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Keypoint Description Using Statistical Descriptor with Similarity-Invariant Regions

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Computer Systems Science & Engineering 2022年第7期42卷 407-421页

作者： Ibrahim.el rube Sameer Alsharif Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityP.o.Box 11099Taif21944Saudi Arabia

This article presents a method for the description of key points using simple statistics for regions controlled by neighboring key points to remedy the gap in existing ***,the existent descriptors such as speeded up robust features(SURF),Kaze,binary robust invariant scalable keypoints(BRISK),features from accelerated segment test(FAST),and oriented FAST and rotated BRIEF(ORB)can competently detect,describe,and match images in the presence of some artifacts such as blur,compression,and ***,the performance and reliability of these descriptors decrease for some imaging variations such as point of view,zoom(scale),and *** intro-duced description method improves image matching in the event of such *** utilizes a contourlet-based detector to detect the strongest key points within a speciﬁed window *** selected key points and their neighbors con-trol the size and orientation of the surrounding regions,which are mapped on rec-tangular shapes using polar *** resulting rectangular matrices are subjected to two-directional statistical operations that involve calculating the mean and standard ***,the descriptor obtained is invariant(translation,rotation,and scale)because of the two methods;the extraction of the region and the polar transformation techniques used in this *** descrip-tion method introduced in this article is tested against well-established and well-known descriptors,such as SURF,Kaze,BRISK,FAST,and ORB,techniques using the standard OXFORD *** presented methodology demonstrated its ability to improve the match between distorted images compared to other descriptors in the literature.

关键词： Keypoint detection descriptors neighbor region similarity invariance

固相萃取-超高效液相色谱-串联质谱法同时测定水中61种激素

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色谱 2024年第9期42卷 866-874页

作者：陈月琴马明徐红丹潘春燕江苏联合职业技术学院无锡卫生分院江苏无锡214000 无锡市疾病预防控制中心江苏无锡214023

甾体激素类的污染及危害问题不容忽视,为了实现更加全面、准确的高通量分析,研究建立了固相萃取-超高效液相色谱-串联质谱同时测定水中糖皮质激素类(48种)、盐皮质激素类(1种)、雄激素类(4种)及孕激素类(8种)等共61种激素成分的多残留... 详细信息

甾体激素类的污染及危害问题不容忽视,为了实现更加全面、准确的高通量分析,研究建立了固相萃取-超高效液相色谱-串联质谱同时测定水中糖皮质激素类(48种)、盐皮质激素类(1种)、雄激素类(4种)及孕激素类(8种)等共61种激素成分的多残留分析方法。采用HC-C18固相萃取柱对大体积(1 L)水样中的目标化合物进行富集净化,乙腈洗脱,以BEH C18色谱柱分离,以01%甲酸水溶液和乙腈为流动相梯度洗脱,用超高效液相色谱-串联质谱仪分离和检测。质谱采用电喷雾正离子电离、多反应监测模式,外标法定量。61种激素在相应的范围内,线性关系良好,相关系数均大于099,方法检出限为005~150 ng/L,在低、中、高3个加标水平下的回收率为623%~1252%,相对标准偏差为11%~105%。将建立的方法应用于太湖流域的地表水、相关区域的地下水以及末梢水的分析,部分地表水和地下水中检出了可的松、丙酸氟替卡松、环索奈德、倍他米松双丙酸酯、氯倍他松丁酸酯、戊酸双氟可龙、卤倍他索丙酸酯、异氟泼尼龙、二氟孕甾丁酯和己酸羟孕酮等10种成分,其余51种成分未检出。该方法操作简单,灵敏度高,准确度好,对后续水安全的监测以及溯源调查有重要意义。对水中激素水平进行了地区分析,提出了未来污水处理工艺应将激素残留作为目标物进行针对性处理的建议。

关键词：超高效液相色谱-串联质谱固相萃取激素水

Synthesis and applications of lanthanoid complexes of pentadentate and hexadentate N_(5) and N_(6) macrocycles:A review

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Journal of Rare Earths 2024年第1期42卷 1-15,I0001页

作者： Julio Corredoira-Vázquez Cristina González-Barreira Paula Oreiro-martínez Ana m.García-Deibe Jesús Sanmartín-matalobos matilde Fondo Departamento de Química Inorganica Facultade de QuímicaUniversidade de Santiago de CompostelaCampus Vida15782Santiago de CompostelaSpain Phantom-g CICECO-Aveiro Institute of MaterialsDepartment of PhysicsUniversity of Aveiro3810-193AveiroPortugal Institute of materials(imaTUS) Universidade de Santiago de Compostela15782Santiago de CompostelaSpain

