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A sensitive method for rapid determination of 256 semi-volatile organic compounds(SVOCs)in water by solid-phase extraction and GC-MS/MS
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作者 Youchang Zhu Ruohan Sun +5 位作者 Yanran Dong Yan Liu Yupeng Chen Zhiquan Yuan Baozhu Pan Nan Xu 《Journal of Environmental Sciences》 2026年第1期362-373,共12页
A trace analytical method based on solid-phase extraction gas chromatography-tandem mass spectrometry(SPE–GC–MS/MS)was developed for the rapid detection of 256 semi-volatile organic compounds(SVOCs),including 25 pol... A trace analytical method based on solid-phase extraction gas chromatography-tandem mass spectrometry(SPE–GC–MS/MS)was developed for the rapid detection of 256 semi-volatile organic compounds(SVOCs),including 25 polycyclic aromatic hydrocarbons(PAHs),70 polychlorinated biphenyls(PCBs),123 pesticides,20 phthalate esters(PAEs),4 organophosphate esters(OPEs),9 synthetic musks(SMs),and 5 UV filters(UVs)in water.No-tably,this method provided a decent linearity of calibration standards(R^(2)>0.999),excellent method limits of quantification(MLOQs)(0.12–11.41 ng/L),satisfactory matrix spiking recovery rates(60.4%–126%),and high precision(intra-day relative standard deviations(RSDs):1.0%–10.0%,inter-day RSDs:3.0%–15.0%,and inter-week RSDs:3.4%–15.7%),making it suitable for trace-level studies.Statistical analysis revealed that SVOCs with higher volatility exhibited enhanced recovery rates.Validation of the methodology involved analyzing SVOCs in real spring water and river water samples.Twenty-seven SVOCs were detected in spring water and 58 in river water,with an average concentration of 631.73 and 16,095 ng/L,respectively.Among the detected SVOCs,PAEs constituted the predominant proportion.This study underscored the presence of SVOCs contamination specifi-cally within the spring water,although SVOCs concentrations in river water were significantly greater than those found in spring water.In summary,this sensitive method based on SPE–GC–MS/MS was successfully developed and validated for the rapid analysis of a diverse array of 256 SVOCs at trace levels in water,including not only the traditional highly valued PAHs,PCBs,pesticides,and PAEs,but also the emerging OPEs,UVs,and SMs. 展开更多
关键词 Semi-volatile organic compounds Spring water gc-ms/MS Organophosphate esters Synthetic musks UV filters
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基于GC-MS指纹图谱和化学计量学评价重楼挥发油质量
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作者 董雨欣 陈建辉 +5 位作者 李娜 朱童岩 于永洲 崔晓燕 赵春颖 熊辉 《中成药》 北大核心 2026年第1期23-27,共5页
目的评价重楼挥发油质量。方法指纹图谱建立采用Shimadzu HP-5MS毛细管柱(30 m×0.25 mm,0.25μm);载气高纯氦气;体积流量1.0 mL/mL;进样口温度250℃;程序升温;电子轰击离子源,轰击能量70 eV;全扫描数据方式。再进行主成分分析和正... 目的评价重楼挥发油质量。方法指纹图谱建立采用Shimadzu HP-5MS毛细管柱(30 m×0.25 mm,0.25μm);载气高纯氦气;体积流量1.0 mL/mL;进样口温度250℃;程序升温;电子轰击离子源,轰击能量70 eV;全扫描数据方式。再进行主成分分析和正交偏最小二乘判别分析。结果20批样品指纹图谱中有21个共有峰,指认出21种成分,相似度均大于0.800(CL006除外)。各批样品(CL038、CL046除外)分为3类,花生酸和反油酸乙酯为潜在质量标志物。结论该方法稳定可靠,可有效识别不同地区重楼挥发油的质量差异,从而为完善该药材质量标准提供理论依据。 展开更多
关键词 重楼 挥发油 质量评价 gc-ms指纹图谱 主成分分析 正交偏最小二乘判别分析
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基于GC-MS技术揭示AMF接种对Cd污染土壤辣椒根际分泌物的重塑效应
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作者 彭世清 周鹏 邢丹 《贵州农业科学》 2026年第2期139-149,共11页
【目的】探明丛枝菌根真菌(AMF)共生对辣椒根际分泌物的重塑效应与辣椒根际的特异性代谢物在Cd胁迫响应中的作用,同步实现Cd解毒与连作障碍消减,为Cd污染土壤的微生物修复提供理论依据。【方法】以辣椒品种辣研201为研究对象进行盆栽试... 【目的】探明丛枝菌根真菌(AMF)共生对辣椒根际分泌物的重塑效应与辣椒根际的特异性代谢物在Cd胁迫响应中的作用,同步实现Cd解毒与连作障碍消减,为Cd污染土壤的微生物修复提供理论依据。【方法】以辣椒品种辣研201为研究对象进行盆栽试验,分别接种根内根生囊霉(Rhizophagus intraradices,Ri)、摩西管柄囊霉(Funneliformis mosseae,Fm),以不接种为对照(CK),测定辣椒生长指标、Cd富集情况,并采用GC-MS技术鉴定分泌物,分析接种AMF对Cd污染土壤中辣椒生长、Cd积累及根际分泌物组成的影响。【结果】Ri处理株高、地上部干物质量、根部干物质量、根冠比、壮苗指数均显著高于CK,分别为14.14 cm、0.97 g、0.15 g、0.44、0.36;Fm处理叶面积最大,为24.95 mm^(2),显著高于CK、Ri处理。Fm处理、Ri处理辣椒地上部、地下部的总Cd含量均显著低于CK,其中,Fm处理总Cd积累分别较CK降低54.84%、48.49%,降低总Cd积累的效果最佳。辣椒根际分泌物,CK共检出8种21个化合物,其中,酯类13个,醇类2个,酚类、酸类、抗氧化剂化合物、烯类、酮类、萜类各1个;Ri处理共检出5种13个化合物,其中,酯类8个,烷烃类2个,烯类、醇类、酚类各1个;Fm处理共检出4种10个化合物,其中,酯类7个,酚类、烯类、烷类各1个。AMF接菌后亚油酸甲酯、10-甲基十一烷酸甲酯、邻苯二甲酸二异丁酯、12-甲基十三烷酸甲酯、9-氧代壬酸甲酯、间苯二甲酸二辛酯、5-十四烷基二氢-2(3H)-呋喃酮、抗氧化剂1076、无羁萜、表木栓酸、β-谷甾醇和二十二烯等12个化学成分未检测出。共检测出5个新物质,分别为十九碳烯、正二十七烷、正二十一烷、肉豆蔻酸甲酯和亚麻酸甲酯。【结论】接种Rhizophagus intraradices可提高辣椒株高、地上部干物质量、根冠比及壮苗指数;接种Funneliformis mosseae可扩大叶面积,且降低辣椒地上部与地下部总Cd积累的效果均最佳。接菌后辣椒根际分泌物类型减少,自毒物质β-谷甾醇和无羁萜未被检出;新检出十九碳烯、正二十七烷、正二十一烷、肉豆蔻酸甲酯和亚麻酸甲酯5个新物质。 展开更多
