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Petroleum Science 2024年第2期21卷 1171-1189页

作者： Kun-Peng Zhang Mian Chen chang-jun Zhao Su Wang Yong-Dong Fan State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering in China University of Petroleum Beijing102249China Beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing100871China

A method for in-situ stress measurement via fiber optics was proposed. The method utilizes the relationship between rock mass elastic parameters and in-situ stress. The approach offers the advantage of long-term stress measurements with high spatial resolution and frequency, significantly enhancing the ability to measure in-situ stress. The sensing casing, spirally wrapped with fiber optic, is cemented into the formation to establish a formation sensing nerve. Injecting fluid into the casing generates strain disturbance, establishing the relationship between rock mass properties and treatment ***, an optimization algorithm is established to invert the elastic parameters of formation via fiber optic strains. In the first part of this paper series, we established the theoretical basis for the inverse differential strain analysis method for in-situ stress measurement, which was subsequently verified using an analytical model. This paper is the fundamental basis for the inverse differential strain analysis method.

关键词： In-situ stress Fiber optic Orthotropic elastic Differential evolution ABAQUS

Experimental and first-principles calculation of TiN growth mechanism on CeAlO_(3) surface in steel

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Journal of Iron and Steel Research International 2024年第2期31卷 452-463页

作者： Fei-hu He jun Peng Fang Zhang Yong-bin Wang Hong-tao chang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou014010Inner MongoliaChina

Regular TiN is harmful to the toughness of steel,and its shape and size need to be *** the behavior of TiN precipitation on CeAlO_(3) surfaces is critical for controlling the morphology and formation process of CeAlO_(3)–TiN composite inclusions in the *** results showed that TiN had a square morphology on the CeAlO3 surface,and electron backscatter diffraction phase identification results revealed the orientation relationship between CeAlO_(3) and TiN as follows:(001)_(CeAlO_(3))//(110)_(TiN),(100)_(CeAlO_(3))/(001)_(TiN),and[010]_(CeAlO_(3))/[110]_(TiN).The CeAlO3 crystal structure was studied using the first-principles calculation method,and the adsorption and growth process of TiN on the CeAlO_(3) surface were investigated from the atomic *** calculation results indicate that there is no metallic bonding present in the CeAlO_(3) *** the low-index crystal planes of CeAlO_(3),the(110)planes terminated with O and CeAlO have the highest and lowest surface energies,respectively,with values of 0.373 and 0.051 eV/Å^(2).On the high surface energy plane of CeAlO_(3),the TiN atomic permutation structure is consistent with the arrangement of Ti and N atoms in TiN(100)or(110).For the low surface energy plane of CeAlO_(3),the Ti and N atoms are arranged in a ring-like structure.

关键词： CeAlO_(3)-TiN inclusion Orientation relationship Crystal structure First principle Surface energy

Sustainable Furfural Biomass Feedstocks Electrooxidation toward Value-Added Furoic Acid with Energy-Saving H_(2) Fuel Production Using Pt-Decorated Co_(3)O_(4) Nanospheres

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Energy & Environmental Materials 2024年第2期7卷 350-358页

作者： Talshyn Begildayeνa Jayaraman Theerthagiri seung jun Lee Ahreum Min Gyeong-Ah Kim Siνakumar Manickam Myong Yong Choi Department of Chemistry(BK21 FOUR) Core-Facility Center for Photochemistry&NanomaterialsResearch Institute of Natural SciencesGyeongsang National UniversityJinju 52828South Korea Petroleum and Chemical Engineering Faculty of EngineeringUniversiti Teknologi BruneiJalan Tungku Link GadongBandar Seri Begawan BE1410Brunei Darussalam

