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Origin and Distribution of Groundwater Chemical Fields of the Oilfield in the Songliao Basin,NE China 被引量:8
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作者 JIN Aimin LOU Zhanghua +2 位作者 ZHU Rong CAI Xiyuan GAO Ruiqi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第5期688-696,共9页
There are many factors affecting the chemical characteristics of groundwater in the forming process of groundwater chemical fields, such as freshening due to meteoric water leaching downwards, freshening due to mudsto... There are many factors affecting the chemical characteristics of groundwater in the forming process of groundwater chemical fields, such as freshening due to meteoric water leaching downwards, freshening due to mudstone compaction and water release, concentration due to infiltration and freshening due to dehydration of clay minerals. As a result, the groundwater chemical fields are characterized by lengthwise stages and planar selectivity. The former arouses vertical chemical zonality of groundwater. Five units could be identified downwards in the Songliao basin: (1) freshening zone due to downward-leaching meteoric water, (2) concentration zone due to evaporation near the ground surface, (3) freshening zone due to mudstone compaction and water release, and concentration zone due to compaction and infiltration, (4) freshening zone due to dehydration of clay minerals, and (5) filtration-concentration zone; whereas the latter determines the planar division of groundwater chemical fields: (1) the freshening area due to meteoric water, asymmetrically on the margin of the basin, (2) the freshening area due to mudstone compaction and water release in the central part of the basin, (3) the leaky area, which is a transitional zone, and (4) leakage-evaporation area, which is a concentration zone. In the direction of centrifugal flows caused by mudstone compaction in the depression area, the mineralization degree, concentrations of Na^+ and Cl^-, and salinity coefficient (SC) increase, while concentrations of (CO3^2- +HCO3^-) and SO4^2-, metamorphism coefficient (MC) and desulfuration coefficient (DSC) decrease. However, all these parameters increase in the direction of gravity-induced centripetal flows. 展开更多
关键词 Songliao Basin hydrodynamic field groundwater chemical field vertical zonality planar division
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Chemical Weeding in Dry Direct Seeding Fields of Single Cropping Middlelate Rice
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作者 Liu Huaizhen Li Kanghuo +5 位作者 Huang Qing Lu Xiuming Zhang Bin Li Huifen Zou Jixiang Zhou Shaochuan 《Plant Diseases and Pests》 CAS 2014年第3期34-38,共5页
Chemical weeding in dry direct seeding fields of single cropping middle-late rice was studied in Huida vegetable farm of Huizhou City in 2012. The main treatment was herbicide( pretilachlor + bensulfuron-methyl,Yang... Chemical weeding in dry direct seeding fields of single cropping middle-late rice was studied in Huida vegetable farm of Huizhou City in 2012. The main treatment was herbicide( pretilachlor + bensulfuron-methyl,Yangguo and butachlor),and the sub-treatment was application method( soil treatments,seedling treatment and integrated treatment). The results showed that 80 g pretilachlor + bensulfuron-methyl( 36% pretilachlor + 4% bensulfuron-methyl) diluted with 50 kg water could be sprayed or 200 g Yangguo( 23. 9% butachlor + 1. 1% bensulfuron-methyl) mixed with 15 kg sandy soil could be broadcasted per 667 m2 on the sowing day or the second day under moist condition of soil,which could effectively control weeds in dry direct seeding fields of single cropping middle-late rice. 展开更多
关键词 Single cropping middle-late rice Dry direct seeding field chemical weeding
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A Dynamical Approach to the Explanation of the Upper Critical Field Data of Compressed H3S
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作者 Gulshan Malik Vijaya S. Varma 《World Journal of Condensed Matter Physics》 2023年第3期79-89,共11页
Excellent fits were obtained by Talantsev (MPLB 33, 1950195, 2019) to the temperature (T)-dependent upper critical field (H<sub>c</sub><sub>2</sub>(T)) data of H<sub>3</sub>S report... Excellent fits were obtained by Talantsev (MPLB 33, 1950195, 2019) to the temperature (T)-dependent upper critical field (H<sub>c</sub><sub>2</sub>(T)) data of H<sub>3</sub>S reported by Mozaffari et al. [Nature Communications 10, 2522 (2019)] by employing four alternative phenomenological models, each of which invoked two or more properties from its sample-specific set S<sub>1</sub> = {T<sub>c</sub>, gap, coherence length, penetration depth, jump in sp.ht.} and a single value of the effective mass (m*) of an electron. Based on the premise that the variation of H<sub>c</sub><sub>2</sub>(T) is due to the variation of the chemical potential μ(T), we report here fits to the same data by employing a T-, μ- and m*-dependent equation for H<sub>c</sub><sub>2</sub>(T) and three models of μ(T), viz. the linear, the parabolic and the concave-upward model. For temperatures up to which the data are available, each of these provides a good fit. However, for lower values of T, their predictions differ. Notably, the predicted values of H<sub>c</sub><sub>2</sub>(0) are much higher than in any of the models dealt with by Talantsev. In sum, we show here that the addressed data are explicable in a framework comprising the set S<sub>2</sub> = {μ, m*, interaction parameter λ<sub>m</sub>, Landau index N<sub>L</sub>}, which is altogether different from S<sub>1</sub>. 展开更多
