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Simple and efficient method for synthesis of metallodeutero-porphyrin derivatives bearing symmetrical disulphide bond

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Chinese Chemical Letters 2011年第5期22卷 527-530页

作者： Cheng Guo Sun Bing Cheng Hu Wei You Zhou shi Chao xu quan Zhi Deng Zu Liang Liu School of Chemical Engineering Nanjing University of Science and Technology Nanjing 210094 China

A novel thiol-derivative porphyrin[2,7,12,18-tetramethyl-13,17-di（3-disulfidepropyl）porphyrin]bearing the symmetrical disulphide bond and its metal complexes have been successfully prepared by means of modification ... 详细信息

关键词： Deuteroporphyrin Disulphide bond Synthesis

Process metallurgy and data-driven prediction and feedback of blast furnace heat indicators

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1228-1240页

作者： quan shi Jue Tang Mansheng Chu School of Metallurgy Northeastern UniversityShenyang 110819China Institute for Frontier Technologies of Low-carbon Steelmaking Northeastern UniversityShenyang 110819China Engineering Research Center of Frontier Technologies for Low-carbon Steelmaking(Ministry of Education) Shenyang 110819China

The prediction and control of furnace heat indicators are of great importance for improving the heat levels and conditions of the complex and difficult-to-operate hour-class delay blast furnace(BF)*** this work,a prediction and feedback model of furnace heat indicators based on the fusion of data-driven and BF ironmaking processes was *** data on raw and fuel materials,process op-eration,smelting state,and slag and iron discharge during the whole BF process comprised 171 variables with 9223 groups of data and were comprehensively analyzed.A novel method for the delay analysis of furnace heat indicators was *** extracted delay variables were found to play an important role in *** method that combined the genetic algorithm and stacking efficiently im-proved performance compared with the traditional machine learning algorithm in improving the hit ratio of the furnace heat prediction *** hit ratio for predicting the temperature of hot metal in the error range of±10℃ was 92.4%,and that for the chemical heat of hot metal in the error range of±0.1wt%was 93.3%.On the basis of the furnace heat prediction model and expert experience,a feedback model of furnace heat operation was established to obtain quantitative operation suggestions for stabilizing BF heat *** sugges-tions were highly accepted by BF ***,the comprehensive and dynamic model proposed in this work was successfully ap-plied in a practical BF *** improved the BF temperature level remarkably,increasing the furnace temperature stability rate from 54.9%to 84.9%.This improvement achieved considerable economic benefits.

关键词： blast furnace furnace heat genetic algorithm stacking prediction and feedback

Potential transformation of organic matter by microbes in cryoconite,Tibetan Plateau

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Science China Earth Sciences 2024年第6期67卷 1978-1989页

作者： Bixi GUO Yongqin LIU Kevin xu ZHONG quan shi Chen HE Qiang ZHENG Ruanhong CAI State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Center for the Pan-Third Pole Environment Lanzhou UniversityLanzhou 730000China Department of Earth Oceanand Atmospheric SciencesUniversity of British ColumbiaVancouverBC V6T 1Z4Canada State Key Laboratory of Heavy Oil Processing Petroleum Molecules Engineering Center(PMEC)China University of PetroleumBeijing 102249China State Key Laboratory for Marine Environmental Science Collage of Ocean and Earth SciencesXiamen UniversityXiamen 361102China Fujian Key Laboratory of Marine Carbon Sequestration Xiamen UniversityXiamen 361005China

Microorganisms play an essential role in the glacier carbon cycle;how they transform organic matter in mountain glacial cryoconite remains to be ***,we applied ultra-high resolution Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)and deep sequencing of 16S rRNA gene,to investigate the temporal microbial transformation of dissolved organic matter(DOM)of the Tibetan Plateau *** the 60-day incubation,we found that DOM in cryoconite underwent a three-stage transformation,with decreasing bioavailability over *** microbial community did not change much in the first week while degrading DOM molecules that were associated with higher H/C_(wa)and lower O/C_(wa).During days 15-30,DOM composition remained stable while microbial diversity *** day 60,the DOM was microbially converted into a higher state of recalcitrance,with higher values of aromatic index,O/C_(wa),and lower H/C_(wa),which contained molecules containing more *** among various microbial taxa,like Cyanobacteria,Bacteroidota,Gammaproteobacteria,Firmicutes,and Actinobacteriota,drove the DOM transformation in *** study sheds light on the in-situ transformation of DOM composition meditated by microbial populations in cryoconite at a temporal scale,providing new insights into understanding the microbial roles in the glacier organic carbon transformation.

