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Agricultural Sciences in China 2009年第5期8卷 521-528页

作者： cheng li-bao li Shu-yan HE Guang-yuan China-UK HUST-RRes Genetic Engineering and Genomics Joint Laboratory/Key Laboratory of Molecular Biophysics Ministry of Education/College of Life Science and Technology Huazhong University of Science and Technology Wuhan 430074 P.R. China life Science and Technique College Xiaogan University Xiaogan 432000 P.R.China

Germination of soybean seed is always arrested by chilling imbibitional stress, and this phenomenon is widespread in the plant seed kingdom, but has not been studied at molecular level. In this experiment, cDNA-amplified fragment length polymorphism （cDNA-AFLP） technique was applied to isolate genes relevant to chilling stress （4℃） during soybean seed imbibition. Eight genes were found to be up-regulated and two were down-regulated during chilling stress respectively. Four up-regulated genes were selected to analyze the expression profiles during imbibition under chilling condition. It was demonstrated that the four genes were induced significantly by 4℃ for 24 h, and decreased when the temperature was shifted from 4 to 22℃. GMCHl, a highly chilling stress-induced gene which responded to abscisic acid （ABA）, polyethylene glycol （PEG） and NaCl, showed great stress-resistance according to published reports. Cos78 was identified to be induced by PEG. However, Cos66 and Cos36 transcription showed no change to ABA, PEG, and NaCl. From the characteristic of genes isolated from the embryonic axis, we concluded that soybean seeds have different pathways to adapt to various biotic and abiotic stresses by regulating many signal transduction pathways.

关键词： soybean germination imbibition stress cDNA-AFLP

Binding and Adsorption Energies of Heavy Metal Ions with Hapli-Udic Argosol and Ferri-Udic Argosol Particles

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Pedosphere 2007年第6期17卷 688-696页

作者： WANG Yu-Jun li cheng-bao WANG Wei ZHOU Dong-Mei XU Ren-Kou Institute of Soil Science the Chinese Academy of Sciences P.O. Box 821 Nanjing 210008 （China） College of Resource and Environment Nanjing Agricultural University Nanjing 210095 （China）

Gibbs free binding energy and adsorption energy between cations and charged soil particles were used to evaluate the interactions between ions and soil particles. The distribution of Gibbs free adsorption energies could not be determined experimentally before the development of Wien effect measurements in dilute soil suspensions. In the current study, energy relationships between heavy metal ions and particles of Hapli-Udic Argosol （Alfisol） and Ferri-Udic Argosol were inferred from Wien effect measurements in dilute suspensions of homoionic soil particles （〈 2 μm） of the two soils, which were saturated with ions of five heavy metals, in deionized water. The mean Gibbs free binding energies of the heavy metal ions with Hapli-Udic Argosol and Ferri-Udic Argosol particles diminished in the order of Pb^2＋〉 Cd^2＋〉 Cu^2＋〉 Zn^2＋〉 Cr^3＋, where the range of binding energies for Hapli-Udic Argosol （7.25-9.32 kJ mol^-1） was similar to that for Ferri-Udic Argosol （7.43-9.35 kJ mol^-1）. The electrical field-dependent mean Gibbs free adsorption energies of these heavy metal ions for Hapli-Udic Argosol and for Ferri-Udic Argosol descended in the order： Cu^2＋〉 Cd2^＋〉 Pb^2＋〉 Zn^2＋〉 Cr^3＋, and Cd^2＋〉 Cu^2＋〉 Pb^2＋〉 Zn^2＋〉 Cr^3＋, respectively. The mean Gibbs free adsorption energies of Cu^2＋, Zn^2＋, Cd^2＋, Pb^2＋, and Cr^3＋ at a field strength of 200 kV cm^-1, for example, were in the range of 0.8-3.2 kJ mo1^-1 for the two soils.

