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| 1 | Zircon U-Pb geochronology,Hf isotopic composition and geological implications of the rhyodacite and rhyodacitic porphyry in the Xiangshan uranium ore field,Jiangxi Province,China显示文摘The Xiangshan uranium ore field is the largest volcanic rock hosted uranium deposit in China.The host rock is a volcanic intrusive complex,including rhyodacite,porphyroclastic lava and late stage sub-volcanic rocks.In this study,zircons from an early stage rhyodacite and a late stage rhyodacite porphyry were dated by SHRIMP and LA-ICP-MS U-Pb methods,and their Hf isotopic compositions were measured by LA-MC-ICP-MS.206Pb/238U ages of 135.1±1.7 and 134.8±1.1 Ma were obtained for the rhyodacite and rhyodacitic porphyry,respectively.These accurate ages indicate that the Xiangshan volcanic-intrusive complex formed in the Early Cretaceous rather than in the Late Jurassic,as concluded in some previous studies.By the Early Cretaceous,the tectonic setting of the area has evolved into a back-arc extensional setting,possibly related to subduction of the paleo-Pacific plate.The close ages of the(early) eruptive rhyodacite and the(late) hypabyssal rhyodacitic porphyry shows that the Xiangshan volcanism was intensive and concentrated in a short time.Zircons from the rhyodacite show negative εHf(t) values of-5.7 to-8.5,with Hf depleted mantle model ages between 1550 and 1720 Ma,whereas zircons from the rhyodacitic porphyry yield εHf(t) values of-6.9 to-10.1 and Hf model ages between 1621 and 1823 Ma.These zircon Hf model ages are similar to the whole rock Nd model ages(1486 to 1911 Ma).Combined with other geochemical characteristics,the Xiangshan rhyodacite and rhyodacitic porphyry may have been derived from partial melting of the Paleo-Mesoproterozoic metamorphic rocks from the Xiangshan basement,without any significant addition of mantle-derived magma.Contribution of basement of this age is also supported by finding a Paleoproterozoic xenocrystic zircon core in the rhyodacite sample. | YANG ShuiYuan JIANG ShaoYong JIANG YaoHui ZHAO KuiDong FAN HongHai | 2010 | Science China Earth Sciences2010，53，10： | 40 |
| 2 | Characteristics of ozone and ozone precursors(VOCs and NOx) around a petroleum refinery in Beijing, China显示文摘A field measurement campaign for ozone and ozone precursors(VOCs and NOx) was conducted in summer 2011 around a petroleum refinery in the Beijing rural region. Three observation sites were arranged, one at southwest of the refinery as the background, and two at northeast of the refinery as the downwind receptors. Monitoring data revealed the presence of serious surface O3 pollution with the characteristics of high average daily mean and maximum concentrations(64.0 and 145.4 ppbV in no-rain days, respectively) and multi-peak diurnal variation. For NOx, the average hourly concentrations of NO2 and NO were in the range of 20.5–46.1 and 1.8–6.4 ppbV, respectively. For VOC measurement, a total of 51 compounds were detected. Normally, TVOCs at the background site was only dozens of ppbC, while TVOCs at the downwind sites reached several hundreds of ppbC. By subtracting the VOC concentrations at background, chemical profiles of VOC emission from the refinery were obtained, mainly including alkanes(60.0% ± 4.3%), alkenes(21.1% ± 5.5%) and aromatics(18.9% ± 3.9%). Moreover, some differences in chemical profiles for the same measurement hours were observed between the downwind sites; the volume ratios of alkanes with low reactivity and those of alkenes with high reactivity respectively showed an increasing trend and a decreasing trend. Finally, based on temporal and spatial variations of VOC mixing ratios, their photochemical degradations and dispersion degradations were estimated to be 0.15–0.27 and 0.42–0.62, respectively, by the photochemical age calculation method, indicating stronger photochemical reactions around the refinery. | Wei Wei Shuiyuan Cheng Guohao Li Gang Wang Haiyang Wang | 2014 | Journal of Environmental Sciences2014，26，2： | 36 |
