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Phosphine/Benzocyclone-based Neutral Nickel Catalysts for Ethylene Polymerization and Copolymerization with Polar Monomers

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Chinese Journal of Polymer Science 2024年第2期42卷 202-212,I0007页

作者： Fei Wang li Pan Vladislav A.Tuskaev Svetlana Ch.Gagieva yue-sheng li Tianjin Key Lab of Composite&Functional Materials School of Material Science and EngineeringTianjin UniversityTianjin300072China Department of Chemistry Lomonosov Moscow State UniversityRussian Federation InstitutionLeninskie Gory 1Moscow119991Russian Federation A N Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesVavilova st.28Moscow119991Russian Federation

The efficient copolymerization of olefin with polar monomers using nickel-based catalysts presents a longstanding challenge. In this contribution, three phosphine-benzocyclone ligands and corresponding neutral nickel catalysts(Ni1: Ar = Ph;Ni2: Ar = 2-(C_(6)H_(5))C_(6)H_(4);Ni3: Ar = 2-[2',6'-(Me O)_(2)-C_(6)H3]C_(6)H_(4)) were prepared and applied for the ethylene polymerization and copolymerization with polar monomers without any cocatalyst. The bulky substituent groups in complexes Ni2 and Ni3 contributed to high catalytic activities(up to 7.24×10^(6) and 9.04×10^(6)g·mol Ni^(-1)·h^(-1), respectively), and produced high-molecular-weight polyethylene(Mw up to 545.7 k Da). Complex Ni3 exhibited high activities for ethylene polymerization at the level of 10^(6) g·mol Ni^(-1)·h^(-1) across a wide range from 30 ℃ to 120 ℃, exhibiting excellent high temperature tolerance. These nickel complexes were also effectively employed in the copolymerization of ethylene with methyl acrylate, ethyl acrylate, butyl acrylate and lauryl acrylate, producing copolymers with high molecular weights(Mw up to 80.5 k Da) and high polar monomer incorporation(up to 8.2 mol%). Microstructure analyses revealed that the introduction of large sterically hindered substituents facilitated the incorporation of polar functional units into the polymer backbone. This study demonstrates the potential of these nickel-based catalysts for efficient copolymerization of olefin with polar monomers.

关键词： Neutral nickel catalyst Ethylene polymerization Copolymerization Polar acrylate monomers

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Isotropic sintering shrinkage of 3D glass-ceramic nanolattices:backbone preforming and mechanical enhancement

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International Journal of Extreme Manufacturing 2024年第2期6卷 418-426页

作者： Nianyao Chai Yunfan yue Xiangyu Chen Zhongle Zeng sheng li Xuewen Wang Center of Femtosecond Laser Manufacturing for Advanced Materials and Devices State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan 430070People’s Republic of China National Energy Key Laboratory for New Hydrogen-Ammonia Energy Technologies Foshan Xianhu LaboratoryFoshan 528000People’s Republic of China International School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070People’s Republic of China

There is a perpetual pursuit for free-form glasses and ceramics featuring outstanding mechanical properties as well as chemical and thermal resistance.It is a promising idea to shape inorganic materials in three-dimensional(3D)forms to reduce their weight while maintaining high mechanical properties.A popular strategy for the preparation of 3D inorganic materials is to mold the organic–inorganic hybrid photoresists into 3D micro-and nano-structures and remove the organic components by subsequent sintering.However,due to the discrete arrangement of inorganic components in the organic-inorganic hybrid photoresists,it remains a huge challenge to attain isotropic shrinkage during sintering.Herein,we demonstrate the isotropic sintering shrinkage by forming the consecutive–Si–O–Si–O–Zr–O–inorganic backbone in photoresists and fabricating 3D glass–ceramic nanolattices with enhanced mechanical properties.The femtosecond(fs)laser is used in two-photon polymerization(TPP)to fabricate 3D green body structures.After subsequent sintering at 1000℃,high-quality 3D glass–ceramic microstructures can be obtained with perfectly intact and smooth morphology.In-suit compression experiments and finite-element simulations reveal that octahedral-truss(oct-truss)lattices possess remarkable adeptness in bearing stress concentration and maintain the structural integrity to resist rod bending,indicating that this structure is a candidate for preparing lightweight and high stiffness glass–ceramic nanolattices.3D printing of such glasses and ceramics has significant implications in a number of industrial applications,including metamaterials,microelectromechanical systems,photonic crystals,and damage-tolerant lightweight materials.