关键词 Compressed H2S Upper Critical Magnetic field Pairing Equation Incorporating Temperature chemical Potential and Magnetic field Temperature Dependence of the chemical Potential
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An easy way to controllably synthesize one-dimensional Sm B_6 topological insulator nanostructures and exploration of their field emission applications 被引量:2
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作者 杨汛 甘海波 +6 位作者 田颜 许宁生 邓少芝 陈军 陈焕君 梁世东 刘飞 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第11期503-509,共7页
A convenient fabrication technique for samarium hexaboride(SmB6) nanostructures(nanowires and nanopencils) is developed, combining magnetron-sputtering and chemical vapor deposition. Both nanostructures are proven... A convenient fabrication technique for samarium hexaboride(SmB6) nanostructures(nanowires and nanopencils) is developed, combining magnetron-sputtering and chemical vapor deposition. Both nanostructures are proven to be single crystals with cubic structure, and they both grow along the [001] direction. Formation of both nanostructures is attributed to the vapor-liquid-solid(VLS) mechanism, and the content of boron vapor is proposed to be the reason for their different morphologies at various evaporation distances. Field emission(FE) measurements show that the maximum current density of both the as-grown nanowires and nanopencils can be several hundred μA/cm^2, and their FN plots deviate only slightly from a straight line. Moreover, we prefer the generalized Schottky-Nordheim(SN) model to comprehend the difference in FE properties between the nanowires and nanopencils. The results reveal that the nonlinearity of FN plots is attributable to the effect of image potential on the FE process, which is almost independent of the morphology of the nanostructures.All the research results suggest that the SmB6 nanostructures would have a more promising future in the FE area if their surface oxide layer was eliminated in advance. 展开更多
关键词 one-dimensional SmB6 nanostructures chemical vapor deposition(CVD) field emission(FE) image potential
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Radiofrequency field enhanced chemical ionization with vacuum ultraviolet lamp for miniature time-of-flight mass spectrometer 被引量:1
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作者 Lijuan Zhou Jichun Jiang +5 位作者 Kun Zhao Jinxu Li Chenxin Wu Haiyang Li Di Tian Keyong Hou 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第5期707-710,共4页
It is difficult to rapidly and on-line detect trace volatile organic compounds for miniature massspectrometry due to its limited sampling volume at slow pumping speed. In this paper, we developed anew radiofrequency f... It is difficult to rapidly and on-line detect trace volatile organic compounds for miniature massspectrometry due to its limited sampling volume at slow pumping speed. In this paper, we developed anew radiofrequency field enhanced chemical ionization source (RF-ECI) with vacuum ultraviolet (VUV)lamp by coupling radiofrequency electric field and direct-current field together. The experiment resultsshowed that the sensitivity of benzene, toluene, hydrogen sulfide and other compounds increased by 2-3orders of magnitude under the introduction of RF-ECI comparing to traditional single photon ionization(SPI). At the same time, the reagent ion of O2+ realized the charge transfer reaction chemical ionization,and the RF-ECI effectively expanded the detection range of the VUV lamp based SPI. The VUV lamp hasinherent advantages in the on-site analytical instrument for its small size and low power consumption,and the VUV lamp based RF-ECI miniature time-of-flight mass spectrometer (TOFMS) has a limit-of-detection for H2S as low as 0.0571 mg/m3, and it is expected to be used widely in the field of on-site rapidanalvsis. 展开更多
关键词 Radio-frequency field enhanced chemical ionization Vacuum ultraviolet lamp Single photon ionization Miniature time-of-flight mass spectrometer On site analysis
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Motoyosi Sugita—A “Widely Unknown” Japanese Thermodynamicist Who Explored the 4th Law of Thermodynamics for Creation of the Theory of Life
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作者 Kazumoto Iguchi 《Open Journal of Biophysics》 2016年第4期125-232,共109页
The purpose of this paper is to introduce to you, the Western people, nowadays a “widely unknown” Japanese thermodynamicist by the name of Motoyosi Sugita and his study on the thermodynamics of transient phenomena a... The purpose of this paper is to introduce to you, the Western people, nowadays a “widely unknown” Japanese thermodynamicist by the name of Motoyosi Sugita and his study on the thermodynamics of transient phenomena and his theory of life. This is because although he was one of the top theoretical physicists in Japan before, during and after WWII and after WWII he promoted the establishment of the biophysical society of Japan as one of the founding members, he himself and his studies themselves have seemed to be totally forgotten nowadays in spite that his study was absolutely important for the study of life. Therefore, in this paper I would like to present what kind of person he was and what he studied in physics as