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Sugar-sensing swodkoreceptors and swodkocrine signaling
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作者 Savani Anbalagan 《Animal Models and Experimental Medicine》 2025年第5期944-961,共18页
Sugars are one of the major metabolites and are essential for nucleic acid synthesis and energy production.In addition,sugars can act as signaling molecules.To study sugar signaling at the systemic level,there is an u... Sugars are one of the major metabolites and are essential for nucleic acid synthesis and energy production.In addition,sugars can act as signaling molecules.To study sugar signaling at the systemic level,there is an urgent need to systematically identify sugar-sensing proteins and nucleic acids.I propose the terms“swodkoreceptor”and“swodkocrine signaling,”derived from the Polish word“slodki”meaning“sweet,”to comprise all sugar-sensing proteins and signaling events,respectively,regardless of their cellular location and signaling domains.This proposal is intended to facilitate the inclusion of proteins such as the Escherichia coli Lac I repressor as an allolactose receptor,human glucokinase regulatory protein(GCKR)as a fructose receptor,and other sugar-binding based allosterically regulated enzymes and transcription factors as sugar-sensing receptors.In addition,enzyme-interacting proteins whose interaction state is regulated by sugar binding have also been proposed as sugar receptors.The systemic study of protein-and nucleic-acid-based swodkoreceptors may help to identify organelle-specific swodkoreceptors and to also address receptor duality.The study of intra-and inter-organism swodkocrine signaling and its crosstalk with gasocrine signaling may help to understand the etiology of diseases due to dysregulation in sugar homeostasis and signaling. 展开更多
关键词 CHEMORECEPTOR glucose sensor glucose receptor GLUCOKINASE glucokinase regulatory protein(GKRP) PROTOCELL protoorganelle protoreceptor receptor duality receptor multimodality riboceptor ribozyme sugar receptor sugar sensor taste receptor enzyme receptor duality
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Examples and effects of avalanches on the surface of mountain lakes:Morskie Oko,a case study from Poland(Tatra Mountains)
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作者 Adam CHOIŃSKI Wojciech DENEGA +1 位作者 Andrzej MACIAS Witold PINIARSKI 《Journal of Mountain Science》 2025年第2期375-390,共16页
This study represents a pioneering effort to analyze the impact of avalanches descending into Morskie Oko from Marchwiczny Gully,the most active avalanche path around the lake.It focuses on catastrophic avalanches tha... This study represents a pioneering effort to analyze the impact of avalanches descending into Morskie Oko from Marchwiczny Gully,the most active avalanche path around the lake.It focuses on catastrophic avalanches that descended from the analyzed gully,as reported in the literature from the 1900s until now.However,only the data collected in recent years,our field studies,combined with modern LIDAR data and GIS-based modeling,allowed us to perform a detailed analysis.The GIS-based approach effectively uses spatial data to address snow avalanche modeling challenges.Although the study area lies within Tatra National Park,no official services carry out systematic avalanche monitoring or measurements.The impact of hazardous events,such as snow avalanches,on the most famous Polish mountain lake,Morskie Oko,has been poorly described in the literature and has yet to be discovered.Therefore,to analyze the selected avalanche parameters,we mainly used our ground and additional aerial photographs taken by local mountain services and related field measurements.Our analysis resulted in figurative estimates of the extent and volume of avalanche snow and its weight,both on the surface of the ice sheet and the part of the avalanche that did not reach the lake's shore and remained on the slope of Marchwiczny Gully.For example,the values for the mighty avalanche on February 3,2023,are 23,500 m~3 and 4,700 tons on the ice surface and 20,000 m~3 and 4,000 tons on the slope.It was determined that avalanches that descend onto the studied lake's surface result in its shallowing.This process occurs because of sedimentation of slope material carried by avalanches,especially during the final phase of ice cover melting.When openings appear in the solid ice cover in spring,floating ice can migrate,driven by wind pressure,and deposit avalanche material in various parts of the lake bottom.Thus,avalanches contributed to the gradual disappearance of the lake. 展开更多
