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Effects of plug tray cell size on the growth of Atractylodes Chinensis (DC) Koidz seedlings

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International Journal of Agricultural and Biological Engineering 2024年第4期17卷 45-52页

作者： Kaixuan shi Juwen Liang Fang Ji Dongxian He Key Laboratory of Agricultural Engineering in Structure and Environment of MARA College of Water Resources&Civil EngineeringChina Agricultural UniversityBeijing 100083China

Atractylodes Chinensis(DC)Koidz is a perennial herb often used as a prescription medicine for influenza,to invigorate the spleen and remove *** quality of the herb is determined by the quality of the *** traditional *** seedling production technique has nonuniform seedlings and low *** plug seedling technique was used to produce *** *** study was conducted to determine the growth characteristics of *** seedlings according to the cell size of plug trays and number of days after *** height,stem diameter,rhizome diameter,number of leaves,leaf area,and shoot dry and fresh weight of *** seedlings were significantly higher in the P32-D treatment than in the P72,P50,and P32 treatments,but not significantly different from the P28-D treatment 60 d after *** P28-D treatment resulted in a considerable drop in rhizome fresh weight and healthy seedling index,both of which are key indicators for assessing seedling *** the differences in Pn among treatments were not significantly different,Tr was considerably greater in *** seedlings treated with P32-D and P28-D than in the other three *** P32-D and P28-D treatments had considerably greater potential maximum photochemical efficiency of PSII,quantum yield of photosystem II,photochemical quenching and electron transport rate than the other three *** vitality of *** seedlings was significantly stronger in the P32-D treatment than in the other four treatments,and it was 1.9 times higher than in the P28-D *** soluble protein,soluble sugar,and starch contents of *** seedlings were highest in the P32-D treatment,but the differences among treatments were not ***,EUE,PY and EY were significantly higher in the P32-D treatment than in the other four treatments,being 1.3,1.3,1.4 and 1.4 times higher than in P28-D,*** the other hand,as for the change in the gro

关键词： Atractylodes Chinensis(DC)Koidz plug seedling plug tray cell size

Precursory atmospheric teleconnection patterns for strong Siberian High events

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Atmospheric and Oceanic Science Letters 2023年第5期16卷 17-21页

作者： Jian Song Ning shi Qilei Huang Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science and TechnologyNanjingChina College of Atmospheric Science Nanjing University of Information Science and TechnologyNanjngChina

本文利用日本55年逐日再分析资料,发现在SH异常增强前,有三种不同的大气遥相关型前兆信号,即斯堪的纳维亚(SCA)型,西太平洋(WP)型,极地-欧亚(POL)型据此,本文将异常增强的SH分为对应的三类事件.合成结果表明,三类事件在典型环流特征和... 详细信息

本文利用日本55年逐日再分析资料,发现在SH异常增强前,有三种不同的大气遥相关型前兆信号,即斯堪的纳维亚(SCA)型,西太平洋(WP)型,极地-欧亚(POL)型据此,本文将异常增强的SH分为对应的三类事件.合成结果表明,三类事件在典型环流特征和对东亚气温的影响上存在着明显的不同.具体而言,SCA类事件主要表现为在欧亚中高纬度上自西向东的波列异常,WP类事件表现为环流异常自下游太平洋/俄罗斯远东地区向西发展的特征,POL型事件的显著信号则来源于自极区向南移动的反气旋式环流异常.在对东亚地表气温的影响上,SCA类与POL类事件类似,它们均可造成大范围的低温异常.而WP类仅在我国北方和东部地区造成强度较弱的地表气温异常,但该异常的持续性特征较明显。

关键词：西伯利亚高压大气遥相关气温异常

DYNAMICS OF LITTER DECOMPOSITION AND SEASONAL DYNAMICS OF PHOSPHORUS IN DECOMPOSED RESIDUA OF Calamagrotis augustifolia IN THE WETLAND OF THE SANJIANG PLAIN

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Chinese Geographical Science 2001年第3期11卷 73-78页

作者： shi-yan Wang Yong-xing Yang Laboratory of Wetland Environment Changchun Institute of Geography the Chinese Academy of Sciences Changchun P. R. China

During the period of May to October in1999,systematical studies were giv en to the rate of decomposition of Calamagrostis angustifolia litter,the phosphorus content and weight in decomposed residua of litte r,and phosphorus content in the corresponding soil in the Sanjiang *** the same time,the simulation models were listed in the *** results showed that the rate of we ight lost of decomposition of Calamagrostis angustifolia litter is 29.80%and the maximum of daily rate of weight lost i s 0.25%,which appeared in *** c hange trend of phosphorus content an d weight in the decomposed residua of l itter is to reduce with the decomposing process,when it comes to the day of157,the decrement amount of the both were respectively 57.69mg /kg and 1.6199mg,which were 72.80%and 76.30%of its previous *** addition,th ere is a polynomial minus correlatio nship of phosphorus content between the variation in corresponding soil and the decomp osed residua of litter at the corresp onding *** study will be help ful to further understand the process and mechanis m of biochemical cycling of nutrient elements in wetland ecosystems,in a ddition,it will also be helpful to the restoration and rebuilding of retrogressive wetlands and reasonable development and utilization of wetlands in the Sanjiang Plain.

