检索结果-南通市图书馆

太原市5种常绿植物入冬期间叶片SPAD值的变化特征

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

陕西林业科技 2024年第2期52卷 9-14页

作者：昌秦湘何雯杰杨晓琴夏鹏国梁宗锁太原学院园林科学研究所太原030032 浙江理工大学生命科学与医药学院杭州310018

SPAD值能够反映植物叶片叶绿素含量,是表征植物生长状况的重要指标.以太原市5种常绿植物为研究对象,分别测定其在入冬期间的SPAD值,结合气象数据,运用方差分析、主成分分析和相关性分析,总结其在入冬期间SPAD值的变化特征.结果表明:入... 详细信息

SPAD值能够反映植物叶片叶绿素含量,是表征植物生长状况的重要指标.以太原市5种常绿植物为研究对象,分别测定其在入冬期间的SPAD值,结合气象数据,运用方差分析、主成分分析和相关性分析,总结其在入冬期间SPAD值的变化特征.结果表明:入冬期间,刚竹和胶东卫矛的SPAD值整体表现为随时间推移而逐渐降低的趋势;巴山箬竹的SPAD值随时间推移变化幅度较小;刚竹、胶东卫矛的SPAD值与气温之间呈显著正相关(P<0.01),粗榧的SPAD值则与气温之间呈显著负相关(P<0.01),表明这三种植物的SPAD值受温度影响较大;小叶黄杨的SPAD值与相对湿度呈显著负相关(P<0.05);主成分分析将6个气象指标归纳成两个综合因子,分别为直接对叶片SPAD值影响的温度和间接对叶片SPAD值影响的相对湿度和日照时长.在园林应用方面,5种常绿植物在太原市入冬期均表现良好.本研究可为太原市园林植物选择、配置及养护管理提供参考依据.

关键词： SPAD 植物太原市入冬期

Suitable soil moisture contents for water use efficiency and saponins accumulation in Panax notoginseng

在线全文

学校读者我要写书评

暂无评论

Chinese Herbal Medicines 2021年第2期13卷 267-273页

作者： Yu-jie Zheng peng-guo xia Hong-guang Zhao Jian-fen Zheng Wei-guo Chai Zong-suo Liang Kai-jing Yan Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province College of Life Sciences and MedicineZhejiang Sci-Tech UniversityHangzhou 310018China Institute of Biotechnology Hangzhou Academy of Agricultural SciencesHangzhou 310024China Yunnan TASLY Notoginseng Pharmaceutical Co. LtdWenshan 663000China

Objective:The moisture content in the soil directly affects the yield and quality of Panax notoginseng,especially at the age of three years ***,the suitable moisture for the growth of *** is *** this study,the effects of different soil moisture on the growth of *** were ***:Four different water treatments(0.45 field capacity(FC),0.60 FC, 0.70 FC, and 0.85 FC) were set up in Shilin County,Yunnan Province,*** water consumption and daily dynamic of water consumption were determined daily(from April 21 to October 18,2012),and the daily dynamic of water consumption under different weather conditions(sunny and rainy) was *** transpiration coefficient and water use efficiency were calculated through dry matter accumulation and total water *** of saponins of roots of *** were analyzed by HPLC after treated,and the soil moisture content suitable for the growth of *** was estimated by regression fitting of the active ingredient accumulation and the soil moisture ***:The water consumption of 0.85 FC,0.70 FC,0.60 FC and 0.45 FC were 2.89,3.68,3.37 and 2.73 kg/plant per day,*** water consumption of *** from June to August was greater than other *** daily dynamic of water consumption on sunny days and sunny days after rain showed a "double peak" feature,and it showed a "single peak" feature on rainy *** water uses efficiency(WUE) of 0.85 FC,0.70 FC,0.60 FC and 0.45 FC were 2.51,3.32,4.59,3.39 gDW/kg H_(2)O,*** increase of soil moistu re content would reduce the WUE of *** *** the increase of soil water content,the content of notoginsenoside R_(1) and ginsenoside Rg_(1) did not change significantly,while the content of ginsenoside Rb_(1) and Rd showed a decreasing ***:Soil moisture content significantly affected the water consumption of ***,and when it was 56.4% of the maximum water h

关键词： Panax notoginseng(Burk.)F.H.Chen saponins transpiration coefficient water consumption dynamics water use efficiency

Thickening progression mechanism of silica fume-oil well cement composite system at high temperatures

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第4期21卷 2793-2805页

作者： Hang Zhang Miao-Miao Hu peng-peng Li guo-Qing Liu Qing-Lu Chang Jie Cao Ming Liu Wen-Hua Xu Xiu-Jian xia Jin-Tang guo School of Chemical Engineering and Technology Tianjin University Zhejiang Institute of Tianjin University Haihe Laboratory of Sustainable Chemical Transformations CNPC Engineering Technology R&D Company Limited

