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Constraints on what controls millennial-scale basin-wide denudation across mountain belts, Asia

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science China earth sciences 2025年第1期 74-93页

作者： Ye YANG Steven A.BINNIE Sheng XU Cong-Qiang LIU Tibor J.DUNAI Institute of Surface-earth System science School of Earth System Science Tianjin University Institute of Geology and Mineralogy University of Cologne

The terrestrial cosmogenic nuclide dataset consisting of 123310Be measurements of fluvial sediment samples across the Asian mountain belts is used to constrain the influence of climate,tectonics and topography on earth-surface denudation processes.10Be-derived basin-wide denudation rates were recalculated using a Monte Carlo simulation approach that relied on pixel-by-pixel production *** rates derived span four orders of magnitude,from 7.4±0.7 mm kyr-1（1σ;Central Tibetan Plateau） to 9,646744+777mm kyr-1（1σ;Southern Tibetan Plateau）,with a median of 186 mm *** our results with the traditional basin-wide production rate scaling model using a centroid coordinate and mean elevation,suggests that 96.6%of production rates will be underestimated using the latter method,especially for basins with a large *** bias between both methods reaches as large as 40%,caused by basin hypsometry and the nonlinear scaling of production rate with elevation and *** of the correlations between uniformly recalculated denudation rates and tectonics,climate,topography and rock lithology will facilitate the extrapolation of denudation rates in unknown basins using available *** the perspective of local scales,precipitation coupled with neotectonics-driven landslides is likely the most influential factor in subtropical Taiwan Island,while topography primarily constrains surface denudation rates in the eastern Tibetan Plateau within a narrow range of *** highland regions with glacier coverage,such as the Pamir,central and southern Tibetan Plateau high denudation rates are affected by glaciation,whereas lower precipitation and high erosion base level may limit river incision and evolving relief in the Central Tibetan *** contrast to local-scale findings highlighting a dominant factor constraining denudation rate,our large-scale quantitative analyses across the Asian mountain belts finds that （1） topographic metrics including

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Time-Dependent Zinc Desorption in Some Calcareous Soils of Iran

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Pedosphere 2013年第2期23卷 185-193页

作者： M.BARANIMOTLAGH M.GHOLAMI Department of Soil science College of Water and Soil SciencesGorgan University of Agricultural Sciences and Natural Resources

Desorption of zinc （Zn） from soil is an important factor governing Zn concentration in the soil solution and Zn availability to plants. Batch experiments were performed to study the kinetics of Zn desorption by diethylenetriaminepentaacetic acid （DTPA） from 15 calcareous soil samples taken from Golestan Province in northern Iran. Soils were equilibrated with 0.005 mol L-1 DTPA solutions for 0.25 to 192 h. The results showed that the extraction process consisted of rapid extraction in the first 2 h followed by much slower extraction for the remainder of the experiment. Desorption kinetic data was fitted to pseudo-first-order kinetic model. The experimental data were found to deviate from the straight line of the pseudo-first-order plots after 2 h. The model of two first-order reactions was fitted to the kinetic data and allowed to distinguish two pools for Zn： a labile fraction （Q1）, quickly extracted with a rate constant kl, and a slowly labile fraction （Q2）, more slowly extracted with a rate constant k2. The applicability of pseudo-second-order model in describing the kinetic data of Zn desorntion was also evaluated.

关键词： diethylenetriaminepentmucetic acid kinetic models labile fraction zinc availability

The Effect of Land Use Change on Soil and Water Quality in Northern Iran

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Journal of Mountain science 2012年第6期9卷 798-816页

作者： KHALEDIAN Yones KIANI Farshad EBRAHIMI Sohaila college of Agriculture Department of Soil ScienceGorgan University of Agricultural Sciences and Natural ResourcesGorganIran

Rapid urbanization has led to extensive land-use changes,particularly in developing *** research is aimed to investigate the role of land use and its effect on soil and water quality in Ziarat watershed focusing on four land uses:forest,pasture,cultivated and urban *** samples were taken from a depth of 0-30 cm on each land use and were analyzed by completely randomized split-plot design in two geographical *** showed that bulk density(BD),electrical conductivity(EC),pH,calcium carbonate equivalent(CCE),and soil particle density(DS) of the soil samples in pastures,cultivated and urban areas increased and the mean weight diameter(MWD),soil porosity(F),organic carbons(OC),total nitrogen(TN),exchangeable cations(Ca 2+,Mg 2+,K +,Na +),cation exchange capacity(CEC) and soil microbial respirations(SMR) decreased,respectively in comparison with the forest *** water quality evaluations,sodium adsorption ratio(SAR),electrical conductivity(EC),pH,total dissolved solids(TDS),bicarbonate(HCO 3),chloride(Cl),total hardness(TH),calcium(Ca 2+),potassium(K +),sodium(Na +) and magnesium(Mg 2+) were investigated in two areas:Nahrkhoran and Abgir *** showed that the concentration of TDS,EC and HCO 3 in Naharkhoran station is higher than that in Abgir *** the other hand,the concentration of TDS,EC and HCO 3 in Abgir station are the relatively higher due to its *** hardness had the same trend during the study years except in the last three years;however,TH showed an increase of 25% TH in Naharkhoran for the last two ***,K + and SAR in Naharkhoran station increased by 61%,22%,78% and 56% respectively,in comparison with Abgir *** study demonstrated that the trend of soil degradation and mismanagement of land use may increase the frequency of urban floods and human health problems.

