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Journal of Environmental Sciences 2024年第6期140卷 37-45页

作者： Zaiyong Jiang Hao Li Zhimin Yuan Zheng Wang maohong Fan Wenkang miao Hong he State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Chemistry&Chemical Engineering and Environmental Engineering Weifang UniversityWeifangShandong 261061China Departments of Chemical and Petroleum Engineering University of WyomingLaramieWY 82071USA materials Genome Institute Shanghai UniversityShanghai 200444China

Constructing own oxygen vacancies in the photocatalysts is a very promising method to improve their photocatalytic CO_(2)reduction ***,some catalysts have excellent stabilities,making it difficult for them to construct their own oxygen *** simplify the above difficulty of stable photocatalysts,constructing extrinsic oxygen vacancies on their surface as a novel idea is ***,a stable TiO_(2)nanosheet is chosen as a research object,we uniformly deposited BiOCl quantum dots on their surface via a simple adsorption-deposition *** is found that BiOCl quantum dots are able to simultaneously self-transform into defective BiOCl with many oxygen vacancies when the photocatalyst is performed photocatalytic CO_(2)*** extrinsic oxygen vacancies can act as“CO_(2)and photo-generated electrons reservoirs”to improve CO_(2)capture and accelerate the separation of photogenerated electrons and *** the above reasons,the modified TiO_(2)showed obvious enhancement of photocatalytic CO_(2)reduction compared to pristine TiO_(2)and *** work may open a new avenue to broaden the use of oxygen vacancies in the process of photocatalytic CO_(2)reduction.

关键词： Oxygen vacancy BiOCl Photocatalyst CO_(2)reduction TiO_(2)

Tuning heterogeneous microstructures to enhance mechanical properties of nano-TiN particle reinforced Haynes 230 composites by laser powder bed fusion

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Rare metals 2024年第9期43卷 4548-4565页

作者： Wen-Jie Liu Hui Li Qian-Xing Yin he-Jun Du School of Power and mechanical Engineering Wuhan University The Institute of Technological Sciences Wuhan University School of mechanical&Aerospace Engineering Nanyang Technological University

Laser powder bed fusion(LPBF) is considered to be one of the most promising additive manufacturing technologies for producing components with geometries and high geometrical precision that are unattainable by traditional technologies. The superalloy exhibits exceptional mechanical and high-temperature performances,rendering it a prime candidate for advanced aero-engine applications. Despite the high demand for LPBF-manufactured superalloys, the superalloy is one of the materials manufactured difficultly by LPBF due to their large laser absorptivity fluctuation, poor molten pool stability and sharp temperature gradient. hence, superalloys are characterized by severe pores, undesirable coarse columnar grains and poor mechanical properties. In this work, the effect of nano-Ti N particles on defects, molten pool characteristics and microstructure and performance of the composites were investigated. The 4.5 wt% Ti N/Haynes230 samples exhibited exceptional nanohardness and elastic modulus with maximum values reaching 5.53 GPa and 240.03 GPa, respectively. These superior mechanical properties were attributed to the combined effects of spatter and gas pore inhibition, grain refinement and duplex nanophases strengthening. moreover, the stability of molten pool was enhanced, and spatter was effectively suppressed by adding nano-Ti N particles, while grain refinement and columnar to equiaxed transitions were promoted. Furthermore, the matrix exhibited a high dislocation density due to a significant hindrance of dislocation movement caused by massive nano-phases(e.g., Ti N and m23C6), resulting in the formation of extensive dislocation tangles and *** work offers novel insights into the role of nanoparticles reinforced superalloy composites by LPBF.

关键词： Composites Laser powder bed fusion mechanical properties microstructure molten pool characteristics

Understanding the mechanism for the In-Plane Yielding Anisotropy of a Hot-Rolled Zirconium Plate

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Acta metallurgica Sinica(English Letters) 2024年第6期37卷 1066-1076页

作者： Guodong Song Conghui Zhang Yunchang Xin Nobuhiro Tsuji Xinde Huang Bo Guan Xiaomei he School of metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055China Key Laboratory for Light-Weight materials Nanjing Tech UniversityNanjing210009China Department of materials Science and Engineering Kyoto UniversityYoshida-honmachiSakyo-kuKyoto606-8501Japan Institute of Applied Physics Jiangxi Academy of ScienceNanchang330029China

