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Anatomical variations of living and fossil Liquidambar leaves:A proxy for paleoenvironmental reconstruction

Science China Earth Sciences 2011年第4期54卷 493-508页

作者： xiAO Liang 1,2.3,4.SUN BaiNian 1,2.,LI xiangChuan 1,REN Wenxiu 1 &JIA Hui 1 1 Key Laboratory of Western China's Environmental Systems of the Ministry of Education and college of Earth and Environment Science,Lanzhou university,Lanzhou 730000,China 2.State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of {2. and Palaeontology,Chinese Academy of Sciences,Nanjing 2.0008,China 3 college of Arts and Sciences,Bryant university,Smithfield RI 02.17,U.S.A. 4.Key Laboratory of Western China's Mineral Resources and Geological engineering of Ministry of Education,chang’an university,xi’an 710054,China 1. Key Laboratory of Western China’s Environmental Systems of the Ministry of Education and college of Earth and Environment Science Lanzhou University Lanzhou 730000 China2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China3. College of Arts and Sciences Bryant University Smithfield RI 02917 USA4. Key Laboratory of Western China’s Mineral Resources and Geological Engineering of Ministry of Education Chang’an University Xi’an 710054 China

Based on living ***,we have established that such epidermal cell properties as epidermal cell circumference(Circum.) ,undulation index(UI) ,epidermal cell area(EA) on both upper and lower epidermis and the corresponding epidermal cell density(ED) ,are suitable to differentiate between sun and shade ***,stomatal properties on the lower epidermis,including stomatal length(SL) ,stomatal pore length(PL) and the corresponding stomatal density(SD) ,are reliable parameters to identify sun/shade *** this anatomical approach was applied to 18 leaf remains of *** from the Miocene xiannanshan Formation,Zhejiang Province(eastern China) ,and the fossil leaves were sorted into two groups,namely,sun and shade *** indicates that anatomical differences between sun and shade leaves found in living species could be used for fossil ***,the variation of UI between sun and shade morphotypes is larger on the upper epidermis as compared with the lower epidermis,showing that the UI on the upper epidermis is more sensitive to environmental *** addition,anatomical features are more variable in sun leaves than in shade leaves for both modern and fossil Liquidambar,suggesting sun leaves may be more sensitive to environmental *** leaves can then be a better indicator of paleoenvironmental ***,stomatal parameters of sun morphotype should be adopted on reconstructing paleoenvironments using Liquidambar leaf *** the other hand,the three-lobed fossil *** leaf assemblage in the xiananshan Formation is represented by an almost similar percentage of sun and shade morphotypes(56%and {2.%,respectively) ,which is attributed to the short transport before *** a result,identifying sun/shade morphotypes are very useful in reconstructing paleoenvironments based on fossil leaves of Liquidambar.

关键词： Liquidambar formosana Liquidambar miosinica leaf anatomy the Miocene xiananshan Formation sun and shade leaves

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Experimental investigation of dynamic characteristics of leaching tubing for solution mining of salt cavern carbon and energy storage

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Petroleum Science 2024年第4期21卷 2703-2722页

作者： Yin-Ping Li xin-Bo Ge xi-Lin Shi Hong-Ling Ma State Key Laboratory of Geomechanics and Geotechnical engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences university of Chinese Academy of Sciences college of Energy and Mining engineering Shandong University of Science and Technology State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and Technology

