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基于水自由基阳离子快速检测甲醇和乙醇

质谱学报 2024年第1期45卷 123-130,I0004页

作者：段敏敏张小平胡平花袁艳春张兴磊陈焕文东华理工大学江西省质谱科学与仪器重点实验室江西南昌330013 江西中医药大学药学院江西南昌330004

本文采用常压电晕放电电离质谱技术,开发了一种快速检测甲醇和乙醇含量的方法。基于水自由基阳离子分别与甲醇和乙醇相互作用形成相应的水自由基阳离子复合物[CH_(3)OH+H_(2)O]^(+·)(m/z 50)和[CH_(3)CH_(2)OH+H_(2)O]^(+·)(m/z 64),... 详细信息

本文采用常压电晕放电电离质谱技术,开发了一种快速检测甲醇和乙醇含量的方法。基于水自由基阳离子分别与甲醇和乙醇相互作用形成相应的水自由基阳离子复合物[CH_(3)OH+H_(2)O]^(+·)(m/z 50)和[CH_(3)CH_(2)OH+H_(2)O]^(+·)(m/z 64),实现了不同种类酒精饮料中甲醇和乙醇的直接快速定性与定量分析。结果表明,甲醇和乙醇的检出限分别为0.011、0.004 mg/L,定量限分别为0.038、0.014 mg/L。该方法无需样品前处理、操作简单、分析速度快,适合含水体系的检测,对复杂体系中甲醇和乙醇的定量分析具有指导意义。

关键词：水自由基阳离子甲醇乙醇含酒饮料常压电晕放电质谱

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Microstructure of a Ti–50wt% Ta alloy produced via laser powder bed fusion

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Acta Metallurgica Sinica(English Letters) 2020年第7期33卷 981-990页

作者： lei-lei xing Cong-Cong Zhao Hao Chen Zhi-Jian Shen Wei Liu School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Jihua Laboratory 13th FloorChengye buildingNanping West Road No.13GuichengNanhai districtFoshan cityGuangdong province 528000China Arrhenius Laboratory Department of Materials and Environmental ChemistryStockholm University10691StockholmSweden

Ti-Ta alloys have been widely studied for biomedical applications due to their high biocompatibility and corrosion *** this work,nearly fully dense and in situ alloyed Ti-50 wt% Ta samples were fabricated by the laser powder bed fusion(LPBF) of mechanically mixed *** increased exposure time,and thereby increased laser energy density,insoluble Ta particles were almost dissolved,and a Ti-50 wt% Ta alloy was *** and dendritic structures were formed due to constitutional undercooling,which was caused by the high cooling rate of LPBF *** retained βphases and α " phases were observed in the LPBFed Ti-50 wt% Ta *** α" phase was found at the boundary of the cellular structures,where the tantalum content was not high enough to suppress the bcc lattice transition completely but could suppress the β phase→α’ phase transition.

关键词： alloy Microstructure corrosion

生物菌剂对青枯病防控效果及其影响因素的优化

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植物营养与肥料学报 2024年第4期30卷 655-665,I0001,I0002页

作者：胡星磊白鸽邱巍袁军秦华赵梦丽徐秋芳浙江省亚热带森林培育国家重点实验室/浙江农林大学浙江杭州311300 浙江农林大学环境与资源学院/碳中和学院浙江杭州311300 南京农业大学资源与环境科学学院江苏南京210095

[目的]由茄科劳尔氏菌引起的青枯病是一种普遍的细菌性土传病害,严重威胁多种经济作物的生产。青枯病主要采用生物技术防治,但由于施用方法以及生防菌株较为多元,生防效果差异较大。因此,我们研究了生物菌剂对青枯病发病率的防控效果及... 详细信息

