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STUDY ON THE BEHAVIOR OF RARE EARTH IONS BY PHOSPHORESCENT PROBE METHOD

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Chinese Chemical Letters 1996年第7期7卷 675-678页

作者： Gui Bin MA Fei GAO liang chen and pin yang (Department of Chemistry, Shanxi University, Taiyuan,03006) (Institute of Molecular Science,Shanxi University, Taiyuan, 030006) (Center of Test and Analysis, Shanxi University,Taiyuan,030006) Department of Chemistry Shanxi University Taiyuan 030006 Institute of Molecular Science Shanxi University Taiyuan 030006 Center of Test and Analysis Shanxi University Taiyuan 030006

Utilizing the effect of dioxygen molecules on the luminophors'phosphorescent life, the first attempt to investigate the interaction between the molecules of rare earth coordination compound and cells was carried out. This work has supplied a new reseach method for the studies oftransmembrane process for rare earth ions.

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Increase of chiral sensing ability in host-guest chemistry by magnetic anisotropy

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Science China Chemistry 2024年第8期67卷 2775-2782页

作者： Jia-liang chen Bin Li Feng yang Tiesheng Shi Xun-cheng Su State Key Laboratory of Elemento-organic Chemistry Tianjin Key Laboratory of Biosensing and Molecular RecognitionCollege of ChemistryNankai UniversityTianjin 300071China College of Chemistry Chemical Engineering and Materials ScienceZaozhuang UniversityZaozhuang 277160China

Enantiomeric molecules generally play distinct functions in chemistry,biology,and *** physical and chemical properties of chiral analytes lay difficulty in discrimination and quantification of the *** report herein an efficient approach of increasing the chiral sensing ability ofβ-cyclodextrin(β-CD),a widely used host molecule,in the hostguest chemistry by magnetic anisotropy.A rigid and chiral lanthanide binding tag was attached to theβ-CD to amplify the changes of nuclear magnetic resonance(NMR)signals in the host-guest recognition *** installation of the paramagnetic lanthanide ion inβ-CD greatly enhances the enantiomeric discrimination up to 30-fold in comparison with the diamagneticβ-CD *** addition,the magnitude of the paramagnetic effects is tunable according to the diverse range of paramagnetic strength of the lanthanide *** reported method significantly increases the chiral sensing ability ofβ-CD,which can be applied to other host *** transferred paramagnetic effects,pseudocontact shifts(PCSs)and paramagnetic relaxation enhancements(PREs),from the host to the guest molecules,are valuable structural restraints to determine the absolute stereochemistry of the chiral *** strategy does not need modification of the analytes and is complementary to the reported analytical methods that rely on the functionalization of the chiral analytes.

关键词： chiral recognition nuclear magnetic resonance host-guest chemistry magnetic anisotropy lanthanide ions

Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

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Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： Feng Ren Zhuang-Zhuang liang Ming-Xin Niu chen-yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic *** new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability.

关键词： Polyester Polyether Alternative copolymer Ring-opening polymerization

Unveiling the chemistry behind the electrolytic production of hydrogen peroxide by oxygenated carbon

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Journal of Energy Chemistry 2024年第9期96卷 49-58页

作者： Pan Xiang Kunshang yang Qihao yang yang Gao Wenwen Xu Zhiyi Lu liang chen Zhiming Wang Ziqi Tian Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054SichuanChina Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201ZhejiangChina Institute for Advanced Study Chengdu UniversityChengdu 610106SichuanChina

Oxygenated carbon materials exhibit outstanding electrocatalytic performance in the production of hydrogen peroxide(H2O2)through a two-electron oxygen reduction *** nature of the active functional group and underlying reaction mechanism,however,remain ***,a comprehensive workflow was established to identify the active sites from the numerous possible *** common hydroxyl group at the notched edge demonstrates a key role in the two-electron *** local chemical environment weakens the binding of OOH intermediate to substrate while enhancing interaction with solution,thereby promoting the H_(2)O_(2)*** increasing pH,the intramolecular hydrogen bond between OOH intermediate and hydroxyl decreases,facilitating OOH ***,the rise in selectivity with increasing potential stems from the suppression of the four-electron *** active site was further validated through *** by theoretical understanding,optimal performance was achieved with high selectivity(>95%)and current density(2.06 mA/cm^(2))in experiment.

