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教材心理化? 杜威作品中译本对“subject matter”的误译及其影响
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作者 丁道勇 《北京大学教育评论》 北大核心 2023年第4期85-109,188,共26页
把subject matter译作“教材”,使之对等于教学过程中使用的包括教科书在内的各类教学材料,是杜威作品中译本中反复出现的一个译法。通过对杜威作品的中、英文本进行相关比对,可知这是一个误译。在杜威作品中,subject matter指的是“学... 把subject matter译作“教材”,使之对等于教学过程中使用的包括教科书在内的各类教学材料,是杜威作品中译本中反复出现的一个译法。通过对杜威作品的中、英文本进行相关比对,可知这是一个误译。在杜威作品中,subject matter指的是“学科内容”,是各门学科提供的事实和法则,不是教学过程中使用的教科书等教材。“教材心理化”这个中文表达,是subject matter误译的一个直接结果。对这一中文表达的内涵与影响的考察,进一步印证了上述研究发现。Subject matter是杜威反复提及的一个概念,是联系其教育哲学与哲学重建工作的关键词。对subject matter的误译,造成了有关杜威理论的一系列误解。 展开更多
关键词 subject matter 教材 教材心理化 杜威
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CO<sub>2</sub>Absorption Performance of “Dry Matter” Prepared with Amino Acid-Based Ionic Liquids
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作者 Masaya Miyake Mitsuru Satoh 《Green and Sustainable Chemistry》 2017年第3期203-216,共14页
Dry Matter (DM) is a powdery substance which is composed of micro droplets and surrounding hydrophobic silica nanoparticles. Because of the much larger surface area than that of the corresponding bulk liquid, DM, whic... Dry Matter (DM) is a powdery substance which is composed of micro droplets and surrounding hydrophobic silica nanoparticles. Because of the much larger surface area than that of the corresponding bulk liquid, DM, which contains amino-functionalized ionic liquids (ILs), is a promising CO2 absorption material provided with quick absorption speed. In the present study, we successfully prepared powdery DMs by utilizing aqueous solutions of amino acid-based ILs (tetraethylammonium glycine [N2222][Gly], and tetraethylammonium alanine [N2222][Ala]). Although a DM with lysine-based IL (N2222) [Lys]) was also prepared, only a soufflé-like material was obtained. We measured CO2 absorption performance for the DMs to find that the mass-base absorption ability (mass-base A.A.) (CO2 mol/DM kg) and the mol-base one (CO2 mol/IL mol) of [N2222][Lys] were ca. two times of [N2222][Gly] and [N2222][Ala], while the absorption speed of the former was inferior to the latter two, i.e., ca.15 min vs. 5 min for 90% absorption. In order to improve the mass-base A.A. of [N2222][Gly], we used 10% of aqueous poly(allylamine) (PAlAm) solution instead of water. The resultant mass-base A.A. proved to be significantly larger (1.9) than either of those of the respective single component systems (1.1 and 0.75 for the bulk IL and aq. PAlAm, respectively), and comparable to the A.A. (1.6 - 2.5) of 20% - 30% monoethanolamine solution which is commonly used in industrial application. 展开更多
关键词 Dry matter Ionic Liquid CO2 ABSORPTION Amino Acid POLYALLYLAMINE
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Agency of Life, Entropic Gravity and Phenomena Attributed to “Dark Matter”
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作者 Angus McCoss 《Journal of Quantum Information Science》 2017年第2期67-75,共9页
Entropic gravity theories propose that spacetime and gravity emerge from quantum information entanglements. Vacuum spacetime emerges in the ground state and its area law for entanglement entropy is due to short-range ... Entropic gravity theories propose that spacetime and gravity emerge from quantum information entanglements. Vacuum spacetime emerges in the ground state and its area law for entanglement entropy is due to short-range entanglement of neighbouring microscopic degrees of freedom. Matter changes the entanglement entropy in this vacuum and leads to Einstein gravity. Additionally, in a positive dark energy de Sitter Universe, where each conscious agent has a cosmological horizon, a volume law contribution to entanglement entropy is divided evenly over the same degrees of freedom and is caused by long-range entanglement. I propose these complementary shortrange and long-range entanglement contributions form a nested small-world network which provides the topological quantum computing foundation for relativistic multi-agent correlations which weave together a universal physics of Nature. The volume law contribution to entanglement entropy surpasses the area law for entanglement entropy at an agent’s cosmological horizon. Verlinde interprets gravitational “dark matter” phenomena as polymer-like memory effects caused by the volume contribution to the entanglement entropy. I propose these phenomena are instead multi-agent quantum computational consensus effects due to an equivalent volume contribution to the entanglement entropy. Life is correlated with its environment. Phenomena attributed to unseen “dark matter” particles are proposed here to be founded upon nested observer halos, “spheres of influence or correlation”, caused by the consensus Agency of Life. Suitable cosmological conditions for earliest Life in the Universe occurred some 10 billion years ago and older galaxies do not exhibit “dark matter” phenomena. Also, galactic rotation curves flatten beyond their high-radiation centres, due to astrobiology and the Agency of Life living in outlying low-radiation habitable zones. Where baryonic matter is in motion, then the Agency of Life stores its baryonic matter-lagging memory in skewed trails of apparent “dark matter” phenomena in spacetime. 展开更多
关键词 ENTANGLEMENT Entropy DARK matter SMALL-WORLD Network ASTROBIOLOGY CONSCIOUSNESS
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Galaxies “Boiling off” Electrons Due to the Photo-Electric Effect Leading to a New Model of the IGM and a Possible Mechanism for “Dark Matter”
