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Facile Synthesis of Polycarbonate Diol via Copolymerization of CO_(2) and Cyclohexene Oxide Catalysed by a Combination of One-Component Phosphonium Borane Lewis Pair and Water

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Chinese Journal of Polymer Science 2023年第5期41卷 735-744,I0009页

作者： Xiao-Wu Wang ji-wen hui Yu-Tao Li Yan-Ru Gu Zhi-Bo Li State Key Laboratory Base of Eco-Chemical Engineering/College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China Key Laboratory of Biobased Polymer Materials Shandong Provincial Education Department/School of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao 266042China

Well-defined polycarbonate diol was successfully synthesized through a strategy using a combination of organocatalyst and *** strategy was less developed in organocatalyzed polymerization and frequently regarded as side ***,one-component phosphonium borane Lewis pairs PB1-PB8 were successfully applied in the copolymerization of CO_(2) and cyclohexene oxide(CHO)to generate poly(CHO-alt-CO_(2))carbonate(PCHC).Parameters of linker length and counter anion effects on the catalyst activity were *** was found that Lewis pair PB3 served as a dual initiator and catalyst in the copolymerization of CHO and CO_(2) with or without the presence of *** contrast,Lewis pair PB8 can serve as a true catalyst for the preparation of well-definedα,ω-hydroxyl PCHC *** was achieved by introducing a labile CF3COO group as counter anion through anion exchange reaction while water molecules acted as chain transfer *** function of trifluoroacetate group in the polymerization process was investigated in detail and possible mechanism was *** changing the amount of water and catalyst loading,PCHC diols with varied molecular weight(1.5 kg/mol to 7.5 kg/mol),low dispersities(D99%)could be easily *** low molecular weight PCHC diol was used as a bifunctional macroinitiator for the ring-opening polymerization of L-lactide(LLA)to afford ABA triblock copolymer in one-pot synthesis.

关键词： Polycarbonate Phosphonium borane Lewis pair CO_(2)utilization Organocatalysis Ring-opening polymerization

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Effects of silicon amendment on the occurrence of rice insect pests and diseases in a field test

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Journal of Integrative Agriculture 2018年第10期17卷 2172-2181页

作者： HAN Yong-qiang wen ji-hui PENG Zhao-pu ZHANG De-yong HOU Mao-lin Institute of Plant Protection Hunan Academy of Agricultural Sciences Changsha 410125 P.R.China State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing 100193 P.R.China Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China Changsha 410128 P.R. China

Rice is one of the most important staple foods for the world population,but it is attacked by a number of destructive *** evidence from greenhouse and laboratory tests has shown that silicon（Si）amendment can confer enhanced resistance to pests in rice,few studies have directly demonstrated the Si-mediated protection from pests in a field *** this study,field plots with silicon amendments at 0,75,150 and 300 kg SiO2 ha-1 in early-and late-season rice were employed to evaluate the effects of silicon amendment on the occurrence of major insect pests and diseases and rice *** with the control plots without silicon amendment,plant damage by stem borer and leaf folder and population size of planthopper were significantly lower in three to five of the seven monitoring observations in each season in the plots amended with 300 kg SiO2 *** disease index of rice blast in the early-season rice was lower in the plots amended with Si at 300 kg SiO2 ha-1 than in the control plots,while Si protection from rice blast in the late-season rice and from rice sheath blight in the early-season rice were not *** insignificant increase of rice yield by 16.4%（604 kg ha-1）was observed in the plots amended with 300 kg SiO2 ha-1 over the control *** results indicate that Si amendment at 300kg SiO2 ha-1 can provide substantial protection from some of the rice pests under field *** findings support the recommendation of silicon amendment as a key component of integrated management of rice pests.

