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Monazite U-Th-Pb and sericite Rb-Sr dating of the Xiajiadian black shale-hosted gold deposit in the Qinling orogen,central China:Implications for regional gold metallogeny

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Science China Earth Sciences 2024年第8期67卷 2478-2494页

作者： Xueling YU Jianwei LI Xiaoye JIN Shaorui zhao Chongguo he Yunlong ZHU State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Resources China University of GeosciencesWuhan 430074China

The Qinling orogen in central China contains several black shale-hosted gold deposits,but the age of their formation and a possible relation between gold mineralization and regional tectonism remain *** we present results of in situ monazite U-Th-Pb dating and sericite Rb-Sr dating of the Xiajiadian black shale-hosted gold deposit to provide tight constraints on the time of gold deposition and information on the tectonic setting under which the deposit *** Xiajiadian gold deposit is mainly hosted in black shales of the Lower Cambrian Shuigoukou formation,with minor ores contained in sandy conglomerate of the Lower Devonian Xichahe *** ores in the black shales have been intensively oxidized and consist mainly of hematite,goethite,gypsum,quartz,calcite,native gold,and unrecognized iron ***,gold ores in the sandy conglomerate are free of oxidation and thus provide an opportunity to date the formation of the Xiajiadian gold *** ores consist of pyrite,marcasite,sericite,and quartz,which are associated with a variety of accessory minerals,including monazite,apatite,and *** is mainly present as structure-bound ions or nanoparticles in pyrite and marcasite,but minor native gold grains also occur as inclusions in *** is well developed in the ores,and has close textural association with Au-bearing pyrite and *** monazite grains have zoned textures consisting of a core area(Mnz1)and an overgrowth zone(Mnz2).Mnz1 contains 4.8–13 wt.%ThO_(2)and shows large variations in HREE and prominent negative Eu anomalies in the chondrite-normalized REE *** yields common lead-corrected^(208)Pb/^(232)Th dates ranging from 910±10 to416±4 Ma(2σ).These dates are interpreted in terms of a detrital origin for monazite in the core ***2 has much lower ThO_(2)contents of 0.8–1.7 wt.%and shows weak negative Eu anomalies in the chondrite-normalized REE *** yields common lead-corrected^(208)Pb/^(232

关键词： Monazite U-Th-Pb dating Sericite Rb-Sr dating Late Triassic(Norian) Orogenic gold deposit Xiajiadian

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A regression approach for seismic first-break picking

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Petroleum Science 2024年第3期21卷 1584-1596页

作者： Huan Yuan San-Yi Yuan Jie Wu Wen-Jing Sang Yu-he zhao CNPC Key Laboratory of Geophysical Exploration China University of Petroleum(Beijing)Beijing 102249China Research Institute of Petroleum Exploration&Development—Northwest(NWGI) Key Laboratory of reservoir characterization of CNPCPetroChinaLanzhou 730020GansuChina

The picking efficiency of seismic first breaks(FBs)has been greatly accelerated by deep learning(DL)***,the picking accuracy and efficiency of DL methods still face huge challenges in low signal-to-noise ratio(SNR)*** address this issue,we propose a regression approach to pick FBs based on bidirectional long short-term memory(Bi LSTM)neural network by learning the implicit Eikonal equation of 3D inhomogeneous media with rugged topography in the target *** employ a regressive model that represents the relationships among the elevation of shots,offset and the elevation of receivers with their seismic traveltime to predict the unknown FBs,from common-shot gathers with sparsely distributed *** from image segmentation methods which automatically extract image features and classify FBs from seismic data,the proposed method can learn the inner relationship between field geometry and *** addition,the predicted results by the regressive model are continuous values of FBs rather than the discrete ones of the binary *** picking results of synthetic data shows that the proposed method has low dependence on label data,and can obtain reliable and similar predicted results using two types of label data with large *** picking results of9380 shots for 3D seismic data generated by vibroseis indicate that the proposed method can still accurately predict FBs in low SNR *** subsequent stacked profiles further illustrate the reliability and effectiveness of the proposed *** results of model data and field seismic data demonstrate that the proposed regression method is a robust first-break picker with high potential for field application.

