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Zirconium base metallic glasses [Zr0.73(Cu0.59Ni0.41)0.27]87Al13 was fabricated by industrial zirconium with low purity and high purity zirconium according to different quality ratios in order to study the effect of raw material purity on the structure and properties of metallic glasses. The results showed that the complete metallic glasses was failed to be fabricate with low purity zirconium. And the compression process was typical brittle fracture with low compressive strength and without plastic strain. The glasses forming ability of low purity zirconium metallic glass with different purity was significantly improved after the addition of yttrium element. The compression experiments showed that the compressive strength and plasticity of metallic glasses were improved, and the microhardness was also increased. It indicates that yttrium element can eliminate the adverse effect of impurity in low purity zirconium on the glasses forming ability of the alloy and improve the structural properties of the metallic glasses.

The effects of different process parameters on the microstructure and mechanical properties of Zr-based bulk metallic glass were studied by using four factors and four levels of orthogonal experiment. Through the observation and analysis of the X-ray diffraction pattern, room temperature compressibility, microhardness distribution and transmission electron micrograph of the [Zr0.72-x(Cu0.59Ni0.41)0.28+x]88-yAl12+y (atomic percent) amorphous alloy with different process parameters, the results show that the compressive strength of the amorphous alloys with composition of [Zr0.73(Cu0.59Ni0.41)0.27]88Al12 and [Zr0.73(Cu0.59Ni0.41)0.27]87Al13 amorphous alloy under the corresponding processing parameters has reached 2411MPa and 1993MPa, and the plastic strain of the alloys is 33.8% and 19.3%. At the same time, through orthogonal analysis, in the four process parameters, the superheat temperature of the melt during the preparation of the alloy mainly affects the compressive strength of the alloy, while the cooling rate of the melt during the preparation of the alloy has a great influence on the plastic properties of the alloy.

There are relevant reports on preparing TiB2 particle reinforced metal matrix composite (MMC) anti-wearing coating by plasma spraying and HVOF spraying methods successfully. The research uses electric arc spraying with low cost and convenient operation to prepare four TiB2 particle reinforced composite coatings with high bonding strength and uniform microstructure. It makes comparative study on elevated temperature erosion actions of coating and 45CT of electric arc spraying. The results indicate the coating has excellent erosion wearing resistance. TiB2 particles in M-TiB2 coating have small size, have good unity with metallic matrix, and are distributed on metallic matrix with high hardness relatively uniformly, and porosity of coating is low. Such MMC coating microstructure feature avoids micro-cutting of coating effectively, and reduces plastic deformation and material transfer of wearing surface. The coating has excellent erosion resistance.

Greenhouse temperature control is a key factor which affects crop growth, and the traditional way of temperature regulation already cannot satisfy the requirements of modern greenhouse: high precision, rapid acquisition and response. The 32-bit EasyARM1138 single chip microcomputer is taken as the main control chip to implement multiple canopy temperature acquisition and control. AT89C52 single chip microcomputer is applied as assisted control chip to implement single greenhouse temperature control. DS18B20 digital temperature sensor is used to collect temperature information in the greenhouse. Through buttons, LCD monitor, GPRS SMS alarm module, and light alarm system with LED and buzzer sound to realize human-computer interaction. Through analyzing of the present condition of greenhouse environment, greenhouse temperature parameters are adjusted to achieve the requirements of crops growth and cultivation development to provide the most suitable temperature environment for crop growth, and increase crop yield and quality.

The experiments were conducted on the changes of sintering performance of one kind of ultra fine-sized iron concentrate with or without being processed by high pressure roll grinding (HPRG). The experimental results indicate that the specific surface area increases from 1723. 0 to 2201. 6 cm2/g when the iron concentrate is processed by HPRG. The permeability of sintering mix increases and the iron concentrate becomes easy to react with CaO reagent at high temperature. The effect gets intensified when iron concentrate and lime are processed together by HPRG. The further studies indicate that compared with the base case, the sinter quality also gets improved, in which the yield of sinter increases from 67.24% to 69. 52% and further to 71. 68%, the tumble index (TD increases from 60. 38% to 62. 13% and further to 64. 45%, and the productivity increases from 1. 42 to 1. 57 t/(m2· h) and further to 1. 62 t/(m2· h) when the iron concentrate is processed by HPRG or is processed with lime together. The metallurgical properties of sinter also get improved when the iron concentrate is pretreated by high pressure roll. The results indicate that it is conducive to the increase of sinter quality and productivity when the iron concentrates are processed by HPRG.

