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Perfect reconstruction image modulation based on BEMD and quaternionic analytic signals

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Science china(Information sciences) 2011年第12期54卷 2622-2634页

作者： QIAO liHong 1 , NIU KaiFu 2 , wang ning 2 & peng lizhong 2 1 College of Information Science and Engineering, Henan university of Technology, Zhengzhou 450001, china 2 school of mathematical sciences, peking university, beijing 100871, china College of Information Science and Engineering Henan University of Technology Zhengzhou China school of mathematical sciences Peking University Beijing China

Image modulation represents image by meaningful characters such as image instantaneous amplitude and instantaneous frequency. A perfect reconstruction image modulation method is proposed. In detail, the bidimensional empirical mode decomposition (BEMD) is first improved to adaptively decompose image into monocomponents. Then by the quaternionic analytic method, suitable analytic signals is acquired. A new polar form is further proposed to modulate images, then seven characters are derived including instantaneous amplitude and instantaneous frequencies. We demonstrate the techniques on both synthetic and natural images, depict the needle program of the estimated frequencies and obtain the reconstructions that are the same with the original images. The applications in image segmentation and separation establish the validity of characterizing images of this type as sums of locally narrow band modulated components.

关键词： perfect reconstruction image modulation AM-FM representation BEMD quaternionic analytic signals

Concise Synthesis of Lactococcus garvieae lipoteichoic Acids Through an Additive-Modulated Preactivation Protocol and the Immunological Studies

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CCS Chemistry 2024年第2期6卷 403-414页

作者： Tianlu li Tong li Yue Yang Haoru Zhuang Jianwu Lv ning Zhou Miaomiao Zhang Fengshan wang Yiqun Geng Richard R.Schmidt peng peng National Glycoengineering Research Center Shandong Key Laboratory of Carbohydrate Chemistry and GlycobiologyNMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate Based MedicineShandong UniversityQingdao 266237 State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050 Department of Chemistry University of KonstanzD-78457 Konstanz

lipoteichoic acids(LTAs)are macroamphiphiles composed of alditol,lipid,phosphate,and carbohydrate *** to their inherent complexity,it is a severe challenge to access LTAs with structural integrity from natural sources for biological or immunological ***,we describe the first total synthesis of Lactococcus garvieae LTA(type II LTA),containing five distinct 1,2-cis gluco/galactopyranosidic linkages,via a novel additive-modulated O-glycosyl trichloroacetimidate preactivation glycosidation *** strategy features(1)high glycosidation yields and excellent 1,2-cis stereoselectivities independent of the donor anomeric configuration,(2)common and inexpensive reagents as promoters and additives,(3)application to standard glycosyl imidate donors without resorting to participating protection,and(4)general application to reactive and less reactive glycosyl ***,via the precise stereocontrolled construction of three galactopyranosidic and two glucopyranosidic bonds on a multigram scale,a series of structurally well-defined LTA molecules were successfully *** evaluation of these type II synthetic LTAs showed a structure–activity relationship in the stimulation of a proinflammatory response.

关键词： 1,2-cis glycosidation stereoselectivity lipoteichoic acid total synthesis additive-modulated trichloroacetimidate glycosidation immune response

A post-modification strategy to precisely construct dual-atom sites for oxygen reduction electrocatalysis

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Journal of Energy Chemistry 2024年第3期90卷 511-517,I0012页

作者： Juan wang Xinyan liu Chang-Xin Zhao Yun-Wei Song Jia-ning liu Xi-Yao li Chen-Xi Bi Xin Wan Jianglan Shui Hong-Jie peng Bo-Quan li Jia-Qi Huang school of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Institute of Fundamental and Frontier sciences University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina school of Materials Science and Engineering Beihang UniversityBeijing 100191China

Dual-atom catalysts(DACs) afford promising potential for oxygen reduction electrocatalysis due to their high atomic efficiency and high intrinsic ***,precise construction of dual-atom sites remains a *** this work,a post-modification strategy is proposed to precisely fabricate DACs for oxygen reduction ***,a secondary metal precursor is introduced to the primary single-atom sites to introduce direct metal-metal interaction,which ensures the formation of desired atom pair structure during the subsequent pyrolysis process and allows for successful construction of *** as-prepared FeCo-NC DAC exhibits superior oxygen reduction electrocatalytic activity with a half-wave potential of 0,91 V *** hydrogen ***-air batteries equipped with the FeCo-NC DAC demonstrate higher peak power density than those with the Pt/C *** importantly,this post-modification strategy is demonstrated universal to achieve a variety of dual-atom *** work presents an effective synthesis methodology for precise construction of catalytic materials and propels their applications in energy-related devices.

