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Characterization of six tumorsuppressor genes and microsatellite instability in hepatocellular carcinomain southern African blacks 被引量:21
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作者 Martins C Kedda MA Kew MC 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第6期470-476,共7页
AIM To analyse cumulative loss of heterozygosity (LOH) of chromosomal regions and tumor suppressor genes in hepatocellular carcinomas (HCCs) from 20 southern African blacks. METHODS p53, RB1, BRCA1, BRCA2, WT1 and E c... AIM To analyse cumulative loss of heterozygosity (LOH) of chromosomal regions and tumor suppressor genes in hepatocellular carcinomas (HCCs) from 20 southern African blacks. METHODS p53, RB1, BRCA1, BRCA2, WT1 and E cadherin genes were analysed for LOH, and p53 gene was also analysed for the codon 249 mutation, in tumor and adjacent non tumorous liver tissues using molecular techniques and 10 polymorphic microsatellite markers. RESULTS p53 codon 249 mutation was found in 25% of the subjects, as was expected, because many patients were from Mozambique, a country with high aflatoxin B 1 exposure. LOH was found at the RB1, BRCA2 and WT1 loci in 20%(4/*!20) of the HCCs, supporting a possible role of these genes in HCC. No LOH was evident in any of the remaining genes. Reports of mutations of p53 and RB1 genes in combination, described in other populations, were not confirmed in this study. Change in microsatellite repeat number was noted at 9/*!10 microsatellite loci in different HCCs, and changes at two or more loci were detected in 15%(3/*!20) of subjects. CONCLUSION We propose that microsatellite/genomic instability may play a role in the pathogenesis of a subset of HCCs in black Africans. 展开更多
关键词 carcinoma hepatocellular southern African blacks CUMULATIVE LOH TUMOR SUPPRESSOR genes MICROSATELLITE genomic instability liver neoplasms
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Trends of Cardiovascular Mortality in Blacks Africans from Central African City: Hospital Based Study, Brazzaville (Congo)
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作者 Bertrand F. Ellenga-Mbolla Aude Loko-Lemba +5 位作者 Solange F. Mongo-Ngamami Christian M. Kouala-Landa Igor Ondze-Kafata Stephane M. Ikama Thierry R. Gombet Gisèle Kimbally-Kaky 《World Journal of Cardiovascular Diseases》 2019年第9期698-705,共8页
Background: To determine mortality causes and the associated factors. Patients and Method: This cross-sectional study was conducted from June 2014 to May 2015 (1 year) in the department of cardiology at University and... Background: To determine mortality causes and the associated factors. Patients and Method: This cross-sectional study was conducted from June 2014 to May 2015 (1 year) in the department of cardiology at University and teaching Hospital of Brazzaville. Patients admitted for cardiovascular diseases were included. Patients admitted for cardiovascular disease in other departments of the hospital, or without cardiovascular diseases were not included. Results: In total, 1035 patients, 605 women (5804%) were included. Mean age was 57.1 ± 7 years (range: 18 - 85 years). The patients were: elderly (n = 498, 48.1%), educated (n = 809, 78.1%), low-income (n = 253, 24.2%). The medical history of patients was: hypertension (n = 440, 42.5%), diabetes (n = 316, 30.5%), reduced physical activity (n = 154, 14.9%), excessive alcohol intake (n = 56, 5.4%). Heart failure was reported in 386 cases (37.3%). The mortality rate was 8% (n = 83);the mean age of deceased was 61.9 ± 7.3 years (p s in death were dilated cardiomyopathy (n = 37, 44.6%, OR 5, 95%CI 3.1 - 8, p -3.3, p = 0.002), atrial fibrillation (n = 24, 29%, OR 3.6, 95%CI 2.2 - 6, p - 9.8, p = 0.005). The associated death comorbidities were: acute respiratory infection (n = 44, 53%, OR 10.1, 95%CI 6.2 - 16, p - 10 p - 6.8, p Conclusion: Hypertension, heart failure and cardiomyopathies are the leading causes of mortality in the department of cardiology. Prevention and patient education in a low-income environment are essential elements to reduce this morbidity. 展开更多
关键词 Mortality CARDIOVASCULAR Disease blacks AFRICANS Sub-Saharan AFRICA
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Fibroadenoma in Blacks
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作者 Raphael Odobueze Egejuru Ikechukwu Godfrey Nnadi Okechukwu Nwabugo Duru 《Health》 2017年第11期1475-1481,共7页
