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Effect of existence state of asphaltenes on the asphaltenes-wax interaction in wax deposition

Petroleum Science 2023年第1期20卷 507-514页

作者： Yun Lei Han Wang shuang-shuang li Xue-Qian liu Hao-Ran Zhu Yu-Ming Gao Hao-Ping Peng Peng-Fei Yu Jiangsu Key Laboratory of Oil and Gas Storage&Transportation Technology Changzhou UniversityJiangsu213164China

Asphaltenes are the most elusive substances in waxy crude oil,especially the complex structures,which leads to significant precipitation and aggregation characteristics of asphaltenes,and affects the asphaltenes-wax interaction.In this study,the concept of the existence state of asphaltenes was introduced to semi-quantitatively investigate the precipitation and aggregation characteristics of asphaltenes.On this basis,the influence of the existence state of asphaltenes on wax deposition was studied by coldfinger device and high-temperature gas chromatography,and the composition and properties of the deposits were analyzed.Four main findings were made:(1)As the asphaltene concentration increases,the existence state of asphaltenes gradually transitions from dispersed state to aggregated state,and the asphaltene concentration of 0.30 wt%in this study is the starting point of the transition.(2)The existence state of asphaltenes in crude oil does affect the process of wax deposition,as shown in the fact that the dispersed asphaltenes promote the occurrence of wax deposition,while the aggregated asphaltenes can inhibit wax deposition.(3)In the presence of the aggregated asphaltenes,that is,when the asphaltene concentration is higher than 0.30 wt%,the shedding phenomenon of deposit layer was observed,and with the increase of aggregated asphaltenes,the deposit layer fell off earlier.(4)With the increase of the dispersed asphaltenes,the wax appearance temperature(WAT)and wax content of the deposits all showed an increasing trend,while with the appearance of the aggregated asphaltenes,the above situation was reversed.The findings of this study can help for better understanding of the interaction between the asphaltenes and wax in wax deposition.

关键词： Asphaltenes Precipitation/aggregation Existence state of asphaltenes Deposition

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Emerging weak antilocalization effect in Ta_(0.7)Nb_(0.3)Sb_(2)semimetal single crystals

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Frontiers of physics 2023年第1期18卷 123-132页

作者： Meng Xu Lei Guo Lei Chen Ying Zhang shuang-shuang li Weiyao Zhao Xiaolin Wang Shuai Dong Ren-Kui Zheng College of Science Hohai UniversityNanjing 210098China School of Physics Southeast UniversityNanjing 211189China School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China School of Materials Science and Engineering Jiangxi Engineering Laboratory for Advanced Functional Thin FilmsNanchang UniversityNanchang 330031China Department of Materials Science&Engineering Monash UniversityClayton 3800 VICAustralia Institute for Superconducting and Electronic Materials &ARC Centre of Excellence in Future Low-Energy Electronics TechnologiesInnovation CampusUniversity of WollongongNorth Wollongong NSW 2500Australia

Weak antilocalization(WAL)effect is commonly observed in low-dimensional systems,three-dimensional(3D)topological insulators and semimetals.Here,we report the growth of high-quality Ta_(0.7)Nb_(0.3)Sb_(2)single crystals via the chemical vapor transport(CVT).Clear sign of the WAL effect is observed below 50 K,probably due to the strong spin–orbital coupling in 3D bulk.In addition,it is worth noting that a relatively large MR of 120%appears under 1 T magnetic field at T=2 K.Hall measurements and two-band model fitting results reveal high carrier mobility(>1000 cm^(2)·V^(–1)·s^(–1)in 2–300 K region),and off-compensation electron/hole ratio of~8:1.Due to the angular dependence of the WAL effect and the fermiology of the Ta_(0.7)Nb_(0.3)Sb_(2)crystals,interesting magnetic-field-induced changes of the symmetry of the anisotropic magnetoresistance(MR)from two-fold(≤0.6 T)to four-fold(0.8–1.5 T)and finally to two-fold(≥2 T)are observed.This phenomenon is attributed to the mechanism shift from the low-field WAL dominated MR to WAL and fermiology co-dominated MR and finally to high-field fermiology dominated MR.All these signs indicate that Ta_(0.7)Nb_(0.3)Sb_(2)may be a topological semimetal candidate,and these magnetotransport properties may attract more theoretical and experimental exploration of the(Ta,Nb)Sb_(2)family.

