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速度350km/h高速铁路长大下坡地段闭塞分区设置方法研究
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作者 张守帅 张雨洁 +2 位作者 闫海峰 田长海 骆泳吉 《铁道学报》 EI CAS CSCD 北大核心 2024年第1期72-80,共9页
通过分析长大下坡道闭塞分区长度对CTCS-3级和后备CTCS-2级列控系统的影响,指出二者对闭塞分区长度的需求完全相反,并针对CTCS-3级列控系统的行车许可回缩、速度突降等问题的产生原因进行分析。阐述坡度、闭塞分区长度与不同列控模式下... 通过分析长大下坡道闭塞分区长度对CTCS-3级和后备CTCS-2级列控系统的影响,指出二者对闭塞分区长度的需求完全相反,并针对CTCS-3级列控系统的行车许可回缩、速度突降等问题的产生原因进行分析。阐述坡度、闭塞分区长度与不同列控模式下列车运行速度、追踪间隔时间等要素之间的关系,制定闭塞分区设置的基本原则。检算典型坡度下闭塞分区长度设置的合理区间范围及相应追踪间隔时间,指出坡度超过-30‰后将无法兼顾不同列控等级下的运行速度。设计模拟退火算法,根据闭塞分区设置原则及闭塞分区取值规律,给出压缩求解空间、提高求解效率的方法。以郑万高速铁路长大下坡地段为例,对闭塞分区设置进行优化,在不考虑其他约束的前提下,与设计院优化方案相比,本求解优化方案在确保CTCS-3级控车模式下允许速度可达350 km/h的同时,将CTCS-2级控车模式下的允许速度提高30 km/h,追踪间隔时间压缩23 s。 展开更多
关键词 高速铁路 长大下坡道 CTCS-3级列控系统 闭塞分区 行车许可
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Integration of Sequence Stratigraphic Analysis and 3D Geostatistical Modeling of Pliocene–Pleistocene Delta,F3 Block,Netherlands 被引量:1
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作者 Haris Ahmed KHAN Ali Asghar SHAHID +3 位作者 Muhammad Jahangir KHAN Taher ZOUAGHI Maria Dolores ALVAREZ Syed Danial Mehdi NAQVI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期256-268,共13页
This research is focused on the analysis of the sequence stratigraphic units of F3 Block,within a wave-dominated delta of Plio–Pleistocene age.Three wells of F3 block and a 3D seismic data,are utilized in this resear... This research is focused on the analysis of the sequence stratigraphic units of F3 Block,within a wave-dominated delta of Plio–Pleistocene age.Three wells of F3 block and a 3D seismic data,are utilized in this research.The conventional techniques of 3D seismic interpretation were utilized to mark the 11 surfaces on the seismic section.Integration of seismic sequence stratigraphic interpretation,using well logs,and subsequent 3D geostatistical modeling,using seismic data,aided to evaluate the shallow hydrocarbon traps.The resulting models were obtained using System Tract and Facies models,which were generated by using sequential stimulation method and their variograms made by spherical method,moreover,these models are validated via histograms.The CDF curve generated from upscaling of well logs using geometric method,shows a good relation with less percentage of errors(1 to 2 for Facies and 3 to 4 for System Tract models)between upscaled and raw data that complements the resulted models.These approaches help us to delineate the best possible reservoir,lateral extent of system tracts(LST and/or HST)in the respective surface,and distribution of sand and shale in the delta.The clinoform break points alteration observed on seismic sections,also validates the sequence stratigraphic interpretation.The GR log-based Facies model and sequence stratigraphy-based System Tract model of SU-04-2 showed the reservoir characteristics,presence of sand bodies and majorly LST,respectively,mainly adjacent to the main fault of the studied area.Moreover,on the seismic section,SU-04-2 exhibits the presence of gas pockets at the same location that also complements the generated Facies and System Tract models.The generated models can be utilized for any similar kind of study and for the further research in the F3 block reservoir characterization. 展开更多
关键词 sequence stratigraphy facies modeling system tract modeling F3 block North Sea
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猪圆环病毒3型Cap蛋白单克隆抗体的制备及阻断ELISA检测方法的建立 被引量:1
