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In this work, investigation on the degradation behavior of 1.2 kV/52 A silicon carbide (SiC) power MOSFETs subjected to repetitive slow power cycling stress has been performed. Electric characteristics have been characterized periodically over the stress and the respective degradation mechanisms have also been analyzed. A comprehensive degradation analysis is further conducted after the aging test by virtue of the x-ray inspection system, scanning acoustic microscope, scanning electron microscope, emission microscope, etc. Experimental results reveal that both the degradation of the gate oxide on the chip-level and the degradation of the bond wire and solder layer on the package-level have emerged over the cyclic stress. Specifically, growths of threshold voltage (V th) and gate leakage current (I gss) are thought to be relevant with the degradation of gate oxide by SiC/SiO2 interface states trapping/de-trapping electrons on the chip-level, while the appearance of fatigue in the bond wire and the delamination of the solder layer imply the degradation on the package-level. This work may provide some practical guidelines for assessments of the reliability of SiC power MOSFETs in power conversion systems.

High density polyethylene (HDPE)/kaolin composites with different hindered Amine light stabilizers were prepared by blending granulation. The mechanical properties and dynamic thermodynamic changes before and after aging were discussed and studied. The precipitates were analyzed by FI-IR and H1-NMR, and the precipitation reason and anti-aging difference of different light stabilizers were discussed and compared. The results showed that the mechanical properties retention rates of light stabilizer 2020, light stabilizer 944, light stabilizer 123, light stabi-lizer 770 and light stabilizer 292 were 87.1%, 81.7% and 79.1%, respectively %Light stabilizer 2020 and light stabilizer 944 with large molecular weight are more easily compatible with the system, not easy to precipitate, and have a better an-ti-aging effect. At the same time, light stabilizer 2020 with dense hindered amine structure has excellent anti-aging effect. This study provides a reference for the selection of light stabilizer and failure analysis of light aging resistance of HDPE system.

Temperature control plays a vital role in the circuit board production process. In order to control the temperature change in the reflow oven, we establish a differential equation model of the PCB heat transfer based on the theory of heat transfer and use the boundary conditions to solve the temperature distribution in the oven. We also accurately simulate the heating and cooling process of the PCB. According to the requirements for the shape of the oven temperature curve in actual production, we respectively use the heating factor and the area enclosed by the temperature as evaluation indicators, establish a target optimization model, and obtain the best set temperature for each temperature zone and the best transmission speed of PCB board. Through analysis of different cases, we could get the conclusion that the model in this paper is reasonable and effective.

Rubber is a super-elastic material. Super-elasticity can be used to analyze rubber-like materials. This material can withstand large strains and large displacements, but has minimal volume change (incompressible), and has two characteristics: material nonlinearity and geometric nonlinearity. In the research process, the positive pressure, shear force and void of the circular rubber bearing were analyzed. For the circular bearing, it can be found through research that the tensile stress of the rubber layer of the rubber bearing increases rapidly with the increase of the vacant area of the bearing, and the slope of the curve is also increasing. The maximum stress of the rubber layer generally appears between the upper first layer of steel plate and the second layer of steel plate. When the void area reaches 30%, the tensile stress of the rubber layer between the first layer of steel plate and the second layer of steel plate reaches 32.8MPa, which is greater than the specified 17MPa, which causes the cracking and deterioration of the inner rubber layer of the bearing, and finally leads to the rubber support. Because of the collapse of the seat, the vacancy of the seat must be paid attention to in the design and construction process.

In previous studies of newly fabricated surface-coating materials, the super hydrophilic surface etched by Cu2+/HNO3 exerts higher drag-reduction effect at low Reynolds numbers than the modified superhydrophobic surface even with similar surface structure. In this paper, both experimental and modelling fluid dynamics studies are used to invest the drag-reduction and flow field for these super hydrophilic surfaces in the microchannel. The experimental results showed that the drag-reduction rate would gradually decrease with the velocity increment of medium. Besides, the dissolved gas does play a key role in reducing the shear stress in the near wall flow field by forming the non-shear air/water interface and increasing its wall-slippage effect. Moreover, the flow-field stimulation analysis provides more intuitive schematic diagram velocity magnitude and pressure changes inside the microchannel, and the surface roughness obtained by chemical etching is capable to enhance the drag-reduction effect as well. Published version This work was supported by the National Natural Science Foundation of China (grant number 51704258); the research foundation of Zhuzhou Smelter Group Co (grant number ZYKJ20190422002); and the Natural science foundation of Hunan Province, China (grant number 2019JJ50587).