Previously,the in-plane mechanical anisotropy of Zr hot-rolled plates is ascribed mainly to the different activities of the deformation modes activated when loading along different *** this work,a quantitative study on the deformation behavior of a pure Zr hot-rolled plate under tension along the rolling direction(RD)and transverse direction(TD)reveals that both the activities of deformation modes and the anisotropy of grain boundary strengthening account for a tensile yield strength anisotropy along the TD and *** plasticity simulations using viso-plastic self-consistent model show that prismatic slip is the predominant deformation mode for tension along the RD(RD-tension),while prismatic slip and basal slip are co-dominant deformation modes under tension along the TD(TD-tension).A low fraction of■under TD-tension,while hardly activated under *** activation of basal slip with a much higher critical resolve shear stress under TD-tension contributes to a higher yield strength along the TD than along the *** grain boundary strengthening effect under tension along the TD and RD were compared by calculating the activation stress difference(△Stress)and the geometric compatibility factor(m′)between neighboring *** results indicate a higher grain boundary strengthening for TD-tension than that for RD-tension,which will lead to a higher yield strength along the *** is,the anisotropy of grain boundary strengthening between TD-tension and RD-tension also plays an important role in the in-plane anisotropy along the RD and ***,the reasons for why there is a grain-boundary-strengthening anisotropy along the TD and RD were discussed.

关键词： Zirconium Strengthening Grain boundary Orientation

Step-over of strike-slip faults and overpressure fluid favor occurrence of foreshocks:Insights from the 1975 Haicheng fore-main-aftershock sequence,China

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Earthquake Research Advances 2024年第1期4卷 36-46页

作者： Xinglin Lei Zhiwei Wang Shengli ma Changrong he Geological Survey of Japan AISTTsukuba305-8567Japan State Key Laboratory of Earthquake Dynamics Institute of GeologyCEABeijing100029 China

This study analyzed and summarized in detail the spatial and temporal distributions of earthquakes,tidal responses,focal mechanisms,and stress field characteristics for the m 7.3 Haicheng earthquake sequence in February *** foreshocks are related to the main fault and the conjugate faults surrounding the extension step-over in the *** initiation timing of the foreshock clusters and the original time of the mainshock were clearly modulated by the Earth's tidal force and coincided with the peak of dilational volumetric tidal *** a plausible and testable hypothesis,we proposed a fluid-driven foreshock model,by which all observed seismicity features can be more reasonably interpreted with respect to the results of existing *** with some other known examples,the widely existing step-over along strike-slip faults and associated conjugate faults,especially for extensional ones in the presence of deep fluids,favor the occurrence of short-term *** clustered seismicity with characteristics similar to those of the studied case is not a sufficient and necessary condition for large earthquakes to occur under similar tectonic conditions,it undoubtedly has a warning significance for the criticality of the main *** testing would require quantification of true/false positives/negatives.

关键词： Haicheng earthquake Seismogenic fault ETAS Foreshock Deep fluid

Fabricating functionally graded Fe-Cr-Co permanent magnetic alloys via laser powder bed fusion

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Journal of Iron and Steel Research(International) 2024年第3期31卷 729-737页

作者： Ya-zhou he Ya-qing Hou Peng Shen Hao Zhang Dong Zhou Hang Su Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China material Digital R&D Center China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China

Laser powder bed fusion(LPBF)in-situ alloying technology offers the possibility to construct gradient materials with varied structures and *** graded Fe-Cr-Co permanent magnetic alloys were fabricated by LPBF and in-situ alloying mixed powders of Fe,Cr,and Co *** effects of different Fe,Cr and Co contents on the microstructure,magnetic properties and hardness of Fe-Cr-Co alloys prepared by LPBF were *** as-built Fe-Cr-Co alloys present a single body-centered-cubic phase and have a homogeneous distribution of *** mechanical properties and magnetic properties of the compositionally graded sample show a gradient *** the increase in Cr content,the Vickers hardness of the sample increases,and the saturation magnetization of the sample *** optimal magnetic properties in an isotropic state are given as coercivity HcB=21.65 kA/m,remanence Br=0.70 T and energy product(BH)_(max)=5.35 kJ/m^(3),which are comparable to or higher than the reported magnetic properties in an isotropic state prepared by traditional powder *** in-situ alloying technology has the potential to further explore Fe-Cr-Co magnetic materials,such as those consisting of multiple or more constituent elements,and to maximize the compositional flexibility of magnetic materials.

