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The topic of this study is the thermodynamic properties, elastic properties and electronic structure of Mg2Si and Li-doped Mg2Si (Mg7Si4Li, Mg8Si3Li and Mg8Si4Li) by first principles based on density functional theory method. The analysis of lattice constants manifests that When Li is doped in Mg2Si, structure cell will generate lattice distortion, which can change lattice constants and total volumes. All the studied compounds are stable. However, the structure will be not as stable as Mg2Si, when Li is doped in. Intrinsic Mg2Si, exhibit the best stiffness and the strongest brittleness. Li-doped Mg2Si, can refine the brittleness but reduce the stiffness. Density of State, band structure, Mulliken electrons and electron density difference show that electrical conductivity is enhanced after Li doping in Mg2Si. Specially, Mg8Si3Li exhibits a worst stability and stiffness, a best plasticity and electroconductibility.

In this perspective, we outline that a space borne gravitational wave detector network combining LISA and Taiji can be used to measure the Hubble constant with an uncertainty less than 0.5% in ten years, compared with the network of the ground based gravitational wave detectors which can measure the Hubble constant within a 2% uncertainty in the next five years by the standard siren method. Taiji is a Chinese space borne gravitational wave detection mission planned for launch in the early 2030 s. The pilot satellite mission Taiji-1 has been launched in August 2019 to verify the feasibility of Taiji. The results of a few technologies tested on Taiji-1 are presented in this paper. Gravitational wave astronomy has opened the door to test general relativity and the effect of gravity in the Universe. The authors present the capabilities of an overlap between space gravitational wave detectors LISA and Taiji to constrain the Hubble constant to 0.5%, in 10 years, and what can be learned from the satellite pilot Taiji-1 launched in 2019.

The well-known Hencky solution is only applicable to the problem of deformation of the elastic circular membrane without initial stress under transverse uniformly-distributed loads. The problem considered here is a more general case: an initial tensile or compressive stress has been present in the initially flat circular membrane before the membrane is subjected to the transverse loads. The closed-form solution of the considered problem was presented and all the expressions obtained here for displacements, strains and stresses have the same form as those in the well-known Hencky solution. The initial stress plays an important role in the determination of numerical value of the integral constant controlling membrane equation. The solution obtained here can be regressed into the well-known Hencky solution when the initial stress is equal to zero, and it is therefore called extended Hencky solution.

Dynamic simulations of structures to determine their seismic performance is an essential part of civil engineering research. Time integrators of increasing sophistication has been elaborated over the last few decades to achieve higher order accuracy, unconditional stability, computational efficiency and high-frequency dissipation. This paper tries to extend 1-stage Rosenbrock-based integrator to an integrator of second-order accuracy without losing computational efficiency and unconditional stability. Initially, 1-stage Rosenbrock integrator is introduced and its order of accuracy is studied theoretically. According to accuracy analysis, a force term at the end of current step is considered, resulting a novel integrator of second-order accuracy. Moreover, the stability of the proposed method is studied by means of the energy method. To investigate its performance for nonlinear structures, numerical simulations are conducted on a shear-type structure including a pendulum.

A kind of channel type embedded part which has been disposed through extrusion forming new technology needed to extensive apply in engineering. Theoretical analysis and experimental research have been carried out on shear properties of bolt and one-way static pull-out performance of channel. Got the ultimate bearing capacity, deformation and failure mode, compared the results between test and finite element analysis, fit a formula for calculating the bearing capacity of channel. Experimental result shows that embedded parts working performance is good. It has higher strength than work load and the expected ultimate load according to the theoretical calculation. Meantime, specimens has relatively good ductility before failure. The test results have provided the experimental basis for the application of embedded parts in engineering.

In this article we achieve SDH communication network correlation analysis by the confidence fusion algorithm. We take the effect of the alarm topology relationship on the alarm timing relationship into the calculation process of confidence fusion algorithm .Thus it can get alarm correlation results more in line with objective facts. According to the correlation calculation results it forms the alarm correlation transactions, then applying the alarm correlation transactions to the alarm association rules mining. We compare the mining results with the traditional method based on sliding window. The experimental results show that the mining results are more effective after introducing the confidence fusion algorithm.

