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1.
Dalton Trans ; 48(46): 17321-17330, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31723948

RESUMO

Surface modification of carbon materials is an important issue for its potential application. In this work, this purpose has been successfully achieved by the incorporation of polydopamine (PDA) and phosphomolybdic acid (PMA), forming carbon/PDA/PMA hybrid electrode materials, in which PDA acts both as a linker molecule and as a pseudo-capacitance provider, and PMA contributes to pseudo-capacitive performance. It is revealed that adding PDA and/or PMA results in a decrease of porosity but in an increase of electrical conductivity and thus a suitable combination of porosity, conductivity, and pseudo-capacitance is vital for achieving the optimization of capacitive performance. By using the Trasatti method, we found out that increasing PDA or PMA results in the improvement of pseudo-capacitance proportion and the C-PDA/PMA-1 : 1 sample exhibits a pseudo-capacitance proportion of 32%. In a two-electrode configuration, the C-PDA/PMA-1 : 1 sample delivers a specific capacitance of 101 F g-1 at 1 A g-1, a cycling performance of 108% within 10 000 cycles, and an energy density of 3.5 W h kg-1 (nearly 3.2 times that of the C-blank sample) at 500 W kg-1. Moreover, the dual surface modification of PDA and PMA could be extended to other energy storage systems, highly improving capacitive performance by the synergic effect.

2.
Dalton Trans ; 46(47): 16493-16504, 2017 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-29148553

RESUMO

The reaction of 2-hydroxyl-4-carboxylbenzenesulfonic acid (H3L) and rare earth (RE) metal nitrates together with two N-heterocyclic ligands gives rise to the formation of 38 complexes, namely, [La(H2L)2(ox)0.5(H2O)4]n·2nH2O (1-La) (ox = oxalate), [RE2(H2L)2 (ox)(H2O)12]·2(H2L)·8H2O (2-RE) (RE = Nd, Sm, Eu, Gd, Tb, Dy), [RE(SO4)(H2O)7]·(H2L)·3H2O (3-RE) (RE = Ho, Er, Tm, Yb, Lu and Y), [RE(L)(H2O)3]n·nH2O (4-RE) (RE = Er, Tm, Yb and Lu), [RE(L)(2,2'-bipy)(H2O)]n (5-RE) (RE = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho and Y, 2,2'-bipy = 2,2'-bipyridine), [RE(L)(1,10-phen)(H2O)]n (6-RE) (RE = La, Pr, Nd, Sm, Eu, 1,10-phen = 1,10-phenanthroline), and [RE(L')(1,10-phen)2(H2O)]n (7-RE) (RE = Gd, Tb, Ho, Er, Yb and Lu, H3L' = 2-hydroxy-3-nitro-4-carboxybenzenesulfonic acid), which have been characterized by elemental analysis, IR, TG, PL, powder and single-crystal X-ray diffraction. Complexes 1-La, 2-RE and 3-RE present zigzag chain, di- and mono-nuclear structures, in which H2L- acts as a counterion and monodentate and µ2-bridging monoanions. For the three species, light RE metal cations tend to induce the formation of oxalate while heavy RE metal cations tend to induce the formation of sulfate. Complexes 4-RE and 5-RE exhibit layer structures incorporating helical chains, in which the L3- trianion presents µ3 and µ4 coordination modes. Complexes 6-RE containing light RE metal cations show layer structures incorporating helical chains, while complexes 7-RE containing heavy RE metal cations have helical chain structures supported by the bridging of in situ generated L'3-. Remarkably, the in situ generated oxalates in 1-La and 2-RE, as well as the in situ generated L'3- in 7-RE, also play a crucial role in determining the structures of these complexes. Structure evolutions make these complexes present various luminescent emissions. Complexes 3-Tm, 3-Yb, 3-Lu, 3-Y and 4-Lu exhibit ultraviolet emissions from 354 to 370 nm. Complexes 1-La and 6-La present blue emissions at 442 and 463 nm. Complexes 2-Eu, 2-Tb, 5-Tb and 7-Tb exhibit characteristic red and green emissions while the complex 5-Y presents a green emission at 501 nm. Meanwhile, complexes 2-Nd, 3-Yb, 4-Yb, 5-Nd, 6-Nd, and 7-Yb show near-infrared (NIR) emissions. Moreover, 2-Eu, 2-Tb, 5-Tb, 7-Tb and 5-Y show longer luminescence lifetimes from 390.47 to 1211.57 µs.

