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Microwave heating as a universal method to transform confined molecules into armchair graphene nanoribbons

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Nano Research 2023年第7期16卷 10644-10651页

作者： Haoyuan zhang Yingzhi Chen Kunpeng Tang Ziheng Lin Xuan Li hongwei zhang Yifan zhang Chi Ho Wong Chi Wah Leung Chee Leung Mak Yuan Hu Weili Cui Kecheng Cao Lei Shi State Key Laboratory of Optoelectronic Materials and Technologies Nanotechnology Research CenterGuangdong Province Key Lab of Display Material and TechnologySchool of Materials Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China Huzhou Key Laboratory of Environmental Functional Materials and Pollution Control School of EngineeringHuzhou UniversityHuzhou 313000China Department of Industrial and Systems Engineering Research Institute for Advanced ManufacturingThe Hong Kong Polytechnic UniversityHong Kong 999077China Department of Applied Physics The Hong Kong Polytechnic UniversityHong Kong 999077China Shanghai Key Laboratory of High-resolution Electron Microscopy ShanghaiTech UniversityShanghai 201210China

Armchair graphene nanoribbons(AGNRs)with sub-nanometer width are potential materials for the fabrication of novel nanodevices thanks to their moderate direct band *** are usually synthesized by polymerizing precursor molecules on substrate ***,it is time-consuming and not suitable for large-scale *** can also be grown by transforming precursor molecules inside single-walled carbon nanotubes(SWCNTs)via furnace annealing,but the obtained AGNRs are normally *** this work,microwave heating is applied for transforming precursor molecules into *** fast heating process allows synthesizing the AGNRs in *** different molecules were successfully transformed into AGNRs,suggesting that it is a universal *** importantly,as demonstrated by Raman spectroscopy,aberrationcorrected high-resolution transmission electron microscopy and theoretical calculations,less twisted AGNRs are synthesized by the microwave heating than the furnace *** results reveal a route for rapid production of AGNRs in large scale,which would benefit future applications in novel AGNRs-based semiconductor devices.

关键词： armchair graphene nanoribbons(AGNRs) microwave heating single-walled carbon nanotubes(SWCNTs) Raman spectroscopy

Design, Synthesis and Antitumor Activity of Pyrrolopyrazinone-chalcone Hybrids

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Chemical Research in Chinese Universities 2014年第4期30卷 624-631页

作者： MENG Ying zhang hongwei LIU Zehua ZENG Shanchao SUN Chiyu zhang Lijuan ZHAO Mingming WANG Guan JIANG Mengying SHI Wei SONG Hongrui 10016 P. R. China Key Laboratory for Molecular Enzymology & Engineering Ministry of Education Jilin University Changchun 130012 P. R. China

A series of pyrrolopyrazinone-chalcone hybrids（12a-12q） was designed,synthesized and screened for their antitumor activity against SKOV-3,A549 and HeLa cell lines in *** with the pyrrolopyrazinone（10a） and 5-fluorouracil（5-FU）,nearly all the tested compounds showed significantly-improved antitumor *** most promising compounds 12e and 12k（IC50=0.25 and 0.88 μmol/L） respectively show activities of 123and 35 times that of compound 10a（IC50=30.74 μmol/L） against HeLa cell *** result reveals that the presence of chalcone moiety is beneficial to their activity and selectivity.

关键词： Pyrrolopyrazinone-chalcone hybrid Antitumor Marine sponge Combination principle

Cloning of a new allele of ZmAMP1 and evaluation of its breeding value in hybrid maize

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The Crop Journal 2023年第1期11卷 157-165页

作者： Pingxi Wang Yuan Yang Dongdong Li Jialiang Xu Riliang Gu Jun Zheng Junjie Fu Jianhua Wang hongwei zhang Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081China Center for Seed Science and Technology College of Agronomy and BiotechnologyChina Agricultural UniversityBeijing 100193China College of Life Science and Technology Henan Institute of Science and TechnologyXinxiang 453003HenanChina National Nanfan Research Institute(Sanya) Chinese Academy of Agricultural SciencesSanya 572024HainanChina

Gene resources associated with plant stature and flowering time are invaluable for maize *** this study,using an F2:3population derived from a natural semi-dwarf mutant grmm and a normal inbred line Si 273,we identified a major pleiotropic QTL on the distal long arm of chromosome 1(qPH1_dla),and found that qPH1_dla controlled plant height,flowering time,ear and yield ***1_dla was finemapped to a 16 kb interval containing ZmAMP1,which was annotated as a glutamate *** tests using two independent allelic mutants confirmed that ZmAMP1 was the causal *** quantitative PCR and genomic sequence analysis suggested that a nonsynonymous mutation at the598th base of ZmAMP1 gene was the causal sequence variant for the dwarfism of *** novel ZmAMP1 allele was named ZmAMP1_*** sequencing using two pairs of near isogenic lines(NILs)showed that 84 up-regulated and 68 down-regulated genes in dwarf NILs were enriched in 15metabolic ***,introgression of ZmAMP1_grmm into Zhengdan 958 and Xianyu 335 generated two improved *** field tests,they were semi-dwarf,early-flowering,lodging-resistant,and high-yielding under high-density planting conditions,suggesting that ZmAMP1_grmm is a promising Green Revolution gene for maize hybrid breeding.