关键词： Deforestation Organic matter loss Soil degradation Soil quality Urbanization Water quality

Barium titanate ceramic inks for continuous ink-jet printing synthesized by mechanical mixing and sol-gel methods

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中国有色金属学会会刊：英文版 2008年第1期18卷 150-154页

作者：周振君杨正方袁启明 college of earth sciences and resources Management Chang'an University Institute of Materials science and Engineering Tianjin University

Ink-jet printing of ceramic thick films is one of low cost on-site ceramic pattern fabrication *** is necessary to investigate the rheological behaviour of ceramic inks and drying behaviour of *** kinds of BaTiO3 ceramic inks were prepared by mechanical mixing and sol-gel methods,*** effect of preparation parameters,such as quantity of polyacrylic acid(PAA)and solid content,on physicochemical and rheologic properties of the ceramic inks was *** results show that they satisfy the requirements of continuous ink-jet *** appearances of printed dots and single printed layers were observed by *** SEM images indicate that dots printed with mixing method ink are in ring shape,and dots printed with sol-gel method ink are in pancake shape,so the printed layer surface with the latter ink is *** causes of these phenomena were discussed.

关键词：陶瓷油墨流变学钛酸钡机械力学

Bending moment resistance of dowel corner joints in case-type furniture under diagonal compression load

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Journal of Forestry Research 2014年第4期25卷 981-984页

作者： Mosayeb Dalvand Ghanbar Ebrahimi Mehdi Tajvidi Mohammad Layeghi Department of Wood and Paper science and Technology College of Natural Resources University of Tehran Karaj Iran

We investigated bending moment resistance under diagonal compression load of comer doweled joints with plywood members. Joint members were made of ll-ply hardwood plywood of 19 mm thickness. Dowels were fabricated of Beech and Hornbeam species. Their diameters （6, 8 and 10 mm） and depths of penetration （9, 13 and 17 ram） in joint members were chosen variables in our experiment. By increasing the connector＇s diameter from 6 to 8 mm, the bending moment resistance under diagonal compressive load was increased, while it decreased when the diameter was increased from 8 to 10 mm. The bending moment re- sistance under diagonal compressive load was increased by increasing the dowel＇s depth of penetration. Joints made with dowels of Beech had higher resistance than dowels of Hornbeam. Highest resisting moment （45.18 N.m） was recorded for joints assembled with 8 mm Beech dowels penetrating 17 mm into joint members Lowest resisting moment （13.35 N.m） was recorded for joints assembled with 6 mm Hornbeam dowels and penetrating 9 mm into joint members.

关键词： bending moment resistance plywood dowel diameter cor-ner joint, case-type furniture

Design of a cationic accelerator enabling ultrafast ion diffusion kinetics in aqueous zinc-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 377-384页

作者： Yawei Xiao Qianqian Gu Haoyu Li Mengyao Li Yude Wang National Center for International Research on Photoelectric and Energy Materials School of Materials and Energy Yunnan University Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island resources School of Chemistry and Chemical Engineering Hainan University college of Chemical Engineering Fuzhou University Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon Technologies Yunnan University

Aqueous zinc-ion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion *** address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn2+diffusion *** employing electrodeposition to coat MoS2on the surface of BaV6O16·3H2O nanowires,the directional built-in electric field generated at the heterointerface acts as a cation accelerator,continuously accelerating Zn2+diffusion into the active *** optimized Zn2+diffusion coefficient in CC@BaV-6O16·3H2O@MoS2(7.5×10～8cm2s-1) surpasses that of most reported V-based ***,MoS2serving as a cathodic armor extends the cycling life of the Zn-CC@BaV6O16·3H2O@MoS2full batteries to over 10000 *** work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices.

关键词： Zinc alloys

Transient chemical-mediated epigenetic modulation confers unrestricted lineage potential on human primed pluripotent stem cells

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science China Life sciences 2025年

作者： Shi Chen Yuanyuan He Lejun Lv Bei Liu Cheng Li Hongkui Deng Jun Xu Department of Cell Biology School of Basic Medical Sciences Peking University Stem Cell Research Center Peking University Health Science Center Peking University Academy of Advanced Interdisciplinary Studies Peking University BeiCell Therapeutics School of Life sciences Center for Bioinformatics Center for Statistical Science Peking University MOE Engineering Research Center of Regenerative Medicine School of Basic Medical Sciences State Key Laboratory of Natural and Biomimetic Drugs Peking University Health Science Center and the MOE Key Laboratory of Cell Proliferation and Differentiation College of Life Sciences Peking-Tsinghua Center for Life Sciences Peking University