关键词： Dual-atom catalysts Electrocatalysis Oxygen reduction reaction Post-modification Zinc–air batteries

Effect of slow shot speed on externally solidified crystal,porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy

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china Foundry 2024年第1期21卷 11-19页

作者： Wen-ning liu Wei Zhang peng-yue wang Yi-xian liu Xiang-yi Jiao Ao-xiang Wan Cheng-gang wang Guo-dong Tong Shou-mei Xiong school of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Tsinghua UniversityBeijing 100084Beijing china FAW Group Co. Ltd.Changchun 130013China china FAW Foundry Co. Ltd.Changchun 130013China

The effect of slow shot speed on externally solidified crystal(ESC),porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy was investigated by optical microscopy(OM),scanning electron microscopy(SEM)and laboratory computed tomography(CT).Results showed that the newly developed AlSi9MnMoV alloy exhibited improved mechanical properties when compared to the AlSi10MnMg *** AlSi9MnMoV alloy,which was designed with trace multicomponent additions,displays a notable grain refining effect in comparison to the AlSi10MnMg *** elements Ti,Zr,V,Nb,B promote heterogeneous nucleation and reduce the grain size of primaryα-*** a lower slow shot speed,the large ESCs are easier to form and gather,developing into the dendrite net and *** an increase in slow shot speed,the size and number of ESCs and porosities significantly *** addition,the distribution of ESCs is more dispersed and the net-shrinkage *** tensile property is greatly improved by adopting a higher slow shot *** ultimate tensile strength is enhanced from 260.31 MPa to 290.31 MPa(increased by 11.52%),and the elongation is enhanced from 3.72%to 6.34%(increased by 70.52%).

关键词： hypoeutectic Al-Si alloy high pressure die casting porosity externally solidified crystal tensile property

IbNIEL-mediated degradation of IbNAC087 regulates jasmonic acid-dependent salt and drought tolerance in sweet potato

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Journal of Integrative Plant Biology 2024年第2期66卷 176-195页

作者： Xu li Zhen wang Sifan Sun Zhuoru Dai Jun Zhang Wenbin wang Kui peng Wenhao Geng Shuanghong Xia Qingchang liu Hong Zhai Shaopei Gao ning Zhao Feng Tian Huan Zhang Shaozhen He Key Laboratory of Sweet Potato Biology and Biotechnology Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis&Utilization and Joint Laboratory for International Cooperation in Crop Molecular BreedingMinistry of EducationCollege of Agronomy&BiotechnologyChina Agricultural UniversityBeijing 100193China Sanya Institute of china Agricultural university Sanya 572025China State Key Laboratory of Plant Physiology and Biochemistry National Maize Improvement CenterKey Laboratory of Biology and Genetic Improvement of MaizeBeijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijing 100193China

Sweet potato(Ipomoea batatas[L.]Lam.)is a crucial staple and bioenergy *** abiotic stress tolerance holds significant importance in fully utilizing marginal *** processes regulate abiotic stress responses,yet the molecular regulatory mechanisms in sweet potato remain *** this study,a NAC(NAM,ATAF1/2,and CUC2)transcription factor,IbNAC087,was identified,which is commonly upregulated in salt-and drought-tolerant *** of IbNAC087 increased salt and drought tolerance by increasing jasmonic acid(JA)accumulation and activating reactive oxygen species(ROS)scavenging,whereas silencing this gene resulted in opposite ***-rich IbNAC087-OE(overexpression)plants exhibited more stomatal closure than wild-type(WT)and IbNAC087-Ri plants under NaCl,polyethylene glycol,and methyl jasmonate ***087 functions as a nuclear transcriptional activator and directly activates the expression of the key JA biosynthesisrelated genes lipoxygenase(IbLOX)and allene oxide synthase(IbAOS).Moreover,IbNAC087 physically interacted with a RING-type E3 ubiquitin ligase NAC087-INTERACTING E3 liGASE(IbNIEL),negatively regulating salt and drought tolerance in sweet *** ubiquitinated IbNAC087 to promote 26S proteasome degradation,which weakened its activation on IbLOX and *** findings provide insights into the mechanism underlying the IbNIEL-IbNAC087 module regulation of JA-dependent salt and drought response in sweet potato and provide candidate genes for improving abiotic stress tolerance in crops.