关键词： Maize Plant height ZmAMP1 Green revolution

Quasi-synchronization of fractional-order complex networks with random coupling via quantized control

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Chinese Physics B 2023年第11期32卷 355-363页

作者：张红伟程然丁大为 School of Electronics and Information Engineering Anhui UniversityHefei 230601China

We investigate the quasi-synchronization of fractional-order complex networks(FCNs) with random coupling via quantized control. Firstly, based on the logarithmic quantizer theory and the Lyapunov stability theory, a new quantized feedback controller, which can make all nodes of complex networks quasi-synchronization and eliminate the disturbance of random coupling in the system state, is designed under non-delay conditions. Secondly, we extend the theoretical results under non-delay conditions to time-varying delay conditions and design another form of quantization feedback controller to ensure that the network achieves quasi-synchronization. Furthermore, the error bound of quasi-synchronization is ***, we verify the accuracy of our results using two numerical simulation examples.

关键词： complex network fractional-order random coupling time-varying delay quasi-synchronization quantized control

Stereo mapping of Ming Great Wall with remote sensing

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Chinese Science Bulletin 2010年第21期55卷 2290-2294页

作者： CHEN Jun JIN ShuPing LIAO AnPing ZHAO YouSong zhang hongwei RONG DaWei YANG ZhaoJun National Geomatics Center of China Beijing 100830 China Chinese Academy of Culture Heritage Beijing 100029 China

Listed by UNESCO in 1987 as a World Heritage site,the world-famous Ming Great Wall stretches several thousands of kilometers across northern China,and served as a massive military defensive system which in recent times has a unique historical,artistic and scientific *** to historical reasons and lack of advanced technologies,construction resources and conservation status of Ming Great Wall have not been investigated in any systematic manner;indeed,the extent of the Great Wall has not even been *** has resulted in a shortage of reliable first-hand scientific information on actual size,spatially resource distribution and preservation status of this World Heritage *** by the urgent need to establish protection,research,renovation and management of Ming Great Wall,a comprehensive investigation and spatial mapping was jointly organized and completed by the State Bureau of Survey and Mapping and State Administration of Culture *** resolution digital stereo models at 1:10000 map scale covering the whole length of the Ming Great Wall have been created by photogrammetric reconstruction using nearly ten thousand aerial *** distribution and attributes of the wall sections,trenches and various subsidiary facilities in the surroundings of the Great Wall were measured with the help of digital photogrammetry workstations and results from field *** and precise information about the Ming Great Wall has now been obtained and documented,including surface lengths,resource distribution,and preservation *** example,the total length of Ming Great Wall is 8851.8 km,of which 6259.6 km is of actual wall,2232.5 km of natural terrain,and 359.7 km of *** category lengths,1828.8 km is constructed of stone,3411.3 km of earth,249.6 km in brick,197.5 km of cliff wall and the rest 572.4 km of other *** information provides the scientific basis and strong platform in helping to delineate areas needing protection,in planni

关键词：数字立体声测绘管理长城数字摄影测量工作站联合国教科文组织世界遗产遥感科学价值

Simulation on Peak-to-Average Power Ratio for Orthogonal Frequency Division Multiplexing

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Wuhan University Journal of Natural Sciences 2006年第6期11卷 1873-1876页

作者： SHAN Weifeng MENG Baohong LIU Ningning LI Hui zhang hongwei Department of Command Communication and Command Academy Wuhan 430010 Hubei China

Clipping is a simple and convenient PAPR （peak-to-average power ratio） reduction method for high speed OFDM （orthogonal frequency division multiplexing） communication system. In this paper, we propose a new PAPR reduction method for Wireless-MAN（metropolitan area network）-OFDM system based on IEEE 802.16, which is over-sampling clipping arithmetic. Simulation and performance of the over-samples clipping＇s PAPR reduction capability, BER effect is given. The simulation indicates that the PAPR of at least 99.9% OFDM symbol is below 6dB after 2 Nyquist rate clipping, and the performance of BER has 1dB SNR（signal noise ratio） loss. The results prove that this method has better capacity to reducing PAPR. So it can be well used in WMAN-OFDM system.