This work studied the thickening progression mechanism of the silica fume-oil well cement composite system at high temperatures(110-180.C) in order to provide a theoretical guidance for the rational application of silica fume in the cementing engineering. Results showed that silica fume seldom affected the thickening progression of oil well cement slurry at 110-120.C, but when temperature reached above130.C, it would aggravate the bulging degree of thickening curves and significantly extend the thickening time, meanwhile causing the abnormal “temperature-based thickening time reversal” and“dosage-based thickening time reversal” phenomena in the range of 130-160.C and 170-180.C respectively. At 130-160.C, the thickening time of oil well cement slurry was mainly associated with the generation rate of calcium hydroxide(CH) crystal. The introduced silica fume would be attracted to the cement minerals' surface that were hydrating to produce CH and agglomerate together to form an“adsorptive barrier” to hinder further hydration of the inner cement minerals. This “adsorptive barrier”effect strengthened with the rising temperature which extended the thickening time and caused the occurrence of the “temperature-based thickening time reversal” phenomenon. At 170-180.C, the pozzolanic activity of silica fume significantly enhanced and considerable amount of C-S-H was generated, thus the “temperature-based thickening time reversal” vanished and the “dosage-based thickening time reversal” was presented.

关键词： Silica fume Oil well cement Thickening time reversal Pozzolanic reaction Adsorptive barrier CH and C−S−H

Configuration Synthesis and Grasping Performance Analysis of Multi-Loop Coupling Capture Mechanism for Launch and Recovery of Torpedo-Shaped Autonomous Underwater Vehicle

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

China Ocean Engineering 2024年第3期38卷 453-466页

作者： ZHANG guo-xing xia Xin-lu guo Jin-wei School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Research of capture mechanisms with strong capture adaptability and stable grasp is important to solve the problem of launch and recovery of torpedo-shaped autonomous underwater vehicles(AUVs).A multi-loop coupling capture mechanism with strong adaptability and high retraction rate has been proposed for the launch and recovery of torpedo-shaped AUVs with different morphological ***,the principle of capturing motion retraction is described based on the appearance characteristics of torpedo-shaped AUVs,and the configuration synthesis of the capture mechanism is carried out using the method of constrained chain ***,the screw theory is employed to analyze the degree of freedom(DoF)of the capture ***,the 3D model of the capture mechanism is established,and the kinematics and dynamics simulations are carried *** with the capture orientation requirements of the capture mechanism,the statics and vibration characteristics analyses are carried ***,considering the capture process and the underwater working environment,the motion characteristics and hydraulics characteristics of the capture mechanism are ***,a principle prototype is developed and the torpedo-shaped AUVs capture experiment is *** work provides technical reserves for the research and development of AUV capture special equipment.

关键词： capture mechanism torpedo-shaped AUVs configuration synthesis launch and recovery grasping performance analysis

Nuclei-rich galvanizing strategy for suppressing zinc dendrite growth

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第8期43卷 4016-4018页

作者： Hai-xia Wu Kai-Lu guo College of Chemistry and Chemical Engineering Henan Key Laboratory of Function-Oriented Porous MaterialsLuoyang Normal UniversityLuoyang 471934China

The uncontrolled growth of zinc dendrites on zinc anode hinders the application of zinc ion *** solve this problem,Lu's group proposed a nuclei-rich galvanizing strategy for suppressing the zinc dendrite *** allows the nuclei-rich zinc electrode to cycle steadily for1200 h and have a high Coulombic efficiency of 99.7%at15 mA·cm^(-2)with a deposited amount of 10 mAh·cm^(-2).Moreover,the Zn-MnO_(2) battery with a low N/P ratio of 1.9exhibited sustained cycling life.

关键词： cycling sustained battery

Regio-and Stereoselective Polymerization of Bio-based Ocimene by Rare-Earth Metal Catalysts

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第2期42卷 223-229,I0008页

作者： Qi-Yuan Wang Li-peng Sang Zhen Zhang Yang Jiang Hui Tian xia Zhao xiang guo Shi-Hui Li State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China Science and Technology on Aerospace Chemical Power Laboratory Hubei Institute of Aerospace ChemotechonologyXiangyang441003China Shanxi Coal Chemical Industry Technology Research Institute Xi’an710000China Hubei Institute of Aerospace Chemotechonology Xiangyang441003China

Coordination polymerization of renewable β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-sandwich benzyl fluorenyl scandium complex 4 and pyridyl-methylene-fluorenyl rare-metal complexes 5a–5c. Complexes 1, 4 and 5a–5c show trans-1,2-regioselectivities and high activities, of which 5c exhibits excellent isoselectivity(mmmm>99%). Conversely, complexes 2 and 3 promote β-ocimene polymerization to produce isotactic cis-1,4-polyocimenes(cis-1,4>99%, mm>95%). Diblock copolymers cis-1,4-PIP-block-cis-1,4-POc and cis-1,4-PBD-block-cis-1,4-POc are obtained in one-pot reactions of β-ocimene with isoprene and butadiene using complex 3. Epoxidation and hydroxylation of polyocimene afford functionalized polyolefins with enhanced T_(g)(from-20 ℃ to 79 ℃ and 74 ℃) and hydrophilicity.

