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Macroscopic model and statistical model to characterize electromagnetic information of a digital coding metasurface

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National Science Review 2024年第3期11卷 159-171页

作者： Rui Wen shao jun Wei Wu Zheng Xing Wang Hui xu Han Qing Yang Qiang Cheng Tie jun Cui Institute of Electromagnetic Space Southeast University State Key Laboratory of Millimeter Waves Southeast University Peng Cheng Laboratory Pazhou Laboratory(Huangpu)

A digital coding metasurface is a platform connecting the digital space and electromagnetic wave space, and has therefore gained much attention due to its intriguing value in reshaping wireless channels and realizing new communication architectures. Correspondingly, there is an urgent need for electromagnetic information theory that reveals the upper limit of communication capacity and supports the accurate design of metasurface-based communication systems. To this end, we propose a macroscopic model and a statistical model of the digital coding metasurface. The macroscopic model uniformly accommodates both digital and electromagnetic aspects of the meta-atoms and predicts all possible scattered fields of the digital coding metasurface based on a small number of simulations or measurements. Full-wave simulations and experimental results show that the macroscopic model is feasible and accurate. A statistical model is further proposed to correlate the mutual coupling between meta-atoms with covariance and to calculate the entropy of the equivalent currents of digital coding metasurface. These two models can help reconfigurable intelligent surfaces achieve more accurate beamforming and channel estimation, and thus improve signal power and coverage. Moreover, the models will encourage the creation of a precoding codebook in metasurface-based direct digital modulation systems, with the aim of approaching the upper limit of channel capacity. With these two models, the concepts of current space and current entropy, as well as the analysis of information loss from the coding space to wave space, is established for the first time, helping to bridge the gap between the digital world and the physical world, and advancing developments of electromagnetic information theory and new-architecture wireless systems.

关键词： electromagnetic information theory current entropy current space digital coding metasurface macroscopic model statistical model

Researches on chemically modified electrode *** reduction of oxygen on iron porphyrin modified electrode

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Chinese Journal of Chemistry 1984年第2期2卷 95-104页

作者： DONG shao-jun xu Li-Juan MA Yue Changchun Institute of Applied Chemistry,Academia Sinica Changchun Institute of Applied Chemistry Academia Sinica

By surface organic synthesis a Fe(Ⅲ)tetra-o-aminophenyl porphyrin modified electrodewas successfully prepared on glassy carbon electrode surface through *** preparativeconditions were investigated in *** cyclic voltammetry and semidifferential neo-polarogra-phy in an acidic aqueous solution the behavior of the catalytic reduction ofoxygen on iron porphyriamodified electrode was *** on experimental results it was shown that the irreversibleprocess of 2-electron-reduction to hydrogen peroxide belongs to EC parallel catalytic process.

关键词： TAPP Researches on chemically modified electrode V.Catalytic reduction of oxygen on iron porphyrin modified electrode

Mirizzi syndrome:Problems and strategies

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 234-240页

作者： jun Wu Shuang-Yong Cai xu-Liang Chen Zhi-Tao Chen shao-Hua Shi Department of Hepatobiliary and Pancreatic Surgery People’s Hospital of Jiulongpo DistrictChongqing 400050China Department of Hepatobiliary and Pancreatic Surgery Shulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren University Shulan International Medical CollegeHangzhou 310003China

Mirizzi syndrome is a serious complication of gallstone *** is caused by the impacted stones in the gallbladder neck or cystic *** of the features of Mirizzi syndrome is severe inflammation or dense fibrosis at the Calot’s *** our clinical practice,bile duct,branches of right hepatic artery and right portal vein clinging to gallbladder infundibulum are often observed due to gallbladder infundibulum adhered to right hepatic *** intraoperative damage of branches of right hepatic artery occurs more easily than that of bile duct,all of which are hidden pitfalls for *** resonance cholangiopancreatography(MRCP)and endoscopic retrograde cholangiopancreatography(ERCP)are the preferable tools for the diagnosis of Mirizzi *** cholecystectomy in Mirizzi syndrome is easy to damage branches of right hepatic artery and bile duct due to gallbladder infundibulum adhered to right hepatic *** cholecystectomy is an easy,safe and definitive approach to Mirizzi *** combined with the application of ERCP,a laparoscopic management of Mirizzi syndrome by well-trained surgeons is feasible and *** objective of this review was to highlight its existing problems:(1)low preoperative diagnostic rate,(2)easy to damage bile duct and branches of right hepatic artery,and(3)high concomitant gallbladder ***,the review aimed to discuss the possible therapeutic strategies:(1)to enhance its preoperative recognition by imaging findings,and(2)to avoid potential pitfalls during surgery.

