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Determining hydrothermal deactivation mechanisms on Cu/SAPO-34 NH_(3)-SCR catalysts at low-and high-reaction regions:establishing roles of different reaction sites

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Rare Metals 2022年第6期41卷 1899-1910页

作者： Qing-Jin Lin Ming-Ming Pei Pan Yao Shi xu Shu-hao xu Shuang Liu Hai-Di xu Yi Dan Yao-Qiang Chen State Key Laboratory of Polymer Materials Engineering Polymer Research InstituteSichuan UniversityChengdu 610064China Key Laboratory of Green Chemistry and Technology College of ChemistrySichuan UniversityMinistry of EducationChengdu 610064China .Institute of New Energy and Low-Carbon Technology Sichuan UniversityChengdu 610064China Weichai Power Co. LtdWeifang 261061China Sichuan Provincial Automobile Exhaust Purification Engineering Technology Research Center Chengdu 610064China Sichuan Provincial Environmental Protection Environmental Catalytic Materials Engineering Technology Center Chengdu 610064China

Hydrothermal deactivation is a constant chal-lenge in commercial catalytic process aimed at NOx emission control,which may be observed in the low(150-400℃)or high(400-550℃)-reaction *** the best of our knowledge,there is a lack of systematic research regarding the correlation between the reaction sites and the mechanism of hydrothermal degradation at various reaction *** a targeted investigation of this,Cu/zeolite catalysts have been prepared using different amounts of polyvinyl alcohol for adjusting their redox and acid *** catalysts exhibit hydrothermal deactivation in different reaction *** change is observed in the reaction mechanism even with hydrother-mal deactivation,but various reaction sites determine the performance deterioration in the low-and high-reaction *** redox properties and weak acid sites affect the hydrothermal deactivation in the low-reaction region,whereas the moderate/strong acid sites related to the structure mainly influence the hydrothermal deactivation in the high-reaction *** work provides several the-oretical insights for optimizing the hydrothermal stabilities of Cu/zeolite catalysts.

关键词： Deterioration mechanism Bifunctional sites Temperature regions Selective catalytic reduction Cu/zeolite

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Persistent fibrinogen deficiency after snake bite: A case report

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World Journal of Clinical Cases 2021年第33期9卷 10355-10361页

作者： Meng-hao xu Jing Li Liang Han Chao Chen Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina Department of Integrated Traditional Chinese and Western Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina Department of Orthopaedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina Department of Orthopaedics Hefeng Central HospitalEnshi 445800Hubei ProvinceChina

BACKGROUND Venom-induced consumption coagulopathy(VICC)is characterized by coagulation dysfunction accompanied by decreased coagulation factor activity and fibrinogen(FBG)*** report a patient with VICC caused by snake bite who manifested persistent FBG deficiency without abnormal coagulation factor *** information may be helpful in diagnosing and treating *** SUMMARY A 49-year-old man who had been bitten by a snake 13 h previously was admitted to the Emergency Department of our hospital with visible swelling of a finger and a bleeding puncture *** provisional diagnosis was VICC,this being made based on persistent bleeding from the puncture site and subcutaneous *** evidence of coagulation abnormalities,including fibrinolysis,and findings on thromboelastography confirmed *** had persistent afibrinogenemia requiring intravenous infusions of cryoprecipitate and fresh frozen plasma,together with continuous large doses of human *** this treatment,the patient’s right upper limb swelling improved significantly and his subcutaneous hemorrhage *** of his abnormal laboratory findings returned to normal by day *** 6 months’of follow-up,the patient had no further hemorrhagic *** Hemorrhagic snake venom can result in coagulation dysfunction characterized by persistent FBG deficiency without abnormal coagulation factor activity.

