In Vietnam, bio-fuel has been studied and attracted attention of scientists under the concrete support policy from government. Although general diesel engines and especially marine diesel engines are one of main energy consumption factors and influent to environmental pollution, but bio-fuel has been still in theory researches or reached to small production. It leads to very few or nearly empty application of biodiesel in maritime field. Currently, biodiesel has been imported always and it results in high cost in use.

The modification of Ilmenite by H₂SO₄ solution was carried out. ICP-MS technique was used to determine ratio of Fe/Ti of Ilmenite samples. Different techniques such as XRD, SEM were used to characterize Ilmenite samples. The degradation of reactive yellow 3RS using modified Ilmenite as a heterogeneous photo-Fenton catalyst was investigated. The obtained results indicate that modified Ilmenite has high catalytic activity. The degradation efficiency of 96% under UV and 93% under Vis for reactive yellow 3RS can be attained.

The modification of Ilmenite by H₂SO₄ solution was carried out. ICP-MS technique was used to determine ratio of Fe/Ti of Ilmenite samples. Different techniques such as XRD, SEM were used to characterize Ilmenite samples. The degradation of reactive yellow 3RS using modified Ilmenite as a heterogeneous photo-Fenton catalyst was investigated. The obtained results indicate that modified Ilmenite has high catalytic activity. The degradation efficiency of 96% under UV and 93% under Vis for reactive yellow 3RS can be attained.

The fly ash from Pha Lai power plant was modified by three types of silane coupling agent (SCA). The thermal oxidation stability of the composites was determined by thermal gravimetric analysis (TGA). The morphology of modified fly ash and LDPE/EVA/FA composites was analyzed by scanning electron microscopy (SEM). Besides, the mechanical properties of LDPE/EVA/FA composites were also studied.

The polymer composites based on low-density polyethylene (LDPE), ethylene vinyl acetate copolymer (EVA) and fly ash (FA) without and with vinyltrimetoxysilane (VTMS) modification were prepared by melt mixing in a Haake Rheomixer. The FT-IR spectra indicated the bonds between LDPE/EVA and FA modified by vinyltrimethoxysilane were dipole - dipole interaction and hydrogen bonding. Both dynamic storage modulus (G’) and loss modulus (G’’) of the LDPE/EVA/FA-VTMS composites were higher than those of the LDPE/EVA/FA composites.

Here we repor t on the modification of fly ash (FA) with vinyltr iethoxysilane (VTES) in order to enhance the dispersibility and avoid the agglomeration. FA was treated with nitr ic acid before the modification with VTES. The str ucture of fly ash par ticles before and after the modification was character ized by several sophisticated techniques including Four ier transfor m infra-red spectrum (FT-IR), ther mogravimetr ic analysis (TGA), field emission scanning electron microscopy (FE-SEM)and size distr ibution analysis.

The polymer composites based on low-density polyethylene (LDPE), ethylene vinyl acetate copolymer (EVA) and fly ash (FA) without and with organic modification were prepared by melt mixing in a Haake Rheomixer. The dielectric strength of LDPE/EVA/FA and LDPE/EVA/modified FA (MFA) composites was lower than that of LDPE/EVA blend. The LDPE/EVA/MFA composites have the dielectric strength higher than the LDPE/EVA/FA composites at the same content of FA.

The polymer composites of low-density polyethylene (LDPE) and poly(ethylene-co-vinyl acetate) (EVA) blends filled by fly ash (FA) with different content were prepared by melt mixing in a Haake Rheomixer. The relative melt viscosity of the composites is increased and tensile property of the composites is decreased with increasing the FA content. When the fly ash modified with VTMS silane (FA-VTMS), the relative melt viscosity of the LDPE/EVA/FA-VTMS composites is lower the LDPE/EVA/FAs composites.

Trong bài báo này, tác giả đã thực hiện một số thí nghiệm nghiên ảnh hưởng của một số thông số sóng siêu âm đến đường kính hạt niken khi gia công bằng hệ thống tia lửa điện kết hợp với sóng siêu âm. Kết quả đưa ra được mối quan hệ giữa công suất và tần số siêu âm với đường kính hạt niken.

Quá trình nhiệt luyện hợp kim Cu-15Ni-8Sn bao gồm nung hợp kim đến nhiệt độ 820oC, giữ trong khoảng thời gian nhất định để các nguyên tố hợp kim hòa tan vào đồng, tạo nên dung dịch rắn quá bão hòa một pha đồng nhất, sau đó nguội nhanh trong nước lạnh để giữ dung dịch ở nhiệt độ thường, tiếp theo hóa già hợp kim ở 4500C trong 2 giờ.  Từ dung dịch rắn quá bão hòa, khi hóa già, nguyên tố hợp kim tách ra, tạo nên các vùng tổ chức spinodal nhỏ mịn, tăng bền cho hợp kim.