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Evidence of a Cadomian arc in the northern margin of Gondwana:The Ediacaran-Cambrian Mahabad rhyolitic complex,NW Iran
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作者 Rana Noori Asl Mohssen Moazzen 《Acta Geochimica》 2025年第3期609-630,共22页
The Mahabad rhyolitic complex,mostly composed of rhyolite but also including granite and granodiorite,is exposed in NW Iran as a part of the Central Iran Block.Porphyritic,hyalo-porphyritic and spheroidal are the main... The Mahabad rhyolitic complex,mostly composed of rhyolite but also including granite and granodiorite,is exposed in NW Iran as a part of the Central Iran Block.Porphyritic,hyalo-porphyritic and spheroidal are the main textures of the studied samples of rhyolite.U-Pb zircon chronology on three samples of Mahabad rhyolitic complex yielded Cambrian to Ediacaran ages of 537.6±6.6 Ma,547.4±6.5 Ma and 556.2±7.1 Ma.Based on geochemical analyses,the original magma was high potassium calc-alkaline to shoshonitic.The rocks are enriched in LREEs relative to HREEs.Trace element patterns of Mahabad rhyolite normalized to chondrites show negative anomalies of high-fi eld-strength elements(Ti,Nb,Ta,Hf,Yb,Y and Zr)and high LREEs and large ion lithophile element contents(Rb,K,Th and Ba).^(208)Pb/^(204) Pb(36.7219–39.0367),^(207) Pb/^(204) Pb(15.4963–15.7669)and ^(206) Pb/^(204) Pb(16.9405–19.9567)ratios indicate an EM-II enriched mantle source for the rhyolite magma.Large variation ofεHf(t)from−5.2 to+4.5 points to a mantle source with crustal material contribution in the magma genesis.The rhyolitic magma erupted in an active continental margin.The formation of calc-alkaline high potassium magma was probably related to metasomatism of the mantle because of the north to south subduction of Proto-Tethys oceanic crust beneath the northern margin of Gondwana continental crust. 展开更多
关键词 RHYOLITE GONDWANA Volcanic arc CADOMIAN Proto-Tethys Mahabad NW iran
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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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Seroepidemiological Assessment of Bordetella pertussis in Jahrom,Southern Iran:A Cross-Sectional Study
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作者 Rahim Raufi Fatemeh Zareian-Jahromi +2 位作者 Saba Zangeneh Jalil Rajabi Reza Shahriarirad 《Health Care Science》 2025年第1期44-51,共8页
Background:Bordetella pertussis,the causative agent of whooping cough,is a significant contributor to recurrent persistent cough across all age groups,including vaccinated individuals.This seroepidemiological study ai... Background:Bordetella pertussis,the causative agent of whooping cough,is a significant contributor to recurrent persistent cough across all age groups,including vaccinated individuals.This seroepidemiological study aims to address the gap in understanding pertussis incidence by investigating its occurrence in individuals with persistent cough and describing the characteristics of affected patients admitted to clinical centers in Jahrom,Southwest Iran.Methods:This cross-sectional study enrolled 110 patients with a cough persisting for at least 2 weeks,admitted to clinical centers in Jahrom,Iran.Blood samples were collected at baseline and on day 21 of follow-up.Serum samples were analyzed for anti-pertussis toxin immunoglobulin G(anti-PT-IgG)levels using an enzyme-linked immunosorbent assay.Demographic factors,including age,gender,occupation,area of residence,and family size,were also evaluated.Results:Among the 110 participants,77(70%)were female,and seven patients(6.4%)tested seropositive for anti-PT-IgG.No significant associations were observed between pertussis incidence and the analyzed variables,including age,gender,occupation,area of residence(urban vs.rural),and family size(p>0.05).These findings underscore the importance of enhancing vaccination coverage to reduce the prevalence of B.pertussis in the community.Conclusion:This study highlights the occurrence of pertussis in individuals presenting solely with a persistent cough,absent of classic symptoms.The findings emphasize the need for healthcare providers to conduct detailed assessments and utilize rapid diagnostic methods for timely detection.This is particularly crucial in regions with high vaccination rates but limited awareness of pertussis recurrence. 展开更多
关键词 Bordetella pertussis iran SEROEPIDEMIOLOGY
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Polymorphic variants of ABCA1, PMM2, and ARHGEF12 genes and the risk of glaucoma in an Iranian population
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作者 Asghar Shayannia Kobra Foroughi +2 位作者 Mohammad Hassan Emamian Hassan Hashemi Akbar Fotouhi 《International Journal of Ophthalmology(English edition)》 2025年第5期846-852,共7页