关键词： Snake bite Coagulation disorders Venom-induced consumption coagulopathy Fibrinogen deficiency Fibrinogen infusion therapy Case report

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A universal calibration method for eliminating topographydependent current in conductive AFM and its application in nanoscale imaging

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Nano Research 2024年第7期17卷 6509-6517页

作者： Chunlin hao hao xu Shiquan Lin Yaju Zhang Jinmiao He Bei Liu Yuanzheng Zhang Banghao Wu Guozhen Shen Haiwu Zheng Henan Province Engineering Research Center of Smart Micro-nano Sensing Technology and Application School of Physics and ElectronicsHenan UniversityKaifeng 475004China School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 100083China

The topography and electrical properties are two crucial characteristics that determine the roles and functionalities of *** atomic force microscopy(CAFM)is widely recognized for its ability to independently measure the topography and *** increasing trend towards miniaturization in electrical devices and sensors has encouraged an urgent demand for enhancing the accuracy of CAFM ***,when performing CAFM tests on Bi_(0.5)Na_(0.5)TiO_(3)bulk ceramic,it is interesting to observe significant currents related to the *** do insulators exhibit“conductivity”in CAFM testing?Herein,we thoroughly investigated the topography-dependent current during CAFM testing for the first *** on the linear dependence between the current and the first derivative of topography,the calibration method has been proposed to eliminate the topographic *** method is evaluated on Bi_(0.5)Na_(0.5)TiO_(3)bulk ceramic,one-dimensional(1D)ZnO nanowire,twodimensional(2D)NbOI_(2)flake,and biological lotus *** corresponding results of negligible topography-interference current affirm the feasibility and universality of this calibration *** work effectively addresses the challenge of topographic crosstalk in CAFM characterization,thereby preventing the erroneous estimation of the conductivity of any unknown sample.

关键词： conductive atomic force microscopy topographic crosstalk current error calibration method

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Synthesis of Large-Pore ECNU-19 Material （12 × 8-R） via Interlayer- Expansion of HUS-2 Lamellar Silicate

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Chinese Journal of Chemistry 2018年第3期36卷 227-232页

作者： Boting Yang Jin-Gang Jiang hao xu Haihong Wu Peng Wu Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular Engineering East China Normal University North Zhongshan Road 3663 Shanghai 200062 China Department of Chemistry and Biology Beihua University Jiiin Road 15 Jilin Jilin 132013 China

A Yarge-pore ECNU-19 material with unique pore system consisting of 12-ring （12R） pore channels intersected by 8R channels was post-synthesized via interlayer-expansion of HUS-2 lameliar silicate with silylating agent of 1,3-dimethyltetramethoxydisiloxane （DMTMDS）. In consideration of the fact that the HUS-2 precursor possessed a special structure with a malposition of the neighboring layers as well as silicon vacancies on layer surface, a ＂detemplating disassembly - intercalation reassembly - silylation＂ strategy was proposed to realize a successful interlayer-expansion and structural amending. An acid treatment was firstly performed to remove a part of the structure-directing agent molecules, which favored the following intercalation by bulk organic species. The intercalation not only rearranged the relative position of up-down layers but also provided enough interlayer space for the insertion of dimeric silane molecules. Two -OH groups attached to one silicon atom of the silane molecule reacted with two close silanols on the up-surface layer, while the other two -OH groups condensed with two silanols on the down-surface layer, which then connected the two layers via -Si-O-Si- pillars and constructed new 22R pores along o axis and 8R pores along c axis, respectively.

关键词： lamellar silicate HUS-2 interlayer-expansion large-pore material silylation

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FLOW PAST TWO ROTATING CIRCULAR CYLINDERS IN A SIDE-BY-SIDE ARRANGEMENT

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Journal of Hydrodynamics 2009年第2期21卷 143-151页

作者： GUO Xiao-hui LIN Jian-zhong TU Cheng-xu WANG hao-li China Jiliang University Hangzhou 310018 China