a review on the physics work of Motoyosi Sugita for the first time. I will follow his past studies to introduce his ideas in theoretical physics as well as in biophysics as follows: He proposed the bright ideas such as the quasi-static change in the broad sense, the virtual heat, and the field of chemical potential etc. in order to establish his own theory of thermodynamics of transient phenomena, as the generalization of the Onsager-Prigogine’s theory of the irreversible processes. By the concept of the field of chemical potential that acquired the nonlinear transport, he was seemingly successful to exceed and go beyond the scope of Onsager and Prigogine. Once he established his thermodynamics, he explored the existence of the 4th law of thermodynamics for the foundation of theory of life. He applied it to broad categories of transient phenomena including life and life being such as the theory of metabolism. He regarded the 4th law of thermodynamics as the maximum principle in transient phenomena. He tried to prove it all life long. Since I have recently found that his maximum principle can be included in more general maximum principle, which was known as the Pontryagin’s maximum principle in the theory of optimal control, I would like to explain such theories produced by Motoyosi Sugita as detailed as possible. And also I have put short history of Motoyosi Sugita’s personal life in order for you to know him well. I hope that this article helps you to know this wonderful man and understand what he did in the past, which was totally forgotten in the world and even in Japan. 展开更多
关键词 Unknown Japanese Thermodynamicist Motoyosi Sugita Thermodynamics of Transient Phenomena Virtual Heat Broad Quasi-Static Change chemical Potential field of chemical Potential Diffusion Phenomena Number of Partition Dissipation Function Onsager’s Theory of Irreversible Processes Prigogine’s Least Production of Entropy 4th Law of Thermodynamics Maximum Principle Pontryagin’s Maximum Principle Bellman’s Optimality Principle Theory of Metabolism Theory of Life CYBERNETICS
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Growth of Single-crystalline Transition Metal Dichalcogenides Monolayers with Large-size
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作者 ZHOU Shcngxuc JIAO Liying 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2020年第4期511-517,共7页
Two-dimensional(2D)transition metal dichalcogenides(TMDCs)semiconductors,such as monolayers of molybdenum disulfide(MoS2)and tungsten disulfide(WS2)can potentially serve as ultrathin channel materials for building sho... Two-dimensional(2D)transition metal dichalcogenides(TMDCs)semiconductors,such as monolayers of molybdenum disulfide(MoS2)and tungsten disulfide(WS2)can potentially serve as ultrathin channel materials for building short channel field-eflect transistors(FETs)to further extend Moore's Law.It is essential to develop controllable approaches for the syntliesis of large single crystals of these 2D semiconductors to promote their practical applications in future electronics.In this short review,we summarized the recent advances on the chemical vapor deposition(CVD)of single crystalline semiconducting 2D TMDCs with a large size.We first discussed the driving force and urgent demands on developing controllable approaches for the growth oflarge 2D TMDCs single crystals and then summarized the current strategies and representative studies on the CVD growth of large 2D single crystals.Finally,we discussed the challenges and future directions in this topic. 展开更多
关键词 Two dimensional Single crystal chemical vapor deposition field effect transistor
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Survival of charged ρ condensation at high temperature and density
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作者 刘好 余浪 黄梅 《Chinese Physics C》 SCIE CAS CSCD 2016年第2期12-18,共7页
The charged vector ρ mesons in the presence of external magnetic fields at finite temperature T and chemical potential μ have been investigated in the framework of the Nambu-Jona-Lasinio model.We compute the masses ... The charged vector ρ mesons in the presence of external magnetic fields at finite temperature T and chemical potential μ have been investigated in the framework of the Nambu-Jona-Lasinio model.We compute the masses of charged ρ mesons numerically as a function of the magnetic field for different values of temperature and chemical potential.The self-energy of the ρ meson contains the quark-loop contribution,i.e.the leading order contribution in 1/NC expansion.The charged ρ meson mass decreases with the magnetic field and drops to zero at a critical magnetic field eBc,which indicates that the charged vector meson condensation,i.e.the electromagnetic superconductor can be induced above the critical magnetic field.Surprisingly,it is found that the charged ρ condensation can even survive at high temperature and density.At zero temperature,the critical magnetic field just increases slightly with the chemical potential,which indicates that charged ρ condensation might occur inside compact stars.At zero density,in the temperature range 0.2 — 0.5 GeV,the critical magnetic field for charged ρ condensation is in the range of 0.2 — 0.6 GeV^2,which indicates that a high temperature electromagnetic superconductor might be created at LHC. 展开更多
关键词 magnetic field charged ρ condensation temperature chemical potential
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