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1.
Ying Yong Sheng Tai Xue Bao ; 27(4): 1177-1188, 2016 Apr 22.
Artículo en Chino | MEDLINE | ID: mdl-29732774

RESUMEN

The objective of the present study was to examine the adaptation strategy of Amorphophallus xiei, a shade-demanding species, grown under different levels of light intensity. The responses of leaf to photosynthetic active radiation, CO2 and simulated sunflecks were analyzed in A. xiei grown under 100% (high light), 32.6% (moderate light) and 5.98% (low light) of full sun. Meanwhile, chlorophyll a fluorescence parameter and light energy partitioning were also recorded and calculated in the above-mentioned responsive process. The results showed that in most cases, the maximum photosynthetic rate (Pmax), dark respiration rate, apparent quantum yield and carboxylation efficiency in A. xiei significantly decreased with increasing the light level, however, the light compensation point, CO2 compensation point significantly increased. The photosynthetic induction was quicker in individuals grown under moderate light (P<0.05), and the initial stomatal conductance (gs-i) during dark adaptation increased significantly with increasing the light level. There was a ne-gative correlation between gs-i and the time required to reach 30%, 50% and 90% of Pmax during the process of photosynthetic induction. Moreover, the values of actual photochemical efficiency of PS2 (ΔF/Fm') in the light, phototochemical quenching of chlorophyll fluorescence (qP) and photosynthetic electron transport rate (ETR) were higher and non-photochemical quenching (NPQ) recorded in photosynthetic induction was also higher in individuals grown under high light, nevertheless, the maximum photochemical efficiency of PS2 in the light (Fv'/Fm') was higher in individuals grown under low light. The proportion of light energy allocated to non-photochemical quenching (ФNPQ) was lower in individuals grown under high light, and, correspondingly, it was higher in ones grown under low light. The results obtained here suggested that, when exposed to high light stress, moderate- and low-light-grown A. xiei would activate the mechanism of energy dissipation to protect itself from injury. Correspondingly, high-light-grown individuals would employ the strategy of increasing heat dissipation and forming quenching complex to cope with high light stress, which, however, might be one of reasons for the sensitivity of A. xiei to high light environment.


Asunto(s)
Amorphophallus/fisiología , Fotosíntesis , Luz Solar , Aclimatación , Amorphophallus/efectos de la radiación , Clorofila/fisiología , Clorofila A , Transporte de Electrón , Fluorescencia , Hojas de la Planta/fisiología , Hojas de la Planta/efectos de la radiación
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(1): 96-8, 2012 Jan.
Artículo en Chino | MEDLINE | ID: mdl-22497136

RESUMEN

Polyvinyl alcohol (PVA), polyethylene (PE) and ethylene-vinyl acetate copolymer (EVA) film was prepared. The optic capability, infrared transmittance and heat preservation capability of the films were studied respectively. The result indicated that the haze degree of the PVA film decreased about 15% and 12% than PE film and EVA film; PVA film transmittance of IR was more or less than other films in the 7-14 microm wavelength range so that the temperature of greenhouse could be increased effectively in daylight. It was just 16.2% about 20% less than EVA film, and 50% less than PE film. The PVA film could be used as agricultural film in greenhouse to promote heat preservation performance greatly.

3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(6): 1518-20, 2011 Jun.
Artículo en Chino | MEDLINE | ID: mdl-21847923

RESUMEN

EVOH, PE and EVA films were prepared by extrusive blowing techniques, the optic capability, transmittance, haze, infrared anti-transmittance and heat preservation of the films were studied by IR spectroscopy and optic block. The result indicated that the haze degree of the EVOH film decreased about 10% and 5% compared to PE film and EVA film respectively, EVOH film's transmission of IR is much less than other films in the 2.5-25 microm wavelength range, it is just 9.03% in 7-14 microm wavelength range, and about 27% less than EVA film, while much less than PE film. It was found that EVOH film has much better capability of infrared anti-transmittance and point-blank light transmission than other two kinds of films. It was good for calefaction and heat preservation of greenhouse.

4.
Inorg Chem ; 49(13): 5868-75, 2010 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-20518473

RESUMEN

Three novel Mn(III) polymers, [Mn(phox)(2)(N(3))](n) (1), [Mn(Etphox)(2)(N(3))](n) (2), and [Mn(Etphox)(2)(C(2)N(3))](n) (3), using achiral ligand Hphox (Hphox = 2-(4,5-dihydrooxazol-2-yl)phenol) and chiral ligand HEtphox (HEtphox = 2-(4-ethyl-4,5-dihydrooxazol-2-yl)phenol) were synthesized and structurally and magnetically characterized. All complexes are of 1D chain structures and form 2D frameworks by weak interactions. The adjacent 1D chains of complex 1 are connected by face-to-face pi-pi interactions, C-H...pi interactions, and hydrogen bonding, which leads to the formation of a supramolecular 2D sheet structure. The three compounds show antiferromagnetic coupling between Mn(III) ions. And compound 2 is a spin-canted weak ferromagnet with T(N) = 5.6 K, showing metamagnetic behavior with a two-step magnetic phase transition.

