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Geochemistry of Triassic Siliceous Rocks of the Muyinhe Formation in the Changning-Menglian Belt of Southwest China

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Journal of Earth Science 2016年第3期27卷 403-411页

作者： Tsuyoshi Ito xin qian Qinglai Feng State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Stratigraphy and Tectonics Research Group Institute of Geology and Geoinformation Geological Survey of Japan School of Earth Sciences China University of Geosciences

The Changning-Menglian belt, distributed over southwestern Yunnan Province in Southwest China, contains oceanic rocks that are considered to be remnants of the Paleotethys. This study observed Triassic siliceous rocks of the Muyinhe Formation in the Changning-Menglian belt and analyzed their geochemistry. The samples have high concentrations of SiO2（81.65 wt.%–88.38 wt.%; average： 84.99 wt.%±2.14 wt.%）. Most of the samples were plotted in the non-hydrothermal field on the Al-Fe-Mn diagram. Most of the samples were plotted in the continental margin field on the Fe2O3/TiO2-Al2O3/（Al2O3＋Fe2O3） and（La/Ce）N-Al2O3/（Al2O3＋Fe2O3） diagrams. Moreover, the samples show a flat REE（rare earth element） pattern normalized to NASC（North America shale composite）. These geochemical results, in addition to the lack of rhythmical bedding of the siliceous rocks, strongly suggest that the siliceous rocks are unlikely to represent pelagic deposits. Although previous studies have suggested that the siliceous rocks are pelagic deposits, the present results indicate that the extent of the pelagic ocean basins in the Paleotethys during the Triassic is probably less than previously believed. These non-pelagic deposits may represent the closure stage of the Paleotethys.

关键词： geochemistry Triassic siliceous rock Paleotethys Muyinhe Formation Changning-Menglian belt

Repairing of rutin to the toxicity of combined F-53B and chromium pollution on the biofilm formed by Pseudomonas aeruginosa

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Journal of Environmental Sciences 2023年第5期127卷 158-168页

作者： Yunhao Zhang Yi qian ming Zhang Weichuan Qiao Department of Environmental Engineering College of Biology and the EnvironmentNanjing Forestry UniversityNanjing 210037China

The wastewater discharge from the process of chrome plating,which contains 6:2 chlorinated polyfluorinated ether sulfonate(F-53B)and chromium(Cr),may be toxic to *** this study we found that the biofilm formed by Pseudomonas aeruginosa PAO1 was inhibited by exposure to a combination of F-53B and Cr(VI).The combined pollution damaged the cell membranes and the structure of the biofilm,and inhibited the production of the Pseudomonas quinolone-based signal,which affected biofilm ***,the secretion of extracellular polymeric substances decreased as a result of this combined *** to F-53B and Cr(VI)individually or in combination could induce the excessive accumulation of intracellular reactive oxygen species(ROS),and the ROS positive rate of the bacteria increased under the treatment with 0.2 mmol/L of Cr(VI)and 250 nmol/L of F-53B,*** addition,the activities of superoxide dismutase(SOD)and catalase(CAT)were enhanced for scavenging ROS in the bacteria that were exposed to Cr(VI)and *** an antioxidant,rutin was used to repair the toxicity of Cr(VI)and F-53B towards the biofilm formed by the *** rutin was added to the bacteria medium,with either Cr(VI)or F-53B as pollutant,or with the combined pollutants,the extracellular protein content of the bacteria recovered to 0.84,0.94,and 0.85 times that of the control,***,the accumulation of ROS and the activities of SOD and CAT decreased,which indicated that the addition of rutin can alleviate the oxidative stress and promote the antioxidant stress system.

关键词： F-53B Chromium(Cr) Rutin Biofilm Toxic effect Repair

Comparison study of slag corrosion resistance of MgO–MgAl_(2)O_(4),MgO–CaO and MgO–C refractories under electromagnetic field

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Journal of Iron and Steel Research International 2021年第1期28卷 38-45页

作者： xin‑ming Ren Bei‑yue Ma Shi‑ming Li Hong‑xia Li Guo‑qi Liu Wen‑gang Yang Fan qian Shi‑xian Zhao Jing‑kun Yu Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) School of MetallurgyNortheastern UniversityShenyang 110819LiaoningChina State Key Laboratory of Advance Refractories Sinosteel Luoyang Institute of Refractories Research Co.Ltd.Luoyang 471039HenanChina