关键词： 3D printing isotropic shrinkage femtosecond laser two-photon polymerization structural glass-ceramics

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Slicing capacity-centered mode selection and resource optimization for network-assisted full-duplex cell-free distributed massive MIMO systems

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Science China(Information Sciences) 2024年第1期67卷 203-220页

作者： Jie WANG Jiamin li Pengcheng ZHU Dongming WANG Hongbiao ZHANG yue HAO Bin sheng National Mobile Communications Research Laboratory Southeast University 2. Purple Mountain Laboratories China Mobile Research Institute

Network-assisted full-duplex(NAFD) cell-free distributed massive multiple-input multipleoutput(MIMO) systems enable uplink(UL) and downlink(DL) communications within the same timefrequency resources,which potentially reduce latency by avoiding the overhead of switching UL/DL modes.However,how to choose UL/DL modes remains an important factor affecting system performance.With the dramatic increase in the number of users and access points(APs),massive access brings significant overhead in the mode selection.Additionally,the different quality of service(QoS) among users also makes the effective utilization of resources difficult.As one of the most promising technologies in sixth-generation(6G),network slicing enables the adaptive configuration of limited UL/DL resources through the resource isolation assisted NAFD technique.Therefore,we propose a slicing capacity-centered scheme.Under this scheme,APs are motivated by slicing requirements and associated slices to form different subsystems.Collaborative mode selection and resource allocation are performed within each subsystem to reduce overhead and improve resource utilization.To implement this scheme efficiently,a double-layer deep reinforcement learning(DRL)mechanism is used to realize the joint optimization of mode selection and resource allocation.Simulation results show that the slicing capacity-centered scheme can effectively improve resource utilization and reduce overhead.

关键词： network-assisted full-duplex network slicing mode selection resource optimization deep reinforcement learning

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Conquer coronary artery perforation with magic hands

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Journal of Geriatric Cardiology 2024年第4期21卷 379-386页

作者： Yi-Lun ZOU Jian-Qiang li Ding-Yu WANG Yong-Tai GONG li sheng yue li Department of Cardiology the First Affiliated Hospital of Harbin Medical UniversityHarbinChina

Coronary artery perforation(CAP) poses a significant challenge for interventional cardiologists. Management of CAP depends on the location and severity of the perforation. The conventional method for addressing the perforation of large vessels involves the placement of a covered stent, while the perforation of distal and collateral vessels is typically managed using coils, autologous skin, subcutaneous fat, microspheres, gelatin sponge, thrombin or other substances. However, the above techniques have certain limitations and are not applicable in all scenarios. Our team has developed a range of innovative strategies for effectively managing CAP. This article provides an insightful review of the various tips and tricks for the treatment of CAP.

关键词： coronary sponge perforation

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Main controlling factor and mechanism of gas-in-place content of the Lower Cambrian shale from different sedimentary facies in the western Hubei area, South China

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Petroleum Science 2024年第3期21卷 1488-1507页

作者： Gang li Xian-Ming Xiao Bo-Wei Cheng Chen-Gang Lu yue Feng Dong-sheng li School of Energy Resources China University of Geosciences (Beijing) Frontiers Science Center for Deep-time Digital Earth China University of Geosciences (Beijing)

