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Atomically Dispersed Zinc Active Sites Efficiently Promote the Electrochemical Conversion of N_(2) to NH_(3)
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作者 Yanjiao Wei Xinyu Wang +3 位作者 Mengjie Sun Min Ma jian tian Minhua Shao 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期175-181,共7页
At present,the research on highly active and stable nitrogen reduction reaction catalysts is still challenging work for the electrosynthesis of ammonia(NH_(3)).Herein,we synthesized atomically dispersed zinc active si... At present,the research on highly active and stable nitrogen reduction reaction catalysts is still challenging work for the electrosynthesis of ammonia(NH_(3)).Herein,we synthesized atomically dispersed zinc active sites supported on N-doped carbon nanosheets(Zn/NC NSs)as an efficient nitrogen reduction reaction catalyst,which achieves a high ammonia yield of 46.62μg h^(-1)mg^(-1)_(cat).at-0.85 V(vs RHE)and Faradaic efficiency of 95.8%at-0.70 V(vs RHE).In addition,Zn/NC NSs present great stability and selectivity,and there is no significant change in NH_(3)rate and Faradaic efficiencies after multiple cycles.The structural characterization shows that the active center in the nitrogen reduction reaction process is the Zn-N_(4)sites in the catalyst.DFT calculation confirms that Zn/NC with Zn-N_(4)configuration has a lower energy barrier for the formation of^(*)NNH intermediate compared with pure N-doped carbon nanosheets(N-C NSs),thus promoting the hydrogenation kinetics in the whole nitrogen reduction reaction process. 展开更多
关键词 ELECTROCATALYSIS nitrogen reduction single-atom catalyst Zn-N_(4)
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Multi-omics analysis of human tendon adhesion reveals that ACKR1-regulated macrophage migration is involved in regeneration
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作者 Xinshu Zhang Yao Xiao +9 位作者 Bo Hu Yanhao Li Shaoyang Zhang jian tian Shuo Wang Zaijin Tao Xinqi Zeng Ning-Ning Liu Baojie Li Shen Liu 《Bone Research》 SCIE CAS CSCD 2024年第2期390-406,共17页
Tendon adhesion is a common complication after tendon injury with the development of accumulated fibrotic tissues without effective anti-fibrotic therapies,resulting in severe disability.Macrophages are widely recogni... Tendon adhesion is a common complication after tendon injury with the development of accumulated fibrotic tissues without effective anti-fibrotic therapies,resulting in severe disability.Macrophages are widely recognized as a fibrotic trigger during peritendinous adhesion formation.However,different clusters of macrophages have various functions and receive multiple regulation,which are both still unknown.In our current study,multi-omics analysis including single-cell RNA sequencing and proteomics was performed on both human and mouse tendon adhesion tissue at different stages after tendon injury.The transcriptomes of over 74000 human single cells were profiled.As results,we found that SPP1^(+)macrophages,RGCC^(+)endothelial cells,ACKR1^(+)endothelial cells and ADAM12^(+)fibroblasts participated in tendon adhesion formation.Interestingly,despite specific fibrotic clusters in tendon adhesion,FOLR2^(+)macrophages were identified as an antifibrotic cluster by in vitro experiments using human cells.Furthermore,ACKR1 was verified to regulate FOLR2^(+)macrophages migration at the injured peritendinous site by transplantation of bone marrow from Lysm-Cre;R26R^(tdTomato) mice to lethally irradiated Ackr1^(-/-)mice(Ackr1^(-/-)chimeras;deficient in ACKR1)and control mice(WT chimeras).Compared with WT chimeras,the decline of FOLR2^(+)macrophages was also observed,indicating that ACKR1 was specifically involved in FOLR2^(+)macrophages migration.Taken together,our study not only characterized the fibrosis microenvironment landscape of tendon adhesion by multi-omics analysis,but also uncovered a novel antifibrotic cluster of macrophages and their origin.These results provide potential therapeutic targets against human tendon adhesion. 展开更多
关键词 TENDON ANALYSIS landscape
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Recent progress in research and design concepts for the characterization,testing,and photocatalysts for nitrogen reduction reaction 被引量:3
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作者 Benteng Sun Shucao Lu +2 位作者 Yeye Qian Xiaoli Zhang jian tian 《Carbon Energy》 SCIE CSCD 2023年第3期19-74,共56页
