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NaNbO_(3)基无铅储能介质陶瓷研究进展

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硅酸盐学报 2024年第4期52卷 1460-1476页

作者：王震涛李达赵维琛刘津男徐谛明周迪西安交通大学电信学部电子科学与工程学院西安710049

高性能环境友好型NaNbO_(3)(NN)基储能介质陶瓷由于其功率密度高、放电时间短,在脉冲功率电子器件方面具有广泛的应用。优异的储能性能及其温度稳定性、抗疲劳特性及工艺重复性等综合性能是NN基无铅陶瓷被广泛应用的前提。本文主要综述... 详细信息

高性能环境友好型NaNbO_(3)(NN)基储能介质陶瓷由于其功率密度高、放电时间短,在脉冲功率电子器件方面具有广泛的应用。优异的储能性能及其温度稳定性、抗疲劳特性及工艺重复性等综合性能是NN基无铅陶瓷被广泛应用的前提。本文主要综述近几年来国内外有关NN基储能陶瓷的相结构调控、微观形貌优化、掺杂改性(A位、B位及A/B位共掺)以及相关机理研究方面的进展和动向。最后,对NN基无铅储能陶瓷在原料制备、烧结工艺、成型工艺、理论研究和器件研制方面的未来发展进行展望。

关键词：无铅反铁电陶瓷铌酸钠掺杂改性电介质储能

Parameter estimation of GTD model and RCS extrapolation based on a modified 3D-ESPRIT algorithm

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Journal of Systems Engineering and Electronics 2020年第6期31卷 1206-1215页

作者： ZHENG Shuyu ZHANG Xiaokuan zhao weichen ZHOU Jianxiong ZONG Binfeng XU Jiahua Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China College of Economics Jilin University of Finance and EconomicsChangchun 130022China School of Electronics Science and Engineering National University of Defense TechnologyChangsha 410073China

The noise robustness and parameter estimation performance of the classical three-dimensional estimating signal parameter via rotational invariance techniques(3D-ESPRIT)algorithm are poor when the parameters of the geometric theory of the diffraction(GTD)model are estimated at low signal-to-noise ratio(SNR).To solve this problem,a modified 3D-ESPRIT algorithm is *** modified algorithm improves the parameter estimation accuracy by proposing a novel spatial smoothing ***,we make cross-correlation of the auto-correlation matrices;then by averaging the cross-correlation matrices of the forward and backward spatial smoothing,we can obtain a novel equivalent spatial smoothing *** formula of the modified algorithm is derived and the performance of this improved method is also *** we compare root-meansquare-errors(RMSEs)of different parameters and the locating accuracy obtained by different ***,radar cross section(RCS)of radar targets is *** results verify the effectiveness and superiority of the modified 3DESPRIT algorithm.

关键词： parameter estimation novel spatial smoothing scattering center geometric theory of diffraction(GTD)model radar cross section(RCS)extrapolation

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基于模型的涡扇发动机性能衰减评估

机械制造与自动化 2024年第2期53卷 224-228页

作者：赵伟辰王晨李兆红杨怀丰王军中国航发沈阳发动机研究所辽宁沈阳110066

为了获得涡扇发动机寿命期内各部件性能衰减程度与衰减趋势,基于发动机性能计算模型与部件特性衰减因子,采用序列二次优化算法对1台300 h持久试车的发动机各阶段部件性能衰减情况进行寻优计算。计算结果表明:模型计算结果与试验测量结... 详细信息

为了获得涡扇发动机寿命期内各部件性能衰减程度与衰减趋势,基于发动机性能计算模型与部件特性衰减因子,采用序列二次优化算法对1台300 h持久试车的发动机各阶段部件性能衰减情况进行寻优计算。计算结果表明:模型计算结果与试验测量结果误差最大为4.33%,绝大部分参数误差在±2.0%范围;高压部件持久试车前期衰减,后期低压部件衰减较快,300 h试车后压气机与低压涡轮衰减最严重。

关键词：涡扇发动机性能衰减衰减因子序列二次优化算法持久试车

China's policy framework for carbon capture,utilization and storage:Review,analysis,and outlook

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Frontiers in Energy 2023年第3期17卷 400-411页

作者： Qiao MA Shan WANG Yan FU Wenlong ZHOU Mingwei SHI Xueting PENG Haodong LV weichen zhao Xian ZHANG National Engineering Laboratory for Reducing Emissions from Coal Combustion Engineering Research Center of Environmental Thermal Technology of the Ministry of EducationShandong Key Laboratory of Energy Carbon Reduction and Resource UtilizationSchool of Energy and Power EngineeringShandong UniversityJinan 250061China The Administrative Center for China's Agenda 21 Beijing 100038China Center for Sustainable Development and Energy Policy Research School of Energy and Mining EngineeringChina University of Mining and Technology(Beijing)Beijing 100083China The Bartlett School of Sustainable Construction University College LondonLondon WC1E 7HBUK

