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Zircon U-Pb dating of metagabbro masses from the Liwu Group Complex within the Taka dome:Geochronological constraints on the Indosinian-Yanshanian tectonic events in western Sichuan,China
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作者 Hong-chao Zhang Hong-bing Zhou +7 位作者 Bo Yan Chong-bo Sun Yue-zhong Wang Yun-chuan Zhao Yao Wen Ren-liang Cao Yang Qin Hong-qi Tan 《China Geology》 2025年第4期865-868,I0004-I0006,共7页
1.Objective The Songpan-Ganze terrane is a key region for understanding the tectonic evolution of the Tibetan Plateau and the Yangtze Craton.The Songpan-Ganzi complex comprises a thick succession of deformed Ladinian-... 1.Objective The Songpan-Ganze terrane is a key region for understanding the tectonic evolution of the Tibetan Plateau and the Yangtze Craton.The Songpan-Ganzi complex comprises a thick succession of deformed Ladinian-Norian turbidites(ca.230-203 Ma),covering about 200000 km^(2)of the eastern Tibet Plateau with a volume of approximately 2.0×10^(6)km^(3)(Fig.1a).Furthermore,this complex has over 100 Permian-Cenozoic felsic plutons. 展开更多
关键词 u pb dating INDOSINIAN zircon METAGABBRO taka dome YANSHANIAN liwu group complex tectonic events
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Surrounding rock deformation characteristics and control strategies during passing through abandoned roadway group
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作者 YANG Feng SUN Qiang +2 位作者 ZHOU Nan CHEN Yong WEI Yongqi 《Journal of Mountain Science》 2025年第7期2707-2722,共16页
The disorderly mining activities and irrational layout in underground coal mines have left a large number of adjacent abandoned roadways.During the process of a working face passing through abandoned roadways,these st... The disorderly mining activities and irrational layout in underground coal mines have left a large number of adjacent abandoned roadways.During the process of a working face passing through abandoned roadways,these structures are prone to varying degrees of damage,with frequent occurrences of roof leakage and induced rock burst accidents,significantly impacting subsequent mining operations and safe production.To address these issues,this study investigates the surrounding rock deformation patterns during fully mechanized mining face passage through abandoned roadway clusters.Specific countermeasures were systematically summarized according to different occurrence characteristics of abandoned roadways.Through mechanical analysis,the critical unstable width of coal pillars was determined to be approximately 16.1~16.8 m.A three-dimensional numerical model was established based on 17 abandoned roadways with various shapes and occurrences in the working face.Simulation results indicate severe deformation and failure in roof rock layer roadways,while floor roadways exhibit relatively minor damage.Notably,when the distance between abandoned roadways and the coal seam exceeds 8 m,almost no damage occurs.Three technical measures for passing through abandoned roadway group was proposed according to their occurrence characteristics and implemented in engineering practice.Field applications demonstrate limited coal stress variations and weak strata pressure manifestations during the crossing process,ensuring safe passage through abandoned roadway clusters.This achievement enables efficient and safe crossing of abandoned roadway group in fully mechanized mining faces,enhances coal recovery rates,and provides practical engineering references for similar geological conditions. 展开更多
关键词 Abandoned roadway group 3D abandoned roadway model Numerical simulation Control strategies Engineering application
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Value Evaluation for Urban Medical Groups in China:A Case From Dapeng New District in Shenzhen
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作者 Yan Cui Leiyu Shi +2 位作者 Shilan Tang Yansui Yang Lijie Ren 《Health Care Science》 2025年第3期206-214,共9页
Background:An urban medical group in Dapeng New District was established in 2017 with the objective of enhancing outcomes for common diseases and reinforcing primary care by integrating high‐level hospitals with prim... Background:An urban medical group in Dapeng New District was established in 2017 with the objective of enhancing outcomes for common diseases and reinforcing primary care by integrating high‐level hospitals with primary health services.This study aimed to evaluate the performance of the urban medical group using the triangular value chain framework.Methods:The evaluation was conducted using the Donabedian model,focusing on three key dimensions:safety and quality,accessibility,and affordability.Longitudinal data were collected from 2016 to 2022 through government annual reports,the medical