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Soil Enzyme Activity Changes in Different-Aged Spruce Forests of the Eastern Qinghai-Tibetan Plateau 被引量:48
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作者 ZHANGYong-Mei ZHOUGuo-Yi +1 位作者 wuning BAOWei-Kai 《Pedosphere》 SCIE CAS CSCD 2004年第3期305-312,共8页
Activities of selected soil enzymes (invertase, acid phosphatase, proteinase,catalase, peroxidase and polyphenoloxi-dase) were determined under different spruce forests withrestoration histories of 5, 13, 18, 23, 27 y... Activities of selected soil enzymes (invertase, acid phosphatase, proteinase,catalase, peroxidase and polyphenoloxi-dase) were determined under different spruce forests withrestoration histories of 5, 13, 18, 23, 27 years and an old growth forest over 400 years old in theeastern Qinghai-Tibetan Plateau, China, and their possible use as indicators of ecosystems healthwere analyzed. Plots 10 X 10 m with 4 replications were established to investigate three hypotheses:soil enzyme activities a) would increase with the restoration process; b) would be greater insurface soils than at lower depths; and c) would be correlated to selected physicochemicalproperties. Results showed that as the forests developed after restoration, invertase and peroxidaseactivities usually increased up to the 23 year point. Also soil enzyme activities were associatedwith surface soils and decreased with depths, suggesting that in earlier restoration stages surfaceaddition of organic fertilizer to soils might be more effective than additions at depth. In the 0-20cm soil, there were significant correlations (P < 0.01 or < 0.05) between some soil enzymeactivities and some selected chemical properties. Therefore, temporal changes in enzyme activitiesshould be included as an indicator when evaluating sustainable forest management practices. 展开更多
关键词 acid phosphatase CATALASE INVERTASE PEROXIDASE spruce forest (picea spp.)
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Changes of Soil Enzyme Activities in Different Restoration Ages of Spruce Forests on the Eastern Qinghai-Tibet Plateau 被引量:3
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作者 ZHANGYong-mei BAOWei-kai +2 位作者 PANGXue-yong wuning ZHOUGuo-yi 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第4期701-706,共6页
Six soil enzymes (invertase, acid phosphatase, proteinase, catalase,peroxidase and polyphenoloxidase) were chosen for investigation under different spruce forests withrestoration ages of 4, 10, 16 years and an old-gro... Six soil enzymes (invertase, acid phosphatase, proteinase, catalase,peroxidase and polyphenoloxidase) were chosen for investigation under different spruce forests withrestoration ages of 4, 10, 16 years and an old-growth spruce forest over 400 yearsold in the easternQinghai-Tibet Plateau, China. Results showed that the activities of invertase, phosphatase,proteinase, catalase and peroxidase decreased in newly restored forests except forpholyphenoloxidase. With the development of forests after restoration, the activities of invertase,acid phosphadase, proteinase increased gradually. Our study also indicated that the soil enzymeactivities were associated with surface soils and decreased with depths. This result suggested thatin the earlier restoration stage the application of organic fertilizer may be more effective bysurface addition to soils than deep addition. 展开更多
关键词 acid phosphatase CATALASE INVERTASE peroxidase POLYPHENOLOXIDASE PROTEINASE spruce (Picea spp.) forest dynamics
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Gravitational Shielding Effect in Gauge Theory of Gravity 被引量:1
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作者 wuning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第4期567-572,共6页
In 1992,E.E.Podkletnov and R.Nieminen found that under certain conditions,ceramic superconductor with composite structure reveals weak shielding properties against gravitational force.In classical Newton's theory ... In 1992,E.E.Podkletnov and R.Nieminen found that under certain conditions,ceramic superconductor with composite structure reveals weak shielding properties against gravitational force.In classical Newton's theory of gravity and even in Einstein's general theory of gravity,there are no grounds of gravitational shielding effects.But in quantum gauge theory of gravity,the gravitational shielding effects can be explained in a simple and natural way.In quantum gauge theory of gravity,gravitational gauge interactions of complex scalar field can be formulated based on gauge principle.After spontaneous symmetry breaking,if the vacuum of the complex scalar field is not stable and uniform,there will be a mass term of gravitational gauge field.When gravitational gauge field propagates in this unstable vacuum of the complex scalar field,it will decays exponentially,which is the nature of gravitational shielding effects.The mechanism of gravitational shielding effects is studied in this paper,and some main properties of gravitational shielding effects are discussed. 展开更多
关键词 gravitational shielding effect symmetry breaking quantum gravity gauge field
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Unified Theory of Fundamental Interactions 被引量:1
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作者 wuning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第5期561-568,共8页