关键词： Cryoconite Dissolved organic matter Biodegradation Microbial community Temporal variation

A survey on facial image deblurring

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Computational Visual Media 2024年第1期10卷 3-25页

作者： Bingnan Wang Fanjiang xu quan Zheng Institute of Software Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

When a facial image is blurred,it significantly affects high-level vision tasks such as face *** purpose of facial image deblurring is to recover a clear image from a blurry input image,which can improve the recognition accuracy,***,general deblurring methods do not perform well on facial ***,some face deblurring methods have been proposed to improve performance by adding semantic or structural information as specific priors according to the characteristics of the facial *** this paper,we survey and summarize recently published methods for facial image deblurring,most of which are based on deep ***,we provide a brief introduction to the modeling of image ***,we summarize face deblurring methods into two categories:model-based methods and deep learning-based ***,we summarize the datasets,loss functions,and performance evaluation metrics commonly used in the neural network training *** show the performance of classical methods on these datasets and metrics and provide a brief discussion on the differences between model-based and learning-based ***,we discuss the current challenges and possible future research directions.

关键词： facial image deblurring model-based deep learning-based semantic or structural prior

Giant bile duct dilatation in newborn:A case report

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World Journal of Clinical Cases 2024年第6期12卷 1150-1156页

作者： Dong-Wen quan Peng-Gang Li Xiang-Hua xu shi-Qi Liu The Second Clinical Medical School Shaanxi University of Chinese MedicineXianyang 712000Shaanxi ProvinceChina The First School of Clinical Medicine Shaanxi University of Chinese MedicineXianyang 712000Shaanxi ProvinceChina Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Department of Neonatal Surgery Xi’an Children’s Hospital Affiliated Xi’an Jiaotong UniversityXi’an 710003Shaanxi ProvinceChina

BACKGROUND Giant congenital biliary dilation(CBD)is a rare condition observed in clinical *** born with this condition often experience a poor overall health status,and the disease progresses rapidly,leading to severe biliary obstruction,infections,pressure exerted by the enlarged CBD on abdominal organs,disturbances in the internal environment,and multiple organ *** treatment of giant CBD using laparoscopy is challenging due to the high degree of variation in the shape of the bile duct and other organs,making it difficult to separate the bile duct wall from adjacent tissues or to control *** SUMMARY Herein,we present the details of an 11-d-old male newborn who was diagnosed with giant *** patient was admitted to the neonatal surgery department of our hospital due to a history of common bile duct cyst that was detected more than 3 mo ago,and also because the patient had been experiencing yellowish skin for the past 9 *** abnormal echo in the fetal abdomen was first noticed by the patient’s mother during a routine ultrasound examination at a local hospital,when the patient was at 24 wk+6 d of *** finding raised concerns about the possibility of congenital biliary dilatation(22 mm×21 mm).Subsequent ultrasound examinations at different hospitals consistently confirmed the presence of a congenital biliary *** specific treatment was administered for biliary dilatation during this period.A computed tomography scan conducted during the hospitalization revealed a large cystic mass in the right upper quadrant and pelvis,measuring approximately 9.2 cm×7.4 cm×11.3 *** on the CONCLUSION The analysis reveals that prenatal imaging techniques,such as ultrasound and magnetic resonance imaging,play a crucial role in the early diagnosis,fetal prognosis,and treatment plan for giant *** surgery for giant CBD presents certain challenges,including difficulties in separating the cyst wall,anastomosis,and hemos

关键词： Acute cholangitis Congenital biliary dilation Laparoscopic surgery vs Open hepatic duct-jejunostomy Case report

In Vitro Reassembly of Tobacco Ribulose-1,5-bisphosphate Carboxylase/Oxygenase from Fully Denatured Subunits

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Acta Biochimica et Biophysica Sinica 2006年第10期38卷 737-745页

作者： Zhen-Hua YONG Gen-Yun CHEN* Jiao-Nai shi Da-quan xu Institute of Plant Physiology and Ecology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,and Graduate School of the Chinese Academy of Sciences,Shanghai 200032,China Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences and Graduate School of the Chinese Academy of SciencesShanghai 200032 China

