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Observation of Arctic surface currents using data from a surface drifting buoy

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Acta Oceanologica Sinica 2024年第1期43卷 70-79页

作者： hongxia chen Lina Lin Long Fan Wangxiao Yang Yinke Dou Bingrui Li Yan He Bin Kong Guangyu Zuo Na Liu First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Key Laboratory of Marine Science and Numerical Modeling Ministry of Natural ResourcesQingdao 266061China Naval Research Academy Tianjin 300061China College of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan 030024China Polar Research Institute of China Shanghai 443005China

During the 10th Chinese Arctic scientific expedition carried out in the summer of 2019,the surface current in the high-latitude areas of the Arctic Ocean was observed using a self-developed surface drifting buoy,which was initially deployed in the Chukchi Sea.The buoy traversed the Chukchi Sea,Chukchi Abyssal Plain,Mendeleev Ridge,Makarov Basin,and Canada Basin over a period of 632 d.After returning to the Mendeleev Ridge,it continued to drift toward the pole.Overall,the track of the buoy reflected the characteristics of the transpolar drift and Chukchi Slope Current,as well as the inertial flow,cross-ridge surface flow,and even the surface disorganized flow for some time intervals.The results showed that:(1)the transpolar drift mainly occurs in the Chukchi Abyssal Plain,Mendeleev Ridge,and western Canada Basin to the east of the ridge where sea ice concentration is high,and the average northward flow velocity in the region between 79.41°N and 86.32°N was 5.1 cm/s;(2)the average surface velocity of the Chukchi Slope Current was 13.5 cm/s,and while this current moves westward along the continental slope,it also extends northwestward across the continental slope and flows to the deep sea;and(3)when sea ice concentration was less than 50%,the inertial flow was more significant(the maximum observed inertial flow was 26 cm/s,and the radius of the inertia circle was 3.6 km).

关键词： Chinese National Arctic Research Expedition(CHINARE) surface drifting buoy transpolar drift Chukchi Slope Current inertial flow

Influence of O-O formation pathways and charge transfer mediator on lipid bilayer membrane-like photoanodes for water oxidation

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Journal of Energy Chemistry 2024年第6期93卷 526-537,I0013页

作者： Yingzheng Li Shaoqi Zhan Zijian Deng Meng chen Yilong Zhao Chang Liu Ziqi Zhao hongxia Ning Wenlong Li Fei Li Licheng Sun Fusheng Li State Key Laboratory of Fine Chemicals Frontier Science Center for Smart MaterialsDalian University of Technology116024 DalianLiaoningChina Department of Chemistry-Ångström Uppsala UniversityBox 52375120 Uppsal1Sweden Center of Artificial Photosynthesis for Solar Fuels School of ScienceWestlake UniversityHangzhou 310024ZhejiangChina

Inspired by the function of crucial components in photosystemⅡ(PSⅡ),electrochemical and dyesensitized photoelectrochemical(DSPEC)water oxidation devices were constructed by the selfassembly of well-designed amphipathic Ru(bda)-based catalysts(bda=2,2'-bipyrdine-6,6'-dicarbonoxyl acid)and aliphatic chain decorated electrode surfaces,forming lipid bilayer membrane(LBM)-like structures.The Ru(bda)catalysts on electrode-supported LBM films demonstrated remarkable water oxidation performance with different O-O formation mechanisms.However,compared to the slow charge transfer process,the O-O formation pathways did not determine the PEC water oxidation efficiency of the dyesensitized photoanodes,and the different reaction rates for similar catalysts with different catalytic paths did not determine the PEC performance of the DSPECs.Instead,charge transfer plays a decisive role in the PEC water oxidation rate.When an indolo[3,2-b]carbazole derivative was introduced between the Ru(bda)catalysts and aliphatic chain-modified photosensitizer in LBM films,serving as a charge transfer mediator for the tyrosine-histidine pair in PSⅡ,the PEC water oxidation performance of the corresponding photoanodes was dramatically enhanced.