The reduction of molecular nitrogen(N_(2))to ammonia(NH_(3))under mild conditions is one of the most promising studies in the energy field due to the important role of NH_(3)in modern industry,production,and life.The ... The reduction of molecular nitrogen(N_(2))to ammonia(NH_(3))under mild conditions is one of the most promising studies in the energy field due to the important role of NH_(3)in modern industry,production,and life.The photocatalytic reduction of N_(2)is expected to achieve clean and sustainable NH_(3)production by using clean solar energy.To date,the new photocatalysts for photocatalytic reduction of N_(2)to NH_(3)at room temperature and atmospheric pressure have not been fully developed.The major challenge is to achieve high light-absorption efficiency,conversion efficiency,and stability of photocatalysts.Herein,the methods for measuring produced NH_(3)are compared,and the problems related to possible NH_(3)pollution in photocatalytic systems are mentioned to provide accurate ideas for measuring photocatalytic efficiency.The recent progress of nitrogen reduction reaction(NRR)photocatalysts at ambient temperature and pressure is summarized by introducing charge transfer,migration,and separation in photocatalytic NRR,which provides a guidance for the selection of future photocatalyst.More importantly,we introduce the latest research strategies of photocatalysts in detail,which can guide the preparation and design of photocatalysts with high NRR activity. 展开更多
关键词 nitrogen reduction reaction PHOTOCATALYSTS produced NH 3 measuring methods reaction mechanism research strategy
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Heterostructuring noble-metal-free 1T'phase MoS_(2) with g-C_(3)N_(4) hollow nanocages to improve the photocatalytic H2 evolution activity 被引量:2
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作者 Yanjun Xue Yinghong Ji +4 位作者 Xinyu Wang Huanli Wang Xiaobo Chen Xiaoli Zhang jian tian 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期864-873,共10页
In this work,we report the preparation of 1T'-MoS_(2)/g-C_(3)N_(4) nanocage(NC)heterostructure by loading 2D semi-metal noble-metal-free 1T'-MoS_(2) on the g-C_(3)N_(4) nanocages(NCs).DFT calculation and exper... In this work,we report the preparation of 1T'-MoS_(2)/g-C_(3)N_(4) nanocage(NC)heterostructure by loading 2D semi-metal noble-metal-free 1T'-MoS_(2) on the g-C_(3)N_(4) nanocages(NCs).DFT calculation and experimental data have shown that the 1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure has a stronger light absorption capacity and larger specific surface area than pure g-C_(3)N_(4) NCs and g-C_(3)N_(4) nanosheets(NSs),and the presence of the co-catalysts 1T'-MoS_(2) can effectively inhibit the photoinduced carrier recombination.As a result,the 1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure with an optimum 1T'-MoS_(2) loading of 9 wt%displays a hydrogen evolution rate of 1949 mmol h^(-1) g^(-1),162.4,1.2,1.5,1.6 and 1.2 times than pure g-C_(3)N_(4) NCs(12 mmol h^(-1) g^(-1)),Pt/g-C_(3)N_(4) NCs(1615 mmol h^(-1) g^(-1))and Pt/g-C_(3)N_(4) nanosheets(NSs,1297 mmol h^(-1) g^(-1)),1T'-MoS_(2)/g-C_(3)N_(4) nanosheets(1216 mmol h^(-1) g^(-1))and 2H-MoS_(2)/g-C_(3)N_(4) nanocages(1573 mmol h^(-1) g^(-1)),respectively,and exhibits excellent cycle stability.Therefore,1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure is a suitable photocatalyst for green H_(2) production. 展开更多
关键词 g-C_(3)N_(4) 1T'phase MoS_(2) Nanocage structure Photocatalytic hydrogen production Co-catalysts
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Surface hydrophobic modification of MXene to promote the electrochemical conversion of N_(2) to NH_(3) 被引量:1
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作者 Xu Wang Rui Zhang +6 位作者 Chaoqun Ma Wei Yan Yanjiao Wei jian tian Min Ma Qing Li Minhua Shao 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期439-449,I0011,共12页
Hydrophobic treatment of the catalyst surfaces can suppress the competitive hydrogen evolution reaction(HER) during the nitrogen reduction reaction(NRR).In this work,the surface of Ti_(3)C_(2)Ti_(x) MXene is modified ... Hydrophobic treatment of the catalyst surfaces can suppress the competitive hydrogen evolution reaction(HER) during the nitrogen reduction reaction(NRR).In this work,the surface of Ti_(3)C_(2)Ti_(x) MXene is modified by cetyltrimethylammonium bromide(CTAB) and trimethoxy(3,3,4,4,5,5,6,6,7,7,8,8,8-trideca fluorooctyl) silane(FOTS) to increase the hydrophobicity of MXenes.The ammonia(NH_(3)) production rate and faradaic efficiency(FE) are improved from 37.62 to 54.01 μg h^(-1)mg_(cat)^(-1).and 5.5% to 18.1% at-0.7 V vs.RHE,respectively after surface modification.^(15)N isotopic labeling experiment confirms that nitrogen in produced ammonia originates from N_(2) in the electrolyte.The excellent NRR activity of surface hydrophobic MXenes is mainly due to surfactant molecules,which inhibit the entry of water molecules and the competitive HER,which have been verified by in situ FT-IR,DFT and molecular dynamics calculations.This strategy provides an ingenious method to design more active NRR electrocatalysts. 展开更多