Salt caverns are extensively utilized for storing various substances such as fossil energy, hydrogen,compressed air, nuclear waste, and industrial solid waste. In China, when the salt cavern is leached through single-well water solution mining with oil as a cushion, engineering challenges arise with the leaching tubing, leading to issues like damage and instability. These problems significantly hinder the progress of cavern construction and the control of cavern shape. The primary cause of this is the flowinduced vibration instability of leaching tubing within a confined space, which results in severe bending or damage to the tubing. This study presents a model experimental investigation on the dynamic characteristics of leaching tubing using a self-developed liquid-solid coupling physical model experiment apparatus. The experiment utilizes a silicone-rubber pipe(SRP) and a polycarbonate pipe(PCP) to examine the effects of various factors on the dynamic stability of cantilevered pipes conveying fluid. These factors include external space constraint, flexural rigidity, medium outside the pipe, overhanging length, and end conditions. The experiments reveal four dynamic response phenomena: water hammer, static buckling, chaotic motion, and flutter instability. The study further demonstrates that the length of the external space constraint has a direct impact on the flutter critical flow velocity of the cantilevered pipe conveying fluid. Additionally, the flutter critical flow velocity is influenced by the end conditions and different external media.

关键词： Salt cavern storage Solution mining Leaching tubing Experimental investigation Flutter instability

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Controlling reversible complexation-mediated polymerization(RCMP)via deep eutectic solvents:fast kinetics,narrow molecular weight distribution and mechanistic insights

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Science China Chemistry 2024年第8期67卷 2728-2736页

作者： xin Fu Zhen Lu Shen Li Zheng-Hong Luo Lin-xi Hou Department of Materials-Oriented Chemical engineering College of Chemical EngineeringFuzhou UniversityFuzhou 350116China Department of Chemical engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200030China Chemical engineering Zhicheng College of Fuzhou UniversityFuzhou 350116China Qingyuan Innovation Laboratory Quanzhou 362801China

The exploitation of new green polymerization avenues for the effective synthesis of polymers by reversible-deactivation radical polymerization plays a critical role in pursuing the development of polymeric *** this work,serials of deep eutectic solvents(DES)with intermolecular-hydrogen-bonding interaction were constructed as catalysts and medium for actuating reversible complexation-mediated polymerization(RCMP)for the first time,yielding methacrylate polymers with high monomer conversion and narrow dispersion molecular weight in both water and oil *** mechanism and elementary reaction of RCMP were explored deeply,revealing that the complexation of initiator with DES to generate radicals was a ratecontrolling step and intermolecular-hydrogen-bond was primary factor to influence polymerization ***,the insights of density functional theory calculations revealed that negative electrostatic potential ensured nucleophilic *** investigation demonstrated the considerable potential of DES for RCMP,which is anticipated for other polymerization applications as a novel medium mode.

关键词： deep eutectic solvent reversible complexation-mediated polymerization intermolecular hydrogen bonding density functional theory elementary reaction steps

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Synthesis and reactivity of cobalt dinitrogen complex supported by nonsymmetrical pincer ligand

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Chinese Chemical Letters 2024年第7期35卷 259-263页

作者： Yuanjin Chen xianghui Shi Dajiang Huang Junnian Wei Zhenfeng xi Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of ChemistryPeking UniversityBeijing 100871China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryShanghai 200032China

A nonsymmetrical PNN pincer ligand[6-(^(t)Bu_(2.PNH)C_(5)H_(4.N-2.(3-Mes)C_(3)H_(2.N_(2.]and its corresponding cobalt-N_(2.complex were synthesized and *** the stoichiometric reaction of the PNN ligand lithium salt with CoCl_(2.,the complex 3,(PNN)CoCl,was ***,reduction of 3 with NaBHEt3under a dinitrogen atmosphere yielded complex 5,(PNN)Co(Ⅰ)(η^(1)-N_(2.).Single-crystal X-ray analysis,IR spectrum,and DFT calculations revealed that the dinitrogen in 5 was only weakly reduced by the cobalt *** reactions of 5 with carbon monoxide and 2.6-dimethylphenyl isocyanide gave carbonyl and isocyanide complexes 6 and 7 with the release of N_(2.,***,these cobalt complexes,especially complex 5,demonstrated the capacity to convert dinitrogen to N(TMS)_(3)with moderate efficiency.