| 3 | Trends of chemical speciation profiles of anthropogenic volatile organic compounds emissions in China, 2005-2020显示文摘 | Wei WEI Shuxiao WANG Jiming HAO Shuiyuan CHENG | 2014 | Frontiers of Environmental Science & Engineering2014，8，1： | 13 |
| 4 | Two-dimensional materials for synaptic electronics and neuromorphic systems显示文摘Synapses in biology provide a variety of functions for the neural system. Artificial synaptic electronics that mimic the biological neuron functions are basic building blocks and developing novel artificial synapses is essential for neuromorphic computation. Inspired by the unique features of biological synapses that the basic connection components of the nervous system and the parallelism, low power consumption, fault tolerance, self-learning and robustness of biological neural systems, artificial synaptic electronics and neuromorphic systems have the potential to overcome the traditional von Neumann bottleneck and create a new paradigm for dealing with complex problems such as pattern recognition, image classification, decision making and associative learning. Nowadays, two-dimensional(2 D) materials have drawn great attention in simulating synaptic dynamic plasticity and neuromorphic computing with their unique properties. Here we describe the basic concepts of bio-synaptic plasticity and learning, the 2 D materials library and its preparation. We review recent advances in synaptic electronics and artificial neuromorphic systems based on 2 D materials and provide our perspective in utilizing 2 D materials to implement synaptic electronics and neuromorphic systems in hardware. | Shuiyuan Wang David Wei Zhang Peng Zhou | 2019 | Science Bulletin2019，64，15： | 10 |
| 5 | Deformation of freezing water droplets on a cold copper surface显示文摘Freezing processes of water and peanut oil droplets on a cold surface are investigated in this paper. We observed during our experiments that the base surface of a water droplet that is in direct contact with the cold surface keeps its original shape, but the other part of the droplet shows an obvious growth along the direction normal to the base surface. One small protrusion appears on the top of the water droplet at the end of the freezing process. The experimental observations also show that no obvious shape change happens during the freezing of peanut oil droplets. It is postulated that the effects of sur- face tension and volume dilatation resulted from liquid-to-solid phase change cause the shape change and protrusions formation. Based on this postulation, a physical and mathematical model is developed. The results of the model of a water droplet’s freezing process correspond with our experimental observations. The observed phenomenon that frost-growth speed on the protrusion is higher than that on the other part of the water droplet is also analyzed. | WANG Jieteng LIU Zhongliang GOU Yujun ZHANG Xinhua CHENG Shuiyuan | 2006 | Science China(Technological Sciences)2006，49，5： | 9 |
| 6 | Effect of wet flue gas desulfurization(WFGD) on fine particle(PM_(2.5)) emission from coal-fired boilers显示文摘In this study, the characteristics of fine particles before and after wet flue gas desulfurization(WFGD) in three coal-fired heating boilers in northern China were investigated by using a dilution-based emission sampling experimental system. The influences of the WFGD process on the mass and number concentrations as well as the chemical composition of fine particles were analyzed. The removal efficiency of desulfurization processes on particulate matter mass was 30.06%–56.25% for the three study units. The WFGD had a great influence on the size distributions of particle mass concentration and number concentration. A significant increase in the number and mass concentration of particles in the size range of 0.094–0.946 μm was observed. The watersoluble ion content accounted for a very large proportion of PM_(2.5) mass, and its proportion in PM_(2.5) increased from 28.39%–41.08% to 48.96%–61.21% after the WFGD process for the three units. The desulfurizing process also drastically increased the proportion of cation component(Ca^(2+) for unit A, Mg^(2+) for unit B, and Na+for unit C) and the proportion of SO_4^(2-) in PM_(2.5), and it increased the CE/AE values of PM_(2.5) from 0.82–0.98 to 0.93–1.27 for the three study units. | Sen Yao Shuiyuan Cheng Jianbing Li Hanyu Zhang Jia Jia Xiaowei Sun | 2019 | Journal of Environmental Sciences2019，31，3： | 8 |
