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Multivariate synergy for heightening ionic HOF robustness and proton conductivity

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Science China Chemistry 2025年

作者： Xiang-Tian Bai Li-Hui Cao Xu-yong chen Jia-Yu Wang Zi-Ye Zhou Shaanxi Key Laboratory of Chemical Additives for Industry College of Chemistry and Chemical EngineeringShaanxi University of Science and Technology

Multicomponent crystalline materials construct more complex and diversified structures with different combinations and modes,which expands the material structure space and application *** this work,we have successfully synthesized two twocomponent ionic hydrogen-bonded organic frameworks （iHOF-32 and iHOF-33） and a three-component iHOF （iHOF-34）.Guanidine hydrochloride which is rich in N and H and has a short chain length strengthens the hydrogen bonding network of iHOF,thereby aiding in the efficient migration of *** rigid architecture of 1,1'-diamino-4,4'-bipyridine diiodide furnishes additional scaffolding for the iHOFs and enhances its robustness under harsh ***-34 accomplishes the combination of the ultra-high proton conductivity of iHOF-32 and the robustness of iHOF-33 by the synergistic interaction among the three components of *** addition,iHOF-34 was fabricated as a composite membrane with a peak proton conductivity of 1.55×10-1S cm-1,which is 3.8 times higher than that of recast Nafion,and has extensive potential in fuel *** self-assembly strategy of multicomponent HOFs opens up new avenues for constructing diverse structures while promising new opportunities for applications in the fields of proton conduction and energy storage.

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Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong yong chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

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柳江盆地髫髻山组凝灰岩地球化学与熔体包裹体水含量特征

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岩矿测试 2025年第1期44卷 88-101页

作者：赵汇珍陈勇涂聪冯艳伟中国石油大学(华东)深层油气全国重点实验室山东青岛266580 中国石油大学(华东)地球科学与技术学院山东青岛266580 中国科学技术大学地球和空间科学学院安徽合肥230026

水作为岩浆体系中最主要的挥发组分,对岩浆的形成和演化有重要的影响,柳江盆地髫髻山组岩浆岩是燕山期火山活动的重要产物,尽管前人对其地球化学特征进行了大量研究,但关于柳江盆地燕山期岩浆中的水含量仍不清楚。熔体包裹体记录了原始... 详细信息

水作为岩浆体系中最主要的挥发组分,对岩浆的形成和演化有重要的影响,柳江盆地髫髻山组岩浆岩是燕山期火山活动的重要产物,尽管前人对其地球化学特征进行了大量研究,但关于柳江盆地燕山期岩浆中的水含量仍不清楚。熔体包裹体记录了原始岩浆信息,是获取岩浆水含量特征的最直接样品。本文基于全岩地球化学分析,利用标准样品建立了显微激光拉曼光谱定量熔体包裹体水含量的标定曲线,并对柳江盆地髫髻山组下部流纹质岩屑-晶屑凝灰岩中石英斑晶内的原生熔体包裹体进行了水含量定量分析。结果表明:髫髻山组下部凝灰岩样品具有富Si、Al、大离子亲石元素富集、高场强元素亏损、轻稀土富集、重稀土亏损、负Eu异常、Sr含量低等特点;熔体包裹体中水含量的定量分析结果为0.99%~4.98%,平均水含量为2.62%,与前人统计的酸性岩浆水含量基本一致。地球化学特征和熔体包裹体水含量分析结果共同揭示了研究区髫髻山期早期为富水酸性岩浆。结合髫髻山期样品的熔体包裹体水含量测定结果及其早期的大规模火山喷发背景,本文认为岩浆中高含水量增强了岩浆系统的喷发动力,是诱发研究区髫髻山期早期大规模火山爆发的有利因素之一。

关键词：柳江盆地髫髻山组凝灰岩熔体包裹体水含量显微激光拉曼光谱法

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Did the reservoir impoundment trigger the Wenchuan earthquake?

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Science China Earth Sciences 2009年第4期52卷 431-433页

作者： yong chen Institute of Geophysics China Earthquake Administration Beijing 100081 China

January 16, 2009 issue of Science magazine published, in its ' News of the Week' section, an article entitled 'A Human Trigger for the Great Quake of Sichuan?'. The article boldly proposed, 'Zipingpu reservoir may hav... 详细信息

关键词： than Did the reservoir impoundment trigger the Wenchuan earthquake

Approximation Algorithms for Graph Partition into Bounded Independent Sets

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Tsinghua Science and Technology 2023年第6期28卷 1063-1071页

作者： Jingwei Xie yong chen An Zhang Guangting chen Department of Mathematics Hangzhou Dianzi UniversityHangzhou 310018China Zhejiang University of Water Resources and Electric Power Hangzhou 310018China

The partition problem of a given graph into three independent sets of minimizing the maximum one is studied in this *** problem is NP-hard,even restricted to bipartite ***,a simple 3/2-approximation algorithm for any 2-colorable graph is *** improved 7/5-approximation algorithm is then designed for a *** theoretical proof of the improved algorithm performance ratio is constructive,thus providing an explicit partition approach for each case according to the cardinality of two color classes.

