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1Synergistic effect between Sn and K promoters on supported platinum catalyst for isobutane dehydrogenation显示文摘Catalytic dehydrogenation of isobutane has recently received considerable attention because of the increasing demand for isobutene.In this study,the synergistic effect between Sn and K on PtSnK/γ-Al2O3 catalysts has been investigated by changing the content of Sn.It was found that with the presence of potassium,suitable addition of Sn could not only increase the metal dispersion,but also reduce the catalyst acidity.In these cases,the synergistic effect could also strengthen the interactions between the metal and support,which resulted in an increase in both catalytic activity and stability.In our experiments,Pt-0.6SnK/Al catalyst exhibited the lowest deactivation rate (12.4%) and showed a selectivity to isobutene higher than 94% at the isobutane conversion of about 45.3% after running the reaction for 6 h.However,with the excessive loading of Sn,surface property of active sites and the interactions between metal and support were changed.As a result,the initial optimal ratio between the metallic function and acid function would be destroyed,which was disadvantageous to the reaction.Yiwei Zhang Yuming Zhou Lihui Wan Mengwei Xue Yongzheng Duan Xuan Liu 2011Journal of Natural Gas Chemistry2011,20,6:12
2Humoral immune response to circulating SARS-CoV-2 variants elicited by inactivated and RBD-subunit vaccines显示文摘SARS-CoV-2 variants could induce immune escape by mutations on the receptor-binding domain(RBD)and N-terminal domain(NTD).Here we report the humoral immune response to circulating SARS-CoV-2 variants,such as 501Y.V2(B.1.351),of the plasma and neutralizing antibodies(NAbs)elicited by CoronaVac(inactivated vaccine),ZF2001(RBD-subunit vaccine)and natural infection.Among 86 potent NAbs identified by high-throughput single-cell VDJ sequencing of peripheral blood mononuclear cells from vaccinees and convalescents,near half anti-RBD NAbs showed major neutralization reductions against the K417N/E484K/N501Y mutation combination,with E484K being the dominant cause.VH3-53/VH3-66 recurrent antibodies respond differently to RBD variants,and K417N compromises the majority of neutralizing activity through reduced polar contacts with complementarity determining regions.In contrast,the 242–244 deletion(242–244Δ)would abolish most neutralization activity of anti-NTD NAbs by interrupting the conformation of NTD antigenic supersite,indicating a much less diversity of anti-NTD NAbs than anti-RBD NAbs.Plasma of convalescents and CoronaVac vaccinees displayed comparable neutralization reductions against pseudo-and authentic 501Y.V2 variants,mainly caused by E484K/N501Y and 242–244Δ,with the effects being additive.Importantly,RBD-subunit vaccinees exhibit markedly higher tolerance to 501Y.V2 than convalescents,since the elicited anti-RBD NAbs display a high diversity and are unaffected by NTD mutations.Moreover,an extended gap between the third and second doses of ZF2001 leads to better neutralizing activity and tolerance to 501Y.V2 than the standard three-dose administration.Together,these results suggest that the deployment of RBD-vaccines,through a third-dose boost,may be ideal for combating SARS-CoV-2 variants when necessary,especially for those carrying mutations that disrupt the NTD supersite.Yunlong Cao Ayijiang Yisimayi Yali Bai Weijin Huang Xiaofeng Li Zhiying Zhang Tianjiao Yuan Ran An Jing Wang Tianhe Xiao Shuo Du Wenping Ma Liyang Song Yongzheng Li Xiang Li Weiliang Song Jiajing Wu Shuo Liu Xuemei Li Yonghong Zhang Bin Su Xianghua Guo Yangyang Wei Chuanping Gao Nana Zhang Yifei Zhang Yang Dou Xiaoyu Xu Rui Shi Bai Lu Ronghua Jin Yingmin Ma Chengfeng Qin Youchun Wang Yingmei Feng Junyu Xiao Xiaoliang Sunney Xie 2021Cell Research2021,31,7:12
