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| 1 | Conjugate Gradient Algorithm in the Four-Dimensional Variational Data Assimilation System in GRAPES显示文摘Minimization algorithms are singular components in four-dimensional variational data assimilation(4DVar).In this paper,the convergence and application of the conjugate gradient algorithm(CGA),which is based on the Lanczos iterative algorithm and the Hessian matrix derived from tangent linear and adjoint models using a non-hydrostatic framework,are investigated in the 4DVar minimization.First,the influence of the Gram-Schmidt orthogonalization of the Lanczos vector on the convergence of the Lanczos algorithm is studied.The results show that the Lanczos algorithm without orthogonalization fails to converge after the ninth iteration in the 4DVar minimization,while the orthogonalized Lanczos algorithm converges stably.Second,the convergence and computational efficiency of the CGA and quasi-Newton method in batch cycling assimilation experiments are compared on the 4DVar platform of the Global/Regional Assimilation and Prediction System(GRAPES).The CGA is 40%more computationally efficient than the quasi-Newton method,although the equivalent analysis results can be obtained by using either the CGA or the quasi-Newton method.Thus,the CGA based on Lanczos iterations is better for solving the optimization problems in the GRAPES 4DVar system. | Yongzhu LIU Lin ZHANG Zhihua LIAN | 2018 | Journal of Meteorological Research2018，32，6： | 9 |
| 2 | The balance of acidity and redox capability over modified CeO_2 catalyst for the selective catalytic reduction of NO with NH_3显示文摘The effect of acidity and redox capability over sulfuric acid-modified CeO_2 catalysts were studied for the selective catalytic reduction of NO_x with NH_3(NH_3-SCR). The deposition of sulfate significantly enhanced the catalytic performance over CeO_2. NO_x conversion over4H_2SO_4/CeO_2 at 230–440 °C was higher than 90%. The strong redox capability of CeO_2 could result in unselective NH_3 oxidation and decrease high temperatures catalytic activity and N_2 selectivity. The deposition of sulfate increased the acidity and weakened the redox capability, and then increased the high temperature NO_x conversion and N_2 selectivity. An appropriate level of acidity also promoted the activity at 190–250 °C over ceria-based catalysts, and with further increase in the acidity, the SCR activity decreased slightly. Weak redox capability lowered the low-temperature catalytic activity. Excellent SCR activity requires a balance of acidity and redox capability on the catalysts. | Zhihua Lian Wenpo Shan Meng Wang Hong He Qingcai Feng | 2019 | Journal of Environmental Sciences2019，31，5： | 6 |
| 3 | A Simple Method for Developing Microsatellite Markers using Amplified Fragments of Inter-simple Sequence Repeat (ISSR)显示文摘 | Chunlan Lian Zhihua Zhou Taizo Hogetsu | 2001 | Journal of Plant Research2001，，3： | 1 |
| 4 | A simple method fordeveloping microsatellite markers using amplified fragments of inter-simple sequence repeat (ISSR) 显示文摘 | Lian Chunlan Zhou Zhihua Hogetsu T | 2001 | Plant Res2001，114，： | 1 |
| 5 | A Simple Method for Developing Microsatellite Markers using Amplified Fragments of Inter-simple Sequence Repeat (ISSR)显示文摘 | Chunlan Lian Zhihua Zhou Taizo Hogetsu | 2001 | Journal of Plant Research2001，，3： | 1 |
| 6 | Temperature stability and microstructure of ultra-high intrinsic coercivity Nd-Fe-B magnets显示文摘The variations of intrinsic coercivity and remanence of sintered Nd-Fe-B magnets with ultra-high intrinsic coercivity were investigated. The results showed that the intrinsic coercivity and remanence declined simultaneously with increasing temperature, but the squareness of the magnets has hardly been changed. The temperature coefficients of remanence (α) and coercivity (β) for the magnets were calculated by two different methods, and the variations of the temperature coefficients and the microstructure of sintered Nd-Fe-B magnets were analyzed. The temperature coefficients of remanence (α) and coercivity (β) for the sintered magnets are very small, and the existence of fine microstructure is necessary to obtain sintered Nd-Fe-B magnets with ultra-high intrinsic coercivity. | HU Zhihua CHENG Xinghua ZHU Minggang LI Wei LIAN Fazeng | 2008 | Rare Metals2008，27，4： | 1 |
