Additional file 2: of Recalcitrant carbon controls the magnitude of soil organic matter mineralization in temperate forests of northern China

Raw data for mineralized SOC during a given incubation period under different conditions for three forest types. (DOCX 27 kb

Additional file 1: of Recalcitrant carbon controls the magnitude of soil organic matter mineralization in temperate forests of northern China

Labile carbon pool and decomposition constants estimated by a two-compartment modelunder different incbuation conditions for three forest types. (DOC 54 kb

Electronic Structure and Luminescence of 1.1- and 1.4-nm Silicon Nanocrystals: Oxide Shell versus Hydrogen Passivation

The difference between oxide and hydrogen passivation of small Si nanocrystals is explored by all-electron, hybrid functional DFT calculations with unrestricted geometry optimization. Oxide passivation lowers the band gap by about 2.4 eV for Si35 cores and by about 1.5 eV for Si66 cores. The oxide-passivated nanocrystals have optically forbidden, indirect-gap-type transitions whereas the hydrogen-passivated nanocrystals have optically allowed, direct-gap-type transitions. The HOMO and LUMO are delocalized in both species. This result explains the experimental observation that hydrogen-passivated Si nanocrystals luminesce in the blue whereas oxide-passivated Si nanocrystals luminesce in the yellow-red

Variation in basal parameters of soil respiration within or between forest types.

<p>The significance of differences of basal parameters between forest types were separately tested by independent t - test (two - tailed) at α = 0.05 (n = 9 in the broadleaved forest, and 11 in the mixed forest). Same lowercase letter means no significant difference is detected at α = 0.05 within 95% confidence interval between the two forest types.</p

Trends of R₁₀ and Q₁₀ with basal area ratio of coniferous to broadleaved tree species.

<p>Trends of R₁₀ and Q₁₀ with basal area ratio of coniferous to broadleaved tree species.</p

Relationships between soil chemical properties and Q₁₀ respectively in broadleaved and mixed forest types.

<p>Relationships between soil chemical properties and Q₁₀ respectively in broadleaved and mixed forest types.</p

Reactive Extraction of Saturated Aliphatic Dicarboxylic Acids with Trioctylamine in 1‑Octanol: Equilibria, Model, and Correlation of Apparent Reactive Equilibrium Constants

Extraction equilibria for saturated aliphatic dicarboxylic acids, namely oxalic, malonic, succinic, and adipic acids, with trioctylamine (TOA) in 1-octanol were determined at various TOA concentrations. Using quantitative FT-IR spectra, we determined that the formation of 1:2 acid–amine complexes depends on the p<i>K</i>_a2 value, and wavenumbers of specific peaks for the COO^– of the acid–amine ion-pair complexes depend on the p<i>K</i>_a1 value. An equilibrium model is presented that employs the mass action law and is used to determine model parameters and apparent extraction equilibrium constants (<i>K</i>₁₁, <i>K</i>₁₂, and <i>K</i>₂₁). The extraction abilities for dicarboxylic acids depend on the p<i>K</i>_a1 value. The typical overloading curves of TOA/1-octanol for dicarboxylic acids are given. The loadings of TOA calculated using the equilibrium model parameters and apparent extraction equilibrium constants agree with the experimental data. The apparent extraction equilibrium constants depend on the acidity of the dicarboxylic acid and the specific basicity of TOA. The quantitative correlation of log <i>K</i>₁₁ (or log <i>K</i>₁₂) is obtained using p<i>K</i>_a1 (or p<i>K</i>_a2) and p<i>K</i>_a,B^′

Electronic Structure of 1 to 2 nm Diameter Silicon Core/Shell Nanocrystals: Surface Chemistry, Optical Spectra, Charge Transfer, and Doping

Static and time-dependent density functional calculations, geometrically optimized and including all electrons, are described for silicon nanocrystals as large as Si87H76, which contains 163 atoms. We explore and predict the effect that different sp3 passivation schemesF or H termination, thin oxide shell, or alkane terminationhave on the HOMO and LUMO, on the optical spectra, and on electron transfer properties. Electronegativity comparisons are a useful guide in understanding the observed deviation from the simple quantum size effect model. Nanocrystals containing Al or P impurity atoms, either on the surface or in the interior, are explored to understand electrical doping in strongly quantum-confined nanocrystals. Surface dangling bonds are found to participate in internal charge transfer with P atom dopant electrons

Correlations of R₁₀ with basal area and CV of shrub carbon stock separately for both forest types.

<p>Correlations of R₁₀ with basal area and CV of shrub carbon stock separately for both forest types.</p

The effects of biophysical variables on R₁₀ and Q₁₀ analyzed by the method of Redundancy Analysis (RDA).

<p>SBD: soil bulk density; DBH: diameter at breast height.</p>a<p>Describe marginal effects, which shows the variance when the variable is used as the only factor.</p>b<p>Describe conditional effects, which shows the additional variance each variable explains when it is included in the model.</p>c<p>The level of significance corresponding to Lambda-A when performing Monte Carlo test (with 499 random permutations) at the 0.05 significance level.</p>d<p>The Monte Carlo test statistics corresponding to Lambda-A at the 0.05 significance level.</p