pbcn, Z = 8, V = 3441.0(12) Å3, d
calc = 2.988 g cm-
3, CAD4, MoK
, graphite monochromator, 2934 independent reflections; R
1 = 0.0352, wR
2 = 0.0951] was studied. The structure consists of NpO2
+ cations, H4C6(COO)2
2
- anions, and molecules of coordinated and crystallization water. The crystal lattice involves neutral layers [(NpO2)2(OOC)2C6H4(H2O)3]
n
parallel to the {101} plane. The dioxocations in these layers are bonded to each other to form cationic networks [the Np···Np distance is 3.911(1)-4.202(1) Å]. The coordination polyhedra of Np(1) and Np(2) are pentagonal bipyramids (CN 7). The point group of the neptunyl(V) groups is close to D
h. These groups are bidentate ligands in the cation-cation interaction. The Np = O bond lengths are 1.852(6) [Np(1)-O(1)], 1.849(7) [Np(1)-O(2)], 1.845(7) [Np(2)-O(3)], and 1.841(7) Å [Np(2)-O(4)]; the O = Np = O bond angles are 178.6(3)° [O(2)-Np(1)-O(1)] and 177.4(3)° [O(3)-Np(2)-O(4)]. The equatorial plane of the Np(1) bipyramid consists of two oxygen atoms of adjacent Np(2)O2
+ dioxocations, two water molecules, and a single oxygen atom of the phthalate anion. The equatorial plane of the Np(2) bipyramid consists of two oxygen atoms of adjacent Np(1)O2
+ dioxocations, two oxygen atom of the phthalate anion, and a single water molecule. The bond lengths in the equatorial plane of the bipyramid lie in the following ranges: Np-Oyl 2.373(7)-2.437(7) Å (average 2.397 Å) , Np-Ophth 2.360(7)-2.474(7) Å (average 2.431 Å), and Np-Owater 2.534(8)-2.558(9) Å (average 2.544 Å). The phthalate anions are tridentate bridging ligands binding neptunium atoms only within a single cationic network. 相似文献
6.
According to the data of X-ray diffraction analysis, the structure of LiNpO2CO3·2H2O is built of [LiNpO2CO3H2O]n layers, arranged perpendicularly to the [001] direction, and of crystallization water molecules. The layers are based on mixed cation-anion trigonal networks; Np(V) occurs in the hexagonalbipyramidal environment with three bidentate CO3
2
- ions coordinated in the equatorial plane of the bipyramid. The coordination capacity of anions is 6 and 3 with regard to Np and Li, respectively. 相似文献
7.
8.
An X-ray diffraction study of CsNpO2C2O4 · nH2O was carried out. The structure consists of NpO
2
+
and Cs+ cations, oxalate anions, and water molecules. Dioxo cations are combined by cation-cation interaction into cyclic trimer
in which each NpO
2
+
cation act as monodentate ligand. The coordination polyhedron of the Np(V) atom is a pentagonal bipyramid. The similarity
of the structures of MNpO2C2O4 · nH2O (M = NH4, Cs) based on cyclic trimers combined by oxalate ions into a three-dimensional framework was confirmed.
Original Russian Text I.A. Charushnikova, N.N. Krot, I.N. Polyakova, 2006, published in Radiokhimiya, 2006, Vol. 48, No. 3,
pp. 202–204. 相似文献
9.
10.
Electronic absorption spectra of different crystalline Pu(V) compounds in the range 400–1200 nm were recorded. The correlation between the spectra of these compounds and their structure was discussed. The intensities of the absorption bands of solid compounds with the pentagonal bipyramidal surrounding of the Pu atom are similar to those observed in solution, whereas the centrosymmetrical hexagonal-bipyramidal surrounding is characterized by substantially decreased intensity of the absorption bands up to their complete disappearance. Comparison of the optical spectra of Pu(V) compounds with known structure and those of aqueous Pu(V) solution shows that the hydration number of PuO 2 + is 5. 相似文献