关键词 丛枝菌根真菌 CD污染 辣椒 辣研201 根际分泌物 gc-ms
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基于GC-MS技术构建调味品风味图谱库
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作者 尤笑歌 郑成功 《中国调味品》 北大核心 2026年第2期207-212,共6页
该研究针对调味品风味信息缺乏系统化描述的问题,基于GC-MS技术构建标准化风味图谱库,选取酱油、食醋、腐乳、辣椒酱和豆豉五类样品共100批次,采用DVB/CAR/PDMS固相微萃取纤维头进行挥发性组分提取,经GC-MS分析后共鉴定出112种风味化合... 该研究针对调味品风味信息缺乏系统化描述的问题,基于GC-MS技术构建标准化风味图谱库,选取酱油、食醋、腐乳、辣椒酱和豆豉五类样品共100批次,采用DVB/CAR/PDMS固相微萃取纤维头进行挥发性组分提取,经GC-MS分析后共鉴定出112种风味化合物,结合质谱匹配、保留指数校正与标准品对照完成高置信度定性;构建风味图谱数据库条目结构,整合保留时间、相对丰度、主离子峰(m/z)特征离子、化合物分类与感官属性,实现了风味信息的结构化表达与样品间差异可视化展示,该研究可为调味品风味质量评价与数字化管理提供技术支持。 展开更多
关键词 gc-ms 调味品 风味物质 图谱构建
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岗梅不同部位挥发油化学成分GC-MS分析
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作者 江顺达 庞伟灿 +1 位作者 刘世男 刘军 《北华大学学报(自然科学版)》 2026年第1期130-139,共10页
分析岗梅(Ilex asprella)不同部位的化学成分及其相对含量,为其药用成分开发及药理评价提供理论依据。采用超临界CO_(2)萃取法提取岗梅花、根、嫩枝、老枝、嫩叶和老叶6个部位的挥发油,应用气相色谱-质谱(GC-MS)联用技术分析化学成分和... 分析岗梅(Ilex asprella)不同部位的化学成分及其相对含量,为其药用成分开发及药理评价提供理论依据。采用超临界CO_(2)萃取法提取岗梅花、根、嫩枝、老枝、嫩叶和老叶6个部位的挥发油,应用气相色谱-质谱(GC-MS)联用技术分析化学成分和相对含量;通过主成分分析和聚类分析比较不同部位之间的差异。结果显示:岗梅不同部位挥发油的得率在0.19%~0.71%,共鉴定出105种挥发性化合物;花、根、嫩枝、老枝、嫩叶和老叶分别含有84、64、75、65、84、69种化合物,醇类和醛类是含量最多的化合物,其中,醇类以已醇为主,醛类以2-己烯醛为主;花、根、嫩枝、老枝、嫩叶和老叶共同含有33种挥发性成分,包括2-己烯醛、己醇、苯乙醇、苯乙烯、反式-松香芹醇等;主成分分析表明,每个主成分均与某些特定化合物存在显著的相关性;聚类分析表明,岗梅6个部位的挥发油可分为2类,嫩叶和老叶聚为一类,嫩枝、老枝、花和根聚为一类。本研究为进一步分析不同部位的药用价值提供了理论依据。 展开更多
关键词 岗梅 挥发性成分 气相色谱-质谱(gc-ms) 主成分分析 聚类分析
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Artificial intelligence-enabled high-precision colony extraction and isolation system
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作者 ZHAO Xu-feng JIA Zhi-qiang +5 位作者 CHEN Wei-xue HU Peng-tao SU Xin-ran LI Jun-lin GE Ming-feng DONG Wen-fei 《中国光学(中英文)》 北大核心 2026年第1期190-204,共15页
Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and... Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and biosafety concerns.In this study,we propose a high-precision automated colony extraction and separation system that combines large-field imaging and artificial intelligence(AI)to facilitate intelligent screening and localization of colonies.Firstly,a large-field imaging system was developed to capture high-resolution images of 90 mm Petri dishes,achieving a physical resolution of 13.2μm and an imaging speed of 13 frames per second.Subsequently,AI technology was employed for the automatic recognition and localiza-tion of colonies,enabling the selection of target colonies with diameters ranging from 1.9 to 2.3 mm.Next,a three-axis motion control platform was designed,accompanied by a path planning algorithm for the efficient extraction of colonies.An electronic pipette was employed for accurate colony collection.Additionally,a bacterial suspension concentration measurement module was developed,incorporating a 650 nm laser diode as the light source,achieving a measurement accuracy of 0.01 McFarland concentration(MCF).Finally,the system’s performance was validated through the preparation of an Esckerichia coli(E.coli)suspension.After 17 hours of cultivation,E.coli was extracted four times,achieving the target concentration set by the system.This work is expected to enable rapid and accurate microbial sample preparation,significantly reducing de-tection cycles and alleviating the workload of healthcare personnel. 展开更多
关键词 artificial intelligence colony extraction and isolation large-field imaging AUTOMATION
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HS-SPME-GC-MS分析香菇牛肉酱的挥发性风味成分
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作者 王磊 杨琪 +2 位作者 刘长姣 刘桐汐 陈宇飞 《中国调味品》 北大核心 2026年第2期244-248,共5页
以香菇牛肉酱为研究对象,采用顶空固相微萃取-气质联用法(HS-SPME-GC-MS)对其挥发性风味成分进行分离和鉴定,通过单因素试验和响应面试验分别考察萃取样品量、萃取温度、萃取时间对挥发性风味成分的影响。结果表明,萃取样品量1.9 g、萃... 以香菇牛肉酱为研究对象,采用顶空固相微萃取-气质联用法(HS-SPME-GC-MS)对其挥发性风味成分进行分离和鉴定,通过单因素试验和响应面试验分别考察萃取样品量、萃取温度、萃取时间对挥发性风味成分的影响。结果表明,萃取样品量1.9 g、萃取温度45℃、萃取时间36 min为较优的萃取条件。在此条件下,鉴定出香菇牛肉酱中挥发性风味成分61种,占总挥发性成分的92.67%,主要包括烃类25种、醇类11种、酯类5种、醛类7种、其他类(醚类、硫化物、苯环类等)13种。该研究结果为香菇牛肉酱风味和品质的调控和精深加工提供了参考。 展开更多