关键词： adsorption energy Argosol binding energy heavy metal ion Wien effect

Interactions of Heavy Metal Ions with Paddy Soils as Inferred from Wien Effect Measurements in Dilute Suspensions

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Pedosphere 2006年第6期16卷 718-725页

作者： JIANG Jun li cheng-bao ZHAO An-Zhen XU Ren-Kou WANG Yu-Jun S. P. FRIEDMAN Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China Institute of Soil Water and Environmental Sciences Agricultural Research Organization Voleani Center Bet Dagan 50250 Israel

Interactions of three heavy metal ions, Cu^2＋, Cd^2＋, and Pb^2＋, and, for comparison, Na^＋ with electrodialytic clay fractions （less than 2μm in diameter） of four paddy soils as well as a yellow-brown soil as a control soil were evaluated based on measurements of the Wien effect in dilute suspensions with a clay concentration of 10 g kg^-1 in four nitrate solutions of 2 × 10^-4/z mol L^-1, where z is the cation valence, and a nitric acid solution of 3 × 10^-5 mol L^-1, Field strengths ranging from 15 to 230 kV cm^-1 were applied for measuring the electrical conductivities （ECs） of the suspensions. The mean free binding energies between the various cations and all of the soils determined from exchange equilibrium increased in the order： Na^＋〈 Cd^2＋〈 Cu^2＋〈 Pb^2＋. In general, the ECs of the suspensions in the sodium nitrate solution were smaller than those of the suspensions in the heavy metal solutions because of the lower electrophoretic mobility of sodium compared to the divalent cations. In terms of relative electrical conductivity-field strength relationships, relative electrical conductivity （REC） of suspensions containing various cations at field strengths larger than about 50 kV cm^-1 were in the descending order： Na^＋〉 Cu^2＋〉 Cd^2＋〉 Pb^2＋ for all tested soils. A characteristic parameter of the REC-field strength curves, AREC200, REC at a field strength of 200 kV cm^-1 minus that at the local minimum of the concave segment of the REC-field strength curves, characterized the strength of adsorption of the cations stripped off by the applied strong electrical field, and for all soils the values of AREC200 were generally in the order： Na^＋〈 Cu^2＋ ≤ Cd^2＋〈 Pb^2＋.

关键词： binding energy electrical conductivity field strength heavy metal ions paddy soils

Control of Corner Separation for a linear Compressor Cascade via Bionic Slanting Riblets at the Endwall

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Journal of Thermal Science 2025年第1期34卷 129-144页

作者： ZHANG Peng li Yonghong cheng Rixin Key Laboratory of Civil Aircraft Airworthiness Technology Civil Aviation University of ChinaTianjin 300300China College of Aeronautical Engineering Civil Aviation University of ChinaTianjin 300300China

A new passive control approach,utilizing bionic slanting riblets,is employed to mitigate the flow close to the blade endwall in a linear cascade,and its effectiveness and mechanism in controlling corner separation are investigated through numerical *** slanting riblets are positioned at the endwall upstream of the cascade channel,and the influence of riblet height,yaw angle and relative position on the control of corner separation is *** findings indicate that the application of slanting riblets can efficiently counteract corner separation across the stable operational ***,the introduction of riblets with a height of merely 0.1 times the boundary layer thickness results in a significant reduction in total pressure loss by up to 14.53%,while simultaneously enhancing the static pressure coefficient by 21.74%.Flow analysis reveals that minute vortices produced within the riblet channels tend to coalesce,forming a potent large-scale vortex near the boundary layer's base *** phenomenon results in reduced additional losses compared to conventional vortex ***,the induced vortex promotes enhanced mixing between the mainstream flow and boundary layer,inhibiting the lateral displacement of low-energy fluids within the endwall boundary ***,this delays the onset of separation vortex formation and eliminates vortex rings in the corner region,ultimately enhancing the aerodynamic efficiency of the cascade.

关键词： corner separation compressor cascade slanting riblets additional losses vortex generator

Recent progress in flexible sensors based on 2D materials

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Journal of Semiconductors 2025年第1期46卷 130-142页

作者： Xiang li Guancheng Wu Caofeng Pan Rongrong bao School of Physics Beihang UniversityBeijing 100191China Institute of Atomic Manufacturing Beihang UniversityBeijing 100191China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijing 100049China

With the rapid development of the internet of things(IoT)and wearable electronics,the role of flexible sensors is becoming increasingly irreplaceable,due to their ability to process and convert information ***-dimensional(2D)materials have been widely welcomed by researchers as sensitive layers,which broadens the range and application of flexible sensors due to the advantages of their large specific surface area,tunable energy bands,controllable thickness at the atomic level,stable mechanical properties,and excellent optoelectronic *** review focuses on five different types of 2D materials for monitoring pressure,humidity,sound,gas,and so on,to realize the recognition and conversion of human body and environmental ***,the main problems and possible solutions of flexible sensors based on 2D materials as sensitive layers are summarized.