AIM:To examine whether rs2472493 and rs248032 in the ABCA1 gene,rs3785176 in the PMM2 gene,and rs11827818 in the ARHGEF12 gene contribute to primary open angle glaucoma(POAG)in an Iranian population.METHODS:Totally 82... AIM:To examine whether rs2472493 and rs248032 in the ABCA1 gene,rs3785176 in the PMM2 gene,and rs11827818 in the ARHGEF12 gene contribute to primary open angle glaucoma(POAG)in an Iranian population.METHODS:Totally 82 POAG patients and 172 healthy controls were enrolled.The selected gene polymorphisms were analyzed using TaqMan SNP Genotyping Assay using deoxyribonucleic acid(DNA)extracted from blood samples.Allelic and genotypic frequencies were evaluated using the Chi-square test.The association between the genotypes of single nucleotide polymorphisms(SNPs)and POAG was assessed using multiple logistic regression models.The linkage disequilibrium and haplotype block structure were assessed using the Haploview 4.2 software.RESULTS:The results showed a significant association between allele frequencies of rs2472493 in the ABCA1 gene locus and POAG[odds ratio(OR)=1.58,95%confidence intervals(CI)=1.04-2.39,P=0.031].The rs3785176 in the PMM2 gene was also associated with POAG in additive and over dominant genotypes.Moreover,haplotype analysis showed a significant association of two estimated haplotypes of rs2472493/rs2487032 with POAG.The AA haplotype showed a reduction in POAG risk(OR=0.41,95%CI=0.202-0.834,P=0.012),while the GG haplotype was associated with the disease.In addition,this study could not discover any association between genotype and allele frequency of rs248032 in the ABCA1 gene,and rs11827818 in ARHGEF12 gene and POAG.CONCLUSION:rs2472493 in the ABCA1 gene can be considered a genetic susceptibility locus for POAG.The haplotype constructed with ABCA1 gene SNPs(rs2472493/rs2487032)is associated with POAG. 展开更多
关键词 ABCA1 PMM2 ARHGEF12 rs2472493 rs248032 rs3785176 rs11827818 iran primary open angle glaucoma
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Kink-band Kinematic Analysis and its Implications for Late-stage Deformation in the Internal Parts of the Zagros Collision(Sanandaj–Sirjan Zone) in West Iran
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作者 Maryam HEYDARI Mahdi BEHYARI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第4期921-935,共15页
In the internal parts of the Zagros collision zone, several deformation phases have been superimposed. The early deformation phase caused the development of a penetrative foliation. The late-stage deformation phase wa... In the internal parts of the Zagros collision zone, several deformation phases have been superimposed. The early deformation phase caused the development of a penetrative foliation. The late-stage deformation phase was preferentially accommodated within shear zones and caused the generation of shear bands, implying a non-coaxial component of deformation, the end of this stage deformation was marked by the development of kink-bands. In the vicinity of Zagros suture zone, the kink angle increased from 40° to 60°, and the kink-bands was converted to chevron folds. In this region, the external(α) and internal(β) angular ratio is α/β ≠ 1 and kink angle increased, and deformation occurred with 10% to 30% volume loss. Farther from the suture zone in the east, α/β = 1;and total volume was constant or increased by 5% to 10%. Kink-bands kinematic analysis in the study area revealed this structures were sensitive to deformation conditions and components such that, with decreasing distance to the Zagros suture zone, shearing and rotation increased, a high kinematic vorticity dominated, and volume loss occurred during deformation. 展开更多
关键词 kink-band shear zone strain VORTICITY ZAGROS iran
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Petrologic evolution of the Gysian ophiolitic serpentinites,NW Iran
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作者 Monir Modjarrad Donna L.Whitney Hadi Omrani 《Acta Geochimica》 EI CAS CSCD 2024年第5期996-1011,共16页
The Gysian ophiolite of NW Iran is located at the intersection of the ophiolite belts of SE Turkey,NE Iraq,and Iran,and provides the opportunity to investigate the preserved subduction and obduction history of an impo... The Gysian ophiolite of NW Iran is located at the intersection of the ophiolite belts of SE Turkey,NE Iraq,and Iran,and provides the opportunity to investigate the preserved subduction and obduction history of an important tectonic site that has not previously been studied.The serpentinized peridotites of the Gysian ophiolite contain the assemblagelizardite+chrysotile+spinel/Mg-spinelwith relict clinopyroxene(diopside)and very rare relict orthopyroxene and olivine.The compositions of clinopyroxenes and spinels are more consistent with the formation of the inferred protolithharzburgitesinafore-arcorsupra-subduction zone instead of an abyssal environment.The Gysian ophiolite is a remnant of the Neo-Tethyan arc-ophiolitic system and records shallow subduction(<50 km,indicated by the absence of antigorite)in the Late Cretaceous to Paleocene beforeobductionalongthrustfaultsoverthecontinental margin.We review the spatial trends of the metamorphic grade of the Neo-Tethyan ophiolites in this region and provide detailed information about the petrology and mineral chemistry of the Gysian ophiolite. 展开更多
