Results 1 - 10 of 71
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[en] The subjects discussed in this presentation are estimates of the market for Clean Development Mechanisms (CDM) in China, current CDM activities in China, barriers and counter measures regarding to CDM project development in China, and sectoral priority and market potential of CDM projects in China
[en] This experiment was performed to investigate the effects of acclimated sewage sludge (ASS) and sterilized ASS on the fates of chlorpyrifos (CP) in soil with or without cadmium (Cd), as well as the improvement of soil biochemical properties. Results showed that both ASS and sterilized ASS could significantly promote CP dissipation, and the groups with ASS had the highest efficiency on CP removal, whose degradation rates reached 71.3%–85.9% at the 30th day (40.4%–50.2% higher than non-sludge groups). Besides, the degradation rate of CP was not severely influenced by the existence of Cd, and the population of soil microorganism dramatically increased after adding sludge. The soil enzyme activities (dehydrogenase, acid phosphatase and FDA hydrolase activities) ranked from high to low were as follows: groups with sterilized ASS > groups with ASS > groups without sludge. Simultaneously, 16S rRNA gene sequencing revealed that ASS changed bacterial community structure and diversity in soil. In addition, alkali-hydrolyzable nitrogen and Olsen- phosphorus increased after application of sludge, indicating that the addition of ASS (or sterilized ASS) could effectively improve soil fertility. - Highlights: • Acclimated sewage sludge efficiently enhanced the dissipation of chlorpyrifos in soil. • The degradation efficiency of chlorpyrifos was not significantly affected by Cd. • The application of ASS greatly influenced the bacterial community structure in soil. • The presence of acclimated sewage sludge enhanced the soil biochemical quality. • The soil fertility improved after remediation.
[en] There are some disadvantages in current input-output models for energy. This study proposes a methodology named hybrid physical input-output model for energy analysis (HPIOMEA) to study energy metabolism, taking Suzhou in China as an example. The HPIOMEA calculates energy resources in both energetic and mass units and air pollutants in mass units simultaneously from the perspective of energy balance and mass balance, which is beyond the reach of current input-output tables for energy. In addition, it can validate the rationality of the table compilation and energy projection, and illustrate the direct and accumulative effects of energy and air pollutants. The HPIOMEA reflects the physical reality of energy metabolism much better. In addition, future work on energy analysis is proposed. (author)
[en] The dynamical properties of a tumor cell growth system described by the logistic system with coupling between non-Gaussian and Gaussian noise terms are investigated. The effects of the nonextensive index q on the stationary properties and the transient properties are discussed, respectively. The results show that the nonextensive index q can induce the tumor cell numbers to decrease greatly in the case of q > 1. Moreover, the switch from the steady stable state to the extinct state is speeded up as the increases of q, and the tumor cell numbers can be more obviously restrained for a large value of q. The numerical results are found to be in basic agreement with the theoretical predictions
[en] Resistive switching (RS) effect in the double-layered structure of Pt/Pr0.7Ca0.3MnO3 (PCMO)/La0.6Pr0.4MnO3 (LPMO)/SrNb0.01Ti0.99O3 (SNTO) are improved comparing with that in the single-layered structure of Pt/PCMO/SNTO. We propose that the RS characteristics of the two structures depend on the electronic properties of the depletion layer formed in PCMO layer with negative space-charge near the interface of PCMO and LPMO (or SNTO), which should be caused by the migration of oxygen vacancies. Our numerical results show that the negative space-charge region formed in the whole LPMO layer in Pt/PCMO/LPMO/SNTO causes an increase of the electric field, which results in the increase of the number of oxygen vacancies to migrate and thereby improving the RS effect