关键词： Water oxidation Rate determine step Dye-sensitized photoelectrochemical cell Charge transfer Artificial photosynthesis

Strategy of preparing SmCo based films with high coercivity and remanence ratio achieved by temperature and chemical optimization

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Journal of Rare Earths 2024年第7期42卷 1289-1297页

作者： Yansong Gong Zhaoguo Qiu Sizhe Liang Xinrui Zheng hongxia Meng Zhigang Zheng Deyang chen Shengfu Yuan Weixing Xia Dechang Zeng J.P.Liu School of Materials Science and Engineering South China University of Technology Zhongshan R&D Center for Materials Surface and Thin Films Technology of the South China University of Technology Gent Materials Surface Technology(Guangdong) Co.Ltd. Institute for Advanced Materials South China Academy of Advanced OptoelectronicsSouth China Normal University Yangjiang Branch Guangdong Laboratory Materials Science and Technology Yangjiang Advanced Alloys Laboratory Laboratory of Rare-Earth Magnetic Functional Materials Ningbo Institute of Material Technology and EngineeringChinese Academy of Sciences Department of Physics University of Texas at Arlington

SmCo based films with excellent intrinsic magnetic properties have promising applications in microelectro-mechanical system（MEMS）.However,due to the complexity of phase composition and uncontrollable crystallization degree of SmCo hard magnetic phase in the film,both the coercivity（Hc） and remanence（Mr） of films are difficult to enhance simultaneously.In this paper,SmCo based films were deposited with a Cr underlayer and capping layer on single crystal Si substrates via magnetron sputtering process.The effects of annealing parameters and Sm/Co atomic ratio on the phase structure and coercivity of films are discussed.By adjusting the Sm/Co atomic ratio from 1:5 to 1:4,Co soft magnetic phase disappears and the single phase SmCo5is obtained,leading to the increase of coercivity of the films from30 to 34 kOe.The influence of deposition temperature and Cu doping on magnetic properties of SmCo based films was investigated.When the deposition temperature increases from room temperature to250℃,the coercivity will further increase from 34 to 51 kOe.However,a severe kink is observed in the demagnetization curves due to the poor exchanged coupling.An analysis of transmission electron microscopy（TEM） confirms that the average size of non-hard magnetic amorphous phase exceeds the effective exchanged coupling length of SmCo5,which contributes to the decoupling and low remanence ratio.Therefore,doping Cu and applying a post-annealing process can significantly improve the crystallization degree of the films.Both the coercivity and the remanence ratio of the demagnetization curves are greatly enhanced.We propose a plausible strategy to prepare the SmCo based films with high coercivity and remanence ratio by temperature and chemical optimization,which can be utilized in high performed MEMS devices.

关键词： Coercivity Crystallization conditions Phase composition Rare earths Remanence ratio SmCo based films

Enhanced photocatalytic performance of Bi_(4)O_(5)Br_(2)with threedimensionally ordered macroporous structure for phenol removal

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Nano Research 2023年第7期16卷 8871-8881页

作者： Kunfeng Zhang hongxia chen Wenbo Pei Hongxing Dai Junshan Li Yongfa Zhu Department of Chemistry Tsinghua UniversityBeijing 100084China College of Environmental Engineering Henan University of TechnologyZhengzhou 450001China Department of Chemistry and Chemical Engineering College of Environmental and Energy EngineeringBeijing University of TechnologyBeijing 100124China Institute for Advanced Study Chengdu UniversityChengdu 610106China

Herein,a series of three-dimensionally ordered macroporous(3DOM)Bi_(4)O_(5)Br_(2)photocatalysts with different macropore sizes were successfully fabricated via a polymethyl methacrylate(PMMA)template method.The photocatalytic activity for phenol degradation over 3DOM Bi_(4)O_(5)Br_(2)first increased and then decreased with the rise in macropore size.Specifically,3DOM Bi_(4)O_(5)Br_(2)-255(macropore diameter ca.170 nm)exhibits the best photocatalytic activity in the static system,which is about 4.5,7.3,and 11.9 times higher than those of bulk Bi_(4)O_(5)Br_(2),Bi_(2)WO_(6),and g-C_(3)N_(4),respectively.Meanwhile,high phenol conversion(75%)is also obtained over 3DOM Bi_(4)O_(5)Br_(2)-255 in the flow system under full spectrum irradiation.Furthermore,3DOM Bi_(4)O_(5)Br_(2)-255 also shows strong mineralization capacity owing to the downward shift of valance band position(0.15 V)as compared with Bi_(4)O_(5)Br_(2).Total organic carbon(TOC)removal rate over 3DOM Bi_(4)O_(5)Br_(2)-255(62%)is much higher than that of Bi_(4)O_(5)Br_(2)(17%).The enhancement in photocatalytic performance of 3DOM Bi_(4)O_(5)Br_(2)-255 is attributable to its better phenol adsorption,O_(2)activation,and charge separation and transfer abilities.This work combines the advantages of 3D structure and surface dangling bonds,providing new possibilities for designing highly efficient photocatalysts for pollutants removal.