This paper presents a technology of sliding damping which could resist ground frost heaving. In the technology, setting the low-grade mortar bond of the upper and lower ring beams to achieve slip shock absorption, and setting the rubber beams to achieve shear deformation limiting. By rubber beam shear performance test, the shear strength of the rubber beam has been acquired. In the paper, the finite element software has been adopted to simulate the seismic performances of common wall and sliding damping wall structures under low cyclic reversed loading, the hysteretic curves between the bottom shear and the top displacement of the walls. The research results show that sliding damping ring beam has the very good function on dissipating seismic energy and reducing seismic action.

Systems of ODEs arising from transient structural dynamics generally exhibit high-frequency/low-frequency and linear/nonlinear behaviours of subsets of state variables. This paper resorts to the use of different time integrators with different time steps for subsystems, to tailor each method and its time step to the solution behaviour of the corresponding subsystem. Anovel partitioned integration method with the acceleration continuity is proposed whose velocity continuity is also ensured by means of the mass projection strategy. Both its stability and accuracy properties are examined through numerical analysis on Single-DoF split mass system.

WINEPI algorithm is kind of data mining technology that is widely used in alarm association rules mining. Based on the classic WINEPI algorithm, we apply event window instead of time window to improve the exploration result, meanwhile we use FP-Growth algorithm framework instead of Apriori algorithm framework , thus improving efficiency. Based on the alarm time attribute we find interesting alarm association rules further. Experiments show that compared with the classic WINEPI algorithm our improved approach have advantages in reducing the mining error rate and gaining more interesting alarm association rules.

With the development of curtain wall in super high-rise buildings which promoting the application of embedded part. In this paper, the experimental research on the tensile, shear properties of a kind of channel type embedded part which has been disposed through a hot extrusion forming new technology. The mechanical properties, deformation and damage form of embedded parts were investigated.Experimental results indicate that it has good mechanical properties and favorable deformation performance under tensile and shear loads in normal work. Under effect of tension, the circular anchor nail was pulled-off from channel and the bottom junction between square anchor nail and channel was tore were the main failure forms. Otherwise, when under the effect of shear, the bolts were sheared fracture. The results of experiment could provide experimental basis for channel embedded part with wide application in engineering.

The Proton Engineering Frontier Project developed a 13-MHz pulsed, RF cavity for heavy-ion implanter applications. Typically, slow changes in the room temperature and the mechanical vibrations of the vacuum device may be primary sources of disturbances, and the accelerating cavity of the implanter may not be able to operate at the resonance frequency owing to disturbance effects. We need a voltage-controlled oscillator phased-locked loop circuit to make a control system that could suppress the disturbance effects; thus, the accelerating gradient of the cavity always reached a peak level for a given input power and coupling. An analog-circuit-based RF-frequency-tracking system was developed. Next, we obtained the optimal control parameters for the key control components. Finally, we measured the system performance between an open loop and a closed loop. The key point of the system design is to control the driving frequency that is used to operate the RF source by keeping the phase at around 0 degrees with respect to the resonance peak of the cavity. The experimental results showed that the fluctuations of the control loop error signal were suppressed by about a factor of 10. The presented feedback loop is implemented as a standard proportional controller. The loop p-gain is 120 k.

In this paper, a new loading method able to subtly control the crack driving force for pressurized blister test was proposed. A theoretical study of the adhesion energy measurement for film/substrate interface using this loading method was presented. Problems considered include solving the exact volume under a circular blister and the elastic strain energy stored in a thin blistering film, determining the work done by the poured colored liquid as external force to the system and the elastic strain energy stored in the compressed air. A new formula of energy release rate was finally presented. A comparison between the work presented here and the existing work was made.