关键词： Dinitrogen fixation Dinitrogen transformation Nonsymmetrical pincer ligand Cobalt complex Catalytic silylamine formation

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Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2. ZHANG Jiao qiang 3 (1. Department of Chemistry,Northwest university, xi′an 710065, China 2. Department of Chemistry and Chemical {2., Baoji {2. of Arts and Science, Baoji 72.007, China 3. Department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

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Digital close-range photogrammetric application to small-scale physical simulation experiment

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中国有色金属学会会刊：英文版 2011年第S3期21卷 681-685页

作者： LI Chun-yi1, CUI xi-min2. YU Yi-ju3 1. School of Surveying and Landing Information engineering, Henan Polytechnic {2., Jiaozuo 4.4.03, China 2. {2. of Geoscience and Surveying engineering, China {2. of Mining and Technology, Beijing 100083, China 3. Surveying and Mapping Press, Beijing 10004., China [a] School of Surveying and Landing Information engineering Henan Polytechnic University Jiaozuo 454003 China [b] college of Geoscience and Surveying engineering China University of Mining and Technology Beijing 100083 China [c] Surveying and Mapping Press Beijing 100045 China

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.131 mm and vertical direction is ±0.192.mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

关键词： close-range photogrammetric physical simulation light-rays adjustment surveying precision subsidence factor

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Influence of Interpenetrating Polymer Networks (IPN) Microstructure on Underwater Acoustic Stealth Performance

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Journal of Wuhan university of Technology(Materials Science) 2010年第2期25卷 272-277页

作者：罗忠 college of Naval Architecture and Power Naval University of Engineering

According to the configuration and absorption theory of polymer macromolecule materials, a kind of IPN with wider temperature range and higher damping property was designed and synthesized. By using the spectrum of dynamic mechanical thermal analysis （DMTA） and acoustic pulse tube device, the microstructure, phase separation degree, phase size and phase continuity of IPN with different components were analyzed. The experimental results show that the nano size grade of phase, the continuous and homogeneous IPN phase can provide higher absorption coefficient. The absorption coefficient of optimized sample I09 is 0.7 in 2.kHz, and the absorption peak is 0.9 in 4.kHz. Then the underwater acoustic properties of modified IPN filled with mica, micro-balloon and nano-SiO2.were discussed respectively to indicate that the inhomogeneous property of filler-modified IPN can improve the underwater acoustic stealth performance effectively, and the micro size grade of these filler-modified IPN can work well in low frequency acoustic stealth.

关键词： interpenetrating polymer networks (IPN) polyurethane damping absorption coefficient fillers

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Rational cathode configuration with bilayer membranes to engineer current-collector-free high-areal-sulfur lithium-sulfur batteries

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Nano Research 2024年第6期17卷 5224-5232页

作者： Jianmei Han Hua Zhang Peng Wang Ning Song Xuguang An Baojuan xi Shenglin xiong college of Chemistry and Chemical engineering Taishan UniversityTai’an 271021China Key Laboratory of the Colloid and Interface Chemistry Ministry of Educationand School of Chemistry and Chemical EngineeringShandong UniversityJinan 250100China School of Mechanical engineering Chengdu UniversityChengdu 610106China

The application of light-weight current collectors is preferred because of the increased energy density of the *** it in mind,the cathode is designed with self-made paperlike memberane as current collector coupled with another interlayer to enable the high-energy-density lithium-sulfur *** a facile and green step-by-step methodology,the hybrid membrane is finalized successfully,consisting of reduced graphene oxide sheets covering paper-derived carbon(GPC)bearing Fe@Fe2.3 and Fe1−xS@Fe2.3 core-shell nanoparticles(FeFeO/FeSFeO@GPC).The film works as the current collector and interlayer simultaneously considering the porous and conductive *** demonstrated by the electrochemical testing,the FeFeO/FeSFeO@GPC hybrid cell exhibits attractive cycling stability and superior rate *** cell configuration and structural/composition merits of FeFeO/FeSFeO@GPC film facilitate the faster reaction kinetics,conducive to the improvement of capacity *** view of the effective cathode design,the areal sulfur loading is increased to 10.4. mg·cm^(−2.and a reversible capacity of 6.67 mAh·cm^(−2.can be retained after 60 cycles at 0.1 C.

