Effects of Combined Sorbitan Monolaurate Anti-Agglomerants on Viscosity of Water-in-Oil Emulsion and Natural Gas Hydrate Slurry

Hydrate plugging is the major challenge in the flow assurance of deep-sea pipelines. For water-in-oil emulsions, this risk could be significantly reduced with the addition of anti-agglomerants (AAs). Hydrates often form from water-in-oil emulsions and the measurement of emulsion and slurry viscosity constitutes the basis for the application of hydrate slurry flow technology. In this work, using a novel high-pressure viscometer, emulsion and slurry viscosity with different AAs for water content ranging from 5% to 30% was obtained. The viscosity-temperature curves of emulsions were determined and correlated. The variation of system viscosity during hydrate formation from water-in-oil emulsions was examined, the sensitivity of stable slurry viscosity to water cut and the effects of temperature on annealed slurry viscosity were investigated. The results indicated that the variation of viscosity during hydrate formation relies on the conversion ratio. It also implied that the sensitivity of slurry viscosity to change in its water cut or temperature was reduced with AA addition

Design and Optimization for a New Locomotive Power Battery Box

To solve the disadvantages of the low protection grade, high weight, and high cost of the existing locomotive power battery system, this study optimizes the existing scheme and introduces the design concept of two-stage protection. The purpose of the research is to improve the protection level of the battery pack to IP68, to optimize the sheet metal power battery box structure into a more lightweight frame structure, to simplify the cooling mode of the battery pack for natural air cooling, and to improve the battery protection level and maintain the heat exchange capability. In the course of the study, a design scheme with a two-stage protection function is proposed. The numerical model analyzes the self-load, transverse load, longitudinal load, mode, and fatigue, and optimizes the layout of the power tank cell. The optimized box model was physically tested and economically compared. The results show that: (1) The maximum load stress is 128.4 MPa, which is lower than 235 MPa, the ultimate stress of the box material, and the fatigue factor of the frame box structure is 3.75, which is higher than 1.0, and it is not prone to fatigue damage. (2) Under the low-temperature heating condition, the overall temperature rise of the battery pack is 4.3 °C, which is greater than 2.3 °C under the air conditioning heat dissipation scheme. Under the high-temperature charging condition, the overall temperature rise of the battery pack is 2.0 °C, and the temperature value is the same as the temperature rise under the air conditioning cooling scheme. Under the high-temperature discharge condition, the overall temperature rise of the battery pack is 3.0 °C, and the temperature value is greater than 2.1 °C under the air conditioning heat dissipation scheme. At the same time, the temperature rise under the three working conditions is less than the 15 °C stipulated in the JS175-201805 standard. The simulation results show that the natural airflow and two-stage protection structure can provide a good temperature environment for the power battery to work. (3) The optimized box prototype can effectively maintain the structural integrity of the battery cell in the box in extreme test cases, reducing the probability of battery fire caused by battery cell deformation. (4) The power battery adopts a two-stage protection design under the battery power level, which can simultaneously achieve battery protection and prevent thermal runaway, while reducing costs. The research results provide a new concept for the design of a locomotive power battery system. (5) The weight of the optimized scheme is 2020 kg, and the original scheme is 2470 kg; thus, the reduction in weight is 450 kg. Meanwhile, the volume of the optimized scheme is 1.49 m3, and the original scheme is 1.93 m3; thus, the reduction in volume is 0.44 m3