[目的]由茄科劳尔氏菌引起的青枯病是一种普遍的细菌性土传病害,严重威胁多种经济作物的生产。青枯病主要采用生物技术防治,但由于施用方法以及生防菌株较为多元,生防效果差异较大。因此,我们研究了生物菌剂对青枯病发病率的防控效果及主要影响因素。[方法]基于Web of Science和CNKI数据库,以关键词“青枯病”和“生物菌剂”、“Ralstonia solanacearum”或“Pseudomonas solanacearum”和“Biological bacterium agent”或“Biological bacterium control”进行检索。以具有1个不施生物菌剂对照组,且具有发病率(DI)、发病率均值和样本量为条件进行筛选,共获得113对有效数据。采用meta分析方法评估了生物菌剂的防控效果及主要影响因素。采用Metawin软件中的随机效应模型,以处理组和对照组之间的效应值(effect size, ES)评价因素的效应强弱。[结果]施用生物菌剂后,青枯病发病率从77.35%降至37.13%,防控效率为52.00%。施用模式、土壤中功能微生物与青枯菌数量比、功能微生物种类是影响青枯病防治效果的主要因素。土施、浸根、喷淋和种子处理4种施用方法对青枯病的防控效应值分别为-0.80~-0.61、-1.34~-1.15、-0.96~-0.79和-0.67~-0.49,说明4种施用方法均有显著的防控效果,以浸根法的防控效率最好,其防控效率可达66.72%。施用生物菌剂后的土壤中功能微生物与青枯菌数量比值为1∶1、10∶1、100∶1时,对青枯病均有显著防控效果,以比值为100∶1时的防控效果(63.62%)最为显著。链霉菌对青枯病的防效优于假单胞菌和芽孢杆菌,其防控效率可达74.08%。[结论]生物菌剂对青枯病的防治效果普遍较为显著,采用移栽前浸根,生物菌剂施用量达到土壤中功能微生物数量与青枯菌数量比值为100∶1,选择链霉菌属作为功能菌剂,均可获得较高且稳定的青枯病防控效果。

关键词：青枯病发病率生物菌剂防控效果 meta分析

九州-帕劳海脊南段及邻近海域典型海山形态特征及地质意义

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海洋地质与第四纪地质 2024年第4期44卷 65-77页

作者：刘佳李攀峰邢磊胡邦琦杨慧良赵京涛中国海洋大学海洋地球科学学院青岛266100 中国地质调查局青岛海洋地质研究所青岛266237

对海山形态特征的定量分析与讨论,有助于理解海山的形成与演化,从而进一步了解与海山地貌形态有关的动力作用。基于九州-帕劳海脊南段及邻近海域的高分辨率海底地形和浅地层剖面资料,利用统计学、频谱分析及层序地层学等方法,查明了研究... 详细信息

对海山形态特征的定量分析与讨论,有助于理解海山的形成与演化,从而进一步了解与海山地貌形态有关的动力作用。基于九州-帕劳海脊南段及邻近海域的高分辨率海底地形和浅地层剖面资料,利用统计学、频谱分析及层序地层学等方法,查明了研究区40座海山的形态特征,并对海山的演化过程进行了分析推测,同时指出了海山对底流沉积动力的影响。结果表明,研究区海山平均高度为1374 m,平均体积为100 km3,宽高比为0.21±0.09,平坦度为0.16±0.18;在中央海盆裂谷北侧和九州-帕劳海脊南段海山高度与底面半径具有较好的线性关系,而在中央海盆裂谷南侧相关性较差;中央海盆裂谷南侧海山的宽高比明显大于北侧,可能是由复杂的应力背景和构造机制等因素所导致。总结火山演化的4种生长模型,分析认为研究区海山的形态演化与山顶高度和基底直径成比例增加的火山生长模型基本类似,可能是由于火山间断喷发导致海山顶部与侧翼同时成比例发育。

关键词：成因演化沉积动力海山九州-帕劳海脊

Wigner Function of Density Operator for Negative Binomial Distribution

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Communications in Theoretical Physics 2008年第6期49卷 1453-1456页

作者： XU xing-lei LI Hong-Qi Department of Physics Heze University Heze 274015 China Key Laboratory of Quantum Communication and Calculation Heze University Heze 274015 China

By using the technique of integration within an ordered product （IWOP） of operator we derive Wigner function of density operator for negative binomial distribution of radiation field in the mixed state case, then we derive the Wigner function of squeezed number state, which yields negative binomial distribution by virtue of the entangled state representation and the entangled Wigner operator.

关键词： IWOP Wigner function negative binomial distribution

稀土La对含Cu马氏体不锈钢显微组织与力学性能的影响

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金属热处理 2024年第8期49卷 42-47页

作者：曹悦高雪云王海燕邢磊林鸿亮内蒙古科技大学材料与冶金学院内蒙古包头014010 广东广青金属科技有限公司广东阳江529533

以不含La和含0.012%La的含Cu Cr13马氏体不锈钢为研究对象,对其进行980℃固溶油冷和500℃不同保温时间的时效处理,借助光学显微镜、扫描电镜、EBSD表征,结合力学性能测试,研究了稀土添加对试验钢显微组织和力学性能的影响。结果表明,稀... 详细信息

以不含La和含0.012%La的含Cu Cr13马氏体不锈钢为研究对象,对其进行980℃固溶油冷和500℃不同保温时间的时效处理,借助光学显微镜、扫描电镜、EBSD表征,结合力学性能测试,研究了稀土添加对试验钢显微组织和力学性能的影响。结果表明,稀土La可显著降低不锈钢中δ铁素体体积分数,使淬火马氏体增多,进而增加基体中的位错密度,从而提高油冷后试验钢的硬度和强度。在时效过程中,富Cu颗粒不断析出,在达到时效强化峰阶段可为不锈钢的屈服强度提供贡献约200 MPa,未发现稀土La对富Cu相析出动力学明显的作用行为。同时,由于时效过程中小角度晶界不断减少,大角度晶界增多,使试验钢的塑性显著改善。

