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The production process in the gas reservoir with an aquifer is complex. With gas production, aquifer water could possibly flow into the production well and accumulate within the well bore, which leads to a lower production rate and may even block the producer. However, few studies in the literature investigate the damage caused by the liquid phase in this kind of reservoir or predict gas productivity using the relationship between reservoir pressure and water gas ratio (WGR). For this reason, it is important to know the effects of the formation of liquid phase behavior on production when an aquifer is present under a gas reservoir. From the results of published literature reviews, we found that studies focused on the production of a gas reservoir with bottom water. Nevertheless, for gas well damage from the liquid phase behavior, we found that there was no statistical data or mathematical model of the relationship between reservoir pressure and the gas oil ratio (GOR), which affects production. In this research, based on the theory of fluid flow in porous media, a new mathematical model of water and gas production and a new equation on gas well productivity is developed. To verify the model and equation, gas production data collected from the field are applied. By analyzing the typical gas reservoir with bottom water and the collected data, influences from the liquid phase behavior are shown. In this way, mathematical relationships between reservoir pressure and the WGR and between the GOR and production decline were obtained. The new gas productivity model is derived from the gas and water pseudo pressure functions, which can be applied to analyze well damage caused by the liquid phase. In order to verify the mathematical model, production data were collected from a typical gas reservoir with an aquifer located in the Changxing gas reservoir. The results indicate that a semi-logarithmic linear relationship is obtained between the WGR and productivity decrease. When the WGR increases from 0.5 to 15 m 3 /10 4 m 3 , damage caused by liquid phase decreases to 59%. The tendency of gas productivity in the Changxing gas reservoir was obtained so that it decreases as reservoir pressure decreases and increases as the WGR decreases. The gradient of the gas productivity deduction increases as the WGR increases. By the end of the data analysis, two linear equations indicating the relationship between gas productivity and reservoir pressure and the relationship between gas productivity and the water gas ratio are obtained: Q A O F = − A 1 l n W G R − B 1 and Q A O F = A 2 l n P − B 2 , respectively. The new model and these two equations can be applied to predict gas productivity in the gas reservoir with an aquifer and determine the damage level to the gas well. They also can be used to guide development plans in the gas reservoir with an aquifer.

Complex fracture systems including natural fractures and hydraulic fractures exist in shale gas reservoir with fractured horizontal well development. The flow of shale gas is a multi-scale flow process from microscopic nanometer pores to macroscopic large fractures. Due to the complexity of seepage mechanism and fracture parameters, it is difficult to realize fine numerical simulation for fractured horizontal wells in shale gas reservoirs. Mechanisms of adsorption–desorption on the surface of shale pores, slippage and Knudsen diffusion in the nanometer pores, Darcy and non-Darcy seepage in the matrix block and fractures are considered comprehensively in this paper. Through fine description of the complex fracture systems after horizontal well fracturing in shale gas reservoir, the problems of conventional corner point grids which are inflexible, directional, difficult to geometrically discretize arbitrarily oriented fractures are overcome. Discrete fracture network model based on unstructured perpendicular bisection grids is built in the numerical simulation. The results indicate that the discrete fracture network model can accurately describe fracture parameters including length, azimuth and density, and that the influences of fracture parameters on development effect of fractured horizontal well can be finely simulated. Cumulative production rate of shale gas is positively related to fracture half-length, fracture segments and fracture conductivity. When total fracture length is constant, fracturing effect is better if single fracture half-length or penetration ratio is relatively large and fracturing segments are moderate. Research results provide theoretical support for optimal design of fractured horizontal well in shale gas reservoir.

HIAF (High Intensity heavy ion Accelerator Facility) is a project proposed by IMP (Institute of Modern Physics, Chinese Academy of Sciences). This paper designs a digital controller for Bring in HIAF dipole power supplies system, which is several circuit boards consist of high precision ADC, optical fiber module, DDR3 SDRAM, Gigabit Ethernet module. It uses Cyclone V SX SoC FPGA, which integrated with dual-core ARM Cortex-A9 MP Core processor. This paper explains the hardware and software architecture of the controller and how can it improve power supplies performances. The FPGA finishes the PI regulating and PWM modulation. The ARM is responsible for data pre-setting, web service, database, and power supplies detection and protection management. At the end, this paper gives the output measurements when the controller is used in the prototype, which verifies the rationality and reliability of the design., Proceedings of the 14th Int. Conf. on Heavy Ion Accelerator Technology, HIAT2018, Lanzhou, China

