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Rational design multi-color-emissive chemiluminescent carbon nanodots in a single solvothermal reaction

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Nano Research 2024年第6期17卷 4651-4660页

作者： Guang-Song Zheng Cheng-long shen Yuan Deng Kai-Kai Liu Jin-Hao Zang Lin Dong Qing Lou Chong-Xin Shan Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Materials PhysicsMinistry of Educationand School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China

Recently,the chemiluminescence(CL)induced by carbon nanodots(CDs)has intrigued researchers’extensive interests in various applications due to its special light emission ***,the difficulty of synthesizing chemiluminescent CDs with full-spectrum emission severely hinders the further regulation of the CL emission ***,the multi-color-emissive chemiluminescent CDs are rational designed and further synthesized by regulating the sp2-hybrid core and sp3-hybrid surface from the citrate-ammonia molecular in a single solvothermal *** experimental characterizations and density functional theory calculations reveal that the higher temperature can promote the crosslinking polymerization/carbonization of carbon core and the higher protonation of solvent can determine the core size of final CDs,resulting in the variant CL emission from molecular-,crosslinking-and ***,the CL emission of the CDs can be further synthesized by tuning the luminescence chromophores in the formation process via regulating the temperature and solvent,enabling the applications of the CL CDs in illumination and information *** study paves a new technology to understand the luminescence of CDs and affords an industry translational potential over traditional chemiluminescent molecular.

关键词： carbon nanodots chemiluminescence regulation energy level alignment mechanism

Advancing insights into in vivo meningeal lymphatic vessels with stereoscopic wide-field photoacoustic microscopy

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Light(Science & Applications) 2024年第5期13卷 894-907页

作者： Fei Yang Zhiyang Wang Wenbin Shi Miao Wang Rui Ma Wuyu zhang Xipeng Li Erqi Wang Wenjie Xie zhan zhang Qi shen Feifan Zhou Sihua Yang MOE Key Laboratory of Laser Life Science&Institute of Laser Life Science South China Normal UniversityGuangzhou 510631China. Guangdong Provincial Key Laboratory of Laser Life Science College of BiophotonicsSouth China Normal UniversityGuangzhou 510631China. Key Laboratory of Biomedical Engineering of Hainan Province School of Biomedical EngineeringHainan UniversityHaikou 570100China. Department of Neurology Sun Yatsen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120China. Guangdong Province Key Laboratory of Brain Function and Disease Zhongshan School of MedicineSun Yat-sen UniversityGuangzhou 510120China. Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter South China Normal UniversityGuangzhou 510006China

Meningeal lymphatic vessels(mLVs)play a pivotal role in regulating metabolic waste from cerebrospinal fluid(CSF).However,the current limitations in field of view and resolution of existing imaging techniques impede understanding the stereoscopic morphology and dynamic behavior of mLVs in ***,we utilized dual-contrast functional photoacoustic microscopy to achieve wide-field intravital imaging of the lymphatic system,including mLVs and glymphatic *** stereoscopic photoacoustic microscopy based on opto-acoustic confocal features has a depth imaging capability of 3.75 mm,facilitating differentiation between mLVs on the meninges and glymphatic pathways within the brain ***,using this imaging technique,we were able to visualize the dynamic drainage of mLVs and identify a peak drainage period occurring around 20–40 min after injection,along with determining the flow direction from CSF to lymph ***,in the Alzheimer’s disease(AD)mouse model,we observed that AD mice exhibit a~70%reduction in drainage volume of mLVs compared to wild-type *** the development of AD,there is be continued decline in mLVs drainage *** finding clearly demonstrates that the AD mouse model has impaired CSF *** study opens up a horizon for understanding the brain’s drainage mechanism and dissecting mLVs-associated neurological disorders.