insurance bureau,and hospital information systems.Preprogram and postprogram outcome measurements were compared to assess differences and trends,providing a clear picture of the program's effectiveness.Results:Accessibility improved significantly,with the number of hospital beds per 1000 residents increasing from 2.62 in 2017 to 3.76 in 2022.The availability of general practitioners(GPs)also rose markedly,from 0 per 10,000 residents in 2017 to 6.27 in 2022.Regarding safety and quality,the proportion of complex medical procedures conducted within the New District expanded substantially,from 7.35%in 2017 to 38.11%in 2021.Additionally,there was an enhancement in the standardized management rate of chronic diseases.Affordability assessments showed that the proportion of medical income derived from the medical insurance fund increased by nearly 22.81 percentage points between 2012 and 2021.By 2021,75.02%of medical patients were covered by medical insurance,representing an increase of approximately 44 percentage points from 31.19%in 2012.Conclusions:The implementation of the urban medical group in Dapeng New District has led to substantial improvements in healthcare accessibility,safety and quality,and affordability.Future initiatives will focus on advancing the“Dapeng Mode”to generate exemplary healthcare outcomes and minimize disparities in basic health services and health status between urban and rural populations.The reform agenda includes piloting payment reforms and innovative payment models within the Dapeng group,complemented by a health assessment and performance incentive system aimed at encouraging healthcare institutions to prioritize health management. 展开更多
关键词 Donabedian model integrated care medical consortium triangular value chain triple aims urban medical group value evaluation
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Impact of Consanguineous Marriage on Hearing and Language Disorders:Study Among a Group of Egyptian Children
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作者 Sherien A.Nasser Fatma Hussein +1 位作者 Heba Tallah Sherif Abd El Hady Nagwa A.Meguid 《Journal of Otology》 2025年第2期110-116,共7页
Background:Even though various research has demonstrated the connection between consanguinity and health issues,consanguineous marriage still common in Egypt with high prevalence rate 35.3%,23.5%in semi-urban and 17.7... Background:Even though various research has demonstrated the connection between consanguinity and health issues,consanguineous marriage still common in Egypt with high prevalence rate 35.3%,23.5%in semi-urban and 17.7%in urban areas.Methods:This study was conducted on 434native Arabic-speaking Egyptians children(3-10 years)who visited Special Needs Clinic at National Research Centre,among one year presenting with a hearing or/and language problem.They were subjected to psychometric assessment,Conners'Parent Rating Scales-Revised,Autism Diagnostic Interview Revised,Childhood Autism Rating Scale,audiological assessment,and Arabic Preschool Language Scale-4.Participants were classified into 6 subgroups according to the cause of language delay.We estimated the frequency and degree of consanguinity in each group and the association between consanguinity and hearing and language problems.Results:The prevalence of the consanguineous marriage in all participants(n=434)was31.6%with the mean inbreeding coefficient of 0.01208.First cousins'marriages were the most common type of consanguineous marriages(50.3%of consanguineous marriages).Among all participants in the 6 subgroups(n=434),language delay secondary to cognitive delay showed the highest percentage of consanguineous marriages(35%)followed by autism spectrum disorder(32.8%).No significant association between consanguinity and language problems.Among the 78 participants with sensorineural hearing loss,35.9%of consanguineous couples(no.=28 cases)were reported versus 64.1%of non-consanguineous couples(no.=50 cases).Conclusions:The Frequency of consanguineous marriages in our participants was 31.6%which was close to that reported in Egyptian population.Absence of significant association between consanguinity and language problems warrants further investigation and point to the role of genetic-environment interplay in cases of language delay. 展开更多
关键词 Consanguineous MARRIAGE HEARING LANGUAGE EGYPTIAN CHILDREN
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Synthesis,Performance,and Mechanism of Polycarboxylate Superplasticizers Containing Adsorption Groups
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作者 GUO Haoping WANG Peng +10 位作者 CHEN Jiang ZHU Yiping SHEN Xuetao LOU Rongrong ZHU Senjie XU Xingen LIU Yuan LIU Ke SONG Shaomin LI Fei GE Dongliang 《Journal of Wuhan University of Technology(Materials Science)》 2025年第3期780-791,共12页
