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Acoustic localization with multi-layer isogradient sound speed profile using TDOA and FDOA

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Frontiers of Information Technology & Electronic Engineering 2023年第1期24卷 164-175页

作者： Dongzhou ZHAN sitian wang Shougui CAI Huarong ZHENG Wen XU College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027China Key Laboratory of Ocean Observation-Imaging Testbed of Zhejiang Province Ocean CollegeZhejiang UniversityZhoushan 316021China

In the underwater medium,the speed of sound varies with water depth,temperature,and *** inhomogeneity of water leads to bending of sound rays,making the existing localization algorithms based on straightline propagation less *** realize high-precision node positioning in underwater acoustic sensor networks(UASNs),a multi-layer isogradient sound speed profile(SSP)model is developed using the linear segmentation approximation ***,the sound ray tracking problem is converted into a polynomial root-searching *** on the derived gradient of the signal’s Doppler shift at the sensor node,a novel underwater node localization algorithm is proposed using both the time difference of arrival(TDOA)and frequency difference of arrival(FDOA).Simulations are implemented to illustrate the effectiveness of the proposed *** with the traditional straight-line propagation method,the proposed algorithm can effectively handle the sound ray bending *** accuracy with different SSP modeling errors is also ***,accurate and reliable node localization can be achieved.

关键词： Underwater acoustic sensor network Acoustic localization Sound speed profile Time difference of arrival(TDOA) Frequency difference of arrival(FDOA)

The Missing Time Calculation of the Hiatus Surface:A Case Study of the Upper Permian Reef Section the Platform Margin, Ziyun, Guizhou

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Acta Geologica Sinica(English Edition) 1997年第3期71卷 244-256页

作者： Zhou Yaoqi Lu Yongchao Li sitian and wang Hongzhen China University of Petroleum, Dongying, Shandong China University of Geosciences, Beijing Fei Zhenbi China University of Petroleum Dongying Shandong China University of Geosciences Beijing [?]Zhou Yaoqi Born in 1963 studied for his master and doctor degrees at the Institute of High-Energy Physics Chinese Academy of Sciences in 1987–1993 worked in the postdoctoral mobile station of China University of Geosciences (Beijing) in 1993–1995 now professor and director of the Institute of Petroleum Resources and Environmental Geology China University of Petroleum. His current research interests indude high-resolution sequence stratigraphy and basin dynamics.

Taken as an example the Upper Permian reef section on the carbonate platformmargin at Ziyun, Guizhou, the paper discusses the missing time of a hiatus surface, an impor-tant problem in chemical sequence stratigraphy, with the concept of cosmic chemistry. Then thepaper proposes a series of new concepts for chemical sequence stratigraphy, including the con-densation surface, relative compaction factor and time missing factor. Finally a quantitativecurve of Late Permian relative sea-level change in the Ziyun area is presented with timecoordinates.

关键词： chemical sequence stratigraphy hiatus surface reef on platform margin time missing factor relative sea-level change

Study on Basin-Filling and Reservoir Sedimentology of Zhu Ⅲ Depression of Pearl River Mouth Basin,South China Sea

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Journal of Earth Science 2000年第1期19卷 39-48页

作者： Nie Fengjun Department of Energy Resources, China University of Geosciences, Beijing 10008 Li sitian Xie Xinong wang Hua Faculty of Earth Resources, China University of Geosciences, Wuhan 430074 Zhu Weilin China National Offshore Oil Corporat

Through basin-filling analysis, one coarsening-upward and two fining-upward sequences have been identified in Zhu Ⅲ depression. In accondance with the general model proposed by Ravnas and Steel (1998), the basin-filling has two large cycles—rift (sediment-balanced and -overfilled) and postrift (sedimentunderfilled and starved). During the rifting process, the rifted lake developed through three stages: early, climax and late. The sedimentary characteristics of reservoir rocks show that barrier bar, lagoon and tidal channel facies well developed in Zhuhai Formation; offshore, tidal and barrier bar well developed in Zhujiang Formation. Neighborly, Shenhu, Wenchang and Enping formations deposited in rifted lakes during Paleogene time; Zhujiang Formation deposited in bay, lagoon and shoreface in late Paleogene. Zhujiang and other formations deposited in offshore and open shallow sea to shelf.