5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 44(2): 154-6, 2010 Feb.
Artículo en Chino | MEDLINE | ID: mdl-20388338

RESUMEN

OBJECTIVE: To evaluate the safety and immunogenicity of the Bilive(TM) combined hepatitis A and hepatitis B vaccine in healthy children. METHODS: A total of 116 healthy children aged 1 - 10 years, who, without history of hepatitis A vaccine vaccination and anti-HAV negative, had completed the full immunization of hepatitis B vaccine were recruited in city of Changzhou in Jiangsu province. The Bilive(TM) combined hepatitis A and hepatitis B vaccine was administered according to a two-dose schedule (0, 6 months). The dosage was 250 U for hepatitis A antigen and 5 microg for hepatitis B surface antigen. The potential adverse effects were observed within 72 hours after vaccination. The serum samples were collected for the testing of anti-HAV and anti-HBs at month 1, 6 and 7 after initial dose. RESULTS: The local and systemic adverse reactions after immunization were slight and temporary. The rates of local and systemic adverse reactions were 12.1% (14/116) and 6.0% (7/116). The sero-conversion rates of HAV were from 92.9% (92/99) to 100.0% (101/101) and the geometric mean titers (GMT) ranged from 47.0 mIU/ml to 2762.3 mIU/ml 1, 6, 7 months after initial dose. The sero-protection rate of HBV was 86.1% (87/101) before vaccination and came up to 100.0% (101/101) one month after initial dose, and the GMTs of HBV were from 894.3 mIU/ml to 3314.3 mIU/ml 1, 6, 7 months after initial dose. CONCLUSION: The Bilive(TM) combined hepatitis A and hepatitis B vaccine has good safety and immunogenicity in healthy children who had preexisting immunity to hepatitis B virus.


Asunto(s)
Vacunas contra la Hepatitis A/inmunología , Vacunas contra Hepatitis B/inmunología , Niño , Preescolar , Relación Dosis-Respuesta Inmunológica , Femenino , Vacunas contra la Hepatitis A/efectos adversos , Vacunas contra Hepatitis B/efectos adversos , Humanos , Esquemas de Inmunización , Lactante , Masculino , Vacunas Combinadas/efectos adversos , Vacunas Combinadas/inmunología
6.
J Mol Model ; 15(11): 1329-36, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19387705

RESUMEN

The equilibrium geometries, total energies, and vibrational frequencies of anions X(2)Y(2)(-) (X = C, Si, Ge and Y = N, P, As) are theoretically investigated with density functional theory (DFT) method. Our calculation shows that for C(2)N(2)(-) species, the D(2h) isomer is the most stable four-membered structure, and for other species the C(2v) isomer in which two X atoms are contrapuntal is the most stable structure at the B3LYP/6-311 +G(*) level. Wiberg bond index (WBI) and negative nucleus-independent chemical shift (NICS) value indicate the existence of delocalization in stable X(2)Y(2)(-) structures. A detailed molecular orbital (MO) analysis further reveals that stable isomers of these species have strongly aromatic character, which strengthens the structural stability and makes them closely connected with the concept of aromaticity.


Asunto(s)
Aniones/química , Elementos Químicos , Isomerismo , Modelos Moleculares , Vibración
7.
Zhonghua Liu Xing Bing Xue Za Zhi ; 29(6): 556-9, 2008 Jun.
Artículo en Chino | MEDLINE | ID: mdl-19040036

RESUMEN

OBJECTIVE: To evaluate the immunogenicity, safety, stability and consistency of three consecutive lots of an inactivated hepatitis A vaccine (Healive). METHODS: A double-blind, randomized and controlled clinical trial was conducted in healthy volunteers aged from 1 to 8 years. Totally, 400 subjects were enrolled and assigned into four groups, each receiving one of the three lots of Healive or a licensed control vaccine in 0 and 6th month. Safety was assessed through a 30 minutes and three days observation, thereafter. Anti-HAV titers were determined on the 1st, 6th and 7th month after the vaccination. RESULTS: Seroconversion rate of four groups were all 100% by the end of the schedule while GMTs of Healive were 3237.06-3814.14 mIU/ml but were not significantly different. GMT of control vaccine was 1467.49 mIU/ml. Healive and control vaccine were well tolerated with 1%-5% incidence of overall adverse reactions in which most of them were mild and moderate. No severe adverse reaction was reported. CONCLUSION: The three consecutive lots of Healive were well consistent as indicated by immunogenicity and safety while immunogenicity was better than the vaccine used as control.