In this paper,the lanthanoid complexes of N_(5) and N_(6) macrocycle ligands,without pendant arms or additional heteroatoms,are *** review covers the period from 2015 to the current date,since in 2014 Schiff base macrocyclic ligands incorporating the pyridine moiety,and their complexes,were revised,and in 2015 the chemistry of pentaaza macrocycle ligands with rare earth metals was also *** and phthalocyanine ligands are not included in this review,which primarily focuses on complexes with Schiff bases and amines without pendant arms or any additional donor other than *** synthetic methods,structural characterization,based on single X-ray crystal data,and properties of the lanthanoid complexes,with special attention to magneto-structural correlations,are presented herein.

关键词： Lanthanoid N_(5),N_(6)macrocycle Coordination chemistry Chirality Biological activity molecule magnet

Bi^(3+)、Eu^(3+)共掺杂La_(4)GeO_(8)荧光粉的制备及可调发光

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发光学报 2024年第3期45卷 450-457页

作者：张文娜黎仲寅马纪涛陈娅鹏杨菲郭海南宁理工学院文理学院广西南宁530100 浙江师范大学物理系浙江金华321004

为了开发出高效稳定的单一基质白光发射荧光材料,本工作通过高温固相法成功合成了一系列La_(4)GeO_(8)∶Bi^(3+),Eu^(3+)荧光粉样品,并通过X射线衍射、室温光谱、变温光谱等手段研究了实验样品的结构与发光性能。研究发现,Bi^(3+)离子... 详细信息

为了开发出高效稳定的单一基质白光发射荧光材料,本工作通过高温固相法成功合成了一系列La_(4)GeO_(8)∶Bi^(3+),Eu^(3+)荧光粉样品,并通过X射线衍射、室温光谱、变温光谱等手段研究了实验样品的结构与发光性能。研究发现,Bi^(3+)离子在该结构中占据两种不同的格位(Bi^(3+)(Ⅰ)和Bi^(3+)(Ⅱ)),且在紫外光激发下呈现两个峰值分别在475 nm和620 nm的宽带发射。对于Bi^(3+)、Eu^(3+)共掺样品,由于Bi^(3+)(Ⅰ)与Eu^(3+)之间的竞争吸收、Bi^(3+)(Ⅰ)至Bi^(3+)(Ⅱ)以及Bi^(3+)(Ⅱ)至Eu^(3+)的能量传递作用,可实现蓝色至红色、橙红色至红色的可调发光。特别地,样品La_(4)GeO_(8)∶0.07Bi^(3+),0.06Eu^(3+)在313 nm光激发下可获得CIE值为(0.335,0.319)的优异白色发光。此外,该白光发射材料具有较佳的发光热稳定性,当温度升高至380 K时,发光积分强度仍然为室温的59%,表明其在白光二极管上具有潜在的应用价值。

关键词： La_(4)GeO_(8)∶Bi^(3+),Eu^(3+) 可调发光发光热稳定性白光二极管

Geochemistry of island arc assemblage in the Eastern Desert of Egypt and the role of Pan-African magmatism in crustal growth of the Arabian–Nubian Shield:A review

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Acta Geochimica 2024年第3期43卷 588-622页

作者： Abdel-Aal mabdel-Karim moha.ed mHamdy Adel A.Surour Geology Department Faculty of ScienceZagazig UniversityZagazig 44519Egypt Geology Department Faculty of ScienceTanta UniversityTanta 31527Egypt Department of Geological Sciences Faculty of ScienceNew Galala City 43511Egypt Geology Department Faculty of ScienceCairo UniversityGiza 12613Egypt

Neoproterozoic island arc assemblage of the Arabian–Nubian Shield(ANS)in the Eastern Desert(ed)of Egypt comprises juvenile suites of metavolcanics(mV),large amounts of meta-sedimentary rocks(mS),and voluminous metagabbros-diorites(mGD)and syn-tectonic intrusions of older granitoids(OG).We report here the updates of these four rock units in terms of classification,distribution,chemical characteristics,geodynamic evolution,metamorphism,and *** addition,we discuss these integrated data to elucidate a reasonable and reliable model for crustal evolution in the *** main features of these rock units indicate their relation to each other and the geodynamic environment dominated by early immature oceanic island arcs to primitive continental *** information of the island arc metavolcanic and plutonic rocks(gabbros,diorites,tonalites,and granodiorites)furnish evidence of the genetic *** include proximity and a coeval nature in the field;all protolith magmas are subalkaline in nature following calc-alkaline series with minor tholeiitic affinities;common geochemical signature of the arc rocks and subduction-related magmatism;their similar enrichment in LREEs;and similar major element compositions with mafic melts derived from metasomatized mantle *** volcano-sedimentary and the OG rocks underwent multiphase deformation events whereas the mGD complexes deformed *** on the magmatic,sedimentological,and metamorphic evolutions constrained by geochronological data as well as the progressive evolutionary trend from extensional to compressional regimes,a possible gradual decrease in the subducted slab dip angle is the most infl uential in any geodynamic model for arc assemblage in the ed of Egypt.

