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Deep-water carbonate dissolution in the northern South China Sea during Marine Isotope Stage 3

Journal of Palaeogeography 2016年第1期5卷 100-107页

作者： Na Wang bao-qi huang He Li School of Earth and Space Sciences Peking University

The production, transportation, deposition, and dissolution of carbonate profoundly form part of the global carbon cycle and affect the amount and distribution of dissolved inorganic carbon （DIC） and alkalinity （ALK）, which drive atmospheric CO2 changes during glacial/interglacial cycles. These processes may provide significant clues for better understanding of the mechanisms that control the global climate system. In this study, we calculate and analyze the foraminiferal dissolution index （FDX） and the fragmentation ratios of planktonic foraminifera for the 60-25 ka B.P. time-span, based on samples from Core 17924 and ODP Site 1144 in the northeastern South China Sea （SCS）, so as to recon- struct the deep-water carbonate dissolution during Marine Isotope Stage 3 （MIS 3）. Our analysis shows that the dissolution of carbonate increases gradually in Core 17924, whereas it remains stable at ODP Site 1144. This difference is caused by the deep-sea carbonate ion concentration （[CO32 ]） that affected the dissolution in Core 17924 where the depth of 3440 m is below the saturation horizon. However, the depth of ODP Site 1144 is 2037 m, which is above the lysocline where the water is always saturated with calcium carbonate; the dissolution is therefore less dependent of chemical changes of the seawater. The combined effect of the productivity and the deep-water chemical evolution may decrease deep-water ICO32-] and accelerate carbonate dissolution. The fall of the sea-level increased the input of DIC and ALK to the deep ocean and deepened the carbonate satu- ration depth, which caused an increase of the deep-water [CO32-]. The elevated ICO32-1 partially neutralized the reduced [CO32-] contributed by remineralization of organic matter and slowdown of thermohaline. These consequently are the fundamental reasons for the difference in dissolution rate between these two sites.

关键词： Carbonate dissolution Planktonic foraminiferaMIS 3South China Sea

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Spatiotemporal patterns of sediment deposition on the northern slope of the South China Sea in the last 150,000 years

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Journal of Palaeogeography 2021年第3期10卷 399-415页

作者： Zhe Hu bao-qi huang Le-Jun Liu Na Wang Key Laboratory of Orogenic Belts and Crustal Evolution MOESchool of Earth and Space SciencesPeking UniversityBeijing 100871China Marine Engineering Environment Center First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061Shandong ProvinceChina School of Urban Planning and Design Shenzhen Graduate SchoolPeking UniversityShenzhen 518055Guangdong ProvinceChina

The source-to-sink system of the northern South China Sea(SCS) has been widely discussed during the past few decades. Sr–Nd isotope, clay minerals and trace elements were extensively used as the proxies of sediment provenance, however, still little is known about the transport processes and controlling mechanisms on detailed spatiotemporal scales due to the limitations of these methods. Here we put forward the new provenance proxies RAKand RKCNbased on major element compositions to study the spatiotemporal changes in sediment provenance since 150 ka mainly from four sites, DLW3101, MD12-3429, ZHS-176 and MD12-3432, which are located on the northern SCS continental slope. Our results show that, spatially, the pathways and intensities of contour currents and gravity flows play important roles in sediment transport. For alongslope processes, the South China Sea Branch of Kuroshio Current(SCSBKC) and the Deep Water Current(DWC) transport sediments from southwestern Taiwan,while the Intermediate Water Current(IWC) can carry sediments from Hainan, the Red River or the Indochina Peninsula. For downslope processes, gravity flows transport materials from the Pearl River delta and shelf to the slope. Moreover, seafloor bathymetry influences sediment transport by altering the pathways of ocean ***, the impacts of sea level and monsoon rainfall fluctuations are always superimposed over the last 150 ka. Sea level fluctuations could significantly change the distance from the Pearl River estuary to the slope, while variations in the East Asian summer monsoon(EASM) rainfall would affect continental erosion rates in the source regions.

关键词： South China Sea Sediment transport Element composition Ocean current Sea level Quaternary

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Identifying the best common factor model via exploratory eactor analysis

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 24-33页

作者： HE bao-hua TANG Rui TAGN qi-yi School of Big Data Fuzhou University of International Studies and TradeFuzhou 350202China School of Mathematics Sun Yat-Sen UniversityGuangzhou 510275China Department of Computer Science University of BathUK Institute of Insect Science Zhejiang UniversityHangzhou 310058China.

Currently,there is no solid criterion for judging the quality of the estimators in factor *** paper presents a new evaluation method for exploratory factor analysis that pinpoints an appropriate number of factors along with the best method for factor *** proposed technique consists of two steps:testing the normality of the residuals from the fitted model via the Shapiro-Wilk test and using an empirical quantified index to judge the quality of the factor *** are presented to demonstrate how the method is implemented and to verify its effectiveness.