关键词 Snow avalanches Mountain lakes SEDIMENTATION Morskie Oko Tatra Mountains Avalanche modeling
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Pig meniscus single-cell sequencing reveals highly active red zone chondrocyte populations involved in stemness maintenance and vascularization development
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作者 Monika MANKOWSKA Monika STEFANSKA +6 位作者 Anna Maria MLECZKO Katarzyna SARAD Witold KOT Lukasz KRYCH Julia Anna SEMBA Eric Lars-Helge LINDBERG Jakub Dalibor RYBKA 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2025年第7期675-693,共19页
Meniscus injuries are widespread and the available treatments do not offer enough healing potential.Here,we provide critical support for using pigs as a biological model for meniscal degeneration and the development o... Meniscus injuries are widespread and the available treatments do not offer enough healing potential.Here,we provide critical support for using pigs as a biological model for meniscal degeneration and the development of cutting-edge therapies in orthopedics.We present a single-cell transcriptome atlas of the meniscus,consisting of cell clusters corresponding to four major cell types:chondrocytes,endothelial cells,smooth muscle cells,and immune cells.Five distinct chondrocyte subclusters(CH0–CH4)were annotated,of which only one was widespread in both the red and white zones,indicating a major difference in the cellular makeup of the zones.Subclusters distinct to the white zone appear responsible for cartilage-specific matrix deposition and protection against adverse microenvironmental factors,while those in the red zone exhibit characteristics of mesenchymal stem cells and are more likely to proliferate and migrate.Additionally,they induce remodeling actions in other chondrocyte subclusters and promote the proliferation and maturation of endothelial cells,inducing healing and vascularization processes.Considering that they have substantial remodeling capabilities,these subclusters should be of great interest for tissue engineering studies.We also show that the cellular makeup of the pig meniscus is comparable to that of humans,which supports the use of pigs as a model in orthopedic therapy development. 展开更多
关键词 Single-cell sequencing Transcriptome atlas MENISCUS CHONDROCYTE Pig model Orthopedic
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Rational Design and Fabrication of Cyclotetrasiloxane-based Hybrid Superhydrophobic Fabrics for Oil/Water Separation and Self-cleaning
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作者 Meng-Shu Liu Rungthip Kunthom +1 位作者 Beata Dudziec Hong-Zhi Liu 《Chinese Journal of Polymer Science》 2025年第6期1022-1031,I0011,共11页
Functional superhydrophobic coatings have attracted considerable attention because of their potential for a wide range of applications.In this study,a novel cyclotetrasiloxane-based hybrid superhydrophobic modifier(F-... Functional superhydrophobic coatings have attracted considerable attention because of their potential for a wide range of applications.In this study,a novel cyclotetrasiloxane-based hybrid superhydrophobic modifier(F-D_(4))was prepared for the first time using a mild thiolene click reaction of 2,4,6,8-tetravinyl-2,4,6,8-tetramethylcyclotetrasiloxane(Vi-D_(4))with perfluorohexylethanethiol(PFOT)and mercaptopropyltrimethoxysilane(MPTMS)as the raw materials.Then,F-D_(4) was introduced into the fabric via a sol-gel process,resulting in a superhydrophobic fabric(F-D_(4)-Fabric).The surface characteristics of the modified fabric were determined using scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),and water contact angle(WCA).The coated fabrics have outstanding mechanical,physical,and chemical stability,and exhibit excellent self-cleaning and anti-fouling properties.Owing to its superhydrophobicity,FD_(4)-Fabric could efficiently separate a range of oil/water mixtures with a separation efficiency of up to 99.99%.The study showed that the modification strategy used in the dip-coating process greatly affected the superhydrophobicity of the cotton fabric,which is useful for oil/water separation and self-cleaning applications. 展开更多
关键词 Cyclotetrasiloxane SUPERHYDROPHOBIC Oil/water separation FABRIC COATING
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Rivers increasingly warmer:Prediction of changes in the thermal regime of rivers in Poland
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作者 Mariusz PTAK Teerachai AMNUAYLOJAROEN Mariusz SOJKA 《Journal of Geographical Sciences》 2025年第1期139-172,共34页
