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Petrol.um 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 Petrol.um Resources and Prospecting China University of PetroleumBeijing102249China MOE Key laboratory of Petrol.um Engineering in China university of Petrol.um 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

Childhood malaria in the Niger delta area of Nigeria:mothers/care givers'perception,definition and treatment practices

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Asian Pacific Journal of Tropical Medicine 2009年第3期2卷 52-58页

作者： Idogun E.Sylvester Airauhi l.u Department of Chemical Pathology University of Benin Teaching HospitalBenin City Department of Medical Microbiology Biology University of Benin Teaching HospitalBenin City

Objective:The objective of the study was to evaluate mothers/care givers perception of malaria,their treatment practices and the effects on the outcome of ***:Four hundred and sixty children were enrolled and their mothers/care givers *** children were screened for malaria parasitaemia and there after,blood specimens were obtained for biochemical and haematological evaluation from those children who met the criteria and tested positive to *** *** cell volume,electrolytes,urea, creatinine,plasma glucose,and serum bilirubin were ***:A total of 460 children were studied, 233(50.7%) males and 227(49.3%) *** malaria cases were 112(24.3%) and severe malaria 348(75.7%).Those who presented early 106(23.0%) and those who presented late 354(77.0%).Perception and definition of malaria as well as the treatment seeking behaviors vary significantly with the level of education of the mothers and care *** without formal education 68(51.9%) wrongly perceived that the etiology of malaria can only be diagnosed by native doctors compared to those with primary six education 61 (26.5%) and junior secondary education 10(10.1%).Only 43(9.3%) gave the correct dose of chloroquine syrup to their sick children,while 32(7.0%) gave at sub optimal ***:Wrong perception of malaria especially the complicated malaria and wrong treatment practices are major contributory factors to the high mortality and morbidity of malaria in *** is therefore a need for health education to correct the wrong ideas about the cause and treatment practices of malaria as part of malaria control programme.

关键词： Childhood malaria Mothers/Caregivers Perception and treatment practices Nigeria

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

Enhanced mechanical property by introducing bimodal grains structures in Cu-Ta alloys fabricated by mechanical alloying

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Journal of Materials Science & Technology 2024年第5期172卷 104-112页

作者： Ningyu li Yongqin chang Mingyang li Yuxiang Chen Xinrui luo Shichao Pei Fan Yang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Xi’an Rare Metal Materials Institute Co.ltd Xi’an 710016China

Dispersion-strengthened copper alloys can achieve ultra-high strength,but usually at the expense of *** this study,a strategy for overcoming strength-ductility tradeoffof Cu alloys is realized through the introduction of bimodal grains ***-Ta alloys with only 0.5 at.%Ta content were successfully prepared by mechanical alloying combined with spark plasm *** samples prepared by one-step and two-step ball milling methods are named as Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ),*** microstructural characterizations revealed that ultra-fine equiaxed grains with uniformly dispersed Ta precipitates were obtained in the Cu-Ta *** strength of 377 MPa for yield strength together with elongation of∼8%was obtained in Cu-Ta(Ⅰ).Bimodal grains structures composed of fine-grain zones and coarse-grain zones were successfully introduced into Cu-Ta(Ⅱ)by a two-step ball milling approach,and both yield strength(463 MPa)and elongation(∼15%)were significantly synergistic *** hardness values of both Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ)were almost kept nearly constant with the increase of annealing time,and the softening temperatures of Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ)are 1018 and 1013℃,reaching 93.9%and 93.5%T m of pure Cu(1083℃),*** reveals that the Cu-0.5 at.%Ta alloys exhibit excellent thermal stability and exceptional softening *** nanoclusters with semi-coherent structures play an essential role in enhancing the strength and microstructural stability of *** structures are beneficial to the activation of back stress strengthening and the initiation and propagation of microcracks,thus obtaining the extraordinary combination of strength and *** study provides a new way to fabricate dispersion-strengthened Cu alloys with high strength,high elongation,excellent thermal stability and softening resistance,which have potential application value in the field of the future fusion reactor.

