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Inhibitory Effects of 1-MCP and DPA on Superficial Scald of Dangshansuli Pear

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Agricultural Sciences in China 2011年第10期10卷 1638-1645页

作者： HUI Wei NIU rui-xue SONG Yao-qiang LI De-ying College of Life Sciences Shaanxi Normal University Xi＇an 710062 P.R.China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 P.R.China Biological Sciences Department Qinghai University Xining 810061 P.R. China

Dangshansuli pear is one of crisp pears and has a non-climacteric respiratory pattern. Dangshansuli pear fruits were treated with 1 000 or 2 000 μL L-1 diphenylamine （DPA） for 1 min, or with 0.5 μL L-1 1-methylcyclopropene （l-MCP） for 12 h before cold storage at （2±0.5）℃ for up to 210 d. Incidences of superficial scald and related physiological indexes were investigated during storage. The results showed that superficial scald occurred in control fruit with a rate of over 90% after 210 d at cold storage plus 10 d at room temperature. Treatments with 1 000 and 2 000 μL L-1 DPA and 0.5 μL L-1 l-MCP inhibited the accumulation of a-farnesene, conjugated trienes, total phenolic contents, and malondialdehyde （MDA） during storage. The treatments also decreased leakage of cell membrane and the activity of polyphenol oxidase （PPO） in the peel. These results indicate that 1-MCP and DPA treatments inhibit and postpone the occurrence of superficial scald of Dangshansuli pears remarkably in cold storage and post-storage shelf life, respectively, while the mechanisms were different. The results above may provide a theoretical evidence for the agriculture production.

关键词： 1-MCP diphenylamine pear superficial scald

Effect of salt bath temperature on microstructure and mechanical properties of an austempered alloyed cast iron

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China Foundry 2024年第6期21卷 709-716页

作者： Jie Zheng Ji-lin Li Sheng-feng Li Xiao-hui Tu rui-xue Li Institute of Advanced Wear and Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou 510632China Institute of New Materials Guangdong Academy of SciencesGuangzhou 510650China School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150080China

An alloyed cast iron was prepared by horizontal continuous *** study the salt bath temperature on microstructure and mechanical properties,the alloyed cast iron was firstly austenitized at 950℃for 3 h and then austempered in salt bath at various temperatures(250℃,300℃and 350℃)for another 3 *** scanning electron microscopy(SEM),electron backscattered diffraction(EBSD),and X-ray diffraction(XRD)were employed to observe the microstructure and test the mechanical properties of the alloyed cast *** show that the microstructure of the alloyed cast iron is mainly composed of acicular or feathery ferrite(bainite),retained austenite,carbide,and *** austempered in salt bath at 250℃,300℃and 350℃for 3 h,the volume fractions of retained austenite are 33.1%,41.7%,and 57.2%,the thickness of acicular ferrite are 0.25μm,0.3μm,and 0.8μ*** the salt bath austempering temperature increases,the mechanical properties decrease due to the increase of the volume fraction of retained austenite and the thickness of acicular *** highest tensile strength of the alloyed cast iron is achieved when it is austempered at 250℃in a salt *** these conditions,the tensile strength of the alloyed cast iron can reach 1,429 *** test results indicate that the fracture mechanism is predominantly brittle fracture.

关键词： alloyed cast iron austempering treatment retained austenite microstructure mechanical properties

Properties ofπ-skew Graphs with Applications

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Acta Mathematica Sinica,English Series 2021年第4期37卷 641-656页

作者： Zhang Dong OUYANG Feng Ming DONG rui xue ZHANG Eng Guan TAY School of Mathematics and Computational Sciences Hu’nan First Normal UniversityChangsha 410205P.R.China Mathematics and Mathematics Education National Institute of EducationNanyang Technological University637616Singapore