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作者 张宝戈 黄雅琴 +2 位作者 蔡金双 朱晨光 李玉峰 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第3期1170-1178,共9页
旨在建立检测猪圆环病毒3型(PCV3)抗体的阻断ELISA方法,本研究利用原核表达的PCV3Cap重组蛋白免疫BALB/c小鼠制备获得了一株分泌阻断效果良好抗体的杂交瘤细胞株2E6。以重组Cap蛋白作为包被抗原,以辣根过氧化物酶(HRP)标记的2E6单克隆... 旨在建立检测猪圆环病毒3型(PCV3)抗体的阻断ELISA方法,本研究利用原核表达的PCV3Cap重组蛋白免疫BALB/c小鼠制备获得了一株分泌阻断效果良好抗体的杂交瘤细胞株2E6。以重组Cap蛋白作为包被抗原,以辣根过氧化物酶(HRP)标记的2E6单克隆抗体作为检测抗体,经条件优化后建立了一种检测PCV3抗体的阻断ELISA方法。用建立的阻断ELISA方法检测50份临床阴性血清,计算阻断率(PI)的临界值,以此来确定该方法的判定标准:当PI≤28.30%时,判定结果为阴性;当PI≥35.05%时,判定结果为阳性;当28.30%<PI<35.05%时,判定为可疑,重复一次试验后如果结果仍为可疑,则判定为阳性。特异性试验表明该方法与猪圆环病毒2型(PCV2)、猪伪狂犬病病毒(PRV)、猪繁殖与呼吸综合征病毒(PRRSV)以及猪瘟病毒(CSFV)的阳性血清均无交叉反应;敏感性试验表明其检测效价可达到1:128;重复性试验表明批内与批间的变异系数均小于10%;符合性检验表明该方法与PCV检测金标准免疫过氧化物酶单层试验(IPMA)比对的Kappa值达0.9,具有高度的一致性。综上所述,本研究建立的阻断ELISA方法具有良好的特异性与较高的符合率,可用于后期进行PCV3抗体的检测,为PCV3的流行病学调查与临床诊断提供技术支持。 展开更多
关键词 猪圆环病毒3 Cap重组蛋白 单克隆抗体 阻断ELISA
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微流控技术辅助制备多孔石墨相氮化碳(g-C3N4)块体及其性能研究
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作者 马千驰 徐倩鑫 +2 位作者 周何 郝彬琦 常振旗 《现代化工》 CAS CSCD 北大核心 2024年第3期90-96,共7页
设计了适用于微流控系统的原位生成酸催化聚乙烯醇/戊二醛凝胶反应体系并用于g-C_(3)N_(4)多孔微球粒径与形貌的可控制备,以无机粘结剂和多孔微球为原料实现氚兼容的多孔g-C_(3)N_(4)块体的制备。考察了凝胶组成成分、煅烧模式对微球比... 设计了适用于微流控系统的原位生成酸催化聚乙烯醇/戊二醛凝胶反应体系并用于g-C_(3)N_(4)多孔微球粒径与形貌的可控制备,以无机粘结剂和多孔微球为原料实现氚兼容的多孔g-C_(3)N_(4)块体的制备。考察了凝胶组成成分、煅烧模式对微球比表面积与机械强度的影响,以及无机黏合剂质量分数、微球粒径对g-C_(3)N_(4)块体比表面积与机械强度的影响。结果表明,微球粒径对块体材料性能有显著影响,在相同成型黏合剂质量分数下,微球粒径增加79.5%块体材料的比表面积提高205%,而机械强度仅降低了42%。4.5 K低温气体吸附实验结果表明,所制备的g-C_(3)N_(4)多孔块体吸附层对氢气和氦气的选择性系数可达13.02。 展开更多
关键词 g-C_(3)N_(4)多孔微球 多孔g-C_(3)N_(4)块体 比表面积 微流控技术 低温泵
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聚(3-己基噻吩)-聚苯乙烯嵌段共聚物的一锅法制备
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作者 樊亚娟 刘承先 +1 位作者 李东升 刘长春 《合成树脂及塑料》 CAS 北大核心 2023年第4期19-23,共5页
采用具有聚苯乙烯高分子链为配位基团的聚合催化剂,催化2,5-二溴-3-己基噻吩单体进行Kumada缩聚反应,利用一锅法制备了聚(3-己基噻吩)-聚苯乙烯嵌段共聚物。结果表明:采用一锅法,在室温、常压条件下进行一步聚合直接生成嵌段共聚物,反... 采用具有聚苯乙烯高分子链为配位基团的聚合催化剂,催化2,5-二溴-3-己基噻吩单体进行Kumada缩聚反应,利用一锅法制备了聚(3-己基噻吩)-聚苯乙烯嵌段共聚物。结果表明:采用一锅法,在室温、常压条件下进行一步聚合直接生成嵌段共聚物,反应过程简单,聚(3-己基噻吩)与聚苯乙烯嵌段对接率接近100%;与聚(3-己基噻吩)相比,聚(3-己基噻吩)-聚苯乙烯嵌段共聚物的结晶性能更好。 展开更多
关键词 聚(3-己基噻吩) 聚苯乙烯 嵌段共聚物 Kumada缩聚反应
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区组长为4和6的3-设计
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作者 王建 《南通职业大学学报》 2023年第2期64-66,共3页
t-(v,K,λ)设计是一个关联结构(V,B),满足条件:(1)V是v元点集;(2)B是V的子集族(B中的元素称为设计的区组),且每一个区组b∈B有|b|∈K;(3)V中的任意一个t-元子集恰好出现在λ个区组中。Hanani给出了λ=1时3-(v,{4,6},1)存在的充分必要条... t-(v,K,λ)设计是一个关联结构(V,B),满足条件:(1)V是v元点集;(2)B是V的子集族(B中的元素称为设计的区组),且每一个区组b∈B有|b|∈K;(3)V中的任意一个t-元子集恰好出现在λ个区组中。Hanani给出了λ=1时3-(v,{4,6},1)存在的充分必要条件。文章证明3-(v,{4,6},λ)存在的充分必要条件是λv≡0(mod 2),λv(v-1)(v-2)≡0(mod 8)且v≥4。 展开更多
关键词 T-设计 3-设计 区组长为4和6
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Multi-focus image fusion based on block matching in 3D transform domain 被引量:5
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作者 YANG Dongsheng HU Shaohai +2 位作者 LIU Shuaiqi MA Xiaole SUN Yuchao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第2期415-428,共14页
Fusion methods based on multi-scale transforms have become the mainstream of the pixel-level image fusion. However,most of these methods cannot fully exploit spatial domain information of source images, which lead to ... Fusion methods based on multi-scale transforms have become the mainstream of the pixel-level image fusion. However,most of these methods cannot fully exploit spatial domain information of source images, which lead to the degradation of image.This paper presents a fusion framework based on block-matching and 3D(BM3D) multi-scale transform. The algorithm first divides the image into