关键词： Biobased monomer Terpenes Ocimene Rare-earths Polymerization Regio/stereoselectivity Elastomer

Arbitrary High-Order Fully-Decoupled Numerical Schemes for Phase-Field Models of Two-Phase Incompressible Flows

在线全文

学校读者我要写书评

暂无评论

Communications on Applied Mathematics and Computation 2024年第1期6卷 625-657页

作者： Ruihan guo Yinhua xia School of Mathematics and Statistics Zhengzhou UniversityZhengzhou450001HenanChina School of Mathematical Sciences University of Science and Technology of ChinaHefei230026AnhuiChina

Due to the coupling between the hydrodynamic equation and the phase-field equation in two-phase incompressible flows,it is desirable to develop efficient and high-order accurate numerical schemes that can decouple these two *** popular and efficient strategy is to add an explicit stabilizing term to the convective velocity in the phase-field equation to decouple *** resulting schemes are only first-order accurate in time,and it seems extremely difficult to generalize the idea of stabilization to the second-order or higher *** this paper,we employ the spectral deferred correction method to improve the temporal accuracy,based on the first-order decoupled and energy-stable scheme constructed by the stabilization *** novelty lies in how the decoupling and linear implicit properties are maintained to improve the *** the framework of the spatially discretized local discontinuous Galerkin method,the resulting numerical schemes are fully decoupled,efficient,and high-order accurate in both time and *** experiments are performed to validate the high-order accuracy and efficiency of the methods for solving phase-field models of two-phase incompressible flows.

关键词： Two-phase incompressible flows Fully-decoupled High-order accurate Linear implicit Spectral deferred correction method Local discontinuous Galerkin method

Zeolite polymer membrane as protective interface for Mg battery

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第9期43卷 4636-4638页

作者： Hai-xia Wu Kai-Lu guo College of Chemistry and Chemical Engineering Henan Key Laboratory of Function-Oriented Porous MaterialsLuoyang Normal University

Excessive electrolyte decomposition seriously determines the performance of high-voltage Mg batteries. In Nazar?s work, the strategy using a zeolite polymer membrane as a protective interface was proposed to restrain the electrolyte decomposition. This strategy could boost Mg plating/stripping performance up to 6000 h in zeolite/Mg|zeolite/Mg symmetric cells and 91%capacity retention in zeolite/Mg||Mo3S4battery after 200 *** storage devices have been intensively explored because of their important roles in our daily lives [1D3].

关键词：

Evaluation of water management on arsenic methylation and volatilization in arsenic-contaminated soils strengthened by bioaugmentation and biostimulation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第3期137卷 515-526页

作者： peng Chen Yi Liu guo-Xin Sun State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China University of Chinese Academy of Sciences Beijing 100049China

Arsenic(As) fate in paddy fields has been one of the most significant current issues due to the strong As accumulation potential of rice plants under fooded conditions. However,no attempt was done to explore As methylation and volatilization under non-fooded conditions. Herein, we investigated the effects of water management on As methylation and volatilization in three arsenic-contaminated soils enhanced by biostimulation with strawderived organic matter and bioaugmentation with genetic engineered Pseudomonas putida KT2440(GE P. putida). Under fooded conditions, the application of biochar(BC), rice straw(RS)and their combination(BC+RS) increased total As in porewater. However, these effects were greatly attenuated under non-fooded conditions. Compared with RS amendment alone, the combination of GE P. putida and RS further promoted the As methylation and volatilization,and the promotion percentage under non-fooded conditions were significantly higher than that under fooded conditions. The combined GE P. putida and RS showed the highest efficiency in As methylation(88 μg/L) and volatilization(415.4 μg/(kg·year)) in the non-fooded soil with moderate As contamination. Finally, stepwise multiple linear regression analysis presented that methylated As, DOC and p H in porewater were the most important factors contributing to As volatilization. Overall, our findings suggest that combination of bioaugmentation with GE P. putida and biostimulation with RS/BC+RS is a potential strategy for bioremediation of arsenic-contaminated soils by enhancing As methylation and volatilization under non-fooded conditions.

关键词： Arsenic methylation Arsenic volatilization Water management Straw incorporation Bioaugmentation