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The in-situ mixing zone represents dynamic characteristics of CO2 miscible displacement flows, which is important for carbon dioxide enhanced oil recovery (CO2-EOR) projects. However, the migration characteristics of the in-situ mixing zone under reservoir conditions has been neither well studied nor fully understood. The in-situ mixing zone with the flowing mixture of supercritical CO2 and n-decane (nC10) was investigated by using a magnetic resonance imaging apparatus at a reservoir condition of 8.5 MPa and 37.8 °C in porous media. The experimental results showed that the CO2-frontal velocity was larger than the mixing-frontal velocity. The mixing zone length was linearly declined in the miscible displacement process. And the declining rate of the mixing zone length was increased with injection rate. It indicates that the mixing zone length is not constant in a vertically stable CO2 misible displacement and a volume contraction due to phase behavior effects may occur. Then, an error function based on the convection-dispersion equation was fitted with CO2 miscible displacement experiments. The error function was well fitted both at a series of fixed core positions and a series of fixed displacement times. Furthermore, the longitudinal dispersion coefficients (Klx and Klt) and the longitudinal Peclet numbers (Ped and PeL) were quantified from the fitting results. The evolutions of the longitudinal dispersion coefficient were reduced along the displacement time. And the declining rate was increased with injection rate. And with proceeding, the longitudinal dispersion coefficient was tending towards stability and constant. But the evolutions of the longitudinal Peclet numbers were increased along the displacement time. And the increasing rate was increased with injection rate. [ABSTRACT FROM AUTHOR]

Background. Spinal fibroblastic and myofibroblastic tumors (FMTs) are extremely rare. Few studies have reported on the features and outcomes of this condition that affects the axial skeleton. We explored the clinical characteristics and factors affecting the prognosis of spinal FMTs. Methods. We retroactively assessed the survival of 51 patients with spinal FMTs who underwent surgical and adjuvant treatments in our center between April 2006 and September 2018. Factors affecting disease-free survival (DFS) and overall survival (OS) were analyzed using the Kaplan--Meier method. Variables with p value = 0.05 were subjected to multivariate analysis using the Cox proportional hazards regression model. A two-sided P value < 0.05 was considered statistically significant. Results. The mean follow-up period was 50.8 ± 35.6 months (Range 4.2=172.6). Kaplan-Meier survival curves showed that the 5-year DFS was 10% (95% CI [31.09-42.56]) and the 5-year OS was 53% (95% CI [61.28-97.20]). Multivariate analysis showed that en bloc excision was associated with better DFS (HR 0.214, 0.011) and OS (HR 0.273, 0.043), radiotherapy negatively affected OS (HR 0.353, 0.033), and the recurrence and Ki-67 index<5% significantly affected DFS (HR 3.008, 0.008 and 2.754, 0.029). Conclusions. Spinal FMTs are rare. Surgery is the treatment of choice and en bloc excision is strongly recommended to improve outcomes. Disease recurrence and the Ki-67 marker are correlated with the progression of these tumors. [ABSTRACT FROM AUTHOR]

The detection of electromagnetic radiation (EMR) during the fracture of solid materials such as rocks and coal has been widely used in seismic exploration and mine dynamic disaster prediction. As described in this paper, we conduct uniaxial compression tests on coal, cement, and glass materials to determine the characteristic EMR differences among materials. A band-stop filter based on the Fourier transform and the wavelet packet transform method are used to conduct signal denoising and analysis. Basic analyses of the pulse-time characteristics, energy distribution, cumulative energy, and waveform characteristics of EMR are conducted. The research results show that there is a strong corresponding relation between the loading time, loading stress and EMR energy. A large number of EMR events are released in rapid succession during the main rupture of coal and cement, while the EMR events are evenly distributed throughout the whole loading process of glass. For the same material, the maximum EMR amplitude increases with an increasing peak value of the stress. The EMR pulse waveform of coal and cement agrees well with predictions based on the theoretical formula of the electromagnetic dipole oscillation EMR generation mechanism. The paper provides further theoretical basis for understanding the mechanism of EMR, with great significance for improving coal mining safety. [ABSTRACT FROM AUTHOR]

The article looks at a study regarding the dual suppression of estrogenic and inflammatory activities for targeting of endometriosis. It mentions development of estrogen receptor (ER) ligands, chloroindazole (CLI) and oxabicycloheptene sulfonate (OBHS), which showed strong ER-dependent anti-inflammatory activity in a preclinical model of endometriosis. It also mentions Estrogen-dependent phenomena such as cell proliferation, cyst formation, vascularization, and lesion growth.

Studies the activation volume for boron diffusion in silicon and implications for strained films. Results for hydrostatic pressure; Effects of biaxial strain on diffusion.

The quasi-zero stiffness(QZS) nonlinear isolators have been paid much attention in recent literatures due to their excellent vibration isolation performance under low frequency excitation compared to traditional linear vibration isolators. However, passive QZS isolators are the most widely studied and they are incapable of dealing with varying conditions such as changing the excitation frequency or load in operating state. To promote the adaptability of QZS isolators, a novel approach to achieve real-time controllable QZS is proposed in this paper. An electromagnetic negative stiffness unit comprised of two electromagnet with MR elastomer is employed to produce negative stiffness, and the stiffness characteristic of the system can be accurately controlled by adjusting the driving current according to the displacement information in real time. Theoretical calculation and finite element analysis is conducted to establish the exact model of electromagnetic force followed by the general design of the system. Then a customized driver is developed for electromagnetic negative stiffness unit, and the dynamic model of the isolator is set up to study the effect of relative parameters on the transmissibility. Finally, a series of experiments are performed to evaluate the real-time controllable QZS characteristic and confirm the vibration isolation effect of the proposed electromagnetic QZS isolator. [ABSTRACT FROM AUTHOR]