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Extraction kinetics of phenol with N, N-di (1-methyl-heptyl)acetamide-kerosene using hollow fiber membrane extractor

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Journal of Environmental Sciences 2001年第3期13卷 380-384页

作者： YANG Zhu xian, DU hui fang, sun xian bo, XIA Ye, ZHOU Zu ming(Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China. Department of Environmental Science and Engineering Fudan University Shanghai 200433 China.

Extraction kinetics of phenol with N,N-di(1-methyl-heptyl) acetamide-kerosene using hollow fiber membrane extractor has been studied. The rate regularities and kinetic types of forward and backward extraction were obtained respectively by determining the forward and backward extraction rate under various experimental conditions. The mass transfer mechanism was discussed. Both the forward and backward extraction of phenol might be controlled by diffusion processes, and the diffusion resistance for both forward and backward extraction mainly exists in aqueous phase. In addition, ways to optimize the extraction process of phenol were discussed as well.

关键词： extraction kinetics phenol hollow fiber membrane extractor

A sign-function receiving scheme for sine signals enhanced by stochastic resonance

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Chinese Physics B 2021年第8期30卷 240-247页

作者： Zhao-Rui Li Bo-Hang Chen hui-xian sun Guang-Kai Liu Shi-Lei Zhu Department of Electronics and Optical Engineering Army Engineering UniversityShijiazhuang 050003China Beijing Institute of Tracking and Telecommunications Technology Beijing 100094China

To address the problem that it is difficult to detect an intermediate frequency(IF)signal at the receiving end of a communication system under extremely low signal-to-noise ratio(SNR)conditions,we propose a stochastic resonance(SR)-enhanced sine-signal detection method based on the sign *** analyzing the SR mechanism of the sine signal and combining it with the characteristics of a dual-sequence frequency-hopping(DSFH)receiver,a periodic stationary solution of the Fokker-Planck equation(FPE)with a time parameter is *** extreme point of the sine signal is selected as the decision time,and the force law of the electromagnetic particles is analyzed.A receiving structure based on the sign function is proposed to maximize the output difference of the system,and the value condition of the sign function is *** order to further improve the detection performance,in combination with the central-limit theorem,the sampling points are averaged N times,and the signal-detection problem is transformed into a hypothesis-testing problem under a Gaussian *** theoretical analysis and simulation experiment results confirm that when N is 100 and the SNR is greater than 20 dB,the bit-error ratio(BER)is less than 1.5×10^(-2) under conditions in which the signal conforms to the optimal SR parameters.

关键词： stochastic resonance Fokker-Planck equation sine signal detection sign-function receiving structure

Study on the off situ reconstruction of the core neutron field based on dual-task hybrid network architecture

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Nuclear Science and Techniques 2025年第1期36卷 175-191页

作者： Pei Cao hui Ding Cheng-Long Cao Zi-hui Yang Guo-Min sun School of Artificial Intelligence and Big Data Hefei UniversityHefei 230001China College of Electronic Engineering National University of Defense TechnologyHefei 230001China Institute of Nuclear Energy Safety Technology HFIPSChinese Academy of SciencesHefei 230027China

The off situ accurate reconstruction of the core neutron field is an important step in realizing real-time reactor *** existing off situ reconstruction method of the neutron field is only applicable to cases wherein a single region changes at a specified location of the ***,when the neutron field changes are complex,the accurate identification of the individual changed regions becomes challenging,which seriously affects the accuracy and stability of the neutron field ***,this study proposed a dual-task hybrid network architecture(DTHNet)for off situ reconstruction of the core neutron field,which trained the outermost assembly reconstruction task and the core reconstruction task jointly such that the former could assist the latter in the reconstruction of the core neutron field under core complex ***,to exploit the characteristics of the ex-core detection signals,this study designed a global-local feature upsampling module that efficiently distributed the ex-core detection signals to each reconstruction unit to improve the accuracy and stability of *** experiments were performed on the simulation datasets of the CLEAR-I reactor to verify the accuracy and stability of the proposed *** results showed that when the location uncertainty of a single region did not exceed nine and the number of multiple changed regions did not exceed ***,the reconstructed ARD was within 2%,RD_(max)was maintained within 17.5%,and the number of RD≥10%was maintained within ***,when the noise interference of the ex-core detection signals was within±2%,although the average number of RD≥10%increased to 16,the average ARD was still within in 2%,and the average RD_(max)was within 22%.Collectively,these results show that,theoretically,the DTHNet can accurately and stably reconstruct most of the neutron field under certain complex core changes.

