This paper reminisces the association with academicians Shi Changxu, recalls the incidents that Shi Changxu accepted the request for manuscripts and the interview with publishing of foreword or interview paper by "Science & Technology Review". It also describes briefly the speech at the launch of the book"Technology Roadmaps of Chinese Mechanical Engineering", in which, one can learn Shi Changxu's insights deeply in the fundamental research and the development of mechanical engineering technology in China.

For the high speed data acquisition in photomechanical tests with blast loading, a digital laser high-speed photography system consisting of a pumped laser and the Fastcam- SA5 digital high- speed camera is built and applied to the caustics, the photoelasticity, and the schlieren experiments, combining with a blast loading setup. It is shown that the images of the caustics at the running crack tip, the arithmetic line stripes on the surface of photoelastic model specimens, and the propagation process of the blasting wave in the air from charging with slots are recorded clearly, indicating that the new digital laser high-speed photography system is reliable. Also the concept of "one system, various experiments" is realized, which provides some new testing methods and new application fields in blasting mechanics.

In the present work, the effects of quenching transfer time on the mechanical properties and microstructure of A357 aluminum alloys are investigated by using optical microscopy (OM), scanning electron microscope (SEM), differential scanning calorimetry (DSC), transmission electron microscopy (TEM), as well as tensile mechanical properties testing methods. The results show that with the increase of quenching transfer time from 3 s to 49 s, the tensile strength, yield strength and elongation of A357 aluminum alloys are reduced from 351 MPa, 275 MPa, and 12.4% to 320 MPa, 254 MPa, and 6.5% , respectively after T6 heat treatment, together with a continuous declining of tensile strength, tiny variation of yield strength and a continuous variation of elongation. The average length and width size of silicon particles are 10~25 μm and 5~10 μm, respectively, and the morphologies of neonatal and eutectic silicon particles evolve from needle and lamellar structures to spheroidal and rod structures after the T6 heat treatment process. Silicon particles are shown as needle and lamellar mostly when the quenching transfer time exceeds 35 s. The tensile fracture morphology is observed as dimple and intergranular fracture, and the intergranular fracture is increased with the prolonged quenching transfer time. Magnesium and silicon elements are distributed nearby the grain boundaries and the binary and ternary eutectic structures, whereas the aluminium elements are concentrated in the grain and grain boundaries. The length and width size of Mg₂Si phase are 0.2~1 μm and 0.02~0.08 μm, respectively, the precipitation amount and size ratio of Mg₂Si phase are declined, together with the decreases of strength and ductility of A357 aluminum alloy with the prolonged quenching transfer time.

The industry urgently needs economic exploring methods to check and find the underground cave, with physicalmechanical properties different from the around medium. One of the exploring methods is the use of the Rayleigh surface wave. The Rayleigh surface wave theory and the dispersion characteristics in transmission are discussed in this paper, and the Rayleigh surface wave field characteristics are simulated by the finite element method. Shaking with different main frequency epicenters, some models are established with dissimilar depth and size, and tallied up the results of the kinetics and the dynamics characteristics of the Rayleigh surface wave. Using the experiment result of the Rayleigh surface wave exploring methods in Lafayette University's gymnasium from southeast to northwest, for instance, this methods in checking and finding the underground cave are discussed.

Since there is a certain degree of difficulty to carry out a large number of large-scale blasting experiment studies, this paper uses an explosive fluid dynamics numerical analysis method to simulate the explosion cavity formation and the effect of soil compaction around the explosion cavity. First the explosion wave velocity collected from blasting test are analyzed to derive the relevant parameters of the soil, and then with the ANSYS/LS-DYNA ALE algorithm for multiple materials, the problem about blasting the cavity of the soil is analyzed. The relation between the explosion chamber and the degree of compaction of soil before blasting, and how the soil density around the explosion chamber changes with the blasting distance are obtained. There is a good agreement between the blasting results of numerical simulation and field blasting test results.