Measurements were performed using Particle Image Velocimetry （PIV） to analyze the modification of flow by the combined effects of the rotation and the Reynolds number on the flow past two rotating circular cylinders in a side-by-side-arrangement at a range of 425 〈 Re ≤ 1130,0 ≤α ≤4 （ α is the rotational speed） at one gap spacing of T / d = 1.11 （T and d are the distance between the centers of two cylinders and the cylinder diameter, respectively）. A new Immersed-Lattice Boltzmann Method （ILBM） scheme was used to study the effect of the gap spacing on the flow. The results show that the vortex shedding is suppressed as rotational speed increases. The flow reaches a steady state when the vortex shedding for both cylinders is completely suppressed at critical rotational speed. As the rotational speed further increases, the separation phenomenon in the boundary layers disappears at the attachment rotational speed. The critical rotational speed and attachment rotational speed become small as Reynolds number increases. The absolute rotational speed of cylinders should be large at same critical rotational speed and attachment rotational speed in the case of large Reynolds number. The gap spacing has an important role in changing the pattern of vortex shedding. It is very different in the mechanism of vortex shedding suppression for the flows around two rotating cylinders and single rotating cylinder.

关键词： flow around two rotating cylinders side-by-side arrangement measurement simulation vortex shedding suppression

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Span-based joint entity and relation extraction augmented with sequence tagging mechanism

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Science China(Information Sciences) 2024年第5期67卷 84-98页

作者： Bin JI Shasha LI hao xu Jie YU Jun MA Huijun LIU Jing YANG College of Computer National University of Defense Technology

Span-based joint extraction simultaneously conducts named entity recognition(NER) and relation extraction(RE) in a text span form. However, since previous span-based models rely on span-level classifications, they cannot benefit from token-level label information, which has been proven advantageous for the task. In this paper, we propose a sequence tagging augmented span-based network(STSN), a spanbased joint model that can make use of token-level label information. In STSN, we construct a core neural architecture by deep stacking multiple attention layers, each of which consists of three basic attention *** the one hand, the core architecture enables our model to learn token-level label information via the sequence tagging mechanism and then uses the information in the span-based joint extraction; on the other hand, it establishes a bi-directional information interaction between NER and RE. Experimental results on three benchmark datasets show that STSN consistently outperforms the strongest baselines in terms of F1,creating new state-of-the-art results.

关键词： joint extraction named entity recognition relation extraction span sequence tagging mechanism

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Physical-Layer Secret Key Generation for Dual-Task Scenarios

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China Communications 2024年第7期21卷 252-266页

作者： Yang Lilin Li Guyue Guo Tao xu hao Hu Aiqun School of Cyber Science and Engineering Southeast UniversityNanjing 210096China Purple Mountain Laboratories Nanjing 210096China Department of Electronic and Electrical Engineering University College LondonLondon WC1E 7JEUK National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China

Physical-layer secret key generation(PSKG)provides a lightweight way for group key(GK)sharing between wireless users in large-scale wireless ***,most of the existing works in this field consider only group *** a commonly dual-task scenario,where both GK and pairwise key(PK)are required,traditional methods are less suitable for direct *** the first time,we discover a security issue with traditional methods in dual-task scenarios,which has not previously been *** propose an innovative segment-based key generation method to solve this security *** do not directly use PK exclusively to negotiate the GK as traditional ***,we generate GK and PK separately through segmentation which is the first solution to meet *** also perform security and rate *** is demonstrated that our method is effective in solving this security issue from an information-theoretic *** rate results of simulation are also consistent with the our rate derivation.

关键词： dual-task scenario information-theoretic security physical layer security secret group key generation

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Influences of oxide content and sintering temperature on microstructures and mechanical properties of intragranular-oxide strengthened iron alloys prepared by spark plasma sintering

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International Journal of Minerals,Metallurgy and Materials 2023年第9期30卷 1748-1755页

作者： Deyin Zhang xu hao Baorui Jia haoyang Wu Lin Zhang Mingli Qin xuanhui Qu Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China

How to increase strength without sacrificing ductility has been developed as a key goal in the manufacture of high-performance metals or alloys. Herein, the double-nanophase intragranular yttrium oxide dispersion strengthened iron alloy with high strength and appreciable ductility was fabricated by solution combustion route and subsequent spark plasma sintering, and the influences of yttrium oxide content and sintering temperature on microstructures and mechanical properties were investigated. The results show at the same sintering temperature,with the increase of yttrium oxide content, the relative density of the sintered alloy decreases and the strength increases. For Fe–2wt%Y_(2)O_(3)alloy, as the sintering temperature increases gradually, the compressive strength decreases, while the strain-to-failure increases. The Fe–2wt%Y_(2)O_(3)alloy with 15.5 nm Y_(2)O_(3)particles uniformly distributed into the 147.5 nm iron grain interior sintered at 650℃ presents a high ultimate compressive strength of 1.86 GPa and large strain-to-failure of 29%. The grain boundary strengthening and intragranular second-phase particle dispersion strengthening are the main dominant mechanisms to enhance the mechanical properties of the alloy.