| 7 | On-board measurements of gaseous pollutant emission characteristics under real driving conditions from light-duty diesel vehicles in Chinese cities显示文摘A total of 15 light-duty diesel vehicles(LDDVs) were tested with the goal of understanding the emission factors of real-world vehicles by conducting on-board emission measurements. The emission characteristics of hydrocarbons(HC) and nitrogen oxides(NOx) at different speeds, chemical species profiles and ozone formation potential(OFP) of volatile organic compounds(VOCs) emitted from diesel vehicles with different emission standards were analyzed. The results demonstrated that emission reductions of HC and NOxhad been achieved as the control technology became more rigorous from Stage I to Stage IV. It was also found that the HC and NOxemissions and percentage of O2 dropped with the increase of speed, while the percentage of CO2 increased. The abundance of alkanes was significantly higher in diesel vehicle emissions, approximately accounting for 41.1%–45.2%, followed by aromatics and alkenes. The most abundant species were propene,ethane, n-decane, n-undecane, and n-dodecane. The maximum incremental reactivity(MIR)method was adopted to evaluate the contributions of individual VOCs to OFP. The results indicated that the largest contributors to O3 production were alkenes and aromatics, which accounted for 87.7%–91.5%. Propene, ethene, 1,2,4-trimethylbenzene, 1-butene, and1,2,3-trimethylbenzene were the top five VOC species based on their OFP, and accounted for 54.0%-64.8% of the total OFP. The threshold dilution factor was applied to analyze the possibility of VOC stench pollution. The majority of stench components emitted from vehicle exhaust were aromatics, especially p-diethylbenzene, propylbenzene, m-ethyltoluene, and p-ethyltoluene. | Gang Wang Shuiyuan Cheng Jianlei Lang Song Li Liang Tian | 2016 | Journal of Environmental Sciences2016，28，8： | 6 |
| 8 | Source apportionment of PM2.5 in Tangshan, China --Hybrid approaches for primary and secondary species apportionment显示文摘这篇论文的目的是在 Tangshan 的城市里为下午 2.5 的主要、第二等的种类的来源分配建议一条混合途径。基于受体的 PMF (积极矩阵因式分解) 与排放库存(EI ) 是综合的为主要种类的来源分配形成第一个混合方法。途径当时是的混合 CAMx-PSAT-CP (有扩展微粒来源分配技术化学药品侧面的全面空气质量模型) 求婚了并且为第二等的种类的来源分配使用了。为 Tangshan 识别的下午 2.5 来源包括了土壤灰尘,冶金工业,发电厂, coalfired 锅炉,车辆,水泥生产,和其它采购原料。PM 2.5 污染是一个地区性的问题,这被显示。在所有识别来源之中,冶金学工业是到开火煤的锅炉,车辆和土壤灰尘跟随的下午 2.5, 的最大的贡献来源。其它来源范畴特别地为第二等的种类的形成为下午 2.5, 起一个关键作用并且喷雾器,和这些另外的来源包括象农业活动那样的非指定的来源,生物资源燃烧,居住排出物,等等。来源分配结果能帮助本地当局做健全政策和规定更好保护公民免受本地人和地区性的下午 2.5 污染的伤害。学习也加亮在下午 2.5 来源的鉴定利用建议混合途径的力量。在这研究使用的技术为进一步的申请显示出可观的诺言到另外的区域以及到识别下午 2.5 的另外的来源范畴。 | Wei WEN Shuiyuan CHENG Lei LIU Gang WANG Xiaoqi WANG | 2016 | Frontiers of Environmental Science & Engineering2016，10，5： | 6 |
| 9 | Characterization of aircraft emissions and air quality impacts of an international airport显示文摘Beijing Capital International Airport(ZBAA) is the world's second busiest airport. In this study, the emissions of air pollutants from aircraft and other sources at ZBAA in 2015 were estimated using an improved method, which considered the mixing layer height calculated based on aircraft meteorological data relay(AMDAR), instead of using the height(915 m)recommended by ICAO. The yearly emissions of NO_x, CO, VOCs, SO_2, and PM_(2.5) at the airport were 8.76 × 10~3, 4.43 × 10~3, 5.43 × 10~2, 4.80 × 10~2, and 1.49 × 10~2 ton/year, respectively. The spatial–temporal distribution of aircraft emissions was systematically analyzed to understand the emission characteristics of aircraft. The results indicated that NOxwas mainly emitted during the take-off and climb phases, accounting for 20.5% and 55.5% of the total emissions. CO and HC were mainly emitted during the taxi phase, accounting for 91.6%and 92.2% of the total emissions. Because the mixing layer height was high in summer, the emissions of aircraft were at the highest level throughout the year. Based on the detailed emissions inventory, four seasons simulation using WRF-CMAQ model was performed over the domain surrounding the airport. The results indicated that the contribution to PM_(2.5) was relatively high in winter; the average impact was about 1.15 μg/m^3 within a radius of1 km around the airport. Meanwhile, the near surroundings and southwest areas of the airport are the most sensitive to PM_(2.5). | Xiaowen Yang Shuiyuan Cheng Jianlei Lang Ran Xu Zhe Lv | 2018 | Journal of Environmental Sciences2018，30，10： | 5 |
