Ho Chi Minh City, Vietnam
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Duc D.V.,Institute of Physics | Giao N.M.,Center for Nuclear Techniques | Dung T.T.,Thu Dau Mot University
International Journal of Theoretical Physics | Year: 2014

The mass spectrum for spinor fields in extra dimensions is considered within the framework of the mass creation mechanism proposed in our previous works (Duc and Giao 2013; Duc and Giao J. Mod. Phys. 4(N7), 991, 2013; Duc et al. J. Phys Sci. Appl. (USA) 4(N1), 60, 2014; Duc and Giao J. Mod. Phys. 5(N6), 2014). It is shown that a single spinor field in the whole space-time with extradimensions corresponds to a set of multiplets of effective spinor fields in ordinary 4-dimensional space-time with masses obeying the sum rule expressed in terms of metric for extradimensions and parameter functions dictated from the periodicity conditions. © 2014 Springer Science+Business Media New York.


Le X.T.,Center for Nuclear Techniques | Le Q.H.N.,Center for Nuclear Techniques | Pham N.D.,Cat Tien National Park | Duong V.H.,Hanoi University | And 3 more authors.
Mycological Progress | Year: 2012

The polypore genus Tomophagus was created to segregate one peculiar species, Ganoderma colossum, from the genus Ganoderma. Recent molecular studies have established the validity of this monotypic genus. Here we report the discovery of a second species of Tomophagus, T. cattienensis sp. nov., from Cat Tien National Park in southern Vietnam, a lowland forest that has been designated as a Biosphere Reserve by the United Nations Educational, Scientific and Cultural Organization (UNESCO). Recognition of this new species is based on combined evidence from morphology, cultural characteristics, and ITS rDNA barcodes. The discovery of this new species may have implications for the discovery of novel bioactive compounds for pharmaceutical use and/or for the pulp industry. © 2011 German Mycological Society and Springer.


Duc D.V.,Institute of Physics | Giao N.M.,Center for Nuclear Techniques
International Journal of Theoretical Physics | Year: 2016

We propose a mechanism for explaining the originality of charge creation based on some specific assumptions related to space – time extra dimensions. It holds that the existence and the compactification of extra dimensions are the origin for creating the interaction charge in ordinary 4 – dimensional space – time. © 2015, Springer Science+Business Media New York.


Luan L.Q.,Center for Nuclear Techniques | Uyen N.H.P.,Center for Nuclear Techniques | Ha V.T.T.,Saigon Thuy Canh Corporation
Scientia Horticulturae | Year: 2012

The basic medium containing half-strength of MS basal medium, full-strength of vitamin MS, 20mll -1 coconut water and 2gl -1 activated charcoal supplemented with 170mgl -1 NaH 2PO 4, 10mgl -1 2,4D and 0.1mgl -1 TDZ was found to be appropriate for callus formation of Paphiopedilum delenatii and Paphiopedilum callosum. Additional supplementation with 2.0mgl -1 BA and 0.1mgl -1 TDZ in combination with NaH 2PO 4 and 50mgl -1 oligochitosan enhanced PLB multiplication. Shoot bud proliferation of tested orchids was optimally increased in a basic medium supplemented with 0.5mgl -1 TDZ and 0.1mgl -1 NAA. The basic medium supplemented with NaH 2PO 4 was suitable for plantlet regeneration. In addition, the values of LD 50 (lethal dosage of 50% irradiated samples) of protocorm like bodies, shoot buds and in vitro plantlets were determined for P. delenatii (20Gy, 23.7Gy and 38Gy, respectively) and P. callosum (23Gy, 27.1Gy and 40.4Gy, respectively). No variant line was found for both orchid samples irradiated by gamma-rays, whereas 24 variant lines (which are divided among the two tested Paphiopedilum) were screened for samples irradiated by C 6+ ion-beams (3Gy). The genetic relationships among six generated variant lines and wild types were analyzed using RAPD techniques. Irradiation-induced variation is promising for developing new mutant varieties of Paphiopedilum. © 2012 Elsevier B.V.


Luan L.Q.,Center for Nuclear Techniques | Ha V.T.T.,Saigon Thuy Canh Corporation | Uyen N.H.P.,Center for Nuclear Techniques | Trang L.T.T.,Center for Nuclear Techniques | Hien N.Q.,Vietnam Atomic Energy Commission
Journal of Agricultural and Food Chemistry | Year: 2012

Degraded alginate compounds with molecular weights of 7-26, 40-77, or 11-26 kDa were obtained by γ irradiation, hydrogen peroxide (5% H 2O 2) treatment, or a combination treatment involving ionizing radiation and H 2O 2, respectively. The 14 kDa oligoalginate, prepared by the combined method, promoted the growth of mustard greens and lettuce at an optimal concentration of 75 mg/L. The growth promotion effects of the oligoalginate prepared by γ irradiation in the presence of H 2O 2were statistically equivalent to those of the oligoalginate prepared by γ irradiation only. The combination of γ irradiation and H 2O 2reduced the required irradiation dosage by a factor of 9 relative to the oligoalginate produced by γ irradiation only. The combination treatment (γ irradiation/H 2O 2) may be carried out on a large scale at low cost to produce oligoalginate for use as a plant growth promoter in agricultural industries. © 2012 American Chemical Society.