关键词： silicon rice insect pest disease yield plant resistance

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Multifunctional carbon materials from rugose rose for energy storage and water purification

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 1-13页

作者： Peng-hui Li hui Zhou wen-Juan Wu jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources Nanjing Forestry UniversityNanjing 210037China College of Light Industry and Food Engineering Nanjing Forestry UniversityNanjing 210037China College of Chemical Engineering East China University of Science and TechnologyShanghai 200237China State Key Laboratory of Chemical Engineering Shanghai 200237China

With the advancement of social process,the resource problem is becoming more prominent,biomass materials come into being,and it is becoming more and more important to explore and prepare efficient and multifunctional biomass materials to alleviate the problems of energy storage and water *** this paper,nitrogen-doped hierarchical porous carbon materials(NRRC)were produced by one-step carbonization of withered rose as raw material and melamine as nitrogen source with KOH-activated *** resulting nitrogen-doped porous carbon material had the most abundant pores and the best microspherical graded pore structure,with a specific surface area of up to 1393 m2·g^(-1),a pore volume of 0.68 cm3·g^(-1),and a nitrogen-doped content of 5.52%.Electrochemical tests showed that the maximum specific capacitance of NRRC in the three-electrode system was 346.4 F·g^(-1)(0.5 A·g^(-1)),which was combined with favorable capacitance retention performance and cycling *** NRRC//NRRC symmetric supercapacitors were further assembled,and the maximum energy density of a single device was 23.88 Wh·kg^(-1),which still maintains excellent capacitance retention and cyclic charging/discharging *** example,the capacitance retention rate was always close to 96.27%with almost negligible capacitance loss after 10000 consecutive charge/discharge cycles(current density:10 A·g^(-1)).Regardless of the three-electrode or two-electrode system,the super capacitive performance of NRRC porous carbon materials was comparable to the electrochemical performance of many reported biomass porous carbon materials,which showed better energy storage advantages and practical application *** addition,NRRC porous carbon materials had excellent water purification *** dye adsorption test confirmed that NRRC had a high adsorption capacity(491.47 mg·g^(-1))for methylene *** undoubtedly also showed a potential and promising avenue for high value-added utilization

关键词： rose carbon adsorption electrode material electrochemical performance

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Data-Driven Design for Targeted Regulation of Heat Transfer in Carbon/Carbon Composite Structure

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Journal of Thermal Science 2024年第2期33卷 648-657页

作者： XIAO Heye WANG Zelin WANG hui ji Ritian Unmanned System Research Institute Northwestern Polytechnical UniversityXi’an710072China School of Aeronautics Northwestern Polytechnical UniversityXi’an710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518063China MOE Key Laboratory of Thermo-Fluid Science and Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an710049China

Targeted regulation of heat transfer in carbon/carbon composite structure is built for cooling electronic device.A three-dimensional data-driven design model coupling genetic algorithm(GA) with self-adaption deep learning for targeted regulation of heat transfer in built structure is *** self-adaption deep learning model predicts the temperature of built structure closer to optimal value in GA *** distributions of pore and carbon fiber bundles in built structure are optimized by the proposed *** surface temperature of electronic device in the optimized structures is 19.1%-27.5% lower than that in the initial configurations when the porosity of built structure varies from 3% to 11%.The surface temperature of electronic device increases with an increase in *** built structure with carbon fiber bundles near the surface of electronic device and pore distribution in the middle of structure has a higher heat dissipation capacity compared with that in the initial ***,the computation time of the proposed model is less than one tenth compared with that of the traditional genetic algorithm.

