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The thermal properties of raw wood (RW) biomass, corresponding pyrolytic wood (PW) biomass, and their blends with anthracite coal (AC) were evaluated under combustion conditions with a thermogravimetric analysis (TGA) method. The blending ratios of the biomass with AC ranging from 0 to 100 mass% were taken into consideration to investigate the thermal behavior and kinetics of these blends during their co-combustion. For blends with different ratios of the RW to AC and 100% AC (100 AC), two distinct mass loss peaks related to the release or combustion process of the volatiles and the combustion of the char were noted. The addition of a higher ratio of RW or PW into AC can improve the combustion process of the blends. The thermal behavior of the RW/AC or PW/AC blends could not be characterized by a simple linear correlation of their pure material thermal behavior. With the RW/PW addition ratios varying from 25 mass% to 80 mass%, the apparent activation energy of the blends gradually decreased from 48. 46 to 34. 93 kJ/mol and from 82. 74 to 37. 81 kJ/mol for the RW/AC and PW/AC blends, respectively, with high correlation coefficient (R2) values ranging from 0. 995 6 to 0. 9984.

The combustion characteristics and kinetics of anthracite, pine sawdust and their blends were investigated under combustion condition by thermogravimetric analysis, respectively. The fractions of pine sawdust in the blended samples were set to be 30%, 50%, and 80%. The results showed that the ignition and burnout temperatures of pine sawdust were lower and the maximum combustion rate was higher than those of anthracite. With the increase of pine sawdust content, the ignition temperature and burnout temperature of the blends decreased, while the maximum mass loss rate and the combustible index of the blends increased; that is, the comprehensive combustion property became better. The kinetic parameters for the blends combustion under air condition were calculated based on experimental results using Coats-Redfern model. When the pine sawdust content varied in the range of 30%—80%, the combustion processes of these blends could be divided into two stages and the combustion reactions belong to the first-order reaction. The values of apparent activation energy at two individual stages decreased from 68. 78 to 47. 28 kJ • mol–1 and from 113.53 to 46.43 kJ • mol−1, respectively.

A novel chromatic dispersion (CD) monitoring technique based on asynchronous amplitude histogram (AAH) for higher order modulation formats is proposed in this paper. Without demodulating the signal, in the monitoring scheme, the received signal is sampled asynchronously, and thus clock information and high-speed sampling units are unnecessary, resulting in low cost and high reliability. Simulations of CD monitoring technique for non-return-to-zero/return-to-zero (NRZ/RZ) 16- and 64-quadrature amplitude modulation (QAM) systems with different optical signal-to-noise ratios (OSNRs) and duty cycles are investigated, and the tolerance of the scheme is also discussed. Simulation results show that the presented CD monitoring technique with high sensitivity can be applied to monitor the residual CD of a transmission link in the next-generation optical networks.

By combining sand tank tests with numerical simulations, this paper studies the temperature fields around constant heat sources to reveal the mechanism of the natural convection and its influence on the temperature fields in the process of energy storage. Using the “24-channel temperature auto acquisition system” developed by our research group in the tests, the temperatures are recorded at measuring points within the research area in the tests, the revised Brinkman equation and a transfer-convection balance model are used for solving the aquifer water-thermal coupling problems, and through comparison of the test results with the calculation results, it is discovered that the influence ranges and the variations of the two temperature fields are consistent, which validates the mathematical model. On the basis of this, we also study the influences of the heat source positions and the boundary conditions on the temperature fields, and the results show that, under the natural convection, the heat source positions may influence the distribution of the temperature fields, thus affect the energy storage. For the same energy storage layer, the temperature field for the top energy storage is characterized by a smaller heat influence range and a relatively concentrated temperature distribution. However, when the heat source is at the bottom, the range of a temperature field, and the temperature is relatively dispersed, which is not favorable to heat recycle, with the same heat source position, the boundary conditions determine the size of the critical Rayleigh number, and thus have an influence on the occurrence and the strength of the natural convection, and accordingly, on the temperature fields.

We report on a rapid method for the detection of Salmonella O8. It does not require an enrichment step but rather uses an aptamer as a probe that was selected by system evolution of ligands by exponential enrichment (SELEX) assay. Firstly, aptamer against Salmonella O8 was selected from a 78 bp random DNA library that was prepared in-vitro. The binding ability of the aptamers to target bacterium was examined by aptamer-linked immobilized sorbent assay. A high affinity aptamer was successfully selected from the initial random DNA pool, and its secondary structure was also investigated. Next, this high affinity aptamer B10 was used to recognize Salmonella O8 via fluorescence microscopy. The selected aptamer has a high specificity and high affinity against its target. We believe that the resulting fluorescence in-situ labeling assay is a potentially useful alternative in rapid screening and detection of foodborne pathogens.

Polypropylene (PP)/polybutene-1 (PB) alloys within reactor were prepared by MgCl2-supported Ziegler-Natta catalyst with sequential two-stage polymerization technology. First, propylene homo-polymerizations were carried out to form isotactic polypropylene (iPP) particles containing active catalyst. Then, butene-1 was subsequently polymerized to form polybutene-1 phase inside the iPP particles. Finally, iPP/PB alloys with spherical shape and adjustable PB content were synthesized. The catalytic activity and catalytic stereospecificity of the Z-N catalyst in the two-stage polymerization process are discussed. The composition and physical properties of the PP alloys were characterized by FT-IR, 13C-NMR, SEM, DSC and XRD. It was found that the in-reactor PP alloys are mainly composed of PP and PB with a little amount of poly(buteneco-propylene) random copolymers and poly(butene-block-propylene) block copolymers. SEM measurements verified that the PB phases with size in the range of 300–400 nm dispersed in the PP matrix uniformly. The incorporation of PB upon the PP matrix affects the properties of final products greatly.

The dynamics of genuine three-qubit entanglement in Ising spin model is investigated under the effect of impurities with different sites. The analytic expression for the three-tangle measurement is obtained. Results show that the impurity parameters exert great effect on the entanglement value. When the impurity on the boundary sit of the spin chain, the positive contribution of the impurity coefficient on the exchange interaction is greater, the stay time in the greater entanglement is longer. When the impurity sitting in the spin chain, the entanglement variation is periodic with the evolution time only at some given impurity coefficient. The realization of efficient control of the entanglement by appropriate combinations of the tunable parameters should be possible.

CJZ3, a lomerizine derivative, modulates P-glycoprotein function in rat brain microvessel endothelial cells

Modulation of P-glycoprotein function by amlodipine derivatives in brain microvessel endothelial cells of rats