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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine Research 2025年第2期10卷 1-15页

作者： Xu Liang Ni-Hui zhang Zhi-Lai zhan Guang-Lu Chang Yan Gao Xia Li Wen-Yuan Gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China Key Laboratory of Modern Chinese Medicine Resources Research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai zhang Pei-Zhi Liu Yan-Bo Li Qi zhang Jun-Zhao xiao Yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang Ye Wang Qian Peng Liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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Sulfolane‑Based Flame‑Retardant Electrolyte for High‑Voltage Sodium‑Ion Batteries

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Nano-Micro Letters 2025年第2期17卷 498-516页

作者： Xuanlong He Jie Peng Qingyun Lin Meng Li Weibin Chen Pei Liu Tao Huang Zhencheng Huang Yuying Liu Jiaojiao Deng Shenghua Ye Xuming Yang Xiangzhong Ren xiaoping Ouyang Jianhong Liu Biwei xiao Jiangtao Hu Qianling zhang Graphene Composite Research Center College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China Center of Electron Microscopy State Key Laboratory of Silicon and Advanced Semiconductor MaterialsSchool of Materials Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China GRINM(Guangdong)Research Institute for Advanced Materials and Technology FoshanGuangdong 528051People’s Republic of China College of Energy Engineering Zhejiang UniversityHangzhouZhejiang 310027People’s Republic of China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105People’s Republic of China Shenzhen Eigen-Equation Graphene Technology Co.Ltd Shenzhen 518000People’s Republic of China

Sodium-ion batteries hold great promise as next-generation energy storage ***,the high instability of the electrode/electrolyte interphase during cycling has seriously hindered the development of *** particular,an unstable cathode–electrolyte interphase(CEI)leads to successive electrolyte side reactions,transition metal leaching and rapid capacity decay,which tends to be exacerbated under high-voltage ***,constructing dense and stable CEIs are crucial for high-performance *** work reports localized high-concentration electrolyte by incorporating a highly oxidation-resistant sulfolane solvent with non-solvent diluent 1H,1H,5H-octafluoropentyl-1,1,2,2-tetrafluoroethyl ether,which exhibited excellent oxidative stability and was able to form thin,dense and homogeneous *** excellent CEI enabled the O3-type layered oxide cathode NaNi_(1/3)Mn_(1/3)Fe_(1/3)O_(2)(NaNMF)to achieve stable cycling,with a capacity retention of 79.48%after 300 cycles at 1 C and 81.15%after 400 cycles at 2 C with a high charging voltage of 4.2 *** addition,its nonflammable nature enhances the safety of *** work provides a viable pathway for the application of sulfolane-based electrolytes on SIBs and the design of next-generation high-voltage electrolytes.

关键词： Sodium-ion batteries Sulfolane-based electrolyte High voltage Layered oxide cathode Flame retardant

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遥感技术在水土保持监测中的应用

工程建设与设计 2018年第6期 265-266页

作者：周湘山秦甦魏凡张磊詹晓敏中国电建集团成都勘测设计研究院有限公司成都611130

近年来,伴随我国持续、大规模、高强度生产建设项目的增多,我国大量的土地被占用,原有植被愈发稀疏,水土流失问题越来越严重,进行水土保持监测成为当务之急。而随着遥感影像资源的日趋丰富以及分类解译处理技术的显著提升,遥感技术凭借... 详细信息

近年来,伴随我国持续、大规模、高强度生产建设项目的增多,我国大量的土地被占用,原有植被愈发稀疏,水土流失问题越来越严重,进行水土保持监测成为当务之急。而随着遥感影像资源的日趋丰富以及分类解译处理技术的显著提升,遥感技术凭借其周期短、速度快、分辨率高等特点,被广泛运用到现代生产建设项目的水土保持监测中去。论文结合遥感技术的相关概况,就其在水土保持监测中的应用状况加以探讨。

关键词：遥感技术水土保持监测

Temperature effect on aerobic denitrification and nitrification

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Journal of Environmental Sciences 2003年第5期15卷 669-673页

作者： XIE Shu guang zhang xiao jian WANG zhan sheng Department of Environmental Science and Technology Tsinghua UniversityBeijing 100084China.

Nitrogen loss without organic removal in biofilter was observed and its possible reason was explained. A lower hydraulic loading could improve aerobic denitrification rate. Aerobic denitrification was seriously affected by low temperature(below 10℃). However, nitrification rate remained high when the temperature dropped from 15℃ to 5℃. It seemed the autotrophic biofilm in BAF could alleviate the adverse effect of low temperature.

关键词： aerobic denitrification nitrification biofilter temperature effect

Multi-type sensor placement and response reconstruction for structural health monitoring of long-span suspension bridges

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Science Bulletin 2016年第4期61卷 313-329页

作者： You-Lin Xu xiao-Hua zhang Songye Zhu Sheng zhan Department of Civil and Environmental Engineering The HongKong Polytechnic UniversityHong KongChina College of Civil Engineering Fuzhou UniversityFuzhou 350108China

This study is devoted to the experimental validation of the multi-type sensor placement and response reconstruction method for structural health monitoring of long-span suspension bridges. The method for multi-type sensor placement and response reconstruction is briefly described. A test bed, comprising of a physical model and an updated finite element （P-E） model of a long-span suspension bridge is also concisely introduced. The proposed method is then applied to the test bed; the equation of motion of the test bed subject to ground motion, the objective function for sensor location optimization, the principles for mode selection and multi-type response reconstruction are established. A numerical study using the updated FE model is performed to select the sensor types, numbers, and locations. Subsequently, with the identified sensor locations and some practical considerations, fiber Bragg grating （FBG） sensors, laser displacement transducers, and accelerometers are installed on the physical bridge model. Finally, experimental investigations are conducted to validate the proposed method. The experimental results show that the reconstructed responses using the measured responses from the limited number of multitype sensors agree well with the actual bridge responses. The proposed method is validated to be feasible and effective for the monitoring of structural behavior of longspan suspension bridges.

