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Altered Expression of Nicotinic Receptors in Perinatal Life Related to Prenatal Exposure to Toxics—An Overview of the Research Carried Out on This Topic at the “Lino Rossi” Research Center of the Milan University
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作者 Anna Maria Lavezzi 《Journal of Behavioral and Brain Science》 2020年第10期420-431,共12页
The article aims to underline the impact of nicotine and pesticides on neuronal <i>α</i>7-nicotinic acetylcholine receptors expression in brainstem regions receiving cholinergic projections, given their f... The article aims to underline the impact of nicotine and pesticides on neuronal <i>α</i>7-nicotinic acetylcholine receptors expression in brainstem regions receiving cholinergic projections, given their fundamental role during the neuronal development. The in-depth histopathological/immunohistochemical examination of the autonomic nervous system performed at the “Lino Rossi” Research Center of the Milan University on a wide group of sudden unexpected fetal and infant deaths, highlighted the frequent hypodevelopment of brainstem structures checking the vital functions associated to altered expression of <i>α</i>7-nicotinic acetylcholine receptors and smoke absorption in pregnancy. A dysregulation of the catecholamine system was also observed in the cerebellar cortex of the same cases. However, in a not negligible percentage of sudden deaths with altered expression of <i>α</i>7-nicotinic receptors, the mothers never smoked but lived in rural areas. Specific analytical procedures showed the presence of agricultural pesticides in cerebral cortex samples of these victims. Therefore, it is possible to believe that the exposition to pesticides during pregnancy can produce the same harmful effects as nicotine on the nicotinic acetylcholine receptors. Moreover, alterations of <i>α</i>7-nicotinic acetylcholine receptors receptor expression were also detected in the lungs of many sudden perinatal death victims, allowing to consider even these findings as possible consequence of maternal exposure to toxic factors. 展开更多
关键词 Nicotine Pesticides Endocrine Disruptor Compounds (EDCs) α7-Nicotinic Acetylcholine Receptors NEUROPATHOLOGY Sudden Infant Death Syndrome (SIDS) Sudden Intrauterine Unexplained Death (SIUDS)
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Evaluation of excavation damaged zones(EDZs)in Horonobe Underground Research Laboratory(URL)
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作者 Koji Hata Sumio Niunoya +1 位作者 Kazuhei Aoyagi Nobukatsu Miyara 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期365-378,共14页
Excavation of underground caverns,such as mountain tunnels and energy-storage caverns,may cause the damages to the surrounding rock as a result of the stress redistribution.In this influenced zone,new cracks and disco... Excavation of underground caverns,such as mountain tunnels and energy-storage caverns,may cause the damages to the surrounding rock as a result of the stress redistribution.In this influenced zone,new cracks and discontinuities are created or propagate in the rock mass.Therefore,it is effective to measure and evaluate the acoustic emission(AE)events generated by the rocks,which is a small elastic vibration,and permeability change.The authors have developed a long-term measurement device that incorporates an optical AE(O-AE)sensor,an optical pore pressure sensor,and an optical temperature sensor in a single multi-optical measurement probe(MOP).Japan Atomic Energy Agency has been conducting R&D activities to enhance the reliability of high-level radioactive waste(HLW)deep geological disposal technology.In a high-level radioactive disposal project,one of the challenges is the development of methods for long-term monitoring of rock mass behavior.Therefore,in January 2014,the long-term measurements of the hydro-mechanical behavior of the rock mass were launched using the developed MOP in the vicinity of 350 m below the surface at the Horonobe Underground Research Center.The measurement results show that AEs occur frequently up to 1.5 m from the wall during excavation.In addition,hydraulic conductivity increased by 2e4 orders of magnitude.Elastoplastic analysis revealed that the hydraulic behavior of the rock mass affected the pore pressure fluctuations and caused micro-fractures.Based on this,a conceptual model is developed to represent the excavation damaged zone(EDZ),which contributes to the safe geological disposal of radioactive waste. 展开更多
关键词 Excavation damaged zone(EDZ) Optical sensor Long-term monitoring Acoustic emission(AE) Shaft sinking
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Synthesis of Organic-Inorganic Hybrid Aluminum Hypophosphite Microspheres Flame Retardant and Its Flame Retardant Research on Thermoplastic Polyurethane
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作者 刘生鹏 XU Zhi +5 位作者 ZHANG Xinyuan WEI Huan XIONG Yun DING Yigang HUANG Wenbo 许莉莉 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期221-233,共13页