关键词： Fe-Cr-Co alloy Laser powder bed fusion In-situ alloying Functional material magnetic property

Technetium-99m-methylene diphosphonate single photon emission computed tomography/computed tomography combined with prostate-specific antigen/free prostate-specific antigen ratio for bone metastasis of prostate cancer

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World Journal of Clinical Cases 2024年第20期12卷 4082-4090页

作者： Jian he Yi-Pu Zhong Shuang Zhang Department of Nuclear medicine Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina Department of Nuclear medicine The People’s Hospital of JianyangJianyang 641400Sichuan ProvinceChina

BACKGROUND Prostate cancer(PC)is one of the most common malignant tumors in men,and bone metastasis is one of its common complications,which seriously affects the quality of life and prognosis of *** To investigate the diagnostic value of technetium-99m-methylene diphosphonate(99mTc-mDP)single photon emission computed tomography(SPECT)/CT imaging combined with the serum prostate-specific antigen(PSA)/free PSA ratio for PC bone metastasis(PCBm).mETHODS One hundred patients with PC who visited the Hospital of Chengdu University of Traditional Chinese medicine from January 2020 to January 2022 were recruited as the experimental(Exp)group,while 30 patients with benign prostatic lesions(BPLs)were recruited as the control(Ctrl)*** patients underwent 99mTc-mDP SPECT/CT imaging and serum PSA/fPSA *** SPECT/CT imaging results and serum PSA/fPSA ratios of patients were analyzed to evaluate their diagnostic values for *** The difference in general information of the patients was not obvious,showing *** two methods showed no visible differences in negative predictive value and sensitivity for patients with PCBm,but had great differences in positive predictive value and specificity(Phe PSA/fPSA ratio of patients with PC in the Exp group was lower than those with BPLs,and patients with PCBm had a much lower PSA/fPSA ratio than those without PC(Phe results confirmed that the combined use of 99mTc-mDP SPECT/CT imaging and serum PSA/fPSA ratio achieved a detection rate of 95%for *** The combination of 99mTc-mDP SPECT/CT and PSA/fPSA ratio is accurate and reliable for the diagnosis of PCBm,which provides an important reference for clinical practice.

关键词： matrix metalloproteinase 9 Single photon emission computed tomography Prostate-specific antigen to free prostate-specific antigen ratio Prostate cancer Bone metastasis

The Orthogonal Bases of Exponential Functions Based on moran-Sierpinski measures

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Acta mathematica Sinica,English Series 2024年第7期40卷 1804-1824页

作者： Qi Rong DENG Xing Gang he ming Tian LI Yuan Ling YE School of mathematics and Statistics Center for Applied Mathematics of Fujian Province&Key Laboratory of Analytical Mathematics and Applications(Ministry of Education)Fujian Normal UniversityFuzhou350117P.R.China School of mathematics and Statistics Key Lab NAA-MOE and Hubei Key Lab-Math.Sci.Central China Normal UniversityWuhan430079P.R.China School of mathematical Sciences&South China Research Center for Applied mathematics and Interdisciplinary Studies South China Normal UniversityGuangzhou510631P.R.China

Let An∈m2(ℤ)be integral matrices such that the infinite convolution of Dirac measures with equal weightsμ{A_(n),n≥1}δA_(1)^(-1)D*δA_(1)^(-1)A_(2)^(-2)D*…is a probability measure with compact support,where D={(0,0)^(t),(1,0)^(t),(0,1)^(t)}is the Sierpinski *** prove that there exists a setΛ⊂ℝ2 such that the family{e2πi〈λ,x〉:λ∈Λ} is an orthonormal basis of L^(2)(μ{A_(n),n≥1})if and only if 1/3(1,-1)A_(n)∈Z^(2)for n≥2 under some metric conditions on A_(n).

关键词： moran-Sierpinski measures orthonormal basis of exponential functions self-affine measures spectral measures

Vagus nerve stimulation in cerebral stroke:biological mechanisms,therapeutic modalities,clinical applications,and future directions

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Neural Regeneration Research 2024年第8期19卷 1707-1717页