The stick-slip Vibration is one of the major causes for drilling quality reduction, shorter drilling tool lifespan, drilling efficiency decrease, it also affect the drilling cost and completion period seriously. The complex situations in the process of drilling result in the slow progress in this aspect, they rarely break through. The recent advances are outlined in stick-slip vibration of the drill string in three areas: theoretical analysis, experiment research and control strategy. The main research direction, methods and existing problem in the progress are introduced, which will provide reference and guidance for further research.

In order to provide reference and help for sand production control in deep tight sandstone gas reservoirs. Taking Keshen block as the research object, the sand production mechanism is analyzed and verified by experiments. The additional pressure difference, fracture development and reservoir reconstruction are considered. Through the establishment of rock mechanics model, hole additional pressure difference physical model experiment, acid rock test. It is concluded that the main sand production mechanism of this formation is shear failure, additional pressure difference of rock, sand production easily caused by natural fracture development, and rock strength decreases after acid fracturing. The rock strength decreases by 20%.

North China is one of the earthquake-prone areas and Zhangjiakou-bohai belt is one of the main seismic tectonic belt in North China. There are many cross-faults in the belt and strong earthquakes occur at the intersection of faults. In order to explore the fault behavior and strong seismic mechanism of cross-fault system, we establish 3D finite element models to simulate the sliding activity of faults under the regional tectonic environment.

This paper is based on engineering background in the phosphate mine called Jianlinshan belonging to the Yunnan Phosphate Chemical Group limited company. In terms of the deformation and instability characteristics of stratified steep dip rock slope, the slope instability process and intrinsic controlling factor have been analyzed by using the cusp catastrophe model. The excavation open-pit slope stability has been researched with respect to the stress state of the stratified rock slope. The results show the following conclusions. (1) The increase of strata thickness can improve the flexural rigidity of rock mass, and can effectively control the occurrence of slope collapse and buckling. The risk of destabilization of the slope can be reduced by using rock-soil anchorage technology or grading bedding. (2) When the slope rock thickness is fixed, the critical slope length decreases with the increase of the dip angle, and the higher the thickness, the more obvious the decreasing trend; When the dip angle of strata is certain, the critical slope length of the slope increases with the increase of the stratum thickness, and the increasing amplitude decreases. Meanwhile, when the dip of strata is greater than 40°, critical slope length increasing amplitude caused by the thicker thickness of strata tends to coincide. The relevant research results can provide theoretical and technical guidance and advice for the open pit transportation technology of this mining area or mining area with similar conditions.

The tensile shear samples of potting epoxy resin materials were accelerated under 90°C, 100°C and 110°C temperature conditions. The tensile shear strength was used as the aging characteristic index during the aging test. After normalizing the data in the descending section, the storage life evaluation and analysis is performed based on the Arrhenius model. The retention rate of tensile shear strength is 50% as the critical failure condition. The storage life at 25°C is predicted to be 21.7 years. During the thermal oxygen aging process, the epoxy bonding material’s adhesive interface first undergoes post-curing reaction under the action of heat, and then undergoes oxidative degradation under the action of thermal oxygen. The sample interface is more susceptible to oxidative degradation than the interior. In the oxidative degradation stage, the part of the epoxy resin connected to the hydroxyl group is oxidized to the aldehyde group, and the methylene group connected to the N in the curing agent is oxidized to C=O, forming C=O in the amide, and the molecular backbone is broken And produce low molecular weight polymers.

Compared to the conventional phase change materials, the new phase change material Ta-Sb2Te3 has the advantages of excellent data retention and good material stability. In this letter, the etching characteristics of Ta-Sb2Te3 were studied by using CF4/Ar. The results showed that when CF4/Ar = 25/25, the etching power was 600 W and the etching pressure was 2.5 Pa, the etching speed was up to 61 nm/min. The etching pattern of Ta-Sb2Te3 film had a smooth side wall and good perpendicularity (close to 90°), smooth surface of the etching (RMS was 0.51nm), and the etching uniformity was fine. Furthermore, the mechanism of this etching process was analyzed by X-ray photoelectron spectroscopy (XPS). The main damage mechanism of ICP etching in CF4/Ar was studied by X-ray diffraction (XRD).