Based on local gauge invariance, four different kinds of fundamental interactions in nature are unified in a theory which has Gravitational Gauge Group gauge symmetry. In this approach, gravitational field, like elec... Based on local gauge invariance, four different kinds of fundamental interactions in nature are unified in a theory which has Gravitational Gauge Group gauge symmetry. In this approach, gravitational field, like electromagnetic field, intermediate gauge field, and gluon field, is represented by gauge potential. Four kinds of fundamental interactions are formulated in the similar manner, and therefore can be unified in a direct or semi-direct product group. The model discussed in this paper is a renormalizable quantum model and can be regarded as an extension of the standard model to gravitational interactions, so it can be used to study quantum effects of gravitational interactions. 展开更多
关键词 unified field theories gauge field quantum gravity
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基于回归分析的雷灾死亡人数预测模型 被引量:3
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作者 武宁 殷启元 +1 位作者 陈绿文 陈绍东 《气象与减灾研究》 2018年第3期231-235,共5页
利用1995—2016年广东省雷电灾害伤亡数据,对广东省雷电灾害中因雷击引起死亡的人数进行了统计分析。结果表明:1995—1998年为雷灾死亡人数的上升期,1998—2016年总体呈下降趋势,其中2004年雷灾死亡人数突增出现奇点。2008年前后雷灾死... 利用1995—2016年广东省雷电灾害伤亡数据,对广东省雷电灾害中因雷击引起死亡的人数进行了统计分析。结果表明:1995—1998年为雷灾死亡人数的上升期,1998—2016年总体呈下降趋势,其中2004年雷灾死亡人数突增出现奇点。2008年前后雷灾死亡人数变化明显,1995—2008年每年雷灾死亡人数波动较大,年平均死亡人数为66人;2009年后雷灾死亡人数波动平缓,年平均死亡人数为12人,同比减少了81.8%。对比分析五类拟合曲线后,得到广东省1998—2016年雷灾死亡人数年际动态变化预测模型的最佳拟合曲线是负指数曲线。为减少数据样本波动大和瞬间毛刺多的问题,通过百分位分析法,得到了2017年和2018年的预测值分别为11和10。t分布假设检验给出了2017年和2018年置信度为95%的预测区间上下限分别为24、6和25、6。 展开更多
关键词 雷电灾害 年际变化预测 回归分析 最佳拟合曲线 置信区间
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Relations Between Helicity Coupling Amplitude and L—S Coupling Amplitude 被引量:1
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作者 wuning RUANTu-Nan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第6期693-696,共4页
Relations between helicity coupling amplitude and L-S coupling amplitude are discussed. The equivalence condition for these two kinematic analysis methods and the limitations of the L-S coupling amplitude are also stu... Relations between helicity coupling amplitude and L-S coupling amplitude are discussed. The equivalence condition for these two kinematic analysis methods and the limitations of the L-S coupling amplitude are also studied in this paper. 展开更多
关键词 helicity coupling amplitude L-S coupling amplitude
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Gravitational Gauge Interactions of Scalar Field
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作者 wuning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第4X期429-434,共6页
Quantum gauge theory of gravity is formulated based on gauge principle. Because the Lagrangian has strict local gravitational gauge symmetry, gravitational gauge theory is a perturbatively renormalizable quantum theo... Quantum gauge theory of gravity is formulated based on gauge principle. Because the Lagrangian has strict local gravitational gauge symmetry, gravitational gauge theory is a perturbatively renormalizable quantum theory. Gravitational gauge interactions of scalar field are studied in this paper. In quantum gauge theory of gravity, scalar field minimal couples to gravitational field through gravitational gauge covariant derivative. Comparing the Lagrangian for scalar field in quantum gauge theory of gravity with the corresponding Lagrangian in quantum fields in curved space-time, the definition for metric in curved space-time in geometry picture of gravity can be obtained, which is expressed by gravitational gauge field. In classical level, the Lagrangian and Hamiltonian approaches are also discussed. 展开更多
关键词 量子万有引力 规范引力场 哈密顿趋近 拉格朗日趋近 广义相对论 标量场
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Geometric Formulation of Gauge Theory of Gravity
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作者 wuning ZHANGDa-Hua RUANTu-Nan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第3X期337-340,共4页
DitTerential geometric formulation of quantum gauge theory of gravity is studied in this paper. The quantum gauge theory of gravity is formulated completely in the framework of traditional quantum field theory. In ord... DitTerential geometric formulation of quantum gauge theory of gravity is studied in this paper. The quantum gauge theory of gravity is formulated completely in the framework of traditional quantum field theory. In order to study the relationship between quantum gauge theory of gravity and traditional quantum gravity which is formulated in curved space, it is important to set up the geometry picture of quantum gauge theory of gravity. The correspondence between quantum gauge theory of gravity and differential geometry is discussed and the geometry picture of quantum gauge theory of gravity is studied. 展开更多
关键词 量子引力 相对论 测量 几何学 爱因斯坦引力理论 时间-空间理论
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New Electroweak Model Without a Higgs Particle
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作者 wuning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第5期577-582,共6页
A new unified electroweak model is proposed in this paper. In this unified electroweak model, Higgsmechanism is not used, so no Higgs particle exists in the model. In order to keep the masses of intermediate gaugeboso... A new unified electroweak model is proposed in this paper. In this unified electroweak model, Higgsmechanism is not used, so no Higgs particle exists in the model. In order to keep the masses of intermediate gaugebosons non-zero, two sets of gauge fields will be introduced. In order to introduce symmetry breaking and to help tointroduce the masses of all fields, a vacuum potential is needed. Except for those terms concerning Higgs particle, thefundamental dynamical properties of this model are similar to those of the standard model. And in a proper limit, thismodel will approximately return to the standard model. The purpose of this paper is not to say that the Higgs particledoes not exist in Nature, it is only to prove that, without a Higgs particle, we can also set up a unified electroweak modelwhich is consistent with present experiments. 展开更多
