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Frontiers of Materials Science 2016年第1期10卷 38-44页

作者： chao-qing yang Ao-Ju LI Wei GUO Peng-Hua TIAN Xiao-Long YU Zhong-Xin LIU yang CAO Zhong-Liang SUN Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources Hainan University Haikou 570228 China

In a route boiling water served as reaction medium, a stoichiometric amount of rare-earth compound and fluoride are put into this system to form a-NaYF4：Yb, Er nuclei. Then prepared sample is heated at elevated temperature to improve the fluorescence intensity, and next a NaGdF4 shell grows on the surface of NaYF4 nuclei. NaYF4：Yb,ErlNaGdF4 core-shell structured upconversion nanoparticles （CSUCNPs） have been successfully synthesized by above route. The use of boiling water decreases the cubic-to-hexagonal phase transition temperature of NaYF4：Yb,Er to 350℃ and increases its upconversion （UC） luminescence intensity. A heterogeneous NaGdF4 epitaxially growing on the surface of Ln^3＋-doped NaYF4 not only improves UC luminescence, but also creates a paramagnetic shell, which can be used as contrast agents in magnetic resonance imaging （MRI）o The solution of CSUCNPs shows bright green UC fluorescence under the excitation at 980 nm in a power density only about 50 ***-2. A broad spectrum with a dominant resonance at g of about 2 is observed by the electron paramagnetic resonance （EPR） spectrum of CSUCNPs. Above properties suggest that the obtained CSUCNPs could be potential candidates for dual-mode optical/magnetic bioapplications.

关键词： boiling water upconversion nanoparticle fluorescence imaging paramagnetism

Effect of short-time low-temperature austenitizing on microstructure and mechanical properties of DT300 ultra-high strength steel fabricated by laser powder bed fusion

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Journal of Iron and Steel Research International 2024年第7期31卷 1763-1777页

作者： Chen-yang Jiang Xiao-qiang Li Jin-tao Wang Hao Luo Sheng-qing Gao Sheng-guan Qu chao yang National Engineering Research Centre of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640GuangdongChina Institute of New Materials Guangdong Academy of ScienceGuangzhou 510650GuangdongChina

To address the inhomogeneous microstructure and improve the mechanical properties of DT300 ultra-high strength steel specimens fabricated by laser powder bed fusion,different post-heat treatment schedules are *** the increase in austenitizing temperature and time,the migration rate of austenite grain boundaries continuously increases with the dissolution of nano-carbides,and the formation of nano-oxides and twin martensite is also inhibited *** rapid growth in the size of prior austenite grains and martensite laths,as well as the decrease in the content of nano-oxides and twin martensite,led to a rapid decrease in the strength(yield strength and ultimate tensile strength)from HT2 to HTF *** HT1 specimens(austenitizing at 830℃for 30 min,then oil quenching and tempering at 300℃for 120 min and finally air cooling)display excellent mechanical properties of yield strength of 1572 MPa,ultimate tensile strength of 1847 MPa,elongation of 9.84%,and fracture toughness of 106 MPa m^(1/2),which are counterparts to those of conventional DT300 steel forgings after heat treatment.

关键词： DT300 ultra-high strength steel Laser powder bed fusion-Short-time low-temperature austenitizing Microstructure Mechanical property

Oilfield analogy and productivity prediction based on machine learning: Field cases in PL oilfield, China

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Petroleum Science 2024年第4期21卷 2554-2570页

作者： Wen-Peng Bai Shi-qing Cheng Xin-yang Guo yang Wang Qiao Guo chao-Dong Tan State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing)