关键词 ELECTROCATALYSIS Nitrogen reduction reaction Surface hydrophobic modification MXene Ti_(3)C_(2)Ti_(x)
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Insight into the dynamic adsorption behavior of graphene oxide multichannel architecture toward contaminants
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作者 jian tian Gen Li +4 位作者 Wang He Kok Bing Tan Daohua Sun Junfu Wei Qingbiao Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期124-132,共9页
Graphene oxide(GO) channels exhibit unique mass transport behaviors due to their flexibility, controllable thinness and extraordinary physicochemical properties, enabling them to be widely used for adsorption and memb... Graphene oxide(GO) channels exhibit unique mass transport behaviors due to their flexibility, controllable thinness and extraordinary physicochemical properties, enabling them to be widely used for adsorption and membrane separation. Nevertheless, the adsorption behavior of nanosized contaminants within the channels of GO membrane has not been fully discussed. In this study, we fabricated a GO membrane(PGn, where n represents the deposition cycles of GO) with multi channels via the crosslinking of GO and multibranched poly(ethyleneimine)(PEI). Phenol was used as molecular probe to determine the correlations between dynamic adsorption behavior and structural parameters of the multilevel GO/PEI membrane. PG8 shows higher adsorption capacities and affinity, which is predominantly attributed to the multichannel structure providing a large specific surface for phenol adsorption, enhancing the accessibility of active sites for phenol molecules and the transport of phenol. Density functional theory calculations demonstrate that the adsorption mechanism of phenol within GO channel is energetically oriented by hydrogen bonds, which is dominated by oxygen-containing groups compared to amino groups. Particularly, the interfaces which facilitate strong π-π interaction and hydrogen bonds maybe the most active regions. Moreover, the as-prepared PG8 membrane showed outstanding performance for other contaminants such as methyl orange and Cr(VI). It is anticipated that this study will have implications for design of GO-related environmental materials with enhanced efficiency. 展开更多
关键词 Graphene oxide MULTICHANNEL Adsorptive behavior PHENOL DFT calculations
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The incorporation of cocatalyst cobalt sulfide into graphitic carbon nitride:Boosted photocatalytic hydrogen evolution performance and mechanism exploration
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作者 Zhangqian Liang Yanjun Xue +3 位作者 Xinyu Wang Xiaoli Zhang jian tian Hongzhi Cui 《Nano Materials Science》 EI CAS CSCD 2023年第2期202-209,共8页
2D-layered graphitic carbon nitride(g-C_(3)N_(4))is regarded as a great prospect as a photocatalyst for H_(2)generation.However,g-C_(3)N_(4)’s photocatalytic hydrogen evolution(HER)activity is significantly restricte... 2D-layered graphitic carbon nitride(g-C_(3)N_(4))is regarded as a great prospect as a photocatalyst for H_(2)generation.However,g-C_(3)N_(4)’s photocatalytic hydrogen evolution(HER)activity is significantly restricted by the recombination of photocarriers.We find that cobalt sulfide(CoS_(2))as a cocatalyst can promote g-C_(3)N_(4)nanosheets(NSs)to realize very efficient photocatalytic H_(2)generation.The prepared CoS_(2)/g-C_(3)N_(4)hybrids display highly boosted photocatalytic H_(2)generation performance and outstanding cycle stability.The optimized 7%-CoS_(2)/g-C_(3)N_(4)hybrids show a much improved photocatalytic H_(2)generation rate of 36.2μmol-1h-1,which is about 180 times as much as bare g-C_(3)N_(4)(0.2μmol-1h-1).In addition,the apparent quantum efficiency(AQE)of all the samples was computed under light atλ=370 nm,in which the AQE of 7%-CoS_(2)/g-C_(3)N_(4)hybrids is up to 5.72%.The experimental data and the DFT calculation suggest that the CoS_(2)/g-C_(3)N_(4)hybrid’s excellent HER activity is attributable to the lower overpotential and the smaller Co-H bond activation energy for HER.Accordingly,the CoS_(2)cocatalyst loading effectively boosts the photocatalytic performance of g-C_(3)N_(4)for H_(2)evolution.The project promotes fast development of high-efficiency photocatalysts and low-cost for photocatalytic H_(2)generation. 展开更多
关键词 Non-precious-metal cocatalysts Photocatalytic hydrogen evolution reaction CoS_(2)cocatalysts 2D-layered g-C_(3)N_(4)
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Experimental Study on the Treatment of Tertiary Oil Recovery Wastewater via a Novel Electro-Coagulation Method