关键词： First-break picking Low signal-to-noiseratio Regression BiLSTM Traveltime Geometry Noisy seismic data

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Rice gene OsUGT75A regulates seedling emergence under deep-sowing conditions

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The Crop Journal 2024年第1期12卷 133-141页

作者： Jia zhao Siyu Liu Xiaoqian zhao Zhibo Huang Shan Sun Zixuan Zeng Yongqi he Zhoufei Wang The Laboratory of Seed Science and Technology Guangdong Key Laboratory of Plant Molecular BreedingNational Engineering Research Center of Plant Space BreedingSouth China Agricultural UniversityGuangzhou 510642GuangdongChina

Poor seedling emergence is a challenge for direct seeding of rice under deep-sowing field *** we reveal that UDP-glucosyltransferase OsUGT75A promotes rice seedling emergence under deepsowing conditions by increasing shoot *** of OsUGT75A was higher in the middle regions of the shoot and in shoots under deep-sowing *** of free abscisic acid(ABA)and jasmonates(JA)were higher in shoots of OsUGT75A mutants than in those of wild-type plants,and OsUGT75A mutants were more sensitive to ABA and JA *** shoot length was attributed to higher ABA INSENSITIVE 3(OsABI3)expression and lower JASMONATE-ZIM domain protein(OsJAZ)expression in *** extension by OsUGT75A is achieved mainly by promotion of cell *** elite haplotype of OsUGT75A associated with increased shoot length was identified among indica rice ***75A acts to increase seedling emergence under deep-sowing conditions.

关键词： Abscisic acid Deep-sowing Jasmonic acid Rice Shoot length

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A novel route to enhance high-temperature mechanical property and thermal shock resistance of low-carbon Mgo-C bricks by introducing ZrSiO_(4)

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Journal of Iron and Steel Research International 2024年第6期31卷 1436-1448页

作者： Chun-hui Sun Ling-ling Zhu Hao Yan Wei zhao Jing-xuan Liu Lin Ren Xian-tang zhao Xiao-song tong Shu-wen Yu Beijing Lirr High-Temperature Materials Co. Ltd.Beijing 102211China School of Materials Science and Engineering Henan Province Industrial Technology Research Institute of Resources and MaterialsZhengzhou UniversityZhengzhou 450001HenanChina School of Chemistry and Chemical Engineering Suzhou UniversitySuzhou 234000AnhuiChina

Conventional MgO-C bricks(graphite content>14 wt.%)produce a great deal of greenhouse gas emission,while low-carbon MgO-C bricks have serious thermal shock resistance during high-temperature *** enhance the high-temperature mechanical property and thermal shock resistance of low-carbon MgO-C bricks,a novel route of introducing ZrSiO_(4) powder into low-carbon MgO-C bricks was reported in such refractories with 2 wt.% flaky *** results indicate that the low-carbon MgO-C brick with 0.5 wt.%ZrSiO_(4) addition has the maximum hot modulus of rupture at 1400℃ and the corresponding specimen fired in the carbon embedded atmosphere has the maximum residual strength ratio(98.6%)after three thermal shock *** is found that some needle-like AlON and plate-like Al_(2)O_(3)-ZrO_(2) composites were in situ formed in the matrices after the low-carbon MgO-C bricks were coked at 1400℃,which can enhance the high-temperature mechanical property and thermal shock resistance due to the effect of fiber toughening and particle ***,CO_(2) emission of the newly developed low-carbon MgO-C bricks is reduced by 58.3% per ton steel after using them as the working lining of a 90 t vacuum oxygen decarburization ladle.

