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一种MAKLINK图多节点链路建模的路径规划研究
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作者 孙培刚 张全禹 许春和 《电子设计工程》 2024年第4期140-143,148,共5页
针对传统MAKLINK图规划路径线路改变时,其最优化路径易与环境约束条件冲突的问题,提出了在MAKLINK图中各链路上增加节点数目的方法,以提高系统建模的适应性和鲁棒性。设计的多节点链路通过dijkstra算法得到更为理想的次优化路径,由蚁群... 针对传统MAKLINK图规划路径线路改变时,其最优化路径易与环境约束条件冲突的问题,提出了在MAKLINK图中各链路上增加节点数目的方法,以提高系统建模的适应性和鲁棒性。设计的多节点链路通过dijkstra算法得到更为理想的次优化路径,由蚁群算法进行迭代计算获得最优化路径,实现了在保证路径适应度的前提下,提高优化路径对环境约束条件的适应性。实验结果表明,与基本MAKLINK图路径规划算法相比,多节点链路的建模路径规划算法可有效提高次优路径的建模精度,最优路径的适应度值较单节点链路减小了1.43%,具有一定的建模优势。 展开更多
关键词 MAKlink 多节点链路 DIJKSTRA算法 蚁群算法
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一种改进的Link16信号检测方法
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作者 薛燕 高春芳 杨欣 《现代雷达》 CSCD 2024年第1期39-44,共6页
直接序列扩频、高速跳频与跳时相结合的技术,造成了对Link16信号的检测具有相当的难度。文中针对突发Link16信号脉冲宽度强规律性,借鉴双滑动窗算法在突发信号检测上的应用,提出了改进后基于相关处理的双滑动窗Link16信号检测方法,该方... 直接序列扩频、高速跳频与跳时相结合的技术,造成了对Link16信号的检测具有相当的难度。文中针对突发Link16信号脉冲宽度强规律性,借鉴双滑动窗算法在突发信号检测上的应用,提出了改进后基于相关处理的双滑动窗Link16信号检测方法,该方法可实现复杂电磁环境下对Link16信号的高灵敏度、高概率检测,同时正确估算出脉宽、码速率等参数信息。仿真实验数据验证了理论分析的正确性和所述方法的有效性,相较于其他Link16信号检测方法,改进后的基于相关处理的双滑动窗检测算法明显提高了在低信噪比下对Link16信号的检测能力。 展开更多
关键词 link16信号 双窗滑动相关 突发信号检测
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基于GS1 Digital Link的Web编码构建与案例应用
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作者 王少然 李小英 韩英玉 《保鲜与加工》 CAS 2024年第4期49-53,60,共6页
为探索GS1 Digital Link技术在产品物流中的应用潜力,分析研究了GS1系统和GS1 Digital Link的基本结构、编码特点以及技术优势,充分利用GS1 Digital Link技术可以为产品从源头到零售整个物流过程提供相关对象的Web地址编码的特点,以鲜... 为探索GS1 Digital Link技术在产品物流中的应用潜力,分析研究了GS1系统和GS1 Digital Link的基本结构、编码特点以及技术优势,充分利用GS1 Digital Link技术可以为产品从源头到零售整个物流过程提供相关对象的Web地址编码的特点,以鲜活大闸蟹物流过程为例,构建了基于GS1 Digital Link的鲜活大闸蟹Web编码,为实现产品营销与追溯提供了标准化、动态化、多样化的编码数据支撑。 展开更多
关键词 GS1 GS1 Digital link 标准化 物流 编码 标识
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Dilation,discrimination and Uhlmann's theorem of link products of quantum channels
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作者 雷强 操刘桁 +1 位作者 Asutosh Kumar 武俊德 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期201-206,共6页
We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-l... We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-linking each quantum channel n times as n grows.We also find that the maximum value of Uhlmann's theorem can be achieved for diagonal channels. 展开更多
关键词 quantum channels link products Stinespring dilation theorem Uhlmann's theorem
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Layered Coded Cache Placement and Cooperative Delivery with Sharing Links in Satellite-Terrestrial Integrated Networks
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作者 Gu Shushi Chen Zihan +2 位作者 Wu Yaonan Zhang Qinyu Wang Ye 《China Communications》 SCIE CSCD 2024年第3期217-229,共13页
Cooperative utilization of multidimensional resources including cache, power and spectrum in satellite-terrestrial integrated networks(STINs) can provide a feasible approach for massive streaming media content deliver... Cooperative utilization of multidimensional resources including cache, power and spectrum in satellite-terrestrial integrated networks(STINs) can provide a feasible approach for massive streaming media content delivery over the seamless global coverage area. However, the on-board supportable resources of a single satellite are extremely limited and lack of interaction with others. In this paper, we design a network model with two-layered cache deployment, i.e., satellite layer and ground base station layer, and two types of sharing links, i.e., terrestrial-satellite