An Experimental Analysis of Gas-Liquid Flow Breakdown in a T-Junction

When a gas-liquid two-phase flow(GLTPF)enters a parallel separator through a T-junction,it generally splits unevenly.This phenomenon can seriously affect the operation efficiency and safety of the equipment located downstream.In order to investigate these aspects and,more specifically,the so-called bias phenomenon(all gas and liquid flowing to one pipe,while the other pipe is a liquid column that fluctuates up and down),laboratory experiments were carried out by using a T-junction connected to two parallel vertical pipes.Moreover,a GLTPF prediction model based on the principle of minimum potential energy was introduced.The research results indicate that this model can accurately predict the GLTPF state in parallel risers.The boundary of the slug flow and the churn flow in the opposite pipe can be predicted.Overall,according to the results,the pressure drop curves of the two-phase flow in the parallel risers are basically the same when there is no bias phenomenon,but the pressure drop in the parallel riser displays a large deviation when there is a slug flow-churn flow.Only when the parallel riser is in a state of asymmetric flow and one of the risers produces churn flow,the two-phase flow is prone to produce the bias phenomenon.

Three-dimensional stability calculation method for high and large composite slopes formed by mining stope and inner dump in adjacent open pits

The 2D limit equilibrium method is widely used for slope stability analysis.However,with the advancement of dump engineering,composite slopes often exhibit significant 3D mechanical effects.Consequently,it is of significant importance to develop an effective 3D stability calculation method for composite slopes to enhance the design and stability control of open-pit slope engineering.Using the composite slope formed by the mining stope and inner dump in Baiyinhua No.1 and No.2 open-pit coal mine as a case study,this research investigates the failure mode of composite slopes and establishes spatial shape equations for the sliding mass.By integrating the shear resistance and sliding force of each row of microstrip columns onto the bottom surface of the strip corresponding to the main sliding surface,a novel 2D equivalent physical and mechanical parameters analysis method for the strips on the main sliding surface of 3D sliding masses is proposed.Subsequently,a comprehensive 3D stability calculation method for composite slopes is developed,and the quantitative relationship between the coordinated development distance and its 3D stability coefficients is examined.The analysis reveals that the failure mode of the composite slope is characterized by cutting-bedding sliding,with the arc serving as the side interface and the weak layer as the bottom interface,while the destabilization mechanism primarily involves shear failure.The spatial form equation of the sliding mass comprises an ellipsoid and weak plane equation.The analysis revealed that when the coordinated development distance is 1500 m,the error rate between the 3D stability calculation result and the 2D stability calculation result of the composite slope is less than 8%,thereby verifying the proposed analytical method of equivalent physical and mechanical parameters and the 3D stability calculation method for composite slopes.Furthermore,the3D stability coefficient of the composite slope exhibits an exponential correlation with the coordinated development distance,with the coefficient gradually decreasing as the coordinated development distance increases.These findings provide a theoretical guideline for designing similar slope shape parameters and conducting stability analysis.

Exploring the mechanism of active ingredients of Smilacis Glabrae Rhizoma in treating migraine headache through network pharmacology and animal experiments

Background:To explore the potential mechanism of action of the active ingredients of Smilacis Glabrae Rhizoma(SGR)in the treatment of migraine using network pharmacology and in vivo experiments.Methods:Through the search of Traditional Chinese Medicines Systems Pharmacology Database and Analysis Platform,Genecards,Drugbank and other databases,we obtained active ingredients,targets of SGR and related disease targets of migraine,and took the intersection for protein-protein interactions analysis.After constructing the network diagram,network topology analysis was performed to derive the core targets and key active ingredients,and Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed.Finally,molecular docking was performed and validated by in vivo experiments.In vivo experiments,18 male BALB/c mice were selected,and the SGR group was fed with SGR drinking tablet concentrate,and nitroglycerin injection was used to construct a mouse model of migraine.Enzyme-linked immunosorbent assay test was used to detect the levels of TNF-α,IL-1β,IL-6,and AKT1 in plasma.Results:The results showed that the core targets of SGR for the treatment of migraine were TNF-α,IL-1β,IL-6,and AKT1.These core targets and key active ingredients had better binding ability.Compared with the blank group,the number of head scratching in the model group increased.Compared with the model group,there was a significant reduction of the number of head scratching in the SGR group.In comparison with the blank group,the protein level in the plasma in the model group was markedly higher.Compared with the model group,the protein level in the SGR group was significantly lower.Conclusion:SGR has the characteristics of improving migraine based on multi-targets,multi-components and multi-pathways,and the mechanism of action may be related to the inhibition of the release of inflammatory factors,neuron protection,and interference with apoptosis and other processes.