The Lower Cambrian shale gas in the western Hubei area, South China has a great resource prospect, but the gas-in-place（GIP） content in different sedimentary facies varies widely, and the relevant mechanism has been not well understood. In the present study, two sets of the Lower Cambrian shale samples from the Wells YD4 and YD5 in the western Hubei area, representing the deep-water shelf facies and shallowwater platform facies, respectively, were investigated on the differences of pore types, pore structure and methane adsorption capacity between them, and the main controlling factor and mechanism of their methane adsorption capacities and GIP contents were discussed. The results show that the organic matter（OM） pores in the YD4 shale samples are dominant, while the inorganic mineral（IM） pores in the YD5 shale samples are primary, with underdeveloped OM pores. The pore specific surface area（SSA） and pore volume（PV） of the YD4 shale samples are mainly from micropores and mesopores, respectively,while those of the YD5 shale samples are mainly from micropores and macropores, respectively. The methane adsorption capacity of the YD4 shale samples is significantly higher than that of the YD5 shale samples, with a maximum absolute adsorption capacity of 3.13 cm3/g and 1.31 cm3/g in average,respectively. Compared with the shallow-water platform shale, the deep-water shelf shale has a higher TOC content, a better kerogen type and more developed OM pores, which is the main mechanism for its higher adsorption capacity. The GIP content models based on two samples with a similar TOC content selected respectively from the Wells YD4 and YD5 further indicate that the GIP content of the deep-water shelf shale is mainly 3 4 m3/t within a depth range of 1000—4000 m, with shale gas exploration and development potential, while the shallow-water platform shale has normally a GIP content of little shale gas potential. Considering the geological and geochemical conditions of shale gas formation and preservation, the deep-w

关键词： Lower Cambrian shale Deep-water shelf facies Shallow-water platform facies Pore structure Methane adsorption Gas-in-place content Controlling factor

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Comparison of corrosion mechanisms of 510L low alloy steel treated by ACS and EPS techniques under various service environments

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Journal of Iron and Steel Research(International) 2024年第2期31卷 501-518页

作者： Bao-sheng liu Peng-fei Xu Shao-hua Zhang Yan-rui li li-ming Mou Jia-li li yue-zhong Zhang Pei-mao Fu Fa-cai Shi College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina College of Chemical and Biological Engineering Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina Technical Center Taiyuan Iron and Steel(Group)Co.Ltd.Taiyuan030003ShanxiChina

The corrosion mechanism of 510L low alloy steel treated by acid-cleaned surface(ACS)and eco-pickled surface(EPS)techniques in three simulated solutions(S0:atmospheric environment;S1:soil environment;S2:industrial environment)and the influence of interaction between different corrosive anions on corrosion were investigated.The results show that the total corrosion rates of samples in three simulated solutions were in order of S2>S0>S1,which is simultaneously correlated with initial corrosion dissolution processes as well as after the formation of corrosion products.HCO3−will inhibit the initial corrosion owing to the formation of films,whereas HSO3−will accelerate the dissolutions of the matrix based on the synergistic action of HSO3−and Cl−.On the other hand,there is no significant difference in corrosion rates between the samples treated by ACS and EPS techniques.The EPS technique that is safe,reusable and environmentally friendly can be further widely used in future work.

关键词： Corrosion mechanism Low alloy steel Simulated solution Surface technique Immersion time

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Recent advances in promising drugs for primary prevention of gastroesophageal variceal bleeding with cirrhotic portal hypertension

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 4-13页

作者： Ji-Yao sheng Zi-Fan Meng Qiao li Yong-sheng Yang Department of Hepatobiliary and Pancreatic Surgery the Second Hospital of Jilin UniversityChangchun 130041China Jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases the Second Hospital of Jilin UniversityChangchun 130041China

Background:Gastroesophageal variceal bleeding is one of the most severe complications of patients with cirrhosis.Although primary prevention drugs,including non-selectiveβ-blockers,have effectively reduced the incidence of bleeding,their efficacy is limited due to side effects and related contraindications.With recent advances in precision medicine,precise drug treatment provides better treatment efficacy.Data sources:literature search was conducted in PubMed,MEDliNE and Web of Science for relevant articles published up to May 2022.Information on clinical trials was obtained from https://clinicaltrials.gov/and http://***/.Results:The in-depth understanding of the pathogenesis and advances of portal hypertension has enabled the discovery of multiple molecular targets for promising drugs.According to the site of action,these drugs could be classified into four classes:intrahepatic,extrahepatic,both intrahepatic and extrahepatic targets and others.All these classes of drugs offer advantages over traditional treatments in prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.Conclusions:This review classified and summarized the promising drugs,which prevent gastroesophageal variceal bleeding by targeting specific markers of pathogenesis of portal hypertension,demonstrating the significance of using the precision medicine strategy to discover and develop promising drugs for the primary prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.

