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Tailoring sulfur-doped and nitrogen-defective carbon nitride nanosheets for efficient photo-controlled radical polymerizations

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Science China Chemistry 2024年第7期67卷 2325-2334页

作者： Xue li Meng Kai Xu yuan Huang Tao Cai Key Laboratory of Biomedical Polymers of Ministry of Education College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China Wuhan University Shenzhen Research Institute Shenzhen 518057China

Despite the challenges that remain,the synergistic adjustment of various microstructures and photochemical parameters of graphitic carbon nitride(g-C_(3)N_(4))in photocatalytic reactions holds promises for improving catalytic efficiency and reducing energy ***,sulfur-doped and nitrogen-defective g-C_(3)N_(4)(n-SC_(3)N_(x))nanosheets were designed and elaborately *** resultant n-SC_(3)N_(x)possessed a precisely defined 2D layer structure with extensive porosity and incremental specific surface *** photoinduced electron transfer-reversible addition-fragmentation chain transfer(PET-RAFT)polymerization of vinyl monomers with low dispersity,excellent temporal control and high chain-end fidelity was achieved under mild blue light irradiation in a nondegassed *** to their ultrathin nanostructures with nitrogen defects and sulfur dopants,n-SC_(3)N_(x)was capable of catalyzing RAFT polymerization in aqueous solutions at significantly accelerated rates,which were nearly 8 times faster compared to bulk g-C_(3)N_(4).The ease of separation and efficient reusability in subsequent polymerizations was enabled by the heterogeneous nature of n-SC_(3)N_(x).The appeal of this approach was illustrated by the fact that utilizing a reusable and metal-free photocatalyst in aqueous environments allowed for the synthesis of polymers with molecular weight up to 300 kg mol^(-1) and a dispersity of 1.32.

关键词： graphitic carbon nitride nitrogen defects sulfur dopants PET-RAFT polymerization recyclability

Fractal Characteristics and Main Controlling Factors of High-Quality Tight Sandstone Reservoirs in the Southeastern Ordos Basin

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Journal of Earth Science 2024年第2期35卷 631-641页

作者： Ruilin Hao Wenhui Huang Jiu Bo li yuan Key Laboratory for Marine Reservoir Evolution and Hydrocarbon Abundance Mechanism School of Energy ResourcesChina University of GeosciencesMinistry of EducationBeijing100083China

Due to the complex conditions and strong heterogeneity of tight sandstone reservoirs,the reservoirs should be classified and the controlling factors of physical properties should be *** thin section observations,cathodoluminescence,scanning electron microscopy(SEM),X-ray diffraction(XRD),and high-pressure mercury injection(HPMI)were used to classify and optimize the *** Brooks-Corey model and stepwise regression were used to study the fractal dimension and main controlling factors of the physical properties of the high-quality *** results show that the reservoirs in the study area can be divided into four types,and the high-quality reservoir has the best physical properties and pore-throat *** the high-quality reservoir,the homogeneity of transitional pores was the best,followed by that of micropores,and the worst was *** porosity was controlled by depth and *** model with standardized coefficients is y=12.454−0.778×(Depth)+0.395×(Kaolinite).The permeability was controlled by depth,illite/montmorillonite,and siliceous cement,and the model with standardized coefficients is y=1.689−0.683×(Depth)−0.395×(Illite/Montmorillonite)−0.337×(Siliceous Cement).The pore-throat evolutionary model shows that the early-middle diagenetic period was when the reservoir physical properties were at their best,and the kaolinite intercrystalline pores and residual intergranular pores were the most important.

关键词： fractal dimension main controlling factors stepwise regression high-quality tight sandstone reservoir Ordos Basin petroleum geolgoy

Visual observation of photonic Floquet–Bloch oscillations

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light(Science & Applications) 2024年第5期13卷 921-929页

作者： Zhen Zhang yuan li Xiankai Sun Xuewen Shu Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhanHubei 430074China Department of Electronic Engineering The Chinese University of Hong KongShatinNew TerritoriesHong Kong SARChina

Bloch oscillations(BOs),an important transport phenomenon,have been studied extensively in static systems but remain mysterious in Floquet ***,by harnessing notions from photonic analogy,we propose a generalization of the existing BOs in photonic Floquet lattices,namely the“photonic Floquet–Bloch oscillations”,which refer to rescaled photonic Bloch oscillations with a period of extended least common multiple of the modulation period and the Bloch oscillation ***,we report the first visual observation of such photonic Floquet–Bloch oscillations(FBOs)by employing waveguide fluorescence *** significantly,the FBOs surpass the existing BOs in Floquet systems and exhibit exotic properties on their own,including fractal spectrum and fractional Floquet *** new transport mechanism offers an intriguing method of wave manipulation that may contribute to rapidly developing fields in photonics,condensed matter physics,and quantum physics.