Effect Mechanisms of Hygrothermal Environments on Failure of Single-Lap and Double-Lap CFRP-Aluminum Bolted Joints

The high demands for load-carrying capability and structural efficiency of composite-metal bolted joints trigger in-depth investigations on failure mechanisms of the joints in hygrothermal environments.However,few studies have been presented to exhaustively reveal hygrothermal effects on the failure of CFRP-metal bolted joints,which differ from CFRP-CFRP or metal-metal bolted joints because of the remarkably different material properties of CFRPs and metals.In this paper,hygrothermal effects on tensile failures of single-lap and double-lap CFRP-aluminum bolted joints were experimentally and numerically investigated.A novel numerical model,in which a hygrothermal-included progressive damage model of composites was established and elastic-plastic models of metals were built,was proposed to predict the failures of the CFRP-metal bolted joints in hygrothermal environments and validated by corresponding experiments.Different failure mechanisms of single-lap and double-lap CFRP-aluminum bolted joints,under 23°C/Dry and 70°C/Wet conditions,were revealed,respectively.It follows that both the collapse failures of the single-lap and double-lap bolted joints were dominated by the bearing failure of the CFRP hole laminate in the two conditions,indicating that the hygrothermal environment did not change the macro failure modes of the joints.However,the hygrothermal environment considerably shortened the damage propagation processes and reduced the strength of the joints.Besides,the hygrothermal environment weakened the load-transfer capability of the single-lap joint more severely than the double-lap joint because it aggravated the secondary bending effects of the single-lap joint obviously.

Effect of the Gut Microbiota on Obesity and Its Underlying Mechanisms: an Update

Obesity has become one of the most prevalent health issues of our time. According to a 2012 WHO report, around 3.4 million adults die each year as a result of being overweight or obese. Humans are in fact superorganisms composed of both human and microbial cells with 2 sets of genes, those encoded in our own genome and those encoded in our microbiota. All these cells and genes have the potential to influence our health.

MULTIPLE SCATTERING THEORY OF EFFECTIVE MECHANICAL PROPERTIES OF INHOMOGENEOUS MEDIA

The rate of hydrothermal reaction of SiO_2 and/or A1_2O_3 in the system of CaO-Al_2O_3-SiO_2-H_2O at 200℃ and the factors which influence the reactions are investigated by determining the reaction ratio.The rate of reactions depends on the reactive activities of raw materials, initial composition of mixture and relative activity of SiO_2 and A12O3. The hydrothermal reaction can be accelerated by sodium hydroxide,in the case of silica,which has low activity, this is quite obvious.

An Exploration of a Systematic and Effective Mechanism of Delivering Feedback on EFL Student Writing

In China, it is widely believed that teacher feedback plays a crucial role in EFL writing course, exerting a great impact on the improvement of Chinese EFL students＇ writing abilities so that teachers have been required to deliver feedback on students＇ writings. Teachers, consequently, spare no pains to give feedback, expecting their students would make progress in their writing, but it seems that things go contrary to their wishes. Although there are various complicated factors contributing to the situation, one of the important factors lies in the teachers, a number of whom do not grasp a systematic and effective mechanism of delivering feedback on EFL student writing. Much importance has been attached to Chinese EFL student writing, however, rare attention has been paid to conducting research on concrete ways of delivering feedback on Chinese EFL student writing in China. Therefore, this paper serves to fill the gap, mainly devoting itself to exploring concrete methods of delivering teacher feedback on EFL student writing.

Quantum Boltzmann equation solved by Monte Carlo method for nano-scale semiconductor devices simulation

A two-dimensional （2D） full band self-consistent ensemble Monte Carlo （MC） method for solving the quantum Boltzmann equation, including collision broadening and quantum potential corrections, is developed to extend the MC method to the study of nano-scale semiconductor devices with obvious quantum mechanical （QM） effects. The quantum effects both in real space and momentum space in nano-scale semiconductor devices can be simulated. The effective mobility in the inversion layer of n and p channel MOSFET is simulated and compared with experimental data to verify this method. With this method 50nm ultra thin body silicon on insulator MOSFET are simulated. Results indicate that this method can be used to simulate the 2D QM effects in semiconductor devices including tunnelling effect.