3Deformation characteristics and reinforcement technology for entry subjected to mining-induced stresses显示文摘The entry at Zhangcun coal mine in Lu'an coal mining area in Shanxi Province suffered from severe mining-induced stresses with the heading face driven oppositely to an adjacent working face.In this paper,the characteristics of deformation and failure of the entry were investigated in terms of the tempo-spatial relations between heading and working faces through field study and numerical modeling.The three-dimensional(3D) finite difference models were built to investigate stresses,displacements and damages in the surrounding rocks of the entry and the working face.The field study includes selection of reinforcing methods and materials,design parameters,and determination of cable prestress.The monitoring data of entry deformation and stress along the cables during every stage were presented.The state of the reinforced entry was evaluated based on the monitoring data.The results demonstrate that before the heading face of the entry crosses the adjacent working face,the influence of advanced abutment pressure caused by adjacent working face upon the entry is not significant.After they cross each other,however,the lateral abutment pressure will have an evident impact on the entry.The displacement rate of the entry will be greatly increased and reaches a certain value within a certain distance between the heading face and the working face.Then,it will increase again with the presence of secondary mining-induced pressure on the entry when the present working face advances.The fully-grouted cable with short length,high strength and high prestress is an effective way to reinforce the entry suffering from severe mining-induced stresses,which greatly reduces the displacement and failure possibility of the entry.Finally,the principles and recommendations for reinforcing design of entries suffering from severe mining-induced stresses were proposed according to field study,numerical modeling and experiences from other coal mines.Problems encountered in field study and suggestions for reinforcement were also discussed.Hongpu Kang Yongzheng Wu Fuqiang Gao 2011Journal of Rock Mechanics and Geotechnical Engineering2011,3,3:11
4长三角城市群创新合作网络空间演化研究显示文摘以长三角地区27个城市为研究对象,利用各城市2010—2019年联合发明专利授权数据信息,构建长三角地区科技创新合作的本地网络与跨界网络。采用整体网络指标、块模型分析、凝聚子集分析与中心性分析等定量研究手段,探究长三角地区城市群本地网络与跨界网络的演变路径。研究发现:长三角地区城市群科技创新合作的本地网络自2010年来,网络整体联系强度与合作水平提升明显,处于核心区域的城市作为增长的主导者引领着本地网络的发展,但是增长的不均衡也导致核心区域与边缘区域差异的扩大,限制了区域创新网络的进一步完善;2010—2019年间,长三角地区城市群科技创新合作的跨界网络规模急速扩张,区域内各城市与外部的创新合作增长明显,作为增长主导的核心城市积极发挥中间人作用,搭建区域内外部交流合作的管道,推动长三角地区城市群整体创新合作绩效的提升;基于关系地理学理论,未来长三角地区城市群科技创新水平提升的重点应该放在缩小区域内部差距上,提升边缘区域的科技创新能力,强化核心区域的知识流动,通过增强“本地蜂鸣”实现城市群科技创新网络的成熟与完善。王承云 WANG Yongzheng SHEN Zezhou 2021上海师范大学学报(哲学社会科学版)2021,50,5:10
5Identifying heavy hitters in high-speed network monitoring显示文摘Identifying heavy hitters in a network traffic stream is important for a variety of network applications ranging from traffic engineering to anomaly detection such as detection of denial-of-service attacks. Existing methods generally examine newly arriving items in the stream, perform a small number of operations using a small amount of memory, and still provide guarantees on the identifying accuracy. In high-speed network monitoring, the update speed per item is extremely critical. However, so far as we know, there are no identifying algorithms which can provide constant update time (O(1)) in a weighted data stream. In this paper, we present an algorithm named Weighted Lossy Counting (WLC) which is able to identify heavy hitters in a high-speed weighted data stream with constant update time. WLC employs a novel efficient partially ordered data structure which is able to provide a fast per-item update speed while keeping the memory cost relatively low. We compare WLC with state-of-the-art algorithms for finding heavy hitters in real traffic traces. The experimental results show that WLC performs well in accuracy (recall, precision and average relative error) as other algorithms; moreover it has a much higher update speed at the cost of relatively larger memory space used. A theoretical worst-case memory bound of WLC is also derived in this paper; however, experiments with long real traffic traces show that WLC requires much less space than the theoretical bound in practice.ZHANG Yu FANG BinXing ZHANG YongZheng 2010Science China(Information Sciences)2010,53,3:8
