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Four-birds-with-one-stone:A multifunctional Ti-based material for solar-driven water evaporation

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Nano Research 2024年第5期17卷 4498-4506页

作者： Yannan Li Yaning Sun Dan Zhang Yu Xue jie.wang Nan Zhang jun wang Jiangwei Zhang Yan Zhao jun-jie Liu School of Physical Science and Technology College of Energy Materials and ChemistryInner Mongolia UniversityHohhot 010021China

Sustainable,environmentally friendly and low-energy desalination materials have important research value for the increasing demand of freshwater year by ***,it is a huge challenge to maintain high heat energy transfer efficiency without reducing the heat conversion capacity of specific solar photothermal conversion ***,their efficiency and durability are greatly limited by the problems of seawater corrosion,oil,and bacteria *** now,no related work has been reported to solve all the aforementioned problems via a simple four-birds-with-one-stone ***,a class of multifunctional porous photothermal silver(Ag)modified Ti foams(Tf-TA/Ag series materials)is prepared for the development of advanced solar water evaporation devices,and provides alternative materials for alleviating freshwater crisis and treating *** oil contact angle(OCA)changes from 41°to 180°,which significantly reduces the adhesion of *** addition,Tf-TA2/Ag sample also shows an excellent and sustained antibacterial effect,which maintains above 99.9%of antibacterial rate after repeated 5 *** surface temperature of the Tf-TA2/Ag sample reaches 52.5℃ after simulated sun irradiation for 20 min,which is significantly higher than that of the contact groups(water:36.4℃,Ti foam:38.2℃ and Tf-TA2:40.9℃).The capacity of seawater evaporation and salt removal is enhanced due to the excellent photothermal properties,low reflectance,and uniform heat dissipation *** water production efficiency of Tf-TA2/Ag sample is 1.41 kg·m^(-2)·h^(-1) in artificial seawater and 0.76 kg·m^(-2)·h^(-1) in oily sewage under simulated sun ***,the hydrophilic and oleophobic properties of Tf-TA2/Ag are critical to extracting water from oil/water mixture in diverse water ***,this four-birds-with-one-stone approach provides a new perspective for the improvement of solar seawater desalination performance.

关键词： four-birds-with-one-stone photothermal material antibacterial material antifouling property

SO_(2)-Insertion induced enantioselective oxysulfonylation to access β-chiral sulfones with quaternary carbon stereocenters

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Science China Chemistry 2024年第3期67卷 908-913页

作者： jun Zhang Xuefeng wang Peiqi wang Jiayuan Fang Shaoyu Li jie Wu School of Pharmaceutical and Chemical Engineering&Institute for Advanced Studies Taizhou UniversityShanghai 200438China Department of Chemistry Fudan UniversityShanghai 200438China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

β-Chiral sulfones are structural motifs widely found in natural products and bioactive molecules, while also serving as important intermediates for the synthesis of valuable chiral scaffolds. In contrast to the rapid growth of sulfur dioxide insertion chemistry over the last decade, enantioselective catalytic variants for accessing β-chiral sulfones, especially those bearing a quaternary carbon stereocenter, remain rare. Herein, we report an enantioselective copper/bisoxazoline catalyzed oxysulfonylation of alkenes to yield isoxazolinyl-containing β-chiral sulfones bearing quaternary carbon stereocenters with moderate to excellent yields and up to 96:4 er. The advantage and irreplaceability of this sulfur dioxide insertion catalytic system have been demonstrated by achieving transformations clearly unavailable with the previously reported sulfonyl chloride system. Additionally,the recoverability of the new-developed bisoxazoline ligand L9 and its reusability without any erosion of the catalytic activity and enantioselectivity further demonstrate the usefulness of the protocol.

关键词： β-chiral sulfones sulfur dioxide insertion oxysulfonylation copper catalysis enantioselectivity

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

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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 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

Multiwavelength Observations of the Infrared Dust Bubble N75 and its Surroundings

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Research in Astronomy and Astrophysics 2024年第4期24卷 262-270页

Infrared dust bubbles play an important role in the study of star formation and the evolution of the interstellar *** this work,we study the infrared dust bubble N75 and the infrared dark cloud G38.93 mainly using the tracers C^(18)O,HCO^(+),HNC and N_(2)H^(+)observed by the 30 m IRAM *** also study the targets using data from large-scale surveys:GLIMPSE,MIPSGAL,GRS,NRAO VLA Sky Survey and Bolocam Galactic Plane *** found that the C^(18)O emission is morphologically similar to the Spitzer IRAC 8.0μm ***1.1 mm cold dust emission of G38.93 shows an elongated structure from southwest to *** ionized gas from G38.93 is surrounded by polycyclic aromatic hydrocarbon emission,which may be excited by radiation from *** found that the identified young stellar objects tend to cluster around G38.93 and are mostly in class II with several class I cases distributed around N75,but no class II *** also found evidence of expanding feedback,which could have triggered star formation.

