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An exceptional phenomenon has been observed that SO2 and NOx in flue gas can be effectively adsorbed over activated carbon with a surprising capacity at cold temperatures with the presence of oxygen. In this study, the adsorption characteristics of NO and SO2 over activated carbon at 80, 20, 0, and − 20 is experimentally investigated. Without the presence of oxygen, adsorption of NO is negligible. In the presence of oxygen, NO can be oxidized to NO2 over activated carbon which leads to the co-adsorption of NO/NO2 within the adsorption bed. Catalytic oxidation of NO over activated carbon can be significantly enhanced at cold temperatures, leading to an extraordinary increase of adsorption capacity of NO. With an initial concentration of NO = 200 ppmv and a space velocity of 5000 h−1, the average specific capacity increases from 3.8 to 169.1 mg/g when the temperature decreases from 80 to – 20 ℃. For NO–O2 co-adsorption, the specific capacity increases along the adsorption bed due to the increasing NO2 concentrations. The adsorption capacity of SO2 is also significantly enhanced at cold temperatures. With an initial concentration of SO2 = 1000 ppmv, the specific capacity increases from 12.9 to 123.1 mg/g when the temperature decreases from 80 to – 20 ℃. A novel low-temperature adsorption (LAS) process is developed to simultaneously remove SO2 and NOx from flue gas with a target of near-zero emission. A pilot-scale testing platform with a flue gas flowrate of 3600 Nm3/h is developed and tested. Emission of both SO2 and NOx is less than 1 ppmv, and the predicted energy penalty is about 3% of the net generation.

Plasma is a partially ionized gas that contains abundant free radicals and UV photons. In this work, the application of low-temperature radio frequency plasma in aflatoxin B1 (AFB1) degradation was investigated and the possible structures of the degradation products were elucidated. It was revealed that AFB1 could be effectively degraded by plasma and exposure to 300 W plasma for 10 min resulted in a degradation rate of up to 88.3 %. Kinetic analysis showed that the degradation process followed a first-order reaction and the generator power was the dominative parameter for AFB1 decomposition. Five major compounds, including 3-(hydromethyl)-8, 9-dihydro-2H-furo[2, 3-h]chromen-8-ol, 1-hydroxy-2-oxo-5-(2, 4, 6-trihydroxy-2, 3, 3a, 8a-tetrahydrofuro[2, 3-b]benzofuran-5-yl)cyclopentanecarboxylic acid, 2-(2, 4-dihydroxy-2, 3, 3a, 8a-tetrahydrofuro[2, 3-b]benzofuran-5-yl)-5-hydroxycyclopent-1-enecarboxylic acid, 1-hydroxy-2-(4-hydroxy-6-methoxy-2-oxo-2, 3, 3a, 8a-tetrahydrofuro[2, 3-b]benzofuran-5-yl)-5-oxocyclopentanecarboxylic acid, and 1, 2-dihydroxy-5-(4-hydroxy-2-oxo-2, 3, 3a, 8a-tetrahydrofuro[2, 3-b]benzofuran-5-yl)cyclopentanecarboxylic acid, were revolved and identified from the degradation product by using UPLC–Q-TOP–MS, and the addition reaction was mainly responsible for AFB1 decomposition. All the five degradation products lost their double bonds in the terminal furan ring and hence theoretically had reduced toxicity compared with AFB1 according to the structure–activity relationship. For this reason, the low-temperature radio frequency plasma is proposed potential in the decontamination of AFB1.

The rheological properties of O-carboxymethyl chitosan (O-CMC) – gum Arabic (GA) coacervates varied greatly with the coacervation pH. At pH 3.0, the coacervate displayed the flow induced shear thickening property in shear rates below 100 s−1 and then behaved as a Newtonian fluid hereafter; at pH 4.5, the coacervate exhibited the characteristic shear thinning property of a pseudoplastic fluid; while at pH 6.0, the coacervate occurred as a Bingham fluid. The highest viscosity and modulus values of the coacervates were recorded not in the pH value with maximum electrostatic interaction. Zeta potential analysis revealed that the high proportion of O-CMC in the coacervates possibly contributed to the unique rheological properties of the coacervates. SEM observation imaged a layer-by-layer structure for the coacervates prepared at pH 3.0, 4.5, and 6.0. It was concluded that the composition of the O-CMC – GA coacervates greatly influenced their rheological properties and the desired property can be obtained by varying the coacervation pH.

