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High Temperature Iron Ethylene Polymerization Catalysts Bearing N,N,N'-2-(1-(2,4-Dibenzhydryl-6-fluorophenylimino)ethyl)-6-(1-(arylphenylimino)ethyl)pyridines

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Chinese Journal of Polymer Science 2024年第2期42卷 188-201,I0007页

作者： Chantsalnyam Bariashir Qiu-yue Zhang Bayasgalan Ulambayar Gregory A.Solan tong-Ling Liang Wen-Hua Sun Institute of Chemistry and Chemical Technology Mongolian Academy of SciencesUlaanbaatar13330Mongolia Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China Department of Chemistry University of LeicesterUniversity RoadLeicesterLE17RHUK State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China

The N,N,N'-ferrous chloride complexes,[2-{CMeN(2,4-(CHPh)_(2)-6-FC_(6)H_(2))}-6-(CMeNAr)C_(5)H_(3)N]FeCl_(2)(Ar=2,6-Me_(2)C_(6)H_(3) Fe1,2,6-Et_(2)C_(6)H_(3)Fe2,2,6-^(i)Pr_(2)C_(6)H_(3) Fe3,2,4,6-Me_(3)C_(6)H_(2) Fe4 and 2,6-Et_(2)-4-MeC_(6)H_(2) Fe5),each possessing one N-2,4-dibenzhydryl-6-fluorophenyl group,were readily synthesized from their respective unsymmetrical bis(imino)pyridines,*** identification of Fe2 highlighted the variation in the steric properties provided by the dissimilar N-aryl *** pre-treatment with either MAO or MMAO,complexes Fe1-Fe5 all displayed,at an operating temperature of 80℃,high activities for ethylene polymerization with levels falling in the order:Fe4> Fe1> Fe5> Fe2> ***,Fe4/MAO displayed the highest activity of 1.94×10^(7) g_(PE)·mol_(Fe)^(-1)·h^(-1) of the study with only a modest loss in performance at 90℃.Generally,the resulting polyethylenes were highly linear(T_(m) range:122-132℃),narrowly disperse and of low molecular weight(M_(w) range:6.73-46.04kg·mol^(-1)),with the most sterically hindered Fe3 forming the highest molecular weight polymer of the ***-group analysis by ^(1)H-and ^(13)CNMR spectroscopy revealed saturated alkyl(n-propyl and i-propyl) and unsaturated vinyl chain ends indicative of the role of both β-H elimination and chain transfer to aluminum as termination *** comparison with previou sly reported iron precatalysts with similar tridentate ligand skeletons,it is evident that the introduction of a large benzhydryl group in combination with a fluorine as the ortho-substituents of one N-aryl group has the effect of enhancing thermal stability of the iron polymerization catalyst whilst maintaining appreciable polymer molecular weight.

关键词： Iron catalyst Ethylene polymerization Linear polyethylene Fluoride effect Thermal stability

A bifunctional nitrile additive for high-performance lithiumoxygen batteries

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Nano Research 2024年第7期17卷 6119-6126页

作者： Ziwei Li yue Yu Dongyue Yang Jin Wang Junmin Yan Gang Huang tong Liu Xinbo Zhang Key Laboratory of Automobile Materials Ministry of EducationDepartment of Materials Science and EngineeringJilin UniversityChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Chemistry and Waterloo Institute for Nanotechnology University of Waterloo200 University Ave.W.WaterlooOntario N2L 3G1Canada School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Li-O_(2)batteries with high energy density hold significant promise as next-generation energy storage ***,Li-O_(2)batteries have poor cycling performance at high current densities and large capacities,primarily due to the high impedance caused by the instability of the lithium anode and the sluggish kinetics in the discharge products decomposition on the ***,we investigated a bifunctional nitrile additive(2-methoxy benzonitrile(2-MBN))with good chemical/electrochemical stability to improve the performances of Li-O_(2)*** 2-MBN could actively modify the anode by ensuring uniform Li+deposition and optimizing the composition of solid electrolyte interphase(SEI).Meanwhile,it could also facilitate the decomposition of discharge products by inducing the formation of sheet-like Li_(2)O_(2),significantly reducing the battery charge *** bifunctional effects of 2-MBN for the anode and cathode enable Li-O_(2)batteries to achieve a stable lifetime of 97 cycles at a current density of 600 mA·g^(−1)with a fixed capacity of 2000 mAh·g^(−1),much better than that of Li-O_(2)batteries without 2-MBN(28 cycles).The inclusion of 2-MBN provides an effective approach for attaining high-performance Li-O_(2)batteries.