关键词： graph partition independent set 2-colorable graph approximation algorithm

COMPLEX WIENER-ITO CHAOS DECOMPOSITION REVISITED

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Acta Mathematica Scientia 2019年第3期39卷 797-818页

作者： yong chen yong UU College of Mathematics and Information Science Jiangxi Normal UniversityNanchang 330022China LMAM School of Mathematical Sciences Peking UniversityBeijing 100871China

In this article, some properties of complex Wiener-It? multiple integrals and complex Ornstein-Uhlenbeck operators and semigroups are obtained. Those include Stroock’s formula, Hu-Meyer formula, Clark-Ocone formula, and the hypercontractivity of complex Ornstein-Uhlenbeck semigroups. As an application, several expansions of the fourth moments of complex Wiener-It? multiple integrals are given.

关键词： Complex Hermite polynomials complex Gaussian isonormal processes complex Wiener-Ito Multiple Integrals complex Ornstein-Uhlenbeck operators and semigroups

Randomized Algorithms for Orthogonal Nonnegative Matrix Factorization

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Journal of the Operations Research Society of China 2023年第2期11卷 327-345页

作者： yong-yong chen Fang-Fang Xu College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590ShandongChina

Orthogonal nonnegative matrix factorization(ONMF)is widely used in blind image separation problem,document classification,and human face *** model of ONMF can be efficiently solved by the alternating direction method of multipliers and hierarchical alternating least squares *** the given matrix is huge,the cost of computation and communication is too ***,ONMF becomes challenging in the large-scale *** random projection is an efficient method of dimensionality *** this paper,we apply the random projection to ONMF and propose two randomized *** experiments show that our proposed algorithms perform well on both simulated and real data.

关键词： Orthogonal nonnegative matrix factorization Random projection method Dimensionality reduction Augmented lagrangian method Hierarchical alternating least squares algorithm

PARAMETER ESTIMATION FOR AN ORNSTEIN-UHLENBECK PROCESS DRIVEN BY A GENERAL GAUSSIAN NOISE

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Acta Mathematica Scientia 2021年第2期41卷 573-595页

作者： yong chen Hongjuan ZHOU School of Mathematics and Statistics Jiangxi Normal UniversityNanchang 330022China School of Mathematical and Statistical Sciences Arizona State UniversityArizona 85287USA

In this paper,we consider an inference problem for an Ornstein-Uhlenbeck process driven by a general one-dimensional centered Gaussian process(G_(t))t≥*** second order mixed partial derivative of the covariance function R(t,s)=E[GtGs]can be decomposed into two parts,one of which coincides with that of fractional Brownian motion and the other of which is bounded by(ts)^(β-1)up to a constant *** condition is valid for a class of continuous Gaussian processes that fails to be self-similar or to have stationary increments;some examples of this include the subfractional Brownian motion and the bi-fractional Brownian *** this assumption,we study the parameter estimation for a drift parameter in the Ornstein-Uhlenbeck process driven by the Gaussian noise(G_(t))t≥*** the least squares estimator and the second moment estimator constructed from the continuous observations,we prove the strong consistency and the asympotic normality,and obtain the Berry-Esséen *** proof is based on the inner product's representation of the Hilbert space(h)associated with the Gaussian noise(G_(t))t≥0,and the estimation of the inner product based on the results of the Hilbert space associated with the fractional Brownian motion.

关键词： Fourth moment theorem Ornstein-Uhlenbeck process Gaussian process Malliavin calculus

Pseudo-Effective Vector Bundles with Vanishing First Chern Class on Astheno-Kähler Manifolds

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Chinese Annals of Mathematics,Series B 2023年第6期44卷 819-826页

作者： yong chen Xi ZHANG School of Mathematics and Statistics Nanjing University of Science and TechnologyNanjing 210094China

Let E be a holomophic vector bundle over a compact Astheno-Kähler manifold(M,ω).The authors would prove that E is a numerically flat vector bundle if E is pseudoeffective and the first Chern class c_(1)^(BC)(E)is zero.

关键词： Pseudo-effective Astheno-Kähler Numerically flatness