6Effect of Ga Addition on Catalytic Performance of PtSnNa/ZSM-5 Catalyst for Propane Dehydrogenation显示文摘PtSnNaGa/ZSM-5 catalysts with different contents of Ga were prepared and characterized by X-ray diffraction (XRD), nitrogen adsorption, hydrogen chemisorption, ammonia temperature-programmed desorption (NH3-TPD), hydrogen temperature-programmed reduction (H2-TPR), and temperature-programmed oxidation (TPO) techniques. The performances of these catalysts for propane dehydrogenation were investigated. The test results indicated that the addition of Ga not only could improve the catalytic stability and propene selectivity, but also could effectively prevent the catalysts from coking. It was found that the PtSnNaGa(0.5 m%)/ZSM-5 catalyst exhibited the best performance in terms of propene selectivity and propane conversion. The high catalytic performance was most probably attributed to the presence of Ga that could strength- en the interaction between metals and the support to stabilize the catalytic active sites.Liu Xuan Zhou Yuming Zhang Yiwei Duan Yongzheng Xue Mengwei Wan Lihui (School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189) 2011China Petroleum Processing & Petrochemical Technology2011,13,4:7
7Effect of cerium addition on catalytic performance of PtSnNa/ZSM-5 catalyst for propane dehydrogenation显示文摘The effect of cerium addition on the catalytic performance of propane dehydrogenation over PtSnNa/ZSM-5 catalyst has been investigated by reaction tests and some physicochemical characterization such as XRD,BET,TEM,XPS,NH 3-TPD,H 2 chemisorption,TPR and TPO techniques.It has been found that with suitable amount of cerium addition,the platinum dispersion increased,while the carbon deposition tended to be eliminated easily.In these cases,the presence of cerium could not only realize the better distribution of metallic particles on the support,but also strengthen the interactions between Sn species and the support.Additionally,XPS spectra confirmed that more amounts of tin could exist in oxidized form,which was advantageous to the reaction.In our experiments,PtSnNaCe(1.1 wt%)/ZSM-5 catalyst exhibited the best catalytic performance.After running the reaction for 750 h,propane conversion was maintained higher than 30% with the corresponding selectivity to propylene of about 97%.Mengwei Xue Yuming Zhou Yiwei Zhang Xuan Liu Yongzheng Duan Xiaoli Sheng 2012Journal of Natural Gas Chemistry2012,21,3:6
8Nitrogen and Phosphorus Dual-Doped Multilayer Graphene as Universal Anode for Full Carbon-Based Lithium and Potassium Ion Capacitors显示文摘Lithium/potassium ion capacitors(LICs/PICs) have been proposed to bridge the performance gap between high-energy batteries and high-power capacitors.However,their development is hindered by the choice,electrochemical performance,and preparation technique of the battery-type anode materials.Herein,a nitrogen and phosphorus dual-doped multilayer graphene(NPG) material is designed and synthesized through an arc discharge process,using low-cost graphite and solid nitrogen and phosphorus sources.When employed as the anode material,NPG exhibits high capacity,remarkable rate capability,and stable cycling performance in both lithium and potassium ion batteries.This excellent electrochemical performance is ascribed to the synergistic effect of nitrogen and phosphorus doping,which enhances the electrochemical conductivity,provides a higher number of ion storage sites,and leads to increased interlayer spacing.Full carbon-based NPG‖LiPF6‖active carbon(AC) LICs and NPG‖KPF6‖AC PICs are assembled and show excellent electrochemical performance,with competitive energy and power densities.This work provides a route for the large-scale production of dual-doped graphene as a universal anode material for high-performance alkali ion batteries and capacitors.Yuting Luan Rong Hu Yongzheng Fang Kai Zhu Kui Cheng Jun Yan Ke Ye Guiling Wang Dianxue Cao 2019Nano-Micro Letters2019,11,2:6
