检索结果-南通市图书馆

维普期刊数据库

Stable Oxygen and deuterium Isotope Techniques to Identify Plant Water Sources

在线全文

学校读者我要写书评

暂无评论

Journal of Water Resource and Protection 2014年第15期6卷 1501-1508页

作者： M. Edwin S. Lubis I. Yani Harahap Taufiq C. Hidayat Y. Pangaribuan Edy S. Sutarta Zaharah A. Rahman Christopher Teh M. M. Hanafi Indonesia Oil Palm Research Institute Medan Indonesia Universiti Putra Malaysia Serdang Malaysia

There is still very little information on the sources of water absorbed by oil palm plant. This information is very important for water management system in oil palm plantation. Thus, this study was carried out to determine current water sources absorbed by the oil palm roots using oxygen (δ18O) and deuterium isotopes (δD) techniques. Sketches of oxygen and deuterium isotope were total rainfall, throughfall, runoff, measurement at 5 soil depths (namely: 20 cm, 50 cm, 100 cm, 150 cm, and 200 cm), and oil palm stem. Results of this study showed huge variance in the values of oxygen and deuterium isotope. Based on Least Significant Difference (LSD) test, there was no significant value in the oxygen and deuterium isotope of stem water and others;however, a similar value was obtained at the depths of 0 - 20 cm and 20 - 50 cm with the stem water. This indicated that oil palm absorbed water from 0 - 50 cm depth. This result agreed with the oil palm rooting system, which has verified that the root quarter is the most active root of oil palm.

关键词： deuterium Isotope Technique Plant Water Sources Stable Oxygen

History and General Characteristics of the Adaptive Control System of the deuterium Pre-concentration Stage in Heavy Water Production

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Mathematics and System Science 2019年第1期9卷 7-20页

作者： Karachenets Dmitryi St. Derevlyanskaya 19a of.54 Kyiv 04119 Ukraine

The history of creation in 1971–1975 years at SDB MMS of the Institute of Cybernetics (Kyiv city) the control system for the deuterium pre-concentration stage in heavy water production at Dneprodzerzhinsk chemical plant (now Kamianske city, PJSC “DneprAzot”) is considered. It is given a technological block-diagram of the stage with its components and block-diagram of ACSTP which was developed in consequence of investigations of this complex managed object. A mathematical model of the distillation columns in the separating units of hydrogen isotopes which was used for synthesis of an algorithm of the adaptive stochastic optimal system with active accumulation of information about managed probabilistic processes is described. The results of the carried out tests of the system confirmed its efficiency.

关键词： Adaptive control system deuterium heavy water distillation ACSTP mathematical model managed probabilistic process

Electrochemical Reduction of Benzo[b]thiophene 1,1-Dioxides with HFIP as Hydrogen Donor

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第6期42卷 585-591页

作者： Ming-Zhong Guo Mei-Jin Mou Zhuo Chen Shao-Fei Ni Ming Li Li-Rong Wen Lin-Bao Zhang State Key Laboratory Base of Eco-Chemical Engineering College of Chemistry and Molecular EngineeringQingdao University of Science & TechnologyQingdaoShandong266042 China Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province Shantou UniversityShantouGuangdong515063 China

A straightforward electrochemical reduction of benzo[b]thiophene 1,1-dioxides with HFIP as the hydrogen donor has been reported in an undivided cell under metal-free ***,the tolerance of various functional groups and ... 详细信息

关键词： Electrochemistry Reduction Benzo[b]thiophene 1,1-dioxides deuterium Hydrogen source

Recent Advances in Deuteration Reactions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第10期42卷 1145-1156页

作者： Hao Li Muhammad Shabbir Wu Li Aiwen Lei Institutefor Advanced Studies(IAS) Collegeof Chemistry and Molecular SciencesWuhan UniversityWuhanHubei 430072China

The deuteration of organic compounds has attracted more attentions in recent years for the potential applications in new drug discovery and synthetic *** this purpose,many efficient deuterium labeling methodologies have been developed,including hydrogen isotope exchange(HIE),reductive deuteration,and dehalogenative deuteration that allow for the synthesis of selectively deuterated *** the last few years,great breakthroughs in selective isotope labeling have been achieved and the interest in new methodologies for the deuteration of organic molecules is *** this review,we summarized the recent developments in the selective deuteration of organic molecules since *** types of key processes in deuterium incorporation reactions,including H/D exchange,reductive deuteration and dehalogenative deuteration,are introduced and discussed.

