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Journal of Rare Earths 2024年第7期42卷 1240-1249,I0002页

作者： Ziyao wang haitao Fu Xiufeng Zhan Bo Tong Guofeng Ma h.T.(Bert)hintzen Institute of Innovative Science and Tech.ology Shenyang UniversityShenyang110044China College of Mechanical Engineering Shenyang UniversityShenyang110044China Faculty of Applied Sciences Delft University of Technology2629 JBDelftthe Netherlands

A novel Eu^(2+)-Eu^(3+)co-activated ratiometric thermo-sensitive phosphor was developed and synthesized by solid-state *** valence state of Eu,photoluminescence and thermo-sensitive performance of the phosphor prepared either in ambient air or carbothermally were investigated and *** phosphor shows high sensitivity(Sa=0.0173 K^(-1),S_(r)=0.461%/K)and superior signal discriminability(Δν∼10380 cm^(−1)).The thermo-sensitive performance is subject to the dual effects of different thermo-responses by Eu^(2+)versus Eu^(3+)combined with energy transfer from Eu^(2+)to Eu^(3+),so that the sensitivity of the phosphor in the temperature range presents a non-monotonic *** development of the BaAl_(2)B_(2)o_(7):Eu^(2+),Eu^(3+)phosphor is not only expected to be relevant for application in the field of temperature sensing,but also of reference significance for improving the sensitivity by means of energy transfer between co-activator ions over a wider temperature range of Eu^(2+)-Eu^(3+)co-activated ratiometric thermo-sensitive phosphors.

关键词： Photoluminescence Ratiometric thermo-response Phosphor Eu^(2+)/Eu^(3+) Rare earths

Selective synthesis of the B_(11)h_(14)^(-) and B_(12)h_(12)^(2-) borane derivatives and the general mechanisms of the B-h bond condensation

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Science China Chemistry 2024年第3期67卷 876-881页

作者： Yi Jing Xinghua wang hui han Xin-Ran Liu Xing-Ch.o Yu Xi-Meng Chen Donghui Wei Lai-Sheng wang Xuenian Chen College of Chemistry Green Catalysis CenterZhengzhou UniversityZhengzhou 450001China Sch.ol of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced Energy MaterialsHenan Normal UniversityXinxiang 453007China Department of Chemistry Brown UniversityProvidenceRI 02912USA

Polyhedral boranes are a class of well-known boron molecular clusters with unique physical and chemical properties,and great efforts have been made in the past decades to find more effective synthetic ***,the established synthetic methods suffer from low efficiency and low selectivity because the mechanism of the B-h bond condensation reaction,critical for the synthesis of the polyhedral boranes,is not well *** we report highly selective and efficient synthetic methods of the salts of the tetradecahydridoundecaborate(1-)(B_(11)h^(-)_(14)) and dodecahydrido-dodecaborates(2-)(B_(12)h_(12)^(2-)) anions by employing commercially available and inexpensive starting *** th.oretical and experimental investigations are carried out to elucidate the reaction *** have found that the nature of the B-h bond condensation is the dihydrogen bonding interaction in which the positively charged hydrogens(bridged hydrogens) play a crucial *** current study has not only led to more effective and selective synthetic methods for B_(11)h^(-)_(14) and B_(12)h_(12)^(2-) but also unveiled the nature of the B-h bond condensation and the general formation mechanisms of polyhedral *** finding will facilitate the development of more effective synthetic methods for polyhedral boranes and spur their wide application.

关键词： Boranes polyhedral boranes dihydrogen bond nucleophilicity

Response Evaluation Using Contrast-Enhanced Ultrasound for Unresectable Advanced hepatocellular Carcinoma Treated With Tyrosine Kinase Inhibitors Plus Anti-PD-1 Antibody Therapy

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Possible habitats for Nh_(3),Nh_(2)D,h^(13)CN,hC^(15)N,So,and C^(18)o in the Initial Conditions of high-mass Star Formation