关键词 香菇牛肉酱 HS-SPME gc-ms 挥发性风味成分
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Extraction of Perilla Seed Oil Using Supercritical Carbon Dioxide and GC-MS Analysis 被引量:5
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作者 杨丽嫔 周游 +2 位作者 耿姗姗 刘末 雷红 《Agricultural Science & Technology》 CAS 2017年第8期1509-1512,共4页
[Objective] This study was aimed to determine the optimal parameters for the extraction of perilla seed oil to obtain high-quality perilla seed oil and analyze its compositions. [Method] In this study, perilla seed oi... [Objective] This study was aimed to determine the optimal parameters for the extraction of perilla seed oil to obtain high-quality perilla seed oil and analyze its compositions. [Method] In this study, perilla seed oil was extracted using supercritical CO2 (SC-CO2). The effects of extraction time, temperature and pressure were investigated by single-factor experiments and orthogonal array testing (ORT). The chemical compositions of extracted perilla seed oil were investigated by GC-MS. [Result] The optimal conditions for the extraction of perilla seed oil using SC-CO2 were extraction time of 4 h, extraction temperature at 40 ℃, and extraction pressure at 23 MPa. Under these conditions, the extraction yield of perilla seed oil was maximized to 12.43%. GC-MS analysis revealed that perilla seed oil was a complex mixture containing 76.183% α-linolenic acid. [Conclusion] Supercritical CO2 extraction was proven to be an effective technology to extract oil from perilla seed, and GCMS was also a satisfactory method for analyzing the compositions of perilla seed oil. 展开更多
关键词 Perilla seed essential oil Supercritical carbon dioxide extraction Or-thogonal array testing (OAT) gc-ms
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Analysis of volatile components in saffron from Tibet and Henan by ultrasonic-assisted solvent extraction and GC-MS 被引量:1
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作者 贾凌晗 刘一 李玉珍 《Journal of Chinese Pharmaceutical Sciences》 CAS 2011年第4期404-409,共6页
To determine the chemical constituents of volatile components in saffron from the Tibet Autonomous Region and the Henan Province of China and to compare the chemical composition difference in the saffron,the total vol... To determine the chemical constituents of volatile components in saffron from the Tibet Autonomous Region and the Henan Province of China and to compare the chemical composition difference in the saffron,the total volatile components were extracted by ultrasonic-assisted solvent extraction(USE),using five different solvents:diethyl ether,ethanol,ethyl acetate, dichloromethane and acetone,analyzed using gas chromatography-mass spectrometry(GC-MS)and compared to the standard MS data,and their relative contents were calculated by area normalization.The results showed both that USE was an efficient and rapid method for the extraction of the volatile components from saffron and that the components extracted from the same sample using different solvents were different.Comparison of the experimental results of saffron from the Tibet Autonomous Region and the Henan Province of China showed that their volatile components were different in their chemical composition and in their relative percentages.USE/GC-MS is a simple,rapid,and effective method for the analysis of volatile oil components in saffron. 展开更多
关键词 SAFFRON Volatile components Ultrasonic-assisted solvent extraction gc-ms
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GC-MS/MS法测定不同种类中药材农药残留的提取方法研究
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作者 丁富娟 蔡元元 +4 位作者 巴然然 景援朝 刘玉玲 王海燕 纪国力 《食品与药品》 2026年第1期54-61,共8页
目的研究不同种类中药材适用的农药残留前处理方法。方法采用直接提取法、快速样品处理(QuEChERS)法、固相萃取法对9种不同的中药材进行前处理,通过回收率选择最优方法,并采用GC-MS/MS对药材中农药残留量进行测定。结果根茎类及含有大... 目的研究不同种类中药材适用的农药残留前处理方法。方法采用直接提取法、快速样品处理(QuEChERS)法、固相萃取法对9种不同的中药材进行前处理,通过回收率选择最优方法,并采用GC-MS/MS对药材中农药残留量进行测定。结果根茎类及含有大量挥发油的果实、种子类等中药适合使用固相萃取法方式,基质复杂、含色素较多的花、种子类等适合使用固相萃取法方式,含淀粉、糖类较多的种子及含少量脂肪或挥发油的茎及根皮类等适合使用QuEChERS法,基质相对简单的适合使用固相萃取法方式。结论检测不同中药中农药残留量时应根据药材的特性选择合适的前处理方法。 展开更多