| 10 | Distinct potential aerosol masses under different scenarios of transport at a suburban site of Beijing显示文摘In order to evaluate the secondary aerosol formation potential at a suburban site of Beijing,in situ perturbation experiments in a potential aerosol mass(PAM) reactor were carried out in the winter of 2014.The variations of secondary aerosol formation as a function of time,OH exposure,and the concentrations of gas phase pollutants and particles were reported in this study.Two periods with distinct secondary aerosol formation potentials,marked as Period Ⅰ and Period Ⅱ,were identified during the observation.In Period Ⅰ,the secondary aerosol formation potential was high,and correlated well to the air pollutants,i.e.,SO_2,NO_2,and CO.The maximal secondary aerosol formation was observed with an aging time equivalent to about 3 days of atmospheric oxidation.In period Ⅱ,the secondary aerosol formation potential was low,with no obvious correlation with the air pollutants.Meanwhile,the aerosol mass decreased,instead of showing a peak,with increasing aging time.Backward trajectory analysis during the two periods confirmed that the air mass in Period Ⅰwas mainly from local sources,while it was attributed mostly to long distance transport in Period Ⅱ.The air lost its reactivity during the long transport and the particles became highly aged,resulting in a low secondary aerosol formation potential.Our experimental results indicated that the in situ measurement of the secondary aerosol formation potential could provide important information for evaluating the contributions of local emission and long distance transport to the aerosol pollution. | Biwu Chu Yongchun Liu Qingxin Ma Jinzhu Ma Hong He Gang Wang Shuiyuan Cheng Xinming Wang | 2016 | Journal of Environmental Sciences2016，28，1： | 5 |
| 11 | Hierarchical Ni_(3)S_(4)@MoS_(2)nanocomposites as efficient electrocatalysts for hydrogen evolution reaction显示文摘Hydrogen evolution reaction(HER)through water splitting is a promising way to solve the energy shortage.Noble-metal-free HER electrocatalysts with high efficiency is very important for practical applications.Herein,we prepare the Ni_(3)S_(4)@MoS_(2)electrocatalyst on carbon cloth(CC)through a two-step hydrothermal process.The Ni_(3)S_(4)nanorods are uniformly integrated with the MoS_(2)nanosheets,forming a hierarchical structure and heterogeneous interfaces.The fast electron transfer on the interface enhances the kinetics of catalytic reaction.The hierarchical structure provides more exposed active sites.The Ni_(3)S_(4)@MoS_(2)/CC exhibits good catalytic activity and long-term stability for HER.This work provided a practicable strategy to develop efficient electrocatalysts for HER in alkaline media. | Yuxi Ren Shengli Zhu Yanqin Liang Zhaoyang Li Shuilin Wu Chuntao Chang Shuiyuan Luo Zhenduo Cui | 2021 | Journal of Materials Science & Technology2021，，36： | 3 |
| 12 | Effect of Beam Current and Diameter on Electron Probe Microanalysis of Carbonate Minerals显示文摘The effect of operating conditions on the time-dependent X-ray intensity variation is of great importance for the optimal EPMA conditions for accurate determinations of various elements in carbonate minerals. Beam diameters of 0, 1, 2, 5, 10, 15, and 20 μm, and beam currents of 3, 5, 10, 20,and 50 nA were tested. Ca, Mg, Zn, and Sr were found to be more sensitive to electron beam irradiation as compared to other elements, and small currents and large beam diameters minimized the timedependent X-ray intensity variations. We determined the optimal EPMA operating conditions for elements in carbonate: 10 μm and 5 nA for calcite;10 μm and 10 nA for dolomite;5 μm and 10 nA or 10 μm and 20 nA for strontianite;and 20 nA and 5 μm for other carbonate. Elements sensitive to electron beam irradiation should be determined first. In addition, silicate minerals are preferred as standards rather than carbonate minerals. | Xing Zhang Shuiyuan Yang He Zhao Shaoyong Jiang Ruoxi Zhang Jing Xie | 2019 | Journal of Earth Science2019，30，4： | 3 |