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作者 Wei Cui Zhilun Yan +3 位作者 Zhi Tang Mengyao Xu jian tian Chengyi Shen 《Fluid Dynamics & Materials Processing》 EI 2023年第1期51-60,共10页
At present,methods for treating tertiary oil recovery wastewater via electro-coagulation are still in their early stage of development.In this study,a device for electro-coagulation wastewater treatment was built and ... At present,methods for treating tertiary oil recovery wastewater via electro-coagulation are still in their early stage of development.In this study,a device for electro-coagulation wastewater treatment was built and tested in an oil field.The effects that the initial pH value,electrode type,and connection mode have on the coagulation and separation effect were assessed by measuring the mass fraction and turbidity of oil.The results have shown that when the electro-coagulation method is used,the effectiveness of the treatment can be significantly increased in neutral pH conditions(pH=7),in acidic conditions,and in alkaline conditions.Compared to an Al electrode,the floc that is produced by an Fe electrode is smaller;thus,it does not easily coagulate and settle in a short time.Using the oil removal rate,turbidity removal rate and energy consumption as a basis to assess the performances,the results have demonstrated that the combined aluminum alloy iron composite electrode should be used as electrolytic electrode. 展开更多
关键词 ELECTROCOAGULATION oily sewage POLYMER experiment study
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Maintenance Strategy of Multi-Component System Due to Degradation and Shock
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作者 Yijie Chen jian tian 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第2期73-83,共11页
The proposed maintenance strategy uses component grades and survival signature to describe and update system structure. A system dynamic stress-strength reliability(SSR) model was established to describe component fai... The proposed maintenance strategy uses component grades and survival signature to describe and update system structure. A system dynamic stress-strength reliability(SSR) model was established to describe component failure processes because of internal degradation and external shock. Besides, a corrective maintenance rule and two-level preventive maintenance rule made up the proposed maintenance strategy. The former combined sequentially minimal repair and corrective replacement(SMRCR) based on system structure updating. The latter considered group importance measure based on the system dynamic SSR and preventive maintenance cost. Further, a cost model was developed by the proposed strategy, and the optimal decision variables were found by genetic algorithm. Finally, using a case system to illustrate the above strategy improved system and reduced maintenance costs. 展开更多
关键词 survival signature system structure updating system dynamic stress-strength reliability group importance measure
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Application of Monte Carlo method to calculate the effective delayed neutron fraction in molten salt reactor 被引量:6
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作者 Gui-Feng Zhu Rui Yan +5 位作者 Hong-Hua Peng Rui-Min Ji Shi-He Yu Ya-Fen Liu jian tian Bo Xu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第2期143-152,共10页
Delayed neutron loss is an important parameter in the safety analysis of molten salt reactors. In this study,to obtain the effective delayed neutron fraction under flow condition, a delayed neutron precursor transport... Delayed neutron loss is an important parameter in the safety analysis of molten salt reactors. In this study,to obtain the effective delayed neutron fraction under flow condition, a delayed neutron precursor transport was implemented in the Monte Carlo code MCNP. The moltensalt reactor experiment(MSRE) model was used to analyze the reliability of this method. The obtained flow losses of reactivity for 235 U and 233 U fuels in the MSRE are223 pcm and 100.8 pcm, respectively, which are in good agreement with the experimental values(212 pcm and100.5 pcm, respectively). Then, six groups of effective delayed neutron fractions in a small molten salt reactor were calculated under different mass flow rates. The flow loss of reactivity at full power operation is approximately105.6 pcm, which is significantly lower than that of the MSRE due to the longer residence time inside the active core. The sensitivity of the reactivity loss to other factors,such as the residence time inside or outside the core and flow distribution, was evaluated as well. As a conclusion,the sensitivity of the reactivity loss to the residence time inside the core is greater than to other parameters. 展开更多