different blocks and groups these 2D image blocks into 3D arrays by their similarity. Then it uses a 3D transform which consists of a 2D multi-scale and a 1D transform to transfer the arrays into transform coefficients, and then the obtained low-and high-coefficients are fused by different fusion rules. The final fused image is obtained from a series of fused 3D image block groups after the inverse transform by using an aggregation process. In the experimental part, we comparatively analyze some existing algorithms and the using of different transforms, e.g. non-subsampled Contourlet transform(NSCT), non-subsampled Shearlet transform(NSST), in the 3D transform step. Experimental results show that the proposed fusion framework can not only improve subjective visual effect, but also obtain better objective evaluation criteria than state-of-the-art methods. 展开更多
关键词 image fusion block matching 3D transform block-matching and 3D(BM3D) non-subsampled Shearlet transform(NSST)
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Comparison between the seismic response of 2D and 3D models of rigid blocks 被引量:3
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作者 Angelo Di Egidio Daniele Zulli Alessandro Contento 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第1期151-162,共12页
A three-dimensional rigid body on the shape of a parallelepiped is modelled in order to rock on a side or a vertex of the base,in order to evaluate the seismic response of rigid blocks lying on a horizontal support.Th... A three-dimensional rigid body on the shape of a parallelepiped is modelled in order to rock on a side or a vertex of the base,in order to evaluate the seismic response of rigid blocks lying on a horizontal support.The center of mass of the body is considered as eccentric with respect to its geometric center.As seismic input,three Italian recorded accelerograms,with different spectral content,are used.The study is mainly conducted to highlight the differences between the seismic response of 2D and 3D models of rigid blocks,with the aim to understand if,in some cases,the use of the 3D model of rigid block is required to obtain safer results.In fact,the outcomes show that in some ranges of the geometrical and mechanical parameters that characterize the excitation and the body,a two-dimensional model,which is not able to consider the 3D rocking on a vertex,can provide unsafe results.In particular,it is found that the overturning process of the three-dimensional block can occur under excitations which are lower than those which overturn a corresponding two-dimensional block. 展开更多
关键词 seismic excitation 3D rigid block rectangular base ROCKING OVERTURNING
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3D Identification and Stability Analysis of Key Surface Blocks of Rock Slope 被引量:4
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作者 李明超 周四宝 王刚 《Transactions of Tianjin University》 EI CAS 2016年第4期317-323,共7页
Complicated geological structures make it difficult to analyze the stability of rock slopes, such as faults, weak intercalated layers or joint fissures. Based on 3D geological modeling and surface block identifying me... Complicated geological structures make it difficult to analyze the stability of rock slopes, such as faults, weak intercalated layers or joint fissures. Based on 3D geological modeling and surface block identifying methods, an integrated methodology framework was proposed and realized to analyze the stability of surface blocks in rock slopes. The surface blocks