This article presents a preparation method for a tailing sand-specific polycarboxylate superplasticizer(AT9)containing multifunctional adsorption groups.By designing multifunctional adsorption groups(-COOH)as side cha... This article presents a preparation method for a tailing sand-specific polycarboxylate superplasticizer(AT9)containing multifunctional adsorption groups.By designing multifunctional adsorption groups(-COOH)as side chains grafted onto the main chain of conventional polycarboxylate ether,the antiadsorption effect is achieved.AT9 was characterized by gel permeation chromatography,and its performance was systematically evaluated in various tailings sand-cement mortar systems.A comparison was made between AT9 and traditional PCE in terms of their effects on the workability of concrete,and the interaction mechanism between AT9 and clay in cementitious systems was discussed.The results indicate that AT9 enhances the adsorption and dispersion effects of polycarboxylate superplasticizers on cement particles,and increases steric hindrance,thereby avoids intercalation adsorption of tailings sand,improves its water-reducing and slump-retaining performance,and also contributes to the strength enhancement of concrete in later stages. 展开更多
关键词 polycarboxylate superplasticizer molecular design tailings sand highly adsorptive CONCRETE
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Trends in prevalence and burden of depressive disorders in Iran at national and subnational levels: estimates based on sex and age groups
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作者 Sohrab Amiri Moien A B Khan 《General Psychiatry》 2025年第3期199-207,共9页
Background Mental disorders rank among the leading contributors to the global disease burden, with depressive disorders being among the most prevalent.Aims The objective of this study is to examine the prevalence, inc... Background Mental disorders rank among the leading contributors to the global disease burden, with depressive disorders being among the most prevalent.Aims The objective of this study is to examine the prevalence, incidence and years lived with disability (YLDs) associated with depressive disorders, particularly major depressive disorder and dysthymia, in Iran from 1990 to 2021. To achieve this, the research focused on analysing these metrics across various dimensions, including temporal trends, sex differences, age categories and subnational regions.Methods The data used in this study are sourced directly from the Institute for Health Metrics and Evaluation, ensuring that the information is both authoritative and reliable. All-age count estimates and age-standardised rates (per 100 000) were calculated for prevalence, incidence and YLDs. The disease burden indicators were analysed for the period spanning from 1990 to 2021, stratified by sex, age and location. The percentage change between 1990 and 2021 was also documented. The 95% uncertainty interval (UI) was reported for each of the reported estimates.Results The prevalence of depressive disorders in Iran demonstrated a notable upward trend from 1990 to 2021, with the rate of growth being particularly pronounced within the country. The age-standardised prevalence rate per 100 000 individuals for depressive disorders in Iran was 5609 (95% UI 4810 to 6488). By 2021, the number of depression cases in Iran reached 5.2 million, which is approximately 2.37 times the figure reported in 1990. The prevalence of depressive disorders was notably higher among females compared with males. The age-standardised prevalence rate per 100 000 individuals for males was 4184 (95% UI 3545 to 4929). For females, this figure was significantly greater, reaching 7077 (95% UI 6115 to 8172). Out of the total reported cases of depressive disorders in Iran, 3.2 million were observed in females, while males accounted for 2 million cases.Conclusions The findings highlighted the considerable impact of depressive disorders in Iran, both nationally and regionally, while also revealing variations across sex and age groups. Given the shifts in the demographic structure and the growing burden of these disorders, it is essential to prioritise screening initiatives, education programmes and strategies aimed at enhancing mental health awareness and ensuring improved access to mental health services in health policy planning. 展开更多
关键词 years lived disability sex differences Iran major depressive disorder BURDEN PREVALENCE depressive disorders mental disorders
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VANET Security through Group Broadcast Encryption
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作者 Eric Eduardo Bunese Eduardo Todt Luiz Carlos Pessoa Albini 《Journal of Computer and Communications》 2020年第8期22-35,共14页