关键词 中药 农药残留 gc-ms/MS 前处理方法
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Flexible High-Aspect-Ratio COF Nanofibers:Defect-Engineered Synthesis,Superelastic Aerogels,and Uranium Extraction Applications
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作者 Binbin Fan Jianyong Yu +2 位作者 Xueli Wang Yang Si Peixin Tang 《Nano-Micro Letters》 2026年第5期15-30,共16页
The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precis... The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precisely regulate the growth and stacking of COF grains through a moderate reversed Schiff base reaction,realizing the direct synthesis of COF nanofibers(CNFs)with high aspect ratio(L/D=103.05)and long length(>20μm).An individual CNF exhibits a biomimetic scale-like architecture,achieving superior flexibility and fatigue resistance under dynamic bending via a multiscale stress dissipation mechanism.Taking advantages of these structural features,we engineer CNF aerogels(CNF-As)with programmable porous structures(e.g.,honeycomb,lamellar,isotropic)via directional ice-template methodology.CNF-As demonstrate 100%COF content,high specific surface area(396.15 m^(2)g^(-1))and superelasticity(~0%elastic deformation after 500 compression cycles at 50%strain),outperforming most COF-based counterparts.Compared with the conventional COF aerogels,the unique structural features of CNF-A enable it to perform outstandingly in uranium extraction,with an 11.72-fold increment in adsorption capacity(920.12 mg g^(-1))and adsorption rate(89.9%),and a 2.48-fold improvement in selectivity(U/V=2.31).This study provides a direct strategy for the development of next-generation COF materials with outstanding functionality and structural robustness. 展开更多
关键词 Defect cleavage COF nanofibers Flexibility AEROGELS Uranium extraction
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Quality evaluation and chemical profiling of Cyperi Rhizoma(Xiangfu)using traditional quality assessment,GC-MS,RP-HPLC,and FTIR techniques
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作者 Lu Luo Dong-Han Bai +7 位作者 Shu-Min Chen Da-Jun Lu Nan-Xi Huang Qiao-Chu Wang Jun-Na Yao Lu Jia Zhi-Jie Zhang Rao-Rao Li 《Traditional Medicine Research》 2026年第2期20-29,共10页
Background:Cyperi Rhizoma,derived from Cyperus rotundus L.,is a widely used medicinal herb in traditional Chinese medicine(TCM),with Shandong Province recognized as its geo-authentic habitat.However,the quality of Cyp... Background:Cyperi Rhizoma,derived from Cyperus rotundus L.,is a widely used medicinal herb in traditional Chinese medicine(TCM),with Shandong Province recognized as its geo-authentic habitat.However,the quality of Cyperi Rhizoma varies significantly across different regions,potentially influencing its therapeutic efficacy.This study investigates the influence of geographic origin on the chemical composition and overall quality of Cyperi Rhizoma.Methods:A comprehensive approach,including traditional quality assessment,GC-MS(g as c hromatography-m ass s pectrometry),RP-HPLC(r everse p hase h igh-p erformance l iquid c hromatography),and FT-IR(f ourier t ransform i nfrared s pectroscopy)techniques,was employed to analyze Cyperi Rhizoma samples from Shandong Province.These methods examined the physical appearance,chemical profile,and content variations,particularly focusing onα-cyperone.Results:Traditional quality assessments revealed noticeable differences in the external characteristics of the samples.GC-MS analysis identified a variety of unique chemical constituents,while RP-HPLC and FT-IR showed significant variations inα-cyperone content,with higher levels found in Shandong samples.Conclusion:These results demonstrate that geographic origin is a critical determinant of Cyperi Rhizoma quality,with Shandong specimens exhibiting superiorα-cyperone levels and characteristic phytochemical profiles.This validates the geo-authenticity concept in TCM and provides actionable data for developing evidence-based quality standards,suggesting that provenance should be prioritized in medicinal material selection and pharmacopeial specifications. 展开更多