cut by geological structures, fissures or free faces could be identified subjected to the four principles of closure, completeness, uniqueness and validity. The factor of safety(FOS)of single key block was calculated by the limit equilibrium method. If there were two or more connected blocks, they were defined as a block-group. The FOS of a block-group was computed by the Sarma method. The proposed approach was applied to an actual rock slope of a hydropower project, and some possible instable blocks were demonstrated and analyzed visually. The obtained results on the key blocks or block-groups provide essential information for determining potential instable region of rock slopes and designing effective support scheme in advance. 展开更多
关键词 rock slope 3D model surface block block-group stability factor of safety(FOS)
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Study on the Influence of Piloti on Mean Radiant Temperature in Residential Blocks by 3-D Unsteady State Heat Balance Radiation Calculation 被引量:1
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作者 Tian-Yu Xi Jian-Hua Ding Hong Jin 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第4期91-95,共5页
Piloti is commonly used in tropical and subtropical climate zones to get high wind velocity and create shadowed areas in order to optimize the living environment of residential blocks,but there are few studies to reve... Piloti is commonly used in tropical and subtropical climate zones to get high wind velocity and create shadowed areas in order to optimize the living environment of residential blocks,but there are few studies to reveal the influence of piloti on the radiant environment of residential blocks systematically. Taking the city of Guangzhou as an example,using 3-D Unsteady State Heat Balance Radiation Calculation Method,this paper shows that the mean radiant temperature( MRT) under piloti area increases with the increase of piloti ratio,and especially when piloti ratio is equal to 100%,the MRT increase trend becomes sharp. The MRT of exposed area decreases with the increase of piloti ratio,especially when piloti ratio reaches 100%,the decrease trend of MRT becomes sharp,which offers the reference for the study on piloti design in subtropical climate zones and further research on living environment by CFD simulation in residential blocks. 展开更多
关键词 piloti mean radiant temperature 3-D unsteady state heat balance radiation calculation residential block
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基于CTCS-3/2级列控系统的高速铁路闭塞分区长度设计研究 被引量:1
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作者 耿敬春 李建新 +2 位作者 吕苗苗 倪少权 潘金山 《铁道学报》 EI CAS CSCD 北大核心 2023年第4期8-15,共8页
根据CTCS-3级和CTCS-2级列控车载设备控车原理,提出高速铁路闭塞分区长度设计原则和约束条件。结合现行列控车载设备参数,当线路长大下坡道不大于24‰时,闭塞分区长度设计满足CTCS-3级列控车载顶棚速度350 km/h、CTCS-2级300 km/h正常... 根据CTCS-3级和CTCS-2级列控车载设备控车原理,提出高速铁路闭塞分区长度设计原则和约束条件。结合现行列控车载设备参数,当线路长大下坡道不大于24‰时,闭塞分区长度设计满足CTCS-3级列控车载顶棚速度350 km/h、CTCS-2级300 km/h正常运行。当线路长大下坡道大于24‰时,闭塞分区长度按照满足CTCS-3级列控车载顶棚速度350 km/h、CTCS-2级降速至250 km/h设计;或将CTCS-3级列控系统结合轨道电路信息定义的闭塞分区平均长度由3000 m调整为4400 m,以满足CTCS-3级列控车载顶棚速度350 km/h、CTCS-2级300 km/h运行要求。 展开更多
关键词 高速铁路 CTCS-3/2级列控系统 闭塞分区 长度 设计
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Integrating artificial neural networks and geostatistics for optimum 3D geological block modeling in mineral reserve estimation:A case study 被引量:2
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作者 Jalloh Abu Bakarr Kyuro Sasaki +1 位作者 Jalloh Yaguba Barrie Abubakarr Karim 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期581-585,共5页