Background: Fibroadenoma is the commonest benign tumour of the breast affecting the majority of young females below the age of thirty in our environment. It is a source of concern and psychological problems in females... Background: Fibroadenoma is the commonest benign tumour of the breast affecting the majority of young females below the age of thirty in our environment. It is a source of concern and psychological problems in females requiring medical attention in our hospitals. Aim: This study describes the clinicopathologic characteristics of fibroadenoma in Eastern Nigerian Igbo females. Methodology: The archives of the Department of Pathology Federal Medical Centre, Owerri was used for the data collection and analyzed using simple statistics. Results: 504 fibroadenomas were analyzed. The average size was 1.99 cm with a range of 0.5 cm to 18 cm. The average age of the patients was 22.6 ± 6.7 years with a range of 9 to 60 years. The peak age of incidence was in the 11 - 20 (44.64%) age group followed closely by the 21 - 30 (43.45%) age group. The ratio of involvement of the left to the right breast was 1:1.2. Fibroadenoma was 18% multiple and 10.7% bilateral. 5.3% (27), 0.6% (3), and 0.2% (1) of the cases were giant, complex fibroadenoma and malignant breast disease in fibroadenoma respectively. Conclusion: This study has provided insights into the clinicopathologic characteristics of fibroadenoma among Nigerian Igbos and calls for more research in this area in other parts Nigeria and elsewhere. 展开更多
关键词 FIBROADENOMA blacks Owerri
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“Not Now!”1—On the Contemporary Relevance of Faulkner's Exploration of the Blacks
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作者 BAO Zhong-ming XIN Cai-na 《Journal of Literature and Art Studies》 2015年第5期346-354,共9页
The accession of an African-American Obama to the U.S. Presidency in 2008 is an epoch-making event. The thesis focuses on the current situation of the blacks in U.S. to highlight the prophetic nature of Faulkner, the ... The accession of an African-American Obama to the U.S. Presidency in 2008 is an epoch-making event. The thesis focuses on the current situation of the blacks in U.S. to highlight the prophetic nature of Faulkner, the Nobel Prize winning American novelist's exploration of the blacks throughout his career, namely, the miserable living states of the blacks, racial segregation against the blacks in the sphere of education and religion, racial discrimination against the blacks with regard to civil rights, racial persecution against the blacks in legal cases, and the dependency upon the black leadership to salvage the multi-ethnic nation and so on. The paper comes up with the conclusion that Faulkner is accurate in his prophecy that the savior of the nation, the blacks shall suffer and lead. 展开更多
关键词 William Faulkner Barrack Obama race the blacks human rights
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HNA-1 a and HNA-1 b gene frequencies in the Tunisian Blacks
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《中国输血杂志》 CAS CSCD 2001年第S1期366-,共1页
关键词 HNA-1 a and HNA-1 b gene frequencies in the Tunisian blacks GENE
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The Tragedy of Jeff and the Rising of American Blacks Today
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作者 Xia Xiaobin 《福建江夏学院学报》 1995年第2期42-44,共3页
"Nigger Jeff"is a short story,It was written by Theodore Dreiser,a famous American novel-ist in the twentieth century. It was no accident that such a work snould appear during the era of racial discrimanatio... "Nigger Jeff"is a short story,It was written by Theodore Dreiser,a famous American novel-ist in the twentieth century. It was no accident that such a work snould appear during the era of racial discrimanation.The setting of the story is the South. The balcks were slaves before the Civil War there. They re-mained the second class citizens after. Southern whites often used lynching without trial to pur-nish imdividuals and intimeidate the balcks in general. In this story,Jeff,a typical of all the 展开更多
关键词 In The Tragedy of Jeff and the Rising of American blacks Today
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Hepatocellular carcinoma in African Blacks: Recent progress in etiology and pathogenesis 被引量:5
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作者 Michael C Kew 《World Journal of Hepatology》 2010年第2期65-73,共9页