关键词： Long-span suspension bridges Structural behavior monitoring Multi-type sensorsMulti-type responses Experimental validation

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長期吸煙者的肺功能研究

镜湖医学 2024年第1期24卷 5-7页

作者：韋名揚彭莉馮芷軒張曉戰澳門鏡湖醫院内科中国

目的瞭解長期吸煙對肺功能的影響,並及早發現慢性阻塞性肺病(chronicobstructive pulmonary disease,COPD)。方法2017年5月~2019年12月,對長期吸煙者進行肺通氣功能檢查,對早期COPD和肺功能異常進行篩查。結果吸煙組199例,非吸煙組73例... 详细信息

目的瞭解長期吸煙對肺功能的影響,並及早發現慢性阻塞性肺病(chronicobstructive pulmonary disease,COPD)。方法2017年5月~2019年12月,對長期吸煙者進行肺通氣功能檢查,對早期COPD和肺功能異常進行篩查。結果吸煙組199例,非吸煙組73例完成肺功能檢查。吸煙組的1秒率(FEV1/FVC)和FEV1%Pred明顯低於非吸煙組。兩組肺功能異常檢出異常率分别為46.2%和15.1%,吸煙組明顯高於非吸煙組(χ^(2)=22.04,P<0.01),其中COPD檢出率36.2%(95%CI:29.5%~42.9%);保留比率受損肺功能(Preserved ratio impaired spirometry,PRISm)檢出率10.1%(95%CI:5.8%~14.2%)。非吸煙組COPD檢出率6.8%(95%CI:1.1%~12.6%);PRISm檢出率8.2%(95%CI:5.2%~14.5%),吸煙組COPD檢出率明顯高於非吸煙組。結論長期吸煙人群中肺功能異常率高、可能COPD檢出率高。肺功能檢查有助於早期發現COPD和肺功能異常人群,為慢性肺病的早期防治提供依據。

关键词：吸煙慢性阻塞性肺病肺功能保留比率受損肺功能

A Microstructural Damage Model toward Simulating the Mullins Effect in Double-Network Hydrogels

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Acta Mechanica Solida Sinica 2022年第4期35卷 682-693页

作者： Lin zhan Rui xiao State Key Laboratory of Fluid Power and Mechatronic System Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceDepartment of Engineering MechanicsZhejiang UniversityHangzhou310027China

The damage models based on the eight-chain model and the affine full-chain network model are not adequate to describe the damage behaviors in double-network(DN)*** overcome this limitation,we propose a combined chain stretch model with new damage flow *** is demonstrated that the new proposed micro-chain stretch is a reduced form of the complete representation for the transversely isotropic tensor *** a result,the damage models based on the eight-chain model and the affine model are incorporated as special *** effects of chain affineness and network entangling are simultaneously involved in the new model,while only one of these two effects can be characterized in either the eight-chain model or the affine *** is further shown that the new model can effectively capture the Mullins features of the DN hydrogels and achieve better agreement with the experimental data than the affine model and the eight-chain model.

关键词： Mullins effect Double-network hydrogel Full-network model Microstructural model

D-band frontier: A new hydrogen evolution reaction activity descriptor of Pt single-atom catalysts

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Journal of Energy Chemistry 2022年第9期31卷 203-209,I0007页

作者： Guangming zhan Yancai Yao Fengjiao Quan Huayu Gu xiao Liu Lizhi zhang Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Institute of Applied & Environmental Chemistry College of Chemistry Central China Normal UniversityWuhan 430079HubeiChina School of Environmental Science and Engineering Shanghai jiao Tong UniversityShanghai 200240China

Hydrogen evolution reaction(HER) is crucial for achieving sustainable development and carbon neutrality, and thus demands efficient catalysts, which necessitates fundamental theory to relieve trial-and-error experiment. To fast screen HER candidates, most studies focus on d-band center(ε)associated with the Gibbs energy of H* adsorption(ΔG). Unfortunately, εrule is not applicable to Pt single atoms on transition metal disulfides(Pt_(1)/TMDs) because of the additional contributions from p states of S atom. Here, we propose a new HER descriptor — d-band frontier(d) by defining the weight of d-band in the energy range of [-1.0 eV, 1.0 eV] of Pt single atoms. This dis exactly correlated with the ΔGof Pt_(1)/TMDs, and thus perfectly describes the structure–activity relationship, as validated by systematical experimental evidences. Moreover, this ddescriptor can be extended to Pt single atoms anchored on other supports(e.g., CN, C, MoO, and CoO), indicating its promising generality.

关键词： Hydrogen evolution reaction Single atoms Transition metal disulfides Descriptor