关键词： Cirrhotic portal hypertension Target drug Primary prevention Bleeding

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Gut microbiota intervention attenuates thermogenesis in broilers exposed to high temperature through modulation of the hypothalamic 5‑HT pathway

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Journal of Animal Science and Biotechnology 2024年第2期15卷 679-698页

作者： sheng li Xiaoqing li Kai Wang Yansen li Kentaro Nagaoka Chunmei li Research Centre for livestock Environmental Control and Smart Production College of Animal Science and TechnologyNanjing Agricultural UniversityNanjing 210095China Laboratory of Veterinary Physiology Department of Veterinary MedicineFaculty of AgricultureTokyo University of Agriculture and TechnologyTokyo 183‑8509Japan

Background Broilers have a robust metabolism and high body temperature,which make them less tolerant to hightemperature(HT)environments and more susceptible to challenges from elevated temperatures.Gut microbes,functioning as symbionts within the host,possess the capacity to significantly regulate the physiological functions and environmental adaptability of the host.This study aims to investigate the effects of gut microbial intervention on the body temperature and thermogenesis of broilers at different ambient temperatures,as well as the underlying mechanism involving the"gut-brain"axis.Methods Broilers were subjected to gut microbiota interference with or without antibiotics(control or ABX)starting at 1 day of age.At 21 day of age,they were divided into 4 groups and exposed to different environments for 7 d:The control and ABX groups at room temperature(RT,24±1℃,60%relative humidity(RH),24 h/d)and the control-HT and ABX-HT groups at high temperature(HT,32±1℃,60%RH,24 h/d).Results The results demonstrated that the antibiotic-induced gut microbiota intervention increased body weight and improved feed conversion in broiler chickens(Pliver(Plistipes was enriched in control chickens.In contrast,antibioticinduced gut microbiota intervention resulted in a decrease in the relative abundance of Alistipes(P<0.05).Moreover,this difference was accompanied by increased hypothalamic 5-hydroxytryptamine(5-HT)content and TPH2 expression(P<0.05).Conclusions These findings underscore the critical role

关键词： 5-HT Broiler chickens Gut microbiota Thermogenesis Thermoregulation

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Ti_(3)C_(2)T_(x)/SnO_(2)P–N heterostructure construction boosts room-temperature detecting formaldehyde

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Rare Metals 2024年第1期43卷 267-279页

作者： yue Zhang Ming-yue Wang Xiao-Guang San Yan-Bai Shen Guo-sheng Wang Lei Zhang Dan Meng College of Chemical Engineering Shenyang University of Chemical TechnologyShenyang 110142China Institute for Superconducting and Electronic Materials(ISEM) Australian Institute for Innovative Materials(AIIM)University ofWollongongWollongongNSW2500Australia College of Resources and Civil Engineering Northeastern UniversityShenyang 110819China

