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Cardiology Discovery 2023年第1期3卷 54-59页

作者： Xiaofeng He Lei Zhang Xuanze Liu Xiaozeng Wang The Department of Cardiology General Hospital of Northern Theater CommandShenyangLiaoning 110016China

A 43-year-old male was admitted to General Hospital of Northern Theater Command with exacerbation of chest pain for 10 d.Computed tomographic angiography(CTA)showed an irregular aortic arch aneurysm involving the left subclavian artery(LSA),with penetrating aortic ulcer and intramural hematoma.A modified fenestrated thoracic endovascular aortic repair(TEVAR)technique was performed successfully.Follow-up CTA showed that stent grafts were well-apposed,without endoleaks,migration,or branch artery occlusion,and the hematoma was almost completely absorbed.In this case,precise fenestrations were created by measurements based on three-dimensional CT reconstruction and angiography.Furthermore,the physician chose an LSA approach to catch the guide wire and deployed branched stent grafts,considering the oblique direction of this branch and the small size of the fenestration.This case shows that pre-fenestrated and inner bare stent enhancing TEVAR is a safe and feasible technique for repair of complicated aortic arch aneurysm.

关键词： Aortic aneurysm Aortic arch Thoracic endovascular aortic repair Pre-fenestrated stent graft branched stent graft Case report

Cobalt Sulfide Confined in N-Doped Porous branched Carbon Nanotubes for Lithium-Ion Batteries

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Nano-Micro Letters 2019年第2期11卷 157-165页

作者： Yongsheng Zhou Yingchun Zhu Bingshe Xu Xueji Zhang Khalid A.Al.Ghanim Shahid Mahboob College of Chemistry and Materials Engineering Anhui Science and Technology UniversityBengbu 233030People’s Republic of China Key Laboratory of Inorganic Coating Materials CAS Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024People’s Republic of China Beijing Key Laboratory for Bioengineering and Sensing Technology Research Center for Bioengineering and Sensing TechnologySchool of Chemistry and BioengineeringUniversity of Science and Technology Beijing30 Xueyuan RoadHaidian DistrictBeijing 100083People’s Republic of China Department of Zoology College of ScienceKing Saud UniversityRiyadhSaudi Arabia Department of Zoology GC UniversityFaisalabadPakistan

Lithium-ion batteries(LIBs) are considered new generation of large-scale energy-storage devices.However,LIBs suffer from a lack of desirable anode materials with excellent specific capacity and cycling stability.In this work,we design a novel hierarchical structure constructed by encapsulating cobalt sulfide nanowires within nitrogen-doped porous branched carbon nanotubes(NBNTs)for LIBs.The unique hierarchical Co9S8@NBNT electrode displayed a reversible specific capacity of 1310 mAhg-1 at a current density of 0.1 Ag-1,and was able to maintain a stable reversible discharge capacity of 1109 mAhg-1 at a current density of 0.5 Ag-1 with coulombic efficiency reaching almost 100% for 200 cycles.The excellent rate and cycling capabilities can be ascribed to the hierarchical porosity of the one-dimensional Co9S8@NBNT internetworks,the incorporation of nitrogen doping,and the carbon nanotube confinement of the active cobalt sulfide nanowires offering a proximate electron pathway for the isolated nanoparticles and shielding of the cobalt sulfide nanowires from pulverization over long cycling periods.

关键词： Lithium-ion batteries Nitrogen doping Cobalt sulfide branched carbon nanotubes

Numerical simulations of the bi-level and branched structure of intracloud lightning flashes

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Science China Earth Sciences 2006年第6期49卷 661-672页

作者： TAN Yongbo1, TAO Shanchang1, ZHU Baoyou1, MA Ming2 & LU Weitao2 1. School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China 2. Chinese Academy of Meteorological Sciences, Beijing 100081, China School of Earth and Space Sciences University of Science and Technology of China Hefei China Chinese Academy of Meteorological Sciences Beijing China

