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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

Numerical investigations of the interactions between bubble induced shock waves and particle based on OpenFOAM

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Journal of Hydrodynamics 2024年第2期36卷 355-362页

作者： Jia-xin Yu jin-sen Hu Yu-hang Liu yi-fan Liu Dan Gao Yu-ning Zhang Key Laboratory of Power Station Energy Transfer Conversion and System Ministry of EducationSchool of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

The presence of particles and the shock waves generated by the cavitation bubbles can significantly affect the safety and the performance of hydrodynamic *** the present paper,the shock waves generated by cavitation bubble collapsing near the particle are numerically investigated based on the OpenFOAM together with the numerical schlieren for the shock wave *** numerical results reveal that the stand-off distance is one of the paramount factors affecting the interactions between the particle and the shock *** different kinds of shock waves(e.g.,bubble-inception,jet formation,particle reflected and jet-split shock waves)are observed during the bubble collapsing near the *** stand-off distance smaller than 0.5 or larger than 1.1,the maximum pressure at particle surface generated by the bubble growth can surpass those of the collapse stage.

关键词： Particle-bubble interaction shockwaves jetdynamics

Ultratough Yet Dynamic Crystalline Poly(thiourethane)Network Directly from Low Viscosity Precursors

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CCS Chemistry 2024年第3期6卷 682-692页

作者： Haijun Feng yi Sheng Guancong Chen Binjie jin Zizheng fang Bo Yang Xiaorui Zhou Wenxuan Wu Tao Xie ning Zheng State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058 Department of Colorectal Surgery and Oncology Key Laboratory of Cancer Prevention and InterventionMinistry of EducationThe Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310027

Thermosets based on direct curing of multifunctional monomers offer processing flexibility that thermoplastics cannot ***,this type of thermoset is typically amorphous since it is difficult to meet the stringent requirement of long-range molecular regularity for ***,we report here a crystallizable poly(thiourethane)thermoset synthesized directly from the curing of low-viscosity liquid precursors that does not employ any *** crystalline nature results in superior toughness,comparable to commercial high-density polyethylene,in sharp contrast to the brittleness of the typical,rigid,glassy thermoset *** that,the network polymer exhibits shape-memory behavior in which the crystalline transition is utilized for temporary shape fixing/recovery whereas the dynamic thiourethane bonds can be activated for bond exchange as a mechanism for complex shape *** with these combined features represent attractive options for demanding engineering applications due to their high performance and multifunctinality.

关键词： thermosets crystalline polymer thiourethane thermadapt

Fundamental Understanding of Hydrogen Evolution Reaction on Zinc Anode Surface:A First‑Principles Study

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Nano-Micro Letters 2024年第6期16卷 180-191页

作者： Xiaoyu Liu yiming Guo fang.ua ning Yuyu Liu Siqi Shi Qian Li Jiujun Zhang Shigang Lu jin yi Institute for Sustainable Energy&Department of Chemistry Shanghai UniversityShanghai 200444People’s Republic of China School of Materials Science and Engineering Shanghai UniversityShanghai 200444People’s Republic of China College of Materials Science and Engineering National Engineering Research Center for Magnesium AlloysChongqing UniversityChongqing 400044People’s Republic of China

Hydrogen evolution reaction(HER)has become a key factor affecting the cycling stability of aqueous Zn-ion batteries,while the corresponding fundamental issues involving HER are still ***,the reaction mechanisms of HER on various crystalline surfaces have been investigated by first-principle calculations based on density functional *** is found that the Volmer step is the ratelimiting step of HER on the Zn(002)and(100)surfaces,while,the reaction rates of HER on the Zn(101),(102)and(103)surfaces are determined by the Tafel ***,the correlation between HER activity and the generalized coordination number(CN)of Zn at the surfaces has been *** relatively weaker HER activity on Zn(002)surface can be attributed to the higher CN of surface Zn *** atomically uneven Zn(002)surface shows significantly higher HER activity than the flat Zn(002)surface as the CN of the surface Zn atom is *** CN of surface Zn atom is proposed as a key descriptor of HER *** the CN of surface Zn atom would be a vital strategy to inhibit HER on the Zn anode surface based on the presented theoretical ***,this work provides a theoretical basis for the in-depth understanding of HER on the Zn surface.