| 13 | Catalytic oxidation of carbon monoxide, toluene, and ethyl acetate over the xPd/OMS-2 catalysts: Effect of Pd loading显示文摘在 cryptomelane 类型锰氧化物上支持的 Pd 催化剂八面的分子的筛(OMS-2 ) 被准备。在 xPd/OMS-2 上在碳一氧化物,甲苯,和乙醇醋酸盐的催化氧化上装载的 Pd 的效果被调查了。结果证明装载的 Pd 在与是的 0.5Pd/OMS-2 催化剂超过 Pd 免费的对应物的 xPd/OMS-2 催化剂的物理化学的性质上起一个重要作用最好。为 50% 变换的温度是 25, 240 和 160 迥龔鳥蚈? 蒚? ?? ? | Zhidan Fu Lisha Liu Yong Song Qing Ye Shuiyuan Cheng Tianfang Kang Hongxing Dai | 2017 | Frontiers of Chemical Science and Engineering2017，11，2： | 3 |
| 14 | A monitoring-modeling approach to SO_4^(2-) and NO_3^- secondary conversion ratio estimation during haze periods in Beijing, China显示文摘SO_4^(2-) and NO_3^- are important chemical components of fine particulate matter(PM_(2.5)),especially during haze periods.This study selected two haze episodes in Beijing,China with similar meteorological conditions.A monitoring-modeling approach was developed to estimate the secondary conversion ratios of sulfur and nitrogen based on monitored and simulated concentrations.Measurements showed that in Episode 1(24th–25th October,2014),the concentrations(proportions)of SO_4^(2-) and NO_3^- reached 35.1μg/m^3(14.9%) and 55.0μg/m^3(22.9%),while they reached 14.4μg/m^3(9.3%) and 59.1μg/m^3(38.1%)in Episode 2(26th–27th October,2017).A modeling system was applied to apportion Beijing's SO_4^(2-) and NO_3^- in primary and secondary SO_4^(2-)/NO_3^- emitted from local and regional sources.Thus,secondary conversion contributions considering the local and regional level were defined.The former primarily focused on Beijing atmospheric oxidation ability and the latter mainly considered the existence form of Beijing SO_4^(2-)/NO_3^- under the regional transport impacts.Finally,secondary oxidation ratios were estimated through combining secondary conversion contribution coefficients for simulated and monitored concentrations.At regional level,sulfur oxidation ratios in polluted(clean)days during two sampling periods were0.57–0.72(0.07–0.52)and 0.74–0.80(0.08–0.61),nitrogen oxidation ratios were 0.20–0.29(0.05–0.15)and 0.34–0.38(0.02–0.29),indicating that atmospheric oxidation was enhanced when considering regional transport through 2014–2017.At the local level,sulfur oxidation ratios were 0.66–0.71(0.04–0.48)in haze(clean)days,while nitrogen oxidation ratios were0.16–0.29(0.02–0.16).The atmospheric oxidation ability markedly increased in PM_(2.5)pollution days,but changed only slightly between the two periods. | Xiaoqi Wang Wei Wei Shuiyuan Cheng Chong Zhang Wenjiao Duan | 2019 | Journal of Environmental Sciences2019，31，4： | 3 |
| 15 | Negative Phototropism of Chlorophytum comosum Roots and Their Mechanisms显示文摘The aerial roots of Chlorophytum comosum were grown hydroponically,allowing us to study the performance and mechanism of negative phototropism. The results of this study were as follows. All the adventitious roots and their branch roots bent away from light with a maximum curvature of approximately 88.5°. Blue-violet light prominently induced negative phototropism while red light had no effect. The root cap was the site of photo perception. Roots with shaded or divested root caps exposed to unilateral light showed no negative phototropism,but resumed their original characteristics when the shade was removed or when new root caps grew. The curvature increased when the light intensity ranged 0–110 μmol·m^(-2)·s^(-1). The negative phototropism curvature could be promoted by exogenous CaCl_2 but was inhibited by exogenous LaCl_3; exogenous CaCl_2 could reduce the inhibitory effect of LaCl_3. Unilateral light induced the horizontal transport of IAA from the irradiated side to the shaded side,resulting in an unequal distribution of IAA in both the sides,leading to negative phototropism. The horizontal transport of IAA was promoted by exogenous Ca^(2+) but inhibited by exogenous La^(3+). | CHEN Juan KONG Yu WANG Zhong CHENG Shuiyuan GUYunjie GAN Jie CHEN Peng | 2015 | Horticultural Plant Journal2015，1，1： | 2 |
