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| 1 | Effects of landuse change on surface runoff and sediment yield at different watershed scales on the Loess Plateau显示文摘Erosion and sediment yield from large and small watersheds exhibit different laws. Variations in surface runoff and sediment yield because of landuse change in four watersheds of different scales from 1 km2 to 73 km2 were analyzed. Due to reforestation and farmland terracing, surface runoff and sediment yield reduced by 20-100% and 10-100% respectively. Reductions in surface runoff were differed significantly under different precipitation regimes. For the large watershed (73 km2) landuse change had similar effects on surface runoff regardless of changing of precipitation. For the small watershed (1 km2) landuse change had fewer effects on surface runoff under high precipitation. The relative changes of sediment yield in the four watersheds under reforestation and farmland terracing decreased as precipitation increased from 350 mm to 650 mm, then increased as precipitation increased from 650 mm to 870 mm. Where initial forest coverage rate was below 45%, sediment yield decreased dramatically as forest coverage rate increased. Watershed management with aiming at reducing both surface runoff and sediment yield should be conducted both on sloping surfaces and in channels in large watersheds. | ZHANG Xiaoming CAO Wenhong GUO Qingchao WU Sihong | 2010 | International Journal of Sediment Research2010，25，3： | 20 |
| 2 | Simulating the Effect of Hydrate Dissociation on Wellhead Stability During Oil and Gas Development in Deepwater显示文摘It is well known that methane hydrate has been identified as an alternative resource due to its massive reserves and clean property. However, hydrate dissociation during oil and gas development(OGD) process in deep water can affect the stability of subsea equipment and formation. Currently, there is a serious lack of studies over quantitative assessment on the effects of hydrate dissociation on wellhead stability. In order to solve this problem, ABAQUS finite element software was used to develop a model and to evaluate the behavior of wellhead caused by hydrate dissociation. The factors that affect the wellhead stability include dissociation range, depth of hydrate formation and mechanical properties of dissociated hydrate region. Based on these, series of simulations were carried out to determine the wellhead displacement. The results revealed that, continuous dissociation of hydrate in homogeneous and isotropic formations can causes the non-linear increment in vertical displacement of wellhead. The displacement of wellhead showed good agreement with the settlement of overlying formations under the same conditions. In addition, the shallower and thicker hydrate formation can aggravate the influence of hydrate dissociation on the wellhead stability. Further, it was observed that with the declining elastic modulus and Poisson's ratio, the wellhead displacement increases. Hence, these findings not only confirm the effect of hydrate dissociation on the wellhead stability, but also lend support to the actions, such as cooling the drilling fluid, which can reduce the hydrate dissociation range and further make deepwater operations safer and more efficient. | LI Qingchao CHENG Yuanfang ZHANG Huaiwen YAN Chuanliang LIU Yuwen | 2018 | Journal of Ocean University of China2018，17，1： | 11 |
| 3 | Statistical Monitoring of Chemical Processes Based on Sensitive Kernel Principal Components显示文摘核主管部件分析(KPCA ) 方法采用开始的几个核主管部件(KPC ) ,它为过程监视显示正常观察的大多数变化信息,但是不能反映差错信息。在这研究,敏感内核主管部件分析(SKPCA ) 被建议改进监视性能的过程,即,错过了察觉率处理 T2 统计、摆平的预言错误 SPE 统计数值和还原剂的不和。T2 统计数值能被用来沿着每 KPC 直接测量变化并且分析察觉表演以及在一个过程捕获最有用的信息。随沿着每 KPC 的 T2 统计数值的变化率的计算, SKPCA 为进程监视选择敏感内核主管部件。一个模仿的简单系统和田纳西伊斯门过程被采用在联机监视上表明 SKPCA 的效率。结果显示监视表演显著地被改进。 | JIANG Qingchao YAN Xuefeng | 2013 | Chinese Journal of Chemical Engineering2013，21，6： | 10 |
