Showing papers by "Xiamen University published in 1987"
TL;DR: In this article, the authors investigated the promoter action of rare earth oxides (REO) in Rh/SiO 2 catalysts for syngas conversion to ethanol and the characterization of these catalysts by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM).
57 citations
TL;DR: The major concentrating step in the food web was Se incorporation by phytoplankton and zooplankon, up to four orders of magnitude above ambient seawater concentrations.
33 citations
TL;DR: In this paper, a uniform and flexible polyparaphenylene (PPP) film was obtained by electrochemical polymerization of benzene in concentrated sulphuric acid with an anhydrous Lewis acid as catalyst.
25 citations
TL;DR: In this article, practical stability of discontinuous large-scale systems with various decomposition forms is discussed, and some applied criteria, which are easy to apply, are obtained and proved.
Abstract: Practical stability is neither weaker nor stronger than Lyapunov stability, and practical stability of discontinuous large-scale systems has been rarely studied to date. In this paper practical stability of discontinuous large-scale systems with various decomposition forms is discussed, and some applied criteria, which are easy to apply, are obtained and proved.
6 citations
TL;DR: The in vitro effects of steroids, human chorionic gonadotropin (HCG) and cyanoketone on germinal vesicle breakdown (GVBD) of striped mullet oocytes suggest that Δ5 (pregnenolone derived) and Δ4 steroids may be involved in final oocyte maturation in this species.
Abstract: The in vitro effects of steroids, human chorionic gonadotropin (HCG) and cyanoketone on germinal vesicle breakdown (GVBD) of striped mullet (Mugil cephalus L.) oocytes were investigated. All concentrations of HCG (5,10,50 I.U./ml), progesterone and pregnenolone at the highest concentrations(lug/ml) were moderately effective in inducing GVBD, whereas 17β-estrodiol, cortisol, testosterone, 11β-hydroxyandrostenedione and 11-ketotestosterone did not stimulate GVBD. 17α, 20βdihydroxy-4-pregnen-3-one (17α, 20βdiOHprog) and deoxycorticosterone (DOC) were the most potent steroids in stimulating final oocyte maturation. The results indicate that C21 hydroxylated steroids are potent inducers of final maturation in mullet. Further, co-incubations with 17β-estradiol, cortisol and testosterone did not alter the maturation-inducing effects of HCG or 17α,20βdiOHprog. Cyanoketone, a blocker of 3βHSD activity, was only partially effective in blocking GVBD induced by HCG. This suggests that Δ5 (pregnenolone derived) and Δ4 steroids may be involved in final oocyte maturation in this species.
5 citations
01 Jan 1987
4 citations
TL;DR: In this paper, the authors deal with the problem of strong practical stability for discontinuous, nonautonomous, nonlinear large scale systems and obtain sufficient conditions for various strong practical instability or instability.
3 citations
TL;DR: In this paper, the defects and their thermal treating behavior in LEO GaP:S were investigated by PAT and the positron lifetime was measured at room temperature on samples after isochronal annealing from 200 to 600°C.
Abstract: The defects and their thermal treating behaviour in LEC GaP:S are investigated by PAT. The positron lifetime is measured at room temperature on samples after isochronal annealing from 200 to 600°C. Two components τ1 and τ2 of the positron lifetime in GaP: S are obtained. τ1 is the positron lifetime of the free state in the perfect zone of the crystal. τ2 is the positron lifetime of the trapped state in the defect zone of the crystal. Results show that the positron average lifetime τ is 228 ps and τ1 = 209 ps, τ2 = 388 ps in the non-thermal treated sample. During the thermal treating process, τ1 is unchanged but τ2 is changed in two stages. The results are analyzed by a defect reaction model.
Defekte und ihr thermisches Verhalten werden in LEO GaP:S mit PAT untersucht. Die Posi-tronenlebensdauer wird bei Raumtemperatur an Proben gemessen, welche isochron zwischen 200 und 600 °C getempert werden. In GaP: S werden zwei Komponenten τ1 und τ2 der Positronenlebens-dauer erhalten. τ1 ist die Lebensdauer der freien Positronen im perfekten Bereich des Kristalles, wahrend τ2 die Lebensdauer der an Defekten eingefangenen Positronen ist. Die Ergebnisse zeigen, das in nicht thermisch behandelten Proben die mittlere Lebensdauer τ2 = 228 ps und τ1 = 209 ps sowie τ2 = 388 ps betragt. Wahrend der thermischen Behandlung bleibt τ1 ungeandert, jedoch τ2 andert sich in zwei Stufen. Die Ergebnisse werden mit einem Defektreaktionsmodell analysiert.
1 citations
TL;DR: In this article, the nucleon is considered as a thermodynamical system composed of partons; its quarks and gluons obey Fermi and Bose statistics, respectively.
1 citations
TL;DR: In this paper, the notions of Schauder bases and decompositions for a Sobolev space are used as an approximation method for solving the identification problem of time-varying systems.
Abstract: In this paper, the notions of Schauder bases and decompositions for a Sobolev space are used as an approximation method for solving the identification problem of time-varying systems. This extends the results obtained by Chen (1983). A numerical approximation is discussed.
1 citations
TL;DR: Application of a glassy-carbon tubular electrode to determination of traces of bismuth in environmental water samples by differential-pulse anodic-stripping voltammetry is described.
TL;DR: Based on the equilibrium structure, a decomposition analysis method of large scale dynamic systems is presented in this paper, which is useful in dealing with nonlinear systems, especially when the subsystems of them are strongly coupled.
TL;DR: In this article, the effect of Cr, Cu, Hg, and Zn on diatom growth was investigated and it was shown that a higher nutrient level can have a negative impact on the diatom production.
Abstract: This paper is based on the results of simulation experiments and annual observations on the effect of Cr, Cu, Hg, and Zn on diatom (Chaetoceros sp.Skeletonema costatum andMelosira sulcata) growth. Laboratory experiments reveal many physico-chemical parameters play an important role in the toxicity and accumulation of metals in organisms. The mesotrophic level in the water environment is related to phytoplankton growth. A higher nutrient level can have a negative impact on diatom production. Several of the above metals coexist in the investigated region and exert mainly a negative effect on growth.