关键词 electroweak interactions gauge symmetry Higgs particle symmetry breaking
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Supersymmetric U(1) Gauge Field Theory with Massive Gauge Field
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作者 wuning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第4期427-430,共4页
A new mechanism to introduce the mass of gauge field in supersymmetric gauge theory is discussed. The model has the strict local gauge symmetry and supersymmetry. Because we introduce two vector superfields simulta... A new mechanism to introduce the mass of gauge field in supersymmetric gauge theory is discussed. The model has the strict local gauge symmetry and supersymmetry. Because we introduce two vector superfields simultaneously, the model contains a massive gauge field as well as a massless gauge field. 展开更多
关键词 SUPERSYMMETRY gauge symmetry gauge field MASS
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Quantum Gauge General Relativity
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作者 wuning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第4X期543-552,共10页
Based on gauge principle, a new model on quantum gravity is proposed in the frame work of quantum gauge theory of gravity. The model has local gravitational gauge symmetry, and the field equation of the gravitational ... Based on gauge principle, a new model on quantum gravity is proposed in the frame work of quantum gauge theory of gravity. The model has local gravitational gauge symmetry, and the field equation of the gravitational gauge field is just the famous Einstein's field equation. Because of this reason, this model is called quantum gauge general relativity, which is the consistent unification of quantum theory and general relativity. The model proposed in this paper is a perturbatively renormalizable quantum gravity, which is one of the most important advantage of the quantum gauge general relativity proposed in this paper. Another important advantage of the quantum gauge general relativity is that it can explain both classical tests of gravity and quantum effects of gravitational interactions, such as gravitational phase effects found in COW experiments and gravitational shielding effects found in Podkletnov experiments. 展开更多
关键词 标准场 量子重力 广义相对论 重正化
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Solution to the Cosmological Constant Problem by Gauge Theory of Gravity
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作者 wuning GermanoResconi +3 位作者 ZHENGZhi-Peng XUZhan ZHANGDa-Hua RIJANTu-Nan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第2X期253-256,共4页
Based on geometry picture of gravitational gauge theory, the cosmological constant is determined theoreti-cally. The cosmological constant is related to the average energy density of gravitational gauge field. Because... Based on geometry picture of gravitational gauge theory, the cosmological constant is determined theoreti-cally. The cosmological constant is related to the average energy density of gravitational gauge field. Because the energy density of gravltatlona] gauge field is negative, the cosmological constant is positive, which generates repulasive force on stars to make the expansion rate of the Universe accelerated. A rough estimation of it gives out its magnitude of the order of about 10^52m^-2, which is well consistent with experimental results. 展开更多
关键词 宇宙学常量 宇宙论 量子引力 广义相对论
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Search for Exotic States in J/ψ→ρηπ
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作者 wuning RUANTu-Nan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第3期309-314,共6页
It is an ideal place to search for exotic states through J/ψ hadronic decays.In this paper,we discuss the way to use the partial wave analysis (PWA) based on covariant helicity amplitude analysis to study the invaria... It is an ideal place to search for exotic states through J/ψ hadronic decays.In this paper,we discuss the way to use the partial wave analysis (PWA) based on covariant helicity amplitude analysis to study the invariant mass spectrum of ηπ and to find the evidence of the existence of exotic states in this channel.The formula for PWA is also given.It is the theoretical foundation of experimental physics analysis on exotic states searching in J/ψ hadronic decays.The theoretical formula can also be used in physics analysis of J/ψ decays into ωππ,φππ,ωKK,φKK and K^* (892)Kπ. 展开更多
关键词 量子色动力学 外来态 J/ψ→ρηπ 强子衰变
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Unification of Electromagnetic Interactions and Gravitational Interactions
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作者 wuning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第3期322-326,共5页
Unified theory of gravitational interactions and electromagnetic interactions is discussed in this paper.Based on gauge principle, electromagnetic interactions and gravitational interactions are formulated in the same... Unified theory of gravitational interactions and electromagnetic interactions is discussed in this paper.Based on gauge principle, electromagnetic interactions and gravitational interactions are formulated in the same mannerand are unified in a semi-direct product group of U(1) Abelian gauge group and gravitational gauge group. 展开更多
