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Synthesis of High Molecular Weight Polyethylene and E-MA Copolymers Using Iminopyridine Ni(Ⅱ) and Pd(Ⅱ) Complexes Containing a Flexible Backbone and Rigid Axial Substituents

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Chinese Journal of Polymer Science 2023年第2期41卷 233-239页

作者： yu-Dan Liao Qi Cai sheng-yu dai School of Chemical and Environmental Engineering Anhui Polytechnic UniversityWuhu241000China Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei230601China

Suppressing the chain transfer reactions during polymerization in late-transition metal-catalyzed olefin polymerization systems is the key to obtaining high molecular weight polyolefin materials. In this work, two efficient strategies(“sandwich” and rotation-restricted strategies)to retard chain transfer reactions in ethylene(co)polymerization were employed for the iminopyridyl system. Herein, a family of iminopyridyl Ni(Ⅱ)and Pd(Ⅱ) complexes with a flexible backbone and rigid axial bulky aryl substituents were designed, synthesized and characterized. In ethylene polymerization, the iminopyridyl Ni(Ⅱ) and Pd(Ⅱ) catalysts using the two strategies exhibited reasonable activities and generated highly branched polyethylenes with high molecular weights, where catalysts with dibenzosuberyl substituents exhibited significantly higher activities and produced higher molecular weight polyethylene than catalysts with 8-arylnaphthalenyl substituent. A similar trend of activities and molecular weights was also found in the copolymerization of ethylene with MA using the Pd(Ⅱ) catalysts. Moreover, highly branched E-MA copolymers with moderate to high molecular weights and high incorporation ratios(up to 17.4 mol%) were generated with the two Pd(Ⅱ) catalysts. Most interestingly, as compared with the dibenzhydryl Ni(Ⅱ) and Pd(Ⅱ) catalysts, the catalysts using the two strategies exhibited a superior ability to retard the chain transfer reactions and generated polymers and copolymers with 1-2 orders of magnitude higher molecular weights during ethylene(co)polymerization.

关键词： Ni(Ⅱ)and Pd(Ⅱ) Suppressing chain transfer High molecular weight Ethylene(co)polymerization

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Hydnaceous fungi of China 1. Stecchericium （Aphyllophorales）, a genus new to China

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菌物学报 2008年第1期27卷 57-61页

作者： yuAN Hai-sheng dai yu-Cheng Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China

The hydnaceous genus Stecchericium is newly recorded from southeast of China. It is characterized by imbricate basidiocarps, tubular and thick-walled gloeocystidia, and small, ellipsoid, finely asperulate, strongly amyloid basidiospores. An illustrated description of Stecchericium seriatum is given based on the materials collected from yunnan Province.

关键词：中国齿状真菌刺孢齿耳属非褶菌目新记录属

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Two species in Hymenochaetaceae （Basidiomycota） new to China

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菌物学报 2008年第1期27卷 151-155页

作者： yuAN Hai-sheng dai yu-Cheng Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China

1 INTRODUCTION Wood-inhabiting fungi from northern China were investigated extensively during last ten years, and the species in the area are relatively well known (dai 2000; dai et al. 2006, 2007; Wei et al. 2005;

关键词：中国锈革孔菌科新记录新种

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Ultralight and superelastic MXene/reduced graphene oxide aerogels for electromagnetic interference shielding

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Nano Research 2025年第1期18卷 1-9页

作者： Xinfeng Zhou Yang dai Guoyao yue Yiman Zhang Lulu Li Zhong-Zhen yu Peng Min Hao-Bin Zhang 21 State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Advanced Functional Polymer Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Present address:BOE Technology Innovation Center BOE Technology Group Co.Ltd.Beijing 100176China Xi’an Modern Chemistry Research Institute Xi’an 710065China

Lightweight aerogels feature multifunctionality and a high porosity,yet accompanied with poor structure recovery under large strain *** this work,we develop an air bubble-ice crystal dual template and annealing strategy to integrate low density and high resilience for the conductive transition metal carbides/nitrides(MXene)composite *** air bubbles and ice crystals synergistically exclude the nanosheets to the gas-liquid interfaces,thereby constructing unique Y-shaped junctions and robust *** annealing process greatly enhances the interlayer *** external load,the Yshaped structures prevent the stress concentration at the junctions by transferring the forces to the skeleton for maintaining structural *** addition,the wrinkled and thick cell walls,together with the enhanced interlayer interactions,endow the aerogel with exceptional structural stability and *** a result,the MXene/reduced graphene oxide(RGO)composite aerogels exhibit superelasticity with reversible compressive strains of up to 95%.In addition,the electron bridging effect of the RGO sheets affords the aerogel to deliver excellent electromagnetic interference shielding performance,as high as 46.3 dB at 2.5 ***,the remarkable reshapeability of the aerogels allows for precise regulation of structure and performance(33.5-75.1 dB)by a simple wetting compression *** summary,this work offers helpful inspirations for developing lightweight and superelasticity aerogels for extensive applications.

