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Property of alumina to adsorb long chain normal-paraffinhydrocarbons

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Chinese Science Bulletin 1998年第2期43卷 126-128页

作者： yongzhi li Xianliang Deng Weile Yu Luoyang Petrochem Engn Corp Petr Refining Res Inst Luoyang 471023 Peoples R China Lanzhou Inst Chem Phys Lanzhou 730000 Peoples R China

That alumina can strongly absorb long chain normal_paraffin hydrocarbon was found when alumina was used in the preparative group_type separation of heavy petroleum fractions. The reason for the above property of alumina may be that the normal_paraffin hydrocarbons can extend closely on the alumina surface. One molecule of long chain normal_paraffin hydrocarbon can be adsorbed by many active sites of alumina surface. The longer chain normal_paraffin hydrocarbon can be adsorbed by more active sites of alumina surface; this results in the longer chain normal_paraffin hydrocarbon has a stronger adsorption on alumina.

关键词： alumina adsorption property long chain normal-paraffin hydrocarbons.

An advanced five-unknown higher-order theory for free vibration of composite and sandwich plates

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Chinese Journal of Aeronautics 2021年第9期34卷 104-118页

作者： Zhen WU Rui MA yongzhi li Yushan XIAO Jie MEI School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China

Accurate prediction of dynamic characteristics is quite critical to understand the strength of layered ***,the existing five-unknown higher-order theories encounter difficulties to forecast accurately the dynamic response of sandwich ***,a new five-unknown higher-order theory is developed for free vibration analysis of composite and sandwich plates,which possesses the same degree of freedom as those of other five-unknown higherorder *** developed model can meet beforehand interlaminar continuity conditions and the free-surface conditions of transverse shear *** assess capability of the proposed model,analytical solution for such composite structures with simply-supported conditions has been presented by employing Hamilton’s principle,which is utilized for analysis of mechanical behaviors of composite and sandwich *** with the three-dimensional(3 D)elasticity solutions,3 D finite element results and the results obtained from the chosen five-unknown higher-order models,the proposed model can yield accurately natural frequencies of composite and sandwich *** for the thick plates,the higher-order frequencies calculated from the proposed model are in good agreement with the 3 D finite element *** studying effect of the thickness/length ratios on natural frequencies,it is found that the proposed model is adaptable to predicting natural frequencies of the sandwich plates with the thickness/length ratios between 1/4 and 1/*** addition,some factors influencing accuracy of five-unknown higher-order models have been investigated in ***,by means of numerical analysis and discussion,some conclusions have been drawn as well,which can serve as a reference for other investigators.

关键词： Analytical solution Five-unknown Free vibrations Higher-order theory Sandwich plates

Validated,Rapid and Sensitive HPLC-MS/MS Method for Determination of 7,4'-Dihydroxylflavone in Rat Plasma and Its Application to Preliminary Pharmacokinetics

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Journal of Beijing Institute of Technology 2019年第4期28卷 731-738页

作者： Shibo Wang Panpan li yongzhi li Jiaping Wang Yujuan li School of life Science Beijing Institute of TechnologyBeijing 100081China China Astronaut Research and Training Centre Beijing 100094China

A sensitive,specific and rapid high-performance liquid chromatography-electronic spray ionization-tandem mass spectrometric method was developed and validated for the determination of 7,4'-dihydroxylflavone(7,4'-DHF)in rat ***(internal standard,IS)was added in the collected plasma samples and subsided together by a simple one-step protein precipitation using acetonitrile-methanol(1:1,v/v).Chromatographic separation was performed on an Agilent Zorbax XDB C18 chromatography column and gradient elution with the mobile phase consisting of methanol and 0.1%formic acid was *** mass spectrometric detection was performed by negative ion electro-spray ionization in multiple selected reactions monitoring(MRM)mode,with the transitions of m/z 253.1→113.0 for 7,4'-DHF and m/z 268.9→158.8 for *** calibration curve has liner relationship over the concentration range of ***/mL(r=0.995.4).The intra-and inter-day precision(RSD%)was less than 10%,and the accuracy(RE%,relative error)ranged from-5.2%to 8.0%.The fully validated method was applied to the pharmacokinetics(PK)of 7,4'-dihydroxylflavone(7,4'-DHF)in rat plasma after oral administration(two doses:15 and ***/kg)and intravenous injection(***/kg).The result showed that Tmax and Cmax was 1.33±0.29.h and 0.12±***/mL(***/kg),and 1.17±0.29.h and 0.17±***/mL(***/kg),*** bioavailability was 0.078%(***/kg)and 0.070%(***/kg),respectively.