关键词： targeted regulation of heat transfer self-adaption deep learning genetic algorithm carbon/carbon composite structure

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Noninvasive beam diagnosis based on the TM_(010)mode

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Nuclear Science and Techniques 2024年第7期35卷 115-125页

作者： Chuang-Ye Song wen-hui Huang Department of Engineering Physics Tsinghua University BeijingBeijing100084China of Education Beijing100084China

A resonant cavity based on the TM_(010)mode is an effective tool for noninvasive beam characterization. This technique has the advantages of a high signal-to-noise ratio, compact structure, and is related to multiple parameters compared with other beam monitors. In this study, high-precision measurements of the bunch charge, arrival time, bunch length, and energy parameters based on the TM_(010)mode are discussed. A cavity beam arrival time monitor(BAM) utilizing a phase cavity has been widely used in many facilities. Regarding bunch-length measurements, the influence of the beam energy, beam offset,and longitudinal spectrum on the TM_(010)mode are carefully considered to reduce errors, and the theoretical resolution of two cavities with different frequencies is analyzed. Owing to the dependence of the beam velocity of the beam loss factor, this method can also be used for the detection low beam energy using two cavities with the same frequency but different cavity lengths. A set of three cavities with different lengths and frequencies of 1.902 and 11.424 GHz is presented for measuring the four aforementioned parameters.

关键词： TM_(010)mode Noninvasive diagnosis Beam length Low energy

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Study on a conical bearing for acceleration-sensitive equipment

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 103-128页

作者： Pang hui Xu wen Dai Junwu jiang Tao Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin 150080China School of Civil Engineering and Transportation Beihua UniversityJilin 132013China

Seismic isolation effectively reduces seismic demands on building structures by isolating the superstructure from ground vibrations during ***,isolation strategies give less attention to acceleration-sensitive systems or ***,as the isolation layer’s displacement grows,the stiffness and frequency of traditional rolling and sliding isolation bearings increases,potentially causing self-centering and resonance *** a result,a new conical pendulum bearing has been selected for acceleration-sensitive equipment to increase self-centering capacity,and additional viscous dampers are incorporated to enhance system ***,the theoretical formula for conical pendulum bearings is supplied to analyze the device’s dynamic parameters,and shake table experiments are used to determine the proposed device’s isolation efficiency under various *** to the test results,the newly proposed devices have remarkable isolation performance in terms of minimizing both acceleration and displacement ***,a numerical model of the isolation system is provided for further research,and the accuracy is demonstrated by the aforementioned experiments.

关键词： seismic isolation acceleration-sensitive equipment the conical pendulum bearing shake table tests isolation performance,numerical model

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Local Hamilton type Gradient Estimates and Harnack Inequalities for Nonlinear Parabolic Equations on Riemannian Manifolds

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 539-546页

作者： wen WANG Da-peng XIE hui ZHOU School of Mathematics and Statistics Hefei Normal UniversityHefei 230601China

In this paper,we prove a local Hamilton type gradient estimate for positive solution of the nonlinear parabolic equation ut(x,t)=Δu(x,t)+au(x,t) ln u(x,t)+bu^(α)(x,t),on M×(-∞,∞) with α∈R,where a and b are *** ... 详细信息

关键词： nonlinear parabolic equation gradient estimate Harnack inequality

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Clinical study on the relationship between liver cirrhosis,ascites,and hyponatremia

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 751-758页

作者： Xuan-ji Li hui-hui Meng Department of Gastroenterology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina Department of Hepatology Hubei Provincial Hospital of Traditional Chinese MedicineWuhan 430065Hubei ProvinceChina

BACKGROUND Cirrhosis is a common liver disease,and ascites is one of the common clinical ***,the clinical manifestations of ascites combined with hyponatremia as a high-risk condition and its relationship to patient prognosis have not been fully *** To explore the clinical manifestations,prognostic factors,and relationships of ascites with hyponatremia in patients with cirrhosis to provide better diagnostic and treatment *** In this study,we retrospectively analyzed the clinical data of 150 patients diagnosed with cirrhosis and ascites between 2017 and *** were divided into two groups:ascites combined with hyponatremia group and ascites *** compared the general characteristics,degree of hyponatremia,complications,treatment,and prognosis between the two *** In the study results,patients in the ascites combined with hyponatremia group showed an older average age(58.2±8.9 years),64.4%were male,and had a significantly longer hospitalization time(12.7±5.3 d).Hyponatremia was more severe in this group,with a mean serum sodium concentration of 128.5±4.3 mmol/L,which was significantly different from the ascites group of 137.6±2.1 mmol/*** with ascites and hyponatremia were more likely to develop hepatic encephalopathy(56.2%vs 39.0%),renal impairment(45.2%vs 28.6%)and infection(37.0%vs 23.4%).Regarding treatment,this group more frequently used diuretics(80.8%vs 62.3%)and salt supplements(60.3%vs 38.9%).Multiple logistic regression analysis identified older age[Odds ratio(OR)=1.06,P=0.025]and male gender(OR=1.72,P=0.020)as risk factors for hyponatremia combined with ***,patients with ascites and hyponatremia present a clear high-risk status,accompanied by severe complications and poor *** In patients with cirrhosis,ascites with hyponatremia is a high-risk condition that is often associated with severe complications.