In the early time of oilfield development, insufficient production data and unclear understanding of oil production presented a challenge to reservoir engineers in devising effective development plans. To address this challenge, this study proposes a method using data mining technology to search for similar oil fields and predict well productivity. A query system of 135 analogy parameters is established based on geological and reservoir engineering research, and the weight values of these parameters are calculated using a data algorithm to establish an analogy system. The fuzzy matter-element algorithm is then used to calculate the similarity between oil fields, with fields having similarity greater than 70% identified as similar oil fields. Using similar oil fields as sample data, 8 important factors affecting well productivity are identified using the Pearson coefficient and mean decrease impurity（MDI） method. To establish productivity prediction models, linear regression（LR）, random forest regression（RF）, support vector regression（SVR）, backpropagation（BP）, extreme gradient boosting（XGBoost）, and light gradient boosting machine（Light GBM） algorithms are used. Their performance is evaluated using the coefficient of determination（R2）, explained variance score（EV）, mean squared error（MSE）, and mean absolute error（MAE） metrics. The Light GBM model is selected to predict the productivity of 30 wells in the PL field with an average error of only 6.31%, which significantly improves the accuracy of the productivity prediction and meets the application requirements in the field. Finally, a software platform integrating data query,oil field analogy, productivity prediction, and knowledge base is established to identify patterns in massive reservoir development data and provide valuable technical references for new reservoir development.

关键词： Data mining technique Analogy parameters Oilfield analogy Productivity prediction Software platform

Prediction of the potential distribution and analysis of the freezing injury risk of winter wheat on the Loess Plateau under climate change

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Journal of Integrative Agriculture 2024年第9期23卷 2941-2954页

作者： qing Liang Xujing yang Yuheng Huang Zhenwei yang Meichen Feng Mingxing qing chao Wang Wude yang Zhigang Wang Meijun Zhang Lujie Xiao Xiaoyan Song College of Agriculture Shanxi Agricultural UniversityTaigu 030801China Smart Agriculture College Shanxi Agricultural UniversityTaigu 030801China College of Resources and Environment Shanxi Agricultural UniversityTaigu 030801China

Determining the suitable areas for winter wheat under climate change and assessing the risk of freezing injury are crucial for the cultivation of winter *** used an optimized Maximum Entropy(MaxEnt)Model to predict the potential distribution of winter wheat in the current period(1970-2020)and the future period(2021-2100)under four shared socioeconomic pathway scenarios(SSPs).We applied statistical downscaling methods to downscale future climate data,established a scientific and practical freezing injury index(FII)by considering the growth period of winter wheat,and analyzed the characteristics of abrupt changes in winter wheat freezing injury by using the Mann-Kendall(M-K)*** results showed that the prediction accuracy AUC value of the MaxEnt Model reached *** minimum temperature in the coldest month,precipitation in the wettest season and annual precipitation were the main factors affecting the spatial distribution of winter *** total suitable area of winter wheat was approximately 4.40×10^(7)ha in the current *** the 2070s,the moderately suitable areas had the greatest increase by 9.02×10^(5)ha under SSP245 and the least increase by 6.53×10^(5)ha under *** centroid coordinates of the total suitable areas tended to move *** potential risks of freezing injury in the high-latitude and-altitude areas of the Loess Plateau,China increased *** northern areas of Xinzhou in Shanxi Province,China suffered the most serious freezing injury,and the southern areas of the Loess Plateau suffered the *** factors such as temperature,precipitation and geographical location had important impacts on the suitable area distribution and freezing injury risk of winter *** the future,greater attention should be paid to the northward boundaries of both the winter wheat planting areas and the areas of freezing injury risk to provide the early warning of freezing injury and implement corresponding management strat

关键词： climate change scenarios winter wheat freezing injury risk downscaling MaxEnt

Lung adenocarcinoma with initial binocular symptoms

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 982-984页

作者： Xiao-Lan Zhao Yan-qing Jiang Zhen yang chao-Qun Liu Xiao-Li yang Department of Ophthalmology Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina Department of Ophthalmology North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina

Dear Editor,Lung adenocarcinoma with choroidal metastasis is a common form of cancer,with breast cancer accounting for 40%-53%and lung cancer accounting for 20%-29%of primary cases with choroidal metastases[1].This type of metastatic cancer typically affects people aged 40-70y,and is more prevalent in women than men[1].Ocular symptoms,including vision loss,can be an early indication of the disease,as many tumors are asymptomatic in their early *** have shown that 40.3%of cases involve the macular region,which explains why ocular symptoms are often the first manifestation of the disease[2].When choroidal metastasis is suspected in patients without a history of cancer,a combination of diagnostic tools should be used to identify the primary source of the *** tumors can serve as an indication of future lung cancer diagnosis in some patients with lung cancer[1].In this report,we present a case of bilateral lung adenocarcinoma where ocular symptoms were the first indication of the disease.