Here,furfural oxidation was performed to replace the kinetically sluggish O_(2)evolution reaction(OER).Pt-Co_(3)O_(4)nanospheres were developed via pulsed laser ablation in liquid(PLAL)in a single step for the paired electrocatalysis of an H_(2)evolution reaction(HER)and furfural oxidation reaction(FOR).The FOR afforded a high furfural conversion(44.2%)with a major product of 2-furoic acid after a 2-h electrolysis at 1.55 V versus reversible hydrogen electrode in a 1.0-M KOH/50-mM furfural *** Pt-Co_(3)O_(4)electrode exhibited a small overpotential of 290 mV at 10 mA cm^(-2).As an anode and cathode in an electrolyzer system,the Pt-Co_(3)O_(4)electrocatalyst required only a small applied cell voltage of~1.83 V to deliver 10 mA cm^(-2),compared with that of the pure water electrolyzer(OER||HER,~1.99 V).This study simultaneously realized the integrated production of energy-saving H_(2)fuel at the cathode and 2-furoic acid at the anode.

关键词： biomass conversion electrochemical furfural oxidation overall water splitting Pt-Co_(3)O_(4)electrocatalyst pulsed laser ablation in liquid

A 10-GS/s 8-bit 2× time interleaved hybrid ADC with λ/4 reference T-Line sharing technique

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Science China(Information Sciences) 2024年第8期67卷 351-352页

作者： Zhangming ZHU jun chang Hongzhi LIANG Ruixue DING Shubin LIU Institute of Integrated Circuits Xidian University

With the recent explosion in interactive machine learning and artificial intelligence, the ultra high-speed wireline or optical data links are evaluated as a crucial device that is handling the ever-growing data traffic in high-performance computing environments [1, 2]. In practice, high-order modulation strategies, such as four-level pulse-amplitude modulation(PAM4), enable a significant increase in throughput without raising the baud(Nyquist) rate in transceivers.

关键词： Serpentine

Realizing the excellent oxidation resistance of an environmental barrier coating through aluminum surface modification

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Journal of Advanced Ceramics 2024年第7期13卷 976-986页

作者： Lin Dong Wen-Qi Yang Lin Chen Guan-jun Yang chang-Jiu Li State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Xi’an Aerospace Engine Company Limited in China Aerospace Science and Technology Corporation Xi’an 710065China

The lifetime of Si-based environmental barrier coatings(EBCs)is constrained by thermally grown SiO_(2)oxidelayer(SiO_(2)-TGO),which can cause premature cracking and *** address this issue,a new approach for surfacemodification using aluminum is *** oxidation performance was examined in a 50 vol%H_(2)O-50 vol%O_(2)environment at 1350℃for up to 300 *** results indicate that a dense ytterbium aluminum garnet(YbAG)layer wasformed after modification,decreasing the porosity by 80%.Due to the elimination of fast diffusion channels and the lowoxygen permeability of YbAG,aluminum modification significantly reduced the growth rate of SiO_(2)-TGO by nearly twoorders of ***,its thickness decreased by more than 70%after 300 h of exposure.A diffusioncontrolled oxidation mechanism indicates that the modified dense surface is equivalent to an initial SiO_(2)layer with a specificthickness,causing a shift in the oxidation time and increasing the oxidation *** research provides valuableinsights for designing Si-based EBC with improved lifetimes.

关键词： environmental barrier coating(EBC) oxidation modification diffusion cracking

Tetradentate Pt(Ⅱ)complex as a singlet exciton sensitizing host for highly efficient green fluorescent organic light-emitting diodes

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Science China Materials 2024年第8期67卷 2618-2627页

作者： Unhyeok Jo seung Chan Kim Chan Hee Ryu Kang Mun Lee Jae-Min Kim jun Yeob Lee School of Chemical Engineering Sungkyunkwan University2066Seobu-roJangan-guSuwon-siGyeonggi-do 16419Republic of Korea Department of Chemistry Institute for Molecular Science and Fusion TechnologyKangwon National UniversityChuncheonGangwon 24341Republic of Korea Department of Advanced Materials Engineering Chung-Ang University4726Seodong-daeroDaedeok-myeonAnseong-siGyeonggi-do 17546Republic of Korea SKKU Advanced Institute of Nano Technology Sungkyunkwan University2066Seobu-roJangan-guSuwonGyeonggi 16419Republic of Korea SKKU Institute of Energy Science and Technology Sungkyunkwan University2066Seobu-roJangan-guSuwonGyeonggi 16419Republic of Korea