VANET security is an evolving topic in mobile networks, as providing a secure layer of communications in such a dynamic and fast network is a challenge. The work presented in this article was conducted in order to ver... VANET security is an evolving topic in mobile networks, as providing a secure layer of communications in such a dynamic and fast network is a challenge. The work presented in this article was conducted in order to verify and evaluate the feasibility of applying group broadcast cryptography to the VANET environment, as an attempt to gain performance by decreasing the number of messages in the wireless network. Group broadcast is a symmetric/asymmetric hybrid cryptography method, aiming to merge the best of the two approaches without their major drawbacks. Simulations were set-up and run using the ONE simulator, comparing the usage of the three different cryptography approaches for VANETs. Results consider the number of connections, the number messages and the number of revocation messages per day. The resulting data promises that group broadcast encryption can be used to simplify the encrypting phase, reduce required storage and significantly decrease the number of messages in the network. 展开更多
关键词 VANET Security Group Broadcast Encryption Group Based VANET
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Group Ⅷ elements-based single-atom electrocatalysts for energy conversion:a mini review
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作者 Lei Zhang Mao-Lin Li +6 位作者 San-Shuang Gao Xin-Zong Wang Xi-Jun Liu Yu-Jie Ma Guo-You Cheng Xu-Guang An Guang-Zhi Hu 《Rare Metals》 2025年第7期4532-4550,共19页
Electrochemical reduction reactions,including the oxygen reduction reaction(ORR),hydrogen evolution reaction(HER),carbon dioxide reduction reaction(CRR),and nitrate reduction reaction(NRR),hold promise for energy conv... Electrochemical reduction reactions,including the oxygen reduction reaction(ORR),hydrogen evolution reaction(HER),carbon dioxide reduction reaction(CRR),and nitrate reduction reaction(NRR),hold promise for energy conversion and storage.However,electrocatalysts exhibit slow kinetics and inactivation effects,resulting in inadequate energy efficiency and poor stability.To address these challenges,the groupⅧelement-based single-atom electrocatalysts(GVSAEs)were endowed with tunable electronic structures and porous carbon substrates to reduce intermediate adsorption and desorption energy barriers,which can accelerate electrochemical kinetics.This mini review summarises the recent achievements in GVSAEs with electronic structure and porous substrate engineering discussions.Furthermore,these GVSAEs are divided into non-noble iron series element(Fe,Co,and Ni)single-atom electrocatalysts and noble platinum series elements(Ru,Rh,Pd,Os,Ir,and Pt)based single-atom electrocatalysts for the ORR,HER,CRR,and NRR,where the porous substrate structure,electronic structure,and catalytic activity are discussed.Finally,conclusions and perspectives relating to future challenges and potential opportunities are provided for electrocatalysis with better performance. 展开更多
关键词 Oxygen reduction reaction Hydrogen evolution reaction Carbon dioxide reduction reaction Nitrate reduction reactions Single-atom electrocatalysts
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Finite Groups Whose Some Subgroups Are S-seminormal
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作者 王坤仁 《Northeastern Mathematical Journal》 CSCD 2004年第2期217-224,共8页
A subgroup H is called S-seminormal in a finite group G if H permutes with all Sylow p-subgroups of G with (p, |H| =1. The main object of this paper is to generalize some known results about finite supersolvable group... A subgroup H is called S-seminormal in a finite group G if H permutes with all Sylow p-subgroups of G with (p, |H| =1. The main object of this paper is to generalize some known results about finite supersolvable groups to a saturated formation containing the class of finite supersolvable groups. 展开更多
关键词 saturated formation generalized Fitting subgroup S-seminormal subgroup
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A Sufficient Condition for Mi-groups
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作者 何立国 朱刚 《Northeastern Mathematical Journal》 CSCD 2003年第4期371-374,共4页
In this note, we give a sufficient condition for Mi-group. In particular, we show that if a finite group G is the semidirect product of two subgroups with coprime orders, in which one is a Sylow tower group and its Sy... In this note, we give a sufficient condition for Mi-group. In particular, we show that if a finite group G is the semidirect product of two subgroups with coprime orders, in which one is a Sylow tower group and its Sylow subgroups are all abelian, and the other is an Mi-group and all of its proper subgroups are also Mi-groups, then G is an Mi-group. 展开更多
