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Cyclicity of the Lower Buntsandstein in the eastern part of the Central European Basin:implications for Early Triassic palaeogeography and for geochronological calibration

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Journal of Palaeogeography 2024年第2期13卷 252-292页

作者： Anna Becker Polish geological institute-National research institute 4 Rakowiecka str.00-975 WarsawPoland

Lower Buntsandstein small—scale cycles recognized in the Central European Basin(CEB) are readily used for astrochronological calibration of the Early Triassic time scales,although they are not well studied *** borehole sections from the eastern part of the CEB,forming a south-north transect perpendicular to the basin axis,were studied in terms to better understand the depositional history of the Lower Buntsandstein developed as the Baltic Formation in the studied Polish part of the *** sedimentary facies were recognized,based on lithological and sedimentological investigations of 655.7 m of drill cores from the Otyń IG 1,Gorzów Wielkopolski IG 1 and Kamień Pomorski IG 1 *** facies can be grouped according to a lithological criterion into facies of predominantly siliciclastic lithology(including 9facies types) and facies of predominantly carbonate lithology(including 2 facies types).Facies analysis allowed to distinguish 8 facies associations of:1) alluvial fan,2) playa,3) sandy-muddy coastal plain,4)embayment and distal delta,5) lagoon,6) sand bars or shoals,7) ooidal shoals or bars,and 8) ***-upward(DC) and shallowing-upward(SC) sedimentary cycles were recognized in parts of the Baltic Formation,with DCs dominating in the southernmost located Otyń IG 1,and SCs dominating in Gorz ow Wielkopolski IG 1,located in the axial part of the *** cycles are very *** statistical significance of the sedimentary cycles is relatively low according to Markov-chain analysis conducted with the phpSedistat software of Stanova et al.(2009).Analysis of small—scale cycles performed on well logs of investigated boreholes and additional boreholes in the vicinity of Otyń IG 1,implementing the earlier study of Becker(2005),showed that the correlation of well-log cycles(GR cycles) and sedimentary cycles is not *** cycles can be roughly correlated with lithological carbonate—siliciclastic cycles(c-s cycles),refle

关键词： Triassic Lower Buntsandstein Cyclicity Central European Basin

Petrogenesis and Tectonic Implications of the Early Triassic Nianzi Adakitic Granite Unit in the Yanshan Fold and Thrust Belt:New Constraints from U-Pb Geochronology and Sr-Nd-Hf Isotopes

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 50-66页

作者： ZHANG Huijun WU Chu HE Fubing WANG Biren CUI Yubin LIU Zhenghua YOU Shina DONG Jing Development and research Center of the China geological Survey Beijing 100037China Beijing institute of the geological Survey Beijing 100095China institute of Disaster Prevention LangfangHebei 065201China

The Nianzi granite unit,which includes the Nianzi,Xiaolianghou and Xiawopu granitic intrusions,is a significant component of the northern part of the North China Craton(NCC)and is situated in the Yanshan fold and thrust belt(YFTB).However,there is still debate regarding the tectonic evolutionary history of the YFTB during the late Permian to Triassic period,specifically regarding the timing of subduction and collision between the NCC and the Paleo-Asian *** Nianzi granite unit exhibits unique petrological,geochronological and geochemical signatures that shed light on the tectonic evolutionary history of the *** study presents detailed petrology,whole-rock geochemistry,together with Sr-Nd isotopic,zircon U-Pb dating and Lu-Hf isotopic data of the granites within the Nianzi granite *** findings demonstrate that the granites primarily consist of subhedral K-feldspar,plagioclase,quartz,minor biotite and hornblende,with accessory titanite,apatite,magnetite and *** U-Pb dating indicates that the Xiaolianghou granite was emplaced at 247.5±0.62 ***,the adakitic characteristics of the Nianzi,Xiawopu and Xiaolianghou granitic intrusions,such as high Sr and Ba contents and high ratios of Sr/Y and(La/Yb)N,combined with negative Sr-Nd and Lu-Hf isotopes(87Sr/86Sr)i=0.705681–0.7057433,εNd(t)=−21.98 to−20.97,zirconεHf(t)=−20.26 to−9.92,as well as the I-type granite features of high SiO_(2),Na_(2)O and K_(2)O/Na_(2)O ratios,enriched Rb,K,Sr and Ba,along with depleted Th,U,Nb,Ta,P and Ti,suggest that the Nianzi granitic unit was mainly derived from the partial melting of a thickened lower crust containing hydrous,calc-alkaline to high-K calc-alkaline,mafic to intermediate metamorphic *** light of these parameters,we further integrate our data with previous studies and conclude that the Nianzi granitic unit was generated in a post-collisional extensional environment during the Early Triassic.