Design and Optimization for a New Locomotive Power Battery Box

To solve the disadvantages of the low protection grade, high weight, and high cost of the existing locomotive power battery system, this study optimizes the existing scheme and introduces the design concept of two-stage protection. The purpose of the research is to improve the protection level of the battery pack to IP68, to optimize the sheet metal power battery box structure into a more lightweight frame structure, to simplify the cooling mode of the battery pack for natural air cooling, and to improve the battery protection level and maintain the heat exchange capability. In the course of the study, a design scheme with a two-stage protection function is proposed. The numerical model analyzes the self-load, transverse load, longitudinal load, mode, and fatigue, and optimizes the layout of the power tank cell. The optimized box model was physically tested and economically compared. The results show that: (1) The maximum load stress is 128.4 MPa, which is lower than 235 MPa, the ultimate stress of the box material, and the fatigue factor of the frame box structure is 3.75, which is higher than 1.0, and it is not prone to fatigue damage. (2) Under the low-temperature heating condition, the overall temperature rise of the battery pack is 4.3 °C, which is greater than 2.3 °C under the air conditioning heat dissipation scheme. Under the high-temperature charging condition, the overall temperature rise of the battery pack is 2.0 °C, and the temperature value is the same as the temperature rise under the air conditioning cooling scheme. Under the high-temperature discharge condition, the overall temperature rise of the battery pack is 3.0 °C, and the temperature value is greater than 2.1 °C under the air conditioning heat dissipation scheme. At the same time, the temperature rise under the three working conditions is less than the 15 °C stipulated in the JS175-201805 standard. The simulation results show that the natural airflow and two-stage protection structure can provide a good temperature environment for the power battery to work. (3) The optimized box prototype can effectively maintain the structural integrity of the battery cell in the box in extreme test cases, reducing the probability of battery fire caused by battery cell deformation. (4) The power battery adopts a two-stage protection design under the battery power level, which can simultaneously achieve battery protection and prevent thermal runaway, while reducing costs. The research results provide a new concept for the design of a locomotive power battery system. (5) The weight of the optimized scheme is 2020 kg, and the original scheme is 2470 kg; thus, the reduction in weight is 450 kg. Meanwhile, the volume of the optimized scheme is 1.49 m3, and the original scheme is 1.93 m3; thus, the reduction in volume is 0.44 m3

Trends of hospitalisation for patients with liver cirrhosis in Ningxia, China: a cross-sectional study

Objective To evaluate the changing trends of hospitalisation for patients with liver cirrhosis between 2015 and 2019 by using hospitalisation summary records in Ningxia Hui Autonomous Region (NHAR), China.Design A cross-sectional study.Setting Hospitalisation summary records between 1 January 2015 and 31 December 2019 from 28 top-ranking hospitals in NHAR were extracted and rigorously analysed.Participants During the study period, hospitalisation records referring to liver cirrhosis were included. Records with missing data were excluded. A total of 16 566 patients with liver cirrhosis were included in this study.Outcome measures International Classification of Diseases codes, tenth version (ICD-10) and text-diagnoses were used to identify hospitalisation records referring to liver cirrhosis.Results Between 2015 and 2019, hospitalisation rates for liver cirrhosis declined from 8.38% to 5.57%. Chronic viral hepatitis accounted for almost 70% of all liver cirrhosis admissions; the remaining 30% of patients were admitted due to non-viral hepatitis cirrhosis (28.06%) and alcoholic cirrhosis (2.05%). The male-to-female hospitalisation rate ratio for liver cirrhosis was 2.57. The hospitalisation rate for workers with hepatitis cirrhosis was significantly higher than farmers (hospitalisation rate ratio (RR)=1.06, 95% CI 1.01 to 1.15, p<0.001); this was also the case for alcoholic cirrhosis (RR=5.23, 95% CI 3.34 to 8.20). However, the hospitalisation rate for workers with non-viral hepatitis cirrhosis was significantly lower than for farmers (RR=5.23, 95% CI 3.34 to 8.20, p<0.001). The hospitalisation rate increased in patients over the age of 30 years and reached a peak at the age of 45–50 years.Conclusions The hospitalisation rate for liver cirrhosis has declined over recent years and chronic viral hepatitis remains the major cause of liver cirrhosis in NHAR. Hospitalisation summary records can efficiently reflect the local changing trends of hospitalisation for liver cirrhosis and represent an efficient strategy for the surveillance of chronic disease

A Comparative Analysis of Bionic and Neutral Shoes: Impact on Lower Limb Kinematics and Kinetics during Varied-Speed Running

The running biomechanics of running shoes have been extensively investigated. However, there is limited knowledge about the use of bionic shoes compared to neutral shoes, along with the velocities involved in their use. The aim of this study was to examine the biomechanical alterations associated with various running velocities of bionic shoes. By removing different thicknesses of the forefoot section, bionic shoes created a more natural shape—close to that of a human foot. The study included 16 heel strike runners running at 10 km/h, 12 km/h and 14 km/h in bionic shoes and neutral shoes, respectively. A two-way ANOVA and SPM1d were employed for examining kinematic and kinetic differences. Regarding the results for the shoes, increased ROM was observed for the bionic shoes for the hip (p p p p = 0.042) also showed significant differences. Regarding the velocity results, hip ROM (p p = 0.018) increased, while knee ROM (p = 0.023) decreased. The interaction effects only existed in hip (p = 0.031) and ankle (p = 0.008) ROM. The results of this study suggested that the impact of running propulsion in the bionic shoes was minimal. However, with increased velocities, the bionic shoes demonstrated the ability to absorb more force, created a more stable training environment, and contributed to injury prevention for the hip and ankle joints