Emphasis on future environmental changes grows due to climate change,with simulations predicting rising river temperatures globally.For Poland,which has a long history of thermal studies of rivers,such an approach has... Emphasis on future environmental changes grows due to climate change,with simulations predicting rising river temperatures globally.For Poland,which has a long history of thermal studies of rivers,such an approach has not been implemented to date.This study used 9 Global Climate Models and tested three machine-learning techniques to predict river temperature changes.Random Forest performed best,with R^(2)=0.88 and lowest error(RMSE:2.25,MAE:1.72).The range of future water temperature changes by the end of the 21st century was based on the Shared Socioeconomic Pathway scenarios SSP2-4.5 and SSP5-8.5.It was determined that by the end of the 21st century,the average temperature will increase by 2.1°C(SSP2-4.5)and 3.7°C(SSP5-8.5).A more detailed analysis,divided by two major basins Vistula and Odra,covered about 90%of Poland's territory.The average temperature increase,according to scenarios SSP2-4.5 and SSP5-8.5 for the Odra basin rivers,is 1.6°C and 3.2°C and for the Vistula basin rivers 2.3°C and 3.8°C,respectively.The Vistula basin's higher warming is due to less groundwater input and continental climate influence.These findings provide a crucial basis for water management to mitigate warming effects in Poland. 展开更多
关键词 global warming forecasting water temperature Poland
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水文循环模拟中蒸散发估算方法综述 被引量:43
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作者 赵玲玲 夏军 +3 位作者 许崇育 王中根 苏磊 龙藏瑞 《地理学报》 EI CSCD 北大核心 2013年第1期127-136,共10页
为选取基于水文循环估算蒸散发方法提供依据,首先对常用水文模型中蒸散发估算方法进行回顾,根据其物理机理的强弱性,将水文模型中蒸散估算方法分为整体折算法和分类汇总法。当前水文模型中整体折算法占较大比重,它们之间的差异有两点:... 为选取基于水文循环估算蒸散发方法提供依据,首先对常用水文模型中蒸散发估算方法进行回顾,根据其物理机理的强弱性,将水文模型中蒸散估算方法分为整体折算法和分类汇总法。当前水文模型中整体折算法占较大比重,它们之间的差异有两点:一是潜在蒸散发估算方法不同;二是土壤干燥度折算函数不同;研究表明:由于水文模型存在不确定性及Penman-Monteith方法具有较高资料要求,致使模拟中使用该方法与使用其它简化经验公式相似或更差的水文循环模拟效果。所以对于不同水文模型,如何选取与之复杂程度相兼容的潜在蒸散发估算方程和土壤干燥度折算函数来降低模型的不确定性需进一步讨论。在此基础上,预估基于水文循环估算蒸散发方法朝着复杂机理化和简单实用化两个方向发展。 展开更多
关键词 水文模型 流域蒸散发 潜在蒸散发 土壤可用水函数
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新元古代沂沭海峡地震引发的软沉积物变形及其微量元素信息 被引量:9
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作者 张邦花 田洪水 A.J.(Tom) van Loon 《古地理学报》 CAS CSCD 北大核心 2017年第1期99-116,共18页
新元古代沂沭海峡位于郯庐断裂带昌邑—大店断层西侧宽60~90km、长300km的区域内,其分布范围基本与郯庐断裂带中段一致。新元古代,该海峡盆地先后沉积了青白口系、南华系及震旦系的滨—浅海相陆源碎屑、泥质及碳酸盐沉积物,其岩石... 新元古代沂沭海峡位于郯庐断裂带昌邑—大店断层西侧宽60~90km、长300km的区域内,其分布范围基本与郯庐断裂带中段一致。新元古代,该海峡盆地先后沉积了青白口系、南华系及震旦系的滨—浅海相陆源碎屑、泥质及碳酸盐沉积物,其岩石地层称之为土门群。本次研究从该海峡盆地土门群佟家庄组(由石英砂岩、泥灰岩和页岩组成,属南华系)、浮来山组(由细—粉砂岩夹页岩组成,属震旦系)及石旺庄组(主要由碳酸盐岩组成,下部夹页岩,属震旦系)中鉴别出了一系列地震触动软沉积物形成的变形构造,包括液化砂墙和砂脉、负载构造、火焰构造、球枕构造、软布丁构造、底辟构造、滑塌褶曲和同沉积断层等。它们是地震事件的记录——震积岩。新元古代中晚期(约800—600Ma)沂沭海峡盆地拉张裂陷是它们形成的动力机制。根据石旺庄组中的微亮晶方解石脉与地震成因的变形构造(如负载、火焰、软布丁及同沉积断层等)共(伴)生的事实,并结合模拟地震试验结果分析,认为微亮晶方解石脉很可能是地震引发的饱和灰泥(方解石微粒)液化脉。微量化学元素分析结果表明,这些震积岩中的w(La)/w(Sc)和w(La)/w(Th)值高于上地壳平均值和正常沉积层,而w(Th)/w(Sc)值则较低,深源微量元素Ni和Cr的含量也高于上地壳平均值及正常沉积层。这些微量元素特征是当时的盆地基底不稳定、快速沉积且伴有深部物质元素混入的反映,强地震很可能是快速沉积和促进深源物质混入的主要动力。土门群中发育的一系列地震引起的软沉积物变形(震积岩),再次证明了古郯庐断裂带的存在,由它们记录的地震事件也是晋宁运动乃至Rodinia超大陆的裂解的响应。 展开更多
关键词 软沉积物变形 震积岩 沂沭海峡 盆地裂陷 新元古代 古郯庐断裂带 微量元素信息
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基于碳化钼材料CO_(2)加氢制备高附加值化学品的热催化研究进展 被引量:1
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作者 徐勇庆 杨玉瑶 +10 位作者 武孟娜 杨潇潇 别璇 张时语 李清海 张衍国 张宸伟 Robert EPrzekop Bogna Sztorch Dariusz Brzakaski 周会 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第4期26-51,共26页
CO_(2)加氢对于CO_(2)转化制备高附加值化学品和燃料以实现二氧化碳利用及能源储存至关重要。CO_(2)加氢包括甲烷化、逆水煤气变换、甲醇化和CO_(2)直接费托合成等。碳化钼,尤其是其二维材料,由于其低成本和良好的性能而备受关注。在CO_... CO_(2)加氢对于CO_(2)转化制备高附加值化学品和燃料以实现二氧化碳利用及能源储存至关重要。CO_(2)加氢包括甲烷化、逆水煤气变换、甲醇化和CO_(2)直接费托合成等。碳化钼,尤其是其二维材料,由于其低成本和良好的性能而备受关注。在CO_(2)加氢反应中,由于碳的渗入,导致晶格膨胀以及价电子增加,碳化钼基催化剂展现出了类似于贵金属催化剂的性质。碳化钼可以通过程序升温渗碳法、选择性蚀刻法、机械合金合成法、化学气相沉积法、原位热渗碳法以及溶液相合成法等来制备。到目前为止,学者已经对基于碳化钼的材料的CO_(2)转化进行大量研究,这些材料具有良好的CO_(2)转化活性和对目标产物的选择性。碳化钼材料的催化性能可以通过调节碳化钼中的C/Mo比、在碳化钼与负载金属之间建立强的金属-载体相互作用以及调整材料的界面结构来实现。然而,基于碳化钼的热催化CO_(2)转化仍处于初级阶段。本文综述基于碳化钼的热催化CO_(2)加氢制备高附加值化学品和燃料的研究进展,并分析其面临的挑战和机遇。 展开更多
关键词 CO_(2)加氢 碳化钼 热催化 异相催化 MXenes
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Incidence of human papilloma virus in esophageal squamous cell carcinoma in patients from the Lublin region 被引量:55
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作者 Andrzej Dabrowski Wojciech Kwasniewski +3 位作者 Tomasz Skoczylas Wiesawa Bednarek Dorota Kuzma Anna Gozdzicka-Józefiak 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第40期5739-5744,共6页