关键词： tectonic evolution zircon geochronology Sr-Nd-Hf isotopes Nianzi granite unit Yanshan fold and thrust belt

An Underwater Biomimetic Robot that can Swim,Bipedal Walk and Grasp

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Journal of Bionic Engineering 2024年第3期21卷 1223-1237页

作者： Qiuxuan Wu Liwei Pan FuLin Du ZhaoSheng Wu XiaoNi Chi FaRong Gao Jian Wang Anton A.Zhilenkov School of Automation Hangzhou Dianzi UniversityHangzhou310018China International Joint research Laboratory for Autonomous Robotic Systems Hangzhou310018China GEELY Automotive institute Hangzhou Vocational and Technical CollegeHangzhou310018China institute of Hydrodynamics and Control Processes Sankt-Petersburg Saint Petersburg State Marine Technical UniversitySankt-PetersburgRussia

In developing and exploring extreme and harsh underwater environments,underwater robots can effectively replace humans to complete *** meet the requirements of underwater flexible motion and comprehensive subsea operation,a novel octopus-inspired robot with eight soft limbs was designed and *** robot possesses the capabilities of underwater bipedal walking,multi-arm swimming,and grasping *** closely interact with the underwater seabed environment and minimize disturbance,the robot employs a cable-driven flexible arm for its walking in underwater floor through a bipedal walking *** multi-arm swimming offers a means of three-dimensional spatial movement,allowing the robot to swiftly explore and navigate over large areas,thereby enhancing its ***,the robot’s walking arm enables it to grasp and transport objects underwater,thereby enhancing its practicality in underwater environments.A simplified motion models and gait generation strategies were proposed for two modes of robot locomotion:swimming and walking,inspired by the movement characteristics of octopus-inspired multi-arm swimming and bipedal *** experimental verification,the robot’s average speed of underwater bipedal walking reaches 7.26 cm/s,while the horizontal movement speed for multi-arm swimming is 8.6 cm/s.

关键词： Underwater soft robots Underwater bipedal walking Multi-arm swimming Cable drive

Guidance strategy of motion camouflage for spacecraft pursuit-evasion game

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Chinese Journal of Aeronautics 2024年第3期37卷 312-319页

作者： Jianqing LI Chaoyong LI Yonghe ZHANG Space Information research institute Hangzhou Dianzi UniversityHangzhou 310018China College of Electrical Engineering Zhejiang UniversityHangzhou 310027China Key Lab of Microsatellites Chinese Academy of SciencesShanghai 201210China

This work is inspired by a stealth pursuit behavior called motion camouflage whereby a pursuer approaches an evader while the pursuer camouflages itself against a predetermined *** formulate the spacecraft pursuit-evasion problem as a stealth pursuit strategy of motion camouflage,in which the pursuer tries to minimize a motion camouflage index defined in this *** Euler-Hill reference frame whose origin is set on the circular reference orbit is used to describe the *** on the rule of motion camouflage,a guidance strategy in open-loop form to achieve motion camouflage index is derived in which the pursuer lies on the camouflage constraint line connecting the central spacecraft and *** order to dispose of the dependence on the evader acceleration in the open-loop guidance strategy,we further consider the motion camouflage pursuit problem within an infinite-horizon nonlinear quadratic differential *** saddle point solution to the game is derived by using the state-dependent Riccati equation method,and the resulting closed-loop guidance strategy is effective in achieving motion *** are performed to demonstrate the capabilities of the proposed guidance strategies for the pursuit–evasion game scenario.