Efficient green fluorescent organic light-emitting diodes were designed with a phosphorescent metal complex as a singlet exciton sensitizing host(SESH)for achieving high efficiency and low efficiency roll-off through exciton and polaron *** Pt(Ⅱ)complex(Pt-Trz)possessing a tetradentate ligand with a bulky blocking group not only suppresses the severe formation of excimer or dimer itself but also transfers radiative excitons to fluorescent dopant *** SESH assisted fluorescence(SESHF)device with Pt-Trz as the host exhibits the maximum external quantum efficiency of 13.3%and a lower efficiency roll-off compared with exciplex host device which is a general approach for harvesting triplet *** exciton dynamics modeling unravels that the SESHF device effectively utilizes triplet excitons in the host by intersystem crossing and resonance energy transfer from the triplet state of the host to the singlet state of the terminal *** quenching rates of the SESHF device are reduced by 11 times for triplet-triplet annihilation and 1.8 times for tripletpolaron annihilation compared with the exciplex device,which demonstrates that Pt-Trz could be a platform to be used as an efficient host for fluorophores.

关键词： singlet annihilation polaron

Durable dual-state duplex Si-HfO_(2)with excellent oxidation and cracking resistance

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Journal of Advanced Ceramics 2024年第3期13卷 388-401页

作者： Lin Chen Jing-Chuan Luo Wen-Qi Yang chang-Jiu Li Guan-jun Yang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Xi’an Aerospace Engine Company Limited in CASC Xi’an 710065China

The lifetime of Si bond coatings in environmental barrier coatings is constrained by phase-transition-induced cracking of the SiO_(2)*** this study,Si-HfO_(2)dual-state duplex composite materials are proposed to address this issue by partially forming HfSiO_(4)and minimizing the SiO_(2)*** as-prepared composite exhibited a structure comprising discrete HfO_(2)“bricks”embedded in a continuous Si“mortar”,while the oxidized state transformed into discrete HfSiO_(4)“bricks”within continuous thin SiO_(2)“mortars”.The results indicate that continuous thin SiO_(2)contributes to reducing the oxidation rate to a level comparable to that of pure Si,and discrete HfSiO_(4)particles aid in relieving phase transition-induced stress and inhibiting crack propagation,thereby enhancing oxidation and cracking resistance ***,the composite with 20 mol%HfO_(2)and a mean particle size of~500 nm at 1370℃exhibited a service lifetime 10 times greater than that of pure *** research provides valuable insights for designing Si-based bond coatings with improved service lifetime.

关键词： oxidation environmental barrier coatings(EBCs) phase transition cracking bond coatings

CO_(2) hydrogenation to methanol over the copper promoted In_(2)O_(3) catalyst

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Journal of Energy Chemistry 2024年第6期93卷 135-145,I0004页

作者： Rui Zou Chenyang Shen Kaihang Sun Xinbin Ma Zhuoshi Li Maoshuai Li chang-jun Liu School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Collaborative Innovation Center of Chemical Science&Engineering Tianjin UniversityTianjin 300072China

The metal promoted In_(2)O_(3) catalysts for CO_(2) hydrogenation to methanol have attracted wide attention because of their high activity with high methanol ***,there was still no experimental confirmation if copper could be a good promoter for In_(2)O_(3).Herein,the Cu promoted In_(2)O_(3) catalyst was prepared using a deposition-precipitation *** prepared Cu/In_(2)O_(3) catalyst shows significantly higher CO_(2) conversion and space time yield(STY)of methanol,compared to the un-promoted In_(2)O_(3) *** loading of Cu facilitates the activation of both H_(2) and CO_(2) with the interface between the Cu cluster and defective In_(2)O_(3) as the active *** Cu/In_(2)O_(3) catalyst takes the CO hydrogenation pathway for methanol synthesis from CO_(2) *** exhibits a unique size effect on the CO *** temperatures below 250℃,CO adsorption on Cu/In_(2)O_(3) is stronger than that on In_(2)O_(3),causing higher methanol *** increasing temperatu res,the Cu catalyst aggregates,which leads to the formation of weak CO adsorption site and causes a decrease in the methanol *** with other metal promoted In_(2)O_(3) catalysts,it can be concluded that the catalyst with stronger CO adsorption possesses higher methanol selectivity.