Effects of signal regulatory proteinα1 on proliferation of hepatocellular carcinoma: a preliminary study

BACKGROUND: Signal regulatory protein alpha1 (Sirpα1) is a negative regulatory factor, and inhibits receptor tyro- sine kinase-dependent cell proliferating signal. This study was undertaken to observe the effect of signal regulatory proteinα1 ( Sirpα1) on gankyrin, cyclin D1, CDK4 and Fas expression in Sk-hep1 mouse hepatoma carcinoma cell line. METHODS: BOSC 23 packed cells were respectively trans- fected by means of recombinated retrovirus including pLX- SN, pLXSN-Sirpα1 and pLXSN-Sirpα1Δ4Y2 with lipofec- tin, and various plasmid virus media (viral titer 2.1 × 106 CFU/ml) were collected and infected respectively in 80% confluent Sk-hepl cells. Transfected Sk-hep1 cells were se- lectively screened with G418 (1200 μg/ml), and Sk-hep1 cell lines transfected with various plasmids were obtained. The protein expressions of gankyrin, cyclin D1, CDK4 and Fas in various Sk-hep1 lines were determined by Western blotting. Various Sk-hep1 lines were recovered to culture with 10% fetal bovine serum at 12 hours and 24 hours after starving culture with free serum for 72 hours, and cells were collected to determine the percentage of S phase cells of proliferating cycle by flow cytometry. RESULTS: Sirpα1 transfection remarkably downregulated gankyrin and cyclin D1 expression. Sirpα1Δ4Y2 downregu- lation of gankyrin expression was greater than that of Sirpα1(P <0.05), but no significant effect of Sirpα1 and Sirpα1Δ4Y2 on CDK4 and Fas protein expression was ob- served in transfected Sk-hep1 lines (P >0.05). The per- centage of S phase cells significantly decreased in Sk-hep1 cells transfected with Sirpα1 and Sirpα1Δ4Y2 plasmids (vs pLXSN Sk-hep1, P <0.05). The percentage of S phase cells in various Sk-hep1 cells increased when recovering to culture with 10% fetal bovine serum at 12 hours, but the percentage of S phase cells in Sk-hep1 cells transfected with Sirpα1 was the lowest ( vs pLXSN and Sirpα1Δ4Y2 Sk- hepl, P<0.05). The percentage of S phase cells in trans- fected pLSXN Sk-hep1 cells was the largest (vs Sirpα1 and Sirpα1Δ4Y2 Sk-hepl, P <0. 05). There was no significant difference between the transfected Sirpα1 Sk-hepl cells and Sirpα1Δ4Y2 Sk-hep1 cells (P>0.05). CONCLUSIONS: Sirpα1 decreases gankyrin and cyclin D1 expression, and inhibits proliferation of liver carcinoma cells. It may be one of the forms for an Sirpα1 negative regulation of carcinogenesis and development of hepatocel- lular carcinoma.

Influence of air pressure on mechanical effect of laser plasma shock wave

The influence of air pressure on mechanical effect of laser plasma shock wave in a vacuum chamber produced by a Nd：YAG laser has been studied. The laser pulses with pulse width of 10ns and pulse energy of about 320mJ at 1.06μm wavelength is focused on the aluminium target mounted on a ballistic pendulum, and the air pressure in the chamber changes from 2.8 × 10^ 3 to 1.01 × 10^5pa. The experimental results show that the impulse coupling coefficient changes as the air pressure and the distance of the target from focus change. The mechanical effects of the plasma shock wave on the target are analysed at different distances from focus and the air pressure.

Characteristics and triggering mechanism of Xinmo landslide on 24 June 2017 in Sichuan, China

