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The Nanmushu carbonate-hosted Zn-Pb deposit is located in the Mayuan district of Shaanxi Province, a newly discovered metallogenic district next to the Sichuan Basin, in the northern margin of the Yangtze Block, which is the largest and the only one that is currently mined in this district. The δ34S values of sulfides are characterized by positive values with a peak around +18‰, and the reduced sulfur may have derived from reduction of SO42- from paleoseawater or evaporitic sulfates that have possibly been leached by basinal brines during mineralization stage. Detailed fluid inclusion study shows two types of fluids in the sphalerite, quartz, dolomite, calcite and barite, that is, aqueous-salt dominant inclusions (type I) and hydrocarbon-bearing inclusions (type II). The Laser Raman spectroscopy study shows occurrence of certain amount of CH4, C4H6, and bitumen. The salinities show similar values around 6 to 12 wt% NaCl equivalent but a decreasing temperature from early to late stages (typically 200° to 320°C in stage I, 180° to 260°C in stage II, and 140° to 180°C in stage III). These features may be related to basinal brines mixing between an external higher salinity CaCl2 ± MgCl2-rich fluid and a local H2O-NaCl methane-rich fluid.

Rubber hose is normally adopted in the connection between the lifting cylinders and the control valves. Low bulk modulus of hose reduces the natural frequency of hydraulic system and brings difficulties to the controller design. This paper focuses on the model simplification of hoses in the hydraulic system. First, a hydraulic lifting system is presented in the paper. Then, simulation model of the lifting system is built in AMESim, and the simplified model of hose is conducted using an improved lumped parameter method. Finally, comparative simulations with the proposed model and the original model provided in the software are carried out. Results show that the simplified model can be used to replace the original model in the simulation of hydraulic systems.

Driving processes and characteristics are different between the water hydraulic artificial muscle and pneumatic artificial muscle due to the difference of work media employed in muscles. An appropriative hydraulic circuit was designed to control the pressure of the water hydraulic artificial muscle and the performance of this system was analyzed. An AMESim model of the control system was built and the dynamic characteristics are analyzed with various parameters of the hydraulic circuit and various loads by simulation. The results show that the performance of the water hydraulic control valve should agree with the dimension of the water hydraulic artificial muscle. The rated flow rate of the water hydraulic valves can be selected increasingly while the load mass is low. Meanwhile, the overshoot is generated and enlarged along with the increases of the flow rate and load mass. These contribute to the improvements of designs and researches on control systems of water hydraulic artificial muscles.

A mathematic method of ensuring motor-based photoelectric tracking instrumentation work high accurately was introduced, the SCA100T inclinometer was settled under the base, and examine plane of base real-timely. The inclinometer output analog signals and transmit it to AT89C51 through A/D converters, and AT89C51 output digital signals and transmit it to PC through RS-232. The PC convert signals of inclinometer into angle values of horizontal axis and vertical axis and transmit the values to main controlled system of photoelectric tracking instrumentation, the controlled system change the angles of horizontal axis and vertical axis. The CAD model was built and simulated with virtual prototype technology .Analysis and simulation proved that the mathematic method could keep tracking precision of motor-based photoelectric tracking instrumentation.

Ultra-high pressure water jet ship rust is one development direction of ship rust removal technique. In order to ensure the normal working of the system, how to control each equipment is the key-part of the design. This study presents the analytical research on hardware technology of the control system of ultra-high pressure water jet ship rust system, the analysis of the principle of frequency control system and circuit design and control circuit of PLC, by analysis the structure and principles of ultra-high pressure water jet rust, and then demonstrates through experimental test that the hardware electronic circuit works properly.

Ship rust removal is an import part of ship-repair and shipbuilding process. Using high pressure water jet equipment causes no environmental pollution. The control and detection of high pressure water jet equipment is the key technology to ensure the system works properly. This study, in light of research on software programming of control system of ultra high pressure water jet ship rust removal equipment, establishes a control system based on PLC through the analysis of the structure and principles of the ultra-high pressure water jet equipment. On the basis of designing hardware circuit of PLC control system, this study mostly analyses software program, and experimental test suggests that the software programming can meet the requirements of system security.

Ultra high pressure abrasive water jet cutting is a new technology device in salvage, ocean development, military fields, and it also is one of the hottest and most advanced topics in the field of fluid control. The present study is aiming at designing a deep sea abrasive water jet cutting system and executive instrument for core technology of large-tonnage salvage equipment. The analysis on the kinematics of cutting trail about executive instrument of abrasive water jet, and the control of actuator movement through the reverse kinematics solution are of certain significance on the establishment of a technological base of application on ultra high pressure abrasive jet and the improvement of the ocean high-tech equipment level.

Due to the problems about Lubrication and sealing in water hydraulics, the poor performance, large leakage, extreme requirements of processing, high cost and poor anti-pollution properties exist in water hydraulic servo or proportional valves of spool structure and analogue control. A better seal is provided by the structure of the poppet valve comparing to the spool valve, however, poorer linearity and control accuracy accompanying inevitably. Aiming at improving the control performance of poppet valve, the design of the multi-digit numerical control valve is analyzed in this paper. The novel design using ball seat valves for digital bits is proposed to ensure enough seal ability and lower the cost. The simulation model of the multi-digit numerical control valve is built in AMESim software and the results show high linearity in flow control. However, large overshoot and oscillation encounter during the switching of the digits. Especially the switching process of the high digital bits requires to be regulated to reduce the large overshooting. The adjustment of the spring in the sensitive chamber of the bit valve can decrease the overshoot and improve the stability. These above contribute to the improvement of the control performance of water hydraulic control valves and applications of water hydraulics in the industry.

Lubrication and sealing are the key research points in water hydraulic technology. A better seal is provided by the structure form of the poppet valve comparing to the spool valve, however, poorer linearity and control accuracy accompanies inevitably. Aiming at improving the control performance of poppet valves, the design of the water hydraulic digital valve is analyzed in this paper. A high speed digital valve is designed and controlled by PWM (Pulse-Width Modulation) and actuated by a piezoelectric ceramic stack with high frequency response and control stiffness. Another new design using poppet valves for digital bits is proposed to ensure enough seal ability and lower the cost of the valve, namely the multi-digit on-off valve. The simulation models of these two types of valves are built and the results show the different performances between the valves. The high speed digital valve is provided with high control accuracy and responsiveness. In contrast, large overshoot and oscillation are encountered during switching on the digits of the multi-digit on-off valve. Especially the switching process of the high digital bits requires to be regulated to reduce the large overshoot. The above analysis contributes to the improvement of lubrication and sealing in water hydraulic control valves and applications of water hydraulics in the industry.