关键词： ISM:bubbles infrared:ISM galaxies:star formation

Construct a 3D microsphere of HMX/B/Al/PTFE to obtain the high energy and combustion reactivity

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Defence Technology（防务技术） 2024年第2期32卷 45-54页

作者： Jian wang jie Chen Yaofeng Mao Yongjun Deng Wei Cao Fude Nie jun wang Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621999PR China Shock and Vibration of Engineering Materials and Structures Key Lab of Sichuan Province Mianyang 621010PR China

Metal(aluminum and boron)based energetic materials have been wildly applied in various fields including aerospace,explosives and micro-devices due to their high energy ***,the low combustion efficiency and reactivity of metal fuels,especially boron(B),severely limit their practical ***,multi-component 3D microspheres of HMX/B/Al/PTFE(HBA)have been designed and successfully prepared by emulsion and solvent evaporation method to achieve superior energy and combustion *** reactivity and energy output of HBA are systematically measured by ignitionburning test,constant-volume explosion vessel system and bomb *** to the increased interfacial contact and reaction area,HBA shows higher flame propagation rate,faster pressurization rate and larger combustion heat of 29.95 cm/s,1077 kPa/s,and 6164.43 J/g,which is 1.5 times,3.5 times,and 1.03 times of the physical mixed counterpart(HBA-P).Meanwhile,HBA also shows enhanced energy output and reactivity than 3D microspheres of HMX/B/PTFE(HB)resulting from the high reactivity of *** reaction mechanism of 3D microspheres is comprehensively investigated through combustion emission spectral and thermal analysis(TG-DSC-MS).The superior reactivity and energy of HBA originate from the surface etching of fluorine to the inert shell(Al_(2)O_(3) and B_(2)O_(3))and the initiation effect of Al to *** work offers a promising approach to design and prepare high-performance energetic materials for the practical applications.

关键词： HMX/B/Al/PTFE 3D microspheres Surface etching Reaction mechanism

Effect of electrical parameters and slag system on macrostructure of electroslag ingot

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China Foundry 2024年第1期21卷 44-50页

作者： Bing-jie.wang Yu wang Meng-jun wang Lei Zhao Li-zhong Chang Xiao-fang Shi School of Metallurgy engineering Anhui University of TechnologyMa'anshan 243002AnhuiChina

To investigate the influence of electric parameters and slag system on the solidification quality of electroslag ingot during electroslag remelting,different power supply modes,current strengths and remelting slag systems were used to conduct electroslag remelting experiments on 304L austenitic stainless steel,and the macrostructure of electroslag ingots was *** results indicate that the depth of the metal pool decreases with the reduction of remelting frequency in the low frequency power supply *** effects of different power supply modes,such as low-frequency,direct current straight polarity(DCSP),and direct current reverse polarity(DCRP),on reducing the depth of the metal pool increase in that *** reducing the remelting current strength in the same power supply mode,the depth of metal pool is *** compared to the binary slag system of 70%CaF2+30%Al2O3,the ternary slag system of 60%CaF2+20%Al2O3+20%CaO is more effective in reducing the depth of the metal pool during *** the 60%CaF2+20%Al2O3+20%CaO ternary slag system results in a shallower and flatter metal pool,with columnar crystal growth occurring closer to the axial *** effect is observed for both low frequency and direct current(DC)power supply modes.