At 5: 39 AM on 24 June 2017, a huge landslide-debris avalanche occurred on Fugui Mountain at Xinmo village, Diexi town, Maoxian county, Sichuan province, China. The debris blocked the Songpinggou River for about 2 km, resulting in a heavy loss of both human lives and properties(10 deaths, 3 injuries, 73 missing, and 103 houses completely destroyed). The objectives of this paper are to understand the overall process and triggering factors of this landslide and to explore the affecting factors for its long term evolution before failure. Post event surveys were carried out the day after the landslide occurrence. Information was gathered from literature and on-site investigation and measurement. Topography, landforms, lithology, geological setting, earthquake history, meteorological and hydrological data of the area were analysed. Aerial photographs and other remote sensing information were used for evaluation and discussion. Eye witnesses also provided a lot of helpful information for us to understand the process of initiation, development and deposition. The depositional characteristics of the moving material as well as the traces of the movement,the structural features of the main scarp and the seismic waves induced by the slide are presented and discussed in detail in this paper. The results show that the mechanism of the landslide is a sudden rupture of the main block caused by the instability of a secondary block at a higher position. After the initiation, the failed rock mass at higher position overloaded the main block at the lower elevation and collapsed in tandem. Fragmentation of the rock mass occurred later, thus forming a debris avalanche with high mobility. This landslide case indicates that such seismic events could influence geological hazards for over 80 years and this study provides reference to the long term susceptibility and risk assessment of secondary geological hazards from earthquake.

Experimental Study on the Effect of Steel-fibre in Concrete Thick Cap

The effect of steel fibre used in concrete was systematically analyzed by model testing of 30 2-pile thick caps of steel-fibre reinforced concrete, in which the model scale was 1：5. The experiment system composed of a loading device, strain measurement system and a data-acquisition system was used, also an electromechanic centigrade scale, a lens and a Y J-25 static resistance strainometer were used.The experimental results show that the volumetric rate of steel fibre and draw ratio have an important influence on its load-bearing capacity. The incorporation of steel fibre can effectively improve the extension and reduce the thickness of the caps.

Effect of Irradiation on Crystallinity and Mechanical Properties of Ultrahigh-Molecular-Weight Polyethylene

Ultrahigh-molecular-weight polyethylene(UtlMWPE) has been irradiated (0-40 Mrad) with a Co^(60) source at room temperature under vacuum. Their crystallinity has been investigated by DSC and SAXS A significant increase of heat of fusion can be seen at low irradiation doses, which is attributed to crystallization caused by chain scission during the process of irradiation. It is also observed that thickness of lamellae changes with irradiation dose. Young's modulus has been improved significantly after irradiation at low doses.

Quantum-Mechanical Study on Surrounding-Gate Metal-Oxide-Semiconductor Field-Effect Transistors

As the channel length of metal-oxide-semiconductor field-effect transistors （MOSFETs） scales into the nanometer regime, quantum mechanical effects are becoming more and more significant. In this work, a model for the surrounding-gate （SG） nMOSFET is developed. The SchrSdinger equation is solved analytically. Some of the solutions are verified via results obtained from simulations. It is found that the percentage of the electrons with lighter conductivity mass increases as the silicon body radius decreases, or as the gate voltage reduces, or as the temperature decreases. The eentroid of inversion-layer is driven away from the silicon-oxide interface towards the silicon body, therefore the carriers will suffer less scattering from the interface and the electrons effective mobility of the SG nMOSFETs will be enhanced.

Analytical Modeling of Source-to-Drain Tunneling in Nanoscale Silicon MOSFET

Sub-10-nm bulk n-MOSFET （metal-oxide -semiconductor field effect transistor） direct source-to- drain tunneling current density using Wentzel- Krammers-Brillouin 0NKB） transmission tunneling theory has been simulated. The dependence of the source-to-drain tunneling current on channel length and barrier height is examined. Inversion layer quantization, band-gap narrowing, and drain induced barrier lowering effects have been included in the model. It has been observed that the leakage current density increases severely below 4 nm channel lengths, thus putting a limit to the scaling down of the MOSFETs. The results match closely with the numerical results already reported in literatures.

Effect of Surface Texture on Tensile Shear Strength of 1060Al-PET Welding Joints

Joining metal to plastic can lighten weight of products to reduce energy consumption.However,it is difficult to achieve high-strength welding between metal and plastic.To address this problem,the methods of surface texture pretreatment and laser irradiation welding was proposed to achieve the high-strength connection of metal and plastic.In this study,with different parameters of laser power and texture morphology,1060 Al with surface texture treatment was joined to polyethylene terephthalate(PET)by laser irradiation welding from metal side.Study showed that as the laser power increased,the tensile shear strength of joints increased first,and decreased thereafter.Tensile shear tests demonstrated that the mechanical force of joint was strengthened contributed to mechanical anchorage formed by surface texture.The depth-width ratio of the texture grooves affected the tensile shear process of the joint.According to the result of temperature simulation,the existence of texture grooves reduced the heat transfer efficiency,and the heat dissipation at interface was also impeded in course of laser welding.Finally,the maximum tensile strength of 1060Al-PET joint reached 48.4 MPa,which was close to the strength of PET matrix.The bonding mechanism of the 1060Al-PET joints was composed of mechanical bonding and chemical bonding.This study proposes an effective method to join metal to plastic which achieved high-strength connection between metal and plastic.