关键词： Real-time reactor monitoring Core neutron field reconstruction Dual-task hybrid network architecture Global-local feature upsampling module

Sequence-controlled dynamic covalent units enable decoupling of mechanical and self-healing performance of polymers

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Science China Chemistry 2025年第2期68卷 745-753页

作者： Luzhi Zhang Hongfei Huang Lijie sun Xiaopeng Ma hui Tan Zhengwei You Respiratory Department Shenzhen Children’s Hospital Affiliated to Shantou University Medical CollegeShenzhen 518038China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringInstitute of Functional MaterialsResearch Base of Textile Materials for Flexible Electronics and Biomedical Applications(China Textile Engineering Society)Shanghai Key Laboratory of Lightweight CompositeShanghai Engineering Research Center of Nano-Biomaterials and Regenerative MedicineDonghua UniversityShanghai 201620China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China

Sequence regulation provides an effective approach to controlling the properties of polymer ***,this approach remains an open question in the field of dynamic polymers,which emerge as more and more important new generation ***,we systematically investigate the effect of sequence control of dynamic covalent units in tuning the properties of *** sequence-controlled poly(oxime-urethanes)are *** dynamic oxime-urethane groups are relatively dispersed(SCP-1)or concentrated(SCP-2)distributed in their molecular *** sequence control strategy provides an efficient way to decouple the mechanical and self-healing performance of polymers,which is one of the most pressing challenges in the *** relatively dispersed oxime-urethane groups in SCP-1 not only facilitate the reorganization of the dynamic covalent bonds but also increase the probability of the reformation of hydrogen *** reversible dissociation/reassociation of dynamic bonds is conducive to dissipating energy to enhance mechanical performance and promote self-healing *** a result,SCP-1 exhibits much faster self-healing than SCP-2,and its tensile strength is nearly twice that of *** addition,energy dissipation capacity and degradation behavior also show significant sequence ***,this work reveals a new molecular structure-property relationship and provides a powerful strategy to construct high-performance polymers.

关键词： sequence control dynamic polymer poly(oxime-urethane) strength polyurethane

New classification of gastric polyps:An in-depth analysis and critical evaluation

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World Journal of Gastroenterology 2025年第7期31卷 149-155页

作者： Xiao-hui Liao Ying-Ming sun Hong-Bin Chen Department of Gastroenterology The First Hospital of Sanming Affiliated to Fujian Medical UniversityFujian Medical UniversitySanming 365000Fujian ProvinceChina Department of Medical and Radiation Oncology Sanming First HospitalFujian Medical UniversitySanming 365000Fujian ProvinceChina Department of Gastroenterology I Sanming First HospitalFujian Medical UniversitySanming 365000Fujian ProvinceChina

With the widespread use of upper gastrointestinal endoscopy,more and more gastric polyps(GPs)are being *** management strategies often rely on histopathologic examination,which can be time-consuming and may not guide immediate clinical *** paper aims to introduce a novel classification system for GPs based on their potential risk of malignant transformation,categorizing them as"good","bad",and"ugly".A review of the literature and clinical case analysis were conducted to explore the clinical implications,management strategies,and the system's application in endoscopic *** polyps,mainly including fundic gland polyps and inflammatory fibrous polyps,have a low risk of malignancy and typically require minimal or no *** polyps,mainly including hyperplastic polyps and adenomas,pose an intermediate risk of malignancy,necessitating closer monitoring or *** polyps,mainly including type 3 neuroendocrine tumors and early gastric cancer,indicate a high potential for malignancy and require urgent and comprehensive *** new classification system provides a simplified and practical framework for diagnosing and managing GPs,improving diagnostic accuracy,guiding individualized treatment,and promoting advancements in endoscopic *** some challenges,such as the risk of misclassification due to similar endoscopic appearances,this system is essential for the standardized management of *** also lays the foundation for future research into biomarkers and the development of personalized medicine.

