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Chinese Chemical Letters 2016年第9期27卷 1505-1508页

作者： Shan-li Yi mei-chao li Xin-Quan Hu Wei-Min Mo Zhen-Lu Shen College of Chemical Engineering Zhejiang University of Technology

An efficient and convenient tert-butyl nitrite-catalyzed selective aerobic oxidation of thiols has been developed. Under the optimal reaction conditions, a number of thiol derivatives including aromatic thiols, heteroaromatic thiols and aliphatic thiols can be converted into their corresponding disulfides in good to excellent yields.

关键词： Oxidation Thiols Disulfides tert-Butyl nitrite Oxygen

A Weakly-Supervised Crowd Density Estimation Method Based on Two-Stage linear Feature Calibration

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 965-981页

作者： Yong-chao li Rui-Sheng Jia Ying-Xiang Hu Hong-mei Sun the College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao 266590 the Faculty of Information Science and Engineering Ocean University of ChinaQingdao 266000China the College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao 266590China the College of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210000China

In a crowd density estimation dataset,the annotation of crowd locations is an extremely laborious task,and they are not taken into the evaluation *** this paper,we aim to reduce the annotation cost of crowd datasets,and propose a crowd density estimation method based on weakly-supervised learning,in the absence of crowd position supervision information,which directly reduces the number of crowds by using the number of pedestrians in the image as the supervised *** this purpose,we design a new training method,which exploits the correlation between global and local image features by incremental learning to train the ***,we design a parent-child network(PC-Net)focusing on the global and local image respectively,and propose a linear feature calibration structure to train the PC-Net simultaneously,and the child network learns feature transfer factors and feature bias weights,and uses the transfer factors and bias weights to linearly feature calibrate the features extracted from the Parent network,to improve the convergence of the network by using local features hidden in the crowd *** addition,we use the pyramid vision transformer as the backbone of the PC-Net to extract crowd features at different levels,and design a global-local feature loss function(L2).We combine it with a crowd counting loss(LC)to enhance the sensitivity of the network to crowd features during the training process,which effectively improves the accuracy of crowd density *** experimental results show that the PC-Net significantly reduces the gap between fullysupervised and weakly-supervised crowd density estimation,and outperforms the comparison methods on five datasets of Shanghai Tech Part A,ShanghaiTech Part B,UCF_CC_50,UCF_QNRF and JHU-CROWD++.

关键词： Crowd density estimation linear feature calibration vision transformer weakly-supervision learning

Direct synthesis of imines by 9-azabicyclo-[3,3,1]nonan-N-oxyl/KOH-catalyzed aerobic oxidative coupling of alcohols and amines

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Chinese Chemical Letters 2018年第8期29卷 1269-1272页

作者： Yan Wan Jia-Qi Ma chao Hong mei-chao li li-Qun Jin Xin-Quan Hu Bao-Xiang Hu Wei-Min Mo Nan Sun Zhen-Lu Shen College of Chemical Engineering Zhejiang University of Technology

A simple and efficient method for preparation of imines by the oxidative coupling of benzyl alcohols with aromatic amines or aliphatic amines was developed. The reaction was catalyzed by 9-azabicyclo[3.3.1]nonan-N-oxyl（ABNO）/KOH with air as the economic and green oxidant. Under the optimal reaction conditions, a variety of imines were obtained in 80%-96% isolated yields.

关键词： Imines Benzyl alcohols Amines ABNO Air

Hybrid treatment of varied orthodontic appliances for a patient with skeletal class II and temporomandibular joint disorders:A case report and review of literature

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World Journal of Clinical Cases 2024年第2期12卷 431-442页

作者： Tong Lu li mei Bao-chao li Zi-Wei Huang Huang li Department of Orthodontics Nanjing Stomatological HospitalThe Affiliated Hospital of Medical SchoolNanjing UniversityNanjing 210008Jiangsu ProvinceChina Discipline of Orthodontics Department of Oral ScienceFaculty of DentistryUniversity of OtagoDunedin 9016New Zealand

BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a *** TMD symptoms occur during orthodontic treatment,an immediate pause of orthodontic adjustments is recommended;the treatment can resume when the symptoms are managed and *** SUMMARY This case report presents a patient(26-year-old,female)with angle class I,skeletal class II and *** treatment was a hybrid of clear aligners,fixed appliances and temporary anchorage devices(TADs).After 3 mo resting and treatment on her TMD,the patient’s TMD symptom alleviated,but her anterior occlusion displayed deep ***,the fixed appliances with TAD were used to correct the anterior deep-bite and level maxillary and mandibular deep *** the levelling,the patient showed dual bite with centric relation and maximum intercuspation discrepancy on her *** careful examination of temporomandibular joints(TMJ)position,the stable bite splint and Invisible Mandibular Advancement appliance were used to reconstruct her ***,the improved facial appearance and relatively stable occlusion were *** 1-year follow-up records showed there was no obvious change in TMJ morphology,and her occlusion was *** TMD screening and monitoring is of great clinical importance in the TMD susceptible *** treatment with clear aligners and fixed appliances and TADs is an effective treatment modality for the complex cases.