关键词： Liver cirrhosis Ascites Hyponatremia Risk Complications

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Influence of Incomplete Soil Plugs on Bearing Capacities of Bucket Foundations in Clay

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China Ocean Engineering 2024年第1期38卷 144-155页

作者： LI hui-shan LIU Run YANG Xu LIAN ji-jian State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China Institute of Marine Energy and Intelligent Construction Tianjin University of TechnologyTianjin 300384China

Due to the uneven seabed and heaving of soil during pumping,incomplete soil plugs may occur during the installation of bucket foundations,and the impacts on the bearing capacities of bucket foundations need to be *** this paper,the contact ratio(the ratio of the top diameter of the soil plug to the diameter of the bucket)and the soil plug ratio(the ratio of the soil heave height to the skirt height)are defined to describe the shape and size of the incomplete soil ***,finite element models are established to investigate the bearing capacities of bucket foundations with incomplete soil plugs and the influences of the contact ratios,and the soil plug ratios on the bearing capacities are *** results show that the vertical bearing capacity of bucket foundations in homogeneous soil continuously improves with the increase of the contact ***,in normally consolidated soil,the vertical bearing capacity barely changes when the contact ratio is smaller than 0.75,while the bearing capacity suddenly increases when the contact ratio increases to 1 due to the change of failure *** contact ratio hardly affects the horizontal bearing capacity of bucket ***,the moment bearing capacity improves with the increase of the contact ratio for small aspect ratios,but hardly varies with increasing contact ratio for aspect ratios larger than ***,the reduction coefficient method is proposed based on this analysis to calculate the bearing capacities of bucket foundations considering the influence of incomplete soil *** comparison results show that the proposed reduction coefficient method can be used to evaluate the influences of incomplete soil plug on the bearing capacities of bucket foundations.

关键词： bucket foundation incomplete soil plug uniaxial bearing capacity contact ratio soil plug ratio

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Effects of surface morphology on tribological properties of Arapaima gigas scales

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Friction 2024年第7期12卷 1469-1482页

作者： Shuaijun ZHANG Pengpeng BAI Xiangli wen Chengwei wen hui CAO Wanyou YANG Yu TIAN State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Bionic Engineering(Ministry of Education China)Jilin UniversityChangchun 130022China

The remarkable mechanical adaptability of arapaima(Arapaima gigas)scales has made them an important subject of ***,no research has been conducted into their tribological properties,which are crucial for the protectability and flexibility of *** this study,by combining morphological characterizations,friction experiments,and theoretical analyses,the relationship between the surface morphology and tribological properties of arapaima scales is *** results indicate that arapaima scales exhibit varying surface morphologies in different *** specifically,the exposed regions of scales feature grooves and a circulus,whereas the covered regions exhibit *** specific surface morphology of arapaima scales produces varying tribological properties across different regions and sliding *** unique tribological properties of arapaima scales influence the forces received from predator attacks and neighboring scales,directly influencing the arapaima’s protective *** study provides new insights into the mechanisms of natural flexible dermal armors,and it has potential applications in personal protective systems.

关键词： arapaima scales surface morphology tribological properties protectability

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