AIM:To assess the prevalence of human papilloma virus(HPV) in esophageal squamous cell carcinoma(ESCC) in the south-eastern region of Poland.METHODS:The study population consisted of 56 ESCC patients and 35 controls.T... AIM:To assess the prevalence of human papilloma virus(HPV) in esophageal squamous cell carcinoma(ESCC) in the south-eastern region of Poland.METHODS:The study population consisted of 56 ESCC patients and 35 controls.The controls were patients referred to our department due to other nonesophageal and non-oncological disorders with no gross or microscopic esophageal pathology as confirmed by endoscopy and histopathology.In the ESCC patients,samples were taken from normal mucosa(56 mucosa samples) and from the tumor(56 tumor samples).Tissue samples from the controls were taken from normal mucosa of the middle esophagus(35 control samples).Quantitative determination of DNA was carried out using a spectrophotometric method.Genomic DNA was isolated using the QIAamp DNA Midi Kit.HPV infection was identified following PCR amplification of the HPV gene sequence,using primers MY09 and MY11 complementary to the genome sequence of at least 33 types of HPV.The sequencing results were computationally analyzed using the basic local alignment search tool database.RESULTS:In tumor samples,HPV DNA was identified in 28 of 56 patients(50%).High risk HPV phenotypes(16 or/and 18) were found in 5 of 56 patients(8.9%),low risk in 19 of 56 patients(33.9%) and other types of HPV(37,81,97,CP6108) in 4 of 56 patients(7.1%).In mucosa samples,HPV DNA was isolated in 21 of 56 patients(37.5%).High risk HPV DNA was confirmed in 3 of 56 patients(5.3%),low risk HPV DNA in 12 of 56 patients(21.4%),and other types of HPV in 6 of 56 patients(10.7%).In control samples,HPV DNA was identified in 4 of 35 patients(11.4%) with no high risk HPV.The occurrence of HPV in ESCC patients was significantly higher than in the controls [28 of 56(50%) vs 4 of 35(11.4%),P < 0.001].In esophageal cancer patients,both in tumor and mucosa samples,the predominant HPV phenotypes were low risk HPV,isolated 4 times more frequently than high risk phenotypes [19 of 56(33.9%) vs 5 of 56(8.9%),P < 0.001].A higher prevalence of HPV was identified in female patients(71.4% vs 46.9%).Accordingly,the high risk phenotypes were isolated more frequently in female patients and this difference reached statistical significance [3 of 7(42.9%) vs 2 of 49(4.1%),P < 0.05].Of the pathological characteristics,only an infiltrative pattern of macroscopic tumor type significantly correlated with the presence of HPV DNA in ESCC samples [20 of 27(74.1%) vs 8 of 29(27.6%) for ulcerative or protruding macroscopic type,P < 0.05].The occurrence of total HPV DNA and both HPV high or low risk phenotypes did not significantly differ with regard to particular grades of cellular differentiation,phases in depth of tumor infiltration,grades of nodal involvement and stages of tumor progression.CONCLUSION:Low risk HPV phenotypes could be one of the co-activators or/and co-carcinogens in complex,progressive,multifactorial and multistep esophageal carcinogenesis. 展开更多
关键词 Human papilloma virus Low risk pheno-types High risk phenotypes Esophageal cancer Squa-mous cell carcinoma CARCINOGENESIS
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Nanosized complex fluorides based on Eu^(3+) doped Sr_2LnF_7(Ln=La, Gd) 被引量:9
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作者 M.Runowski S.Balabhadra S.Lis 《Journal of Rare Earths》 SCIE EI CAS CSCD 2014年第3期242-247,共6页
A simple co-precipitation approach taking place between Ln3+, Sr2+ cations and F anions, led to the formation of nanocrystalline Eu3+ doped Sr2LnF7 (Ln-La and Gd) complex fluorides. The reaction was carried out i... A simple co-precipitation approach taking place between Ln3+, Sr2+ cations and F anions, led to the formation of nanocrystalline Eu3+ doped Sr2LnF7 (Ln-La and Gd) complex fluorides. The reaction was carried out in the presence of polyeth- ylene glycol, PEG 6000 as a surfactant/surface modifier, providing small size and homogeneity of the products. The synthesized compounds were composed of small nanoparticles with an average size of 15 nm. All obtained Eu3+ doped compounds exhibited an intensive red luminescence. In the case of gadolinium based compounds, the energy transfer phenomena could be observed from Gd3+ ions to Eu3+ ions. In order to study the structure and morphology of the synthesized fluorides, powder X-ray diffraction (XRD) and transmission electron microscopy (TEM) measurements were performed. Also FT-IR spectra of the products were re- corded, revealing the presence of PEG molecules on the nanoparticles suN'ace. A spectrofluorometry technique was applied to examine optical properties of the synthesized nanoparticles. Excitation and emission spectra as well as luminescence decay curves were measured and analysed. The performed analysis revealed a red luminescence, typical for the Eu3+ ion situated in the inorganic, highly symmetric matrix. Concentration quenching phenomena and lifetimes shortening, together with an increasing of the Eu3+ doping level, were observed and discussed. Judd-Ofelt analysis was also performed for all doped samples, in order to support the registered spectroscopic data and examine in details structural and optoelectronic properties of the synthesized nanomaterials. 展开更多