关键词： 7,4'-dihydroxylflavone HPLC-MS/MS pharmacokinetics bioavailability

Impact of aperture on dynamic response of sandwich plates with aluminium face-sheets and PMI core based on an alternative finite element formulation and experiments

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Chinese Journal of Aeronautics 2022年第4期35卷 266-280页

作者： Zhen WU yongzhi li Dongjian ZHANG Jie MEI Xiaohui REN Rui MA School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China School of Mechanical Engineering Xi an Aeronautical UniversityXi'an 710065China

Apertures generally exist in the sandwich structures attributing to mechanical connection and lightweight, which might induce failure of such structures. Thus, it is required to realize the impact of aperture on mechanical behaviors of sandwich structures. If transverse shear deformations are unable to be described accurately, the reasonable prediction of dynamic behaviors of the form-core sandwich plates with apertures will meet severe challenges due to a large difference of transverse shear modulus at the adjacent layers. Thereby, such issue is less studied by using the efficient models and experimental testing, so an alternative sinusoidal-type finite element formulation is to be proposed to precisely predict dynamic response of the form-core sandwich structures with apertures. The proposed finite element formulation can meet beforehand compatible conditions of transverse shear stresses at the interfaces of adjacent laminates. In order to appraise strictly capability of the proposed model, experimental tests on natural frequencies of three groups of specimens with different apertures have been carried out. Moreover, four specimens in each group are tested to reduce the testing errors, which is less reported in the published literature. In addition,three-dimensional Finite Element Method(3-D FEM) is also selected to account for the good performance of the present model. Finally, the impact of aperture diameter on the natural frequencies of the sandwich structures is both experimentally and numerically investigated, which can serve as a reference for other researchers.

关键词： Dynamic response Sandwich plates Higher-order theory Experimental tests Finite element method

Defect-induced electron rich nanodomains in CoSe_(0.5)S_(1.5)/GA realize fast ion migration kinetics as sodium-ion capacitor anode

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Journal of Energy Chemistry 2023年第12期87卷 583-593,I0014页

作者： Tianlin li Danyang Zhao Binghui Du Qing Yin yongzhi li Xiaolan Xue Fuxiang Wei Jiqiu Qi Yanwei Sui China University of Mining and Technology Xuzhou 221116JiangsuChina Jiangsu Province Engineering Laboratory of High-Efficient Energy Storage Technology and Equipment School of Materials Science and PhysicsChina University of Mining and TechnologyXuzhou 221116JiangsuChina

Optimizing charge migration and alleviating volume expansion in anode materials are the key to improve the electrochemical performance for sodium-ion storage ***,a hierarchical porous conducting matrix confining defect-rich selenium doped cobalt dichalcogenide(CoSe_(0.5)S_(1.5)/GA)is constructed as a promising SICs anode based on the guidance of theoretical calculation *** increased defect concentration significantly enhanced the disorder degree of the compound and presented electron aggregation around the S atoms,which effectively modulated the electronic structure,further enabling high rate and ultra-capacity sodium ***,strong interfacial coupling could construct spatial constraint to alleviate volume expansion as well as maintain electrode integrity and *** CoSe_(0.5)S_(1.5)/GA electrode can deliver a high capacity of 310.1 mA h g^(-1)after 2000 cycles at 1 A g^(-1),and the CoSe_(0.5)S_(1.5)/GA//AC sodium ion capacitor can exhibit an outstanding energy density of 237.5 W h kg^(-1).A series of characterization and theoretical calculation convincingly reveal that the defect moieties can regulate the Na^(+)storage and diffusion kinetics,which prove that our defect manufacture coupling with space-confined strategy can provide deep insights into the development of high-performance Na^(+)storage devices.

关键词： Sodium-ion capacitors Defect manufacture Electron accumulation Carrier kinetic

Channel capacity investigation of a linear massive MIMO system using spherical wave model in LOS scenarios

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Science China(Information Sciences) 2016年第2期59卷 45-59页

作者： liu liU David W.MATOLAK Cheng TAO yongzhi li Bo AI Houjin CHEN Institute of Broadband Wireless Mobile Communications Beijing Jiaotong University Department of Electrical Engineering University of South Carolina National Mobile Communications Research Laboratory Southeast University

Massive multiple-input multiple-output(MIMO) is a key technology for the 5th generation(5G)of wireless communication systems. The traditional plane wave channel model(PWM) is often not suitable for the large antenna structure, and in certain cases should be replaced by the more accurate spherical wave model(SWM). By using the spherical wave characterization method, this paper investigates the channel capacity performance of a linear massive MIMO system in line-of-sight(LOS) scenarios. Two types of access settings, the point to point(PTP) system and multi-user(MU) system, are considered. In the PTP setting, a geometrical optimization is performed to obtain configurations that are able to generate a full rank channel matrix for a linear massive MIMO system, which yields full spatial diversity even in LOS scenarios. Compared with the approximate and commonly applied rank-1 PWM, this is very useful for fixed wireless access and radio relay systems requiring high throughput. For the MU case, we compare the eigenvalue distributions of the LOS channels using the plane wave and spherical wave characterization method, and sum rate results are obtained by Monte Carlo simulations. The results show that MU systems using the more realistic and accurate SWM can achieve a higher sum rate than results from the PWM. This is beneficial and informative when designing massive MIMO wireless networks.