关键词： lightweight superelasticity MXene aerogel electromagnetic interference shielding reshapeability

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用电泳萃取技术回收染料的实验研究

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水处理技术 1999年第5期25卷 288-292页

作者：骆广生吕阳成江伟斌朱慎林戴猷元清华大学化工系北京100084

电泳萃取是一种新型的电泳与萃取技术耦合的分离技术。本文应用这种新型分离技术以正丁醇为萃取剂回收直接耐晒翠兰ＧＬ。在自行设计的连续电泳萃取池内实验研究了电场强度、两相流速等因素对丁醇萃取率及传质通量的影响。实验结果表明... 详细信息

电泳萃取是一种新型的电泳与萃取技术耦合的分离技术。本文应用这种新型分离技术以正丁醇为萃取剂回收直接耐晒翠兰ＧＬ。在自行设计的连续电泳萃取池内实验研究了电场强度、两相流速等因素对丁醇萃取率及传质通量的影响。实验结果表明，电场强度的增大可以有效地提高溶质的萃取率，传质通量也随之增大；水相流速的增大有利于传质通量的增大，而回收率会有所下降；有机相流速的增大，将使萃取率和传质通量同时下降。由回收率的大小可以看出。

关键词：电泳萃取染料废水处理萃取

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Microstructure and mechanical properties of high-strength low alloy steel by wire and arc additive manufacturing

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International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 933-942页

作者： Yi-li dai sheng-fu yu An-guo Huang yu-sheng Shi State Key Laboratory of Material Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China

A high-building multi-directional pipe joint(HBMDPJ)was fabricated by wire and arc additive manufacturing using high-strength low-alloy(HSLA)*** microstructure characteristics and transformation were observed and *** results show that the forming part includes four *** solidification zone solidifies as typical columnar crystals from a molten *** complete austenitizing zone forms from the solidification zone heated to a temperature greater than 1100℃,and the typical columnar crystals in this zone are difficult to *** partial austenitizing zone forms from the completely austenite zone heated between Ac1(austenite transition temperature)and1100℃,which is mainly equiaxed *** several thermal cycles,the partial austenitizing zone transforms to the tempering zone,which consistes of fully equiaxed *** the solidification zone to the tempering zone,the average grain size decreases from 75 to20μ*** mechanical properties of HBMDPJ satisfies the requirement for the intended application.

关键词： wire and arc additive manufacturing high strength low alloy steel microstructure inclusions fine grain ferrite mechanical properties

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原发与继发结核性脓胸手术治疗的早期临床观察

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中国防痨杂志 2017年第3期39卷 312-314页

作者：蒋钰辉刘小玉盛健戴希勇武汉市肺科医院武汉市结核病防治所外科 430030

为比较原发结核性脓胸与继发结核性脓胸的手术风险及术后早期治疗效果,本研究选取武汉市肺科医院外科2014年11月至2016年10月收治的慢性结核性脓胸行纤维板剥脱术的患者60例,按其病因分为原发组和继发组,原发组32例,继发组28例,对两组... 详细信息

为比较原发结核性脓胸与继发结核性脓胸的手术风险及术后早期治疗效果,本研究选取武汉市肺科医院外科2014年11月至2016年10月收治的慢性结核性脓胸行纤维板剥脱术的患者60例,按其病因分为原发组和继发组,原发组32例,继发组28例,对两组患者的手术时间、术中出血量、术后带管时间、术后1个月肺完全复张率进行比较.结果显示,原发组的手术时间为（190.63±67.06） min,术中失血量为（255.34±61.72） ml,术后带管时间为（7.03±2.34）d,均少于继发组[分别为（301.07±81.29） min、（504.39±115.56） ml、（14.37±4.03）d],差异均有统计学意义（t值分别为5.77、4.33、3.85,P值均＜0.01）;原发组术后1个月肺完全复张率为90.6％（29/32）,明显高于继发组（17.9％,5/28）,差异有统计学意义（x2=32.20,P＜0.01）.作者认为,相对于原发结核性脓胸,继发结核性脓胸手术治疗的难度大、风险高、早期恢复差;术前可以通过结核性脓胸分型对手术的风险和预后进行评估,以做好充分的术前准备工作.