关键词： Calamagrostis angustifolia litter decomposed residua phosph orus seasonal dynamics Sanjiang Plain

休眠期前后樟子松树干液流变化特征及其对环境因子的响应

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水土保持研究 2025年第2期32卷 215-223页

作者：师劭彤李森冯超群程少颖雷声坤刘忠华北京林业大学生物科学与技术学院北京100083 林木育种与生态修复国家工程研究中心北京100083 榆林市榆阳区林业局陕西榆林719000

[目的]探究毛乌素沙地樟子松不同时期耗水量规律,阐明其对多种环境因子的响应关系,揭示樟子松树干液流速率由生长期向休眠期的变化过程。[方法]2023年9月1日—12月21日利用热扩散探针技术连续监测樟子松液流变化,同步测量了大气温度、... 详细信息

[目的]探究毛乌素沙地樟子松不同时期耗水量规律,阐明其对多种环境因子的响应关系,揭示樟子松树干液流速率由生长期向休眠期的变化过程。[方法]2023年9月1日—12月21日利用热扩散探针技术连续监测樟子松液流变化,同步测量了大气温度、太阳辐射以及饱和水汽压亏缺等多个环境因子。[结果](1)在整个观测期内随休眠季来临大气温度、太阳辐射、饱和水汽压差均呈现出逐渐降低的显著性季节变化趋势。(2)在日尺度上11月4日前樟子松树干液流存在显著的昼高夜低的单峰曲线,4日之后其液流昼夜变化没有明显的规律,故定义2023年该试验地樟子松林于11月4日开始进入休眠期。(3)在休眠前期樟子松液流日积累过程呈现“S”型,胸径不同液流日积累总量存在显著差异。(4)在休眠前期和休眠期内樟子松对环境因子的响应程度不同,进入休眠期后其树干液流较为稳定,影响液流速率的因素明显减少。[结论]毛乌素地区樟子松树干液流在11月初开始进入休眠期,休眠前期树干液流主要受大气温度、空气相对湿度以及饱和水汽压差的影响,其树干液流速率呈现显著的“先升高后降低”趋势,随休眠期来临影响树干液流的因素显著减少,液流变化趋势趋于稳定。

关键词：樟子松树干液流日变化环境因子

Generalized system function analysis of resonant behavior of electromagnetic open systems

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Science in China(Series F) 2005年第5期48卷 615-631页

作者： LI Long LIU Haixia shi Yan LIANG Changhong National Laboratory of Antennas and Microwave Technology Xidian University Xi'an 710071 China Institute of Signal and Data Processing Xidian University Xi'an 710071 China

Abstract The generalized system function, H（s）, directly associated with the radiated or scattered fields is presented to effectively analyze the special resonant behavior of electromagnetic open systems in this paper, which is adaptively constructed by using the model-based parameter estimation （MBPE） technique in the complex frequency domain. By analyzing the characteristics of complex zeros, poles and residues of H（s） in a finite operational frequency band, we can effectively determine resonant frequencies and resonant intensity of electromagnetic open systems. It is known that an analysis of Q-factor of antenna and scattering systems has been an interesting and challenging problem. Based on H（s） and the complex frequency w theories, a complex frequency method for Q-factor of electromagnetic open systems is presented in this paper. Some examples of the practical antenna arrays are given to illustrate the applications and validity of the generalized system function theory proposed by this paper.

关键词： Keywords: generalized system function H(s) electromagnetic open resonance complex frequency qualityfactor Q model-based parameter estimation (MBPE)

Highly rarefied gas flows in rough channels of finite length

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Advances in Aerodynamics 2023年第1期5卷 558-578页

作者： Zheng shi Yulong Zhao Wei Su Lei Wu Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China Division of Emerging Interdisciplinary Areas The Hong Kong University of Science and TechnologyClear Water BayHong KongChina Department of Mathematics The Hong Kong University of Science and TechnologyClear Water BayHong KongChina

Highly rarefied gas flows through a rough channel of finite length with small bumps appended to its surfaces are investigated,by varying the accommodation coefficientin Maxwell’s diffuse-specular boundary condition,the characteristic size and position of the bumps,and the channel ***,we study the influence of the surface bumps and consider the rarefied gas flow in a unit channel with periodic boundary conditions to remove the end *** is found that the surface bumps have a significant impact on the flow ***is very small(i.e.,nearly specular reflection of gas molecules at the channel surface),the apparent gas permeability is dramatically reduced,even in the presence of small bumps,to a value that is almost comparable to the one when fully diffuse gas-surface scattering is *** impact can be taken into account through an effective accommodation coefficient,i.e.,the permeability of the rough channel is taken equivalently as that of a smooth channel without bumps but having gas-surface scattering under the effective accommodation ***,we study the end effect by connecting a smooth channel of length L_(0) to two huge gas *** is found that(i)the end correction length is large at small.Consequently,the mass flow rate barely reduces with increasing L_(0) rather than scales down by a factor of 1/L_(0) as predicted by the classical Knudsen diffusion theory;and(ii)the end correction is related to the channel’s aspect ***,based on the effective accommodation coefficient and end correction,we explain the exotic flow enhancement in graphene angstrom-scale channels observed by Geim’s research group(Keerthi et al,Nature 558:420-424,2018).