关键词： nitrile additives Li-O_(2)batteries lithium metal anode charge overpotential

Solving Generalized Non-degenerate Two-Mode Two-Photon Jaynes-Cummings Model by Supersymmetric Unitary Transformation

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Communications in Theoretical Physics 2002年第7期38卷 85-88页

作者： SONG tong-Qiang ZHU yue-Jin Department of Physics Ningbo University Ningbo 315211 China Department of Physics Ningbo University Ningbo 315211 China

Based on supersymmetric quantum mechanics theory, we introduced a supersymmetric unitary transfor mation to diagonalize the Hamiltonian of non-degenerate two-mode two-photon Jaynes-Cummings models which include any forms of intensity-dependent coupling, field-dependent detuning, and field nonlinearity. Its eigenvalue, eigenstates,and time evolution of state vector are obtained.

关键词： supersymmetric unitary transformation, Jaynes-Cumnings model

Statistical Channel Modeling for Indoor VLC Communications Based on Channel Measurements

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China Communications 2024年第1期21卷 131-147页

作者： Shuo Liu Pan Tang Jianhua Zhang yue Yin Yu tong Baobao Liu Guangyi Liu Liang Xia State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China China Mobile Research Institute Beijing 100053China

Visible light communication(VLC)has attracted much attention in the research of sixthgeneration(6G)***,channel modeling is the foundation for designing efficient and robust VLC *** this paper,we present extensive VLC channel measurement campaigns in indoor environments,i.e.,an office and a *** on the measured data,the large-scale fading characteristics and multipath-related characteristics,including omnidirectional optical path loss(OPL),K-factor,power angular spectrum(PAS),angle spread(AS),and clustering characteristics,are analyzed and modeled through a statistical *** on the extracted statistics of the above-mentioned channel characteristics,we propose a statistical spatial channel model(SSCM)capable of modeling multipath in the spatial ***,the simulated statistics of the proposed model are compared with the measured *** instance,in the office,the simulated path loss exponent(PLE)and the measured PLE are 1.96and 1.97,***,the simulated medians of AS and measured medians of AS are 25.94°and 24.84°,***,the fact that the simulated results fit well with measured results has demonstrated the accuracy of our SSCM.

关键词： channel characteristics channel measurement channel modeling 6G spatial lobe VLC

Digital measuring the ocular morphological parameters of guinea pig eye in vivo with Python

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 239-246页

作者： yue Di Zhong-Bao Qiao Hai-Yun Ye Xin-yue Li Wen-Ting Luo Wang-Yi Fang tong Qiao Department of Ophthalmology Shanghai Children’s HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200062China

AIM:To quantitatively measure ocular morphological parameters of guinea pig with Python ***:Thirty-six eyeballs of eighteen 3-weekold guinea pigs were measured with keratometer and photographed to obtain the horizontal,coronal,and sagittal planes *** corresponding photo pixels-actual length ratio was acquired by a proportional *** edge coordinates were identified artificially by ginput *** and conic curve fitting were applied to fit the contour of the eyeball in the sagittal,coronal and horizontal *** curvature,curvature radius,eccentricity,tilt angle,corneal diameter,and binocular separation angle were calculated according to the geometric ***,the eyeballs were removed,canny edge detection was applied to identify the contour of eyeball in *** results were compared between in vivo and in ***:Regarding the corneal curvature and curvature radius on the horizontal and sagittal planes,no significant differences were observed among results in vivo,in vitro,and the *** horizontal and vertical binocular separation angles were 130.6°±6.39°and 129.8°±9.58°*** the corneal curvature radius and eccentricity in vivo,significant differences were observed between horizontal and vertical ***:The Graphical interface window of Python makes up the deficiency of edge detection,which requires too much definition in *** are significant differences between guinea pig and human beings,such as exotropic eye position,oblique oval eyeball,and obvious discrepancy of *** study helps evaluate objectively the ocular morphological parameters of small experimental animals in emmetropization research.