Protective Effects of Ginsenoside Rb1 on Septic Rats and Its Mechanism

This study aims to observe the protective effects of ginsenoside Rbl on liver and lung in rats with septic shock and reveal its mechanism. Rats were randomly divided into three groups： sham, cecal ligation and puncture （CLP）, and CLP with ginsenoside Rb1. Then, the survival rate, arterial blood pressure, TLR4 mRNA, and TNF-α levels were determined. The liver and lung tissues were stained with hematoxylin-eosin （HE）. The overall survival rate of the Rb1 group was significantly higher than that of the CLP group. Mean arterial blood pressure went down in both the CLP and Rb1 groups after CLP, and there was a significant difference both in the sham and Rb1 groups when compared with the CLP group. The Rb1 treatment group had markedly lower TLR4 mRNA expression and TNF-a levels than the CLP group. In the CLP group, pathology showed swelling, degeneration, necrosis, and neutrophii infiltration in the liver and alveolar epithelial cells. However, in the Rb1 group, there was mild degeneration and slight neutrophil infiltration, but no obvious necrosis. Rb1 may improve the survival rate, ameliorate arterial blood pressure, and protect the liver and lung in septic shock rats by downregulating the expression of TLR4 mRNA and inhibiting the production of TNF-α.

Effect of Trace Sc and Zr on the Mechanical Properties and Microstructure of A1 Alloy 2618

An experimental 2618(Al-Cu-Mg-Fe-Ni) alloy added with trace Sc and Zr was prepared by ingot metallurgy (IM) method. The aging behavior of the alloy was studied by Vickers hardness measurement at 200℃ and 300℃. and the tensile properties of alloy specimens were measured at 20℃, 200℃, 250℃ and 300℃. The microstructure was observed by using optical microscope, SEM and TEM. It was found that the addition of Sc and Zr to 2618 alloy resulted in a primary Al_3(Sc,Zr) phase which could refine the grain because it acts as nuclei of heterogeneous crystallization in the melt during solidification. The secondary Al_3(Sc,Zr) particles were full coherent with matrix and had obvious precipitation hardening effect. They also made the S' phase precipitate more homogeneous. So the strength of alloy increases at both ambient and elevated temperatures without a decrease of ductility. The ductile fracture of alloy occurs by microvoid nucleation, growth and coalescence, so the microvoid coalescence is the dominant fracture mechanism.

Mechanism on the Effect of Al upon the γ→ε Martensite Transformation in the Fe-Mn Alloys

The structure of the solid solution treated and deformed Fe-25Mn-(0-3.11)Al-0.15C alloys was examined by means of metallograph and X-ray diffraction, which has confirmed that Al restrains the γ→ε transformation in the Fe-Mn alloys. The mechanism on the restraining effect of Al has been discussed on the basis of the efFect of Al upon the stacking fault energy in the Fe-Mn alloys.Aluminium increases thermodynamically the stability of the Fe-Mn austenite and the driving force limit necessitated to be overcome for the γ→ε transformation, because the thermodynamicalcalculation indicates that Al increases the stacking fault energy in the Fe-Mn alloys at 300 K.Al will decrease the number and the size for the ε-martensite nucleus according to the stacking fault mechanism of the ε-martensite nucleation

Effect of corporate social responsibility on creation of added value

In the process of financial management and operation, a firm should not only aim to maximize its shareholders' benefits, but also consider the interests of all stakeholders. Bearing social responsibility to each stakeholder to a certain extent and pursuing harmonious social development are fully consistent with the concept of China's building a harmonious socialist society. Furthermore, added value also reflects the idea of social responsibility Based on the relational contract theory, the paper divides stakeholders into staff and shareholders under relational contracts, creditors, suppliers and consumers under transactional contracts and governments and communities under special contracts. The paper details the effect mechanism of a firm's bearing social responsibilities to each stakeholder on the creation of added value respectively, and considers that corporate social responsibilities should be included in the system for creating added value to theoretically support firm managers to fulfill social responsibilities.