关键词： Bloch analogy generalization

Non-Targeted Metabolomics Reveals the Metabolic Alterations in Response to Artificial Selective Breeding in the Fast-Growing Strains of Pacific Oyster

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Journal of Ocean University of China 2024年第2期23卷 518-528页

作者： HU Boyang TIAN yuan liU Shikai li Qi Key Laboratory of Mariculture Ministry of EducationOcean University of ChinaQingdao 266003China Laboratory for Marine Fisheries Science and Food Production Processes Laoshan LaboratoryQingdao 266237China

Pacific oyster(Crassostrea gigas)is one of the most important mollusks cultured all around the *** breeding programs of Pacific oysters in China is initiated since 2006 and developed the genetically improved strain with fast-growing ***,little is known about the metabolic signatures of the fast-growing *** the present study,the non-targeted metabolomics was performed to analyze the metabolic signatures of adductor muscle tissue in one-year old Pacific oysters from fast-growing strain and the wild population.A total of 7767 and 10174 valid peaks were extracted and quantified in ESI^(+)and ESI^(−)modes,resulting in 399 and 381 annotated metabolites,*** and OPLS-DA revealed that considerable separation among samples from fastgrowing strain and wild population,suggesting the differences in metabolic ***,81 significantly different metabolites(SDMs)were identified in the comparisons between fast-growing strain and wild population,based on the strict *** was found that there were highly correlation and conserved coordination among these *** enrichment analysis indicated that the SDMs were tightly related to pantothenate and CoA biosynthesis,steroid hormone biosynthesis,riboflavin metabolism,and arginine and proline *** them,the CoA biosynthesis and metabolism,affected by pantetheine and pantothenic acid,might be important for the growth of Pacific oysters under artificial selective *** study provides the comprehensive views of metabolic signatures in response to artificially selective breeding,and is helpful to better understand the molecular mechanism of fastgrowing traits in Pacific oysters.

关键词： metabolic signature Pacific oyster artificial selection fast-growing trait

Sigmatropic rearrangements of B(MIDA)-propargylic alcohols towards the diverse synthesis of α-functionalized organoborons

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Science China Chemistry 2024年第2期67卷 568-575页

作者： Jiasheng Qian li-Cai liu Zhi-Hao Chen yuan liu Yin li Qingjiang li Honggen Wang Guangdong Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-Sen UniversityGuangzhou510006China

α-Functionalized organoborons are useful building blocks and key structural elements in functional *** previous synthesis relied on the famous Matteson reaction or the late-stage borylative modification of alkynes or ***,the synthetic transformation of borylated building blocks offers another useful strategy and is currently actively *** report herein that B(MIDA)-propargylic alcohols(BPAs) are a useful type of borylated building *** two complementary functional group handles(alkyne and hydroxyl) in close proximity,the redox-neutral [3,3] and [2,3] sigmatropic rearrangements of BPAs allow the efficient synthesis of several types of α-functionalized boronates,including α,β-unsaturated acylborons,α-S/P-substituted allenylborons,boryl-substituted thiazoles and a borylated α,β-unsaturated hydrazine,some of which are otherwise challenging targets using other synthetic methods.

关键词： organoboron diverse synthesis sigmatropic rearrangement heteroarene amide

A Dietary Source of High Level of Fluoroquinolone Tolerance in mcr-Carrying Gram-Negative Bacteria

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Research 2024年第3期2023卷 105-121页

作者： Tianqi Xu Dan Fang Fulei li Zhiqiang Wang yuan liu Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses College of Veterinary MedicineYangzhou UniversityYangzhou 225009China. Joint International Research Laboratory of Agriculture and Agri-Product Safety the Ministry of Education of ChinaYangzhou UniversityYangzhou 225009China. Institute of Comparative Medicine Yangzhou UniversityYangzhou 225009China.

The emergence of antibiotic tolerance,characterized by the prolonged survival of bacteria following antibiotic exposure,in natural bacterial populations,especially in pathogens carrying antibiotic resistance genes,has been an increasing threat to public ***,the major causes contributing to the formation of antibiotic tolerance and underlying molecular mechanisms are yet poorly ***,we show that potassium sorbate(PS),a widely used food additive,triggers a high level of fluoroquinolone tolerance in bacteria carrying mobile colistin resistance gene *** studies demonstrate that PS treatment results in the accumulation of intracellular fumarate,which activates bacterial two-component system and decreases the expression level of outer membrane protein OmpF,thereby reducing the uptake of *** addition,the supplementation of PS inhibits aerobic respiration,reduces reactive oxygen species production and alleviates DNA damage caused by bactericidal ***,we demonstrate that succinate,an intermediate product of the tricarboxylic acid cycle,overcomes PS-mediated ciprofloxacin *** multiple animal models,ciprofloxacin treatment displays failure outcomes in PS preadministrated animals,including comparable survival and bacterial loads with the vehicle *** together,our works offer novel mechanistic insights into the development of antibiotic tolerance and uncover potential risks associated with PS use.

