Landuse/landcover change (LULCC) and climate change (CC) impacts on streamflow in high elevated catchments are very important for sustainable management of water resources and ecological developments. In this research, a statistical technique was used in combination with the Soil and Water Assessment Tool (SWAT) to the Upstream Area of the Yangtze River (UAYR). Different performance criteria (e.g., R2, NSE, and PBIAS) were used to evaluate the acceptability of the model simulation results. The model provided satisfactory results for monthly simulations in the calibration (R2; 0.80, NSE; 0.78 and PBIAS; 22.3%) and the validation period (R2; 0.89, NSE; 0.75 and PBIAS; 19.1%). Major landuse/landcover transformations from 1990 to 2005 have occurred from low grassland to medium grassland (2%) and wetlands (0.9%), bare land to medium grassland (0.2%), glaciers to wetland (16.8%), and high grassland to medium grassland (5.8%). The results show that there is an increase in average annual runoff at the Zhimenda station in UAYR by 15 mm of, which approximately 98% is caused by climate change and only 2% by landuse/landcover change. The changes evapotranspiration are larger due to climate change as compared to landuse/landcover change, particularly from August to October. Precipitation and temperature have increased during these months. On the contrary, there has been a decrease in evapotranspiration and runoff from October to March which depicts the intra-annual variations in the vegetation in the study area.
Wireless Personal Communications - A triple-band ± 45° dual-polarized dipole antenna is presented in this paper. The proposed antenna covers two n77 bands and one n79 band in... 相似文献
A force sensor design utilizing a photo-interrupter is presented for measuring the static coefficient of friction (COF). The measurement of ice friction on 相似文献
Nickel-doped nanocrystalline ZnO with three different Ni concentrations was incorporated in polyvinylidene fluoride thin film for obtaining free-standing flexible film by sol-gel technique. The effect of Ni–ZnO loading on the optical and microstructural properties of the Ni–ZnO/polyvinylidene fluoride composite films was studied. X-ray photoelectron spectroscopy and Raman studies were performed to characterize the bonding environment. Fluorine-terminated surface showed a strong F1?s peak located at ~695?eV arising out of C–F bonds. Existence of β phase of polyvinylidene fluoride along with the presence of ZnO nanocrystals were indicated by Raman studies. Secondary ion mass spectrometry studies indicated the distribution of Ni–ZnO particles in the polyvinylidene fluoride matrix. 相似文献
A novel polymerizable surfactant (surfmer) based on nonyl phenol ethoxylate backbone and maleic anhydride was synthesized. The chemical structure of the surfmer was characterized by 13C, 1H nuclear magnetic resonance, and surface tension analyses. The surfmer was used in emulsion system of methyl methacrylate/butyl acrylate copolymer at different concentrations to explore its stabilization efficiency using seed emulsion polymerization technique. The result of thermogravimetric analysis showed that the incorporation of the surfmer retarded the decomposing of the polymer chain. The stability of the emulsion was enhanced by adding the surfmer, but the glass transition of the film was decreased dramatically. 相似文献
Samarium doped zinc-magnesium-phosphate glasses having composition (60 – x)P2O5–10MgO–30ZnO–xSm2O3 where x = 0.1, 0.3, 0.6, 1.0 mol % were prepared by melt quenching technique. Archimedes method was used to measure their densitieswhich are lying in the range 2.65–2.91 g/cm3. On the basis of the increasing trend in the density while increasing the content of Sm2O3 it can be concluded that the bridging oxygen is converted to non-bridging oxygen The UV-Vis absorption spectroscopy was carried on in the wavelength range 310–900 nm where the absorption spectra consist of six absorption peaks corresponding to the transitions from the ground state 6H5/2 to various excited energy levels. The optical band gaps are calculated to be 3.93–4.41 eV, 3.31–3.73 eV and 0.27–0.29 eV for direct band gap, indirect band gap and Urbach energy, respectively. The physical parameters like oxygen packing density, refractive index, molar refractivity, metallization, and electronic polarizability are also studied. The Differential Scanning Calorimetry (DSC) technique is used to evaluate the thermal stability. 相似文献
Three new bleach activators for cotton containing pyridinium (PBBC), nicotinamido (NABBC), and 3‐methylpyridinium (3‐PBBC) cationic groups were synthesized and characterized by 1H NMR and HPLC–mass spectrometry. They were then applied to cotton fabric in a bleaching process and evaluated for their performance against the prototype N‐[4‐(triethylammoniomethyl)benzoyl]butyrolactam chloride (TBBC) at a relatively low bleaching temperature (55 °C) and pH 8.5. Measurement of Commission internationale de l’éclairage (International Commission on Illumination) (CIE) whiteness index (WI) values showed that PBBC (WI = 64), NABBC (WI = 58), and 3‐PBBC (WI = 71) impart a significant increase in CIE whiteness compared to a control sample (WI = 40). Among the three new activators, 3‐PBBC exhibited the best performance. Its WI was comparable to that of fabric bleached using the prototype bleach activator TBBC. The acute toxicity of TBBC and the new bleach activators was evaluated using the microcrustacean Daphnia similis. The chronic toxicity of TBBC and 3‐PBBC was evaluated using the green alga Raphidocelis subcapitata, and mutagenicity was evaluated in the Salmonella/microsome assay using the strain TA100. 3‐PBBC was 86 times less toxic to D. similis, 18 times less toxic to R. subcapitata, and 10 times less mutagenic to TA100 in comparison with TBBC. 相似文献
Dielectric function, absorption coefficient, reflectivity, optical conductivity, energy loss spectra, index of refraction and extinction coefficient of AlGaX (X=P, As, Sb) in rocksalt phase, are calculated using full potential linearized augmented plane wave (FP-LAPW) method. All optical parameters are calculated in the incident photon energy range 0–25 eV. The maximum value of optical conductivity observed is 15 000 S. Index of refraction has a maximum value of 4.6. A decrease in the absorption coefficient and optical conductivity is observed when X is replaced by P, As and Sb. The extinction coefficient increases when P is replaced by As and Sb. The high value (n=4.6) of the index of refraction shows that AlGaX is a suitable alloy to be used in making advanced optical devices. 相似文献
Identification of clay minerals present in coal and washery wastes is important in cleaning fine coal by froth flotation and in flocculation and dewatering. Therefore samples of wastes from jigs and the flotation cell at the Zonguldak main coal washery were collected and analyzed petrographically for their mineral matter content and by X-ray diffraction for their clay content. The “loss on ignition” method was carried out to determine their organic carbon and carbonates. The waste samples contain 48–68% clay minerals in addition to silicates, carbonates, sulfides and coal. Three clay minerals were identified, namely illite, kaolinite and chlorite. Illite seemed to be the dominant clay mineral in washery wastes. Loss on ignition indicated high percentages of organic matter in the fine jig tailings (21%) and flotation tailings (33%). 3%–6.5% of carbonates have also been found. 相似文献