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Conservative pulp treatment for Oehlers type Ⅲ dens invaginatus: A case report

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World Journal of Clinical Cases 2019年第18期7卷 2823-2830页

作者： hui-Na Lee Yuk-Kwan Chen Cheng-hui Chen Chun-Yin Huang Ying-hui su Ying-Wei Huang Fu-Hsiung Chuang Division of Conservative Dentistry Dental DepartmentKaohsiung Medical University Chung-Ho Memorial HospitalKaohsiung 80756Taiwan Dental Department Kaohsiung Municipal CiJin HospitalKaohsiung 80756Taiwan Division of Oral Pathology and Radiology Dental DepartmentKaohsiung Medical University Chung-Ho Memorial HospitalKaohsiung 80756Taiwan School of Dentistry Kaohsiung Medical UniversityKaohsiung 80756Taiwan Oral and Maxillofacial Radiology Center Kaohsiung Medical UniversityKaohsiung 80756Taiwan Department of Nuclear Medicine E-DA HospitalKaohsiung 80756Taiwan Dental Department Kaohsiung Municipal Hsiao Kang HospitalKaohsiung 80756Taiwan

BACKGROUND Diverse presentations of dens invaginatus (DI) and root canal treatment with an immature open apex often pose challenges to dentists. Adequate treatment planning for DI is the main reason for successful approach, i.e., we should consider the shape and depth of the concave folding, the condition of the original pulp, and the growth stage of the root formation. CASE suMMARY A 9-year-old girl complained of severe pain of the right maxillary incisor (tooth 12) when chewing for two weeks. Following clinical and radiographic examinations, Oehlers type III DI of tooth 12, with an immature open apical foramen and a symptomatic periapical pathosis, was diagnosed. Cone-beam computed tomography verified the specific spatial and stereoscopic data regarding the communication between the main root canal and pseudo root canal of the involved tooth. After removing the source of infection, a mineral trioxide aggregate was selected to fill and seal the pseudo root canal;additionally, pulp capping of the main canal was performed through the interconnections between the root canals in the middle segment to preserve pulp vitality and enable continual root formation and eventual root apex closure. CONCLUSION We propose to conduct main root canal pulp capping for DI with communication between the main and pseudo root canals.

关键词： Conservative treatment Dens invaginatus Open apex Cone-beam computed tomography Case report

Inhibition roles of molybdate and borate on Q235 steel corrosion in resistance reducing agent

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Journal of Iron and Steel Research International 2023年第8期30卷 1477-1489页

作者： Yang Yang hui su Lan-lan Liu Song Xu Zhen Zhong Xiao-bao Zhou Tang-qing Wu School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105HunanChina State Grid Hunan Electric Power Company Limited Transmission Maintenance Changsha 410100HunanChina State Grid Hunan Electric Power Company Limited Research Institute Changsha 410007HunanChina

The effects of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7) on corrosion behavior of Q235 steel in resistance reducing agent(RRA)containing sodium bentonite were studied by mass loss,scanning electron microscopy and electrochemical *** results showed that both the independent and mixed additions of Na_(2)MoO_(4) and/or Na_(2)B_(4)O_(7),can reduce the corrosion rate of Q235 steel in RRA containing sodium *** the inhibition effect of Na_(2)MoO_(4) and/or Na_(2)B_(4)O_(7)increased with their dosage *** the same dosage,the inhibition efficiency of the mixed addition of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7),was higher than that of their independent *** passivation effect of Q235 steel was easy to obtain in the RRA with the mixed addition of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7).The optimized inhibitor for the RRA containing sodium bentonite was the mixture of Na_(2)B_(4)O_(7) and Na_(2)MoO_(4) with a total concentration of 1.5 wt.%.Furthermore,the increase in corrosion potential E_(corr) and the decrease in corrosion current density i_(cor) in carbon steel were one of the important criteria for the formation of passivation film.

关键词： Q235 steel Resistance reducing agent Corrosion inhibitor Sodium bentonite Electrochemical impedance spectrum

Dynamically-evolved surface heterojunction in iridium nanocrystals boosting acidic oxygen evolution and overall water splitting

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Journal of Energy Chemistry 2023年第3期78卷 374-380,I0011页

作者： Chenyu Yang Xiuxiu Zhang Qizheng An Meihuan Liu Wanlin Zhou Yuanli Li Fengchun Hu Qinghua Liu hui su National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029AnhuiChina College of Chemistry and Chemical Engineering Hunan Normal UniversityChangsha 410081HunanChina Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory Southwest University of Science and TechnologyMianyang 621010SichuanChina

Simultaneously realizing improved activity and stability of acidic oxygen evolution reaction(OER) electrocatalysts is highly promising for developing cost-effective sustainable energy in the splitting of water ***,we report iridium nanocrystals embedded into 3D conductive clothes(Ir-NCT/CC) as a low iridium electrocatalyst realizing ultrahigh acidic OER activity and robust *** well-designed Ir-NCT/CC requires a low overpotential of 202 mV to reach the current density of 10 mA cm^(-2)with a high mass activity of 1754 A g^(-1).Importantly,in acidic overall water splitting,Ir-NCT/CC merely delivers a cell voltage of 1.469 V at a typical current density of 10 mA cm^(-2)and also maintains robust durability under continuous *** identify that a low working voltage drives the formation of a highly stable amorphous IrOxactive phase over the surface of Ir nanocrystals(surface heterojunction IrOx/Ir-NCT) during operating conditions,which contributes to an effective and durable OER process.