To illuminate the corrosion behavior of MgO-based refractories under electromagnetic field(EMF),herein,the slag corrosion and penetration resistance of MgO–MgAl_(2)O_(4),MgO–CaO,and MgO–C refractories were investigated using the rotary immersion slag resistance test at 1873 K for 1 *** results showed that the order of the good slag resistance of as-tested refractories was MgO–C>MgO–CaO>MgO–MgAl_(2)O_(4).The EMF accelerated the corrosion and penetration of slag to the refractories,which caused the molten slag to be easier into the refractories by natural convection and Marangoni *** addition,the MgO–C refractories did not show an overwhelming advantage in slag resistance because EMF impeded the formation of the dense protection ***,in view of the present results,the MgO–C refractories are still the most promising slag line material for refining furnace among MgO–MgAl_(2)O_(4),MgO–CaO,and MgO–C refractories.

关键词： MgO-based refractory Corrosion Basic slag Electromagnetic field

Influence of fiber posts on the fracture resistance of endodontically treated premolars with different dental defects

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International Journal of Oral Science 2013年第3期5卷 167-171页

作者： qian-qian Hou Yi-ming Gao Lei Sun School of Medicine Shanghai Jiao Tong University Department of Stomatology Ruijin Hospital School of Medicine Shanghai Jiao Tong University

This study aimed to evaluate the influence of quartz fiber post placement on the fracture resistance of endodontically treated premolars with different dental defects under dynamic *** extracted single-rooted mandibular premolars were randomized into five *** group was prepared according to numbers of residual walls ranged from 0 to *** each group was divided into two subgroups with one restored with quartz fiber posts and the other without *** no-post groups,gutta percha point 2 mm below cemento-enamel junction was *** resin was adapted to the well and used to shape the core *** tooth was restored with a complete metal *** loading was carried out in a masticatory simulator with a nominal load of 50 N at 2 Hz for 300 000 loading *** a quasi-statically load was applied in a universal testing machine 306 to the long axis with a crosshead speed of 1 mm？min21until *** were analyzed with one-way analysis of variance and pairwise comparison（P,0.05）.No specimens failed during dynamic *** fracture resistance enhanced with the increase of numbers of coronal walls and the differences were significant（P,0.05）.Placement of fiber posts had a significant effect when fewer than two walls remained（P,0.05）,but it had no significant influence in groups with two,three or four walls（P.0.05）.Fiber post did not change failure mode,and the fracture pattern was mainly *** dentin walls need to be retained in *** no less than two walls remained,a fiber post is not always necessary.

关键词： dynamic loading fiber post fracture resistance residual wall

Performance monitoring of non-gaussian chemical processes with modes-switching using globality-locality preserving projection

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Frontiers of Chemical Science and Engineering 2017年第3期11卷 429-439页

作者： xin Peng Yang Tang Wenli Du Feng qian Key Laboratory of Advanced Control and Optimization for Chemical Process Ministry of Education East China University of Science and Technology Shanghai 200237 China

In this paper, we propose a novel performance monitoring and fault detection method, which is based on modified structure analysis and globality and locality preserving （MSAGL） projection, for non-Gaussian processes with multiple operation conditions. By using locality preserving projection to analyze the embedding geometrical manifold and extracting the non-Gaussian features by independent component analysis, MSAGL preserves both the global and local structures of the data simultaneously. Furthermore, the tradeoff parameter of MSAGL is tuned adaptively in order to find the projection direction optimal for revealing the hidden structural information. The validity and effectiveness of this approach are illustrated by applying the proposed technique to the Tennessee Eastman process simulation under multiple operation conditions. The results demonstrate the advantages of the proposed method over conventional eigendecomposition-based monitoring methotis.

关键词： non-Gaussian processes subspace projection independent component analysis locality preserving projection finite mixture model

Experiments on and predictions about properties of sand bonded by microbe cement

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Science China(Technological Sciences) 2016年第8期59卷 1186-1193页

作者： qian ChunXiang RONG Hui YU XiaoNiu WANG xin School of Materials Science and Engineering Southeast University Nanjing 211189 China Research Institute of Green Construction Materials Southeast University Nanjing 211189 China

Microbe cement as a new bonding material is presented. Sandstone （0.05 m diameter, 0.5 m height） and sandpile （0.125 m^3） are joined by microbe cement to make a whole body. Evolutions in the related properties of treated sand samples are examined through compressive strength and calcite content. Results indicate that the structure of the cemented body is nonuniform, that the calcite content decreases with distance from the injection port, and that the compressive strength also decreases with dis- tance from the injection port. In addition, evolutions in the measured calcite content and compressive strength are summarized by a numerical model that considers microbe concentration distribution. The numerical results of the calcite content at different positions for 0.5 m height sandstone are similar to the test results, and the experimental results for calcite content and compres- sive strength of 0.125 m^3 cubic sandpile are similar to the numerical results. Prediction results indicate that the simulations should become a significant supplementary tool when microbe cement is applied in actual engineering projects.

