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1.
Rev Sci Instrum ; 93(11): 113201, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36461443

RESUMO

We demonstrate a method to efficiently load a pair of 40Ca+-27Al+ ion crystals with sympathetic cooling and pulsed laser ablation, serving as a starting step for the 27Al+ clock. We achieved a technique to rapidly detect the loading of hot ions by monitoring the 2S1/2 → 2D5/2 narrow transition of 40Ca+ that couples to the shared motional modes between the two ions. The sympathetic cooling time of the 40Ca+-27Al+ ion pair is measured. Two traps are employed to compare the loading time from two directions and it was found that the loading from the axial direction takes much shorter time than loading from the radial direction of the trap. With the help of adaptively controlled trap potential, our method reduced the average loading time of a 40Ca+-27Al+ pair from 26 to 1 min. This research is an important step for increasing the uptime ratio of the 27Al+ optical clock and is useful for other mixed-species ion crystals based on sympathetic cooling.

2.
Opt Express ; 28(8): 11852-11860, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32403687

RESUMO

We present a simple, compact, and efficient scheme for integrated multiple wavelength stabilization and continuous operation of a transportable 40Ca+ optical clock using a multi-channel cavity. The fractional frequency instability of 729 nm clock laser is ∼ 1.5 ×10-15 at 10 s with an approximate linewidth of 1 Hz. Meanwhile, frequency fluctuations of all the other lasers are less than ± 330 kHz/day. The one-day stability of this clock is measured as ∼ 5 ×10-17 through 72 h continuous operation. This scheme is potentially useful for the realization of next-generation transportable optical clocks and other metrological systems.

3.
Eur J Med Chem ; 134: 34-42, 2017 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-28395152

RESUMO

Two types of 2-pyridinecarboxaldehyde thiosemicarbazones Ga(III) complexes, which are 2:1 and 1:1 ligand/Ga(III) complexes, were synthesized and determined by X-ray single crystal diffraction. The antiproliferative activity of these Ga(III) complexes have been examined to illuminate the structure-activity relationships essential to form Ga(III) complexes with remarkable anticancer activity. In addition, Ga(III) complexes where the metal/ligand ratio was 1:1 (C4) had observably higher antiproliferative activity than 1:2 (C3). Ga(III) complexes caused a marked increase of caspase-3 and 9 activity in NCI-H460 cells compared to the metal free ligand. Caspase activation was somewhat mediated by the release of Cyt C from mitochondria after incubation with selected agents. Both types of Ga(III) complexes showed more effective in inhibition of the G1/S transition than the ligand alone.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Gálio/farmacologia , Piridinas/farmacologia , Tiossemicarbazonas/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/química , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Gálio/química , Humanos , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Piridinas/química , Relação Estrutura-Atividade , Tiossemicarbazonas/química
4.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): m809-10, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22719355

RESUMO

In the title complex, [Ni(C(12)H(9)N(2)O(3)S)(2)(H(2)O)(2)]·4H(2)O, the Ni(II) ion is coordinated by four N atoms from two bidentate chelating 4-[(pyridin-2-yl)methyl-idene-amino]-benzene-sulfonate ligands and two O atoms from cis-related water mol-ecules in a slightly distorted octa-hedral environment [Ni-N = 2.071 (3)-2.121 (3) Šand Ni-O = 2.071 (2) and 2.073 (3) Å]. In the crystal, the coordinated water mol-ecules and the four water mol-ecules of solvation are involved in inter-molecular O-H⋯O hydrogen-bonding inter-actions with water and sulfon-ate O-atom acceptors, giving a three-dimensional framework structure.