关键词： Temporomandibular disorder Skeletal class II Deep overbite Dual bite Invisible mandibular advancement appliance Case report

Electrochemical Reduction Characteristics of α-Nitronaphthalene inSulfuric Acid Solution

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Chinese Chemical Letters 1999年第11期10卷 945-948页

作者： Chun An MA Wen Km ZHANG Yong Ping GAN Hui HUANG mei chao li Shao Ping TONG(Department of Applied Chemistry, Zhejiang Universily of Technology, Hangzhou 310014) Department of Applied Chemistry Zhejiang University of Technology Hangzhou 310014 China

The'electrochemical reduction characteristics of α-nitronaphthalene in sulfuric acidsolution were first reported in this paper. The results showed that the 1-amino-5-naphthol can beprepared by electrodeduction from α-nitronaphthalene and reduction peak corresponding to thereaction of α-nitronaphthalene to 1-amino-3-naphthol was in the range of -0.40~0.60V(vs, D.H.E )on the amalgamated copper cathode in the presence of SnCl2 additives. The mechanism of α-nitronaphthalene electroreduction to 1-amino-5-naphthol was also investigated, the overallelectroreduction reaction was composed of two intermediate steps and two intermediate productsexisted in solution. The electrochemical reduction mechanism was similar to that of nitrobenzeneto para-aminophenol.

关键词： Electrochemical reduction α-nitronaphthalene 1-amino-5-naphthol.

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Petroleum Science 2024年第4期21卷 2383-2392页

作者： li-Ming Zhao Cai-Ping Lu Yang liu chao-chao li School of Mines China University of Mining and Technology Henan Institute of Geophysical Space Information

The similarities and differences in inherent mechanism and characteristic frequency between the onedimensional(1D) poroelastic model and the layered White model were investigated. This investigation was conducted under the assumption that the rock was homogenous and isotropic at the mesoscopic scale. For the inherent mechanism, both models resulted from quasi-static flow in a slow P-wave diffusion mode, and the differences between them originated from saturated fluids and boundary conditions. On the other hand, for the characteristic frequencies of the models, the characteristic frequency of the 1D poroelastic model was first modified because the elastic constant and formula for calculating it were misused and then compared to that of the layered White model. Both of them moved towards higher frequencies with increasing permeability and decreasing viscosity and diffusion length. The differences between them were due to the diffusion length. The diffusion length for the 1D poroelastic model was determined by the sample length, whereas that for the layered White model was determined by the length of the representative elementary volume(REV). Subsequently, a numerical example was presented to demonstrate the similarities and differences between the models. Finally, published experimental data were interpreted using the 1D poroelastic model combined with the Cole-Cole *** prediction of the combined model was in good agreement with the experimental data, thereby validating the effectiveness of the 1D poroelastic model. Furthermore, the modified characteristic frequency in our study was much closer to the experimental data than the previous prediction, validating the effectiveness of our modification of the characteristic frequency of the 1D poroelastic model. The investigation provided insight into the internal relationship between wave-induced fluid flow(WIFF)models at macroscopic and mesoscopic scales and can aid in a better understanding of the elastic modulus d

关键词： 1D poroelastic model Layered White model Quasi-static flow Slow P-wave diffusion Characteristic frequency Diffusion length

Enhancing the vertical resolution of lunar penetrating radar data using predictive deconvolution

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Earth and Planetary Physics 2024年第4期8卷 570-578页

作者： chao li JinHai Zhang CAS Engineering Laboratory for Deep Resources Equipment and Technology Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The Yutu-2 rover onboard the Chang’E-4 mission performed the first lunar penetrating radar detection on the farside of the *** high-frequency channel presented us with many unprecedented details of the subsurface structures within a depth of approximately 50 ***,it was still difficult to identify finer layers from the cluttered reflections and scattering *** applied deconvolution to improve the vertical resolution of the radar profile by extending the limited bandwidth associated with the emissive radar *** overcome the challenges arising from the mixed-phase wavelets and the problematic amplification of noise,we performed predictive deconvolution to remove the minimum-phase components from the Chang’E-4 dataset,followed by a comprehensive phase rotation to rectify phase anomalies in the radar ***,we implemented irreversible migration filtering to mitigate the noise and diminutive clutter echoes amplified by *** processed data showed evident enhancement of the vertical resolution with a widened bandwidth in the frequency domain and better signal clarity in the time domain,providing us with more undisputed details of subsurface structures near the Chang’E-4 landing site.

