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Sarglanoids A–F, six new sesquiterpenoids belonging to eudesmane ( 1 – 5 ) and eremophilane ( 6 ) types, were isolated from the leaves of Sarcandra glabra, a famous traditional Chinese medicine (TCM). Their structures including absolute configurations were elucidated through extensive spectroscopic analyses and electronic circular dichroism (ECD) calculations. Thereinto, compounds 1 – 2 were rare N-containing eudesmane-type sesquiterpenoids. Compound 3 exhibited inhibitory activity against nitric oxide (NO) production in lipopolysaccharides (LPS)-induced RAW 264.7 cells with IC50 values at 20.00 ± 1.30 μM. This research provides scientific basis for sesquiterpenoids as the medicinal material foundation of S. glabra.

Soil incubation experiments were conducted in lab to delineate the effect of soil temperature and soil water content on soil respirations in broad-leaved/Korean pine forest (mountain dark brown forest soil), dark coniferous forest (mountain brown coniferous forest soil) and erman's birch forest (mountain soddy forest soil) in Changbai Mountain in September 2001. The soil water content was adjusted to five different levels (9%, 21%, 30%, and 43%) by adding certain amount of water into the soil cylinders, and the soil sample was incubated at 0, 5, 15, 25 and 35°C for 24 h. The results indicated that in broad-leaved/Korean pine forest the soil respiration rate was positively correlated to soil temperature from 0 to 35°C. Soil respiration rate increased with increase of soil water content within the limits of 21% to 37%, while it decreased with soil water content when water content was over the range. The result suggested the interactive effects of temperature and water content on soil respiration. There were significant differences in soil respiration among the various forest types. The soil respiration rate was highest in broad-leaved/Korean pine forest, middle in erman's birch forest and the lowest in dark coniferous forest. The optimal soil temperature and soil water content for soil respiration was 35°C and 37% in broad-leaved/Korean pine forest, 25°C and 21% in dark coniferous forest, and 35°C and 37% in erman's birch forest. Because the forests of broad-leaved/Korean pine, dark coniferous and erman's birch are distributed at different altitudes, the soil temperature had 4–5°C variation in different forest types during the same period. Thus, the soil respiration rates measured in brown pine mountain soil were lower than those in dark brown forest and those measured in mountain grass forest soil were higher than those in brown pine mountain soil.

The N2O emission rates, photosynthesis, respiration and stomatal conductance of the dominant tree species from broadleaf/Korean pine forest in Changbai Mountain were measured by simulated water stress with the closed bag-gas chromatography. A total of five species seedlings were involved in this study, i.e.,Pinus koraiensis Sieb. et Zucc,Fraxinus mandshurica Rupr,Juglans mandshurica Maxim,Tilia amurensis Rupr, andQuercus mongolica Fisch. ex Turcz.. The results showed that the stomatal conductance, net photosynthetic rate and N2O emission of leaves were significantly reduced under the water stress. The stoma in the leaves of trees is the main pathway of N2O emission. N2O emission in the trees mainly occurred during daytime. N2O emission rates were different in various tree specie seedlings at the same water status. In the same tree species, N2O emission rates decreased as the reduction of soil water contents. At different soil water contents (MW, LW) the N2O emission rates ofPinus koraiensis decreased by 34.43% and 100.6% of those in normal water condition, respectively. In broadleaf arbor decreased by 31.93% and 86.35%, respectively. Under different water stresses N2O emission rates in five tree species such asPinus koraiensis, Fraxinus mandshurica, Juglans mandshurica, Tilia amurensis, andQuercus mongolica were 38.22, 14.44, 33.02, 16.48 and 32.33 ngN2O·g−1DW·h−1, respectively.

Soil water stress was studied on the potted seedlings of five dominant tree species (Pinus koraienes Sieb. et Zucc.,Fraxinus mandshurica Rupr.,Juglans mandshurica Maxim,Tilia amurensis Rupr. andQuercus mongolica Fisch. ex Turcz) from the broadleaved/Korean pine forest in Changbai Mountain. Leaf growth, water transpiration and photosynthesis were compared for each species under three soil moisture conditions: 85%–100% (high water, CK), 65%–85% (Medium water, MW) and 45%–65% (low water, LW) of 37.4% water-holding capacity in field. The results showed that the characteristic of typical drought-resistance of the leaves is significantly developed. The net photosynthetic rate and water use efficiency ofFraxinus mandshurica were higher in MW than those in CK. But for the other four species, the net photosynthetic rate and water use efficiency in CK were lower than those in MW and LW. The transpiration rate responding to soil moistures varied from species to species.

The study on NOx Storage Performance at low temperature over Pt/BaO/Al_2O_3 by plasma treatment in this paper, the structure and activity of catalysts are characterized and tested respectively by using BET, TPR, SEM, TPD,XRD and FTIR. The results of FTIR spectra are shown that catalyst by non-plasma treatment has weak oxidbillity for NO, on the surface of catalyst, there are major adsorption species of bridge nitrite, and a small quantity of monodentate nitrate, bidentate nitrate and NO_2 adsorbing species. There are major monodentate nitrate on the surface of catalysts by plasma treatment, the catalysts by plasma treatment have highly metal dispersibility and biggish specific surface area, which should improveNOx storage capacity at low temperature.