3.
Dalton Trans ; 44(12): 5837-47, 2015 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-25715731

RESUMO

Reaction of AgX (X = NO3− and ClO4−) and three flexible bis(pyridyl) ligands with a chelating spacer leads to the formation of eight novel Ag(I)-bis(pyridyl) coordination complexes: {[Ag2L1(NO3)2]n·2nH2O} (1), {[AgL1]n·nClO4} (2), {[AgL2]n·nNO3} (3), {[AgL2]n·nClO4} (4), [Ag2(H2L2)2]·6ClO4·9H2O (5), {[AgL3]n·nNO3·nH2O} (6), {[AgL3]n·nClO4·nH2O} (7), and {[Ag3(L3)2(ClO4)]n·2nClO4} (8) (L1 = N,N'-bis(pyridin-2-ylmethyl)propane-1,3-diamine, L2 = N,N'-bis(pyridin-3-ylmethyl)propane-1,3-diamine, L3 = N,N'-bis(pyridin-4-ylmethyl)propane-1,3-diamine), which have been characterized by elemental analysis, IR, TG, UV-Vis DRS, PL, powder and single-crystal X-ray diffraction. Complex 1 presents a (4,4) layered motif which is furnished by the bridging of L1 molecules and nitrate anions in µ4 (κ1N1:κ1N2:κ1N3:κ1N4) and µ2 (κ1O4:κ1O6) modes. With a different µ2 (κ1N1:κ1N2:κ1N3:κ1N4) mode, L1 molecules in complex 2 join the adjacent Ag(I) cations to form a helical chain structure. Complexes 3 and 4 also show helical chain structures with the L2 molecules displaying the same µ3 (κ1N1:κ1N2:κ1N3:κ1N4) mode. The protonation of ­NH­ groups in the chelating spacer leads to the formation of H2L22+ cations which further results in a macrocyclic dinuclear motif in complex 5. Complexes 6 and 7 are 3-D svi-x nets with the counter-anions and lattice water molecules being encapsulated in the 1-D channels. Complex 8 exhibits a snake-shaped chain with the L3 molecules presenting µ3 (κ1N:κ1N':κ1N″:κ1N) mode. The structural diversities of complexes 1­8 can be attributed to the coordination modes and conformations of L1­L3. The photoluminescence properties demonstrate that complexes 1, 2 and 5 exhibit ligand-based blue emission maxima from 455 to 462 nm at room temperature in the solid state.


Assuntos
2,2'-Dipiridil/química , Quelantes/química , Complexos de Coordenação/química , Substâncias Luminescentes/química , Compostos Macrocíclicos/química , Prata/química , 2,2'-Dipiridil/síntese química , Quelantes/síntese química , Complexos de Coordenação/síntese química , Ligantes , Substâncias Luminescentes/síntese química , Compostos Macrocíclicos/síntese química , Modelos Moleculares
4.
Chinese Journal of Pediatrics ; (12): 944-947, 2012.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-348499