In this research, a method called ANNMG is presented to integrate Artificial Neural Networks and Geostatistics for optimum mineral reserve evaluation. The word ANNMG simply means Artificial Neural Network Model integr... In this research, a method called ANNMG is presented to integrate Artificial Neural Networks and Geostatistics for optimum mineral reserve evaluation. The word ANNMG simply means Artificial Neural Network Model integrated with Geostatiscs, In this procedure, the Artificial Neural Network was trained, tested and validated using assay values obtained from exploratory drillholes. Next, the validated model was used to generalize mineral grades at known and unknown sampled locations inside the drilling region respectively. Finally, the reproduced and generalized assay values were combined and fed to geostatistics in order to develop a geological 3D block model. The regression analysis revealed that the predicted sample grades were in close proximity to the actual sample grades, The generalized grades from the ANNMG show that this process could be used to complement exploration activities thereby reducing drilling requirement. It could also be an effective mineral reserve evaluation method that could oroduce optimum block model for mine design. 展开更多
关键词 Artificial Neural Network Model withGeostatistics (ANNMG)3D geological block modeling Mine designKriging
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3-D crustal-scale gravity model of the San Rafael Block and Payenia volcanic province in Mendoza,Argentina
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作者 Daniel Richarte Marianela Lupari +2 位作者 Agustina Pesce Silvina Nacif Mario Gimenez 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第1期239-248,共10页
The San Rafael Block(SRB)is part of one of the main retroarc volcanic provinces in southern Central Andes in Mendoza,Argentina.This block is located in the Andean foothills between the orogenic front and foreland base... The San Rafael Block(SRB)is part of one of the main retroarc volcanic provinces in southern Central Andes in Mendoza,Argentina.This block is located in the Andean foothills between the orogenic front and foreland basement uplifts of late Miocene age.In order to analyze the geochronological evolution of the Quaternary volcanism in the region,several geologic and geophysical studies have been conducted.Nevertheless,the crust,where the SRB is located,has not been well characterized yet.Based on gravimetric and magnetic data,together with isostatic and elastic thickness analyses,we modeled the crustal structure of the area.Information obtained has allowed us to understand the crust where the SRB and the Payenia volcanic province are located.Bouguer anomalies indicate that the SRB presents higher densities to the North of Cerro Nevado and Moho calculations suggest depths for this block between 40 and 50 km.Determinations of elastic thickness would indicate that the crust supporting the San Rafael Block presents values of approximately 10 km,being enough to support the block loading.However,in the Payenia region,elastic thickness values are close to zero due to the regional temperature increase. 展开更多
关键词 SAN Rafael block Payenia 3-D CRUSTAL model Asthenospheric wedge
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Comparison between Plane and Stereo Block Adjustment for ZY-3 Satellite Images 被引量:1
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作者 Taoyang WANG Guo ZHANG +3 位作者 Deren LI Wanshou JIANG Xinming TANG Xuelin LIU 《Journal of Geodesy and Geoinformation Science》 2018年第1期53-60,共8页