9Effect of aluminum modification on catalytic properties of PtSn-based catalysts supported on SBA-15 for propane dehydrogenation显示文摘The catalytic properties of PtSn-based catalysts supported on siliceous SBA-15 and Al-modified SBA-15, such as Al-incorporated SBA-15 (AlSBA-15) and alumina-modified SBA-15 (Al2O3/SBA-15), for propane dehydrogenation were investigated. Al2O3/SBA-15 was prepared either by an impregnation method using aluminum nitrate aqueous solution, or by the treatment of SBA-15 with a Al(OC3H7)3 solution in anhydrous toluene. N2-physisorption, FT-IR spectroscopy, solid-state 27Al MAS NMR spectroscopy, hydrogen chemisorption, XRF, NH3 temperature-programmed desorption, X-ray photoelectron spectroscopy and TPO were used to characterize these samples. Among these catalysts, the PtSn-based catalyst supported on Al2O3/SBA-15, which was grafted with Al(OC3H7)3, exhibited the best catalytic performance in terms of activity and stability The possible reason was due to the high Pt metal dispersion and/or the strong interactions among Pt, Sn, and the support.Yongzheng Duan Yuming Zhou Yiwei Zhang Xiaoli Sheng Shijian Zhou Zewu Zhang 2012Journal of Natural Gas Chemistry2012,21,2:6
10Microwave-assisted conversion of biomass wastes to pseudocapacitive mesoporous carbon for high-performance supercapacitor显示文摘Developing an efficient approach of transforming biomass waste to functional carbon-based electrode materials applied in supercapacitor offers an important and high value-added practical application due to the abundance and considerable low price of biomass wastes.Herein,a hierarchical carbon functionalized with electrochemical-active oxygen-containing groups was fabricated by microwave treatment from the biomass waste of camellia oleifera.The obtained mesoporous carbon(MAC)owns nanosheet morphology,rich mesoporosity,large surface area(1726 m2/g)and very high oxygenic functionalities(16.2 wt%)with pseudocapacitive activity.Prepared electrode of supercapacitor and tested in 2.0 M H2 SO4,the MAC exhibits an obvious pseudocapacitive activity and achieved a superior supercapacitive performance to that of directly activated carbon(DAC-800)including high specific capacitance(367 F/g vs.298 F/g)and better rate performance(66%vs.44%).The symmetrical supercapacitor based on MAC shows a high capacity of275 F/g,large energy density of 9.55 Wh/kg(at power density of 478 W/kg)and excellent cycling stability with 99%capacitance retention after 10000 continuous charge-discharge,endowing the obtained MAC a promising functional material for electrochemical energy storage.Xiangkun Bo Kun Xiang Yu Zhang Yu Shen Shanyong Chen Yongzheng Wang Mingjiang Xie Xuefeng Guo 2019Journal of Energy Chemistry2019,28,12:6
11Finite-dimensional simple modular Lie superalgebra M显示文摘Lili MA Liangyun CHEN Yongzheng ZHANG 2013Frontiers of Mathematics in China2013,8,2:5
12An antioxidant system through conjugating superoxide dismutase onto metal-organic framework for cardiac repair显示文摘Acute myocardial infarction(AMI)remains a dominant origin of morbidity,mortality and disability worldwide.Increases in reactive oxygen species(ROS)are key contributor to excessive cardiac injury after AMI.Here we developed an immobilized enzyme with Superoxide Dismutase(SOD)activity cross-link with Zr-based metal-organic framework(ZrMOF)(SOD-ZrMOF)for mitigate ROS-caused injury.In vitro and in vivo evidence indicates that SOD-ZrMOF exhibits excellent biocompatibility.By efficiently scavenging ROS and suppressing oxidative stress,SOD-ZrMOF can protect the function of mitochondria,reduce cell death and alleviate inflammation.More excitingly,long-term study using an animal model of AMI demonstrated that SOD-ZrMOF can reduce the infarct area,protect cardiac function,promote angiogenesis and inhibit pathological myocardial remodeling.Therefore,SOD-ZrMOF holds great potential as an efficacious and safe nanomaterial treatment for AMI.Jiacheng Guo Zhenzhen Yang Yongzheng Lu Chunyan Du Chang Cao Bo Wang Xiaoting Yue Zenglei Zhang Yanyan Xu Zhen Qin Tingting Huang Wei Wang Wei Jiang Jinying Zhang Junnan Tang 2022Bioactive Materials2022,7,4:4