关键词 solvable group Mi-group semidirect product
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A review of the Birimian Supergroup-and Tarkwaian Group-hosted gold deposits of Ghana
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作者 Albertus J.B.Smith George Henry Susan Frost-Killian 《Episodes》 2016年第2期177-197,共21页
Ghana is the largest producer of gold in West Africa,a region with over 2,500 years of history with regards to gold production and trade.Modern exploration for and mining of gold in Ghana dates from 1874 with the esta... Ghana is the largest producer of gold in West Africa,a region with over 2,500 years of history with regards to gold production and trade.Modern exploration for and mining of gold in Ghana dates from 1874 with the establishment of the British Gold Coast Colony,which was followed in 1957 by the independence of Ghana and increased gold production since the early 1980s through Ghana’s Economic Recovery Plan.At the time of writing,gold production(108.2 tonnes or 3.48 million ounces[Moz]in 2014)accounted for approximately one-third of Ghana’s export revenues,with 36%of gold production coming from small-scale mining. 展开更多
关键词 Birimian Supergroup gold production Ghana gold deposits small scale mining Tarkwaian Group
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Stability control of gate groups in deep wells 被引量:8
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作者 GUO Zhi-biao GUO Ping-ye +1 位作者 HUANG Mao-hong LIU Yin-gen 《Mining Science and Technology》 EI CAS 2009年第2期155-160,共6页
In order to study stability control methods for a deep gate group under complex stresses,we conducted field investigations and analyses of reasons for damage in the Xuzhou mining district.Three reasons are proposed:de... In order to study stability control methods for a deep gate group under complex stresses,we conducted field investigations and analyses of reasons for damage in the Xuzhou mining district.Three reasons are proposed:deep high stress,improper roadway layout and support technology.The stability control countermeasures of the gate group consist of an intensive design technology and responding bolt-mesh-anchor truss support technology.Our research method has been applied at the -1000 m level gate group in Qishan Coal Mine.Suitable countermeasures have been tested by field monitoring. 展开更多
关键词 deep gate group stability intensive design bolt-mesh-anchor truss support
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Petrology of Garnet Amphibolites from the Hualong Group: Implications for Metamorphic Evolution of the Qilian Orogen, NW China 被引量:3
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作者 Yilong Li Limin Zhao +3 位作者 Zhuoyang Li Biji Luo Jianping Zheng Fraukje M.Brouwer 《Journal of Earth Science》 SCIE CAS CSCD 2018年第5期1102-1115,共14页
The Qilian Orogen marks the junction of the North China, South China and Tarim cratons. The mechanism of continental growth during the formation of the orogen remains unclear. Based on detailed fieldwork, we present a... The Qilian Orogen marks the junction of the North China, South China and Tarim cratons. The mechanism of continental growth during the formation of the orogen remains unclear. Based on detailed fieldwork, we present a systematic study of petrography, mineral chemistry and phase equilibria of garnet amphibolites from the Hualong Group, which represents the Precambrian basement in the southern accretionary belt of the Qilian Orogen. The garnet amphibolites mainly consist of amphibole, plagioclase, garnet and quartz, with minor pyroxene, biotite and ilmenite. A peak stage of upper amphibolite facies to low-temperature granulite facies metamorphism and retrograde metamorphism in the amphibolite facies affected the samples. Garnet has a homogeneous composition of Alm66-71Grs14-17Prp9_12Sps3-s, amphibole is ferro-hornblende, biotite belongs to the ferro-biotite species and pyroxene is dominated by orthopyroxene with few clinopyroxene. Pseudosection modeling of the garnet amphibolite samples indicates clockwise P-T paths. The samples witness peak metamorphism at conditions of -4.9-6.3 kbar and -755-820 ℃ in the upper amphibolite facies to low- temperature granulite facies, and retrograde cooling and decompression at conditions of-2.5-3.1 kbar and -325-545 ℃. It is inferred that peak metamorphism with high temperature and low pressure occurred at ca. 450 Ma during northward subduction of the South Qilian oceanic crust beneath the central Qilian Block. When continental collision occurred between the central Qilian and the Qaidam blocks, the Hualong Block was aecreted onto the South Qilian accretionary complex and experienced amphibolite facies retrograde metamorphism at ca. 440 Ma. 展开更多
关键词 Qilian Orogen Hualong Group garnet amphibolite PETROLOGY metamorphic P-T path PerpleX.