| 4 | Hierarchical Co3O4 porous nanowires as an efficient bifunctional cathode catalyst for long life Li-O2 batteries显示文摘层次公司 < 潜水艇 class= “ a-plus-plus ” > 3 O < 潜水艇 class= “ a-plus-plus ” > 4 多孔的 nanowires (NW ) 用锻烧跟随的一个热水的方法被综合了。当在非水的Li氧电池作为阴极催化剂采用了时,公司<潜水艇class=“ a-plus-plus ”> 3 O <潜水艇class=“ a-plus-plus ”> 4 NW 有效地两个都改进双程的效率和骑车的稳定性,它能被归因于公司的高催化的活动<潜水艇class=“ a-plus-plus ”> 3 O <潜水艇class=“ a-plus-plus ”>为氧减小反应和氧进化反应的 4 NW 分别地在分泌物和费用期间处理。 | Qingchao Liu Yinshan Jiang Jijing Xu Dan Xu Zhiwen Chang Yanbin Yin Wanqiang Liu Xinbo Zhang | 2015 | Nano Research2015，8，2： | 9 |
| 5 | Numerical Analysis of Wellbore Instability in Gas Hydrate Formation During Deep-Water Drilling显示文摘Gas hydrate formation may be encountered during deep-water drilling because of the large amount and wide distribution of gas hydrates under the shallow seabed of the South China Sea. Hydrates are extremely sensitive to temperature and pressure changes, and drilling through gas hydrate formation may cause dissociation of hydrates, accompanied by changes in wellbore temperatures, pore pressures, and stress states, thereby leading to wellbore plastic yield and wellbore instability. Considering the coupling effect of seepage of drilling fluid into gas hydrate formation, heat conduction between drilling fluid and formation, hydrate dissociation, and transformation of the formation framework, this study established a multi-field coupling mathematical model of the wellbore in the hydrate formation. Furthermore, the influences of drilling fluid temperatures, densities, and soaking time on the instability of hydrate formation were calculated and analyzed. Results show that the greater the temperature difference between the drilling fluid and hydrate formation is, the faster the hydrate dissociates, the wider the plastic dissociation range is, and the greater the failure width becomes. When the temperature difference is greater than 7℃, the maximum rate of plastic deformation around the wellbore is more than 10%, which is along the direction of the minimum horizontal in-situ stress and associated with instability and damage on the surrounding rock. The hydrate dissociation is insensitive to the variation of drilling fluid density, thereby implying that the change of the density of drilling fluids has a minimal effect on the hydrate dissociation. Drilling fluids that are absorbed into the hydrate formation result in fast dissociation at the initial stage. As time elapses, the hydrate dissociation slows down, but the risk of wellbore instability is aggravated due to the prolonged submersion in drilling fluids. For the sake of the stability of the wellbore in deep-water drilling through hydrate formation, the drilling fluid with low temperatures should be given priority. The drilling process should be kept under balanced pressures, and the drilling time should be shortened. | ZHANG Huaiwen CHENG Yuanfang LI Qingchao YAN Chuanliang HAN Xiuting | 2018 | Journal of Ocean University of China2018，17，1： | 8 |
| 6 | Regularity of sediment transport and sedimentation during floods in the lower Yellow River,China显示文摘The flood season is the main period of flow,sediment transport,and sedimentation in the lower Yellow River(LYR).Within the flood season,most of the flow,sediment transport,and sedimentation occurs during flood events.Because of the importance of floods in forming riverbeds in the LYR,the regularity of sediment transport and sedimentation during floods in the LYR was studied.Measured daily discharge and sediment transport rate data for the LYR from 1960 to 2006 were used.A total of 299 floods were selected;these floods had a complete evolution of the flood process from the Xiaolangdi to the Lijin hydrological stations.For five hydrological stations(Xiaolangdi,Huayuankou,Gaocun,Aishan,and Lijin),a correlation was first established for floods of different magnitudes between the average sediment transport rate at a given station and the average sediment concentration at the closest upstream station.The results showed that the sediment transport rate at the downstream station was strongly correlated with the inflow(upstream station)sediment concentration during a flood event.A relation then was established between sedimentation in the LYR and the average sediment concentration at the Xiaolangdi station during a flood event.From this relation,the critical sediment concentrations were obtained for absolute erosion,sedimentation equilibrium,and absolute deposition during floods of different magnitudes in the LYR.The results of the current study contribute to a better understanding of the mechanisms of sediment transport and the regularity of sedimentation in the LYR during floods,and provide technical support to guide the joint operation of reservoirs and the regulation of the LYR. | Qingchao Guo Zhao Zheng Liemin Huang Anjun Deng | 2020 | International Journal of Sediment Research2020，35，1： | 6 |