关键词： massive MIMO channel model plane wave model spherical wave model channel capacity

Pre-training transformer with dual-branch context content module for table detection in document images

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虚拟现实与智能硬件（中英文） 2024年第5期6卷 408-420页

作者： yongzhi li Pengle ZHANG Meng SUN Jin HUANG Ruhan HE School of Computer Science and Artificial Intelligence Wuhan Textile UniversityWuhan 430064China School of Computer Science South-Central Minzu UniversityWuhan 430064China Hubei Provincial Engineering Research Center for Intelligent Textile and Fashion Wuhan Textile UniversityWuhan 430064China

Background Document images such as statistical reports and scientific journals are widely used in information *** detection of table areas in document images is an essential prerequisite for tasks such as information ***,because of the diversity in the shapes and sizes of tables,existing table detection methods adapted from general object detection algorithms,have not yet achieved satisfactory *** detection results might lead to the loss of critical *** Therefore,we propose a novel end-to-end trainable deep network combined with a self-supervised pretraining transformer for feature extraction to minimize incorrect *** better deal with table areas of different shapes and sizes,we added a dualbranch context content attention module(DCCAM)to high-dimensional features to extract context content information,thereby enhancing the network's ability to learn shape *** feature fusion at different scales,we replaced the original 3×3 convolution with a multilayer residual module,which contains enhanced gradient flow information to improve the feature representation and extraction *** We evaluated our method on public document datasets and compared it with previous methods,which achieved state-of-the-art results in terms of evaluation metrics such as recall and ***://***/Yong Z-Lee/TD-DCCAM.

关键词： Table detection Document image analysis Transformer Dilated convolution Deformable convolution Feature fusion

Strategy for Detecting Systemic Treatment Sensitivity of Primary liver Cancer Based on a Novel Infrared-emissive Organic Nanoparticle

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Chemical Research in Chinese Universities 2024年第1期40卷 145-152页

作者： WU Jun li yongzhi QIN Hanjiao GAO Ying YANG Bing SHENG Jiyao ZHANG Xuewen Department of Hepatobiliary and Pancreatic Surgery the Second Hospital of Jilin UniversityChangchun130022P.R.China Department of Radiation Oncology the Second Hospital of Jilin UniversityChangchun130022P.R.China State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun130012P.R.China

In this study,we synthesized an organic material with near-infrared emission capabilities:4-(2-(4-(9-(4-(diphenylamino)phenyl)naphtho[2,3-c][1,2,5]thiadiazol-4-yl)phenyl)-1H-phenol-1-ylidene)malononitrile(TPA).Furthermore,TPA-PEG2000 fluorescent nanoparticles were prepared via coating the shells with ***-PEG2000 exhibited strong near-infrared emission near 700 nm,with a photoluminescence quantum yield of 15.09%,indicating a high emission *** biology experiments have confirmed its low toxicity and excellent *** cholesterol and phospholipid levels in liver cancer cell membranes with low sensitivity or high drug resistance lead to increased rigidity,reduced membrane fluidity,reduced endocytic efficiency,and reduced ***,the uptake of TPA-PEG2000 nanoparticles into cells and the near-infrared fluorescence intensity can be used to evaluate the sensitivity of systemic liver cancer treatment in a simple and efficient manner.

关键词： Nanoparticle Near-infrared Fluorescence Systemic treatment sensitivity Cell membrane fluidity

A transformer generative adversarial network for multi-track music generation

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CAAI Transactions on Intelligence Technology 2022年第3期7卷 369-380页

作者： Cong Jin Tao Wang Xiaobing li Chu Jie Jiessie Tie Yun Tie Shan liu Ming Yan yongzhi li Junxian Wang Shenze Huang School of Information and Communication Engineering Communication University of ChinaBeijingChina School of Information and Engineering Zhengzhou UniversityZhengzhouChina Central Conservatory of Music BeijingChina Department of computer Science University of TorontoTorontoCanada School of Data Science and Media Intelligence Communication University of ChinaBeijingChina School of light Industry and Engineering South China University of TechnologyGuangzhouChina School of Animation and Digital Arts Communication University of ChinaBeijingChina

This study proposes a new generation network based on transformers and guided by the music theory to produce high-quality music *** this study,the decoding block of the transformer is used to learn the internal information of single-track music,and cross-track transformers are used to learn the information amongst the tracks of different musical instruments.A reward network based on the music theory is proposed,which optimizes the global and local loss objective functions while training and discriminating the network so that the reward network can provide a reliable adjustment method for the generation of the *** method of combining the reward network and cross entropy loss is used to guide the training of the generator and produce high-quality music *** with other multi-track music generation models,the experimental results verify the validity of the model.

关键词： artificial intelligence deep learning multimedia