关键词： Zhu Ⅲ depression basin-fill reservoir rock facies environment.

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妥卡替尼的合成

精细化工 2022年第9期39卷 1894-1900页

作者：黄加香刘洋王巳天赵圣印东华大学化学化工与生物工程学院上海201620

以2-氨基-4-氯吡啶为起始原料,经过缩合、取代、环合、乌尔曼反应和水合肼还原硝基5步反应得到中间体4-([1,2,4]三唑并[1,5-a]吡啶-7-氧基)-3-甲基苯胺(Ⅷ)。2-氨基-5-硝基苯腈先与N,N-二甲基甲酰胺二甲基缩醛(DMF-DMA)缩合,再与4-([1,2... 详细信息

以2-氨基-4-氯吡啶为起始原料,经过缩合、取代、环合、乌尔曼反应和水合肼还原硝基5步反应得到中间体4-([1,2,4]三唑并[1,5-a]吡啶-7-氧基)-3-甲基苯胺(Ⅷ)。2-氨基-5-硝基苯腈先与N,N-二甲基甲酰胺二甲基缩醛(DMF-DMA)缩合,再与4-([1,2,4]三唑并[1,5-a]吡啶-7-氧基)-3-甲基苯胺环合得到N-[3-甲基-4-([1,2,4]三唑并[1,5-a]吡啶-7-氧基)苯基]-6-硝基-4-喹唑啉胺(ⅩⅦ),再经硝基还原得到N^(4)-[3-甲基-4-([1,2,4]三唑并[1,5-a]吡啶-7-氧基)苯基]-4,6-喹唑啉二胺(ⅩⅧ)。同时,采用二硫化碳和2-氨基-2-甲基-1-丙醇为原料,经两步反应制备4,5-二氢-4,4-二甲基-2-(甲硫基)唑三氟甲磺酸盐,收率68.6%。最后,N^(4)-[3-甲基-4-([1,2,4]三唑并[1,5-a]吡啶-7-氧基)苯基]-4,6-喹唑啉二胺和4,5-二氢-4,4-二甲基-2-(甲硫基)唑三氟甲磺酸盐以三乙胺为碱进行缩合反应得到妥卡替尼,收率62.8%,HPLC纯度99.08%。采用~1HNMR、CNMR和HRMS对产物结构进行了表征。

关键词：妥卡替尼酪氨酸激酶抑制剂乳腺癌改进工艺医药原料

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颈动脉血流动力学指标变异度联合被动抬腿试验预测剖宫产术患者腰麻后SHS的准确性

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中华麻醉学杂志 2021年第10期41卷 1180-1183页

作者：王思恬杨柳青王骁颖高巨扬州大学临床医学院(江苏省苏北人民医院)麻醉科 225001

目的评价颈动脉超声测量的血流动力学指标变异度联合被动抬腿试验(PLR)预测剖宫产术患者腰麻后仰卧位低血压综合征(SHS)的准确性。方法择期剖宫产术患者64例,单胎、孕37~42周,年龄18~40岁,BMI 18~30 kg/m2,ASA分级Ⅰ或Ⅱ级。采用超声测... 详细信息