The potential of reduced-pressure radio-frequency air plasma (RFAP) in the modification of konjac glucomannan (KGM) was investigated. KGM film was exposed to 100 W RFAP for 50 s, 100 s, 150 s, 200 s, and 250 s, ground, and then subjected to various characterizations. Fourier Transform Infrared Spectroscopy (FTIR) revealed that RFAP treatment increased the content of –OH groups in KGM, with the lowest and highest rise occurring at the exposure durations 150 s and 250 s, respectively. RFAP radiation decreased the solubility of KGM at certain exposure durations, but slightly increased its thermal stability. Exposure to RFAP for 150 s and 250 s increased the hardness of the resultant KGM gel, but decreased the viscosity and elasticity of the KGM solution in a duration-dependent manner. Scanning Electron Microscope (SEM) observation revealed that RFAP treatment led to rougher surfaces and XRD (X-Ray Diffraction) analysis indicated the destroyed crystallinity of KGM. Hence, RFAP has potential application in the modification of KGM.

The possibility of genipin-crosslinked O-carboxymethyl chitosan–gum Arabic coacervate as a pH-sensitive delivery vehicle was investigated. O-carboxymethyl chitosan–gum Arabic coacervates separated in pH 3.0, 4.5, and 6.0 were crosslinked by genipin for different durations and the crosslinked products were subjected to crosslinking degree, swelling behavior, bovine serum albumin release profile, and microstructure characterization. Genipin-crosslinking greatly improved the stability of the coacervates against the simulated gastric solution and created certain pH-sensitivity. The coacervates displayed higher swelling ratios in the simulated gastric solution than in the simulated intestine and colon solutions; meanwhile, the coacervates prepared in pH 4.5 and 6.0 swelled more severely than the complex separated in pH 3.0. Nevertheless, the bovine serum albumin release in the simulated gastric solution from the microcapsules prepared in pH 6.0 was much lower than those prepared in pH 4.5 and 3.0, whose cumulative release percentages in the three simulated solutions were 17.14%, 55.23%, and 79.79%, respectively, in crosslinking duration 2 h. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy analysis revealed that genipin-crosslinking improved the regularity and compactness of coacervate structure, whereas confocal laser scanning microscopy observation indicated that O-carboxymethyl chitosan content was possibly the major reason for the different swelling and bovine serum albumin release behavior of the coacervates. It was concluded that the genipin-crosslinked O-carboxymethyl chitosan–gum Arabic coacervate was a potential intestine-targeted delivery system and its delivery performance could be tailored by varying the crosslinking degree and coacervation acidity.

Based on the principle that one-ended electromagnetic surface wave can drive a plasma antenna, the relation between the effective length of an antenna column and the applied radio frequency (RF) power was studied both theoretically and experimentally. The density distribution along the antenna column as well as the electron temperature in different conditions were investigated. The characteristics of the reception of local frequency modulated (FM) electromagnetic wave by the plasma antenna were compared with that by a copper antenna with same dimensions. The results show that it is feasible to take plasma antennas as receiving ones.

Numerical simulation of the effect of the anode magnetic shielding on the magnetic field and ion beam in a cylindrical Hall thruster is presented. The results show that after the anode is shielded by the magnetic shield, the magnetic field lines near the anode surface are obviously convex curved, the ratio of the magnetic mirror is enhanced, the width of the positive magnetic field gradient becomes larger than that without the anode magnetic shielding, the radial magnetic field component is enhanced, and the discharge plasma turbulence is reduced as a result of keeping the original saddle field profile and the important role the other two saddle field profiles play in restricting electrons. The results of the particle in cell (PIC) numerical simulation show that both the ion number and the energy of the ion beam increase after the anode is shielded by the magnetic shield. In other words, the specific impulse of the cylindrical Hall thruster is enhanced.