Aluminum hypophosphite microspheres(AHP) were synthesized by hydrothermal method using NaH2PO2·H2O and AlCl3·6H2O as raw materials, and then the AHP microspheres were polymerized by surface polymerization of... Aluminum hypophosphite microspheres(AHP) were synthesized by hydrothermal method using NaH2PO2·H2O and AlCl3·6H2O as raw materials, and then the AHP microspheres were polymerized by surface polymerization of micro-nanospheres with cyclic cross-linked poly(cyclotriphosphazene-co-4,4'-sulfonyldiphenol)(PZS). A new organic-inorganic poly(phosphonitrile)-modified aluminum hypophosphite microspheres(PZS-AHP) were synthesized by encapsulation and applied to flame retardant thermoplastic polyurethane(TPU). The microstructure and chemical composition of the PZS-AHP microsphere were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray spectroscopy. The thermal stability of PZS-AHP microsphere was explored with thermogravimetric analysis. Thermogravimetric data indicate that the PZS-AHP microspheres have excellent thermal stability. The thermal and flame-retarding properties of the TPU composites were evaluated by thermogravimetric(TG), limited oxygen index tests(LOI), and cone calorimeter test(CCT). The TPU composite achieved vertical burning(UL-94) V-0 grade and LOI value reached 29.2% when 10 wt% PZS-AHP was incorporated. Compared with those of pure TPU, the peak heat release rate(pHRR) and total heat release(THR) of TPU/10%PZS-AHP decreased by 82.2% and 42.5%, respectively. The results of CCT indicated that PZS-AHP microsphere could improve the flame retardancy of TPU composites. 展开更多
关键词 POLYPHOSPHAZENE thermoplastic polyurethane flame retardancy aluminum hypophosphite surface polymerization
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Research progress on classification,source,application of phytosterol esters,and their thermal oxidation stability
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作者 Dami Li Shangde Sun Jingnan Chen 《Grain & Oil Science and Technology》 CAS 2024年第1期1-11,共11页
Phytosterol esters can effectively decrease serum cholesterol concentration in the human body and prevent cardio-cerebrovascular diseases.It was found that phytosterol esters exhibited better solubility and bioavailab... Phytosterol esters can effectively decrease serum cholesterol concentration in the human body and prevent cardio-cerebrovascular diseases.It was found that phytosterol esters exhibited better solubility and bioavailability than free phytosterols.In recent years,phytosterol esters have attracted increasing attention.However,during food processing,phytosterol esters are susceptible to degradation at high temperatures,resulting in certain losses and formation of potentially harmful substances for humans.This paper reviews the relevant literatures and updates on the thermal oxidation stability of phytosterol esters in recent years from the following aspects:(i)Sources,physiological activities,and applications of phytosterol esters;(ii)Oxidation mechanism of phytosterol esters;(iii)Effects of phytosterols species,the volume of addition,food matrix,heating temperature and time,and antioxidants on the thermal loss and oxidation stability of phytosterol esters.The research progress on the safety of phytosterol esters is also discussed in detail.Additionally,the prospects for future research are highlighted. 展开更多
关键词 Thermal stability Loss rate Oxidation mechanism Phytosterol esters
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Research Progress on Effects of Continuous Cropping on Soil Microbial Florae and Its Restoration
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作者 Zaixiang ZHU Zebin CHEN +5 位作者 Shengguang XU Zhiwei FAN Li LIN Tianfang WANG Qingmei LI Yue YAN 《Agricultural Biotechnology》 2024年第2期75-80,共6页
Continuous cropping has become a common form of agricultural production at present, but with the increase of continuous cropping years, continuous cropping obstacles such as soil-borne diseases and plant growth potent... Continuous cropping has become a common form of agricultural production at present, but with the increase of continuous cropping years, continuous cropping obstacles such as soil-borne diseases and plant growth potential decline are becoming more and more common. At present, the causes of continuous cropping obstacles and continuous cropping restoration have become a hot issue in agricultural research. This paper summarized the effects of continuous cropping obstacles on soil microbial community structure and main technical methods to repair continuous cropping obstacles, such as agricultural measure management, microbial balance adjustment and soil improvement, aiming to provide theoretical reference for protecting the sustainable utilization of soil ecosystem and ensuring the stability of crop production. 展开更多
关键词 Continuous cropping obstacle Rhizosphere soil MICROORGANISM Soil remediation Soil improvement
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Current status of early gastric cancer screening research