关键词 MONTE Carlo EFFECTIVE DELAYED neutron FRACTION MOLTEN SALT reactor
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Photocatalytic H2 Evolution on TiO2 Assembled with Ti3C2 MXene and Metallic 1T-WS2 as Co-catalysts 被引量:6
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作者 Yujie Li Lei Ding +5 位作者 Shujun Yin Zhangqian Liang Yanjun Xue Xinzhen Wang Hongzhi Cui jian tian 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第1期63-74,共12页
The biggest challenging issue in photocatalysis is efficient separation of the photoinduced carriers and the aggregation of photoexcited electrons on photocatalyst’s surface.In this paper,we report that double metall... The biggest challenging issue in photocatalysis is efficient separation of the photoinduced carriers and the aggregation of photoexcited electrons on photocatalyst’s surface.In this paper,we report that double metallic co-catalysts Ti3C2 MXene and metallic octahedral(1T)phase tungsten disulfide(WS2)act pathways transferring photoexcited electrons in assisting the photocatalytic H2 evolution.TiO2 nanosheets were in situ grown on highly conductive Ti3C2 MXenes and 1T-WS2 nanoparticles were then uniformly distributed on TiO2@Ti3C2 composite.Thus,a distinctive 1T-WS2@TiO2@Ti3C2 composite with double metallic co-catalysts was achieved,and the content of 1T phase reaches 73%.The photocatalytic H2 evolution performance of 1T-WS2@TiO2@Ti3C2 composite with an optimized 15 wt%WS2 ratio is nearly 50 times higher than that of TiO2 nanosheets because of conductive Ti3C2 MXene and 1T-WS2 resulting in the increase of electron transfer efficiency.Besides,the 1T-WS2 on the surface of TiO2@Ti3C2 composite enhances the Brunauer–Emmett–Teller surface area and boosts the density of active site. 展开更多
关键词 Photocatalytic H2 production Ti3C2 MXene Octahedral phase WS2 TiO2 nanosheets Co-catalysts
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Boosting the photocatalytic performance of Ag_2CO_3 crystals in phenol degradation via coupling with trace N-CQDs 被引量:7
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作者 jian tian Renyue Liu +2 位作者 Zhen Liu Changlin Yu Minchao Liu 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第12期1999-2008,共10页
A series of N‐CQDs/Ag2CO3composite crystals(where N‐CQDs=Nitrogen doped carbon quantumdots)were prepared by adding different volumes of a solution of N‐CQDs during Ag2CO3crystalgrowth.Under irradiation from a350‐W... A series of N‐CQDs/Ag2CO3composite crystals(where N‐CQDs=Nitrogen doped carbon quantumdots)were prepared by adding different volumes of a solution of N‐CQDs during Ag2CO3crystalgrowth.Under irradiation from a350‐W Xe lamp light(with optical filter,λ≥420nm),the performanceof N‐CQDs/Ag2CO3in photocatalytic degradation of phenol was evaluated.The as‐preparedsamples were analyzed by XRD,SEM,TEM,BET,element mapping,UV‐vis DRS,FT‐IR,XPS,transientphotocurrent response and EIS testing.The results showed that after coupling with trace amountsof N‐CQDs,both the photocatalytic activity and stability of Ag2CO3were greatly boosted.The additionof N‐CQDs solution influenced the crystallization of Ag2CO3,resulting in a distinct decrease inAg2CO3crystal size and an obvious increase in surface area.Moreover,the charge transfer resistancewas greatly reduced,and the separation efficiency of photogenerated electrons and holes wasstrongly promoted.The presence of NCQDs on the surface of the catalysts facilitates the transfer ofphotogenerated electrons,slowing the photocorrosion rate of Ag2CO3,and then resulting in higherstability than bare Ag2CO3in degradation.The synergistic effect of the improvement of morphologyand charge transfer rate thus accounted for the superior photocatalytic performance ofN‐CQDs/Ag2CO3. 展开更多
关键词 Ag2CO3 Nitrogen doped carbon quantum dots PHOTOCATALYSIS Stability and activity PHENOL
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The effectiveness and safety of the RESTORE R drug-eluting balloon versus a drug-eluting stent for small coronary vessel disease: study protocol for a multi-center, randomized, controlled trial 被引量:5
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作者 Yi-Da TANG Shu-Bin QIAO +16 位作者 Xi SU Yun-Dai CHEN Ze-Ning JIN Hui CHEN Biao XU Xiang-Qing KONG Wen-Yue PANG Yong LIU Zai-Xin YU Xue LI Hui LI Yan-Yan ZHAO Wei LI jian tian Chang-Dong GUAN Bo XU Run-Lin GAO 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第7期469-475,共7页