13Propane Dehydrogenation on PtSnNa/AlSBA-15 Catalyst:Influence of Tin as a Promoter显示文摘PtSnNa/AlSBA-15 catalysts with different amounts of Sn were prepared for propane dehydrogenation.The catalysts were characterized by XRF,BET,H2 chemisorption,NH3-TPD,H2-TPR,and TPO techniques.Test results indicated that the presence of tin not only modified the acid function and the interfacial character between metal and support,but also reduced the coke deposition effectively.Among these catalysts investigated thereby,the PtSn(0.7%)Na/AlSBA-15 catalyst had the best catalytic performance in terms of propane conversion and stability.With the continuous addition of Sn,more amounts of Sn0 species appeared,which was unfavorable to the reaction.The PtSn(0.7%)Na/AlSBA-15 catalyst was parametrically characterized in order to obtain necessary information to integrate the process operating conditions.A weight hourly space velocity of 3 h-1,a reaction temperature of 610 ℃ and a H2/C3H8 molar ratio of 0.25 were found to be optimum conditions for achieving a higher dehydrogenation activity of the catalyst.Duan Yongzheng Zhou Yuming Zhang Yiwei Sheng Xiaoli Xue Mengwei 2012China Petroleum Processing & Petrochemical Technology2012,14,1:4
14Influence of Alumina Content on Catalytic Performance of PtSn/Al_2O_3/SBA-15 Catalysts for Propane Dehydrogenation显示文摘The alumina-modified SBA-15 (Al2O3/SBA-15) zeolite was prepared in a non-aqueous system by using toluene as the solvent, and was used to support the PtSn-based catalyst for propane dehydrogenation. The BET surface area measurements, hydrogen chemisorption, FT-IR spectroscopy, NH3-TPD, XPS and TPO techniques were used to characterize the catalysts. Test results showed that the addition of alumina not only could modify the acid function of the support but also the structure of the metallic phase, thus affecting their catalytic properties. Among these catalysts studied, the PtSn/Al2O3 (5%)/SBA-15 catalyst exhibited a best catalytic performance in terms of propane conversion and selectivity to propene. The high catalytic performance might be attributed to the relatively good Pt metal dispersion and/or the strong interaction between Pt and Sn species.Zhang Peixin Zhou Yuming Duan Yongzheng Zhang Yiwei Sheng Xiaoli 2012China Petroleum Processing & Petrochemical Technology2012,14,4:4
15Effect of Mischmetal Addition on Catalytic Performance of PtSnNa/ZSM-5 for Propane Dehydrogenation显示文摘The influence of mischmetal addition on physicochemical properties of PtSnNa/ZSM-5 catalyst was studied by means of XRF,H 2 chemisorption,XRD,TPR,NH 3-TPD and TPO techniques.The results showed that the presence of mischmetal had an obvious impact on the catalytic performance of the PtSnNa/ZSM-5 catalyst.A suitable content of mischmetal not only could enhance the interactions between Pt species and the support,but also inhibit the formation of coke during the reaction,thus improving the catalytic activity and stability.In our experiments,when the content of mischmetal was 3m%,the catalyst exhibited best catalytic performance.However,the continuous addition of mischmetal could promote the reduction of Sn species to metallic tin,which was disadvantageous to the reaction.Xue Mengwei Zhou Yuming Huang Li Zhang Yiwei Duan Yongzheng Sheng Xiaoli 2011China Petroleum Processing & Petrochemical Technology2011,13,3:4
16Derivations for even part of finite-dimensional modular Lie superalgebra Ω显示文摘Zhu WEI Yongzheng ZHANG 2012Frontiers of Mathematics in China2012,7,6:3
