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Microstructural evolution of a steam-turbine rotor subjected to a water-quenching process: numerical simulation and experimental verification

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Advances in Manufacturing 2019年第1期7卷 84-104页

作者： Chuan Wu qing-ling Meng National-Local Joint Engineering Laboratory of Intelligent Manufacturing Oriented Automobile Die & Mould College of Mechanical Engineering Tianjin University of Technology and Education Tianjin 300222 People's Republic of China College of Civil Engineering Tianjin University Tianjin 300072 People's Republic of China

Cr-Ni-Mo-V steam-turbine rotors have been widely used as key components in power plants. In this study, a coupled thermomechano-metallurgical model was proposed to simulate the phase transformation and transformation-induced plasticity (TRIP) of a 30Cr2Ni4MoV steam-turbine rotor during a water-quenching process, which was solved using a user defined material mechanical behavior (UMAT) subroutine in ABAQUS. The thermal dilation, heat generation from plastic work, transformation latent heat, phase transformation kinetics, and TRIP were considered in the model. The thermomechanical portion of the model was used to predict the evolution of temperature, strain, and residual stress in the rotor. The phase transformation that occurred during the quenching process was considered. Constitutive models of phase transformations (austenite to pearlite, austenite to bainite, and austenite to martensite) and TRIP were developed. Experimental data were adopted and compared with the predicted results to verify the accuracy of the model. This demonstrates that the model is reliable and accurate. Then, the model was utilized to predict the temperature variation, dimensional change, minimum austenitization time, residual stress, TRIP, and volume fractions of each phase. It is concluded that this model can be a useful computational tool in the design of heat-treatment routines of steam-turbine rotors.

关键词： Thermomechano-metallurgical model user defined material mechanical behavior (UMAT) subroutine Microstructural evolution Transformation-induced plasticity (TRIP)- Residual stress

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Pressure and velocity cross-spectrum of normal modes in low-frequency acoustic vector field of shallow water and its application

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Journal of Systems Engineering and Electronics 2015年第2期26卷 241-249页

作者： Yun Yu qing ling Jiang Xu Naval Academy of Armament

The pressure and horizontal particle velocity combined descriptions in the very low frequency acoustic field of shallow wa- ter integrated with the concept of effective depth of Pekeris wave- guide is proposed, especially the active component of the pressure and horizontal particle velocity cross-spectrum, also called ho- rizontal complex cross acoustic intensity, when only two normal modes are trapped in the waveguide. Both the approximate theo- retic analysis and the numerical results show that the sign of the horizontal complex cross acoustic intensity active component is independent of the range when vertically deployed receiving dual sensors are placed in appropriate depths, the sum of which is equal to the waveguide effective depth, so it can be used to tell whether the sound source is near the surface or underwater; while the range rate is expected to be measured by utilizing the sign distribution characteristic of the reactive component. The further robustness analysis of the depth classification algorithm shows that the existence of shear waves in semi infinite basement and the change of acoustic velocity profiles have few effects on the application of this method, and the seabed attenuation will limit the detection range, but the algorithm still has a good robustness in the valid detection range.

关键词： low frequency acoustic vector field effective depth complex cross acoustic intensity active component target depth classificatio

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Adsorption mechanism of different coal ranks under variable temperature and pressure conditions

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Journal of China University of Mining and Technology 2008年第3期18卷 395-400页

作者： ZHANG qing-ling Xi＇ an Branch of China Coal Research Institute Xi＇ an Shaanxi 710054 China

Variable temperature and pressure adsorption tests were conducted on four coal samples with different coal ranks, under simulated temperatures and pressures corresponding to coal reservoirs at different depths. The regularity of the variation in the amounts of adsorption by coals under variable temperature and pressure and 30 ℃ isothermal conditions are compared and the adsorption characteristics of coal under the composite effect of temperature and pressure were obtained. The adsorption test and data processing method of coal under variable temperature and pressure are presented and the effect of the mechanism of temperature and pressure on the adsorption capacity of coal has been studied. The research results are of significant importance in the investigation of coalbed methane storage mechanism and for the prediction of the amounts of coalbed methane at various depths.

