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1.
Chemosphere ; 337: 139321, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37385483

RESUMEN

Amidoxime compounds have been widely used in metal separation and recovery because of their excellent chelating properties to metal ions, especially to uranium (VI). In this study, N, N-bis (2-hydroxyethyl) malonamide was obtained from ethanolamine and dimethyl malonate, and used to prepare a two-dimensional network polymer, then the obtained polymer was immobilized in an environmentally friendly chitosan biomembrane, which enhanced its stability and hydrophobicity, meanwhile the amidoxime functionalization was achieved by oximation reaction of bromoacetonitrile, the application of the material further extends to uranium (VI) separation in solutions. Due to the synergistic action of amide group and amidoxime group, poly (ethanolamine-malonamide) based amidoxime biomembranes (PEA-AOM) showed extraordinary adsorption effect on uranium (VI), among which the saturation adsorption capacity of PEA-AOM-2 was 748.64 mg/g. PEA-AOM-2 also had good reusability (following five cycles of adsorption-desorption, the recovery rate maintained at 88%) and selectivity for uranium (VI), showing satisfactory results in competitive ion coexistence system and simulated seawater experiments. This study demonstrated that PEA-AOM-2 provided a new option for uranium (VI) separation in complex environment and low-concentration uranium background.


Asunto(s)
Polímeros , Uranio , Uranio/análisis , Adsorción
2.
Ying Yong Sheng Tai Xue Bao ; 24(9): 2479-84, 2013 Sep.
Artículo en Chino | MEDLINE | ID: mdl-24417104

RESUMEN

By using fast chlorophyll fluorescence induction dynamics analysis technique (JIP-test), this paper studied the photosynthesis characteristics and fast chlorophyll fluorescence induction dynamics of 1-year old Pistacia chinensis seedlings under the stress of NaCl at the concentrations 0% (CK), 0.15%, 0.3%, 0.45%, and 0.6%. With the increasing concentration of NaCl, the contents of Chl a, Chl b, and Chl (a+b) in the seedlings leaves decreased, the Chl a/b ratio decreased after an initial increase, and the carotenoid content increased. The net photosynthetic rate (P(n)) and stomatal conductance (g(s)) decreased gradually with increasing NaCl concentration. The decrease of P(n) was mainly attributed to the stomatal limitation when the NaCl concentration was lower than 0.3%, and to the non-stomatal limitation when the NaCl concentration was higher than 0.3%. The trapped energy flux per RC (TR0/CS0), electron transport flux per RC (ET0/CS0), density of RCs (RC/CS0), and yield or flux ratio (psi(0) or phi(E0)) decreased, but the absorption flux per CS (ABS/CS0) and the K phase (W(k)) and J phase (V) in the O-J-I-P chlorophyll fluorescence induction curves increased distinctly, indicating that NaCl stress damaged the leaf oxygen-evolving complex (OEC), donor sides, and PS II reaction centers. When the NaCl concentration reached 0.3%, the maximum photochemical efficiency (F(v)/F(m)) and performance index (PI(ABS)) decreased 17.7% and 36.6%, respectively, as compared with the control.


Asunto(s)
Clorofila/fisiología , Fotosíntesis/efectos de los fármacos , Pistacia/fisiología , Cloruro de Sodio/farmacología , Estrés Fisiológico , Fluorescencia , Hojas de la Planta/fisiología
3.
Ying Yong Sheng Tai Xue Bao ; 22(5): 1141-6, 2011 May.
Artículo en Chino | MEDLINE | ID: mdl-21812286

RESUMEN

Taking one-year-old dormant shoots of Pistacia chinensis and Koelreuteria integrifoliola as test materials and the shoots of northern indigenous tree species K. paniculata as the control, the changes of their membrane-lipid peroxidation, antioxidative enzyme activity, and organic osmoregulatory substance content under artificial cooling were studied, aimed to analyze the differences of the three tree species in cold resistance. With the decrease of temperature, the ion leakage percentage of the three tree species increased in S-shape, and the SOD and POD activities decreased after an initial increase. The MDA, soluble protein, and soluble sugar contents of K. integrifoliola and K. paniculata under decreasing temperature decreased after an initial increase, while those of P. chinensis had an increasing trend. The semi-lethal temperature (LT50 ) of K. paniculata, K. integrifoliola, and P. chinensis calculated by the Logistic equation of ion leakage percentage was -27.2 degrees C, -23.7 degrees C, and -27.0 degrees C, respectively. Among the three tree species, K. paniculata had the strongest cold resistance, followed by P. chinensis, and K. integrifoliola.


Asunto(s)
Aclimatación/fisiología , Frío , Pistacia/fisiología , Sapindaceae/fisiología , Árboles/fisiología , China , Árboles/clasificación
4.
Theriogenology ; 76(5): 874-81, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-21664670

RESUMEN

Reproductive performance of 750 adult female Forest musk deer (FMD, Moschus berezovskii) was monitored (from 2005 to 2009) on two Forest musk deer farms in Sichuan province, China. The mean (± SEM) lengths of the estrous cycle, pregnancy, and consecutive fawning intervals were 17.5 ± 0.8 d (n = 64), 182.9 ± 0.8 d (n =190), and 363.2 ± 2.4 d (n = 120), respectively. Copulation occurred from the end of October to early March, with the majority (84.1 ± 1.9%) during November and December (P < 0.05). The fawning rate was 68.7 ± 2.2% in yearling hinds and 73.3 ± 1.3% in adult hinds. Fawning occurred from the end of April to early September, with the majority (88. 9 ± 2.2%) during May and June (P < 0.005), including a peak in May (52.0 ± 1.0%). Yearling hinds fawned later (7.3 ± 1.8 d) than adult hinds. Rates of premature delivery and dystocia were 2.7 ± 0.4 and 2.0 ± 0.3%, respectively. There was a 1.07:1 female-to-male ratio at birth (P > 0.05), with 67.7% twins, but only two cases of triplets and one set of quadruplets among 537 fawns. Birth weight averaged 518.7 ± 10.3 g, ranging from 304 to 775 g (n = 240), with male fawns slightly heavier than females (521.1 ± 14.8 vs 516.9 ± 14.3 g). Postnatal and pre-weaning mortality rates were 25.0 ± 1.2 and 17.9 ± 3.1%, respectively. Postnatal mortality and urinary calculus were much more common in male fawns (P < 0.01). The mortality rate due to suppuration and dyspepsia were different (P < 0.001) between postnatal and pre-weaning periods. Due to higher mortality of male fawns, the adult sex ratio was significantly female-biased. In conclusion, captive FMD had similar seasonal patterns of copulation and fawning as wild FMD and other musk deer species.


Asunto(s)
Ciervos/fisiología , Reproducción/fisiología , Animales , Animales Recién Nacidos/fisiología , Peso al Nacer , China , Copulación , Ciclo Estral/fisiología , Femenino , Masculino , Mortalidad , Complicaciones del Trabajo de Parto/epidemiología , Complicaciones del Trabajo de Parto/veterinaria , Embarazo , Estaciones del Año , Factores Sexuales , Razón de Masculinidad
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