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Molecular characterization of VP4,VP6,VP7 and NSP4 genes of group B rotavirus strains from outbreaks of gastroenteritis 被引量:1
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作者 Anismrita Lahon Shobha D Chitambar 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第11期846-849,共4页
Objective:To characterize VP4,VP6,VP7 and NSP4 genes of representative GBR strains(NIV- 005625.MV-04622 and NIV-094456) delected as the major eliolngic agenl in the outbreaks of gastroenteritis in western India.Method... Objective:To characterize VP4,VP6,VP7 and NSP4 genes of representative GBR strains(NIV- 005625.MV-04622 and NIV-094456) delected as the major eliolngic agenl in the outbreaks of gastroenteritis in western India.Methods:Fecal specimens collected during the outbreaks of gastroenteritis were processed for RNA isolation.RT-PCR using GBR VP4.VP6.VP7 and NSP4 gene specific primers,nucleotide sequencing of the amplicons and phylogenetic analysis of the sequences.Results:Phylogenetic analysis of all of the VP4.VP6.VP7 and NSP4 gene sequences revealed clustering of GBR strains in Indian-Bangladeshi lineage of genotype G2 with 95.8%- 99.4%nucleotide and 97.3%-100.0%amino acid identities.However,all three strains showed the presence of unique amino acid substitutions in the VP4 protein suggesting alteration in the antigenicity of outbreak strains of GBR.The VP8* and VP5* regions of VP4 proteins showed respectively 0.5%-6.3%and 0.2%-1.1%amino acid divergence from human GBR strains of Indian-Bangladeshi lineage.Conclusions:These data confirm the reported variability of VP8* region and suggest the possible role of this region in the perpetuation of GBR infections in the environment.This is the first study to document the phylogenetic relationship of VP4,VP6.VP7 and NSP4 genes of GBR strains detected in the outbreaks of gastroenteritis from India with the CBR strains from other parts of world. 展开更多
关键词 Acute GASTROENTERITIS GROUP B ROTAVIRUS VP4 VP6 VP7 NSP4
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Petrology and Metamorphic P-T Paths of Metamorphic Zones in the Huangyuan Group,Central Qilian Block,NW China 被引量:3
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作者 Zhuoyang Li Yilong Li +2 位作者 Limin Zhao Jianping Zheng Fraukje M.Brouwer 《Journal of Earth Science》 SCIE CAS CSCD 2019年第6期1280-1292,共13页
The Central Qilian Block is a Precambrian block in the Qilian Orogen,which has long drawn international attention for the study of orogeny and continental dynamics.The Huangyuan Group in the Datong area is one of the ... The Central Qilian Block is a Precambrian block in the Qilian Orogen,which has long drawn international attention for the study of orogeny and continental dynamics.The Huangyuan Group in the Datong area is one of the Precambrian metamorphic basement units in the Central Qilian Block and reflects metamorphism in the Barrovian garnet zone and sillimanite zone from south to north.Based on detailed fieldwork,this study presents a systematic study of petrography,mineral chemistry and phase equilibria of schists and gneisses from the two metamorphic zones.The garnet metamorphic zone is composed of micaschist,garnet-bearing micaschist and felsic leptynite,with interlayered plagioclase amphibolite.The sillimanite metamorphic zone consists of garnet-bearing biotite micaschist,sillimanite-bearing biotite-plagioclase gneiss and felsic leptynite.Garnet from the garnet metamorphic zone shows growth zoning with increasing almandine and pyrope and decreasing spessartine from core to rim.Garnet from the sillimanite metamorphic zone is almost homogeneous.Towards the outer rim,the contents of almandine and pyrope slightly decrease and grossular slightly increase.Biotite in both metamorphic zones is ferro-biotite.Plagioclase is oligoclase in garnet metamorphic zone and andesine in sillimanite metamorphic zone.Phase equilibrium modeling of a sample from garnet metamorphic zone resulted in a clockwise P-T path with a prograde stage(4.5–5.0 kbar,520–530℃),a peak P stage(9.8–10.2 kbar,560–570℃),a stage of thermal relaxation(8.0–8.5 kbar,580–590℃)and finally a retrograde stage(6.8–7.0 kbar,560–580℃).Thermodynamic modeling of a sample from the sillimanite metamorphic zone indicates a prograde stage(5.5–6.0 kbar,540–550℃)and a peak stage(7.8–8.5 kbar,660–690℃).The results indicate that the Huangyuan Group experienced medium-pressure amphibolite-facies metamorphism,which resulted from continental-continental collision between the Qaidam Block and the Central Qilian Block. 展开更多
关键词 QILIAN BLOCK Huangyuan GROUP garnet ZONE SILLIMANITE ZONE P-T path thermodynamic modeling
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Excavation influence of triangular-distribution tunnels for wind pavilion group of a metro station 被引量:2