关键词 luminescence Eu3+ doping complex strontium lanthanide fluorides nanoparticles Sr2LnF7 Sr0.69La0.31F2.31 rare earths
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Depositional and Diagenetic Controls on Sandstone Reservoirs with Low Porosity and Low Permeability in the Eastern Sulige Gas Field, China 被引量:20
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作者 YANG Renchao FAN Aiping +2 位作者 A.J.van LOON HAN Zuozhen WANG Xiuping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第5期1513-1534,共22页
In order to determine the genesis and the factors that control the low-porosity and low- permeability sandstone reservoirs in the eastern Sulige Gas Field in the Ordos Basin, systematic studies on the sedimentary faci... In order to determine the genesis and the factors that control the low-porosity and low- permeability sandstone reservoirs in the eastern Sulige Gas Field in the Ordos Basin, systematic studies on the sedimentary facies and diagenesis were conducted by means of analysis of cores, thin sections, fluid inclusions, X-ray diffraction, cathode luminescence and scanning electron microscope. It was found that the sand bodies of the major gas reservoirs in the Shan1 section (P1S1) and the He8 section (P2H8) were formed during the Permian as sedimentary facies such as braided-channel bars, braided-river channels and point bars of a meandering river. Four types of diagenetic facies developed subsequently: in order from the best to the poorest properties these are type A (weak compaction, early calcite cement-chlorite film facies), type B (moderate compaction, quartz overgrowth-feldspar corrosion-kaolinite filling facies), type C (strong compaction, late calcite cement-quartz corrosion facies) and type D (matrix filling and strong compaction facies). This diagenesis is undoubtedly the main reason for the poor reservoir properties of sandstone reservoirs, but the sedimentary facies are the underlying factors that greatly affect the diagenesis and thus the reservoir performance. Favorable diagenetic facies developed mainly in relatively small lithofacies such as braided-river channels, channel bars and point bars. The vertical distribution of the physical properties and the diagenetic facies of the reservoirs are related to the stratigraphic succession. Most of the sandstones between mudstones and thin beds of sandstone are unfavorable diagenetic facies. Analyses indicate that siliceous cementation can hardly be stopped by hydrocarbon filling. Authigenic chlorite could hardly protect the primary porosity. It not only occupies pore space, but also blocks pathways through sandstone reservoirs, so that it has significant influence on the permeability. Authigenic chlorite cannot be used as a marker for a specific sedimentary facies because it can be formed in different sedimentary facies, but it indicates high hydrodynamic conditions and presence of favorable reservoirs. 展开更多
关键词 Ordos Basin Sulige Gas Field sandstone reservoir sedimentary facies diagenesis diagenetic facies
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Photoluminescent properties of LaF_3:Eu^(3+) and GdF_3:Eu^(3+)nanoparticles prepared by co-precipitation method 被引量:9
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作者 T.Grzyb S.Lis 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第4期588-592,共5页
GdF3:Eu^3+ and GdF3:Eu^3+ nanoparticles were prepared by a co-precipitation method in the presence of the chelating agent, citric acid. The structural properties of the products were characterized by X-ray diffrac... GdF3:Eu^3+ and GdF3:Eu^3+ nanoparticles were prepared by a co-precipitation method in the presence of the chelating agent, citric acid. The structural properties of the products were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The average crystallite size was estimated from the full-width at half-maximum (FWHM) of the diffraction peaks by the Scherrer equation. The sizes of the nanoparticles were 12 nm for LaF3:Eu3+ and 17 nm for GdF3:Eu^3+. The luminescent properties of the nanoparticles were investigated by excitation and emission spectra. Energy transfer from Gd3+ to Eu3+ was observed. 展开更多