关键词： Aqueous Zn-ion battery Zn anode Hydrogen evolution reaction Coordination number First-principles calculation

维普期刊数据库

Characteristics of early gastric tumors with different differentiation and predictors of long-term outcomes after endoscopic submucosal dissection

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World Journal of Gastroenterology 2024年第14期30卷 1990-2005页

作者： Hong-yi Zhu Jie Wu Yuan-Miao Zhang fang-Lan Li jin Yang Bin Qin Jiong Jiang ning Zhu Meng-Yao Chen Bai-Cang Zou Department of Gastroenterology The Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710004Shaanxi ProvinceChina Department of Pathology The Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710004Shaanxi ProvinceChina Department of Gastroenterology Xianyang Hospital of Yan'an UniversityXianyang 712000Shaanxi ProvinceChina Department of Gastroenterology The First Hospital of Xi'anXi'an 710000Shaanxi ProvinceChina

BACKGROUND Gastric cancer is a common malignant tumor of the digestive tract,and endosco-pic submucosal dissection(ESD)is the preferred treatment for early-stage gastric *** analysis of the epidemiological characteristics of gastric mucosal tumors with different differentiation degrees and the influencing factors of long-term ESD efficacy may have certain significance for revealing the development of gastric cancer and *** To analyze the features of gastric mucosal tumors at different differentiation levels,and to explore the prognostic factors of *** We retrospectively studied 301 lesions in 285 patients at The Second Affiliated Hospital of Xi'an Jiaotong University from 2014 to 2021,according to the latest Japanese guidelines(sixth edition),and divided them into low-grade intrae-pithelial neoplasia(LGIN),high-grade intraepithelial neoplasia(HGIN),and computed tomography at 3,6 and 12 months after *** compared clinicopathologic characteristics,ESD efficacy,and complications with different degrees of differentiation,and analyzed the related factors associated with *** HGIN and differentiated carcinoma patients were significantly older compared with LGIN patients(P<0.001)and accounted for more 0-IIc(P<0.001),atrophic gastritis was common(P<0.001),and irregular microvascular patterns(IMVPs)and demarcation lines(DLs)were more obvious(P<0.001).There was more infiltration in the undifferentiated carcinoma tissue(P<0.001),more abnormal folds and poorer mucosal peristalsis(P<0.001),and more obvious IMVPs,irregular microsurface patterns and DLs(P<0.05)than in the LGIN and HGIN *** disease-free survival rates at 2,5,and 8 years after ESD were 95.0%,90.1%,and 86.9%,***-tiated lesions(HR 5.066),white moss(HR 7.187),incomplete resection(HR 3.658),and multiple primary cancers(HR 2.462)were significantly associated with poor *** Differentiations of gastric mucosal tumors have different epidemiological and

关键词： Gastric mucosal epithelial neoplasia Differentiated early gastric cancer Undifferentiated early gastric cancer Endoscopic submucosal dissection Long-term outcomes

Phosphine-Catalyzed [4+3] Annulation Reaction of Indole Derivatives with MBH Carbonates:A Facile Access to Indole-1,2-fused 1,4-Diazepinones and Azepines

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Chinese Journal of Chemistry 2024年第3期42卷 271-275页

作者： Yannan Zhu Haoran Jiang yi-ning Wang Faculty of Chemistry and Chemical Engineering Yancheng Institute of TechnologyYanchengJiangsu224051 China

A phosphine-catalyzed [4+3] annulation between dinucleophilic indole derivatives and Morita−Baylis−Hillman (MBH) carbonates was discovered by using the N1 and N4′/C4′ nucleophilicities of the indole precursors,in which indoles act as four atom synthons. This protocol provides an efficient and facile access to indole-1,2-fused 1,4-diazepinones and azepines in good to high yields in one step,which illustrates potential synthetic utilities in drug discovery.

