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The physics of spin-1/2 xy model with four-site exchange interaction on the kagome lattice - Nguyen Thi Kim OanhHơn ba thập kỉ trƣớc, Fazekas và Anderson đã tìm ra một trong các trạng thái cơ bản của spin, trạng thái spin lỏng lƣợng, với nhiều đặc điểm kì lạ. Sau nhiều năm tìm kiếm, gần đây đã xuất hiện các thí nghiệm nhƣ những minh chứng rõ ràng về sự tồn tại của trạng thái này ở các hệ frustrated spin. Đáng tiếc là các mô hình vi mô mô tả sự tồn tại của...
8 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 650 | Lượt tải: 0
Spread of interaction in nanocomposite hard/soft nanostructured magnets - Nguyen Trung HieuMonte-Carlo 3D simulation has been performed to study the effect of spreading of the exchange interaction in two-phase hard/soft nanocomposite nanostructured magnetic materials. The obtained demagnetization curves closely described the experimental ones. The energy product can be enhanced by 40 % more in the case of 50 vol.% of the soft phase co...
8 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 623 | Lượt tải: 0
Study on influence of temperature and duration of hydrothermal treatment to properties of nano ferrite nife2o4 materials - Tran Quang DatHạt nano siêu thuận từ NiFe2O4 đã được tổng hợp bằng phương pháp phun sương đồng kết tủa, kết hợp với ủ thủy nhiệt. Đây là phương pháp có khả năng chế tạo được bột nano với chất lượng và năng suất cao. Quá trình tổng hợp mẫu, khảo sát sự hình thành tinh thể ferrite cho thấy sự phụ thuộc của tính chất vật liệu vào nhiệt độ và thời gian thủy nhiệt...
8 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 948 | Lượt tải: 0
Studying the effects of vacancies on the melting temperature of agce alloy - Dang Thanh HaiFig.1 presents the ratio of (TmAB−TmABvacancy)=TmAB of AgCe, Ag2Ce and Ag3Ce alloys under various pressures. This ratio is a function of pressure, the value of this ratio decreases when the pressure increases. It is concluded from the Fig.1 that the vacancy contribution is negligible162 DANG THANH HAI, VU VAN HUNG AND GIANG THI HONG on the melti...
8 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 777 | Lượt tải: 0
Synthesis, characterization and corrosion inhibitive ability of composites silica – polypyrrole - Vu Thi Hai VanFigure 7 shows Tafel curves of steel coated with PVB and steel coated with PVB containing 10 % SP1, SP2, SP3 and SP4 in 3 % NaCl solution after 48 hours. The values of corrosion potential (Ecorr), corrosion current density (icorr), anodic and cathodic Tafel constants (βa, βc), polarization resistance (Rp) are given in table 3. Corrosion pote...
7 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 815 | Lượt tải: 0![Interaction between triphenylphosphine or 1,2-Bis(diphenylphosphino)ethane with some complexes K[PtCl3(olefin)] (olefin: methyleugenol, safrole, isopropyl eugenoxyacetate)](https://s2.tai-lieu.com/pwz9k16xr4jr01yq7rzg033izykdsbez/thumb/2020/12/03/interaction-between-triphenylphosphine-or-12-bisdiphenylphos_njEyr5ay2h.jpg)
Interaction between triphenylphosphine or 1,2-Bis(diphenylphosphino)ethane with some complexes K[PtCl3(olefin)] (olefin: methyleugenol, safrole, isopropyl eugenoxyacetate)The interaction between K[PtCl3(olefin)] (olefin: methyleugenol, safrole and isopropyl eugenoxyacetate) with triphenylphosphine (TPP) and 1,2-bis(diphenylphosphino)ethane (DPPE) have been studied for the first time. The results show that TPP and DPPE can coordinate with Pt(II) very favorably and they are able to replace the olefin in complex...
6 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 928 | Lượt tải: 0
Extractive spectrophotometric methods for determination of ciprofloxacin in pharmaceutical formulations using sulfonephthalein acid dyesThis article reports the use of BCG, BPB and BTB as an anionic dyes for the extractive spectrophotometric determination of ciprofloxacin. The performance order of the proposed methods is BTB > BCG > BPB. No interference from common excipients was encountered. The proposed methods are found to be simple, sensitive, selective, accurate, precis...
8 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 735 | Lượt tải: 0
Extraction of Lycopene from Gac Fruit (Momordica cochinchinensis Spreng) and Preparation of NanolycopeneNanolycopene was prepared by emulsification/solvent evaporation method using an Ultra-Turrax homogenizer. The feeding composition of sample S2 included 1 mg of BHT as antioxidation agent (table 2) while sample S1 was prepared without any anti-oxidation agent. The HPLC analysis showed that the lycopene content of S1 nanoparticles was 9.9 % whi...
6 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 977 | Lượt tải: 0
A computational study on structure and stability of nitrogen-Doped titanium clusters TinN (n = 1-10) - Le Nguyen Ngoc LanSome concluding remarks are resulted from this theoretical study as follows: - The most stable isomers may have spin state ranging from doublet to quartet to sextet. - The ground-state structure of these clusters are built up by the nitrogen-addition rule. Thus, the nitrogen atom prefers to stay on surface of the clusters. - Doping with one...
6 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 713 | Lượt tải: 0
Oxidation of benzyl alcohol to benzaldehyde over MnOx/sepiolite catalysts - Nguyen Thi NhuWith XRD pattern of sepiolite and MnOx/sepiolite analyzed; manganese oxide existed as Mn3O4 on sepiolite nanofibers after the precipitation from nitrate salt. The morphology of sepiolite was slightly modified after calcincation process. The Mn3O4 particles were well distributed on the surface of the fibrous sepiolite and caused slight decreas...
5 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 789 | Lượt tải: 0
