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Dicyclopentyl azodicarboxylate(DCpAD):A new alternative azo-reagent for the Mitsunobu reaction

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Chinese Chemical Letters 2011年第9期22卷 1047-1050页

作者： Jian Hai Yang Li Yan Dai Xiao zhong wang ying Qi Chen Department of Chemical and Biological Engineering Zhejiang University Hangzhou 310027 China

Dicyclopentyl azodicarboxylate is introduced as a new azo-reagent which can be conveniently prepared in two steps and be used in the Mitsunobu reaction. Though there are no distinct difference of reactivity between DC... 详细信息

关键词： Dicyclopentyl azodicarboxylatc Mitsunobu reaction Azo-reagent

Low-latency Data Gathering with Reliability Guaranteeing in Heterogeneous Wireless Sensor Networks

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International Journal of Automation and computing 2020年第3期17卷 439-452页

作者： Tian-Yun Shi Jian Li Xin-Chun Jia Wei Bai zhong-ying wang Dong Zhou Institute of Computing Technology China Academy of Railway SciencesBeijing 100081China School of Mathematical Sciences Shanxi UniversityTaiyuan 030006China

In order to achieve low-latency and high-reliability data gathering in heterogeneous wireless sensor networks(HWSNs),the problem of multi-channel-based data gathering with minimum latency(MCDGML),which associates with construction of data gathering trees,channel allocation,power assignment of nodes and link scheduling,is formulated as an optimization problem in this ***,the optimization problem is proved to be *** make the problem tractable,firstly,a multi-channel-based low-latency(MCLL)algorithm that constructs data gathering trees is proposed by optimizing the topology of ***,a maximum links scheduling(MLS)algorithm is proposed to further reduce the latency of data gathering,which ensures that the signal to interference plus noise ratio(SINR)of all scheduled links is not less than a certain threshold to guarantee the reliability of *** addition,considering the interruption problem of data gathering caused by dead nodes or failed links,a robust mechanism is proposed by selecting certain assistant nodes based on the defined one-hop weight.A number of simulation results show that our algorithms can achieve a lower data gathering latency than some comparable data gathering algorithms while guaranteeing the reliability of links,and a higher packet arrival rate at the sink node can be achieved when the proposed algorithms are performed with the robust mechanism.

关键词： Heterogeneous wireless sensor networks(HWSNs) data gathering tree multi-channel power assignment link scheduling

A Dielectric Ink Combining Acrylate and Cyanate Moieties for Inkjet 3D Printing with Good Thermal Stability

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Chinese Journal of Polymer Science 2024年第6期42卷 766-774页

作者： Yi-Xuan Li Liang-ying Wu Yan Yang Yao-zhong Lu zhong-ying Ji Yu-Xiong Guo Xiao-Long wang Qiao-Sheng Pu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsLanzhou730000China Lanzhou Traditional Chinese Medicine Hospital of Orthopedics and Traumatology Lanzhou730000China Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai Yantai Zhongke Research Institute of Advanced Materials and Green Chemical EngineeringYantai264006China

Inkjet 3D printing has potential in the additive manufacturing of electronic circuits and ***,inks that can be used for printing layers with T5%>300℃ or hardness>200 MPa have been rarely *** ester(CE)polymers have excellent thermal stability,high strength,and low shrinkage compared to other common dielectric inks for inkjet 3D printing,but cannot be quickly shaped by ultraviolet(UV)irradiation or thermal *** CEs with UV-curable monomers may be a possible way to accelerate crosslinking,but there are challenges from the adverse effects of the dilution of both *** this study,dielectric inks with acrylate and cyanate moieties were *** low viscosity and surface tension of the CE precursor(Bisphenol E cyanate ester)were combined with photocurable acrylate diluent monomers and cross-linker to realize an ink suitable for inkjet 3D *** internal dual three-dimensional cross-linked network structure resin was prepared by a combination of photocuring and thermal curing with T5%up to 326.69℃,hardness up to 431.84 MPa,dielectric constant of 2.70 at 8 GHz,and shrinkage of 1.64%.The developed dielectric inks can be applied to the 3D printing of printed circuit boards and other electronic devices that require dielectric properties.