关键词 OPHIOLITE Neo-Tethyan Gysian SERPENTINITE iran
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Depositional and Bio-Sequence Stratigraphic Framework of Late Cretaceous Kawagarh Formation,Kala-Chitta Range,Pakistan:Equivalent of Gurpi Formation(Iran)
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作者 Muhammad Awais Bilal Wadood +4 位作者 Muhammad Ishaq Muhammad Bilal Zeeshan Zafar Nasar Khan Aminullah Khan 《Journal of Earth Science》 SCIE CAS CSCD 2024年第2期332-348,共17页
The present study is focused on evaluation of deep marine pelagic sediments of Late Cretaceous Kawagarh Formation of Kala-Chitta Range in the context of microfacies analysis,paleoenvironmental interpretation,planktoni... The present study is focused on evaluation of deep marine pelagic sediments of Late Cretaceous Kawagarh Formation of Kala-Chitta Range in the context of microfacies analysis,paleoenvironmental interpretation,planktonic foraminiferal biostratigraphy,sequence stratigraphy and diversification of species.A total of thirty three rock samples were collected from the measured section.Three microfacies are interpreted,namely planktonic foraminifera wackestone,planktonic foraminifera mudstone and sandy mudstone indicating low energy depositional environment i.e.,outer ramp.The biostratigraphic studies show plentiful planktonic foraminifera species of Globotruncana,Heterohelix and Globotruncanita.However,no association of benthic or siliceous organisms was observed.On the basis of available species assemblage,a single local planktonic foraminifera biozone i.e.,Globotruncana-Heterohelix-Globotruncanita Assemblage Biozone is established.The biozone information is combined with published literature and Lower Santonian to Middle Maastrichtian age has been assigned to the Kawagarh Formation.The trend of species occurrences evinces that species number decreases over time with pulsated rise in the Kawagarh Formation.The Kawagarh Formation carbonates show an overall Transgressive Systems Tract(TST).The Kawagarh Formation of Pakistan evinces analogous characteristics to that of the Late Cretaceous Gurpi Formation of Iran based on the geologic age,outcrop lithology,microfacies,planktonic foraminiferal assemblages,depositional setting and sequence stratigraphy. 展开更多
关键词 depositional fabric BIOSTRATIGRAPHY sequence stratigraphy Late Cretaceous Kawagarh Formation Pakistan Gurpi Formation iran
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Fe-Ti Oxide Mineralization in the XV Intrusion,Bafq Mining District,Central Iran:Insights from Mineralogy,Mineral Chemistry and S Isotopic Data
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作者 Sakine Amraei Majid Ghasemi Siani +3 位作者 Mohammad Yazdi Liang Qiu Bertrand Moine Minghua Ren 《Journal of Earth Science》 SCIE CAS CSCD 2024年第5期1704-1719,共16页
The mafic-ultramafic intrusion in the XV anomaly area,contains magmatic Fe-Ti oxides±(p)ore,is located in the Bafq mining district in the Central Iran.It consists of cumulate and layered Fe-Ti-bearing gabbros and... The mafic-ultramafic intrusion in the XV anomaly area,contains magmatic Fe-Ti oxides±(p)ore,is located in the Bafq mining district in the Central Iran.It consists of cumulate and layered Fe-Ti-bearing gabbros and pyroxenites.The mineral assemblages include clinopyroxene,Fe-Ti oxides,plagioclase,amphibole,apatite and sulfides(pyrite and chalcopyrite).The Fe-Ti oxides mainly consist of magnetite-titanomagnetite and ilmenite,which occurred as disseminated,intergrowth,lamellae(trellis and sandwich textures)and inclusions.Magnetite in the gabbroic rocks is from the near end-member of Fe_(3)O_(4)(<1 wt.%TiO_(2))to titanomagnetite containing up to 8 wt.%TiO_(2)(about3.73 wt.%to 26.84 wt.%Ulvospinel(X_(Usp))).Magnetite in pyroxenite rocks is characterized with TiO_(2)range from 0.46 wt.%to 3.14 wt.%(X_(Usp)varied from 1.76 wt.%to 10.46 wt.%).The abundances of V_(2)O_(3)range from 0.03 wt.%to 1.29 wt.%and 0.24 wt.%to 1.00 wt.