关键词： 2D materials flexible sensors layered structure solution method

Spatial Pattern and Influencing Factors of China’s Digital Trade Resilience under the Impact of Trade Frictions

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Chinese Geographical Science 2025年第1期35卷 203-216页

作者： li Chunli ZHU Huayou bao Weiping QIN Manman School of E-Commerce Yiwu Industrial and Commercial CollegeJinhua 322000China College of Economics and Management Zhejiang Normal UniversityJinhua 321004China

In the era of the digital economy,digital trade has demonstrated strong vitality,becoming a crucial driving force for the highquality development of national and regional ***,understanding the resilience of digital trade in the face of external crises is an important *** the backdrop of Sino-US trade friction,this paper constructs a resilience index system for digital *** utilizes entropy method,kernel density estimation,and ArcGIS mapping to calculate and visually analyze the resilience of China’s digital trade from 2017 to ***,a Tobit model is constructed to explore the main influencing factors of digital trade resilience *** research findings indicate:1)temporally,during the period of Sino-US trade friction,China’s digital trade resilience shows an overall upward trend,but there are regional differences in resilience levels across the country,with a severe polarization phenomenon.2)Spatially,high resilience is observed in the eastern and central regions of China,while the western and northeastern regions exhibit low resilience.3)From a dimensional perspective,the resistance of digital trade resilience displays a spatial distribution of high values in the east and low values in the *** recovery force is aggregated along coastal areas,and the renewal force tends to aggregate along the eastern coastline.4)Factors such as economic scale,industrial structure,urbanization rate,government fiscal expenditure,and technological talents significantly promote the enhancement of digital trade *** study reveals the dynamic characteristics and influencing factors of digital trade resilience in responding to external shocks,providing theoretical basis and policy suggestions for enhancing digital trade resilience,and promoting high-quality economic development in China.

关键词： digital trade resilience trade friction resilience pattern resilience factors China

同方期刊数据库

Quantum public-key crypto via EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 54-59页

作者： Xiang-Qun Fu Hong-Wei li Jian-Hong Shi Tan li Wan-Su bao Henan Key Laboratory of Quantum Information and Cryptography Information Engineering UniversityZhengzhou 450004China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China

With the development of quantum computing technology,quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key *** paper designs a quantum trapdoor one-way function via EPR pairs and quantum *** on this,a new quantum public-key cryptosystem is presented,which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext *** with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition,which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs

Theoretical calculation on degradation mechanism of novel copolyesters under CALB enzyme

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Journal of Environmental Sciences 2025年第3期149卷 242-253页

作者： Yuanyang Ren Zhiwen cheng Luwei cheng Yawei liu Mingyue li Tao Yuan Zhemin Shen School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants Shanghai 200240China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Poly(butylene succinate-co-furandicarboxylate)(PBSF)and poly(butylene adipateco-furandicarboxylate)(PBAF)are novel furandicarboxylic acid-based biodegradable copolyesters with great potential to replace fossil-derived terephthalic acid-based copolyesters such as poly(butylene succinate-co-terephthalate)(PBST)and poly(butylene adipate-co-terephthalate)(PBAT).In this study,quantum chemistry techniques after molecular dynamics simulations are employed to investigate the degradationmechanism of PBSF and PBAF catalyzed by Candida antarctica lipase B(CALB).Computational analysis indicates that the catalytic reaction follows a four-step mechanism resembling the ping-pong bibi mechanism,with the initial two steps being acylation reactions and the subsequent two being hydrolysis ***,the first step of the hydrolysis is identified as the rate-determining ***,by introducing single-point mutations to expand the substrate entrance tunnel,the catalytic distance of the first acylation step ***,energy barrier of the rate-determining step is decreased in the PBSF system by site-directed mutations on key residues increasing hydrophobicity of the enzyme’s active *** study unprecedently show the substrate binding pocket and hydrophobicity of the enzyme’s active site have the potential to be engineered to enhance the degradation of copolyesters catalyzed by CALB.

