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Effect of droplet characteristics on liquid-phase distribution in spray zone of internal mixing air-mist nozzle

China Foundry 2024年第2期21卷 185-196页

作者： Wei-li Wu Chang-gui Cheng Yang Li Shi-fa Wei De-li Chen The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081China Technology Center Fushun Special Steel Co.Ltd.Fushun 113001LiaoningChina

In continuous casting production,droplet characteristics are important parameters for evaluating the nozzle atomization quality,and have a significant impact on the secondary cooling effect and the slab *** order to study the behavior of atomized droplets after reaching the slab surface and to optimize the spray cooling effect,the influence of droplet diameter and droplet velocity on the migration behavior of droplets in the secondary cooling zone was analyzed by FLUENT *** show that the droplets in the spray zone and on the slab surface are mainly concentrated in the center,thus,the liquid volume fraction in the center is higher than that of either *** the droplet diameter increases,the region of high liquid volume fraction on the slab surface becomes wider,and the liquid phase distribution in the slab width direction becomes *** increasing the droplet velocity at the nozzle exit has little effect on droplet diffusion in the spray zone,the distribution becomes more uneven due to more liquid reaches the slab surface per unit time.A prediction formula of the maximum water flow rate on the slab surface for specific droplet characteristics was proposed based on dimensionless analysis and validated by simulated data.A nozzle spacing of 210 mm was recommended under the working conditions in this study,which ensures effective coverage of the spray water over the slab surface and enhances the distribution uniformity of water flow rate in the transverse direction.

关键词： continuous casting secondary cooling zone internal mixing air-mist nozzle droplet characteristics liquid phase distribution water flow rate

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An improved deep dilated convolutional neural network for seismic facies interpretation

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Petroleum Science 2024年第3期21卷 1569-1583页

作者： Na-Xia Yang Guo-fa Li Ting-Hui Li Dong-Feng Zhao Wei-Wei Gu State Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical ExplorationChina University of Petroleum(Beijing)Beijing 102249China Dagang Branch Research InstituteBGPTianjin300280China

With the successful application and breakthrough of deep learning technology in image segmentation,there has been continuous development in the field of seismic facies interpretation using convolutional neural *** intelligent and automated methods significantly reduce manual labor,particularly in the laborious task of manually labeling seismic ***,the extensive demand for training data imposes limitations on their wider *** overcome this challenge,we adopt the UNet architecture as the foundational network structure for seismic facies classification,which has demonstrated effective segmentation results even with small-sample training ***,we integrate spatial pyramid pooling and dilated convolution modules into the network architecture to enhance the perception of spatial information across a broader *** seismic facies classification test on the public data from the F3 block verifies the superior performance of our proposed improved network structure in delineating seismic facies *** analysis against the traditional UNet model reveals that our method achieves more accurate predictive classification results,as evidenced by various evaluation metrics for image ***,the classification accuracy reaches an impressive 96%.Furthermore,the results of seismic facies classification in the seismic slice dimension provide further confirmation of the superior performance of our proposed method,which accurately defines the range of different seismic *** approach holds significant potential for analyzing geological patterns and extracting valuable depositional information.

关键词： Seismic facies interpretation Dilated convolution Spatial pyramid pooling Internal feature maps Compound loss function

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Forecast of cosmological constraints with superluminous supernovae from the Chinese Space Station Telescope

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 128-138页

作者： Xuan-Dong Jia Jian-Ping Hu fa-Yin Wang Zi-Gao Dai School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210093China Department of Astronomy University of Science and Technology of ChinaHefei 230026China

Superluminous supernovae(SLSNe)are a class of intense celestial events that can be standardized for measuring cosmological parameters,bridging the gap between type ia supernovae and the cosmic microwave *** this work,we discuss the cosmological applications of SLSNe from the Chinese Space Station Telescope(CSST).Our estimation suggests that SLSNe rate is biased tracing the cosmic star formation rate,exhibiting a factor of(1+z)^(1.2).We futher predict that CSST is poised to observe~360 SLSNe in the 10 square degrees ultra-deep field survey within a span of 2.5 years.A stringent constraint on cosmological parameters can be derived from their peak-color *** is anticipated to uncover a substantial number of SLSNe,contributing to a deeper understanding of their central engines and shedding light on the nature of dark energy at high redshifts.