The experiments were conducted on the changes of sintering performance of one kind of ultra fine-sized iron concentrate with or without being processed by high pressure roll grinding (HPRG). The experimental results indicate that the specific surface area increases from 1723. 0 to 2201. 6 cm2/g when the iron concentrate is processed by HPRG. The permeability of sintering mix increases and the iron concentrate becomes easy to react with CaO reagent at high temperature. The effect gets intensified when iron concentrate and lime are processed together by HPRG. The further studies indicate that compared with the base case, the sinter quality also gets improved, inwhich the yield of sinter increases from 67.24% to 69.52 % and further to 71.68 %, the tumble index (TI) increases from 60.38% to 62.13 % and further to 64. 24%, and the productivity increases from 1.42 to 1.57 t/(m2· h) and further to 1. 62 t/(m2· h) when the iron concentrate is processed by HPRG or is processed with lime together. The metallurgical properties of sinter also get improved when the iron concentrate is pretreated by high pressure roll. The results indicate that it is conducive to the increase of sinter quality and productivity when the iron concentrates are processed by HPRG.

Investigation was conducted on roasting properties of pellets with an iron concentrate of complex mineral composition. The results indicated that the pellets of complex mineral composition concentrate required higher preheating temperature and longer preheating time than that of single magnetite concentrate. Therefore, it is difficult for preheated pellets to withstand the mechanical collision in the roasting process in rotary kiln. It was found that after the iron concentrate being subjected to high pressure roll grinding, the specific surface area reached 2029. 1 cm2/g. Consequently, the preheating and roasting temperature of pellets were decreased by 70 and 50 C and preheating and roasting time were decreased by 2 and 4 min, respectively. Meanwhile, the compression strength of preheated and roasted pellets were increased by 200 N for a pellet and 220 N for a pellet, respectively. The mechanism lied in that the increase of specific surface area activated thermal reaction and promoted formation of inter-grain bridge.

The experiments were conducted based on the study of one kind of ultra fine-sized magnetite concentrate with nearly 85% of the material being less than 0.044mm in size. The preliminary study has shown that this iron concentrate has middle ballabitity(K=0.61) because the iron concentrate characterized with flaky and spherical particle shapes. Such features are detrimental to the granulation of green pellets. Much more research work was carried out on how to improve balling performance by processing this magnetite concentrate with high pressure roll grinding (HPRG). The results indicated that newly-created cracks and edges would appear. Specific surface area of iron concentrate would increase from 2161.72 cm2.g-1 (base case) to 2703.51cm2.g-1 and fine particles percentage (-0.044mm) would increase to 94.69%. For the balling performance experiment, the results revealed that the ballability would increase to 1.59. Drop strength of green pellets would increase from 6.1 times/0.5m to 14.7 times/0.5m. Compression strength of green pellets would increase from 10.5N.P-1 to 12.61N.P-1. But break down temperature would decrease from more than 600℃ to 480℃. The whole experiments revealed that HPRG could improve the balling performance of ultra fine-sized magnetite concentrate.

Investigation was conducted on roasting properties of pellets with an iron concentrate of complex mineral composition. The results indicated that the pellets of complex mineral composition concentrate required higher preheating temperature and longer preheating time than that of single magnetite concentrate. Therefore, it is difficult for preheated pellets to withstand the mechanical collision in the roasting process in rotary kiln. It was found that after the iron concentrate being subjected to high pressure roll grinding, the specific surface area reached 2029. 1 cm 2/g. Consequently, the preheating and roasting temperature of pellets were decreased by 70 and 50 °C and preheating and roasting time were decreased by 2 and 4 min, respectively. Meanwhile, the compression strength of preheated and roasted pellets were increased by 200 N for a pellet and 220 N for a pellet, respectively. The mechanism lied in that the increase of specific surface area activated thermal reaction and promoted formation of inter-grain bridge.

The timing of the closure of the Bangong‐Nujiang Tethyan Ocean is highly controversial. An important reason for this is that the sedimentological work within the Bangong‐Nujiang suture zone is not sufficient. In this study, based on the U‐Pb zircon dating of turbiditic sandstone and tuff interlayers, we determine the existence of Aptian flysch (ca. 126–113 Ma) in the middle and western segments of the Bangong‐Nujiang suture zone. Further analysis shows that the Aptian flysch was deposited in a trench environment. In space, from the Mabujia Co area in the western segment to the Kama area in the middle segment, the outcrop extent of the Aptian flysch spans nearly 300 km from east to west. These results indicate that the Bangong‐Nujiang Tethyan Ocean had not fully closed by the end of Aptian time, and its oceanic slab was still subducting. Based on this new discovery, and the results of previous studies, we believe that the middle and western segments of the Bangong‐Nujiang Tethyan Ocean closed between 113 and ca. 92 Ma nonmarine deposition of the Jingzhushan Formation, which lies in angular unconformity above the flysch. We determined the existence of Aptian flysch (ca. 126–113 Ma) in the middle and western segments of the Bangong‐Nujiang suture zoneThe Aptian flysch represents north‐derived trench deposits of the north‐dipping Bangong‐Nujiang Tethyan subduction zoneThe middle and western segments of the Bangong‐Nujiang Tethyan Ocean closed during ca. 113–92 Ma