关键词 nanofluorides PHOSPHORS LUMINESCENCE energy transfer rare earths
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Neogene Paleoseismic Events and the Shanwang Biota's Burial in the Linqu Area,Shandong Province,China 被引量:7
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作者 TIAN Hongshui A.J.(Tom) VAN LOON +5 位作者 ZHANG Zengqi ZHANG Shenhe ZHANG Banghua Lü Mingying LI Fuchang MA Xuemin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第4期1103-1119,共17页
Several paleoseismic events are recorded in the Neogene Linqu Group, exposed in the Linqu area, Shandong Province, China. The events were interpreted on the basis of fleldwork and laboratory analysis, which showed the... Several paleoseismic events are recorded in the Neogene Linqu Group, exposed in the Linqu area, Shandong Province, China. The events were interpreted on the basis of fleldwork and laboratory analysis, which showed the presence of seismites with plastically deformed soft-sediment deformation structures in the Shanwang Formation, and of seismic volcanic rocks in the Yaoshan Formation which show brittle deformation. The earthquake-triggered soft-sediment deformations in the seismites include load structures, ball-and-pillow structures, flame structures, piUow-like beds, boudinage structures, slump folds, syn-depositional faults, veins of liquefied sand, and dikes of liquefied sandy lime-mud. The seismic activity is also reflected in what might be called 'brittle seismites'; these originated when, under the influence of seismic vibrations, semi-consolidated conglomerate was shattered. Moreover, volcanic activity is related to intense earthquakes that affected basalts intercalated with sand layers; these successions are known as 'seismic volcanic rocks', which are characterized by veins of liquefied sand intruding the basalts. AH above traces of paleoseismic activity were left from one single time span of 4 Ma with active seismicity that took place 14-10 Ma. This time span is known as 'the Linqu Neogene Paleoseismic Active Period', which is divided into four paleoseismic episodes, which were responses to tectonic extension and basin rifting in this area. It even includes the activity of the Yishu Fault Zone during the Miocene and the Neogene. The ratios of trace elements in the seismites, w(La)/w(Sc) and w (La)/w(Th) are higher than the average value of the upper crust, but w(Th)/w(Sc) is lower; this is geochemical evidence for the basin rifting that resulted in a high sedimentation rate. The intense and frequent paleo-earthquakes are held responsible for the rapid burial of the Shanwang Biota. Secondary earthquake-induced processes (e.g. slumping of a lake shore and the strongly increased lacustrine sedimentation rate) contributed to the rapid burial of the biota. 展开更多
关键词 Paleo-seismic event Shanwang biota rapid burial Linqu NEOGENE
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Bifunctional luminescent and magnetic core/shell type nanostructures Fe_3O_4@CeF_3:Tb^(3+)/SiO_2 被引量:5
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作者 M.Runowski T.Grzyb S.Lis 《Journal of Rare Earths》 SCIE EI CAS CSCD 2011年第12期1117-1122,共6页
A facile co-precipitation and microemulsion methods were applied to obtain core/shell type nanoparticles. Cerium fluoride doped with terbittrn(Ⅲ) ions supplied intensive green luminescence of the system. Due to the... A facile co-precipitation and microemulsion methods were applied to obtain core/shell type nanoparticles. Cerium fluoride doped with terbittrn(Ⅲ) ions supplied intensive green luminescence of the system. Due to the presence of magnetite nanoparticles as cores, the prod- uct was highly sensitive to external magnetic field. Both sorts of nanostructures were encapsulated by silica shell. Such external layer of inert oxide can potentially increase the resistance of prepared nanostructttres to thermal oxidation, aggressive agents, changing ofpH or destructive radiation. Morphology of the product was examined using transmission electron microscopy (TEM). Formations of the core/shell type nanostructures were clearly seen in the TEM pictures. Powder X-ray diffraction (XRD) confirmed the structure of the products, their nanocrystallinity and amorphous nature of silica shell. Optical properties were investigated by measuring excitation and emission spectra. Such multifunctional luminescent and magnetic nanoparticles coated with easily functionalized silica shell could be applied in many field of science. 展开更多
关键词 bifunctional nanoparticles magnetic nanoparticles LUMINESCENCE core/shell rare earths
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Impact of urban landscape and environmental externalities on spatial differentiation of housing prices in Yangzhou City 被引量:10
