Transmission of dipolar substituent effects: ionization of a series 3-(7-substituted-1-naphthyl) propynoic acid (E)-3-(7-substituted-1-naphthyl) propenoic acids and their Esterification with Diazodiphenylmethane

Alkaline hydrolysis rates coefficients for the series of methyl 3-(7-substituted-1-naphthyl) propynoate was calculated in 70%v/v dimethylsulphoxide-water at various temperatures (25,30,40, and 50̊ C). The pKa values of 3-(7-substituted-1-naphthyl) propynoic acid and (E)- 3-(7-substituted-1-naphthyl) propenoic acid calculated in 80%w/w 2-methoxyethanol-water at room temperature (25.0̊ C). logk2 of esterification rate coefficients for 3-(7-substituted-1-naphthyl) propynioc acid and (E)-3(7-substituted-1-naphthyl) propenioc acid with DDM have been measured at 30.0̊ C. Reversed substituent dipolar effects were found in the ionization reaction. In the esterification reaction with DDM the result show similar but reduced substituted effects. Rate retardations was found in the alkaline hydrolysis. It could be result from steric effect or reversal of substituent dipolar effect with a combination of steric effect.

Optical Properties of C−rich (12C, SiC and FeC) Dust Layered Structure of Massive Stars

The composition and structure of interstellar dust are important and complex for the study of the evolution of stars and the interstellar medium (ISM). However, there is a lack of corresponding experimental data and model theories. By theoretical calculations based on ab-initio method, we have predicted and geometry optimized the structures of Carbon-rich (C-rich) dusts, carbon (12C), iron carbide (FeC), silicon carbide (SiC), even silicon (28Si), iron (56Fe), and investigated the optical absorption coefficients and emission coefficients of these materials in 0D (zero−dimensional), 1D, and 2D nanostructures. Comparing the nebular spectra of the supernovae (SN) with the coefficient of dust, we find that the optical absorption coefficient of the 2D 12C, 28Si, 56Fe, SiC and FeC structure corresponds to the absorption peak displayed in the infrared band (5−8) µm of the spectrum at 7554 days after the SN1987A explosion. And it also corresponds to the spectrum of 535 days after the explosion of SN2018bsz, when the wavelength in the range of (0.2−0.8) and (3−10) µm. Nevertheless, 2D SiC and FeC corresponds to the spectrum of 844 days after the explosion of SN2010jl, when the wavelength is within (0.08−10) µm. Therefore, FeC and SiC may be the second type of dust in SN1987A corresponding to infrared band (5−8) µm of dust and may be in the ejecta of SN2010jl and SN2018bsz. The nano−scale C−rich dust size is ∼ 0.1 nm in SN2018bsz, which is 3 orders of magnitude lower than the value of 0.1 µm. In addition, due to the ionization reaction in the supernova remnant (SNR), we also calculated the Infrared Radiation (IR) spectrum of dust cations. We find that the cation of the 2D layered (SiC)2+ has a higher IR spectrum than those of the cation (SiC)1+ and neutral (SiC)0+.

Experimental Study of the Effect of Plasma Cutting on the Tensile Strength of Materials "Fe"

The cutting process in plasma cutting begins with the formation of a pilot arc between the electrode and the workpiece as a result of the electrical ionization reaction of the highly conductive cutting gas. The gas is heated by the pilot arc until its temperature rises very high then the gas will be ionized and become a conductor of electricity. When the gas stream leaves the nozzle, the gas expands rapidly carrying the molten metal so that the cutting process continues. This plasma temperature can reach 33,000°C, approximately 10 times the temperature produced by the reaction of oxygen and acetylene. If this is related to the mechanical properties of the material, where the material has been heated it will result in changes in the mechanical properties of the material in the heating area/around the cutting plane. Tensile testing is the most widely used type of test because it is able to provide representative information on the mechanical behavior of the material. Seeing an incident like this, it is necessary to test the Effect of Plasma Cutting on the Tensile Strength of 'Fe' Materials through a tensile test. Several studies have shown that torch height, amperage and cutting speed can affect material properties. The best tool parameter settings are obtained at a travel speed of 500 mm/min, 75 amperes and a torch-material distance of 3 mm so that these settings are used as a reference in this study. In analyzing the data, the authors compare the results of plasma cutting testing with conventional cutting, in order to know the changes in mechanical properties that occur.