Occult hepatitis B virus (HBV) infection was shown to be present in 75% of Black Africans with hepatocellular carcinoma (HCC) in whom the tumor was hitherto not thought to be caused by chronic HBV infection. The assoc... Occult hepatitis B virus (HBV) infection was shown to be present in 75% of Black Africans with hepatocellular carcinoma (HCC) in whom the tumor was hitherto not thought to be caused by chronic HBV infection. The association between chronic HBV infection and the development of the tumor is thus even closer than was originally thought. HBV viral load was found to be significantly higher in patients with HCC than in Black African controls. As in other populations, HBV e antigen-positive patients with hepatocellular carcinoma had significantly higher viral loads than patients negative for this antigen. The significance of this finding is discussed. The risk for HCC development with genotype A of HBV, the predominant genotype in African isolates, has not been investigated. Genotype A was shown to be 4.5 times more likely than other genotypes to cause HCC in Black Africans, and tumours occurred at a significantly younger age. Increasing numbers of patients with human immunodeficiency virus (HIV) and HBV co-infection are being reported to develop HCC. A preliminary case/control comparison supports the belief that HIV co-infection enhances the hepatocarcinogenic potential of HBV. A study from The Gambia provides the first evidence that dietary exposure to afltoxin B1 may cause cirrhosis and thatthis may play a contributory role in the pathogenesis of aflatoxin-induced HCC. An animal model has provided experimental support for the clinical evidence that dietary iron overload in the African is directly hepatocarcinogenic, in addition to causing the tumor indirectly through the development of cirrhosis. 展开更多
关键词 Hepatocellular carcinoma Black Africans Occult hepatitis B Virus infection Hepatitis B viral loads Hepatitis B virus genotype A AFLATOXIN Dietary iron overload
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Relationship between Obesity, Serum Uric Acid, Serum Potassium and Glomerular Filtration Rate with Electric Left Ventricular Hypertrophy in Blacks Central Africans with High Blood Pressure 被引量:1
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作者 Bertrand Fikahem Ellenga Mbolla Paul Macaire Ossou Nguiet +6 位作者 Richard Loumingou Meo Stéphane Ikama Narcisse Ngangoue Thierry Raoul Gombet Henri Germain Monabeka Benjamn Longo Mbenza Gisèle Kimbally Kaky 《World Journal of Cardiovascular Diseases》 2018年第4期248-255,共8页
The authors conducted a retrospective study over a period of 6 months in a hypertensive population in order to determine the correlation between serum uric acid on glomerular filtration rate (GFR) and estimated serum ... The authors conducted a retrospective study over a period of 6 months in a hypertensive population in order to determine the correlation between serum uric acid on glomerular filtration rate (GFR) and estimated serum potassium with left ventricular hypertrophy (LVH) and obesity. This study enrolled 122 patients including 63 women (51.6%). The mean age was 55.9 ± 10.6 years (range 30 to 74 years). Obesity weight was found in 38 cases (31.1%) of which 20?were men (33.9%) and 18 women (28.6%). Abdominal obesity was found in 104 cases (85.2%). The average serum uric acid in patients with obesity weight was 63.3 ± 18.9 mg/L vs 62.4 ± 14.2 mg/L for no-obese patients (p?= 0.63). The average serum potassium in obese patients was 4.06 ± 0.42 mEq/L vs 4.02 ± 0.46 mEq/L for no-obese (p?= 0.65). The average GFR was 73.4 ± 21.4 ml/L in obese patients vs 66.6 ± 22.6 ml/min in no-obese (p?= 0.03). The LVH was found in 81 cases (66.4%). The LVH was found in 65 (62.5%) obese patients vs?16 (88%) non-obese patients (OR = 4.8, 95% 1.04?-?22?p?= 0.02). Only abdominal?obesity has been correlated with left ventricular hypertrophy after multivariate analysis. Emphasis must be focused on public health actions for effective and appropriate measures against obesity and hypertension, whose prevalence is increasing in our region. 展开更多
关键词 OBESITY High Blood Pressure Glomerular FILTRATION Rate Uric Acid SERUM POTASSIUM Black AFRICAN
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Effects of cerium oxide doping on performance characteristics of nickel-based black coatings
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作者 QIN Zizhou CHEN Liyang +5 位作者 YANG Yumeng MAO Xifeng ZHU Benfeng GUO Weirong WEI Guoying ZHANG Luhan 《电镀与精饰》 北大核心 2026年第1期25-38,共14页