关键词： Cr13马氏体不锈钢 La 显微组织析出相力学性能

The Sensitive Properties of Hydrate Reservoirs Based on Seismic Stereoscopic Detection Technology

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Acta Geologica Sinica(English Edition) 2020年第2期94卷 530-544页

作者： LIU Xueqin xing lei QIN Zhiliang LIU Huaishan Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001China Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001China College of Underwater Acoustic Engineering.Harbin Engineering University Harbin 150001China Key Lab of Submarine Geosciences and Prospecting Techniques MOE and College of Marine GeosciencesOcean University of ChinaQingdao 266100China Evaluation and Detection Technology Laboratory of Marine Mineral Resources Qingdao 266100China National Laboratory for Marine Science and Technology Qingdao 266061China

Higher-precision determinations of hydrate reservoirs, hydrate saturation levels and storage estimations are important for guaranteeing the ability to continuously research, develop and utilize natural gas hydrate resources in China. With seismic stereoscopic detection technology, which fully combines the advantages of different seismic detection models, hydrate formation layers can be observed with multiangle, wide-azimuth, wide-band data with a high precision. This technique provides more reliable data for analyzing the distribution characteristics of gas hydrate reservoirs, establishing velocity models, and studying the hydrate-sensitive properties of petrophysical parameters;these data are of great significance for the exploration and development of natural gas hydrate resources. Based on a velocity model obtained from the analysis of horizontal streamer velocity data in the hydrate-bearing area of the Shenhu Sea, this paper uses three VCs(longitudinal spacing of 25 m) and four OBSs(transverse spacing of 200 m) to jointly detect seismic datasets consisting of wave points based on an inversion of traveltime imaging sections. Accordingly, by comparing the differences between the seismic phases in the original data and the forward-modeled seismic phases, multiangle coverage constraint corrections are applied to the initial velocity model, and the initial model is further optimized, thereby improving the imaging quality of the streamer data. Petrophysical elastic parameters are the physical parameters that are most directly and closely related to rock formations and reservoir physical properties. Based on the optimized velocity model, the rock elastic hydrate-sensitive parameters of the hydrate reservoirs in the study area are inverted, and the sensitivities of the petrophysical parameters to natural gas hydrates are investigated. According to an analysis of the inversion results obtained from these sensitive parameters, λρ, Vp and λμ are simultaneously controlled b

关键词： natural gas hydrate stereoscopic detection elastic modulus sensitive parameters

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通感一体化系统波束成形设计

山东工业技术 2024年第1期 107-111页

作者：雷振星张世欣河南新工匠智能系统有限公司河南郑州450018 河南机电职业学院河南郑州451100

本文研究了MIMO通感一体化系统的收发机波束成形,为刻画MIMO通信与雷达的性能折衷关系,建立了通感一体化系统的可达性能区域,并采用连续凸逼近方法求解所提出的非凸约束问题,给出仿真结果验证所提方案的有效性。

关键词：通感一体化波束成形可达性能区域

Tectonics of the Solomon Sea Basin from Vertical Gravity Gradient and Seismic Data

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Acta Geologica Sinica(English Edition) 2023年第2期97卷 610-622页

作者： GONG Wei xing Junhui MENG Qingwei xing lei XU Chong ZHANG Hao Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of Educationand College of Marine GeosciencesOcean University of ChinaQingdaoShandong 266100China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdaoShandong 266237China Chinese Academy of Geological Sciences Beijing 100037China

The Solomon Sea Basin is a Cenozoic back-arc spreading basin within the convergence system of the Pacific and Indo-Australian *** the background of subduction polarity reversal,the current Solomon Sea Basin gradually formed a rhombic morphology with the subduction of the basin along the New Britain Trench and the Trobriand *** analyzing the vertical gravity gradient,natural earthquake and seismic reflection data,this study determines the structural characteristics of the Solomon Sea *** was found that the tectonics of the basin are characterized by the original expansion structure within the central part in addition to the structure induced by the latest subduction along the basin *** original spreading structure of the basin presented an east–west linear graben and horst controlled by normal faults during the basin expansion *** a result of the subduction and slab-pull of the Solomon Sea Basin,extensional structure belts parallel to the New Britain Trench formed along the basin margin.

关键词： vertical gravity gradient seismic data tectonics New Britain Trench Solomon Sea Basin