| 16 | Adsorption performance of CMK-3 and C-FDU-15 in NO removal at low temperature显示文摘CMK-3 and C-FDU-15 samples were synthesized using hard-templating and evaporationinduced self-assembly(EISA)methods,respectively.The pore structures of CMK-3 and CFDU-15 as well as commercial activated carbon were characterized by means of X-ray diffraction,field emission scanning electron microscopy,transmission electron microscopy,and N2 adsorption–desorption.Adsorption of NO was investigated by means of thermogravimetric analysis,temperature-programmed desorption of NO+O2,and in situ diffuse reflectance Fourier transform infrared spectroscopy.The results show that the CMK-3 and C-FDU-15 materials possessed ordered and uniform structures.The coadsorption capacity of NO and O2 decreased in the sequence CMK-3(88.6 mg/g)>C-FDU-15(71.7 mg/g)>AC(25.3 mg/g).There were two main adsorption species on CMK-3 and CFDU-15:nitrite and nitrate.Nitrite is converted to nitrate easily.However,the adsorption species were more complex on AC,with nitrite being the main species.Moreover,CMK-3 and C-FDU-15 exhibit excellent regeneration efficiency compared with AC.The excellent NO adsorption performance of CMK-3 and C-FDU-15 was associated with their ordered mesoporous structures and high surface areas.The research provides more options for NO adsorption in the future. | Runping Wu Qing Ye Kai Wu Shuiyuan Cheng Tianfang Kang Hongxing Dai | 2020 | Journal of Environmental Sciences2020，32，1： | 2 |
| 17 | Role ofβ(FeA1)nanoparticles in abnormal grain growth in the annealing of cast Cu-Al-Mn-Fe shape memory alloys显示文摘In this study,the low-cost production of Cu-AI-Mn-Fe shape memory alloy single crystals exceeding 46 mm by abnormal grain growth was realized only through annealing their cast alloys.The results show that the mis-orientation formed during annealing may be responsible for such abnormal grain growth process.It was con-firmed that this misorientation resulted from the dissolution of bec B(FeAI)nanoparticles during heat treatment at a sufficiently temperature of approximately 1173 K.The rate of migration of the abnormal grain boundary was experimentally measured to be approximately9.3 x 10^-m s^-1within 2 min of the commencement of abnormal grain growth.Additionally,the range of composition of the alloys that can lead to abnormal grain growth was determined.When the Cu-13.0AI-6.5Mn-3.2Fe single crystal close to the[100]direction was deformed to a pre-strain of 12%,full shape recovery happened without any residual strain.At that time,the superelastic strain was approximately 9%.Such a superelastic characteristic remained nearly constant over 50 cycles,showing excellent fatigue resistance.The superelastic properties of the present Cu-13.0AI-6.5Mn-3.2Fe single crystal are compared to those of commercial Ni-Ti-based shape memory alloys.Therefore,it can be considered as a new kind of superelastic material having practical applications.The obtained results should be of great significance in the development of Cu based shape memory alloys.Furthermore,it is expected that a similar microstructure can be designed for the production of more metallic single crystals. | Shuiyuan Yang Xinyu Qing Jixun Zhang Lipeng Guo Shen Hong Mingpei Li Jinbin Zhang Cuiping Wang Xingjun Liu | 2020 | Progress in Natural Science:Materials International2020，30，4： | 2 |