关键词： Lung symptoms adenocarcinoma

Gastric metastasis of small cell lung carcinoma:Three case reports and review of literature

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World Journal of Gastroenterology 2024年第31期30卷 3717-3725页

作者： Shan yang qing-Yun He qing-Jing Zhao Han-Tao yang Zheng-Yi yang Wen-Yi Che Hua-Mei Li Hui-chao Wu Department of Gastroenterology The Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Department of Gastroenterology Guizhou Hospital of The First Affiliated HospitalSun Yat-sen UniversityGuiyang 550000Guizhou ProvinceChina Department of Gastroenterology Zhejiang Provincial People's Hospital Bijie HospitalBijie 551700Guizhou ProvinceChina Department of Gastroenterology Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina

BACKGROUND Small cell lung carcinoma(SCLC)is highly susceptible to metastasis in the early stages of the ***,the stomach is an uncommon site of metastasis in SCLC,and only a few cases of this type of metastasis have been ***,SCLC gastric metastases have not been systematically characterized and are easily missed and *** SUMMARY We report three cases of gastric metastasis from SCLC in this *** first patient presented primarily with cough,hemoptysis,and epigastric *** other two patients presented primarily with abdominal discomfort,epigastric distension,and *** patients underwent gastroscopy and imaging ***,the immunohistochemical results of the lesions in three patients were suggestive of small cell ***,the three patients were diagnosed with gastric metastasis of SCLC through a comprehensive *** three patients did not receive appropriate treatment and died within a short *** Here,we focused on summarizing the characteristics of gastric metastasis of SCLC to enhance clinicians'understanding of this disease.

关键词： Small cell lung cancer Gastric neoplasms Neoplasm metastasis Diagnosis Case report

Cascade electrolysis and thermocatalysis: a reliable system for upgrading C1 to C4 hydrocarbons

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Rare Metals 2024年第1期43卷 410-412页

作者： chao-Yue Sun Wen Li Hai-qing Wang Institute for Advanced Interdisciplinary Research(iAIR) College of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China

The carbon cycle is important for maintaining a stable climate and carbon balance on Earth. Renewable-electricitydriven upcycling of carbon dioxide (CO_(2)) into value-added multi-carbon molecules is a potentially sus... 详细信息

关键词： cycling hydrocarbons enable

Therapeutic genome editing of an aberrant splice site inβ-thalassemia by CRISPR/Cas9 with multiple sgRNAs

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Genes & Diseases 2024年第1期11卷 15-18页

作者： Fei yang Shuqian Xu chao Huang Zhiqiang Shao Yuefen Hu yang yang Yongrong Lai qing Ke Dan Liang Yuxuan Wu Shanghai Key Laboratory of Regulatory Biology Institute of Biomedical Sciences and School of Life SciencesEast China Normal UniversityShanghai 200241China Department of Obstetrics and Gynecology The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230022China NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract(Anhui Medical University) HefeiAnhui 230032China Department of Hematology Qilu HospitalCheeloo College of MedicineShandong UniversityJinanShandong 250012China BRLMedicine Inc. Shanghai 201108China Department of Hematology The First Affiliated Hospital of Guangxi Medical UniversityNanningGuangxi 530000China Department of Neurology The First Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310003China

Genetic mutations cause aberrant splicing,one of the important molecular mechanisms in human ***2-654,a mutation causing aberrant splicing ofβ-globin premRNA and contributing toβ-globin deficiency,is one of the most common diseases in Southeast Asia and China."In our previous work,we found a TTTV protospacer adjacent motif(PAM)by the Cas12a system and the editing efficiency of Ivs2-654 C>T achieving 76.7%.