关键词： microbe cement compressive strength calcite numerical model

Influence of dispersants on coal-water slurry prepared from the solid residue of plasma pyrolysis of coal

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Chinese Journal of Chemical Engineering 2020年第2期28卷 566-570页

作者： Chao qian Liang Zhao xin Ge xinzhi Chen School of Chemical and Biological Engineering Zhejiang UniversityHangzhou 310027China School of Chemical and Material Engineering Jiangnan UniversityWuxi 214122China

This work presents the influence of dispersants on coal-water slurry(CWS),which was prepared from the solid residue of plasma pyrolysis of *** effects of dispersant type,solid concentration,dispersant content,and temperature on the rheological properties of CWS are examined.A suitable empirical model regarding the relation between viscosity and temperature is *** the sedimentation experiment of CWS,dispersants are found to significantly promote the stability of CWS.

关键词： Plasma pyrolysis of coal Solid residue Dispersants CWS Rheology

Detection of Safety Helmet-Wearing Based on the YOLO_CA Model

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Computers, Materials & Continua 2023年第12期77卷 3349-3366页

作者： Xiaoqin Wu Songrong qian ming Yang State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China

Safety helmets can reduce head injuries from object impacts and lower the probability of safety accidents,as well as being of great significance to construction ***,for a variety of reasons,construction workers nowadays may not strictly enforce the rules of wearing safety *** order to strengthen the safety of construction site,the traditional practice is to manage it through methods such as regular inspections by safety officers,but the cost is high and the effect is *** the popularization and application of construction site video monitoring,manual video monitoring has been realized for management,but the monitors need to be on duty at all times,and thus are prone to ***,this study establishes a lightweight model YOLO_CA based on YOLOv5 for the automatic detection of construction workers’helmet wearing,which overcomes the shortcomings of the current manual monitoring methods that are inefficient and *** coordinate attention(CA)addition to the YOLOv5 backbone strengthens detection accuracy in complex scenes by extracting critical information and suppressing non-critical *** parameter compression with deeply separable convolution(DWConv).In addition,to improve the feature representation speed,we swap out C3 with a Ghost module,which decreases the floating-point operations needed for feature channel fusion,and CIOU_Loss was substituted with EIOU_Loss to enhance the algorithm’s localization ***,the original model needs to be improved so as to enhance the detection of safety *** experimental results show that the YOLO_CA model achieves good results in all indicators compared with the mainstream *** with the original model,the mAP value of the optimized model increased by 1.13%,GFLOPs cut down by 17.5%,and there is a 6.84%decrease in the total model parameters,furthermore,the weight size cuts down by 4.26%,FPS increased by 39.58%,and the detection effect and model size of

关键词： Safety helmet CA YOLOv5 ghost module

A QoS Guarantee Service Serving Model in LEO Satellite Networks Based on Differential Game

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China Communications 2014年第A2期11卷 128-134页

作者： LIU qian ZHAO ming LIN Fuhong School of Computer and Communication Engineering University of Science and Technology Beijing Beijing 100083 P. R. China Hotan Teachers College Hetian 848000 Xinjiang P. R. China

Low Earth Orbit （LEO） satellites networks can provide multimedia service and plays an increasingly important role in the exploitation of space. However, one of the challenges in LEO satellites networks is that the services are suffered from high symbol error, limited storage space and limited available energy. To analyze the performance of the service in LEO satellites networks, a model, based on differential game, is proposed for satisfying the QoS requirements of multimedia applications. The controller of our model is the transmitting rate and the object is to maximize the payoff depending on the error symbol rate, the available energy, the bandwidth and the process ability so as to guarantee the QoS service. In order to solve our built model, we use the Bellman theorem to make formulas on the trance of the optimal transmitting rate. Furthermore, simulation results verify that the service can be maximized by using our derived transmitting rate trance.

关键词： LEO satellite networks QoS differential game