关键词： Phosphine catalysis [4+3]Annulation Indole derivatives Nitrogen heterocycles Organocatalysis

Appendicitis combined with Meckel’s diverticulum obstruction, perforation, and inflammation in children: Three case reports

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World Journal of Clinical Cases 2024年第4期12卷 865-871页

作者： yi-Meng Sun Wang Xin Yu-fang Liu Zhe-Ming Guan Hao-Wen Du ning-ning Sun Yong-Dong Liu School of Clinical Medicine Weifang Medical UniversityWeifang 261000Shandong ProvinceChina Department of Pediatric Surgery Weifang People’s HospitalWeifang 261000Shandong ProvinceChina Department of Burn Surgery Weifang People’s HospitalWeifang 261000Shandong ProvinceChina

BACKGROUND Meckel’s diverticulum is a common congenital malformation of the small intestine,with the three most common complications being obstruction,per-foration,and *** date,only a few cases have been reported *** children,the clinical symptoms are similar to *** most of the imaging features are nonspecific,the preoperative diagnosis is not *** addition,the clinical characteristics are highly similar to pediatric acute appendicitis,thus special attention is necessary to distinguish Meckel’s diver-ticulum from pediatric *** with poor disease control should undergo laparoscopic exploration to avoid serious complications,including intestinal necrosis,intestinal perforation and gastrointestinal *** SUMMARY This report presents three cases of appendicitis in children combined with intestinal obstruction,which was caused by fibrous bands(ligaments)arising from the top part of Meckel's diverticulum,diverticular perforation,and diver-ticular *** three patients,aged 11-12 years,had acute appendicitis as their initial clinical *** were treated by laparoscopic surgery with a favorable outcome.A complete dataset including clinical presentation,dia-gnostic imaging,surgical information,and histopathologic findings was also *** Preoperative diagnosis of Meckel’s diverticulum and its complications is challenging because its clinical signs and complications are similar to those of appendicitis in *** combined with laparotomy is useful for diagnosis and treatment.

关键词： Meckel’s diverticulum Complications Intestinal obstruction Perforation Appendicitis in children Mesodiverticular band Ligament Diverticular disease Case report

Glaucoma surgery experiments using digital microscope-integrated optical coherence tomography and OCT-compatible instruments

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 105-113页

作者： Tianliang Jiang jinyu Fan ning Tang yi He Guohua Shi School of Biomedical Engineering(Suzhou)Division of Life Sciences and Medicine University of Science and Technology of China Hefei 230026 P.R.China Jiangsu Key Laboratory of Medical Optics Suzhou Institute of Biomedical Engineering and Technology Chinese Academy of Science Suzhou 215163P.R.China

There is a certain failure rate in traditional glaucoma surgery because of the lack of depth information in microscope *** this work,we present a digital microscope-integrated optical coherence tomography(MIOCT)system and several custom-made OCT-compatible instruments for glaucoma *** ophthalmologists were asked to perform trabeculectomy and canaloplasty on live porcine eyes using the system and *** surgery,a subjective feedback survey about the user experience was *** experiment results showed that our system can help surgeons easily locate important tissue structures during *** custom-made instruments also solved the shadowing problem in OCT *** preferred to use the system in their future practice.

关键词： Microscope-integrated optical coherence tomography OCT-compatible instruments glaucoma surgery trabeculectomy canaloplasty

Hyperspectral remote sensing identification of marine oil spills and emulsions using feature bands and double-branch dual-attention mechanism network

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Journal of Oceanology and Limnology 2024年第3期42卷 728-743页

作者： ning ZHANG Junfang YANG Shanwei LIU yi MA Jie ZHANG College of Oceanography and Space Informatics China University of PetroleumQingdao 266580China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao 266061China

The accurate identification of marine oil spills and their emulsions is of great significance for emergency response to oil spill *** selection of characteristic bands with strong separability helps to realize the rapid calculation of data on aircraft or in orbit,which will improve the timeliness of oil spill emergency *** the same time,the combination of spectral and spatial features can improve the accuracy of oil spill *** ground-based experiments were designed to collect measured airborne hyperspectral data of crude oil and its emulsions,for which the multiscale superpixel level group clustering framework(MSGCF)was used to select spectral feature bands with strong *** addition,the double-branch dual-attention(DBDA)model was applied to identify crude oil and its *** with the recognition results based on original hyperspectral images,using the feature bands determined by MSGCF improved the recognition accuracy,and greatly shortened the running ***,the characteristic bands for quantifying the volume concentration of water-in-oil emulsions were determined,and a quantitative inversion model was constructed and applied to the AVIRIS image of the deepwater horizon oil spill event in *** study verified the effectiveness of feature bands in identifying oil spill pollution types and quantifying concentration,laying foundation for rapid identification and quantification of marine oil spills and their emulsions on aircraft or in orbit.

关键词： hyperspectral image spectral analysis dimensionality reduction multiscale superpixel level group clustering framework(MSGCF) double-branch dual-attention(DBDA)

维普期刊数据库