关键词： coal variable temperature and pressure test adsorotion characteristics

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Current advances in genome sequencing of common wheat and its ancestral species

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The Crop Journal 2018年第1期6卷 15-21页

作者： Xiaoli Shi Hong-qing ling State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental Biology Chinese Academy of Sciences College of Life Sciences University of Chinese Academy of Sciences

Common wheat is an important and widely cultivated food crop throughout the *** progress has been made in regard to wheat genome sequencing in the last *** from the sequencing of single chromosomes/chromosome arms whole genome sequences of common wheat and its diploid and tetraploid ancestors have been decoded along with the development of sequencing and assembling technologies. In this review, we give a brief summary on international progress in wheat genome sequencing, and mainly focus on reviewing the effort and contributions made by Chinese scientists.

关键词： Genome sequencing Diploid wheat Tetraploid wheat Triticum aestivum

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Decentralized and Privacy-Preserving Low-Rank Matrix Completion

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Journal of the Operations Research Society of China 2015年第2期3卷 189-205页

作者： An-Ya Lin qing ling Department of Automation University of Science and Technology of ChinaHefeiChina

In this paper,we propose a decentralized algorithm to solve the low-rank matrix completion problem and analyze its privacy-preserving *** that we want to recover a low-rank matrix D=[D1,D2,・・・,DL]from a subset of its *** a network composed of L agents,each agent i observes some entries of *** factorize the unknown matrix D as the product of a public matrix X which is common to all agents and a private matrix Y=[Y1,Y2,・・・,YL]of which Yi is held by agent i *** agent i updates Yi and its local estimate of X,denoted by X(i),in an alternating *** exchanging information with neighbors,all the agents move toward a consensus on the estimates X(i).Once the consensus is(nearly)reached throughout the network,each agent i recovers Di=X(i)Yi,thus D is *** this progress,communication through the network may disclose sensitive information about the data matrices Di to a malicious *** prove that in the proposed algorithm,D-LMaFit,if the network topology is well designed,the malicious agent is unable to reconstruct the sensitive information from others.

关键词： Decentralized algorithm Matrix completion Privacy-preserving

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FOLMS-AMDCNet:an automatic recognition scheme for multiple-antenna OFDM systems

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Journal of Systems Engineering and Electronics 2023年第2期34卷 307-323页

作者： ZHANG Yuyuan YAN Wenjun ZHANG Limin ling qing Academy of Aeronautical Operations Service Naval Aviation UniversityYantai 264001China

The existing recognition algorithms of space-time block code(STBC)for multi-antenna(MA)orthogonal frequencydivision multiplexing(OFDM)systems use feature extraction and hypothesis testing to identify the signal types in a complex communication ***,owing to the restrictions on the prior information and channel conditions,these existing algorithms cannot perform well under strong interference and noncooperative communication *** overcome these defects,this study introduces deep learning into the STBCOFDM signal recognition field and proposes a recognition method based on the fourth-order lag moment spectrum(FOLMS)and attention-guided multi-scale dilated convolution network(AMDCNet).The fourth-order lag moment vectors of the received signals are calculated,and vectors are stitched to form two-dimensional FOLMS,which is used as the input of the deep learning-based ***,the multi-scale dilated convolution is used to extract the details of images at different scales,and a convolutional block attention module(CBAM)is introduced to construct the attention-guided multi-scale dilated convolution module(AMDCM)to make the network be more focused on the target area and obtian the multi-scale guided ***,the concatenate fusion,residual block and fully-connected layers are applied to acquire the STBC-OFDM signal *** experiments show that the average recognition probability of the proposed method at−12 dB is higher than 98%.Compared with the existing algorithms,the recognition performance of the proposed method is significantly improved and has good adaptability to environments with strong *** addition,the proposed deep learning-based model can directly identify the pre-processed FOLMS samples without a priori information on channel and noise,which is more suitable for non-cooperative communication systems than the existing algorithms.