关键词： Chang’E-4 lunar penetrating radar data processing predictive deconvolution irreversible migration filtering

Constructing the Impossible Differential of Type-II GFN with Boolean Function and Its Application to WARP

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Chinese Journal of Electronics 2024年第1期33卷 80-89页

作者： Jiali SHI Guoqiang liU chao li College of liberal Arts and Sciences National University of Defense Technology Hunan Engineering Research Center of Commercial Cryptography Theory and Technology Innovation State Key Laboratory of Information Security Institute of Information Engineering

Type-Ⅱ generalized Feist el network(GFN) has attracted a lot of attention for its simplicity and high *** differential attack is one of the powerful cryptanalytic approaches for word-oriented block ciphers such as Feistel-like *** deduce the impossible differential of Type-Ⅱ GFN by analyzing the Boolean function in the middle *** main idea is to investigate the expression with the variable representing the plaintext(ciphertext) difference words for the internal state *** adopting the miss-in-the-middle approach,we can construct the impossible differential of Type-Ⅱ *** an illustration,we apply this approach to WARP,a lightweight 128-bit block cipher with a 128-bit key which was presented by Banik et *** SAC *** structure of WARP is a 32-branch Type-Ⅱ ***,we find two 21-round truncated impossible differentials and implement a 32-round key recovery attack on *** the 32-round key recovery attack on WARP,some observations are used to mount an effective *** the advantage of the early abort technique,the data,time,and memory complexities are 2125.69chosen plaintexts,2126.6832-round encryptions,and 2100-bit,*** the best of our knowledge,this is the best attack on WARP in the single-key scenario.

关键词： Ciphers Boolean functions Parallel processing Complexity theory

Auto-parametric resonance of a continuous-beam-bridge model under two-point periodic excitation:an experimental investigation and stability analysis

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 445-454页

作者： li Yuchun Shen chao liu Wei li Dong Department of Hydraulic Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this *** auto-parametric resonance experiment of the test model is conducted to observe and measure the auto-parametric resonance of a continuous beam under a two-point excitation on *** parametric vibration equation is established for the test model using the finite-element *** auto-parametric resonance stability of the structure is analyzed by using Newmark's method and the energy-growth exponent *** effects of the phase difference of the two-point excitation on the stability boundaries of auto-parametric resonance are studied for the test *** with the experiment,the numerical instability predictions of auto-parametric resonance are consistent with the test phenomena,and the numerical stability boundaries of auto-parametric resonance agree with the experimental *** a continuous beam bridge,when the ratio of multipoint excitation frequency(applied to the columns)to natural frequency of the continuous girder is approximately equal to 2,the continuous beam may undergo a strong auto-parametric *** with the present experiment and analysis,a hypothesis of Volgograd Bridge's serpentine vibration is discussed.

关键词： auto-parametric resonance continuous beam bridge model two-point excitation experimental investigation stability analysis vibration of Volgograd Bridge

A Review on Flow Boiling of the Fluid with Lower Boiling Point in Micro-Channels

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Journal of Thermal Science 2024年第1期33卷 1-17页

作者： ZHANG Zhiqiang JIA li DANG chao Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale School of MechanicalElectronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

With the advancement of micro machining technology,the high-heat-flux removal from miniature electronic devices and components has become an attractive *** boiling in micro-channels is an optimal form of heat transfer and has been widely employed in high-heat-flux cooling *** comprehensively-reviewed article focused on the available recent literatures of experimental investigation regarding the flow boiling heat transfer and unstable behaviors of the fluid with lower boiling point in *** thermal-fluid characteristics and potential heat transfer mechanisms of low-boiling-point fluids flow boiling in different narrow passages were summarized and *** literatures regarding the pressure drop and occurrence of the unstable phenomena existing in two-phase flow boiling process were also *** emphasis was given to the heat transfer enhancement methods as well as instability elimination,and various methods such as modification of surface and channel flow geometries were *** future researches in the field of micro-scale flow boiling were suggested.

关键词： flow boiling lower boiling point fluids mini/micro-channels instabilities enhancement suppression