Dung T.Q.,Center for Nuclear Techniques
International Journal of Nuclear Energy Science and Technology | Year: 2010

A simple gamma technique based on using two identical detectors has been studied and applied to assay radwaste drums. The characterisation and performance of the measurement system are discussed for practical application. The results show that the proposed technique successfully solved the problem of assay of unusual radwaste drums (as released from Dalat Nuclear Reactor, Vietnam). © 2010 Inderscience Enterprises Ltd.


Niimura N.,Ibaraki University | Kikuchi K.,Ibaraki University | Tuyen N.D.,Ibaraki University | Tuyen N.D.,Center for Nuclear Techniques | And 2 more authors.
Journal of Environmental Radioactivity | Year: 2015

We conducted an elution experiment with contaminated soils using various aqueous reagent solutions and autoradiography measurements of contaminated bamboo shoots and shiitake mushrooms to determine the physical and chemical characteristics of radioactive Cs from the Fukushima Daiichi Nuclear Power Plant accident. Based on our study results and data in the literature, we conclude that the active Cs emitted by the accident fell to the ground as granular non-ionic materials. Therefore, they were not adsorbed or trapped by minerals in the soil, but instead physically adhere to the rough surfaces of the soil mineral particles. Granular Cs* can be transferred among media, such as soils and plants. The physical properties and dynamic behavior of the granular Cs* is expected to be helpful in considering methods for decontamination of soil, litter, and other media. © 2013 The Authors.


Luan L.Q.,Center for Nuclear Techniques | Uyen N.H.P.,Center for Nuclear Techniques
International Journal of Biological Macromolecules | Year: 2014

The (1→3)-β-d-glucan extracted from the yeast cell wall was irradiated by γ-rays from a Co-60 source at dose range of 100-300kGy in a swelling condition of 10, 15 and 20% for degradation. The water-soluble contents of irradiated samples obtained by 10% (1→3)-β-d-glucan mixture increased from 25.89 to 66.71% by the increasing of irradiation doses from 100 to 300kGy. While the molecular weight of the water-soluble (1→3)-β-d-glucan was found to be decreased from 48.13 to 10.77kDa. In the UV-spectra of irradiated water-soluble (1→3)-β-d-glucan, a new peak appeared at 265nm with the intensity increased by the increase of the dose. The IR spectra of irradiated (1→3)-β-d-glucan were recognized by a decrease of the peak intensity at 1156cm-1 indicated to COC glycosidic linkages with the increasing of irradiation dose. In addition, radiation degraded (1→3)-β-d-glucan with Mw about 18kDa prepared at the dose of 250kGy displayed a strongly promotion effect on the growth of mustard green and the optimum concentration of the degraded (1→3)-β-d-glucan was found to be about 75mgl-1. Thus, the degraded (1→3)-β-d-glucan prepared by radiation technique displayed as a promising, safety and high effective plant growth promoter for agriculture application. © 2014 Elsevier B.V.


Suc N.V.,Ho Chi Minh City University of Technology and Education | Bich T.T.,Center for Nuclear Techniques
Radiochimica Acta | Year: 2013

This paper presents a simple and accurate method for determination of uranium isotopes (234U and 238U) in seawater samples using alpha spectrometry. Uranium is pre-concentrated from seawater samples via adsorption on hydrotalcite at pH 6.5. The absorbent is dissolved into 50 ml of 8M HNO3; then filtered through a Dowex-1 column. U(VI) in the elution solution is reduced to U(IV) using zinc metal in 4M solution of HCl and then co-precipitated with LaF3. The chemical separation efficiency is found to be 97.12±2.68%, eliminating the need of using 232U tracer in other published methods. This method is validated via comparison with results obtained using inductively coupled plasma mass spectrometry (ICP-MS) and neutron activation analysis (NAA) for three seawater samples. © by Oldenbourg Wissenschaftsverlag, München.


PubMed | Center for Nuclear Techniques
Type: Journal Article | Journal: Journal of agricultural and food chemistry | Year: 2012

Degraded alginate compounds with molecular weights of 7-26, 40-77, or 11-26 kDa were obtained by irradiation, hydrogen peroxide (5% H(2)O(2)) treatment, or a combination treatment involving ionizing radiation and H(2)O(2), respectively. The 14 kDa oligoalginate, prepared by the combined method, promoted the growth of mustard greens and lettuce at an optimal concentration of 75 mg/L. The growth promotion effects of the oligoalginate prepared by irradiation in the presence of H(2)O(2) were statistically equivalent to those of the oligoalginate prepared by irradiation only. The combination of irradiation and H(2)O(2) reduced the required irradiation dosage by a factor of 9 relative to the oligoalginate produced by irradiation only. The combination treatment ( irradiation/H(2)O(2)) may be carried out on a large scale at low cost to produce oligoalginate for use as a plant growth promoter in agricultural industries.

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