[Effects of Eucalyptus grandis leaf litter decomposition on the growth and photosynthetic characteristics of Cichorium intybus].

A pot experiment was conducted to study the effects of Eucalyptus grandis leaf litter during its early stage decomposition on the growth and the photosynthesis of Cichorium intybus. Each pot contained 12 kg soil mixed with different amounts of E. grandis leaf litter (30 g x pot(-1), A1; 60 g x pot(-1), A2; 90 g x pot(-1), A3; and 0 g x pot(-1), CK), and sowed with C. intybus. The growth indicators and the photosynthetic characteristics of C. intybus were measured after the third leaf of C. intybus seedlings fully expanded in treatment A3. At the early stage of leaf litter decomposition, the C. intybus biomass accumulation, leaf area growth, and synthesis of photosynthetic pigments were inhibited significantly, and the inhibition effect was getting stronger with the increasing amount of the leaf litter addition. The intercellular CO2 concentration of C. intybus was increased by litter addition, while the net photosynthetic rate, stomatal conductance, and transpiration rate were significantly lower than those of the control. With the increase of leaf litter addition, all the parameters of C. intybus light response and CO2 response except CO2 compensation point showed an obvious downward trend, and there existed significant differences between the treatments of litter additions and the control. It was suggested that during the decomposition of E. grandis leaf litter, its allelopathic substances released gradually and acted on receptor plants, inhibited the synthesis of photosynthetic pigments and the photosynthesis of the receptors, decreased the receptors environmental adaptation ability, and accordingly, inhibited the growth of C. intybus.

[Spectroscopic analysis of Nd:GGG laser crystal].

Neodymium-doped gadolinium gallium garnet (Nd:GGG)crystal is the best operation material of solid-state heat-capacity laser. In the present paper, Nd:GGG single crystal was grown by Czochralski (Cz) method. Fluorescence spectra and absorption spectra were measured. At the same time, the spectral parameters of Nd:GGG laser crystal were calculated by Judd-Ofelt theory, including absorption and emission cross-section, intensity parameters, radiative transition probability, fluorescence branch ratio and fluorescent lifetime. According to the measurement and calculation of absorption spectra, it is illustrated that the main absorption peak of Nd: GGG crystal was at near 808 nm, the absorption cross section of the main peak at 808 nm sigma abs, was equal to 4. 35 x 10(-20) cm2. The FWHM of absorption line-width was equal to 8 nm, and the absorption intensity became stronger with the increase in Nd3+ ions concentration. According to the measurement and calculation of fluorescence spectra, the fluorescence emission peak was at near 1062 nm, which corresponds to 4F(3/2) - 4(I(11/2) emission band of Nd3+ ions. The radiative transition probabilityof the main emission peak at 1062 nm A(jj') was equal to 1 832.01 s(-1). The fluorescence branch ratio betajj was equal to 45.07%. The fluorescence lifetime r was equal to 250 micros. The stimulated emission cross section sigma(lamda) was equal to 21.58 x 10(-20) cm2. The laser operationof 4F(3/2) - 4I(11/2) transition can be realized due to the larger fluorescence branch ratio and stimulated emission cross section

[Study on crystal growth and vibrational spectra of Yb(x) : KY(1-x) (WO4)2].

Yb(x) : KY(1-x)W (x = 0.05)and KYbW crystals were grown by TSSG method. Both of the structure and spectral properties were compared. The condition for the crystal growth is: the rotation rate 10-15 r x min(-1), the pulling speed 1-2 d(-1), the growing period 10-15 d, cooling growing speed 0.05-0.1 degrees C x h(-1), and the cooling speed 20 degrees C x h(-1). X-ray powder diffraction analysis was performed for the crystal powder. They belong to beta-KYW structure with low thermal phase. The cell parameters of the two crystals were calculated, and they are respectively a1 = 1.063 nm, b1 = 1.034 nm, c1 = 0.755 nm, beta1 = 130.75 degrees, Z1 = 4 and a2 = 1.061 nm, b2 = 1.029 nm, c2 = 0.749 nm, beta2 = 130.65 degrees and Z2 = 4. The infrared spectrum and Raman spectrum of crystal were measured. The sample of Yb(x) : KY(1-x) W (x = 0.05) had stronger infrared absorption peaks at 925, 891, 840, 777 and 749 cm(-1), which were caused by stretching vibration. The sample of KYW had stronger infrared absorption peaks at 484 and 437 cm(-1) caused by bending vibration. The vibration modes were analysed and vibrational frequencies of vibratory activity was assigned. The two crystals had strong Raman activity. The vibration of WOOW and WOW exists from 200 to 1000 cm(-1).

[Changes in serum contents of inflammatory mediators after tetramethylene-disulfo-tetramine poisoning and clinical study of a new treatment regime for the poisoning].

OBJECTIVE: To study the changes in serum contents of beta-endorphin (beta-EP), endothelins (ET), nitric oxide (NO) and tumor necrosis factor (TNF) after acute tetramethylene-disulfo-tetramine (TDT) poisoning and therapeutic effect of a new treatment regime. METHODS: (1) Forty-eight patients with tetramethylene-disulfo-tetramine poisoning (experiment group) were enrolled in this study. The serum levels of beta-EP, ET, NO and TNF were measured upon hospitalization and 1, 3, 5, 7, 9, 11, 13, 15, 17 and 19 days after poisoning, respectively, and compared with those of 30 healthy individuals (control group B). (2) They were treated with the improved regime and compared with patients treated with the conventional regime designated as control group A. RESULTS: (1) In 48 patients treated with improved regime, 45 were cured and 3 died. (2) The serum levels of beta-EP, ET, NO and TNF from 45 patients who were cured were significantly higher at hospitalization compared with those of healthy individuals, with the peak values appeared on day 1 after poisoning in the mild, moderate and severe groups. Beta-EP levels returned to normal range on days 9, 13 and 17 after poisoning respectively in the mild, moderate and severe groups. ET levels returned to normal range on days 7, 13 and 15 after poisoning respectively in the mild, moderate and severe groups. NO levels returned to normal range on days 7, 11 and 11 after poisoning respectively in the mild, moderate and severe groups. TNF levels returned to normal range on days 9, 11 and 17 after poisoning respectively in the mild, moderate and severe groups. (3) The serum levels of beta-EP, ET, NO and TNF in 3 non-survivors were very high at hospitalization and continued to increase in the course of treatment. (4) The cumulative doses of diazepam and Phenobarbital, and the eclampsia time were significantly less in the experiment group than those of control group A. CONCLUSION: (1) The serum levels of beta-EP, ET, NO and TNF are correlated with the severity of tetramethylene-disulfo-tetramine poisoning and general conditions of the patients. (2) When the serum levels of beta-EP, ET, NO and TNF decrease gradually in the course of treatment, prognosis is better. On the contrary, the prognosis is poor when their levels increase gradually. (3) Measures to decrease levels of beta-EP, ET, NO and TNF result in a better prognosis of patients with tetramethylene-disulfo-tetramine poisoning. (4) The improved regime can be considered a better therapeutic strategy in tetramethylene-disulfo-tetramine poisoning.