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作者 Lyndon Ashmore 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第1期181-192,共12页
The Intergalactic Medium (IGM) is commonly thought to be occupied by approximately one atom of Hydrogen per cubic metre of space either as neutral Hydrogen or partially/fully ionised. This cannot be true as galaxies w... The Intergalactic Medium (IGM) is commonly thought to be occupied by approximately one atom of Hydrogen per cubic metre of space either as neutral Hydrogen or partially/fully ionised. This cannot be true as galaxies will “boil off” electrons from their outer surfaces by the photo-electric effect and so the IGM must be filled with electrons. UV and X-ray photons, as they leave the galaxy, can remove an electron from a Hydrogen atom at the surface of the galaxy, give it sufficient energy to escape the gravitational pull of the galaxy and go on to fill the IGM. A typical galaxy emits approximately 5×1047 X-ray photons each second. All of which pass through the outer surface of the galaxy and have sufficient energy to eject an electron and send it off to the IGM. Adding to these photons in the UV and gamma, we can see that galaxies are ejecting large amounts of electrons each second that go on to fill the IGM. Data from FRB 121102 give the value for the electron number density in the IGM as ne ≈ 0.5 m-3. Under certain conditions, an electron gas will crystallise into a Wigner-Seitz crystal. Here the electrical potential energy of repulsion between the electrons dominates their kinetic energy and the electrons form on a BCC lattice structure. The electrons oscillate, performing SHM about their lattice positions. With ne ≈ 0.5 m-3 the electrons in the IGM satisfy the energy criteria for crystallisation to occur when interacting with other electrons within a sphere far less in radius than the corresponding Debye sphere. Thus, the conditions are met for the electrons to form an “electron glass.” Since the electrons in their BCC formation are spatially coherent, light will travel through the crystals in a straight line and thus objections to “Tired Light” theories are now removed since images will neither be destroyed nor “blurred.” Charges are not created but separated, if the electrons are removed from the galaxy and sent to fill the IGM;the remaining protons are left behind. These are “thermal” and will not have sufficient energy to escape but will be held gravitationally to that galaxy. Could these too form a spherical Wigner-Seitz sphere around that galaxy? Since the structure would be transparent, light would pass through in straight lines and thus we would not see it. They would however, interact gravitationally with the galaxy and have an effect on the rotation curves of single galaxies and on the motion of galactic clusters. Just as we cannot see the clear water in a fish tank when we look at the fish, the transparent, crystalline sphere of protons around galaxies would be “dark”. 展开更多
关键词 Intergalactic Medium IGM GALAXIES Dark matter REDSHIFTS CMBR Tired Light WIGNER Crystals
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Equivalence between a Gravity Field and an Unruh Acceleration Temperature Field as a Possible Clue to “Dark Matter”
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作者 Eugene Terry Tatum U. V. S. Seshavatharam 《Journal of Modern Physics》 2018年第8期1568-1572,共5页
Einstein’s equivalence principle allows one to compare the magnitudes of a gravitational acceleration field with the magnitudes of a field of Unruh acceleration temperatures. The validity of such a comparison is demo... Einstein’s equivalence principle allows one to compare the magnitudes of a gravitational acceleration field with the magnitudes of a field of Unruh acceleration temperatures. The validity of such a comparison is demonstrated by using it to derive the effective Hawking black body radiation at a Schwarzschild black hole horizon. One can then extend the black hole thought experiment to a Hawking-Unruh temperature equation expressed in terms of the Schwarzschild radius. This follows an inverse radius law rather than an inverse radius-squared law. Following a brief discussion of current theoretical failures to explain galactic rotation curves, the Unruh acceleration temperature equations are brought together to show how a rotating supermassive black hole galactic system should follow an inverse radius rule of centripetal gravitational force and centripetal acceleration. This result appears to indicate that galactic observations currently attributed to dark matter may in part be attributed to classical Newtonian dynamics superimposed on a relativistic rotating system powered by a supermassive black hole. 展开更多
关键词 DARK matter Unruh Effect Unruh Temperature Supermassive Black HOLES GALACTIC Rotation CURVES EQUIVALENCE Principle Hawking Radiation
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A New Approach: About the Appearance of “Dark Matter” Effects in the Process of Expansion of the Universe*
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作者 Leonid Sitnikov 《Journal of Modern Physics》 2021年第7期1040-1047,共8页