It has been generally proved impossible to reassemble ribulose-1,5-bisphosphate carboxylase/oxygenase （Rubisco） from fully denatured subunits in vitro in higher plant,because large subunit of fullydenatured Rubisco is liable to precipitate when the denaturant is removed by common methods of directdilution and one-step *** our experiment,the problem of precipitation was resolved by an improvedgradual dialysis method,which gradually decreased the concentration of ***,fully denaturedRubisco subunits still could not be reassembled into holoenzyme using gradual dialysis unless chaperonin 60was *** restored activity of reassembled Rubisco was approximately 8% of natural *** of reassembled Rubisco increased greatly when heat shock protein 70 was present in the *** and Mg2+ were unnecessary for in vitro reassembly of Rubisco,and Mg2+ inhibited the *** reassembly was weakened when ATP,Mg2+ and K+ existed together in the reassembly process.

关键词： Rubisco reassembly gradual dialysis chaperonin 60 Hsp70

Linear Viscoelasticity of ABA-type Vitrimer Based on Dioxaborolane Metathesis

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Chinese Journal of Polymer Science 2024年第10期42卷 1495-1504,I0010页

作者： shi-Long Wu Huan-Huan Yang quan Chen State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of ScienceChangchun130022China University of Science and Technology of China Hefei230026China

In this study,we synthesized a series of ABA-type vitrimers by crosslinking the short A moieties of precursors with a bifunctional crosslinker and evaporating the small molecular *** vitrimer samples thus prepared exhibit linear viscoelasticity dependent on the length of A moiety as well as the content of the *** the average number of A monomers per end moiety m=1.1,the crosslinker can only extend the chain but not crosslink the *** m becomes 2.8 or higher,introducing a crosslinker first leads to the gelation,whereas excess in crosslinker molecules leads opening of the crosslinking sites and accordingly reentry into the sol ***,a further increase in the length of the A moieties increases the relaxation time much weaker than the exponential increase seen for the physically crosslinked ABAtype *** attribute this difference to the distinct relaxation mechanisms:the relaxation of the vitrimer samples is based on relatively independent exchange reactions,which contrasts with the ABA-type ionomers that relax through the collective hopping of connected ionic groups from one ion aggregate to another.

关键词： Polymer rheology Linear viscoelasticity ABA-type vitrimer Relaxation mechanism Kinetics and thermodynamics

Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

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Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： shi-Liang xu Ying-Nan Zhao Yao Yu Qi Yang Li-Hua Na Heng Liu Chun-Yu Zhang xue-quan Zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in *** catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of ***,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene *** characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer *** resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity

Mechanism analysis of foam penetration in EPB shield tunnelling with a focus on FER and soil particle size

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Underground Space 2024年第4期17卷 170-187页

作者： He Huang quan Sun Tao xu Wanhuan Zhou State Key Laboratory of Internet of Things for Smart City and Department of Civil and Environmental Engineering University of MacaoMacao 999078China Department of Civil and Environmental Engineering University of MacaoMacao 999078China School of Transportation Southeast UniversityNanjing 210000China

Parameters of foam penetration in earth pressure balance(EPB)shield tunnelling,such as permeability coefficients and penetration distances,significantly impact tunnel face ***,existing studies have faced inaccuracies in analysing these parameters due to imitations in experimental *** study addresses this issue by employing enhanced methods for a more precise analysis of foam *** involving three distinct sand types(coarse,medium,and fine)and three foam expansion ratios(FER)(10,15,and 20)are conducted using a modified model test *** from a novel computer vision-based method,the model test outcomes unveil two distinct foam penetration paths:liquid migration(L_(w))and bubble migration(L_(f)).Three penetration phases-namely,injection,blockage&drainage,and breakage—are identified based on L_(w)and L_(f)*** initial"injection"phase conforms to Darcy’s law and is amenable to mathematical *** foam with FER of 15 has the maximum viscosity and,hence the L_(f)and permeability in the penetration tests with FER of 15 are the lowest in the same *** bubble size distribution of foam with different FER shows minor ***,the characteristics of foam penetration vary due to the distinct particle size distribution(PSD)of different *** penetration creates low-permeability layers in both medium and fine sands due to the larger bubble size of the foam compared to the estimated pore sizes of medium and fine *** the coarse sand results in a different situation due to its large pore *** distinctive characteristics of foam penetration in different sand strata are notably shaped by FER,PSD,and pore size *** insights shed light on the complex interactions during foam penetration at the tunnel face,contributing valuable knowledge to EPB shield tunnelling practices.

关键词： EPB Soil conditioning Foam penetration Permeability Tunnel face