sharing(TSS) links and inter-satellite sharing(ISS) links, to enhance the capability of cooperative delivery over STINs. Thus, we use rateless codes for the content divided-packet transmission, and derive the total energy efficiency(EE) in the whole transmission procedure, which is defined as the ratio of traffic offloading and energy consumption. We formulate two optimization problems about maximizing EE in different sharing scenarios(only TSS and TSS-ISS),and propose two optimized algorithms to obtain the optimal content placement matrixes, respectively.Simulation results demonstrate that, enabling sharing links with optimized cache placement have more than 2 times improvement of EE performance than other traditional placement schemes. Particularly, TSS-ISS schemes have the higher EE performance than only TSS schemes under the conditions of enough number of satellites and smaller inter-satellite distances. 展开更多
关键词 coded content placement cooperative delivery energy efficiency sharing links STINs
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Robust free-space optical frequency transfer in time-varying link distances conditions
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作者 童周 刘雷 +6 位作者 王家亮 操前 金志成 应康 韩申生 韩正甫 桂有珍 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期271-276,共6页
Future inter-satellite clock comparison on high orbit will require optical time and frequency transmission technology between moving objects.Here,we demonstrate robust optical frequency transmission under the conditio... Future inter-satellite clock comparison on high orbit will require optical time and frequency transmission technology between moving objects.Here,we demonstrate robust optical frequency transmission under the condition of variable link distance.This variable link is accomplished by the relative motion of a single telescope fixed on the experimental platform to a corner-cube reflector(CCR)installed on a sliding guide.Two acousto–optic modulators with different frequencies are used to separate forward signal from backward signal.With active phase noise suppression,when the CCR moves back and forth at a constant velocity of 20 cm/s and an acceleration of 20 cm/s^(2),we achieve the best frequency stability of 1.9×10^(-16) at 1 s and 7.9×10^(-19) at 1000 s indoors.This work paves the way for future studying optical frequency transfer between ultra-high-orbit satellites. 展开更多
关键词 FREE-SPACE optical frequency transfer variable link distance
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Coherent optical frequency transfer via 972-km fiber link
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作者 邓雪 张翔 +8 位作者 臧琦 焦东东 王丹 刘杰 高静 许冠军 董瑞芳 刘涛 张首刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期277-282,共6页
We demonstrate coherent optical frequency dissemination over a distance of 972 km by cascading two spans where the phase noise is passively compensated for.Instead of employing a phase discriminator and a phase lockin... We demonstrate coherent optical frequency dissemination over a distance of 972 km by cascading two spans where the phase noise is passively compensated for.Instead of employing a phase discriminator and a phase locking loop in the conventional active phase control scheme,the passive phase noise cancellation is realized by feeding double-trip beat-note frequency to the driver of the acoustic optical modulator at the local site.This passive scheme exhibits fine robustness and reliability,making it suitable for long-distance and noisy fiber links.An optical regeneration station is used in the link for signal amplification and cascaded transmission.The phase noise cancellation and transfer instability of the 972-km link is investigated,and transfer instability of 1.1×10^(-19)at 10^(4)s is achieved.This work provides a promising method for realizing optical frequency distribution over thousands of kilometers by using fiber links. 展开更多
