• Axion production in unpolarized and polarized γe− collisionAxion production in unpolarized and polarized γe− collision

    Abstract. Axion production in unpolarized and polarized γe− collision are considered in detail using the Feynman diagram method. The cross-sections are presented and numerical evaluations are given. The results show that the axion can be dark matter of the universe. Some estimates for experimental conditions are given from our results.

    pdf7 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 444 | Lượt tải: 0

  • Đánh giá độ nhậy của phản ứng minh họa đặc tính dị phân của hiđropeoxit (H2O2)Đánh giá độ nhậy của phản ứng minh họa đặc tính dị phân của hiđropeoxit (H2O2)

    Tóm tắt. Bài báo trình bày nội dung và cách tiến hành hai thí nghiệm minh họa đặc tính dị phân của hiđro peoxit (H2O2) và sự chuyển dịch cân bằng oxihoá - khử. Khi đánh giá độ nhậy của phản ứng theo hai phương pháp, chúng tôi đã thu được các kết quả phù hợp. Trong các trường hợp nghiên cứu cũng cho thấy hàm phân bố chuẩn luôn cho kết quả phù hợp tố...

    pdf9 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 547 | Lượt tải: 0

  • Nghiên cứu lí thuyết khả năng hấp phụ CO2 bằng vật liệu MOF-5 khung kim loại Cu, Co tẩm kim loại kiềmNghiên cứu lí thuyết khả năng hấp phụ CO2 bằng vật liệu MOF-5 khung kim loại Cu, Co tẩm kim loại kiềm

    Tóm tắt. Sự hấp phụ CO2 bởi vật liệu hữu cơ khung kim loại MOF-5 (khung kim loại Co cũng như Cu) được nghiên cứu bởi phương pháp phiếm hàm mật độ GGA-DFT với phiếm hàm tương quan trao đổi PBE. Kết quả nghiên cứu cho thấy MOF-5 được tẩm thêm kim loại kiềm (đặc biệt là Li) là vật liệu hấp phụ CO2 đầy triển vọng, năng lượng hấp phụ CO2 trở nên âm ...

    pdf13 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 401 | Lượt tải: 0

  • Πgp-Regularity of rationnal sequence topological spaceΠgp-Regularity of rationnal sequence topological space

    1. Introduction In 2012, L. N.T. Nhon and B.Q. Thinh introduced the notations of πgp-normal and πgp-regular spaces in the Journal of Advanced Studies in Topology, see [4]. From theorem 3.5 in [4], we have the following theorems: Theorem 1.1. If X is a T1-space and has πgp-normality, then X has πgp-regularity. Theorem 1.2. If X is finite T1-spa...

    pdf7 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 364 | Lượt tải: 0

  • Study on fluctuation of species composition of corn insect pests in Gia Lam, Hanoi, in 2010 - 2011Study on fluctuation of species composition of corn insect pests in Gia Lam, Hanoi, in 2010 - 2011

    Abstract. The relationship between corn insect pests, geographical location and time of the year was studied. Of the total number of species, 32.26% were of the order Lepidoptera (10 species) and 6.46% were of the order Homoptera. Thirty-one, 28 and 27 species of insects which feed on corn were found in the villages of Phu Dong, Van Duc and Phu...

    pdf9 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 384 | Lượt tải: 0

  • Study on the removal of phenol from aqueous solution by peroxide oxidation over pillar claysStudy on the removal of phenol from aqueous solution by peroxide oxidation over pillar clays

    Abstract. In this work, from Bent-CD, refined bentonite (Bent-TC) was prepared using the wet method and the pillared bentonites Bent-Al, Bent-Al/Fe and Bent-Al/Cu were synthesized by the intercalation of Al, Al/Fe and Al/Cu polycation pillars into the interlayer channels of bentonite solid, respectively. The catalytic activity of these pillared...

    pdf6 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 419 | Lượt tải: 0

  • Analyzing 13C-NMR spectra of several polysubstituted quinolinesAnalyzing 13C-NMR spectra of several polysubstituted quinolines

    Abstract. The NMR spectra of 15 novel quinolines containing 11 - 34 carbon atoms and bearing substituents such as hydroxyl, sunfo, chloro, bromo, amino, azo and carboxymetoxy groups were recorded in DMSO at 298 - 300 K. For seven quinolines, the 13C-NMR signals were assigned on the basis of an analyzation of the cross peaks in the HSQC and HMBC...

    pdf6 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 399 | Lượt tải: 0

  • Synthesis of several aromatic aldazinesSynthesis of several aromatic aldazines

    Abstract. Ten aromatic aldazines: 4-nitrobenzal-, 3-nitrobenzal-, 2-nitrobenzal-, 4-dimethylaminobenzal-, 4-methoxybenzal-, 3-methoxybenzal-, 4-fluorobenzal-, 4-chlorobenzal-, 4-bromobenzaldazine and 7-carboxymethoxy-6-hydroxy-3-sulfoquinolin-5-carbaldazine, were synthesized by condensing two equivalents of an appropriate aldehyde with one equi...

    pdf6 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 667 | Lượt tải: 0

  • The influence of some environmental factors on the basic anthropometric indexes of students in hanoi secondary schoolsThe influence of some environmental factors on the basic anthropometric indexes of students in hanoi secondary schools

    Abstract. Study was carried out involving 1200 students (600 male and 600 female) aged 12 to 15. They were enrolled in 3 suburban Hanoi schools and 3 urban Hanoi schools. The results show that in general, the basic anthropometric indexes of suburban Hanoi students are not higher than those of urban Hanoi students. For reasons that effect to ant...

    pdf6 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 471 | Lượt tải: 0

  • Optimising in vitro culture and Agrobacterium tumefaciens-mediated transformation protocols of tobacco BY-2 cellsOptimising in vitro culture and Agrobacterium tumefaciens-mediated transformation protocols of tobacco BY-2 cells

    Abstract. In order to set up a system for production of recombinant proteins using suspension cell culture of Nicotiana tabacum cv. Bright Yellow 2 (BY-2), in vitro culture and genetic transformation protocols of such cells were optimised at the laboratory of Plant Cell Biotechnology, Institute of Biotechnology. Our experiments indicated that t...

    pdf10 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 368 | Lượt tải: 0