The numerical simulation and fluid dynamics simulation of the internal flow field and its influence mechanism of a commercial vehicle intake system were carried out aim at studying the flow field characteristics of the intake system. The internal and surface pressure, velocity, and turbulent kinetic energy distribution of intake systems under the rated operating conditions and three high torque conditions of the engine were analyzed. The simulation results showed that with the increase of the mass flow of the intake air, the pressure distribution on the surface of the intake system increased, and the pressure drop of the inlet and outlet increased rapidly. With the increase of the mass flow, the scale and number of vortexes in the intake system increased sharply. The distribution of turbulent kinetic energy is more related to the velocity field distribution. However the internal turbulent energy distribution of the intake system is concentrated under one condition. As the intake air mass flow rate drops from 1,500 kg/h to 764 kg/h, the pressure drop of the intake system drops from 2,858,566 Pa to 721,411 Pa; the average turbulent energy decreases from 5.41 m2/s2; to 0.896 m2/s2. In this paper, the research on the flow field of the engine intake system aims to provide research directions for the early stage of the structural design of the intake system of large agricultural vehicles.

For physically understanding the dynamic response of a photovoltaic (PV)-based integrated power system for electromechanical oscillation damping, firstly, this paper develops the linear mathematical model of a single machine infinite bus system integrated with PV in the electromechanical time scale. Then, based on the electric torque analysis method and the functional route of active power control (P-control) and reactive power control (Q-control), the key factors and influence laws of the power system inertial effect, damping level and synchronization capability are analyzed. The results show that when the PV operating mode utilizes the rotor speed as feedback signal, the PID controller parameters of P or Q-control loop can affect the damping level, synchronization capability and inertial effect of the power system, respectively. The accuracy of the physical mechanism analysis is verified by MATLAB.

As an important means to effectively optimize land use, land remediation projects need to be systematically analyzed for their qualitative and quantitative impacts on soil carbon retention. In this study, three types of land remediation project areas, namely sandy land, saline-alkali land, and abandoned residential land in Shaanxi Province, were selected as research objects, and the impact of land remediation years on soil carbon retention capacity was analyzed. The results of this study indicate that due to differences in basic soil properties and engineering implementation technologies, different types of land remediation have different effects on soil carbon retention characteristics. Aeolian sandy land, abandoned homesteads, and saline-alkali land remediation have certain effects on soil carbon retention.

We present a state-to-state dynamical calculation on the reaction S++H2→ SH+ + H based on an accurate X2A″ potential surface. Some reaction properties, such as reaction probability, integral cross sections, product distribution, etc., are found to be those with characteristics of an indirect reaction. The oscillating structures appearing in reaction probability versus collision energy are considered to be the consequence of the deep potential well in the reaction. The comparison of the present total integral cross sections with the previous quasi-classical trajectory results shows that the quantum effect is more important at low collision energies. In addition, the quantum number inversion in the rotational distribution of the product is regarded as the result of the heavy–light–light mass combination, which is not effective for the vibrational excitation. For the collision energies considered, the product differential cross sections of the title reaction are mainly concentrated in the forward and backward regions, which suggests that there is a long-life intermediate complex in the reaction process.

Melamine as single absorbance had been investigated in heavy metal ions removing and it showed good adsorption performance. This paper focused on the chromium (III) remove from wastewater by adsorption with melamine. The results showed that the melamine had a great adsorption surface area of 8.71 m2/g and high adsorption capacity (2843 mg/g) at removal efficiency of chromium (III) (98.63%) within 60 min at n (melamine)/n (chromium)=1.5 and reaction temperature at 90 °C. The adsorption process was described by Langmuir isotherm and the kinetic process was fitted well with pseudo-second-order model. The adsorption process was a spontaneous, endothermic and physisorption process according to the thermodynamic analyzing results. This study provided a good evidence for successful application of melamine in adsorptive removal of chromium (III) from wastewater.

In this study, BPA was selected as the research object to explore the effect of BPA on the development of reproductive system and its damage mechanism in the weaning F1 male offspring SD rats. The development of sexual organs and the change of sex hormone level in F1 male offspring were observed from the day of pregnancy when BPA of 50mg / kg, 100mg / kg and 200mg / kg was administered to the mother rats to the weaning period. The results showed that the serum PRL level of F0 parent rats in BPA group increased significantly at the end of weaning period, and the serum E2 level of 100 mg / kg and 200 mg / kg groups increased significantly. In F1 offspring, the dose of BPA was positively correlated with the level of serum E2, negatively correlated with the level of serum T, FSH decreased in 200mg / kg BPA group, and the organ coefficient of testis decreased significantly in 100mg / kg and 200mg / kg groups compared with the control group.