[en] The 99mTc(CO)3(H2O)-DEDT complex was prepared by a two-step procedure involving the preparation of the precursor fac-[99mTc(CO)3(H2O)3]+, followed by the addition of sodium salt of diethyl dithiocarbamate (DEDT). The radiochemical purity (RCP) of the product was over 90% as measured by thin layer chromatography (TLC). No decomposition of the complex at room temperature was observed over a period of 6 hours. Its partition coefficient indicated that it was a lipophilic complex. The electrophoresis results showed the complex was neutral. Biodistribution in mice demonstrated that the complex can penetrate the intact blood-brain barrier (BBB) and the brain uptake (ID%/g) was 4.22 at 5-minute post-injection, suggesting the complex may lead to a further development of the radiopharmaceutical as a brain perfusion tracer. (author)
[en] Remnant strain has been measured as a function of temperature in (Ba0.8Sr0.2)TiO3 (BST) ceramic by mechanical poling in three point bending configuration. BST ceramic exhibits recoverable macroscopic strain with shape memory effect and three jumps in the temperature-dependent strain during thermal cycling under applied force. The jumps are associated with the three structural phase transitions of BST, as confirmed by the simultaneous measurements of dynamic modulus and internal friction. In addition, the orthorhombic phase of BST exhibits a significantly higher strain comparing to that in the tetragonal and rhombohedral phases. X-ray diffraction confirms that the macroscopic strain is due to ferroelastic domain switching and particularly the dominant contribution to the higher macroscopic strain at orthorhombic phase is the higher probability of non-180 deg. domain switching rather than the variation of domain switching strain at different phases
[en] The ferroelastic phase transition and shape memory effect in La-modified lead zirconate titanate ferroelectric ceramics are demonstrated directly through the temperature-dependent macroscopic recoverable strain measured in a three-point bending configuration. X-ray diffraction measurements reveal that non- 180 deg. domain switching occurs in the mechanically poled sample in two different ways at the bottom and top of the sample which have been under tensile and compressive stresses, respectively. The calculated fraction of non- 180 deg. switched domains in the poled sample increases nonlinearly with the applied force and shows a saturation trend, which is consistent with the nonlinear behavior of the remnant strain. This study confirms that the mechanical stress applied upon cooling ferroelectric ceramics from the paraelectric to the ferroelectric phase can easily activate ferroelastic domain switching and give rise to preferred domain orientation and consequent macroscopic remnant strain which results in a history effect and shape memory effect via the ferroelastic phase transition.
[en] The Pb(Zr,Ti)O3 (PZT) ceramics with Zr/Ti ratios of 30/70, 52/48 and 70/30 and the PZT(52/48) ceramics doped with La, Ta and Co at various percent were prepared by a standard solid-state reaction method, respectively. Internal friction and modulus were measured as a function of temperature at low frequencies by using a inverted torsion pendulum. Two internal friction peaks (P1 and P2), related to oxygen vacancies and domain walls, respectively, were observed in all the undoped PZT ceramics with different Zr/Ti ratios. In addition, a minimum in modulus associated with a phase transition internal friction peak appearing at Curie temperature was observed in all samples. The effects of the Zr/Ti ratios and some dopants (such as La, Ta and Co) on the internal frictions were investigated. The internal friction results indicate the changes of the concentration of oxygen vacancies and the domain structure with the variations of Zr/Ti ratios and dopants, which will be helpful in the utilities of the PZT ceramics. (author)
[en] Strontium bismuth niobate (SBN) matrix composites containing Ag particles were prepared by the conventional solid-state reaction method. With the addition of Ag particles to the SBN matrix, the single-phase layered perovskite structure of the matrix was preserved and the sintering temperature of the system was lowered about 200 deg. C compared with monolithic SBN. The SBN/Ag composites showed a significant increase of the dielectric constant and the loss tangent of SBN/Ag composites decreased in certain Ag content. With increasing Ag content, a gradual increase of the dielectric constant was observed in the temperature range from room temperature to 600 deg. C. The Curie temperature was found to decrease from 439 deg. C for the monolithic SBN to 435 deg. C for the composite with 3.5 vol % Ag, and then with increasing Ag content, the Curie temperature gradually increased to 445 deg. C for the composite with 14 vol % Ag. The results show that the SBN/Ag composites have enhanced dielectric properties and an improved processing condition, which could be further exploited in capacitor applications