The Proton Engineering Frontier Project (PEFP) finished a radio-frequency (RF) implanter. Due to mechanical vibration and temperature slow change in environment, the resonance frequency of the implanter’s cavity always drift. For obtaining an optimized beam output performance, a digital frequency control system was designed to regulate the driver frequency for tracking the frequency variation of the cavity. This paper presents the frequency control scheme and digital algorithm implementations. Traditional analog parts, such as phase comparators, analog proportional-integral (PI) controllers, and voltage-controlled oscillator (VCO), in lieu of the above components, a software code was created. The control logic code was written in VHSIC hardware description language (VHDL) language and was implemented on a field programmable gate array (FPGA) board, which was hosted in a versa module europa (VME) mainframe. The main digital control units, including IQ sampling digital phase comparator, digital PI controller, and numerical controlled oscillator (NCO) units were introduced. The algorithm implementation of the control logic, the loop behavior simulation, and the low-level RF experimental test results will be presented.

Developing an analysis program and simulating the radiation damping effect in the infinite foundation and inputs ground motion rationally. The static and dynamic analysis of an intake tunnel for a nuclear power plant is performed with ANSYS based on some 2-D finite element models considering of structure-foundation interaction by Time-History Analysis. Aiming at different programs of two linings in tunnel, the stress and internal force distribution of the tunnel , the wall rocks and the lining is researched and analyzed, and the diagram of stress and internal force is drawn. The regularity obtained can provide the basis for the seismic response analysis and design of tunnels.

In the paper, the equation of stiff characteristic coefficient of shear wall structure with unidirectional wall frames was derived, the deformation characteristics of structure with different wall frames ratio and height were analyzed. Through pushover analysis, the seismic performance of structures were evaluated by interlayer displacement angle and plastic hinge development process. Under earthquake action, increase of wall frames ratio will make plastic deformation increase and maximum interlayer displacement floor move down.The bottom of structure is the weak region, the short wall limbs of wall frames are the weak structural vertical members. The research results show that the wall frames bring adverse effects on the structural seismic performance, so the different design meathods should be carried out according to the overturning moment proportion of wall frames.

Wenchuan earthquake of May 12, 2008 in Sichuan province is most destructive, the most widely spread, the most difficultly to disaster relief in recent decades in China. The earthquake relief and reconstruction work is also the fastest, to mobilize the widest range of input power in an action, creating a miracle of the world's earthquake relief and reconstruction. Those successful practices provided a valuable experience reference to other areas for fight against natural disasters and rebuild their homes. This article describes the damage of housing, roads, bridges and other engineering structures and landslides mudslides, dammed lakes and other geological hazards triggered by earthquakes; Outlines the effort of the rescue operation, including personnel search and rescue, road rehabilitation, caring for the wounded, people placement and soon; Summarizes the reconstruction strategies and policies, including with Chinese characteristics” counterpart support” reconstruction mode which means a province to help a county. In the end, the article discusses the earthquake relief and reconstruction experience and inspiration.

Nanomaterials are of great importance to improving mudcake quality, reducing lost circulation, enhancing borehole stability, and protecting reservoir. Some nanomaterials, including nanometer plugging materials, nano-sized MMH drilling fluids, nanocomposite super-short fibers, water-based film-forming drilling fluids, nano-based drilling fluid, and so on, are introduced, and all of them have significantly influence on reservoir protection. As a result, the application of nanomaterials in the field of reservoir protection is very useful for maintaining borehole stability and protecting reservoir.

In this paper ,the parameter study of the instantaneous spectrum model is transformed to that of strength envelope model and instantaneous frequency model, based on the real ground motion array data, the statistical analysis result of the parameter of multipoint ground motion at local sites indicate that the most parameters are associated with projection distance and soil layer thickness, and the regression model and the value selection of various parameters provided in this paper can also be used for the reference of artificial synthesis of multipoint ground motion.