关键词： lymphatic impaired field

Hausdorff Measure of Space Anisotropic Gaussian Processes with Non-stationary Increments

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Acta Mathematicae Applicatae Sinica 2024年

作者： Jun WANG Zhen-long CHEN Wei-jie YUAN Guang-jun shen School of Mathematics and Physics Anhui Polytechnic University School of Statistics and Mathematics Zhejiang Gongshang University Department of Mathematics Anhui Normal University

Let X={X(t), t∈R+}be a centered space anisotropic Gaussian process values in Rdwith non-stationary increments, whose components are independent but may not be identically distributed. Under certain conditions, then almost surely c1≤?-m(X([0, 1]))≤c2, where ? denotes the exact Hausdorff measure associated with function ?(s)=s(1/αk+∑i=1k(1-αi/αk)) log log 1/s for some 1≤k≤d,(α1,···, αd)∈(0, 1]d. We also obtain the exact Hausdorff measure of the graph of X on [0, 1].

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Will partial splenic embolization followed by splenectomy increase intraoperative bleeding?

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 318-330页

作者： long Huang Qing-Lin Li Qing-sheng Yu Hui Peng Zhou Zhen Yi shen Qi zhang Department of No.1 Surgery The First Hospital Affiliated to Anhui University of Traditional Chinese MedicineHefei 230031Anhui ProvinceChina Anhui University of Traditional Chinese Medicine Anhui University of Traditional Chinese MedicineHefei 230038Anhui ProvinceChina Department of Surgery The Second Hospital Affiliated to Anhui University of Traditional Chinese MedicineHefei 230061Anhui ProvinceChina

BACKGROUND Partial splenic embolization(PSE)has been suggested as an alternative to splenectomy in the treatment of ***,some patients may experience recurrence of hypersplenism after PSE and require ***,there is a lack of evidence-based medical support regarding whether preoperative PSE followed by splenectomy can reduce the incidence of *** To investigate the safety and therapeutic efficacy of preoperative PSE followed by splenectomy in patients with cirrhosis and *** Between January 2010 and December 2021,321 consecutive patients with cirrhosis and hypersplenism underwent splenectomy at our *** on whether PSE was performed prior to splenectomy,the patients were divided into two groups:PSE group(n=40)and non-PSE group(n=281).Patient characteristics,postoperative complications,and follow-up data were compared between *** score matching(PSM)was conducted,and univariable and multivariable analyses were used to establish a nomogram predictive model for intraoperative bleeding(IB).The receiver operating characteristic curve,Hosmer-Lemeshow goodness-of-fit test,and decision curve analysis(DCA)were employed to evaluate the differentiation,calibration,and clinical performance of the *** After PSM,the non-PSE group showed significant reductions in hospital stay,intraoperative blood loss,and operation time(all P=0.00).Multivariate analysis revealed that spleen length,portal vein diameter,splenic vein diameter,and history of PSE were independent predictive factors for IB.A nomogram predictive model of IB was constructed,and DCA demonstrated the clinical utility of this *** groups exhibited similar results in terms of overall survival during the follow-up *** Preoperative PSE followed by splenectomy may increase the incidence of IB and a nomogram-based prediction model can predict the occurrence of IB.

关键词： Partial splenic embolization Splenectomy Hypertension,Portal Liver Cirrhosis Intraoperative bleeding

基于大数据变量最优组合的违约预测模型——以中国小企业为例

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系统工程理论与实践 2024年第3期44卷 912-931页

作者：沈隆周颖大连理工大学经济管理学院大连116024

以提升商业银行企业客户信用风险识别和管理水平为目的,本文提出了一种系统的违约预测方法.一是在高维大数据变量集的构建上,通过基尼指数最小,反推出指标区间划分的最优切分点,确保决策树群中的每一个路径能最大限度地区分客户违约与否... 详细信息