关键词： Mirizzi syndrome Bile duct injury Artery injury Surgical treatment Subtotal cholecystectomy

Transition-metal free trifluoromethylimination of alkenes enabled by direct activation of N-unprotected ketimines

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Chinese Chemical Letters 2024年第9期35卷 155-159页

作者： Boqiang Wang Yongzhuo xu Jiajia Wang Muyang Yang Guo-jun Deng Wen shao Key Laboratory for Green Organic Synthesis and Application of Hunan Province Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of EducationCollege of ChemistryXiangtan UniversityXiangtan 411105China Department School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

A highly site-selective intermolecular trifluoromethylimination of activated and unactivated olefins was reported under transition-metal-and photosensitizer-free *** newly developed strategy provides straightforward and efficient access to diverse value-added vicinal trifluoromethyl amines without resorting to the pre-functionalized *** experiments demonstrate that the approach proceeded through CF_(3)and iminyl two-radicals process,which were generated directly from commercially available benzophenone imine in a novel electron-donor mode via a SET process activated by the bifunctional hypervalent iodine *** synthetic potential of the protocols was further showcased via the condensation/amination sequential cascade,and transformations to accessβ-CF_(3)primary amines.

关键词： Transition-metal free Alkenes difunctionalization Amination Trifluoromethylation Single-electron transfer

A hybrid WUDT-NAFnet for simultaneous source data deblending

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Petroleum Science 2024年第3期21卷 1649-1659页

作者： Chao-Fan Ke shao-Huan Zu jun-Xing Cao xu-Dong Jiang Chao Li Xing-Ye Liu Key Laboratory of Earth Exploration and Information Technology of Ministry of Education Chengdu University of Technology State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology College of Geophysics Chengdu University of Technology

Simultaneous source technology,which reduces seismic survey time and improves the quality of seismic data by firing more than one source with a narrow time interval,is compromised by the massive blended ***,deblending algorithms have been developed to separate this ***,deep learning(DL)has been proved its great potential in suppressing the *** most popular DL method employs neural network as a filter to attenuate the blended noise in an iterative estimation and subtraction framework(IESF).However,there are still amplitude distortion and blended noise residual problems,especially when dealing with weak signal submerged in strong *** address these problems,we propose a hybrid WUDT-NAFnet,which contains two *** first network is a wavelet based U-shape deblending transformer network(WUDTnet),incorporated into IESF as a robust regularization term to iteratively separate the blended *** second network is a nonlinear activate free network(NAFnet)designed to recover the event amplitude and further suppress the weak noise residual in *** the hybrid network,the blended noise can be separated purposefully and *** using synthetic and field seismic data demonstrate that the WUDTNAFnet outperforms traditional curvelet transform(CT)based method and the deblending transformer(DT)model in terms of ***,for field applications,the data augmentation method of bicubic interpolation is applied to mitigate the feature difference between synthetic and field ***,the trained network exhibits strong signal preservation ability in numerical field example without requiring additional training.

关键词： Simultaneous-source Deblending Deep learning Transformer

Correlation analysis of interstitial maturity and prognosis of colorectal cancer:Meta-analysis

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2816-2825页

作者： Zhen-jun Liu xu-Wen Zhang Qi-Qi Liu shao-Zhao Wang Department of Gastrointestinal Surgery Feicheng People's HospitalFeicheng 271600Shandong ProvinceChina Department of Hepatobiliary Surgery Feicheng People's HospitalFeicheng 271600Shandong ProvinceChina Department of Gastrointestinal Surgery Peking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina Department of Anorectal Word Central Hospital Affiliated Shandong First Medical UniversityJinan 250013Shandong ProvinceChina

BACKGROUND To investigate the relationship between interstitial maturity and prognosis of colorectal *** To examine the correlation between interstitial maturity and the prognosis of colorectal *** The paper database PubMed,EMBASE,Cochranelibrary,Springerlink,CNKI,and Wanfang database were searched until December 2023."tumor stroma maturity""desmoplastic stroma reaction""desmoplastic reaction""stroma reaction""degree of stroma reaction""stroma classification""stroma density""colorectal cancer""colon cancer""rectal cancer""prognosis"were searched for the search *** system assessors independently screened the literature quality according to the inclusion exclusion criteria,Quality evaluation and data extraction were performed for the included literatures,and meta-analysis was performed for randomized control trials included at using Review Manager 5.2 *** Finally,data of 9849 patients with colorectal cancer from 19 cosets in 15 literatures were included,including 4339 patients with mature type(control group),3048 patients with intermediate type(intermediate group)and 2456 patients with immature type(immature group).The results of meta-analysis showed:Relapse-free survival[hazard ratio(HR)=2.66,95%confidence interval(CI):2.30-3.08;P<0.00001],disease-free survival(HR=3.68,95%CI:2.33-5.81;P<0.00001)and overall survival(HR=1.70,95%CI:1.53-1.87;P<0.00001)were significantly lower than those in mature group(control group);relapse-free survival(HR=1.36,95%CI:1.17-1.59;P<0.0001)and disease-free survival rate(HR=1.85,95%CI:1.53-2.24;P<0.0001)was significantly lower than the mature group(control group).CONCLUSION There is the correlation between tumor interstitial maturity and survival prognosis of colorectal cancer,and different degrees of tumor interstitial maturity have a certain impact on the quality of life of colorectal cancer patients.