The paper considers cosmological objects belonging to fundamentally different classes that do not intersect with each other. Firstly, these are objects that make up a pure Hubble stream. Secondly, these are objects th... The paper considers cosmological objects belonging to fundamentally different classes that do not intersect with each other. Firstly, these are objects that make up a pure Hubble stream. Secondly, these are objects that have constant proper distances. These include planets, stars, and galaxies in gravitationally coupled systems. They all do not participate in the Hubble stream as independent objects. It is shown that the commoving reference system and proper reference system standardly used in cosmology change places with each other when switching from considering Hubble objects to “planets”. The features of the evolution (more precisely, devolution, degradation, reverse development) of the latter were analyzed and it was found that the cosmological acceleration of all “planets”, in contrast to Hubble objects, coincides in order of magnitude with the fundamental value of <em>H</em><sup><em>2</em></sup><em>R</em>. As applied to the Pioneers anomaly, this approach allowed us to obtain the calculated value of cosmological acceleration, which coincides in order of magnitude with the observed value. It seems that this approach is applicable also to other local gravitationally coupled systems and allows us to explain the characteristic flattened shape of the orbital curves of stars and galaxies by the fact that the influence of the fundamental cosmological acceleration <em>H</em><sup><em>2</em></sup><em>R</em> is added to the system’s own gravitational field. 展开更多
关键词 Dark matter Expansion of the Universe Anomalous Pioneer Effect
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Facts Show July 5 Riot “Far Beyond Ordinary Violent Matter”
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《The Journal of Human Rights》 2009年第5期5-7,共3页
Nearly two weeks after the July 5 riot in Urumqi of northwest China's Xinjiang Uygur Autonomous Region, social order and people's lives are returning to normal. Yet in retrospect, a mass of evidences show that the u... Nearly two weeks after the July 5 riot in Urumqi of northwest China's Xinjiang Uygur Autonomous Region, social order and people's lives are returning to normal. Yet in retrospect, a mass of evidences show that the unrest was a wellplanned violent criminal incident of terrorist nature. 展开更多
关键词 bus Far Beyond Ordinary Violent matter Facts Show July 5 Riot SHOW
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A pressure-sensitive rheological origin of high friction angles of granular matter observed in NASA–MGM project
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作者 程晓辉 肖世泽 +2 位作者 杨森 赵乃峰 Alex Sixie Cao 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期559-567,共9页
An abnormally high peak friction angle of Ottawa sand was observed in(National Aeronautics and Space Administration) NASA–(Mechanics of Granular Materials) MGM tests in microgravity conditions on the space shuttle. P... An abnormally high peak friction angle of Ottawa sand was observed in(National Aeronautics and Space Administration) NASA–(Mechanics of Granular Materials) MGM tests in microgravity conditions on the space shuttle. Previous investigations have been unsuccessful in providing a constitutive insight into this behavior of granular materials under extremely low effective stress conditions. Here, a recently proposed unified constitutive model for transient rheological behavior of sand and other granular materials is adopted for the analytical assessment of high peak friction angles. For the first time, this long-eluded behavior of sand is attributed to a hidden rheological transition mechanism, that is not only rate-sensitive, but also pressure-sensitive. The NASA–MGM microgravity conditions show that shear-tests of sand can be performed under abnormally low confining stress conditions. The pressure-sensitive behavior of granular shearing that is previously ignored is studied based on the μ(I) rheology and its variations. Comparisons between the model and the NASA microgravity tests demonstrate a high degree of agreement. The research is highly valid for pressure-sensitive and rate-dependent problems that occur during earthquakes, landslides, and space exploration. 展开更多
关键词 granular matter MICROGRAVITY pressure-sensitive NASA–MGM
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Straw mulching alters the composition and loss of dissolved organic matter in farmland surface runoff by inhibiting the fragmentation of soil small macroaggregates
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作者 Shanshan Cai Lei Sun +7 位作者 Wei Wang Yan Li Jianli Ding Liang Jin Yumei Li Jiuming Zhang Jingkuan Wang Dan Wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1703-1717,共15页
Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How st... Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How straw mulching affects the composition and loss of runoff DOM by changing soil aggregates remains largely unclear.Here,a straw mulching treatment was compared to a no mulching treatment(as a control)on sloping farmland with black soil erosion in Northeast China.We divided the soil into large macroaggregates(>2 mm),small macroaggregates(0.25-2 mm),and microaggregates(<0.25 mm).After five rain events,the effects of straw mulching on the concentration(characterized by dissolved organic carbon(DoC)and composition(analyzed by fluorescence spectroscopy)of runoff and soil aggregate DOM were studied.The results showed that straw mulching reduced the runoff amount by 54.7%.Therefore,although straw mulching increased the average DOc concentration in runoff,it reduced the total runoff DOM loss by 48.3%.The composition of runoff DOM is similar to that of soil,as both contain humic-like acid and