关键词： Rarefied gas Accommodation coefficient Rough channel End effect

Development and validation of an RP-HPLC method for simultaneous determination of Ramipril and Amlodipine in tablets

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Journal of Pharmaceutical Analysis 2013年第6期3卷 440-446页

作者： shi-Ying Dai shi-Ting Qiu Wei Wu Chun-Mei Fu Key Laboratory of Drug Targeting and Drug Delivery System Ministry of EducationWest China School of Pharmacy Sichuan University

AnRP-HPLC method for the simultaneous determination ofRamipril （RP） andAmlodipine （AL） in tablets was developed and validated by Chinese Pharmacopoeia 2010. The linearity of the proposed method was investigated in the range of 0.01-0.25 mg/mL （r^2=0.9998） for RP and 0.014-0.36 mg/mL （r^2=0.9997） for AL. The limits of detection （LOD） were 0.06 lag/mL and 0.02 μg/mL for RP and AL, and the limits of quantitation （LOQ） were 0.2 Dg/mL and 0.07 μg/mL, respectively. Some major impurities and degradation products did not disturb the detection of RP and AL and the assay can thus be considered stability-indicating.

关键词： Ramipril Amlodipine RP-HPLC Stability-indicating

Microstructure and mechanical properties of laser additive manufactured novel titanium alloy after heat treatment

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China Foundry 2021年第6期18卷 574-580页

作者： Tian-yu Liu Hong-yu Liu Qian Yao shi-bing Liu Kun shi Zhi-yong Zhang Chong-yang Li Shenyang Research Institute of Foundry Co. Ltd.Shenyang 110022China State Key Laboratory of Light Alloy Casting Technology for High-end Equipment Shenyang 110022China

A novel α+β titanium alloy with multi-alloying addition was designed based on the cluster formula 12[Al-Ti_(12)](AlTi_(2))+5[Al-Ti_(14)](AlV_(1.2)Mo_(0.6)Nb_(0.2))which was derived from *** nominal composition of this novel alloy was determined as *** this study,the novel alloy and Ti-6Al-4V alloy samples were prepared by laser additive *** microstructure,micro-hardness,room/high temperature tensile properties of the as-deposited samples were *** to Ti-6Al-4V,the novel alloy has much higher room and high temperature(600℃)tensile strengths,which are 1,427.5 MPa and 642.2 MPa,respectively;however,it has a much lower elongation(3.2%)at room temperature because of the finer *** improve the elongation of the novel alloy,heat treatment was *** solution at 960℃ or 970℃ for 1 h followed by air cooling and aging at 550℃ for 4 h followed by air cooling,a unique bi-modal microstructure which contains crab-like primaryαand residual β phase is obtained,improving the compression elongation by 80.9% compared to the as-deposited *** novel alloy can be used as a high-temperature and high-strength candidate for laser additive manufacturing.

关键词： laser additive manufacturing titanium alloy composition design heat treatment

Error Analysis of Three Degree-of-Freedom Changeable Parallel Measuring Mechanism

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Journal of China University of Mining and Technology 2007年第1期17卷 101-104页

作者： CHENG Gang GE shi-rong WANG Yong Institute of Reliability and Rescue Robotics China University of Mining ＆Technology Xuzhou Jiangsu 221008 China

A three degree-of-freedom (DOF) planar changeable parallel mechanism is designed by means of control of different drive parameters. This mechanism possesses the characteristics of two kinds of parallel mechanism. Based on its topologic structure, a coordinate system for position analysis is set-up and the forward kinematic solutions are analyzed. It was found that the parallel mechanism is partially decoupled. The relationship between original errors and position-stance error of moving platform is built according to the complete differential-coefficient theory. Then we present a special example with theory values and errors to evaluate the error model, and numerical error solutions are gained. The investigations concentrating on mechanism errors and actuator errors show that the mechanism errors have more influences on the position-stance of the moving platform. It is demonstrated that improving manufacturing and assembly techniques can greatly reduce the moving platform error. The small change in position-stance error in different kinematic positions proves that the error-compensation of software can improve considerably the precision of parallel mechanism.

关键词： parallel mechanism changeable measuring mechanism kinematics forward analysis error model error analysis