关键词： Colorectal tumor Survival prognosis Tumor interstitial maturity Systematic review Meta-analysis

Coupling effect on the thermal hazard assessment of hazardous chemical materials via calorimetric technologies and simulation approaches

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Defence Technology（防务技术） 2024年第2期32卷 644-654页

作者： Yabei xu Jiankun shao Wei Wang Shengliang xu Dongping Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Science and Technology on Aerospace Chemical Power Laboratory Hubei Institute of Aerospace ChemotechnologyXiangyang 441003China

The coupling effect of heat absorption and release exists in the thermal decomposition of a few chemical ***,the impact of the above coupling on thermal hazard assessment is not considered in the literature *** this work,nitroguanidine(NQ)and 1,3,5-trinitro-1,3,5-triazine(RDX)are selected as representative materials to explore the influence of the coupling effect on the thermal hazard assessment of chemical *** linear heating experiments of NQ and RDX are carried out by a microcalorimeter and synchronous thermal *** thermal decomposition curves are decoupled by advanced thermokinetics *** thermal decomposition and kinetic parameters before and after decoupling are *** results of TG experiment show that both NQ and RDX began to lose mass during the endothermic *** endothermic melting and exothermic decomposition of NQ and RDX are coupled within this *** coupling effect has different degrees of influence on its initial decomposition temperature and safety *** with the parameters in the coupling state,the initial decomposition temperature and adiabatic induction period after decoupling *** self-accelerating decomposition temperature increases,and internal thermal runaway time *** the thermal hazard assessment of chemical materials with coupling effects,the calculated parameters after decoupling should be taken as an important safety index。

关键词： Calorimetric technologies Kinetics Thermal hazard Phase transformation Thermal decomposition

A compact route for efficient production of high-purity β-Ga_(2)O_(3) powder

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Rare Metals 2024年第9期43卷 4573-4584页

作者： Xiao-Wei Zhou Gao-Jie Chen Liang xu Zhi-jun shao Cheng Yang Yong-Pan Tian Zhuo Zhao School of Metallurgical Engineering Anhui University of TechnologyMa'anshan 243032China Low-Carbon Research Institute Anhui University of TechnologyMa'anshan 243032China

The present study has proposed a compact process for the production of high-purity β-Ga_(2)O_(3)powder by simply using gallium metal and water as the raw *** process basically consists of two essential steps including hydrothermal synthesis of Ga OOH and calcination of Ga OOH for the production of the target product of β-Ga_(2)O_(3).Thermodynamic evaluation and systematic experiments were conducted for process parameter optimization.X-ray diffractometer(XRD),scanning electron microscopy(SEM),thermogravimetryDdifferential scanning calorimetry(TG-DSC)and X-ray photoelectron spectroscopy(XPS)were utilized to clarify the reaction mechanisms of the hydrothermal synthesis and transformation of Ga OOH to β-Ga_(2)O_(3)by *** analysis of the final product of β-Ga_(2)O_(3)obtained under the optimal conditions was carried out with inductively coupled plasma mass spectrometry(ICP-MS),and the results showed that the contents of the representative impurities such as Ni,Cu,In,Mn,Co,Zn and Cr are obviously lower than the requirement of 5N β-Ga_(2)O_(3)standard,exhibiting excellent application prospect of the proposed process to produce high-purity β-Ga_(2)O_(3).

关键词： β-Ga_(2)O_(3) Hydrothermal synthesis Calcination Purity Reaction mechanism

A GMM approach in coupling internal data and external summary information with heterogeneous data populations

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Science China Mathematics 2024年第5期67卷 1115-1132页

作者： jun shao Jinyi Wang Lei Wang Key Laboratory of Advanced Theory and Application in Statistics and Data Science(East China Normal University) Ministry of EducationShanghai 200062China School of Statistics East China Normal UniversityShanghai 200062China Department of Statistics University of Wisconsin-MadisonWI 53706USA School of Statistics and Data Science KLMDASRLEBPS and LPMCNankai UniversityTianjin 300071China

Because of advances in data collection and storage,statistical analysis in modern scientific research and practice now has opportunities to utilize external information such as summary statistics from similar studies.A likelihood approach based on a parametric model assumption has been developed in the literature to utilize external summary information when the populations for external and main internal data are assumed to be the *** this article,we instead consider the generalized estimation equation(GEE)approach for statistical inference,which is semiparametric or nonparametric,and show how to utilize external summary information even when internal and external data populations are not the *** approach is coupling the internal data and external summary information to form additional estimation equations and then applying the generalized method of moments(GMM).We show that the proposed GMM estimator is asymptotically normal and,under some conditions,is more efficient than the GEE estimator without using external summary *** of the asymptotic covariance matrix of the GMM estimators are also *** results are obtained to confirm our theory and quantify the improvements by utilizing external *** example is also included for illustration.

关键词： adjustment for heterogeneity constraint data integration generalized method of moments summarystatistic