Asunto(s)
Vacunas contra la Hepatitis A/inmunología , Hepatitis A/prevención & control , Niño , Preescolar , Método Doble Ciego , Femenino , Vacunas contra la Hepatitis A/efectos adversos , Humanos , Lactante , Masculino , Control de Calidad
8.
Vaccine ; 26(18): 2297-301, 2008 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-18395305

RESUMEN

Immunization is considered as the most effective way for the prophylaxis of hepatitis A virus (HAV) infection. This study aimed to evaluate the immunogenicity and safety of three consecutive lots of a new preservative-free inactivated hepatitis A vaccine (Healive) in healthy children. A double-blind, randomized and controlled clinical trial was conducted in healthy volunteers aged from 1 to 8 years. Total 400 subjects were enrolled and assigned into four groups, receiving one of the three lots of Healive or an established control vaccine. The vaccination was two-dose regimen with 6 months apart. Anti-HAV titers were determined at the 1st, 6th and 7th month. The results showed that Healive was highly immunogenic in children with 100% seroconversion rate (SR) and 3237-3814 mIU/ml geometry mean titer (GMT) 1 month after the second dose. The immunogenicity of Healive was statistically higher than that of the control vaccine with respect to GMT and SR (P=0.037 to P<0.001). Both Healive and control vaccine were well tolerated with 1-5% incidence of overall adverse reactions (P>0.298). Severe adverse reaction was not reported. Both SRs (1, 6 and 7 months) and GMTs (1 and 7 months) in subjects receiving one of the three consecutive lots of Healive had not statistical difference (P=0.114-0.710), suggesting that Healive was well consistent. The immune responses in younger children (1-3 years) and older children (4-8 years) were similar to each other (P=0.187-0.963). The present study indicated that Healive was greatly consistent between production lots, well tolerated and highly immunogenic in children, which made the preservative-free inactivated hepatitis A vaccine well suitable for inclusion in the routine programme of children vaccination.


Asunto(s)
Vacunas contra la Hepatitis A/efectos adversos , Vacunas contra la Hepatitis A/inmunología , Niño , Preescolar , Método Doble Ciego , Femenino , Hepatitis A/prevención & control , Anticuerpos de Hepatitis A/sangre , Vacunas contra la Hepatitis A/normas , Humanos , Inmunización Secundaria , Lactante , Masculino , Vacunas de Productos Inactivados/efectos adversos , Vacunas de Productos Inactivados/inmunología , Vacunas de Productos Inactivados/normas
9.
Huan Jing Ke Xue ; 28(2): 289-94, 2007 Feb.
Artículo en Chino | MEDLINE | ID: mdl-17489185

RESUMEN

Nanometer particles composed of manganese oxides (Nano-MnO(x)), which prepared by rheological phase reaction method, show superior low-temperature SCR activity for NO with NH3 in the presence of excess O2. In experiments, the NO conversion is 98.25% at 80 degrees C, and nearly 100% NO could be converted in 100 - 150 degrees C. Due to the reason of competing adsorption, H2O has a slight impact on the activity and the deactivation of SO2 is reversible. The experiments implied that the superior low-temperature catalytic activity of Nano-MnO(x) was mainly due to its high BET specific areas and poor crystallinity.


Asunto(s)
Amoníaco/química , Compuestos de Manganeso/química , Nanopartículas del Metal/química , Óxido Nítrico/química , Óxidos/química , Catálisis , Frío , Oxidación-Reducción
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(3): 496-8, 2006 Mar.
Artículo en Chino | MEDLINE | ID: mdl-16830764

RESUMEN

A new fluorescent functional monomer DMAAN has been designed and synthesized for the first time. The monomer was expected to bind with cytosine via complementary hydrogen bonding under certain experimental conditions. The synthetic procedure of DMAAN is as follows. A suspension of 2,6-diaminopyridine in phosphoric acid was added to acetylacetone. The mixture was warmed for thirty minutes on a steam-bath. Then 2,4-dimethyl-7-amino-1,8-naphthyridine(DMAN, mp 216-218 degrees C) was obtained. DMAAN was prepared by the reaction of DMAN with acryloyl chloride in chloroform and triethylether mixed solvent. Acryloyl chloride in anhydrous chloroform was added dropwise over 30 minutes with constant stirring at 4 degrees C. The melting point of the final product was 239-241 degrees C. Mass spectrometry and proton NMR were used to confirm the chemical structure of DMAN and DMAAN. The products were also characterized by UV and fluorescence spectrometry.

11.
Huan Jing Ke Xue ; 26(4): 143-6, 2005 Jul.
Artículo en Chino | MEDLINE | ID: mdl-16212185

RESUMEN

Removal of three water-soluble dyes through biosorption of four fungal strains was investigated. Some key factors affecting the formation of pellets and removal of dye under opening conditions was examined and the possibility of repeated inoculation of pellets was evaluated. The results show that removal of acid brilliant red B by 4 strains was almost 100%; the removal of all three tested dyes by Trichoderma sp. was more than 99%. Trichoderma sp. formed pellets well under opening conditions when its fragmentized mycelium obtained by 3 min grinding pellets at high concentration was inoculated, as 100% removal of acid brilliant red B was achieved by biosorption of newly growing pellets. Repeated inoculation of pellets accelerated dye removal, time for 100% decolorization reduced from first inoculation 72h to third inoculation 12h.


Asunto(s)
Colorantes/metabolismo , Hongos/metabolismo , Residuos Industriales/análisis , Micelio/crecimiento & desarrollo , Eliminación de Residuos Líquidos/métodos , Aspergillus/metabolismo , Biodegradación Ambiental , Hongos/crecimiento & desarrollo , Phanerochaete/metabolismo , Rhizopus/metabolismo
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