protein-like components.With straw mulching treatment,the protein-like components in small macroaggregates accumulated and the protein-like components in runoff declined with rain events.Fluorescence spectroscopy technology may help in understanding the hydrological paths of rain events by capturing the dynamic changes of runoff and soil DOM characteristics.A variation partitioning analysis(VPA)indicated that the DOM concentration and composition of microaggregates explained 68.2%of the change in runoff DOM from no mulching plots,while the change in runoff DOM from straw mulching plots was dominated by small macroaggregates at a rate of 55.1%.Taken together,our results demonstrated that straw mulching reduces the fragmentation of small macroaggregates and the loss of microaggregates,thus effecting DOM compositions in soil and reducing the DOM loss in runoff.These results provide a theoretical basis for reducing carbon loss in sloping farmland. 展开更多
关键词 dissolved organic matter black soil surface runoff AGGREGATES fluorescence spectrum
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Biogeochemistry of sedimentary organic matter in the Yongjiang River estuary in the southern part of Hangzhou Bay,China,since the Late Pleistocene
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作者 Dongqin HUANG Xiaolong LI +6 位作者 Zilong LI Pei Sun LOH Jianxiong HU Jianfang CHEN Yuan-Pin CHANG Chin-Wen YANG Qin GAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期772-786,共15页
A sediment core(YJK19-02)collected from the southern outlet of Hangzhou Bay near the Yongjiang River estuary in East China was analyzed for grain size,lignin,bulk elemental composition,stable carbon isotope,and rare e... A sediment core(YJK19-02)collected from the southern outlet of Hangzhou Bay near the Yongjiang River estuary in East China was analyzed for grain size,lignin,bulk elemental composition,stable carbon isotope,and rare earth elements(REEs)to determine the sources and diagenesis of sedimentary organic matter(OM)of the estuary and adjacent areas since the Late Pleistocene.δ^(13)C values(-24.80‰–-23.60‰),total organic carbon/total nitrogen(TOC/TN)molar ratios(8.00–12.14),and light rare earth element/heavy rare earth element ratios(LREE/HREE=8.34–8.91)revealed the predominance of terrestrial sources of OM,mainly from the Changjiang(Yangtze)River.The lignin parameters of syringyl/vanillyl(S/V=0.20–0.73)and cinnamyl/vanillyl(C/V=0.03–0.19)ratios indicate the predominance of nonwoody angiosperms,and the vanillic acid/vanillin ratios[(Ad/Al)_(V)=0.32–1.57]indicate medium to high degrees of lignin degradation.An increasing trend ofΛ(total lignin in mg/100-mg OC)values from ca.14500 a BP to ca.11000 a BP reflected the increase in temperature during the Late Pleistocene.However,a time lag effect of temperature on vegetation abundance was also revealed.The relatively higher and stableΛvalues correspond to the higher temperature during the mid-Holocene from ca.8500 a BP to ca.4500 a BP.Λvalues decreased from ca.4000 a BP to the present,corresponding to historical temperature fluctuations during this time.Our results show that the vegetation abundance in the Yongjiang River Basin since the Late Pleistocene was related to the temperature fluctuation duo to climate change. 展开更多
关键词 Yongjiang River estuary sedimentary organic matter LIGNIN environmental change Late Pleistocene
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Subtropical forest macro-decomposers rapidly transfer litter carbon and nitrogen into soil mineral-associated organic matter
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作者 Guoxiang Niu Tao Liu +4 位作者 Zhen Zhao Xuebing Zhang Huiling Guan Xiaoxiang He Xiankai Lu 《Forest Ecosystems》 SCIE CSCD 2024年第2期131-139,共9页
Background:Forest soils in tropical and subtropical areas store a significant amount of carbon.Recent framework to assess soil organic matter(SOM)dynamics under evolving global conditions suggest that dividing bulk SO... Background:Forest soils in tropical and subtropical areas store a significant amount of carbon.Recent framework to assess soil organic matter(SOM)dynamics under evolving global conditions suggest that dividing bulk SOM into particulate and mineral-associated organic matter(POM vs.MAOM)is a promising method for identifying how SOM contributes to reducing global warming.Soil macrofauna,earthworms,and millipedes have been found to play an important role in facilitating SOM processes.However,how these two co-existing macrofaunae impac the litter decomposition process and directly impact the formation of POM and MAOM remains unclear.Methods:Here,we set up a microcosm experiment,which consisted of 20 microcosms with four treatments earthworm and litter addition(E),millipedes and litter addition(M),earthworm,millipedes,and litter addition(E+M),and control(only litter addition)in five replicates.The soil and litter were sterilized prior to beginning the incubation experiment to remove any existing microbes.After incubating the samples for 42 days,the litte properties(mass,C,and N contents),soil physicochemical properties,as well as the C and N contents,and POM and MAOM^(13)C abundance in the 0–5 and 5–10 cm soil layers were measured.Finally,the relative influences o soil physicochemical and microbial properties on the distribution of C and N in the soil fractions were analyzed Results:The litter mass,C,and N associated with all four treatments significantly decreased after incubation especially under treatment E+M(litter mass:-58.8%,litter