In high-temperature, high-pressure (HTHP), water-soluble gas reservoirs, a significant amount of natural gas is dissolved in the formation water. During development, with changing reservoir pressure, the natural gas in the formation water will be released. The released natural gas will carry the formation water to form gas-liquid two-phase flow into the porous media of the gas reservoir, which results in premature water breakthrough, thus changing the law of formation water invasion. In order to determine the influence of water-soluble gas on formation water invasion, it is important to study the water-soluble gas content of water-soluble gas reservoirs. Based on experimentation and existing modeling, a prediction model was established for water-soluble gas content in HTHP water-soluble gas reservoirs, and the influence of water-soluble gas content on water invasion was studied. From the results, the following conclusions can be drawn. (a) The content of water-soluble gas increases with increasing pressure, first decreasing and then increasing with increasing temperature. (b) In addition to temperature and pressure, the factors affecting the content of water-soluble gas include the gas components and the mineralization degree of formation water. (c) The existing prediction model has the problems of large error and inconsistency with the measured value, (average error being 33.92%), especially lacking consideration of how changing carbon dioxide content in the gas composition affects the water-soluble gas content. (d) Considering the influences of temperature, pressure, gas components, and formation water mineralization on the prediction model of water-soluble gas reservoirs, the calculation results of the model are more in line with the actual circumstances of gas reservoirs, with the average error being 6.81% and the accuracy of water-soluble gas content prediction being increased five times. (e) Through case analysis, it is shown that the release of water-soluble gas has a great impact on the water breakthrough law of gas wells. Considering the water-soluble gas, the water breakthrough time of gas wells is relatively early. Results show that the water-soluble gas content prediction model for HTHP water-soluble gas reservoirs can predict the water-soluble gas content of water-soluble gas reservoirs more accurately, laying a foundation for understanding the water invasion law of water-soluble gas reservoir development and developing such a gas reservoir efficiently.

Bcl2-associated athanogene 3 (BAG3) belongs to the BAG family and regulates many biologic behaviors of tumors. When tumor cells are in a hypoxic condition, BAG3 protein expression level increases, as does HIF-1α which is an important transcription factor induced by hypoxia. Glioblastoma is one of the typical solid tumors existing in a hypoxic microenvironment that can activate expression of BAG3 and HIF-1α. This research aimed to reveal the relationship between BAG3 and HIF-1α and their effects in glioblastoma multiforme. We found that down-regulated BAG3 inhibited proliferation and promoted apoptosis of glioblastoma multiforme U87 and U251 cell lines by decreasing HIF-1α expression level. The mechanism of BAG3 regulating HIF-1α is mainly through increasing degradation of HIF-1α by HSP70. When HIF-1α was up-regulated, induced by HIF-1α plasmid transfection on the basis of down-regulation of BAG3, the proliferation inhibition and apoptosis promotion were partially reversed. This novel result showed, for the first time, that down-regulation of BAG3 resulted in a low expression of HIF-1α under both normoxic or hypoxic conditions and finally caused inhibited proliferation and promoted apoptosis in glioblastoma. The mechanism of down-regulated BAG3 decreased HIF-1α protein expression through enhancing formation of HSP70-HIF-1α complex and promoting degradation of HIF-1α by HSP70.

It is important that the tight gas reservoir is developed with test wells in the first place for the reasonable development, and it is necessary evaluation production index of test well. So, the paper will evaluate gas wells capacity, reasonable production, production decline law and producing reserves. Combining with calculation theory, comparison of adjacent wells and field practice, obtained reasonable production, production decline law and production reserves about test well, and through analysis the adjacent well obtained development experience and lessons about tight gas reservoir. The results show that the gas well development should pay attention to reasonable production and prevent energy falling too fast in tight gas reservoirs, The decline rule of wells with long production time should be analyzed by two stages. Through study, it will provide some reference and guidance for the development of gas wells in tight gas reservoirs.

A snake well is a complex well type and meanders in a sinusoidal pattern through multiple drainage areas provided by multiple isolated production zones. Conventional productivity calculation methods for horizontal wells could not be applied directly for snake wells because the production segments in the wellbore have large vertical fluctuation and wellbore pressure drop is noticeable. Starting from the distribution of velocity potential produced in an infinite reservoir by one snake well, this paper uses mirror image and the principle of superposition to obtain velocity potential and pressure distributions in bottom water drive reservoirs with and without gas cap, and edge water drive reservoir. Flow characteristics along the wellbore are then investigated and a pressure drop model is developed. Coupling the flow inside wellbore and in the reservoir, we developed and further solved a productivity prediction model for the snake well. The proposed approach to calculating well productivity better meets the reality and results in more accurate prediction. Case studies in bottom water drive reservoir with and without gas cap, and edge water drive reservoir show that snake wells with small fluctuation rates yield higher productivities than horizontal well. Also, permeability anisotropy has less impact on the productivity of snake well than that of horizontal well. For the reservoir with low vertical permeability, snake well can perform better than horizontal well.