Ultrasound in Medicine and Biology 2024年第1期50卷 142-149页

作者： Zh.o C.-K. Guan X. Pu Y.-Y. Zhou B.-Y. wang L.-F. Sun Y.-K. Yin h.-h. Xia h.-S. wang X. han h. Xu h.-X. Department of Ultrasound Zhongshan Hospital Institute of Ultrasound in Medicine and Engineering Fudan University Shanghai China Shanghai Institute of Medical Imaging Shanghai China Central Laboratory and Department of Medical Ultrasound Sichuan Academy of Medical Sciences Sichuan Provincial People's Hospital University of Electronic Science and Technology of China Chengdu China

objective: The aim of the work described here was to evaluate the role of contrast-enhanced ultrasound (CEUS) in response evaluation for unresectable advanced hepatocellular carcinoma (hCC) treated with tyrosine kinase inhibitors (TKIs) plus anti-programmed cell death protein-1 (PD-1) antibody therapy. Methods: A prospective cohort of consecutive patients with hCC who received combined TKI/anti-PD-1 antibody treatment for unresectable hCC between January 2022 and october 2022 was included in this study. The patients underwent unenhanced ultrasound (US) and CEUS examinations before treatment and at follow-up. Changes in the largest diameters of the target tumor on unenhanced US and the largest diameters of the enhancing target tumors on CEUS were evaluated. Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 with unenhanced US and magnetic resonance imaging/computed tomography (MRI/CT) and modified RECIST (mRECIST) with CEUS and CEMRI/CT were used to assess treatment response. Results: A total of 24 hCC patients (23 men and 1 woman; mean age: 56.5 ± 8.5 y; Barcelona Clinic Liver Cancer stage C, 62.5%; 29 intrahepatic target tumors) were studied. Calculations of degree of necrosis in the target tumors revealed no significant differences between CEUS and CEMRI/CT (44.5 ± 36.2% vs. 45.3 ± 36.8%, p = 0.862). As for the differentiation of responders from non-responders, the agreement between RECIST version 1.1 of unenhanced US and mRECIST-CEUS was poor (κ coefficient = 0.233). Meanwhile, there was a high degree of concordance between mRECIST-CEUS and mRECIST-CEMRI/CT (κ coefficient = 0.812). Conclusion: CEUS proved to be superior to baseline US and is comparable to CEMRI/CT in defining treatment outcome for combined TKI/anti-PD-1 antibody therapy. © 2023 World Federation for Ultrasound in Medicine & Biology

关键词： Anti-angiogenic therapy Anti-PD-1 antibody Contrast-enhanced ultrasound hepatocellular carcinoma

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Research in Astronomy and Astrophysics 2024年第4期24卷 237-252页

作者： Quan-Ling Cui Chuan-Peng Zhang Jun-Jie wang National Astronomical observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Science Qiqihar UniversityQiqihar 161006China Guizhou Radio Astronomical observatory Guizhou UniversityGuiyang 550000China

The initial condition of high-mass star formation is a complex area of study because of the high densities(n_(h_(2))>106cm^(-3))and low temperatures(T_(dust)<18 K)*** such conditions,many molecules become depleted fro... 详细信息

The initial condition of high-mass star formation is a complex area of study because of the high densities(n_(h_(2))>106cm^(-3))and low temperatures(T_(dust)h conditions,many molecules become depleted from the gas phase by freezing out onto dust ***,the N-bearing and deuterated species could remain gaseous under these extreme conditions,suggesting that they may serve as ideal *** this paper,using the Plateau de Bure Interferometer and Very Large Array observations at 1.3 mm,3.5 mm,and 1.3 cm,we investigate the possible habitats for Nh_(3),Nh_(2)D,h^(13)CN,hC^(15)N,So,and C^(18)o in eight massive precluster and protocluster clumps G18.17,G18.21,G23.97N,G23.98,G23.44,G23.97S,G25.38,and *** found that the Nh3cores are in good agreement with the 3.5 mm peak emission,but the Nh_(3)is much more extended than the 3.5 mm emission *** So distributions agree well with the 3.5 mm peaks for the evolved star formation stage,but we did not detect any So emission in the four earliest star formation sources.C^(18)o is a poor tracer in conditions of the cold(■18 K)and dense(■10^(4)cm^(-3))cores,e.g.,the prestellar *** also found that the Nh_(2)D cores are mainly located in the temperature range of 13.0-20.0 K,and the Nh_(2)D lines may be strongly depleted above 20 K.

