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单县表层土壤重金属污染特征、健康风险及溯源解析

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环境科学 2025年第1期46卷 442-452页

作者：赵庆令李清彩马龙贾琛陈娟山东省鲁南地质工程勘察院(山东省地质矿产勘查开发局第二地质大队) 济宁272100 自然资源部采煤沉陷区综合治理与生态修复工程技术创新中心济宁272100 山东农业大学资源与环境学院泰安271018

掌握土壤重金属污染风险特征及定量解析潜在来源,对精准防控、科学管理与安全利用土壤资源具有重要意义.以单县表层土壤为研究对象,采集并测定了330件表层土壤样品As、Cd、Cr、Cu、Hg、Ni、Pb和Zn等8种重金属含量,借助地累积指数和富集... 详细信息

掌握土壤重金属污染风险特征及定量解析潜在来源,对精准防控、科学管理与安全利用土壤资源具有重要意义.以单县表层土壤为研究对象,采集并测定了330件表层土壤样品As、Cd、Cr、Cu、Hg、Ni、Pb和Zn等8种重金属含量,借助地累积指数和富集指数评价了重金属污染程度,利用生态环境部指定的健康风险模型评价了重金属所产生的致癌风险和非致癌风险,运用绝对主成分得分-多元线性回归模型(APCS-MLR)定量解析了表层土壤中重金属的来源.结果表明,单县表层土壤样品中8种重金属的平均值均低于菏泽市表层土壤背景值和国家农用地土壤污染风险筛选值,Hg含量的变异系数达40.26%,其他7种元素含量的变异系数均低于15.2%;经Igeo和EF评价,仅Hg元素约5%的样点为轻微污染,其他7种重金属均为无污染或轻微污染状态;表层土壤中As对成人及儿童的致癌风险和非致癌风险为可耐受水平,其他7种重金属对成人及儿童的致癌风险和非致癌风险均可忽略;表层土壤中Cd、Cu、Zn、Ni和As的主要物质来源为自然背景源,Cr和Hg的主要物质来源分别为农业养殖源和工业燃煤源,Pb的主要污染来源包括其他未知源和自然背景源,自然背景源、农业养殖源、工业燃煤源和其他未知源平均贡献率分别为51.69%、27.18%、6.83%和14.31%,说明单县表层土壤中重金属来源主要为自然背景源,其次为农业养殖源.

关键词：重金属(HMs) 地累积指数富集指数健康风险源解析

算法的“武器化”:计算政治时代被嵌入的安全风险

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东北亚论坛 2025年第1期34卷 44-64,127,128页

作者：董青岭关意为对外经济贸易大学国际关系学院对外经济贸易大学计算社会科学实验室北京100029

当前,由于算法技术的进步,人类社会正在迎来全面智能化转型。作为数智社会运行的底层逻辑,算法重构了权力的物质基础,形成了规定权力运行的权力,创造了新的权力主体,引发了权力结构的动态调整,因而成为了一种“元权力”。在此情形下,作... 详细信息

当前,由于算法技术的进步,人类社会正在迎来全面智能化转型。作为数智社会运行的底层逻辑,算法重构了权力的物质基础,形成了规定权力运行的权力,创造了新的权力主体,引发了权力结构的动态调整,因而成为了一种“元权力”。在此情形下,作为更高级别的权力形式,算法日渐频繁地被大国用作权力竞争武器。简单来说,“算法武器化”指的是行为体有目的、有组织和有意识地运用算法获取权力,以此影响他者行为、打击竞争对手、获取利益或保障安全,最终实现政治目标。在伊朗“推特革命”和美国涉TikTok法案事例中,美国政府展现出将算法“武器化”运用的强烈意愿,试图以算法为抓手、以计算思维为指导遏制竞争对手,塑造霸权优势。在美国决策者看来,算法不仅具有操纵公众认知、干预政治进程和煽动军事对抗的强大功能,而且具有改变经济格局,塑造社会发展形态的巨大潜力。在此背景下,算法逐渐被用作综合国力竞争武器、社会规则竞争武器、前沿阵地争夺武器和权力博弈武器,催生出以算法全域渗透为特征的复杂安全风险。

关键词：算法武器化元权力算法黑箱算法规则新质生产力

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

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

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

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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青钱柳叶中1个新的四氢萘酮苷类化合物

中国中药杂志 2025年第1期50卷 146-151页

作者：郭婷思黄沁胡琪琪黄费炳谢青玲袁汉文王炜翦雨青湖南中医药大学中医药民族医药国际联合实验室湖南长沙410208

运用硅胶、C_(18)反相硅胶、Sephadex LH-20凝胶及半制备型高效液相等色谱技术对青钱柳Cyclocarya paliurus叶中的化学成分进行分离和纯化,通过UV、IR、NMR、MS、计算ECD以及文献数据对比等多种方法共鉴定出6个化合物,分别为cyclopalosi... 详细信息

运用硅胶、C_(18)反相硅胶、Sephadex LH-20凝胶及半制备型高效液相等色谱技术对青钱柳Cyclocarya paliurus叶中的化学成分进行分离和纯化,通过UV、IR、NMR、MS、计算ECD以及文献数据对比等多种方法共鉴定出6个化合物,分别为cyclopaloside D(1)、boscialin(2)、(5R,6S)-6-hydroxy-6-[(E)-3-hydroxybut-1-enyl]-1,1,5-trimethylcyclohexanone(3)、3S,5R-dihydroxy-6R,7-megastigmadien-9-one(4)、3S,5R-dihydroxy-6S,7-megastigmadien-9-one(5)、gingerglycolipid A(6)。其中化合物1为新的四氢萘酮苷类化合物,化合物2~6均为首次从青钱柳叶中分离得到。此外,化合物1表现出较好的抗氧化活性,其对DPPH和ABTS自由基清除活性的IC_(50)分别为(454.20±31.81)、(881.82±42.31)μmol·L^(-1)。

关键词：青钱柳叶化学成分四氢萘酮苷抗氧化活性

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

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)