关键词： Gastric polyps Classification Fundic gland polyps Inflammatory fibroid polyps Hyperplastic polyps Adenomas Neuroendocrine tumors Early gastric cancer Patient management

Evolution and generation mechanism of retained oil in lacustrine shales: A combined ReaxFF-MD and pyrolysis simulation perspective

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Petroleum Science 2025年第1期22卷 29-41页

作者： Biao sun Xiao-Ping Liu Jie Liu Tian Liu Zu-xian Hua Wen-Di Peng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) College of Geosciences China University of Petroleum (Beijing) International Petroleum Exploration and Production Corporation SINOPEC

To accurately investigate the evolution characteristics and generation mechanism of retained oil, the study analyzed organic-rich lacustrine shale samples from the Paleogene Kongdian Formation in Cangdong Sag, Bohai Bay Basin. This analysis involves Rock-Eval pyrolysis, pyrolysis simulation experiments,Gas Chromatograph Mass Spectrometer（GC-MS）, and reactive molecular dynamics simulations（Reax FF）. The results revealed the retained oil primarily consisted of n-alkanes with carbon numbers ranging from C14to C36. The generation of retained oil occurred through three stages. A slow growth stage of production rate was observed before reaching the peak of oil production in Stage I. Stage II involved a rapid increase in oil retention, with C12-C17and C24-C32serving as the primary components,increasing continuously during the pyrolysis process. The generation process involved the cleavage of weak bonds, including bridging bonds（hydroxyl, oxy, peroxy, imino, amino, and nitro）, ether bonds, and acid amides in the first stage（Ro= 0.50%-0.75%）. The carbon chains in aromatic ring structures with heteroatomic functional groups breaks in the second stage（Ro= 0.75%-1.20%）. In the third stage（Ro= 1.20%-2.50%）, the ring structures underwent ring-opening reactions to synthesize iso-short-chain olefins and radicals, while further breakdown of aliphatic chains occurred. By coupling pyrolysis simulation experiments and molecular simulation technology, the evolution characteristics and bond breaking mechanism of retained oil in three stages were revealed, providing a reference for the formation and evolution mechanism of retained oil.

关键词： Lacustrine shale Retained oiliness evolution Pyrolysis simulation experiments ReaxFF molecular dynamics Hydrocarbon generation evolution

Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw

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Green Energy & Environment 2025年第1期10卷 161-172页

作者： Meng-Ying Liu Zhe-hui Zhang Xue-Qi Wang Qian sun Chen Zhang Yu Li Zhuohua sun Katalin Barta Feng Peng Tong-Qi Yuan State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing100083China Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing100083China Department of Chemistry Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28/II8010 GrazAustria

Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent ***,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps *** key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene *** utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling *** the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.

关键词： Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural

Design of multifunctional interfaces on ceramic solid electrolytes for high-performance lithium-air batteries

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Green Energy & Environment 2025年第1期10卷 183-192页

作者： Yunxin Shi Ziyang Guo Changhong Wang Mingze Gao Xiaoting Lin hui Duan Yonggang Wang Xueliang sun College of Energy Material and Chemistry College of Chemistry and Chemical EngineeringInner Mongolia UniversityHohhot010021China Department of Mechanical and Materials Engineering Western UniversityLondonONN6A 5B9Canada Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New EnergyiChEM(Collaborative Innovation Center of Chemistry for Energy Materials)Fudan UniversityShanghai200433China Eastern Institute for Advanced Study Eastern Institute of TechnologyNingboZhejiang315100China