关键词： supernovae cosmology cosmological constant

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Prevalence of prolonged grief disorder and its symptoms among bereaved individuals in China:a systematic review and meta-analysis

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General Psychiatry 2024年第2期37卷 177-188页

作者： Meng-Di Yuan Jun-fa Liu Bao-Liang Zhong Research Center for Psychological and Health Sciences China University of Geosciences(Wuhan)WuhanHubeiChina Department of Psychiatry Wuhan Mental Health CentreWuhanHubeiChina

Background The prevalence of prolonged grief disorder(PGD)and its symptoms among the bereaved population in China vary *** This meta-analysis aims to estimate the prevalence of PGD and its symptoms among bereaved individuals in *** We conducted a literature search in major Chinese and English databases from their inception to 4 October 2023,for cross-sectional studies on the prevalence of PGD or its symptoms in bereaved Chinese *** risk of bias of the included studies and certainty of the evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data(‘JBI checklist’)and the Grading of Recommendations,Assessment,Development and Evaluations(GRADE),***‘metaprop’package in R V.4.1.2 was used to synthesise the *** A total of 28 studies involving 10994 bereaved individuals were included in the analysis,with JBI checklist scores between 3 and *** combined prevalence(95%confidence interval)of PGD and its symptoms was 8.9%(4.2%to 17.6%)and 32.4%(18.2%to 50.8%),*** and its symptoms were most prevalent among those who had lost their only child(22.7%)and those bereaved by earthquakes(80.4%),*** GRADE system assigned a very low certainty level to the evidence for the pooled prevalence of PGD and its *** The pooled prevalence of PGD and its symptoms indicate a potential high need for grief counselling services among bereaved individuals in *** need is particularly pronounced in those who have lost their only child and those bereaved due to *** methodologically rigorous studies are needed to provide more accurate prevalence *** registration number CRD42023432553.

关键词： symptoms prevalence analysis

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Impact of ozonation on disinfection byproducts formation from phenylalanine during chlorination

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Journal of Environmental Sciences 2024年第10期144卷 199-211页

作者： Sinong Huang Hongwei Liu Kunming Wei Liang Zhang Xiaoyan Ma Qingsong Li Xueyan Li Andrea M.dietrich College of Civil Engineering Zhejiang Key Laboratory of Civil Engineering Structures&Disaster Prevention and Mitigation TechnologyZhejiang University of TechnologyHangzhou 310023China Water Resources and Environmental Institute Xiamen University of TechnologyXiamen 361005China School of Environmental Science and Engineering Suzhou University of Science and TechnologySuzhou 215009China Civil and Environmental Engineering Virginia Polytechnic Institute and State UniversityBlackburgVA 24061USA

As a strong oxidizing agent,ozone is used in some water treatment facilities for disinfection,taste and odor control,and removal of organic ***(Phe)was used as the target amino acid to comprehensively investigate variability of disinfection byproducts(DBPs)formation during chlorine disinfection and residual chlorine conditions subsequent to *** results showed that subsequent to ozonation,the typical regulated and unregulated DBPs formation potential(DBPsFP),including trichloromethane(TCM),dichloroacetonitrile(DCAN),chloral hydrate(CH),dichloroacetic acid(DCAA),trichloroacetic acid(TCAA),and trichloroacetamide(TCAcAm)increased substantially,by 2.4,3.3,5.6,1.2,2.5,and 6.0 times,respectively,compared with only *** also significantly increased the DBPs yield under a 2 day simulated residual chlorine condition that mimicked the water distribution *** formations followed pseudo first order *** formation rates of DBPs in the first 6 hr were higher for TCM(0.214 hr^(−1)),DCAN(0.244 hr^(−1)),CH(0.105 hr^(−1)),TCAcAm(0.234 hr^(−1)),DCAA(0.375 hr^(−1))and TCAA(0.190 hr^(−1))than *** peak DBPsFP of TCM,DCAN,CH,TCAcAm,DCAA,and TCAA were obtained when that ozonation time was set at 5–15 *** times>30 min increased the mineralization of Phe and decreased the formation of DBPs upon *** bromine ion(Br^(−1))concentration increased production of bromine-DBPs and decreased chlorine-DBPs formation by 59.3%–92.2%.Higher ozone dosages and slight alkaline favored to reduce DBP formation and *** ozonation conditions should be optimized for all application purposes including DBPs reduction.