关键词： ocular morphological parameters guinea pig digital measurement Python

Human umbilical cord-derived mesenchymal stem cells promote repair of neonatal brain injury caused by hypoxia/ischemia in rats

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Neural Regeneration Research 2022年第11期17卷 2518-2525页

作者： Yang Jiao yue-tong Sun Nai-Fei Chen Li-Na Zhou Xin Guan Jia-Yi Wang Wen-Juan Wei Chao Han Xiao-Lei Jiang Ya-Chen Wang Wei Zou Jing Liu Stem Cell Clinical Research Center National Joint Engineering LaboratoryRegenerative Medicine CenterThe First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina Dalian Innovation Institute of Stem Cells and Precision Medicine DalianLiaoning ProvinceChina Department of Neurology The First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina College of Life Science Liaoning Normal UniversityDalianLiaoning ProvinceChina

Administration of human umbilical cord-derived mesenchymal stem cells(hUC-MSCs)is believed to be an effective method for treating neurodevelopmental disorde *** this study,we investigated the possibility of hUC-MSCs treatment of neonatal hypoxic/ischemic brain injury associated with maternal immune activation and the underlying *** established neonatal rat models of hypoxic/ischemic brain injury by exposing pregnant rats to lipopolysaccharide on day 16 or 17 of *** offspring were intranasally administe red hUC-MSCs on postnatal day *** found that polypyrimidine tract-binding protein-1(PTBP-1)participated in the regulation of lipopolysaccharide-induced maternal immune activation,which led to neonatal hypoxic/ischemic brain *** delive ry of hUC-MSCs inhibited PTBP-1 expression,alleviated neonatal brain injury-related inflammation,and regulated the number and function of glial fibrillary acidic protein-positive astrocytes,there by promoting plastic regeneration of neurons and im p roving brain *** findings suggest that hUC-MSCs can effectively promote the repair of neonatal hypoxic/ischemic brain injury related to maternal immune activation through inhibition of PTBP-1 expression and astrocyte activation.

关键词： developmental brain disease model disease-associated astrocytes intranasal administration lipopolysaccharide maternal immune activation neonatal brain injury neuroplasticity repair polypyrimidine tract-binding protein-1 stem cell therapy umbilical cord-derived mesenchymal stem cells

Persistent greening against drying in northeast Asian semiarid grasslands:Asymmetrical responses of direct and legacy effects to intensified drought

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Advances in Climate Change Research 2024年第1期15卷 9-20页

作者： Yu-tong MA Hai-Shan CHEN Yao-Ming SONG Bo-Tao ZHOU Shan-Lei SUN Xin-Guan DU yue SUN Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China School of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing 210044China

Despite experiencing a decadal shift towards drought conditions at the end of the 2Oth century,semiarid grasslands in northeast Asia(NEA)exhibited an evident greening trend from 1982 to ***,the mechanism behind this phenomenon remains ***,we analysed the interdecadal changes in vegetation response to drought on the basis of the standardised precipitation evapotranspiration index(SPEI)and Global Inventory Modelling and Mapping Studies LAI4g datasets,with an emphasis on the differences between direct and legacy effects(as measured by resilience),to explore the mechanism of persistent grassland *** revealed that during the post-drought shift period(2000-2020),the sudden decrease in the water content of the intermediate soil layer triggered an intensified vegetation response to ***,although direct effects and resilience were amplified,they exhibited asymmetric *** was stronger than direct effects,and this difference increased with increasing drought(drought recovery)*** combined effects may account for persistent greening against intensified drying in the semiarid grasslands in *** the projected exacerbation of future droughts,this study holds notable importance for comprehending the long-term change dynamics of dryland ecosystems.

关键词： Semiarid grassland Drought decadal shift Direct effect Legacy effect(resilience) Northeast Asia

Evaluation of the efficacy and safety of endoscopic band ligation in the treatment of bleeding from mild to moderate gastric varices type 1

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World Journal of Gastroenterology 2024年第5期30卷 440-449页

作者： yue Deng Ya Jiang tong Jiang Ling Chen Hai-Jun Mou Bi-Guang Tuo Guo-Qing Shi Department of Gastroenterology Digestive Disease HospitalThe Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Department of Gastroenterology Guizhou Hospital of the First Affiliated HospitalSun Yat-sen UniversityGuiyang 550000Guizhou ProvinceChina Department of Gastroenterology Yinjiang Autonomous County People’s HospitalTongren 554300Guizhou ProvinceChina