关键词： CO_(2)hydrogenation Methanol Cu In_(2)O_(3) CO Selectivity DFT

Intestinal flora: New perspective of type 2 diabetes

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World Journal of Clinical Cases 2024年第11期12卷 1996-1999页

作者： Yan Liu jun chang Li-Ding Bai Department of Gastroenterology Hospital of Integrated Chinese and Western MedicineTianjinTianjin 300100China First Teaching Hospital of Tianjin University of Traditional Chinese Medicine Tianjin 300381China Academy of Traditional Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjin 300193China

Diabetes comprises a group of metabolic diseases characterized by hyperglycemia stemming from various *** diabetes management primarily focuses on blood glucose control,yet it is inherently progressive,necessitating increased reliance on exogenous blood glucose control methods over ***,there is an urgent need to explore novel intervention strategies addressing both diabetes and its *** human intestinal microbiota,often referred to as the"second genome",exhibits significant diversity and plays a pivotal role in insulin resistance,glucose and lipid metabolism,and inflammatory ***,Li and Guo have elucidated the involvement of intestinal flora in the pathogenesis of type 2 diabetes mellitus(T2DM)and proposed a novel therapeutic approach targeting intestinal *** advancement enhances our comprehension of the multifaceted and multi-target regulation of T2DM by intestinal microflora,thereby offering fresh avenues for understanding its pathogenesis and clinical *** letter briefly summarizes the role of intestinal flora in T2DM based on findings from animal experiments and clinical ***,it discusses the potential clinical applications and challenges associated with targeting intestinal flora as therapeutic interventions.

关键词： Microbial metabolites Intestinal flora Probiotics Insulin resistance Type 2 diabetes

Promoting electrocatalytic nitrogen reduction to ammonia via dopant boron on two-dimensional materials

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Rare Metals 2024年第10期43卷 5117-5125页

作者： Ya-Hui Cui Wen-Cheng Ouyang Ai-jun Gao chang-Yuan Yu Li-Peng Zhang State Key Laboratory of Organic-Inorganic Composites College of Chemical EngineeringBeijing University of Chemical Technology College of Materials Science and Engineering Beijing University of Chemical Technology College of Life Science and Technology Beijing University of Chemical Technology

Electrocatalytic nitrogen reduction reaction(NRR) is a key process for producing energy efficient and environment friendly ammonia. Boron-doped two-dimensional materials are highly promising as NRR ***, the interaction between doped boron and matrix materials on NRR catalytic performance is still unclear,which is limiting the development of catalysts containing boron for NRR. Here, NRR on different boron-doped twodimensional(2D) materials was explored by first principle theory. It is found that adsorption energy of intermediate*NNH(E*NNH) can be used as a descriptor to characterize the catalytic activity for NRR. Boron-adsorbed black phosphorus(B-BP) is demonstrated showing excellent NRR catalytic activity and suppressing hydrogen evolution reaction. It is disclosed that the excellent catalytic performance of boron-doped structures comes from a proper quantitatively electron transfer(0.8e) between nitrogen in*NNH and the active site boron atom. This work not only established a descriptor for NRR catalytic activity on B-doped 2D materials, but also screened out a potential NRR catalyst. More importantly, the intrinsic reason and mechanism of high catalytic activity of boron-doped structures were proposed. This work provides a design principle for exploring high-performance NRR electrocatalysts containing boron.

关键词： Boron-doped two-dimensional materials Density functional theory Descriptor Electrocatalytic nitrogen reduction reaction