关键词： three-dimensionally ordered macroporous structure Bi_(4)O_(5)Br_(2) O_(2)activation photocatalysis degradation

Genetic polymorphisms in genes regulating cell death and prognosis of patients with rectal cancer receiving postoperative chemoradiotherapy

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Cancer Biology & Medicine 2023年第4期20卷 297-316页

作者： hongxia chen Luxi Yin Jie Yang Ningxin Ren Jinna chen Qixuan Lu Ying Huang Yanru Feng Weihu Wang Shulian Wang Yueping Liu Yongwen Song Yexiong Li Jing Jin Wen Tan Dongxin Lin State Key Laboratory of Molecular Oncology Department of Etiology and CarcinogenesisBeijing Key Laboratory for Carcinogenesis and Cancer PreventionNational Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Radiation Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Sun Yat-sen University Cancer Center State Key Laboratory of Oncology in South ChinaGuangzhou 510060China

Objective:The identification of biomarkers for predicting chemoradiotherapy efficacy is essential to optimize personalized treatment.This study determined the effects of genetic variations in genes involved in apoptosis,pyroptosis,and ferroptosis on the prognosis of patients with locally advanced rectal cancer receiving postoperative chemoradiotherapy(CRT).Methods:The Sequenom MassARRAY was used to detect 217 genetic variations in 40 genes from 300 patients with rectal cancer who received postoperative CRT.The associations between genetic variations and overall survival(OS)were evaluated using hazard ratios(HRs)and 95%confidence intervals(CIs)computed using a Cox proportional regression model.Functional experiments were performed to determine the functions of the arachidonate 5-lipoxygenase(ALOX5)gene and the ALOX5 rs702365 variant.Results:We detected 16 genetic polymorphisms in CASP3,CASP7,TRAILR2,GSDME,CASP4,HO-1,ALOX5,GPX4,and NRF2 that were significantly associated with OS in the additive model(P[C]represses ALOX5 transcription and corollary experiments suggested that ALOX5 may promote colon cancer cell growth by mediating an inflammatory response.Conclusions:Polymorphisms in genes regulating cell death may play essential roles in the prognosis of patients with rectal cancer who are treated with postoperative CRT and may serve as potential genetic biomarkers for individualized treatment.

关键词： Rectal neoplasms genetic variation regulated cell death overall survival ALOX5

Ce-promoted Mn/ZSM-5 catalysts for highly efficient decomposition of ozone

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Journal of Environmental Sciences 2021年第5期33卷 219-228页

作者： Linlin Wei hongxia chen Ying Wei Jingbo Jia Runduo Zhang State Key Laboratory of Chemical Resource Engineering Beijing Key Laboratory of Energy Environmental CatalysisBeijing University of Chemical TechnologyBeijing 100029PR China

Manganese oxides supported by ZSM-5 zeolite(Mn/ZSM-5) as well as their further modified by Ce promoter were achieved by simple impregnation method for ozone catalytic decomposition. The yCe20Mn/ZSM-5–81 catalyst with 8% Ce loading showed the highest catalytic activity at relative humidity of 50% and a space velocity of 360 L/(g × hr), giving 93% conversion of 600 ppm O_(3) after 5 hr. Moreover, this sample still maintained highly activity and stability in humid air with 50%–70% relative humidity. Series of physicochemical characterization including X-ray diffraction, temperature-programmed technology(NH_3-TPD and H_(2)-TPR), X-ray photoelectron spectroscopy and oxygen isotopic exchange were introduced to disclose the structure-performance relationship. The results indicated that moderate Si/Al ratio(81) of zeolite support was beneficial for ozone decomposition owing to the synergies of acidity and hydrophobicity. Furthermore, compared with 20 Mn/ZSM-5-81, Ce doping could enhance the amount of low valance manganese(such as Mn^(2+) and Mn^(3+)). Besides, the Ce^(3+)/Ce^(4+) ratio of 8Ce20Mn/ZSM-5-81 sample was higher than that of 4Ce_(2)0 Mn/ZSM-5-81. Additionally, the synergy between the MnO_x and CeO_(2) could easily transfer electron via the redox cycle, thus resulting in an increased reducibility at low temperatures and high concentration of surface oxygen. This study provides important insights to the utilization of porous zeolite with high surface area to disperse active component of manganese for ozone decomposition.