%for gabbro and pyroxenite,respectively.X_(Usp)contents of magnetite show insignificant correlations with Al_(2)O_(3)and MgO.The average XIlmin the ilmenite of gabbro is 92%,whereas it is 90.37%in the pyroxenite rocks.The MgO and V_(2)O_(3)contents show a slightly positive correlation with TiO_(2)in ilmenite.The composition of clinopyroxenes in gabbro and pyroxenite rocks fall in the diopside to augite field with Mg#ranging from 67 to 98 and 74 to 96,respectively.In both rock types,amphiboles are mainly pargasite and rarely actinolite.Plagioclase in pyroxenite rocks is clustered in the labradorite to andesine fields with a compositional ranges of An46-69and in gabboic rocks fall in two fields with compositional ranges of albite with An0.65-5.95and labradorite with An50-63.Theδ34S isotopic values cover a limited range from+3.15‰to+4.10‰V-CDT consistent with magmatic origin.Fe-Ti mineralization is formed in two stages,minor inclusions of Fe-Ti oxide minerals in the pyroxene and plagioclase crystallized in the early magmatic stage,whereas interstitial oxides formed by fractional crystallization processes that accumulated by gravitational settling in the later stage as intercumulus phase.Gravitational settling process is supported by the observation of decreasing the amount of Fe-Ti oxides from Fe-Ti oxide-rich pyroxenite to weak mineralized gabbro(base to top).The high contents of H2O,phosphorate and high initial Ti-Fe in parental magma are the crucial factors controlling the Fe-Ti oxides enrichment and mineralization. 展开更多
关键词 mafic-ultramafic intrusion Fe-Ti oxides gravitational settling mineral chemistry Bafq mining district Central iran mineral deposits
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A systematic review and meta-analysis of the prevalence of Leishmania infantum in sandflies in Iran
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作者 Sara Rahimi Homa Arshadi +2 位作者 Hamid Reza Shoraka Aioub Sofizadeh Arman Latifi 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第11期491-500,共10页
Objective:To determine the overall and pooled prevalence of Leishmania(L.)infantum in sandfly vectors in Iran.Methods:The present research conducted a systematic review and meta-analysis and searched regional database... Objective:To determine the overall and pooled prevalence of Leishmania(L.)infantum in sandfly vectors in Iran.Methods:The present research conducted a systematic review and meta-analysis and searched regional databases such as PubMed,Scopus,Web of Science(WoS),Embase,PAHO Iris,LILACS,WHO Iris,and local databases named:SID,Magiran,Civilica,and also grey literatures.The current research included studies that were conducted in Iran and examined L.infantum in different sandfly vectors.The studies’quality assessment/risk of bias assessment was evaluated by the Joanna Briggs Institute Critical Appraisal Checklist for prevalence data studies,and the data were analyzed by Stata 14 software.In addition,we examined 22 primary studies to estimate the overall prevalence of L.infantum among various vectors of visceral leishmaniasis.Results:According to the meta-analysis,the pooled prevalence of Phlebotomus(Ph.)tobbi,Ph.alexandri,Ph.kandelaki,Ph.perfiliewi,Ph.major,Ph.keshishiani were 5.34%,4.36%,2.23%,1.79%,4.37%and 1.18%.Ph.tobbi has the highest infection rate(25.00%)of L.infantum among the sandfly vectors.Conclusions:Visceral leishmaniasis is widespread in Fars,Ardebil,and East-Azerbaijan provinces,which are the most important endemic regions in Iran. 展开更多
关键词 Visceral leishmaniasis Leishmania infantum SANDFLY Systematic review META-ANALYSIS iran
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Survival and risk analysis of patients with COVID-19 in Iran
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作者 Mottaghipoor F Heidari Z +2 位作者 Sami R Memarzadeh H Saghaeiannejad Isfahani S 《Journal of Acute Disease》 2024年第2期60-66,共7页
Objective:To evaluate the risk factors of death caused by COVID-19 in Iran.Methods:This study was a retrospective cohort study from February 20,2020,to August 22,2022,in the hospitals in Isfahan,Iran.The data were col... Objective:To evaluate the risk factors of death caused by COVID-19 in Iran.Methods:This study was a retrospective cohort study from February 20,2020,to August 22,2022,in the hospitals in Isfahan,Iran.The data were collected through a researcher-made checklist.To determine the risk factors of the death,logistic regression and Cox regression models were used.For each variable,the odds ratio and 95%confidence interval were also reported.Results:1885 Patients were included.The age of deceased persons was significantly higher than that of the surviving persons.The risk of death for the age group above 60 years was about 14 times higher than that of people aged 19-35 years[95%CI:14.41(2.02-102.99),P<0.01].Hypertension[95%CI:1.92(1.47-2.5),P<0.01],diabetes[95%CI:1.62(1.23-2.13),P<0.001],and chronic obstructive pulmonary disease[95%CI:1.92(1.47-2.50),P<0.01]were also risk factors of mortality.Conclusions:This study reveals that the mortality rate due to COVID-19 is associated with old age,longer hospitalization in the ICU,increased length of stay,and comorbidities of high blood pressure,diabetes,and chronic pulmonary disease. 展开更多
关键词 CAUSE DEATH SURVIVAL COVID-19 Risk factors iran
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Spatial analysis of animal bites in Iran(2015-2020):A cross-sectional study
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作者 Hoda Amiri Khadijeh Yazdanparast +1 位作者 Mohsen Pourkhosravani Maryam Rastegar 《Journal of Acute Disease》 2024年第2期67-73,共7页