bjective Small coronary vessel disease (disease affecting coronary vessels with main branch diameters of 〈 2.75 mm) is a common and intractable problem in percutaneous coronary intervention (PCI). This study was ... bjective Small coronary vessel disease (disease affecting coronary vessels with main branch diameters of 〈 2.75 mm) is a common and intractable problem in percutaneous coronary intervention (PCI). This study was designed to test the theory that the effectiveness and safety of drug-eluting balloons for the treatment of de novo lesions in small coronary vessels are non-inferior to those of drug-eluting stents. Methods We designed a prospective, multicenter, randomized, controlled clinical trial aiming to assess the effectiveness and safety of the RESTORE R (Cardionovum, Bonn, Germany) drug-eluting balloon (DEB) versus the RESOLUTE R (Medtronic, USA) drug-eluting stent (DES) in the treatment of small coronary vessel disease. This trial started in August 2016. A total of 230 patients with a reference vessel diameter (RVD) 〉 2.25 mm and 〈 2.75 mm were randomly assigned to treatment with a DEB or a DES at a 1:1 ratio. The study was also designed to enroll 30 patients with an RVD 〉 2.00 mm and 〈 2.25 mm in the tiny vessel cohort. Results The key baseline data include demographic characteristics, relative medical history, baseline angiographic values and baseline procedural characteristics. The primary endpoint is in-segment diameter stenosis at nine months after the index procedure. Secondary endpoints include acute success, all-cause death, myocardial infarction, target vessel revascularization, target lesion revascularization and stent thrombosis. Conclusions The study will evaluate the clinical efficacy, angiographic outcomes, and safety of DEBs compared to DESs in the treatment of de novo coronary artery lesions in small vessels. 展开更多
关键词 Drag eluting balloon Percutaneous coronary intervention Small vessel disease
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Solvothermal fabrication of Bi_(2)MoO_(6) nanocrystals with tunable oxygen vacancies and excellent photocatalytic oxidation performance in quinoline production and antibiotics degradation 被引量:3
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作者 Zhen Liu jian tian +2 位作者 Changlin Yu Qizhe Fan Xingqiang Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第2期472-484,共13页
Novel Bi_(2)MoO_(6) nanocrystals with tunable oxygen vacancies have been developed via a facile low-cost approach with the assistance of a glyoxal reductant under solvothermal conditions.With the introduction of oxyge... Novel Bi_(2)MoO_(6) nanocrystals with tunable oxygen vacancies have been developed via a facile low-cost approach with the assistance of a glyoxal reductant under solvothermal conditions.With the introduction of oxygen vacancies,the optical absorption of Bi_(2)MoO_(6) is extended and its bandgap narrowed.Oxygen vacancies not only lead to the appearance of a defect band level in the forbidden band but can also result in a minor up-shift of the valence band maximum,promoting the mobility of photogenerated holes.Moreover,oxygen vacancies can act as electron acceptors,temporarily capturing electrons excited by light and reducing the recombination of electrons and holes.At the same time,oxygen vacancies help to capture oxygen,which reacts with the captured photogenerated electrons to generate more superoxide radicals(·O_(2)-)to participate in the reaction,thereby significantly promoting the redox performance of the photocatalyst.From Bi_(2)MoO_(6) containing these oxygen vacancies(OVBMO),excellent photocatalytic performance has been obtained for the oxidation of 1,2,3,4-tetrahydroquinoline to produce quinoline and cause antibiotic degradation.The reaction mechanism of the oxidation of 1,2,3,4-tetrahydroquinoline to quinoline over the OVBMO materials is elucidated in terms of heterogeneous Catal.via a radical pathway. 展开更多
关键词 Bi_(2)MoO_(6)nanocrystals Oxygen vacancies Photocatalytic oxidation performance Quinoline production Antibiotics degradation
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Avoiding sealing failure of flanged connection for tubes made of dissimilar materials subjected to elevated temperature 被引量:2
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作者 Qi-Ming Li Chong Zhou +3 位作者 jian tian Yao Fu Yang Zou Na-Xiu Wang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第1期107-112,共6页