关键词： Poly(butylene succinate-co-furandicarboxylate) Poly(butylene adipate-co-furandicarboxylate) Candida antarctica lipase B Degradation mechanism Site-directed mutations

A logistic-Lasso-regression-based seismic fragility analysis method for electrical equipment considering structural and seismic parameter uncertainty

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 169-186页

作者： Cui Jiawei Che Ailan li Sheng cheng Yongfeng Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education School of Civil EngineeringHarbin Institute of TechnologyHarbin 150094China School of Ocean and Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China China Electric Power Research Institute Beijing 100055China

Damage to electrical equipment in an earthquake can lead to power outage of power *** fragility analysis is a common method to assess the seismic reliability of electrical *** further guarantee the efficiency of analysis,multi-source uncertainties including the structure itself and seismic excitation need to be considered.A method for seismic fragility analysis that reflects structural and seismic parameter uncertainty was developed in this *** proposed method used a random sampling method based on Latin hypercube sampling(LHS)to account for the structure parameter uncertainty and the group structure characteristics of electrical ***,logistic Lasso regression(LLR)was used to find the seismic fragility surface based on double ground motion intensity measures(IM).The seismic fragility based on the finite element model of an±1000 kV main transformer(UHVMT)was analyzed using the proposed *** results show that the seismic fragility function obtained by this method can be used to construct the relationship between the uncertainty parameters and the failure *** seismic fragility surface did not only provide the probabilities of seismic damage states under different IMs,but also had better stability than the fragility ***,the sensitivity analysis of the structural parameters revealed that the elastic module of the bushing and the height of the high-voltage bushing may have a greater influence.

关键词： seismic fragility uncertainty logistic lasso regression ±1000 kV main transformer sensitivity analysis

Wien Effect Characterization of Interactions Between Ions and Charged Sites on Clay Surfaces of Variable-Charge Soils

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Pedosphere 2009年第5期19卷 545-553页

作者： ZHU Hao-Wen WANG Yu-Jun ZHOU Jun JIANG Jun li cheng-bao ZHOU Dong-Mei S. P. FRIEDMAN Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) Institute of Soil Water and Environmental Sciences Agricultural Research Organization the Volcani Center Bet Dagan 50250 (Israel)

To investigate the interactions of oppositely charged sites on the surfaces of variable-charge soil particles with cations and anions, and to evaluate the mean Gibbs free binding and adsorption energies of various cations on particles of red soil and latosol, clay fractions smaller than 2 μm were separated from samples of the two variable-charge soils. Ferric oxides were removed from part of the clay fractions, which were then saturated with various chlorides （NaC1, KCl, CaCl2, CdCl2 or LaCl3）. Electrical conductivities （EC） of dilute suspensions of the original and of the iron oxides-free clay fractions in deionized water were measured with the SHP-2 short high-voltage pulse apparatus, which enables measurement of the Wien effect at field strengths （E） from 14 to 250 kV cm^-1. The Wien effect （EC-E） curves revealed EC increases of red soil suspensions between 14 and 200 kV cm^-1, of 8.3, 8.4, 12.1, 5.9, and 1.2 μS cm^-1 for NaCl, KCl, CaCl2, CdCl2, and LaCl3, respectively, reflecting the differing interactions with the various cations and chloride. The EC increments with the iron-free red soil suspensions were higher, being 29.7, 17.2, and 15.3 μS cm^-1 for NaCl, CaCl2, and CdCl2, respectively. In the natural latosol suspensions the EC increments were practically zero, whereas in the iron-free fractions there were significant EC increments of 10.3, 5.7, 5.0, and 1.6μS cm^-1 for NaCl, CaCl2, CdCl2, and LaCl3, respectively.

关键词： electrical conductivity field strength iron oxide overlapping ζ potential