关键词： factor analysis Shapiro-Wilk normality residuals

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A novel fused bi-macrocyclic host for sensitive detection of Cr_(2)O_(7)^(2-)based on enrichment effect

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Chinese Chemical Letters 2024年第7期35卷 291-295页

作者： Ting-Ting huang Jin-Fa Chen Juan Liu Tai-bao Wei Hong Yao Bingbing Shi qi Lin Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China Key Laboratory of Environment-Friendly Composite Materials of the State Ethnic Affairs Commission Gansu Provincial Biomass Function Composites Engineering Research CenterCollege of Chemical EngineeringNorthwest Minzu University(Northwest University for Nationalities)Lanzhou 730000China

Improving the highly selective and sensitive binding of chemosensor to target guest is always very *** order to solve this issue,herein,the enrichment effect was introduced into the design of chemosensor molecule.A novel bi-fused-macrocyclic host molecule BPN1 was synthesized by bridging a pillar[5]arene and a naphthalene diimide(NDI)group through hydrogen-bond-rich *** the BPN1,the naphthalimide side ring is outside the cavity of the pillar[5]*** addition,Cr(VI)greatly threat human health and the environment due to its severe toxicity,and it is very important to develop effective chemosensor for sensitive and selective detection of Cr_(2)O_(7)^(2-)or its ion *** this paper,the novel bi-fused-macrocyclic host molecule BPN1 can recognize Cr_(2)O_(7)^(2-)with high selectivity and *** mechanism of BPN1 recognition of Cr_(2)O_(7)^(2-)was studied through experiments and density functional theory(DFT),the results show that BPN1 could supply enrichment effect to bind Cr_(2)O_(7)^(2-)through multiple weak interactions such as hydrogen bonds and anion-π,and achieve highly sensitive and selective detection of Cr_(2)O_(7)^(2-).It is a significant and feasible strategy for improve high selectivity and sensitivity of host to specific objects by using the enrichment effect of fused bi-macrocyclic.

关键词： Pillararene Bi-macrocyclic Detection of Cr_(2)O_(7)^(2−) DFT The enrichment effect

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Advances in the study of auxin early response genes:Aux/IAA,GH3,and SAUR

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The Crop Journal 2024年第4期12卷 964-978页

作者： Dongfang bao Senqiu Chang Xiaodong Li Yanhua qi Key Laboratory of Herbage&Endemic Crop Biology of Ministry of Education Inner Mongolia Key Laboratory of Herbage&Endemic Crop BiotechnologySchool of Life SciencesInner Mongolia UniversityHohhot 010000Inner MongoliaChina

Auxin plays a crucial role in all aspects of plant growth and *** can induce the rapid and efficient expression of some genes,which are named auxin early response genes(AERGs),mainly including the three families:auxin/indole-3-acetic acid(Aux/IAA),Gretchen Hagen 3(GH3),and small auxin-up RNA(SAUR).Aux/IAA encodes the Aux/IAA protein,which is a negative regulator of auxin ***/IAA and auxin response factor(ARF)form a heterodimer and participate in a variety of physiological processes through classical or non-classical auxin signaling *** GH3 encodes auxin amide synthetase,which catalyzes the binding of auxin to acyl-containing small molecule substrates(such as amino acids and jasmonic acid),and regulates plant growth and stresses by regulating auxin *** is a class of small auxin up-regulated *** response to auxin is complex,and the process may occur at the transcriptional,post-transcriptional and protein *** the development of multi-omics,significant progress has been made in the study of Aux/IAA,GH3,and SAUR genes,but there are still many *** review offers insight into the characteristics of Aux/IAA,GH3,and SAUR gene families,and their roles in roots,hypocotyls,leaves,leaf inclinations,flowers,seed development,stress response,and phytohormone crosstalk,and provides clues for future research on phytohormone signaling and the molecular design breeding of crops.

关键词： Auxin Aux/IAA GH3 SAUR Stress

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2:17-type SmCo permanent magnets with controllable remanence temperature coefficients via substitution of heavy rare earth elements

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Rare Metals 2024年第8期43卷 3990-3996页

作者： Jia-Yi huang Shu-Lan Zuo qi Zhang Hong-Yang Dai Lei Yang Jing-Hua Liu Cheng-bao Jiang Key Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and EngineeringBeihang UniversityBeijing 100191China

Permanent magnets that can maintain a constant magnetic flux over a wide temperature range are highly desirable in certain applications such as precision instruments.2:17-type SmCo permanent magnets are promising for such instruments owing to their excellent high-temperature magnetic properties that can be further manipulated byadding heavy rare earth elements (HREs).