关键词 optical frequency transfer fiber link phase noise cancellation
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Underwater Image Classification Based on EfficientnetB0 and Two-Hidden-Layer Random Vector Functional Link
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作者 ZHOU Zhiyu LIU Mingxuan +2 位作者 JI Haodong WANG Yaming ZHU Zefei 《Journal of Ocean University of China》 CAS CSCD 2024年第2期392-404,共13页
The ocean plays an important role in maintaining the equilibrium of Earth’s ecology and providing humans access to a wealth of resources.To obtain a high-precision underwater image classification model,we propose a c... The ocean plays an important role in maintaining the equilibrium of Earth’s ecology and providing humans access to a wealth of resources.To obtain a high-precision underwater image classification model,we propose a classification model that combines an EfficientnetB0 neural network and a two-hidden-layer random vector functional link network(EfficientnetB0-TRVFL).The features of underwater images were extracted using the EfficientnetB0 neural network pretrained via ImageNet,and a new fully connected layer was trained on the underwater image dataset using the transfer learning method.Transfer learning ensures the initial performance of the network and helps in the development of a high-precision classification model.Subsequently,a TRVFL was proposed to improve the classification property of the model.Net construction of the two hidden layers exhibited a high accuracy when the same hidden layer nodes were used.The parameters of the second hidden layer were obtained using a novel calculation method,which reduced the outcome error to improve the performance instability caused by the random generation of parameters of RVFL.Finally,the TRVFL classifier was used to classify features and obtain classification results.The proposed EfficientnetB0-TRVFL classification model achieved 87.28%,74.06%,and 99.59%accuracy on the MLC2008,MLC2009,and Fish-gres datasets,respectively.The best convolutional neural networks and existing methods were stacked up through box plots and Kolmogorov-Smirnov tests,respectively.The increases imply improved systematization properties in underwater image classification tasks.The image classification model offers important performance advantages and better stability compared with existing methods. 展开更多
关键词 underwater image classification EfficientnetB0 random vector functional link convolutional neural network
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电动汽车电控液压制动系统CarSim/Simulink联合仿真研究
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作者 洪诚 李琤 《汽车实用技术》 2024年第5期52-58,共7页
针对某款国产电动汽车的电控液压制动系统,文章基于滑移率的比例-积分-微分(PID)控制提出了防抱死制动系统(ABS)模型,以改善车辆制动性能,提高在对开路面上的制动有效性和安全性。首先,使用Simulink软件建立液压电控制动系统的动力学模... 针对某款国产电动汽车的电控液压制动系统,文章基于滑移率的比例-积分-微分(PID)控制提出了防抱死制动系统(ABS)模型,以改善车辆制动性能,提高在对开路面上的制动有效性和安全性。首先,使用Simulink软件建立液压电控制动系统的动力学模型;然后,基于滑移率设计PID控制器,并通过1/4车辆模型验证其有效性;最后,利用S函数将ABS控制器的Simulink模型输入CarSim平台中,开展CarSim/Simulink双平台联合控制仿真。结果表明,基于滑移率的PID控制的ABS对比无ABS的车辆,制动性能更加优越,在对开路面上制动稳定性更加明显。 展开更多
关键词 ABS 电动汽车 电控液压 汽车动力学 CarSim/Simulink联合仿真 制动性能