Carbon capture,utilization,and storage(CCUS)is estimated to contribute substantial CO_(2)emission reduction to carbon neutrality in *** is yet a large gap between such enormous demand and the current capacity,and thus a sound enabling environment with sufficient policy support is imperative for CCUS *** study reviewed 59 CCUS-related policy documents issued by the Chinese government as of July 2022,and found that a supporting policy framework for CCUS is taking embryonic form in *** than ten departments of the central government have involved CCUS in their policies,of which the State Council,the National Development and Reform Commission(NDRC),the Ministry of Science and Technology(MOST),and the Ministry of Ecological Environment(MEE)have given the greatest attention with different *** policy terms are further analyzed following the method of content analysis and categorized into supply-,environment-and demand-type *** results indicate that supply-type policies are unbalanced in policy objectives,as policy terms on technology research and demonstration greatly outnumber those on other objectives,and the attention to weak links and industrial sectors is far from ***-type policies,especially legislations,standards,and incentives,are inadequate in pertinence and ***-type policies are absent in the current policy system but is essential to drive the demand for the CCUS technology in domestic and foreign *** meet the reduction demand of China's carbon neutral goal,policies need to be tailored according to needs of each specific technology and implemented in an orderly manner with well-balanced use on multiple objectives.

关键词： carbon capture utilization and storage(CCUS) policy content analysis China

头孢他啶/阿维巴坦在重症革兰氏阴性菌感染临床治疗中的研究进展

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世界临床药物 2024年第3期45卷 327-332页

作者：赵宗彪赵为陈何春远蒋俊杰沈炳香王法财安徽医科大学附属六安医院(六安市人民医院)药学部安徽六安237005

头孢他啶(ceftazidime)/阿维巴坦(avibactam)是第3代头孢他啶与新型非β-内酰胺酶抑制剂组合的复合制剂。目前已获批用于治疗医院获得性肺炎(pneumonia)、呼吸机相关性肺炎及复杂性腹腔感染等治疗药物有限的重症感染,且逐步在复杂性尿... 详细信息

头孢他啶(ceftazidime)/阿维巴坦(avibactam)是第3代头孢他啶与新型非β-内酰胺酶抑制剂组合的复合制剂。目前已获批用于治疗医院获得性肺炎(pneumonia)、呼吸机相关性肺炎及复杂性腹腔感染等治疗药物有限的重症感染,且逐步在复杂性尿路感染、颅内感染的临床治疗中开展应用,并表现出明显优势。该文主要从头孢他啶/阿维巴坦的药理作用、药代动力学、临床应用及用药方法等方面作综述,以期为临床用药提供一定参考,促进合理用药。

关键词：头孢他啶/阿维巴坦革兰氏阴性菌感染临床治疗

Translocation and transformation of engineered nanomaterials in plant cells and their effect on metabolism

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BIOCELL 2023年第3期47卷 493-502页

作者： weichen zhao PINGFAN ZHOU BENZHEN LOU YAQI JIANG YUANBO LI MINGSHU LI NOMAN SHAKOOR YUKUI RUI Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation College of Resources and Environmental SciencesChina Agricultural UniversityBeijing100193China China Agricultural University Professor Workstation of Yuhuangmiao Town Jinan251600China China Agricultural University Professor Workstation of Sunji Town Jinan251600China Jiaer Chen Academician Workstation Jinan251600China

As the climate worsens and the demand for food grows,so does the interest in *** interaction between plants and nanomaterials(NMs)has been extensively and intensively ***,stopping at the outcome of a phenomenon is often ***,we introduce three important processes of nanoparticleplant interactions:translocation,transformation,and plant *** the migration of nanoparticles,size and surface electrical properties are the main determining ***,the interaction of nanoparticles with cell membranes is another key aspect of *** transformation of nanoparticles in plants is mainly due to redox *** way that nanoparticles affect plant metabolism may be able to shed light on the interaction of nanoparticles with *** review adds to the existing knowledge on the design of nanoagrochemicals and summarizes the mechanism of interaction of NMs with *** this way,NMs can be used for their beneficial effects and thus contribute to the maintenance of food security and sustainable development.