关键词： Ozone Amino acids Chlorination Disinfection by-products

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Continuous gradient fusion class activation mapping: segmentation of laser-induced damage on large-aperture optics in dark-field images

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High Power Laser Science and Engineering 2024年第1期12卷 30-41页

作者： Yueyue Han Yingyan Huang Hangcheng Dong Fengdong Chen fa Zeng Zhitao Peng Qihua Zhu Guodong Liu School of Instrumentation Science and Engineering Harbin Institute of TechnologyHarbinChina Research Center of Laser Fusion China Academy of Engineering PhysicsMianyangChina

Segmenting dark-field images of laser-induced damage on large-aperture optics in high-power laser facilities is challenged by complicated damage morphology, uneven illumination and stray light interference. Fully supervised semantic segmentation algorithms have achieved state-of-the-art performance but rely on a large number of pixel-level labels, which are time-consuming and labor-consuming to produce. LayerCAM, an advanced weakly supervised semantic segmentation algorithm, can generate pixel-accurate results using only image-level labels, but its scattered and partially underactivated class activation regions degrade segmentation performance. In this paper, we propose a weakly supervised semantic segmentation method, continuous gradient class activation mapping(CAM) and its nonlinear multiscale fusion(continuous gradient fusion CAM). The method redesigns backpropagating gradients and nonlinearly activates multiscale fused heatmaps to generate more fine-grained class activation maps with an appropriate activation degree for different damage site sizes. Experiments on our dataset show that the proposed method can achieve segmentation performance comparable to that of fully supervised algorithms.

关键词： class activation maps laser-induced damage semantic segmentation weakly supervised learning

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Magnetism and Superconductivity in the t–J Model of La_(3)Ni_(2)O_7 Under Multiband Gutzwiller Approximation

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Chinese Physics Letters 2024年第5期41卷 97-106页

作者：薛洁然王垡 International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

The recent discovery of possible high temperature superconductivity in single crystals of La_(3)Ni_(2)O_(7) under pressure renews the interest in research on *** density functional theory calculations reveal that both d_(z^(2)) and d_(x^(2)-y^(2)) orbitals are active,which suggests a minimal two-orbital model to capture the low-energy physics of this *** this work,we study a bilayer two-orbital t–J model within multiband Gutzwiller approximation,and discuss the magnetism as well as the superconductivity over a wide range of the hole *** to the inter-orbital super-exchange process between d_(z^(2)) and d_(x^(2)-y^(2)) orbitals,the induced ferromagnetic coupling within layers competes with the conventional antiferromagnetic coupling,and leads to complicated hole doping dependence for the magnetic properties in the *** increasing hole doping,the system transfers to A-type antiferromagnetic state from the starting G-type antiferromagnetic(G-AFM)*** also find the inter-layer superconducting pairing of d_(x^(2)-y^(2)) orbitals dominates due to the large hopping parameter ofd_(z^(2)) along the vertical inter-layer bonds and significant Hund’s coupling between d_(z^(2)) and d_(x^(2)-y^(2)) ***,the G-AFM state and superconductivity state can coexist in the low hole doping *** take account of the pressure,we also analyze the impacts of inter-layer hopping amplitude on the system properties.

关键词： properties doping orbital

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Highly crystallization-induced emissive luminophores with mechanoluminescent features for two-photon harvesting fluorescence imaging and latent fingerprint identification

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Nano Research 2024年第7期17卷 6475-6482页

作者： Jian Lu Juan Gao Rui-Xuan Qian Shuai-Hua Wang fa-Kun Zheng Guo-Cong Guo Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Fluorescence imaging can be employed in fields of medical treatment,astronomical exploration,and national defense *** fluorescence imaging often takes the single-photon techniques,which is vulnerable to background interference and ***,two-photon fluorescence imaging can achieve much higher-resolution fluorescence imaging for reducing scattering and deeper ***,by assembling the tetraphenylethylene backbones with nontoxic and non-noble K^(+)ions,compound 1([(Hdma)K(H_(2)ettc)]_(n),H_(4)ettc=4',4''',4''''',4'''''''-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1'-biphenyl]-4-carboxylic acid)))with the crystallization-induced emissions exhibited charming fluorescence imaging under two-photon excitation microscopy(TPEM).Besides,luminescent powders based on compound 1 can achieve high-resolution fingerprint recognition,providing secure access control and identification for a novel authentication *** with the commercial fluorescent dyes coumarin-6,the as-synthesized compound 1 showed great solvent stability,indicating its durability against harsh ***,compound 1 shows mechanoluminescent properties for the perturbation of weak supramolecular interactions within ordered arrangements of the H_(2)ettc^(2−)*** novel compound has provided an important insight to the development of twophoton fluorescence imaging and advanced external-stimuli responsive materials.