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SHEL:a semantically enhanced hardware-friendly entity linking method
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作者 亓东林 CHEN Shudong +2 位作者 DU Rong TONG Da YU Yong 《High Technology Letters》 EI CAS 2024年第1期13-22,共10页
With the help of pre-trained language models,the accuracy of the entity linking task has made great strides in recent years.However,most models with excellent performance require fine-tuning on a large amount of train... With the help of pre-trained language models,the accuracy of the entity linking task has made great strides in recent years.However,most models with excellent performance require fine-tuning on a large amount of training data using large pre-trained language models,which is a hardware threshold to accomplish this task.Some researchers have achieved competitive results with less training data through ingenious methods,such as utilizing information provided by the named entity recognition model.This paper presents a novel semantic-enhancement-based entity linking approach,named semantically enhanced hardware-friendly entity linking(SHEL),which is designed to be hardware friendly and efficient while maintaining good performance.Specifically,SHEL's semantic enhancement approach consists of three aspects:(1)semantic compression of entity descriptions using a text summarization model;(2)maximizing the capture of mention contexts using asymmetric heuristics;(3)calculating a fixed size mention representation through pooling operations.These series of semantic enhancement methods effectively improve the model's ability to capture semantic information while taking into account the hardware constraints,and significantly improve the model's convergence speed by more than 50%compared with the strong baseline model proposed in this paper.In terms of performance,SHEL is comparable to the previous method,with superior performance on six well-established datasets,even though SHEL is trained using a smaller pre-trained language model as the encoder. 展开更多
关键词 entity linking(EL) pre-trained models knowledge graph text summarization semantic enhancement
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基于FANUC系统I/O LINK轴的一种新型垂度补偿功能
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作者 张韬 谢丽 李兴迪 《机电工程技术》 2024年第1期95-98,共4页
由于自身重力的原因,配置多附件头的数控落地镗铣床的滑枕在长行程伸出时会在垂直方向上产生相应的形变。为降低由于形变引入的误差对加工精度所造成的影响,以FANUC 0i MF数控系统作为控制平台,结合I/O LINK轴的应用,提出了一种不使用FA... 由于自身重力的原因,配置多附件头的数控落地镗铣床的滑枕在长行程伸出时会在垂直方向上产生相应的形变。为降低由于形变引入的误差对加工精度所造成的影响,以FANUC 0i MF数控系统作为控制平台,结合I/O LINK轴的应用,提出了一种不使用FANUC系统“平直度补偿”功能的补偿方案。运用区间补偿的思想,将整个滑枕的行程划分为多个运动区间,以误差测量实验的方式将滑枕垂向的误差转换为补偿轴的坐标并得出补偿数据,通过PLC程序将补偿轴坐标与滑枕实际位置进行匹配,以同一运动区间调用固定补偿值的方式对滑枕进行线性补偿。通过对不同的附件头创建不同的补偿程序,并使用K地址调用相应补偿数据的方式,排除了不同补偿数据间相互干扰的隐患。所提方案在实际机床中的应用结果表明:其补偿效果可达到与FANUC系统“平直度补偿”功能相一致的水平。 展开更多
关键词 滑枕 I/O link 补偿 PLC程序 区间
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Link Budget and Enhanced Communication Distance for Ambient Internet of Things
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作者 YANG Yibing LIU Ming +2 位作者 XU Rongtao WANG Gongpu GONG Wei 《ZTE Communications》 2024年第1期16-23,共8页