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作者 Can Hu Li Yuan Xiangdong Cheng 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第3期218-222,共5页
Gastric cancer is a predominant threat to the health and well-being of China's residents. Data from the World Health Organization(WHO) in 2020 revealed that gastric cancer in China notably accounted for 44.0% of n... Gastric cancer is a predominant threat to the health and well-being of China's residents. Data from the World Health Organization(WHO) in 2020 revealed that gastric cancer in China notably accounted for 44.0% of new cases worldwide and 48.6% of global deaths attributed to this malignancy~1. 展开更多
关键词 CANCER GASTRIC GASTRIC
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Research progress of alkaline earth metal iron-based oxides as anodes for lithium-ion batteries
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作者 Mingyuan Ye Xiaorui Hao +6 位作者 Jinfeng Zeng Lin Li Pengfei Wang Chenglin Zhang Li Liu Fanian Shi Yuhan Wu 《Journal of Semiconductors》 EI CAS CSCD 2024年第2期21-33,共13页
Anode materials are an essential part of lithium-ion batteries(LIBs),which determine the performance and safety of LIBs.Currently,graphite,as the anode material of commercial LIBs,is limited by its low theoretical cap... Anode materials are an essential part of lithium-ion batteries(LIBs),which determine the performance and safety of LIBs.Currently,graphite,as the anode material of commercial LIBs,is limited by its low theoretical capacity of 372 mA·h·g^(−1),thus hindering further development toward high-capacity and large-scale applications.Alkaline earth metal iron-based oxides are considered a promising candidate to replace graphite because of their low preparation cost,good thermal stability,superior stability,and high electrochemical performance.Nonetheless,many issues and challenges remain to be addressed.Herein,we systematically summarize the research progress of alkaline earth metal iron-based oxides as LIB anodes.Meanwhile,the material and structural properties,synthesis methods,electrochemical reaction mechanisms,and improvement strategies are introduced.Finally,existing challenges and future research directions are discussed to accelerate their practical application in commercial LIBs. 展开更多
关键词 alkali-earth metal iron-based oxides anodes lithium-ion batteries electrochemical energy storage
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Research on Preparation and Electrochemical Performance of the High Compacted Density Ni-Co-Mn Ternary Cathode Materials
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作者 Fupeng Zhi Juanhui Wang +1 位作者 Xiaomin Zhang Jun Zhang 《Advances in Materials Physics and Chemistry》 CAS 2024年第3期47-53,共7页
The high compacted density LiNi<sub>0.5-x</sub>Co<sub>0.2</sub>Mn<sub>0.3</sub>Mg<sub>x</sub>O<sub>2</sub> cathode material for lithium-ion batteries was syn... The high compacted density LiNi<sub>0.5-x</sub>Co<sub>0.2</sub>Mn<sub>0.3</sub>Mg<sub>x</sub>O<sub>2</sub> cathode material for lithium-ion batteries was synthesized by high temperature solid-state method, taking the Mg element as a doping element and the spherical Ni<sub>0.5</sub>Co<sub>0.2</sub>Mn<sub>0.3</sub> (OH)<sub>2</sub>, Li<sub>2</sub>CO<sub>3</sub> as raw materials. The effects of calcination temperature on the structure and properties of the products were investigated. The structure and morphology of cathode materials powder were analyzed by X-ray diffraction spectroscopy (XRD) and scanning electronmicroscopy (SEM). The electrochemical properties of the cathode materials were studied by charge-discharge test and cyclic properties test. The results show that LiNi<sub>0.4985</sub>Co<sub>0.2</sub>Mn<sub>0.3</sub> Mg<sub>0.0015</sub>O<sub>2</sub> cathode material prepared at calcination temperature 930°C has a good layered structure, and the compacted density of the electrode sheet is above 3.68 g/cm<sup>3</sup>. The discharge capacity retention rate is more than 97.5% after 100 cycles at a charge-discharge rate of 1C, displaying a good cyclic performance. 展开更多
关键词 High Compacted Density Ternary Cathode Materials Electrochemical Performance
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A novel predictor of unsustained return of spontaneous circulation in cardiac arrest patients through a combination of capnography and pulse oximetry: a multicenter observational study
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作者 Jing Yang Hanqi Tang +11 位作者 Shihuan Shao Feng Xu Yangyang Fu Shengyong Xu Chen Li Yan Li Yang Liu Joseph Harold Walline Huadong Zhu Yuguo Chen Xuezhong Yu Jun Xu 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第1期16-22,共7页