关键词： Low-carbon MgO-C brick ZrsiO_(4) Synergistic toughening effect High-temperature mechanical property Thermal shock resistance Vacuum oxygen decarburization ladle

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Adaptive neural network control of a 2-DOF helicopter system considering input constraints and global prescribed performance

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Science China(Information Sciences) 2024年第7期67卷 224-239页

作者： Zhijia zhao Jiale WU Zhijie LIU We he C.L.Philip CheN School of Mechanical and Electrical Engineering Guangzhou University School of Intelligence Science and Technology and Key Laboratory of Intelligent Bionic Unmanned Systems of Ministry of Education University of Science and Technology Beijing School of Computer Science and Engineering South China University of Technology Pazhou Lab

In this study, an adaptive neural network(NN) control is proposed for nonlinear two-degree-offreedom(2-DOF) helicopter systems considering the input constraints and global prescribed ***, radial basis function NN(RBFNN) is employed to estimate the unknown dynamics of the helicopter system. Second, a smooth nonaffine function is exploited to approximate and address nonlinear constraint functions. Subsequently, a new prescribed function is proposed, and an original constrained error is transformed into an equivalent unconstrained error using the error transformation and barrier function transformation methods. The analysis of the established Lyapunov function proves that the controlled system is globally uniformly bounded. Finally, the simulation and experimental results on a constructed Quanser's test platform verify the rationality and feasibility of the proposed control.

关键词： adaptive NN control 2-DOF helicopter global prescribed performance input constraints

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Efficacy and safety of remimazolam in bronchoscopic sedation:A meta-analysis

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World Journal of Clinical Cases 2024年第6期12卷 1120-1129页

作者： Ying Zhou Cheng zhao Yi-Xun Tang Ji-tong Liu Department of Anesthesiology The First Affiliated Hospital of Hunan Normal University(Hunan Provincial People’s Hospital)Changsha 410005Hunan ProvinceChina Department of Anesthesiology Zhangjiajie People's HospitalZhangjiajie 427000Hunan ProvinceChina

BACKGROUND Remimazolam is a new benzodiazepine used for procedural sedation and general *** studies have used remimazolam for bendable *** To assess the safety and efficacy of remimazolam for sedation in patients undergoing bendable bronchoscopy by performing a meta-analysis of randomized controlled trials(RCTs).METHODS We searched the EMBASE,PubMed,Cochrane Library,and Web of Science databases for RCTs on bendable bronchoscopic procedural sedation with remimazolam vs conventional sedatives(CS).RESULTS Five studies with 1080 cases were *** had the same sedation success rate compared with CS[relative risk(RR):1.35,95%CI:0.60-3.05,P=0.474,I2=99.6%].However,remimazolam was associated with a lower incidence of hypotension(RR:0.61;95%CI:0.40-0.95,P=0.027;I2=65.1%)and a lower incidence of respiratory depression(RR:0.50,95%CI:0.33-0.77,P=0.002,I2=42.3%).A subgroup analysis showed a higher success rate of sedation with remimazolam than midazolam(RR:2.45,95%CI:1.76-3.42,Phe incidence of hypotension(RR:0.45,95%CI:0.32-0.64,Phe CS ***,remimazolam has a higher safety profile,with fewer inhibitory effects on respiration and circulation.

关键词： Remimazolam Bronchoscopy Procedural sedation Meta-analysis

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Construction of smart propellant with multi-morphologies

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Defence Technology（防务技术） 2024年第3期33卷 180-185页

作者： Weitao Yang Yuchen Gao Rui Hu Manman Li Fengqi zhao he Jiang Xuan Zhang Xi’an Modern Chemistry Research Institute Xi’an710065China Northwestern Polytechnical University Xi’an710072China

Smart materials,which exhibit shape memory behavior in response to external stimuli,have shown great potential for use in biomedical *** this study,an energetic composite was fabricated using a UV-assisted DIW 3D printing technique and a shape memory material(SMP)as the *** composite has the ability to reduce the impact of external factors and adjust gun propellant combustion *** composition and 3D printing process were delineated,while the internal structure and shape memory performance of the composite material were *** energetic SMP composite exhibits an angle of reversal of 18 s at 70°,with a maximum elongation typically reaching up to 280% of the original length and a recovery length of approximately 105%during ten ***,thermal decomposition and combustion behavior were also demonstrated for the energetic SMP composite.