The skewness of a graph G,denoted by sk(G),is the minimum number of edges in G whose removal results in a planar *** is an important parameter that measures how close a graph is to planarity,and it is complementary,and computationally equivalent,to the Maximum Planar Subgraph *** any connected graph G on p vertices and q edges with girth g,one can easily verify that sk(G)≥π(G),whereπ(G)=[q−g/g−2(p−2)],and the graph G is said to beπ-skew if equality *** concept ofπ-skew was first proposed by *** and ***π-skew graphs with girth 3 are precisely the graphs that contain a triangulation as a spanning *** purpose of this paper is to explore the properties ofπ-skew *** families ofπ-skew graphs are obtained by applying these properties,including join of two graphs,complete multipartite graphs and Cartesian product of two *** also discuss the threshold for the existence of a spanning *** other results some sufficient conditions regarding the regularity and size of a graph,which ensure a spanning triangulation,are given.

关键词： Skewness of graph crossing number of graph Cartesian product join product π-skew

Mechanical design and energy absorption of 3D novel hybrid lattice metamaterials

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Science China(Technological Sciences) 2021年第10期64卷 2220-2228页

作者： ZHANG Peng Biligetu QI DeXing xue rui LIU Kai HUANG ZhiXin WU WenWang LI Ying State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Lightweight Multi-functional Composite Materials and Structures Institute of Advanced Structure TechnologyBeijing Institute of TechnologyBeijing 100081China Department of Engineering Mechanics School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Inner Mongolia First Machinery Group Co.Ltd. Baotou 014000China

In this paper,three-dimensional(3D)novel hybrid lattice structures with exceptional mechanical properties and energy absorbing performances were proposed,and experimental and finite element simulation comparisons were performed to demonstrate their potential in mechanical ***,different types of basic cubic unit cells were designed for constructing three types of novel hybrid metamaterials,in which stepped circulation of different unit cells was conceived to generate architected ***,quasi-static compression experiments and finite element simulations were performed to study the deformation process and failure mechanisms of as-fabricated hybrid *** energy absorption efficiency,specific energy absorption(SEA)indicators,and energy absorption capabilities of different hybrid lattice metamaterials were compared and *** results show that the deformation mechanisms of novel hybrid lattice were beneficial for generating remarkable elevated densification strain,and the energy absorption efficiency can be tailored by altering the types or sizes of basic unit ***-hardening and bilinear features were also obtained.

关键词： hybrid lattice quasi-static compression densification strain energy absorption strain hardening bilinear

LDPC Coded DQPSK Modulation with Iterative Detection Method for Underwater Acoustic Communications

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Journal of Harbin Institute of Technology(New Series) 2013年第5期20卷 25-30页

作者： Fang Fu rui xue Dan-Feng Zhao Xiang-Chao Zhou College of Information and Communication Engineering Harbin Engineering University

Aimed at the conventional serial communication system fails when the channel was frequency-selective,long delay and multi-paths effect,resulting in inter-symbol-interference( ISI),an iterative system for underwater acoustic communication( UWAC) was proposed,which employed iterative differential detection and spread spectrum technique. The proposed scheme adopts π /4-DQPSK soft demodulation to overcome the difficulty of phase ambiguity. For suppression of ISI in UWAC,joint demodulation and decoding iteration was used. The communication scheme has the characteristic of long communication range at low SNR,and the maximum range is up to 100 km. The theoretic analysis and simulation results show that the proposed scheme outperforms traditional serial one. When SNR is- 6 dB,after four joint iterations,compared with serial scheme,BER can decrease from 10- 2to 10- 5.

关键词： Underwater acoustic communications joint demodulation and decoding iterative differential decoding spread spectrum

Super Tough Hydrogels with Self-adaptive Network Facilitated by Liquid Metal

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Chinese Journal of Polymer Science 2023年第6期41卷 866-873,I0006页