5.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 9): m1055-6, 2009 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-21577415

RESUMO

The title complex, [Mn(C(12)H(9)N(2)O(3)S)(2)]·2H(2)O, is isotypic with the previously reported Zn(II) and Cd(II) species. The complex was prepared by the reaction of the potassium salt of 2-(2-pyridylmethyl-eneamino)benzene-sulfonic acid with MnCl(2)·6H(2)O in methanol. The complex displays twofold symmetry, with the ligands coordinated in a tridentate meridional-like arrangement through pyridyl N, imine N, and sulfonate O atoms. The metal center has a strongly distorted octa-hedral coordination geometry. The uncoordin-ated water mol-ecules and the complexes participate in a hydrogen-bonding network, forming a two-dimensional structure parallel to the ab plane.

6.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 10): m1200, 2009 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-21577728

RESUMO

In the mononuclear title compound, [Cu(C(12)H(9)N(2)O(3)S)(2)], the copper(II) salt of 2-(2-pyridylmethyl-eneamino)benzene-sulfonic acid, the Cu(II) atom is coordinated by one O and two N atoms from a monoanion as well as by two N atoms from another monoanion in a distorted trigonal-bipyramidal environment.

7.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 11): m1380, 2009 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-21578129

RESUMO

In the mol-ecular structure of the title compound, [CuCl(C(6)H(5)NO)(4)]Cl, the Cu(II) atom is coordinated by four N atoms of four pyridine-4-carboxaldehyde ligands and one chloride anion in a slightly distorted square-pyramidal coordination geometry. There is also a non-coordinating Cl(-) anion in the crystal structure. The Cu(II) atom and both Cl atoms are situated on fourfold rotation axes. A weak C-H⋯Cl inter-action is also present.

8.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 11): m1465, 2009 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-21578190

RESUMO

The title complex, [Co(C(12)H(9)N(2)O(3)S)(2)]·2H(2)O, has site symmetry 2 with the Co(II) cation located on a twofold rotation axis. Two tridentate 2-(2-pyridylmethyl-eneamino)benzene-sulfonate (paba) ligands chelate to the Co(II) cation in a distorted octa-hedral geometry. The pyridine and benzene rings in the paba ligand are oriented at a dihedral angle of 42.86 (13)°. Inter-molecular O-H⋯O and C-H⋯O hydrogen bonding is present in the crystal structure.

9.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 11): m1461, 2008 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-21580899

RESUMO

The title complex, [Cd(Paba)(2)]·2H(2)O or [Cd(C(12)H(9)N(2)O(3)S)(2)]·2H(2)O, was synthesized by the reaction of the potassium salt of 2-(2-pyridylmethyl-eneamino)benzene-sulfonic acid (PabaK) with CdCl(2)·2.5H(2)O in methanol. The Cd(II) atom lies on a crystallographic twofold axis and is coordinated by four N atoms and two O atoms from two deprotonated tridentate 2-(2-pyridylmethyl-eneamino)benzene-sulfonate ligands in a slightly distorted octa-hedral environment. There are extensive hydrogen bonds of the type O-H⋯O between the uncoordinated water molecules and the sulfonate O atoms, through which the complex forms a layered structure parallel to (001).

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 22(5): 738-40, 2002 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-12938416

RESUMO

The polarized atomic beam has found many applications, such as in studying atomic scattering processes, producing polarized nucleus, verifying the parity principle, measuring surface parameters and enriching isotopes. In this paper, we mainly described the experiment of Eu isotope enrichment by means of magnetic deflection. According to the special inner energy level structure of Eu atom, we analyzed the theory of the polarized atomic beam and described the main experimental set-up. Using one coherent laser with the wavelength of 601.9 nm and sigma polarization, Eu153 atoms have been selectively optical pumped and polarized, so positive and negative polarized atomic beams could be produced. The polarized atomic beams have been focused and defocused after passing through the deflection by hex-magnet. Finally, some clear enrichmental signal has been obtained in way of hot-wire detection. During the process of the experiment, we carefully selected the optimized conditions, the Eu153 enrichment effect of 4% can be achieved using only one coherent laser.


Assuntos
Európio/química , Lasers , Elétrons , Polarização de Fluorescência , Isótopos , Magnetismo , Espalhamento de Radiação
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