Black nickel coatings have emerged as a research hotspot in materials science due to their excellent performance and broad application prospects.In this study,nickel-based black coatings were fabricated on low-carbon ... Black nickel coatings have emerged as a research hotspot in materials science due to their excellent performance and broad application prospects.In this study,nickel-based black coatings were fabricated on low-carbon steel substrates via photo-assisted electrodeposition.A systematic investigation was conducted on the effects of cerium ion concentration and nano-ceria(CeO_(2))particle content in the electrolyte on the coating properties,along with an analysis of the temporal evolution of coating’s corrosion resistance.When the cerium ion concentration in the electrolyte was 0.05 mol/L,the coating exhibited a uniform black appearance with a light absorption rate of 95%,an emissivity of 0.87,maximum impedance,and the lowest corrosion tendency,demonstrating optimal comprehensive performance.The coating prepared with a nano-ceria concentration of 6 g/L in the electrolyte exhibited an emissivity of 0.9,achieved a 5B adhesion grade(ASTM D3359-09),and demonstrated a one-order-of-magnitude reduction in corrosion current density compared to coatings fabricated without nano-ceria in the electrolyte.With prolonged storage time,the coating's impedance slightly increased,leading to improved corrosion resistance. 展开更多
关键词 nickel-based coatings black coatings Ce oxide protective properties
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Turning Black Waste into a Green Resource
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作者 LIU JING 《China Today》 2026年第1期68-70,共3页
To deal with a polluted by-product of coal production,central China’s Shanxi Province has explored a governance path that addresses both the symptoms and root causes.
关键词 black waste green resource polluted product shanxi province coal production governance path
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Plucking Heartstrings--Young musicians bring ancient instruments into the modern era
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作者 Li Xiaoyang 《Beijing Review》 2026年第3期38-39,共2页
Chinese video game Black Myth:Wukong has been a hit among gaming enthusiasts world-wide since its release in 2024,its breakout success demonstrating the potential global appeal of traditional Chinese culture.Based on ... Chinese video game Black Myth:Wukong has been a hit among gaming enthusiasts world-wide since its release in 2024,its breakout success demonstrating the potential global appeal of traditional Chinese culture.Based on 16th-century classic novel Journey to the West,the game is not only introducing international audiences to Chinese literature,but has also become a far-reaching platform for traditional Chinese music. 展开更多
关键词 Black Myth Wukong traditional Chinese culture traditional chinese music ancient instruments modern era plucking heartstrings global appeal Chinese video game
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Morality and Realpolitik:The Ideas of American Upper Class in the North on the Blacks and Slavery Before the Civil War
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作者 Gao Yue 《World History Studies》 2022年第2期35-55,共21页
The condemnations of black slavery were not common before the mid-18th century,and they were mostly based on Christian egalitarianism.Around the American Revolution,with the spread of the theory of natural rights,many... The condemnations of black slavery were not common before the mid-18th century,and they were mostly based on Christian egalitarianism.Around the American Revolution,with the spread of the theory of natural rights,many social elites believed that slavery deprived blacks of their natural rights and violated the principle of equality in a democratic republic.Anti-slavery gradually became the mainstream public opinion.However,since slaves were private property of many politicians,the abolition of slavery would act against the interests of white elites,and the ideology of racial confrontation between blacks and whites provided an identity to the white community.Therefore,slavery was reserved from the founding period.In the mid-19th century,various social reforms arose.Humanitarianism was deeply rooted in elites'minds,and the idea that blacks have the general attributes of human beings is gradually accepted by educated white people.The sense of dignity of work in the North constituted a different value from the South and became another theoretical basis for public voice to criticize slavery.However,for the sake of party unity and the national interest,the abolition were not put into practice until the Civil War broke out.By the middle of the 19th century,although the public opinion of anti-slavery was formed in the North,the upper class elites held the position of realpolitik while balancing the morality of abolition and the economic and political interests. 展开更多
关键词 blacks SLAVERY Upper Class in the North Natural Right HUMANITARIANISM
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To What Extent Does Racial Discrimination Affect Blacks Working in the United States?