关键词： galaxies:star formation techniques:interferometric methods:observational

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.Morassuti A.P.L Silva L.A.o.Nunes S.M.Lima L.h.C.Andrade optical and Photothermal Spectroscopy Group(GEoF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Tech.ology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio optical thermometry Judd-ofelt Rare earths

The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang huan Liu Yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional th.ory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(h_(2)o,o_(2),Co_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts th.ough conventional trial and error synthesis and DFT th.ory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional th.ory(DFT)guidance nanomaterials atomically dispersed catalysts

ore Geology,h.o-C Isotopes and 40Ar-39Ar Dating of the Wutonggou Iron Deposit,Eastern Tianshan,NW China:Implications for the Source,Timing,and Genesis of hydrothermal Mineralization in a Sedimentary Iron Deposit

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Journal of Earth Science 2024年第4期35卷 1170-1185页

作者： Chun-Long wang Yi-Tian wang State Key Laboratory of Geological Processes and Mineral Resources Collaborative Innovation Center for Exploration of Strategic Mineral ResourcesSchool of Earth ResourcesChina University of GeosciencesWuhan430074China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing100037China

The Wutonggou iron deposit is located in the well-known iron metallogenic belt in the eastern Tianshan,NW China,and has been regarded as a sedimentary iron *** hydrothermal overprinting could play indispensable roles in the formation of high-grade iron ores in sedimentary iron deposits,previous studies mainly focused on sedimentary-related iron mineralization,while the nature and contribution of hydrothermal fluids are poorly ***,an integrated study of ore geology,h.o-C isotopes and^(40)Ar-^(39)Ar dating,is conducted on the Wutonggou deposit,in order to reveal the features,source,and timing of hydrothermal *** studied deposit includes two mining sections namely the Jianshan and ***δ^(18)o values of early magnetite from the Jianshan section range from+3.0‰to+5.8‰that nearly consistent with classic magmatic magnetite,while increase to 6.3‰-8.0‰in the late *** from the two sections shows comparable h.o isotopic compositions and identical fractionation trends,and is plotted in or periphery to the primary magmatic water *** from the two sections are broadly similar in carbon and oxygen isotopic compositions,and siderite from the Wutonggou section is plotted in the same ***,comparable stable isotopic compositions and evolution trends indicate similar magmatic fluids contributed hydrothermal iron mineralization in the two mining ***,water-rock interactions of varying degrees generated distinct mineralization styles in the Jianshan and Wutonggou sections,and caused the isotopic fractionation in late *** extracted from a hydrothermal siderite ore yielded a^(40)Ar-^(39)Ar plateau age of 299.5±2.0 Ma,indicates the timing of hydrothermal iron mineralization is corresponding to the emplacement of vicinity *** together,the hydrothermal mineralization in the Wutonggou iron deposit was the product of remobilization and upgrading of early sedimentary iron ores,a

关键词： iron deposits h.o-C isotopes 40Ar-39Ar dating sedimentary iron deposits Wutonggou iron deposit eastern Tianshan

Cr-catalyzed allylic C(sp^(3))–h addition to aldehydes enabled by photoinduced ligand-to-metal charge transfer

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Science China Chemistry 2024年第5期67卷 1589-1595页

作者： Xianrong Zeng Feng-hua Zhang Runchen Lai Xiaoyu Lin Zh.obin wang Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake UniversityHangzhou 310030China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Instrumentation and Service Center for Molecular SciencesWestlake UniversityHangzhou 310024China

Photoinduced ligand-to-metal charge transfer(LMCT) has emerged as an effective strategy for synthesizing organic molecules in a sustainable manner. however, the majority of existing reports on selective C(sp^(3))–h bond functionalization via photoinduced LMCT focus on the use of late transition metals or rare-earth metals for radical additions or cross-couplings. In contrast, the utilization of photoinduced LMCT with 3d early transition metals poses a significant challenge. herein, we describe an unprecedented approach to allylic C(sp^(3))–h addition to aldehydes, employing ch.omium(Cr) complexes as catalysts th.ough visible-light-induced LMCT. By investigating the reaction pathway th.ough various mechanistic studies, including radical trapping, kinetic isotope effect(KIE) analysis, and transient absorption spectroscopy, valuable insights have been gained. The proposed mechanism suggests the intermediacy of bromine radicals th.ough homolysis of the Cr–Br bond. Notably, this protocol expands our understanding of the photochemical properties of earth-abundant Cr complexes.