关键词： Interaction Nanoagriculture Nanoparticles Internalization

Human lineage mutations regulate RNA-protein binding of conserved genes NTRK2 and ITPR1 involved in human evolution

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General Psychiatry 2024年第3期37卷 375-387页

作者： Wenxiang Cai weichen Song Shunying Yu Min zhao Guan Ning Lin Shanghai Mental Health Center Shanghai Jiao Tong University School of MedicineSchool of Biomedical EngineeringShanghai Jiao Tong UniversityShanghaiChina Shanghai Key Laboratory of Psychotic Disorders ShanghaiChina

Background The role of human lineage mutations(HLMs)in human evolution through post-transcriptional modification is *** To investigate the contribution of HLMs to human evolution through post-transcriptional *** We applied a deep learning model Seqweaver to predict how HLMs impact RNA-binding protein *** We found that only 0.27%of HLMs had significant impacts on RNA-binding proteins at the threshold of the top 1%of human common *** HLMs enriched in a set of conserved genes highly expressed in adult excitatory neurons and prenatal Purkinje neurons,and were involved in synapse organisation and the GTPase *** genes also carried excess damaging coding mutations that caused neurodevelopmental disorders,ataxia and *** these genes,NTRK2 and ITPR1 had the most aggregated evidence of functional importance,suggesting their essential roles in cognition and *** Our findings suggest that a small subset of human-specific mutations have contributed to human speciation through impacts on post-transcriptional modification of critical brain-related genes.

关键词： evolution conserved Human

Cryogenian and Ediacaran integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 919-949页

作者： Lang SUN Malik Muhammad Saud Sajid KHAN Chuan YANG Zhixin SUN Bing PAN Shehryar AHMED Lanyun MIAO weichen SUN Chunlin HU Xiaojuan SUN Cui LUO Bo CHEN Zongjun YIN Fangchen zhao Guoxiang LI Maoyan ZHU State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The complex evolutionary history of the Qinghai-Tibetan Plateau and its surrounding areas,including the continental blocks(Indian,Lhasa,South Qiangtang,Tarim,Olongbuluk,Central Qilian,Alxa,North China,Yangtze,Central Iran and Oman)and the orogenic belts between them,has long been the frontier in Earth science *** Cryogenian and Ediacaran strata are extensively distributed in these ***,relatively complete Cryogenian and Ediacaran successions have been discovered in Oman,Indian,Yangtze,and Tarim blocks,while only the Ediacaran successions have been reported in Iran,the South Qiangtang,Central Qilian,Alxa,and North China *** on previous studies together with the integration of new materials and advancement obtained through the Second Tibetan Plateau Scientific Expedition and Research,this review aims to synthesize a correlative stratigraphic framework of the representative Cryogenian and Ediacaran sequences from the Qinghai-Tibetan Plateau and its surrounding ***,the Cryogenian and Ediacaran biotas and major geological events in these areas are comprehensively discussed in aspects of current research *** results indicate that,in general,Ediacaran fossils of each area exhibit distinct features in preservation and assemblage composition,but the typical late Ediacaran fossils Cloudina and Shaanxilithes have been reported from most of these *** addition to the two global Cryogenian glaciations,late Ediacaran glaciogenic deposits are extensively recorded in the areas within and around the northern QinghaiTibetan Plateau(including the North China,Alxa,Central Qilian,Olongbuluk,and Tarim blocks,and the North Qilian Accretionary Belt),as well as central and southern ***,further research is required to determine the age,distribution,and origin of these late Ediacaran glaciogenic ***,the middle Ediacaran DOUNCE/Shuram Excursion is widely documented in the Qinghai-Tibetan Plateau and its surroundi

关键词： Qinghai-Tibetan Plateau Cryogenian Ediacaran Stratigraphy Palaeogeography Biota Gondwana

基于改进2D-ESPRIT算法的二维GTD模型参数估计

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华南理工大学学报（自然科学版） 2020年第5期48卷 75-81,91页

作者：张小宽郑舒予赵唯辰宗彬锋李江空军工程大学防空反导学院陕西西安710051 空军工程大学研究生院陕西西安710051 吉林财经大学吉林长春130022

针对经典2D-ESPRIT算法在估计基于几何绕射理论的二维GTD模型参数时受噪声影响较大这一问题,提出了一种改进的2D-ESPRIT算法,有效提高了算法的抗噪性能与参数估计性能。改进算法在经典2D-ESPRIT算法的基础上,首先通过构建交换矩阵,得到... 详细信息

针对经典2D-ESPRIT算法在估计基于几何绕射理论的二维GTD模型参数时受噪声影响较大这一问题,提出了一种改进的2D-ESPRIT算法,有效提高了算法的抗噪性能与参数估计性能。改进算法在经典2D-ESPRIT算法的基础上,首先通过构建交换矩阵,得到含有原始数据Ee共轭信息的另一矩阵Y;其次在通过自相关与互相关处理、叠加取平均,得到新的协方差矩阵R;最后对协方差矩阵解算,估计得到二维GTD模型各参数值。仿真实验表明,改进2D-ESPRIT算法抗噪性能要优于经典2D-ESPRIT算法,在信噪比较低的情况下,改进2D-ESPRIT算法估计得到的模型参数精度更高,性能更稳定。文中还针对其他因素(如矩阵束参数及配对标量β值)对模型参数估计精度的影响进行了探究,为后续仿真实验提供了参考。

关键词：参数估计散射中心二维GTD模型改进2D-ESPRIT算法共轭矩阵