关键词： Cu-Ta alloy Mechanical alloying Ta precipitates Bimodal structures Mechanical property

Benefit of aerosol reduction to winter wheat during China's clean air action:A case study of Henan Province

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Journal of Environmental Sciences 2024年第7期141卷 90-101页

作者： Yang Bai Pengfei Zhao Xueyang Chen lijun Wang Wenjuan chang Jianzhong Guo Jiayao Wang College of Geography and Environmental Science Henan UniversityKaifeng 475004China Henan Industrial Technology Academy of Spatio-Temporal Big Data Henan UniversityZhengzhou 475000China Henan Technology Innovation Center of Spatio-Temporal Big Data Henan UniversityZhengzhou 450046China Key laboratory of Geospatial Technology for the Middle and lower Yellow River Regions(Henan university) Ministry of EducationKaifeng 475000China

A strongly declining aerosol radiative effect has been observed in China since 2013 after implementing the clean air action,yet its impact on wheat(Triticum aestivum l.)production remains *** use satellite measures and a biophysical crop model to assess the impact of aerosol-induced radiative perturbations on winter wheat production in the agricul.ural belt of Henan province from 2013 to *** calibrating parameters with the extended Fourier Amplitude Sensitivity Test(EFAST)and the generalized likelihood uncertainty estimation(GluE)method,the DSSAT CERES-Wheat model was able to simulate crop biomass and yield more *** found that the aerosol negatively impacted wheat biomass by 21.87%and yield by 22.48%from 2006 to 2018,and the biomass effects from planting to anthesis were more significant compared to anthesis to *** to the strict clean air action,under all-sky conditions,the surface solar shortwave radiation(SSR)in 2018 increased by about 7.08%over 2006-2013 during the wheat growing *** a result of the improvement of crop photosynthesis,winter wheat biomass and yield increased by an average of 5.46%and 2.9%,*** findings show that crop carbon uptake and yield will benefit from the clean air action in China,helping to ensure national food and health security.

关键词： Haze pol.ution Clean air action Aerosol-induced radiative perturbation Wheat production DSSAT model

Design and construction of charged-particle telescope array for study of exotic nuclear clustering structure

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Nuclear Science and Techniques 2024年第8期35卷 114-123页

作者： Zheng‑li liao Xi‑Guang Cao Yu‑Xuan Yang chang‑Bo Fu Xian‑Gai Deng Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China university of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Zhengzhou university Zhengzhou 450001China Key laboratory of Nuclear Physics and Ion‑beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan university Shanghai 200438China

The exploration of exotic shapes and properties of atomic nuclei,e.g.,αcluster and toroidal shape,is a fascinating field in nuclear *** study the decay of these nuclei,a novel detector aimed at detecting multipleα-particle events was designed and *** detector comprises two layers of double-sided silicon strip detectors(DSSD)and a cesium iodide scintillator array coupled with silicon photomultipliers array as light sensors,which has the advantages of their small size,fast response,and large dynamic *** coupled with cesium iodide crystal arrays are used to distinguish multipleα*** detector array has a compact and integrated design that can be adapted to different experimental *** detector array was simulated using Geant4,and the excitation energy spectra of someα-clustering nuclei were reconstructed to demonstrate the *** simulation results show that the detector array has excellent angular and energy resolutions,enabling effective reconstruction of the nuclear excited state by multipleαparticle *** detector offers a new and powerful tool for nuclear physics experiments and has the potential to discover interesting physical phenomena related to exotic nuclear structures and their decay mechanisms.

关键词： Cluster decay Toroidal structure Telescope array SiPM Energy resolution

SMXl5 attenuates strigolactone signaling in Arabidopsis thaliana by inhibiting SMXl7 degradation

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Molecular Plant 2024年第4期17卷 631-647页

作者： Qingtian li Haiyang Yu Wenwen chang Sunhyun chang Michael Guzman lionel Faure Eva-Sophie Wallner Heqin Yan Thomas Greb lei Wang Ruifeng Yao David C.Nelson Department of Botany and Plant Sciences University of CaliforniaRiversideRiversideCA 2521USA Yazhouwan National laboratory Sanya 572025China Hainan Seed Industry laboratory Sanya 57205China State Key laboratory of Chemo/Biosensing and Chemometrics Hunan Provincial Key Laboratory of Plant Functional Genomics and Developmental RegulationCollege of BiologyHunan UniversityChangsha 410082China Key laboratory of Seed Innovation Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuangHebei 050021China university of Chinese Academy of Sciences Beijing 10004China School of the Sciences Biology DivisionTexas Woman’s UniversityDentonTX 76204USA Centre for Organismal Studies(COS) Heidelberg University6120 HeidelbergGermany