Objective:To investigate the distribution pattern of animal bites in Mirjaveh,Iran from 2015 to 2020.Methods:The data on animal bites were collected from the Department of Infectious Diseases,the provincial health cen... Objective:To investigate the distribution pattern of animal bites in Mirjaveh,Iran from 2015 to 2020.Methods:The data on animal bites were collected from the Department of Infectious Diseases,the provincial health center.Monthly climatic data on precipitation and temperature during the study period were also collected.The correlation between incidence and temperature,precipitation rate,land type,and altitude was also analyzed.Results:The results showed that men were more affected by animal bites than women(76.4%,P<0.001),and the highest incidence rate occurred in the age group of 5-19 years.The incidence rate of animal bites was found to be correlated with temperature and altitude.An increase in temperature was associated with a rise in the incidence rate of animal bites.The number of animal bites increased until 2019,possibly due to an increase in the number of dogs in the area.Conclusions:Targeted interventions should be implemented to reduce the incidence of animal bites,particularly among children,housewives,and students.Improving access to appropriate treatments,increasing public awareness of the hazards of animal bites,and increasing the number of vaccinated dogs in the area are essential strategies to be considered. 展开更多
关键词 Animal bites EPIDEMIOLOGY Zoonotic disease iran
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Identifying reservoirs in northwestern Iran using high-resolution satellite images and deep learning
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作者 Kaidan Shi Yanan Su +6 位作者 Jinhao Xu Yijie Sui Zhuoyu He Zhongyi Hu Xin Li Harry Vereecken Min Feng 《Geo-Spatial Information Science》 CSCD 2024年第3期922-933,共12页
Reservoirs play a critical role in terrestrial hydrological systems,but the contribution of small and medium-sized ones is rarely considered and recorded.Particularly in developing countries,there is a rapid increase ... Reservoirs play a critical role in terrestrial hydrological systems,but the contribution of small and medium-sized ones is rarely considered and recorded.Particularly in developing countries,there is a rapid increase of such reservoirs due to their quick construction.Accurately identifying these reservoirs is important for understanding social and economic development,but distinguishing them from other natural water bodies poses a significant challenge.Thus,we propose a method to identify reservoirs using high-resolution satellite images and deep learning algorithms.We trained models with various parameters and network structures,and You Only Look Once version 7(YOLOv7)outperformed other algorithms and was selected to build the final model.The method was applied to a region in northwestern Iran,characterized by an abundance of reservoirs of various sizes.Evaluation results indicated that our method was highly accurate(mAP:0.79,Recall:0.76,Precision:0.82).The YOLOv7 model was able to automatically identify 650 reservoirs in the entire study region,indicating that the proposed method can accurately detect reservoirs and has the potential for broader-scale surveys,even global applications. 展开更多
关键词 RESERVOIR deep learning object detection iran
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Characterizing the Provenance Signatures and Geochemical Behaviors of Turquoise in Copper Deposits:Comparative Case Studies of Meiduk,Iran,and Tongling,China
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作者 Bahareh Shirdam Mingxing Yang +2 位作者 Jia Liu Ling Liu Andy Hsitien Shen 《宝石和宝石学杂志(中英文)》 CAS 2024年第S01期71-73,共3页
Turquoise, a hydrous phosphate of copper and aluminum, is highly valued for its unique colour and historical significance. The similarity in colour, quality, and pattern between turquoises from different localities ma... Turquoise, a hydrous phosphate of copper and aluminum, is highly valued for its unique colour and historical significance. The similarity in colour, quality, and pattern between turquoises from different localities may lead to confusion in determining their origins. This is particularly evident in the case of turquoises from Meiduk in Iran and Tongling in China(Fig.1).In Iran, turquoise deposits are typically associated with magmatic zones, specifically in the Meiduk mine, located 85 kilometers northwest of the Sar Cheshmeh porphyry copper deposit in Kerman Province. The deposit is hosted by Eocene volcanic rocks of andesitic-basaltic composition with porphyry-type mineralization associated with two Miocene calc-alkaline intrusive phases. Five distinct zones of the hypogene alteration include potassic, potassic-phyllic, phyllic, and propylitic zones, which are rich in magnetite. Mineralization processes include stockwork, dissemination, veinlets, and veins rich in garnet, chalcopyrite, magnetite, and anhydrite. Turquoise