The function of capillary pressure in the process of CO displacement in low-permeability reservoir is researched through combination of indoor experiments and numerical simulation. On the basis of different displacement experiments in long core chamber, one-dimensional numerical simulation component model is built to research the function of capillary pressure under the different CO displacement ways. The results show that the capillary pressure under the different CO displacement ways is not consistent. Capillary pressure is the driving force in the process of CO displacement while resistance force in the process of CO pressure buildup and displacement. In order to promote reasonable and efficient development of low-permeability reservoirs, it is suggested that further study about microscopic effects and laws of the capillary pressure in the reservoir should be done through experiment.

Die service life improvement is an important problem in high-pressure die casting industry. Former studies show that biomimetic laser remelting process provides desirable microstructural and microhardness changes, which induces the intensified particles for improving the service life. The present study concerns laser surface remelting of H13 tool steel in a quenched and tempered state using an Nd:YAG laser. This purpose is to obtain data for establishing database of laser parameters for H13 material, which is helpful for applying laser remelting on die casting dies. The influence of laser parameters on the characteristics of the unit has been investigated. The interrelationships among the laser processing parameters, the penetration depth, the width, and the area of the unit were discussed by single-factor experiments. A set of die casting die was selected and processed by laser remelting, and the die service life has been increased from 13,000 shots to 27,000 shots under practical die casting conditions.

Die service life improvement is an important problem in high-pressure die-casting industry. Die service life, which is defined as the maximum product number produced before it fails, and die performance directly determine the production cost and quality of die-casting product. To reduce the repair and maintenance costs, an approach to prevent die from thermal damage and prolong the die lifetime is required. Biomimetic laser-remelting process (BLRP) provides a promising method to improve the service life of die-casting mold. However, the laser processing regions can only be determined by experiences. In order to determine the exact laser processing regions for a set of new die before BLRP, a combination system of CAE and BLRP is proposed in this paper. Through analyzing the mold filling process and the temperature distribution, potential thermal cracks are worked out by numerical simulation system, which are the laser processing regions. The method proposed in this paper advances the efficiency of the BLRP. And practical production validates the veracity and the reliability of the method.

Die service life improvement is an important problem in high-pressure die-casting industry. As many factors affecting the service life, die service life improvement is a systematic project. In this paper, a cover die-casting die was investigated in order to increase its life time. Different die materials, computer-aided engineering (CAE) analysis, biomimetic laser-remelting process, and die structure optimization are adopted in order to enhance its performance. The die service lives are traced for dies of different die materials (H13 and SKD61). The die service lives are compared for dies with/without structure optimization with the help of CAE simulation. The application shows that CAE simulation is a useful tool for die structure optimization. Experiment result on SKD61 die steel after laser-remelting process shows that biomimetic laser-remelting process provides desirable microstructural and microhardness changes in biomimetic units, which induces the intensified particles for improving the service life.

Die service life improvement is an important problem in high-pressure die-casting industry. Experiment results on die steel shows that biomimetic laser-remelting process provides a promising method to improve the service life of die-casting die. A casting with uneven wall thickness was selected and problems existing in die-casting production were analyzed. The corresponding die-casting die was processed by biomimetic laser-remelting process. The application result indicates that the service life of the die processed by biomimetic laser-remelting process has been increased from 12,000 to 28,000 shots, which is more than twice that of no processed one under real high-pressure die-casting conditions. The application of laser-remelting process provides desirable micro-structural changes in biomimetic units, which induces the intensified particles effect for improving the service life.

Punches and dies are the real operating components and account for a large portion in the progressive die design procedure. This paper presents a structural design tool for punches and dies for progressive dies of motor core based on functional component. The descriptive model of punch and die component is established which contains three aspect of information, geometry information, assembly-related constraint attribute and hole-related information on plates. Based on the classification and 3D modeling method of punches and dies, the library of components for punches and dies is set up according to the descriptive model. Methods for modeling and data management for components of punches and dies are discussed in detail. The proposed tool for progressive die for motor cores can complete the design of five classes of punches and dies and generate holes on plates automatically. This design tool is constructed on a PC and integrated with a SolidWorks CAD system. The progressive die design for the motor core of house appliance is employed as a practical example to demonstrate the effectiveness of the design tool. The results reveal that it can dramatically improve the design quality and can save both time and costs.