The CO2 arc welding was carried out under a longitudinal magnetic field, and the arc shape has been studied by using a high-speed camera. From the camera images, we know that under the action of the longitudinal magnetic field, the upper end of the arc will constrict and the lower end of the arc will expand. It would become a bell-type shape and rotate at a high-speed in the optimum range of magnetic field parameters. The arc shape was simulated using a mathematical model, which was established based on experiment data and theoretical knowledge, and mechanism analysis has been carried out regarding the effect of longitudinal magnetic field on CO2 welding arcs.

The process of bullet-barrel interaction refers to the following physical process: after the gun is fired, the bullet moves forward under the push of powder gas, interacts with the barrel by extrusion, friction, contact and collision, and finally leaves the barrel. The swing phenomenon of bullet, which has a great influence on the shooting accuracy, is formed in this process. In order to study the formation of swing phenomenon and effect of barrel structure on swing, a finite element simulation model for the interaction process of a sniper rifle is established and calculated in this paper. The movement and stress distribution of bullet and barrel in bullet-barrel interaction process are obtained by simulation calculation, the swing of the bullet under different bore throat taper and rifle type is compared, and the intuitive process of the swing phenomenon of the bullet is obtained. Based on the calculation results, the following conclusions are obtained: Firstly, the dynamic process of bullet swing formation and amplification is obtained. In pre-shooting stage and extrusion stage, because of eccentricity of structure and other reasons, the bullet’s axis deviates in the process of embedding to form initial disturbance, called formation stage. In post-extrusion stage, the initial disturbance is continuously amplified due to the combined action of bullet structure, contact between bullet and barrel, and the pressure of powder gas, finally, the swing phenomenon of bullet is formed, called the amplification stage. Secondly, the effects of bore throat angle and rifle type on bullet swing are obtained.

Waste copper slag contains large amounts of iron. Carbothermic reduction of the copper slag to recover iron inevitably results in the co-production of copper, which causes brittleness and poses a significant cost to remove. In this work, the method of medium-temperature (MT) chlorination by sodium chloride and high-temperature (HT) reduction by carbon is used to remove copper selectively before the recovery of iron. The composition of raw materials and the products were analyzed by X-ray diffraction (XRD), and chemical analysis. It was found that excessive carbon and high temperature were unfavorable to the removal of copper from the copper slag. Cu2S and Cu can be chlorinated by sodium chloride and evaporates in the form of CuCl gas. Meanwhile, chlorination mechanism of copper slag was discussed.

Electric Field Heat treatment has a significant effect on the superplasticity, recrystallization and phase transformation of metals, and can also improve the superplasticity and mechanical properties of materials. The effect of electric field on high temperature decarburization of high carbon steel was studied by comparing the decarburization degree of high carbon steel under electric field and non-electric field. The mechanism of the electric field is analyzed. The Electric Field promotes the migration of vacancy or vacancy + solute atoms to the grain boundary, dislocation or sample surface to realize the diffusion process.

Examining the driving factors of energy consumption at city scale, is an important measure for effectively achieving energy saving and emission reduction. An extended STIRPAT model based on the classical IPAT identity is adopted to uncover the main drivers for total energy consumption in Suzhou, an important manufacturing city in China, during 2006 to 2016. The main conclusions are as follow: (1) Foreign trade, economic growth, and industrialization are the three dominant contributors to energy consumption increments. Furthermore, quite significant portion of Suzhou’s foreign trade is processing exports. The export products are mainly high-energy consumption such as electromechanical, chemical, textile, etc. The export-oriented economy is accelerating the economic growth and industrialization, and also strengthening the energy intensive regional development mode. (2) Urbanization and population size are also the main driving factors for the rapid growth of energy consumption in Suzhou. The population scale effect exhibits the urban function of absorb employment and agglomerate population in Suzhou, it also demonstrates the growing energy demands caused by population growth and the accompanying urbanization process. (3) Energy consumption intensity and energy consumption structure are the important influencing factor in curbing energy consumption in Suzhou. Energy saving effects played by energy consumption intensity are stronger than energy consumption structure. The coal-based energy consumption structure has not been changed fundamentally during the research period. Therefore, the energy saving effect of energy structure has not been fully utilized. The current and future major strategies for controlling energy consumption in Suzhou should further improve energy utilization efficiency, optimize energy consumption structure, and reduce the proportion of coal consumption.