关键词： Electrocatalyst surface heterojunction In-situ synchrotron radiation techniques Reaction kinetics Acidic overall water splitting

Transient fuel performance analysis of UO_(2)–BeO fuel with composite SiC coated with Cr cladding based on multiphysics method

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Nuclear Science and Techniques 2023年第12期34卷 93-108页

作者： Chun‑Yu Yin Shi‑Xin Gao Sheng‑Yu Liu Rong Liu Guang‑hui su Li‑Bo Qian School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China School of Electric Power South China University of TechnologyGuangzhou 510640China

The transient multiphysics models were updated in CAMPUS to evaluate the accident-tolerant fuel performance under accident *** is a fuel performance code developed based on *** simulated results of the UO_(2)–Zircaloy fuel performance under accident conditions were compared with those of the FRAPTRAN code and the experimental data to verify the correctness of the updated ***,multiphysics models of the UO_(2)–BeO fuel and composite SiC coated with Cr(SiC_(f)/SiC-Cr)cladding were implemented in ***,the fuel performance of the three types of fuel cladding systems under Loss of Coolant Accident(LOCA)and Reactivity Insertion Accident(RIA)conditions was evaluated and compared,including the temperature distribution,stress distribution,pressure evolution,and cladding failure *** results showed that the fuel temperature of the UO_(2) fuel under accident conditions without pre-irradiation was lower after being combined with SiC_(f)/SiC-Cr ***,the centerline and outer surface temperatures of the UO_(2)–BeO fuel combined with SiC_(f)/SiC-Cr cladding reduced further under accident *** cladding temperature increased after the combination with the SiC_(f)/SiC-Cr cladding under accident conditions with *** addition,the use of SiC_(f)/SiC-Cr cladding significantly reduced the cladding hoop strain and plenum pressure.

关键词： Accident condition Fuel performance UO2–BeO fuel SiCf/SiC-Cr cladding

Melting Temperature of Individual Electrospun Poly(vinylidene fluoride) Fibers Studied by AFM-based Local Thermal Analysis

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Chinese Journal of Polymer Science 2021年第2期39卷 219-227,I0007页

作者： Ze-Qian Wang Zhen-Xing Zhong Yu-Ying Ma Xiao-Feng Lu Ce Wang Zhao-hui su State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China Alan G.MacDiarmid Institute Jilin UniversityChangchun 130012China

Thermal properties such as melting temperature can well reflect the microstructure of the polymer material, and have practical implications in the application of nanofibers. In this work, we investigated the melting temperature of individual electrospun poly(vinylidene fluoride)(PVDF) nanofibers with diameters ranging from smaller than 200 nm to greater than 2 μm by the local thermal analysis technique. The PVDF fibers obtained under four different conditions were found to crystallize into α and β phases, and the fiber mats showed typical values in the crystallinity and Tm with no significant difference among the four. However, analyses at single fiber level revealed broad distribution in diameter and Tm for the fibers produced under identical electrospinning condition. The Tm of individual nanofibers was found to remain constant at large diameters and increase quickly when reducing the fiber diameter toward the nanoscale, and Tm values of 220-230 ℃ were observed for the thinnest nanofibers, much higher than the typical values reported for bulk PVDF. The Tm and molecular orientation at different positions along a beaded fiber were analyzed, showing a similar distribution pattern with a minimum at the bead center and higher values when moving toward both directions. The results indicate that molecular orientation is the driving mechanism for the observed correlation between the Tm and the diameter of the nanofibers.

关键词： Electrospun fibers PVDF Local thermal analysis Melting temperature

Four new feather mite species of the genus Proctophyllodes Robin(Astigmata:Proctophyllodidae) from China

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动物分类学报 2014年第2期39卷 248-258页

作者： Zi-Ying Wang Jin-Jun Wang Xiao-hui su Institute of Entomology College of Plant ProtectionSouthwest University

Four new species of the feather mite genus Proctophyllodes are described from the birds of the order Passeriformes in China： P. flexuosa sp. nov. from Eophona migratoria Hartert （Chongqing）, P. brevis sp. nov. from Passer montanus （Linnaeus）（Anhui and Chongqing）, P. garrula sp. nov. from Garrulaxpoecilorhynchus Gould （Anhui）, P. canora sp. nov. from Garrulax canorus （Linnaeus）（Guizhou）.

