KINETIC FUNCTIONS IN MAGNETOHYDRODYNAMICS WITH RESISTIVITY AND HALL EFFECT

We consider a nonlinear hyperbolic system of two conservation laws which arises in ideal magnetohydrodynamics and includes second-order terms accounting for magnetic resistivity and Hall effect. We show that the initial value problem for this model may lead to solutions exhibiting complex wave structures, including undercompressive nonclassical shock waves. We investigate numerically the subtle competition that takes place between the hyperbolic, diffusive, and dispersive parts of the system. Following Abeyratne, Knowles, LeFloch, and Truskinovsky, who studied similar questions arising in fluid and solid flows, we determine the associated kinetic function which characterizes the dynamics of undereompressive shocks driven by resistivity and Hall effect. To this end, we design a new class of ＂schemes with eontroled dissipation＂, following recent work by LeFloch and Mohammadian. It is now recognized that the equivalent equation associated with a scheme provides a guideline to design schemes that capture physically relevant, nonclassical shocks. We propose a new class of schemes based on high-order entropy conservative, finite differences for the hyperbolic flux, and high-order central differences for the resistivity and Hall terms. These schemes are tested for several regimes of （co-planar or not） initial data and parameter values, and allow us to analyze the properties of nonclassical shocks and establish the existence of monotone kinetic functions in magnetohydrodynamics.

A Model-based Phenomenological Investigation of Char Combustion Kinetics through Thermogravimetry

Five coal char samples were burnt in thermobalance with ramp heating rate of 30 K/min. The pore structure of these char samples was studied through mercury intrusion method. Combined with the kinetic theory of gases, the data of surface area was used in fitting the results. As a result, the kinetic triplet was given. The analysis showed that five char samples share almost the same intrinsic activation energy of the overall reaction. The phenomenological implication of the derived combustion rate equation was given.

Machine Learning Kinetic Energy Functional for a One-Dimensional Periodic System

Kinetic energy(KE) functional is crucial to speed up density functional theory calculation. However, deriving it accurately through traditional physics reasoning is challenging. We develop a generally applicable KE functional estimator for a one-dimensional (1D) extended system using a machine learning method. Our end-to-end solution combines the dimensionality reduction method with the Gaussian process regression, and simple scaling method to adapt to various 1D lattices. In addition to reaching chemical accuracy in KE calculation, our estimator also performs well on KE functional derivative prediction. Integrating this machine learning KE functional into the current orbital free density functional theory scheme is able to provide us with expected ground state electron density.

Effect of Jisuikang(脊髓康) on Kinetic Dysfunction in Patients after Spinal Injury

Objective： To explore the effect of Jisuikang （脊髓康, JSK） on kinetic dysfunction in patients after spinal injury. Methods： Eighty-four patients with spinal injury were assigned equally, according to a randomizing digital table to the treated group and the control group. Conventional treatment was given to both groups, and JSK was additionally given to the treated group. Changes of various kinetic function concerning parameters including kinetic score, grades of spinal injury, effectiveness of the treatment and available recovery rate in patients allocated in the treated group and the control group were observed and compared in the way issued by Association of Spinal Injury of America （ASIA）. Results： Better effects were shown in the treated group than those in the control group in improving kinetic score （92.00 ± 9.95 scores vs 83.76 ± 24.12 scores）, ASIA overall improvement rate （69.05% vs 45.24%） and grades of effectiveness （P〈0.05）. However, the difference of available recovery rate between the two groups was insignificant （P〉0.05）. Cenclusien： JSK could prevent secondary alteration of spinal injury, promote the recovery and regeneration of nerve tissues, but could not restore the function of a necrotic spine.

Dynamics of CO_2 Emission and Biochemical Properties of a Sandy Calcareous Soil Amended with Conocarpus Waste and Biochar

Biochar is a carbon-rich product obtained by biomass pyrolysis and considered a mean of carbon sequestration. In this research, a sandy calcareous soil from the Farm of the College of Food & Agriculture Sciences, King Saud University, Saudi Arabia, was amended with either woody waste of Conocarpus erectus L.(CW) or the biochar(BC) produced from CW at rates of 0(control), 10, 30 and 50 g kg-1. The effects of the amendments on soil p H, dissolved organic carbon(DOC), microbial biomass carbon(MBC), CO2 emission and metabolic quotient(q CO2) of the sandy calcareous soil were studied in a 60-d incubation experiment. The results showed that the addition of CW led to a significant decrease in soil p H compared to the control and the addition of BC. The CO2-C emission rate was higher in the first few days of incubation than when the incubation time progressed. The cumulative CO2-C emission from the soil amended with CW, especially at higher rates, was higher(approximately 3- to 6-fold) than that from the control and the soil amended with BC. The BC-amended soil showed significant increases in CO2-C emission rate during the first days of incubation as compared to the non-amended soil, but the increase in cumulative CO2-C emission was not significant after 60 d of incubation. On the other hand, CW applications resulted in considerably higher cumulative CO2-C emission, MBC and DOC than the control and BC applications. With the exception of 0 day(after 1 h of incubation), both CW and BC applications led to lower values of q CO2 as compared to the control. The power function kinetic model satisfactorily described the cumulative CO2-C emission. Generally, the lowest values of CO2 emission were observed in the soil with BC, suggesting that the contribution of BC to CO2 emission was very small as compared to that of CW.