| 7 | Improvement of low-temperature catalytic activity over hierarchical Fe-Beta catalysts for selective catalytic reduction of NO_x with NH_3显示文摘Hierarchical Fe-Beta obtained by hydrothermal synthesis exhibited higher low-temperature NH_3-SCR activity than conventional Fe-Beta. In order to identify the main factors leading to the difference in catalytic activity, we investigated the pore structure, acidity and Fe sites of the hierarchical Fe-Beta and conventional Fe-Beta. The enhanced activity of hierarchical Fe-Beta was mainly due to the increase of the quantity of active Fe species. NH_3-TPD and DRIFTS results of NH_3 adsorption clearly verified that hierarchical Fe-Beta had more Lewis acid sites, which is beneficial to the adsorption and activation of NH_3. The H_2-TPR, UV–vis DRS, and EPR results confirmed that the hierarchical Fe-Beta had more isolated active Fe species, which may be associated with that the hierarchical structure introduced more structural defects as ion-exchange sites. Based on the analysis of kinetics experiments and the abovementioned characterizations, it can be concluded that the improvement of NH_3-SCR activity was not due to an intrinsic effect of the specific structural characteristics, but was related to more Fe active sites and better dispersion of Fe species in the hierarchical Fe-Beta. | Na Zhu Zhihua Lian Yan Zhang Wenpo Shan Hong He | 2019 | Chinese Chemical Letters2019，30，4： | 1 |
| 8 | A Simple Method for Developing Microsatellite Markers using Amplified Fragments of Inter-simple Sequence Repeat (ISSR)显示文摘 | Chunlan Lian Zhihua Zhou Taizo Hogetsu | 2001 | Journal of Plant Research2001，，3： | 1 |
| 9 | A simple method for developing microsatellite markers using amplified fragments of Inter-simple sequence repeat 显示文摘 | Lian Chunlan Zhou Zhihua Hogetsu T | 2001 | J Plant Res2001，114，3： | 1 |
| 10 | Effects of impregnation sequence on the NH_(3)-SCR activity and hydrothermal stability of a Ce-Nb/SnO_(2) catalyst显示文摘Hydrothermal stability is crucial for the practical application of deNO_(x)catalyst on diesel vehicles,for the selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR).SnO_(2)-based materials possess superior hydrothermal stability,which is attractive for the development of NH_(3)-SCR catalyst.In this work,a series of Ce-Nb/SnO_(2)catalysts,with Ce and Nb loading on SnO_(2)support,were prepared by impregnation method.It was found that,the NH_(3)-SCR activities and hydrothermal stabilities of the Ce-Nb/SnO_(2)catalysts significantly varied with the impregnation sequences,and the Ce-Nb(f)/SnO_(2) catalyst that firstly impregnated Nb and then impregnated Ce exhibited the best performance.The characterization results revealed that CeNb(f)/SnO_(2)possessed appropriate acidity and redox capability.Furthermore,the strong synergistic effect between Nb and Sn species stabilized the structure and maintained the dispersion of acid sites.This study may provide a new understanding for the effect of impregnation sequence on activity and hydrothermal stability and a new environmental-friendly NH_(3)-SCR catalyst with potential applications for NO_(x)removal from diesel and hydrogenfueled engines. | Ying Zhu Wenpo Shan Zhihua Lian Jingjing Liu Yan Zhang Hong He | 2024 | Journal of Environmental Sciences2024，，4： | 0 |
| 11 | Characteristics and main controlling factors of intra-platform shoal thin-layer dolomite reservoirs:A case study of Middle Permian Qixia Formation in Gaoshiti-Moxi area of Sichuan Basin,SW China显示文摘Based on the study of the distribution of intra-platform shoals and the characteristics of dolomite reservoirs in the Middle Permian Qixia Formation in the Gaoshiti–Moxi area of the Sichuan Basin,SW China,the controlling factors of reservoir development were analyzed,and the formation model of“intra-platform shoal thin-layer dolomite reservoir”was established.The Qixia Formation is a regressive cycle from bottom to top,in which the first member(Qi1 Member)develops low-energy open sea microfacies,and the second member(Qi2 Member)evolves into intra-platform shoal and inter-shoal sea with decreases in sea level.The intra-platform shoal is mainly distributed near the top of two secondary shallowing cycles of the Qi2 Member.The most important reservoir rock of the Qixia Formation is thin-layer fractured-vuggy dolomite,followed by vuggy dolomite.The semi-filled saddle dolomite is common in fracture-vug,and intercrystalline pores and residual dissolution pores combined with fractures to form the effective pore-fracture network.Based on the coupling analysis of sedimentary and diagenesis characteristics,the reservoir formation model of“pre-depositional micro-paleogeomorphology controlling shoal,sedimentary shoal controlling dolomite,penecontemporaneous dolomite benefiting preservation of pores,and late hydrothermal action effectively improving reservoir quality”was systematically established.The“first-order high zone”micro-paleogeomorphology before the deposition of the Qixia