Intracloud (IC) lightning flashes have been simulated in fine resolution (12.5 m) by using a bidirectional stochastic lightning parameterization scheme within 2-dimensional domain. The simu-lated results show that the IC flashes have a bilevel channel structure and the altitudes of the hori-zontal channels are at the same heights of potential wells, which are supported by the previous VHF source observations and balloon soundings of electric field profile in the thundercloud. Further con-clusions are: (1) After an IC flash is initiated near the boundary between positve and nagetive charge zone, the negative (or positive) leader tends to propagate into the positive (or negative) charge zone. Both types of positive and negative IC flashes have been reproduced and their polarity depends on the up and down disposition of the positive and negative charge regions. (2) The extension range of leaders is correlative with the cloud charge distribution. The leader is possible to extend through the inverted charge region all over where it is extending, but keeps away from the isolated charge area of the same polarity. (3) The channel structures also depend on the electric potential distributions in the thundercloud. Before propagating into the central area of potential wells, the leader tends to extend along the direction with the maximum of potential gradient. Once extending away from the center of potential wells, the leader tends to extend along the direction with the slowest potential change. (4) The IC flash channels have the fractal feature with fractal dimension 1.45 before leaders pass through the central area of charge regions. The exponent decreases rapidly once leaders extend into the low-density charge regions. (5) The induced charges of opposite polarity are deposited in the leader channels within preexisting positive and negative charge regions during IC flash discharges. This causes a new and complicated charge distribution in the thundercloud, and the potential extremum drops from 200 to 20 Mv when the IC fla

关键词： IC, lightning parameterization, branched bilevel structure, fractal feature, propagation tendency.

Facile synthesis of dendrimer-like star-branched poly(isopropylacrylamide) via combination of click chemistry and atom transfer radical polymerization

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Science China Chemistry 2010年第12期53卷 2520-2527页

作者： WAN XueJuan,XU Jian & LIU ShiYong CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering,Hefei National Laboratory for Physical Sciences at the Microscale,University of Science and Technology of China,Hefei 230026,China CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China Hefei China

We report a facile synthesis method of dendrimer-like star-branched poly(N-isopropylacrylamide) (PNIPAM) via the combination of click chemistry and atom transfer radical polymerization (ATRP) by employing the arm-first approach.First,the α-azido-ω-chloro-heterodifunctionalized building block,N3-PNIPAM-Cl (G0-Cl),was synthesized via ATRP by 3-azidopropyl 2-chloropropionate as the initiator.Taking advantage of click chemistry,the first generation (G1) of dendrimer-like star-branched PNIPAM,G1-(Cl)3,was facilely prepared via the click coupling reaction between G0-Cl and tripropargylamine.For the construction of second generation (G2) dendrimer-like star-branched PNIPAM,G2-(Cl)6,terminal chloride moieties of G1-(Cl)3 were first converted to azide,and then reacted with excess tripropargylamine to give G1-(alkynyl)6 ;G2-(Cl)6 was subsequently prepared via click reaction between G1-(alkynyl) 6 and G0-Cl.Gel permeation chromatography (GPC) and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry were employed to confirm the successful construction of dendrimer-like star-branched polymers.The unique thermal phase transition behavior of this dendrimer-like star-branched polymer in aqueous solutions was further investigated by turbidimetry and micro-differential scanning calorimetry (Micro-DSC).

关键词： dendrimer-like branched ATRP click chemistry

Novel　Highly　branched　Polyester　Nanoparticles(I)──Light-Scattering　Characterization

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Chemical Research in Chinese Universities 1998年第1期14卷 70-75页

作者： Ma, Rong-jiu Wu, Qi Jilin Univ Inst Polymer Changchun 130023 Peoples R China Chinese Univ Hong Kong Dept Chem Shatin NT Peoples R China

ＮｏｖｅｌＨｉｇｈｌｙＢｒａｎｃｈｅｄＰｏｌｙｅｓｔｅｒＮａｎｏｐａｒｔｉｃｌｅｓ（Ｉ）──Ｌｉｇｈｔ－ＳｃａｔｔｅｒｉｎｇＣｈａｒａｃｔｅｒｉｚａｔｉｏｎＭＡＲｏｎｇ－Ｊｉｕ（ＰｏｌｙｍｅｒＩｎｓｔｉｔｕｔｅ，Ｊｉ... 详细信息