关键词： light-weight self-made current collector core-shell high-areal-sulfur lithium-sulfur batteries

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Triboelectric nanogenerator integrated with a simple controlled switch for regularized water wave energy harvesting

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Nano Research 2024年第8期17卷 7585-7592页

作者： Hongbo Yang xi Liang Junwu Kan Zhong Lin Wang Tao Jiang Zhanyong Hong college of engineering Zhejiang Normal UniversityJinhua 321004China Beijing Key Laboratory of Micro-Nano Energy and Sensor Center for High-Entropy Energy and SystemsBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400China The Beijing Key Laboratory for Nano-Photonics and Nano-Structure Department of PhysicsCapital Normal UniversityBeijing 100048China Guangzhou Institute of Blue Energy Guangzhou 510555China Georgia Institute of Technology AtlantaGA 30332-0245USA Yonsei Frontier Lab Yonsei UniversitySeoul 03722Republic of Korea

Ocean is full of low-frequency,irregular,and widely distributed wave energy,which is suitable as the energy source for maritime Internet of Things(IoTs).Utilizing triboelectric nanogenerators(TENGs)to harvest ocean wave energy and power sensors is proven to be an effective ***,in random ocean waves,the irregular electrical energy output by general TENGs restricts the *** present,achieving regularized water wave energy harvesting relies on rather complex mechanical structure designs,which is not conducive to *** this work,we proposed a novel mechanical controlled TENG(MCTENG)with a simple controlled switch to realize the regularization *** structural parameters of the MC-TENG are optimized,and the optimal output voltage,output current,and transferred charge respectively reach 1684.2.V,85.4.A,and 389.9 nC,generating a peak power density of 38.4. W·m^(−3)·Hz^(−1).Under real water wave environment,the output of the MC-TENG is regularized and keeps stable regardless of any wave ***,the potential applications of the MC-TENG are demonstrated in powering environmental temperature,humidity,and wind speed *** work renders a simple approach to achieve effective regularized ocean wave energy harvesting,promoting the TENG industrialization toward practical application of maritime IoTs.

关键词： water wave energy harvesting triboelectric nanogenerators random excitation mechanical control regular output

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Cushioning Performance of a Novel Polyurethane Foam Material Applied in Fragile Packaging

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Acta Mechanica Solida Sinica 2024年第3期37卷 487-497页

作者： Huifeng xi Chunqiu Guo Jinbiao Yang xiaogang Wang Bowei Wang Shiqing Huang Zhiwei Wang School of Mechanics and Construction engineering Jinan UniversityGuangzhou510632China college of Packing engineering Jinan UniversityZhuhai519070China MOE Key Lab of Disaster Forecast and Control in engineering Jinan UniversityGuangzhou510632China Foshan Soft Valley Technology Co. Ltd.Foshan528000China

For fragile products,packaging requires cushioning protection to prevent irreversible damage from accidental falls,transportation impacts,and other *** new polyurethane foam(PUF)material demonstrates superior cushioning and vibration isolation performance in practical applications,effectively minimizing damage from *** and vibration experiments were conducted on packages comprising novel PUF,expandable polyethylene,ethylene-vinyl acetate copolymer foam,and *** verify that the new PUF material outperforms in cushioning and vibration isolation,as observed from the acceleration ***,a random vibration analysis of a packaging unit involving different thicknesses of PUF materials and bracelets reveals the enhanced vibration isolation effect within a specific thickness *** vibration results of the bracelet’s outer packaging align closely with finite element simulation results,validating the effectiveness of designing and optimizing the outer *** finite element simulation,deeper understanding and prediction of the bracelet’s vibration response under various conditions is achieved,facilitating optimized packaging design for better protection and vibration damping.

关键词： Flexible polyurethane foam Packaging of fragile goods Nonlinear dynamics Vibration frequency Finite element simulation

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