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作者 CHEN Tao ZHOU Kun +4 位作者 WEI Jun LIU Xiao-chun LIN Yu-liang ZHANG Jian SHEN Quan 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第12期3852-3874,共23页
For the Guanshui Road Station tunnel project of Guiyang Metro Line 2,the wind pavilion group was moved out of the main tunnel to reduce the number of openings in the main tunnel,and the wind pavilion group was excavat... For the Guanshui Road Station tunnel project of Guiyang Metro Line 2,the wind pavilion group was moved out of the main tunnel to reduce the number of openings in the main tunnel,and the wind pavilion group was excavated in a triangular configuration at the entrance of the main tunnel.Based on the finite element software ABAQUS,a three-dimensional model is established to study the influence of different triangular-distribution tunnels excavation schemes on the surface settlement and tunnel stability.The objective of this study is to reveal the change rules of surface settlement,deformation and force in the support structures and the surrounding rock and identify the best excavation scheme for this tunnel configuration.Results show that to control the surface settlement and the deformation of the support structures,the optimal excavation sequence involves excavating the upper fresh air exhaust tunnel before the lower running tunnel.To control the stress of the support structures,the optimal excavation involves excavating the lower running tunnel before the upper fresh air exhaust tunnel.In this project,the most reasonable excavation sequence of the tunnel is from top to bottom.The most reasonable thickness of tunnel penetration is 5 m. 展开更多
关键词 station tunnel wind pavilion group finite element analysis tunnel and surrounding rock deformation stress analysis
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DYNAMIC FOR A STOCHASTIC MULTI-GROUP AIDS MODEL WITH SATURATED INCIDENCE RATE 被引量:2
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作者 Qixing HAN Daqing JIANG 《Acta Mathematica Scientia》 SCIE CSCD 2020年第6期1883-1896,共14页
In this paper,a stochastic multi-group AIDS model with saturated incidence rate is studied.We prove that the system is persistent in the mean under some parametric restrictions.We also obtain the sufficient condition ... In this paper,a stochastic multi-group AIDS model with saturated incidence rate is studied.We prove that the system is persistent in the mean under some parametric restrictions.We also obtain the sufficient condition for the existence of the ergodic stationary distribution of the system by constructing a suitable Lyapunov function.Our results indicate that the existence of ergodic stationary distribution does not rely on the interior equilibrium of the corresponding deterministic system,which greatly improves upon previous results. 展开更多
关键词 multi-group AIDS model Lyapunov function stationary distribution persistence in the mean
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Studies on Partial Molar Volumes of Some Amino Acids and Their Groups in Aqueous Solutions from 293.15K to 333.15K 被引量:1
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作者 赵长伟 马沛生 夏淑倩 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第4期521-526,共6页
Densities of aqueous solutions of eight amino acids, glycine, L-alanine, L-valine, L-isoleucine, L-serine, L-threonine, L-arginine and L-phenylalanine, are measured as a function of amino acid concentration from 293.1... Densities of aqueous solutions of eight amino acids, glycine, L-alanine, L-valine, L-isoleucine, L-serine, L-threonine, L-arginine and L-phenylalanine, are measured as a function of amino acid concentration from 293.15K to 333.15K. These data are used to calculate the apparent molar volume Vφ and infinite dilution apparent molar volume Vφo (partial molar volume). Data of five amino acids are used to correlate partial molar volume Vφo usinggroup contribution method to estimate the contributions of the zwitterionic end groups (NH3+,COO-) and CH2 group, OH group, CNHNHNH2 group and C6H5(phenyl) group of amino acids. The results show that Vφo values for all kinds of groups of amino acids studied increase with increase of temperature except those for CH2 group, which are almost constant within the studied temperature range. Data of other amino acids, L-valine, L-isoleucine and L-threonine, are chosen for comparison with the predicted partial molar volume Vφo using the group additivity parameters obtained. The results confirm that this group additivity method has excellent predictive utility. 展开更多
关键词 partial molar volume amino acid group contribution
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Effect of PCEs with Different Functional Groups on the Performance of Cement Paste 被引量:3