Backscatter communications will play an important role in connecting everything for beyond 5G(B5G)and 6G systems.One open challenge for backscatter communications is that the signals suffer a round-trip path loss so t... Backscatter communications will play an important role in connecting everything for beyond 5G(B5G)and 6G systems.One open challenge for backscatter communications is that the signals suffer a round-trip path loss so that the communication distance is short.In this paper,we first calculate the communication distance upper bounds for both uplink and downlink by measuring the tag sensitivity and reflection coefficient.It is found that the activation voltage of the envelope detection diode of the downlink tag is the main factor limiting the back-scatter communication distance.Based on this analysis,we then propose to implement a low-noise amplifier(LNA)module before the envelope detection at the tag to enhance the incident signal strength.Our experimental results on the hardware platform show that our method can increase the downlink communication range by nearly 20 m. 展开更多
关键词 ambient IoT(AIoT) B5G backscatter communication link budget low-noise amplifier(LNA) Release 19 tag chip sensitivity upper bounds
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IO-Link让阀门更智能
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作者 Dominik Stephan 《流程工业》 2024年第3期20-21,共2页
迄今为止,阀门在工业生产中好像一直都扮演着默默无闻的“安全官”角色,它们控制着各种物质的流入和流出,非常耐心地等待着来自控制系统的指令,维持着生产的稳定运行。现在IO-Link作为一种数字通信接口,可以提供更多的传感器/执行器的数... 迄今为止,阀门在工业生产中好像一直都扮演着默默无闻的“安全官”角色,它们控制着各种物质的流入和流出,非常耐心地等待着来自控制系统的指令,维持着生产的稳定运行。现在IO-Link作为一种数字通信接口,可以提供更多的传感器/执行器的数据,包括过程数据、诊断数据和设备信息等,实现自主调试和双向通信,进一步优化生产线并简化整个工业生产流程。 展开更多
关键词 诊断数据 控制系统 过程数据 link 执行器 双向通信 工业生产 传感器
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倍加福发布全新带IO-Link功能F191RFID超高频读写设备
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《智慧工厂》 2024年第1期27-27,共1页
在生产过程中,为实现产品的跟踪追溯,我们需要对零部件和货物进行无缝识别及跟踪,提升整个生产制造过程的透明度,为工业4.0概念落地奠定基础。如今,倍加福新推新型F191系列RFID读写设备,它结合了先进的工业超高频技术和IO-Link通信标准... 在生产过程中,为实现产品的跟踪追溯,我们需要对零部件和货物进行无缝识别及跟踪,提升整个生产制造过程的透明度,为工业4.0概念落地奠定基础。如今,倍加福新推新型F191系列RFID读写设备,它结合了先进的工业超高频技术和IO-Link通信标准化接口,作为经济高效的使能组件,适用于内部物流、汽车制造、物料搬运等多种应用领域。 展开更多
关键词 link 生产制造过程 读写设备 物料搬运 内部物流 超高频技术 标准化接口 应用领域
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多音干扰下Nakagami-m信道传输Link16数据链的性能分析 被引量:3
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作者 宁晓燕 王影 +1 位作者 孙志国 罗海玲 《系统工程与电子技术》 EI CSCD 北大核心 2023年第2期566-571,共6页
Link16数据链的应用综合广泛,由于运用了跳扩频和编码技术使其具有强大的抗干扰能力。为了探究Link16数据链在衰落信道下的响应,在加性高斯白噪信道的基础之上,研究了Link16数据链经过Nakagami-m衰落信道的系统性能。着重推导了Link16... Link16数据链的应用综合广泛,由于运用了跳扩频和编码技术使其具有强大的抗干扰能力。为了探究Link16数据链在衰落信道下的响应,在加性高斯白噪信道的基础之上,研究了Link16数据链经过Nakagami-m衰落信道的系统性能。着重推导了Link16数据链单脉冲结构在多音干扰下经过Nakagami-m衰落信道的误码率(bit error rate,BER)表达式,并给出了双脉冲结构BER公式。仿真实验结果验证了Link16数据链单脉冲结构在多音干扰下经过Nakagami-m衰落信道的BER公式的准确性,分析了多径参数对Link16数据链抗干扰性能的影响,得出增加衰落参数m和可分辨路径可以提升Link16数据链的系统性能,且当信干比一定、被干扰频点个数在25个及以上时系统BER达到10-1。 展开更多
关键词 link16数据链 NAKAGAMI-M衰落信道 多音干扰 误码率
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低信噪比场景下Link-16系统的联合频偏估计算法 被引量:1
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作者 宁晓燕 罗海玲 +1 位作者 孙志国 刁鸣 《电子与信息学报》 EI CSCD 北大核心 2023年第10期3587-3593,共7页
对于Link-16数据链终端平台在低信噪比(SNR)高动态场景下的多普勒频率偏移问题,该文设计一种新的数据结构,推导了该结构下的克拉默-拉奥下界(CRLB),并在此基础上提出一种联合频域变换与时域自相关运算的分步式频偏估计算法。其基本思想... 对于Link-16数据链终端平台在低信噪比(SNR)高动态场景下的多普勒频率偏移问题,该文设计一种新的数据结构,推导了该结构下的克拉默-拉奥下界(CRLB),并在此基础上提出一种联合频域变换与时域自相关运算的分步式频偏估计算法。其基本思想是,首先对接收信号做自相关处理,然后通过频域变换进行最大值索引,结合修正因子得到多普勒频移的粗估计值,再利用时域的改进L&R算法对接收信号进行细估计,根据两步估计算法得到最终的频偏估计值。算法应用蒙特卡罗实验仿真,仿真结果表明,与传统频偏估计算法相比,该算法的归一化均方误差更接近CRLB,在多普勒频偏为[–20 kHz,20 kHz]时,估计精度可达10^(–5)。在低信噪比环境下,所提算法能达到较为理想的估计效果,适用于Link-16数据链通信。 展开更多
关键词 link-16数据链 克拉默-拉奥下界 自相关处理 改进L&R算法 分步式估计算法
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IO-Link通信从站的设计 被引量:3
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作者 谢倩 胡仁杰 《电气传动》 北大核心 2011年第9期54-57,共4页