关键词： magnets permanent earth

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Cosmological Constraints on Neutrino Masses in Light of JWST Red and Massive Candidate Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 7-12页

作者： Jian-qi Liu Zhi-qi huang Yan Su School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area Zhuhai 519082China

The overabundance of the red and massive candidate galaxies observed by the James Webb Space Telescope(JWST)implies efficient structure formation or large star formation efficiency at high redshift z~*** the scenario of a low or moderate star formation efficiency,because massive neutrinos tend to suppress the growth of structure of the universe,the JWST observation tightens the upper bound of the neutrino *** A cold dark matter cosmology and a star formation efficiency∈[0.05,0.3](flat prior),we perform joint analyses of Planck+JWST and Planck+bao+JWST,and obtain improved constraints∑m_(ν)bao+JWST at 92.7% confidence level.

关键词： (cosmology:)cosmological parameters galaxies:abundances galaxies:formation neutrinos

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An isolated symmetrical 2T2R cell enabling high precision and high density for RRAM-based in-memory computing

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Science China(Information Sciences) 2024年第5期67卷 287-294页

作者： Yaotian LING Zongwei WANG Yuhang YANG Lin bao Shengyu bao qishen WANG Yimao CAI Ru huang School of Integrated Circuits Beijing Advanced Innovation Center for Integrated Circuits Peking University State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

In-memory computing(IMC), leveraging emerging memories, holds significant promise in overcoming memory limitations and improving energy efficiency. However, the prevailing IMC array structure based on serially connected transistors and memory cells(1T1R/2T2R), along with the signed weight mapping scheme, can lead to asymmetrical weight sensing issues(AWS) due to electrical asymmetry within the1T1R/2T2R structure, particularly in highly scaled cells where the transistor's resistance becomes significant. In this paper, we propose and fabricate an electrically symmetric memory cell based on a physically isolated 2T2R structure for IMC. This design aims to enhance the precision and density of RRAM-based IMC arrays. The 2T2R cells are manufactured using the back-end-of-line(BEOL) process of a commercial40 nm technology platform. The feasibility of this design is verified through measured and simulated results,showcasing its capability to address the issue of AWS. Compared to conventional 2T2R cells, this design achieves a considerably smaller transistor footprint without compromising accuracy, while also improving integration density by 42.2%. These innovative memory cell advancements have the potential to further advance high-energy-efficient IMC technology.

关键词： RRAM 2T2R multi-level storage weight asymmetry in-memory computing

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Chinese Clinical Named Entity Recognition Using Multi-Feature Fusion and Multi-Scale Local Context Enhancement

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Computers, Materials & Continua 2024年第8期80卷 2283-2299页

作者： Meijing Li Runqing huang Xianxian qi College of Information Engineering Shanghai Maritime UniversityShanghai200306China

Chinese Clinical Named Entity Recognition(CNER)is a crucial step in extracting medical information and is of great significance in promoting medical ***,CNER poses challenges due to the specificity of clinical terminology,the complexity of Chinese text semantics,and the uncertainty of Chinese entity *** address these issues,we propose an improved CNER model,which is based on multi-feature fusion and multi-scale local context *** model simultaneously fuses multi-feature representations of pinyin,radical,Part of Speech(POS),word boundary with BERT deep contextual representations to enhance the semantic representation of text for more effective entity ***,to address the model’s limitation of focusing just on global features,we incorporate Convolutional Neural Networks(CNNs)with various kernel sizes to capture multi-scale local features of the text and enhance the model’s comprehension of the ***,we integrate the obtained global and local features,and employ multi-head attention mechanism(MHA)extraction to enhance the model’s focus on characters associated with medical entities,hence boosting the model’s *** obtained 92.74%,and 87.80%F1 scores on the two CNER benchmark datasets,CCKS2017 and CCKS2019,*** results demonstrate that our model outperforms the latest models in CNER,showcasing its outstanding overall *** can be seen that the CNER model proposed in this study has an important application value in constructing clinical medical knowledge graph and intelligent Q&A system.

关键词： CNER multi-feature fusion BiLSTM CNN MHA

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Quantifying the Tension between Cosmological Models and JWST Red Candidate Massive Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 1-6页

作者： Jun-Chao Wang Zhi-qi huang Lu huang Jianqi Liu School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area Zhuhai519082China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

We develop a Python tool to estimate the tail distribution of the number of dark matter halos beyond a mass threshold and in a given volume in a *** code is based on the extended Press-Schechter model and is computationally efficient,typically taking a few seconds on a personal laptop for a given set of cosmological *** high efficiency of the code allows a quick estimation of the tension between cosmological models and the red candidate massive galaxies released by the James Webb Space Telescope,as well as scanning the theory space with the Markov Chain Monte Carlo *** an example application,we use the tool to study the cosmological implication of the candidate galaxies presented in Labbéet *** standard Λcold dark matter(ΛCDM)model is well consistent with the data if the star formation efficiency can reach~0.3 at high *** a low star formation efficiency ε~0.1,theΛCDM model is disfavored at~2σ-3σconfidence level.

关键词： (cosmology:)cosmological parameters Galaxy:abundances Galaxy:formation

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