以提升商业银行企业客户信用风险识别和管理水平为目的,本文提出了一种系统的违约预测方法.一是在高维大数据变量集的构建上,通过基尼指数最小,反推出指标区间划分的最优切分点,确保决策树群中的每一个路径能最大限度地区分客户违约与否,并把每一个路径作为一个虚拟变量,即客户属于这个路径则变量数值取1,否则为0.二是在虚拟变量的降维上,通过Lasso回归的违约预测误差最小,反推一组最优的虚拟变量组合.三是以客户判对率之和最高反推逻辑回归模型的最优违约预测临界点,提高了违约企业预测的准确率.实证研究表明,1)决策树路径变量的违约鉴别能力要强于原始信用指标,信息含量更丰富.2)净利润现金含量,城市居民人均可支配收入和企业法律纠纷情况指标对中国小企业的违约预测具有重要影响,这3个指标的个数占比是3.704%,精度贡献占比却达到了41.639%.3)该方法在准确性和稳健性方面优于对比模型,可以揭示影响企业信用风险的关键因素和关键阈值,为商业银行授信审批和贷前审查工作提供依据.且该方法可以拓展到个人以及大、中型企业违约预测模型的构建.

关键词：违约预测大数据决策树路径变量 Lasso 违约预测临界点

A wideband,high-resolution vector spectrum analyzer for integrated photonics

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Light(Science & Applications) 2024年第4期13卷 760-771页

作者： Yi-Han Luo Baoqi Shi Wei Sun Ruiyang Chen Sanli Huang Zhongkai Wang Jinbao long Chen shen Zhichao Ye Hairun Guo Junqiu Liu International Quantum Academy 518048 ShenzhenChina. shenzhen Institute for Quantum Science and Engineering Southern University of Science and Technology518055 ShenzhenChina. Department of Optics and Optical Engineering University of Science and Technology of China230026 HefeiChina. Hefei National Laboratory University of Science and Technology of China230088 HefeiChina. Qaleido Photonics 518048 ShenzhenChina. Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai University200444 ShanghaiChina

The analysis of optical spectra—emission or absorption—has been arguably the most powerful approach for discovering and understanding *** invention and development of many kinds of spectrometers have equipped us with versatile yet ultra-sensitive diagnostic tools for trace gas detection,isotope analysis,and resolving hyperfine structures of atoms and *** proliferating data and information,urgent and demanding requirements have been placed today on spectrum analysis with ever-increasing spectral bandwidth and frequency *** requirements are especially stringent for broadband laser sources that carry massive information and for dispersive devices used in information processing *** addition,spectrum analyzers are expected to probe the device’s phase response where extra information is *** we demonstrate a novel vector spectrum analyzer(VSA)that is capable of characterizing passive devices and active laser sources in one *** a dual-mode VSA can measure loss,phase response,and dispersion properties of passive *** also can coherently map a broadband laser spectrum into the RF *** VSA features a bandwidth of 55.1 THz(1260–1640 nm),a frequency resolution of 471 kHz,and a dynamic range of 56 ***,our fiber-based VSA is compact and *** requires neither high-speed modulators and photodetectors nor any active feedback ***,we employ our VSA for applications including characterization of integrated dispersive waveguides,mapping frequency comb spectra,and coherent light detection and ranging(LiDAR).Our VSA presents an innovative approach for device analysis and laser spectroscopy,and can play a critical role in future photonic systems and applications for sensing,communication,imaging,and quantum information processing.

关键词： spectrum resolution coherent

Rational Solutions of First Order Algebraic Ordinary Differential Equations

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Journal of Systems Science & Complexity 2024年第2期37卷 567-580页

作者： FENG Shuang shen Liyong School of Physical and Mathematical Sciences Nanjing Tech UniversityNanjing 211816China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

Let f(t,y,y')=∑ _(i=0)^(n )a_(i)(t,y)y'^(i)=0 be an irreducible first order ordinary differential equation with polynomial *** in 1998 proved that there exists a constant C such that every rational solution of f(t,y,y')=0 is of degree not greater than *** show that this degree bound C depends not only on the degrees of f in t,y,y' but also on the coefficients of f viewed as the polynomial in t,y,y'.In this paper,the authors show that if f satisfies deg(f,y)0,then the degree bound C only depends on the degrees of f in t,y,y',and furthermore we present an explicit expression for C in terms of the degrees of f in t,y,y'.