is found in transitional, leached, and supergene zones, primarily as fracture and seam fillers. In contrast, Chinese turquoises are more often found in sedimentary rocks, with significant exceptions in places like the Tongling mine in Anhui Province, which are hosted within magmatic rocks. The turquoise from Tongling is found in the Tongling area within the Middle-lower Yangtze Metallogenic Belt, an area characterized by complex tectonics and intense magmatic and metallogenic activities. The turquoise deposits are associated with iron-copper polymetallic mineralization within Early Cretaceous volcanic rocks.The turquoise from Meiduk exhibited a specific gravity range of 2.22 g/cm^(3)to 2.71 g/cm^(3), SWUV fluorescence from none to medium, and LWUV fluorescence from faint to strong, indicating diverse mineralogical compositions. SEM examination of turquoise from Meiduk reveals a variety of mineral morphologies. The turquoise displays closely packed arrays of elongated needle-like crystals, measuring 2 μm to 9 μm in length and 0.1 μm to 0.4 μm in thickness, indicating a dynamic growth environment. The density and alignment of these crystals suggest the space-constrained setting, likely influenced by rapid deposition from mineral-laden fluids, with crystals interlocked due to simultaneous nucleation events. Some crystals appear similarly elongated but are more dispersed, with greater separation between individual crystals. In other areas, the elongated turquoise crystals are tightly intergrown, creating a dense textural appearance, pointing to a stage where growth space became limited, resulting in an interlocking matrix. Additionally, some crystals radiate outward from a central point, forming a spherical pattern reaching about 18 μm. The turquoise from Tongling show a specific gravity range of 2.26 g/cm^(3)to 2.60 g/cm^(3), with consistent medium SWUV fluorescence and strong LWUV fluorescence. SEM examination reveals needle structures, plate-like structures, and spheroidal aggregates composed of needle and plate-like microcrystals. These spherical aggregates, some with diameters around 26 μm, exhibit the concentric growth structure covered by turquoise microcrystals, with crystal lengths of 8 μm. The surface needle-like microcrystals vary in size, approximately 3 μm in length, 2 μm in width, and 0.2 to 0.6 μm in thickness.Optical microscopy, Raman and FTIR spectroscopy reported the presence of quartz, gypsum, iron oxides such as jarosite and goethite, biotite, sericite, pyrite, galena, bornite, graphene oxide, malachite, and azurite as major associated minerals of Meiduk's. In contrast, the Tongling mine features minerals such as quartz, anatase, barite, sodium feldspar, illite, and malachite.Through EPMA and LA-ICP-MS results, the turquoises of Tongling exhibit similar average iron content(1.28% and 1.26% respectively), but significant differences in copper content. The turquoises of Meiduk have the average copper content of 6.97%, whereas Tongling samples show the higher content of 11.38%. Na, K, and Ca concentrations are also higher in Meiduk samples, suggesting interaction with alkali-rich fluids and potassic alteration. Trace elements such as Ti, Cr, Zn, Se, and Mo serve as tracing agents for Meiduk samples, while Be and W are associated with Tongling samples. Regarding rare earth elements(REEs), Meiduk samples show diverse δCe(0.14-4.62) and δEu(0.65-15.78) values, indicating a wide range of oxidation states and europium anomalies. The significant variability in LREE/HREE ratios(0.39-31.74) and ΣREE concentrations(0.25-240.72 ppm) suggests heterogeneous REE fractionation patterns. In contrast, Tongling samples display δCe(0.070-2.51) and δEu(0.238-4.87) ranges, with more consistent LREE/HREE ratios(0.128-10.2) and ΣREE values(0.069-4.08 ppm), indicating stable REE fractionation dynamics.This comparative study of turquoises from the Meiduk mine in Iran and the Tongling mine in China reveals significant similarities and differences in their geochemical and mineralogical characteristics. Both deposits are hosted within magmatic rocks and produce turquoise as a byproduct in open-pit copper mining operations, exhibiting comparable colors, patterns, and morphologies. However, distinct differences are noted in their mineral compositions and trace elements, with turquoise from Meiduk associated with a complex hydrothermal system rich in various sulfide and oxide minerals and higher copper, Na, K, and Ca concentrations, indicating alkali-rich fluid interactions. In contrast, the turquoise from Tongling, influenced by both volcanic and sedimentary processes, shows a higher copper content, presence of barite, and different trace elements such as Be and W. The REE patterns also highlight the contrasting geological histories and environmental conditions at each site, with Meiduk samples showing a broader range of oxidation states and europium anomalies compared to the more stable REE fractionation dynamics in Tongling samples. These differences underscore the importance of detailed geochemical and mineralogical analyses for accurate provenance determination in gemmological and archaeological contexts. 展开更多