关键词： blind signal identification(BSI) space-time block code(STBC) orthogonal frequency-division multiplexing(OFDM) deep learning fourth-order lag moment spectrum(FOLMS)

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A Novel Photoproduct of Thymine in Phosphate-buffered Saline under Far UV Irradiation

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Chinese Chemical Letters 2003年第12期14卷 1233-1235页

作者： Feng LIN qing ling MA Department of Chemistry Xi-xi CampusZhejiang UniversityHangzhou 310028

The photolysis of thymine in phosphate-buffered saline (PBS, pH 8.0) under the irradiation of medium pressure mercury lamp (MPML) produces a novel compound C5H7N2O6P. The composition and structure of the compound hav... 详细信息

关键词： UV photolysis thymine phosphate-buffered saline (PBS).

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DFT Study on Molecule C_(20)H_(10): Five Carbon-carbon Single Bonds Linking Two Pentaprismane Cages

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Chinese Journal of Structural Chemistry 2005年第7期24卷 745-750,735页

作者： LIUFeng-ling GUOWei-ling ZHAIYu-qing FENGShuai DepartmentofChemistry ShandongNormalUniversityJinan250014China

Using geometry optimization and DFT method at the B3LYP/6-31G* level for C20H10, an equilibrium geometry is identified to have the form of polyhedral hydrocarbon with five carbon-carbon single bonds linking two pentaprismane cages. Thus, C20H10 is a tri-cage molecule with three pentaprismane cages. Vibrational frequencies and infrared spectrum are computed at the same level. The heat of formation for this molecule has also been estimated in this paper.

关键词： tri-cage molecule C20H10 B3LYP/6-31G* vibrational frequency heat of formation

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Iodopentafluorosulfanylation of [1.1.1]propellane and further functionalizations

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Science China Chemistry 2023年第10期66卷 2871-2877页

作者： Xin Zhao Jia-Yi Shou Feng-ling qing Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China

Pentafluorosulfanylated(SF_(5^(-))) aromatics have shown great potential in drugs, and the bioisosteric replacement of aromatic ring with bicyclo[1.1.1]pentane(BCP) unit has attracted considerable attention recently. Consequently, pentafluorosulfanylated bicyclo[1.1.1]pentanes(SF_(5^(-))BCPs) should have application in the realm of drug discovery. In this study, a one-pot iodopentafluorosulfanylation of [1.1.1]propellane with SF_(5)Cl and CH_(2)I_(2)for the practical synthesis of iodopentafluorosulfanylated bicyclo[1.1.1]pentane(SF_(5^(-))BCP-I) was developed. SF_(5^(-))BCP-I was the first example of SF_(5^(-))BCPs that could be transformed. The first general method to access SF_(5^(-))substituted bicyclo[1.1.1]pentane derivatives was demonstrated through photoredox-catalyzed radical addition of SF_(5^(-))BCP-I to alkenes and alkynes.

关键词： pentafluorosulfanyl bicyclo[1.1.1]pentane(BCP) bioisosteres photoredox radical

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Hierarchical space–time block codes signals classification using higher order cumulants

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Chinese Journal of Aeronautics 2016年第3期29卷 754-762页

作者： ling qing Zhang Limin Yan Wenjun Kong Dongming Istitute of Information Fusion Naval Aeronautical and Astronautical University Yantai 264001China Equipment of Navy Talyuan 030027China

An efficient method for blind classification of space time block codes （STBCs） based on fourth-order cumulants is proposed for a single receiver antenna. This paper presents a model of received STBCs signals in multiple input single output （MISO） communication systems and applies the characteristics of coding matrices to derive analytical expressions for the fourth-order cumu- lants to be used as the basis of an algorithm. The fourth-order cumulants at various delay vectors present non-null values that depend on the transmitted STBCs. Tests of nullity are accomplished by hypothesis testing. The proposed algorithm avoids the need for a priori information of modulation scheme, channel coefficients, and noise power. Consequently, it is well suited for non-cooperative scenarios. Simulations show that this method performs well even at low signal-to-noise ratios （SNRs）.

关键词： Blind classification Fourth-order cumulants Multiple input single output Non-cooperative context STBCs

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