It is difficult to reclose transmission line successfully after tree fault occurs, which is easy to cause line outage. At present, most of the existing research focuses on the diagnosis and disposal of tree faults, while the mechanism of tree faults is relatively rare. Firstly, the formation process of tree faults and the typical discharge characteristics at different tree height stages are analyzed. Then, the process of tree-wire gap discharge at different stages is simulated in laboratory environment. With trees approaching transmission lines, corona discharge, hidden discharge and flashover discharge occur in turn, and the discharge increases from weak to strong, and the amplitude increases, while the frequency of discharge waveform tends to decrease.

The spring sensible heating (SH) over the Tibetan Plateau (TP) serves as a huge ‘air pump’, significantly influencing the Asian summer monsoon, has experienced a decreasing trend. However, it remains unclear whether this decline will continue. Therefore, we here examine the long-term trends of spring SH over the central and eastern TP (CETP) based on a meteorological station-based calculated SH dataset, and CMIP6 multi-model simulations. These two sources confirmed the previous finding that the SH peaks in May. Further, we find that the declining SH was replaced by a fast recovery after approximate 2000 in the station-based SH. This is to some extent verified by the historical simulations of CMIP6 models. Importantly, CMIP6 future projections suggest that this increasing trend will continue, and get stronger with higher radiative forcing from SSP126 to SSP585. Mechanism analysis indicates that the previous decreasing trend in SH was mainly caused by the decline of 10 m wind speed, while the recent and future increasing trend results from the rising ground-air temperature difference. We suggest that this increasing trend of spring SH over the CETP may serve as an alternative driver for the enhancement of the East Asian summer monsoon in the future.

At present, the rod production system is difficult to meet the requirements of directional wells and cluster wells with large slant, the rod and pipe of these pumping wells suffer from serious wear, high energy consumption and low system efficiency. Downhole drive reciprocating pump production system, cancelling the sucker rob for transferring forces and motion, utilizing downhole submersible motor drives the reciprocating pump through the downhole drive mechanism, which can avoid the wear of the rod and pipe and improve the system’s efficiency. The composition and working principle of downhole drive reciprocating pump production system are introduced. The scheme of downhole drive reciprocating pump production system based on rack and pinion drive is analyzed in detail. The dynamic model of rack and pinion is established. By the dynamic simulation of the downhole transmission mechanism, the vibration loads of the mechanism with start up different accelerations are analyzed, and it is concluded that it is better to start with the variable acceleration. The scheme can reduce the vibration load caused by the motion inertia to the mechanism and improve the service life of the whole oil production system.

The change of water content of expansive soil in canal slope is very unfavorable to the stability of the slope. In order to analyze the influencing factors and laws of water cut, the relationship between water content and voltage of expansive soil, the relationship between initial water content and expansion force, initial water content and disintegration of expansive soil were tested relationship. The gray correlation model was analyzed based on the vertical displacement, water content, suction, rainfall, soil temperature and temperature data collected on the site. It is preliminarily believed that the main influencing factors of the change of water content of expansive soil in the test section are temperature, rainfall, evaporation and suction. The mechanism analysis of the grey relational model is also obtained: due to the lag of the rainfall infiltration process, the atmospheric rainfall can only penetrate into the 1.6m deep strong expansive soil after 3d, and the influence depth is less than 6.1m. The research on the influencing factors of the change of water content of expansive soil provides the basis for the development of prevention and control measures for canal slope soil in the middle route of South-to-North Moisture Diversion Project and the safe management of channel operation.

The structure of Fiber-Optical Current Transformer (FOCT) is completely different from that of traditional electromagnetic transformer, and the error analysis method is quite different from that of traditional transformer. However, there is no systematic calculation method for the error of FOCT at present. Starting from the working principle and structure of fiber-optical current transformer, this paper theoretically analyses and deduces all kinds of error sources of FOCT, puts forward the error calculation method of FOCT, calculates the overall error based on the actual parameters of a 200 kV Fiber-Optical Current Transformer, and proposes a method to compensate the measurement error of FOCT by changing the initial phase angle of λ/4 wave plate. The initial phase angle of the λ/4 wave plate with the best error compensation effect is 86 degrees.

