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A QUANTITATIVE STUDY ON ENHANCEMENT OF TYPE Ⅱ PHOTOSENSITIZED OXIDATION REACTION RATE BY HEAVY WATER
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作者 Xian Fu ZHANG Hui Jun XU Institute of Photographic Chemistry,Academia Sinica,Beijing,100101 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第8期715-718,共4页
A method for quantitative evaluating the enhancement of the rate of Type Ⅱ photosensitized oxidation by D_2O was suggested. The effect of substrate concentration on this process was also discussed.
关键词 A QUANTITATIVE STUDY ON ENHANCEMENT OF TYPE PHOTOSENSITIZED OXIDATION REACTION RATE BY heavy water RATE
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Characteristics of a heavy water photoneutron source in boron neutron capture therapy 被引量:1
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作者 Danial Salehi Dariush Sardari M. Salehi Jozani 《Chinese Physics C》 SCIE CAS CSCD 2013年第7期88-92,共5页
Bremsstrahlung photon beams produced by medical linear accelerators are currently the most commonly used method of radiation therapy for cancerous tumors. Photons with energies greater than 8-10 MeV potentially genera... Bremsstrahlung photon beams produced by medical linear accelerators are currently the most commonly used method of radiation therapy for cancerous tumors. Photons with energies greater than 8-10 MeV potentially generate neutrons through photonuclear interactions in the accelerator's treatment head, patient's body, and treat- ment room ambient. Electrons impinging on a heavy target generate a cascade shower of bremsstrahlung photons, the energy spectrum of which shows an end point equal to the electron beam energy. By varying the target thickness, an optimum thickness exists for which, at the given electron energy, maximum photon flux is achievable. If a source of high-energy photons i.e. bremsstrahlung, is conveniently directed to a suitable D20 target, a novel approach for production of an acceptable flux of filterable photoneturons for boron neutron capture therapy (BNCT) application is possible. This study consists of two parts. 1. Comparison and assessment of deuterium photonuclear cross section data. 2. Evaluation of the heavy water photonuclear source. 展开更多
关键词 BNCT photoneutron source LINAC heavy water
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Vibronic effect study of ^(1)A_(2) state of H_(2)O and D_(2)O
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作者 张倍源 王礼涵 +5 位作者 朱剑辉 徐卫青 马子茹 赵小利 吴勇 朱林繁 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期395-399,共5页
The generalized oscillator strengths of the dipole-forbidden excitations of the ^(1)A_(2) of H_(2)O and D_(2)O were calculated with the time dependent density functional theory,by taking into account the vibronic effe... The generalized oscillator strengths of the dipole-forbidden excitations of the ^(1)A_(2) of H_(2)O and D_(2)O were calculated with the time dependent density functional theory,by taking into account the vibronic effect.It is found that the vibronic effect converts the dipole-forbidden excitation of the ^(1)A_(2) into a dipole-allowed one,which enhances the intensities of the corresponding generalized oscillator strength in the small squared momentum transfer region.The present investigation shows that the vibronic effect of H_(2)O is slightly stronger than that of D_(2)O,which exhibits a clear isotopic effect. 展开更多
关键词 water heavy water generalized oscillator strength vibronic effect isotope effect
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The Gravito-Chemical Bond and Structures of Hydrocarbons and Water Molecules with Real Magnetic Charges
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作者 Robert A. Sizov 《Open Journal of Physical Chemistry》 2021年第4期220-240,共21页
Experimental and theoretical studies of the author (period: 1968-present) have shown that true sources of </span><span style="font-family:"">the </span><span style="font-family... Experimental and theoretical studies of the author (period: 1968-present) have shown that true sources of </span><span style="font-family:"">the </span><span style="font-family:"">magnetic field are magnetic fundamental particles (magnetic charges), and not moving electrons. The main reason for <span>ignoring real magnetic charges, as well as true antielectrons in physical</span> science is the hard conditions for confinement of these particles in atoms and substance</span><span style="font-family:"">s</span><span style="font-family:"">, which </span><span style="font-family:"">is </span><span style="font-family:"">radically different from the confinement of electrons. Magnetic charges together with electric charges form the shells atoms which are <span>electromagnetic, and not electronic. Namely</span></span><span style="font-family:"">,</span><span style="font-family:""> electromagnetic shells are</span><span style="font-family:""> sources of gravitational field which is </span><span style="font-family:"">a </span><span style="font-family:"">vortex electromagnetic field and de<span>scribed by the vortex</span></span><span style="font-family:""> rot [<i>E</i> - <i>H</i>]</span><span style="font-family:"">. Depending on the state polarization o</span><span style="font-family:"">f vortex vectors </span><span style="font-family:"">rot [<i>E</i> - <i>H</i>]</span><span style="font-family:""> in compositions of atomic gravitational fields it </span><span style="font-family:"">is </span><span style="font-family:"">subdivided into paragravitational (PGF) and ferrogravitational fields </span><span style="font-family:"">(FGF). The overwhelming number of atoms emits PGF. Between the masses (bodies, atoms, nucleons and others) emitting PGF areas of negative gravitational “Dark Energy” are realized the forces of which press the masses towards each other. Namely</span><span style="font-family:"">,</span><span style="font-family:""> the compression of atoms by the forces of paragravitational “Dark Energy” underlies the chemical bond. The exception here is the ionic bond in ionic crystals. However, all ions have electromagnetic shells that generate the gravitational field. Consequently, ionic bonding is a relatively rare addition to gravito-chemical bond processes. The direct gravito-chemical bond of carbon atom</span><span style="font-family:"">s</span><span style="font-family:""> with hydrogen (<sup>1</sup>H) is physically forbidden due to </span><span style="font-family:"">the </span><span style="font-family:"">manifestation of the effect of ferrogravitational levitation between them and the repulsion of atoms from each other. Paradoxically, but all existing ideas about the structural device of hydrocarbons are based on such physically forbidden bonds which, moreover, must be realized through ionic <span>bonds which in reality do not exist. Chemical bonding of carbon and hydrogen </span>atoms to form hydrocarbons molecules is possible only if the hydrogen atoms are in the molecular form (<sup>1</sup>H<sub>2</sub>). In the composition of water, within the framework of the chemical formula H<sub>2</sub>O, two stable isomorphic molecular structures are formed. The chemical bond in the first structure is similar to the hydrocarbon scenario described above, </span><span style="font-family:""><i></span><i><span style="font-family:"">i.e.</span></i><i><span style="font-family:""></i></span></i><span style="font-family:""> in the process of combining paragravitational oxygen with a hydrogen molecule <sup>1</sup>H<sub>2</sub>. The second molecular structure in water is <span>formed under conditions of ferropolarization of the gravitational field of</span> oxygen atom</span><span style="font-family:"">s</span><span style="font-family:""> under the influence of FGF of neighboring <sup>1</sup>H atoms. In this case, the chemical bond is realized under the conditions of ferropolarization</span><span style="font-family:""> </span><span style="font-family:"">of the vortex vectors </span><span style="font-family:"">rot [<i>E</i> - <i>H</i>]</span><span style="font-family:""> of the gravitational fields of all atoms in</span><span style="font-family:""> the molecule and the co-directionality of them vectors </span><span style="font-family:""><i></span><b><i><span style="font-family:"">P</span></i></b><i><sub><span style="font-family:"">fp</span></sub></i><i><sub><span style="font-family:""></i></span></sub></i><span style="font-family:""> ferropolarization. The gravito-physical properties of the presented molecular structures in the composition of water make it possible to name them, respectively, as heavy and light clusters. 展开更多
关键词 Magnetic Charges True Antielectrons S-Gravitons Gravitational Field Ferro- and Paragravitation Gravitational Levitation Gravito-Chemical Bond Hydrocarbon and water Molecules heavy and Light the water Clusters
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Treatment of oilfield produced water by anaerobic process coupled with micro-electrolysis 被引量:24
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作者 Gang Li Shuhai Guo Fengmei Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第12期1875-1882,共8页
Treatment of oilfield produced water was investigated using an anaerobic process coupled with micro-electrolysis (ME), focusing on changes in chemical oxygen demand (COD) and biodegradability. Results showed that ... Treatment of oilfield produced water was investigated using an anaerobic process coupled with micro-electrolysis (ME), focusing on changes in chemical oxygen demand (COD) and biodegradability. Results showed that COD exhibited an abnormal change in the single anaerobic system in which it increased within the first 168 hr, but then decreased to 222 mg/L after 360 hr. The biological oxygen demand (five-day) (BOD5)/COD ratio of the water increased from 0.05 to 0.15. Hydrocarbons in the wastewater, such as pectin, degraded to small molecules during the hydrolytic acidification process. Comparatively, the effect of ME was also investigated. The COD underwent a slight decrease and the BOD5/COD ratio of the water improved from 0,05 to 0.17 after ME. Removal of COD was 38.3% under the idealized ME conditions (pH 6.0), using iron and active carbon (80 and 40 g/L, respectively). Coupling the anaerobic process with ME accelerated the COD removal ratio (average removal was 53.3%). Gas chromatography/mass spectrometry was used to analyze organic species conversion. This integrated system appeared to be a useful option for the treatment of water produced in oilfields. 展开更多
关键词 heavy oil produced water anaerobic system MICRO-ELECTROLYSIS BIODEGRADABILITY
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