关键词： Pursuit-evasion problem Motion camouflage Differential game Guidance strategy Orbit control

Optimized Auxiliary Frequency Control of Wind Farm Based on Piecewise Reduced-order Frequency Response Model

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 791-802页

作者： Xu Zhang Chen Zhao Junchao Ma Long Zhang Dan Sun Chenxu Wang Yan Peng Heng Nian the School of Electrical Engineering Zhejiang UniversityHangzhou 310058China Electric Power research institute of State Grid Zhejiang Electric Power Corporation Hangzhou 310014China

With the increasing wind power penetration in the power system,the auxiliary frequency control(AFC)of wind farm(WF)has been widely *** traditional system frequency response(SFR)model is not suitable for the wind power generation system due to its poor accuracy and *** this paper,a piecewise reduced-order frequency response(PROFR)model is proposed,and an optimized auxiliary frequency control(O-AFC)scheme of WF based on the P-ROFR model is ***,a full-order frequency response model considering the change in operating point of wind turbine is established to improve the *** order to simplify the fullorder model,a P-ROFR model with second-order structure and high accuracy at each frequency response stage is *** on the proposed P-ROFR model,the relationship between the frequency response indexes and the auxiliary frequency controller coefficients is expressed ***,an OAFC scheme with the derived explicit expression as the optimization objective is proposed in order to improve the frequency support capability on the premise of ensuring the full release of the rotor kinetic energy and the full use of the effect of time delay on frequency ***,the effectiveness of the proposed P-ROFR model and the performance of the proposed OAFC scheme are verified by simulation studies.

关键词： Frequency response piecewise reduced-order wind farm auxiliary frequency control

Discrimination of pharmacodynamic components and volatile compounds of Poria cocos cultivated with five different materials based on GC-IMS analysis

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Food Quality and Safety 2024年第1期8卷 135-144页

作者： Yinan Wang Fei Zhou Hui Wang Jinping Zhang Hongxia Xu research institute of Subtropical Forestry Chinese Academy of ForestryHangzhouChina Chun‘an County Thousand-island Lake Forest Farm HangzhouChina

Objectives:The chemical constituents of Poria cocos grown with different substrates vary significantly;thus,identifying and comparing their biomarkers are *** and Methods:Herein,the chemical constituents of Poria cocos obtained with five different substrates were assessed using gas chromatography–ion mobility spectrometry(GC-IMS),high-performance liquid chromatography and multivariate statistical ***:The content of moisture,ash,alcohol-soluble matter,and heavy metals,except for those of the miscellaneous wood Poria cocos,conform to the specifications defined in the Chinese Pharmacopoeia(Edition 2020),and the polysaccharide contents are all greater than 57%.Conclusions:Based on GC-IMS and the established fingerprints,87 compounds were detected,70 of which were identified in each *** statistical analysis revealed seven compounds(two esters,three alcohols,and two aldehydes),which could be considered as potential marker compounds for discrimination.

关键词： Poria cocos cultivation material pharmacodynamic component gas chromatography-ion mobility spectrometry(GC-IMS) volatile compound.

Decentralized Primary Frequency Regulation for Hybrid Multi-terminal Direct Current Power Systems Considering Multi-source Enhancement

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 958-970页

作者： Jialiang Wu Zhen Wang Ruixu Liu Yu Shan Chenxuan Wang the College of Electrical Engineering Zhejiang UniversityHangzhou 310027China the Economic research institute of State Grid Zhejiang Electric Power Co. Ltd.Hangzhou 310016China

Hybrid multi-terminal direct current(MTDC)transmission technology has been a research focus,and primary frequency regulation(FR)improvement in the receiving-end system is one of the problems to be *** paper presents a decentralized primary FR scheme for hybrid MTDC power systems considering multi-source enhancement to help suppress frequency disturbance in the receiving-end *** the converters only need local frequency or DC voltage signal input to respond to system disturbance without communication or a control center,i.e.,a decentralized control *** proposed scheme can activate appropriate power sources to assist in FR in various system disturbance severities with fine-designed thresholds,ensuring sufficient utilization of each power *** better balance FR performance and FR resource participation,an evaluation index is proposed and the parameter optimization problem is further ***,the validity of the proposed scheme is verified by simulations in MATLAB/Simulink.