RESUMO

<p><b>OBJECTIVE</b>To investigate the clinical features and molecular diagnostic methods of three patients with DiGeorge anomaly.</p><p><b>METHOD</b>The clinical manifestations and immunological features of the three cases with DiGeorge anomaly were analyzed. We detected the chromosome 22q11.2 gene deletion by fluorescence in situ hybridization (FISH).</p><p><b>RESULT</b>(1) CLINICAL MANIFESTATIONS: All three cases had varying degrees of infection, congenital heart disease and small thymus by imaging; two cases had significant hypocalcemia (1.11 mmol/L and 1.22 mmol/L, respectively), accompanied by convulsions; only 1 case had cleft palate and all had no significant facial deformity. (2) Immunological characteristics: All three cases had varying degrees of T-cell immune function defects (percentage of T lymphocytes was 24% - 43%, absolute count was 309 - 803/µl), and levels of immunoglobulin G, A, M, and percent of B lymphocytes and absolute count were normal. (3) Detection of the chromosome 22q11.2 gene deletion: 400 cells of each case were detected. All cells showed two green and one red hybridization signal, indicating the presence of gene deletions in chromosome 22q11.2. (4) OUTCOME: All three cases were treated with thymosin, and appropriate clinical intervention for cardiac malformations, hypocalcemia, and were followed-up for 4 - 18 months, the prognosis was good.</p><p><b>CONCLUSION</b>DiGeorge anomaly showed diverse clinical manifestations. We should consider the disease if patients had congenital heart disease, thymic hypoplasia, hypocalcemia and/or impaired immune function. FISH for detecting chromosome 22q11.2 gene deletion can be used as accurate and rapid diagnostic method. Thymosin treatment and other clinical intervention may help to improve the prognosis of patients with partial DiGeorge anomaly.</p>


Assuntos
Feminino , Humanos , Recém-Nascido , Masculino , Células Cultivadas , Deleção Cromossômica , Cromossomos Humanos Par 22 , Genética , Síndrome de DiGeorge , Diagnóstico , Genética , Alergia e Imunologia , Cardiopatias Congênitas , Diagnóstico , Genética , Hipocalcemia , Diagnóstico , Genética , Hibridização in Situ Fluorescente , Linfócitos T , Alergia e Imunologia , Timo , Alergia e Imunologia , Patologia
5.
Ying Yong Sheng Tai Xue Bao ; 22(1): 66-72, 2011 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-21548290

RESUMO

Taking cold-tolerant rice cultivar 996 and cold-sensitive rice cultivar 4628 as test materials, a growth chamber experiment was conducted to investigate their pollen characters and flag leaf physiological and biochemical characteristics under the effects of low temperature stress. The plants were respectively treated with low temperature [ 19 degrees C (06:00-8:00; 19:00-23:00 )/21 degrees C (08:00-10:00; 16:00-19:00)/23 degrees C (10:00-16:00)/17 degrees C (23:00-06:00)] and optimal temperature [24 degrees C (06:00-8:00; 19:00-23:00)/26 degrees C (08:00-10:00; 16:00-19:00)/30 degrees C (10:00-16:00)/22 degrees C (23:00-06:00)] for seven days after heading. Low temperature stress decreased the anther dehiscence coefficient and pollen germination rate, as well as the sterile pollen rate of spikelets on middle and lower parts of panicles, with the anther dehiscence coefficient and pollen germination rate of cultivar 996 being significantly higher than those of cultivar 4628, indicating that cold-tolerant cultivar 996 had the capability to keep better pollination and pollen germination. Under low temperature stress, the flag leaf soluble protein and free proline contents and their increments of cultivar 996 were significantly higher than those of cultivar 4628, while the MDA content and relative conductivity and their increment were in adverse, indicating that cold-tolerant cultivar 996 had more quick and strong protective responses, and was able to keep stable membrane structure and function.


Assuntos
Temperatura Baixa , Flores/fisiologia , Oryza/fisiologia , Folhas de Planta/fisiologia , Pólen/metabolismo , Adaptação Fisiológica , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Estresse Fisiológico
6.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 7): o1331, 2008 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-21202955

RESUMO

The asymmetric unit of the title compound, C(19)H(12)N(4)O·H(2)O, contains one organic molecule and one solvent water mol-ecule, which are connected by N-H⋯O and O-H⋯N hydrogen bonds. In addition, there is one intra-molecular O-H⋯N hydrogen bond. The organic mol-ecule is essentially planar (r.m.s. deviation for all non-H atoms = 0.028 Å).

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