C:-57.0%,litter N:-75.1%,respectively),while earthworm biomass significantly decreased under treatment E.Earthworm or millipede addition alone showed no significant effects on the organic carbon(OC)and total nitrogen(TN)content in the POM fraction,but join addition of both significantly increased OC and TN regardless of soil depth.Importantly,all three macrofauna treatments increased the OC and TN content and decreased the^(13)C abundance in the MAOM fraction.More than65%of the total variations in the distribution of OC and TN throughout the two fractions can be explained by a combination of soil physicochemical and microbial properties.Changes in the OC distribution in the 0–5 cm soi layer are likely due to a decrease in soil pH and an increase in arbuscular mycorrhizal fungi(AMF),while those in the 5–10 cm layer are probably caused by increases in soil exchangeable Ca and Mg,in addition to fungi and gram-negative(GN)bacteria.The observed TN distribution changes in the 0–5 cm soil likely resulted from a decrease in soil pH and increases in AMF,GN,and gram-negative(GP)bacteria,while TN distribution changes in the 5–10 cm soil could be explained by increases in exchangeable Mg and GN bacteria.Conclusions:The results indicate that the coexistence of earthworms and millipedes can accelerate the litte decomposition process and store more C in the MAOM fractions.This novel finding helps to unlock the processe by which complex SOM systems serve as C sinks in tropical forests and addresses the importance of soil mac rofauna in maintaining C-neutral atmospheric conditions under global climate change. 展开更多
关键词 Tropical and subtropical forest Soil organic matter fractions EARTHWORM MILLIPEDES Litter decomposition
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Ethyl acetate fraction of Sargassum pallidum extract attenuates particulate matter-induced oxidative stress and inflammation in keratinocytes and zebrafish
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作者 Wook Chul Kim Ji-Won Park +3 位作者 Bohyun Yun WonWoo Lee Kyung-Min Choi Seung-Hong Lee 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第4期137-146,共10页
Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCa... Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCaT cells and zebrafish were used to evaluate the protective effects of the ethyl acetate fraction of Sargassum pallidum extract against PM-induced oxidative stress and inflammation.The production of nitric oxide(NO),intracellular ROS,prostaglandin E_(2)(PGE_(2)),and pro-inflammatory cytokines,and the expression levels of COX-2,iNOS,and NF-κB were evaluated in PM-induced HaCaT cells.Furthermore,the levels of ROS,NO,and lipid peroxidation were assessed in the PM-exposed zebrafish model.Results:The ethyl acetate fraction of Sargassum pallidum extract significantly decreased the production of NO,intracellular ROS,and PGE_(2) in PM-induced HaCaT cells.In addition,the fraction markedly suppressed the levels of pro-inflammatory cytokines and inhibited the expression levels of COX-2,iNOS,and NF-κB.Furthermore,it displayed remarkable protective effects against PM-induced inflammatory response and oxidative stress,represented by the reduction of NO,ROS,and lipid peroxidation in zebrafish.Conclusions:The ethyl acetate fraction of Sargassum pallidum extract exhibits a protective effect against PM-induced oxidative stress and inflammation both in vitro and in vivo and has the potential as a candidate for the development of pharmaceutical and cosmeceutical products. 展开更多
关键词 Particulate matter INFLAMMATION Oxidative stress Sargassum pallidum Ethyl acetate fraction ZEBRAFISH
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Differences in and factors controlling organic matter enrichment in the Ziliujing Formation shale in the Sichuan Basin
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作者 Peng Li Zhong-Bao Liu +4 位作者 He Bi Tao Jiang Rui-Kang Bian Peng-Wei Wang Xiao-Yu Shang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期77-86,共10页
Lacustrine shale oil and gas are important fields for unconventional exploration and development in China,and organic-rich shale deposition lays down the critical foundation for hydrocarbon generation.There are two se... Lacustrine shale oil and gas are important fields for unconventional exploration and development in China,and organic-rich shale deposition lays down the critical foundation for hydrocarbon generation.There are two sets of shale,the Dongyuemiao and Da’anzhai Members,in the Ziliujing Formation in the Sichuan Basin.To identify the differential enrichment characteristics of organic matter and clarify its controlling factors,geochemical analyses of organic and inorganic geochemical analyses were performed.The results showed that the total organic carbon content of the Dongyuemiao shale(1.36%)is slightly higher than that of the Da’anzhai shale(0.95%).The enrichment of organic matter in the two shales resulted from the comprehensive controls of paleoproductivity,paleoenvironment,and terrigenous input,but different factors have different effects.In addition,driven by climate,the change in the sulfate concentration in the bottom water further led to the different intensities of bacterial sulfate reduction in early diagenesis.This made a great difference regarding organic matter accumulation in the two members.In general,climate may have played a dominant role in organic matter enrichment in the two sets of shale. 展开更多
关键词 Lacustrine shale Ziliujing Formation Sichuan Basin Enrichment mechanism of organic matter