关键词： Island arc assemblage magmatism Crustal growth Neoproterozoic Arabian–Nubian Shield Eastern Desert Egypt

单、双指数扩散加权成像联合动态增强磁共振成像对乳腺TICⅡ型良恶性病变的鉴别诊断价值

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临床放射学杂志 2024年第1期43卷 29-33页

作者：马姝杨自力赵凡王唯伟济宁医学院附属医院乳腺外科 272029 济宁医学院附属医院影像科 272029

目的探讨单、双指数扩散加权成像联合动态增强磁共振成像(DWI+IVIm+DCE-mRI模型)对TICⅡ型乳腺良恶性病变的诊断价值方法回顾性分析经病理证实的乳腺肿块患者115例,TICⅡ型良性组30例,恶性组85例,所有病例均行DWI、IVIm及DCE-mRI检查。... 详细信息

目的探讨单、双指数扩散加权成像联合动态增强磁共振成像(DWI+IVIm+DCE-mRI模型)对TICⅡ型乳腺良恶性病变的诊断价值方法回顾性分析经病理证实的乳腺肿块患者115例,TICⅡ型良性组30例,恶性组85例,所有病例均行DWI、IVIm及DCE-mRI检查。分析两组间的表观扩散系数(ADC)、纯扩散系数(D)、灌注相关扩散系数(D^(*))、灌注分数(f)及容量转移常数(K^(trans))、血管外细胞外间隙容积比(V_(e))、速率常数(K_(ep))值;绘制ROC曲线比较其诊断效能。结果TICⅡ型良性组ADC、D值高于恶性组,而K^(trans)、K_(ep)、V_(e)值低于恶性组,差异有统计学意义(P0.05),但D值的特异度及准确度最高。DWI模型的AUC为0.725,IVIm模型的AUC为0.818;DCE-mRI模型的AUC为0.800;DWI+IVIm模型、DWI+DCE-mRI模型的AUC分别为0.860、0.861,诊断效能均高于DWI模型(Z=2.76,P=0.01;Z=3.380,P=0.001)。将DWI、IVIm及DCE-mRI三者联合后,诊断效能高于DWI+IVIm及DWI+DCE-mRI(Z=2.08,P=0.04;Z=1.877,P=0.04)。结论DWI+IVIm+DCE-mRI对TICⅡ型乳腺良恶性病变有较好的鉴别诊断价值,有利于患者术前精准治疗。

关键词：乳腺肿瘤扩散加权成像体素内不相干运动动态增强磁共振成像

表面增强拉曼光谱法同时检测果汁中的啶虫脒和福美双

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食品科学 2024年第2期45卷 283-289页

作者：马立鑫吴玮许骞尹丽梅韩恩白竣文蔡健荣江苏大学食品与生物工程学院江苏镇江212013 江苏大学农业工程学院江苏镇江212013

目的:基于优化的金银合金纳米颗粒基底的表面增强拉曼光谱(surface-enhanced Raman spectroscopy,SERS)同时检测果汁中啶虫脒和福美双。方法:对不同质量浓度的啶虫脒和福美双标准溶液及其混合物采集拉曼光谱并进行峰位归属分析,选择苹... 详细信息