关键词： topological semimetal magnetoresistance weak antilocalization effect spin-orbital coupling

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Cinnamic acid regulates the intestinal microbiome and short-chain fatty acids to treat slow transit constipation

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World Journal of Gastrointestinal Pharmacology and Therapeutics 2023年第2期14卷 4-21页

作者： Jin-Guang Jiang Qian Luo shuang-shuang li Tian-Ying Tan Kai Xiong Tao Yang Tian-Bao Xiao Department of Colorectal and Anal Surgery Suqian Hospital of Traditional Chinese MedicineSuqian 223800Jiangsu ProvinceChina College of Clinical Medicine Guizhou University of Traditional Chinese MedicineGuiyang 550000Guizhou ProvinceChina Department of Colorectal and Anal Surgery The First Affiliated Hospital of Guizhou University of Traditional Chinese MedicineGuiyang 550000Guizhou ProvinceChina

BACKGROUND Slow transit constipation(STC)is a disorder with delayed colonic transit.Cinnamic acid(CA)is an organic acid in natural plants,such as Radix Scrophulariae(Xuan Shen),with low toxicity and biological activities to modulate the intestinal microbiome.AIM To explore the potential effects of CA on the intestinal microbiome and the primary endogenous metabolites-short-chain fatty acids(SCFAs)and evaluate the therapeutic effects of CA in STC.METHODS Loperamide was applied to induce STC in mice.The treatment effects of CA on STC mice were assessed from the 24 h defecations,fecal moisture and intestinal transit rate.The enteric neurotransmitters:5-hydroxytryptamine(5-HT)and vasoactive intestinal peptide(VIP)were determined by the enzyme-linked immunosorbent assay.Hematoxylin-eosin and Alcian blue and Periodic acid Schiff staining were used to evaluate intestinal mucosa's histopathological performance and secretory function.16S rDNA was employed to analyze the composition and abundance of the intestinal microbiome.The SCFAs in stool samples were quantitatively detected by gas chromatography-mass spectrometry.RESULTS CA ameliorated the symptoms of STC and treated STC effectively.CA ameliorated the infiltration of neutrophils and lymphocytes,increased the number of goblet cells and acidic mucus secretion of the mucosa.In addition,CA significantly increased the concentration of 5-HT and reduced VIP.CA significantly improved the diversity and abundance of the beneficial microbiome.Furthermore,the production of SCFAs[including acetic acid(AA),butyric acid(BA),propionic acid(PA)and valeric acid(VA)]was significantly promoted by CA.The changed abundance of Firmicutes,Akkermansia,Lachnoclostridium,Monoglobus,UCG.005,Paenalcaligenes,Psychrobacter and Acinetobacter were involved in the production of AA,BA,PA and VA.CONCLUSION CA could treat STC effectively by ameliorating the composition and abundance of the intestinal microbiome to regulate the production of SCFAs.

关键词： Slow transit constipation Cinnamic acid Intestinal microbiome Short-chain fatty acids Intestinal motility

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IQABC-Based Hybrid Deployment Algorithm for Mobile Robotic Agents Providing Network Coverage

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Tsinghua Science and Technology 2024年第2期29卷 589-604页

作者： shuang Xu Xiaojie liu Dengao li Jumin Zhao College of Computer Science and Technology(College of Data Science) Taiyuan University of TechnologyTaiyuan 030024China Pengcheng Laboratory Shenzhen 518055China College of Information and Computer Taiyuan University of TechnologyTaiyuan 030024China

Working as aerial base stations,mobile robotic agents can be formed as a wireless robotic network to provide network services for on-ground mobile devices in a target area.Herein,a challenging issue is how to deploy these mobile robotic agents to provide network services with good quality for more users,while considering the mobility of on-ground devices.In this paper,to solve this issue,we decouple the coverage problem into the vertical dimension and the horizontal dimension without any loss of optimization and introduce the network coverage model with maximum coverage range.Then,we propose a hybrid deployment algorithm based on the improved quick artificial bee colony.The algorithm is composed of a centralized deployment algorithm and a distributed one.The proposed deployment algorithm deploy a given number of mobile robotic agents to provide network services for the on-ground devices that are independent and identically distributed.Simulation results have demonstrated that the proposed algorithm deploys agents appropriately to cover more ground area and provide better coverage uniformity.

关键词： wireless robotic networks network coverage deployment algorithm improved quick artificial bee colony

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Base editor-mediated large-scale screening of functional mutations in bacteria for industrial phenotypes

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Science China(life Sciences) 2024年第5期67卷 1051-1060页

作者： Yaomeng Yuan Xihao liao shuang li Xin-Hui Xing Chong Zhang MOE Key Laboratory for Industrial Biocatalysis Institute of Biochemical EngineeringDepartment of Chemical EngineeringTsinghua UniversityBeijing 100084China Institute of Biopharmaceutical and Health Engineering Tsinghua Shenzhen International Graduate SchoolShenzhen 518055China Institute of Biomedical Health Technology and Engineering Shenzhen Bay LaboratoryShenzhen 440300China Center for Synthetic and Systems Biology Tsinghua UniversityBeijing 100084China