关键词： overcome thereby additive

Experimental crushing behavior and energy absorption of angular gradient honeycomb structures under quasi-static and dynamic compression

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Defence Technology（防务技术） 2024年第6期36卷 47-63页

作者： Jiachen li Yuchen Wei Hao Wu Xingyu Shen Mengqi yuan State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Institute of Occupational Health China Academy of Safety Science and TechnologyBeijing 100012China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

The high variability of shock in terrorist attacks poses a threat to people's lives and properties,necessitating the development of more effective protective *** study focuses on the angle gradient and proposes four different configurations of concave hexagonal honeycomb *** structures'macroscopic deformation behavior,stress-strain relationship,and energy dissipation characteristics are evaluated through quasi-static compression and Hopkinson pressure bar impact *** study reveals that,under varying strain rates,the structures deform starting from the weak layer and exhibit significant interlayer ***,interlayer shear slip becomes more pronounced with increasing strain *** terms of quasi-static compression,symmetric gradient structures demonstrate superior energy absorption,particularly the symmetric negative gradient structure(SNG-SMS)with a specific energy absorption of 13.77 J/cm~*** dynamic impact,unidirectional gradient structures exhibit exceptional energy absorption,particularly the unidirectional positive gradient honeycomb structure(UPG-SML)with outstanding mechanical *** angle gradient design plays a crucial role in determining the structure's stability and deformation mode during *** interlayer separations result in a more pronounced negative Poisson's ratio effect and enhance the structure's energy absorption *** findings provide a foundation for the rational design and selection of seismic protection structures in different strain rate impact environments.

关键词： Negative Poisson's ratio Gradient honeycomb structure Quasi-static compression Dynamic impact Titanium alloy

A brief review of tribological properties for black phosphorus

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Friction 2024年第5期12卷 823-844页

作者： Fanfan LV Wei WANG Jinjin li yuan GAO Kuaishe WANG College of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055China State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing10084China

Black phosphorus (BP) is a new class of two-dimensional (2D) layered material, which shows the unanticipated characteristics in many aspects including electronics, transistors, sensors, energy storage, batteries, photocatalysis, and other applications due to its high charge carrier mobility, tunable direct bandgap, and unique in-plane anisotropic structure. In addition, BP has drawn tremendous attention in the field of tribology due to the low shear strength, the layered structure, and the weak connected force between the layers by van der Waals interaction. In recent years, many significant progresses have been made in experimental studies on BP materials as solid lubricants or lubrication additives. This work offers a review of researching regarding the tribological properties of BP. Moreover, the lubrication mechanisms of BP as the lubrication additive including the formation of the tribo-film, micro-bearing effect, and self-repair performance are also summarized. Finally, the current challenges and prospects of BP material as lubricant are proposed.

关键词： black phosphorus(BP) two-dimensional(2D)layered material lubrication additives tribological mechanisms

Electrolyte-gated SrCoO_(x) FET sensor for highly sensitive detecting pH in extreme alkalinity solution

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Nano Research 2024年第4期17卷 3079-3086页

作者： Han Zhou Gaocan Qi Wenbin li Yuhang Wang Zhihao yuan School of Materials Science and Engineering Tianjin Key Lab of Photoelectric Materials&Devicesand Key Laboratory of Display Materials and Photoelectric Devices(Ministry of Education)Tianjin University of TechnologyTianjin 300384China

The pH monitoring is significantly important in chemical industry,biological process,and pollution ***,it remains a great challenge to measure pH in extreme alkalinity ***,we employ an electrolyte-gated field-effect-transistor(FET)strategy using non-stoichiometric SrCoO_(x) with rich oxygen-vacancy defects as channel materials for detecting extreme *** corresponding channel can provide effective oxygen-ion-migration sites for reversible transformation of OH-↔O_(2)-+H^(+)driven by electric *** resultant electrolyte-gated FET sensor exhibits a sensitive linear response to high concentrations of alkaline solution,1–20 ***,the sensor has the ability to directly indicate the pH values ranging from 14.0 to 17.0 in consideration of ion-activity coefficient *** work offers a great possibility for directly detecting base concentration as well as pH values in extreme alkaline solutions.

关键词： field-effect-transistor(FET) pH sensor extreme alkaline solution SrCoO_(x) oxygen-ion migration