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Probing the interaction between asphaltene-wax and its effects on the crystallization behavior of waxes in heavy oil via molecular dynamics simulation

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Petroleum Science 2024年第4期21卷 2839-2848页

作者： yong Hu Xi Lu Hai-Bo Wang Ji-Chao Fang Yi-Ning wu jian Fang Sun SINOPEC Petroleum Exploration and Production Research Institute Shandong Key Laboratory of Oilfield Chemistry School of Petroleum Engineering China University of Petroleum (East China)

High content of asphaltenes and waxes leads to the high pour point and the poor flowability of heavy oil,which is adverse to its efficient development and its transportation in *** the interaction mechanism between asphaltene-wax is crucial to solve these problems,but it is still *** this paper,molecular dynamics simulation was used to investigate the interaction between asphaltenewax and its effects on the crystallization behavior of waxes in heavy *** show that molecules in pure wax are arranged in a paralleled *** wax molecules in heavy oil,which are close to the surface of asphaltene aggregates,are bent and arranged *** the mass fraction of asphaltenes in asphaltene-wax system(ωasp) is 0-25 wt%,the attraction among wax molecules decreases and the bend degree of wax molecules increases with the increase of ω*** ωaspincreases from 0 to 25 wt%,and the attraction between asphaltene-wax is stronger than that among *** causes that the wax precipitation point changes from 353 to 333 *** the ωaspincreases to 50 wt%,wax molecules are more dispersed owing to the steric hindrance of asphaltene aggregates,and the interaction among wax molecules transforms from attraction to *** causes that the ordered crystal structure of waxes can't be formed at normal ***,the asphaltene,with the higher molecular weight or the more hetero atoms,has more obvious inhibition to the formation of wax ***,resins also have an obvious inhibition on the wax crystal due to the formation of asphalteneresin aggregates with a larger *** results reveal the interaction mechanism between asphaltene-wax,and provide useful guidelines for the development of heavy oil.

关键词： Heavy oil Interaction mechanism Asphaltenes Waxes Molecular dynamics

Clinical characteristics of early and late drug-eluting stent in-stent restenosis and mid-term prognosis after repeated percutaneous coronary intervention

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Chinese Medical Journal 2020年第22期133卷 2674-2681页

作者： jian-Feng Zheng Ting-Ting Guo Yuan Tian yong Wang Xiao-Ying Hu Yue Chang Hong Qiu Ke-Fei Dou Yi-Da Tang Jin-Qing Yuan yong-jian wu Hong-Bing Yan Shu-Bin Qiao Bo Xu Yue-Jin Yang Run-Lin Gao Department of Cardiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China Department of Cardiology Urumqi Friendship HospitalUrumqiXinjiang 830049China

Background:The mechanism and characteristics of early and late drug-eluting stent in-stent restenosis(DES-ISR)have not been fully *** there are different outcomes among those patients being irrespective of their repeated treatments remain a knowledge ***:A total of 250 patients who underwent initial stent implantation in our hospital,and then were readmitted to receive treatment for the reason of recurrent significant DES-ISR in 2016 were *** patients were categorized as early ISR(<12 months;E-ISR;n=32)and late ISR(≥12 months;L-ISR;n=218).Associations between patient characteristics and clinical performance,as well as clinical outcomes after a repeated percutaneous coronary intervention(PCI)were *** composite endpoint of major adverse cardiac events(MACEs)included cardiac death,non-fatal myocardial infarction(MI),or target lesion revascularization(TLR).Results:Most baseline characteristics are similar in both groups,except for the period of ISR,initial pre-procedure thrombolysis in myocardial infarction,and some serum biochemical *** incidence of MACE(37.5%vs.5.5%;P<0.001)and TLR(37.5%vs.5.0%;P<0.001)is higher in the E-ISR *** multivariate analysis,E-ISR(odds ratio[OR],13.267;[95%CI 4.984-35.311];P<0.001)and left ventricular systolic dysfunction(odds ratio[OR],6.317;[95%CI 1.145-34.843];P=0.034)are the independent predictors for MACE among DES-ISR patients in the mid-term follow-up of 12 ***:Early ISR and left ventricular systolic dysfunction are associated with MACE during the mid-term follow-up period for DES-ISR *** results may benefit the risk stratification and secondary prevention for DES-ISR patients in clinical practice.