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作者 Che Chen 《Advances in Social Behavior Research》 2024年第6期16-24,共9页
This study provides an in-depth discussion of the effects of racial discrimination in the United States on blacks when it comes to job searching and job advancement.Compared to Whites,blacks are inlcined to be more sa... This study provides an in-depth discussion of the effects of racial discrimination in the United States on blacks when it comes to job searching and job advancement.Compared to Whites,blacks are inlcined to be more satisfied with their employment,but they have more difficulty finding jobs,and most of them are inclined to be in lower level jobs and slow to advance.Racial discrimination affects society in many ways.White racists can have a large impact on blacks so it is crucial to understand this impact.Previously,racial discrimination in the U.S.would have a large impact on the daily lives(work,participation in activities,range of socialization,living,living environment)of blacks-who generally clustered in a certain neighborhood with a crowded environment.Now,although this phenomenon has improved since the issuance of the Emancipation Proclamation in 1862,it’s still prevalent and there have been few changes.For this reason this essay investigates the extent to which racial discrimination affects black jobs in the United States and calls for more attention to racial discrimination and equal treatment of each race. 展开更多
关键词 racial discrimination blacks working African Americans
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VIIRS夜光影像中农田火像素识别方法
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作者 曹汉瑞 王妍 +3 位作者 李熙 胡申森 邱实 魏英策 《武汉大学学报(信息科学版)》 北大核心 2025年第10期2072-2085,共14页
夜光遥感影像已被广泛应用于人类活动、社会经济等方面的研究。南部非洲的夜光影像上存在烧田产生的农田火像素,这些像素易与城镇灯光像素混淆,干扰了夜光影像在社会经济评估中的应用。以南部非洲的10个大陆国家为研究区域,基于国家极... 夜光遥感影像已被广泛应用于人类活动、社会经济等方面的研究。南部非洲的夜光影像上存在烧田产生的农田火像素,这些像素易与城镇灯光像素混淆,干扰了夜光影像在社会经济评估中的应用。以南部非洲的10个大陆国家为研究区域,基于国家极地轨道伙伴关系卫星(national polar-orbiting partnership,NPP)/可见光红外成像辐射仪(visible infrared imaging radiometer,VIIRS)数据生产的黑色大理石(Black Marble)产品,首先构建了夜光辐亮度时间序列的3个特征;然后采用随机森林分类方法将夜光影像中的像素分为农田火像素、稳定灯光像素和全黑像素;最后采用分层随机抽样,用时间序列夜光辐亮度数据、高分辨率卫星影像和地表覆盖数据对像素分类结果进行精度检验。结果表明,像素分类的总体精度为91.2%,平均生产者精度为91.9%,平均用户精度为91.0%,其中农田火像素分类的生产者精度和用户精度分别为86.4%和92.6%。所提方法可在后续应用中滤除Black Marble产品中的农田火像素,提升夜光影像对非洲社会经济的评估精度。 展开更多
关键词 夜光遥感 NPP/VIIRS Black Marble产品 南部非洲 农田火
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Designing sandwich-structured IBP nanosheets with superior antioxidant property to enhance corrosion resistance,flame retardancy,and wear resistance for polymeric coatings 被引量:1
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作者 Qihan Weng Li Zhang +1 位作者 Xinxin Sheng Delong Xie 《Journal of Materials Science & Technology》 2025年第12期22-35,共14页
The rapid development of industrialization requires the advancement of multifunctional coatings.In this study,successful self-assembly of iron porphyrin on BP nanosheets resulted in the synthesis of IBP nanosheets wit... The rapid development of industrialization requires the advancement of multifunctional coatings.In this study,successful self-assembly of iron porphyrin on BP nanosheets resulted in the synthesis of IBP nanosheets with a sandwich structure.Characterization tests including SEM,XPS,SPM,and XRD confirmed the successful preparation of IBP nanosheets with robust structural stability and antioxidation.Subsequently,a water-based epoxy resin(WEP)coating containing IBP nanosheets was prepared.Test results revealed that the composite coating containing 0.4 wt.%IBP nanosheets exhibited outstanding anti-corrosion,wear-resistant,and flame-retardant properties.After 42 days of immersion in a 3.5 wt.%NaCl solution,the Rct value of the 4-IBP/WEP coating was 1.79×10^(9)Ωcm^(2),surpassing the Pure WEP coating by more than 3 orders of magnitude.Additionally,the peak heat release rate(PHRR)and wear rate of the 4-IBP/WEP coating decreased by 19.29%and 90.97%compared to the Pure WEP coating.This research presents a novel idea for the utilization of BP nanosheets in multifunctional coatings. 展开更多
