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注射用头孢西丁钠有关物质测定方法的改进

中国抗生素杂志 2024年第3期49卷 341-347页

作者：王强韩彬王韵杨天风李聪颖高燕霞河北省药品医疗器械检验研究院石家庄050020 河北科技大学石家庄050018

目的改进注射用头孢西丁钠有关物质的测定方法。方法采用苯基硅烷键合硅胶为填充剂(Inertsil Ph-3色谱柱4.6 mm×250 mm,3μm);以甲酸铵缓冲液(取甲酸铵1.0 g,加水1000 mL使溶解,用甲酸调节pH值至2.7)为流动相A,乙腈为流动相B,按线性梯... 详细信息

目的改进注射用头孢西丁钠有关物质的测定方法。方法采用苯基硅烷键合硅胶为填充剂(Inertsil Ph-3色谱柱4.6 mm×250 mm,3μm);以甲酸铵缓冲液(取甲酸铵1.0 g,加水1000 mL使溶解,用甲酸调节pH值至2.7)为流动相A,乙腈为流动相B,按线性梯度洗脱,流速为1.0 mL/min,柱温为35℃,检测波长为254 nm。结果头孢西丁峰与各杂质峰分离良好,头孢西丁在0.0446~13.3692μg/mL范围内线性良好,检出限为0.89 ng,精密度与重复性均符合规定。结论本方法灵敏度高,分离效果好,可现实对头孢西丁钠已知杂质和聚合物杂质进行同时检测。

关键词：注射用头孢西丁钠有关物质聚合物方法优化质量控制

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最大SNR准则的共形阵列波束合成方法

电讯技术 2024年第3期64卷 436-441页

作者：张华健李聪颖黄治磊周文斐曾浩北京卫星信息工程研究所北京100095 海军研究院系统研究所北京100036 重庆大学微电子与通信工程学院重庆400044

相控阵波束合成的最终目的是提高接收信号的信噪比(Signal-to-Noise Ratio,SNR),但是由于共形阵阵面是弯曲的,各个阵元具有不同的接收SNR,把所有阵元移相后直接进行波束合成并不能保证获得最大SNR。在考虑单元方向图影响情况下,通过对... 详细信息

相控阵波束合成的最终目的是提高接收信号的信噪比(Signal-to-Noise Ratio,SNR),但是由于共形阵阵面是弯曲的,各个阵元具有不同的接收SNR,把所有阵元移相后直接进行波束合成并不能保证获得最大SNR。在考虑单元方向图影响情况下,通过对共形相控阵天线接收SNR解析表示,采用迭代方式对阵元是否接入波束合成进行判断,确保了天线具有最大SNR输出。计算机仿真证实了阵元选择方法的正确性。

关键词：相控阵共形阵列波束合成阵元选取

An Anti-Recompression Video Watermarking Algorithm in Bitstream Domain

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Tsinghua Science and Technology 2021年第2期26卷 154-162页

作者： Jing Sun Xiaoping Jiang Jin liu Fan Zhang congying li Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518055China Shenzhen Beidou Applied Technology Research Institute Shenzhen 518055China College of Electrical and Information Engineering South-Central University for NationalitiesWuhan 430074China

Following the popularity of digital video application,video copying and dissemination have become very easy;however,this makes video hacking and piracy a potential threat in video *** watermarking technology can solve the problem of copyright protection,and thus,it has been extensively *** robustness of the video watermarking algorithm in the bitstream domain is poor,especially the anti-recompression ability,since the watermarked video may be compressed again before *** this,this paper proposes a video watermarking algorithm in the bitstream domain based on moving object *** increase the robustness of the watermarking scheme,the moving macroblocks that belong to the moving object in each P frame can be identified via the moving object detection ***,watermark embedding in the moving macroblocks is performed using codeword substitution to ensure the consistency of the *** object detection and watermark embedding are independent and are both carried out in the bitstream domain by partially decoding the bitstream;this avoids the complete decoding and reconstruction of the video,making the method to be highly *** simulation results confirm that the proposed method is robust against recompression and has little impact on the video visual quality and no influence on the bit rate.