关键词： CRISPR/Cas9 China thalassemia

Different responses of two adjacent artificial beaches to Typhoon Hato in Zhuhai,China

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Journal of Oceanology and Limnology 2024年第2期42卷 511-521页

作者： Jun ZHU qing WANG chao ZHAN Fengjuan SUN Wenhao HUA Jianhui LIU Hongshuai QI Yu yang Coastal Research Institute Ludong UniversityYantai 264025China Third Institute of Oceanography Ministry of Natural ResourcesXiamen 261005China

Major differences in beach erosion between two neighboring artificial beaches Xiangluwan Beach(XL beach)and Meiliwan Beach(ML beach)in Zhuhai,China,were studied after Super Typhoon *** this study,a fully nonlinear Boussinesq wave model(FUNWAVE)-Total Variation Diminishing(TVD)was used to distinguish the main impact factors,their relative contributions,and the hydrodynamic mechanisms underlying the different beach *** show that compared to the ML beach,the main reason for the relatively weak erosion on Xiangluwan(XL)beach was the smaller beach berm height(accounting for approximately 75.9%of the erosion response).Regarding the beach with a higher berm,the stronger wave-induced undertow flow,along with the higher sediment concentration,led to a higher offshore sediment transport flux,resulting in more severe erosion relative to the beach with a smaller berm *** second most important reason explaining the weak erosion on XL beach was the absence of seawalls(accounting for approximately 17.9%of the erosion response).Wave reflection induced by the seawall could cause higher suspended sediment concentration,resulting in a toe scouring near the *** offshore submerged breakwater protected XL beach slightly(accounting for approximately 6.1%of the erosion response).Due to the higher water level induced by storm surge,most of the wave energy could penetrate through the submerged *** effect of the larger berm width of XL beach was *** to the beach with a larger berm width,the erosion/deposition regions in the beach with a narrower berm width showed shoreward migration,without significant changes in the erosion/deposition *** of this,the larger berm width could reduce the wave energy reaching the *** study of the storm stability of artificial beaches may be applied to beach restoration design.

关键词： beach erosion berm height berm width seawall fully nonlinear Boussinesq wave model(FUNWAVE)

Crust and Upper Mantle Density Structures beneath the Eastern Tianshan Region and Its Tectonic Implications

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Journal of Earth Science 2024年第3期35卷 828-838页

作者： Yiming Liu chao Chen qing Liang Zhengwang Hu Hubei Subsurface Multi-Scale Imaging Key Laboratory School of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China

The deformation mechanisms of the Tianshan orogenic belt(TOB)are one of the most important unresolved issues in the collision of the Indian and Eurasian *** better understand the lithospheric deformation of the eastern Tianshan orogenic belt,we combined the S-wave tomography and gravity data to develop a three-dimensional(3D)density model of the crust and upper mantle beneath the eastern Tianshan *** show that the crust of the eastern Tianshan is mainly characterized by positive density anomalies,revealing widespread subduction-related magmatism during the *** however have also observed extensive low-density anomalies beneath the eastern Tianshan at depths deeper than~100 km,which is likely linked to a relatively hot *** most fundamental differences of the lithosphere within the eastern Tianshan occur in the uppermost *** uppermost mantle layers in the Bogda Shan and Harlik Shan are relatively *** is likely associated with an eclogite body in the uppermost *** most significant negative anomaly of the uppermost mantle is however found in the Jueluotage tectonic belt and the central Tianshan Block and is possibly associated with depleted mantle *** suggest that these differences related to compositional changes may control the strength of the lithospheric mantle and have affected the uplift of the northern and southern segments of the eastern Tianshan after the Permian.

关键词： constrained inversion gravity anomaly three-dimensional lithospheric density structure eastern Tianshan geodynamics geophysics.