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1

Altitude Patterns of Leaf Carbon Isotope Composition in a Subtropical Monsoon Forest

Pan S., Zhang W., Zhao M., Li Y., Xu S., Wang G.

Polish Journal of Ecology

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2016

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Vol. 64, nr 2

178--188

EN

Leaf carbon isotope composition (δ13C) of both vascular and non-vascular plants were investigated in order to assess their variability along an altitude gradient (414, 620, 850, 1086,1286 and 1462 m) from a subtropical monsoon forest located at Mt. Tianmu Reserve, eastern China. Leaf δ13C values of all plant species ranged from -34.4 to -26.6‰, with an average of -29.8‰. There is no significant difference in leaf δ13C between vascular plants and mosses, however, trees had significantly higher δ13C values than herbs. For pooled data, leaf δ13C was positively correlated with altitude. Leaf δ13C was significantly and negatively correlated with annual mean temperature and atmospheric pressure, while it was significantly and positively correlated with soil water content. Furthermore, there was no relationship between leaf δ13C and soil nitrogen content or soil phosphorus content. The altitudinal trend in leaf δ13C is the consequence of the interaction between temperature, atmospheric pressure and soil water content.

2

Altitude Patterns of Leaf Carbon Isotope Composition in a Subtropical Monsoon Forest

Pan S., Zhang W., Zhao M., Li Y., Xu S., Wang G.

Polish Journal of Ecology

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2015

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Vol. 63, nr 4

512--522

EN

Leaf carbon isotope composition (δ13C) of both vascular and non-vascular plants were investigated in order to assess their variability along an altitude gradient (414, 620, 850, 1086, 1286 and 1462 m) from a subtropical monsoon forest located at Mt. Tianmu Reserve, eastern China. Leaf δ13C values of all plant species ranged from -34.4 to -26.6‰, with an average of -29.8‰. There is no significant difference in leaf δ13C between vascular plants and mosses, however, trees had significantly higher δ13C values than herbs. For pooled data, leaf δ13C was positively correlated with altitude. Leaf δ13C was significantly and negatively correlated with annual mean temperature and atmospheric pressure, while it was significantly and positively correlated with soil water content. Furthermore, there was no relationship between leaf δ13C and soil nitrogen content or soil phosphorus content. The altitudinal trend in leaf δ13C is the consequence of the interaction between temperature, atmospheric pressure and soil water content.

3

Wzrost i właściwości optyczne kryształu BaGd2 (MoO4)4 domieszkowanego Er3+

Han S., Wang J., Zhang H., Pan S., Xv H., Wang Y., Shen C.

Chemik

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2013

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Vol. 67, nr 9

763--770

PL

Pojedynczy kryształ BaGd2(MoO4)4 domieszkowany 1% at. Er3+ wyhodowano metodą Czochralskiego. Omówiono szczegóły procedury otrzymywania i wzrostu kryształu. Kryształ ma doskonałą płaszczyznę poślizgu (010), a jego łupliwość czyni go przydatnym jako ośrodek czynny w mikrolaserach. Zmierzono widmo absorpcyjne w zakresie światła widzialnego i bliskiej podczerwieni (NIR) w temperaturze pokojowej. W zakresie od 380 do 1600 nm występuje kilka intensywnych pików absorpcyjnych. Zmierzono również widmo fluorescencyjne wzbudzane za pomocą lampy ksenonowej. Zaobserwowano intensywny pik emisyjny NIR 1536 nm. Czasy trwania fluorescencji 4I13/2 oraz 4I11/2 wyznaczone za pomocą dopasowania krzywej wykładniczej wyniosły odpowiednio 5,85 ms i 112,62 μs. Ciepło właściw Er3+ BaGd2(MoO4)4 w 25°C wynosi 0,471 J g-1 K-1. Na podstawie zmierzonych widm obliczono parametry optyczne na podstawie teorii Judda-Ofelta (J–O).

EN

A 1 at % Er3+ doped BaGd2(MoO4)4 single crystal was grown by the Czochralski method. Details on the preparation and growth procedures were discussed. The crystal has a perfect (010) cleavage plane, and the cleavage character makes the crystal suitable as a gain medium for microchip lasers. The absorption spectrum in the visible and near-infrared (NIR) regions was measured at room temperature. There are several strong absorption peaks in the range from 380 to 1600 nm. The fluorescence spectrum excited by a Xenon lamp was also measured. A strong NIR emission peak located at 1536 nm was observed. The fluorescence lifetimes of 4I13/2 and 4I11/23+:BaGd2(MoO4)4 at 25°C is 0.471 J g-1 K-1. Using the measured spectra, the optical parameters were calculated using the J–O theory.

4

Stability of nominally stable uncertain singularly perturbed systems with multiple time delays

Chen C., Pan S., Hsieh J.

Control and Cybernetics

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2002

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Vol. 31, no 1

5-16

EN

In this paper, the robust asymptotic stability problem for a class of nominally stable uncertain singularly perturbed systems with multiple non-commensurate time delays is considered. A delay-dependent criterion is first proposed in this paper to guarantee robust asymptotic stability of the system under consideration. Based on this result, the range of allowable bounds of the perturbation matrices preserving the closed-loop stability can easily be found. Moreower, a simple criterion is also proposed to guarantee asymptotic, stability of the nominal system. Furthermore, a simple estimation of the stability bound epsilon* is proposed such that the nominal system is asymptotically stable for epsilon [belongs to](0,epsilon*). It can be seen that the stability bound proposed in this paper is less conservative than that presented in recent research. Finally, a numerical example is provided to illustrate our main results.

5

D-stability for a class of discrete descriptor systems with multiple time delays

Pan S., Chen C., Hsieh J.

Control and Cybernetics

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2002

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Vol. 31, no 1

79-89

EN

In this paper, the research on discrete descriptor systems is extended to include discrete multiple time-delay descriptor systems. The impulse-free and D-stability problem for a class of discrete descriptor systems with multiple time delays is investigated. A delay-dependent criterion is first derived to guarantee that the system is proper. A delay-dependent stability criterion in terms of spectral radius is then presented to ensure the D-stability of the system. Furthermore, a delay-dependent criterion is proposed to guarantee that the system is nebular, impulse-free, and D-stable. Finally, a numerical example is provided to illustrate our main results.