关键词： Smart material Gun propellants Multi-morphologies Self-regulation

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Biomineralization and mineralization using microfluidics:A comparison study

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 661-669页

作者： Yang Xiao Xiang he Guoliang Ma Chang zhao Jian Chu Hanlong Liu Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing400045China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing400045China School of Civil Engineering Chongqing UniversityChongqing400045China School of Civil and Environmental Engineering Nanyang Technological UniversitySingapore

Biomineralization through microbial process has attracted great attention in the field of geotechnical engineering due to its ability to bind granular materials,clog pores,and seal *** minerals formed by biomineralization are generally the same as that by mineralization,their mechanical behaviors show a significant *** study aims to figure out the differences between biomineralization and mineralization processes by visualizing and tracking the formation of minerals using *** biomineralization and mineralization processes occurred in the Y-shaped sandcontaining microchip that mimics the underground sand *** from different areas in the reaction microchannel of microchips were captured to directly compare the distribution of *** size and numbers from different reaction times were measured to quantify the differences between biomineralization and mineralization processes in terms of crystal *** showed that the crystals were precipitated in a faster and more uncontrollable manner in the mineralization process than that in the biomineralization process,given that those two processes presented similar precipitation *** addition,a more heterogeneous distribution of crystals was observed during the biomineralization *** precipitation behaviors were further explained by the classical nucleation crystal growth *** present microfluidic tests could advance the understanding of biomineralization and provide new insight into the optimization of biocementation technology.

关键词： Microbially induced carbonate precipitation (MICP) Biocementation Crystal Calcium carbonate Nucleation

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Temperature-Dependent Tearing Behavior of Rubber Materials:Characterization and Modeling

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Acta Mechanica Solida Sinica 2024年第2期37卷 316-326页

作者： Qinyuan Yao Feilong Zhang Pan Dong Ziyuan zhao Yi he Weiguo Li Liming Chen State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing400044China College of Aerospace Engineering Chongqing UniversityChongqing400044China

With the increasingly widespread application of rubber in many fields,there is a growing demand for quantitative characterization of temperature-dependent mechanical properties in high-temperature service *** critical tearing energy is an important criterion for determining whether rubber materials will experience tearing instability,while tear strength is a key parameter for rubber materials to resist *** is necessary to quantitatively characterize their evolution with *** theoretical research mainly relies on fitting a large amount of experimental data,which is not convenient for engineering ***,in this work,a temperature-dependent critical tearing energy model is firstly developed based on the force-heat equivalence energy density *** model considers the equivalent relationship between the critical tearing energy required for crack instability propagation and the thermal energy stored in the rubber *** is demonstrated that our model has higher prediction accuracy when compared to other ***,combining with the Griffith fracture theory,temperature-dependent tear strength models applicable to three different crack modes are separately *** models are validated using experimental data for Mode I opening cracks and ModeⅢtearing cracks,and good consistency is ***,a quantitative analysis of the influence of elastic modulus on tear strength at different temperatures is *** work provides a reliable way for predicting temperature-dependent tearing instability behavior and offers beneficial suggestions for improving the tear strength of rubber materials at different temperatures.

关键词： Temperature-dependent Critical tearing energy Tear strength Rubber Theoretical model

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Experimental research on the launching system of auxiliary charge with filter cartridge structure

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Defence Technology（防务技术） 2024年第1期31卷 41-48页

作者： Zi-Jun Chen Ze he Hong-Hao Ma Lu-Qing Wang zhao-Wu Shen CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefeiAnhui230027PR China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefeiAnhui230026PR China

A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the *** combustion chamber of the launching system is divided into two fixed chambers,one is located in the breech chamber,and the other is arranged in the *** breech chamber charge was ignited first,and the charges in the auxiliary chambers were ignited by the high-temperature,highpressure combustible gas trailing the *** this way,the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the *** proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the *** order to obtain some internal ballistic characteristics of the launch system,some critical structure,such as the length of the filter cartridge auxiliary charge,the combustion degree of the propellant in the chamber,and the length of the barrel,are *** experimental results show that with the increased auxiliary charge length,a pressure plateau or even a secondary peak pressure can be formed,which is less than the peak *** projectile velocity increased by 23.57%,14.64%,and 7.65%when the diaphragm thickness was 0 mm,1 mm,and2 mm,*** muzzle velocity of the projectile can be increased by 13.42%by increasing the length of the *** the same charge condition,with the increase of barrel length,the energy utilization rate of propellant increases by 28.64%.

关键词： Interior ballistics Charge structures Launch system Charge design

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