关键词：脓胸,结核性外科手术治疗,临床研究性

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Gauges for the Cookie-cutter Sets

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Acta Mathematica Sinica,English Series 2009年第12期25卷 2119-2126页

作者： yu Xia dai sheng You WEN Department of Mathematics Hubei University Wuhan 430062 P. R. China

Let E be a cookie-cutter set with dimH E =s. It is known that the Hausdorff s-measure and the packing s-measure of the set E are positive and finite. In this paper, we prove that for a gauge function g the set E has positive and finite Hausdorff g-measure if and only if 0 〈 liminft→0 g（t）/ts 〈 ∞. Also, we prove that for a doubling gauge function g the set E has positive and finite packing g-measure if and only if 0 〈 lim supt→0 g（t）/ts 〈 ∞.

关键词： cookie-cutter set gauge function Hausdorff gauge packing gauge

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Near-infrared brain functional characteristics of mild cognitive impairment with sleep disorders

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World Journal of Psychiatry 2025年第1期15卷 106-116页

作者： Heng Liao Sha Liao yu-Jiao Gao Xi Wang Li-Hong Guo Su Zheng Wu Yang Yi-Nan dai Sleep Psychosomatic Medicine Center Taihe Hospital of Shiyan CityAffiliated Hospital of Hubei University of MedicineShiyan 442000Hubei ProvinceChina Department of Integrated Chinese and Western Medicine Taihe Hospital of Shiyan CityAffiliated Hospital of Hubei University of MedicineShiyan 442000Hubei ProvinceChina Department of Orthopaedics Taihe Hospital of Shiyan CityAffiliated Hospital of Hubei University of MedicineShiyan 442000Hubei ProvinceChina Department of Rehabilitation Taihe Hospital of Shiyan CityAffiliated Hospital of Hubei University of MedicineShiyan 442000Hubei ProvinceChina

BACKGROUND Mild cognitive impairment(MCI)has a high risk of progression to Alzheimer’s *** disease is often accompanied by sleep disorders,and whether sleep disorders have an effect on brain function in patients with MCI is *** To explore the near-infrared brain function characteristics of MCI with sleep *** A total of 120 patients with MCI(MCI group)and 50 healthy subjects(control group)were *** subjects underwent the functional near-infrared spec-troscopy *** baseline data,Mini-Mental State Examination,Montreal Cognitive Assessment scale,fatigue severity scale(FSS)score,sleep parameter,and oxyhemoglobin(Oxy-Hb)concentration and peak time of functional near-infrared spectroscopy test during the task *** relationship between Oxy-RESULTS Compared with the control group,the FSS score of the MCI group was higher(t=11.310),and the scores of Pittsburgh sleep quality index,sleep time,sleep efficiency,nocturnal sleep disturbance,and daytime dysfunction were higher(Z=-10.518,-10.368,-9.035,-10.661,-10.088).Subjective sleep quality and total sleep time scores were lower(Z=-11.592,-9.924).The sleep efficiency of the MCI group was lower,and the awakening frequency,rem sleep latency period,total sleep time,and oxygen desaturation index were higher(t=5.969,5.829,2.887,3.003,5.937).The Oxy-Hb concentration at T0,T1,and T2 in the MCI group was lower(t=14.940,11.280,5.721),and the peak time was higher(t=18.800,13.350,9.827).In MCI patients,the concentration of Oxy-Hb during T0 was negatively correlated with the scores of Pittsburgh sleep quality index,sleep time,total sleep time,and sleep efficiency(r=-0.611,-0.388,-0.563,-0.356).It was positively correlated with sleep efficiency and total sleep time(r=0.754,0.650),and negatively correlated with oxygen desaturation index(r=-0.561)and FSS score(r=-0.526).All comparisons were P<*** Patients with MCI and sleep disorders have lower near-infrared brain function than norm

关键词： Mild Cognitive impairment Sleep disorders Near-infrared Brain functional Characteristics

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Further Notes on the Gaussian Beam Expansion

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Chinese Physics Letters 2012年第2期29卷 116-118页

作者： dai yu-Rong DING De-sheng Department of Physics Southeast UniversityNanjing 210096 School of Electronic Science and Engineering Southeast UniversityNanjing 210096 Laboratory of Modern Acoustics of MOE Nanjing UniversityNanjing 210093

We provide alternatively a simple way of computing the Fresnel field integral,a further extension to the Gaussianbeam *** a known result that the circ function is approximately decomposed into a sum of Gaussian functions,the zero-order Bessel function of the first kind is similarly expanded by the Bessel-Fourior *** expansions are together inserted in this integral,which is then expressible in terms of the simple algebraic *** approach is useful in treatment of the field radiation problem for a large and important group of piston sources in *** examples,the calculation results for the uniform and the simply supported piston sources are presented,in a good agreement with those evaluated by numerical integration.

关键词： functions Gaussian Bessel

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