BACKGROUND:Unsustained return of spontaneous circulation(ROSC)is a critical barrier to survival in cardiac arrest patients.This study examined whether end-tidal carbon dioxide(ETCO_(2))and pulse oximetry photoplethysm... BACKGROUND:Unsustained return of spontaneous circulation(ROSC)is a critical barrier to survival in cardiac arrest patients.This study examined whether end-tidal carbon dioxide(ETCO_(2))and pulse oximetry photoplethysmogram(POP)parameters can be used to identify unsustained ROSC.METHODS:We conducted a multicenter observational prospective cohort study of consecutive patients with cardiac arrest from 2013 to 2014.Patients’general information,ETCO_(2),and POP parameters were collected and statistically analyzed.RESULTS:The included 105 ROSC episodes(from 80 cardiac arrest patients)comprised 51 sustained ROSC episodes and 54 unsustained ROSC episodes.The 24-hour survival rate was significantly higher in the sustained ROSC group than in the unsustained ROSC group(29.2%vs.9.4%,P<0.05).The logistic regression analysis showed that the difference between after and before ROSC in ETCO_(2)(ΔETCO_(2))and the difference between after and before ROCS in area under the curve of POP(ΔAUCp)were independently associated with sustained ROSC(odds ratio[OR]=0.931,95%confi dence interval[95%CI]0.881-0.984,P=0.011 and OR=0.998,95%CI 0.997-0.999,P<0.001).The area under the receiver operating characteristic curve ofΔETCO_(2),ΔAUCp,and the combination of both to predict unsustained ROSC were 0.752(95%CI 0.660-0.844),0.883(95%CI 0.818-0.948),and 0.902(95%CI 0.842-0.962),respectively.CONCLUSION:Patients with unsustained ROSC have a poor prognosis.The combination ofΔETCO_(2) andΔAUCp showed signifi cant predictive value for unsustained ROSC. 展开更多
关键词 Return of spontaneous circulation Pulse oximetry photoplethysmogram End-tidal carbon dioxide Cardiac arrest Cardiopulmonary resuscitation
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Impact of microplastics and nanoplastics on liver health:Current understanding and future research directions
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作者 Chun-Cheng Chiang Hsuan Yeh +2 位作者 Ruei-Feng Shiu Wei-Chun Chin Tzung-Hai Yen 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1011-1017,共7页
With continuous population and economic growth in the 21st century,plastic pollution is a major global issue.However,the health concern of microplastics/nanoplastics(MPs/NPs)decomposed from plastic wastes has drawn pu... With continuous population and economic growth in the 21st century,plastic pollution is a major global issue.However,the health concern of microplastics/nanoplastics(MPs/NPs)decomposed from plastic wastes has drawn public attention only in the recent decade.This article summarizes recent works dedicated to understanding the impact of MPs/NPs on the liver-the largest digestive organ,which is one of the primary routes that MPs/NPs enter human bodies.The interrelated mechanisms including oxidative stress,hepatocyte energy re-distribution,cell death and autophagy,as well as immune responses and inflammation,were also featured.In addition,the disturbance of microbiome and gut-liver axis,and the association with clinical diseases such as metabolic dysfunction-associated fatty liver disease,steatohepatitis,liver fibrosis,and cirrhosis were briefly discussed.Finally,we discussed potential directions in regard to this trending topic,highlighted current challenges in research,and proposed possible solutions. 展开更多
关键词 Microplastics Nanoplastics LIVER Reactive oxidative species Cell death Autophagy Innate immunity Metabolic dysfunction-associated fatty liver disease Gut-liver axis
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A Book Review of Becoming a Reading Teacher:Connecting Research and Practice
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作者 Peipei Xu Lin Yu 《Journal of Contemporary Educational Research》 2024年第3期232-236,共5页
The book Becoming a Reading Teacher:Connecting Research and Practice aims to encourage readers to regard reading as a lifelong habit.To bridge the gap between teachers and researchers,this book is structured around fo... The book Becoming a Reading Teacher:Connecting Research and Practice aims to encourage readers to regard reading as a lifelong habit.To bridge the gap between teachers and researchers,this book is structured around four parts:reading as a linguistic process,reading as a personal experience,reading as a collective experience,and reading as a classroom practice.The definition of a reading teacher can be interpreted in two ways:the teacher who builds readings into the lesson and the teacher who provides the opportunity for learners to be readers,but who is a reader themselves.Such teachers regard reading as a lifelong learning habit and pass on the enthusiasm to learners,eventually creating a reading culture beyond the classroom.However,the necessity for reading teachers to participate in the research may be explained as follows.Firstly,new research may change one’s mind.What’s more,research allows teachers to turn their difficulties,surprises,and challenges into questions,and to seek answers to those questions.In addition,research helps teachers overcome the challenges in teaching by discovering new strategies.Research can also help to prove teachers’choices and decisions in teaching.Secondly,research allows teachers to see the role they play in the bigger picture.Research connects teachers with others and gives them a broader and shared perspective on their questions and experiences.Last but not least,research informs and promotes changes in policy,thinking,and so on. 展开更多