关键词： oxide dispersion strengthening spark plasma sintering microstructure and properties strengthening mechanism

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Hybrid bonding of GaAs and Si wafers at low temperature by Ar plasma activation

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Journal of Semiconductors 2024年第4期45卷 69-75页

作者： Rui Huang Zhiyong Wang Kai Wu hao xu Qing Wang Yecai Guo School of Electronic and Information Engineering Wuxi UniversityWuxi 214105China Institute of Advanced Technology on Semiconductor Optics&Electronics Institute of Laser EngineeringBeijing University of TechnologyBeijing 100124China

High-quality bonding of 4-inch GaAs and Si is achieved using plasma-activated bonding *** influence of Ar plasma activation on surface morphology is *** the annealing temperature is 300℃,the bonding strength reaches a maximum of 6.2 *** addition,a thermal stress model for GaAs/Si wafers is established based on finite element analysis to obtain the distribution of equivalent stress and deformation variables at different *** shape varia-tion of the wafer is directly proportional to the annealing *** an annealing temperature of 400℃,the maximum protrusion of 4 inches GaAs/Si wafers is 3.6 *** interface of GaAs/Si wafers is observed to be dense and defect-free using a transmission electron *** characterization of interface elements by X-ray energy dispersion spectroscopy indi-cates that the elements at the interface undergo mutual diffusion,which is beneficial for improving the bonding strength of the *** is an amorphous transition layer with a thickness of about 5 nm at the bonding *** preparation of Si-based GaAs heterojunctions can enrich the types of materials required for the development of integrated circuits,improve the performance of materials and devices,and promote the development of microelectronics technology.

关键词： plasma-activated bonding bonding strength thermal stress model mutual diffusion

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Automatic mapping of gully from satellite images using asymmetric non-local LinkNet: A case study in Northeast China

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International Soil and Water Conservation Research 2024年第2期12卷 365-378页

作者： Panpan Zhu hao xu Ligang Zhou Peixin Yu Liqiang Zhang Suhong Liu College of Computer Sciences and Technology Chongqing University of Posts and TelecommunicationsChongqing Engineering Research Center for Spatial Big Data Intelligent TechnologyChongqing400065China College of Environment and Ecology Chongqing UniversityChongqing400044China Chongqing Municipal Ecological and Environmental Monitoring Center Chongqing401120China Beijing Key Laboratory of Environmental Remote Sensing and Digital Cities Faculty of Geographical ScienceBeijing Normal UniversityBeijing100875China China National Environmental Monitoring Centre Beijing100012China

Gully erosion can lead to the destruction of farmland and the reduction in crop *** mapping from remote sensing images is critical for quickly obtaining the distribution of gullies at regional scales and arranging corresponding prevention and control *** narrow and irregular shapes and similar colors to the surrounding farmland make mapping erosion gullies in sloping farmland from remote sensing images *** implement gully erosion mapping,we developed a small training samples-oriented lightweight deep leaning model,called asymmetric non-local LinkNet(ASNL-LinkNet).The ASNL-LinkNet integrates global context information through an asymmetric non-local operation and conducts multilayer feature fusion to improve the robustness of the extracted *** results show that the proposed ASNL-LinkNet achieves the best performance when compared with other deep learning *** quantitative evaluation results in the three test areas show that the F1-score of erosion gully recognition varies from 0.62 to *** study provides theoretical reference and practical guidance for monitoring erosion gullies on slope farmland in the black soil region of Northeast China.

关键词： Gully erosion mapping High-resolution satellite images Deep learning Black soil

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