目的评价颈动脉超声测量的血流动力学指标变异度联合被动抬腿试验(PLR)预测剖宫产术患者腰麻后仰卧位低血压综合征(SHS)的准确性。方法择期剖宫产术患者64例,单胎、孕37~42周,年龄18~40岁,BMI 18~30 kg/m2,ASA分级Ⅰ或Ⅱ级。采用超声测量PLR前后的颈动脉直径、血流速度时间积分和血流量的变异度(ΔD、ΔVTI和ΔCBF)。根据是否发生腰麻后SHS将患者分为SHS组和非SHS组(NSHS组)。分析SHS组ΔD、ΔVTI和ΔCBF与腰麻后SBP的相关性。采用受试者工作特征(ROC)曲线评价ΔD、ΔVTI和ΔCBF预测腰麻后SHS的准确性。结果SHS组ΔVTI和腰麻后SBP呈负相关(r=-0.539,P0.05)。ΔCBF、ΔVTI和ΔD联合PLR预测腰麻后SHS的临界值分别为15.5%、10.1%和6.0%,灵敏度分别为92.9%、57.1%和96.4%,特异度分别为53.1%、81.2%和75.0%,曲线下面积分别为0.873、0.681和0.846。结论超声测量的颈动脉ΔCBF和ΔD联合PLR可作为预测剖宫产术患者腰麻后SHS的可靠方法,且ΔCBF联合PLR准确性更高。

关键词：颈动脉血流动力学剖宫产术麻醉,脊椎低血压超声检查被动抬腿试验

颈动脉校正流动时间对产妇蛛网膜下腔麻醉后仰卧位低血压综合征的预测价值

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国际麻醉学与复苏杂志 2021年第9期42卷 912-917页

作者：王思恬高巨罗超王骁颖江苏省苏北人民医院麻醉科扬州大学临床医学院225001

目的探讨并比较超声测量颈动脉校正流动时间(carotid artery corrected flow time,cFT)和颈动脉峰值流速变异度(respirophasic variation in carotid artery blood flow peak velocity,ΔVpeak)对剖宫产产妇蛛网膜下腔麻醉后仰卧位低血压综合征(supine hypotensive syndrome,SHS)的预测价值。方法纳入择期剖宫产单胎产妇60例,年龄18~40岁,ASA分级Ⅰ或Ⅱ级,孕37~42周。根据产妇蛛网膜下腔麻醉后是否发生SHS分为两组:发生SHS组(S组,28例)和未发生SHS组(W组,32例)。记录两组产妇蛛网膜下腔麻醉前后的SBP、DBP、心率,超声测量蛛网膜下腔麻醉前后的cFT、ΔVpeak和颈动脉直径(diameter,D)。采用Pearson相关分析探讨cFT、ΔVpeak与蛛网膜下腔麻醉后SBP的关系,绘制cFT和ΔVpeak判断容量变化的受试者操作特征(receiver operating characteristic,ROC)曲线,计算临界值、曲线下面积(area under curve,AUC)及其95%CI。结果蛛网膜下腔麻醉后有28例(46.7%)产妇发生SHS。与W组比较,S组蛛网膜下腔麻醉后SBP明显降低、心率明显增快(P0.05)。S组蛛网膜下腔麻醉前cFT和蛛网膜下腔麻醉后SBP呈明显的线性正相关性(r=0.563,P0.05)。蛛网膜下腔麻醉前cFT和ΔVpeak预测蛛网膜下腔麻醉后SHS的临界值分别为310.4 ms、10.5%,敏感度分别为85.2%、75.9%,特异性分别为80.4%、90.1%,AUC分别为0.879(95%CI 0.763~0.994)、0.793(95%CI 0.642~0.943)。结论蛛网膜下腔麻醉前超声测量cFT和ΔVpeak可以作为预测产妇蛛网膜下腔麻醉后SHS的可靠指标,且cFT准确性更高。

关键词：超声产妇颈动脉校正流动时间仰卧位低血压综合征

氨基功能化硅酸盐固载磷钨酸催化制备生物柴油及动力学研究

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中国粮油学报 2024年第2期39卷 149-156页

作者：蒋胜筹王婕曾智炜郏俊浩任佳益端木佳辉汪思田韩晓祥浙江工商大学食品与生物工程学院杭州310018

以介孔硅酸盐(TUD-1)为载体,经氨基功能化、磷钨酸固载化制备介孔硅酸盐固载磷钨酸催化剂(TUD-1-NH_(2)-PW),并利用XPS、XRD、TGA-DTG、BET、正丁胺电位滴定法等技术手段与方式对催化剂的结构和酸性进行表征,同时考察该催化剂在催化棕... 详细信息