关键词 Research PRACTICES READING Lifelong habit
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Trends and hotspots of global ultra-processed food research(2010-2023):A scientometric study
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作者 Zi-Yi Wang Cun-Cun Lu +6 位作者 Wen-Di Liu Lu Cui Xiu-Xiu Deng Zhi-Jiang Bi Fen-Fen E Ke-Hu Yang Xiu-Xia Li 《Food and Health》 2024年第1期1-15,共15页
Background:Recently,ultra-processed foods(UPFs)have attracted considerable attention,leading to numerous studies worldwide.Scientometrics is currently gaining popularity among scientific communities,offering advantage... Background:Recently,ultra-processed foods(UPFs)have attracted considerable attention,leading to numerous studies worldwide.Scientometrics is currently gaining popularity among scientific communities,offering advantage of providing critical references to scholars of specific fields.Methods:This scientometric study aimed to analyze trends and hotspots of UPF research using English articles or reviews related to UPFs retrieved from the Web of Science Core Collection on March 5,2023.Two independent researchers selected the identified records on titles,abstracts,and author’s keywords,and the data were analyzed using R-bibliometrix,CiteSpace,and VOSviewer.Results:A total of 1018 publications(901 articles and 117 reviews)published from 2010 to 2023 were included.The result showed a significant increase in UPF publications over the past decades.Brazil published the highest number of papers(n=473),with over half of the top 10 active institutions were located in Brazil.The University of São Paulo contributed the most publications(n=206)and the 10 most productive authors belonged to this institution,with Monteiro CA and Levy RB contributing the most publications.The main research foundations included the NOVA system,the definition of UPFs,the prevalence of UPFs,and the impact of UPFs on dietary quality and health status.The main research frontiers included topics such as“systematic review,”“NOVA food classification,”“COVID-19,”“diabetes,”“pregnancy,”“food addiction,”“warning labels,”“plant-based diet,”and“commercial determinants of health”.Conclusions:This study provided a comprehensive overview of development trends and research hotspots of global UPF studies. 展开更多
关键词 SCIENTOMETRICS ultra-processed foods VOSviewer CiteSpace HEALTH
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Research on the feasibility of storage and estimation model of storage capacity of CO_(2)in fissures of coal mine old goaf 被引量:1
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作者 Yang Ding Shugang Li +4 位作者 Bing Zhu Haifei Lin Jingfei Zhang Junhong Tan Wenbin Chen 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第6期675-686,共12页
The concept of the carbon cycle in the old goaf of a coal mine based on CO_(2)utilization and storage was put forward adhering to the principle of low-carbon development,utilization of space resources in old goafs,and... The concept of the carbon cycle in the old goaf of a coal mine based on CO_(2)utilization and storage was put forward adhering to the principle of low-carbon development,utilization of space resources in old goafs,and associated gas resources development.Firstly,the evolution characteristics of overburden fissures in the goaf of the case was studied using a two-dimensional physical similarity simulation test,the sealing performance of the caprocks after stabilization was analyzed,and the fissures were counted and classi-fied.Then,the process of gaseous CO_(2)injection in the connected fissure was simulated by Ansys Fluent software,and the migration law and distribution characteristics of CO_(2)under the condition of gaseous CO_(2)injection were analyzed.Finally,the estimation models of free CO_(2)storage capacity in the old goaf were constructed considering the proportion of connected fissure and the effectiveness of CO_(2)injection.The CO_(2)storage capacity in the old goaf of the case coal mine was estimated.The results showed that a caprock group of“hard-thickness low-permeability hard-thickness”was formed after the caprock-fissures system in the goaf of the case tended to be stable vertically.The connected fissure,occlude cracks,and micro-fractures in the goaf accounted for 85.5%,8.5%,and 6%of the total fissures,respectively.Gaseous CO_(2)first migrated to the bottom of the connected fissure after CO_(2)was injected into the goaf,then spread horizontally along the bottom of the connected fissure after reaching the bottom,and finally spread longitudinally after filling the bottom of the entire connected fissure.The theoretical and effective storage capacities of free CO_(2)at normal temperature and pressure in the old goaf of the case were 9757 and 7477 t,respectively.The effective storage capacity of free CO_(2)at normal temperature and pressure in the old goaf after all minefield mined was 193404 t.The research can provide some reference for the coal mining industry to help the goal of“carbon peaking and carbon neutrality”. 展开更多