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作者 HE Yan ZHANG Xiong +5 位作者 WANG Yiting KONG Yaning JI Tao SHUI Liangliang WANG Xiaofu WANG Haoren 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第5期1163-1169,共7页
The adsorption behaviors and dispersing properties of polycarboxylate superplasticizer(PCE) with different functional groups were systematically analyzed to reveal the theory and methods of modifying PCE molecular str... The adsorption behaviors and dispersing properties of polycarboxylate superplasticizer(PCE) with different functional groups were systematically analyzed to reveal the theory and methods of modifying PCE molecular structures and regulating PCE performances. By substituting carboxylic groups with sulfonic groups, ester groups or acylamino groups, respectively, modified PCEs with different functional groups were synthesized. Results show that introducing low amount of ester groups or sulfonic groups into the PCE molecules has no negative effects on the fluidity of cement paste, while introducing acylamino groups into PCE molecules significantly weakens the fluidity of cement paste. At low amount(when the molar ratio of sodium methallyl sulfonate to TPEG is lower than 0.4), the rapid adsorption of sulfonic groups onto the cement particles contributes to the high dispersing performance of the sulfonic group modified PCEs. When the substitution ratio of acrylic acid by sulfonic acid is higher than 0.4, the viscosity and the yield stress of cement paste increases sharply. Redundant sulfonic groups lead to the excessive charge density of the PCE, which contributes to the inhomogeneous adsorption on the cement grains and hence results in the decline of the dispersing performance. Substitution of carboxylic group by acylamino group or ester group slightly changes the viscosity as well as the yield stress of cement paste. Introducing sulfonic group into PCE molecule improves the adsorption behavior of PCEs, while introducing ester group or acylamino group into PCE depresses the adsorption properties. 展开更多
关键词 POLYCARBOXYLATE SUPERPLASTICIZER functional group adsorption behavior RHEOLOGICAL properties CEMENT HYDRATION
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Weighted Parameterized Correlation Coefficients of Indeterminacy Fuzzy Multisets and Their Multicriteria Group Decision Making Method with Different Decision Risks 被引量:1
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作者 Cheng Du Jun Ye 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第10期341-354,共14页
Real-life data introduce noise,uncertainty,and imprecision to statistical projects;it is advantageous to consider strategies to overcome these information expressions and processing problems.Neutrosophic(indeterminate... Real-life data introduce noise,uncertainty,and imprecision to statistical projects;it is advantageous to consider strategies to overcome these information expressions and processing problems.Neutrosophic(indeterminate)numbers can flexibly and conveniently represent the hybrid information of the partial determinacy and partial indeterminacy in an indeterminate setting,while a fuzzy multiset is a vital mathematical tool in the expression and processing of multi-valued fuzzy information with different and/or same fuzzy values.If neutrosophic numbers are introduced into fuzzy sequences in a fuzzy multiset,the introduced neutrosophic number sequences can be constructed as the neutrosophic number multiset or indeterminate fuzzy multiset.Motivated based on the idea,this study first proposes an indeterminate fuzzy multiset,where each element in a universe set can be repeated more than once with the different and/or identical indeterminate membership values.Then,we propose the parameterized correlation coefficients of indeterminate fuzzy multisets based on the de-neutrosophication of transforming indeterminate fuzzy multisets into the parameterized fuzzy multisets by a parameter(the parameterized de-neutrosophication method).Since indeterminate decision-making issues need to be handled by an indeterminate decision-making method,a group decision-making method using the weighted parameterized correlation coefficients of indeterminate fuzzy multisets is developed along with decision makers’different decision risks(small,moderate,and large risks)so as to handle multicriteria group decision-making problems in indeterminate fuzzy multiset setting.Finally,the developed group decision-making approach is used in an example on a selection problem of slope design schemes for an open-pit mine to demonstrate its usability and flexibility in the indeterminate group decision-making problem with indeterminate fuzzy multisets. 展开更多
关键词 Indeterminate fuzzy multiset parameterized correlation coefficient multicriteria group decision making neutrosophic number slope design scheme
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