关键词： abiotic tolerance IbNAC087 IbNIEL JA sweet potato

Recent progress of radionuclides separation by porous materials

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Science china Chemistry 2024年第11期67卷 3515-3577页

作者： Yinghui Xie Long Yu Long Chen Cheng Chen li wang Fenglei liu Yun liao peng Zhang Tao Chen Yihui Yuan Yuexiang Lu Boyang Huang Hui Yang Suhua wang Shuao wang lijian Ma Feng Luo Yunhai liu Baowei Hu Hongqing wang Duoqiang Pan Wenkun Zhu ning wang Zhe wang liang Mao Shengqian Ma Xiangke wang Guangdong Provincial Key Laboratory for Green Agricultural Production and Intelligent Equipment School of Environmental Science and Engineering Guangdong University of Petrochemical Technology school of life Science Shaoxing University College of Environmental Science and Engineering North China Electric Power University State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions Soochow University College of Chemistry Sichuan University school of Chemistry and Materials Science East China University of Technology school of Chemistry and Chemical Engineering University of South China Frontiers Science Center for Rare Isotopes Lanzhou University State Key Laboratory of Environment-friendly Energy Materials National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety Sichuan Civil-military Integration Institute School of National Defence & Nuclear Science and TechnologySouthwest University of Science and Technology State Key Laboratory of Marine Resource Utilization in South china Sea Collaborative Innovation Center of Marine Science and Technology Hainan University Institute of Nuclear and New Energy Technology Tsinghua University State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Department of Chemistry University of North Texas

The separation of radionuclides is critical for the sustainable development of nuclear energy. It is urgent to design and prepare functionalized materials for efficient radionuclides separation. Porous materials are considered excellent candidates for the separation of radionuclides under complex conditions due to their high specific surface areas, tunable pore structures and controllable functionalities. In this review, we summarized the design, preparation and functionalization of porous materials and their application for separation of radionuclides in the past five years, discussed the separation performance and analyzed the structure-activity relationship between various radionuclides and porous materials, and systematically clarified their characterization and mechanism of different type porous materials. We also introduced the detection, irradiation and chemical toxicity of different reflective radionuclides.

关键词： porous materials radionuclides detection separation radiotoxicity interaction mechanism

Balloon Angioplasty for Symptomatic Intracranial Artery Stenosis (BASIS): protocol of a prospective, multicentre, randomised, controlled trial

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Stroke & Vascular Neurology 2024年第1期9卷 66-74页

作者： Xuan Sun Ming Yang Dapeng Sun Guangge peng Yiming Deng Xingquan Zhao liping liu ning Ma Feng Gao Dapeng Mo Wengui Yu Yongjun wang Yilong wang Zhongrong Miao Department of Interventional Neuroradiology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Neurology Beijing Luhe HospitalCapital Medical UniversityBeijingChina Department of Neurology Comprehensive Stroke&Cerebrovascular CenterUniversity of California IrvineIrvineCaliforniaUSA Chinese Institute for Brain Research BeijingChina National Center for Neurological Diseases BeijingChina Advanced Innovation Center for Human Brain Protection Capital Medical UniversityBeijingChina china National Clinical Research Center for Neurological Diseases BeijingChina beijing Laboratory of Oral Health Capital Medical UniversityBeijingChina

Background The superiority of balloon angioplasty plus aggressive medical management(AMM)to AMM alone for symptomatic intracranial artery stenosis(sICAS)on efficacy and safety profiles still lacks evidence from randomised controlled trials(RCTs).Aim To demonstrate the design of an RCT on balloon angioplasty plus AMM for *** Balloon Angioplasty for Symptomatic Intracranial Artery Stenosis(BASIS)trial is a multicentre,prospective,randomised,open-label,blinded end-point trial to investigate whether balloon angioplasty plus AMM could improve clinical outcome compared with AMM alone in patients with *** eligible in BASIS were 35–80 years old,with a recent transient ischaemic attack within the past 90 days or ischaemic stroke between 14 days and 90 days prior to enrolment due to severe atherosclerotic stenosis(70%–99%)of a major intracranial *** eligible patients were randomly assigned to receive balloon angioplasty plus AMM or AMM alone at a 1:1 *** groups will receive identical AMM,including standard dual antiplatelet therapy for 90 days followed by long-term single antiplatelet therapy,intensive risk factor management and life-style *** participants will be followed up for *** outcomes Stroke or death in the next 30 days after enrolment or after balloon angioplasty procedure of the qualifying lesion during follow-up,or any ischaemic stroke or revascularisation from the qualifying artery after 30 days but before 12 months of enrolment,is the primary *** BASIS trail is the first RCT to compare the efficacy and safety of balloon angioplasty plus AMM to AMM alone in sICAS patients,which may provide an alternative perspective for treating *** registration number NCT03703635;https://***.