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Mapping soil organic matter in cultivated land based on multi-year composite images on monthly time scales
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作者 Jie Song Dongsheng Yu +4 位作者 Siwei Wang Yanhe Zhao Xin Wang Lixia Ma Jiangang Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1393-1408,共16页
Rapid and accurate acquisition of soil organic matter(SOM)information in cultivated land is important for sustainable agricultural development and carbon balance management.This study proposed a novel approach to pred... Rapid and accurate acquisition of soil organic matter(SOM)information in cultivated land is important for sustainable agricultural development and carbon balance management.This study proposed a novel approach to predict SOM with high accuracy using multiyear synthetic remote sensing variables on a monthly scale.We obtained 12 monthly synthetic Sentinel-2 images covering the study area from 2016 to 2021 through the Google Earth Engine(GEE)platform,and reflectance bands and vegetation indices were extracted from these composite images.Then the random forest(RF),support vector machine(SVM)and gradient boosting regression tree(GBRT)models were tested to investigate the difference in SOM prediction accuracy under different combinations of monthly synthetic variables.Results showed that firstly,all monthly synthetic spectral bands of Sentinel-2 showed a significant correlation with SOM(P<0.05)for the months of January,March,April,October,and November.Secondly,in terms of single-monthly composite variables,the prediction accuracy was relatively poor,with the highest R^(2)value of 0.36 being observed in January.When monthly synthetic environmental variables were grouped in accordance with the four quarters of the year,the first quarter and the fourth quarter showed good performance,and any combination of three quarters was similar in estimation accuracy.The overall best performance was observed when all monthly synthetic variables were incorporated into the models.Thirdly,among the three models compared,the RF model was consistently more accurate than the SVM and GBRT models,achieving an R^(2)value of 0.56.Except for band 12 in December,the importance of the remaining bands did not exhibit significant differences.This research offers a new attempt to map SOM with high accuracy and fine spatial resolution based on monthly synthetic Sentinel-2 images. 展开更多
关键词 soil organic matter Sentinel-2 monthly synthetic images machine learning model spatial prediction
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Improved simulation of winter wheat yield in North China Plain by using PRYM-Wheat integrated dry matter distribution coefficient
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作者 Xuan Li Shaowen Wang +6 位作者 Yifan Chen Danwen Zhang Shanshan Yang Jingwen Wang Jiahua Zhang Yun Bai Sha Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1381-1392,共12页
The accurate simulation of regional-scale winter wheat yield is important for national food security and the balance of grain supply and demand in China.Presently,most remote sensing process models use the“biomass... The accurate simulation of regional-scale winter wheat yield is important for national food security and the balance of grain supply and demand in China.Presently,most remote sensing process models use the“biomass×harvest index(HI)”method to simulate regional-scale winter wheat yield.However,spatiotemporal differences in HI contribute to inaccuracies in yield simulation at the regional scale.Time-series dry matter partition coefficients(Fr)can dynamically reflect the dry matter partition of winter wheat.In this study,Fr equations were fitted for each organ of winter wheat using site-scale data.These equations were then coupled into a process-based and remote sensingdriven crop yield model for wheat(PRYM-Wheat)to improve the regional simulation of winter wheat yield over the North China Plain(NCP).The improved PRYM-Wheat model integrated with the fitted Fr equations(PRYM-Wheat-Fr)was validated using data obtained from provincial yearbooks.A 3-year(2000-2002)averaged validation showed that PRYM-Wheat-Fr had a higher coefficient of determination(R^(2)=0.55)and lower root mean square error(RMSE=0.94 t ha^(-1))than PRYM-Wheat with a stable HI(abbreviated as PRYM-Wheat-HI),which had R^(2) and RMSE values of 0.30 and 1.62 t ha^(-1),respectively.The PRYM-Wheat-Fr model also performed better than PRYM-Wheat-HI for simulating yield in verification years(2013-2015).In conclusion,the PRYM-Wheat-Fr model exhibited a better accuracy than the original PRYM-Wheat model,making it a useful tool for the simulation of regional winter wheat yield. 展开更多
关键词 dry matter partition remote sensing model winter wheat yield North China Plain
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Impacts of Water-Sediment Regulation Scheme on Chromophoric Dissolved Organic Matter in the Lower Yellow River
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作者 LIU Xiao JIANG Xueyan +2 位作者 LIU Qian SUI Juanjuan ZOU Li 《Journal of Ocean University of China》 CAS CSCD 2024年第2期455-466,共12页