| 7 | Catalytic methanol decomposition to carbon monoxide and hydrogen over Pd/CeO_2-ZrO_2-La_2O_3 with different Ce/Zr molar ratios显示文摘The catalytic behaviors of Pd (1.4 wt%) catalysts supported on CeO2-ZrO2-La2O3 mixed oxides with different Ce/Zr molar ratios were investigated for methanol decomposition. Nitrogen adsorption-desorption (BET), X-ray photoelectron spectroscopy (XPS), H2 temperature-programmed reduction (H2-TPR), X-ray diffraction (XRD) and Pd dispersion analysis were used for their characterization. Pd/Ce0.76Zr0.18 La0.06O1.97 catalyst showed the highest BET surface area, best Pd dispersion capability and strongest metal-support interaction. Moreover, XPS showed that there was lattice defect oxygen or mobile oxygen. According to the result of O 1s measurements the lattice defect oxygen or mobile oxygen helped to maintain Pd in a partly oxidized state and increased the activity for methanol decomposition. The Pd/Ce0.76Zr0.18La0.06O1.97 catalyst exhibited the best activity. A 100% conversion of methanol was achieved at around 260℃, which was about 20-40℃ lower than other | Hairong Wang Yaoqiang Chen Qiulin Zhang Qingchao Zhu Maochu Gong Ming Zhao | 2009 | Journal of Natural Gas Chemistry2009，18，2： | 6 |
| 8 | Modeling sediment transport in the lower Yellow River and dynamic equilibrium threshold value显示文摘A major problem in the lower Yellow River is the insufficient incoming water and excessive sediment supply, which results in serious deposition, continuous rise of the river bed, and austere flood control situation. To understand the sediment transport regularity of the lower Yellow River and determine the relationship between sedimentation, incoming water and sediment, and zone water diversion, a mathematical model of the sediment suitable for the characteristics of the lower Yellow River has been developed. This model is first rated and verified by large quantity of observed data, and it is then used to analyze silting reduction for the lower Yellow River by Xiaolangdi Reservoir’s operation, the relationship between zone water diversion and channel sedimentation, and critical equilibrium of sedimentation in the lower Yellow River. The threshold values of equilibrium of sedimentation in the lower Yellow River are estimated and they suggest that deposition in the lower Yellow River can be effectively reduced by the operation of regulating flow and sediment from Xiaolangdi Reservoir, water-soil conservation, and controlling water diversion along the lower Yellow River. | HU Chunhong GUO Qingchao | 2004 | Science China(Technological Sciences)2004，47，z1： | 6 |
| 9 | Tracking method based on separation and combination of the measurements for radar and IR fusion system显示文摘A new distributed fusion method of radar/infrared (IR) tracking system based on separation and combination of the measurements is proposed by analyzing the influence of rate measurement. The rate information separated from the radar measurements together with measurements of IR form a pseudo vector of IR, and the corresponding filter is designed. The results indicate that the method not only makes a great improvement to the local tracker’s performance, but also improves the global tracking precision efficiently. | Wang Qingchao Wang Wenfei | 2009 | Journal of Systems Engineering and Electronics2009，20，2： | 5 |