Carbonic composite materials and ceramics appear to be excellent structural materials for parts subjected to very high temperatures in molten salt reactors(MSRs), in which the reactor core outlet temperature is normal... Carbonic composite materials and ceramics appear to be excellent structural materials for parts subjected to very high temperatures in molten salt reactors(MSRs), in which the reactor core outlet temperature is normally above 700℃. Because of the high temperature,there are major challenges in the sealing of flanged connections for tubes made of alloys and nonmetallic materials. In this study, an improved method for sealing bolted flange connections for tubes made of dissimilar materials at high temperature is analyzed. The study focuses on the compensation mechanism for the difference in thermal expansion between the bolts and the flanges. An angle is introduced for the sealing surface in the flanged connection to provide effective sealing. The arctangent of the angle is the ratio of the thickness between the theoretical core of the sealing surface and the outside end face of the flange to the distances between the axis of the flanged joint and the theoretical core of the sealing surface of the flange; the sealing surface of the flange, which is made of the same material as the fastening assemblies, faces the fastening assemblies. To ensure effective sealing, the frictional coefficient between the two sealing surfaces should not exceed the tangent of the angle. This result does not agree well with the solution given by previous researchers. Further, in the modified flanged connection, the compression of each bolt in the clamped condition is increased to maintain the compaction force unchanged without increasing the number of bolts on the flanged joint. 展开更多
关键词 SEALING Composite flanged CONNECTIONS Thermal expansion Mechanical analysis MOLTEN SALT reactors
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浅谈异分化在放射诱导肺纤维化中的作用
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作者 肖子婷 田健 +3 位作者 化改改 朱琰琰 张星南 周建炜 《中国现代医学杂志》 CAS 2019年第20期39-42,共4页
肺纤维化即损伤后的肺上皮细胞为胶原和细胞外基质所取代,其过程不可逆,5年生存率仅为20%~30%,患者最终死于肺衰竭。在不同治疗阶段,60%肺癌患者需接受放射治疗;30%患者发生肺损伤,最终可能会诱导纤维化发生。目前对放疗导致的纤维化确... 肺纤维化即损伤后的肺上皮细胞为胶原和细胞外基质所取代,其过程不可逆,5年生存率仅为20%~30%,患者最终死于肺衰竭。在不同治疗阶段,60%肺癌患者需接受放射治疗;30%患者发生肺损伤,最终可能会诱导纤维化发生。目前对放疗导致的纤维化确切机制缺乏了解,该文主要对放射性肺纤维化的研究进展,以及笔者正在从事的相关研究进行综述,以期了解发生肺纤维化的可能机制。 展开更多
关键词 肺肿瘤 成体干细胞 转化生长因子Β 肺纤维化 综述
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Assessment of causal direction between thyroid function and cardiometabolic health:a Mendelian randomization study 被引量:3
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作者 Jing-Jia WANG Zhen-Huang ZHUANG +11 位作者 Can-Qing YU Wen-Yao WANG Wen-Xiu WANG Kuo ZHANG Xiang-Bin MENG Jun GAO jian tian Ji-Lin ZHENG Jie YANG Tao HUANG Chun-Li SHAO Yi-Da TANG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2022年第1期61-70,共10页
BACKGROUND Growing evidence have demonstrated that thyroid hormones have been involved in the processes of cardiovascular metabolism.However,the causal relationship of thyroid function and cardiometabolic health remai... BACKGROUND Growing evidence have demonstrated that thyroid hormones have been involved in the processes of cardiovascular metabolism.However,the causal relationship of thyroid function and cardiometabolic health remains partly unknown.METHODS The Mendelian randomization(MR)was used to test genetic,potentially causal relationships between instrumental variables and cardiometabolic traits.Genetic variants of free thyroxine(FT4)and thyrotropin(TSH)levels within the reference range were used as instrumental variables.Data for genetic associations with cardiometabolic diseases were acquired from the genome-wide association studies of the FinnGen,CARDIoGRAM and CARDIoGRAMplusC4D,CHARGE,and MEGASTROKE.This study was conducted using summary statistic data from large,previously described cohorts.Association between thyroid function and essential hypertension(EHTN),secondary hypertension(SHTN),hyperlipidemia(HPL),type 2 diabetes mellitus(T2DM),ischemic heart disease(IHD),myocardial infarction(MI),heart failure(HF),pulmonary heart disease(PHD),stroke,and non-rheumatic valve disease(NRVD)were examined.RESULTS Genetically predicted FT4 levels were associated with SHTN(odds ratio=0.48;95%CI=0.04−0.82,P=0.027),HPL(odds ratio=0.67;95%CI=0.18−0.88,P=0.023),T2DM(odds ratio=0.80;95%CI=0.42−0.86,P=0.005),IHD(odds ratio=0.85;95%CI=0.49−0.98,P=0.039),NRVD(odds ratio=0.75;95%CI=0.27−0.97,P=0.039).Additionally,genetically predicted TSH levels were associated with HF(odds ratio=0.82;95%CI=0.68−0.99,P=0.042),PHD(odds ratio=0.75;95%CI=0.32−0.82,P=0.006),stroke(odds ratio=0.95;95%CI=0.81−0.97,P=0.007).However,genetically predicted thyroid function traits were not associated with EHTN and MI.CONCLUSIONS Our study suggests FT4 and TSH are associated with cardiometabolic diseases,underscoring the importance of the pituitary-thyroid-cardiac axis in cardiometabolic health susceptibility. 展开更多
关键词 cardio FUNCTION RANDOM
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Low-cost and efficient visible-light-driven CaMg(CO_3)_2@Ag_2CO_3 microspheres fabricated via an ion exchange route 被引量:4
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作者 jian tian Zhen Wu +5 位作者 Zhen Liu Changlin Yu Kai Yang Lihua Zhu Weiya Huang Yang Zhou 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第11期1899-1908,共10页