关键词 Black phosphorus Corrosion resistance WEAR-RESISTANT FLAME-RETARDANT
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Weathering Process of Parent Material and Accumulation Process of Organic Carbon on the Black Soil Profile:A Case Study from the Keshan Area of the Songnen Plain in Northeast China 被引量:1
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作者 XIA Rui YUAN Guoli +5 位作者 CUI Minli HOU Hongxing YU Guangming GE Liangsheng LU Kaining REN Bingzhang 《Acta Geologica Sinica(English Edition)》 2025年第1期258-271,共14页
Black soil is essential for maintaining regional food security and promoting global agricultural production.Understanding the weathering process of parent material and the accumulation of organic carbon is crucial to ... Black soil is essential for maintaining regional food security and promoting global agricultural production.Understanding the weathering process of parent material and the accumulation of organic carbon is crucial to comprehending the developmental history and future trends of black soil,especially against the background of large-scale global cultivation and climate change.Although the importance of black soil formation and evolution cannot be ignored,the relevant research is still very scarce.In this study,a typical eight-meter-deep soil core was collected from the Keshan area of the Songnen Plain,Northeast China,where surface black soil developed on paleo-sediments.Using^(14)C dating,the formation age of the black soil was determined.Based on the characteristics of the geochemical composition,grain size and the magnetic susceptibility of the sediments,it was demonstrated that the black soil and its parent material originated from reworked loess.Furthermore,the mass transfer coefficient(τ)of some elements was determined,in order to explore the soil weathering process.By calculating the transported amount of alkaline and alkaline-earth elements,the weathering rate of parent material to black soil was found to be weak,at 0.16 kEq·ha^(-1)·year^(-1).Combining the results of dating and carbon density in the different layers of black soil,the accumulation rate of organic carbon was determined as follows:rapidly increasing in the initial period of 13.2-2.2 ka,reaching its maximum average value of 34.0 g·cm^(-2)·a^(-1)at 2.2-0.8 ka,then showing a decreasing trend with an average value of-77.5 g·cm^(-2)·a^(-1).Compared with regional climate change,Keshan black soil has developed under a colder and wetter climate during the Holocene.Predictably,ongoing global warming may lead to the degradation of black soils in the Songnen Plain,as well as in other regions.Our results will enrich geological knowledge of black soil formation and future evolutionary trends. 展开更多
关键词 black soil PROVENANCE weathering rate organic carbon accumulation rate Songnen Plain
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Newly Identified Au-Ag-Bi-Te Mineralization in the Aydindere Skarn Fe and Cu Deposit,Giresun,NE Turkey:Implications of Gold Mineralization during Retrograde Skarn Evolution 被引量:1
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作者 Ahmet Sasmaz Vitaliy Sukach +7 位作者 Serhiy Bondarenko Hryhorii Aleksiienko Hengameh Erfanian Kaseb Bilge Sasmaz Sergiy Kurylo Oleksandr Hrinchenko Volodymyr Somka Panagiotis Voudouris 《Journal of Earth Science》 2025年第2期543-561,共19页