关键词： Cr catalysis photoinduced ligand-to-metal charge transfer hydrogen-atom transfer carbonyl addition

Resistive field generation in intense proton beam interaction with solid targets

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Matter and Radiation at Extremes 2024年第1期9卷 35-43页

作者： W.Q.wang J.J.honrubia Y.Yin X.h.Yang F.Q.Sh.o Department of Physics National University of Defense TechnologyHunanChina ETSI Aeronáutica y del Espacio Universidad Politécnica de MadridMadridSpain Department of Nuclear Science and Tech.ology National University of Defense TechnologyHunanChina

The Brown-Preston-Singleton(BPS)stopping power model is added to our previously developed hybrid code to model ion beam-plasma *** simulations show that both resistive field and ion scattering effects are important for proton beam transport in a solid target,in which they compete with each *** the target is not completely ionized,the self-generated resistive field effect dominates over the ion scattering ***,when the target is completely ionized,this situation is ***,it is found that ohmic heating is important for higher current densities and materials with high *** energy fraction deposited as ohmic heating can be as high as 20%-30%.Typical ion divergences with half-angles of about 5°-10°will modify the proton energy deposition substantially and should be taken into account.

关键词： interaction beam intense

S-scheme regulated Ni_(2)P-NiS/twinned Mn_(0.5)Cd_(0.5)S hetero-homojunctions for efficient photocatalytic h_(2)evolution

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Journal of Materials Science & Tech.ology 2024年第2期169卷 148-157页

作者： Qiqi Zhang Zhen wang Yuhang Song Jun Fan Tao Sun Enzhou Liu Sch.ol of Chemical Engineering/Xi’an Key Laboratory of Special Energy Materials Northwest UniversityXi’an 710069China

Effective bulk phase and surface charge separation is critical for charge utilization during the photo-catalytic energy conversion *** this work,the ternary Ni_(2)P-NiS/twinned Mn_(0.5)Cd_(0.5)S(T-MCS)nanohybrids were successfully constructed via combining Ni_(2)P-NiS with T-MCS solid solution for visible light photocatalytic h_(2)evolution.T-MCS is composed of zinc blende Mn_(0.5)Cd_(0.5)S(ZB-MCS)and wurtzite Mn_(0.5)Cd_(0.5)S(WZ-MCS)and those two alternatively arranged crystal phases endow T-MCS with excellent bulk phase charge separation performance for the slight energy level difference between ZB-MCS and WZ-MCS.S-scheme carriers transfer route between NiS and T-MCS can accelerate the interfacial charge separation and retain the active electrons and holes,meanwhile,co-catalyst Ni_(2)P as electron receiver and proton reduction center can further optimize the h_(2)evolution reaction kinetics based on the surface Schottky barrier *** above-formed homo-heterojunctions can establish multiple charge transfer channels in the bulk phase of T-MCS and interface of T-MCS and Ni_(2)*** the synergistic effect of twinned homojunction,S-scheme heterojunction,and Schottky barrier,the ternary Ni_(2)P-NiS/T-MCS com-posite manifested an h_(2)production rate of 122.5 mmol h^(-1)g^(-1),which was 1.33,1.24,and 2.58 times higher than those of the NiS/T-MCS(92.4 mmol h^(-1)g^(-1)),Ni_(2)P/T-MCS(98.4 mmol h^(-1)g^(-1)),and T-MCS(47.5 mmol h^(-1)g^(-1)),*** work demonstrates a promising strategy to develop efficient sul-fides photocatalyst toward targeted solar-driven h_(2)evolution th.ough homo-heterojunction engineering.

关键词： Photocatalytic h_(2)evolution Twinned Mn_(0.5)Cd_(0.5)S homojunction S-scheme heterojunction Schottky barrier