Solar energy is the most abundant source of renewable energy upon which most conversions of energies could be possible. Solar tracking can be one method through which the energy reception could be increased. Heliotropism is a phenomenon that is observed in various botanical species like leaves, flowers, stems, etc, where there is reaction observed by various parts of the plant corresponding to a solar stimulus. The classic example of this phenomenon is the sunflower effect wherein the sunflower tends to orient itself towards the sun all throughout the day and receives maximum energy at its surface. Similarly, such an effect can be produced using the conventional four bar mechanism which would toggle around the spectrum of the sunlight received to at various positions at various durations of the day. This format of receiving energy would not only increase the quanta of packets being received on an average throughout the day but would also not waste the energy falling on the earth’s surface due to the misalignment of Photovoltaic (PV) cells usually installed in just one direction.

This paper described the environmental problems caused by the furniture industry transfer. Through the mechanism analysis on the cause of environmental problems, it put forward the countermeasures to improve.

Hydrogen bubbling is a typical corrosion morphology caused by hydrogen sulfide corrosion. In order to explore hydrogen sulfide corrosion of iron, the composition of flue gas under actual conditions was simulated in this research. Hydrogen sulfide corrosion in flue gas of four kinds of materials selection of ground process pipeline and underground pipe string was researched experimentally. The pressure and temperature of hydrogen bubbling corrosion morphology under actual flus gas conditions were obtained. The electrochemical corrosion mechanism between iron and hydrogen sulfide was investigated.

The earthquake event with M 6.7, on 7th December 2106 in Pidie Jaya, inflicted heavy casualties and material losses. In 1967, an earthquake event occurred near Pidie Jaya with M 6.1 which caused by Samalanga fault. However, the Pidie Jaya earthquake, although very close, but was not caused by the Samalanga fault activity. The latest, an unkown fault was considered as an active fault and the location of earthquake sources and and a part of the branching of Samalanga fault. It is very interesting to discuss, generally earthquake in Aceh, always happen on Sumatera fault’s path. Analysis of earthquake source mechanism is very important to do, to know the fault characteristic and direction. The analysis in this study involves inversion of tensor moments with isola program on each recording component, which will provide a synthetic wave as a comparison. The earthquake mechanism which obtained from the inversion is strike-slip with left-lateral and has the parameter strike 254°, dip 80°, and rake 48° on the first nodal plane as the true nodal. While, the second nodal has the plane parameter is strike 153°, dip 42°, and rake 165°. From these parameters, the first nodal plane that has a strike 153° is considered to be interpreting the new fault line as it is also followed by the direction of the spread of aftershocks. These result indicate that the Samalanga Fault is not the cause the Pidie Jaya earthquake, and shows the real direction of Pidie Jaya fault from South-West to North-East with lef-lateral orientation.

The successful of intensive aquaculture is strongly influenced by the ability of the farmers to overcome the deterioration of water quality. The problem is low dissolved oxygen through aeration process. The aerator device which widely used in pond farming is paddle wheel aerator because it is the best aerator in aeration mechanism and usable driven power. However, this aerator still has a low performance of aeration, so that the cost of aerator operational for aquaculture is still high. Up to now, the effort to improve the performance of aeration was done by two-dimensional blade design. Obviously, it does not provide an optimum result due to the power requirements for aeration is directly proportional to the increase of aeration rate. The development of movable blade is based on fact that power is required only when blade of paddle wheel aerator entering water and in contrary action of aeration effect only when the blade is about leaving the water. This study was carrier out to design paddle wheel aerator with movable blade which will open when entering water and close when leaving water. Wheel closed at quadrant I to IV (entering water surface) and was about to open at quadrant III to II (leaving water surface). The blade was designed referring to commonly used Taiwan wheel model. The size of the blade was 15 cm of width, 20 cm of length, trapezoid-shape with 15˚ of bottom side and 30˚ of top side, had 40 holes with diameter of 1.6 cm. The component of mobable blade mechanism consisted of cam and shaft, rim, rim cap, blade holder, follower, spring and bearing. Follower was able rotate with angle of rotation was 1250, rotational displacement was 50 mm, maximum velocity was 0.55 m/s and acceleration was 6.09 m/s2. The largest angle of pressure occurred between cam and follower was 40.120 and the maximum torque required to rotate movable wheel was 80.09 Nm. The result shows that the testing without a load at 115 rpm, the torque that occured is 43.05 N·m and the electric power consumption is 511.72 Watt. However, the electrical consumption is still higher comparing with Taiwan paddlewheel aerator model due to the friction occured on the follower and cam.