Comparative study is carried out on the dry weight, the growth(OD₅₆₀)and the arsenic content of the spirulina powder at different arsenic concentrations for the Spirulina platensis from the alkaline lake of Erdos plateau and the introduced species to find out the characteristics of the arsenic enrichment and analyze the arsenic adaptation and the arsenic resistivity of two spieces of Spirulina platensis. The results show that the growth of two spieces of Spirulina platensis is not inhibited, the production of Spirulina platensis from Erdos is higher than the introduced, and the arsenic content of spirulina powder is obviously lower than the introduced at different arsenic concentrations.

This paper aims to solve the problems of the existence of secondary fermentation medium low yield, the poor product identity, the low level of automation, the high energy consumption and many other urgent problems, as well as the complexity of the secondary fermentation medium temperature control inside the tunnel by proposing a computer control system based on PLC, with the computer data acquisition and the real-time control of fermentation process. Fuzzy PID control algorithm is adopted in the system, the fuzzy controller and PID adjustor are realized by PLC, which not only has the agile, reliable peculiarity and the ability of antijamming of a PLC control system, but also improves considerably the intelligence level and the control precision of the control system. The practice results show that the system can effectively control the secondary fermentation medium temperature inside the tunnel, greatly improve the level of automation, and the quality of the products, reduce the labor intensity and the human losses and costs, reduce the energy consumption, with good economic and social benefits.

The oil and gas exploration of Erlian Basin began in 1955, and now more than 10 oilfields have been found, such as Zhabu oilfield, Jigesen oilfield. But, difficulties exist in the exploration of Erlian Basin, due to, for example, the complex of deposit geology and the low level of proven deposits. The previous studies show that there are 50 sags with an independent sedimentary unit of their own, and with their own similar characteristics of hydrocarbon generation, migration and accumulation. But as a matter of fact, even in different subsags of the same sag, the distribution of hydrocarbon source rock and geochemistry characteristics of hydrocarbon source rock are different. This paper analyzes the data of more than 20 sags in Erlian Basin and the Lower Cretaceous hydrocarbon source rocks of more than 30 wells. And then, some common features of distribution and the geochemical characteristics of hydrocarbon source rocks are revealed, and their differences and the effects on the distribution of oil and gas are compared. It is shown that the geochemical characteristics of Lower Cretaceous source rocks have a great influence on the production and distribution of oil and gas in Erlian Basin. Therefore, for the sags with thick dark mudstone, the abundance of organic matter is basically above the medium, the organic matter type is more partial sapropel (type I or II₁), and the dark mudstone is buried deeper than its oil generation threshold depth, and is more conducive to oil and gas output. The contribution of the source rocks of Aershan group to the reservoir is bigger than that of Tenggeer group, so the source rocks of Aershan group have a bigger influence on the distribution of oil and gas.

The lower section of the 4th member of the Shahejie formation and Kongdian formation (Es₄^x-Ek) in the deeper Dongying depression are supersedure strata of oil and gas exploration. Based on the observation of microscopic fluorescence and homogenization temperature test of fluid inclusions and in combination with the simulation of burial and thermal history, the hydrocarbon charging characteristics of Es₄^x-Ek reservoirs are analyzed. The result shows that Es₄^x-Ek reservoirs in the south slope of Dongying depression experienced one stage of hydrocarbon charging, which is from the Minghuazhen to the present day. However, the Es₄^x-Ek reservoirs in the north slope experienced three stages of hydrocarbon charging, which are the 3rd member of Shahejie period, Guantao period, and Minghuazhen to the present day. The burial depth of the north slope is deeper than that of the south slope. The oil source of Es₄^x-Ek reservoirs in the south slope is overlying Es₃^x and Es₄^x source rocks, whereas the oil source of the north slope contains Es₄^x source rock. The different geological backgrounds, oil sources, and source-reservoir combination patterns lead to the significant differences of hydrocarbon charging characteristics between the south and the north slopes.