关键词： Deuterated compounds H/D exchange Reductive deuterations Dehalogenative deuterations deuterium C-Hactivation Synthetic methods

Mass Increase with Strong and Gravitational Potentials, and Mass Defect with Electromagnetic Potential

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of High Energy Physics, Gravitation and Cosmology 2024年第3期10卷 1079-1094页

作者： Hany Ali Hussein Electronic & Communication Shoubra College University of Banha Banha Egypt

The proposal is “mass increases due to strong and gravitational potentials, while it decreases due to Electromagnetic potential”. This proposal explains the big difference in mass between hadrons (protons, neutrons, & mesons) and their components (quarks), mass difference between nucleus and its individual components (protons and neutrons), massless of gamma photons, abnormal masses of mesons and bosons, and the excess in galaxy masses (dark matter). Also, this proposal shows the exact relation between mass and energy: Strong Potential=−3.04mc2| Electric Potential |=−5.57×10−3mc2Gravitational Potential=−1.22×10−7mc2where m represents the excess in mass due to strong potential, or gravitational potential and represents the decrease in mass due to electromagnetic potential. Released energy here equals potential energy and doesn’t equal decrease in mass using the formula E = mc2. Released energy is transferred to heat, photons, kinetic energy… Finally, proposal will try to describe the relation between photon energy and mass of its components using the general equation of kinetic energy: Photon Energy=1/2mc2m is the sum of the individual masses of its components, while the total mass of photon is zero.

关键词： Mass Defect Dark Matter Photon Gamma Photon Strong Potential Gravitational Potential Electromagnetic Potential Quarks Mesons Bosons deuterium Proton Neutron

美国《保健物理》(Health Physics)杂志英文摘要(2023年126卷第3期)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

辐射防护 2024年第3期44卷 315-317页

Health ***,Volume 126,Number 3Evaluation of deuterium Oxide Deposition Velocity over a Forest Environment Brian ***1,Ashlee Swindle1,Lucas Angelette1,Candace ***2,Wendy ***1(*** River National Laboratory,203 Laurens St SW,Aiken,SC 29802;*** Oncology,Lilly Corporate Center,Indianapolis,IN 46285(formerly at Savannah River National Laboratory,203 Laurens St SW,Aiken,SC 29802)).

关键词：英文摘要 deuterium

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国西部降水中/D及相关气候研究(英文)

冰川冻土 1999年第4期 357-361页

作者：田立德姚檀栋

The spatial variation of δD in precipitation in West China is discussed in this paper, and the relationship between δD in precipitation and temperature is analyzed as well based on the measured δD in precipitation samples collected in 6 sites in West China during mainly the summer of 1996. δD in precipitation in West China shows an intensive spatial variation: lower in the south of the Tibetan Plateau and higher in the north of West China. Analysis shows that the low value of δD is caused by obvious impact of southwest monsoon, and a very high value is due to the regional water cycle in the arid regions. δD in precipitation in the interior of the continent shows a strong “temperature effect”, while not in the south of the Tibetan Plateau.

关键词： deuterium precipitation West China

The steady-state and dynamic simulation of cascade distillation system for the production of oxygen-18 isotope from water

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2016年第8期24卷 979-988页

作者： Yunhu Gao Zhihong Xu Kejing Wu Xiaolu Wang Zhaojun Yu Weiyang Fei Jiangsu Huayi Technology Co. Ltd. State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University China Construction Installation Engineering Co.Ltd

Accurate simulation of water distillation system for oxygen-18(18O) isotope separation is necessary to guide industrial practice, since both deuterium(D) and oxygen-18 isotope get enriched and interfere with each other. In the present work, steady-state and dynamic distillation models are established based on a classic method and a cascade distillation system with 5 towers is introduced to test the models. The theoretical expressions of separation factor αH/Dfor protium/deuterium and separation factor α^(16)O/^(18) *** oxygen-16/oxygen-18 were derived,with the existence of deuterium and oxygen-18, respectively. The results of the steady-state simulation by the classical method proposed in the present work agreed well with the results of the lumping method. The dynamic process could be divided into 5 stages. Impressively, a peak value of product withdraw was observed before the final steady state, which was resulted from the change of ^(16)O/^(18) O separation factor and isotope distribution. An interesting low concentration zone in the towers of T2–T5 existed at the beginning of the dynamic process and it required industrial evidence.

关键词： Oxygen-18 deuterium Steady-state simulation Dynamic simulation Isotope separation

维普期刊数据库

Analysis of the Zeeman effect on Dαspectra on the EAST tokamak

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2017年第4期26卷 276-282页

作者：高伟黄娟吴承瑞许棕侯玉梅金钊陈颖杰张鹏飞张凌吴振伟 EAST Team Institute of Plasma Physics Chinese Academy of SciencesHefei 230031China

Based on the passive spectroscopy,the D_α atomic emission spectra in the boundary region of the plasma have been measured by a high resolution optical spectroscopic multichannel analysis（OSMA） system in EAST *** Zeeman splitting of the D_α spectral lines has been observed.A fitting procedure by using a nonlinear least squares method was applied to fit and analyze all polarization π and ±σ components of the D_α atomic spectra to acquire the information of the local *** spectral line shape was investigated according to emission spectra from different regions（e.g.,low-field side and high-field side） along the viewing *** polarization component was fitted and classified into three energy categories（the cold,warm,and hot components） based on different atomic production processes,in consistent with the transition energy distribution by calculating the gradient of the D_α spectral *** emission position,magnetic field intensity,and flow velocity of a deuterium atom were also discussed in the context.

关键词： Zeeman effect plasma spectrum deuterium

维普期刊数据库