In order to improve the seismic behavior of the rural masonry buildings and reduce the cost and be convenient for construction, a precast tie-column system was put forward, which was suitable for masonry buildings, constructed by fired common bricks or porous bricks. The uniaxial compression constitutive relation of brick masonry was used for simulating the precast tie-column. And this paper analyzed the difference of the seismic behavior of masonry walls which bearing different vertical compressive stress, and confined by cast-in-place tie-columns or precast tie-columns, and whether contain windows or not. The results show that the uniaxial compression constitutive relation used for simulating precast tie-column is reasonable and the seismic behavior of masonry walls confined by precast tie-columns is better than the wall without tie-colums, and equal to those confined by cast-in-place tie-columns.

There are two typical seismic damage characteristics to the masonry building with frame shear wall structure at first two stories, and the lateral stiffness ratio of the third storey to the second storey is one of the key factors mostly affecting the seismic performance of this kind of building. However, some factors are not considered sufficiently in current Chinese seismic codes. According to the theory of performance-based seismic design, the seismic performance of this kind of structure is analyzed in this paper by taking time-history analysis on models which with different storey stiffness ratios. The results show that when the lateral stiffness ratio controlled in a reasonable range, the upper masonry deformation can be ensured in a range of elastic roughly, and the bottom frame can be guaranteed to have sufficient deformation and energy dissipation capacity. Finally, according to the seismic performance characteristics of masonry building with frame shear wall structure at first two stories, especially the characteristics under strong earthquakes, a method of simplified calculation model for the upper masonry is discussed in this paper.

The seismic action effects of tower structures for ultra-high-voltage(UHV, upon 750KV) overhead transmission lines are much greater than those of 500KV and below, it is necessary to inspect the control load in structural design and specify the seismic design scope of tower structures for these UHV transmission lines. In this paper, the current regulations of seismic design and non-seismic design of tower structures for overhead transmission line were contrasted firstly; then, a series of typical towers including large-crossing towers and cup-towers at soft sites, on the zone of earthquake fortification intensity region of 8, were analyzed. The ratios of seismic action effects and wind load effects for characteristic value were calculated and the control load in structural design of tower structure was investigated. The results show that, although the height and the weigth of tower structures for UHV transmission lines are increasing, the control load in structural design is still the wind load on the zone of earthquake fortification intensity region of 8 and below.

Frame structure on a slope is a common kind of structure in a mountainous area. It can diminish the impact on environment, by avoiding to dug or fill the slope, using an opening platform, supported by beams and columns. Because the frame structure on a slope connects with the ground on different elevation level, it is evidently different from general frame structure in seismic design. Four sets of frame structure example on a slope sample are designed, with three opening floors connected with the ground on different elevation level, and three, six, nine, twelve upper floors correspondingly. The seismic responses characteristics of frames on a slope are studied in the paper from period, lateral deformation, seismic shear and so on, based on the analysis of the characteristics of frame structure on a slope. The main conclusions are as follows: the slope can enhance structural lateral stiffness to a certain extent; the opening floors connected with the ground on different elevation level, are not necessarily frail stories; the distribution of seismic force is uneven between the columns in the same floors which connect with the ground on different elevation level, and fixed columns undertake more than others, making them more fragile; the torsional effect is noticeable in the frame structure on a slope.

Research status of ground motion parameters of seismic appraisal for existing structures is analyzed. According to the theory of the probabilistic distribution of seismic intensity which fits Extreme Value Type Ш, the relation of multi-value seismic intensity to seismic basic intensity from different seismic hazard characteristic zone is studied in this paper. Under the principle of all the seismic actions of each fortification level have the same exceeding probability, the basic intensity for seismic assessment of buildings with different residual service lives is given to each zone. At last, after giving full consideration to the seismic hazard differences to different areas, the modification factors of seismic action of buildings at the three zones with different seismic hazard characters are given in this paper. At last, this paper provides a base for the structure designers to choose a rational seismic action during the seismic appraisal for existing structures.