Block adjustment for satellite images cannot be solved with weak convergence geometric conditions,therefore a plane block adjustment method to improve the targeting precision of images is proposed utilizing DEM as hei... Block adjustment for satellite images cannot be solved with weak convergence geometric conditions,therefore a plane block adjustment method to improve the targeting precision of images is proposed utilizing DEM as height constraint plane block adjustment method.First,a rational function model with affine transformation is selected as the mathematical model of the satellite image plane block adjustment.Second,to update the ground coordinates of tie points(TPs),the plane coordinates of TPs are only solved in the adjustment process.Elevation values are obtained by using DEM interpolation.Finally,the plane coordinates of all TPs and orientation parameters of all satellite images are solved through plane block adjustment with a few ground control points ZY-3 nadir images for two regions are tested for plane block adjustment while ZY-3 forward-nadir-back images of the same two regions are tested for stereo block adjustment.A comparison indicates that almost the same accuracy can be obtained with plane block adjustment support using a 1∶50 000 DEM and stereo block adjustment for ZY-3 images.For ZY-3 nadir images,almost no loss of plane block adjustment accuracy occurred when global DEM with 1 km grid and SRTM with 90 m grid replaced the 1∶50 000 DEM as elevation control,.Test results demonstrate the effectiveness and feasibility of the plane block adjustment method. 展开更多
关键词 ZY-3 SATELLITE IMAGES STEREO block adjustment PLANE block adjustment ACCURACY
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SYNTHESIS OF NOVEL BLOCK COPOLYMERS OF POLY(3-HYDROXYBUTYRIC ACID)WITH POLY(ETHYLENE GLYCOL)THROUGH ANIONIC POLYMERISATION
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作者 Xin-tao Shuai Zbigniew Jedlinski +1 位作者 Qiang Luo Nozirow Farhod Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China Institute of Polymer Chemistry, Polish Academy of Sciences, 41-800 Zabrze, Poland Institute of Synthetic Fibre, Chinese Academy of Textile Sciences, Beijing 100025, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2000年第1期19-23,共5页
A novel kind of copolymer with ABA-type block structure was synthesized by anionic ring-opening polymerization of beta-butyrolactone (beta-BL) in the presence of a PEG-based dicarboxylates as macroinitiators which wer... A novel kind of copolymer with ABA-type block structure was synthesized by anionic ring-opening polymerization of beta-butyrolactone (beta-BL) in the presence of a PEG-based dicarboxylates as macroinitiators which were prepared by the esterification of aliphatic cyclic anhydride and poly(ethylene glycol) (PEG) oligomers (M-n = 2000, 4000 and 6000) and conversion of potassium dicarboxylates. The resultant copolymers as well as the intermediates were characterized by IR, H-1-NMR and GPC. 展开更多
关键词 block copolymer poly(ethylene glycol) poly(3-hydroxybutyric acid)
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Two Chiral Building Blocks for the Stereocontrolled Synthesis of Anti-and Syn-1,3-Diols
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作者 Yong WU Mei GUAN +2 位作者 Zheng XU Li Cheng Xiao Chun WU 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第9期765-766,共2页