作者： Li Du Xuan he Xiaoxing Xiong Xu Zhang Zhihong Jian Zhenxing Yang Department of Anesthesiology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina Department of Neurosurgery Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Stroke is a major disorder of the central nervous system that poses a serious threat to human life and quality of *** stro ke victims are left with long-term neurological dysfunction,which adversely affects the well-being of the individual and the broader socioeconomic ***,poststroke brain dysfunction is a major and difficult area of *** nerve stimulation is a Food and Drug Administration-approved exploratory treatment option for autis m,refractory depression,epilepsy,and Alzheimer’s *** is expected to be a novel therapeutic technique for the treatment of stroke owing to its association with multiple mechanisms such as alte ring neurotransmitters and the plasticity of central neuro *** animal models of acute ischemic stroke,vagus nerve stimulation has been shown to reduce infarct size,reduce post-stroke neurological damage,and improve learning and memory capacity in rats with stroke by reducing the inflammatory response,regulating bloodbrain barrier permeability,and promoting angiogenesis and *** present,vagus nerve stimulation includes both invasive and non-invasive vagus nerve *** studies have found that invasive vagus nerve stimulation combined with rehabilitation therapy is effective in im proving upper limb motor and cognitive abilities in stroke *** clinical studies have shown that non-invasive vagus nerve stimulation,including ear/ce rvical vagus nerve stimulation,can stimulate vagal projections to the central nervous system similarly to invasive vagus nerve stimulation and can have the same *** this paper,we first describe the multiple effects of vagus nerve stimulation in stroke,and then discuss in depth its neuroprotective mechanisms in ischemic *** go on to outline the res ults of the current major clinical applications of invasive and non-invasive vagus nerve ***,we provide a more comprehensive evaluation of the advantages and disadvantages of di

关键词： cerebral stroke neuroplasticity non-invasive vagus nerve stimulation rehabilitation vagus nerve stimulation

P-aminobenzoic acid promotes retinal regeneration through activation of Ascl1a in zebrafish

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Neural Regeneration Research 2024年第8期19卷 1849-1856页

作者： meihui he mingfang Xia Qian Yang Xingyi Chen Haibo Li Xiaobo Xia Eye Center of Xiangya Hospital Central South UniversityChangshaHunan ProvinceChina Hunan Key Laboratory of Ophthalmology ChangshaHunan ProvinceChina National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina

The retina of zebrafish can regenerate completely after injury.m ultiple studies have demonstrated that metabolic alte rations occur during retinal damage;however to date no study has identified a link between metabolites and retinal regeneration of ***,we performed an unbiased metabolome sequencing in the N-methyl-D-aspartic acid-damaged retinas of zebrafish to demonstrate the metabolomic mechanism of retinal *** the differentially-ex pressed metabolites,we found a significant decrease in p-aminobenzoic acid in the N-methyl-D-aspartic acid-damaged retinas of ***,we investigated the role of p-aminobenzoic acid in retinal regeneration in adult *** rtantly,p-aminobenzoic acid activated Achaetescute complex-like 1a expression,thereby promoting müller glia reprogramming and division,as well as müller glia-derived progenitor cell ***,we eliminated folic acid and inflammation as downstream effectors of PABA and demonstrated that PABA had little effect on müller glia *** together,these findings show that PABA contributes to retinal regeneration through activation of Achaetescute complex-like 1a expression in the N-methyl-Daspartic acid-damaged retinas of zebrafish.

关键词： Achaetescute complex-like 1a(Ascl1a) metabolomics müller glia p-aminobenzoic acid(PABA) retina regeneration zebrafish

Design of an on‑chip wavelength conversion device assisted by an erbium‑ytterbium co‑doped waveguide amplifier

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Frontiers of Optoelectronics 2024年第2期17卷 51-60页

作者： Chen Zhou Xiwen he mingyue Xiao Deyue ma Weibiao Chen Zhiping Zhou School of Physical Sciences University of Science and Technology of ChinaHefei 230026China Aerospace Laser Technology and System Department Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Hangzhou Aijie Optoelectronic Technology Co.Ltd. Hangzhou 311400China

In current documented studies,it has been observed that wavelength converters utilizing AlGaAsOI waveguides exhibit suboptimal on-chip wavelength conversion efficiency from the C-band to the 2μm band,generally falling below−20.0 *** address this issue,we present a novel wavelength conversion device assisted by a waveguide amplifier,incorporating both AlGaAs wavelength converter and erbium-ytterbium co-doped waveguide amplifier,thereby achieving a notable conversion efficiency exceeding 0 *** noteworthy enhancement in efficiency can be attributed to the specific dispersion design of the AlGaAs wavelength converter,which enables an upsurge in conversion efficiency to−15.54 dB under 100 mW of pump ***,the integration of an erbium-ytterbium co-doped waveguide amplifier facilitates a loss compensation of over 15 *** the use of external optical amplifiers,this device enables efficient and high-bandwidth wavelength conversion,showing promising applications in various fields,such as optical communication,sensing,imaging,and beyond.

关键词： Silicon-based optoelectronics Wavelength conversion Waveguide amplifier 2μm band