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作者 WANG Yang ZHAO Lingling +2 位作者 SOBKOWIAK Leszek GUAN Xingliang WANG Shaojian 《Journal of Geographical Sciences》 SCIE CSCD 2015年第9期1122-1136,共15页
In this study, housing prices data for residential quarters from the period 2001-2012 were used and Global Differentiation Index (GDI) was established to measure the overall differentiation trend in housing prices i... In this study, housing prices data for residential quarters from the period 2001-2012 were used and Global Differentiation Index (GDI) was established to measure the overall differentiation trend in housing prices in Yangzhou City, eastern China. Then the influence of the natural landscape and environment on prices of global housing market and housing submarkets was evaluated by the hedonic price model. The results are shown as follows. (1) There have been increasing gaps among housing prices since 2001. In this period, the differentiation trend has shown an upward fluctuation, which has been coupled with the annual growth rate of housing prices. (2) The spatial distribution of residential quarters of homogenous prices has changed from clustered in 2001 into dispersed in 2012. (3) Natural landscape and environmental externalities clearly influence spatial differentiation of housing prices. (4) In different housing submarkets, the influence of natural landscape and environmental eternalities are varied. Natural landscape characteristics have significant impact on housing prices of ordinary commercial houses and indemnificatory houses, while the impact of environmental characteristics have obvious influence on housing prices of cottages and villas. 展开更多
关键词 housing prices spatial differentiation GDI index hedonic price method natural landscape ENVIRONMENT Yangzhou
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Gadolinium-modified titanium oxide materials for photoenergy applications:a review 被引量:4
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作者 Maciej Zalas 《Journal of Rare Earths》 SCIE EI CAS CSCD 2014年第6期487-495,共9页
Gadolinium doped titania materials were explored for application in photoenergy production. Incorporation of gadolinium into titania permitted improvement of photocatalytic or photovoltaic performance of the latter. T... Gadolinium doped titania materials were explored for application in photoenergy production. Incorporation of gadolinium into titania permitted improvement of photocatalytic or photovoltaic performance of the latter. This review provided a deep analysis of gadolinium applications in photoenergy processes and devices with the main focus on explanation of gadolinium doping effect on physicochemical properties of titania. 展开更多
关键词 gadolinium doped titania Gd-TiO2 PHOTOCATALYSIS dye-sensitized solar cells photoenergy rare earths
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Luminescence properties of calcium tungstate activated by lanthanide(Ⅲ) ions 被引量:5
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作者 Z.Piskula J.Czajka +1 位作者 K.Staninski S.Lis 《Journal of Rare Earths》 SCIE EI CAS CSCD 2014年第3期221-225,共5页
Calcium tungstate phosphors activated by the Ln3+ ions (Ln-Pr, Nd, Tb, Yb) were synthesized by a traditional high-temperature solid-state method. The crystal structures and morphologies of the products were charact... Calcium tungstate phosphors activated by the Ln3+ ions (Ln-Pr, Nd, Tb, Yb) were synthesized by a traditional high-temperature solid-state method. The crystal structures and morphologies of the products were characterized by scanning electron microscopy (SEM), X-ray powders diffraction (XRD) and infrared spectra (FT-1R). The samples were fotmd to show luminescence properties (down-conversion, DC, at excitation wavelength 254 nm and up-conversion, UC, at excitation wavelength 980 nm). CaWO4 doped with Tb3+/yb3+ showed green DC and UC luminescence characteristic of Tb(Ⅲ) ion in the range of 470-660 nm, cor- responding to the 5D4→7F6,5,4,3,2 electronic transition. CaWO4 doped with Pr3+/Yb3+ showed week blue, green and red (DC and UC) luminescence of Pr(Ⅲ) ion, in the wavelength region of 450-700 nm. Emission peaks were ascribed to the 3P1→3H4,5,6, 3P0→3H4,5,6, 3P1→3F2 and 3P0→3F2 transitions, respectively. CaWO4 doped with Nd3+/yb3+ phosphor emitted orange UC luminescence at 450-690 nm (2p3/2→4I15/2, 4G7/2→419/2,11/2,13/2) and strong near-infrared UC luminescence at 720-900 nm (4F7/2+4S3/2→4419/2, 4F5/2+2H3/2→419/2, 4F3/2→4I9/2) which is the characteristic of Nd(Ⅲ) ion. 展开更多
关键词 LANTHANIDES calcium tungstate UP-CONVERSION LUMINESCENCE rare earths