关键词： Astigmata feather mites Proctophyllodes new species China.

Ir nanoclusters confined within hollow MIL-101(Fe)for selective hydrogenation ofα,β-unsaturated aldehyde

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Chinese Chemical Letters 2022年第1期33卷 374-377页

作者： Qinglin Liu Qian Liu Yurong Chen Yinle Li hui su Qinghua Liu Guangqin Li MOE Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China

Although the selective hydrogenation ofα,β-unsaturated aldehyde to unsaturated alcohol(UOL)is an extremely important transformation,it is still a great challenge to achieve high selectivity to UOL due to thermodynamic favoring of the C=C hydrogenation over the C=O ***,we report that iridium nanoclusters(Ir NCs)confined within hollow MIL-101(Fe)expresses satisfied reaction activity(93.9%)and high selectivity(96.2%)for the hydrogenation of cinnamaldehyde(CAL)to cinnamyl alcohol(COL)under 1 bar H;atmosphere and room *** unique hollow structure of MIL-101(Fe)benefits for the fast transport of reactant,ensuring the comparable reaction activity and better recyclability of Ir@MIL-101(Fe)than the counterparts which Ir NCs were on the surface of MIL-101(Fe).Furthermore,The X-ray photoelectron spectroscopy data indicates the electropositive Ir NCs,owing to the electron transfer from Ir to MIL-101(Fe),can interact with oxygen lone pairs,and Fourier transform infrared spectrum shows the Lewis acid sites in MIL-101(Fe)can strongly interact with C=O bond,which contributes to a high selectivity for *** work suggests the considerable potential of synergetic effect between hollow MOFs and metal nanoclusters for selective hydrogenation reactions.

关键词： Iridium Hollow metal-organic frameworks Selective hydrogenation α β-Unaturated aldehyde Heterogeneous catalysis

Platinum single-atom catalyst with self-adjustable valence state for large-current-density acidic water oxidation

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eScience 2022年第1期2卷 102-109页

作者： hui su Mikhail A.Soldatov Victor Roldugin Qinghua Liu National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei230029AnhuiPR China The Smart Materials Research Institute Southern Federal University344090Sladkova 178/24Rostov-on-DonRussia

The design of active acidic oxygen evolution reaction(OER)catalysts is of paramount importance to achieve efficient large-current-density industrial hydrogen fuel production via water ***,we develop a Pt-based catalyst with high electrochemical activity for the OER in acidic conditions under a large *** achieve this by modulating the electronic structure of Pt into a high-valence,electron-accessible Pt1^((2.4+δ)+)(δ=0-0.7)state during the *** electron-accessible Pt1^((2.4+δ)+)single-site catalyst can effectively maintain a large OER current density of 120 mA cm^(-2)for more than 12 h in 0.5 M H_(2)SO_(4) at a low overpotential of 405 mV,and it shows a high mass activity of~3350 A gmetal^(-1)at 10 mA cm^(-2) current density and 232 mV *** in situ synchrotron radiation infrared and X-ray absorption spectroscopies,we directly observe in an experiment that a key(*O)-Pt_(1)-C_(2)N_(2) intermediate is produced by the potential-driven structural optimization of square pyramidal Pt_(1)-C_(2)N_(2) moieties;this highly favors the dissociation of H_(2)O over Pt1^(2.4+δ)^(+)sites and prevents over-oxidation and dissolution of the active sites.

关键词： Oxygen evolution reaction Acidic electrolyte In situ characterization

Polarized few-layer g-C3N4 as metal-free electrocatalyst for highly efficient reduction of CO2

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Nano Research 2018年第5期11卷 2450-2459页

作者： Bing Zhang Tian-Jian Zhao Wei-Jie Feng Yong-Xing Liu Hong-hui Wang hui su Li-Bing Lv Xin-Hao Li Jie-Sheng Chen School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China

The greenhouse effect and global warming are serious problems because the increasing global demand for fossil fuels has led to a rapid rise in greenhouse gas exhaust emissions in the atmosphere and disruptive changes in climate. As a major contributor, CO2 has attracted much attention from scientists, who have attempted to convert it into useful products by electrochemical or photoelectrochemical reduction methods. Facile design of efficient but inexpensive and abundant catalysts to convert CO2 into fuels or valuable chemical products is essential for materials chemistry and catalysis in addressing global climate change as well as the energy crisis. Herein, we show that two-dimensional fewlayer graphitic carbon nitride （g-C3N4） can function as an efficient metal-free electrocatalyst for selective reduction of CO2 to CO at low overpotentials with a high Faradaic efficiency of - 80%. The polarized surface of ultrathin g-C3N4 layers （thickness： -1 nm）, with a more reductive conduction band, yields excellent electrochemical activity for CO2 reduction.

关键词： CO2 reduction two-dimensional (2D) materials metal-free electrocatalyst electrochemistry nanostructures