This study investigates the mineralogy and mineral-chemistry of a newly discovered Au-Ag-Bi-Te mineralization at the Aydindere Fe-Cu skarn deposit,within the Pontides Tectonic Unit,northeastern Turkey.The mineralizati... This study investigates the mineralogy and mineral-chemistry of a newly discovered Au-Ag-Bi-Te mineralization at the Aydindere Fe-Cu skarn deposit,within the Pontides Tectonic Unit,northeastern Turkey.The mineralization is developed in the skarn zone at the contact between Upper Cretaceous andesite-pyroclastic rocks and a Paleocene–Eocene I-type granitoid.The principal ore minerals of the Aydindere Fe-Cu deposit are oxides(magnetite),sulfides(pyrite-chalcopyritegalena-sphalerite),tellurides/sulfotellurides(tetradymite,hessite),sulfosalts(wittichenite,emplectite,aikinite) and native gold-electrum.Skarn minerals include anhydrous phases(garnet) formed in a prograde stage and hydrous phases(amphibole,epidote,chlorite),which were formed in a retrograde stage in association with quartz,adularia,apatite and late calcite.Sulfides,tellurides and sulfosalts are introduced during the retrograde stage.The Au-Ag-Bi-Te mineralization was detected for the first time within the western ore body of the Aydindere deposit,and occurs in calcite-bearing sulfide bodies that cut magnetite-garnet-amphibole-epidote skarns with magnetite ores of different grade,including massive magnetite.Chlorite geothermometry indicates formation of the Au-Ag-BiTe mineralization at temperatures between 300 and 250 ℃,during the retrograde skarn evolution.Assuming the temperature is ~275 ℃,logfS_(2) =-10.5 to-13,logfO_(2) =-37 to-33,and logf Te2 values range from approximately-12 to-8.5 were estimated.The available mineralogical and geological data(presences of magnetite,oxidized-type tellurides/sulfotellurides,and andraditic garnets,and absence of pyrrhotite and arsenopyrite) suggest that Aydindere is an oxidized Au-bearing skarn deposit.The discovery of Au-Ag-Bi-Te mineralization at Aydindere increases its productivity and requires more detailed exploration in the deposit for precious(Au,Ag) and critical(Bi,Te) metals. 展开更多
关键词 aydindere Black Sea Region telluredes oxidized gold-bearing skarn deposit mineral geology
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A Comprehensive Review of Natural Rubber Composites:Properties,Compounding Aspects,and Renewable Practices with Natural Fibre Reinforcement 被引量:1
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作者 Mohamad Firdaus Omar Fathilah Ali +6 位作者 Mohammed Saedi Jami Azlin Suhaida Azmi Farah Ahmad Mohd Zahid Marzuki Shantha Kumari Muniyandi Zuraidah Zainudin Minsoo P.Kim 《Journal of Renewable Materials》 2025年第3期497-538,共42页
This review provides a comprehensive overview of natural rubber(NR)composites,focusing on their properties,compounding aspects,and renewable practices involving natural fibre reinforcement.The properties of NR are inf... This review provides a comprehensive overview of natural rubber(NR)composites,focusing on their properties,compounding aspects,and renewable practices involving natural fibre reinforcement.The properties of NR are influenced by the compounding process,which incorporates ingredients such as elastomers,vulcanizing agents,accelerators,activators,and fillers like carbon black and silica.While effective in enhancing properties,these fillers lack biodegradability,prompting the exploration of sustainable alternatives.The potential of natural fibres as renewable reinforcements in NR composites is thoroughly covered in this review,highlighting both their advan-tages,such as improved sustainability,and the challenges they present,such as compatibility with the rubber matrix.Surface treatment methods,including alkali and silane treatments,are also discussed as solutions to improve fibre-matrix adhesion and mitigate these challenges.Additionally,the review highlights the potential of oil palm empty fruit bunch(EFB)fibres as a natural fibre reinforcement.The abundance of EFB fibres and their alignment with sustainable practices make them promising substitutes for conventional fillers,contributing to valuable knowledge and supporting the broader move towards renewable reinforcement to improve sustain-ability without compromising the key properties of rubber composites. 展开更多
关键词 Natural rubber composites natural fibres RENEWABLE REINFORCEMENT VULCANIZATION FILLERS carbon black silica surface treatment sound absorption acoustics