关键词 Carbon cycle Old goaf FISSURE CO_(2)storage FEASIBILITY Storage capacity
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The Progress of IGS Analysis Center at Wuhan University 被引量:1
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作者 Weiping JIANG Qile ZHAO +7 位作者 Min LI Jing GUO Jianghui GENG Zhao LI Shengfeng GU Qiang ZHANG Zhigang HU Na WEI 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第3期46-57,共12页
As one of the Analysis Centers(AC)of the International GNSS Service(IGS),Wuhan University(WHU)has been contributing to the IGS by providing ultra-rapid as well as rapid orbit and clock solutions for the established GP... As one of the Analysis Centers(AC)of the International GNSS Service(IGS),Wuhan University(WHU)has been contributing to the IGS by providing ultra-rapid as well as rapid orbit and clock solutions for the established GPS and GLONASS since 2012.In the same year,the IGS initiated the Multi-GNSS Experiment(MGEX)to support the analysis of the emerging GNSS systems and prepare the IGS for Multi-GNSS,which includes GPS,GLONASS,the European Galileo system,the Chinese Beidou Navigation Satellite System(BDS),the Japanese Quasi-Zenith Satellite System(QZSS)and the Indian Regional Navigation Satellite System(IRNSS/NaVIC).The major products,i.e.,orbits,Earth Orientation Parameters(EOPs),satellite clock as well as attitude have also been provided by WHU since 2012.More recently,WHU has engaged the third reprocessing of IGS for generating the highly accurate station coordinates as inputs for establishment of the International Terrestrial Reference Frame(ITRF)2020 during 2019—2020.This article presents the recent major advancements of the IGS AC at Wuhan University,including precise products,real-time products,bias products,antenna phase center calibration,and the non-linear motion modeling for GNSS Reference Stations. 展开更多
关键词 GNSS BDS International GNSS Service orbit and clock products non-linear motion
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Additive manufacturing of magnesium matrix composites: Comprehensive review of recent progress and research perspectives 被引量:2
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作者 Chenghang Zhang Zhuo Li +2 位作者 Jikui Zhang Haibo Tang Huaming Wang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第2期425-461,共37页
The magnesium matrix composites(MMCs) formed by introducing reinforcements to magnesium alloys overcome the limitations of the mechanical properties to a certain extent, presenting unique and excellent properties that... The magnesium matrix composites(MMCs) formed by introducing reinforcements to magnesium alloys overcome the limitations of the mechanical properties to a certain extent, presenting unique and excellent properties that any component does not have, such as high specific stiffness and specific strength, good dimensional stability, outstanding shock absorption performance, excellent electromagnetic shielding and hydrogen storage characteristics, etc. As an emerging manufacturing technology, additive manufacturing(AM) is based on the design of threedimensional(3D) data model to obtain 3D objects through layer-by-layer processing, which possesses the advantages of short manufacturing cycle, high material utilization rate, high degree of design freedom, excellent mechanical properties and the ability to fabricate complex structural components. Combining the high stiffness and high strength properties of MMCs and the technical advantages of AM forming complex structural parts with high performance, the prepared AM MMCs have huge potential advantages and broad application prospects in new high-tech industries such as automobile, aerospace, consumer electronics and biomedicine, etc. This paper reviews the research progress in the field of AM MMCs, mainly introduces the main AM technologies, including selective laser melting(SLM), electron beam selective melting(EBSM), laser engineered net shaping(LENS) and wire and arc additive manufacturing(WAAM). The formation mechanism and control methods of the typical defects including balling effect, porosity, poor fusion, loss of alloy elements and cracks produced during AM are discussed. The main challenges of AM MMCs are proposed from the aspects of composition design and the preparation of powder raw material. The relationship between the microstructure and mechanical properties, corrosion performance and biocompatibility of AM MMCs are elaborated in detail. The application potential of AM MMCs in various fields at present and in the future is introduced. Finally, the development direction and urgent problems to be solved in the AM MMCs are prospected. 展开更多
关键词 Magnesium matrix composites Additive manufacturing DEFECTS MICROSTRUCTURE PROPERTIES