关键词： First-principles calculation Oxygen reductionreaction Hydrogen peroxide production Fixed-potential method Oxygenated carbon materials

Non-interactive SM2 threshold signature scheme with identifiable abort

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Frontiers of Computer Science 2024年第1期18卷 171-185页

作者： Huiqiang liang Jianhua chen School of Mathematics and Statistics Wuhan UniversityWuhan 430072China

A threshold signature is a special digital signature in which the N-signer share the private key x and can construct a valid signature for any subset of the included t-signer,but less than t-signer cannot obtain any *** the breakthrough achievements of threshold ECDSA signature and threshold Schnorr signature,the existing threshold SM2 signature is still limited to two parties or based on the honest majority setting,there is no more effective solution for the multiparty *** make the SM2 signature have more flexible application scenarios,promote the application of the SM2 signature scheme in the blockchain system and secure cryptocurrency *** paper designs a non-interactive threshold SM2signature schemebasedon partially homomorphic encryption and zero-knowledge *** the last round requires the message input,so make our scheme non-interactive,and the pre-signing process takes 2 rounds of communication to complete after the key *** allow arbitrary threshold t

关键词： SM2 signature secure multi-party computation threshold signature UC-secure dishonest majority

Engineering FeOOH/Ni(OH)_(2) heterostructures on Ni_(3)S_(2)surface to enhance seawater splitting

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Rare Metals 2024年第5期43卷 1989-1998页

作者： chen yang Ya-Dong Li Li-Juan Cao Xi-Long Wang Han-Pu liang Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Sino-Danish College University of Chinese Academy of SciencesBeijing 100049China

The construction of highly stable and efficient electrocatalysts is desirable for seawater splitting but remains challenging due to the high concentration of Cl-in ***,FeOOH/Ni(OH)_(2)heterostructure supported on Ni_(3)S_(2)-covered nickel foam(Fe–Ni/Ni_(3)S_(2)/NF)was fabricated by hydrothermal and etching methods,as well as anodic oxidation *** electronic structure of FeOOH and Ni(OH)_(2)could be modulated after depositing FeOOH nanoparticles on Ni(OH)_(2)nanosheet,which greatly boosted the catalytic *** the catalyst used as an electrode for oxygen evolution reaction(OER),it needed low overpotentials of 266 and 368 m V to achieve current densities of 100 and 800 m A·cm^(-2),respectively,in 1 mol·L^(-1)KOH+seawater *** can operate continuously at 100 m A·cm^(-2)for 400 h without obvious ***,in situ generated SO_(4)^(2-)from inner Ni_(3)S_(2)during electrolysis process would accumulate on the surface of active sites to form passivation layers to repel Cl^(-),which seemed to be responsible for superior *** study not only synthesizes an OER catalyst for highly selective and stable seawater splitting,but also gives a novel approach for industrial hydrogen production.

关键词： Anodic oxidation Heterostructure Oxygen evolution reaction Seawater splitting

A creep model for ultra-deep salt rock considering thermal-mechanical damage under triaxial stress conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 588-596页

作者： Chao liang Jianfeng Liu Jianxiong yang Huining Xu Zhaowei chen Lina Ran College of Water Resource and Hydropower Sichuan UniversityChengdu610065China CNPC Key Laboratory of Oil and Gas Underground Storage Engineering Langfang065007China CNPC Engineering Technology R&D Company Limited Beijing102206China

To investigate the specific creep behavior of ultra-deep buried salt during oil and gas exploitation,a set of triaxial creep experiments was conducted at elevated temperatures with constant axial pressure and unloading confining pressure *** results show that the salt sample deforms more significantly with the increase of applied temperature and deviatoric *** accelerated creep phase is not occurring until the applied temperature reaches 130℃,and higher temperature is beneficial to the occurrence of accelerated *** describe the specific creep behavior,a novel three-dimensional(3D)creep constitutive model is developed that incorporates the thermal and mechanical variables into mechanical ***,the standard particle swarm optimization(SPSO)method is adopted to fit the experimental data,and the sensibility of key model parameters is analyzed to further illustrate the model *** a result,the model can accurately predict the creep behavior of salt under the coupled thermo-mechanical effect in deep-buried *** on the research results,the creep mechanical behavior of wellbore shrinkage is predicted in deep drilling projects crossing salt layer,which has practical implications for deep rock mechanics problems.