Human primed pluripotent stem cells are capable of generating all the embryonic ***,their extraembryonic trophectoderm potentials are *** remains unclear how to expand their developmental potential to trophectoderm *** we show that transient treatment with a cocktail of small molecule epigenetic modulators imparts trophectoderm lineage potentials to human primed pluripotent stem cells while preserving their embryonic *** chemically treated cells can generate trophectoderm-like cells and downstream trophoblast stem cells,diverging into syncytiotrophoblast and extravillous trophoblast *** and CUT&Tag analyses reveal that these induced cells share transcriptional profiles with in vivo trophectoderm and cytotrophoblast,and exhibit reduced H3K27me3 modification at gene loci specific to trophoblast lineages compared with primed pluripotent *** exploration highlighted the critical roles of epigenetic modulators HDAC2,EZH1/2,and KDM5s in the activation of trophoblast lineage *** findings demonstrate that transient epigenetic resetting activates unrestricted lineage potential in human primed pluripotent stem cells,and offer new mechanistic insights into human trophoblast lineage specification and in vitro models for studying placental development and related disorders.

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Encapsulating perovskite quantum dots into 3D COF for visible light-driven CO2 reduction

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science China Chemistry 2025年

作者： Xinxin Wang Yucheng Jin Xiya Yang Qingyu Luan Tianyu Wang Dongdong Qi Kang Wang Jianzhuang Jiang college of Chemistry and Materials science Anhui Normal University Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials Department of Chemistry and Chemical Engineering School of Chemistry and Biological EngineeringUniversity of Science and Technology Beijing

Lead halide perovskite quantum dots（LHP QDs） have been revealed to possess great potential in photocatalytic applications including CO2reduction, which however suffer from poor stability. Herein, a high crystalline hydrazine-linked three-dimensional（3D） covalent organic framework, USTB-17, was fabricated from the reaction between 12-connected building block and 4-connected 3,5,7-tetrakis（4-aldophenyl）-adamantane. Post-modification with Ni2+affords the metallic framework USTB-17（Ni）followed by sequential deposition of the CH3NH2PbI3（MAPbI3） perovskite QDs into its pores, generating the USTB-17（Ni）@MAPbI3composite. Powder X-ray diffraction analysis together with theoretical simulations and transmission electron microscopy discloses the crystalline nature of USTB-17, USTB-17（Ni）, and USTB-17（Ni）@MAPbI3with an unprecedented noninterpenetrated hpt topology. The close contact of QDs inside the COF pores with the Ni catalytic site locating at the pore surface of COF allows a rapid transfer of the photogenerated electrons in QDs to the Ni catalytic sites, enhancing the photocatalytic activity for CO2reduction. This endows USTB-17（Ni）@MAPbI3with efficient photocatalysis performance for photocatalytic CO2reduction with CO generation rate of 365 μmol g-1h-1and CO selectivity up to 96% under visible-light irradiation, 7 times higher than that of USTB-17（Ni）. After four cycles of reactions, the photocatalytic CO generation rate remains almost unchanged, demonstrating its excellent cycle stability.

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Novel Cs-Mg-Al mixed oxide with improved mobility of oxygen species for passive NO_(x)adsorption

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Green Energy & Environment 2024年第10期9卷 1581-1591页

作者： Yimeng Yin Chizhong Wang Lei Qiu Xing Li Feilin Zhao Jie Yu Jinchi Han Huazhen Chang School of Environment and natural resources Renmin University of ChinaBeijing100872China Department of earth System science Tsinghua UniversityBeijing100084China

The development of passive NO_(x)adsorbers with cost-benefit and high NO_(x)storage capacity remains an on-going challenge to after-treatment technologies at lower temperatures associated with cold-start NO_(x)***,Cs_(1)Mg_(3)Al catalyst prepared by sol-gel method was cyclic tested in NO_(x)storage under 5 vol%*** 100°C,the NO_(x)storage capacity(1219 μmol g^(-1))was much higher than that of Pt/BaO/Al_(2)O_(3)(610 μmol g^(-1)).This provided new insights for non-noble metal catalysts in low-temperature passive NO_(x)*** addition of Cs improved the mobility of oxygen species and thus improved the NO_(x)storage *** XRD,XPS,IR spectra and in situ DRIFTs with NH3 probe showed an interaction between CsO_(x)and AlO_(x)sites via oxygen species formed on Cs_(1)Mg_(3)Al *** improved mobility of oxygen species inferred from O2-TPD was consistent with high NO_(x)storage capacity related to enhanced formation of nitrate and additional nitrite species by NO_(x)***,the addition of Mg might improve the stability of Cs_(1)Mg_(3)Al by stabilizing surface active oxygen species in cyclic experiments.

关键词： Passive NO_(x)adsorber Low-temperature NO_(x)storage Cesium O_(x)ygen mobility