17Optimization of Four Kinds of Constructed Wetlands Substrate Combination Treating Domestic Sewage显示文摘Based on the static and dynamic experiments, this paper has analyzed the adsorbing capacity for domestic wastewa-ter pollutant (COD, NH4+-N and TP) of four kinds of constructed wetlands substrate which were fly ash, hollow brick crumbs, coal cinder and activated carbon pellets in single and combined condi-tion. In the static experiments, the adsorbing capacity of four sub-strates all grew as the adsorbing dose increased. In adsorbing COD, each substrate’s adsorbing capacity rises with the adsorbing dos-age. Simultaneously, experiments show that all the adsorption of the four kinds of substrate for COD, NH4+-N and TP follows the Freundich Rule. The dynamic experiment demonstrated that the adsorbing capacity of combined substrates is bigger than that of single substrate. Fly ash in combination with small coal cinder adsorbs COD the best, while it takes in NH4+-N and TP the best when working with hollow brick crumbs. The combination of the two raises the removal rates up to 89% and 81% respectively. Given high cost and low adsorbing effect, activated carbon is not a suitable candidate for constructed wetlands substrate.REN Yongzheng ZHANG Beiping LIU Zhen WANG Jin 2007Wuhan University Journal of Natural Sciences2007,12,6:3
18A 150000 t·a^(-1) Post-Combustion Carbon Capture and Storage Demonstration Project for Coal-Fired Power Plants显示文摘1.Introduction Climate change is one of the most severe challenges facing the world today.At present,China produces total annual carbon dioxide(CO_(2))emissions of over 10 billion tonnes,topping the world in this regard.Although coal empowers China’s economic development,its use presents a great challenge to the nation’s desired goals of peaking carbon emissions and achieving carbon neutrality.In this context,the low-carbon utilization of coal is an inevitable trend for future development.Exploring new ways to reduce CO_(2) emissions on a large scale in the utilization of coal—especially during coal-fired power generation—is essential in order for China to achieve carbon neutrality.Qingru Cui Rui Zhao Tiankun Wang Shuai Zhang Yan Huang Yongzheng Gu Dong Xu 2022Engineering2022,8,7:3
19Efficient adsorption to hexavalent chromium by iron oxalate modified D301:Characterization,performance and mechanisms显示文摘Chromium is a common harmful pollutant with high toxicity and low bearing capacity of soil and water.Excellent salinity resistance,a wide pH range,and high regeneration capacity were essential for qualified adsorbents used in removing hexavalent chromium(Cr(VI))from polluted water.Herein,iron oxalate modified weak basic resin(IO@D301)for the removal of Cr(VI)was prepared by the impregnation method.The IO@D301 was characterized by scanning electron microscope(SEM),Fourier transform infrared spectroscopy(FTIR),X-Ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS).Owing to abundant amine,carboxyl groups and iron ions existing on the surface,IO@D301 possesses high adsorption and salinity resistance capacity for Cr(VI).The maximum adsorption capacity of IO301 towards Cr(VI)reached 201.30 mg·g^(-1) at 293 K and a pH of 5.The adsorption equilibrium was well fitted by the Freundlich model,and the adsorption process was described by the pseudofirst-order kinetics model as spontaneous and exothermic.The mechanism may be identified as electrostatic attraction,coordination,and reduction,which was confirmed by FT-IR and X-ray photoelectron spectroscopy.Dongmei Jia Huamin Cai Yongzheng Duan Jiangbao Xia Jia Guo 2021Chinese Journal of Chemical Engineering2021,34,5:3
20地铁施工前邻近砌体建筑物的结构安全性分析显示文摘为确保地铁施工期间邻近建筑物的安全使用,在综合考虑邻近建筑物使用现状、相应规范和受力特点的基础上,运用位移反分析和有限元方法对其进行结构安全分析,并据此确定邻近建筑物变形控制指标。在某地铁车站附属结构施工前,应用该方法对2栋邻近砌体结构建筑物的安全性分析表明:当差异沉降小于10mm时,建筑物上部结构和基础底板能够满足正常使用的要求,根据两栋建筑物分别已有6.59和7.01mm的差异沉降现状,给出2栋建筑物沿既有最大倾斜方向的允许新增差异沉降控制值分别为3和2mm。依此标准,建筑物在附属结构施工结束后结构完好,验证了该工前安全性分析方法的合理性。 Qin, Dongping He, Ping Zhao, Yongzheng Li, Lu 2012中国铁道科学2012,,4:2
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