As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water quality.Water-sediment regulation scheme(WSRS),which has been c... As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water quality.Water-sediment regulation scheme(WSRS),which has been carried out annually in the Yellow River since 2002,is a typical human activity affecting river water quality.Chromophoric dissolved organic matter(CDOM)in river is susceptible to changes in ecological and environmental conditions as well as human activities.Here,we report variations in dissolved organic carbon concentrations,compositions and sources of CDOM in time series samples in the lower Yellow River during WSRS.In addition,a parallel factor fluorescence analysis(PARAFAC)method is applied to identify different fluorescent components in water samples during WRSR,showing four major components including tryptophan-like component(C1),microbial humic-like component(C2),terrestrial humic-like component(C3)and tyrosine-like component(C4).In general,C1 increased after water regulation,while C2 and C3 increased after sediment regulation,indicating that the water and sediment released by the dam have different effects on CDOM compositions.Under the impacts of the dam,source of CDOM in the lower Yellow River is mainly autochthonous related to microbial activities,and is regulated by the terrestrial input during WSRS period.Sediment resuspension inhibits microbial activities and reduces the production of autochthonous CDOM.Overall,human activities especially WSRS,as exemplified here,significantly alter the quality and quantity of CDOM in the lower Yellow River,affecting CDOM dynamics and biogeochemical processes in the estuarine environment. 展开更多
关键词 chromophoric dissolved organic matter(CDOM) water-sediment regulation scheme(WSRS) Yellow River optical properties
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Implications of the Stellar Mass Density of High-z Massive Galaxies from JWST on Warm Dark Matter
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作者 Hengjie Lin Yan Gong +1 位作者 Bin Yue Xuelei Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期128-134,共7页
A significant excess of the stellar mass density at high redshift has been discovered from the early data release of James Webb Space Telescope(JWST),and it may require a high star formation efficiency.However,this wi... A significant excess of the stellar mass density at high redshift has been discovered from the early data release of James Webb Space Telescope(JWST),and it may require a high star formation efficiency.However,this will lead to large number density of ionizing photons in the epoch of reionization(EoR),so that the reionization history will be changed,which can arise tension with the current EoR observations.Warm dark matter(WDM),via the free streaming effect,can suppress the formation of small-scale structure as well as low-mass galaxies.This provides an effective way to decrease the ionizing photons when considering a large star formation efficiency in high-z massive galaxies without altering the cosmic reionization history.On the other hand,the constraints on the properties of WDM can be derived from the JWST observations.In this work,we study WDM as a possible solution to reconcile the JWST stellar mass density of high-z massive galaxies and reionization history.We find that,the JWST high-z comoving cumulative stellar mass density alone has no significant preference for either CDM or WDM model.But using the observational data of other stellar mass density measurements and reionization history,we obtain that the WDM particle mass with mw=0.51_(-0.12)^(+0.22) keV and star formation efficiency parameter f_(*)^(0)> 0.39 in 2σ confidence level can match both the JWST high-z comoving cumulative stellar mass density and the reionization history. 展开更多
关键词 COSMOLOGY (cosmology:)dark matter (cosmology:)large-scale structure of universe
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Performance of the walking trail making test in older adults with white matter hyperintensities
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作者 Hong-Yi Zhao Zhi-Qiang Zhang +2 位作者 Yong-Hua Huang Hong Li Fang-Yuan Wei 《World Journal of Psychiatry》 SCIE 2024年第1期102-110,共9页
BACKGROUND Several studies have reported that the walking trail making test(WTMT)completion time is significantly higher in patients with developmental coordination disorders and mild cognitive impairments.We hypothes... BACKGROUND Several studies have reported that the walking trail making test(WTMT)completion time is significantly higher in patients with developmental coordination disorders and mild cognitive impairments.We hypothesized that WTMT performance would be altered in older adults with white matter hyperintensities(WMH).AIM To explore the performance in the WTMT in older people with WMH.METHODS In this single-center,observational study,25 elderly WMH patients admitted to our hospital from June 2019 to June 2020 served as the WMH group and 20 participants matched for age,gender,and educational level who were undergoing physical examination in our hospital during the same period served as the control group.The participants completed the WTMT-A and WTMT-B to obtain their gait parameters,including WTMT-A completion time,WTMT-B completion time,speed,step length,cadence,and stance phase percent.White matter lesions were scored according to the Fazekas scale.Multiple neuropsychological assessments were carried out to assess cognitive function.The relationships between WTMT performance and cognition and motion in elderly patients with WMH were analyzed by partial Pearson correlation analysis.RESULTS Patients with WMH performed significantly worse on the choice reaction test(CRT)(0.51±0.09 s vs 0.44±0.06 s,P=0.007),verbal fluency test(VFT,14.2±2.75 vs 16.65±3.54,P=0.012),and digit symbol substitution