目的:基于优化的金银合金纳米颗粒基底的表面增强拉曼光谱(surface-enhanced Raman spectroscopy,SERS)同时检测果汁中啶虫脒和福美双。方法:对不同质量浓度的啶虫脒和福美双标准溶液及其混合物采集拉曼光谱并进行峰位归属分析,选择苹果汁作为代表果汁样本,对不同质量浓度梯度的混合农药残留进行检测分析,利用两种农药的拉曼特征峰强度与农药残留质量浓度分别建立校正曲线。最后通过回收率实验评估此方法的准确性和精密度。结果:631 cm^(-1)处的拉曼特征峰作为啶虫脒的识别峰,1380 cm^(-1)处的拉曼峰作为福美双的识别峰,同时检测苹果汁中混合农药残留,得到啶虫脒和福美双的检测限分别为0.42231 mg/L和0.03556 mg/L,均低于国家规定的苹果中啶虫脒(0.8 mg/L)和福美双(5 mg/L)的农药残留限量。回收率实验显示苹果汁中福美双和啶虫脒的平均回收率分别为81.67%~101.25%和98.70%~119.36%,相对标准偏差范围分别为2.72%~7.68%和5.44%~15.15%。结论:利用SERS技术的峰尖锐、峰宽窄的特点,结合金银合金纳米颗粒基底可实现果汁中啶虫脒和福美双的同时定量检测。此方法可以进一步应用于其他多种污染物的现场同时快速检测。

关键词：表面增强拉曼光谱啶虫脒福美双同时检测果汁

A NEW HYBRIDIZed mIXed WEAK GALERKIN mETHOD FOR SECOND-ORDER elLIPTIC PROBLEmS

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Journal of Computational mathematics 2022年第4期40卷 499-516页

作者： Abdelhamid Zaghdani Sayed Sayari miled el Hajji University of Tunis Boulevard du 9 avril 1939 TunisDepartment of MathematicsEnsitTaha Hussein AvenueMontfleuryTunisTunisia Northern Border University Faculty of Arts and ScienceRafhaP.O.840Saudi Arabia Carthage University Isteub2 Rue de l’Artisanat Charguia 22035 TunisTunisia Department of mathematics Faculty of SciencesUniversity of JeddahSaudi Arabia ENIT-LAMSINBP.371002 Tunis-Belv´ed`ereTunis El Manar UniversityTunisia

In this paper,a new hybridized mixed formulation of weak Galerkin method is studied for a second order elliptic *** method is designed by approximate some operators with discontinuous piecewise polynomials in a shape regular finite element *** discrete inequalities are presented on discontinuous spaces and optimal order error estimations are *** numerical results are reported to show super convergence and confirm the theory of the mixed weak Galerkin method.

关键词： Weak Galerkin Weak gradient Hybridized mixed finite element method Second order elliptic problems

Geothermobarometry of Askaoun Pluton in Ouzellarh-Sirwa Promontory (Central Anti-Atlas;morocco)

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Open Journal of Geology 2012年第3期2卷 136-147页

作者： Abdeslam Toummite moha Ikenne el Hassane Beraaouz Applied Geology and Environmental Geology Laboratory Faculty of Sciences Ibn Zohr University Agadir Morocco

Rocks of the late Neoproterozoic Askaoun pluton (558 ± 2 ma) located in the Ouzellarh-Sirwa promontory (Anti-Atlas) include magmatic microgranular enclaves (mmEs) ranging from rounded to ovoid in shape, dark and fine grained and generally 5 to 10 cm in size, some reaching a size of 50 cm. They are composed of microdiorite, quartz microdiorite and micromonzodiorite, whereas the felsic host rocks comprise mainly quartz-diorite and amphibole-biotite granodiorite based on mineralogical compositions. The mineral assemblage is similar to those described in their hosting granitoids but with different proportions. In this study composition of minerals is used to describe the nature of the magma and estimate the pressure, temperature and oxygen fugacity at which Askaoun pluton is emplaced. Based on chemistry of biotite Askaoun pluton formed from calc-alkaline magma. Compositions of plagioclase (An5 - An29);hornblende (mg ≠= 0.59 - 0.65) and biotite (mg ≠= 0.49 - 0.55) of mmEs are slightly distinct or similar to those of host rocks (An7-40;hbl mg ≠= 0.64 - 0.69;Bi mg ≠= 0.49 - 0.50) which suggest partial to complete equilibration during mafic-felsic magma interaction. The coexisting hornblende and plagioclase (hornblende-plagioclase thermometry), Al content in hornblende (aluminum-in-hornblende barometry) and the assemblage titanite-magnetite-quartz were used to constrain the P, T and fO2 during the crystallization of the parent magmas. The Askaoun pluton was emplaced at temperature ca. 504°C - 633°C and at pressure ca. 0.9 - 4.66 ± 0.6 Kbars (average depth = 6.5 km) from a highly oxidized magma (log fO2 = ?24.8 to ?19.2).

关键词： Askaoun Pluton mmEs Hornblende Thermobarometry Ouzellargh-Sirwa Promontory Anti-Atlas morocco