Shale gas exists in forms of free state and adsorption state in shale. Micro pore and micro fracture in shale are the main locations of the reservoir space and the drainage channels of the shale gas and the gas content is related to the pore fracture growth degree. So it is very important to study the micro pore and the micro fracture in the shale reservoir. In this paper, based on the results of the field emission scanning electron microscopy, the argon ion polishing and the nuclear magnetic resonance, the micro pore and micro crack morphologies in the Upper Paleozoic in the eastern margin of Ordos Basin are analyzed. The pore size and the development degree of the micro-scale pore, the nano-scale pore and the fracture are quantitatively analyzed. The comprehensive analysis shows that the main reservoir space of shale is the micropore and the microcrack with organic pore as revealed mainly by the argon ion polishing and the clay mineral micro pore as revealed mainly by the scanning electron microscope. The micron pore size is in the range of 1.32~5.58 μm and its average area percent of pore is in the range of 19.48%~23.66%. The average size of the organic micro pore is in the range of 56.51~80.75 nm and its average area percent of pore is in the range of 7.45%~9.66%. The percent of crack is in the range of 0.69%~5.13%. Effective porosity is in the range of 0.25%~1.33%, which accounts for 16%~46% of total porosity. Comprehensive analysis reveals that the shale reservoir of Shanxi of Taitou is the best, because of the relatively low buried depth, the full development of micro-scale pore, the relatively high percentage of crack/micro crack of 56.51~80.75 nm and its average area percent in the range of 7.45% ~9.66%. The proportions of the crack and the movable fluid are 2.18% , 10.82% , respectively, and the mean value of effective porosity is 0.76% amounting to 16%~41% of the total pore. The quantitative study of micro pore and micro crack provides a reliable basis for the further study of shale gas of Upper Paleozoic in this region.

This paper studies the influence of the wetting phase in CO₂ corrosion environment with bottom sediments on the corrosion of pipeline. In the pipeline bottom, the wet analysis is conducted on the composition of brine, the sediment of scaling tendency, the sediment formation and the types of pipeline internal sediment. The electrochemical noise technique and the metallographic analysis are applied for the 20^# low carbon steel in the wet CO₂ environment, with no sediment covered under the potential noise, the current noise and the corrosion resistance noise, and the corrosion morphology is observed. The results show that, compared with the 20^# carbon steel without sediments, the potential noise and current noise have a time-varying volatility in the wet CO₂ environment, and the resistance noise is reduced by 87.5% ~95%. With the sediment removal and a regular monitoring of the corrosion inhibitor corrosion weight loss and corrosion and other parameters in laboratory and field experiments, the regular cleaning deposit and corrosion inhibitor levels of the 20^# low carbon steel sheet, can, respectively, be reduced by 80%, 43%, and 57%, 92% for the point corrosion rate.

Layered structural LiNi_1/3Co_1/3Mn_1/3O₂ is one of the most promising materials used as a cathode for Li-ion battery in electric vehicles, mainly due to the high capacity, the stable structure, the thermal stability and the low cost of LiNi_1/3Co_1/3Mn_1/3O₂. In this review, the structure, the electrochemical performances and the methods for improving its electrochemical performances of LiNi_1/3Co_1/3Mn_1/3O₂, such as doping with other ions, coating with other materials and the preparation of special structural nanomaterials, are included. In recent years, the researchers on Li-ion battery are concerned with various nanomaterials. The electrochemical performances of materials are closely related with the size, the morphology, the porosity, the crystalline features and the specific surface area of the material. Therefore, these effects should be considered for improving the electrochemical performances of LiNi_1/3Co_1/3Mn_1/3O₂ cathodes.

In the context of the scienen and technology development, the extension of university functions and the characteristics of universities, the motivation, the superiority, the ways and the significance of the university science popularization are discussed in this paper. The university is one of the scienen and technology original innovation organizational sources, with a heavy responsibility for cultivating talents and conducting science researches. With abundant scienen and technology knowledge resources, facilities and human resources, the university forms a unique resource system in science popularization. In the prosperity and development of science popularization causes, the university plays an important role in science popularization through participation in various ways and patterns.