关键词： video watermarking recompression moving object detection

Plate subduction, oxygen fugacity, and mineralization

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Journal of Oceanology and limnology 2020年第1期38卷 64-74页

作者： liU He liAO Renqiang ZHANG lipeng li congying SUN Weidong Key Laboratory of Marine Geology and Environment Center of Deep-Sea ResearchInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources Laboratory for Marine Biology and BiotechnologyPilot National Laboratory for Marine Science and TechnologyQingdao 266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

Plate subduction is the largest natural factory that processes elements,which controls recycling and mineralization of a variety of *** are three major ore deposit belts in the world:the circumPacific,the centralAsian,and the Tethys *** the three belts are closely associated with plate subductions,the mechanism remains *** approached this problem from systematic studies on the behaviours of elements during geologic *** contribution summaries the recent progress of our research *** results suggest that porphyry Cu deposits form through partial melting of subducted young oceanic crust under oxygen fugacities higher than AFMQ^+1.5,which is promoted after the elevation of atmospheric oxygen at ca.550 *** deposits are associated with reducing magmatic rocks formed as a consequence of slab *** Neo-Tethys tectonic regime hosts more than 60%of the world's total Sn *** is due to the reducing environment formed during the subduction of organic rich *** the same reason,porphyry Cu deposits formed in the late stages during the closure of the Neo-Tethys *** deposits are also controlled by slab rollback,but is not so sensitive to oxygen *** related W/Sn deposits are mostly accompanied by abundant accessory fluorites due to the breakdown of phengite and *** of phengite is also significant for hard rock lithium deposits,whereas orogenic belt resulted from plate subduction promote the formation of li brine *** red bed basins near the Nanling region are favorable for li *** Mo and Re are enriched in the oxidationreduction cycle during surface processes,and may get further enriched once Mo-,Re-enriched sediments are subducted and involved in *** plate subduction,Mo and Re fractionate from each *** is mainly hosted in porphyry Mo deposits and to a less extent,porphyry Cu-Mo deposits,whereas Re is predominantly hosted in

关键词： plate subduction oxygen fugacity ore deposits geochemical behaviors subduction factory

厦门市翔安区2017—2023年活禽交易市场环境禽流感监测结果分析

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海峡预防医学杂志 2024年第2期30卷 82-84页

作者：李聪颖李诗逸陈滨滨苏辉耀厦门市翔安区疾病预防控制中心福建厦门361102

目的监测厦门市翔安区活禽交易市场环境禽流感情况,分析H5等亚型在外环境中的分布规律,研判对市场职业暴露人员健康的风险等级。方法2017—2023年在翔安区每年1月和7月采集活禽交易市场不同环境标本,用real-time RT-PCR法进行禽流感病... 详细信息

目的监测厦门市翔安区活禽交易市场环境禽流感情况,分析H5等亚型在外环境中的分布规律,研判对市场职业暴露人员健康的风险等级。方法2017—2023年在翔安区每年1月和7月采集活禽交易市场不同环境标本,用real-time RT-PCR法进行禽流感病毒各亚型的特异性核酸检测,用血凝抑制试验进行市场职业暴露人群血清禽流感抗体检测。结果共采集环境标本145份,A型、H5、H7N9和H9亚型的平均阳性率,分别为66.9%、0.7%、2.8%和32.4%;H9亚型占A型的48.5%(47/97);在表面擦拭、粪便和水标本中A型流感阳性率分别为70.6%、64.4%和71.4%(χ^(2)=0.648,P=0.723);175份禽流感职业暴露人群血清标本,H5N6、H9N2和H7N9禽流感抗体检测结果均阴性。结论厦门市翔安区活禽交易市场环境标本A型流感阳性率较高,职业暴露人群感染禽流感有一定风险;H9亚型是环境标本中A型流感的优势株;3类环境标本中A型流感的阳性率差异不大;应加强活禽交易市场禽流感的病原学监测。