关键词： Inkjet printing Cyanate ester resin 3D doubly cross-linked network Good thermal stability

A Novel Method for Forecasting Freak Wave Occurrence in A Short Crested Coastal Sea

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China Ocean Engineering 2024年第1期38卷 104-116页

作者： wang ying-guang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Ocean and Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China

In order to forecast the distribution of crest amplitudes and the occurrence of freak waves in a short crested coastal sea,a novel transformed linear simulation method is initially proposed in this paper.A Hermite transformation model expressed as a monotonic cubic polynomial serves as the foundation for the novel simulation *** wave crest amplitude exceedance probabilities of two sea states-one with a directional wave spectrum based on the measured wave elevation data at the Yura coast and the other with a typical directional JONSWAP wave spectrum-have been predicted using the novel simulation method that has been *** likelihood that a particular critical wave crest amplitude will be exceeded is directly correlated with the probability that freak waves will *** is shown that the novel simulation approach suggested can provide predictions that are more precise than those obtained from the Rayleigh crest amplitude distribution model,the Jahns and Wheeler crest amplitude distribution model,or the conventional linear simulation *** study also demonstrated that the nonlinear simulation method is less effective than the novel simulation method in terms of efficiency.

关键词： wave crest amplitude freak waves short crested sea transformed linear simulation

Computed tomography-based radiomics diagnostic approach for differential diagnosis between early-and late-stage pancreatic ductal adenocarcinoma

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1256-1267页

作者： Shuai Ren Li-Chao Qian ying-ying Cao Marcus J Daniels Li-Na Song ying Tian zhong-Qiu wang Department of Radiology Jiangsu Province Hospital of Chinese MedicineAffiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Geratology Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese MedicineNanjing 210022Jiangsu ProvinceChina Department of Radiology NYU Langone HealthNew YorkNY 10016United States

BACKGROUND One of the primary reasons for the dismal survival rates in pancreatic ductal adenocarcinoma(PDAC)is that most patients are usually diagnosed at late *** is an urgent unmet clinical need to identify and develop diagnostic methods that could precisely detect PDAC at its earliest *** A total of 71 patients with pathologically proved PDAC based on surgical resection who underwent contrast-enhanced computed tomography(CT)within 30 d prior to surgery were included in the *** staging was performed in accordance with the 8th edition of the American Joint Committee on Cancer staging *** features were extracted from the region of interest(ROI)for each patient using Analysis Kit *** most important and predictive radiomics features were selected using Mann-Whitney U test,univar-iate logistic regression analysis,and minimum redundancy maximum relevance(MRMR)*** forest(RF)method was used to construct the radiomics model,and 10-times leave group out cross-validation(LGOCV)method was used to validate the robustness and reproducibility of the *** A total of 792 radiomics features(396 from late arterial phase and 396 from portal venous phase)were extracted from the ROI for each patient using Analysis Kit *** most important and predictive features were selected using Mann-Whitney U test,univariate logistic regression analysis,and MRMR *** method was used to construct the radiomics model with the nine most predictive radiomics features,which showed a high discriminative ability with 97.7%accuracy,97.6%sensitivity,97.8%specificity,98.4%positive predictive value,and 96.8%negative predictive *** radiomics model was proved to be robust and reproducible using 10-times LGOCV method with an average area under the curve of 0.75 by the average performance of the 10 newly built *** The radiomics model based on CT could serve as a promising non-invasive method in differential diag

关键词： Pancreatic ductal adenocarcinoma Radiomics Computed tomography American Joint Committee on Cancer staging

Experimental and computational analysis of the structure-activity relationship of ionic gel electrolytes based on bistrifluoromethanesulfonimide salts for supercapacitors

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Journal of Materiomics 2024年第6期10卷 1222-1233页

作者： Wei Chen ying Wei Xiuling Dong zhong-Xia wang Zheng Xing Qingguo Zhang Xiang Liu College of Chemistry and Materials Engineering Bohai UniversityJinzhou121013LiaoningChina College of Chemistry and Chemical Engineering Gannan Normal UniversityGanzhou341000JiangxiChina Institute of Medicine&Chemical Engineering Zhenjiang CollegeZhenjiang212028JiangsuChina

Ionic gel(IG)electrolytes are emerging as promising components for the development of next-generation supercapacitors(SCs),offering benefits in terms of safety,cost-effectiveness,and *** ionic conductivity,stability,and mechanical properties of the gel electrolyte are relevant factors to be considered and the key to improving the performance of the ***,the structure–activity relationship between the internal structure of IGs and their SC properties is not fully *** the current study,the intuitive and regular structure–activity relationship between the structure and properties of IGs was revealed via combining computational simulation and *** terms of conductivity,the ionic liquid(IL)([EMIM][TFSI])in the IG has a high self-diffusion coefficient calculated by molecular dynamics simulation(MDS),which is conductive to transfer and then improves the *** radial distribution function of the MDS shows that the larger the g(r)between the particles in the polymer network,the stronger the *** stability,IGs based on[EMIM][TFSI]and[EOMIM][TFSI]ILs have higher density functional theory calculated binding energy,which is reflected in the excellent thermal stability and excellent capacitor cycle *** on the internal pore size distribution and stress-strain characterization of the gel network([ME3MePy][TFSI]and[BMIM][TFSI]as additives),the highly crosslinked aggregate network significantly reduces the internal mesoporous distribution and plays a leading role in improving the mechanical properties of the *** using this strategy,it will be possible to design the ideal structure of the IG and achieve excellent performance.