| 18 | Locating Error Considering Dimensional Errors Modeling for Multistation Manufacturing System显示文摘Multistation machining process is widely applied in contemporary manufacturing environment.Modeling of variation propagation in multistation machining process is one of the most important research scenarios.Due to the existence of multiple variation streams,it is challenging to model and analyze variation propagation in a multi-station system.Current approaches to error modeling for multistation machining process are not explicit enough for error control and ensuring final product quality.In this paper,a mathematic model to depict the part dimensional variation of the complex multistation manufacturing process is formulated.A linear state space dimensional error propagation equation is established through kinematics analysis of the influence of locating parameter variations and locating datum variations on dimensional errors,so the dimensional error accumulation and transformation within the multistation process are quantitatively described.A systematic procedure to build the model is presented,which enhances the way to determine the variation sources in complex machining systems.A simple two-dimensional example is used to illustrate the proposed procedures.Finally,an industrial case of multistation machining part in a manufacturing shop is given to testify the validation and practicability of the method.The proposed analytical model is essential to quality control and improvement for multistation systems in machining quality forecasting and design optimization. | ZHANG Faping LU Jiping TANG Shuiyuan SUN Houfang JIAO Li | 2010 | Chinese Journal of Mechanical Engineering2010，23，6： | 2 |
| 19 | Excitation patterns and phonetic identities of Chinese vowels显示文摘After entering the peripheral auditory system, a sound undergoes many significant changes. The excitation pattern describes these changes psychoacoustically as inner expression. This study investigates the relations between excitation patterns and their phonetic qualities for Chinese steady-state vowels. First, the peak positions of the envelope of excitation patterns were measured on a database. The results demonstrated that each Chinese vowel has its own special position for the representative peak of the excitation pattern. Second, to examine the sufficiency of these results, a series of experiments that consisted of identification and evaluation tasks were conducted, in which spectral components of natural isolated vowels were manipulated to create certain excitation patterns. Subjects' responses of these stimuli show that the position of the representative peak of the excitation pattern of a vowel plays a crucial role on its phonetic identity. The results suggest that the phonetic identity of vowels is determined by the position of the representative peak of the excitation pattern evoked by it, and other peaks, if any, do not have phonetic meaning. Additionally, several phenomena about speech perception are discussed on the basis of this study. | YU ShuiYuan | 2009 | Science in China(Series F)2009，52，10： | 2 |
| 20 | Enhanced catalytic performance of Cu-and/or Mn-loaded Fe-Sep catalysts for the oxidation of CO and ethyl acetate显示文摘The Fe-modi fied sepiolite-supported Mn–Cu mixed oxide(Cux Mny/Fe-Sep) catalysts were prepared using the co-precipitation method.These materials were characterized by means of the XRD,N_2 adsorption–desorption,XPS,H_2-TPR,and O_2-TPD techniques,and their catalytic activities for CO and ethyl acetate oxidation were evaluated.The results show that catalytic activities of the Cux Mny/Fe-Sep samples were higher than those of the Cu1/Fe-Sep and Mn2/Fe-Sep samples,and the Mn/Cu molar ratio had a distinct in fluence on catalytic activity of the sample.Among the Cux Mny/Fe-Sep and Cu1Mn2/Sep samples,Cu1Mn2/Fe-Sep performed the best for CO and ethyl acetate oxidation,showing the highest reaction rate and the lowest T50 and T90 of 4.4×10^(-6) mmol·g-1·s-1,110,and 140 °C for CO oxidation,and 1.9×10^(-6) mmol·g-1·s-1,170,and210 °C for ethyl acetate oxidation,respectively.Moreover,the Cu1Mn2/Fe-Sep sample possessed the best lowtemperature reducibility and the lowest temperature of oxygen desorption as well as the highest surface Mn^(4+)/Mn^(3+) and Cu^(2+)/CuO atomic ratios.It is concluded that factors,such as the strong interaction between the Cu or Mn and the Fe-Sep support,good low-temperature reducibility,and good mobility of chemisorbed oxygen species,might account for the excellent catalytic activity of Cu1Mn2/Fe-Sep. | Lisha Liu Yong Song Zhidan Fu Qing Ye Shuiyuan Cheng Tianfang Kang Hongxing Dai | 2017 | Chinese Journal of Chemical Engineering2017，25，10： | 2 |
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