关键词 TURQUOISE copper mine origin determination Meiduk iran Tongling China
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Heideggerian Thought in the Light of Iranian-Islamic Wisdom
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作者 Bogdana Todorova 《Philosophy Study》 2024年第3期123-128,共6页
A prominent Iranian philosopher Ahmad Fardid considered the influential German philosopher Martin Heidegger as“the only Western philosopher who understood the world and the only philosopher whose insights were congru... A prominent Iranian philosopher Ahmad Fardid considered the influential German philosopher Martin Heidegger as“the only Western philosopher who understood the world and the only philosopher whose insights were congruent with the principles of the Islamic Republic”.The report aimed to present Fardid’s interpretation of Heidegger in the light of Iranian-Islamic wisdom.Iranian philosopher believes that Heidegger’s thought responds to the most important intellectual crisis of the West civilization that is nihilism and to reach the possibility of an“other beginning”of thinking that he calls“No-longer-metaphysical-thought”.Considering these two fundamental features,Fardid founds powerful religious-spiritual tendencies in Heidegger’s thinking. 展开更多
关键词 Heidegger iran Ahmad Fardid WISDOM
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The subfamily Panchaetothripinae(Thysanoptera:Thripidae) in Iran,with the first report of genus Selenothrips Karny 被引量:2
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作者 马吉德 陈学新 《Entomotaxonomia》 CSCD 北大核心 2012年第1期22-29,共8页
The subfamily Panchaetothripinae Bagnall is one of the 4 subfamilies in the family Thripidae. This subfamily includes 6 species in 5 genera in Iran. In this paper, the monobasic genus Selenothrips Kamy is recorded in ... The subfamily Panchaetothripinae Bagnall is one of the 4 subfamilies in the family Thripidae. This subfamily includes 6 species in 5 genera in Iran. In this paper, the monobasic genus Selenothrips Kamy is recorded in Iran for the first time. A key is provided for identifying these 6 genera with comments on each genus and its species. The geographical distribution is provided for 7 species occurring in Iran. 展开更多
关键词 THRIPIDAE Panchaetothripinae Selenothrips geographical distribution iran
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Geochemical and Nd-Sr Isotopic Compositions of Hypabyssal Adakites in the Torud-Ahmad Abad Magmatic Belt,Northern Central Iran Zone:Analysis of Petrogenesis and Geodynamic Implications 被引量:3
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作者 Fazilat Yousefi Ryan D.Mills +4 位作者 Mahmoud Sadeghian David R.Lentz Christina Wanhainen Habibollah Ghasemi Laicheng Miao 《Journal of Earth Science》 SCIE CAS CSCD 2021年第6期1428-1444,共17页
Eocene intermediate to felsic subvolcanic rocks of the Torud-Ahmad Abad magmatic belt(TAMB),in the northern part of the Central Iran zone,are exposed between the Torud and Ahmad Abad regions in South-Southeast Shahroo... Eocene intermediate to felsic subvolcanic rocks of the Torud-Ahmad Abad magmatic belt(TAMB),in the northern part of the Central Iran zone,are exposed between the Torud and Ahmad Abad regions in South-Southeast Shahrood.These igneous rocks include hypabyssal dacite,trachyte,andesite,trachy-andesite,and basaltic andesite;they are mainly composed of phenocrysts and microcrystalline groundmass of pyroxene,amphibole,and plagioclase,with minor biotite and titanomagnetite;they form domal structures(plugs and stocks),dikes,and sills that intruded into Neoproterozoic to cogenetic Eocene volcano-sedimentary sequences.Based on isotopic analysis of these intermediate to acidic rocks,initial ratios of^(143)Nd/^(144)Nd range from 0.512775 to 0.512893 and initial ratios of^(87)Sr/^(86)Sr range from 0.703746 to 0.705314,with quite positiveε_(Nd(i))values of+3.69 to+6.00.They are enriched in light rare earth elements and large ion lithophile elements and depleted in heavy rare earth elements and high-field strength elements,the SiO_(2) content is(52-62)wt.%,and Na_(2)O content>3 wt.%,Al_(2)O_(3) content>16 wt.%,Yb<1.8 ppm,and Y<18 ppm.These geological,geochemical,and Sr and Nd isotopic data are consistent with adakitic signatures originating by partial melting of the subducted Neo-Tethys oceanic slab(Sabzevar branch)and lithospheric suprasubduction zone mantle.The mantle signatures typifying the rapidly emplaced adakitic rocks(slab(high-silica adakite)and suprasubduction zone(low-silica adakite)melts)together with their locally voluminous extent are evidences that support a locally extensional geodynamic setting;and the evidence is consistent with an evolution to local transpression in the Late Eocene in this convergent margin are environment to rifting(basalts to adakites)towards submarine conditions in the Neogene. 展开更多