Base editing,the targeted introduction of point mutations into cellular DNA,holds promise for improving genome-scale functional genome screening to single-nucleotide resolution.Current efforts in prokaryotes,however,remain confined to loss-of-function screens using the premature stop codons-mediated gene inactivation library,which falls far short of fully releasing the potential of base editors.Here,we developed a base editor-mediated functional single nucleotide variant screening pipeline in Escherichia coli.We constructed a library with 31,123 sgRNAs targeting 462 stress response-related genes in E.coli,and screened for adaptive mutations under isobutanol and furfural selective conditions.Guided by the screening results,we successfully identified several known and novel functional mutations.Our pipeline might be expanded to the optimization of other phenotypes or the strain engineering in other microorganisms.

关键词： base editor high-throughput large-scale screening Escherichia coli functional mutation

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Differential depression of the glacier equilibrium-line altitudes in the Yarlung Zangbo Downstream Basin in the Last Glacial Maximum compared to the pre-industrial era

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Journal of Geographical Sciences 2024年第6期34卷 1157-1173页

作者： li Hao liU shuang HU Kaiheng ZHANG Xiaopeng State Key Laboratory of Mountain Hazards and Engineering Resilience Institute of Mountain Hazards and EnvironmentCASChengdu 610299China University of Chinese Academy of Sciences Beijing 100049China

Glaciers in the Yarlung Zangbo Downstream Basin(YZDB) are sensitive to global climate change. The equilibrium-line altitude(ELA) is a key indicator of glacial development.Current models for simulating the meteorological ELA underestimate the extent of glacial advance during the Last Glacial Maximum(LGM) in the YZDB and cannot explain the large-scale glacial extension compared with the Yarlung Zangbo Midstream Basin(YZMB). In this study, the distribution of ELA in the LGM is reconstructed using high-resolution 80-km ECHAM5 simulations and empirical relationships between temperature and precipitation.Changes in ELA between the LGM and pre-industrial era(PI) are compared. Our simulated ELA closely fits the published field data. In the YZDB, simulated LGM ELAs range from ca.3500 m to over 4900 m, representing declines of ca. 300–950 m. The ECHAM5 simulations better reflect the complex topographic features than most coarse-resolution climate models,and the ELA distribution is controlled by the spatial arrangement of river valley systems and mountain ranges and their impact on precipitation. Compared with the PI era, most of the monsoon precipitation in the LGM was concentrated in the YZDB, which is the main driver of glacial extension and the differential response of the downstream and midstream basins.

关键词： glacier extension glacier equilibrium-line altitudes Yarlung Zangbo Downstream Basin southeastern Tibetan Plateau high-resolution paleoclimate simulations

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Resilience assessment and optimization method of city road network in the post-earthquake emergency period

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 765-779页

作者： Wang Haoran Xiao Jia li shuang Zhai Changhai Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information TechnologyHarbin Institute of TechnologyHarbin 150090China

The post-earthquake emergency period,which is a sensitive time segment just after an event,mainly focuses on saving life and restoring social order.To improve the seismic resilience of city road networks,a resilience evaluation method used in the post-earthquake emergency period is proposed.The road seismic damage index of a city road network can consider the influence of roads,bridges and buildings along the roads,etc.on road capacity after an earthquake.A function index for a city road network is developed,which reflects the connectivity,redundancy,traffic demand and traffic function of the network.An optimization model for improving the road repair order in the post-earthquake emergency period is also developed according to the resilience evaluation,to enable decision support for city emergency management and achieve the best seismic resilience of the city road network.The optimization model is applied to a city road network and the results illustrate the feasibility of the resilience evaluation and optimization method for a city road network in the post-earthquake emergency period.

关键词： city road network post-earthquake emergency period traffic demand resilience evaluation optimization model

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Precision targeting in hepatocellular carcinoma:Exploring ligandreceptor mediated nanotherapy

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World Journal of Hepatology 2024年第2期16卷 164-176页

作者： Xia-Qing Zhou Ya-Ping li shuang-Suo Dang Department of Infectious Diseases Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710004Shaanxi ProvinceChina

Hepatocellular carcinoma(HCC)is the most common primary liver cancer and poses a major challenge to global health due to its high morbidity and mortality.Conventional chemotherapy is usually targeted to patients with intermediate to advanced stages,but it is often ineffective and suffers from problems such as multidrug resistance,rapid drug clearance,nonspecific targeting,high side effects,and low drug accumulation in tumor cells.In response to these limitations,recent advances in nanoparticle-mediated targeted drug delivery technologies have emerged as breakthrough approaches for the treatment of HCC.This review focuses on recent advances in nanoparticle-based targeted drug delivery systems,with special attention to various receptors overexpressed on HCC cells.These receptors are key to enhancing the specificity and efficacy of nanoparticle delivery and represent a new paradigm for actively targeting and combating HCC.We comprehensively summarize the current understanding of these receptors,their role in nanoparticle targeting,and the impact of such targeted therapies on HCC.By gaining a deeper understanding of the receptor-mediated mechanisms of these innovative therapies,more effective and precise treatment of HCC can be achieved.

