[1] Agreement among instruments is very important for the Multi-Scale Observation Experiment on Evapotranspiration over heterogeneous land surfaces of The Heihe Watershed Allied Telemetry Experimental Research (HiWATER-MUSOEXE), particularly in regard to radiation and turbulent flux measurements. Before HiWATER-MUSOEXE was conducted, 20 eddy covariance (EC) system sets, 18 radiometer sets, and seven large aperture scintillometers (LASs) sets were intercompared over the Gobi desert between 14 and 24 May 2012. For radiometers, the four-component radiation measurements exhibited good agreement -the average root-mean-square error (RMSE) and mean relative error (MRE) for the net radiation were 10.38 W m À2 and 1.24%, respectively. With regard to the EC systems, the best consistency for sensible heat fluxes was found among CSAT3 sonic anemometers and Li7500A/Li7500/EC150 combinations (average RMSE, 12.30 W m À2 and MRE, À1.36%), followed by Gill sonic anemometers and Li7500A/Li7500 combinations when a proper angle of attack correction method was applied (average RMSE, 16.75 W m À2 and MRE, À5.52%). The sensible heat flux measured using different LASs agreed well with high correlation coefficients -the average RMSE and MRE values were 10.26 W m À2 and 5.48% for boundary layer scintillometer (BLS) 900, 16.32 W m À2 and 10.47% for BLS450, and 14.38 W m À2 and À3.72% for ZZLAS, respectively. The EC and LAS measurements were compared and agreed well over homogeneous underlying surfaces, which also indicated that the EC and LAS measurements would be comparable in the follow-up experiment. The intercomparison results can be used to determine instrument placement and are very helpful for subsequent data analysis.
Surface soil heat flux is a component of surface energy budget and its estimation is needed inland-atmosphere interaction studies. This paper develops a new simple method to estimate soil heat flux from soil temperature and moisture observations. It gives soil temperature profile with the thermal diffusion equation and, then, adjusts the temperature profile with differences between observed and computed soil temperatures. The soil flux is obtained through integrating the soil temperature profile. Compared with previous methods, the new method does not require accurate thermal conductivity. Case studies based on observations, synthetic data, and sensitivity analyses show that the new method is preferable and the results obtained with it are not sensitive to the availability of temperature data in the topsoil. In addition, we pointed out that the soil heat flux measured with a heat-plate can be quite erroneous in magnitude though its phase is accurate. soil heat flux, thermal conductivity, temperature correction, heat-plate
[1] Land-atmosphere interactions on the Tibetan Plateau are important because of their influence on energy and water cycles on both regional and global scales. Flux variance and eddy covariance methods were used to measure turbulent fluxes of heat, water vapor, and momentum over a Tibetan shortgrass prairie during the Global Energy and Water Cycle Experiment (GEWEX) Asian Monsoon Experiment (GAME) in 1998. Under unstable conditions during the monsoon period (July-September), the observed standard deviations of temperature and specific humidity (normalized by appropriate scaling parameters) followed the Monin-Obukhov theory. The similarity constants for heat C T and water vapor C q in their dimensionless functions of stability under a free convection limit were both 1.1, unlike the differences (i.e., C T C q ) reported in other studies. While the transfer efficiency of heat and water vapor exchange generally agreed with the prediction from the Monin-Obukhov theory, momentum exchange was less efficient than predicted. In comparison with the eddy covariance data, the flux variance method (with C T = C q = 1.1) underestimated both heat and water vapor fluxes by <5%. When the eddy covariance data were absent, the flux variance method was used for gap filling the seasonal flux database. To estimate latent heat flux during the premonsoon period in June, C T /C q was approximated as r Tq (where r Tq is a correlation coefficient for the fluctuations of temperature and water vapor) because of the sensitivity of C q to changes in soil moisture conditions. The dramatic changes in the Bowen ratio from 9.0 to 0.4 indicate the shift of energy sources for atmospheric heating over the plateau, which, in turn, resulted in the shift of turbulent exchange mechanisms for heat and water vapor.
In the past 40 years, the nanoparticle drug delivery system for tumor peptide vaccines has been widely studied which also reached a splendid result. Nanomaterial can enhance the targeting of vaccines, help vaccines enter the cells and trigger immune response by themselves. They also help in increasing cellular uptake, improving permeability and efficacy. Currently, several categories of nanopreparation, such as liposome, polymeric micelle, polymeric nanoparticle, gold nanoparticle and so on, are proved that they are appropriate for peptide vaccines. This review we discussed the possible mechanisms of nanomaterial’s action on the regulation of immunological functions and several major applications of this advanced drug delivery system for tumor peptide vaccine.
A unique and intensive flux observation matrix was established during May to September of 2012 in an oasis–desert area located in the middle reaches of the Heihe River basin, China. The flux observation matrix included 22 eddy covariance systems belonging to the first thematic experiment of the Heihe Watershed Allied Telemetry Experimental Research (HiWATER) project. The energy balance closure ratio (EBR) was assessed and possible mechanisms were investigated using remote sensing data. The results showed that 1) the EBR was in the range of 0.78–1.04 at all sites with an average EBR of 0.92, and 2) the calculated daily EBR exhibited better performance than the 30-min averages. 3) The heat storage cannot be ignored during the crop growing season. An improvement of approximately 6% in the total closure was found after considering the heat storage terms (canopy and photosynthesis storage) in the energy budget at the maize surface, and the canopy and photosynthesis showed approximately equal contributions of 3% for each storage term. The results also showed that 4) the land heterogeneous surface had a significant effect on the EBR. The EBR decreased with land surface heterogeneity increasing (taking the standard deviation of the surface temperature in the eddy covariance system source area as an index). The EBR also decreased when irrigation occurred and increased after irrigation was completed. The advection or secondary circulation broke the closed system of the energy balance given the phenomenon of EBR increasing when the advection or secondary circulation occurred.
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