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Open-Source Codes of Topology Optimization: A Summary for Beginners to Start Their Research 被引量:1
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作者 Yingjun Wang Xinqing Li +1 位作者 Kai Long Peng Wei 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期1-34,共34页
Topology optimization(TO),a numerical technique to find the optimalmaterial layoutwith a given design domain,has attracted interest from researchers in the field of structural optimization in recent years.For beginner... Topology optimization(TO),a numerical technique to find the optimalmaterial layoutwith a given design domain,has attracted interest from researchers in the field of structural optimization in recent years.For beginners,opensource codes are undoubtedly the best alternative to learning TO,which can elaborate the implementation of a method in detail and easily engage more people to employ and extend the method.In this paper,we present a summary of various open-source codes and related literature on TO methods,including solid isotropic material with penalization(SIMP),evolutionary method,level set method(LSM),moving morphable components/voids(MMC/MMV)methods,multiscale topology optimization method,etc.Simultaneously,we classify the codes into five levels,fromeasy to difficult,depending on their difficulty,so that beginners can get started and understand the form of code implementation more quickly. 展开更多
关键词 Topology optimization open-source code optimization methods code classification BEGINNERS
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Experimental research and energy analysis of a new type of dry ice powder pneumatic rock breaking technology 被引量:2
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作者 Xiaofei Wang Shaobin Hu +2 位作者 Enyuan Wang Qiang Zhang Bing Liu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第4期423-435,共13页
When the traditional drill and blast method is applied to rock crushing projects,it has strong vibration,loud noise and dust pollution,so it cannot be used in densely populated areas such as urban public works.We deve... When the traditional drill and blast method is applied to rock crushing projects,it has strong vibration,loud noise and dust pollution,so it cannot be used in densely populated areas such as urban public works.We developed a supercritical CO_(2)true triaxial pneumatic rock-breaking experimental system,and conducted laboratory and field tests of dry ice powder pneumatic rock-breaking.The characteristics of the blast-induced vibration velocity waveform and the evolution of the vibration velocity and frequency with the focal distance were analyzed and discussed.The fracturing mechanism of dry ice powder pneumatic rock breaking is studied.The research results show that:(1)The vibration velocity induced by dry ice powder pneumatic rock breaking decays as a power function with the increase of the focal distance;(2)The vibration frequency caused by dry ice powder pneumatic rock breaking is mainly distributed in 1–120 Hz.Due to the dispersion effect,the dominant frequency of 10–30 Hz appears abnormally attenuated;(3)The traditional CO_(2)phase change fracturing energy calculation formula is also applicable to dry ice pneumatic rock breaking technology,and the trinitrotoluene(TNT)equivalent of fracturing energy is applicable to the Sadovsky formula;(4)Dry ice powder pneumatic rock breaking is shock wave and highenergy gas acting together to fracture rock,which can be divided into three stages,among which the gas wedge action of high-energy gas plays a dominant role in rock mass damage. 展开更多
关键词 Dry ice powder pneumatic rock breaking Cracking mechanism Energy analysis Vibration frequency
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Safety of butylphthalide and edaravone in patients with ischemic stroke:a multicenter real-world study 被引量:1
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作者 Shu-Xian LYU Dong-Fang QIAN +13 位作者 Yu-Fei FENG Cheng-Wu SHEN Lu-Bo GUO Jian-Tao LYU Peng-Fei JIN Ting LI Si-Yuan TAN Zi-Xuan ZHANG Lin HUANG Xue ZHONG Le-Qun SU Xin HU Xin HUANG Xue-Yan CUI 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2023年第4期293-308,共16页
BACKGROUND Butylphthalide(NBP)and edaravone(EDV)injection are common acute ischemic stroke medications in China,but there is a lack of large real-world safety studies on them.This study aimed to determine the incidenc... BACKGROUND Butylphthalide(NBP)and edaravone(EDV)injection are common acute ischemic stroke medications in China,but there is a lack of large real-world safety studies on them.This study aimed to determine the incidence of adverse events,detect relevant safety signals,and assess the risk factors associated with these medications in real-world populations.METHODS In this study,data of acute ischemic stroke patients were extracted from the electronic medical record database of six tertiary hospitals between January 2019 and August 2021.Baseline confounders were eliminated using propensity score matching.The drugs’safety was estimated by comparing the results of 24 laboratory tests standards