| 10 | Polysaccharides in Sipunculus nudus: Extraction Condition Optimization and Antioxidant Activities显示文摘Marine organisms constitute unlimited resource of bioactive substances due to their high biodiversity and represent a valuable source of new compounds. This study optimized the alkali-extraction conditions and antioxidant activities of soluble polysaccharides from the body wall of Sipunculus nudus. The effects of solid-liquid ratio, extraction duration, extraction temperature, and alkali concentration on the yield of S. nudus polysaccharides(SNP) were examined, according to which the optimal combination of extraction parameters was obtained by an orthogonal test. The relative influencing importance of different extraction parameters on the yield of SNP followed the order as solid-liquid ratio > extraction temperature > alkali concentration > extraction duration. The highest extraction yield, 1.98%, was achieved under an optimal extraction condition: temperature 60℃, solid-liquid ratio 1:6 g mL^(-1), duration 5 h, and alkali(Na OH) mass fraction 6%. The in vitro antioxidant activities examination showed that extracted SNP under this optimized condition had strong power in reducing certain hydroxyl and superoxide radical scavenging abilities. The promising results showed that extracted SNP could be a potent natural antioxidant. | ZHANG Qin DONG Lanfang TONG Tong WANG Qingchao XU Mingzhu | 2017 | Journal of Ocean University of China2017，16，1： | 5 |
| 11 | The role of gut microbiota in the pathogenesis of colorectal cancer显示文摘 | Qingchao Zhu Renyuan Gao Wen Wu Huanlong Qin | 2013 | Tumor Biology2013，，3： | 3 |
| 12 | Capability requirements modeling and verification based on fuzzy ontology显示文摘The capability requirements of the command, control, communication, computing, intelligence, surveillance, reconnaissance (C4ISR) systems are full of uncertain and vague information, which makes it difficult to model the C4ISR architecture. The paper presents an approach to modeling the capability requirements with the fuzzy unified modeling language (UML) and building domain ontologies with fuzzy description logic (DL). The UML modeling constructs are extended according to the meta model of Depart- ment of Defense Architecture Framework to improve their domain applicability, the fuzzy modeling mechanism is introduced to model the fuzzy efficiency features of capabilities, and the capability requirement models are converted into ontologies formalized in fuzzy DL so that the model consistency and reasonability can be checked with a DL reasoning system. Finally, a case study of C4ISR capability requirements model checking is provided to demonstrate the availability and applicability of the method. | Qingchao Dong Zhixue Wang Weixing Zhu Hongyue He | 2012 | Journal of Systems Engineering and Electronics2012，23，1： | 3 |
| 13 | Spatial and temporal variations of zooplankton composition and quantity distribution in the upper waters around Nansha Islands显示文摘This study aims to examine spatial and temporal variations of zooplankton species composition,density and biomass distribution and community structure, based on the data obtained from three separate cruises carried out in November 1997, April and July 1999. Results show that 244 species of zooplankton and 8 groups of planktonic larvae were identified, which were dominated by copepods, followed by amphipods, ostracods and medusae. The total species were 201 and 198 for the cruises of November 1997 and July 1999, respectively, and no obvious seasonal variation of species richness was observed. The distribution of zooplankton species richness decreased from pelagic to coastal waters. Average richness of species in each station was higher in the cruises of November 1997(62) and April 1999(61) than in the cruise in July 1999 (56), which was mainly a result from the pelagic or coastal water mass movement made by the monsoon. Zooplankton in the upper waters (0―100 m) around Nansha Islands belonged to the typical tropic pelagic fauna, most of them were pelagic warm-water species, followed by coastal warm-water species and euryhaline warm-water species. The number of dominant species ranged from 5 to 7 in each cruise. No obvious seasonal succession of dominant species was observed. Sagitta enflata, Cypridina nami, Cosmocalanus darwinii, Pleuromamma gracilis and Echinopluteus larva were the main dominant species. The average of zooplankton biomass and density in three cruises were 31, 32, 28 mg·m 3 and 31, 39, 35 ind·m 3, respectively. Copepods were the most abundant, followed by chaetognaths. Zooplankton high biomass distributed mainly in the northwestern waters around Nansha Islands, and generally occurred in the areas of oceanic front and upwelling. The main reason for zooplankton quantity without obvious seasonal variation was the relative steady temperature dynamics in the waters around Nansha Islands. | YIN Jianqiang CHEN Qingchao ZHANG Guxian HUANG Liangmin LI Kaizhi | 2006 | Chinese Science Bulletin2006，51，B12： | 3 |