CaMg(CO3)2microspheres were prepared and used as hard templates to fabricate a series of CaMg(CO3)2@Ag2CO3composite microspheres via a fast and low‐cost ion exchange process.The effects of ion exchange time and tempe... CaMg(CO3)2microspheres were prepared and used as hard templates to fabricate a series of CaMg(CO3)2@Ag2CO3composite microspheres via a fast and low‐cost ion exchange process.The effects of ion exchange time and temperature on the physicochemical properties and photocatalytic activities of the composite microspheres were studied through photocatalytic degradation of Acid Orange II under xenon lamp irradiation.The obtained samples were analyzed by X‐ray diffraction,scanning electron microscopy,Fourier transform infrared spectroscopy,UV‐vis diffuse reflectance spectroscopy,N2physical adsorption,and photocurrent tests.The CaMg(CO3)2@Ag2CO3sample with the highest activity was obtained with an ion exchange time of4h and temperature of40°C.The degradation rate of Acid Orange II by this sample reached83.3%after15min of light irradiation,and the sample also performed well in phenol degradation.The CaMg(CO3)2@Ag2CO3produced under these ion exchange conditions showed a well‐ordered hierarchical morphology with small particle sizes,which was beneficial to light absorption and the transfer of photoelectrons(e-)and holes(h+)to the catalyst surface.Moreover,the separation of photogenerated carriers over the composites was greatly improved relative to bare CaMg(CO3)2.Despite the very low content of Ag2CO3(2.56%),excellent photocatalytic performance was obtained over the CaMg(CO3)2@Ag2CO3microspheres. 展开更多
关键词 Hard template Ion exchange CaMg(CO3)2@Ag2CO3 microspheres Photocatalytic performance
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Experimental study on the penetration characteristics of leaking molten salt in the thermal insulation layer of aluminum silicate fiber 被引量:2
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作者 Yun Wang jian tian +2 位作者 Shan-Wu Wang Chong Zhou Na-Xiu Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第9期27-39,共13页
The molten salt leakage accident is an important issue in the nuclear safety analysis of molten salt reactors.While the molten salt leaks from the pipeline or storage tank,it will contact the insulation layer outside;... The molten salt leakage accident is an important issue in the nuclear safety analysis of molten salt reactors.While the molten salt leaks from the pipeline or storage tank,it will contact the insulation layer outside;hence,the processes of penetration and spreading play an important role in the development of leakage accidents.In this study,the penetration and diffusion of leaking molten salt(LMS)in an aluminum silicate fiber(ASF)thermal insulation layer were studied experimentally.A molten salt tank with an adjustable outlet was designed to simulate the leakage of molten salt,and the subsequent behavior in the thermal insulation layer was evaluated by measuring the penetra-tion time and penetration mass of the LMS.The results show that when the molten salt discharges from the outlet and reaches the thermal insulation layer,the LMS will penetrate and seep out from the ASF,and a higher flow rate of LMS requires less penetration time and leaked mass of LMS.As the temperature of the LMS and thickness of the ASF increased,the penetration time became longer and the leaked mass became greater at a lower LMS flow rate;when the LMS flow rate increased,the penetration time and leaked mass decreased rapidly and tended to flatten. 展开更多
关键词 Molten salt reactor Molten salt leakage PENETRATION Insulation layer
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Investigating nuclear dissipation properties at large deformations via excitation energy at scission 被引量:1
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作者 jian tian Wei Ye 《Nuclear Science and Techniques》 SCIE CAS CSCD 2016年第6期33-37,共5页
Using the stochastic Langevin model coupled with a statistical decay model,we study nuclear dissipation properties at large deformations with excitation energy at scission(E*_(sc)) measured in experiments.It is found ... Using the stochastic Langevin model coupled with a statistical decay model,we study nuclear dissipation properties at large deformations with excitation energy at scission(E*_(sc)) measured in experiments.It is found that the postsaddle dissipation strength required to fit E*_(sc) data is 12*10^(21) s^(-1)for^(254;256)Fm and 6*10^(21) s^(-1)for^(189)Au,which has a smaller postsaddle deformation than the former heavy nucleus,showing a rise of nuclear dissipation strength with increasing deformation. 展开更多
关键词 断裂能量 核耗散 大变形 激发能 特性 测量实验 模型 SC
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