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定干高度与时间对直干桉嫩枝数量和质量的影响
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作者 唐有慈 李妹 +2 位作者 张兴才 曹子林 王晓丽 《中南林业科技大学学报》 CAS CSCD 北大核心 2024年第7期47-53,共7页
【目的】为构建直干桉促萌技术体系提供理论依据,研究定干高度和定干时间对直干桉苗木萌蘖嫩枝的影响。【方法】以1年直干桉实生苗为试材,采用2因素(定干高度:5、10、15、20 cm;定干时间:9、10、11月)全面试验设计进行定干高度与定干时... 【目的】为构建直干桉促萌技术体系提供理论依据,研究定干高度和定干时间对直干桉苗木萌蘖嫩枝的影响。【方法】以1年直干桉实生苗为试材,采用2因素(定干高度:5、10、15、20 cm;定干时间:9、10、11月)全面试验设计进行定干高度与定干时间对直干桉萌蘖嫩枝数量、有效嫩枝数量、有效嫩枝长度和有效嫩枝基径效应影响的研究,分析最佳定干高度和定干时间。【结果】定干处理后60与120 d,萌蘖产生的嫩枝数量(4.68,3.72,0.30枝·株^(-1)),有效嫩枝数(3.25,3.38枝·株^(-1)),有效嫩枝长度(8.639,9.878 cm),有效嫩枝基径(0.748,1.217 mm)效果最好的均为处理组合A_(4)B_(1)(定干高度20 cm,定干时间9月)。60 d与120 d 12个处理组合间的嫩枝数、有效嫩枝数、有效嫩枝长度、有效嫩枝基径均具有极显著差异,总体上处理组合A_(4)B_(1)显著大于其余处理组合;因素水平间均存在极显著差异,A因素均是影响苗木的主要因子,总体上A_(4)极显著大于其他3个水平,B_(1)极显著大于其他2个水平,理论优水平组合为A_(4)B_(1)。【结论】综上,定干高度与定干时间对直干桉苗木萌蘖能力影响极其显著,利于直干桉苗木促萌的最优处理组合为A_(4)B_(1)(定干高度20 cm,定干时间9月),定干高度是影响苗木萌蘖的主要因子,在实际生产中可根据试验结果采取最适定干高度与定干时间。 展开更多
关键词 直干桉 定干高度 定干时间 嫩枝数量 嫩枝质量
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Coherent States of Nonlinear Oscillators with Position-Dependent Mass:Temporal Stability and Fractional Revivals 被引量:1
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作者 Naila Amir Shahid Iqbal 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第8期181-190,共10页
We develop generalized coherent states for a class of nonlinear oscillators with position-dependent effective mass in the context of the Gazeau–Klauder formalism and discuss some of their properties. In order to inve... We develop generalized coherent states for a class of nonlinear oscillators with position-dependent effective mass in the context of the Gazeau–Klauder formalism and discuss some of their properties. In order to investigate the temporal evolution we first explore the statistical properties by means of weighting distribution and the Mandel parameter. It is found that the temporal evolution of the coherent states may exhibit the phenomena of quantum revivals and fractional revivals for a particular choice of position-dependent mass oscillator. 展开更多
关键词 position-dependent effective mass nonlinear oscillators Gazeau-Klauder coherent states Mandelparameter sub-Poissonian statistics temporal stability quantum revivals fractional revivals
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L_2 DISTURBANCE ATTENUATION FOR A CLASS OF TIME-DELAY HAMILTONIAN SYSTEMS 被引量:4
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作者 Weiwei SUN Yuzhen WANG Renming YANG 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2011年第4期672-682,共11页
This paper considers the problem of L2-disturbance attenuation for a class of time-delay port-controlled Hamiltonian systems. A v-dissipative inequality is established by using a proper control law and a storage funct... This paper considers the problem of L2-disturbance attenuation for a class of time-delay port-controlled Hamiltonian systems. A v-dissipative inequality is established by using a proper control law and a storage function. Then based on the Razumikhin stability theorem, a sufficient condition is proposed for the asymptotically stability of the closed-loop system. Finally, the authors investigate the case that there are time-invariant uncertainties belonging to some convex bounded polytypic domain and an L2 disturbance attenuation control law is proposed. Study of illustrative example with simulation shows that the presented method in this paper works very well in the disturbance attenuation of time-delay Hamiltonian systems. 展开更多
关键词 Hamiltonian systems L2 disturbance attenuation STABILITY time-delay.
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Inflation in Non-de Sitter Background with Coherent States
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作者 E.Yusofi M.Mohsenzadeh M.R.Tanhayi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第3期308-314,共7页
We use the excited coherent states built over the initial non-de Sitter modes,to study the modification of spectra of primordial scalar fluctuation.Non-de Sitter modes are actually the asymptotic solution of the infla... We use the excited coherent states built over the initial non-de Sitter modes,to study the modification of spectra of primordial scalar fluctuation.Non-de Sitter modes are actually the asymptotic solution of the inflaton field equation[J.High Energy Phys.09(2014) 020].We build excited coherent states over the non-de Sitter modes and despite the Jack of interactions in the Lagrangian,we find a non-zero one-point function.It is shown that the primordial non-Gaussianity resulting from excited-de Sitter modes depend both of time and background space-time.It is very tiny of order(≤10^-24),at the Planck initial fixed time that confirmed by resent observations for single field inflation but it grows in the present epoch.Moreover,our results at the leading order are similar to what obtained with general initial states and in the dS limit leads to standard results[J.Cosmol.Astropart.Phys.1202(2012) 005].We will show that the non-dS modes and its resulting spectrum are more usable for far past time limit. 展开更多
关键词 INFLATION initial states planck time background space-time
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