关键词 Cyperi Rhizoma traditional Chinese medicine gc-ms FTIR quality
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Straightforward and versatile construction of phenanthroline-derived diamide ligands for f-block element extraction
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作者 Dong Fang Xiaofan Yang +1 位作者 Fengxin Gao Chengliang Xiao 《Chinese Chemical Letters》 2026年第1期602-605,共4页
As an important class of phenanthroline derivatives containing soft N and hard O donor atoms,the laborious syntheses of unsymmetrical 1,10-phenanthroline-derived diamide ligands(DAPhen) have hindered its extensive stu... As an important class of phenanthroline derivatives containing soft N and hard O donor atoms,the laborious syntheses of unsymmetrical 1,10-phenanthroline-derived diamide ligands(DAPhen) have hindered its extensive study.In this work,we first report a convenient synthetic method for the construction of DAPhen using Friedländer reaction by two facile steps(vs.previous 12 steps).A variety of DAPhen ligands are readily available,especially unsymmetrical ones,which give us a platform to systematically study the substituent effect on f-block elements extraction performance.The performance of unsymmetrical extractants is experimentally confirmed to falls between that of their corresponding symmetrical extractants by extracting UO_(2)^(2+) as the representative f-block element.This work provides a direct and versatile method to synthesize symmetrical and unsymmetrical DAPhen,which paves way for the investigations on their coordination properties with metal ions and other applications. 展开更多
关键词 Phenanthroline diamide ligand Friedlander reaction UNSYMMETRICAL SYMMETRICAL Solvent extraction
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T-Pointer:A Chinese Text Semantic Extraction Model for Semantic Communication
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作者 Qian Liping Qian Jiang +3 位作者 Wu Wanwan Huang Liang Wu Yuan Yang Xiaoniu 《China Communications》 2026年第2期298-311,共14页
Text semantic extraction has been envisioned as a promising solution to improve the data transmission efficiency with the limited radio resources for the autonomous interactions among machines and things in the future... Text semantic extraction has been envisioned as a promising solution to improve the data transmission efficiency with the limited radio resources for the autonomous interactions among machines and things in the future sixth-generation(6G)wireless networks.In this paper,we propose a Chinese text semantic extraction model,namely T-Pointer,to improve the quality of semantic extraction by integrating the Transformer with the pointer-generator network.The proposed T-Pointer model consists of a semantic encoder and a semantic decoder.In the encoding stage,we use the multi-head attention mechanism of the Transformer to extract semantic features from the input Chinese text.In the decoding stage,we first use the Transformer to extract multi-level global text features.Then,we introduce the pointer-generator network model to directly copy the keyword information from the source text.The simulation results demonstrate that the T-Pointer model can improve the bilingual evaluation understudy(BLEU)and recalloriented understudy for gisting evaluation(ROUGE)by 14.69%and 14.87%on average in comparison with the state-of-the-art models,respectively.Also,we implement the T-Pointer model on a semantic communication system based on the universal software radio peripheral(USRP)platform.The result shows that the packet delay of semantic transmission can be reduced by 52.05%on average,compared to traditional information transmission. 展开更多
关键词 attention mechanism pointer-generator network semantic communication semantic extraction TRANSFORMER
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Highly enhanced scandium extraction and back-extraction efficiencies using a new C272–iso-octanol synergistic system