Two chiral building blocks 1 and 2 for anti-and syn-1, 3-diols has been achieved in 8 steps and 7 steps respectively, starting from the readily available and inexpensive D (+)-xylose 3.
关键词 Chiral building block anti-and syn-1 3-diols D (+)-xylose
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Ethyl 2-diazo-3-oxo-perfluorocarboxylates as a Potentially Fluorine-containing Building Block:[Rh(OAc)_2]_2-Catalyzed Reaction with Nitriles
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期241-241,共1页
关键词 Rh OAC Ethyl 2-diazo-3-oxo-perfluorocarboxylates as a Potentially Fluorine-containing Building block Catalyzed Reaction with Nitriles
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(Z)-ETHYL 3-BROMO-4,4,4-TRIFLUORO-2-BUTENOATE AS A NOVEL CF_3-CONTAINING BUILDING BLOCK: Its Preparation and Pd-Catalysed Reaction with Alkynes and Organozinc Reagents
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作者 Wei Yuan HUANG, Long Lǔ Shanghai Institute of Organic Chemistry, The Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第10期769-772,共4页
A novel CF_3-containing building block, (Z)-ethyl 3-bromo-4,4,4-trifluoro-2-butenoate, was easily prepared from CF_3CBr_3, the former reacted with alkynes Or organozinc reagents in the presence of Pd complexes to affo... A novel CF_3-containing building block, (Z)-ethyl 3-bromo-4,4,4-trifluoro-2-butenoate, was easily prepared from CF_3CBr_3, the former reacted with alkynes Or organozinc reagents in the presence of Pd complexes to afford useful CF_3-containing intermediates in good yield. 展开更多
关键词 CF Br ETHYL 3-BROMO-4 4 4-TRIFLUORO-2-BUTENOATE AS A NOVEL CF3-CONTAINING BUILDING block Its Preparation and Pd-Catalysed Reaction with Alkynes and Organozinc Reagents PD AS
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Preparation and Stereospecified Suzuki Reaction of a Resin Bound CF_3-Containing Building Block
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期310-310,共1页
关键词 CF Preparation and Stereospecified Suzuki Reaction of a Resin Bound CF3-Containing Building block
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右美托咪定复合罗哌卡因髂筋膜间隙阻滞用于老年髋关节置换术的镇痛效果及对PI3K-Akt信号通路的影响 被引量:3
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作者 张倍倍 张爽 +2 位作者 陈钱正 刁寒 殷庆堂 《临床和实验医学杂志》 2023年第17期1901-1904,F0003,共5页
目的研究右美托咪定复合罗哌卡因髂筋膜间隙阻滞用于老年髋关节置换术的镇痛效果及对磷脂酰肌醇3激酶(PI3K)-蛋白激酶B(Akt)信号通路的影响。方法前瞻性选取2020年5月至2022年5月于南通市海门区人民医院接受髋关节置换术治疗的患者100例... 目的研究右美托咪定复合罗哌卡因髂筋膜间隙阻滞用于老年髋关节置换术的镇痛效果及对磷脂酰肌醇3激酶(PI3K)-蛋白激酶B(Akt)信号通路的影响。方法前瞻性选取2020年5月至2022年5月于南通市海门区人民医院接受髋关节置换术治疗的患者100例,按随机数字表法将其分为观察组和对照组,每组各50例。两组患者均行髋关节置换术,对照组患者行罗哌卡因髂筋膜间隙阻滞,观察组患者行右美托咪定复合罗哌卡因髂筋膜间隙阻滞。比较两组围手术期指标、血流动力学(心率、舒张压、收缩压)、镇痛效果[视觉模拟评分法(VAS)评分、Ramsay镇静评分]、认知功能[简易智能精神状态检查(MMSE)量表]、PI3K-Akt信号通路标志性蛋白(PI3K、Akt)表达水平及不良反应发生情况。结果两组手术时间、麻醉时间比较,差异均无统计学意义(P>0.05),观察组术中出血量、输液量均低于较对照组,差异均有统计学意义(P<0.05)。观察组麻醉诱导后5 min、插管、拔管时心率、收缩压、舒张压均低于对照组,差异均有统计学意义(P<0.05)。术后2、6、12 h,观察组的VAS评分分别为(1.23±0.17)、(3.02±0.43)、(3.16±0.44)分,均低于对照组[(1.43±0.20)、(3.47±0.48)、(3.61±0.51)分],Ramsay镇静评分分别为(2.17±0.31)、(2.96±0.42)、(3.49±0.49)分,均高于对照组[(1.83±0.26)、(2.14±0.30)、(2.91±0.41)分],差异均有统计学意义(P<0.05)。术后1、3、7 d,观察组认知功能评分分别为(27.58±3.94)、(28.63±4.09)、(29.16±4.15)分,均高于对照组[(24.13±3.30)、(24.70±3.37)、(25.05±3.61)分],差异均有统计学意义(P<0.05)。术后6、12 h,观察组PI3K蛋白表达水平分别为0.90±0.13、0.79±0.11,Akt蛋白表达水平分别为1.09±0.15、1.10±0.15,均高于对照组(0.73±0.10、0.65±0.09和0.91±0.13、0.94±0.14),差异均有统计学意义(P<0.05)。两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论右美托咪定复合罗哌卡因髂筋膜间隙阻滞用于老年髋关节置换术具有出血量、输液量较少的优势,同时能使术中血流动力学维持稳定,降低术后疼痛,对PI3K-Akt信号通路有一定调节作用。 展开更多
关键词 髋关节 麻醉和镇痛 磷脂酰肌醇3激酶 右美托咪定 髂筋膜间隙阻滞 蛋白激酶B
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