关键词： Creep experiments Creep model Thermal and mechanical damage Fractional derivative

Late Cenozoic uplift of the Liupan Mountains:Evidence from the Neogene loess deposits

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Science China Earth Sciences 2024年第5期67卷 1480-1488页

作者： Zhilin HE Yansong QIAO Zhengtang GUO Chaoqin chen Long chen yang FU Ye yang Yanxia liang Xinru LIN Guoqiao XIAO Tao ZHAN Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China University of Chinese Academy of Sciences Beijing 100049China Institute of Ecological Geology Survey and Research of Heilongjiang Province Harbin 150030China School of Geography and Information Engineering China University of GeosciencesWuhan 430078China School of Earth Sciences China University of GeosciencesWuhan 430074China Natural Resources Survey Institute of Heilongjiang Province Harbin 150036China

The Liupan Mountains,one of the important mountain ranges in western China,are located on the boundary between the northeastern Tibetan Plateau and the Ordos *** uplift history of the Liupan Mountains remains *** deposits are good tracers of regional tectonic and geomorphic changes,because loess is sensitive to erosion and the formation and preservation of loess requires relatively flat highlands and relatively stable tectonic *** investigated the distribution of Neogene loess deposits on the western piedmont of the Liupan Mountains and examined a near-continuous loess section(Nanping section)on the piedmont alluvial *** of magnetic susceptibility stratigraphy with the QA-ⅠMiocene loess sequence dates this 56-m section covering the interval from~8.1 to 6.2 *** lower boundary age of this section,together with previously reported Zhuanglang red clay(sand-gravel layers with intercalated loess during~9–8 Ma and near-continuous loess during~8–4.8 Ma)and Chaona red clay(~8.1–2.58 Ma),indicates that the Liupan Mountains were uplifted in the late Miocene(~9–8 Ma)and basically formed by~8 Ma,attesting to no intense mountain building since that *** addition,based on the information from the Zhuanglang core and the QA-Ⅰsection,we infer that sizable parts of the Liupan Mountains were uplifted during the late Oligocene–early Miocene and did not experience intense uplift during~22–9 Ma.

关键词： Liupan Mountains Mountain building Neogene Loess Chinese Loess Plateau Late Miocene Late Oligocene–early Miocene

Drug-loading ZIF-8 for modification of microporous bone scaffold to promote vascularized bone regeneration

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Chinese Chemical Letters 2024年第6期35卷 358-364页

作者： Xin Zhang Junyu chen Xiang Pei Linxin yang liang Wang Luona chen Guangmei yang Xibo Pei Qianbing Wan Jian Wang State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesChengdu 610041China Department of Prosthodontics West China Hospital of StomatologySichuan UniversityChengdu 610041China

Surface modification of microporous bone scaffolds using nanoparticles has been broadly studied in bone tissue *** at improving vascularized bone regeneration(VBR),zeolitic imidazolate framework-8(ZIF-8)was encapsulated with dimethyloxallyl glycine(DMOG)and the drug-carrying nanoparticles(D@Z)could be uniformly coated onto the surface of the bone *** osteogenic and angiogenic actions of D@Z are closely correlated with the amount of slowly released DMOG,and in general,exhibited a favorable ***,the D7.5@Z group,which showed the greatest capacity to induce in vitro osteogenesis-angiogenesis coupling,was utilized for surface modification of the bone *** processes including phosphate-containing compound metabolic process,cell differentiation,cell proliferation and cell motility might contribute to enhanced ability to induce VBR by the coated scaffold and signaling pathways such as Rap1,Ras,phosphatidylinositol 3-kinase/protein kinase B(PI3K-AKT)and vascular endothelial growth factor(VEGF)signaling pathways participated in these ***,as depicted by in vitro real time-polymerase chain reaction(RT-PCR),Western blot(WB)and in vivo cranial bone defect model,the microporous scaffold coated with nano-D7.5@Z greatly promoted *** conclude,nano-D@Z has significant promise for practical application in modification of microporous bone scaffolds to enhance VBR,and DMOG loading quantity has a beneficial influence on D@Z to improve osteogenesis-angiogenesis coupling.

关键词： Drug-loading nanoparticles Surface coating Microporous bone scaffold Vascularization bone regeneration