为了研究IO-Link系统结构、通信机制以及开发应用,可设计包括IO-Link通用开发模块(或IO-Link通信从站)、分析工具以及从机协议栈在内的IO-Link从机工具包。介绍了IO-Link从机工具包系统,给出了作为从机工具包基础和核心模块的IO-Link从... 为了研究IO-Link系统结构、通信机制以及开发应用,可设计包括IO-Link通用开发模块(或IO-Link通信从站)、分析工具以及从机协议栈在内的IO-Link从机工具包。介绍了IO-Link从机工具包系统,给出了作为从机工具包基础和核心模块的IO-Link从站的设计方案并构建了演示系统,测试结果验证了IO-Link从站软硬件设计的正确性。IO-Link从站的设计对于研究IO-Link系统、通信模式以及从机开发包的后续开发有着重要意义。 展开更多
关键词 IO-link通信 IO-link从机工具包 IO-link从站 IO-link收发器 IO-link从站协议栈
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LINK-A RNAi慢病毒载体构建及其抑制U251胶质瘤细胞增殖的研究
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作者 王军成 兰彦平 +3 位作者 赵岳阳 蒯涛 马东明 李敏 《宁夏医学杂志》 CAS 2023年第7期577-580,F0002,共5页
目的构建lncRNA LINK-A的特异性RNAi慢病毒载体,并借此敲减人U251胶质瘤细胞株内的LINK-A,探究LINK-A对U251胶质瘤细胞增殖的影响。方法针对人LINK-A设计siRNA序列,构建RNAi慢病毒载体质粒并进行测序鉴定;利用pHelper 1.0、pHelper 2.0... 目的构建lncRNA LINK-A的特异性RNAi慢病毒载体,并借此敲减人U251胶质瘤细胞株内的LINK-A,探究LINK-A对U251胶质瘤细胞增殖的影响。方法针对人LINK-A设计siRNA序列,构建RNAi慢病毒载体质粒并进行测序鉴定;利用pHelper 1.0、pHelper 2.0以及shRNAi 3种质粒分别转染293T细胞,筛选分离慢病毒并测定滴度;用PBS及构建好的慢病毒感染人U251胶质瘤细胞,实验分3组:空白组(PBS)、NC组(空载病毒)、LINK-A(-)组(LINK-A RNAi慢病毒),72 h后利用RT-PCR检测细胞中LINK-A的表达情况;取病毒感染成功后的U251胶质瘤细胞行平板克隆实验培养10 d,行CCK-8实验分别于24 h、48 h检测。结果RNAi慢病毒载体质粒测序结果与RNAi设计序列一致,提示LINK-A RNAi慢病毒载体构建成功,滴度为3×108 TU/mL;病毒感染U251胶质瘤细胞72h后,细胞生长状态良好,荧光持续稳定表达,LINK-A RNA相对表达量明显降低(P<0.05),表明病毒成功感染U251细胞;10 d后LINK-A(-)组细胞克隆形成数及形成率较空白组及NC组明显减少(P<0.05);与空白组及NC组相比,24 h后LINK-A(-)组OD值减少(P<0.05),72 h明显减少(P<0.05)。结论人LINK-A RNAi慢病毒构建成功;LINK-A表达降低可抑制U251胶质瘤细胞增殖。 展开更多
关键词 胶质瘤 增殖 link-A RNAI
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Self-Cross-Linked Tannin-Aminated Tannin Surface Coatings for Particleboard
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作者 Bengang Zhang Antonio Pizzi +2 位作者 Mathieu Petrissans Anelie Petrissans Colin Baptiste 《Journal of Renewable Materials》 EI 2023年第12期4097-4121,共25页
Aminated tannins were prepared by reacting mimosa condensed tannin extract with ammonia yielding the substitution of many,if not all of the tannin hydroxyl groups with–NH_(2)groups.A tannin-aminated tannin(ATT)partic... Aminated tannins were prepared by reacting mimosa condensed tannin extract with ammonia yielding the substitution of many,if not all of the tannin hydroxyl groups with–NH_(2)groups.A tannin-aminated tannin(ATT)particleboard coating was then prepared by reacting raw tannin extract with aminated tannin extract and thus cross-linking the two by substituting tannin’s hydroxyl groups with the–NH_(2)groups on the aminated tannin to form–NH-bridges between the two.The resulting particleboard coating gave encouraging results when pressed at 180℃for 3 min.Conversely,the system in which tannin was reacted/cross-liked with urea(ATU)by a similar amination reaction did not perform as well as the ATT system,and this even when a higher curing temperature and longer hot press time were used.In particular its water repellence was worse probably due to the presence of urea and such a system with lower reactivity.Nonetheless,substituting the tannin–OHs with the urea–NH_(2)groups appeared to also take place.ATT gave better results than ATU as regards water repellence and mechanical resistance as shown by the cross cut test.The ATT system was shown to be between 95%and 98%biosourced.The difference appeared to be due,by TMA analysis,to the much faster formation of the ATT hardened network leading to a better cross-linked polymer coating.The chemical species formed for both the ATT and ATU system were studied by MALDI ToF and CP MAS^(13)C NMR. 展开更多
关键词 Biocoatings PARTICLEBOARD aminated tannin cross-linked tannin-aminated tannin tannin-urea cross links water repellence cross cut test MALDI ToF ^(13)C NMR
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