关键词： In-stent restenosis Neointimal hyperplasia Risk factors Drug-eluting stent

NaBH4-induced phase transition of CoSe_(2) with abundant Se deficiency for acidic oxygen reduction to hydrogen peroxide

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Rare Metals 2024年第2期43卷 500-510页

作者： Cai-Di Han yong-Chao Zhang Qian Zhang Jin-Ting wu jian Gao Ji-Jun Zou Xiao-Dong Zhu State Key Laboratory Base of Eco-Chemical Engineering College of Chemical Engineering Qingdao University of Science and TechnologyQingdao266042China Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China

Electrocatalytic oxygen reduction(ORR)via the 2e−pathway to form H_(2)O_(2) in acidic medium has attracted extensive ***,the low activity,insufficient selectivity and high cost of catalysts have been the ***,CoSe_(2) with abundant Se deficiency was synthesized by a simple hydrothermal method,and the addition of NaBH4-induced CoSe_(2) phase transition from orthorhombic to cubic phase with more Se *** cubic phase CoSe_(2) with abundant Se deficiency can effectively regulate the surface electronic structure with suitable binding energies of*OOH and*O,which shows high activity,selectivity and long-term stability for acidic ORR to H_(2)O_(2).The onset potential is as low as 0.73 V *** hydrogen electrode(RHE),the H_(2)O_(2) selectivity is 84%(0 V ***),and the average electron transfer number is about ***,the H_(2)O_(2) yield measured using a flow cell is as high as 115.92 mmol·gcat.^(−1)·h^(−1) and the Faradaic efficiency is 70%at 0 V ***,which presents high potential in electrocatalytic acidic ORR to H_(2)O_(2) and organic pollutant degradation using the electron-Fenton process.

关键词： Se defected CoSe_(2) Crystal phase transition Electrocatalysis Acidic oxygen reduction Hydrogen peroxide

Comparison of drug eluting stents with bare metal stents in daily practice for bifurcation lesions in Chinese patients

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Chinese Medical Journal 2006年第14期119卷 1157-1164页

作者： KANG Sheng YANG Yue-jin XU Bo CHEN Ji-lin QIAO Shu-bin YAO Min CHEN Jue wu yong-jian LIU Hai-bo DAI Jun YUAN Jin-qing LI jian-jun GAO Run-lin Department of Cardiology Cardiovascular Institute ＆ Fuwai Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100037 China

Background Recently, numerous randomized and controlled trials have demonstrated great advantages of drug eluting stents （DES） with respect to significant reduction of restenosis and recurrence of symptoms and improvement of clinical outcomes after percutaneous coronary intervention （PCI）. Little is known about the comparative effects between DES and bare metal stents （BMS） for bifurcation angioplasty in the Chinese population. We compared the inpatient and 7-month follow-up outcomes between DES and BMS for the treatment of bifurcation lesions. Methods From April 2004 to October 2005, 291 Chinese patients [85.9% male, mean age （57.8± 10.4） years] underwent DES （387 lesions） and/or BMS （297 lesions） implantation for bifurcation lesions. Clinical and angiographic follow-up was performed at 7 months. Results Compared with BMS group, patients in DES group had significantly lower rates of restenosis at main branch （9.5% vs 28.7%, P 〈 0.001） or side branch （14.5% vs 37.0%, P 〈 0.001） and major adverse cardiac events （MACE）（14.0% vs 26.3%, P = 0.000）. The occurrence rate of late in-stent thrombosis did not differ between the two groups in both main （0.8% vs 0, P = 0.224） and side branches （1.4% vs 0, P =0.198）. Target lesion revascularization （TLR） was less frequent in DES group for main branch （8.3% vs 21.3%, P 〈 0.001） and for side branch （7.6% vs 23.5%, P 〈 0.001）. Multivariate regression analysis revealed that total stent length （OR = 1.029, P = 0.01）, postprocedural in-stent minimum lumen diameter （OR = 0.476, P = 0.03） and stent type （OR = 3.988, P = 0.0001） were independent predictors of TLR for main branch. Prior history of coronary intervention （OR = 2.424, P =0.041）, angulated lesion （OR = 2.337, P = 0.033）, postdilation （OR = 0.267, P = 0.035） and stent type （DES vs BMS, OR = 5.459, P = 0.000） were independent predictors of TLR for side branch. Conclusion The implantation of DES may be associated with greater reduction of restenosis and TLR than BMS in bi

关键词： percutaneous coronary intervention drug eluting stent bare metal stent bifurcation

Development and validation of a nomogram model for predicting the risk of gallstone recurrence after gallbladder-preserving surgery

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 288-292页

作者： Peng Liu yong-Wei Chen Che Liu Yin-Tao wu Wen-Chao Zhao jian-yong Zhu Yang An Nian-Xin Xia Faculty of Hepato-Pancreato-Biliary Surgery the First Medical CenterChinese PLA General HospitalBeijing 100853China Institute of Hepatobiliary Surgery of Chinese PLA Beijing 100853China Key Laboratory of Digital Hepetobiliary Surgery of Chinese PLA Beijing 100853China