Effect of non-ionizing reaction rate (assumed to be controllable) on the plasma generation mechanism and communication around RAMC vehicle during atmospheric reentry

Radio frequency (RF) blackout occurs during radio attenuation measurement C (RAMC) vehicle reentry due to the attenuation effect of the plasma sheath on the communication signal. In recent years, the mitigation mechanism of chemical reaction for RF blackout problem has gradually been studied numerically and experimentally. However, the effect of non-ionization reaction rate has been ignored because it does not directly involve the generation of electrons. In the present study, the influence of non-ionizing reaction rate on the plasma generation mechanism and EM wave attenuation was numerically solved by the plasma flow and multilayer transmission model. According to the simulation results, only the reaction rate of $$NO \rightleftharpoons N + O$$ N O ⇌ N + O has a significant effect on the electron number density in all non-ionizing reactions, and the degree of influence is less than the ionization reaction rate. The EM wave attenuation decreases with the decrease of the reaction rate of $$NO \rightleftharpoons N + O$$ N O ⇌ N + O . When the reaction rate is reduced by 25 times, the maximum attenuation of electromagnetic wave can be reduced by 12 dB. Finally, a potential scheme by reducing the reaction rate of $$NO \rightleftharpoons N + O$$ N O ⇌ N + O was proposed to mitigate the RF blackout problem.

Evaluation of the Pr + O → PrO+ + e− chemi-ionization reaction enthalpy and praseodymium oxide, carbide, dioxide, and carbonyl cation bond energies

Guided ion beam tandem mass spectrometry was used to measure the kinetic energy dependent product ion cross sections for reactions of the lanthanide metal praseodymium cation (Pr+) with O2, CO2, and CO and reactions of PrO+ with CO, O2, and Xe.

Pharmacokinetics study of potential anti-CML drug Cyclobentinib (CB1107) by HPLC–MS/MS

Purpose: A simple, sensitive and specific HPLC–MS/MS method was established to analysis the pharmacokinetics of CB1107 in mouses. Methods: A simple, selective, and sensitive high-throughput liquid chromatography-tandem mass spectrometry (LC-MS-MS) method has been developed and validated for quantitative determination of CB1107 in rat serum.Chromatographic separation was achieved on a Zorbax Extend C18 Rapid Resolution HD column (4.6 mm × 50 mm, 1.8 μm). The column temperature was maintained at 35℃ and at flow rate of 0.6 mL/min. Injection volume was 20 μL. The mobile phases consisted of 0.1% formic acid in water (mobile phase A)and 0.1% formic acid in acetonitrile (mobile phase B), and total run time was 30min. MS-MS detection was performed in the selected monitoring mode of electrospray positive ionization reaction. Results: The pharmacokinetic characteristics of CB1107 in mice belong to the two-compartment model.When the doses were 400 mg/kg, 600 mg/kg and 800 mg/kg, corresponding area under the plasma concentration-time curve (AUC) respectively were 20.011±1.24 mg/h/L, 26.778±2.19 mg/h/L, 38.82±1.44 mg/h/L, suggesting that CB1107 have a good absorption in the body.And the AUC of three doses are proportional, indicating that CB1107 conforms to linear pharmacokinetics in vivo. Conclusion: This method was successfully applied to study the pharmacokinetics at three different doses of CB1107 after oral administration in mouses. In this study, the bioactivity mechanism of CB1107, by the pharmacokinetic investigation of CB1107 in vivo.