关键词：禽流感病原学监测禽交易市场 A型流感暴露人员健康风险

棕色中硼硅玻璃安瓿包装盐酸氨溴索注射液的元素迁移量及内表面脱片的研究

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中国药品标准 2024年第3期25卷 313-320页

作者：杨启乐李总盛李雷张海翔李从英山东力诺特种玻璃股份有限公司济南251600

目的:考察棕色中硼硅玻璃安瓿对盐酸氨溴索注射液药品安全性的影响。方法:通过模拟盐酸氨溴索注射液的存放条件,利用电感耦合等离子体发射光谱仪(ICP-OES)和扫描电镜(SEM)设计实验研究元素迁移量及内表面脱片情况。结果:随着时间的推移... 详细信息

目的:考察棕色中硼硅玻璃安瓿对盐酸氨溴索注射液药品安全性的影响。方法:通过模拟盐酸氨溴索注射液的存放条件,利用电感耦合等离子体发射光谱仪(ICP-OES)和扫描电镜(SEM)设计实验研究元素迁移量及内表面脱片情况。结果:随着时间的推移,注射液中Si元素含量增加,经过0~48月各阶段试验后的玻璃样品内表面未出现脱片现象;Cd、Pb、As等各类元素向注射液中发生了迁移,但含量未超出相关规定限值。结论:棕色中硼硅玻璃安瓿包装盐酸氨溴索注射液在48月内安全稳定,棕色中硼硅玻璃安瓿可作为盐酸氨溴索注射液的良好盛装容器。

关键词：盐酸氨溴索注射液棕色中硼硅玻璃安瓿元素迁移量内表面脱片电感耦合等离子体发射光谱仪扫描电镜

Plate convergence in the Indo-Pacific region

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Journal of Oceanology and limnology 2020年第4期38卷 1008-1017页

作者： SUN Weidong ZHANG lipeng liAO Renqiang SUN Saijun li congying liU He Center of Deep Sea Research Institute of OceanologyCenter for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

The Indo-Pacific convergence region is the best target to solve the teo remaining challenges of the plate tectonics theory,i.e.,subduction initiation and the driving force of plate *** studies proposed that the Izu-Bonin subduction initiation belongs to spontaneous initiation,which implies that it started from extension,followed by low angle *** geodynamic modeling suggests that the initiation of plate subduction likely occurred along a transform fault,which put the young spreading ridge in direct contact with old oceanic ***,however,does not explain the simultaneous subduction initiation in the west Pacific region in the ***,the subduction initiations in the Izu-BoninMariana,the Aleutian,and the Tonga-Kermadec trenches are associated with oceanic crusts of different ages,yet they occurred at roughly the same time,suggesting that they were all triggered by a maj or change in the Pacific ***,low angle subduction induces compression rather than extension,which requires external compression *** that the famous Hawaiian-Emperor bending occurred roughly at the same time with the onset of westward subductions in the west Pacific,we propose that these Cenozoic subductions were initiated by the steering of the Pacific plate,which are classified as induced *** subduction initiation usually occurs in young ocean basins,forming single-track *** closure s of Neo-Tethys Oceans were likely triggered by plume s in the south,forming northward ***,the Indian plate kept on moving northward more than 50 Ma after the collision between the Indian and Eurasian continents and the break-off of the subducted oceanic slab attached to *** strongly suggests that slab pull is not the main driving force of plate tectonics,whereas slab sliding is.