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Monitoring System of tourist traffic(MSTT) for tourists monitoring in mid-mountain national park,SW Poland 被引量:4
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作者 Mateusz ROGOWSKI 《Journal of Mountain Science》 SCIE CSCD 2020年第8期2035-2047,共13页
National parks are highly valuable natural areas and have the potential to attract a large number of visitors.The number of visitors at national parks is systematically increasing,often exceeding Tourism Carrying Capa... National parks are highly valuable natural areas and have the potential to attract a large number of visitors.The number of visitors at national parks is systematically increasing,often exceeding Tourism Carrying Capacity(TCC)of trails.This situation requires adjusting the number of park visitors to adapt to sustainable management systems of visitor flow,thus preventing or counteracting overtourism.The aim of the study is to propose a comprehensive method for tourists monitoring in mid-mountain national park presented on the example of the Sto?owe Mountains National Park(SMNP)in Poland,called as Monitoring System of tourist traffic(MSTT).The study describes six stages procedure of tourists Monitoring System creation and application as an optimal measurement technique.The MSTT enabled a multidimensional analysis of tourist traffic in SMNP.With the help of 39 pyroelectric sensors and surveys data spatio-temporal characteristic of visitor flow was obtained.The data generated in MSTT included hourly,daily,weekly,monthly,and annual reports,taking into account the direction of traffic measuring both directions:entries(IN),exits(OUT)and passages(IN+OUT).The results from pyroelectric sensors were supplemented with field surveys,where visitor’s motivations,preferences,and behaviours were determined.In 2017 a total of 871,344 visitors were recorded in SMNP what causes one of the most popular national parks in Poland.The SMNP is a suitable destination for short breaks leisure visits in wilderness.In order to sustain MSTT methodology in the long-run the set of guidelines together with the workload estimates were presented.In the future,the MSTT can be further developed,including monitoring of climbing,cycling,cross-country skiing,car traffic and illegal tourism assessment.The MSTT can be considered as a useful tool for tourism management in mid-mountain national parks throughout the entire calendar year. 展开更多
关键词 Tourist traffic Visitor flow Pyroelectric sensors Eco-Counter HIKING Stolowe Mts.National Park
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Evapotranspiration estimation methods in hydrological models 被引量:17
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作者 ZHAO Lingling XIA Jun +3 位作者 XU Chong-yu WANG Zhonggen SOBKOWIAK Leszek LONG Cangrui 《Journal of Geographical Sciences》 SCIE CSCD 2013年第2期359-369,共11页
Actual evapotranspiration is a key process of hydrological cycle and a sole term that links land surface water balance and land surface energy balance.Evapotranspiration plays a key role in simulating hydrological eff... Actual evapotranspiration is a key process of hydrological cycle and a sole term that links land surface water balance and land surface energy balance.Evapotranspiration plays a key role in simulating hydrological effect of climate change,and a review of evapotranspiration estimation methods in hydrological models is of vital importance.This paper firstly summarizes the evapotranspiration estimation methods applied in hydrological models and then classifies them into the integrated converting methods and the classification gathering methods by their mechanism.Integrated converting methods are usually used in hydrological models and two differences exist among them:one is in the potential evaporation estimation methods,while the other in the function for defining relationship between potential evapora tion and actual evapotranspiration.Due to the higher information requirements of the Pen-man-Monteith method and the existing data uncertainty,simplified empirical methods for calculating potential and actual evapotranspiration are widely used in hydrological models.Different evapotranspiration calculation methods are used depending on the complexity of the hydrological model,and importance and difficulty in the selection of the most suitable evapotranspiration methods is discussed.Finally,this paper points out the prospective de velopment trends of the evapotranspiration estimating methods in hydrological modeling. 展开更多
关键词 hydrological model actual evaporation potential evaporation function of soil moisture
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