BACKGROUND According to practice guidelines,endoscopic band ligation(EBL)and endoscopic tissue adhesive injection(TAI)are recommended for treating bleeding from esophagogastric ***,EBL and TAI are known to cause serious complications,such as hemorrhage from dislodged ligature rings caused by EBL and hemorrhage from operation-related ulcers resulting from ***,the optimal therapy for mild to moderate type 1 gastric variceal hemorrhage(GOV1)has not been ***,the aim of this study was to discover an individualized treatment for mild to moderate *** To compare the efficacy,safety and costs of EBL and TAI for the treatment of mild and moderate *** A clinical analysis of the data retrieved from patients with mild or moderate GOV1 gastric varices who were treated under endoscopy was also *** were allocated to an EBL group or an endoscopic TAI *** differences in the incidence of varicose relief,operative time,operation success rate,mortality rate within 6 wk,rebleeding rate,6-wk operation-related ulcer healing rate,complication rate and average operation cost were compared between the two groups of *** The total effective rate of the two treatments was similar,but the efficacy of EBL(66.7%)was markedly better than that of TAI(39.2%)(P<0.05).The operation success rate in both groups was 100%,and the 6-wk mortality rate in both groups was 0%.The average operative time(26 min)in the EBL group was significantly shorter than that in the TAI group(46 min)(P<0.01).The rate of delayed postoperative rebleeding in the EBL group was significantly lower than that in the TAI group(11.8%vs 45.1%)(P<0.01).At 6 wk after the operation,the healing rate of operation-related ulcers in the EBL group was 80.4%,which was significantly greater than that in the TAI group(35.3%)(P<0.01).The incidence of postoperative complications in the two groups was *** average cost and other related economic factors were g

关键词： Gastric varices Type 1 gastric variceal hemorrhage Endoscopic band ligation Tissue adhesive injection

Atorvastatin, etanercept and the nephrogenic cardiac sympathetic remodeling in chronic renal failure rats

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Journal of Geriatric Cardiology 2024年第4期21卷 443-457页

作者： Jing-yue XU Zheng-Kai XUE Ya-Ru ZHANG Xing LIU Xue ZHANG Xi YANG tong LIU Kang-Yin CHEN Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease Department of CardiologyTianjin Institute of Cardiologythe Second Hospital of Tianjin Medical UniversityTianjinChina

BACKGROUND Chronic renal failure(CRF) patients are predisposed to arrhythmias, while the detailed mechanisms are unclear. We hypothesized the chronic inflammatory state of CRF patients may lead to cardiac sympathetic remodeling, increasing the incidence of ventricular arrhythmia(VA) and sudden cardiac death. And explored the role of atorvastatin and etanercept in this *** A total of 48 rats were randomly divided into sham operation group(Sham group), CRF group, CRF + atorvastatin group(CRF + statin group), and CRF + etanercept group(CRF + rhTNFR-Fcgroup). Sympathetic nerve remodeling was assessed by immunofluorescence of growth-associated protein 43(GAP-43) and tyrosine hydroxylase positive area fraction. Electrophysiological testing was performed to assess the incidence of VA by assessing the ventricular effective refractory period and ventricular fibrillation threshold. The levels of tumor necrosis factor-alpha(TNF-α) and interleukin-1beta were determined by Western blotting and enzyme-linked immunosorbent *** Echocardiogram showed that compared with the Sham group, left ventricular end-systolic diameter and ventricular weight/body weight ratio were significantly higher in the CRF group. Hematoxylin-eosin and Masson staining indicated that myocardial fibers were broken, disordered, and fibrotic in the CRF group. Western blotting, enzyme-linked immunosorbent assay,immunofluorescence and electrophysiological examination suggested that compared with the Sham group, GAP-43 and TNF-α proteins were significantly upregulated, GAP-43 and tyrosine hydroxylase positive nerve fiber area was increased, and ventricular fibrillation threshold was significantly decreased in the CRF group. The above effects were inhibited in the CRF + statin group and the CRF + *** In CRF rats, TNF-α was upregulated, cardiac sympathetic remodeling was more severe, and the nephrogenic cardiac sympathetic remodeling existed. Atorvastatin and etanercept c

关键词： remodeling cardiac inhibited