Background:The high incidence of gallstone recurrence was a major concern for laparoscopic gallbladderpreserving *** study aimed to investigate the risk factors for gallstone recurrence after gallbladder-preserving surgery and to establish an individualized nomogram model to predict the risk of gallstone ***:The clinicopathological and follow-up data of 183 patients who were initially diagnosed with gallstones and treated with gallbladder-preserving surgery at our hospital from January 2012 to January 2019 were retrospectively *** independent predictive factors for gallstone recurrence following gallbladder-preserving surgery were identified by multivariate logistic regression analysis.A nomogram model for the prediction of gallstone recurrence was constructed based on the selected *** C-index,receiver operating characteristic(ROC)curve and calibration curve were used to evaluate the predictive power of the nomogram model for gallstone ***:During the follow-up period,a total of 65 patients experienced gallstone recurrence,and the recurrence rate was 35.5%.Multivariate logistic regression analysis revealed that the course of gallstones>2 years[odds ratio(OR)=2.567,95%confidence interval(CI):1.270-5.187,P=0.009],symptomatic gallstones(OR=2.589,95%CI:1.059-6.329,P=0.037),multiple gallstones(OR=2.436,95%CI:1.133-5.237,P=0.023),history of acute cholecystitis(OR=2.778,95%CI:1.178-6.549,P=0.020)and a greasy diet(OR=2.319,95%CI:1.186-4.535,P=0.014)were independent risk factors for gallstone recurrence after gallbladder-preserving surgery.A nomogram model for predicting the recurrence of gallstones was established based on the above five *** results showed that the C-index of the nomogram model was 0.692,suggesting it was valuable to predict gallstone ***,the calibration curve showed good consistency between the predicted probability and actual ***:The nomogram model for

关键词： Gallstone Gallbladder-preserving surgery Recurrence Risk factors Nomogram

Observation of accurately designed bound states in the continuum in momentum space

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Photonics Research 2024年第4期12卷 638-647页

作者： JIAJU wu JINGGUANG CHEN XIN QI ZHIWEI GUO JIAJUN WANG FENG wu yong SUN YUNHUI LI HAITAO jianG LEI SHI jian ZI HONG CHEN MOE Key Laboratory of Advanced Micro-Structured Materials School of Physics Science and EngineeringTongji UniversityShanghai 200092China State Key Laboratory of Surface Physics Key Laboratory of Micro-and Nano-Photonic Structures(Ministry of Education)and Department of PhysicsFudan UniversityShanghai 200433China School of Optoelectronic Engineering Guangdong Polytechnic Normal UniversityGuangzhou 510665China

Bound states in the continuum(BICs)in artificial photonic structures have received considerable attention since they offer unique methods for the extreme field localization and enhancement of light-matter ***,the symmetry-protected BICs are located at high symmetric points,while the positions of accidental BICs achieved by tuning the parameters will appear at some points in momentum *** to now,to accurately design the position of the accidental BIC in momentum space is still a ***,we theoretically and experimentally demonstrate an accurately designed accidental BIC in a two-coupled-oscillator system consisting of bilayer gratings,where the optical response of each grating can be described by a single resonator *** changing the interlayer distance between the gratings to tune the propagation phase shift related to wave vectors,the position of the accidental BIC can be arbitrarily controlled in momentum ***,we present a general method and rigorous numerical analyses for extracting the polarization vector fields to observe the topological properties of BICs from the polarization-resolved transmission ***,an application of the highly efficient second harmonic generation assisted by quasi-BIC is *** work provides a straightforward strategy for manipulating BICs and studying their topological properties in momentum space.

关键词： polarization tuning resonator

Effects of maternal methyl donor intake during pregnancy on ileum methylation and function in an intrauterine growth restriction pig model

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1173-1189页

作者： Yan Lin jiangnan wu yong Zhuo Bin Feng Zhengfeng Fang Shengyu Xu jian Li Hua Zhao De wu Lun Hua Lianqiang Che Key Laboratory of Animal Disease‑Resistance Nutrition Animal Nutrition InstituteSichuan Agricultural UniversityChengdu 611130SichuanChina