Hormone-activated proteolysis is a recurring theme of plant hormone signaling *** strigolactone signaling,the enzyme receptor DWARF14(D14)and an F-box protein,MORE AXIllARY GROWTH2(MAX2),mark SuPPRESSOR OF MAX21-lIKE(SMXl)family proteins SMXl6,SMXl7,and SMXl8 for rapid *** of these transcriptional corepressors initiates downstream growth *** homologous proteins SMXl3,SMXl4,and SMXl5,however,are resistant to MAX2-mediated *** discovered that the smxl4 smxl5 mutant has enhanced responses to ***5 attenuates strigolactone signaling by interfering with AtD14-SMXl7 ***5 interacts with AtD14 and SMXl7,providing two possible ways to inhibit SMXl7 ***5 function is partially dependent on an ethylene-responsive-element binding-factor-associated amphiphilic repression(EAR)motif,which typically mediates interactions with the TOPlESS family of transcriptional ***,we found that loss of the EAR motif reduces SMXl5-SMXl7 interactions and the attenuation of strigolactone signaling by *** hypothesize that integration of SMXl5 into heteromeric SMXl complexes reduces the susceptibility of SMXl6/7/8 proteins to strigolactone-activated degradation and that the EAR motif promotes the formation or stability of these *** mechanism may provide a way to spatially or temporally fine-tune strigolactone signaling through the regulation of SMXl5 expression or translation.

关键词： Arabidopsis typically inhibiting

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

Temporal assembly patterns of microbial communities in three parallel bioreactors treating low-concentration coking wastewater with differing carbon source concentrations

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Journal of Environmental Sciences 2024年第3期137卷 455-468页

作者： Weijia li Yu Xia Na li Jie chang Jing l.u Pei Wang Xuwen He School of Chemical and Environmental Engineering China University of Mining and Technology-BeijingBeijing 100083China

Carbon source is an important factor of biological treatment systems, the effects of which on their temporal community assembly patterns are not sufficiently understood *** this study, the temporal dynamics and driving mechanisms of the communities in three parallel bioreactors for low-concentration coking wastewater(CWW) treatment with differing carbon source concentrations(S0 with no glucose addition, S1 with 200 mg/l glucose addition and S2 with 400 mg/l glucose addition) were comprehensively studied. Highthroughput sequencing and bioinformatics analyses including network analysis and Infer Community Assembly Mechanisms by Phylogenetic bin-based null model(iCAMP) were used. The communities of three systems showed turnover rates of 0.0029~0.0034 every 15days. Network analysis results showed that the S0 network showed higher positive correlation proportion(71.43%) and clustering coefficient(0.33), suggesting that carbon source shortage in S0 promoted interactions and cooperation of microbes. The neutral community model analysis showed that the immigration rate increased from 0.5247 in S0 to 0.6478in S2. The iCAMP analysis results showed that drift(45.89%) and homogeneous selection(31.68%) dominated in driving the assembly of all the investigated microbial *** contribution of homogeneous selection increased with the increase of carbon source concentrations, from 27.92% in S0 to 36.08% in S2. The OTus participating in aerobic respiration and tricarboxylic acid(TCA) cycle were abundant among the bins mainly affected by deterministic processes, while those related to the metabolism of refractory organic pol.utants in CWW such as alkanes, benzenes and phenols were abundant in the bins dominated by stochastic processes.

关键词： Coking wastewater treatment Temporal dynamics Network analysis Deterministic processes Stochastic processes

Organic solar cells with D18 or derivatives offer efficiency over 19%

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Journal of Semiconductors 2024年第5期45卷 1-4页

作者： Erming Feng Chujun Zhang Jianhui chang Hengyue li liming Ding Junliang Yang Hunan Key laboratory for Super-microstructure and ultrafast Process School of PhysicsCentral South UniversityChangsha 410083China Center for Excellence in Nanoscience Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China

In recent years,organic solar cells(OSCs)have garnered significant attention due to their distinctive attributes,such as flexibility,lightweight,and solution processing,which position them as alternatives for next-generation solar technologies[1−5].Thanks to breakthroughs in materials development,the power conversion efficiency(PCE)for single-junction OSCs has already surpassed 19%[6−13].The development of photoactive materials is pivotal in enhancing the PCEs,and several reviews have provided insights into materials design[14−18].Herein,we highlight single-junction OSCs based on D18 and its derivatives[19,20].

关键词： breakthrough insight derivatives