Hyogo Framework for Action (HFA) on disaster risk reduction (DRR) has not been fully implemented, but now there is a rise of awareness and need to integrate a new DRR Framework with the Sustainable Development Goals (SDGs). Facing this perspective, Indonesian stakeholders also aware about the importance of integrating DRR with SDGs, but they need to consider related aspects such as mechanism analysis and readiness of stakeholders. This analytical descriptive study aimed to analyse the causative factors of disasters and any response needed, as well as portrays the readiness of regional disaster managers in fulfilling the global DRR agenda. The study was conducted in some particular provinces and districts with the incidence of volcano eruption (North Sumatera Province), mining-related disaster (Bombana District, South-East Sulawesi Province), and floods (Bandung District, West Java. Primary data were collected through interviews and focus group discussions. Results of the study found several important findings, which were disaster management had not become one of the priorities of district's development program, DRR has not been integrated both in development and in implementation of regular development program. After the focus group discussion, stakeholders has become more convinced that disaster disturbs the development program, therefore several disaster managers began to consider the importance of DRR, evaluate the impact of disaster on development, and integrate DRR with SDGs. There had been no comprehensive calculation of the impact of disaster on SDGs achievement because of several constraint, which must be faced in the implementation of the integration of DRR with SDGs. The findings highlight the importance of advocacy efforts for disaster management and capacity building for stakeholders in the future.

Granite is widely distributed in coastal areas of China, but granite, as an acid stone, can not be used directly in asphalt mixture. Combined with the climatic conditions in coastal areas, we can prepare materials for local projects, save engineering costs, and prepare composite modified asphalt. The 5% nano-calcium carbonate and the 5% rock asphalt are added to prepare modified asphalt. The results indicate that the adhesion level between granite and asphalt is increased to 4th grade. The dynamic stability is increased to 3652 times/mm. The residual stability is increased to 91%. The high temperature and water stability of the modified asphalt mixture are increased, and the modification mechanism is researched with the chemical composition of the modifier.

Uniform graphene films and micro-patterns are the cornerstones of graphene-based printed electronics. However, disk-like reduced graphene oxide (RGO) sheets trend to concentrate at the edge of the drop because of the famous coffee-ring effect, resulting in non-uniform patterns. To understand the physics of coffee-ring formation for RGO droplets on hydrophilic substrates, we propose a mechanical model to elucidate the influence and its mechanism of substrate wettability on the solute migration behavior and solute distribution morphology of RGO droplets. Stronger coffee-ring morphology and a slower velocity transition on the PMMA can be observed as compared to that on the glass slides. An explanation based on the mechanical model is provided as the large contact angle on the PMMA leads to a small hindrance force and finally results in more significant coffee-ring morphology. Remarkably, we have revealed one underlying mechanism by which the hydrophilic substrate with better wettability will form more uniform patterns. This study can provide fundamental insights into the relationship between substrate wettability and RGO sheets distribution morphology. It might contribute to morphology regulation of RGO droplets in the DOD printing of graphene films and micro-patterns.

Commercially pure aluminum is a widely used conductive material in the field of overhead transmission. Yield strength, which is closely related to the reliability of conductive material in service, is an important parameter of mechanical property. Aluminum wire, which is widely used as the outer layer of steel core aluminum strand, is usually prepared by cold-drawing process. With the increase of area reduction, the strength of aluminum wire increases continuously and thus yield strength prediction becomes a very important scientific issue based on the strengthening mechanism analysis. In this paper, the contributions of grain refinement and hard texture to the yield strength were calculated by characterizing the microstructure of aluminum wire with different area reductions. Subsequently, the yield strength prediction model was set up by means of the quantitative calculation and function fitting of grain refinement strengthening and texture strengthening. By using this model, the yield strength of aluminum wire can be well predicted based on the average grain size of initial aluminum rod and this model can also guide the design and production of aluminum wire in industry field.