Search

In this work, the solubilities of the salt minerals and the densities of solutions in two ternary systems, calcium chloride–zinc chloride–water and potassium chloride–zinc chloride–water, were measured at 373 K using an isothermal dissolution equilibrium method. Based on the determined equilibrium solubility data and the corresponding equilibrium solid phases, the phase diagrams and density diagrams of the two systems were plotted. The results show that the two ternary systems are complex. The invariant points, the univariant solubility curves and the solid crystalline phase regions are reported and discussed. The phase diagram of the ternary CaCl2–ZnCl2–H2O system at 373 K includes two invariant points, three univariant solubility curves and three solid crystalline phase regions corresponding to CaCl2·2H2O, CaCl2·ZnCl2·2H2O and ZnCl2. Also, the phase diagram of the ternary KCl–ZnCl2–H2O system at 373 K is constituted of two invariant points, three univariant solubility curves and three solid crystalline phase regions corresponding to KCl, 2KCl·ZnCl2 and ZnCl2. The influence of one of solute on the solubility of the ternary systems is also discussed in this work.

The detection results of qPCR for PCV3 in collected samples. (DOC 65Â kb)

AA differences of Spike (S) and Nucleocapsid (N) protein between CH/GD01/2015 and CH/GD02/2015. (DOC 42Â kb)

Sequence information of PDCoVs and other coronaviruses used in the present study. (DOC 106Â kb)

Growth of SiC nanowires in plasma-assisted hot filament chemical-vapor-deposition by using hexamethyldisiloxane (HMDSO) as the gas source is reported. The SiC nanowires (SiC-NWs) grew on Au-coated silicon substrate with core-shell structure, where the core consisted of polycrystalline SiC grains and the shell exhibited amorphous structure. The featured structures such as cones, polyhedrons, ball-liked particles were observed in the case without plasma assistance. The underlying mechanism for the growth of nanostructures was also discussed. The high chemical activity induced by the plasma process plays an important role in using monomer to generate nanostructure.

A method to determine excitation temperatures based on the optical emission spectroscopy (OES) and Fermi-Dirac distribution was set up, and the temperatures of pure-argon and mixed-gases at different pressures were investigated. In this way we set up a standard process to get the excitation temperatures of plasmas operated at atmospheric and sub-atmospheric pressures.

Usually, the electrical breakdown of dielectric barrier discharge (DBD) at atmospheric pressure leads to a filamentary non-homogeneous discharge. However, it is also possible to obtain a diffuse DBD in homogeneous form, called atmospheric pressure glow discharge (APGD). We obtained a uniform APGD in helium and in the mixture of argon with alcohol, and studied the electrical characteristics of helium APGD. It is found that the relationship between discharge current and source frequency is different depending on the difference in gas gap when the applied voltage is kept constant. The discharge current shows an increasing trend with the increased frequency when gas gap is 0.8 cm, but the discharge current tends to decrease with the increased frequency when the gas gap increases. The discharge current always increases with the increased applied voltage when the source frequency is kept constant. We also observed a glow-like discharge in nitrogen at atmospheric pressure.

The plasma characteristics have been investigated in situ by using optical emission spectroscopy (OES) and the Langmuir probe during hot cathode direct current discharge plasma chemical vapor deposition of diamond films. The changes of atomic H and CH radical in the ground state have been calculated quantitatively according to the results of OES and the Langmuir probe measurement as discharge current density varied. It is shown that atomic H and CH radicals both in the ground state and in the excited state increase with the enhancement of the discharge current density in the plasma. The electron density and CH emission intensity increase linearly with the enhancement of discharge current densities. The generation of different carbon-containing radicals is related to the elevation of electron temperature. Combining the growth process of diamond films and the diagnostic results, it is shown that atomic H in the excited state may improve the diamond growth efficiently, and the increase of electron temperature and density plays an important role in the increase of the deposition rate of diamond films.

Atmospheric pressure surface discharge is shown to have great prospects for a number of industrial applications. To acquire better results in application fields and considering that the study of the basic parameters including electron temperature and electron density is desirable, we develop an equivalent circuit model and the diagnostic techniques based on optical emission spectroscopy and electrical measurement in our laboratory. The electron temperature has been determined to be about 0.7 eV by a Fermi–Dirac model. The electron density has been calculated to be near 1010cm−3 from a time resolved electrical measurement (Ohmic heating method).

Silicon oxide films were deposited in electron cyclotron resonance-radio frequency dual hybrid plasmas using a mixture of HMDSO and oxygen as source gases, and optical emission spectroscopy was employed to investigate the gas phase species in the plasma. It is found that both the deposition rate and the chemical bonds of films are significantly affected by the radio frequency bias. The deposition rate is slightly increased when a low direct current self-bias is applied, and is reduced with the increasing self-bias due to strengthened ion bombardment. The ratios of O to Si in the films deposited under the bias frequency of 400 kHz are above 2∶1, nearly the same as that under 13.56 MHz. However, the content of carbon under 400 kHz bias is much higher than that under 13.56 MHz. The reason is that the application of the high frequency bias of 13.56 MHz not only strengthens ion bombardment on the material surface, but also induces the variations of the bulk plasmas including the increase of O atom density, while the main effect of the bias of 400 kHz is only to strengthen ion bombardment.

A knotted polymer chain passing through a pore is investigated by molecule dynamics method. In this paper, we take 31 knot as an example. It is found that, during the process of translocation, the size of the knot fluctuates until the knot is unknotted. In addition, the effect of the knot on the translocation velocity of the knotted chain is also discussed. For the given external force, the average translocation time τ satisfies the scaling relation:τ～N α, and the scaling exponent α increases with the external force f. For short knotted polymer chains, the average translocation time τ decreases when the external force f increases. However, for very long knotted polymer chains, the average translocation time τ increases when the external force f increases. In the meantime, the position of knot in a knotted polymer chain also affects the average translocation time τ strongly. The closer the knot approaches the first translocated monomer, the longer the average translocation time. This investigation can provide some insights into the translocation of knotted polymer chains (especially knotted DNA) through the nanopore, and help us understand the translocation behavior of biomacromolecules.