| 14 | Autonomous process collaboration framework for C4ISR system interoperation显示文摘Interoperability plays an important role in the joint command, control, communication, computer, intelligence, surveillance, reconnaissance(C4 ISR) operations. Coordinating and integrating operational processes to fulfill a common mission are challenged by the ever-changing battlefield and hence requires a cross-organizational process management that produces an autonomous, flexible and adaptable architecture for collaborative process evolution. The traditional business process collaboration pattern is based on the predefined 'public-view' perspective and cannot meet the requirement of the joint task operations. This paper proposes a flexible visibility control mechanism and a dynamic collaboration framework for modeling and generating collaborative processes. The mechanism allows collaborators to define a set of visibility rules to generate different views of the private processes for different collaborations, which gives a great flexibility for the collaboration initiator to decide on an appropriate collaboration pattern. The framework supports collaborators to dynamically and recursively add a new process or even a new organization to an existing collaboration. Moreover, a formal representation of the processes and a set of generation algorithms are provided to consolidate the proposed theory. | Lin Yang Minggang Yu Qingchao Dong | 2017 | Journal of Systems Engineering and Electronics2017，28，6： | 3 |
| 15 | Multimodal process monitoring based on transition-constrained Gaussian mixture model显示文摘Reliable process monitoring is important for ensuring process safety and product quality.A production process is generally characterized bymultiple operation modes,and monitoring thesemultimodal processes is challenging.Most multimodal monitoring methods rely on the assumption that the modes are independent of each other,which may not be appropriate for practical application.This study proposes a transition-constrained Gaussian mixture model method for efficient multimodal process monitoring.This technique can reduce falsely and frequently occurring mode transitions by considering the time series information in the mode identification of historical and online data.This process enables the identified modes to reflect the stability of actual working conditions,improve mode identification accuracy,and enhance monitoring reliability in cases of mode overlap.Case studies on a numerical simulation example and simulation of the penicillin fermentation process are provided to verify the effectiveness of the proposed approach inmultimodal process monitoring with mode overlap. | Shutian Chen Qingchao Jiang Xuefeng Yan | 2020 | Chinese Journal of Chemical Engineering2020，28，12： | 3 |
| 16 | Modeling and verifying So S performance requirements of C4ISR systems显示文摘System-of-systems(So S) engineering involves a complex process of refining high-level So S requirements into more detailed systems requirements and assessing the extent to which the performances of to-be systems may possibly satisfy So S capability objectives. The key issue is how to model such requirements to automate the process of analysis and assessment. This paper suggests a meta-model that defines both functional and nonfunctional features of So S requirements for command and control,communication, computer, intelligence, surveillance reconnaissance(C4ISR) systems. A domain-specific modeling language is defined by extending unified modeling language(UML) constructed of class and association with fuzzy theory in order to model the fuzzy concepts of performance requirements. An efficiency evaluation function is introduced, based on B ′ezier curves,to predict the effectiveness of systems. An algorithm is presented to transform domain models in fuzzy UML into a requirements ontology in description logic(DL) so that requirements verification can be automated with a popular DL reasoner such as Pellet. | Yudong Qi Zhixue Wang Qingchao Dong Hongyue He | 2015 | Journal of Systems Engineering and Electronics2015，26，4： | 2 |