关键词： balloon prospective centre

First-principle study of interaction of H2 and H2O molecules with （ZnO）_n（n=3-6） ring clusters

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Progress in Natural Science:Materials International 2010年第1期20卷 30-37页

作者： Hua-peng CHEN~1,Jian-ning DING~(2,3),ning-yi YUAN~2,Xiu-qin wang~2,Cheng-lung CHEN~4,Duan WENG~(1*) 1.Department of Materials Science and Engineering,Tsinghua Universtiy,beijing 100084,china 2.Center for Low-dimensional Materials,Micro-nano Devices and System, Jiangsu Polytechnic university,Changzhou 213164,china 3.Key Laboratory of New Energy Source,Changzhou 213164,china 4.Department of Chemistry,National Sun Yat-sen university,Kaohsiung 80424,Taiwan,china Department of Materials Science and Engineering Tsinghua Universtiy Beijing 100084 China Center for Low-dimensional Materials Micro-nano Devices and System Jiangsu Polytechnic University Changzhou 213164 China Key Laboratory of New Energy Source Changzhou 213164 China Department of Chemistry National Sun Yat-sen University Kaohsiung 80424 Taiwan China

A density functional calculation was performed to investigate the impact of hydrogen and water molecules on zinc oxide clusters（ZnO）n=3-6…X,where X=H2and *** calculated binding energies were corrected for the basis set superposition error （BSSE）.The structural parameters and chemical hardness were calculated for the complexes of zinc oxide clusters and guest *** strength values of the interaction between the clusters and the guest molecules were analyzed based on the topological properties of atoms in molecules（AIM）theory of *** stereo electronic interactions inside the ZnO clusters were analyzed in detail using the natural bond orbital（NBO）analysis.

关键词： density functional theory zinc oxide clusters atoms in molecules

10B-doped MCP detector developed for neutron resonance imaging at Back-n white neutron source

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Nuclear Science and Techniques 2024年第8期35卷 58-68页

作者： Qiang li li‑Jiao wang Jing‑Yu Tang Xiang‑Biao Qiu Zhen Chen Mao‑Yuan Zhao Chang‑Jun ning Kai Pan Wei Xu Tao li Su‑peng Lu Han Yi Rui‑Rui Fan Chang‑Qing Feng Rong Zhang Xiao‑Yang Sun Qi An Hao‑Fan Bai Jiang‑Bo Bai Jie Bao Ping Cao Qi‑Ping Chen Yong‑Hao Chen Zeng‑Qi Cui An‑Chuan Fan Fan‑Zhen Feng Min‑Hao Gu Chang‑Cai Han Zi‑Jie Han Guo‑Zhu He Yong‑Cheng He Yang Hong Yi‑Wei Hu Han‑Xiong Huang Wei Jiang Zhi‑Jie Jiang Zheng‑Yao Jin ling Kang Bo li Gong li Xiao li Yang li Jie liu Rong liu Shu‑Bin liu Yi‑Na liu Guang‑Yuan Luan Jie Ren Zhi‑Zhou Ren Xi‑Chao Ruan Zhao‑Hui Song Kang Sun Zhi‑Xin Tan Sheng‑Da Tang Jin‑Cheng wang peng‑Cheng wang Zhao‑Hui wang Zhong‑Wei Wen Xiao‑Guang Wu Xuan Wu Cong Xia Yong‑Ji Yu Guo‑Hui Zhang Hang‑Chang Zhang lin‑Hao Zhang Qi‑Wei Zhang Xian‑peng Zhang Yu‑liang Zhang Yue Zhang Zhi‑Yong Zhang Zhi‑Hao Zhou Ke‑Jun Zhu Chong Zou Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China State Key Laboratory of Particle Detection and Electronics Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Dongguan Songshan Lake Future school Dongguan 523808China school of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China North Night Vision Science and Technology(Nanjing)Research Institute Co.Ltd Nanjing 211106China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Institute of Modern Physics Fudan UniversityShanghai 200433China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China china Academy of Engineering Physics Institute of Nuclear Physics and ChemistryMianyang 621900China USTC archaeometry lab University of Science and Technology of ChinaHefei 230026China Northwest Institute of Nuclear Technology Xi’an 710024China university of Chinese Academy of sciences Beijing 100049China china Shipbuilding Trading Co. LtdBeijing 100044China

Neutron resonance imaging(NRI)has recently emerged as an appealing technique for neutron *** complexity surpasses that of conventional transmission imaging,as it requires a high demand for both a neutron source and ***,the progression of NRI technology has been sluggish since its inception in the 1980s,particularly considering the limited studies analyzing the neutron energy range above *** white neutron source(Back-n)at the china Spallation Neutron Source(CSNS)provides favorable beam conditions for the development of the NRI technique over a wide neutron energy range from eV to ***-sensitive microchannel plates(MCP)have emerged as a cutting-edge tool in the field of neutron detection owing to their high temporal and spatial resolutions,high detection efficiency,and low *** this study,we report the development of a 10B-doped MCP detector,along with its associated electronics,data processing system,and NRI experiments at the *** heavy elements such as gold,silver,tungsten,and indium can be easily identified in the transmission images by their characteristic resonance peaks in the 1–100 eV energy range;the more difficult medium-weight elements such as iron,copper,and aluminum with resonance peaks in the 1–100 keV energy range can also be *** particular,results in the neutron energy range of dozens of keV(Aluminum)are reported here for the first time.

关键词： Neutron resonance imaging 10B doped MCP detector White neutron source Sample nuclide identification