Axial propagation characteristics of the axisymmetric surface wave along the plasma in the medium tube were studied. The expressions of electromagnetic field inside and outside the medium tube were deduced. Also, the impacts of several factors, such as plasma density, signal frequency, inner radius of medium tube, collision frequency, etc., on plasma surface wave propagation were numerically simulated. The results show that, the properties of plasma with higher density and lower gas pressure are closer to those of metal conductor. Furthermore, larger radius of medium tube and lower signal frequency are better for surface wave propagation. However, the effect of collision frequency is not obvious. The optimized experimental parameters can be chosen as the plasma density of about 1017 m−3 and the medium radius between 11 mm and 19 mm.

An Hα emission measurement array with 25 detection channels has been built on HL-1M tokamak. Reconstruction maps of Hα emission distribution in plasma cross-section have been obtained by using tomography, with a hydrogen pellet injected into the plasma. The dimension, the shape and the rotation characteristic of the cross-section of the pellet ablation material flow tube have been observed. These results have been analysed and explained tentatively by using the `tail' model and the linear expansion model.

An array of seven HgI2 detectors, which are suitable for detecting the time and space evolution of the x-ray radiation flux and energy spectrum in the range between 15–150 keV relevant to suprathermal electron and runaway electrons was installed on the HL-1M Tokamak (R0=1.02 m, a=0.26 m, BT=3.5 T, IP=350 kA, ne=3–6×1013 cm−3, Te=0.8–1.5 keV). Our iodine mercury (HgI2) semiconductor detectors possess the properties of low noise level, high detection efficiency, high counting rate, high energy resolution, and working at room temperature. Every detector is a high quality, high purity detector cut out of a big size HgI2 crystal. A new type of multichannel energy spectrometer with a high speed acquisition system was developed. Therefore, the spatial and temporal distribution of the x-ray energy spectrum induced by thermal and superthermal electrons can be observed.

The effects of exposure to atmospheric pressure argon plasma on the quality of edible oil were studied. Peanut oil was exposed to the plasma that was generated in voltages ranging from 150–170 V and the variations of peroxide value, iodine value, acid value, and brightness of the resultant products were monitored. Besides, the storage stability of the radiated peanut oil was investigated as well. Plasma treatment did not change the acid value, but reduced the iodine value and increased the peroxide value and brightness of peanut oil in a voltage-dependent manner. Compared with control, exposure to the plasma generated in 170 V significantly decreased the contents of oleic acid and linoleic acid by 2.14 and 2.99% respectively, but exhibited no effect on that of palmitic acid. Storage results revealed that the acid value of the treated peanut oils kept increasing in the 30-day storage period, but the peroxide and iodine values peaked on the 14th and 4th day respectively and then declined gradually. Besides, the voltage-dependent variation pattern was observed for all the three parameters monitored. Since the peroxide, iodine, and acid values of the treated peanut oil are still in the ranges allowed by the Codex Alimentarius standards, it is concluded that the atmospheric pressure argon plasma treatment does not deteriorate the quality of peanut oil and this technology has potential application in the edible oil industry. A total of 5 mL peanut oil is transferred to a weighing bottle (diameter 40 mm) and exposed to atmospheric pressure argon plasma at a flow rate of 0.5 L/h for 100 s. The voltage of the power supply is set to 150, 155, 160, 165, or 170 V to explore the effects of plasma density on peanut oil quality. Treatment by the plasma generated in voltages 0∼170 V shows no effect on the acid value, but significantly reduces the iodine value, increases the peroxide value, and brightness of peanut oil in a voltage-dependent manner. Exposure to the plasma generated in 170 V significantly reduces the contents of oleic acid and linoleic acid by 2.14 and 2.99%, respectively, but exhibits no effect on that of palmitic acid. Practical applications: Peanut oil is rich in oleic acid, linoleic acid and other polyunsaturated fatty acids, as well as vitamin E and other nutrients, it also has high nutritional value and pleasant, peculiar flavor. However, aflatoxin B1 (AFB1) which comes from contaminated peanuts is often detected in peanut oil. An alternative that has been presented for the prevention and control of AFs in food is plasma. The plasma is a quasineutral gas of charged and neutral particles which exhibits collective behavior. The domestic and international research indicates that low temperature plasma has a good restraint of tumor cells, the promotion of gene transfection, coagulation and many other aspects. To our knowledge, the report about atmospheric pressure plasma treatment of aflatoxin has not been found in literature. Atmospheric pressure plasma for degradating AFs has the advantages of good safety, high efficiency, environmental friendliness, and is the developing direction of AFs control. In recent years, the development of atmospheric pressure plasma technology have outpaced the traditional low pressure plasma technology because it does not require the use of vacuum equipment, and it shows its advantage of handling large areas of objects more suited to the practical production line. Accordingly, in this paper, acid value, iodine value, peroxide value, chromatic value, fatty acid content and composition, and storage stability are chosen as detection indexes, to study the effects of atmospheric pressure plasma with different voltage on peanut oil quality, in order to provide theoretical basis for the application of atmospheric pressure plasma technology in vegetable oil industry.