关键词： Degree bound first order AODE height rational solution

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Electrochemical reconstruction: a new perspective on Sn metal-organic complex microbelts as robust anode for lithium storage

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Rare Metals 2024年第1期43卷 76-86页

作者： Jin-Ke shen Nai-Teng Wu Li-Yuan Wang Gang Jiang Dong-Lei Guo Jin Li Gui-long Liu Hong-Yu Mi Huan Pang Xian-Ming Liu Key Laboratory of Function-oriented Porous Materials of Henan Province College of Chemistry and Chemical EngineeringLuoyang Normal UniversityLuoyang 471934China State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources School of Chemical Engineering and TechnologyXinjiang UniversityUrumqi 830046China School of Chemistry and Chemical Engineering Institute for Innovative Materials and EnergyYangzhou UniversityYangzhou 225009JiangsuChina

Tin-based materials with high theoretical capacity and suitable working voltage are ideal anode materials for lithium-ion batteries(LIBs). However, to overcome their shortcomings(volume expansion and inferior stability), the preparation processes are usually complicated and expensive. Herein, a tin-based metal-organic complex(tin 1,2-benzenedicarboxylic acid, Sn-BDC)with one-dimensional microbelt morphology is synthesized by a facile, rapid and low-cost co-precipitation method, and served as anode material for LIBs without any post-treatment. Sn-BDC exhibits a high reversible capacity with609/440 m Ah·g^(-1) at 50/2000 m A·g^(-1), and robust cycling stability of 856 m Ah·g^(-1) after 200 cycles at 200 m A·g^(-1),which are obviously superior to that of the Sn Ox/C counterparts. Moreover, an electrochemical reconstruction perspective on the lithium storage mechanism of Sn-BDC is proposed by systematic ex-situ characterizations. The reconstructed SnO_(2) replaces Sn-BDC and becomes the active material in the subsequent cycles. As the by-product of the lithiation reaction, the formed Li-based metal-organic complex(Li-BDC, wrapped around the reconstructed SnO_(2)) plays an important role in alleviating volume expansion and accelerating the charge transfer *** work is beneficial to design and construct the new electrode materials based on the electrochemical reconstruction for advanced LIBs.

关键词： Electrochemical reconstruction Metal-organic complex Anode Lithium storage mechanism Lithium-ion batteries

Sulfonated poly(aryl ether ketone sulfone)modified by polyoxometalates LaW_(10) clusters for proton exchange membranes with high proton conduction performance

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Tungsten 2024年第2期6卷 454-464页

作者： Meng-long Liu Xu Han Wen-Wen He Feng-Yu Jiang Fang Ji Wang-Wang shen Tao Zhou Jing-Mei Xu Ya-Qian Lan School of Chemistry and Life Science Changchun University of TechnologyChangchun 130012China Advanced Institute of Materials Science Changchun University of TechnologyChangchun 130012China School of Chemistry South China Normal UniversityGuangzhou 510006China

Polyoxometalates(POMs)are classified as solid superacids which can exhibit notable proton conductivity,making them a promising functional inorganic filler for enhancing the proton conductivity of proton exchange membranes(PEMs).In this study,a series of hybrid membranes were obtained by molecular-level hybridization of Weakley-type POM Na_(7)H_(2)LaW_(10)O_(36)(LaW_(10))clusters into sulfonated poly(aryl ether ketone sulfone)(SPAEKS).All hybrid membranes exhibited greater proton conductivity than the pristine membrane in the 30–80℃temperature *** the doping amount of LaW 10 reached 7 wt.%,the proton conductivity of M-LaW 10^(-7)achieved 64 mS·cm^(−1)at 80℃.Lanthanide ions'high coordination number property and variable coordination environment can aid to attract more water molecules from the *** 10 and these bound water can construct denser hydrogen bonds with–SO_(3)H of *** intensive hydrogen bonds will facilitate the constitution of more continuous proton transport channels,and improve the proton conductivity of the hybrid *** work off ers a fresh approach to using POMs containing rare-earth components in PEMs.

关键词： Polyoxometalates Rare-earth elements Sulfonated poly(arylene ether ketone sulfone) Proton exchange membranes