Formaldehyde is a common atmospheric pollutant produced in industrial production and daily life.However,the traditional semiconductor formaldehyde gas sensor cannot work at room temperature,which limits its practical application.Therefore,developing high-performance gas sensors for rapidly and accurately detecting formaldehyde at room temperature is an important topic.In this study,Ti_(3)C_(2)Tx/SnO_(2)heterostructures were constructed,which could selectively detect formaldehyde at room temperature with a response value of 29.16%(10×10^(-6)).In addition,the sensor shows a remarkable theoretical detection limit of 5.09×10^(-9)and good longterm stability.Density functional theory(DFT)simulations reveal that SnO_(2)nano spheres provide the majority of adsorption sites that strongly interact with formaldehyde.Meanwhile,Ti_(3)C_(2)T_(x)acting as a conductive layer facilitates the transfer of charge carriers so that they show a sensing response to formaldehyde at room temperature.Moreover,the formation of p-n heterostructures between SnO_(2)and Ti_(3)C_(2)T_(x)boosts the Schottky barrier at the interface,which is the critical factor in enhancing the sensing properties by turning the Schottky barrier upon introducing formaldehyde gas.This perspective is expected to provide instructive guidance for utilizing MXene/metal oxide nanocomposites to improve the gas sensing performance at room temperature.

关键词： Ti_(3)C_(2)T_(x)/SnO_(2)nanocomposites p-n heterostructures Formaldehyde sensing Room temperature DFT calculations

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Plexin domain-containing 1 may be a biomarker of poor prognosis in hepatocellular carcinoma patients,may mediate immune evasion

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2091-2112页

作者： Ming-yue Tang Xue Shen Run-sheng Yuan Hui-Yuan li Xin-Wei li Yi-Ming Jing yue Zhang Hong-Hong Shen Zi-Shu Wang Lei Zhou Yun-Chuan Yang He-Xin Wen Fang Su Department of Medical Oncology The First Affiliated Hospital of Bengbu Medical CollegeBengbu 233000Anhui ProvinceChina Otolaryngology and Head and Neck Surgery The First Affiliated Hospital of Bengbu Medical CollegeBengbu 233000Anhui ProvinceChina Department of Neurology The First Affiliated Hospital of Bengbu Medical CollegeBengbu 233000Anhui ProvinceChina Department of Hepatobiliary Surgery The First Affiliated Hospital of Bengbu Medical CollegeBengbu 233000Anhui ProvinceChina Department of Gastrointestinal Surgery The First Affiliated Hospital of Bengbu Medical CollegeBengbu 233000Anhui ProvinceChina

BACKGROUND For the first time,we investigated the oncological role of plexin domain-containing 1(PLXDC1),also known as tumor endothelial marker 7(TEM7),in hepatocellular carcinoma(HCC).AIM To investigate the oncological profile of PLXDC1 in HCC.METHODS Based on The Cancer Genome Atlas database,we analyzed the expression of PLXDC1 in HCC.Using immunohistochemistry,quantitative real-time polymerase chain reaction(qRT-PCR),and Western blotting,we validated our results.The prognostic value of PLXDC1 in HCC was analyzed by assessing its correlation with clinicopathological features,such as patient survival,methylation level,tumor immune microenvironment features,and immune cell surface checkpoint expression.Finally,to assess the immune evasion potential of PLXDC1 in HCC,we used the tumor immune dysfunction and exclusion(TIDE)website and immunohistochemical staining assays.RESULTS Based on immunohistochemistry,qRT-PCR,and Western blot assays,overexpression of PLXDC1 in HCC was associated with poor prognosis.Univariate and multivariate Cox analyses indicated that PLXDC1 might be an independent prognostic factor.In HCC patients with high methylation levels,the prognosis was worse than in patients with low methylation levels.Pathway enrichment analysis of HCC tissues indicated that genes upregulated in the high-PLXDC1 subgroup were enriched in mesenchymal and immune activation signaling,and TIDE assessment showed that the risk of immune evasion was significantly higher in the high-PLXDC1 subgroup compared to the low-PLXDC1 subgroup.The high-risk group had a significantly lower immune evasion rate as well as a poor prognosis,and PLXDC1-related risk scores were also associated with a poor prognosis.CONCLUSION As a result of this study analyzing PLXDC1 from multiple biological perspectives,it was revealed that it is a biomarker of poor prognosis for HCC patients,and that it plays a role in determining immune evasion status.

关键词： Plexin domain-containing 1 Biomarker Immune evasion Prognosis Immunotherapy Hepatocellular carcinoma

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