Study on the biodynamic characteristics and internal vibration behaviors of a seated human body under biomechanical characteristics.

To provide reference and theoretical guidance for establishing human body dynamics models and studying biomechanical vibration behavior, this study aimed to develop and verify a computational model of a three-dimensional seated human body with detailed anatomical structure under complex biomechanical characteristics to investigate dynamic characteristics and internal vibration behaviors of the human body. Fifty modes of a seated human body were extracted by modal method. The intervertebral disc and head motions under uniaxial white noise excitation (between 0 and 20 Hz at 1.

Crystal structure of catena-poly[bis(formato-κO)bis-[μ2-1,1'-(1,4-phenyl-ene)bis-(1H-imidazole)-κ(2) N (3):N (3')]cobalt(II)].

A red block-shaped crystal of the title compound, [Co(HCOO)2(C12H10N4)2] n , was obtained by the reaction of cobalt(II) nitrate hexa-hydrate, formic acid and 1,1'-(1,4-phenyl-ene)bis-(1H-imidazole) (bib) mol-ecules. The asymmetric unit consists of one Co(II) cation, one formate ligand and two halves of a bib ligand. The central Co(II) cation, located on an inversion centre, is coordinated by two carboxyl-ate O atoms and four N atoms from bib ligands, completing an octa-hedral coordination geometry.

Crystal structure of catena-poly[[di-aqua-cobalt(II)]-bis-[μ-5-(4-carb-oxy-ylato-phenyl)picolinato]-κ(3) N,O (2):O (5);κ(3) O (5):N,O (2)-[di-aqua-cobalt(II)]-μ-1-[4-(1H-imidazol-1-yl)phen-yl]-1H-imidazole-κ(2) N (3):N (3')].

The asymmetric unit of the title polymeric Co(II) complex, [Co2(C13H7NO4)2(C12H10N4)(H2O)4] n , contains a Co(II) cation, a 5-(4-carboxyl-atophen-yl)picolinate dianion, two coordination water mol-ecules and half of 1-[4-(1H-imidazol-1-yl)phen-yl]-1H-imidazole ligand. The Co(II) cation is coordinated by two picolinate dianions, two water mol-ecules and one 1-[4-(1H-imidazol-1-yl)phen-yl]-1H-imidazole mol-ecule in a distorted N2O4 octa-hedral coordination geometry. The two picolinate dianions are related by an inversion centre and link two Co(II) cations, forming a binuclear unit, which is further bridged by the imidazole mol-ecules, located about an inversion centre, into the polymeric chain propagating along the [-1-11] direction.

4-Carboxy-pyridinium 3-carb-oxy-4-hydroxy-benzene-sulfonate.

Cocrystallization of 4-carboxy-pyridine (4-CPY) and 5-sulfosalicylic acid (5-H(2)SSA) yields the title salt, C(6)H(6)NO(2) (+)·C(7)H(5)O(6)S(-). In the crystal structure, the components of the salt are linked by a combination of inter-molecular O-H⋯O and N-H⋯O, and weak C-H⋯O hydrogen bonds, forming a three-dimensional framework.

Three-dimensional network in piper-azine-1,4-diium-picrate-piperazine (1/2/1).

In the title compound, C(4)H(12)N(2) (2+)·2C(6)H(2)N(3)O(7) (-)·C(4)H(10)N(2), the piperazine-1,4-diium cations and piperazine mol-ecules lie on crystallographic inversion centres. In the crystal structure, inter-molecular N-H⋯O and N-H⋯N hydrogen bonds link the components to form two-dimensional layers parallel to the (001) plane. These layers are, in turn, connected by weak inter-molecular C-H⋯O hydrogen bonds and π-π stacking inter-actions [centroid-centroid distance between parallel aryl rings = 3.