Based on HHT method, the influences of site conditions and epicenter distance on non-stationarity of multidimensional ground motion were studied. Additionally, preliminary statistics were carried out on frequency characteristics of multidimensional ground motion under different site conditions. The analysis results showed that HHT method was more accurate in a quantitative description of frequency-domain non-stationarity of ground motion than zero-crossing rate method, and also can reflected the non-stationarity of multidimensional ground motion better.

2008 Wenchuan earthquake has showed that failure of masonry walls is one of the major causes of material damage and loss of human life due to seismic events. Therefore, study of masonry walls seismic behavior and development of effective and practical retrofitting schemes is an urgent need. So this work presents an experimental program that investigates in-plane seismic behavior of common types of shale masonry walls before and after retrofitting using epoxy resin injection technique. In this experimental study, the primary objective was to evaluate the efficiency of this retrofitting method on masonry walls. The results of this study shows that using epoxy resin injection technique increased the in-plane maximum strength, the ductility, the initial stiffness value, the stiffness, and the energy dissipated during all the loading stages, and decreased the ductility factor.

Based on the test and numerical analysis, the paper studied the constructional reinforcement of blast furnace foundation under the influence of concrete hydration and top temperature. The results indicate that constructional reinforcement should be thinner and have a small spacing. Stress concentration always appears around the corner and constraints of blast furnace foundation, where should be strengthened with constructional reinforcements. In order to prevent cracks caused by internal tensile stress during concrete hardening, it is necessary to place temperature reinforcement inside the foundation. Temperature effect should be considered at the circular area on top of blast furnace foundation and should be strengthened with constructional reinforcements.

This paper, based on the Chongqing urban small earthquake zoning, structure of ground calculation model to analysis soil seismic response , determined the design ground motion parameters , and with the current seismic code were compared ,for the general construction projects in Chongqing provides a reference for seismic design . At the same time, it’s of importance to disaster mitigation of other cities, sustainable social and economic development.

Al-Mg2Si composite has such advantages as low density, high elastic modules, simple manufacture technology and low cost. However, its strength and ductility need to be enhanced. Thus, the alloying element P was added to control the microstructure of Al-Mg2Si alloy and furthermore improve the mechanical properties of the composite. The experimental results show that the microstructure of the Al-Mg2Si alloys subjected to electromagnetic stirring can be significantly refined and the mechanical properties of the alloy get improved due to the addition of phosphorus. It is found that the best modification effect can be achieved when the adding amount of phosphorus is in the range from 0.7% to 1.1% and the holding time is about 15 minutes, and the mechanical properties of the Al-Mg2Si alloys get markedly enhanced.

Through the anti-bending performance of the normal section experiment on four complex high titanium heavy slag reinforcement concrete beams and two ordinary RC beams, we compare them with concrete strength and longitudinal reinforcement ratio as parameters, and explore the performance of complex high titanium heavy slag reinforcement concrete beams on supporting capacity, crack, stiffness and ductility. The results show that, under the same conditions designed, the performance of complex high titanium heavy slag reinforcement concrete beams on the cracking moment, ultimate moment, the average crack width, stiffness and ductility is better than that of ordinary RC beams, presenting a typical normal section destruction. The findings of the present study provides reference to the application of complex high titanium heavy slag concrete into engineer structuring.

Reinforced concrete frame-shear wall structure is a double resistance to lateral force system, in which the frames and shear walls work cooperatively and the distributive rule of the earthquake force varies with different earthquake actions. To ensure the frames bear the increasing earthquake shear force and play a role of second defense line due to the internal force re-distribution after the stiffness degradation of shear walls, the elastic design earthquake shear force of the frames should be adjusted. However the adjustment measures applied in Chinese code are proposed according to the design experiences of engineers and lack of the theoretical and computational analytical basis. Moreover, there is a dispute about ignoring the rule of the shear force redistribution along storey or not, it is necessary to further evaluate the rationality of the measures in the code. In this paper, based on a 3-D precise nonlinear frame-shear wall structure analysis model, the re-distributive rule of the internal force under strong earthquake was studied and the adjustment measures of earthquake force in the frames were checked. Finally, some design suggestions were proposed.