test(16.00±2.75 vs 18.40±3.27,P=0.010)than participants in the control group.The WMH group also required significantly more time to complete the WTMT-A(93.00±10.76 s vs 70.55±11.28 s,P<0.001)and WTMT-B(109.72±12.26 s vs 82.85±7.90 s,P<0.001).WTMT-A completion time was positively correlated with CRT time(r=0.460,P=0.001),while WTMT-B completion time was negatively correlated with VFT(r=-0.391,P=0.008).On the WTMT-A,only speed was found to statistically differ between the WMH and control groups(0.803±0.096 vs 0.975±0.050 m/s,P<0.001),whereas on the WTMT-B,the WMH group exhibited a significantly lower speed(0.778±0.111 vs 0.970±0.053 m/s,P<0.001)and cadence(82.600±4.140 vs 85.500±5.020 steps/m,P=0.039),as well as a higher stance phase percentage(65.061±1.813%vs 63.513±2.465%,P=0.019)relative to controls.CONCLUSION Older adults with WMH showed obviously poorer WTMT performance.WTMT could be a potential indicator for cognitive and motor deficits in patients with WMH. 展开更多
关键词 White matter hyperintensities Cognitive dysfunction Motor deficits Gait analysis Trail making test Small vessel disease
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Neuropathological characteristics of abnormal white matter functional signaling in adolescents with major depression
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作者 Xin-Lin Huang Ju Gao +5 位作者 Yong-Ming Wang Feng Zhu Jing Qin Qian-Nan Yao Xiao-Bin Zhang Hong-Yan Sun 《World Journal of Psychiatry》 SCIE 2024年第2期276-286,共11页
BACKGROUND Major depression disorder(MDD)constitutes a significant mental health concern.Epidemiological surveys indicate that the lifetime prevalence of depression in adolescents is much higher than that in adults,wi... BACKGROUND Major depression disorder(MDD)constitutes a significant mental health concern.Epidemiological surveys indicate that the lifetime prevalence of depression in adolescents is much higher than that in adults,with a corresponding increased risk of suicide.In studying brain dysfunction associated with MDD in adolescents,research on brain white matter(WM)is sparse.Some researchers even mistakenly regard the signals generated by the WM as noise points.In fact,studies have shown that WM exhibits similar blood oxygen level-dependent signal fluctuations.The alterations in WM signals and their relationship with disease severity in adolescents with MDD remain unclear.AIM To explore potential abnormalities in WM functional signals in adolescents with MDD.METHODS This study involved 48 adolescent patients with MDD and 31 healthy controls(HC).All participants were assessed using the Patient Health Questionnaire-9 Scale and the mini international neuropsychiatric interview(MINI)suicide inventory.In addition,a Siemens Skyra 3.0T magnetic resonance scanner was used to obtain the subjects'image data.The DPABI software was utilized to calculate the WM signal of the fractional amplitude of low frequency fluctuations(fALFF)and regional homogeneity,followed by a two-sample t-test between the MDD and HC groups.Independent component analysis(ICA)was also used to evaluate the WM functional signal.Pearson’s correlation was performed to assess the relationship between statistical test results and clinical scales.RESULTS Compared to HC,individuals with MDD demonstrated a decrease in the fALFF of WM in the corpus callosum body,left posterior limb of the internal capsule,right superior corona radiata,and bilateral posterior corona radiata[P<0.001,family-wise error(FWE)voxel correction].The regional homogeneity of WM increased in the right posterior limb of internal capsule and left superior corona radiata,and decreased in the left superior longitudinal fasciculus(P<0.001,FWE voxel correction).The ICA results of WM overlapped with those of regional homogeneity.The fALFF of WM signal in the left posterior limb of the internal capsule was negatively correlated with the MINI suicide scale(P=0.026,r=-0.32),and the right posterior corona radiata was also negatively correlated with the MINI suicide scale(P=0.047,r=-0.288).CONCLUSION Adolescents with MDD involves changes in WM functional signals,and these differences in brain regions may increase the risk of suicide. 展开更多
关键词 White matter Regional homogeneity The fractional amplitude of low-frequency fluctuations Independent component analysis Adolescents Major depression disorders
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The Structure of Gravity Funnels and Stability Considerations of Matter in SI Units
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作者 Tobias Bartusch 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期71-81,共11页
This article describes an extension of the theory of vortices to electromagnetic types with a start point from known fluid systems. From this, properties of gravity-generating objects (particles and black holes) can b... This article describes an extension of the theory of vortices to electromagnetic types with a start point from known fluid systems. From this, properties of gravity-generating objects (particles and black holes) can be derived, which can also describe their possible interior. This also leads to questions about stability, which are then addressed and ultimately lead to considerations of black holes and their possible internal structure. The results fit into the observable areas and can also be directly verified because they were analytically calculated in SI units. 展开更多
关键词 Black Hole Dark matter Electromagnetic GRAVITY SINGULARITY VORTEX
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