on liver function,kidney function,lipid level,and coagulation function.The drugs’relative risk was estimated by logistic regression.A third group with patients who did not receive NBP or EDV was constructed as a reference.Prescription sequence symmetry analysis was used to evaluate the associations between adverse events and NBP and EDV,respectively.RESULTS 81,292 patients were included in this study.After propensity score matching,the NBP,EDV,and third groups with 727patients in each group.Among the 15 test items,the incidence of adverse events was lower in the NBP group than in the EDV group,and the differences were statistically significant.The multivariate logistic regression equation revealed that NBP injection was not a promoting factor for abnormal laboratory test results,whereas EDV had statistically significant effects on aspartate transaminase,low-density lipoprotein cholesterol and total cholesterol.Prescription sequence symmetry analysis showed that NBP had a weak correlation with abnormal platelet count.EDV had a positive signal associated with abnormal results in gamma-glutamyl transferase,alanine aminotransferase,aspartate aminotransferase,prothrombin time,and platelet count.CONCLUSIONS In a large real-world population,NBP has a lower incidence of adverse events and a better safety profile than EDV or other usual medications. 展开更多
关键词 PATIENTS DRUGS injection
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Research status and prospect of separators for magnesium-sulfur batteries
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作者 Shaopeng Chen Yaru Wang +6 位作者 Yukun Sun Duo Zhang Shuxin Zhang Yazhen Zhao Jiulin Wang Jun Yang Yanna NuLi 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期225-246,I0007,共23页
Magnesium-sulfur(Mg-S)batteries have attracted wide research attention in recent years,and are considered as one of the major candidates to replace lithium-ion batteries due to the high theoretical energy density,low ... Magnesium-sulfur(Mg-S)batteries have attracted wide research attention in recent years,and are considered as one of the major candidates to replace lithium-ion batteries due to the high theoretical energy density,low costs of active materials,and high safety.However,there are still significant challenges that need to be overcome before they can reach the large-scale practical applications.The key issue is the dissolution and shuttle effect of magnesium polysulfides(Mg-PSs),which leads to severe capacity degradation and shortens cycling life,greatly limiting the development of Mg-S batteries.In order to overcome these challenges,great efforts have been made in cathode materials,electrolytes,and separators.Herein,we review the investigations on suppressing the shuttle effect of Mg-PSs via the modification of separators,including schemes such as coating the functional materials that can hold Mg-PSs on the surface of polyolefin-based or glass fiber(GF)separators,forming gel polymer separators via cross-linking polymerization reactions,and developing gel polymer electrolytes coupled with GF separators.Furthermore,an outlook is proposed for the future design on separator exploitation to accelerate the development of Mg-S battery technology. 展开更多
关键词 Magnesium-sulfur batteries POLYSULFIDES Shuttle effect Separator modification Gel polymer electrolytes
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Drilling-based measuring method for the c-φ parameter of rock and its field application 被引量:1
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作者 Bei Jiang Fenglin Ma +5 位作者 Qi Wang Hongke Gao Dahu Zhai Yusong Deng Chuanjie Xu Liangdi Yao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第1期65-76,共12页
The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(R... The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(RCZ) is built. The formula for an ultimate cutting force is established based on the limit equilibrium principle. The relationship between digital drilling parameters(DDP) and the c-φ parameter(DDP-cφ formula, where c refers to the cohesion and φ refers to the internal friction angle) is derived, and the response of drilling parameters and cutting ratio to the strength parameters is analyzed. The drillingbased measuring method for the c-φ parameter of rock is constructed. The laboratory verification test is then completed, and the difference in results between the drilling test and the compression test is less than 6%. On this basis, in-situ rock drilling tests in a traffic tunnel and a coal mine roadway are carried out, and the strength parameters of the surrounding rock are effectively tested. The average difference ratio of the results is less than 11%, which verifies the effectiveness of the proposed method for obtaining the strength parameters based on digital drilling. This study provides methodological support for field testing of rock strength parameters. 展开更多
关键词 Digital drilling Rock crushing zone c-u parameter Measurement method Field application
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