关键词： Targeting Hepatocellular carcinoma Receptor Nanomedicine Chemotherapy

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Effect of aflibercept combined with triamcinolone acetonide on aqueous humor growth factor and inflammatory mediators in diabetic macular edema

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 297-303页

作者： De-shuang li Hong-Xia liao Jing-lin Zhang Bo Qin Shenzhen Aier Eye Hospital Aier Eye HospitalJinan UniversityShenzhen 518031Guangdong ProvinceChina Guangzhou Aier Eye Hospital Jinan UniversityGuangzhou 510040Guangdong ProvinceChina

AIM:To investigate the efficacy of aflibercept combined with sub-tenon injection of triamcinolone acetonide(TA)in treating diabetic macular edema(DME)and to examine changes in growth factors and inflammatory mediator levels in aqueous humor after injection.METHODS:Totally 67 DME patients(67 eyes)and 30 cataract patients(32 eyes)were enrolled as the DME group and the control group,respectively.The DME group was divided into the aflibercept group(34 cases)and the aflibercept combined with TA group(combined group,33 cases).The aqueous humor of both groups was collected during the study period.The aqueous levels of vascular endothelial growth factor(VEGF),monocyte chemoattractant protein-1(MCP-1),interleukin-6(IL-6),interleukin-8(IL-8),and interleukin-1β(IL-1β)were detected using a microsphere suspension array technology(Luminex 200TM).Aqueous cytokines,best-corrected visual acuity(BCVA),central macular thickness(CMT),and complications before and after treatment were compared between the aflibercept group and combined group.RESULTS:The concentrations of VEGF,MCP-1,IL-6,and IL-8 in the aqueous humor were significantly higher in the DME group than those of the control group(all Plibercept group(all P0.05).CONCLUSION:The cytokines VEGF,MCP-1,IL-6,and IL-8 in the aqueous humor of DME patients are significantly increased.Aflibercept and aflibercept combined with TA have good efficacy in DME patients,can effectively reduce CMT,improve the patient’s vision,and have high safety.Aflibercept combined with TA can quickly downregulate the aqueous humor cytokines and help to relieve macular edema rapidly.However,the long-term efficacy is comparable to that of aflibercept alone

关键词： diabetic macular edema aqueous humor cytokines aflibercept triamcinolone acetonide

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Charge regulation by ferromagnetic metal/liF spin-polarized interface for high-performance li metal anodes

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Rare Metals 2024年第3期43卷 995-1005页

作者： Ming-Yang Feng shuang Zhou Yi-Fang Zhang Ya-Ping Wang Chun-Yan Fu Jian-Wen li Yuan-Lang Wan Zhi-Jia Zhang Yong Jiang An-Qiang Pan State Key Laboratory of Powder Metallurgy School of Materials Science and EngineeringCentral South UniversityChangsha410083China State Key Laboratory of Separation Membranes and Membrane Processes Tianjin Key Laboratory of Advanced Fibers and Energy StorageSchool of Material Science and EngineeringTiangong UniversityTianjin300387China School of Materials Science and Engineering Hebei University of TechnologyTianjin300130China

The interfacial characteristics of the li metal anode(LMA)play a crucial role in its overall performance.Despite various materials being applied to modify the interface,a comprehensive understanding of their specific mechanisms remains to be investigated.Herein,we have prepared carbon cloth(CC)frameworks with their surfaces modified using ferromagnetic metal/liF heterogeneous films(T^(M)-liF-CC)as the substrate for LMA,which exhibit superior electrochemical performance.Utilizing ferromagnetic Co as a representative example,our study demonstrates that the enhanced performance of Co-liF-CC,compared to bare CC,is attributed to the spinpolarized interface contributed by the Co/liF heterostructure.Co and liF play individual roles in redistributing electrons and li^(+)to promote homogeneous li deposition.Co nanoparticles play a crucial role in generating strong surface capacitance by storing electrons in spin-split bands,while liF,with low surface diffusion barriers,ensures fast transportation of li^(+).The Co-liF-CC@li electrodes deliver long lives of 7400 and 3600 h at 1 and 2 mA·cm^(-2)in symmetric cells,respectively;moreover,they enable full batteries with high and durable capacities,particularly when the N/P ratios are low(3.3 or even 1.7).

关键词： lithium metal anode Interfacial charge Ferromagnetic metal lithium fluoride Spin polarization

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