Ab initio (MP2) and density functional theory (DFT) methods were used to examine nine isomers of the doublet BN(4) species with the 6-311 + G(d) basis set. To our knowledge, these nine structures are all first reported here. Energy analysis indicates that the C(2v) branched structure is the global minimum of potential energy surface. Research results show that the C(2v) branched, the cis-linear, the C(4v) pyramidal, and the C(S) five-membered ring structures are likely to be stable and to be observed experimentally. Among these four kinetically stable species, the last three are suitable to be used as potential precursors of HEDMs due to their high dissociation energies. However, the C(2v) bent, the trans-linear, the D(2) bicyclic, the C(2v) four-membered ring, and the C(2v) cage structures are kinetically unstable due to their low dissociation or isomerization barriers. Two synthesis pathways of the C(2v) branched isomer were located. It seems more feasible to synthesize this species by linear NBN and N(2).

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Welding experiments were made with δ=14mm, 16MnR steel by three welding methods, manual electric arc welding, automatic submerged arc welding and semi-auto solid-core CO2 shielded arc welding, and weld joint test with samples from every welding specimen. The properties of welding joint were analyzed by three welding methods and in every position of welding, concluded that brittlement problems in heat affected zone arise from the CO2 shielded arc welding, it is because of the heat damage of alloy elements of weld joint metal while using CO2 shielded arc welding, but the strength of the weld joint is high because of its high fusion ratio. So for improving the mechanical properties of weld joints.it had better accelerate the cooling rate of weld bead and decrease the heat input of welding.

The course Environmental Quality Management by ISO 14001 is a special course offered to students majoring in Environmental Engineering. It aims to let students grasp basic knowledge on ISO 14001, including mode of ISO 14001, content of ISO 14001, planning, establishing and performing of it. ISO 14000 (made by International Standard Organization), has been enacted to protect the environment through environmental quality management, among which ISO14001 is the most important section. With increasing damage of the environment across the world, ISO 14001 was revised in 1996, the new version was carried out in 2006. Therefore, this course requires construction in accordance with the revised new ISO 14001 version to keep up with environment quality management nowadays.

In this work, MSWI (municipal solid waste incineration) fly ash is used to make FA ceramic brick, together with clay, fried clay and limestone. Microstructure of the product as a function of sintering temperature was studied using SEM (Scanning Electron Microscope). It was found that microstructure is strengthened with the increase of temperature, and porosity reduced. In addition, content of glass phases increase and particles are more closely cemented together as sintering temperature increases from 900 to 1050°C, which is conducive to solidification of heavy metals in the body.