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作者 Ziyun Zhang Yanlin Zhang +5 位作者 Wenyu Shen Dapeng Guo Hongbo Wang Duo Wang Fang Zhou Chao Yang 《Chinese Journal of Chemical Engineering》 2026年第1期198-207,共10页
This article presents a new synergistic extraction system composed of Cyanex 272(C272,bis(2,4,4-trimethylpentyl)phosphinic acid)and iso-octanol for Sc_(3+) separation.The proposed synergistic system possessed an Sc^(3... This article presents a new synergistic extraction system composed of Cyanex 272(C272,bis(2,4,4-trimethylpentyl)phosphinic acid)and iso-octanol for Sc_(3+) separation.The proposed synergistic system possessed an Sc^(3+) extraction efficiency of 93.5%and a back-extraction efficiency of 82.7%,with selectivity coefficients of β_(Sc/Fe)=459 and β_(Sc/Al)=4241,which are considerably higher as compared to the current extraction systems.The extraction mechanism was studied and interpreted.The enhanced extraction efficiency is attributed to the increased hydrophobicity of the ternary complex,whereas the back-extraction efficiency can be ascribed to the attenuated stability of the complex.C272 and C272–iso-octanol systems also possess considerable surface activity,which is beneficial for the phase separation in solvent extraction.Based on the solvent extraction results,a preliminary study was conducted on polymer inclusion membranes(PIMs)using the binary system for Sc^(3+) separation to avoid the formation of the third phase,achieving an optimal initial flux of PIM of 6.71×10^(−4)mol·m^(−2)·h^(−1).Our results provide valuable information on highly efficient Sc^(3+) separation,and the study on PIM extraction has shown a green alternative to solvent extraction. 展开更多
关键词 SCANDIUM Solvent extraction Polymer inclusion membrane C272 Iso-octanol
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Enhanced Multi-Scale Feature Extraction Lightweight Network for Remote Sensing Object Detection
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作者 Xiang Luo Yuxuan Peng +2 位作者 Renghong Xie Peng Li Yuwen Qian 《Computers, Materials & Continua》 2026年第3期2097-2118,共22页
Deep learning has made significant progress in the field of oriented object detection for remote sensing images.However,existing methods still face challenges when dealing with difficult tasks such as multi-scale targ... Deep learning has made significant progress in the field of oriented object detection for remote sensing images.However,existing methods still face challenges when dealing with difficult tasks such as multi-scale targets,complex backgrounds,and small objects in remote sensing.Maintaining model lightweight to address resource constraints in remote sensing scenarios while improving task completion for remote sensing tasks remains a research hotspot.Therefore,we propose an enhanced multi-scale feature extraction lightweight network EM-YOLO based on the YOLOv8s architecture,specifically optimized for the characteristics of large target scale variations,diverse orientations,and numerous small objects in remote sensing images.Our innovations lie in two main aspects:First,a dynamic snake convolution(DSC)is introduced into the backbone network to enhance the model’s feature extraction capability for oriented targets.Second,an innovative focusing-diffusion module is designed in the feature fusion neck to effectively integrate multi-scale feature information.Finally,we introduce Layer-Adaptive Sparsity for magnitude-based Pruning(LASP)method to perform lightweight network pruning to better complete tasks in resource-constrained scenarios.Experimental results on the lightweight platform Orin demonstrate that the proposed method significantly outperforms the original YOLOv8s model in oriented remote sensing object detection tasks,and achieves comparable or superior performance to state-of-the-art methods on three authoritative remote sensing datasets(DOTA v1.0,DOTA v1.5,and HRSC2016). 展开更多
关键词 Deep learning object detection feature extraction feature fusion remote sensing
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LLM-KE: An Ontology-Aware LLM Methodology for Military Domain Knowledge Extraction