关键词： plate tectonics subduction initiation drifting history Pacific plate Indian plate slab sliding

Geochemical and Zircon Hf-O Isotopic Constraints on the Origin of Wulian A-Type Granite in Shandong Peninsula,Eastern China

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Journal of Earth Science 2022年第3期33卷 609-622页

作者： Shuai Yuan He li lipeng Zhang congying li Haiyang liu Ying-Yu Xue Weidong Sun Center of Deep Sea Research Institute of OceanologyCenter for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China School of Marine Sciences University of Chinese Academy of SciencesBeijing 100049China

Early Cretaceous A-type granitic plutons are widely distributed in Shandong Peninsula,which are of great significance to understanding the regional tectonic *** we report geochemical characteristics,geochronological results,and zircon Hf-O isotope compositions of Wulian granites to reveal its origin and geological *** granites share most characteristics of the A_(2)-type *** U-Pb LA-ICPMS analysis for Wulian A-type granites yields average age of 116.6±2.1 *** O isotope values range from 4.20‰to 5.57‰,and these values are marginally identical to or slightly lower than those of mantle zircon(5.3‰±0.3‰).Zirconε_(Hf)(t)values(-26.1--23.5)indicate an enriched *** zircon Hf-O isotope compositions indicate that the source region of Wulian granites involves the components of ancient oceanic *** from Wulian granites have the lower chlorine(0.06 wt.%-0.15 wt.%)and higher fluorine contents(2.11 wt.%-2.48 wt.%)compared with Haiyang pluton,together with their high(La/Gd)_(N),(La/Yd)_(N) and low(Gd/Yb)_(N) ratios and high oxygen state magma reflected from zircon,signifying that slab derived component was added into the overlying mantle region through fluid/*** geochemical characteristics of Wulian granites could be explained by the ridge(between the Izanagi and Pacific plates)subduction model,which began to influence the tectonic evolution of the Xuhuai region and Shandong Peninsula since~130±5 *** following slab window between two plates plausibly explains regional extension,resulting in hot magma upwelling and the formation of the A-type granite *** the Lower Yangtze River belt and Shandong Peninsula A-type granite proves the northward movement of the ridge between the Pacific Plate and Izanagi Plate.

关键词： A-type granite Shandong Peninsula ridge subduction zircon Hf-O isotope magma

Pickering乳液自组装CL-20/n-Al/F2605复合空心微球的制备与性能

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爆破器材 2024年第4期53卷 9-16页

作者：孙鹏瞻杨敏尢淇高登钊李聪颖张行泉郭长平西北工业大学伦敦玛丽女王大学工程学院陕西西安710129 西南科技大学四川省新型含能材料军民融合创新中心四川绵阳621010 山西北化关铝化工有限公司山西永济044500

高能量、高爆热的六硝基六氮杂异伍兹烷(CL-20)/Al复合物由于自身的高感度而限制了在炸药领域的广泛应用。为制备高能量和高安全性的CL-20/Al含能复合材料,采用Pickering乳液法制备了空心球形CL-20/n-Al/F2605(氟橡胶)复合物,并对Picker... 详细信息

高能量、高爆热的六硝基六氮杂异伍兹烷(CL-20)/Al复合物由于自身的高感度而限制了在炸药领域的广泛应用。为制备高能量和高安全性的CL-20/Al含能复合材料,采用Pickering乳液法制备了空心球形CL-20/n-Al/F2605(氟橡胶)复合物,并对Pickering乳液稳定性、复合物表面结构、热分解、燃烧及安全性能进行了分析。结果显示:当2 mL乙酸乙酯中溶解的CL-20固体质量为0.10~0.14 g、油水质量比在1:5~1:7之间、超声时间小于30 min、静置时间小于120 min时,形成的乳液稳定性好。该复合物表面结构粗糙,中位径d_(50)为73.17μm,各组分复合均匀。复合物的热分解峰温和活化能分别为236.7℃、164.6 kJ/mol,n-Al和F2605降低了CL-20分解过程中21.2%的活化能。复合物平均线性燃速为7.14 cm/s;特性落高H_(50)为39.5 cm,和原料CL-20相比提升了26.5 cm,安全性能得到提高。

关键词：六硝基六氮杂异伍兹烷(CL-20) 纳米铝粉(n-Al) 微球 Pickering乳液

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