In this paper we investigate the mechanism of singularity formation to the Cauchy problem of quasilinear hyperbolic system.Moreover, we present some examples to show some significant problems.

The prototype neutron flux monitor consists of a high purity 235U fission chamber detector and a "blank" detector, which is a fissile material free detector with the same dimension as the fission chamber detector to identify noise issues such as noise coming from gamma rays. The main parameters of the fission chamber assembly that have been measured in the laboratory are confirmed to approach the technological level of the International Thermonuclear Experimental Reactor (ITER) in the near future. This prototype neutron flux monitor will be further developed to become a neutron flux monitor suitable for the operation phase of D-D fusion on the ITER.

The problem of simultaneous linear estimation of fixed and random effects in the linear mixed model is considered. Necessary and sufficient conditions for a linear estimator of a linear function of fixed and random effects in balanced nested classification models to be admissible are given by Synowka(2008), and his admissible linear estimator is an integral expression. Wang(2009[10]) give another integral expression of this admissible linear estimator, and guesses that apart from these two integral expressions no longer have other integral expressions. Wang(2009[11]) get integral expressions of admissible linear estimators in balanced inverse nested classification models. A class of integral expressions of admissible linear estimators is given in the paper, besides Synowka’s(2008) and Wang’s(2009) results are special cases of these results.

Wavelet analysis is a multiresolution analysis, whose elements have good localization properties in both the spatial and Fourier domains. For different frequencies it has a changeable time-frequency window, so the detector based on wavelet transform is robust. In this paper the detection of signals in noise is discussed and a concept of multiresolution likelihood ratio is put out.

The hydrogenous diamond-like carbon (DLC) films deposited on Si substrates using pulsed glow discharge method are investigated using Raman spectroscopy and X-ray photoelectron spectroscopy method. The UV Raman spectrum for excitation wavelength is 325 nm. UV Raman is particularly useful for hydrogenous DLC, as it gives clear measurements in the D and G peak spectral region even for highly hydrogenated samples, for which the visible Raman spectra are overshadowed by photoluminescence. The sp3 bonding of hydrogenous DLC film can be effectively studied by X-ray photoelectron spectroscopy method, and the data from the X-ray photoelectron spectroscopy method are compared with Raman results. It is found that G peak shows a shift to ward a higher wave under UV excitation. For the G peak, I(D)/I(G), G-FWHM and sp3, there exists a relationship among them.

Five BF33 long counters are arranged in all around the HL_1M tokama k to mea sure the flux and dose of neutron radiation under the situations: the emission o f D_D fusion neutron being in deuterium plasma or the emission of photo_neutron being in hydrogen plasma. The results of measurement are compared with those of calculation, both agree roughly with each other. The dose equivalent of neutron radiation is very low, the measured value is far below the national and ministry issued standards of permissible dose equivalent.