ＮｏｖｅｌＨｉｇｈｌｙＢｒａｎｃｈｅｄＰｏｌｙｅｓｔｅｒＮａｎｏｐａｒｔｉｃｌｅｓ（Ｉ）──Ｌｉｇｈｔ－ＳｃａｔｔｅｒｉｎｇＣｈａｒａｃｔｅｒｉｚａｔｉｏｎＭＡＲｏｎｇ－Ｊｉｕ（ＰｏｌｙｍｅｒＩｎｓｔｉｔｕｔｅ，ＪｉｌｉｎＵｎｉｖｅｒｓｉｔｙ，Ｃｈａ...

关键词： branched Nanoparticles Novel Polyester Highly

Design and synthesis of the novel branched fluorinated surfactant intermediates with CF_3CF_2CF_2C(CF_3)_2 group

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Chinese Chemical Letters 2019年第3期30卷 566-568页

作者： Ding Zhang Min Sha Renming Pan Xiangyang Lin Ping Xing Biao Jiang School of Chemical Engineering Nanjing University of Science and Technology CAS Key Laboratory of Synthetic Chemistry of Natural Substances Shanghai Institute of Organic Chemistry Chinese Academy of Sciences School of Management Science & Engineering Nanjing University of Finance & Economics

Perfluorooctanoic acid(PFOA) or perfluorooctane sulphonate(PFOS) was one of the most prominent fluorosurfactants and applied widely in firefighting and daily chemical, etc. However, these surfactants have recently been identified as toxic and undegradability in the environment. Developing an efficient approach to environment-friendly fluorosurfactants is essential. A fluorocarbon branched chain strategy was adopted to develop/PFOS substitutes. A series of intermediates of novel branched fluorinated surfactants with CF_3 CF_2CF_2C(CF3)_2 group were synthesized from perfluoro-2-methyl-2-pentene. All the steps were mild, easy-handled and cheap. It is expected to be a very significant direction for the development of non-bioaccumulable alternatives of PFOA or PFOS.

关键词： Perfluoro-2-methyl-2-pentene branched fluorinated surfactants Oxy fluorocarbon chain

Growth and Formation Mechanism of branched Carbon Nanotubes by Pyrolysis of Iron(Ⅱ) Phthalocyanine

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Nano-Micro Letters 2013年第2期5卷 124-128页

作者： Qiong Wei Yunyun Liu Lijie Zhang Shaoming Huang Nanomaterials and Chemistry Key Laboratory College of Chemistry and Materials Engineering Wenzhou University

In this letter, a route for synthesizing vertically aligned multi-walled carbon nanotubes（MWCNTs） with branched nanotubes in large area was reported. The branched MWCNTs up to about 30% can be generated by the pyrolysis of iron（Ⅱ） phthalocyanine in presence of thiol under Ar/H2 at 800900℃. The growth mechanism of the branched nanotubes was proposed and the possible reason that thiol enhanced branched nanotubes growth is discussed. The as-prepared samples provide a suitable candidate to investigate the special electrical or thermal properties of CNTs with branched structures further.

关键词： Carbon nanotube Chemical vapour deposition branched Growth mechanism

COMPARISON OF GPC AND THERMAL FIELDFLOW FRACTIONATION METHODS FOR LINEAR AND STAR branched POLYSTYRENE SAMPLES

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高分子科学(英文版) 1985年第3期3卷 265-271页

作者：高玉书汪健沈家(马总) Institute of Chemistry Academia Sinica Beijing Department of Chemistry Jilin University Changchun Changchun