Background Intrauterine growth retardation(IUGR)affects intestinal growth,morphology,and function,which leads to poor growth performance and high *** present study explored whether maternal dietary methyl donor(MET)supplementation alleviates IUGR and enhances offspring’s growth performance by improving intestinal growth,function,and DNA methylation of the ileum in a porcine IUGR *** Forty multiparous sows were allocated to the control or MET diet groups from mating until *** farrowing,8 pairs of IUGR and normal birth weight piglets from 8 litters were selected for sampling before suckling *** The results showed that maternal MET supplementation tended to decrease the IUGR incidence and increased the average weaning weight of ***,maternal MET supplementation significantly reduced the plasma concentrations of isoleucine,cysteine,urea,and total amino acids in sows and newborn *** also increased lactase and sucrase activity in the jejunum of newborn *** addition resulted in lower ileal methionine synthase activity and increased betaine homocysteine S-methyltransferase activity in the ileum of newborn *** methylation analysis of the ileum showed that MET supplementation increased the methyla-tion level of DNA CpG sites in the ileum of newborn ***-regulated differentially methylated genes were enriched in folic acid binding,insulin receptor signaling pathway,and endothelial cell *** contrast,up-regulated methylated genes were enriched in growth hormone receptor signaling pathway and nitric oxide biosyn-thetic *** Maternal MET supplementation can reduce the incidence of IUGR and increase the weaning litter weight of piglets,which may be associated with better intestinal function and methylation status.

关键词： Ileum Intrauterine growth restriction Methyl donor Methylation Sows

Enhanced visible-light photocatalytic hydrogen evolution using two-dimensional carbon nitride sheets with the removal of amine groups

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Chinese Chemical Letters 2024年第2期35卷 446-450页

作者： Yu Zhang Liting wu Shaopeng Wang Dingyi Yang Huan Liang Yizhang wu jian Hao Youqing Wang jianke Liu yong Wang Department of Physics Shaanxi University of Science and TechnologyXi'an 710021China School of Advanced Materials and Nanotechnology Academy of Advanced Interdisciplinary ResearchXidian UniversityXi'an 710126China The State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology Xidian UniversityXi'an 710126China Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State MicrostructuresNanjing UniversityNanjing 210093China State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China

Two-dimensional(2D)carbon nitride sheets(CNs)with atomically thin structures are regarded as one of the most promising materials for solar energy ***,due to their substantially enlarged bandgap caused by the strong quantum size effect and their incomplete polymerisation with a large number of non-condensed surface amino groups,the practical applicability of CNs in photocatalysis is *** this study,CNs with broad visible-light absorption were synthesised using a 5-min fast thermal *** removal of uncondensed amine groups reduces the bandgap of CNs from 3.06 eV to 2.60 eV,increasing their absorption of visible ***,the CNs were distorted after annealing,which can differentiate the spatial positions of electrons and holes,enhancing the visible-light absorption *** a result,when exposed to visible light,the photocatalytic hydrogen production activity of atomically thin 2D CNs rose by 8.38 *** research presents a dependable and speedy method for creating highly effective visible-light photocatalysts with narrowed bandgaps and improved visible-light absorption.

关键词： 2D carbon nitride sheets Rapid thermal annealing DFT calculations Visible-light absorption visible-light photocatalysis

Sirolimus-eluting stents for treatment of drug-eluting versus bare-metal stents restenosis： 42-month clinical outcomes from a Chinese single center

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Chinese Medical Journal 2012年第19期125卷 3398-3403页

作者： YAN Rong-qiang CHEN Ji-lin GAO Li-jian YANG Yue-jin LI jian-jun QIAO Shu-bin XU Bo YAO Min QIN Xue-wen LIU Hai-bo wu yong-jian YUAN Jin-qing CHEN Jue YOU Shi-jie DAI Jun GAO Run-lin State Key Laboratory of Cardiovascular Disease Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China

Background Restenosis of bare-metal stents （BMS） and drug-eluting stents （DES） has been increasingly treated with sirolimus-eluting stents （SES）, but the long-term outcomes are unknown. Methods In our study, 388 consecutive patients （144 DES restenosis and 244 BMS restenosis） with 400 lesions （147 DES restenosis and 253 BMS restenosis） treated with SES were included. The rates of target lesion revascularization （TLR） and major adverse cardiac events （MACE） at 42 months were analyzed. Results At the mean follow-up of 42 months, the rates of death （3.5% vs. 3.3%, P=1.000） and myocardial infarction （2.8% vs. 1.2%, P=0.431） in the DES group and BMS group were comparable. Compared with the BMS group, ischemia-driven TLR occurred with a higher frequency in the DES group （18.8% vs.10.7%, P=0.024）. This translated into an increased rate of MACE in the DES group （22.2% vs. 14.0%, P=0.034）. Stent thrombosis occurred with a similar frequency in both groups （2.8% vs. 1.6%, P=0.475）. Multivariate analysis showed that DES restenosis （OR=1.907, 95% Cl 1.108-3.285, P=0.020） and smoking （OR=2.069; 95% Cl 1.188-3.605; P=0.010） were independent predictors of MACE.

关键词： restenosis percutaneous coronary intervention drug-eluting stents