关键词： Manganese oxide ZSM-5 zeolite Ce promoter Adsorbed oxygen Ozone decomposition

Study on Sealing Characteristics of Sliding Seal Assembly of Aircraft Hydraulic Actuator

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Instrumentation 2024年第1期11卷 18-29页

作者： Weinan Li Saixin Shi hongxia Tang Liang chen Jiawei Zhang Hao Tang Jianhua Zhao Shijiazhuang Haishan Industrial Development Corporation Shijiazhuang 050200 China Heavy Machinery Fluid Power Transmission and Control Laboratory Yanshan UniversityQinhuangdao 066004China

The hydraulic actuator,known as the"muscle"of military aircraft,is responsible for flight attitude adjustment,trajectory control,braking turn,landing gear retracting and other actions,which directly affect its flight efficiency and safety.However,the sealing assembly often has the situation of over-aberrant aperture fit clearance or critical over-aberrant clearance,which increases the failure probability and degree of movable seal failure,and directly affects the flight efficiency and safety of military aircraft.In this paper,the simulation model of hydraulic actuator seal combination is established by ANSYS software,and the sealing principle is described.The change curve of contact width and contact pressure of combination seal under the action of high-pressure fluid is drawn.The effects of different oil pressure,fit clearance and other parameters on the sealing performance are analyzed.Finally,the accelerated life test of sliding seal components is carried out on the hydraulic actuator accelerated life test rig,and the surface morphology is compared and analyzed.The research shows that the O-ring is the main sealing element and the role of the check ring is to protect and support the O-ring to prevent damage caused by squeezing into the fit clearance,so the check ring bears a large load and is prone to shear failure.Excessive fit clearance is the main factor affecting the damage of the check ring,and the damage parts are mainly concentrated at the edge of the sealing surface.This paper provides a theoretical basis for the design of hydraulic actuator and the improvement of sealing performance.

关键词： hydraulic actuator contact stress sealing characteristics maximum shear stress

Consistency analysis of accelerated degradation mechanism based on gray theory

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Journal of Systems Engineering and Electronics 2014年第2期25卷 322-331页

作者： Yunxia chen hongxia chen Zhou Yang Rui Kang Yi Yang School of Reliability and Systems Engineering Beihang University

A fundamental premise of an accelerated testing is that the failure mechanism under elevated and normal stress levels should remain the same. Thus, verification of the consistency of failure mechanisms is essential during an accelerated testing. A new consistency analysis method based on the gray theory is pro- posed for complex products. First of all, existing consistency ana- lysis methods are reviewed with a focus on the comparison of the differences among them. Then, the proposed consistency ana- lysis method is introduced. Two effective gray prediction models, gray dynamic model and new information and equal dimensional （NIED） model, are adapted in the proposed method. The process to determine the dimension of NIED model is also discussed, and a decision rule is expanded. Based on that, the procedure of ap- plying the new consistent analysis method is developed. Finally, a case study of the consistency analysis of a reliability enhancement testing is conducted to demonstrate and validate the proposed method.

关键词： enhancement test mechanism consistency gray the-ory smart electricity meter.

Mechanical properties of gangue-containing aluminosilicate based cementitious materials

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Journal of University of Science and Technology Beijing 2006年第2期13卷 183-189页

作者： Huajian Li Henghu Sun Xuejun Xiao hongxia chen Department of Material Science and Engineering Tsinghua University Beijing 100084 China Deportment of Resources China University of Mining ＆ Technology （Beijing） Beijing 100083 China

High performance aluminosilicate based cementitious materials were produced using calcined gangue as one of the major raw materials. The gangue was calcined at 500℃. The main constituent was calcined gangue, fly ash and slag, while alkali-silicate solutions were used as the diagenetic agent. The structure of gangue-containing aluminosilicate based cementitious materials was studied by the methods of IR, NMR and SEM. The results show that the mechanical properties are affected by the mass ratio between the gangue, slag and fly ash, the kind of activator and additional salt. For 28-day curing time, the compressive strength of the sample with a mass proportion of 2：1：1 （gangue： slag： fly ash） is 58.9 MPa, while the compressive strength of the sample containing 80wt% gangue can still be up to 52.3 MPa. The larger K^＋ favors the formation of large silicate oligomers with which AI（OH）4- prefers to bind. Therefore, in Na-K compounding activator solutions more oligomers exist which result in a stronger compressive strength of aluminosilicate-based cementitious materials than in the case of Na-containing activator. The reasons for this were found through IR and NMR analysis. Glauber＇s salt reduces the 3-day compressive strength of the paste, but increases its 7-day and 28-day compressive strengths.

关键词： gangue slag fly ash aluminosilicate based cementitious materials mechanical properties