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High-resolution Simulation Dataset of Hourly PM_(2.5)Chemical Composition in China(CAQRA-aerosol)from 2013 to 2020 被引量:1
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作者 Lei KONG Xiao TANG +14 位作者 Jiang ZHU Zifa WANG Bing LIU Yuanyuan ZHU Lili ZHU Duohong CHEN Ke HU Huangjian WU Qian WU Jin SHEN Yele SUN Zirui LIU Jinyuan XIN Dongsheng JI Mei ZHENG 《Advances in Atmospheric Sciences》 2025年第4期697-712,共16页
Scientific knowledge on the chemical compositions of fine particulate matter(PM_(2.5)) is essential for properly assessing its health and climate effects,and for decisionmakers to develop efficient mitigation strategi... Scientific knowledge on the chemical compositions of fine particulate matter(PM_(2.5)) is essential for properly assessing its health and climate effects,and for decisionmakers to develop efficient mitigation strategies.A high-resolution PM_(2.5) chemical composition dataset(CAQRA-aerosol)is developed in this study,which provides hourly maps of organic carbon,black carbon,ammonium,nitrate,and sulfate in China from 2013 to 2020 with a horizontal resolution of 15 km.This paper describes the method,access,and validation results of this dataset.It shows that CAQRA-aerosol has good consistency with observations and achieves higher or comparable accuracy with previous PM_(2.5) composition datasets.Based on CAQRA-aerosol,spatiotemporal changes of different PM_(2.5) compositions were investigated from a national viewpoint,which emphasizes different changes of nitrate from other compositions.The estimated annual rate of population-weighted concentrations of nitrate is 0.23μg m^(−3)yr^(−1) from 2015 to 2020,compared with−0.19 to−1.1μg m^(−3)yr^(−1) for other compositions.The whole dataset is freely available from the China Air Pollution Data Center(https://doi.org/10.12423/capdb_PKU.2023.DA). 展开更多
关键词 PM_(2.5)composition dataset black carbon organic carbon AMMONIUM NITRATE SULFATE
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GeP_(3)/Ketjen Black Composite:Preparation via Ball Milling and Performance as Anode Material for Sodium-ion Batteries
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作者 YANG Shuqi YANG Cunguo +2 位作者 NIU Huizhu SHI Weiyi SHU Kewei 《无机材料学报》 北大核心 2025年第3期329-336,I0010,I0011,共10页
Metal phosphides have been studied as prospective anode materials for sodium-ion batteries(SIBs)due to their higher specific capacity compared to other anode materials.However,rapid capacity decay and limited cycle li... Metal phosphides have been studied as prospective anode materials for sodium-ion batteries(SIBs)due to their higher specific capacity compared to other anode materials.However,rapid capacity decay and limited cycle life caused by volume expansion and low electrical conductivity of phosphides in SIBs remain still unsolved.To address these issues,GeP_(3) was first prepared by high-energy ball milling,and then Ketjen black(KB)was introduced to synthesize composite GeP_(3)/KB anode materials under controlled milling speed and time by a secondary ball milling process.During the ball milling process,GeP_(3) and KB form strong chemical bonds,resulting in a closely bonded composite.Consequently,the GeP_(3)/KB anodes was demonstrated excellent sodium storage performance,achieving a high reversible capacity of 933.41 mAh·g^(–1) at a current density of 0.05 A·g^(–1) for a special formula of GeP_(3)/KB-600-40 sample prepared at ball milling speed of 600 r/min for 40 h.Even at a high current density of 2 A·g^(–1) over 200 cycles,the capacity remains 314.52 mAh·g^(–1) with a retention rate of 66.6%.In conclusion,this work successfully prepares GeP_(3)/KB anode-carbon composite for electrodes by high-energy ball milling,which can restrict electrode volume expansion,enhance capacity,and improve cycle stability of SIBs. 展开更多
关键词 sodium-ion battery GeP_(3)/C composite Ketjen black ball milling
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