The Thermal Field-Flow Fractionation (TFFF) method was used to determine the elution volumeof a series of star branched polystyrene having different number of arms but the same arm molecularweigh and polystyrene standards with narrow distribution whose molecular weight ranged from5.0×10~4 to 8.6×10~5. Results were obtained by measuring at two temperature difference (△T=30℃and △T=50℃in THF. The same star branched samples were measured by means of GPC method.Comparison of Vr-Mrelationships obtained from TFFF and GPC showed that the displacement of V_r-M curves for star and linear polystyrene is larger than that in GPC. This difference is caused by theentirely different mechanism of separation for these two methods. As the controlling factor is hy-drodynamic volume of the polymer chain in solution for GPC, it is the diffusion coefficient of polymermolecules for TFFF. The experimental results indicate that the influence of variance of chain struc-ture on diffusion coefficient is stronger than that on the hydrodynamic volume and that TFFF tech-nique may be used as a method for characterizing branching of polymer molecules. For this pur-pose a proper theoretical model and more accurate experiments are needed.

关键词： polystyrene struc branching branched narrow hydrodynamic solute retention ranged characterizing

Toughening of Poly (L-lactide) with branched Multiblock Poly (ε-caprolactone)/poly (D-lactide) Copolymers

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Journal of Donghua University(English Edition) 2018年第5期35卷 365-372页

作者：常悦陈支泽杨一奇 College of Chemistry Chemical Engineering and BiotechnologyDonghua University Department of Textiles Merchandising and Fashion DesignUniversity of Nebraska-Lincoln Department of Biological Systems Engineering and Nebraska Center for Materials and Nanoscience University of Nebraska-Lincoln

A total biodegradable elastomer,branched multiblock poly( ε-caprolactone)/poly( D-lactide)( BMCD) was prepared using 3-isocyanatopropyltriethoxysilane( IPTS) as a coupling agent.To improve the toughness of poly( L-lactide)( PLLA),PLLA/BMCD blends were prepared via a simple solvent evaporation method at various BMCD loadings. Tensile test showed that the elongation at break of PLLA blends increased to 50. 97% and104. 55% at the loadings of 5% and 7%( mass fraction) BMCD respectively, with no sacrifice of their biodegradability. This approach allowed for simultaneous control of mechanical and biodegradable properties of PLLA with a few additives in actual production. Furthermore, UV-VIS test showed that the light transmittance of the films at the loadings of 5%( mass fraction)BMCD was almost the same as pure PLLA at 400 nm.

关键词： poly(L-lactide)(PLLA) branched polymer toughness transparency stereocomplex

Water-to-air transfer of branched and linear PFOA:Influence of pH,concentration and water type

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Emerging Contaminants 2017年第1期3卷 46-53页

作者： Jana H.Johansson Hong Yan Urs Berger Ian T.Cousins Department of Environmental Science and Analytical Chemistry(ACES) Stockholm UniversitySvante Arrhenius v€ag 811418 StockholmSweden State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghaiChina Department Analytical Chemistry Helmholtz Centre for Environmental Research e UFZLeipzigGermany

The volatilisation of perfluorooctanoic acid(PFOA)was measured experimentally at a range of pH values using a previously published laboratory method.Water-to-air transfer was studied for five structural isomers,namely:the linear isomer(n-PFOA)and the four most commonly occurring branched isomers(3-,4-,5-and 6-PFOA).The influence of water concentration and water type on the pH-dependent waterto-air transfer was also investigated for n-PFOA.The water-to-air transfer was studied over the course of 48 h at pH values ranging from 0.2 to 5.5.Under all experimental conditions tested,the volatilisation of PFOA was negligible at pH>2.5.In experiments performed with MilliQ water,volatilisation increased with decreasing water pH.In experiments performed with tap water and lake water,maximum volatilisation was observed at pH 1.The concentration of PFOA in water had no influence on the pH value at which water-to-air transfer was observed(i.***.at pHbranched isomers at low pH,volatilisation was not observed above pH 2.5 for any branched isomer suggesting that all PFOA isomers have a low pKa.Overall,these laboratory results demonstrate that volatilisation of any structural isomer of PFOA from water is negligible at environmentally-relevant conditions.It is unlikely that PFOA isomers will be fractionated in the environment as a result of volatilisation because it is a process of negligible environmental relevance.

关键词： PFOA Isomer branched Acid dissociation pKa