以介孔硅酸盐(TUD-1)为载体,经氨基功能化、磷钨酸固载化制备介孔硅酸盐固载磷钨酸催化剂(TUD-1-NH_(2)-PW),并利用XPS、XRD、TGA-DTG、BET、正丁胺电位滴定法等技术手段与方式对催化剂的结构和酸性进行表征,同时考察该催化剂在催化棕榈酸与乙醇酯化制备生物柴油反应中的催化性能。研究结果表明,TUD-1-NH2-PW催化剂具有较好的催化酯化活性和稳定性。利用响应面分析法优化所得生物柴油的产率为96.86%,结果与模型预测值基本符合。优化条件下,合成生物柴油的反应级数为1.94,表观活化能为28.10 kJ/mol,动力学方程为:r=-dC_(A)/dt=3.82×10^(2)exp(-28.10/RT)C_(A)^(1.94)。

关键词：生物柴油磷钨酸响应面法动力学研究

Hydrofracturing and episodic compaction of muddy rocks in sedimentary basin

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Chinese Science Bulletin 1998年第8期43卷 666-669页

作者： Xinong Xie Chiyun wang sitian Li China Univ Geosci Fac Earth Resources Wuhan 430074 Peoples R China Univ Calif Berkeley Berkeley CA 94720 USA

Hydrofracturing has been found in a numbr of sedimentary basins throughout the world, which pay an important role in the migration of hydrocarbon and compaction of deposits in overpressured impermeable muddy rock. The forming processes of hydrofracture in the basin evolution has been simulated and the associated episodic compaction of deposits has been evaluated. The modelling results indicate that episodic compacting process in impermeable rocks induced by hydrofracturing is an important way of sediment compaction.

关键词： basin modeling abnormal fluid pressure episodic compaction

颊针联合颈椎功能康复训练在神经根型颈椎病患者中的应用研究

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反射疗法与康复医学 2024年第11期5卷 1-5页

作者：刘奕君陈远陆桥兰王思恬靖江市中医院疼痛科江苏靖江214500

目的研究颊针联合颈椎功能康复训练在神经根型颈椎病患者中的应用效果。方法选择2022年5月—2023年12月靖江市中医院收治的70例神经根型颈椎病患者为研究对象,采用随机数字表法将其分为对照组和研究组,各35例。对照组采用颈椎功能康复... 详细信息

目的研究颊针联合颈椎功能康复训练在神经根型颈椎病患者中的应用效果。方法选择2022年5月—2023年12月靖江市中医院收治的70例神经根型颈椎病患者为研究对象,采用随机数字表法将其分为对照组和研究组,各35例。对照组采用颈椎功能康复训练治疗,研究组在对照组基础上联合颊针治疗。比较两组的临床疗效、颈椎生理曲度和疼痛程度、颈椎关节功能恢复情况及不良事件发生情况。结果研究组治疗总有效率为94.29%,高于对照组的68.57%,差异有统计学意义(P<0.05)。治疗后,研究组Borden氏测量值为(7.36±1.52)mm,高于对照组的(5.28±1.14)mm,疼痛分级指数评分为(2.92±0.75)分,低于对照组的(4.78±1.14)分,组间差异有统计学意义(P<0.05);研究组的生活及工作能力、症状、手功能、体征评分分别为(2.57±0.38)分、(7.24±1.36)分、(-0.78±0.15)分、(6.28±1.75)分,均高于对照组的(2.11±0.29)分、(6.13±1.25)分、(-1.36±0.24)分、(5.19±1.34)分,组间差异有统计学意义(P<0.05)。研究组的不良事件发生率为5.71%,低于对照组的22.86%,差异有统计学意义(P<0.05)。结论颊针联合颈椎功能康复治疗神经根型颈椎病能提升疗效,改善临床症状及颈椎功能,减少不良事件的发生。

关键词：神经根型颈椎病颊针颈椎功能康复训练颈椎生理曲度不良事件