关键词 quantum gravity unified field theory gauge field theory
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Gravitational Gauge Interactions of Dirac Field
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作者 wuning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期381-384,共4页
Gravitational interactions of Dirac field are studied in this paper. Based on gauge principle, quantum gauge theory of gravity, which is perturbatively renormalizable, is formulated in the Minkowski space-time. In qua... Gravitational interactions of Dirac field are studied in this paper. Based on gauge principle, quantum gauge theory of gravity, which is perturbatively renormalizable, is formulated in the Minkowski space-time. In quantum gauge theory of gravity, gravity is treated as a kind of fundamental interactions, which is transmitted by gravitational gauge field, and Dirac field couples to gravitational field through gravitational gauge covariant derivative. Based on this theory, we can easily explain gravitational phase effect, which has already been detected by COW experiment. 展开更多
关键词 quantum gravity gauge field Dirac field
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Gauge Model with massive Gravitons
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作者 wuning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第6期671-674,共4页
Gauge theory of gravity is formulated based on principle of local gauge invariance. Because the model hasstrict local gravitational gauge symmetry, and gauge theory of gravity is a perturbatively renormalizable quantu... Gauge theory of gravity is formulated based on principle of local gauge invariance. Because the model hasstrict local gravitational gauge symmetry, and gauge theory of gravity is a perturbatively renormalizable quantum model.However, in the original model, all gauge gravitons are massless. We want to ask whether there exist massive gravitonsin Nature. In this paper, we will propose a gauge model with massive gravitons. The mass term of gravitational gaugefield is introduced into the theory without violating the strict local gravitational gauge symmetry. Massive gravitons canbe considered to be possible origin of dark energy and dark matter in the Universe. 展开更多
关键词 gauge field quantum gravity dark matter and dark energy
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New Mechanism for Mass Generation of Gauge Field
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作者 wuning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第2期169-172,共4页
A new mechanism for mass generation of gauge field is discussed in this paper. By introducing two sets of gauge fields and making the variations of these two sets of gauge fields compensated each other under local gau... A new mechanism for mass generation of gauge field is discussed in this paper. By introducing two sets of gauge fields and making the variations of these two sets of gauge fields compensated each other under local gauge transformations, the mass term of gauge fields is introduced into the Lagrangian without violating the local gauge symmetry of the Lagrangian. This model is a renormalizable quantum model. 展开更多
关键词 mass of gauge field gauge symmetry gauge field
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Covariant Helicity Amplitude Analysis for J/ψ→γPP
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作者 wuning RUANTu-Nan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第5期547-552,共6页
Covariant helicity amplitude analysis for the process of J/ψ →γPP is discussed.Starting from the S- matrix elements of decay process,we deduce the formulae of helicity coupling amplitudes for two-body decay process... Covariant helicity amplitude analysis for the process of J/ψ →γPP is discussed.Starting from the S- matrix elements of decay process,we deduce the formulae of helicity coupling amplitudes for two-body decay process. These formulae are used to analyze intermediate resonance states in the process of J/ψ decay to γππ,γKK,γηη' etc. 展开更多
关键词 QCD J/ψ→γPP反应 协变手征振幅
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Cosmological Model Based on Gauge Theory of Gravity
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作者 wuning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期957-960,共4页
A cosmological model based on gauge theory of gravity is proposed in thispaper. Combining cosmological principle and field equation of gravitational gauge field, dynamicalequations of the scale factor R(t) of our univ... A cosmological model based on gauge theory of gravity is proposed in thispaper. Combining cosmological principle and field equation of gravitational gauge field, dynamicalequations of the scale factor R(t) of our universe can be obtained. This set of equations has threedifferent solutions. A prediction of the present model is that, if the energy density of theuniverse is not zero and the universe is expanding, the universe must be space-fiat, the totalenergy density must be the critical density ρ_c of the universe. For space-Bat case, this modelgives the same solution as that of the Friedmann model. In other words, though they have differentdynamics of gravitational interactions, general relativity and gauge theory of gravity give the samecosmological model. 展开更多
关键词 COSMOLOGY quantum gravity
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