Formation controlled the development of large area of intra-platform shoals in Gaoshiti area during the deposition of the Qi2 Member.Shoal facies is the basic condition of early dolomitization,and the distribution range of intra-platform shoal and dolomite reservoir is highly consistent.The grain limestone of shoal facies is transformed by two stages of dolomitization.The penecontemporaneous dolomitization is conducive to the preservation of primary pores and secondary dissolved pores.The burial hydrothermal fluid enters the early dolomite body along the fractures associated with the Emeishan basalt event,makes it recrystallized into medium–coarse crystal dolomite.With the intercrystalline pores and the residual vugs after the hydrothermal dissolution along the fractures,the high-quality intra-platform shoal-type thin-layer dolomite reservoirs are formed.The establishment of this reservoir formation model can provide important theoretical support for the sustainable development of Permian gas reservoirs in the Sichuan Basin. | HE Jiang LIAN Zhihua LUO Wenjun ZHOU Hui XU Huilin HE Puwei Yang Yi LAN Xuemei | 2024 | Petroleum Exploration and Development2024，51，1： | 0 |
| 12 | Interface sites on vanadia-based catalysts are highly active for NO_(x) removal under realistic conditions显示文摘TiO_(2)-supported V_(2)O_(5)catalysts are commonly used in NO_(x)reduction with ammonia due to their robust catalytic performance.Over these catalysts,it is generally considered that the active species are mainly derived from the vanadia species rather than the intrinsic structure of V-O-Ti entities,namely the interface sites.To reveal the role of V-O-Ti entities in NH_(3)-SCR,herein,we prepared TiO_(2)/V_(2)O_(5)catalysts and demonstrated that V-O-Ti entities were more active for NO_(x)reduction under wet conditions than the V sites(V=O)working alone.On the V-O-Ti entities,kinetic measurements and first principles calculations revealed that NH_(3)activation exhibited a much lower energy barrier than that on V=O sites.Under wet conditions,the V-O-Ti interface significantly inhibited the transformation of V=O to V-OH sites thus benefiting NH_(3)activation.Under wet conditions,meanwhile,the migration of NH_(4)^(+)from Ti site neighboring the V-O-Ti interface to Ti site of the V-O-Ti interface was exothermic;thus,V-O-Ti entities together with neighboring Ti sites could serve as channels linking NH_(3)pool and active centers for activation of NH_(4)^(+).This finding reveals that the V-O-Ti interface sites on V-based catalysts play a crucial role in NO_(x)removal under realistic conditions,providing a new perspective on NH_(3)-SCR mechanism. | Zhihui Lv Guangzhi He Wenshuo Zhang Jingjing Liu Zhihua Lian Yang Yang Zidi Yan Guangyan Xu Wenpo Shan Yunbo Yu Hong He | 2024 | Journal of Environmental Sciences2024，，2： | 0 |
| 13 | CeO_(2) doping boosted low-temperature NH3-SCR activity of FeTiOx catalyst:A microstructure analysis and reaction mechanistic study显示文摘FeTiOx has been recognized as an environmental-friendly and cost-effective catalyst for selective catalytic reduction(SCR)of NOx with NH3.Aimed at further improving the low-temperature DeNOx efficiency of FeTiOx catalyst,a simple strategy of CeO_(2) doping was proposed.The low-temperature(<250°C)NH3-SCR activity of FeTiOx catalyst could be dramatically enhanced by CeO2 doping,and the optimal composition of the catalyst was confirmed as FeCe_(0.2)TiOx,which performed a NOx conversion of 90%at ca.200°C.According to X-ray diffraction(XRD),Raman spectra and X-ray absorption fine structure spectroscopy(XAFS)analysis,FeCe_(0.2)TiOx showed low crystallinity,with Fe and Ce species well mixed with each other.Based on the fitting results of extended X-ray absorption fine structure(EXAFS),a unique Ce-O-Fe structure was formed in FeCe_(0.2)TiOx catalyst.The well improved specific surface area and the newly formed Ce-O-Fe structure dramatically contributed to the improvement of the redox property of FeCe_(0.2)TiOx catalyst,which was well confirmed by H2-temperature-programmed reduction(H2-TPR)and in situ XAFS experiments.Such enhanced redox capability could benefit the activation of NO and NH_(3) at low temperatures for NOx removal.The detailed reaction mechanism study further suggested that the facile oxidative dehydrogenation of NH_(3) to highly reactive-NH_(2) played a key role in enhancing the low-temperature NH_(3)-SCR performance of FeCe_(0.2)TiOx catalyst. | Wei Tan Shaohua Xie Wenpo Shan Zhihua Lian Lijuan Xie Annai Liu Fei Gao Lin Dong Hong He Fudong Liu | 2022 | Frontiers of Environmental Science & Engineering2022，16，5： | 0 |
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