关键词： Decentralized control scheme primary frequency regulation(FR) rate of change of frequency(ROCOF) system frequency disturbance

OsCPK12 phosphorylates OsCATA and OsCATC to regulate H2O2 homeostasis and improve oxidative stress tolerance in rice

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Plant Communications 2024年第3期5卷 179-196页

作者： Beifang Wang Pao Xue Yingxin Zhang Xiaodeng Zhan Weixun Wu Ping Yu Daibo Chen Junlin Fu Yongbo Hong Xihong Shen Lianping Sun Shihua Cheng Qunen Liu Liyong Cao State Key Laboratory of Rice Biology and Breeding China National Rice Research InstituteHangzhou 311400China Northern Rice research Center of Bao Qing Shuangyashan 155600China Zhejiang Key Laboratory of Super Rice research China National Rice Research InstituteHangzhou 311400China

Calcium-dependent protein kinases(CPKs),the best-characterized calcium sensors in plants,regulate many aspects of plant growth and development as well as plant adaptation to biotic and abiotic ***,how CPKs regulate the antioxidant defense system remains largely *** previously found that impaired function of OsCPK12 leads to oxidative stress in rice,with more H2O2,lower catalase(CAT)activity,and lower ***,we explored the roles of OsCPK12 in oxidative stress tolerance in *** results show that OsCPK12 interacts with and phosphorylates OsCATA and OsCATC at *** of either OsCATA or OsCATC leads to an oxidative stress phenotype accompanied by higher accumulation of *** of the phosphomimetic proteins OsCATAS11D and OsCATCS11D in oscpk12-cr reduced the level of H2O2 ***,OsCATAS11D and OsCATCS11D showed enhanced catalase activity in vivo and in ***12-overexpressing plants exhibited higher CAT activity as well as higher tolerance to oxidative *** demonstrate that OsCPK12 affects CAT enzyme activity by phosphorylating OsCATA and OsCATC at Ser11 to regulate H2O2 homeostasis,thereby mediating oxidative stress tolerance in rice.

关键词： OsCPK12 OsCATs oxidative tolerance Oryza sativa L

Development of a DFN-based probabilistic block theory approach for bench face angle design in open pit mining

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3047-3062页

作者： Jianhua Yan Xiansen Xing Zhihai Li Weida Ni Liuyuan Zhao Chun Zhu Yuanyuan He School of Earth Sciences and Engineering Hohai UniversityNanjing210098China POWERCHINA Huadong Engineering Corporation Limited Hangzhou311122China Zhejiang Huadong Construction Corporation Limited Hangzhou310004China The Seventh geological Brigade of Hubei geological Bureau Yichang443000China

In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation *** this reason,bench face angle,as one of the controlling parameters associated with block instabilities,should be carefully designed for sustainable *** study introduces a discrete fracture network(DFN)-based probabilistic block theory approach for the fast design of the bench face angle.A major advantage is the explicit incorporation of discontinuity size and spatial distribution in the procedure of key blocks *** proposed approach was applied to a granite mine in ***,DFN models were generated from a multi-step modeling procedure to simulate the complex structural characteristics of pit ***,a modified key blocks searching method was applied to the slope faces modeled,and a cumulative probability of failure was obtained for each ***,a bench face angle was determined commensurate with an acceptable risk level of *** simulation results have shown that the number of hazardous traces exposed on the slope face can be significantly reduced when the suggested bench face angle is adopted,indicating an extremely low risk of uncontrolled block instabilities.

关键词： Open pit mine Bench face angle Block theory Probabilistic approach Discrete fracture network modeling Fractured rock slope