关键词： crystallization-induced emission fluorescence imaging two-photon absorption fingerprint recognition mechanoluminescence

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Overexpression of wild-type HRAS drives non-alcoholic steatohepatitis to hepatocellular carcinoma in mice

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Zoological Research 2024年第3期45卷 551-566页

作者： Chen Ling Su-Su Liu Yu-Ya Wang Gui-Tao Huo Yan-Wei Yang Nan Xu Hong Wang Yong Wu Yu-fa Miao Rui Fu Yu-Wei Zhao Chang-fa fan College of Life Sciences Northwest UniversityProvincial Key Laboratory of Biotechnology of Shaanxi ProvinceXi’anShaanxi 710069China Division of Animal Model Research Institute for Laboratory Animal ResourcesNational Institutes for Food and Drug Control(NIFDC)Beijing 102629China National Center for Safety Evaluation of Drugs National Institutes for Food and Drug Control(NIFDC)Beijing 100176China Division of HIV/AIDS and Sexually Transmitted Virus Vaccines Institute for Biological Products ControlNational Institutes for Food and Drug Control(NIFDC)Beijing 102629China Division of Laboratory Animal Monitoring Institute for Laboratory Animal ResourcesNational Institutes for Food and Drug Control(NIFDC)Beijing 102629China

Hepatocellular carcinoma(HCC),a prevalent solid carcinoma of significant concern,is an aggressive and often fatal disease with increasing global incidence rates and poor therapeutic *** etiology and pathological progression of non-alcoholic steatohepatitis(NASH)-related HCC is multifactorial and ***,no single animal model can accurately mimic the full NASH-related HCC pathological progression,posing considerable challenges to transition and mechanistic ***,a novel conditional inducible wild-type human HRAS overexpressed mouse model(HRAS-HCC)was established,demonstrating 100%morbidity and mortality within approximately one month under normal dietary and lifestyle *** symptoms of HCC such as ascites,thrombus,internal hemorrhage,jaundice,and lung metastasis were successfully replicated in ***-depth pathological features of NASH-related HCC were demonstrated by pathological staining,biochemical analyses,and typical marker gene *** murine anti-PD-1 and sorafenib treatment effectively prolonged mouse survival,further confirming the accuracy and reliability of the *** on protein-protein interaction(PPI)network and RNA sequencing analyses,we speculated that overexpression of HRAS may initiate the THBS1-COL4A3 axis to induce NASH with severe fibrosis,with subsequent progression to ***,our study successfully duplicated natural sequential progression in a single murine model over a very short period,providing an accurate and reliable preclinical tool for therapeutic evaluations targeting the NASH to HCC continuum.

关键词： HRAS THBS1 HCC driver factor NASH Fibrosis Cirrhosis HCC Treatment evaluation

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FP-Zernike:An Open-source Structural Database Construction Toolkit for fast Structure Retrieval

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 111-119页

作者： Junhai Qi Chenjie Feng Yulin Shi Jianyi Yang fa Zhang Guojun Li Renmin Han Research Center for Mathematics and Interdisciplinary Sciences Shandong UniversityQingdao 266237China BioMap Research Menlo ParkCA 94025USA College of Medical Information and Engineering Ningxia Medical UniversityYinchuan 750004China Institute of Engineering Medicine Beijing Institute of TechnologyBeijing 100081China

The release of AlphaFold2 has sparked a rapid expansion in protein model *** protein structure retrieval is crucial for the analysis of structure models,while measuring the similarity between structures is the key challenge in structural *** existing structure alignment algorithms can address this challenge,they are often ***,the state-of-the-art approach involves converting protein structures into three-dimensional(3D)Zernike descriptors and assessing similarity using Euclidean ***,the methods for computing 3D Zernike descriptors mainly rely on structural surfaces and are predominantly web-based,thus limiting their application in studying custom *** overcome this limitation,we developed FP-Zernike,a user-friendly toolkit for computing different types of Zernike descriptors based on feature *** simply need to enter a single line of command to calculate the Zernike descriptors of all structures in customized ***-Zernike outperforms the leading method in terms of retrieval accuracy and binary classification accuracy across diverse benchmark *** addition,we showed the application of FP-Zernike in the construction of the descriptor database and the protocol used for the Protein Data Bank(PDB)dataset to facilitate the local deployment of this tool for interested *** demonstration contained 590,685 structures,and at this scale,our system required only 4-9 s to complete a *** experiments confirmed that it achieved the state-of-the-art accuracy ***-Zernike is an open-source toolkit,with the source code and related data accessible at https://***/biocode/tools/BT007365/releases/0.1,as well as through a webserver at http://***/.

关键词： Zernike descriptor Structure alignment PDB dataset Open-source Retrieval system

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