High-energy-density lithium(Li)–air cells have been considered a promising energy-storage system,but the liquid electrolyte-related safety and side-reaction problems seriously hinder their *** address these above issues,solid-state Li–air batteries have been widely ***,many commonly-used solid electrolytes generally face huge interface impedance inLi–air cells and also showpoor stability towards ambient air/Li ***,we fabricate a differentiating surface-regulated ceramic-based composite electrolyte(DSCCE)by constructing disparately LiI-containing polymethyl methacrylate(PMMA)coating and Poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)layer on both sides of Li_(1.5)Al_(0.5)Ge_(1.5)(PO_(4))_(3)(LAGP).The cathode-friendly LiI/PMMA layer displays excellent stability towards superoxide intermediates and also greatly reduces the decomposition voltage of discharge products in Li–air ***,the anode-friendly PVDF-HFP coating shows low-resistance properties towards ***,Li dendrite/passivation derived from liquid electrolyte-induced side reactions and air/I-attacking can be obviously suppressed by the uniformand compact composite *** a result,the DSCCE-based Li–air batteries possess high capacity/low voltage polarization(11,836mAh g^(-1)/1.45Vunder 500mAg^(-1)),good rate performance(capacity ratio under 1000mAg^(-1)/250mAg^(-1) is 68.2%)and longterm stable cell operation(~300 cycles at 750 mA g^(-1) with 750 mAh g^(-1))in ambient air.

关键词： Li-air batteries Li_(1.5)Al_(0.5)Ge_(1.5)(PO_(4))_(3) Polymers Composite electrolyte Ambient air

CMOS direct conversion X-ray detector coupled with fluorinated liquid

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Nuclear Science and Techniques 2025年第1期36卷 59-68页

作者： Shi-Hua Liu Chao-Song Gao Xin Zhang xiang-Ming sun Meng Wu Zhi-hui Han Tong Wan Yong-Shuai Ge Key Laboratory of Quark&Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China Guizhou Education University Guiyang 550018China Research Center for Medical Artificial Intelligence Chinese Academy of SciencesShenzhen Institutes of Advanced TechnologyShenzhen 518055China

X-ray detectors show potential applications in medical imaging,materials science,and nuclear *** achieve high detection efficiency and spatial resolution,many conventional semiconductor materials,such as amorphous selenium,cadmium telluride zinc,and perovskites,have been utilized in direct conversion X-ray ***,these semiconductor materials are susceptible to temperature-induced performance degradation,crystallization,delamination,uneven lattice growth,radiation damage,and high dark *** study explores a new approach by coupling an FC40 electronic fluorinated liquid with a specialized high-resolution and high-readout-speed complementary metal-oxide-semiconductor(CMOS)pixel array,specifically the Topmetal II−chip,to fabricate a direct conversion X-ray *** fluorinated liquid FC40(molecular formula:C_(21)F_(48)N_(2))is an electronic medium that is minimally affected by temperature and displays no issues with uniform *** exhibits a low dark current and minimal radiation damage and enables customizable thickness in X-ray *** addresses the limitations inherent in conventional semiconductor-based *** this study,simple X-ray detector imaging tests were conducted,demonstrating the excellent coupling capability between FC40 electronic fluorinated liquid and CMOS chips by the X-ray detector.A spatial resolution of 4.0 lp/mm was measured using a striped line par card,and a relatively clear image of a cockroach was displayed in the digital radiography imaging *** test results indicated the feasibility of fabricating an X-ray detector by combining FC40 electronic fluorinated liquid and CMOS *** to the absence of issues related to chip-material coupling,a high spatial resolution could be achieved by reducing the chip pixel *** method presents a new avenue for studies on novel liquid-based direct conversion X-ray detectors.

关键词： FC40 electronic fluorinated liquid CMOS pixel chip X-ray detector Spatial resolution