作者： Rong-Ze Gao Yu-Xi Li Jian-Hui Yan xue-rui Ma Xu-Ming Xie Key Laboratory of Advanced Materials(MOE) Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Liquid metals(LM)refer to Ga-based alloys with low melting points such as Eutectic GaInSn alloys(EGaInSn),which have excellent fluidity,flexibility and low toxicity at room *** this work,by incorporating EGaInSn into poly(acrylic acid)(PAA)hydrogels as dynamic crosslinkers and effective energy-dissipating units,tough and strong PAA-LM hydrogels are prepared through the interactions between the oxide layers on the surface of LM and carboxyl groups of PAA ***,owing to the fluidity of LM,one LM droplet as a cross-linking point may change its shape or break into more and smaller droplets in the hydrogels upon *** hydrogels with self-adaptive networks can be fabricated by mechanical training through cyclic stretch at a certain ***,the networks of the hydrogels are further homogenized,and the hydrogels are significantly toughened during the training due to the increased cross-linking density from the larger number of smaller LM *** a 5-cycle training at the maximum strain of 500%and 24 h recovering,the tensile strength and initial modulus of the PAA-LM hydrogels can be increased from 355 kPa to 597 kPa and 71 kPa to 166 kPa,respectively,while the elongation at break only decreases from 1491%to 1034%.

关键词： temperature. linking stretching

Visible-to-near-infrared photodetector based on graphene–MoTe2–graphene heterostructure

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Chinese Physics B 2019年第11期28卷 354-359页

作者： rui-xue Hu Xin-Li Ma Chun-Ha An Jing Liu State Key Laboratory of Precision Measurement Technology and Instrument School of Precision Instruments and Opto-electronics EngineeringTianjin UniversityTianjin 300072China

Graphene and transition metal dichalcogenides(TMDs), two-dimensional materials, have been investigated wildely in recent years. As a member of the TMD family, MoTe2 possesses a suitable bandgap of ~1.0 eV for near infrared(NIR)photodetection. Here we stack the MoTe2 flake with two graphene flakes of high carrier mobility to form a graphene–MoTe2–graphene heterostructure. It exhibits high photo-response to a broad spectrum range from 500 nm to 1300 nm. The photoresponsivity is calculated to be 1.6 A/W for the 750-nm light under 2 V/0 V drain–source/gate bias, and 154 mA/W for the 1100-nm light under 0.5 V/60 V drain–source/gate bias. Besides, the polarity of the photocurrent under zero Vds can be efficiently tuned by the back gate voltage to satisfy different applications. Finally, we fabricate a vertical graphene–MoTe2–graphene heterostructure which shows improved photoresponsivity of 3.3 A/W to visible light.

关键词： two-dimensional materials van der Waals heterostructure transition metal dichalcogenides(TMDs) graphene photodetector

Study on Technologies for Information Monitoring and Quick Response of Agricultural Focuses and Significant Events

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Agricultural Sciences in China 2010年第5期9卷 764-770页

作者： ZHAO rui-xue KOU Yuan-tao XIAN Guo-jian MAO Guang-wei Agricultural Information Institute Chinese Acedemy of Agricultural Sciences Beijing 100081 P.R.China

This article analyzed the importance of information monitoring and quick response on agricultural focuses and significant events, proposed the workflow and technical framework for information monitoring and quick response based on modern information technologies, and explained key technologies during implementation and the functional structure for prototype system of the technical support platform.

关键词： agricultural focus significant event information monitoring quick response technical platform

Synthesis of Highly Branched Poly(ε-caprolactone) by Self-condensing Atom Transfer Radical Polymerization of Macroinimers

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Chinese Chemical Letters 2006年第3期17卷 373-376页

作者： rui xue LIU Yan SHI Zhi Feng FU Shu Ke JIAO Key Laboratory of Science and Technology of Controllable Chemical Reactions Ministry of Education Beijing University of Chemical Technology Beijing 100029

Branched poly（ε-capmlactone） was synthesized by self-condensing atom transfer radical polymerization of macroinimer, α-acryloyoxy-ω-2-bromopropionyloxy poly（ε-caprolactone）, which was prepared by enzyme-catalyzed ring-opening polymerization of ε-caprolactone with 2-hydroxylethyl acrylate as initiator and esterification of the ω-hydroxyl group of the obtained poly（ε-caprolactone） by 2-bromopropionyl bromide.

关键词： Self-condensing vinyl polymerization atom transfer radical polymerization branched polymers poly(ε-caprolactone).