关键词： Ionic gel electrolytes Density functional theory Molecular dynamics simulation Self-diffusion coefficient Mean square displacement

Rapidly growing primordial black holes as seeds of the massive high-redshift JWST Galaxies

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 139-146页

作者： Guan-Wen Yuan Lei Lei Yuan-Zhu wang Bo wang Yi-ying wang Chao Chen Zhao-Qiang Shen Yi-Fu Cai Yi-zhong Fan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Deep Space Exploration Laboratory/Department of Astronomy School of Physical SciencesUniversity of Science and Technology of ChinaHefei 230026China Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina

A group of massive galaxies at redshifts of z■7 have been recently detected by the James Webb Space Telescope(JWST),which were unexpected to form at such an early time within the standard Big Bang *** this work,we propose that this puzzle can be explained by the presence of some primordial black holes(PBHs)with a mass of~1000M_(⊙).These PBHs act as seeds for early galaxy formation with masses of~10^(8)-10^(10)M_(⊙)at high redshift,hence accounting for the JWST *** use a hierarchical Bayesian inference framework to constrain the PBH mass distribution models,and find that the Lognormal model with the M_(c)~750M_(⊙)is preferred over other *** rapidly growing BHs are expected to have strong radiation and may appear as high-redshift compact objects,similar to those recently discovered by *** we focused on PBHs in this work,the bound on the initial mass of the seed black holes remains robust even if they were formed through astrophysical channels.

关键词： primordial black hole dark matter halo black hole accretion primordial galaxies

Underwater Pulse Waveform Recognition Based on Hash Aggregate Discriminant Network

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Journal of Ocean University of China 2024年第3期23卷 654-660页

作者： wang Fangchen zhong Guoqiang wang Liang College of Computer Science and Technology Ocean University of ChinaQingdao 266100China College of Marine Technology Ocean University of ChinaQingdao 266100China

Underwater pulse waveform recognition is an important method for underwater object *** existing works focus on the application of traditional pattern recognition methods,which ignore the time-and space-varying characteristics in sound propagation channels and cannot easily extract valuable waveform *** propagation channels in seawater are time-and space-varying convolutional *** the extraction of the waveform features of underwater acoustic signals,the effect of high-accuracy underwater acoustic signal recognition is identified by eliminating the influence of time-and space-varying convolutional channels to the greatest extent *** propose a hash aggregate discriminative network(HADN),which combines hash learning and deep learning to minimize the time-and space-varying effects on convolutional channels and adaptively learns effective underwater waveform features to achieve high-accuracy underwater pulse waveform *** the extraction of the hash features of acoustic signals,a discrete constraint between clusters within a hash feature class is *** constraint can ensure that the influence of convolutional channels on hash features is *** addition,we design a new loss function called aggregate discriminative loss(AD-loss).The use of AD-loss and softmax-loss can increase the discriminativeness of the learned hash *** results show that on pool and ocean datasets,which were collected in pools and oceans,respectively,by using acoustic collectors,the proposed HADN performs better than other comparative models in terms of accuracy and mAP.

关键词： convolutional channel hash aggregate discriminative network aggregate discriminant loss waveform recognition

Effect of interplanetary magnetic field B_(x)on the polar electrojets as observed by CHAMP and Swarm satellites

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Earth and Planetary Physics 2024年第2期8卷 382-390页

作者： Hui wang ChengZhi wang YunFang zhong Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

Based on 16 years of magnetic field observations from CHAMP and Swarm satellites,this study investigates the influence of the Interplanetary Magnetic Field(IMF)Bx component on the location and peak current density of the polar electrojets(PEJs).We find that the IMF Bx displays obvious local time,seasonal,and hemispherical effects on the PEJs,as follows:(1)Compared to other local times,its influence is weakest at dawn and dusk.(2)In the midnight sectors of both hemispheres,the IMF Bx tends to amplify the westward PEJ when it is0 in the Southern Hemisphere;this effect is relatively stronger in the local winter hemisphere.(3)At noontime,the IMF Bx intensifies the eastward current when it is0,it reduces the westward current;this effect is notably more prominent in the local summer hemisphere.(4)Moreover,the noontime eastward current shifts towards higher latitudes,while the midnight westward current migrates towards lower latitudes when IMF Bx is0 in the Southern Hemisphere.

关键词： polar electrojet interplanetary magnetic field Bx local time asymmetry hemispheric difference