关键词 isotope geochemistry adakite rocks Central iran zone Shahrood iran
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基于IRBFNN和IRAN的非线性动态系统在线自适应建模
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作者 刘士荣 俞其江 +1 位作者 李文磊 俞金寿 《华东理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2006年第7期784-788,共5页
将资源分配网络算法(RAN)与相似隐单元合并操作、冗余隐单元删除操作和基于滑动数据窗连接权值学习相结合,形成了改进的资源分配网络(IRAN)算法。IRAN算法用于非线性动态系统的在线建模,能有效地改善模型精度和泛化能力。将改进径向基函... 将资源分配网络算法(RAN)与相似隐单元合并操作、冗余隐单元删除操作和基于滑动数据窗连接权值学习相结合,形成了改进的资源分配网络(IRAN)算法。IRAN算法用于非线性动态系统的在线建模,能有效地改善模型精度和泛化能力。将改进径向基函数(RBF)神经网络(IRBFNN)和IRAN结合可以用于不确定非线性动态系统自适应建模。仿真研究表明:所提出的建模方法在模型精简、泛化和自适应等方面均具有优良的性能。 展开更多
关键词 非对称高斯函数 iran算法 非线性动态系统 在线自适应建模
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The Thrips-attacking Genus Ceranisus (Hymenoptera:Eulophidae:Entedoninae) from Iran
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作者 谭江丽 马吉德 +1 位作者 何俊华 陈学新 《Entomotaxonomia》 CSCD 北大核心 2010年第1期62-68,共7页
Three thrips-attacking parasitoids,Ceranisus menes(Walker,1839),C.planitianus Erds,1966 and C.amanosus Doganlar et al.,2009,are recorded from Iran for the first time.This also represents the first record of the genu... Three thrips-attacking parasitoids,Ceranisus menes(Walker,1839),C.planitianus Erds,1966 and C.amanosus Doganlar et al.,2009,are recorded from Iran for the first time.This also represents the first record of the genus Ceranisus Walker,1841 for Iran.Identification of the two sibling species,C.amanosus Doganlar et al.,2009 and C.udnamtak Tryapitsin,2005,is briefly discussed. 展开更多
关键词 HYMENOPTERA CHALCIDOIDEA EULOPHIDAE new record PARASITOIDS iran
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Notes on Eight Species of Encyrtidae (Hymenoptera: Chalcidoidea) from Iran with a Description of one New Species
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作者 徐志宏 H.Lotfalizadeh 《Entomotaxonomia》 CSCD 2000年第1期61-64,共4页
The paper reports 8 species of 7 genera of Encyrtidae, i. e. Anagyrus pseudococci, Cheiloneurus ceroplastis, Dusmetia fascipennis, Homalotylus ephippium associated with scale insects on trees, Isodromus atriventris... The paper reports 8 species of 7 genera of Encyrtidae, i. e. Anagyrus pseudococci, Cheiloneurus ceroplastis, Dusmetia fascipennis, Homalotylus ephippium associated with scale insects on trees, Isodromus atriventris, Isodromus collimaculatus sp. nov., Ooencyrtus kuvanae associated with lacewing insects, and Syrphophagus aeruginosus , a parasitoid of Syrphids. All specimens are deposited in the Department of Plant Protection, Zhejiang University, Hangzhou, China. 展开更多
关键词 HYMENOPTERA tree pests scale insects PARASITOIDS ENCYRTIDAE iran
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Relationship Between Land Use Changes and the Production of Dust Sources in Kermanshah Province,Iran
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作者 AHMADI-MOLAVERDI Majid JABBARI Iraj FATHNIA Amanollah 《Chinese Geographical Science》 SCIE CSCD 2021年第6期1057-1069,共13页
Recognizing land use changes(LUC)and evaluating their relationship with producing dust sources are considered effective to manage the environment.Taking Kermanshah Province,Iran as study area,dusty days from 2008 to 2... Recognizing land use changes(LUC)and evaluating their relationship with producing dust sources are considered effective to manage the environment.Taking Kermanshah Province,Iran as study area,dusty days from 2008 to 2015 were selected and dust sources were identified applying thermal-infrared dust index(TDI),hybrid single-particle lagrangian integrated trajectory(HYSPLIT),false color composite(FCC)and true color composite(TCC)of MODerate resolution Imaging Spectroradiometer(MODIS)images.Afterwards,the land use change map was produced using Landsat images in 2000 and 2015.Then,the distribution and frequency of the sources in each land-use change class and important dust production areas were specified.Eventually,two non-parametric tests including Chisquare and Kruskal-Wallis were applied to examine the relationship between LUC and dust sources.Results indicated that the distribution of dust sources was not identical in the study area,and the sources were mainly generated in the areas where land-use change had occurred.In fact,different classes of LUC have different contributions to dust production,and the highest contribution refers to the deflation in gentle slope areas and lowlands where the rangeland has been converted into agriculture land.The findings from this study are useful to manage and control dust in the identified sources. 展开更多
关键词 dust source hybrid single-particle lagrangian integrated trajectory(HYSPLIT) land use change(LUC) MODerate resolution imaging spectroradiometer(MODIS) thermal-infrared dust index(TDI) Kermanshah Province iran iran
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