| 17 | Tuning the nucleation and decomposition of Li2O_(2) by fluorine-doped carbon vesicles towards high performance Li-O_(2) batteries显示文摘Li-O_(2) batteries provide an attractive and potential strategy for energy conversion and storage with high specific energy densities.However,large over-potential in oxygen evolution reactions (OER) caused by the decomposition obstacles of Li_(2)O_(2) seriously impedes its electrochemical performances.Herein,a novel N,O,S and F co-doping vesicular carbon was prepared by self-template pyrolysis method and used in LiO_(2) battery to tune the nucleation and decomposition of Li_(2)O_(2).The introduction of F in the carbon matrix with suitable content can regulate the adsorption of intermediates,through which the morphology of Li_(2)O_(2) can be controlled to film,favorable to its decomposition in charge process.The cathode based on the optimized F doped carbon vesicle exhibits improved electrochemical performances including a low over-potential,large capacity and a long-term stability.Density functional theory (DFT) results show that F and C in C–F bond hasve a strong interaction to Li and O in Li_(2)O_(2),respectively,which can enhance the transfer of electrons from Li_(2)O_(2) to the carbon matrix to generate hole polaron and thus accelerate the delithiation and decomposition of Li_(2)O_(2).This work provides a new sight into understanding the mechanism of nucleation and decomposition of Li_(2)O_(2) for the development of high-performance Li-O_(2) batteries. | Shiyu Ma Hongchang Yao Zhongjun Li Qingchao Liu | 2022 | Journal of Energy Chemistry2022，31，7： | 2 |
| 18 | Phytochemical Analysis of Ziziphus jujuba Leaves in Six Cultivars at the Whole Life Stage by High Performance Liquid Chromatography显示文摘 | CUI Xueqin MA Zhongxiao BAI Lu WU Yong GUO Sen LIU Qingchao ZHANG Li HO Chi-Tang BAI Naisheng | 2017 | Chemical Research in Chinese Universities2017，33，5： | 2 |
| 19 | RESEARCHES ON ENVIRONMENTAL CHANGES OF THE YELLOW RIVER BASIN AND LAWS OF WATER AND SEDIMENT TRANSPORTATION显示文摘The major project ’Researches on the environmental changes of the Yellow River Basin and laws of water and sediment transponaion’ wasmanaged jointly by the Institute of Geography of Chinese Academy of Sciences(CAS) and State Planning Commission with the Yellow River ConservancyCommission of Ministry of Water Conservancy of China covering the period of July, 1988-December, 1992. All of the anticipated objectives of the project had been completely reached, and research results of the project were checkedand accepted in July, 1993 in Beijing. The project is charactenzed by thecomprehensiveness in research with systematic and all-around conent throughclosely combining environmotal changes with water and sedimenttransportation in the Yellow River basin, and giving full play to the superiority of the cooperation of multiple disciplines and units.A series of major problemswere well replied in the end. Besides studying some problems of the moment,some basic researches on the prosped of reducing sediments delivered into theYellow River after 2000, the ways to prolonging the lifetime of the current lowerYellow River channel, the program of comprehensive management and development of the drainage basin, etc., were carried out. Moreover, the projecthas outstanding features comparing with other researches on the large rivers inChina, and is uncommon in the field of researches on rivers all over the world. | Ye Qingchao (Institute of Geography, CAS, Beijing 100101People’s Republich of China) | 1995 | Journal of Geographical Sciences1995，5，1： | 2 |
| 20 | Robust Sliding Mode Control Guidance Law for interceptor Based on Wavelet Neural Networks显示文摘 | Da Li Qingchao Wang | 2003 | Control Theory and Applications IEE Proceedings2003，150，3： | 1 |
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