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作者 Yu Tao Ruopeng Yang +3 位作者 Yongqi Wen Yihao Zhong Kaige Jiao Xiaolei Gu 《Computers, Materials & Continua》 2026年第1期2045-2061,共17页
Since Google introduced the concept of Knowledge Graphs(KGs)in 2012,their construction technologies have evolved into a comprehensive methodological framework encompassing knowledge acquisition,extraction,representati... Since Google introduced the concept of Knowledge Graphs(KGs)in 2012,their construction technologies have evolved into a comprehensive methodological framework encompassing knowledge acquisition,extraction,representation,modeling,fusion,computation,and storage.Within this framework,knowledge extraction,as the core component,directly determines KG quality.In military domains,traditional manual curation models face efficiency constraints due to data fragmentation,complex knowledge architectures,and confidentiality protocols.Meanwhile,crowdsourced ontology construction approaches from general domains prove non-transferable,while human-crafted ontologies struggle with generalization deficiencies.To address these challenges,this study proposes an OntologyAware LLM Methodology for Military Domain Knowledge Extraction(LLM-KE).This approach leverages the deep semantic comprehension capabilities of Large Language Models(LLMs)to simulate human experts’cognitive processes in crowdsourced ontology construction,enabling automated extraction of military textual knowledge.It concurrently enhances knowledge processing efficiency and improves KG completeness.Empirical analysis demonstrates that this method effectively resolves scalability and dynamic adaptation challenges in military KG construction,establishing a novel technological pathway for advancing military intelligence development. 展开更多
关键词 Knowledge extraction natural language processing knowledge graph large language model
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Recycling of High-Purity Lithium Metal from Waste Battery by Photoelectrochemical Extraction at Ultralow Overall Potential
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作者 Longfei Yang Chao Huang +3 位作者 Yanhong Lyu Dawei Chen Aibin Huang Jianyun Zheng 《Nano-Micro Letters》 2026年第4期371-388,共18页
To ease the scarcity of lithium(Li)resource and cut down on environmental pollution,an efficient,selective,inexpensive and sustainable Li recycling process from waste batteries is needed,which is yet to be achieved.He... To ease the scarcity of lithium(Li)resource and cut down on environmental pollution,an efficient,selective,inexpensive and sustainable Li recycling process from waste batteries is needed,which is yet to be achieved.Here,we report a low-potential photoelectrochemical(PEC)system that selectively and efficiently extracts Li metals from multi-cation electrolytes under 1 sun illumination.Based on the difference of redox potential,we can get rid of the disturbance of other cations(i.e.,Fe,Co and Ni ions)by a bias-free PEC device to realize the extraction of high-purity Li metals on a coplanar Si-based photocathode-TiO_(2) photoanode tandem device at 2 V of applied bias(far less than the redox potentials of Li^(+)/Li).In such system,the extraction rate of Li metals(purity>99.5%)exceeds 1.35 g h^(-1)m^(-2)with 90%of Faradaic efficiency.Long-term experiments,different electrode/electrolyte tests,and various price assessments further demonstrate the stability,compatibility and economy of PEC extraction system,enabling a solar-driven pathway for the recycling of critical metal resources. 展开更多
关键词 Photoelectrochemical method Lithium metals Waste batteries Ultralow-potential device Selective and efficient extraction
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Synergistic lock-anchor engineered diketopyrrolopyrrole-COFs for efficient photocatalytic uranium extraction
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作者 Fengtao Yu Xiaolong Zhang +5 位作者 Jie Xu Guihong Wu Huiying Lei Zhiwu Yu Jianding Qiu Jianli Hua 《Journal of Energy Chemistry》 2026年第1期284-293,I0007,共11页