Experimental Study and Theoretical Analysis of Steel–Concrete Composite Box Girder Bending Moment–Curvature Restoring Force

A steel–concrete composite box girder has good anti-seismic energy dissipation capacity, absorbs seismic energy, and reduces seismic action. It is very suitable for high-rise and super high-rise mega composite structure systems, which is in accordance with the condition of capital construction. In order to accurately study the elastic–plastic seismic response of the composite structure, the restoring force model of the building structure is the primary problem that needs to be solved. Previous research shows that shear connection degree, force ratio, and web height–thickness ratio are the major factors that influence composite box girder bearing capacity and seismic behavior. In this paper, low cycle vertical load tests of four steel–concrete composite box girders were conducted with different shear connection degrees and ratios of web height to thickness. The seismic behavior of a steel–concrete composite box girder was analyzed in depth, such as the hysteresis law, skeleton curve, and stiffness degradation law, etc. The influence of the shear connection degree and ratio of web height to thickness on seismic performance of the steel–concrete composite box girder was investigated. A three-fold line model of the bending moment–curvature skeleton curve of composite box girders was established. On the basis of experimental data and theoretical analysis, the formula of positive and negative stiffness degradation of composite box girders was obtained. Furthermore, the maximum point orientation hysteresis model of the bending moment–curvature of steel–concrete composite box girders was established. The calculated results of the restoring force model agree well with the experimental results. The accuracy of the proposed method is verified. The calculation method of the model is simple and clear, convenient for hand calculation, and suitable for engineering applications

A Study on Preparation and Stabilizing Mechanism of Hydrophobic Silica Nanofluids

Nanofluids have increasingly drawn interest in recent years with their various applications in a number of fields. The method for the preparation of stable nanofluids is a key concern for extending the application of nanofluids. This study focuses on the effect of pH, dosage of surfactant (TX-100), and nanofluid concentration on the stability of a silica nanofluid. Particle size and zeta potential are two important factors to consider in evaluating the stability of the silica nanofluid. Results indicate that the stability of the silica nanofluid highly depends on pH, dosage of surfactant (TX-100), and nanofluid concentration. On the basis of these experiments, the best conditions for the preparation of a silica nanofluid are 0.1 wt. % for the concentration of silica nanoparticles and TX-100 and 10 for pH. A transparent and stable silica nanofluid can thus be obtained

Advances in the Metabolic Mechanism and Functional Characteristics of Equol

Equol is the most potent soy isoflavone metabolite and is produced by specific intestinal microorganisms of mammals. It has promising application possibilities for preventing chronic diseases such as cardiovascular disease, breast cancer, and prostate cancer due to its high antioxidant activity and hormone-like activity. Thus, it is of great significance to systematically study the efficient preparation method of equol and its functional activity. This paper elaborates on the metabolic mechanism of equol in humans; focuses on the biological characteristics, synthesis methods, and the currently isolated equol-producing bacteria; and looks forward to its future development and application direction, aiming to provide guidance for the application and promotion of equol in the field of food and health products

The Study of a Novel Nanoparticle-Enhanced Wormlike Micellar System

Abstract In this work, a novel nanoparticle-enhanced wormlike micellar system (NEWMS) was proposed based on the typical wormlike micelles composed of cetyltrimethylammonium bromide (CTAB) and sodium salicylate (NaSal). In order to strengthen the structure of wormlike micelles, silica nanoparticles are used to design the novel nanoparticle-enhanced wormlike micelle. The stability and morphologies of silica nanoparticles were studied by dynamic light scattering (DLS) and transmission electron microscopy (TEM) at first. After the formation of NEWMS, the rheological properties were discussed in detail. The zero-shear viscosity of NEWMS increases with the addition of silica nanoparticles. Dynamic oscillatory measurements show the viscoelastic properties of NEWMS. Through comparison with the original wormlike micelles, the entanglement length and mesh size of NEWMS are nearly unchanged, while the contour length increases with the increase of silica concentration. These phenomena confirm the enhanced influence of silica nanoparticles on wormlike micelles. The formation mechanism of NEWMS, especially the interactions between wormlike micelles and nanoparticles, is proposed. This work can deepen the understanding of the novel NEWMS and widen their applications