关键词： peak-to-average power ratio OFDM(orthogonal frequency divisior multiplexing) clipping

Long-term follow-up of vagus nerve stimulation in drug-resistant KCNT1-related epilepsy: a case presentation

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Acta Epileptologica 2022年第4期5卷 275-280页

作者： Meng Wang Guifu Geng Yao Meng hongwei zhang Zaifen Gao Jianguo Shi Department of Epilepsy Center Children’s Hospital Affiliated to Shandong UniversityJinan Children’s HospitalJinan250000China Department of Functional Neurosurgery Children’s Hospital Affiliated to Shandong UniversityJinan Children’s HospitalJinan250000China

Background The KCNT1 gene encodes a Na+-activated K+***-of-function mutations of KCNT1 lead to autosomal dominant sleep-related hypermotor epilepsy,early-onset epileptic encephalopathy,focal epilepsy and other epileptic *** this paper,we report a boy carrying a KCNT1 gene mutation,who presented with drug-resistant focal-onset *** had decreased seizure frequency and improvement of background changes in electroencephalography(EEG)after vagus nerve stimulation(VNS).Case presentation The case was a nonverbal 9-year-old male who presented with drug-resistant focal-onset seizures since age 3 and had underwent VNS therapy for 2 *** had hypermotor symptoms,automatism and bilateral asymmetric tonic seizures with cognitive decline and aphasis from age *** patient had a variety of seizure types that only occurred at *** most common seizure type was automatisms,and ictal video EEG showed high-amplitude delta waves,followed by a fast rhythmic sharp activity in the mesial frontal and bitemporal *** patient was diagnosed with KCNT1-related epilepsy,epileptic encephalopathy and cognitive *** was refractory to multiple anti-seizure medicines(ASM)and ketogenic *** VNS treatment at age 7,the frequency of seizures was reduced significantly and EEG was improved in background *** Children with KCNT1-related epilepsy usually have early onset of disease,are nonverbal,and are refractory to *** boy with drug-resistant KCNT1-related epilepsy showed significantly reduced seizure frequency after *** report may provide reference for management of cases of KCNT1-related epilepsy.

关键词： Vagus nerve stimulation KCNT1 gene Epileptic encephalopathy KCNT1-related epilepsy

One Method to Derivate Coulomb’s Law between Two Charges

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Journal of Applied Mathematics and Physics 2020年第12期8卷 2880-2885页

作者： hongwei zhang Shimeng Feng Shanghai Qibaodwight High School Shanghai China School of Physics and Astronomy Shanghai Jiao Tong University Shanghai China

In electromagnetics, Coulomb’s law is a very classic formula. Almost all textbooks give this formula, but none of them give a detailed corresponding theoretical derivation. In order for beginners of physics to better understand the physical meaning of this formula, we explored the source, the physical model and mechanism of this formula. Based on the principle that the interaction between two different fields can generate energy density, which is equal to the pressure, we analyzed the distribution of the electric field energy density as well as the corresponding pressure on the charged surface. Through the rigorous mathematical derivation, we give the theoretical derivation of this formula.

关键词： Electrostatic Force Energy Density Pressure Coulomb’s Law

Pathway-selective suppression of chemokine receptor signaling in B cells by LPS through downregulation of PLC-b2

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Cellular & Molecular Immunology 2010年第6期7卷 428-439页

作者： Aiko-Konno Shirakawa Fang Liao hongwei H zhang Michael N Hedrick Satya P Singh Dianqing Wu Joshua M Farber Inflammation Biology Section Laboratory of Molecular ImmunologyNational Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaMDUSA Department of Pharmacology Yale University School of MedicineNew HavenCTUSA

Lymphocyte activation leads to changes in chemokine receptor *** are limited data,however,on how lymphocyte activators can alter chemokine signaling by affecting downstream *** hypothesized that B cell-activating agents might alter chemokine responses by affecting downstream signal transducers,and that such effects might differ depending on the *** found that activating mouse B cells using either anti-IgM or lipopolysaccharide(LPS)increased the surface expression of CCR6 and CCR7 with large increases in chemotaxis to their cognate *** contrast,while anti-IgM also led to enhanced calcium responses,LPS-treated cells showed only small changes in calcium signaling as compared with cells that were freshly *** particular interest,we found that LPS caused a reduction in the level of B-cell phospholipase C(PLC)-b2 mRNA and *** obtained using PLC-b22/2 mice showed that the b2 isoform mediates close to one-half the chemokine-induced calcium signal in resting and anti-IgM-activated B cells,and we found that calcium signals in the LPS-treated cells were boosted by increasing the level of PLC-b2 using transfection,consistent with a functional effect of downregulating ***,our results show activator-specific effects on responses through B-cell chemokine receptors that are mediated by quantitative changes in a downstream signal-transducing protein,revealing an activity for LPS as a downregulator of PLC-b2,and a novel mechanism for controlling chemokine-induced signals in lymphocytes.

关键词： B cells calcium chemokine chemotaxis GPCR