As a key low-carbon energy source,nuclear power plays a vital role in the global transition toward sustainable energy.Photocatalytic uranium extraction from seawater(UES)offers a promising solution to ensure long-term... As a key low-carbon energy source,nuclear power plays a vital role in the global transition toward sustainable energy.Photocatalytic uranium extraction from seawater(UES)offers a promising solution to ensure long-term uranium supply but is challenged by ultra-low uranium concentrations and ion interference.To overcome these issues,we design three diketopyrrolopyrrole-based covalent organic frameworks(COFs)via a synergisticπ-extended lock and carboxyl-functionalized anchor molecular engineering strategy.Among them,TPy-DPP-COF features a covalently lockedπ-conjugated structure that enhances planarity,optimizes energy alignment,and minimizes exciton binding energy,thereby promoting charge transfer and suppressing recombination.Concurrently,carboxyl groups enable uranyl-specific coordination and create local electric fields to facilitate charge separation.These features contribute to the outstanding performance of TPy-DPP-COF,which achieves a high uranium adsorption capacity of 16.33 mg g−1 in natural seawater under irradiation,with only 29.3%capacity loss after 10 cycles,surpassing industrial benchmarks.Density functional theory(DFT)calculations and experimental studies reveal a synergistic photocatalysis-adsorption pathway,with DPP units acting as active sites for uranium reduction.This work highlights a molecular design strategy for developing efficient COF-based photocatalysts for practical marine uranium recovery. 展开更多
关键词 DIKETOPYRROLOPYRROLE Covalent organic frameworks Exciton binding energy Photocatalytic uranium extraction Synergistic effect
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Long-term outcomes following lens extraction surgery in acute primary angle closure
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作者 Yi-Ning Guo Jing Ding +3 位作者 Hao-Ran Ai Xin-Zuo Zhou Xue-Min Li Chun Zhang 《International Journal of Ophthalmology(English edition)》 2026年第2期281-290,共10页
AIM:To investigate the long-term outcomes in acute primary angle closure(APAC)patients treated with lens extraction(LE)surgery and to identify risk factors for glaucomatous optic neuropathy(GON).METHODS:In this longit... AIM:To investigate the long-term outcomes in acute primary angle closure(APAC)patients treated with lens extraction(LE)surgery and to identify risk factors for glaucomatous optic neuropathy(GON).METHODS:In this longitudinal observational study,detailed medical histories of APAC patients and comprehensive ophthalmic examinations at final followup were collected.Logistic regression analysis was performed to identify predictors of blindness.Univariate and multivariate linear regression analyses were conducted to determine risk factors associated with visual outcomes.RESULTS:This study included 39 affected eyes of 31 subjects(26 females)with an average age of 74.1±8.0y.At 6.7±4.2y after APAC attack,2(5.7%)eyes had bestcorrected visual acuity(VA)worse than 3/60.Advanced glaucomatous visual field loss was observed in 15(39.5%)affected eyes and 5(25.0%)fellow eyes.Nine affected eyes(23.7%)had GON,and 11(28.9%)were blind.Six(15.4%)affected eyes and 2(9.1%)fellow eyes had suspicious progression.A significantly higher blindness rate in factory workers compared to office workers.Logistic regression identified that worse VA at attack(OR 10.568,95%CI 1.288-86.695;P=0.028)and worse early postoperative VA(OR 13.214,95%CI 1.157-150.881;P=0.038)were risk factors for blindness.Multivariate regression showed that longer duration of elevated intraocular pressure(P=0.004)and worse early postoperative VA(P=0.009)were associated with worse visual outcomes.CONCLUSION:Despite LE surgery,some APAC patients experience continued visual function deterioration.Lifelong monitoring is necessary.Target pressure and progression rates should be re-evaluated during follow-up. 展开更多
关键词 acute primary angle closure lens extraction surgery long-term follow-up visual impairment glaucomatous optic neuropathy
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