关键词： electroslag remelting frequency slag system solidification quality

Sequential enantioselective Ugi-4CR/post-Ugi transformation strategy:a precise construction of structurally diverse azaspiro polycyclic scaffolds

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Science China Chemistry 2024年第2期67卷 576-586页

作者： Xiao-Bao Wu jun-Xiu Shi Yi-Ming Ou Hua-jie Jiang Yi-jun Fang Qi-Ming wang Quan Gao jie Yu Department of Applied Chemistry Anhui Province Engineering Laboratory for Green Pesticide Development and ApplicationAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Agricultural UniversityHefei230036China

A privileged strategy has been developed for the precise construction of enantioenriched azaspiro polycyclic *** diverse azaspiro polycycles bearing multiple contiguous stereocenters are obtained with excellent results(up to 99:1 e.r.,>95:5 d.r.) via sequential enantioselective four-component Ugi reactions/post-Ugi transformations with substrates containing prerequisite functional groups in the presence of anionic stereogenic-at-cobalt(Ⅲ) complexes.

关键词： asymmetric catalysis post-Ugi transformation anionic stereogenic-at-cobalt(Ⅲ)complex azaspiro polycyclic scaffold one-pot synthesis

How interfacial electron-donating defects influence the structure and charge of gold nanoparticles on TiO_(2)support

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Nano Research 2024年第7期17卷 5965-5974页

作者： Guang-jie Xia Yu Fu Wei Cao jun Li Yang-Gang wang Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and TechnologyShenzhen 518055China School of Physical Sciences Great Bay UniversityDongguan 523000China Department of Chemistry Tsinghua UniversityBeijing 100084China

The reduction degree of TiO_(2)support is critical to the performances of metal *** many previous theoretical calculations,only the bridge oxygen vacancy(Ov)was considered as the electron-donating defect on reduced rutile TiO_(2)(r-TiO_(2−x))***,titanium adatoms(Tiad.),oxidized titanium islands(***),and acid hydroxyls(ObrH)also exist at the metal/support *** conducting density functional theory(DFT)calculations and ab initio molecular dynamics(AIMD)simulations,we compared r-TiO_(2−x)surfaces with Ov,Tiad.,***,and ObrH sites loaded with Au nanoparticles(NPs).The results showed the Au NPs were oxygen-phobic but titanium-philic,resulting in wetting of Ov and *** short contact with *** and *** Bader charges of Au NPs(QM)showed a good linear relationship with the ideal number of donating electrons(Ne)from the defective sites(QM=−KeNe+QM,S),demonstrating the intrinsic electron allocation at the *** Ov,Tiad.,and *** exhibited similar slopes(Ke),relatively steeper than that of *** means in the scope of Au NP charge state,the *** *** have a close electron-donating ability with Ov,but the ObrH donates relatively fewer *** linear relationship can be extended approximately to other *** higher the metal work function,the steeper the Ke for easier electron donation from defective *** stronger the metal oxygen affinity,the more positive the intercept(QM,S).That explains the easy generation of metallic or negative Pt and Au NPs on r-TiO_(2−x),but hard for Cu and Zn in *** provides theoretical guidance for regulating the charge of metal NPs over TiO_(2−x)supports.

关键词： metal-support interaction titanium oxide oxygen vacancy surface hydroxyl titanium adatom

Determination of ice jam thickness—A new approach

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Journal of Hydrodynamics 2024年第3期36卷 570-581页

作者： jun wang Lian-sheng Sang Fei-hu Song Tie-jie Cheng Jueyi Sui School of Civil and Water Engineering Hefei University of TechnologyHefei230009China School of Engineering University of Northern British ColumbiaPrince GeorgeCanada

In winter,rivers in cold regions often experience flood disasters resulted from ice jams or ice *** of the variation of ice jam thickness and water level during an ice jammed period are not only a practical need for ice prevention to avoid disaster and plan water resource,but also essential for the development of any mathematical model for predicting the evolution of ice *** far,some equations based on the energy equation have been proposed to describe the relationship between ice jam thickness and water ***,in the derivation of these equations,the local head loss coefficient at the ice jam head and the riverbed slope factor were ***,those reported equations cannot be used to preciously describe the flow energy equation with ice jams and accurately calculate the ice jam thickness and water *** the present study,a more comprehensive theoretical model for hydraulic calculation of ice jam thickness has been derived by considering important and essential factors including riverbed slope and local head loss coefficient at the ice jam ***,based on the data collected from laboratory experiments of ice jam accumulation,the local head loss coefficient at the ice jam head has been calculated,and the empirical equation for calculating the local head loss coefficient has been established by considering flow Froude number and the ratio of ice discharge to flow *** results of this study not only provide a new reference for calculating ice jam thickness and water level,but also present a theoretical basis for accurate CFD simulation of ice jams.

关键词： Energy equation ice jam thickness local head loss coefficient ice jam head riverbed slope