This work is related to the error analysis of the proton engineering frontier project (PEFP) beam lines. In order to evaluate the error e ects on the trajectory of the beam center, we used an error analysis code that included a rst-order perturbation of the translational and the rotational errors of the dipole and the quadrupole magnets in the beam lines. The distorted beam trajectory can be corrected by using corrector magnets. The speci cations of the correction dipoles are obtained by using an error correction algorithm that is included in the code.

A low-beta superconducting radio-frequency (RF) cavity has been designed to accelerate a proton beam at an energy above 100 MeV at 700 MHz in the linac of the Proton Engineering Frontier Project (PEFP) and its extended project. Each low-beta superconducting cavity is composed of 5 cells and has a fundamental power coupler (FPC) to transfer the RF power from the klystron to the proton beam. The performance of the superconducting cavity and the FPC may be limited due to electron multipacting on the walls of the cavity, in the coaxial line, or in the RF window. In order to predict and prevent multipacting harm to a PEFP low-beta cavity and a FPC, we used MultiPac 2.1 for Windows to research the multipacting behaviors in those RF structures. By calculating the multipacting electron trajectories, the threshold values for the occurring multipacting and the nal energy of the secondary electron, we identi ed the location of multipacting occurrence and the power threshold. A reasonable design was obtained to prevent multipacting in the FPC.

The present study aimed to determine whether restraint stress aggravates kidney injury caused by a crush injury through endoplasmic reticulum stress (ERS).In this study, Sprague-Dawley rat restraint stress, crush injury, and stressful injury models consisting of restraint stress and crush injury were established. An ERS inhibitor, Salubrinal (Sal), was administered intraperitoneally 30 minutes before induction of daily injury in the stressful injury group. At the end of the experimental procedures, plasma levels of noradrenaline and adrenaline, creatine phosphokinase, creatinine, and blood urea nitrogen were measured. Kidneys were harvested, and paraffin-embedded sections of kidney tissues were processed for hematoxylin-eosin staining and TUNEL assay to verify pathologic changes. Western blot was used to determine the protein levels of glucose-regulated protein 78, CCAAT/enhancer-binding protein-homologous protein, caspase 12, caspase 3, and MCP-1 in kidney specimens.Compared with crush injury, the most significant changes in kidney injury occurred in the stressful injury group, which was inhibited by Sal. The results suggested that restraint stress aggravates kidney injury caused by a crush injury, and the mechanism might involve ERS. Further study showed that double attacks induced a significant increase in the levels of glucose-regulated protein 78, CCAAT/enhancer-binding protein-homologous protein, caspase 12, and caspase 3, which was inhibited by Sal. The same changes were observed using the TUNEL assay. Double attacks also induced an increased expression of the proinflammatory cytokine, MCP-1, which was inhibited by Sal.Apoptosis and inflammation induced by ERS are important mechanisms by which restraint stress aggravates kidney injury caused by a crush injury.

To observe the effects of megsin gene transfection on the expressions of monocyte chemoattractant protein-1 (MCP-1) and intercellular adhesion molecule-1(ICAM-1).Mouse glomerular mesangial cells were cultured in high glucose medium, and then cell proliferation was measured by MTT assay at 12, 24 and 48 h respectively. The expressions of megsin, MCP-1 and ICAM-1 in mesangial cells were detected by immunocytochemical staining and Western blotting. The concentration of type IV collagen in the culture supernatant of mesangial cells was measured by ELISA.Under high glucose concentration, the expressions of megsin, MCP-1 and ICAM-1 increased; the concentration of type IV collagen in the cell supernatant was elevated as well; and mesangial cell proliferation was enhanced. After megsin gene transfection, the above changes were more significant, but were abated following megsin shRNA/transfection.Megsin gene can up-regulate the expressions of MCP-1 and ICAM-1, promote mesangial cell proliferation and mesangial extracellular matrix accumulation.